# GCN_circulars

GRB_name: GRB200111A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26795
SUBJECT: GRB 200111A: CALET Gamma-Ray Burst Monitor detection
DATE:    20/01/17 01:58:51 GMT
FROM:    Valentin Pal'shin at AGU  <val@phys.aoyama.ac.jp>

S. Torii (Waseda U),
A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
Y. Asaoka (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U),
N. Cannady (GSFC/UMBC), M. L. Cherry (LSU),
S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

The long GRB 200111A (Fermi GBM Final Real-time Localization:
The Fermi GBM team, GCN Circ. 26705; Insight-HXMT/HE detection:
Xiao et al., GCN Circ. 26714; IPN triangulation: Hurley et al.,
GCN Circ. 26778; AstroSat CZTI detection: Gaikwad et al., GCN Circ. 26783;
https://gcn.gsfc.nasa.gov/other/200111A.gcn3)
triggered the CALET Gamma-ray Burst Monitor (CGBM) at 15:11:07.610 UTC 
on 11 January 2020. The burst signal was seen by all CGBM detectors.

The burst light curve shows a multi-peaked structure followed by a short
pulse. The emission starts at T+0.0 sec, peaks at T+6.0 sec and ends at
T+6.4 sec. The T90 and T50 durations measured by the SGM data are
6.0 +- 0.5 sec and 3.9 +- 1.9 sec (40-1000 keV), respectively.

The ground processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1262790473/

The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at the Waseda University.


GRB_name: GRB200117A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26800
SUBJECT: GRB 200117A: Fermi GBM Final Real-time Localization
DATE:    20/01/17 12:34:20 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 12:24:06 UT on 17 Jan 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200117A (trigger 600956651.532182 / 200117517).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 129.7, Dec = -62.5 (J2000 degrees, equivalent to J2000 08h 38m, -62d 30'), with a statistical uncertainty of 5.3 degrees.

The angle from the Fermi LAT boresight is 133.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200117517/quicklook/glg_skymap_all_bn200117517.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200117517/quicklook/glg_healpix_all_bn200117517.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200117517/quicklook/glg_lc_medres34_bn200117517.gif


GRB_name: GRB200115A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26801
SUBJECT: GRB 200115A: AROMA-N Optical Observation
DATE:    20/01/17 12:46:20 GMT
FROM:    Takanori Sakamoto at AGU  <tsakamoto@phys.aoyama.ac.jp>

M. Nakamura, T. Sakamoto (AGU)

We observed the field of GRB 200115A detected by Swift
(Cenko et al., GCN Circ. 26771) with the 14-inch AGU Robotic
Optical Monitor for Astrophysical object - Narrow (AROMA-N)
located at the Sagamihara campus of Aoyama Gakuin University.

60 images of 60 sec exposures were taken in the R filter
starting from January 15 12:14:42 (UT) about 24 minutes
after the trigger and stopped on January 15 13:27:55 (UT).
We do not detect the optical afterglow both in the individual
images and the stacked image.  The estimated five sigma
upper limit of the combined image (total exposure of 3600 sec)
is ~18.1 mag using the USNO-B1 catalog.


GRB_name: GRB200115A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26809
SUBJECT: GRB 200115A: CALET Gamma-Ray Burst Monitor detection
DATE:    20/01/18 02:18:13 GMT
FROM:    Valentin Pal'shin at AGU  <val@phys.aoyama.ac.jp>

T. Tamura (Kanagawa U),
A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
Y. Asaoka, S. Torii (Waseda U), Y. Shimizu (Kanagawa U),
N. Cannady (GSFC/UMBC), M. L. Cherry (LSU),
S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

The very long GRB 200115A detected by Swift (Cenko et al., GCN Circ. 26771,
Laha et al., GCN Circ.26780; https://gcn.gsfc.nasa.gov/other/200115A.gcn3)
triggered the CALET Gamma-ray Burst Monitor (CGBM) at 11:52:05.424 UTC
on 15 January 2020. The burst signal was seen by all CGBM detectors.
Because of a problem in one of the ground alert processing script, the GCN
notice was not distributed automatically for this event.

The burst light curve shows a multi-peaked structure which
starts at T-206 sec, peaks at T-3 sec and ends at T+221 sec.
The T90 and T50 durations measured by the SGM data are 347 +- 46 sec
and 104 +- 29 sec (40-1000 keV), respectively.

The ground processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1263124124/

The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at the Waseda University.


GRB_name: GRB200115A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26818
SUBJECT: GRB 200115A: Mondy optical observations and correction to GCN 26790
DATE:    20/01/19 17:33:26 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

A. Volnova (IKI), A. Pozanenko (IKI),  E. Klunko (ISTP), K. Kamyshnikov 
(HSE), N. Pankov (HSE),  E. Mazaeva (IKI), S. Belkin (IKI)  report   on 
behalf of GRB IKI FuN:

We observed the field of  GRB 200115A (Cenko et al.,  GCN 26771) with 
AZT-33IK telescope of Sayan observatory (Mondy) starting on Jan. 16 (UT) 
  12:30:28. Within  BAT ground-calculated position (Laha et al. GCN 
26780) we  do not detect any  unidentified objects in comparison with 
SDSS-DR2. We also not detected the afterglow candidate reported after 
our first epoch observation (Pozanenko et al., GCN 26790).

We report the correction of R-magnitude of the afterglow candidate.
The result presented below overrides previously reported (GCN 26790) 
R-magnitude. We apologize for the typo and possible inconvenience.

Due to shallow upper limit in the second epoch observation  we cannot 
confirm variability of the afterglow candidate.

Date       UT start   t-T0       Filter Exp.    OT    Err.  UL(3sigma)
                       (mid, days)        (s)

2020-01-15 11:55:00   0.02455    R      30*120  21.9  0.2   22.1
2020-01-16 12:30:28   1.05039    R      32*120  n/d   n/d   21.6

The photometry is based on the nearby SDSS DR12 stars
SDSS                 R_Lupton
J034551.63+053704.5  17.138  0.016
J034547.51+053555.6  18.214  0.029
J034543.70+053549.4  17.851  0.022


GRB_name: GRB200120A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26831
SUBJECT: GRB 200120A: Fermi GBM Final Real-time Localization
DATE:    20/01/20 23:15:17 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 23:04:55 UT on 20 Jan 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200120A (trigger 601254300.33796 / 200120962).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 139.4, Dec = -70.7 (J2000 degrees, equivalent to J2000 09h 17m, -70d 42'), with a statistical uncertainty of 1.0 degrees.

The angle from the Fermi LAT boresight is 148.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200120962/quicklook/glg_skymap_all_bn200120962.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200120962/quicklook/glg_healpix_all_bn200120962.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200120962/quicklook/glg_lc_medres34_bn200120962.gif


GRB_name: GRB200120A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26840
SUBJECT: GRB 200120A: Insight-HXMT/HE detection
DATE:    20/01/21 16:05:04 GMT
FROM:    YaoGuang Zheng at IHEP  <zhengyg@ihep.ac.cn>

Y. G. Zheng, C. Cai, Y. F. Du, W. C. Xue, 
Q. Luo, S. Xiao, Q. B. Yi, Y. Huang, C. K. Li, G. Li, 
X. B. Li, J. Y. Liao, S. L. Xiong,C. Z. Liu, 
X. F. Li, Z. W. Li, Z. Chang, A. M. Zhang, Y. F. Zhang, 
X. F. Lu, C. L. Zou (IHEP), Y. J. Jin, Z. Zhang (THU), 
T. P. Li (IHEP/THU), F. J. Lu, L. M. Song, 
M. Wu, Y. P. Xu, S. N. Zhang (IHEP), 
report on behalf of the Insight-HXMT team:

At 2020-01-20T23:04:58.60 (T0), Insight-HXMT/HE detected 
GRB 200120A (trigger ID: HEB200120961) in a routine search of the data, 
which also triggered Fermi/GBM (GCN #26831).

The Insight-HXMT/HE light curve mainly consists of a single  
pulse with a duration (T90) of 5.66 s measured from T0-2.86 s. 
The 1-ms peak rate, measured from T0-0.08 s, is 890 cnts/sec. 
The total counts from this burst is 2641 counts. 
URL_LC: http://www.hxmt.org/images/GRB/HEB200120961_lc.jpg 

All measurements above are made with the CsI detectors operating in the 
regular mode with the energy range of about 80-800 keV (deposited energy). 
Only gamma-rays with energy greater than about 200 keV can penetrate 
the spacecraft and leave signals in the CsI detectors installed inside 
of the telescope. 

Insight-HXMT is the first Chinese space X-ray telescope, which was 
funded jointly by the China National Space Administration (CNSA) and 
the Chinese Academy of Sciences (CAS). 
More information about it could be found at: 
http://www.hxmt.org.


GRB_name: GRB191031D
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26841
SUBJECT: GRB 191031D: XMM-Newton upper limit
DATE:    20/01/21 16:38:21 GMT
FROM:    Paolo D'Avanzo at INAF-OAB  <pda.davanzo@gmail.com>

P. D'Avanzo, S. Campana, M. G. Bernardini (INAF-OAB), M. Branchesi (GSSI), E. Chassande-Mottin (APC, CNRS/IN2P3), 
S. Covino (INAF-OAB), V. D'Elia (ASI-SSDC), G. Ghirlanda, G. Ghisellini, A. Melandri, L. Nava, O. S. Salafia (INAF-OAB), 
R. Salvaterra (INAF-IASFMi), G. Tagliaferri (INAF-OAB), S. D. Vergani (GEPI/Obs. Paris) report:

XMM-Newton started observing the field of the short GRB 191031D (Fermi-GBM et al., GCN Circ. 26111; D'Elia et al., GCN Circ. 26112; 
Mailyan et al., GCN Circ. 26118; Ursi et al., GCN Circ. 26123; Frederiks et al., GCN Circ. 26126; Gaikwad et al., GCN Circ. 26129; 
Frederiks et al., GCN Circ. 26149; Shimizu et al., GCN Circular. 26240) on 14 November 2019 at 09:58:00 UT, ~ 13.5 d after the burst. 
The last ~18 ks of the observation were affected by an enhanced background and were filtered out. The resulting EPIC/pn exposure 
time is 27.2 ks. 

No X-ray source is detected within the enhanced XRT position (Osborne et al., GCN Circ. 26117) down to a 3sigma limit of ~ 1.6e-3 cts/s 
in the 0.3-10 keV energy range. Assuming the spectral parameters derived by Swift/XRT, the above value translates into an unabsorbed 
flux limit of ~ 4.8e-15 erg/cm^2/s in the 0.3-10 keV energy range. 


We acknowledge the XMM-Newton staff for their support in scheduling and executing these observations.


GRB_name: GRB200122A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26844
SUBJECT: GRB 200122A: Swift detection of a burst
DATE:    20/01/22 02:08:43 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

E. Sonbas (Adiyaman Univ.), C. Gronwall (PSU), J.D. Gropp (PSU),
J. A. Kennea (PSU), N. J. Klingler (PSU), F. E. Marshall (NASA/GSFC),
M. J. Moss (GWU), K. L. Page (U Leicester), D. M. Palmer (LANL),
M. H. Siegel (PSU) and A. Tohuvavohu (U Toronto) report on behalf of
the Neil Gehrels Swift Observatory Team:

At 01:41:00 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 200122A (trigger=950330).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 209.981, +27.566 which is 
   RA(J2000) = 13h 59m 55s
   Dec(J2000) = +27d 33' 56"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a complex
structure with a duration of about 50 sec.  The peak count rate
was ~11000 counts/sec (15-350 keV), at ~10 sec after the trigger. 

The XRT began observing the field at 01:42:12.5 UT, 72.2 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
uncatalogued X-ray source located at RA, Dec 210.01625, 27.54988 which
is equivalent to:
   RA(J2000)  = 14h 00m 03.90s
   Dec(J2000) = +27d 32' 59.6"
with an uncertainty of 3.5 arcseconds (radius, 90% containment). This
location is 126 arcseconds from the BAT onboard position, within the
BAT error circle. This position may be improved as more data are
received; the latest position is available at
https://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value (1.54 x
10^20 cm^-2, Willingale et al. 2013), with an excess column of 1
(+0.55/-0.45) x 10^22 cm^-2 (90% confidence). 

The initial flux in the 2.5 s image was 9.13e-10 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 81 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of
the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. 
The 8'x8' region for the list of sources generated on-board covers 100% of the
XRT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.03. 

Burst Advocate for this burst is E. Sonbas (edasonbas AT yahoo.com). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB200122A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26845
SUBJECT: Swift GRB 200122A: Global MASTER-Net observations report 
DATE:    20/01/22 04:18:40 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, 
V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva,
D.Kuvshinov,  D. Cheryasov
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile 
(Observatorio Astronomico Felix Aguilar OAFA),

H.Levato 
(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE),

R. Rebolo, M. Serra 
(The Instituto de Astrofisica de Canarias),

D. Buckley 
(South African Astronomical Observatory),

O.A. Gres, N.M. Budnev, O.Ershova 
(Irkutsk State University, API),

A. Tlatov, D. Dormidontov 
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich, Yu. Sergienko 
(Blagoveschensk Educational State University)




MASTER-IAC robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Spain (IAC Teide Observatory) was pointed to the Swift GRB 200122A ( E. Sonbas et al., GCN 26844) errorbox  8770 sec after trigger time at 2020-01-22 04:07:10 UT, with upper limit up to  19.4 mag. The observations began at zenith distance = 38 deg. The sun  altitude  is -49.9 deg. 

The galactic latitude b = 74 deg., longitude l = 38 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1266128

We obtain a following upper limits.  

Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________

    8860 |          MASTER-IAC |   C |   180 | 19.4 |        
    8860 |          MASTER-IAC |   C |   180 | 19.2 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.


GRB_name: GRB200122A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26846
SUBJECT: GRB 200122A: Enhanced Swift-XRT position
DATE:    20/01/22 04:59:55 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 1627 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 200122A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 210.01807, +27.54884 which is equivalent
to:

RA (J2000): 14h 00m 4.34s
Dec (J2000): +27d 32' 55.8"

with an uncertainty of 1.7 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB200120A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26851
SUBJECT: GRB 200120A: AstroSat CZTI detection
DATE:    20/01/22 12:06:37 GMT
FROM:    Ramkrishna Gaikwad at IUCAA/AstroSat  <ramkrishna@iucaa.in>

R. Gaikwad, S. Gupta, V. Sharma and D. Bhattacharya (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data showed a weak detection of a long GRB 200120A, which was also detected by Fermi GBM Final Real-time Localization (GCN #26831) and IceCube (Lagunas C. et al., GCN #26832).

The source was clearly detected in the 40-200 keV energy range. The light curve showed a single peak of emission peaking at 2020-01-20 23:04:55.0 UT. The measured peak count rate associated with the burst is 156 cts/s above the background in the combined data of four quadrants, with a total of 805 cts. The local mean background count rate was 678 cts/s. Using cumulative rates, we measure a T90 of 9.8 s.

It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.

CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.


GRB_name: GRB200122A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26852
SUBJECT: GRB 200122A: Swift-XRT refined Analysis
DATE:    20/01/22 13:20:52 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J. D. Gropp (PSU), A. Tohuvavohu (U. Toronto), J.A. Kennea (PSU), P.A.
Evans (U. Leicester), J.P. Osborne (U. Leicester), K.L. Page (U.
Leicester), A. D'Ai (INAF-IASFPA), A. Melandri (INAF-OAB), P. D'Avanzo
(INAF-OAB) and E. Sonbas report on behalf of the Swift-XRT team:

We have analysed 6.4 ks of XRT data for GRB 200122A (Sonbas et al. GCN
Circ. 26844), from 63 s to 35.2 ks after the  BAT trigger. The data
comprise 296 s in Windowed Timing (WT) mode (the first 8 s were taken
while Swift was slewing) with the remainder in Photon Counting (PC)
mode. The enhanced XRT position for this burst was given by Osborne et
al. (GCN Circ. 26846).

The late-time light curve (from T0+5.3 ks) can be modelled with a
power-law decay with a decay index of alpha=0.67 (+0.11, -0.10).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.84 (+/-0.05). The
best-fitting absorption column is  1.44 (+/-0.07) x 10^22 cm^-2, in
excess of the Galactic value of 1.5 x 10^20 cm^-2 (Willingale et al.
2013). The PC mode spectrum has a photon index of 2.25 (+/-0.14) and a
best-fitting absorption column of 1.70 (+0.18, -0.17) x 10^22 cm^-2.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum  is 5.1 x 10^-11 (1.3 x 10^-10) erg cm^-2
count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      1.70 (+0.18, -0.17) x 10^22 cm^-2
Galactic foreground: 1.5 x 10^20 cm^-2
Excess significance: 16.2 sigma
Photon index:      2.25 (+/-0.14)

If the light curve continues to decay with a power-law decay index of
0.67, the count rate at T+24 hours will be 0.11 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 5.7 x
10^-12 (1.5 x 10^-11) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00950330.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB200122A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26853
SUBJECT: GRB 200122A: GOTO non-detection of optical afterglow
DATE:    20/01/22 13:31:25 GMT
FROM:    Joe Lyman at U of Warwick  <j.d.lyman@warwick.ac.uk>

K.Wiersema (1); D.Steeghs (1); K.Ulaczyk (1); J.Lyman (1); R.Cutter
(1); T.Killestein (1); M.Dyer (3); M.Kennedy (10); G.Ramsay (5);
D.K.Galloway (2); V.Dhillon (3); P.Oâ€™Brien (4); D.Pollacco (1);
E.Thrane (2); S.Poshyachinda (6); S.Mattila (7); L.Nuttall (8);
E.Palle (9); A.Levan (1); T.Marsh (1); R.West (1); E.Stanway (1);
B.Gompertz (1); J.McCormac (1); P.Strom (1); K.Ackley (2);
Y.-L.Mong (2); A.Casey (2); M.Brown (2); B.Muller (2);
J.Mullaney (3); E.Daw (3); S.Littlefair (3); J.Maund (3);
L.Makrygianni (3); R.Starling (4); R.Eyles (4); S.Tooke (4);
S.Aukkaravittayapun (6); U.Sawangwit (6); S.Awiphan (6);
D.Mkrtichian (6); P.Irawati (6); R.Kotak (7); T.Heikkila (7); E.Rol
(2)
(1) Warwick University, (2) Monash University, (3) University of
Sheffield, (4) University of Leicester, (5) Armagh Observatory &
Planetarium, (6) National Astronomical Research Institute of
Thailand, (7) University of Turku, (8) University of Portsmouth, (9)
Instituto de Astrofisica de Canarias), (10) Univ. of Manchester.

report on behalf of the GOTO collaboration:

We carried out observations with the Gravitational-wave Optical
Transient Observer (GOTO), in response to GRB 200122A
(Sonbas et al. 2020; GCN #26844).

We made a series of 3 x 60 s exposures using our wide L-band filter
(400-700 nm) covering the Swift XRT position RA, Dec = 210.01807,
+27.54884 (Osborne et al. 2020; GCN #26846), with midtime 02:35:49
UT on 22 January 2020 (3289 seconds after trigger).

Using a difference imaging analysis with recent survey observations
of the same pointings as reference, we identify no viable
afterglow candidate. Our 5-sigma detection limit was g=19.5 mag
based on PS1 catalogue calibrators.

GOTO is operated at the La Palma observing facilities of the
University of Warwick on behalf of a consortium including the
University of Warwick, Monash University, Armagh Observatory, the
University of Leicester, the University of Sheffield, the National
Astronomical Research Institute of Thailand (NARIT) and the Instituto
de Astrofisica de Canarias (IAC) (https://goto-observatory.org)


GRB_name: GRB200122A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26854
SUBJECT: GRB 200122A: FRAM-ORM optical limit
DATE:    20/01/22 15:58:16 GMT
FROM:    Martin Jelinek at Astro.Inst-AVCR,Ondrejov  <martin.jelinek@asu.cas.cz>

Martin Jelinek, Jan Strobl (ASU CAS Ondrejov, CZ),
Martin Masek, Petr Janecek, Sergey Karpov, Jakub Jurysek,
Jan Ebr, Ronan Cunniffe, Petr Travnicek and Michael Prouza
(Institute of Physics, Prague, CZ)

report:

The 25cm robotic telescope FRAM-ORM at La Palma (Spain)
reacted robotically to the alert of GRB200122A (Sonbas et
al, GCNC 26844), obtaining a series of 20s unfiltered images
starting at 01:41:33.0UT, i.e. 32.6s post trigger.

We do not detect any new source in comparison to USNO-B2.0
catalog neither in single images (3-sigma limit R>~17.4)
nor in a combined 40x20s frame (mean exp time 551s post
trigger, 3-sigma limit R>~19.3).


GRB_name: GRB200120A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26856
SUBJECT: IPN Triangulation of GRB 200120A
DATE:    20/01/22 18:11:06 GMT
FROM:    Anna Ridnaia at Ioffe Institute  <ridnaia@mail.ioffe.ru>

K. Hurley, on behalf of the IPN,

I. G. Mitrofanov, D. V. Golovin, A. S. Kozyrev, M. L. Litvak,
and A. B. Sanin, on behalf of the HEND-Odyssey GRB team,

A. Ridnaia, S. Golenetskii, R. Aptekar, D. Frederiks, D. Svinkin,
and T. Cline on behalf of the Konus-Wind team,

A. Goldstein, M. S. Briggs, and C. Wilson-Hodge
on behalf of the Fermi GBM team,

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,

S. Barthelmy, J. Cummings, H. Krimm, and D. Palmer,
on behalf of the Swift-BAT team, and

W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr,
on behalf of the GRS-Odyssey GRB team, report:

The long-duration GRB 200120A (The Fermi GBM team, GCN Circ. 26831;
Insight-HXMT/HE detection: Zheng et al., GCN Circ. 26840;
AstroSat CZTI detection: Gaikwad et al., GCN Circ. 26851)
was detected by Konus-Wind, Fermi (GBM trigger 601254300),
INTEGRAL (SPI-ACS), Mars-Odyssey (HEND), Insight (HXMT/HE),
AstroSat (CZTI), and Swift (BAT) at about 83095 s UT (23:04:55).
The burst was outside the coded field of view of the BAT.

We have triangulated it to a preliminary, 3 sigma error box
whose coordinates are:
  ---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
   137.180 (09h 08m 43s) -70.389 (-70d 23' 22")
  Corners:
   136.684 (09h 06m 44s) -70.872 (-70d 52' 19")
   136.099 (09h 04m 24s) -70.854 (-70d 51' 15")
   137.657 (09h 10m 38s) -69.906 (-69d 54' 21")
   138.218 (09h 12m 52s) -69.919 (-69d 55' 08")
  ---------------------------------------------
The error box area is 686 sq. arcmin, and its maximum
dimension is 1.2 deg (the minimum one is 10.6 arcmin).
The Sun distance was 88 deg.

This box may be improved.

The IPN localization is consistent with, but reduces
the area of, the Fermi-GBM (GCN Circ. 26831) and
BALROG (https://grb.mpe.mpg.de/grb/GRB200120962) one.

This event is spatially and temporally inconsistent
with the IceCube 200120A neutrino candidate event (GCN Circ. 26832).

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB200120_T83096/IPN/

The Konus-Wind time history and spectrum will be given in a forthcoming
GCN Circular.


GRB_name: GRB200120A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26857
SUBJECT: Konus-Wind observation of GRB 200120A
DATE:    20/01/22 18:18:59 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

D. Frederiks, S. Golenetskii, R. Aptekar, A. Lysenko,
A. Ridnaia, D. Svinkin, A. Tsvetkova, M. Ulanov, and T. Cline
on behalf of the Konus-Wind team, report:

The long GRB 200120A (Fermi GBM localization: GCN 26831;
IPN triangulation: Hurley et al., GCN 26856;
Insight-HXMT/HE detection: Zheng et al., GCN 26840)
triggered Konus-Wind at T0=83096.553 s UT (23:04:56.553).

The burst light curve shows a mult-peaked pulse
which starts at ~T0-5 s and has a total duration of ~12 s.
The emission is seen up to ~2 MeV.

As observed by Konus-Wind, the burst
had a fluence of 8.2(-0.7,+0.8)x10^-6 erg/cm2,
and a 64-ms peak flux, measured from T0+3.368 s,
of 4.0(-0.5,+0.4)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-integrated spectrum of the burst
(measured from T0 to T0+8.448 s)
is best fit in the 20 keV - 15 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with  alpha = -1.12(-0.15,+0.17)
and Ep = 221(-32,+47) keV (chi2 = 105/98 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2.3
(chi2 =105/97 dof).

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB200120_T83096/

All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.


GRB_name: GRB200122A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26859
SUBJECT: GRB 200122A: Swift/UVOT Upper Limits 
DATE:    20/01/22 23:29:02 GMT
FROM:    Mike Siegel at PSU/Swift MOC  <mhs18@psu.edu>

A. Belles (PSU) and E. Sonbas (Adiyaman Univ.)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 200122A
82 s after the BAT trigger (Sonbas et al., GCN Circ. 26844).
No optical afterglow consistent with the XRT position
(Osborne et al. GCN Circ. 26846)
is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_fc            82          232          147         >21.1
u_fc               294          544          246         >20.9
white               82         5672          627         >21.7
v                  624         6083          352         >19.4
b                  550         5467          333         >20.6
u                  294         1844          363         >20.7
w1                 674         1472           58         >20.1
m2                6088         6276          186         >19.5
w2                5678         5878          197         >20.3

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.03 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB200122A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26860
SUBJECT: GRB 200122A: Xinglong-2.16m optical upper limit
DATE:    20/01/23 01:24:01 GMT
FROM:    Dong Xu at NAOC/CAS  <dxu@nao.cas.cn>

X. Liu, D. Xu, H.J. Wang, Z.P. Zhu, B.Y. Yu (NAOC) report:

We observed the field of GRB 200122A (Sonbas et al., GCN 26844) using 
the Xinglong-2.16m telescope equipped with the BFOSC camera. 
Observations started at 22:14:52 UT on 2020-01-22 (i.e., 20.57 h after 
the BAT trigger), and 5x200 s R-band frames have been obtained.

No optical afterglow is detected at the Swift XRT's position in our 
stacked image, down to a limiting magnitude of m(R) ~ 22.0, calibrated 
with the nearby PanSTARRS field.


GRB_name: GRB200122A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26861
SUBJECT: GRB 200122A: Swift-BAT refined analysis
DATE:    20/01/23 02:01:53 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

A. Y. Lien (GSFC/UMBC), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), H. A. Krimm (NSF),
S. Laha (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU),
E. Sonbas (Adiyaman Univ.), M. Stamatikos (OSU),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-240 to T+302 sec from the recent telemetry
downlink,
we report further analysis of BAT GRB 200122A (trigger #950330)
(Sonbas et al., GCN Circ. 26844).  The BAT ground-calculated position is
RA, Dec = 210.010, 27.548 deg which is
   RA(J2000)  =  14h 00m 02.4s
   Dec(J2000) = +27d 32' 52.2"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 78%.

The mask-weighted light curve shows a multi-peaked structure that starts
from ~T-10 s and ends at ~T+200 s. The main emission interval is
around T-10 s to T+50 s, with the highest peak occurs at ~T+10 s.
In addition, there is a weak pulse around ~T+192 s.
T90 (15-350 keV) is 174.96 +- 14.54 sec (estimated error including
systematics).

The time-averaged spectrum from T-8.572 to T+201.832 sec is best
fit by a simple power-law model.  The power law index of the
time-averaged spectrum is 1.60 +- 0.05.  The fluence in the 15-150 keV
band is 1.1 +- 0.03 x 10^-5 erg/cm2. The 1-sec peak photon flux measured
from T+10.18 sec in the 15-150 keV band is 9.1 +- 0.4 ph/cm2/sec.
All the quoted errors are at the 90% confidence level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/950330/BA/


GRB_name: GRB200122A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26862
SUBJECT: GRB 200122A: RATIR Optical Observations 
DATE:    20/01/23 04:14:06 GMT
FROM:    Alan M Watson at UNAM  <alan@astro.unam.mx>

Alan M. Watson (UNAM), Nat Butler (ASU), Alexander Kutyrev (GSFC),
William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J.
Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI),
Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz
(UCSC), JesÃºs GonzÃ¡lez (UNAM), Carlos RomÃ¡n-ZÃºÃ±iga (UNAM), Harvey
Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (U. Wash.), and Vicki
Toy (UMD) report:

We observed the field of GRB 200122A (Sonbas et al., GCN Circ. 26844)
with the Reionization and Transients Infrared Camera (RATIR;
www.ratir.org) on the 1.5m Harold Johnson Telescope at the Observatorio
AstronÃ³mico Nacional on Sierra San Pedro MÃ¡rtir from 2020/01 22.35 to
2020/01 22.56 UTC (6.67 to 11.76 hours after the BAT trigger), obtaining
a total of 3.76 hours exposure in the r and i bands.

For a source within the Swift-XRT enhanced error circle (Osborne et al.,
GCN Circ. 26846), in comparison with the SDSS DR9 and 2MASS catalogs, we
obtain the following 3-sigma upper limits:

  r > 23.72
  i > 23.42

These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.

We thank the staff of the Observatorio AstronÃ³mico Nacional in San Pedro
MÃ¡rtir.


GRB_name: GRB200122A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26864
SUBJECT: GRB 200122A: MITSuME Akeno optical upper limits
DATE:    20/01/23 06:48:06 GMT
FROM:    Adachi Ryo at Tokyo Institute of Tech  <adachi@hp.phys.titech.ac.jp>

R. Adachi, K. L. Murata, M. Niwano, F. Ogawa, R. Hosokawa, N.
Nakamura, S. Toma, M. Oeda, K. Shiraishi, K. Iida, Y. Yatsu, and N.
Kawai(TokyoTech) report on behalf of the MITSuME collaboration:

We searched for the optical counterpart of GRB 200122A (E. Sonbas et
al.,GCN Circular #26844) with the optical three color (g', Rc, and Ic)
CCD cameras attached to the MITSuME 50 cm telescope of Akeno
Observatory, Yamanashi, Japan.
The observation started on 14:39:41 UT. Then the observation stopped
due to the bad weather and started again at 16:20:20 UT. We did not
find any new point sources within the Swift-XRT error circle (J.P.
Osborne et al., GCN Circular #26846) in all three bands.

We obtained the 5-sigma limits as follows.

T0+[hour] MID-UT T-EXP[sec] 5-sigma limits
------------------------------------------------------------------------------------------------
14.66 17:41:47 7140 g'>18.6,Rc>18.8,Ic>18.1
------------------------------------------------------------------------------------------------

T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
We used Pan-STARRS DR1 catalog for flux calibration.
The magnitudes are expressed in the AB system.
The images were processed in real-time through the MITSuME GPU
reduction pipeline (Niwano et al. ,in prep;
https://github.com/MNiwano/Eclair)


GRB_name: GRB200122A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26865
SUBJECT: Konus-Wind observation of GRB 200122A
DATE:    20/01/23 12:24:17 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

D. Frederiks, S. Golenetskii, R.Aptekar, A.Lysenko,
A. Ridnaia, D. Svinkin, A. Tsvetkova,  M. Ulanov, and T. Cline,
on behalf of the Konus-Wind team, report:

The long GRB 200122A (Swift detection:  Sonbas et al., GCN 26844)
triggered Konus-Wind (KW) at T0=6066.859 s UT (01:41:06.859).

The burst light curve shows a multi-peaked structure
in the interval from ~T0-12 s to ~T0+26 s.
The total duration of the burst is ~40 s.
The emission is seen up to ~10 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB200122_T06066/

As observed by Konus-Wind, the burst had
a fluence of (2.0 Â± 0.3)x10^-5 erg/cm^2 and
a 64-ms peak energy flux, measured from T0+6.080,
of (5.7 Â± 0.7)x10^-6 erg/cm^2/s (both in the 20 keV - 10 MeV energy range).

The time-integrated spectrum (measured from T0 to T0+24.832 s)
is best fit in the 20 keV - 20 MeV range
by the GRB (Band) function with the following model parameters:
the low-energy photon index alpha = -1.00 (-0.13,+0.16),
the high energy photon index beta = -2.81 (-0.94,+0.32),
the peak energy Ep = 148 (-16,+15) keV,
chi2 = 83/96 dof.

The spectrum near the peak count rate (measured from T0
to T0+8.448 s) is best fit in the 20 keV - 15 MeV range
by the GRB (Band) function with the following model parameters:
the low-energy photon index alpha = -0.88 (-0.16,+0.19),
the high energy photon index beta = -2.37 (-0.39,+0.16),
the peak energy Ep = 168 (-22,+31) keV,
chi2 = 83/96 dof.

All the quoted errors are estimated at the 68% confidence level.
All the presented results are preliminary.


GRB_name: GRB200122A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26869
SUBJECT: GRB 200122A: Mondy optical upper limit
DATE:    20/01/24 13:19:45 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

S. Belkin (IKI), A. Pozanenko (IKI), E. Klunko (ISTP),  E. Mazaeva 
(IKI), A. Volnova (IKI) report   on behalf of IKI-GRB-FuN:

We observed the field of  GRB 200122A (Sonbas et al.  GCN 26844) with 
AZT-33IK telescope of Sayan observatory (Mondy) starting on Jan. 22 (UT) 
  20:23:25.   We  do not detect any optical object in the Enhanced 
Swift-XRT position  (Osborne et al.  GCN 26846). Preliminary photometry 
of the field  is following.

Date       UT start   t-T0       Filter Exp.    OT       UL(3sigma)
                       (mid, days)        (s)

2020-01-22 20:23:25   0.79876     R     30*120  n/d      23.3

Photometry is based on the USNO-B2.0 nearby stars
USNO-B1.0_id R2
1175-0271901 16.74
1174-0271881 19.69


GRB_name: GRB200122A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26870
SUBJECT: GRB 200122A: Optical upper limit
DATE:    20/01/24 14:50:35 GMT
FROM:    Dimple Panchal at ARIES, India  <dimple@aries.res.in>

Dimple, R. Gupta, V.K. Jha, A. Aryan, A. Ghosh, K. Misra, A. Kumar, and S.B. Pandey report: 

We carried out observation of GRB 200122A (Sonbas et al., GCN Circ. 26844) with the 1.3m Devasthal Fast Optical Telescope (DFOT) at Devasthal observatory of Aryabhatta Research Institute of observational sciencES (ARIES), India. 
The observation was started on 2020-01-23 at 10:29:41 UT. We observed a series of 3 x 300s exposures using R filter (Johnson-Cousins) covering Swift XRT enhanced position RA, Dec = 210.01807,+2754884 (Osborne et al., GCN Circ. 26846). 

We do not detect any new optical source within the Swift XRT enhanced error circle neither in single images nor in the combined image. 

We obtained the 3-sigma upper limit as follows 

T_start-T0 (hours) Start_UT End_UT Filter 3-sigma upper limit 
------------------------------------------------------------------------------------------------- 
8.8 10:29:41 10:44:41 R >21.13 
------------------------------------------------------------------------------------------------- 

Photometry is done based on USNO-B1.0 catalog. This magnitude is not corrected for Galactic extinction in the direction of the GRB. 


GRB_name: GRB200122A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26871
SUBJECT: GRB 200122A: AstroSat CZTI detection
DATE:    20/01/24 14:51:04 GMT
FROM:    Ramkrishna Gaikwad at IUCAA/AstroSat  <ramkrishna@iucaa.in>

R. Gaikwad, S. Gupta, V. Sharma and D. Bhattacharya (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data showed the detection of a long GRB 200122A, which was also detected by Swift (Sonbas E. et al., GCN #26844), Global MASTER-Net (Lipunov V. et al., GCN #26845), Swift-XRT (Osborne J. et al., GCN #26846), GOTO (Wiersema K. et al., GCN #26853), Swift/UVOT (Belles A. et al., GCN #26859), Xinglong-2.16m (Liu X. et al., GCN #26860), RATIR (Watson A. et al., GCN #26862), MITSuME Akeno ( Adachi R. et al., GCN #26864) and Konus-Wind (Frederiks D. et al., GCN #26864).

The source was clearly detected in the 40-200 keV energy range. The light curve showed multiple peak of emissions with the strongest peak at 2020-01-22 01:41:00.0 UT. The measured peak count rate associated with the burst is 74 cts/s above the background in the combined data of four quadrants, with a total of 5463 cts. The local mean background count rate was 664 cts/s. Using cumulative rates, we measure a T90 of 39.3 s.

It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.

CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.


GRB_name: GRB200115A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26872
SUBJECT: GRB 200115A: Assy optical observations
DATE:    20/01/24 17:57:09 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

A. Volnova (IKI), V. Kim (AFIF), A. Pozanenko (IKI), M. Krugov (AFIF), 
E. Mazaeva  (IKI), S. Belkin (IKI) report on behalf of larger GRB IKI 
FuN collaboration:

We observed the field of  GRB 200115A (Cenko et al.,  GCN 26771)  with 
AZT-20 1.5 m telescope  of Assy-Turgen observatory  starting on Jan. 18 
(UT) 16:55:27  in  r'-filter.   We do not detect the afterglow candidate 
(GCNs 26790, 26818) up to r'=22.8 (AB) and hence we consider the object 
found in BAT error circle (Cenko et al.,  GCN 26771) as the optical 
afterglow of GRB 200215A.

Photometry of the field is following.

Date       UT start   t-T0       Filter Exp.   OT   UL (3sigma)
                       (mid, days)        (s)

2019-10-18 16:55:27   3.22608     r'    13*180 n/d  22.8

The photometry is based on the nearby SDSS-DR12 stars.


GRB_name: GRB200122A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26873
SUBJECT: GRB 200122A: Optical upper limit: correction to the GCN circ. 26870
DATE:    20/01/24 18:07:16 GMT
FROM:    Dimple Panchal at ARIES, India  <dimple@aries.res.in>

Dimple, R. Gupta, V. K. Jha, A. Aryan, A. Ghosh, K. Misra, A. Kumar, and S. B. Pandey report: 

We carried out observation of GRB 200122A (Sonbas et al., GCN Circ. 26844) with the 1.3m Devasthal Fast Optical Telescope (DFOT) at the Devasthal observatory of Aryabhatta Research Institute of observational sciencES (ARIES), India. 
The observation was started on 2020-01-22 at 23:34:50 UTC. We observed a series of 3 x 300s exposures using R filter (Johnson-Cousins) covering Swift XRT enhanced position RA, Dec = 210.01807, +27.54884 (Osborne et al., GCN Circ. 26846). 

We do not detect any new optical source within the Swift XRT enhanced error circle neither in single image nor in the combined image. 

We obtained the 3-sigma upper limit as follows 

T_start-T0 (hours) Start_UTC End_UTC Filter 3-sigma upper limit 
------------------------------------------------------------------------------------------------------- 
21.9 23:34:50 23:49:50 R >21.13 
------------------------------------------------------------------------------------------------------- 

Photometry is done based on USNO-B1.0 catalog. This magnitude is not corrected for Galactic extinction in the direction of the GRB. 


GRB_name: GRB200125A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26876
SUBJECT: GRB 200125A: Swift detection of a burst
DATE:    20/01/25 11:44:25 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

A. Y. Lien (GSFC/UMBC), C. Gronwall (PSU), J.D. Gropp (PSU),
F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester),
K. K. Simpson (PSU), A. Tohuvavohu (U Toronto) and
E. Troja (NASA/GSFC/UMCP) report on behalf of the Neil Gehrels Swift
Observatory Team:

At 11:31:39 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 200125A (trigger=952164).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 228.047, -8.148 which is 
   RA(J2000) = 15h 12m 11s
   Dec(J2000) = -08d 08' 53"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a complex
structure with a duration of at least 40 sec.  The peak count rate
was ~1000 counts/sec (15-350 keV), at ~5 sec after the trigger. 

The XRT began observing the field at 11:33:30.7 UT, 111.5 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 228.0471, -8.1436 which is equivalent to:
   RA(J2000)  = 15h 12m 11.30s
   Dec(J2000) = -08d 08' 37.0"
with an uncertainty of 4.9 arcseconds (radius, 90% containment). This
location is 15 arcseconds from the BAT onboard position, within the BAT
error circle. No event data are yet available to determine the column
density using X-ray spectroscopy. 

The initial flux in the 2.5 s image was 3.86e-09 erg cm^-2 s^-1 (0.2-10
keV). 

There are no UVOT data available at this time. 

Burst Advocate for this burst is A. Y. Lien (amy.y.lien AT nasa.gov). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB200122B
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26877
SUBJECT: GRB 200122B: Insight-HXMT/HE detection
DATE:    20/01/25 14:13:08 GMT
FROM:    QiBin Yi at IHEP, HXMT  <yiqb@ihep.ac.cn>

GRB 200122B: Insight-HXMT/HE detection

Q. B. Yi, S. Xiao, Q. Luo, C. Cai, C. K. Li,
X. B. Li, G. Li, J. Y. Liao, S. L. Xiong, 
C. Z. Liu, X. F. Li, Z. W. Li, Z. Chang, X. F. Lu,
A. M. Zhang, Y. F. Zhang, C. L. Zou (IHEP), Y. J. Jin, 
Z. Zhang (THU), T. P. Li (IHEP/THU), F. J. Lu, L. M. Song, 
M. Wu, Y. P. Xu, S. N. Zhang (IHEP),
report on behalf of the Insight-HXMT team:

At 2020-01-22T05:18:20.20 (T0), Insight-HXMT/HE detected 
GRB 200122B (trigger ID: HEB200122221) in a routine search of the data, 
which was also triggered by Fermi/GBM (NUM #601363105). 

The Insight-HXMT/HE light curve mainly consists of a single  
pulse with a duration (T90) of 2.16 s measured from T0-0.53 s. 
The 1-ms peak rate, measured from T0-0.06 s, is 1340 cnts/sec. 
The total counts from this burst is 1335 counts. 
URL_LC: http://www.hxmt.org/images/GRB/HEB200122221_lc.jpg 

All measurements above are made with the CsI detectors operating in the 
regular mode with the energy range of about 80-800 keV (deposited energy). 
Only gamma-rays with energy greater than about 200 keV can penetrate 
the spacecraft and leave signals in the CsI detectors installed inside 
of the telescope. 

Insight-HXMT is the first Chinese space X-ray telescope, which was 
funded jointly by the China National Space Administration (CNSA) and 
the Chinese Academy of Sciences (CAS). 
More information about it could be found at: 
http://www.hxmt.org.


GRB_name: GRB200125A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26878
SUBJECT: GRB 200125A: Enhanced Swift-XRT position
DATE:    20/01/25 14:53:51 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 1010 s of XRT Photon Counting mode data and 3 UVOT
images for GRB 200125A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 228.04801, -8.14452 which is equivalent
to:

RA (J2000): 15h 12m 11.52s
Dec (J2000): -08d 08' 40.3"

with an uncertainty of 2.5 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB200125B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26879
SUBJECT: GRB 200125B: Fermi GBM Final Real-time Localization
DATE:    20/01/25 20:53:50 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 20:43:31 UT on 25 Jan 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200125B (trigger 601677816.188054 / 200125864).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 7.5, Dec = 64.7 (J2000 degrees, equivalent to J2000 00h 30m, 64d 42'), with a statistical uncertainty of 1.0 degrees.

The angle from the Fermi LAT boresight is 65.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200125864/quicklook/glg_skymap_all_bn200125864.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200125864/quicklook/glg_healpix_all_bn200125864.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200125864/quicklook/glg_lc_medres34_bn200125864.gif


GRB_name: GRB200125B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26880
SUBJECT: GRB 200125B: BALROG localization (Fermi Trigger 601677816 / GRB 200125864)
DATE:    20/01/25 21:20:59 GMT
FROM:    Jochen Greiner at MPE,Garching  <jcg@mpe.mpg.de>

B. Biltzinger, F. Kunzweiler, F. Berlato, J. Burgess & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
601677816 at 20:43:31 on 25 Jan. 2020 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).

The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 7.7+/-0.8 deg
Decl.(2000.0) = 64.4+/-0.4 deg
We estimate an additional systematic error of 2 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB200125864/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB200125864/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB200125864/json

                        


GRB_name: GRB200125A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26881
SUBJECT: Swift GRB 200125A: Global MASTER-Net observations report 
DATE:    20/01/26 00:56:23 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, 
V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva,
D.Kuvshinov,  D. Cheryasov
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile 
(Observatorio Astronomico Felix Aguilar OAFA),

H.Levato 
(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE),

R. Rebolo, M. Serra 
(The Instituto de Astrofisica de Canarias),

D. Buckley 
(South African Astronomical Observatory),

O.A. Gres, N.M. Budnev, O.Ershova 
(Irkutsk State University, API),

A. Tlatov, D. Dormidontov 
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich, Yu. Sergienko 
(Blagoveschensk Educational State University)




MASTER-SAAO robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in South Africa (South African Astronomical Observatory) was pointed to the Swift GRB 200125A ( A. Y. Lien et al., GCN 26876) errorbox  47603 sec after trigger time at 2020-01-26 00:45:02 UT, with upper limit up to  18.5 mag. The observations began at zenith distance = 71 deg. The sun  altitude  is -32.2 deg. 

The galactic latitude b = 40 deg., longitude l = 352 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1268985

We obtain a following upper limits.  

Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________

   47693 |         MASTER-SAAO |   C |   180 | 18.5 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.


GRB_name: GRB200125A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26882
SUBJECT: GRB 200125A: RATIR Optical Observations 
DATE:    20/01/26 01:39:15 GMT
FROM:    Alan M Watson at UNAM  <alan@astro.unam.mx>

Alan M. Watson (UNAM), Nat Butler (ASU), Alexander Kutyrev (GSFC),
William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J.
Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI),
Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz
(UCSC), JesÃºs GonzÃ¡lez (UNAM), Carlos RomÃ¡n-ZÃºÃ±iga (UNAM), Harvey
Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (U. Wash.), and Vicki
Toy (UMD) report:

We observed the field of GRB 200125A (Lien et al., GCN Circ. 26876) with
the Reionization and Transients Infrared Camera (RATIR; www.ratir.org)
on the 1.5m Harold Johnson Telescope at the Observatorio AstronÃ³mico
Nacional on Sierra San Pedro MÃ¡rtir from 2020/01 25.48 to 2020/01 25.56
UTC (0.03 to 1.89 hours after the BAT trigger), obtaining a total of
1.40 hours exposure in the r and i bands.

We detect a a source within the enhanced Swift-XRT error circle
(Beardmore et al., GCN Circ. 26878). In comparison with the USNO-B1 and
2MASS catalogs, we obtain the following detections:

  r = 21.02 +/- 0.05
  i = 19.54 +/- 0.02

These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.

We thank the staff of the Observatorio AstronÃ³mico Nacional in San Pedro
MÃ¡rtir.


GRB_name: GRB200125A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26883
SUBJECT: GRB 200125A: Nanshan-0.6m optical upper limit
DATE:    20/01/26 02:55:33 GMT
FROM:    Dong Xu at NAOC/CAS  <dxu@nao.cas.cn>

X. Liu, D. Xu, Z.P. Zhu, B.Y. Yu, Y. Ma (NAOC), X. Gao (Urumqi No.1 
Senior High School) report:

We observed the field of GRB 200125A (Lien et al., GCN 26876) using the 
NEXT-0.6m telescope located at Nanshan, Xinjiang, China. Observations 
started at 23:06:52 UT on 2020-01-25 (i.e., 11.59 h after the BAT 
trigger), and 10x300 s Sloan r-band frames were obtained.

No optical afterglow is detected within the enhanced Swift-XRT error 
circle (Beardmore et al., GCN Circ. 26878) in our stacked image, down to 
a limiting magnitude of r ~ 21.0, calibrated with the nearby PanSTARRS 
field.


GRB_name: GRB200125A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26884
SUBJECT: GRB 200125A: Swift-XRT refined Analysis
DATE:    20/01/26 11:44:06 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

A. Tohuvavohu (U. Toronto), J.A. Kennea (PSU), J.P. Osborne (U.
Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), A.
Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB), M.G. Bernardini
(INAF-OAB), B. Sbarufatti (PSU) and A.Y. Lien report on behalf of the
Swift-XRT team:

We have analysed 5.7 ks of XRT data for GRB 200125A (Lien et al. GCN
Circ. 26876), from 127 s to 28.1 ks after the  BAT trigger. The data
comprise 286 s in Windowed Timing (WT) mode with the remainder in
Photon Counting (PC) mode. The enhanced XRT position for this burst was
given by Beardmore et al. (GCN Circ. 26878). a rise, withpower-law
index .

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.523 (+/-0.029). The
best-fitting absorption column is  3.05 (+0.17, -0.16) x 10^21 cm^-2,
in excess of the Galactic value of 7.7 x 10^20 cm^-2 (Willingale et al.
2013). The PC mode spectrum has a photon index of 2.17 (+0.19, -0.18)
and a best-fitting absorption column of 1.3 (+0.5, -0.4) x 10^21 cm^-2.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum  is 3.1 x 10^-11 (4.2 x 10^-11) erg cm^-2
count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      1.3 (+0.5, -0.4) x 10^21 cm^-2
Galactic foreground: 7.7 x 10^20 cm^-2
Excess significance: 2.0 sigma
Photon index:      2.17 (+0.19, -0.18)

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00952164.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB200125A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26885
SUBJECT: Correction to GRB 200125A: Swift-XRT refined analysis
DATE:    20/01/26 11:59:01 GMT
FROM:    Kim Page at U.of Leicester  <klp5@leicester.ac.uk>

K.L. Page reports on behalf of the Swift-XRT team:

The automated Swift-XRT refined analysis circular (GCN Circ. 26884)
provided an incomplete description of the X-ray light-curve of GRB
200125A. The PC mode data collected between 10 and 28 ks show an
approximately constant count rate of ~0.15 count s^-1. We therefore do not
give a prediction for T+24 hours.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00952164.

This circular is an official product of the Swift-XRT team.

[GCN OPS NOTE(26jan20): Per author's request, the url was corrected
from http://www.swift.ac.uk/xrt_products/00950330
to   http://www.swift.ac.uk/xrt_products/00952164.]


GRB_name: GRB200125A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26887
SUBJECT: GRB 200125A: TNG detection of a NIR counterpart candidate
DATE:    20/01/26 13:33:30 GMT
FROM:    Paolo D'Avanzo at INAF-OAB  <pda.davanzo@gmail.com>

A. Melandri, P. D'Avanzo (INAF-OAB), V. Dâ€™Elia (ASI-SSDC), W. Boschin, G. Mainella (INAF-TNG) 
on behalf of the CIBO collaboration report:

We observed the field of GRB 200125A (Lien et al., GCN Circ. 26876) with the Italian 3.58m TNG telescope 
equipped with NICS in imaging mode. A series of images were obtained with the Ks and J filters on 2020-01-26 
from 05:25 to 06:39 UT (i.e. from about 17.9 to 19.1 hours after the burst). 

We detect a source at the following coordinates: 

RA(J2000), Dec (J2000) = 15:12:11.30, -08:08:38.5  (+/- 0.5â€).

This position is consistent with the most updated XRT localisation (https://www.swift.ac.uk/xrt_positions/ <https://www.swift.ac.uk/xrt_positions/>). We assume 
this is the same source detectd in the optical by Watson et al. (GCN Circ. 26882). 

From preliminary photometry, we estimate for this object a magnitude Ks ~ 17.2 (Vega, calibrated assuming K = 12.1 
for the 2MASS star at RA(J2000), Dec (J2000) = 15:12:05.10, -08:07:06.9).  

[GCN OPS NOTE(26jan20): Per OPS, the Circular referenced in the first sentence (26976) was changed to 26876).]


GRB_name: GRB200125B
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26888
SUBJECT: GRB 200125B: Insight-HXMT/HE detection
DATE:    20/01/26 14:10:22 GMT
FROM:    Ce Cai at IHEP  <caice@ihep.ac.cn>

C. Cai, S. Xiao, Y. F. Du, Y. G. Zheng, Q. Luo, Q. B. Yi, 
Y. Huang, C. K. Li, G. Li, X. B. Li, J. Y. Liao, S. L. Xiong,
C. Z. Liu, X. F. Li, Z. W. Li, Z. Chang, A. M. Zhang, 
Y. F. Zhang, X. F. Lu, C. L. Zou (IHEP), Y. J. Jin, 
Z. Zhang (THU), T. P. Li (IHEP/THU), F. J. Lu, L. M. Song, 
M. Wu, Y. P. Xu, S. N. Zhang (IHEP), 
report on behalf of the Insight-HXMT team:

At 2020-01-25T20:43:31.90 (T0), Insight-HXMT/HE detected 
GRB 200125B (trigger ID: HEB200125863) in a routine search of the data, 
which also triggered Fermi/GBM (GCN #26879).

The Insight-HXMT/HE light curve mainly consists of multiple 
pulses with a duration (T90) of 4.66 s measured from T0-0.11 s. 
The 1-ms peak rate, measured from T0+0.57 s, is 9038 cnts/sec. 
The total counts from this burst is 18553 counts. 
URL_LC: http://www.hxmt.org/images/GRB/HEB200125863_lc.jpg 

All measurements above are made with the CsI detectors operating in the 
regular mode with the energy range of about 80-800 keV (deposited energy). 
Only gamma-rays with energy greater than about 200 keV can penetrate 
the spacecraft and leave signals in the CsI detectors installed inside 
of the telescope. 

Insight-HXMT is the first Chinese space X-ray telescope, which was 
funded jointly by the China National Space Administration (CNSA) and 
the Chinese Academy of Sciences (CAS). 
More information about it could be found at: 
http://www.hxmt.org.


GRB_name: GRB200125A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26889
SUBJECT: GRB 200125A: AbAO optical upper limit
DATE:    20/01/26 18:25:59 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

S. Belkin (IKI), A. Pozanenko (IKI), R. Ya. Inasaridze (AbAO ), E. 
Mazaeva (IKI), A. Volnova (IKI),  V. R. Ayvazian  (AbAO ), G.V. 
Kapanadze (AbAO), I. Molotov (KIAM) report on behalf of larger IKI GRB 
follow-up collaboration:

We observed  GRB 200125A (Lien et al., GCN 26876) with AS-32 (0.7m) 
telescope of Abastumani Observatory starting on Jan. 26 (UT) 01:32:27. 
We obtained several 60 s exposures  in R-filter. We do not detect any 
source within enhanced Swift-XRT position (Beardmore et al., GCN 26878) 
in the stacked image. In particular we do not detect counterpart 
candidate (Watson et al., GCN 26882;  Melandri et al., GCN 26887)
Photometry of the field  is following

Date       UT start t-T0    Filter Exp.  OT    Err. UL(3sigma)
                    (mid, days)     (s)

2020-01-26 01:32:27 0.520   R      56*60 n/d   n/d  21.2

Photometry is based on nearby USNO-B1.0 stars (R2 magnitude):

USNO-B1.0_id R2
0818-0339924 16.46
0818-0339917 16.94


GRB_name: GRB200125A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26891
SUBJECT: GRB 200125A: Further RATIR Optical Observations and Confirmation of Fading
DATE:    20/01/26 21:08:51 GMT
FROM:    Alan M Watson at UNAM  <alan@astro.unam.mx>

Alan M. Watson (UNAM), Nat Butler (ASU), Alexander Kutyrev (GSFC),
William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J.
Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI),
Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz
(UCSC), JesÃºs GonzÃ¡lez (UNAM), Carlos RomÃ¡n-ZÃºÃ±iga (UNAM), Harvey
Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (U. Wash.), and Vicki
Toy (UMD) report:

We observed the field of GRB 200125A (Lien et al., GCN Circ. 26876) with
the Reionization and Transients Infrared Camera (RATIR; www.ratir.org)
on the 1.5m Harold Johnson Telescope at the Observatorio AstronÃ³mico
Nacional on Sierra San Pedro MÃ¡rtir from 2020/01 26.42 to 2020/01 26.56
UTC (22.62 to 25.89 hours after the BAT trigger), obtaining a total of
2.52 hours exposure in the r and i bands.

The source we reported previously (Watson et al., GCN Circ. 26882) has
faded, confirming that it is the afterglow. In comparison with the
USNO-B1 and 2MASS catalogs, we obtain the following detections:

  r = 23.03 +/- 0.29
  i = 21.27 +/- 0.05

These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.

We thank the staff of the Observatorio AstronÃ³mico Nacional in San Pedro 
MÃ¡rtir.


GRB_name: GRB200125A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26892
SUBJECT: GRB 200125A: Swift/UVOT Upper Limits
DATE:    20/01/27 01:22:25 GMT
FROM:    Kira Simpson at PSU  <kira.simpson1984@gmail.com>

GRB 200125A: Swift/UVOT Upper Limits

K. K. Simpson (PSU) and A. Y. Lien (GSFC/UMBC)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 200125A
179 s after the BAT trigger (Lien et al., GCN Circ. 26876).
No optical afterglow consistent with the XRT position
(Beardmore et al. GCN Circ. 26878)
is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC           179          329          147         >20.4
white              179         4176          344         >21.1
v                 4387         4586          197         >18.4
b                 3771         3971          197         >19.9
u                  337          414           75         >18.9
w1                4796         4835           38         >18.6
m2                4591         4791          197         >19.3
w2                4182         4382          197         >20.2

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.08 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB200125B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26893
SUBJECT: GRB 200125B: Fermi GBM observations
DATE:    20/01/27 02:06:37 GMT
FROM:    Peter Veres at UAH  <veresp@gmail.com>

P. Veres, S. Poolakkil and C. Meegan (all UAH)
report on behalf of the Fermi GBM Team:

"At 20:43:31.19 UT on 25 January 2020, the Fermi Gamma-Ray Burst Monitor
(GBM) triggered and located GRB 200125B
(trigger 601677816 / 200125864) (Fermi GBM Team, GCN #26879),
which was also detected by Insight-HXMT/HE (Cai et al., GCN #26888).

The GBM light curve consists of multiple overlapping pulses
with a duration (T90) of about 5.8 s (50-300 keV).
The time-averaged spectrum from T0 s to T0+12 s is
best fit by a Band function with Epeak = 175 +/- 3 keV,
alpha = -0.74 +/- 0.01, and beta = -2.23 +/- 0.02.

The event fluence (10-1000 keV) in this time interval is
(5.48 +/- 0.03)E-5 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+1.3 s in the 10-1000 keV band
is 103.7 +/- 0.6 ph/s/cm^2.


The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support
Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB200125A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26894
SUBJECT: GRB 200125A: Further Swift-XRT observations
DATE:    20/01/27 08:39:42 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P.A. Evans, K.L. Page (U. Leicester) and A.Y. Lien (GSFC/UMBC) report on behalf of the Swift-XRT team:

We provide an update on the XRT light curve evolution of GRB 200125A (GCN Circs. 26876 and 26885). 

The XRT light curve shows early, strong flaring activity which is interrupted at T0+414 s as the GRB went into Earth eclipse; by the time of the next observation (T0+3.8 ks) the light curve had faded by 4 orders of magnitude to ~0.1 ct/sec (2e-12 erg cm^-2 s^-1; 0.3-10 keV). It has remained approximately at this level, with some small variation, until our most recent data point at T0+113 ks (=T0+1.3 d). This suggests a very long-lived â€˜plateauâ€™ phase. Such long-duration plateaux are rare but not unique. Due to the expectation of a break at some, unknown point in the (probably) near future, we are unable to predict what the flux will be over the coming days. Observations are ongoing. The latest results can be viewed via: https://www.swift.ac.uk/xrt_products/00952164/

This circular is an official product of the Swift-XRT team.


GRB_name: GRB200127A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26895
SUBJECT: GRB 200127A: Swift detection of a burst
DATE:    20/01/27 15:04:17 GMT
FROM:    Caryl Gronwall at PSU/Swift-UVOT  <caryl@swift.psu.edu>

M. J. Moss (GWU), A. P. Beardmore (U Leicester),
P. A. Evans (U Leicester), C. Gronwall (PSU), J.D. Gropp (PSU),
J. A. Kennea (PSU), N. J. Klingler (PSU), A. Y. Lien (GSFC/UMBC),
F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester),
M. H. Siegel (PSU) and A. Tohuvavohu (U Toronto) report on behalf of
the Neil Gehrels Swift Observatory Team:

At 14:44:31 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 200127A (trigger=952791).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 295.204, +44.910 which is 
   RA(J2000) = 19h 40m 49s
   Dec(J2000) = +44d 54' 35"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  As is usual with an image trigger, the available
BAT light curve shows no significant structure. 

The XRT began observing the field at 14:46:52.1 UT, 140.5 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source located at RA, Dec 295.19447,
44.90030 which is equivalent to:
   RA(J2000)  = 19h 40m 46.67s
   Dec(J2000) = +44d 54' 01.1"
with an uncertainty of 3.5 arcseconds (radius, 90% containment). This
location is 42 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at https://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 2.17
x 10^21 cm^-2 (Willingale et al. 2013). 

The initial flux in the 2.5 s image was 9.40e-10 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 250 seconds with the U filter starting
309 seconds after the BAT trigger. No credible afterglow candidate has been
found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the
XRT error circle. The typical 3-sigma upper limit has been about 19.2 mag. The
8'x8' region for the list of sources generated on-board covers 100% of the XRT
error circle. The list of sources is typically complete to about 18.0 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.16. 

Burst Advocate for this burst is M. J. Moss (mikejmoss3 AT gmail.com). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB200125A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26897
SUBJECT: GRB 200125A: Swift-BAT refined analysis
DATE:    20/01/27 18:18:42 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), H. A. Krimm (NSF),
S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC),
D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU), T. N. Ukwatta (LANL)
(i.e. the Swift-BAT team):

Using the data set from T-170 to T+808 sec from the recent telemetry
downlink,
we report further analysis of BAT GRB 200125A (trigger #952164)
(Lien et al., GCN Circ. 26876).  The BAT ground-calculated position is
RA, Dec = 228.069, -8.142 deg which is
   RA(J2000)  =  15h 12m 16.6s
   Dec(J2000) = -08d 08' 31.3"
with an uncertainty of 1.8 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 42%.

The mask-weighted light curve shows a multi-pulse structure that starts
at ~T-40 s and ends at ~T+430 s. The three main pulses occurs at ~T0,
~T+200 s, and ~T+300 s, respectively. The highest peak is at ~T+287 s.
The burst went out of the BAT FOV at T+501 s. T90 (15-350 keV)
is 350.83 +- 34.03 sec (estimated error including systematics).

The time-averaged spectrum from T-36.22 to T+427.74 sec is best fit by a
simple
power-law model.  The power law index of the time-averaged spectrum is
1.95 +- 0.08.  The fluence in the 15-150 keV band is 8.7 +- 0.4 x 10^-6
erg/cm2.
The 1-sec peak photon flux measured from T+286.67 sec in the 15-150 keV band
is 4.0 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/952164/BA/


GRB_name: GRB200127B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26898
SUBJECT: GRB 200127B: Fermi GBM Final Real-time Localization
DATE:    20/01/27 18:21:40 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 18:11:18 UT on 27 Jan 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200127B (trigger 601841483.670522 / 200127758).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 75.9, Dec = 20.1 (J2000 degrees, equivalent to J2000 05h 03m, 20d 06'), with a statistical uncertainty of 3.3 degrees.

The angle from the Fermi LAT boresight is 55.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200127758/quicklook/glg_skymap_all_bn200127758.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200127758/quicklook/glg_healpix_all_bn200127758.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200127758/quicklook/glg_lc_medres34_bn200127758.gif


GRB_name: GRB200127A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26899
SUBJECT: GRB 200127A: AbAO optical upper limit
DATE:    20/01/27 18:59:15 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

S. Belkin (IKI), A. Pozanenko (IKI), R. Ya. Inasaridze (AbAO ),  V. R. 
Ayvazian  (AbAO ), G.V. Kapanadze (AbAO), E. Mazaeva (IKI), A. Volnova 
(IKI), I. Molotov (KIAM) report on behalf of larger IKI GRB follow-up 
collaboration:

We observed  the GRB 200127A (Moss et al., GCN 26895) with AS-32 (0.7m) 
telescope of Abastumani Observatory starting on Jan. 27 (UT) 15:09:06. 
We obtained several 60 s exposures  in R-filter. We do not detect any 
source within  Swift-XRT position (Moss et al., GCN 26895).
Preliminary photometry of the field  is following

Date       UT start t-T0    Filter Exp.  OT    Err. UL(3sigma)
                    (mid, days)     (s)

2020-01-27 15:09:06 0.02922 R      35*60 n/d   n/d  20.4

Photometry is based on nearby USNO-B1.0 stars (R2 magnitude):

USNO-B1.0_id R2
1349-0340354 14.16
1349-0343444 15.86


GRB_name: GRB200127A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26901
SUBJECT: GRB 200127A: Swift-XRT refined Analysis
DATE:    20/01/27 23:51:22 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J.A. Kennea (PSU), K.L. Page (U. Leicester), A.P. Beardmore (U.
Leicester), P.A. Evans (U. Leicester), P. D'Avanzo (INAF-OAB), M.G.
Bernardini (INAF-OAB), E. Ambrosi  (INAF-IASFPA) , B. Sbarufatti (PSU),
D.N. Burrows (PSU) and M.J. Moss report on behalf of the Swift-XRT
team:

We have analysed 8.3 ks of XRT data for GRB 200127A (Moss et al. GCN
Circ. 26895), from 130 s to 18.2 ks after the  BAT trigger. The data
comprise 215 s in Windowed Timing (WT) mode (the first 9 s were taken
while Swift was slewing) with the remainder in Photon Counting (PC)
mode. The refined XRT position is RA, Dec = 295.1933, +44.9008 which is
equivalent to:

RA (J2000): 19 40 46.40
Dec(J2000): +44 54 02.8

with an uncertainty of 3.5 arcsec (radius, 90% confidence).

The light curve can be modelled with a series of power-law decays. The
initial decay index is alpha=1.1 (+0.6, -2.6). At T+172 s  the decay
steepens to an alpha of 2.58 (+0.18, -0.15) before breaking again at
T+648 s to a final decay with index alpha=1.32 (+0.09, -0.12).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.98 (+0.05, -0.04). The
best-fitting absorption column is  consistent with the Galactic value
of 2.2 x 10^21 cm^-2 (Willingale et al. 2013). The PC mode spectrum has
a photon index of 1.75 (+0.12, -0.11) and a best-fitting absorption
column consistent with the Galactic value. The counts to observed
(unabsorbed) 0.3-10 keV flux conversion factor deduced from this
spectrum  is 4.1 x 10^-11 (5.1 x 10^-11) erg cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      2.2 (+0.3, -0.0) x 10^21 cm^-2
Galactic foreground: 2.2 x 10^21 cm^-2
Excess significance: <1.6 sigma
Photon index:      1.75 (+0.12, -0.11)

If the light curve continues to decay with a power-law decay index of
1.32, the count rate at T+24 hours will be 1.8 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 7.6 x
10^-14 (9.4 x 10^-14) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00952791.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB200127A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26902
SUBJECT: GRB 200127A: Enhanced Swift-XRT position
DATE:    20/01/28 00:01:49 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 7439 s of XRT Photon Counting mode data and 12 UVOT
images for GRB 200127A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 295.19300, +44.90029 which is equivalent
to:

RA (J2000): 19h 40m 46.32s
Dec (J2000): +44d 54' 01.0"

with an uncertainty of 1.4 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB200127A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26904
SUBJECT: GRB 200127A: Nanshan-0.6m optical upper limit
DATE:    20/01/28 02:37:47 GMT
FROM:    Dong Xu at NAOC/CAS  <dxu@nao.cas.cn>

X. Liu, D. Xu, Z.P. Zhu, B.Y. Yu, Y. Ma (NAOC), X. Gao (Urumqi No.1 
Senior High School) report:

We observed the field of GRB 200127A (Moss et al., GCN 26895) using the 
NEXT-0.6m telescope located at Nanshan, Xinjiang, China. Observations 
started at 23:26:58 UT on 2020-01-27 (i.e., 8.71 h after the BAT 
trigger), and 7x300 s Sloan r-band frames were obtained.

No optical afterglow is detected within the enhanced Swift-XRT error 
circle (Evans et al., GCN 26902) in our stacked image, down to a 
limiting magnitude of r ~ 20.5, calibrated with the nearby PanSTARRS field.


GRB_name: GRB200128A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26909
SUBJECT: GRB 200128A: Fermi GBM Final Real-time Localization
DATE:    20/01/28 03:50:27 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely SHORT GRB

At 03:40:05 UT on 28 Jan 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200128A (trigger 601875610.774992 / 200128153).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 158.6, Dec = 41.6 (J2000 degrees, equivalent to J2000 10h 34m, 41d 36'), with a statistical uncertainty of 19.0 degrees.

The angle from the Fermi LAT boresight is 129.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200128153/quicklook/glg_skymap_all_bn200128153.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200128153/quicklook/glg_healpix_all_bn200128153.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200128153/quicklook/glg_lc_medres34_bn200128153.gif


GRB_name: GRB200125B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26911
SUBJECT: GRB 200125B: DDOTI/OAN  optical observations report
DATE:    20/01/28 06:04:23 GMT
FROM:    Emma Margarita Pereyra Talamantes at IA-UNAM Ensenada  <mpereyra@astro.unam.mx>

Margarita Pereyra (UNAM), Nat Butler (ASU), Alan M. Watson (UNAM),
 Eleonora Troja (GSFC/UMD),  Diego Gonzalez (UNAM), Alexander Kutyrev
(GSFC/UMD), William H. Lee (UNAM), and Tanner Wolfram (ASU), Simone
Dichiara (GSFC/UMD) report:

We observed the field of GRB 200125B detected by Fermi Gamma-ray Burst
Monitor (Fermi GBM Team, GCN Circ. 26879, Veres et al., GCN Circ. 26893),
with the DDOTI/OAN wide-field imager at the Observatorio AstronÃ³mico
Nacional on Sierra San Pedro MÃ¡rtir (http://ddoti.astroscu.unam.mx) from
2020-01-26 02:18 to 2020-01-26 06:53 UTC (5.58 to 10.16 hours after the
event).

We observed a region of 6.8 degrees in RA by 10.2 degrees in declination
centered on the GBM Final Position 00:29:47 +64:41:22 J2000. This region
contains about 70 square degrees. We obtained about 3.1 hrs total exposure
across the region.

We calibrated our images against the APASS catalog. Our 10-sigma limiting
magnitude is w = 20.04 for a 2.0 degrees radius error region centered at
the GBM Final Position. Comparing to the USNO-B1 and PAN-STARRS DR1
catalogs we do not detect any uncataloged source with significant fading or
rising to our 10-sigma limit.

We thank the staff of the Observatorio AstronÃ³mico Nacional in San Pedro
MÃ¡rtir.
-- 
*Dr. Margarita Pereyra *

*FFTF, Schlumberger Foundation Alumnae*
----------------------------------------------------------------------------------------------------------------

*CatedrÃ¡tico Conacyt*

*Instituto de AstronomÃ­a de la UNAM,*

*Km. 107 Carretera Tijua**na-Ensenada, *

*Ensenada Baja California, MÃ©xico. C.P. 22860*

Oficina: 405

Skype: margarita-pereyra


GRB_name: GRB200127A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26913
SUBJECT: GRB200127A: Nordic Optical telecope optical upper limit
DATE:    20/01/28 10:21:58 GMT
FROM:    Johan Fynbo at Neils Bohr Institute  <jfynbo@nbi.ku.dk>

Johan P. U. Fynbo (DAWN/NBI), Daniele B. Malesani (DTU Space), Kasper E. Heintz (Univ. Iceland), Luca Izzo (DARK/NBI), Amanda Djupvik (NOT), report on behalf of a larger collaboration:

On 2020 Jan 28.292 UT (16.274 hr after the GRB) we observed the field of GRB200127A (Moss et al., GCN 26895; Evans et al., GCN26902) with the Nordic Optical Telescope in the SDSS r-filter for a total integration time of 900 s. Within the XRT position, we find no evidence for afterglow emission above a 3-sigma limit of about 23 mag AB, calibrated against field stars from the PAN-STARRS catalog.


GRB_name: GRB200127A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26914
SUBJECT: GRB 200127A: Mondy optical upper limit
DATE:    20/01/28 10:35:13 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

S. Belkin (IKI), A. Pozanenko (IKI), E. Klunko (ISTP), E. Mazaeva (IKI), 
A. Volnova (IKI) report on behalf of IKI-GRB-FuN:

We observed the field of GRB 200127A (Moss et al., GCN 26895) with 
AZT-33IK telescope of Sayan observatory (Mondy) starting on Jan. 27
(UT) 21:48:01. We do not detect any optical object within Enhanced 
Swift-XRT position (Evans et al., GCN 26902) in agreement with 
non-detection of an afterglow (Liu et al., GCN 26904; Fynbo et al., GCN 
26913). Preliminary photometry of the field is following.

Date UT start       t-T0,   Filter Exp.,  OT  Err  UL(3sigma)
                     (days)         (s)
2020-01-27 21:48:01 0.30868 R      21*120 n/d n/d  22.8

Photometry is based on the USNO-B1.0 nearby stars.
USNO-B1.0    R2
1349-0340555 18.02
1349-0340544 17.39


GRB_name: GRB200128B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26917
SUBJECT: GRB 200128B: AGILE/MCAL detection of a burst
DATE:    20/01/28 15:31:14 GMT
FROM:    Alessandro Ursi at INAF/IAPS  <alessandro.ursi@gmail.com>

A. Ursi (INAF/IAPS), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), M.
Cardillo, C. Casentini, G. Piano (INAF/IAPS), F. Lucarelli, C. Pittori, F.
Verrecchia (SSDC, and INAF/OAR), A. Bulgarelli, V. Fioretti, N. Parmiggiani
(INAF/OAS-Bologna), M. Pilia (INAF/OA-Cagliari), F. Longo (Univ. Trieste
and INFN Trieste), report on behalf of the AGILE Team:

The AGILE mini-calorimeter (MCAL) detected a short hard burst at T0 =
2020-01-28 12:23:29.98 +/- 0.01 s (UTC).

The event triggered the 64 ms MCAL logic timescale and lasted about 0.10 s,
releasing a total number of ~90 counts in the detector (in the 0.4-100 MeV
energy range), above an average background rate of ~500 counts / s.

The light curve shows a single peak and can be found at
http://www.agilescienceapp.it/notices/GRB_066265_507299009.979947.png.

The AGILE-MCAL detector is a CsI detector with a 4 pi FoV, sensitive in the
energy range 0.4-100 MeV. Additional analysis of AGILE data is in progress.


GRB_name: GRB200125B
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26918
SUBJECT: IPN triangulation of GRB 200125B
DATE:    20/01/28 16:20:12 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, A. Ridnaia,
and T. Cline on behalf of the Konus-Wind team,

K. Hurley, on behalf of the IPN,

A. Goldstein, M. S. Briggs, and C. Wilson-Hodge
on behalf of the Fermi GBM team, and

S. Xiao, C. K. Li, X. B. Li, Y. Huang, and S. L. Xiong
on behalf of the Insight-HXMT/HE GRB team, report:

The long-duration, very bright GRB 200125B
(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 26879;
BALROG localization: Biltzinger et al., GCN Circ. 26880;
Insight-HXMT/HE detection: Cai et al., GCN Circ. 26888)
was detected by Fermi (GBM trigger 601677816), Konus-Wind,
and Insight (HXMT/HE) at about 74611 s UT (20:43:31).

We have triangulated this GRB to a Konus-GBM annulus centered at
RA(2000)=321.900 deg (21h 27m 36s) Dec(2000)=-14.917 deg (-14d 55' 02")
whose radius is 86.537 +/- 0.136 deg (3 sigma) and a wider
Konus-HXMT annulus.

These annuli may be improved.

The annulus is consistent with, but reduces
the area of, the final Fermi-GBM (GCN Circ. 26879) and
BALROG (GCN Circ. 26880) localizations.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB200125_T74611/IPN/

The Konus-Wind time history and spectrum will be given in a forthcoming
GCN Circular.


GRB_name: GRB200127A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26919
SUBJECT: GRB 200127A: Swift/UVOT Upper Limits
DATE:    20/01/28 19:11:13 GMT
FROM:    Mike Siegel at PSU/Swift MOC  <mhs18@psu.edu>

A. Belles (PSU) and M. J. Moss (GWU)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 200127A
150 s after the BAT trigger (Moss et al., GCN Circ. 26895).
No optical afterglow consistent with the XRT position (Evans et al.,
GCN Circ. 26902) is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC           150          300          147         >20.4
u_FC               310          560          246         >19.4
white              150        11742         1368         >22.3
v                  640        16568         1317         >20.2
b                  566        10830         1121         >21.3
u                  310         6701          638         >20.2
w1                 690        18173         1095         >21.1
m2                 838        17473         1298         >20.6
w2                 615        12437         1110         >20.5

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.16 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB200129A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26932
SUBJECT: GRB 200129A: Fermi GBM Final Real-time Localization
DATE:    20/01/29 09:59:05 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely SHORT GRB

At 09:48:44 UT on 29 Jan 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200129A (trigger 601984129.18217 / 200129409).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 346.3, Dec = -45.0 (J2000 degrees, equivalent to J2000 23h 05m, -45d 00'), with a statistical uncertainty of 13.1 degrees.

The angle from the Fermi LAT boresight is 111.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200129409/quicklook/glg_skymap_all_bn200129409.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200129409/quicklook/glg_healpix_all_bn200129409.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200129409/quicklook/glg_lc_medres34_bn200129409.gif


GRB_name: GRB200125A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26935
SUBJECT: Konus-Wind observation of GRB 200125A
DATE:    20/01/29 14:55:46 GMT
FROM:    Anna Ridnaia at Ioffe Institute  <ridnaia@mail.ioffe.ru>

A. Ridnaia, S. Golenetskii, R. Aptekar, D. Frederiks,
M. Ulanov, D. Svinkin, A. Tsvetkova, A.Lysenko,
and T. Cline on behalf of the Konus-Wind team, report:

The long GRB 200125A (Swift-BAT trigger #952164:
Lien et al., GCN 26876; Markwardt et al., GCN 26897)
was detected by Konus-Wind in the waiting mode.

The burst light curve shows three emission pulses
in the interval from ~T0(BAT)-35 s to ~T0(BAT)+315 s.

The K-W light curve of this burst is available at
http://www.ioffe.rssi.ru/LEA/GRBs/GRB200125A/

As observed by Konus-Wind, the burst had a fluence of
2.04(-0.16,+0.22)x10^-5 erg/cm2 and a 2.944-s peak flux,
measured from ~T0(BAT)+287.4 s, of 2.80(-0.58,+0.62)x10^-7 erg/cm2/s
(both in the 20 - 1500 keV energy range).

The K-W 3-channel time-integrated spectrum
(from ~T0(BAT)-33.5 s to ~T0(BAT)+316.8 s)
is best described by simple power-law model
with photon index of -2.14(-0.09,+0.1), chi2=0.08/1 dof.

All the quoted errors are estimated at the 1 sigma confidence level.
All the presented results are preliminary.


GRB_name: GRB200127A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26939
SUBJECT: GRB 200127A: Swift-BAT refined analysis
DATE:    20/01/29 22:48:04 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

D. M. Palmer (LANL), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), H. A. Krimm (NSF),
S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), M. J. Moss (GWU)
T. Sakamoto (AGU), M. Stamatikos (OSU),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-240 to T+1079 sec from the recent telemetry
downlink,
we report further analysis of BAT GRB 200127A (trigger #952791)
(Moss et al., GCN Circ. 26895).  The BAT ground-calculated position is
RA, Dec = 295.206, 44.934 deg which is
   RA(J2000)  =  19h 40m 49.4s
   Dec(J2000) = +44d 56' 03.5"
with an uncertainty of 2.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 50%.

The mask-weighted light curve shows a long weak emission that starts
around ~T-150 s and ends at ~T+90 s. T90 (15-350 keV) is 216.9 +- 23.5 sec
(estimated error including systematics).

The time-averaged spectrum from T-144.22 to T+92.97 sec is best fit by a
simple
power-law model.  The power law index of the time-averaged spectrum is
1.64 +- 0.19.  The fluence in the 15-150 keV band is 2.4 +- 0.3 x 10^-6
erg/cm2.
The 1-sec peak photon flux measured from T+41.80 sec in the 15-150 keV band
is 0.7 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/952791/BA/


GRB_name: GRB200130A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26942
SUBJECT: GRB 200130A: Fermi GBM Final Real-time Localization
DATE:    20/01/30 06:07:39 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 05:57:16 UT on 30 Jan 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200130A (trigger 602056641.079094 / 200130248).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 329.3, Dec = -65.9 (J2000 degrees, equivalent to J2000 21h 57m, -65d 54'), with a statistical uncertainty of 1.7 degrees.

The angle from the Fermi LAT boresight is 7.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200130248/quicklook/glg_skymap_all_bn200130248.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200130248/quicklook/glg_healpix_all_bn200130248.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200130248/quicklook/glg_lc_medres34_bn200130248.gif


GRB_name: GRB200130B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26944
SUBJECT: GRB 200130B: Fermi GBM Final Real-time Localization
DATE:    20/01/30 10:10:17 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 09:59:56 UT on 30 Jan 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200130B (trigger 602071201.67246 / 200130417).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 137.5, Dec = -51.3 (J2000 degrees, equivalent to J2000 09h 09m, -51d 17'), with a statistical uncertainty of 3.5 degrees.

The angle from the Fermi LAT boresight is 34.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200130417/quicklook/glg_skymap_all_bn200130417.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200130417/quicklook/glg_healpix_all_bn200130417.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200130417/quicklook/glg_lc_medres34_bn200130417.gif


GRB_name: GRB200130B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26945
SUBJECT: GRB 200130B: BALROG localization (Fermi Trigger 602071201 / GRB 200130417)
DATE:    20/01/30 10:35:00 GMT
FROM:    Jochen Greiner at MPE,Garching  <jcg@mpe.mpg.de>

F. Kunzweiler, B. Biltzinger, F. Berlato, J. Burgess & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
602071201 at 09:59:56 on 30 Jan. 2020 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).

The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 138.5+/-1.4 deg
Decl.(2000.0) = -56.9+/-0.9 deg
We estimate an additional systematic error of 2 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB200130417/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB200130417/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB200130417/json

                        


GRB_name: GRB200130B
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26949
SUBJECT: IPN triangulation of GRB 200130B
DATE:    20/01/31 12:15:53 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

K. Hurley, on behalf of the IPN,

I. G. Mitrofanov, D. V. Golovin, A. S. Kozyrev, M. L. Litvak,
and A. B. Sanin, on behalf of the HEND-Odyssey GRB team,

D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, A. Ridnaia,
and T. Cline on behalf of the Konus-Wind team,

A. Goldstein, M. S. Briggs, and C. Wilson-Hodge
on behalf of the Fermi GBM team,

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,

S. Barthelmy, J. Cummings, H. Krimm, and D. Palmer,
on behalf of the Swift-BAT team, and

W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr,
on behalf of the GRS-Odyssey GRB team, report:

The long-duration GRB 200130B
(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 26944;
BALROG localization: Kunzweiler et al., GCN Circ. 26945)
was detected by Fermi (GBM trigger 602071201), Konus-Wind,
INTEGRAL (SPI-ACS), Mars-Odyssey (HEND), and Swift (BAT),
at about 35997 s UT (09:59:57).
The burst was outside the coded field of view of the BAT.

We have triangulated it to a preliminary, 3 sigma error box
whose coordinates are:
  ---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
   134.742 (08h 58m 58s) -49.627 (-49d 37' 38")
  Corners:
   133.618 (08h 54m 28s) -50.349 (-50d 20' 55")
   134.000 (08h 56m 00s) -50.392 (-50d 23' 31")
   135.836 (09h 03m 21s) -48.893 (-48d 53' 34")
   135.462 (09h 01m 51s) -48.857 (-48d 51' 26")
  ---------------------------------------------
The error box area is 1487 sq. arcmin, and its maximum
dimension is 2.0 deg (the minimum one is 13 arcmin).
The Sun distance was 112 deg.

This box may be improved.

The IPN localization is consistent with, but reduces the area of, the 
Fermi-GBM final position (GCN Circ. 26944).

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB200130_T35999/IPN

The Konus-Wind time history and spectrum will be given in a forthcoming
GCN Circular.


GRB_name: GRB200130B
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26950
SUBJECT: Konus-Wind observation of GRB 200130B
DATE:    20/01/31 16:08:04 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks,
M. Ulanov, A. Tsvetkova, A. Lysenko, A. Ridnaia, and T. Cline
on behalf of the Konus-Wind team, report:

The long-duration GRB 200130B
(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 26944;
BALROG localization: Kunzweiler et al., GCN Circ. 26945;
IPN triangulation: Hurley et al., GCN Circ. 26949)
triggered Konus-Wind at T0=35999.282 s UT (09:59:59.282).

The burst light curve shows an initial intense pulse
which starts at ~T0-0.3 s followed by a weaker emission up to ~12 s.
The emission is seen up to ~1 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB200130_T35999/

As observed by Konus-Wind, the burst
had a fluence of 1.10(-0.09,+0.11)x10^-5 erg/cm2,
and a 64-ms peak flux, measured from T0+0.284 s,
of 6.59(-1.21,+1.34)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum of the burst
(measured from T0 to T0+16.640 s)
is best fit in the 20 keV - 1 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.88(-0.19,+0.24),
the high energy photon index beta = -3.58(-6.42,+0.64),
the peak energy Ep = 90(-6,+6) keV
(chi2 = 55/44 dof).

The spectrum near the maximum count rate
(measured from T0+0.256 to T0+8.448 s)
is best fit in the 20 keV - 1 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.85(-0.20,+0.26),
the high energy photon index beta = -4.01(-5.99,+0.98),
the peak energy Ep = 91(-6,+6) keV
(chi2 = 44/44 dof).

All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.


GRB_name: GRB200125B
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26951
SUBJECT: Konus-Wind observation of GRB 200125B
DATE:    20/01/31 16:11:49 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks,
M. Ulanov, A. Tsvetkova, A. Lysenko, A. Ridnaia, and T. Cline
on behalf of the Konus-Wind team, report:

The long-duration, very bright GRB 200125B
(Fermi-GBM observations: The Fermi GBM team, GCN Circ. 26879;
Veres et al., GCN Circ. 26893;
BALROG localization: Biltzinger et al., GCN Circ. 26880;
Insight-HXMT/HE detection: Cai et al., GCN Circ. 26888;
IPN triangulation: Svinkin et al., GCN Circ. 26918)
triggered Konus-Wind at T0=74611.206 s UT (20:43:31.206).

The burst light curve shows a multipeaked structure
which starts at ~T0-0.5 s and has a total duration of ~10 s.
The emission is seen up to ~10 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB200125_T74611/

As observed by Konus-Wind, the burst
had a fluence of 6.01(-0.36,+0.37)x10^-5 erg/cm2,
and a 64-ms peak flux, measured from T0+1.312 s,
of 3.92(-0.44,+0.46)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum of the burst
(measured from T0 to T0+12.288 s)
is best fit in the 20 keV - 10 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.91(-0.06,+0.07),
the high energy photon index beta = -2.48(-0.15,+0.12),
the peak energy Ep = 211(-15,+16) keV
(chi2 = 98/97 dof).

The spectrum near the maximum count rate
(measured from T0+1.280 to T0+1.536 s)
is best fit in the 20 keV - 4 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.43(-0.14,+0.16),
the high energy photon index beta = -2.64(-0.34,+0.21),
the peak energy Ep = 295(-36,+39) keV
(chi2 = 63/51 dof).

All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.


GRB_name: GRB200131A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26953
SUBJECT: GRB 200131A: Swift detection of a burst with an optical counterpart
DATE:    20/01/31 22:53:30 GMT
FROM:    Jamie A. Kennea at PSU/Swift-XRT  <kennea@swift.psu.edu>

B. Sbarufatti (PSU), D. N. Burrows (PSU), J.D. Gropp (PSU),
J. A. Kennea (PSU), N. J. Klingler (PSU), S. Laha (GSFC/UMBC/CRESST),
A. Y. Lien (GSFC/UMBC), F. E. Marshall (NASA/GSFC), M. H. Siegel (PSU)
and A. Tohuvavohu (U Toronto) report on behalf of the Neil Gehrels
Swift Observatory Team:

At 22:41:15 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 200131A (trigger=953689).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 3.095, +51.124 which is 
   RA(J2000) = 00h 12m 23s
   Dec(J2000) = +51d 07' 25"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a multi-peaked
structure with a duration of about 5 sec. There might be a small
pulse at T+30 s. The peak count rate was ~60000 counts/sec 
(15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 22:42:24.7 UT, 68.7 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 3.0942, 51.1158 which is equivalent to:
   RA(J2000)  = 00h 12m 22.61s
   Dec(J2000) = +51d 06' 56.9"
with an uncertainty of 4.9 arcseconds (radius, 90% containment). This
location is 29 arcseconds from the BAT onboard position, within the BAT
error circle. No event data are yet available to determine the column
density using X-ray spectroscopy. 

The initial flux in the 2.5 s image was 3.76e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 77 seconds after the BAT trigger. There is a candidate afterglow in
the rapidly available 2.7'x2.7' sub-image at
  RA(J2000)  = 00:12:22.57 = 3.09403
  DEC(J2000) = +51:07:00.4  =  51.11678
with a 90%-confidence error radius of about 0.61 arc sec. This position is 3.6
arc sec. from the center of the XRT error circle. The estimated magnitude is
15.44 with a 1-sigma error of about  0.14. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.17. 

Burst Advocate for this burst is B. Sbarufatti (bxs60 AT psu.edu). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB200131A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26954
SUBJECT: GRB 200131A: MASTER optical transient detection
DATE:    20/01/31 23:13:16 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov, N.Tyurina, E. Gorbovskoy, O.Gress, V.Kornilov, P.Balanutsa,A.Kuznetsov,
V. Vladimirov, D. Vlasenko, F.Balakin, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva,
D. Kuvshinov, V.Shumkov (Lomonosov Moscow State University, SAI, Physics Department),
D. Buckley(South African Astronomical Observatory),
R. Rebolo, M. Serra(The Instituto de Astrofisica de Canarias),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
R. Podesta, C.Lopez, F. Podesta, C.Francile(Observatorio Astronomico Felix Aguilar OAFA),
H. Levato(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE),
O.A. Gres, N.M. Budnev, O.Ershova (Irkutsk State University, API),
V. Yurkov, A. Gabovich, Yu. Sergienko(Blagoveschensk Educational State University)

MASTER Global Robotic Net (http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy,v. 2010, 30L)
started Swift GRB 200131A (Sbarufatti et al. GCN 26953) alert observation 
50s after trigger time (Lipunov et al. GCN 26952) at MASTER-Tunka and 78s 
after trigger time at MASTER-IAC.

MASTER auto-detection system found 
MASTER OT J001222.56+510700.3 at 
RA,Dec(2000) = 00h 12m 22.56s , +51d 07m 00s.3
with m_OT=14.5 (unfiltered) at the first exposition (10s)
with optical decay ,
also detected by Swift UVOT (GCN 26953)

Observation and reduction will be continued


GRB_name: GRB200201A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26955
SUBJECT: GRB 200201A: Fermi GBM Final Real-time Localization
DATE:    20/02/01 01:07:36 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 00:57:20 UT on 1 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200201A (trigger 602211445.321872 / 200201040).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 287.7, Dec = -11.0 (J2000 degrees, equivalent to J2000 19h 10m, -11d 00'), with a statistical uncertainty of 6.7 degrees.

The angle from the Fermi LAT boresight is 54.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200201040/quicklook/glg_skymap_all_bn200201040.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200201040/quicklook/glg_healpix_all_bn200201040.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200201040/quicklook/glg_lc_medres34_bn200201040.gif


GRB_name: GRB200131A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26956
SUBJECT: GRB 200131A: Enhanced Swift-XRT position
DATE:    20/02/01 03:59:52 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 2283 s of XRT Photon Counting mode data and 6 UVOT
images for GRB 200131A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 3.09439, +51.11676 which is equivalent
to:

RA (J2000): 00h 12m 22.65s
Dec (J2000): +51d 07' 00.4"

with an uncertainty of 1.5 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB200131A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26957
SUBJECT: GRB 200131A: RATIR Optical Observations
DATE:    20/02/01 04:26:12 GMT
FROM:    Nat Butler at UC berkeley  <natxbutler@gmail.com>

Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William
H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J. Xavier
Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI), Eleonora
Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), JesÃºs
GonzÃ¡lez (UNAM), Carlos RomÃ¡n-ZÃºÃ±iga (UNAM), Harvey Moseley (GSFC), John
Capone (UMD), V. Zach Golkhou (U. Wash.), and Vicki Toy (UMD) report:

We observed the field of GRB 200131A (Sbarufatti et al., GCN 26953) with
the Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on
the 1.5m Harold Johnson Telescope at the Observatorio AstronÃ³mico Nacional
on Sierra San Pedro MÃ¡rtir from 2020/02 1.10 to 2020/02 1.14 UTC (3.79 to
4.61 hours after the BAT trigger), obtaining a total of 0.64 hours exposure
in the r and i bands.

The optical transient (see, also, Lipunov et al., GCN  26954) is
well-detected.  We find:

  r = 19.97 +/- 0.04
  i = 19.75 +/- 0.02

These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.

We thank the staff of the Observatorio AstronÃ³mico Nacional in San Pedro
MÃ¡rtir.


GRB_name: GRB200131A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26958
SUBJECT: GRB 200131A: KAIT Optical Upper Limit
DATE:    20/02/01 04:34:37 GMT
FROM:    Weikang Zheng at UC Berkeley  <weikang@berkeley.edu>

WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on
behalf of the KAIT GRB team:

The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at
Lick Observatory, responded to Swift GRB 200131A (Sbarufatti et al.,
GCN 26953) starting at 4.15 hours after the burst. Observations
were performed in the clear (roughly R) filters, a total of 11
images were obtained and the exposure time was 60 s per image.
We do not detect the optical afterglow reported by UVOT (Sbarufatti
et al., GCN 26953; see also Lipunov et al. GCN 26954; Butler
et al. GCN 26957), neither in single image nor in the co-add image.
The limiting magnitude estimated from our coadd image is about 19.5 mag.


GRB_name: GRB200131A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26959
SUBJECT: GRB 200131A: LCO Optical Detection
DATE:    20/02/01 05:13:29 GMT
FROM:    Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh@uvi.edu>

R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (U. of the Virgin Islands/College of Marin) report on behalf of a larger collaboration:

We observed Swift GRB 200131A (Kennea et al., GCN 26953) with the LCO 1-m Sinistro instrument at the McDonald Observatory, Texas, USA site on January 31, from 01:59 to 02:22 UT (corresponding to 3.1 to 3.6 hours after the GRB trigger time) with the Bessel R and I filters.

We performed a series of 5x120s exposures in each band. We detect a source in the Swift-BAT refined error region (Evans et al., GCN 26956) that is not present in either USNO-B1.0 or 2MASS  surveys with the following  magnitudes:

R = 19.75 +/- 0.13

I = 19.31 +/- 0.14

This flux measurement is calibrated against several USNO-B1.0 objects near the GRB location and is not corrected for Galactic Extinction.


GRB_name: GRB200131A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26960
SUBJECT: GRB 200131A: VIRT optical transient detection
DATE:    20/02/01 05:23:11 GMT
FROM:    Priyadarshini Gokuldass at U. of the Virgin Islands  <priyadass.94@gmail.com>

P. Gokuldass (UVI), D. Morris (UVI), N. Orange (OrangeWave Innovative
Science, LLC), A. Cucchiara (College of Marin), R. Strausbaugh (UVI) report:


We observed the field of GRB 200131A (Sbarufatti et al. GCN 26953) with the
0.5m Virgin Island Robotic Telescope (VIRT) at the University of the Virgin
Islands' Etelman Observatory on 01-31-2020 starting at 23:28:45 UT (T+67
minutes). We performed a series of exposures in R filter. The weather
conditions were variable during the hours of observation and the zenith
angle at the start of observations was 54 degrees and setting. The midpoint
of the exposures is ~T+1.6 hrs. We observed the Swift XRT position with a
20'x20' field of view

We detect an uncatalogued source consistent with the UVOT position
(Sbarufatti et al. GCN 26953) and MASTER OT position (Lipunov et al. 26954)
with magnitude:

  R= 16.8 +/- 0.2

The magnitude is estimated from comparison to nearby USNO B1 stars and is
not corrected for Galactic extinction. The VIRT is still in the
commissioning phase.

This work is supported by NASA-MUREP-MIRO grant NNX15AP95A, NSF EiR AST
Award 1901296, and NSF HBCU-UP AST Award 1831682. This message can be cited.


GRB_name: GRB200131A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26961
SUBJECT: GRB 200131A: Swift-XRT refined Analysis
DATE:    20/02/01 08:55:16 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), J.P. Osborne
(U. Leicester), M.G. Bernardini (INAF-OAB), E. Ambrosi (INAF-IASFPA) ,
M. Capalbi (INAF-IASFPA), D.N. Burrows (PSU), J. D. Gropp (PSU) and B.
Sbarufatti report on behalf of the Swift-XRT team:

We have analysed 6.1 ks of XRT data for GRB 200131A (Sbarufatti et al.
GCN Circ. 26953), from 61 s to 17.4 ks after the  BAT trigger. The data
comprise 249 s in Windowed Timing (WT) mode (the first 5 s were taken
while Swift was slewing) with the remainder in Photon Counting (PC)
mode. The enhanced XRT position for this burst was given by Goad et al.
(GCN Circ. 26956). We cannot determine at the present time whether the
source is fading.

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.83 (+0.04, -0.03). The
best-fitting absorption column is  consistent with the Galactic value
of 1.8 x 10^21 cm^-2 (Willingale et al. 2013). The PC mode spectrum has
a photon index of 1.81 (+0.15, -0.14) and a best-fitting absorption
column of 2.3 (+0.6, -0.4) x 10^21 cm^-2. The counts to observed
(unabsorbed) 0.3-10 keV flux conversion factor deduced from this
spectrum  is 4.0 x 10^-11 (5.2 x 10^-11) erg cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      2.3 (+0.6, -0.4) x 10^21 cm^-2
Galactic foreground: 1.8 x 10^21 cm^-2
Excess significance: <1.6 sigma
Photon index:      1.81 (+0.15, -0.14)

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00953689.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB200131A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26962
SUBJECT: GRB 200131A: Swift/UVOT Detection
DATE:    20/02/01 14:37:48 GMT
FROM:    Paul Kuin at MSSL  <npkuin@gmail.com>

N. P. M. Kuin (UCL-MSSL) and B. Sbarufatti (PSU)report on behalf of
the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 200131A
78 s after the BAT trigger (Sbarufatti et al., GCN Circ. 26953).
A source consistent with the XRT position (Goad et al. GCN Circ. 26956)
is detected in the initial UVOT exposures.

The preliminary UVOT position is:
    RA  (J2000) =  00:12:22.57 =   3.09405 (deg.)
    Dec (J2000) = +51:07:00.3  =  51.11675 (deg.)
with an estimated uncertainty of 0.42 arc sec. (radius, 90% confidence).

The source has been detected also by MASTER (Lipunov et al. GCN Circ. No.
26954), RATIR (Butler et al., GCN Circ. No. 26957), MacDonalds Observatory
(Strausbaugh et al., GCN Circ. No. 26959),  and VIRT (Gokuldass et al.,
GCN Circ. No. 26960.

Preliminary detections using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures
are:

Filter         T_start(s)   T_stop(s)      Exp(s)           Mag

white               78          227          147         15.47 +/- 0.02
v                 4281         5919          393         19.57 +/- 0.28
b                 5103         5303          197         19.53 +/- 0.16
u                  290          323           32         16.09 +/- 0.08
w1                4692         4892          197         18.48 +/- 0.18
m2                4486         6124          393         18.98 +/- 0.20
w2                4076         5714          393         19.06 +/- 0.19

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.17 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB200131A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26964
SUBJECT: GRB 200131A: CDK700 optical observations
DATE:    20/02/02 21:01:36 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

A. Pozanenko (IKI), V. Kim (AFIF, Pulkovo Observatory),  I. Reva (AFIF), 
M. Krugov (AFIF), E. Mazaeva  (IKI), A. Volnova (IKI) report on behalf 
of larger GRB IKI FuN collaboration:

We observed the field of the  GRB 200131A   (Sbarufatti al., GCN  26953) 
with CDK700 (0.7m) telescope  of Assy-Turgen observatory starting on 
Feb. 01  (UT) 14:58:49  in  R-filter.    We marginally detect the 
optical afterglow (Sbarufatti al., GCN  26953; Lipunov  al., GCN  26954; 
Butler al., GCN  26957; Strausbaugh al., GCN  26959; Kuin al., GCN  26962).

Preliminary photometry of the afterglow is following.

Date       UT start   t-T0       Filter Exp.   OT   Err.  UL(3sigma)
                       (mid, days)        (s)

2019-02-01 14:58:49   0.76733     R    14*360  21.4 0.3   21.5

The photometry is based on nearby USNO-B1.0  stars  (R2 magnitudes).


GRB_name: GRB200131A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26965
SUBJECT: GRB 200131A: ISON-Castelgrande optical observations
DATE:    20/02/02 21:30:37 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

A. Pozanenko (IKI), S. Schmalz (KIAM),  V. Kim (AFIF, Pulkovo 
Observatory),  E. Mazaeva  (IKI), A. Volnova (IKI),  I. Molotov (KIAM) 
report on behalf of larger GRB follow-up collaboration:

We observed the field of the  GRB 200131A   (Sbarufatti al., GCN  26953) 
  with  ORI-22 telescope of ISON-Castelgrande observatory starting on 
Jan. 31  (UT) 23:11:28.  We obtained 120 images of 60 s exposure in 
Clear filter.  The optical afterglow  (Sbarufatti al., GCN  26953; 
Lipunov  al., GCN  26954; Butler al., GCN  26957; Strausbaugh al., GCN 
26959; Kuin al., GCN  26962)   is best detected in the stacked image of 
the first 60 images.
Preliminary photometry  of the  afterglow  is following

Date       UT start   t-T0       Filter Exp.   OT   Err.
                        (mid, days)        (s)

2019-01-31 23:11:28   0.04353     Clear 60*60  18.35 0.25

The photometry is based on nearby USNO-B1.0  stars  (R2 magnitude).


GRB_name: GRB200128A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26966
SUBJECT: ZTF Discovery of ZTF20aajnksq: a Rapidly Fading Luminous Transient in the GRB 200128A Localiziation Region
DATE:    20/02/02 21:53:10 GMT
FROM:    Anna Ho at Caltech  <annayqho@gmail.com>

The Zwicky Transient Facility (ZTF; ATel #11266) reports the discovery of
ZTF20aajnksq, a rapidly fading red transient located at
12:47:04.87 +45:12:02.3 (J2000)
191.770292 +45.200626 (J2000)
and detected as part of the ZTF Uniform Depth Survey (Goldstein et al. in
prep).

The source was discovered on UT 2020-01-28T06:43:20.640 at r=19.6 mag,
which was 0.74 days after the last non-detection. Follow-up photometry with
the IO:O optical imager on the Liverpool Telescope (PI: D. Perley) and the
Wafer-Scale Imager for Prime (WASP) on the 200-inch Hale telescope (PI: I.
Andreoni) at Palomar Observatory established a rapid fade rate of 2.5
magnitudes in 1.25 days as well as red colors (g-r=+0.65, from the WASP
observation).

We obtained a target-of-opportunity (PI: M. M. Kasliwal) spectrum with the
Low Resolution Imaging Spectrometer (LRIS) on the Keck I 10-m telescope,
which showed features consistent with the Lyman break and Lyman alpha
absorption at z=2.9.

We obtained a target-of-opportunity observation with the Neil Gehrels Swift
Observatory (Swift) and detected X-ray emission at 0.0039 ct/s. Assuming a
neutral hydrogen column density n_H = 1.77E20/cm2 and a power-law spectrum
with photon index 2, the unabsorbed flux is 1.5E-13 erg/cm^2/s,
corresponding to a luminosity of 1.1E46 erg/s.

We searched the Fermi/GBM catalog and identified a reported likely short
GRB 24 degrees away: GRB 200128A (GCN #26909). ZTF20aajnksq is located
along the 90% contour of the localization region. The trigger time of GRB
200128A is three hours before the first optical detection.

We are grateful to the staff of Palomar and Keck for rapidly scheduling our
observations, and to M. Heida (ESO Garching) and J. Rhoads (Goddard) for
accommodating the interruption to their scheduled programs. Thank you to
the Swift team for rapidly scheduling and executing our observations.

ZTF is a project led by PI S. R. Kulkarni at Caltech (see ATEL #11266), and
includes IPAC; WIS, Israel; OKC, Sweden; JSI/UMd, USA; UW,USA; DESY,
Germany; NRC, Taiwan; UW Milwaukee, USA and LANL USA. ZTF acknowledges the
generous support of the NSF under AST MSIP Grant No 1440341. Alert
distribution service provided by DIRAC@UW. Alert filtering is being
undertaken by the GROWTH marshal system, supported by NSF PIRE grant
1545949.


GRB_name: GRB200131A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26967
SUBJECT: GRB 200131A: Swift-BAT refined analysis
DATE:    20/02/03 00:35:33 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

T. Sakamoto (AGU), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), H. A. Krimm (NSF),
S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), J. P. Norris (BSU),
D. M. Palmer (LANL), B. Sbarufatti (PSU),
 M. Stamatikos (OSU), T. N. Ukwatta (LANL)
(i.e. the Swift-BAT team):

Using the data set from T-200 to T+963 sec from the recent telemetry
downlink,
we report further analysis of BAT GRB 200131A (trigger #953689)
(Sbarufatti et al., GCN Circ. 26953).  The BAT ground-calculated position is
RA, Dec = 3.067, 51.121 deg which is
   RA(J2000)  =  00h 12m 16.2s
   Dec(J2000) = +51d 07' 15.6"
with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 96%.

The mask-weighted light curve shows several bright overlapping
pulses that starts from ~T-3.5 s and ends at ~T+3. It is followed by
another weaker pulse at ~T+30 s and some weak emission that lasts
till ~T+60 s. The burst went out of the BAT FOV at T+472 s.
T90 (15-350 keV) is 32.74 +- 0.88 sec (estimated error including
systematics).

The time-averaged spectrum from T-3.45 to T+46.56 sec is best fit by a
simple
power-law model.  The power law index of the time-averaged spectrum is
1.32 +- 0.04.  The fluence in the 15-150 keV band is 7.0 +- 0.1 x 10^-6
erg/cm2.
The 1-sec peak photon flux measured from T+0.02 sec in the 15-150 keV band
is 26.9 +- 0.6 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The spectral lag of the initial bright structure from ~T-2.5 s to ~T+3 s
is 49 (+3, -3) ms for the 100-350 keV to 25-50 keV bands, and 43 (+5, -7) ms
for the 50-100 keV to 15-25 keV bands. These values are consistent with
this of long GRBs.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/953689/BA/


GRB_name: GRB200128A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26968
SUBJECT: ZTF20aajnksq: Gemini-North r-band photometry
DATE:    20/02/03 02:54:07 GMT
FROM:    Leo Singer at GSFC  <leo.p.singer@nasa.gov>

ZTF20aajnksq: Gemini-North optical photometry

Leo P. Singer (NASA/GSFC), Tomas Ahumada (UMD), Anna Y. Q. Ho (Caltech)
report on behalf of the Zwicky Transient Facility (ZTF) and Global Relay
of Observatories Watching Transients Happen (GROWTH) collaborations:

Starting at 2020-02-01T12:25:57 UTC, we imaged ZTF20aajnksq/AT2020blt
(Ho et al., ATel #13429, GCN 26966) using the Gemini Multi-Object
Spectrograph (GMOS) mounted on the Gemini North 8-meter telescope on
Mauna Kea.

We combined 8 r-band 200s exposures using DRAGONS, a Python-based data
reduction platform provided by the Gemini Observatory. We detect a source
at the location of the transient. The aperture photometry calibrated
against Pan-STARRS DR1 magnitudes (Chambers et al., 2016) of the object is
r = 25.2 +- 0.05 AB mag.

We note that for the redshift (z = 2.9) and apparent magnitude
(r = 19.6 AB mag) reported in GCN 26966, the absolute magnitude of the
source (M_r = -27.4) would be significantly brighter than afterglows of
short GRBs at one day: short GRBs are typically M_B = -17.34 +- 0.50 AB
mag whereas long GRBs are typically M_B = -23.17 +- 0.21 AB mag (Kann et
al., 2011). We therefore suggest three alternative interpretations:
(a) GRB 200128A is not a typical short GRB, (b) ZTF20aajnksq is the
afterglow of a different (long) GRB, or (c) ZTF20aajnksq is an orphan
afterglow.

We thank S. Stewart and the Gemini North staff for executing these
observations.


GRB_name: GRB200128A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26970
SUBJECT: ZTF20aajnksq: Occulted by Earth at the time of GRB 200128A
DATE:    20/02/03 04:40:02 GMT
FROM:    Rachel Hamburg at UAH  <rkh0007@uah.edu>

R. Hamburg (UAH) reports on behalf of the Fermi-GBM Team:

The newly discovered transient ZTF20aajnksq (GCN 26966)
was found within the 3-sigma localization contour of
GRB 200128A (GCN 26909) approximately 3 hours after the
GBM trigger time. However the reported position
of ZTF20aajnksq:

12:47:04.87 +45:12:02.3 (J2000)
191.770292 +45.200626 (J2000)

was occulted by the Earth for Fermi-GBM from approximately
25.3 minutes prior until 1.8 minutes after the GRB trigger
time. The position was also occulted 18.0 minutes prior
until 8.8 minutes after the ZTF20aajnksq detection time.
Therefore, we consider it unlikely that GRB 200128A is
associated with ZTF20aajnksq.


GRB_name: GRB200131A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26972
SUBJECT: GRB 200131A: CALET Gamma-Ray Burst Monitor detection
DATE:    20/02/03 07:07:14 GMT
FROM:    Valentin Pal'shin at AGU  <val@phys.aoyama.ac.jp>

S. Ricciarini (U of Florence),
A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
Y. Asaoka, S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U),
N. Cannady (GSFC/UMBC), M. L. Cherry (LSU),
P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

The bright GRB 200131A detected by Swift (Sbarufatti et al.,
GCN Circ. 26953, Sakamoto et al., GCN Circ. 26967;
https://gcn.gsfc.nasa.gov/other/200131A.gcn3)
triggered the CALET Gamma-ray Burst Monitor (CGBM) at 22:41:11.299 UTC
on 31 January 2020. The burst signal was seen by all CGBM detectors.

The burst light curve shows a multi-peaked structure which starts
at T+3.3 sec, peaks at T+3.8 sec and ends at T+6.4 sec.
The T90 and T50 durations measured by the SGM data are 2.2 +- 0.1 sec
and 1.4 +- 0.1 sec (40-1000 keV), respectively.

The ground processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1264545439/

The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at the Waseda University.


GRB_name: GRB200120A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26974
SUBJECT: GRB200120A: SRG/ART-XC Upper Limit
DATE:    20/02/03 16:06:32 GMT
FROM:    Sergey Molkov at Space Research Inst., Moscow  <molkov@iki.rssi.ru>

S.Molkov, A.Lutovinov, M.Pavlinsky, I.Lapshov,
A.Tkachenko and A.Semena (IKI RAN)
report on behalf of SRG/ART-XC team:

The SRG/ART-XC telescope crossed the GBM localization region of
GRB200120A (GCN26831) and its IPN triangulation (GCN26856)
several times after the event. The first pass was approximately
800 seconds after the event time and covered the sky region between
lines defined by two pairs of the RA, DEC (J2000) coordinates:
1st (142.420, -69.397) , (130.997, -70.584);
2nd (147.762, -69.996) , (130.734, -71.192).
This region has approximately 60% cross section area with the IPN
triangulation. We do not detect with ART-XC any source around
the GRB200120A position with the upper limit, averaged over FoV,
of ~2e-11 ergs/s/cm2 in the 4-12 keV energy band neither in this
pass nor in subsequent ones  followed every 4 hours during next
few days.

The history of observations is available at
http://hea.iki.rssi.ru/molkov/GRB200120A/


GRB_name: GRB200131A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26975
SUBJECT: Konus-Wind observation of GRB 200131A
DATE:    20/02/03 16:09:21 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks,
M. Ulanov, A. Tsvetkova, A. Lysenko, A. Ridnaia, and T. Cline
on behalf of the Konus-Wind team, report:

The long-duration, bright GRB 200131A
(Swift-BAT detection: Sbarufatti et al., GCN Circ. 26953;
Sakamoto et al., GCN Circ. 26967;
CALET Gamma-Ray Burst Monitor detection: Ricciarini et al., GCN 26972)
triggered Konus-Wind at T0=81673.507 s UT (22:41:13.507).

The burst light curve shows a bright, multi-peaked structure
which starts at ~T0-0.1 s and has a duration of ~3 s,
followed by a weaker episode at ~T0+32 s.
The emission is seen up to ~4 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB200131_T81673/

As observed by Konus-Wind, the burst
had a fluence of 1.60(-0.08,+0.09)x10^-5 erg/cm2,
and a 64-ms peak flux, measured from T0+0.068 s,
of 1.64(-0.27,+0.28)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The spectrum of the brightest episode
(measured from T0 to T0+9.984 s)
is best fit in the 20 keV - 4 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with  alpha = -0.80(-0.09,+0.10)
and Ep = 228(-15,+17) keV (chi2 = 43/72 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -3.2
(chi2 = 43/71 dof).

The spectrum near the maximum count rate
(measured from T0 to T0+0.256 s)
is best fit in the 20 keV - 4 MeV range
by a power law with exponential cutoff model:
with alpha = 0.01(-0.19,+0.21)
and Ep = 266(-22,+25) keV (chi2 = 49/38 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2.8
(chi2 = 46/37 dof).

All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.


GRB_name: GRB200205A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26982
SUBJECT: GRB 200205A: Swift detection of a burst with a possible UV counterpart
DATE:    20/02/05 07:14:19 GMT
FROM:    Kim Page at U.of Leicester  <klp5@leicester.ac.uk>

P. A. Evans (U Leicester), A. Y. Lien (GSFC/UMBC),
K. L. Page (U Leicester), K. K. Simpson (PSU) and
A. Tohuvavohu (U Toronto) report on behalf of the Neil Gehrels Swift
Observatory Team:

At 06:35:51 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 200205A (trigger=954304).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 130.171, -35.245 which is 
   RA(J2000) = 08h 40m 41s
   Dec(J2000) = -35d 14' 39"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty). As is usual with an image trigger, the available
BAT light curve shows no significant structure. 

The XRT began observing the field at 06:38:07.9 UT, 136.3 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 130.1717, -35.2715 which is equivalent to:
   RA(J2000)  = 08h 40m 41.21s
   Dec(J2000) = -35d 16' 17.4"
with an uncertainty of 5.0 arcseconds (radius, 90% containment). This
location is 95 arcseconds from the BAT onboard position, within the BAT
error circle. No event data are yet available to determine the column
density using X-ray spectroscopy. 

The initial flux in the 2.5 s image was 3.00e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 250 seconds with the UVW2 filter
starting  139 seconds after the BAT trigger. There is a possible UVOT
counterpart close to the XRT position, but we cannot provide precise
coordinates at this time. 

Burst Advocate for this burst is P. A. Evans (pae9 AT star.le.ac.uk). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB200205A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26983
SUBJECT: Swift GRB 200205A: Global MASTER-Net observations report 
DATE:    20/02/05 07:36:11 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, 
V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva,
D.Kuvshinov,  D. Cheryasov
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile 
(Observatorio Astronomico Felix Aguilar OAFA),

H.Levato 
(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE),

R. Rebolo, M. Serra 
(The Instituto de Astrofisica de Canarias),

D. Buckley 
(South African Astronomical Observatory),

O.A. Gres, N.M. Budnev, O.Ershova 
(Irkutsk State University, API),

A. Tlatov, D. Dormidontov 
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich, Yu. Sergienko 
(Blagoveschensk Educational State University)




MASTER-OAFA robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Argentina (OAFA observatory of San Juan National University) was pointed to the Swift GRB 200205A ( P. A. Evans et al., GCN 26982) errorbox  24 sec after notice time and 916 sec after trigger time at 2020-02-05 06:51:08 UT, with upper limit up to  18.9 mag. The observations began at zenith distance = 32 deg. The sun  altitude  is -34.4 deg. 

The galactic latitude b =  4 deg., longitude l = 257 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1278043

We obtain a following upper limits.  

Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________

    1007 |         MASTER-OAFA |   C |   180 | 18.9 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.


GRB_name: GRB200205A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26984
SUBJECT: GRB 200205A: MASTER Ot detection
DATE:    20/02/05 08:17:29 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov, E. Gorbovskoy, N.Tiurina, V.Kornilov, P.Balanutsa,A.Kuznetsov,
V. Vladimirov, O.Gress, D. Vlasenko, F.Balakin, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva,
D. Kuvshinov, V.Shumkov (Lomonosov Moscow State University, SAI, Physics Department),
D. Buckley(South African Astronomical Observatory),
R. Rebolo, M. Serra(The Instituto de Astrofisica de Canarias),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
R. Podesta, C.Lopez, F. Podesta, C.Francile(Observatorio Astronomico Felix Aguilar OAFA),
H. Levato(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE),
O.A. Gres, N.M. Budnev, O.Ershova (Irkutsk State University, API),
V. Yurkov, A. Gabovich, Yu. Sergienko(Blagoveschensk Educational State University)

MASTER Global Robotic Net (http://observ.pereplet.ru, Lipunov et al., 2010,Advances in Astronomy,v. 2010, 30L)
observed Swift GRB 200205A (Evans et al. GCN 26982, Lipunov et al GCN 26983)
MASTEr auto-detection system detected new variable OT

MASTER OT J084040.87-351625.3
at RA,Dec2000= 08 40 40.87 -35 16 25.3
with m_OT=15.8

observation and reduction will be continued


GRB_name: GRB200205A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26986
SUBJECT: GRB 200205A: REM optical observations
DATE:    20/02/05 09:32:24 GMT
FROM:    Andrea Melandri at INAF-OAB  <andrea.melandri@inaf.it>

A. Melandri, S.Covino, D. Fugazza, P. D'Avanzo (INAF/OAB), on behalf of the REM team, report:


We observed the field of GRB200205A (Evans et al. GCN 26982) with the REM 60cm robotic telescope located at the ESO premise of La Silla (Chile). The observations were performed starting from about 6 min after the event and were carried in the g, r, i, z bands. 

The optical counterpart (Lipunov et al. GCN 2698) is detected in all the optical bands. A preliminary photometry gives:

R = 16.3 +/- 0.1
I = 16.8 +/- 0.1

at 19 min from the GRB time. Magnitudes are calibrated against the USNO-B1 catalogue.


GRB_name: GRB200205A
Detection_method: MAXI Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26987
SUBJECT: GRB 200205A: MAXI/GSC detection
DATE:    20/02/05 11:00:12 GMT
FROM:    Motoko Serino at RIKEN/MAXI  <motoko@crab.riken.jp>

M. Niwano (Tokyo Tech), T. Mihara (RIKEN), M. Nakajima (Nihon U.), M. Serino (AGU),
H. Negoro, W. Maruyama, M. Aoki, K. Kobayashi, R. Takagi (Nihon U.),
C. Guo, Y. Zhou, T. Tamagawa, M. Matsuoka (RIKEN),
T. Sakamoto, S. Sugita, H. Nishida, A. Yoshida (AGU),
Y. Tsuboi, W. Iwakiri, R. Sasaki, H. Kawai, T. Sato (Chuo U.),
M. Shidatsu (Ehime U.),
N. Kawai, M. Oeda, K. Shiraishi (Tokyo Tech),
S. Nakahira, Y. Sugawara, S. Ueno, H. Tomida, M. Ishikawa, R. Shimomukai, M. Tominaga (JAXA),
Y. Ueda, A. Tanimoto, S. Yamada, S. Ogawa, K. Setoguchi, T. Yoshitake (Kyoto U.),
H. Tsunemi, T. Yoneyama, K. Asakura, S. Ide (Osaka U.),
M. Yamauchi, S. Iwahori, Y. Kurihara, K. Kurogi, K. Miike (Miyazaki U.),
T. Kawamuro (NAOJ),
K. Yamaoka (Nagoya U.),
Y. Kawakubo (LSU),
M. Sugizaki (NAOC) 
report on behalf of the MAXI team:

The MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient source at UT 2020-02-05T06:54.
Assuming that the source flux was constant over the transit,
we obtain the source position at
(R.A., Dec) = (130.230 deg, -35.413 deg) = (08 40 55, -35 24 46) (J2000)
with a 90% C.L. statistical error of 0.17 deg and an additional systematic uncertainty of 0.1 deg (90% containment radius).
This position is consistent with that of GRB 200205A triggered by Swift (GCN#26982) on 2020-02-05T06:35.
The X-ray flux in 4.0-10.0 keV energy band rapidly incrased, 72 mCrab (2020-02-05T06:54) to 262 mCrab (2020-02-05T07:16).  
In the next transit at 2020-02-05T08:27, the source was detected only in the 2.0-4.0 keV energy band with the flux of 66 +- 18 mCrab. 
There was no significant excess flux in the previous transit at UT 05:43
and in the next transit at 08:49 UT with an upper limit of 20 mCrab for each.


GRB_name: GRB200120A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26988
SUBJECT: GRB200120A: SRG/eROSITA discovery of X-ray afterglow
DATE:    20/02/05 15:50:25 GMT
FROM:    Arne Rau at MPE  <arau@mpe.mpg.de>

P. Weber (FAU), A. Rau (MPE), Th. Dauser (FAU), I. Kreykenbohm (FAU), J. 
Wilms (FAU) report:

The location of the Fermi/GBM long duration GRB 200120A (#26831, #26840, 
#26851, #26856, #26857, #26974) was observed by SRG/eROSITA as part of 
its all-sky survey between UTC 2020 Jan 16th and Jan 24th.  Throughout 
this period, the instrument scanned over the position with a cadence of 4hr.

On UTC Jan 20th 23:18:15 (820 seconds after the Fermi/GBM trigger) we 
detected a bright and quickly fading X-ray source localized to

RA(J2000) =   09:08:32.1 (137.13364 deg)
Dec(J2000) = -70:25:11   (-70.43628 deg)

with an uncertainty of ~4" arcsec radius. This position is consistent 
with the Fermi/GBM (#26831) and IPN (#26856) localizations, suggesting 
the source to be the X-ray afterglow of GRB200120A.

At the time of discovery, the source was detected with a count rate of 
44+/-2 cnt/s in the 0.2-10keV band, corresponding to a flux of approx. 
1x10E-10 erg/cm^2/s. The source was also found during the next scan 4hr 
later. By then, it had faded to 2.8+/-0.5 cnt/s (approx. 6x10E-12 
erg/cm^2/s). Further detections were obtained in the following three 
scans with count rates of ~1+/-0.3 cnt/s. Nothing was seen in the scans 
prior to the Fermi/GBM detection.


GRB_name: GRB200205A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26989
SUBJECT: GRB 200205A / Swift trigger 954304: VLT optical observations
DATE:    20/02/05 18:32:10 GMT
FROM:    Daniele B Malesani at DTU Space  <malesani@space.dtu.dk>

D. B. Malesani (DTU Space), L. Izzo (DARK/NBI), J. Palmerio (GEPI - 
Paris Observatory), N. R. Tanvir (Univ. Leicester), A. J. Levan (Radboud 
Univ.), D. A. Kann (HETH-IAA/CSIC), report on behalf of the Stargate 
consortium:

We observed the optical counterpart of GRB 200205A / Swift trigger 
954304 (Evans et al., GCN 26982), with the ESO VLT UT2 (Kueyen) equipped 
with the X-shooter instrument. Unfortunately, observations could be 
started only late in twilight and no spectroscopy was secured.

We confirm the presence of an optical counterpart just outside the 
currently available (unenhanced) XRT position (Evans et al., GCN 26982; 
Lipunov et al., GCN 26984; Melandri et al., GCN 26986). Its coordinates 
are (calibrated to the Gaia catalog; 0.2" uncertainty):

RA = 08:40:40.94
Dec = -35:16:25.1

In a 60-s image taken in the SDSS r filter at a mid time Feb 5.385 UT 
(2.63 hr after the BAT trigger), we measure for it r = 17.7+-0.1 AB, 
where the error is dominated by the scatter of the calibrators, chosen 
from the SkyMapper catalog (Wolf et al. 2018, PASA, 35, 010; 
https:doi.org/10.4225/41/593620ad5b574).

We note that the MAXI detection for a prolonged time at X-ray energies 
(Niwano et al., GCN 26987), the unusually large optical/gamma-ray 
brightness ratio, and the low Galactic latitude (4 deg above the plane) 
may indicate that this source is not a GRB but a Galactic transient. 
Further analysis of the high-energy data, or ground-based spectroscopic 
observations, will be necessary to distinguish among these options.

We acknowledge support from the ESO observing staff in Paranal, in 
particular Elyar Sedaghati, Eleonora Sani, and Ditte Slumstrup.


GRB_name: GRB191221B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26990
SUBJECT: MeerKAT observation of GRB 191221B
DATE:    20/02/05 19:25:22 GMT
FROM:    Itumeleng Monageng at UCT/SAOO  <itu@saoo.ac.za>

Dear GCN circular admin,

This email serves to submit details of the radio observation of GRB191221B with MeerKAT. Please see the detail of the GCN draft below.

I. Monageng (UCT/SAAO), M. Boettcher (NWU), D.A.H Buckley (SAAO), R. Britto (UFS), S. Razzaque (UJ), B. van Soelen (UFS)


We observed GRB 191221B with the MeerKAT radio telescope on 21            January 2020 from 20:26 to 21:26 UTC (~30 days after the trigger) at a position consistent with the X-ray position reported by Beardmore et al. (GCN 26540). We used J0408-6545 as the bandpass and flux calibrator, which was observed for 10 minutes at the start of the observation. The phase calibrator used was J1120-2508, which was observed for 2 minutes before and after the two ~20 minute scans on GRB 191221B (20:41:04.0 - 21:00:55.5 and 21:03:51.5 - 21:23:50.9 UTC). The observation was performed with 60 antennas and is centered at a frequency of 1.28 GHz with a bandwidth of 856 MHz over 4096 channels. The GRB afterglow was not detected, and we report a 3-sigma upper limit of 64 micro Jy at the position of GRB 191221B.

We thank the team at the South African Radio Astronomy Observatory (SARAO) for observing this DDT request.




Best regards,
Itu


-- 
-------------------------------------------
Dr. Itumeleng M. Monageng
South African Astronomical Observatory/University of Cape Town
Tel:  +27(0) 21 460 9359 (SAAO)
Tel:  +27(0) 21 650 7347 (UCT)
Cell: 076 885 5437


GRB_name: GRB200205B
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26993
SUBJECT: GRB 200205B: Swift detection of a burst with optical counterpart
DATE:    20/02/05 19:46:01 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

P. A. Evans (U Leicester), J.D. Gropp (PSU), J. A. Kennea (PSU),
N. J. Klingler (PSU), A. Y. Lien (GSFC/UMBC),
F. E. Marshall (NASA/GSFC), M. J. Moss (GWU), K. L. Page (U Leicester)
and A. Tohuvavohu (U Toronto) report on behalf of the Neil Gehrels
Swift Observatory Team:

At 19:21:43 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 200205B (trigger=954519 and 954520).  Swift slewed
to the burst after a short delay. 
The BAT on-board calculated location is 
RA, Dec 107.861, -56.506 which is 
   RA(J2000) = 07h 11m 27s
   Dec(J2000) = -56d 30' 21"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a peak about 20 
seconds long (trigger 954519) followed by a brighter more complex 
peak structure 350 s later (trigger 954520) with a peak countrate
of 3500 counts/s.  Due to the double trigger, the complete
BAT lightcurve is not immediately available. 

The XRT began observing the field at 19:27:26.3 UT, 342.7 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
uncatalogued X-ray source with an enhanced position: RA, Dec 107.7881,
-56.4875 which is equivalent to:
   RA(J2000)  = 07h 11m 09.14s
   Dec(J2000) = -56d 29' 15.0"
with an uncertainty of 2.8 arcseconds (radius, 90% containment). This
location is 37 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at https://www.swift.ac.uk/sper.  We
cannot determine whether the source is fading at the present time. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 1.04
x 10^21 cm^-2 (Willingale et al. 2013). 

The initial flux in the 2.5 s image was 1.26e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 351 seconds after the BAT trigger. There is a candidate afterglow in
the rapidly available 2.7'x2.7' sub-image at
  RA(J2000)  = 07:11:09.15 = 107.78811
  DEC(J2000) = -56:29:15.1  = -56.48753
with a 90%-confidence error radius of about 0.61 arc sec. This position is 0.8
arc sec. from the center of the XRT error circle. The estimated magnitude is
16.43 with a 1-sigma error of about  0.14. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.11. 

Burst Advocate for this burst is P. A. Evans (pae9 AT star.le.ac.uk). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB200205C
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26994
SUBJECT: GRB 200205C: Fermi GBM Final Real-time Localization
DATE:    20/02/05 20:27:41 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 20:17:23 UT on 5 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200205C (trigger 602626648.328424 / 200205845).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 223.2, Dec = -42.8 (J2000 degrees, equivalent to J2000 14h 52m, -42d 47'), with a statistical uncertainty of 9.8 degrees.

The angle from the Fermi LAT boresight is 32.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200205845/quicklook/glg_skymap_all_bn200205845.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200205845/quicklook/glg_healpix_all_bn200205845.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200205845/quicklook/glg_lc_medres34_bn200205845.gif


GRB_name: GRB200205B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26995
SUBJECT: GRB 200205B: LCO Optical Detection
DATE:    20/02/05 21:37:40 GMT
FROM:    Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh@uvi.edu>

R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (U. of the Virgin Islands/College of Marin) report on behalf of a larger collaboration:

We observed Swift GRB 200205B (Evans et al., GCN 26993) with the LCO 1-m Sinistro instrument at the South African Astronomical Observatory site on February 5, from 19:38 to 20:00 UT (corresponding to 0.28 to 0.82 hours after the GRB trigger time) with the Bessel R and I filters.

We performed a series of 5x120s exposures in each band. We detect a source that is consistent with the Swift-XRT position (Evans et al., GCN 26993) and other optical detections (Lipunov et al., GCN 26991) and not present in either USNO-B1.0 or 2MASS surveys with the following  magnitudes:

R = 18.56 +/- 0.04

I = 17.15 +/- 0.03

These magnitudes are calibrated against several USNO-B1.0 objects near the GRB location and is not corrected for Galactic Extinction.

R.S. is funded by NSF AST grant #1831682


GRB_name: GRB200205A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26996
SUBJECT: GRB 200205A: Enhanced Swift-XRT position
DATE:    20/02/05 21:59:52 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 2012 s of XRT Photon Counting mode data and 5 UVOT
images for GRB 200205A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 130.17006, -35.27366 which is equivalent
to:

RA (J2000): 08h 40m 40.81s
Dec (J2000): -35d 16' 25.2"

with an uncertainty of 1.9 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB200205B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26998
SUBJECT: GRB 200205B: VLT/X-shooter redshift
DATE:    20/02/06 03:17:38 GMT
FROM:    Daniele B Malesani at DTU Space  <malesani@space.dtu.dk>

J.-B. Vielfaure (GEPI - Paris Observatory), D. Xu (NAO/CAS), J. Palmerio 
(GEPI - Paris Observatory), D. B. Malesani (DTU Space), L. Izzo 
(DARK/NBI), D. A. Kann (HETH/IAA-CSIC), A. J. Levan (Radboud Univ.), G. 
Pugliese (Univ. Amsterdam), N. R. Tanvir (Univ. Leicester) report on 
behalf of the Stargate collabaration:

We observed the optical afterglow of GRB 200205B (Evans et al., GCN 
26993) using the ESO VLT UT2 (Kueyen) equipped with the X-shooter 
spectrograph. Our spectra cover the wavelength range 3000-25000 AA, and 
consist of 4 exposures by 600 s each. The observation mid time was 2020 
Feb 6.063 UT (6.16 hr after the GRB).

In a 30 s image taken with the acquisition camera on Feb 6.041 UT, we 
detect the optical afterglow, for which we measure a magnitude r = 20.34 
+- 0.03 AB (calibrated against nearby stars from the SkyMapper catalog; 
Wolf et al. 2018, PASA, 35, 010; https:doi.org/10.4225/41/593620ad5b574).

We clearly detect continuum over the wavelength range 3100-24000 AA. 
 From detection of multiple absorption features, which we interpret as 
due to C ii, Si iv, Si ii, C iv, Fe ii, Al ii, Mg ii, we infer a 
redshift z = 1.465.
Emission lines are also detected, which we interpret as due to the [O 
ii] and [O iii] doublets, Hbeta, and Halpha, all at the above quoted 
redshift.

We acknowledge excellent support from the ESO observing staff in 
Paranal, in particular J. Corral-Santana and J. Velasquez.


GRB_name: GRB200205B
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  26999
SUBJECT: GRB 200205B: Enhanced Swift-XRT position
DATE:    20/02/06 03:52:10 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 1822 s of XRT Photon Counting mode data and 5 UVOT
images for GRB 200205B, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 107.78760, -56.48741 which is equivalent
to:

RA (J2000): 07h 11m 9.03s
Dec (J2000): -56d 29' 14.7"

with an uncertainty of 1.6 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB200205A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27000
SUBJECT: GRB 200205A = Swift J0840.7-3516, A newly discovered transient X-ray Pulsar
DATE:    20/02/06 08:12:46 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J. A. Kennea (Penn State), D. M. Palmer (LANL), M. H. Siegel (Penn State), F. E.
Marshall (NASA/GSFC), P. A. Evans (U Leicester), A. Y. Lien (GSFC/UMBC), K. L.
Page (U Leicester), K. K. Simpson (Penn State), S. Campana (INAF-OAB) and A.
Tohuvavohu (U Toronto) report on behalf of the Neil Gehrels Swift Observatory
Team:

Swift trigger 954304 was initialy reported as GRB 200205A (Evans et al., GCN
Circ. 26982). The source was localized by XRT, and did not match any previously
known cataloged object. MAXI also reported a detection of this source (Niwano et
al., GCN Circ. 26987). The enhanced XRT position was reported by Osborne et al
(GCN Circ. 26996).

Examination of the downlnked Swift data shows that the source light-curve is not
behaving like a GRB, the flux over the three orbits of Windowed Timing XRT data
show no signs of overall fading, however the light-curve is highly variable,
showing both short and longer term variations. The mean flux over the first
three windows is 2.2 x 10^-9 erg/s/cm^2 (0.5 - 10 keV). However, in subsequent
observations starting ~3.3 hours after the trigger, the source fades
significantly, with PC mode flux measured at 3.7 x 10^-11 erg/s/cm^2 (0.5 - 10
keV).

A Z^2_1 period search of the WT event data reveals a possible detection of
coherent pulsations at P=8.96s, suggesting that this source is an accreting
pulsar, although longer periods (e.g. ~55s) cannot be ruled out due to aliasing
and the relatively short exposure this periodicity is based upon (754s). A
longer/more sensitive observation is needed in order to determine the
periodicity of this transient.

We note that the fitted spectrum of this source is hard, with a photon index of
1.06 +/- 0.05, which is typical of accreting pulsars.

Due to the presence of a bright star in the field, UVOT only took data in the UV
 filters. The preliminary UVOT position is: 

RA (J2000) = 08:40:40.96 = 130.17068 (deg.) 
Dec (J2000) = -35:16:25.0 = -35.27362 (deg.) 

with an estimated uncertainty of 0.47 arc sec. (radius, 90% confidence).

Preliminary detections using the UVOT photometric system (Breeveld et al. 2011,
 AIP Conf. Proc. 1358, 373) for the early exposures are:


Filter          T_start(s)   T_stop(s)      Exp(s)           Mag 
w2              139          389          246        17.09 +/- 0.09 
w2              4611         6293         661        16.69 +/- 0.07 

Follow-up observations are encouraged in order to determine the source type. 

This circular, a cross-posting of ATEL 13452, is an official product of the Swift team.


GRB_name: GRB200205B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27001
SUBJECT: GRB 200205B: Swift-XRT refined Analysis
DATE:    20/02/06 16:39:26 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J.P. Osborne (U. Leicester), M. Capalbi (INAF-IASFPA), M. Perri (ASDC),
V. D'Elia (ASDC), J. D. Gropp (PSU), J.A. Kennea (PSU), A. Tohuvavohu
(U. Toronto), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester)
and P.A. Evans report on behalf of the Swift-XRT team:

We have analysed 6.5 ks of XRT data for GRB 200205B (Evans et al. GCN
Circ. 26993), from 332 s to 46.4 ks after the  BAT trigger. The data
comprise 360 s in Windowed Timing (WT) mode (the first 8 s were taken
while Swift was slewing) with the remainder in Photon Counting (PC)
mode. The enhanced XRT position for this burst was given by Beardmore
et al. (GCN Circ. 26999).

The late-time light curve (from T0+5.3 ks) can be modelled with a
power-law decay with a decay index of alpha=0.76 (+0.14, -0.13).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.129 (+0.027, -0.026). The
best-fitting absorption column is  4.9 (+1.2, -1.1) x 10^21 cm^-2, at a
redshift of 1.465, in addition to the Galactic value of 1.0 x 10^21
cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index
of 1.93 (+0.19, -0.13) and a best-fitting absorption column of 1 (+35,
-1) x 10^20 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux
conversion factor deduced from this spectrum  is 3.5 x 10^-11 (4.2 x
10^-11) erg cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Galactic foreground: 1.0 x 10^21 cm^-2
Intrinsic column:    1 (+35, -1) x 10^20 cm^-2 at z=1.465
Photon index:      1.93 (+0.19, -0.13)

If the light curve continues to decay with a power-law decay index of
0.76, the count rate at T+24 hours will be 0.018 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 6.1 x
10^-13 (7.4 x 10^-13) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00954519.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB200206A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27002
SUBJECT: GRB 200206A: Fermi GBM Final Real-time Localization
DATE:    20/02/06 17:06:36 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 16:56:21 UT on 6 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200206A (trigger 602700986.456684 / 200206706).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 298.2, Dec = -49.1 (J2000 degrees, equivalent to J2000 19h 52m, -49d 06'), with a statistical uncertainty of 18.7 degrees.

The angle from the Fermi LAT boresight is 44.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200206706/quicklook/glg_skymap_all_bn200206706.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200206706/quicklook/glg_healpix_all_bn200206706.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200206706/quicklook/glg_lc_medres34_bn200206706.gif


GRB_name: GRB200205A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27003
SUBJECT: GRB 200205A = Swift J0840.7-3516: optical photometry in Chilescope observatory
DATE:    20/02/06 18:31:31 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

E. Mazaeva (IKI), A. Pozanenko (IKI), M. Krugov (AFIF),  A. Volnova 
(IKI), S. Belkin (IKI) report on behalf of IKI-FuN follow-up collaboration:

We observed  the newly discovered transient X-ray pulsar  Swift 
J0840.7-3516 (Kennea et al., GCN 27000) initially classified as GRB 
200205A (Evans et al., GCN   26982; Niwano etal., GCN   26987;  Osborne 
et al., GCN  26996). Observation of Chilescope RC-1000 started on Feb. 6 
(UT) 02:13:56 in r'-filter. We detect optical transient (Evans et al., 
GCN 26982; Lipunov et al., GCN 26984; Melandri et al., GCN 26986; 
Malesani et al., GCN 26989).

Preliminary photometry is following.

Date       UT start MJD_mid     Filter Exp.  OT(AB) Err. UL
                     (mid, days)    (s)

2020-02-06 02:13:56 58885.11255 r'     5*600 19.70  0.06 22.1

The photometry is based on nearby stars of APASS catalog
Ref.stars
APASS_id râ€™        err
45257574 15.130    0.014
45257540 14.807    0.061


GRB_name: GRB200205B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27004
SUBJECT: GRB 200205B: ESO/NTT near-infrared imaging
DATE:    20/02/06 22:22:43 GMT
FROM:    Daniele B Malesani at DTU Space  <malesani@space.dtu.dk>

D. B. Malesani (DTU Space), D. M. Russell, P. Saikia, M. C. Baglio (NYU 
Abu Dhabi), report:

The optical counterpart of GRB 200205B (Evans et al., GCN 26993; 
Strausbaugh & Cucchiara, GCN 26995; Vielfaure et al., GCN 26998) was 
observed with the ESO New Technology Telescope equipped with the SofI 
imager on two different epochs during the night of 2020 Feb 5-6. 
Observations were carried out under ESO program 0104.D-0945(A) (PI Russell).

The afterglow is well detected in the first epoch in the J and Ks 
filters, and is marginally detected in the second observation. 
Calibrated to the 2MASS survey, we obtain the following magnitudes (Vega):

K = 18.07 +- 0.10  on Feb 6.164 UT  (0.356 days after the GRB)
J = 19.43 +- 0.10  on Feb 6.145 UT  (0.338 days after the GRB)
J = 20.57 +- 0.33  on Feb 6.368 UT  (0.561 days after the GRB)


GRB_name: GRB200207A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27005
SUBJECT: GRB 200207A: Fermi GBM Final Real-time Localization
DATE:    20/02/07 01:33:15 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 01:22:55 UT on 7 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200207A (trigger 602731380.598244 / 200207058).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 244.1, Dec = -48.3 (J2000 degrees, equivalent to J2000 16h 16m, -48d 17'), with a statistical uncertainty of 3.2 degrees.

The angle from the Fermi LAT boresight is 117.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200207058/quicklook/glg_skymap_all_bn200207058.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200207058/quicklook/glg_healpix_all_bn200207058.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200207058/quicklook/glg_lc_medres34_bn200207058.gif


GRB_name: GRB200205B
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27006
SUBJECT: GRB 200205B: Swift/UVOT Detection
DATE:    20/02/07 02:46:45 GMT
FROM:    Kira Simpson at PSU  <kira.simpson1984@gmail.com>

GRB 200205B: Swift/UVOT Detection

K. K. Simpson (PSU) and P. A. Evans (U. Leicester)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 200205B
352 s after the BAT trigger (Evans et al., GCN Circ. 26993).
A source consistent with the XRT position
(Evans et al. GCN Circ. 26993)
is detected in the initial UVOT exposures.

The preliminary UVOT position is:
    RA  (J2000) =  07:11:09.15 = 107.78812 (deg.)
    Dec (J2000) = -56:29:15.3  = -56.48759 (deg.)
with an estimated uncertainty of 0.42 arc sec. (radius, 90% confidence).

Preliminary detections and 3-sigma upper limits using the UVOT photometric
system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures
are:

Filter         T_start(s)   T_stop(s)      Exp(s)           Mag

white           6386           6586          196          18.92+-0.10
white           383            1042           478          16.81+-0.03
v                  540             733          38             16.88 +/-
0.17
b                  638            833           38             17.74 +/-
0.15
u                  614            808           38             17.25 +/-
0.16
w1                 589           783           38            16.88+-0.20
m2                 564          758           38             17.12 +/- 0.28
w2                 689          1056         46              >17.77

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.11 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB200205A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27010
SUBJECT: Swift J0840.7-3516 (AKA GRB 200205A): Swift-BAT refined analysis
DATE:    20/02/07 15:48:03 GMT
FROM:    Sibasish Laha at GSFC  <sibasish.laha@nasa.gov>

M. Stamatikos (OSU), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), P. A. Evans (U. Leicester),
H. A. Krimm (NSF), S. Laha (GSFC/UMBC),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-239 to T+255 sec from the recent telemetry downlink,
we report further analysis of BAT source Swift J0840.7-3516 (trigger #954304)
(Evans et al., GCN Circ. 26982).  The BAT ground-calculated position is
RA, Dec = 130.168, -35.275 deg which is
   RA(J2000)  =  08h 40m 40.4s
   Dec(J2000) = -35d 16' 30.9"
with an uncertainty of 3.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 94%.

The mask weighted light curve shows some weak emission which started before the source
 came into BAT field of view (which is ~ T-100 sec).
Kennea et al. 2020 (Atel #13452) discuss the properties of this newly discovered X-ray transient.
The lower limit of the duration of the burst as detected by BAT is ~ 200 sec.
The source went out of BAT field of view at ~T+260 sec, with a possibility of continuing emission
which may be detected by other telecopes.


The time-averaged spectrum from -81.88 to 132.86 sec is best fit by a power law
with an exponential cutoff.  This fit gives a photon index 0.84 +- 0.91,
and Epeak of 31.5 +- 8.4 keV (chi squared 67.17 for 56 d.o.f.).  For this
model the total fluence in the 15-150 keV band is (1.3 +- 0.1) x 10^-06 erg/cm2
and the 1-sec peak flux measured from T-81.90 sec in the 15-150 keV band is
0.3 +- 0.2 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 2.26 +- 0.17 (chi squared 77.17 for 57 d.o.f.).  All the quoted errors
are at the 90% confidence level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/954304/BA/


GRB_name: GRB200208A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27011
SUBJECT: GRB 200208A: Fermi GBM Final Real-time Localization
DATE:    20/02/08 01:24:33 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 01:14:17 UT on 8 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200208A (trigger 602817262.086318 / 200208052).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 26.7, Dec = 25.3 (J2000 degrees, equivalent to J2000 01h 46m, 25d 18'), with a statistical uncertainty of 6.2 degrees.

The angle from the Fermi LAT boresight is 59.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200208052/quicklook/glg_skymap_all_bn200208052.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200208052/quicklook/glg_healpix_all_bn200208052.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200208052/quicklook/glg_lc_medres34_bn200208052.gif


GRB_name: GRB200205B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27012
SUBJECT: GRB 200205B: Swift-BAT refined analysis
DATE:    20/02/08 02:03:36 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

T. N. Ukwatta (LANL), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), P. A. Evans (U Leicester),
H. A. Krimm (NSF), S. Laha (GSFC/UMBC),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU) (i.e. the Swift-BAT team):

Using the data set from T-239 to T+1361 sec from the recent telemetry
downlink,
we report further analysis of BAT GRB 200205B (trigger #954519 and #954520)
(Evans et al., GCN Circ. 26993). We have combined the data from two
triggers (#954519 and #954520) for the analysis. All the times in this
circular
are relative to the trigger time from #954519.

The BAT ground-calculated position is
RA, Dec = 107.760, -56.488 deg which is
   RA(J2000)  =  07h 11m 02.3s
   Dec(J2000) = -56d 29' 18.1"
with an uncertainty of 1.8 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 47%.

The mask-weighted light curve shows several pulses that start from
~T+20 s and end at ~T+550 s. The first prominent pulse occurs at ~T+60 s,
followed by another significant structure with several overlapping pulses
from ~T+380 s to ~T+520 s. There is a data gap from T+63 s to T+160 s,
likely due to problems of saving data because of the double triggers.
T90 (15-350 keV) is 458.0 +- 5.4 sec (estimated error including
systematics).

Because of the data gap for part of the first pulse, we performed
the time-averaged spectrum for the interval of the second multi-pulse
structure
from T+387.008 to T+520.396 sec. This interval is best fit by a power law
with
an exponential cutoff. This fit gives a photon index 1.36 +- 0.22,
and Epeak of 65.6 +- 10.8 keV (chi squared 41.92 for 56 d.o.f.).  For this
model the total fluence in the 15-150 keV band is 5.4 +- 0.2 x 10^-6 erg/cm2
and the 1-sec peak flux measured from T+438 sec in the 15-150 keV band is
2.0 +- 0.2 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 1.84 +- 0.05 (chi squared 58.00 for 57 d.o.f.).  All the quoted errors
are at the 90% confidence level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/954519/BA/


GRB_name: GRB200120A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27025
SUBJECT: GRB 200120A: Fermi GBM observation
DATE:    20/02/09 02:01:37 GMT
FROM:    Rachel Hamburg at UAH  <rkh0007@uah.edu>

R. Hamburg (UAH) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 23:04:55.34 UT on 20 January 2020, the Fermi Gamma-Ray Burst Monitor
(GBM)
triggered and located GRB 200120A (trigger 601254300 / 200120962).
GRB 200120A was also detected by Insight/HMXT (GCN 26840) and AstroSat/CZTI
(GCN 26851), and localized by the IPN (GCN 26856).

Approximately 820 s after the GBM trigger, SRG/eRosita detected and
localized
an X-ray transient consistent with being the afterglow of GRB 200120A
(Weber et al. 2019, GCN 26988). The Fermi GBM Final Real-time
Localization (GCN 26831) is consistent with the SRG/eRosita position.

The angle from the Fermi LAT boresight at the GBM trigger time is 148
degrees.

The GBM light curve shows a broad, single-peaked structure
with a duration (T90) of about 13 s (50-300 keV).
The time-averaged spectrum from T0-6. to T0+10. s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -0.92 +/- 0.10 and
the cutoff energy, parameterized as Epeak, is 239 +/- 22 keV.

The event fluence (10-1000 keV) in this time interval is
(9.4 +/- 0.4)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+3.0 s in the 10-1000 keV band
is 13 +/- 1 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support
Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB200205B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27027
SUBJECT: GRB 200205B: Chilescope optical observations
DATE:    20/02/09 13:51:47 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

E. Mazaeva (IKI), A. Pozanenko (IKI), M. Krugov (AFIF),  A. Volnova 
(IKI), S. Belkin (IKI) report on behalf of IKI-FuN follow-up collaboration:

We observed  the Swift GRB 200205B (Evans et al., GCN 26993)  with 
Chilescope RC-1000 started on Feb. 7 (UT) 03:04:55 in r'-filter. We 
marginally detect optical afterglow (Lipunov et al., GCN 26991; Evans et 
al., GCN 26993;   Strausbaugh  et al., GCN 26995; Vielfaure et al., GCN 
26998; Malesani et al., GCN 27004; Simpson et al., GCN 27006).

Preliminary photometry is following.

Date       UT start MJD_mid     Filter Exp.   OT(AB) S/N UL
                     (mid, days)    (s)

2020-02-07 03:04:55 1.33613     r'     2*1200 22.2   2.0 22.0

The photometry is based on nearby stars from the SkyMapper catalog
SkyMapper_id    r
293365688    17.550
293359963    16.213
293359881    15.816
293365677    17.659


GRB_name: GRB200207A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27029
SUBJECT: GRB 200207A: AstroSat CZTI detection
DATE:    20/02/10 10:08:46 GMT
FROM:    Ramkrishna Gaikwad at IUCAA/AstroSat  <ramkrishna@iucaa.in>

R. Gaikwad, S. Gupta, V. Sharma and D. Bhattacharya (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data showed a weak detection of long GRB 200207A, which was also detected by Fermi GBM Final Real-time Localization (GCN #27005) and Global MASTER-Net (Lipunov V. et al., GCN #27009).

The source was clearly detected in the 40-200 keV energy range. The light curve showed a single peak of emission peaking at 2020-02-07 01:22:55.0 UT. The measured peak count rate associated with the burst is 146 +/- 23.0 cts/s above the background in the combined data of four quadrants, with a total of 641 +/- 14.9 cts. The local mean background count rate was 534 +/- 1.1 cts/s. Using cumulative rates, we measure a T90 of 9.2 +/- 0.04 s.

It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.

CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.


GRB_name: GRB200211A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27031
SUBJECT: GRB 200211A: Fermi GBM Final Real-time Localization
DATE:    20/02/11 07:36:48 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 07:26:28 UT on 11 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200211A (trigger 603098793.826514 / 200211310).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 345.2, Dec = -7.2 (J2000 degrees, equivalent to J2000 23h 00m, -7d 12'), with a statistical uncertainty of 1.0 degrees.

The angle from the Fermi LAT boresight is 68.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200211310/quicklook/glg_skymap_all_bn200211310.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200211310/quicklook/glg_healpix_all_bn200211310.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200211310/quicklook/glg_lc_medres34_bn200211310.gif


GRB_name: GRB200211A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27032
SUBJECT: GRB 200211A: BALROG localization (Fermi Trigger 603098793 / GRB 200211310)
DATE:    20/02/11 07:53:58 GMT
FROM:    Jochen Greiner at MPE,Garching  <jcg@mpe.mpg.de>

B. Biltzinger, F. Kunzweiler, F. Berlato, J. Burgess & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
603098793 at 07:26:28 on 11 Feb. 2020 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).

The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 344.6+/-0.9 deg
Decl.(2000.0) = -5.6+/-0.8 deg
We estimate an additional systematic error of 1 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB200211310/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB200211310/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB200211310/json

                        


GRB_name: GRB200205B
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27034
SUBJECT: Konus-Wind observation of GRB 200205B
DATE:    20/02/11 13:05:44 GMT
FROM:    Anastasia Tsvetkova at Ioffe Institute  <tsvetkova@mail.ioffe.ru>

A. Tsvetkova, S. Golenetskii, R.Aptekar, D. Frederiks,
M. Ulanov, D. Svinkin, A. Lysenko, A. Ridnaia and T. Cline
on behalf of the Konus-Wind team, report:

The long GRB 200205B which triggered Swift/BAT
at T0=T0(BAT)=19:21:43 UT
(Swift/BAT detection: Evans et al., GCN 26993;
Ukwatta et al., GCN 27012;)
was detected by Konus-Wind in the waiting mode.

The burst light curve shows two emission episodes:
the first pulse lasts from ~T0+48.6 s to ~T0+89.8 s,
and the second pulse lasts from ~T0+390.1 s to ~T0+525.5 s.
The total duration of the burst is ~477 s.

As observed by Konus-Wind, the burst had a fluence of
1.12(-0.05,0.26)x10^-5 erg/cm2 and a 2.944-s peak flux,
measured from ~T0(BAT)+437.202 s, of 1.55(-0.09,+0.44)x10^-7 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

Fitting the K-W 3-channel spectrum o the initial pulse
(from ~T0(BAT)+48.594 s to ~T0(BAT)+89.810 s)
in the 20 keV - 1.5 MeV range
by a simple power law model yields
the PL index = 2.34(-0.06,+0.17),
chi2 = 2.95 / 1 dof.

Modelling the K-W 3-channel spectrum of the second pulse
(from ~T0(BAT)+390.098 s to ~T0(BAT)+446.034 s)
in the 20 keV - 1.5 MeV range
by a power law with exponential cutoff model
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) yields
alpha = -1.32(-0.59,+2.70),
and Ep =87(-17,+13) keV.

Assuming the redshift z=1.465 (Vielfaure et al., GCN 26998)
and a standard cosmology model with H_0 = 67.3 km/s/Mpc,
Omega_M = 0.315, and Omega_Lambda = 0.685 (Planck Collaboration, 2014),
we estimate the following rest-frame parameters:
the isotropic energy release E_iso is ~6.5x10^52 erg,
the peak luminosity L_iso is ~2.2x10^51 erg/s,
and the rest-frame peak energy of the initial pulse spectrum,
Ep,z, is ~ 214 keV.

All the quoted errors are estimated at the 1 sigma confidence level.
All the presented results are preliminary.

The K-W light curve of this burst is available at
http://www.ioffe.rssi.ru/LEA/GRBs/GRB200205B/


GRB_name: GRB200131A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27035
SUBJECT: GRB 200131A: Tautenburg observations
DATE:    20/02/11 15:39:37 GMT
FROM:    Sylvio Klose at TLS Tautenburg  <klose@tls-tautenburg.de>

B. Stecklum, S. Klose, A. Nicuesa Guelbenzu, and C. Hoegner (all Tautenburg) 
report:

We observed the field of GRB 200131A (T0=22:41:15 UT; Sbarufatti et al., GCN 
26953) with the Tautenburg 1.34m Schmidt telescope equipped with the TAUKAM 6k 
x 6k CCD camera and the wide V-band filter (VB). The transmission curve of this 
filter closely follows the Gaia GBP filter.

Based on several Gaia DR2 stars in the field within 1 arcmin radius about the 
afterglow position, we measure for the optical transient (Lipunov et al., GCN 
26954; Butler et al., GCN 26957; Strausbaugh et al., GCN 26959; Gokuldass et 
al., GCN 26960; Kuin et al., GCN 26962; Pozanenko et al., GCN 26964, 26965; 
Watson et al., GCN 26977) the following Vega magnitudes:

mean time t = Jan 31, 23:12:15 UT; t-T0 = 00h 31m 00s;  VB = 18.00 +/- 0.10
mean time t = Feb 01, 20:41:47 UT; t-T0 = 22h 00m 32s;  VB = 21.85 +/- 0.30.


GRB_name: GRB200212A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27037
SUBJECT: GRB 200212A: Fermi GBM Final Real-time Localization
DATE:    20/02/12 11:00:06 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely SHORT GRB

At 10:49:49 UT on 12 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200212A (trigger 603197394.1517 / 200212451).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 126.9, Dec = 8.8 (J2000 degrees, equivalent to J2000 08h 27m, 8d 48'), with a statistical uncertainty of 17.9 degrees.

The angle from the Fermi LAT boresight is 94.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200212451/quicklook/glg_skymap_all_bn200212451.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200212451/quicklook/glg_healpix_all_bn200212451.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200212451/quicklook/glg_lc_medres34_bn200212451.gif


GRB_name: GRB200212A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27040
SUBJECT: GRB 200212A: Fermi GBM Final Localization Correction
DATE:    20/02/12 15:05:40 GMT
FROM:    Andreas von Kienlin at MPE  <azk@mpe.mpg.de>

"The Fermi GBM team reports the detection of a likely Long GRB.

At 10:49:49 UT on 12 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200212A (trigger 603197394.1517 / 200212451). 

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 124.8, Dec = 23.0 (J2000 degrees, equivalent to J2000 08h 19m, 23d 00'), with a statistical uncertainty of 13.7 degrees. 

The angle from the Fermi LAT boresight is 108.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200212451/quicklook/glg_skymap_all_bn200212451.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200212451/quicklook/glg_healpix_all_bn200212451.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200212451/quicklook/glg_lc_medres34_bn200212451.gif"


GRB_name: GRB200215A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27078
SUBJECT: GRB 200215A: Fermi GBM Final Real-time Localization
DATE:    20/02/15 14:49:48 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 14:39:31 UT on 15 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200215A (trigger 603470376.849696 / 200215611).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 30.5, Dec = 10.0 (J2000 degrees, equivalent to J2000 02h 01m, 10d 00'), with a statistical uncertainty of 4.5 degrees.

The angle from the Fermi LAT boresight is 84.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200215611/quicklook/glg_skymap_all_bn200215611.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200215611/quicklook/glg_healpix_all_bn200215611.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200215611/quicklook/glg_lc_medres34_bn200215611.gif


GRB_name: GRB200215A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27079
SUBJECT: GRB 200215A: Swift detection of a burst
DATE:    20/02/15 15:14:13 GMT
FROM:    Kim Page at U.of Leicester  <klp5@leicester.ac.uk>

M. G. Bernardini (INAF-OAB), P. D'Avanzo (INAF-OAB), J.D. Gropp (PSU),
J. A. Kennea (PSU), N. J. Klingler (PSU), H. A. Krimm (NSF),
N. P. M. Kuin (UCL-MSSL), S. Laha (GSFC/UMBC/CRESST),
A. Melandri (INAF-OAB), K. L. Page (U Leicester), D. M. Palmer (LANL),
T. Sbarrato (INAF-OAB) and M. H. Siegel (PSU) report on behalf of the
Neil Gehrels Swift Observatory Team:

At 14:39:31 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 200215A (trigger=956639).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 34.122, +12.781 which is 
   RA(J2000) = 02h 16m 29s
   Dec(J2000) = +12d 46' 50"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve up to T+8s showed a 
single-peaked structure with a duration of about 20 sec.  (The light curve
after T+8s is not immediately available.)  The peak count rate
was ~4000 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 14:40:59.0 UT, 87.1 seconds after
the BAT trigger. Using promptly downlinked data we find a fading,
uncatalogued X-ray source with an enhanced position: RA, Dec 34.0794,
12.7704 which is equivalent to:
   RA(J2000)  = 02h 16m 19.05s
   Dec(J2000) = +12d 46' 13.6"
with an uncertainty of 2.1 arcseconds (radius, 90% containment). This
location is 154 arcseconds from the BAT onboard position, within the
BAT error circle. This position may be improved as more data are
received; the latest position is available at
https://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value (1.21 x
10^21 cm^-2, Willingale et al. 2013), with an excess column of 4.2
(+3.73/-3.12) x 10^21 cm^-2 (90% confidence). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 90 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers none of
the XRT error circle. The 8'x8' region for the list of sources generated
on-board covers 100% of the XRT error circle. The list of sources is typically
complete to about 18 mag. No correction has been made for the expected
extinction corresponding to E(B-V) of 0.15. 

Burst Advocate for this burst is M. G. Bernardini (grazia.bernardini AT brera.inaf.it). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB200215A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27081
SUBJECT: GRB 200215A: Nanshan/NEXT optical upper limit
DATE:    20/02/15 16:08:10 GMT
FROM:    Dong Xu at NAOC/CAS  <dxu@nao.cas.cn>

D. Xu, Z.P. Zhu, X. Liu, B.Y. Yu, Y. Ma (NAOC), X. Gao (Urumqi No.1 
Senior High School) report:

We observed the field of GRB 200215A (Bernardini et al., GCN 27079) 
using the NEXT 0.6m optical telescope located at Nanshan, Xinjiang, 
China. Observations automatically started at 14:40:59 UT on 2002-02-15, 
i.e., 88 s after the BAT trigger. We obtained 3x40 s,  4x60 s, and 5x90 
s frames in the Sloan r-filter. Observations then ended due to 
follow-ups of LIGO/Virgo S200213t.

No optical afterglow is detected in our images at the XRT position 
(Bernardini et al., GCN 27079) down to a limiting magnitude of r~18.0, 
calibrated with the nearby PanSTARRS field.


GRB_name: GRB200215A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27083
SUBJECT: GRB 200215A Possible host galaxy in PanSTARRS
DATE:    20/02/15 18:13:07 GMT
FROM:    Alexander Kann at IAA-CSIC  <kann@iaa.es>

D. A. Kann (HETH/IAA-CSIC), and A. de Ugarte Postigo (HETH/IAA-CSIC, 
DARK/NBI) report:

In PanSTARRS imaging of the field of GRB 200215A (Bernardini et al., GCN 
27079), we find a bright, extended object (1".5 x 1".7) at the edge of 
the enhanced XRT error circle given in Bernanrdini et al.

According to the PanSTARRS catalog, the source lies at:

RA = 02:16:19.065 (J2000)
Dec. = +12:46:09.67 (J2000)

The Kron magnitudes in the catalog are given as:

g_PS = 21.73 +/- 0.06,
r_PS = 20.90 +/- 0.07,
i_PS = 20.26 +/- 0.06,
z_PS = 19.89 +/- 0.05,
y_PS = 19.58 +/- 0.10

We suggest this galaxy may be the host galaxy of GRB 200215A, implying a 
low redshift.

There is another clear extended galaxy to the east of this source, the 
relationship between the two is unclear at this time.

Spectroscopy of these galaxies is encouraged.


GRB_name: GRB200215A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27086
SUBJECT: GRB 200215A: Liverpool Telescope upper limits
DATE:    20/02/15 20:37:20 GMT
FROM:    Daniel Perley at Liverpool JMU  <d.a.perley@ljmu.ac.uk>

D. A. Perley and A. M. Cockeram (LJMU) report:

We observed the field of GRB 200215A (Bernardini et al., GCN 27079) with 
the IO:O imager on the 2m robotic Liverpool Telescope between 19:56 and 
20:14 UT on 2019-02-15.  We acquired 3x150s exposures in each of the i 
and z filters.  No counterpart is detected within the XRT error circle 
in either filter.  Calibrating relative to nearby standards from the 
Pan-STARRS 1 catalog, we place upper limits (3-sigma) of:

i > 22.90  (t = 0.2204 days)
z > 21.95  (t = 0.2264 days)











DisclaimerNone


GRB_name: GRB200215A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27087
SUBJECT: GRB 200215A: Fermi GBM detection
DATE:    20/02/15 22:21:54 GMT
FROM:    Suraj Poolakkil at UAH  <sp0076@uah.edu>

S.Poolakkil (UAH) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 14:39:31.85 UT on 15 February 2020, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 200215A (trigger 603470376 / 200215611),
which was also detected by the Swift/BAT (Bernardini et al. 2020, GCN
27079).
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 86
degrees.

The GBM light curve consists of a single bright pulse followed by some
extended emission with a duration (T90) of about 24 s (50-300 keV).
The time-averaged spectrum from T0-4.09 s to T0+5.12 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -0.76 +/- 0.16 and
the cutoff energy, parameterized as Epeak, is 162 +/- 25 keV.

The event fluence (10-1000 keV) in this time interval is
(1.858 +/- 0.175)E-06 erg/cm^2. The 1-sec peak photon flux
measured starting from T0+0.06 s in the 10-1000 keV band
is 3.7 +/- 0.3 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support
Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB200215A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27088
SUBJECT: GRB 200215A: Optical observations form Calar Alto 2.2m
DATE:    20/02/15 23:21:56 GMT
FROM:    Antonio de Ugarte Postigo at IAA-CSIC  <deugarte@iaa.es>

A. de Ugarte Postigo (HETH/IAA-CSIC, DARK/NBI), D. A. Kann,
M. Blazek, F. Agui Fernandez, C. Thoene (all HETH/IAA-CSIC), 
I. Hermelo, B. Arroyo (both CAHA), Y. Ascasibar, A. Gutierrez Adame, 
A. Cayrol Bernardo, A. Rodriguez Ortega, A. Rayo Mato, 
M. Rocamora Bernal, M. A. Diaz Teodori, P. NuÃ±ez Yebra,
S. Ortega Martinez, G Meeus, D. Barba Gonzalez, L Brenes Gil,
J. Ferrer Ereza, H. Garcia Escudero, S. Jaraba GÃ³mez,
D. Lopez Cano, P. Sanchez Alarcon, P Santamarina Guerrero, 
A. Romar Tejeiro (UAM) report:

We observed the field of GRB 200215A (Bernardini et al., GCN 27079) 
with CAFOS on the 2.2m telescope at Calar Alto Observatory, in 
Almeria (Spain). Our observation started at 19:15 UT (4.591 hr after the 
burst) and consisted of 5x720 s in Rc band.

We detect no optical counterpart within the XRT error circle down to a 
3-sigma limit of 24.0 mag.


GRB_name: GRB200215A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27089
SUBJECT: GRB 200215A: Enhanced Swift-XRT position
DATE:    20/02/16 00:34:14 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 3846 s of XRT Photon Counting mode data and 3 UVOT
images for GRB 200215A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 34.07940, +12.77079 which is equivalent
to:

RA (J2000): 02h 16m 19.06s
Dec (J2000): +12d 46' 14.9"

with an uncertainty of 1.5 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB200215A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27090
SUBJECT: GRB 200215A: Swift/UVOT Upper Limits
DATE:    20/02/16 01:29:30 GMT
FROM:    Paul Kuin at MSSL  <npkuin@gmail.com>

N. P. M. Kuin (UCL-MSSL) and M. G. Bernardini (INAF-OAB)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 200215A
90 s after the BAT trigger (Bernardini et al., GCN Circ. 27079).
No optical afterglow consistent with the XRT position (Evans et al. GCN
Circ. 27089) is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC            90          240          147         >20.0
u_FC               302          552          246         >20.0
white               90         7290          581         >21.2
v                  634         5070          294         >18.5
b                  559         7092          294         >19.8
u                  302         6885          481         >20.3
w1                1087         6680          216         >19.2
w2               10534        11091          547         >19.8

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.15 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB200215A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27091
SUBJECT: GRB 200215A: Swift-XRT refined Analysis
DATE:    20/02/16 02:00:45 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

M. Perri (ASDC), V. D'Elia (ASDC), A. D'Ai (INAF-IASFPA), J.A. Kennea
(PSU), A. Tohuvavohu (U. Toronto), B. Sbarufatti (PSU), K.L. Page (U.
Leicester), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester)
and M.G. Bernardini report on behalf of the Swift-XRT team:

We have analysed 7.4 ks of XRT data for GRB 200215A (Bernardini et al.
GCN Circ. 27079), from 72 s to 35.0 ks after the  BAT trigger. The data
comprise 24 s in Windowed Timing (WT) mode (the first 9 s were taken
while Swift was slewing) with the remainder in Photon Counting (PC)
mode. The enhanced XRT position for this burst was given by Evans et
al. (GCN Circ. 27089).

The light curve can be modelled with a power-law decay with a decay
index of alpha=0.93 (+/-0.04).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.47 (+0.18, -0.17). The
best-fitting absorption column is  1.7 (+0.8, -0.5) x 10^21 cm^-2,
consistent with the Galactic value of 1.2 x 10^21 cm^-2 (Willingale et
al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux
conversion factor deduced from this spectrum  is 4.9 x 10^-11 (5.5 x
10^-11) erg cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      1.7 (+0.8, -0.5) x 10^21 cm^-2
Galactic foreground: 1.2 x 10^21 cm^-2
Excess significance: <1.6 sigma
Photon index:      1.47 (+0.18, -0.17)

If the light curve continues to decay with a power-law decay index of
0.93, the count rate at T+24 hours will be 7.5 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 3.6 x
10^-13 (4.1 x 10^-13) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00956639.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB200216A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27097
SUBJECT: GRB 200216A: Fermi GBM Final Real-time Localization
DATE:    20/02/16 09:17:39 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 09:07:25 UT on 16 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200216A (trigger 603536850.030844 / 200216380).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 318.7, Dec = 6.5 (J2000 degrees, equivalent to J2000 21h 14m, 6d 30'), with a statistical uncertainty of 11.4 degrees.

The angle from the Fermi LAT boresight is 68.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200216380/quicklook/glg_skymap_all_bn200216380.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200216380/quicklook/glg_healpix_all_bn200216380.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200216380/quicklook/glg_lc_medres34_bn200216380.gif


GRB_name: GRB200215A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27098
SUBJECT: GRB 200215A: Swift-BAT refined analysis
DATE:    20/02/16 11:49:41 GMT
FROM:    Hans Krimm at NSF/NASA-GSFC  <hkrimm@nsf.gov>

S. D. Barthelmy (GSFC), M. G. Bernardini (INAF-OAB),  H. A. Krimm (NSF),

S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL),

T. Sakamoto (AGU), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-239 to T+963 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 200215A (trigger #956639)
(Bernardini, et al., GCN Circ. 27079).  The BAT ground-calculated position is
RA, Dec = 34.100, 12.775 deg which is
   RA(J2000)  =  02h 16m 24.1s
   Dec(J2000) = +12d 46' 31.7"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 73%.


The mask-weighted light curve shows a single symmetrical peak from roughly

-10 sec to +6 sec, peaking at T+0 sec. T90 (15-350 keV) is 11.7 +- 2.2 sec

(estimated error including systematics).


The time-averaged spectrum from T-9.97 to T+5.37 sec is best fit by a simple

power-law model.  The power law index of the time-averaged spectrum is

1.41 +- 0.09.  The fluence in the 15-150 keV band is 1.1 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T-0.16 sec in the 15-150 keV band
is 2.7 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/956639/BA/


GRB_name: GRB200215A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27099
SUBJECT: GRB 200215A: UKIRT H-band observations
DATE:    20/02/16 11:58:15 GMT
FROM:    Dong Xu at NAOC/CAS  <dxu@nao.cas.cn>

D. Xu, Z.P. Zhu, X. Liu, H.J. Wang, L. Ge (NAOC) report:

We observed the field of GRB 200215A (Bernardini et al., GCN 27079) 
using the United Kingdom Infra-Red Telescope (UKIRT). Observations 
started at 05:02:05 UT on 2020-02-16 (i.e., 14.38 hr after the BAT 
trigger), and 3600 s H-band imagining was obtained.

No afterglow is detected within the Enhanced XRT error circle (Evans et 
al., GCN 27089) in our stacked image down to a limiting magnitude of H~20.0.

 From the PanSTARRS archive, there exists an extended object outside and 
south to the Enhanced XRT error circle by ~5.1 arcsec, as reported in 
Kann & de Ugarte Postigo (GCN 27083). It's thus dubbed PS021619+124609 
here. As the GRB field is in the previous UKIRT H-band survey, we 
performed photometry of PS021619+124609 in both epochs. Any significant 
brightening for PS021619+124609 is ruled out, and we're inclined to 
think it is not related to the GRB.

We thank the great support of the UKIRT staff, in particular Michael Pohlen.


GRB_name: GRB200216B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27101
SUBJECT: GRB 200216B: Fermi GBM Final Real-time Localization
DATE:    20/02/16 13:42:51 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 13:32:34 UT on 16 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200216B (trigger 603552759.75478 / 200216564).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 159.2, Dec = 21.0 (J2000 degrees, equivalent to J2000 10h 36m, 21d 00'), with a statistical uncertainty of 6.5 degrees.

The angle from the Fermi LAT boresight is 78.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200216564/quicklook/glg_skymap_all_bn200216564.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200216564/quicklook/glg_healpix_all_bn200216564.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200216564/quicklook/glg_lc_medres34_bn200216564.gif


GRB_name: GRB200216B
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27102
SUBJECT: GRB 200216B: Swift detection of a burst
DATE:    20/02/16 13:57:44 GMT
FROM:    Paolo D'Avanzo at INAF - OAB  <paolo.davanzo@inaf.it>

P. D'Avanzo (INAF-OAB), M. G. Bernardini (INAF-OAB), J.D. Gropp (PSU),
J. A. Kennea (PSU), N. J. Klingler (PSU), A. Y. Lien (GSFC/UMBC),
T. Sbarrato (INAF-OAB) and A. Tohuvavohu (U Toronto) report on behalf
of the Neil Gehrels Swift Observatory Team:

At 13:32:33 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 200216B (trigger=956824).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 160.461, +19.454 which is 
   RA(J2000) = 10h 41m 51s
   Dec(J2000) = +19d 27' 15"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed one long peak
with a duration of about 30 sec, there is possible evidence for weaker 
emission out to T0+60 seconds. The peak count rate was ~2000 counts/sec 
(15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 13:34:29.0 UT, 115.1 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source with an enhanced position: RA, Dec
160.4343, 19.4757 which is equivalent to:
   RA(J2000)  = 10h 41m 44.23s
   Dec(J2000) = +19d 28' 32.4"
with an uncertainty of 2.0 arcseconds (radius, 90% containment). This
location is 119 arcseconds from the BAT onboard position, within the
BAT error circle. This position may be improved as more data are
received; the latest position is available at
https://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value (2.03 x
10^20 cm^-2, Willingale et al. 2013), with an excess column of 9.9
(+3.22/-2.80) x 10^21 cm^-2 (90% confidence). 

The initial flux in the 2.5 s image was 1.33e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 124 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of
the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. 
The 8'x8' region for the list of sources generated on-board covers 100% of the
XRT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.02. 

Burst Advocate for this burst is P. D'Avanzo (paolo.davanzo AT inaf.it). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB200216B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27103
SUBJECT: GRB 200216B: GMG upper limit
DATE:    20/02/16 14:36:13 GMT
FROM:    Jirong Mao at Yunnan Obs  <jirongmao_obs@ynao.ac.cn>

J. Mao, D.-Q. Wang, and J.-M. Bai (YNAO) report:



We observed the field of GRB 200216B (D'Avanzo et al. GCN circ. 27102) with the 2.4-meter optical telescope at Gao-Mei-Gu (GMG) station of Yunnan Observatories. The observation began at UT 13:46:56, 16th, Feb, 2020, about 14 min after the trigger. We did not detect any optical source in the Swift-XRT error circle. A preliminary measurement provided an upper limit of R~21.8. 


GRB_name: GRB200216B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27104
SUBJECT: GRB 200216B: Nanshan/NEXT early optical upper limit and possible host galaxy
DATE:    20/02/16 15:09:41 GMT
FROM:    Dong Xu at NAOC/CAS  <dxu@nao.cas.cn>

D. Xu, Z.P. Zhu, X. Liu, B.Y. Yu, Y. Ma (NAOC), X. Gao (Urumqi No.1 
Senior High School) report:

We observed the field of GRB 200216B (D'Avanzo et al., GCN 27102) using 
the NEXT 0.6m optical telescope located at Nanshan, Xinjiang, China. 
Observations automatically started at 13:33:46 UT on 2002-02-16, i.e., 
73 s after the BAT trigger. We obtained 3x40 s, 4x60 s, 3x90 s and 
onging 200 s frames in the Sloan r-filter. The altitude for the GRB and 
the weather has been improving.

No optical afterglow is detected in our images at the XRT position 
(D'Avanzo et al., GCN 27102) down to a limiting magnitude of r~20.0.

Meanwhile, we note that there exists a very marginally detected blob 
(thus noise fluctuation not ruled out yet), extended and being 
positionally consistent with the XRT position both in PanSTAR r-band 
field, centred at coordinates: R.A. (J2000) = 10:41:44.23, Dec. (J2000) 
= +19:28:33.18. The source would be of r~23 in depth, and might be the 
host galaxy of the GRB. Deep imaging would identify the nature of the blob.


GRB_name: GRB200215A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27105
SUBJECT: GRB 200215A: RATIR Optical Observations 
DATE:    20/02/16 16:57:12 GMT
FROM:    Alan M Watson at UNAM  <alan@astro.unam.mx>

Alan M. Watson (UNAM), Nat Butler (ASU), Alexander Kutyrev (GSFC),
William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J.
Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI),
Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz
(UCSC), JesÃºs GonzÃ¡lez (UNAM), Carlos RomÃ¡n-ZÃºÃ±iga (UNAM), Harvey
Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (U. Wash.), and Vicki
Toy (UMD) report:

We observed the field of GRB 200215A (Bernardini et al., GCN Circ.
27079) with the Reionization and Transients Infrared Camera (RATIR;
www.ratir.org) on the 1.5m Harold Johnson Telescope at the Observatorio
AstronÃ³mico Nacional on Sierra San Pedro MÃ¡rtir from 2020/02 16.11 to
2020/02 16.23 UTC (11.91 to 14.78 hours after the BAT trigger),
obtaining a total of 1.79 hours exposure in the r and i bands.

For a source within the enhanced Swift-XRT error circle (Evans et al.,
GCN Circ. 27089), in comparison with the SDSS DR9 catalog, we obtain the
following 3-sigma upper limits:

  r > 22.01
  i > 23.15

These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.

We thank the staff of the Observatorio AstronÃ³mico Nacional in San Pedro
MÃ¡rtir.


GRB_name: GRB200216B
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27106
SUBJECT: GRB 200216B: Enhanced Swift-XRT position
DATE:    20/02/16 19:50:33 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 1480 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 200216B, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 160.43469, +19.47516 which is equivalent
to:

RA (J2000): 10h 41m 44.32s
Dec (J2000): +19d 28' 30.6"

with an uncertainty of 1.7 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB200216A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27107
SUBJECT: GRB 200216A: Swift/BAT detection and arcminute localization from GUANO
DATE:    20/02/16 21:19:11 GMT
FROM:    Jamie A. Kennea at PSU/Swift-XRT  <kennea@swift.psu.edu>

James DeLaunay (PSU), Aaron Tohuvavohu (U Toronto), and Jamie Kennea (PSU) report:

Swift/BAT did not trigger on GRB 200216A.

The Fermi/GBM Flight-Position notice, distributed at T0+24 seconds, from 
the Fermi/GBM detected GRB 200216A (GCN. 27096) triggered the Swift 
Mission Operations Center operated Gamma-ray Urgent Archiver for Novel 
Opportunities (GUANO; Tohuvavohu et al. 2020, in prep).

The GUANO is a fully autonomous, extremely low latency, spacecraft 
commanding pipeline designed for targeted recovery of BAT event mode data 
around the times of compelling astrophysical events to enable more 
sensitive GRB searches.

Upon trigger by the Fermi notice, GUANO sent a command to the Swift Burst 
Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from 
[-50,+150] seconds around the time of GRB 200216A.

All the requested event mode data was delivered to the ground.

In a ground analysis of the data, using the normal BAT imaging technique, 
we detect GRB 200216A with a SNR of 7.5.

With a more sophisticated maximum likelihood analysis (DeLaunay et al., 
2020 in prep.) on the event-mode data we detect GRB 200216A more 
confidently, with a square root of the test statistic (sqrt(TS)) of 15.4. 
The sqrt(TS) behaves similarly to SNR.

The BAT ground-calculated position is
RA, Dec = 311.4378, -11.6580 deg which is
   RA(J2000)  = 311d 26' 16.08"
   Dec(J2000) = -11d 39' 28.8"
with an uncertainty of 3 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 40%.

This arcminute location is consistent with the localization region 
distributed by the Fermi/GBM team (GCN. 27096).

No XRT or UVOT follow-up will take place due to the source's proximity to 
the sun (1.2 hours). We encourage follow-up from instruments capable of 
observing near the sun.


GRB_name: GRB200216B
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27108
SUBJECT: GRB 200216B: Swift/UVOT Upper Limits
DATE:    20/02/16 22:15:58 GMT
FROM:    Paul Kuin at MSSL  <npkuin@gmail.com>

N. P. M. Kuin (UCL-MSSL) and P. D'Avanzo (INAF-OAB) report on
behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 200216B
124 s after the BAT trigger (D'Avanzo et al., GCN Circ. 27102). No optical
afterglow consistent with the XRT position (Goad et al. GCN Circ. 27106)
is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC           124          274          147         >21.0
white              124         1535          334         >21.5
w1                1095         1635           39         >20.2

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB200216B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27109
SUBJECT: GRB 200216B: Fermi GBM observation
DATE:    20/02/16 23:24:33 GMT
FROM:    Christian Malacaria at NASA-MSFC/USRA  <cmalacaria@usra.edu>

C. Malacaria (NASA-MSFC/USRA), B. Mailyan (UAH) and C. Meegan (UAH), 
report on behalf of the Fermi GBM Team:

"At 13:32:34.75 UT on 16 February 2020, the Fermi 
Gamma-ray Burst Monitor (GBM)
triggered and located GRB 200216B (trigger 603552759 / 200216564), 
which also triggered the Swift/BAT (D'Avanzo et al. 2020, GCN 27102).
The Fermi GBM Final Real-time Localization (GCN 27101) 
is consistent with the Swift position.

The angle from the Fermi LAT boresight is 78 degrees.

The GBM light curve consists of a single bright pulse followed by 
some extended emission with a duration (T90)
of about 12.0 s (10-1000 keV). The time-averaged spectrum 
from T0-1.0 to T0+15.4 s is best fit by by a power law function 
with an exponential high-energy cutoff.
The power law index is 0.07 +/- 0.30, and
the cutoff energy, parameterized as Epeak, is 69.5 +/- 4.9 keV.

The fluence (10-1000 keV) in this time interval 
is (1.141 +/- 0.074)E-06 erg/cm^2.
The 1-sec peak photon flux measured starting from T0+2.3 s 
in the 10-1000 keV band is 1.95 +/- 0.2 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html
For Fermi GBM data and info, please visit the official 
Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/" 


GRB_name: GRB200216B
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27110
SUBJECT: GRB 200216B: z-band limit from NOT
DATE:    20/02/17 01:20:29 GMT
FROM:    Antonio de Ugarte Postigo at IAA-CSIC  <deugarte@iaa.es>

A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), J. Martikainen (NOT and 
U. Helsinki), D. Perley (LJMU), K.E. Heintz (U. Iceland), D. Xu (NAOC),
A. Levan (Radboud U.) report on behalf of a larger collaboration:

We observed the field of GRB 200216B (Fermi GBM team GCN 
27101; Dâ€™Avanzo et al. GCN 27102) with the 2.5 m Nordic Optical 
Telescope equipped with AlFOSC. Observations consisted of 5x200s 
imaging in z-band, with mean epoch 17 Feb 2020 00:11:22 UT 
(10.647 hr after the burst). We do not detect any source within the 
refined XRT error box (Goad et al. GCN 27106) down to a 3-sigma 
limit of z > 23.3 mag.


GRB_name: GRB200216A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27112
SUBJECT: GRB 200216A: Fermi GBM detection
DATE:    20/02/17 06:01:27 GMT
FROM:    Stephen Lesage at Fermi-GBM Team  <sjl0014@uah.edu>

S. Lesage, B. Mailyan, S. Poolakkil, and C. Meegan (all UAH)
report on behalf of the Fermi GBM Team:

"At 09:07:25.03 UT on 16 February 2020, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 200216A (trigger 603536850 / 200216380)
which was also detected via Swift ground analysis (DeLaunay et al. 2020,
GCN 27107)
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 68
degrees.

The GBM light curve consists of a single bright pulse followed by
some extended emission with a duration (T90) of about 8.0 s (10-1000 keV).
The time-averaged spectrum from T0-5.0 s to T0+2.5 s is best fit by
a power law function with an exponential high-energy cutoff.
The power law index is 0.9 +/- 0.9 and
the cutoff energy, parameterized as Epeak, is 180.0 +/- 34.0 keV

The event fluence (10-1000 keV) in this time interval is
(4.4 +/- 0.9)E-07 erg/cm^2.
The 1-sec peak photon flux measured starting from T0-4.16 s
in the 10-1000 keV band is 0.92 +/- 0.1 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support
Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB200215A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27113
SUBJECT: GRB 200215A: CALET Gamma-Ray Burst Monitor detection
DATE:    20/02/17 09:01:26 GMT
FROM:    Valentin Pal'shin at AGU  <val@phys.aoyama.ac.jp>

T. Sakamoto, A. Yoshida, V. Pal'shin, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
Y. Asaoka, S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U),
N. Cannady (GSFC/UMBC), M. L. Cherry (LSU),
S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

The long GRB 200215A (Swift detection: Bernardini et al., GCN Circ. 27079,
Barthelmy et al., GCN Circ. 27098; Fermi GBM detection: Poolakkil and
Meegan, GCN Circ. 27087) triggered the CALET Gamma-ray Burst Monitor
(CGBM) at 14:39:28.087 UTC on 15 February 2020.
The burst signal was seen by all CGBM detectors.

The burst light curve shows a multi-peaked structure which starts
at T+0.1 sec, peaks at T+4.0 sec and ends at T+8.3 sec.
The T90 and T50 durations measured by the SGM data are 7.1 +- 1.6 sec
and 2.2 +- 1.5 sec (40-1000 keV), respectively.

The ground processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1265812510/

The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at the Waseda University.


GRB_name: GRB200216B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27114
SUBJECT: GRB 200216B - possible IR counterpart from VLT
DATE:    20/02/17 11:37:45 GMT
FROM:    Andrew Levan at U.of Leicester  <a.levan@astro.ru.nl>

A. J. Levan (Radboud Univ), A. de Ugarte Postigo (HETH/IAA-CSIC, DARK/NBI), D. Xu (NAOC), D. A. Kann (HETH-IAA/CSIC), J. P. U. Fynbo (DAWN/NBI/DTU), K. E. Heinz (Univ. Iceland), N. R. Tanvir (Univ. Leicester), G. Pugliese (API, Univ. Amsterdam), D. H. Hartmann (Clemson University) report on behalf of the Stargate Consortium:

"We observed the localisation of GRB 200216B (Dâ€™Avanzo et al. GCN 27102) with the Very Large Telescope and the HAWK-I instrument in the JHK bands beginning on 17 Feb 2020 at 02:44 UT, approximately 13.2 hours after the burst. 

In our K-band images we identify a candidate IR counterpart within the refined XRT localisation (Goad et al. GCN 27106). The location of the source is 

RA(J2000) 10:41:44.28
DEC(J2000) 19:28:31.3

With an uncertainty of ~0.3â€. 

The source has a magnitude of K(AB)~22. The source is not well detected in either the J or H-band observations, but the depths are such that these observations offer limited constraints on the colour of the source. Given the inferred high X-ray column a high redshift origin is unlikely. We cannot make any statements regarding variability at this stage. 

We thank the staff at the VLT, in particular Bin Yang and Trystyn Berg for their work in acquiring these data."


GRB_name: GRB200216B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27117
SUBJECT: GRB 200216B: Swift-BAT refined analysis
DATE:    20/02/17 21:26:59 GMT
FROM:    Hans Krimm at NSF/NASA-GSFC  <hkrimm@nsf.gov>

H. A. Krimm (NSF), S. D. Barthelmy (GSFC),  P. D'Avanzo (INAF-OAB),
S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-239 to T+908 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 200216B (trigger #956824)
(D'Avanzo, et al., GCN Circ. 27102).  The BAT ground-calculated position is
RA, Dec = 160.452, 19.468 deg which is 
   RA(J2000)  =  10h 41m 48.4s 
   Dec(J2000) = +19d 28' 05.5" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 84%.
 
The mask-weighted light curve shows a single bright pulse followed by some
extended emission.  The main pulse has a FRED shape, starting at T-2 sec, peaking
around T+2 sec and decaying by T+18 sec.   Lower-level extended emission with
some weak pulses lasts until around T+100 sec.   T90 (15-350 keV) is 81.3 +- 13.0 sec
(estimated error including systematics).
 
The time-averaged spectrum from -0.72 to +100.33 sec is best fit by a power law
with an exponential cutoff.  This fit gives a photon index 0.81 +- 0.52, 
and Epeak of 47.6 +- 6.6 keV (chi squared 48.83 for 56 d.o.f.).  For this
model the total fluence in the 15-150 keV band is 1.6 +- 0.1 x 10^-6 erg/cm2
and the 1-sec peak flux measured from T+2.80 sec in the 15-150 keV band is
1.5 +- 0.2 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 1.90 +- 0.10 (chi squared 65.47 for 57 d.o.f.).  All the quoted errors
are at the 90% confidence level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/956824/BA/


GRB_name: GRB200216B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27120
SUBJECT: GRB 200216B: Swift-XRT refined Analysis
DATE:    20/02/18 10:07:24 GMT
FROM:    Paolo D'Avanzo at INAF - OAB  <paolo.davanzo@inaf.it>

P. D'Avanzo (INAF-OAB) and P.A. Evans (U. Leicester) report on behalf
of the Swift-XRT team:

We have analysed 1.6 ks of XRT data for GRB 200216B (D'Avanzo et al.
GCN Circ. 27102), from 105 s to 1.7 ks after the  BAT trigger. The data
comprise 90 s in Windowed Timing (WT) mode (the first 8 s were taken
while Swift was slewing) with the remainder in Photon Counting (PC)
mode. The enhanced XRT position for this burst was given by Goad et al.
(GCN Circ. 27106).

The light curve can be modelled with a power-law decay with a decay
index of alpha=1.91 (+0.07, -0.06).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.18 (+0.20, -0.19). The
best-fitting absorption column is  7.3 (+2.3, -1.9) x 10^21 cm^-2, in
excess of the Galactic value of 2.0 x 10^20 cm^-2 (Willingale et al.
2013). The PC mode spectrum has a photon index of 1.63 (+0.27, -0.26)
and a best-fitting absorption column of 9.2 (+2.9, -2.5) x 10^21 cm^-2.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum  is 5.8 x 10^-11 (8.5 x 10^-11) erg cm^-2
count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      9.2 (+2.9, -2.5) x 10^21 cm^-2
Galactic foreground: 2.0 x 10^20 cm^-2
Excess significance: 6.0 sigma
Photon index:      1.63 (+0.27, -0.26)

If the light curve continues to decay with a power-law decay index of
1.91, the count rate at T+24 hours will be 5.4 x 10^-5 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 3.1 x
10^-15 (4.6 x 10^-15) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00956824.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB200216B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27122
SUBJECT: GRB 200216B: Mondy and AbAO optical upper limits
DATE:    20/02/18 16:01:19 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

A. Pozanenko (IKI), S. Belkin (IKI),  E. Klunko (ISTP),  R. Ya. 
Inasaridze (AbAO), E. Mazaeva (IKI), A. Volnova (IKI),  I. Molotov 
(KIAM) report   on behalf of IKI-GRB-FuN:

We observed the field of  GRB 200216B (D'Avanzo et al.  GCN 27102; Fermi 
GBM team, GCN 27101) with AZT-33IK telescope of Sayan observatory 
(Mondy) starting on Feb. 16  (UT)  13:47:34 i.e. 15 minutes after GRB 
trigger. We also observed the GRB 200216B with AS-32 (0.7m) telescope of 
Abastumani Observatory starting on Feb. 16  (UT)  20:00:20.   We  do not 
detect any  object in the enhanced Swift-XRT position  (Goad et al.  GCN 
27106). In particular we do not detect possible IR-counterpart (Levan et 
al., GCN 27114). Preliminary photometry of the field  is following.

Date       UT start   t-T0       Filter Exp.    OT       UL(3sigma)
                       (mid, days)        (s)

2020-02-16 13:47:34   0.06915     R     30*60   n/d      22.0
2020-02-16 20:00:20   0.29256     R     67*60   n/d      21.8

Photometry is based on the USNO-B2.0 nearby stars.

We note the presense  the optical object at coordinates (J2000) 
10:41:44.54 +19:28:19.3 and brightess of R=21.75 +/- 0.25 at 0.06915 
days (mid time) after triger, and do not detect the object in the secod 
epoch R > 21.8 at 0.29256 days. The object is absent in both SDSS ans 
Pan-SARRS catalogues. The object is apart 14.5 arcsec from center of 
enhanced XRT erro circle (Goad et al.  GCN 27106) and the object lies 
within 90% BAT  ground-calculated position (Krimm  et al., GCN 27117).


GRB_name: GRB200219A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27123
SUBJECT: GRB 200219A: Fermi GBM Final Real-time Localization
DATE:    20/02/19 07:47:13 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely SHORT GRB

At 07:36:49 UT on 19 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200219A (trigger 603790614.095852 / 200219317).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 344.1, Dec = -60.0 (J2000 degrees, equivalent to J2000 22h 56m, -60d 00'), with a statistical uncertainty of 13.9 degrees.

The angle from the Fermi LAT boresight is 48.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200219317/quicklook/glg_skymap_all_bn200219317.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200219317/quicklook/glg_healpix_all_bn200219317.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200219317/quicklook/glg_lc_medres34_bn200219317.gif


GRB_name: GRB200219A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27125
SUBJECT: GRB 200219A: Swift detection of a short burst
DATE:    20/02/19 07:55:10 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

A. Y. Lien (GSFC/UMBC), E. Ambrosi (INAF-IASFPA),
A. D'Ai (INAF-IASFPA), J. A. Kennea (PSU), N. J. Klingler (PSU),
K. L. Page (U Leicester) and D. M. Palmer (LANL) report on behalf of
the Neil Gehrels Swift Observatory Team:

At 07:36:49 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 200219A (trigger=957271).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 342.644, -59.108 which is 
   RA(J2000) = 22h 50m 35s
   Dec(J2000) = -59d 06' 29"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single
peak with a duration of about 1 sec.  The peak count rate
was ~15000 counts/sec (15-350 keV), at ~0.3 sec after the trigger. 

The XRT began observing the field at 07:37:56.6 UT, 67.5 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source with an enhanced position: RA, Dec
342.6376, -59.1200 which is equivalent to:
   RA(J2000)  = 22h 50m 33.02s
   Dec(J2000) = -59d 07' 11.8"
with an uncertainty of 2.5 arcseconds (radius, 90% containment). This
location is 44 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at https://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value (1.93 x
10^20 cm^-2, Willingale et al. 2013), with an excess column of 6.1
(+3.05/-2.63) x 10^21 cm^-2 (90% confidence). 

The initial flux in the 2.5 s image was 4.22e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 74 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of
the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. 
The 8'x8' region for the list of sources generated on-board covers 100% of the
XRT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.02. 

Burst Advocate for this burst is A. Y. Lien (amy.y.lien AT nasa.gov). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB200219A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27126
SUBJECT: GRB 200219A: MASTER catalog automatic possible Host Galaxy candidate
DATE:    20/02/19 09:29:17 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

N.Tiurina, V. Lipunov, E. Gorbovskoy, V.Kornilov, 
P.Balanutsa,A.Kuznetsov, V. Vladimirov, O.Gress, D. Vlasenko, F.Balakin, 
I.Gorbunov, D.Zimnukhov, 
V.Senik, T.Pogrosheva, D. Kuvshinov, V.Shumkov (Lomonosov Moscow State 
University, SAI, Physics  Department),

R. Rebolo, M. Serra(The Instituto de Astrofisica de Canarias),

R. Podesta, C.Lopez, F. Podesta, C.Francile(Observatorio Astronomico Felix 
Aguilar OAFA),

H. Levato(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio 
ICATE),

O.A. Gres, N.M. Budnev, O.Ershova (Irkutsk State University, API),

V. Yurkov, A. Gabovich, Yu. Sergienko(Blagoveschensk Educational State 
University)

MASTER Global Robotic Net Catalog System  (http://observ.pereplet.ru, 
Lipunov et 
al.,  2010,Advances in Astronomy,v. 2010, 30L)
reducted  GRB 200219A (Lien et al. GCN 27125, Lipunov et al GCN 
27124) XRT error box.

It found possible Host Galaxy in 1 sec from XRT center error box:

   The Guide Star Catalog,   WISE All-Sky Data Release (Cutri+ 
2012)  AllWISE Data Release (Cutri+ 2013), The VISTA Hemisphere Survey 
(VHS) catalog DR4.1 (McMahon+, 2013)

RA,DEC (AllWISE) coordinates
22 50 33.023904 -59 07 10.83396

This message can be used.


GRB_name: GRB200219B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27127
SUBJECT: GRB 200219B: Fermi GBM Final Real-time Localization
DATE:    20/02/19 10:04:32 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 09:54:14 UT on 19 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200219B (trigger 603798859.677708 / 200219413).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 299.1, Dec = 6.7 (J2000 degrees, equivalent to J2000 19h 56m, 6d 42'), with a statistical uncertainty of 4.0 degrees.

The angle from the Fermi LAT boresight is 46.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200219413/quicklook/glg_skymap_all_bn200219413.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200219413/quicklook/glg_healpix_all_bn200219413.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200219413/quicklook/glg_lc_medres34_bn200219413.gif


GRB_name: GRB200216B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27128
SUBJECT: GRB 200216B: second epoch optical upper limit at Mondy observatory
DATE:    20/02/19 12:01:00 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

S. Belkin (IKI), A. Pozanenko (IKI), E. Klunko (ISTP), E. Mazaeva (IKI), 
A. Volnova (IKI) report on behalf of IKI-GRB-FuN:

We observed the field of GRB 200216B (D'Avanzo et al., GCN 27102: Fermi 
GBM team, GCN 27101) with AZT-33IK telescope of Sayan observatory 
(Mondy) starting on Feb. 18 (UT) 16:02:31. We did not detect any object 
in the enhanced Swift-XRT position (Goad et al., GCN 27106). In 
particular we do not detect possible IR-counterpart (Levan et al., GCN 
27114). Upper limit is 22.8R.

We detected the object reported earlier (Pozanenko et al., GCN 27122) 
with coordinates (J2000) 10:41:44.54 +19:28:19.3  which is 14.5 arcsec 
apart from center of enhanced XRT error circle (Goad et al., GCN 27106). 
  Preliminary photometry of the object is following:

Date       UT start   t-T0       Filter Exp.    OT   Err.    UL(3sigma)
                        (mid, days)             (s)

2020-02-18 16:02:31   2.12497     R     30*120   22.7 0.3    22.8


Power law index of a light curve of the object calculated between the 
two epochs is about -0.3. Therefore the object might not be related to 
GRB 200216B.


GRB_name: GRB200219A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27137
SUBJECT: GRB 200219A: Fermi GBM observation
DATE:    20/02/19 16:35:50 GMT
FROM:    Elisabetta Bissaldi at INFN,Bari  <elisabetta.bissaldi@ba.infn.it>

E. Bissaldi (Politecnico and INFN Bari) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:


"At 07:36:49.10 UT on 19 February 2020, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 200219A (trigger 603790614/200219317),
which was also detected by the Swift/BAT (Lien et al. 2020, GCN 27125).
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 49 degrees.

The GBM light curve consists of a single emission episode
with a duration (T90) of about 1.1 s (50-300 keV).
The time-averaged spectrum from T0-0.064 s to T0+0.448 s is
adequately fit by a power law function with an exponential
high-energy cutoff. The power law index is -0.60 +/- 0.06 and
the cutoff energy, parameterized as Epeak, is 1.4 +/- 0.2 MeV.

The event fluence (10-1000 keV) in this time interval is
(2.8 +/- 0.1)E-06 erg/cm^2. The 64-ms peak photon flux measured
starting from T0+0.192 s in the 10-1000 keV band
is 16.1 +/- 1.1 ph/s/cm^2.


The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB200219A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27138
SUBJECT: GRB 200219A: Enhanced Swift-XRT position
DATE:    20/02/19 16:48:09 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 1921 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 200219A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 342.63837, -59.11954 which is equivalent
to:

RA (J2000): 22h 50m 33.21s
Dec (J2000): -59d 07' 10.4"

with an uncertainty of 1.8 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB200219A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27139
SUBJECT: GRB 200219A: Swift-XRT refined Analysis
DATE:    20/02/19 16:50:13 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

V. D'Elia (ASDC), A. D'Ai (INAF-IASFPA), A. Tohuvavohu (U. Toronto), B.
Sbarufatti (PSU), D.N. Burrows (PSU), A.P. Beardmore (U. Leicester),
P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester), A. Melandri
(INAF-OAB) and A.Y. Lien report on behalf of the Swift-XRT team:

We have analysed 6.7 ks of XRT data for GRB 200219A (Lien et al. GCN
Circ. 27125), from 57 s to 13.6 ks after the  BAT trigger. The data
comprise 28 s in Windowed Timing (WT) mode (the first 8 s were taken
while Swift was slewing) with the remainder in Photon Counting (PC)
mode. The enhanced XRT position for this burst was given by Osborne et
al. (GCN Circ. 27138). We cannot determine at the present time whether
the source is fading.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00957271.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB200219A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27142
SUBJECT: GRB 200219A: Swift-XRT refined Analysis correction
DATE:    20/02/19 19:03:51 GMT
FROM:    Elena Ambrosi at INAF-IASF  <elena.ambrosi@inaf.it>

A. D'Ai (INAF-IASFPA), B. Sbarufatti (PSU), D.N. Burrows (PSU), J. D.
Gropp (PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A.
Melandri (INAF-OAB), T. Sbarrato (INAF-OAB) and A. Y. Lien (GSFC/UMBC)
report on behalf of the Swift-XRT team:

We have analysed 9.8 ks of XRT data for GRB 200219A (Lien et al. GCN
Circ. 27125), from 57 s to 24.9 ks after the  BAT trigger. The data
comprise 165 s in Windowed Timing (WT) mode (the first 8 s were taken
while Swift was slewing) with the remainder in Photon Counting (PC)
mode. The enhanced XRT position for this burst was given by Osborne et
al. (GCN Circ. 27138).

The light curve can be modelled with a series of power-law decays. The
initial decay index is alpha=1.10 (+/-0.16). At T+136 s  the decay
steepens to an alpha of 4.7 (+3.3, -0.4) before breaking again at T+444
s to a final decay with index alpha=1.2 (+0.4, -0.6).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.36 (+/-0.06). The
best-fitting absorption column is  1.26 (+0.26, -0.24) x 10^21 cm^-2,
in excess of the Galactic value of 1.9 x 10^20 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 4.9 x 10^-11 (5.4 x 10^-11) erg
cm^-2 count^-1. 

A summary of the WT-mode spectrum is thus:
Total column:      1.26 (+0.26, -0.24) x 10^21 cm^-2
Galactic foreground: 1.9 x 10^20 cm^-2
Excess significance: 7.2 sigma
Photon index:      1.36 (+/-0.06)

If the light curve continues to decay with a power-law decay index of
1.2, the count rate at T+24 hours will be 2.1 x 10^-4 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.0 x
10^-14 (1.1 x 10^-14) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00957271.

Due to data delivery problems, the GCN Circ. 27139 (D'Elia et al.) was
sent while the analysis was still running, which is why it was
incomplete.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB200219B
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27144
SUBJECT: LIGO/Virgo S200219ac: Fermi GBM transient event not confidently associated with GW signal
DATE:    20/02/19 21:57:24 GMT
FROM:    Rachel Hamburg at UAH  <rkh0007@uah.edu>

R. Hamburg (UAH) reports on behalf of the Fermi-GBM Team:

For S200219ac and using the initial BAYESTAR skymap, Fermi-GBM was
observing 46.6% of the localization probability at event time; the southern
lobe was Earth-occulted for GBM.

There was a Fermi-GBM onboard trigger, GRB 200219B (GCN 27127),
approximately 10 min after the LIGO/Virgo detection of the GW trigger (GCN
27130). However due to the temporal offset and spatial inconsistency, we do
not consider these two events associated. An automated, blind search for
short gamma-ray bursts below the onboard triggering threshold in Fermi-GBM
also identified no counterpart candidates +/- 1 hour around the GW event
time.

The GBM targeted search, the most sensitive, coherent search for GRB-like
signals, was run from +/-30 s around merger time for S200219ac. The
targeted search identified a transient at approximately T0+11 s that is
consistent with a short GRB origin and spatially consistent with the
initial S200219ac localization map. The SNR of this event is 5.6, and the
False Alarm Rate for signals of this significance in GBM data is 3.0E-4 Hz.
However, due to the weak nature of the event, the rate of events of similar
significance in GBM, and the presence of multiple galactic transient
signals around the time of interest, we are not confident in an association.

For the interested observer, the GBM localization HEALPix file can be found
on the Gravitational Wave Treasure Map (Wyatt et al. 2020,
arXiv:2001.00588) at:
http://treasuremap.space/static/S200219ac_GBM_Event1_healpix.fit.
The skymap image can be found at:
http://treasuremap.space/static/S200219ac_GBM_Event1_skymap.png.


GRB_name: GRB200219C
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27145
SUBJECT: GRB 200219C: Fermi GBM Final Real-time Localization
DATE:    20/02/20 00:07:23 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 23:57:10 UT on 19 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200219C (trigger 603849435.33311 / 200219998).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 264.5, Dec = 8.4 (J2000 degrees, equivalent to J2000 17h 37m, 8d 24'), with a statistical uncertainty of 1.0 degrees.

The angle from the Fermi LAT boresight is 43.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200219998/quicklook/glg_skymap_all_bn200219998.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200219998/quicklook/glg_healpix_all_bn200219998.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200219998/quicklook/glg_lc_medres34_bn200219998.gif


GRB_name: GRB200219A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27148
SUBJECT: GRB 200219A, Swift-BAT refined analysis
DATE:    20/02/20 04:14:14 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

S. Laha (GSFC/UMBC), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), H. A. Krimm (NSF),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
J. P. Norris (BSU), D. M. Palmer (LANL),
T. Sakamoto (AGU), M. Stamatikos (OSU),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-240 to T+962 sec from the recent telemetry
downlink,
we report further analysis of BAT GRB 200219A (trigger #957271)
(Lien et al., GCN Circ. 27125).  The BAT ground-calculated position is
RA, Dec = 342.595, -59.101 deg which is
   RA(J2000)  =  22h 50m 22.7s
   Dec(J2000) = -59d 06' 04.5"
with an uncertainty of 2.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 99%.

The mask-weighted light curve shows a short pulse that starts and peaks at
~T0,
and ends at ~T+0.5 s. It is followed by an extended emission that lasting
until ~T+90 s. In addition, there may be some even weaker emission until
~T+300 s.
T90 (15-350 keV) is 288.0 +- 50.6 sec (estimated error including
systematics).

The time-averaged spectrum from T-0.2 to T+86.7 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.47 +- 0.25.  The fluence in the 15-150 keV band is 7.4 +- 1.1 x 10^-7
erg/cm2.
The 1-sec peak photon flux measured from T-0.268 sec in the 15-150 keV band
is 2.4 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

Because the burst seems to be similar to short GRBs with extended emission,
we perform further spectral analysis for the short pulse and the extended
emission. The short pulse from T-0.224 s to T+0.496 s (determined by the
Bayesian block analysis) is best fit by a simple power-law model.
The power law index of the time-averaged spectrum is 0.69 +- 0.14. The
fluence in the 15-150 keV band is 2.5 +- 0.2 x 10^-7 erg/cm2.
The extended emission from T+0.496 s to T+86.704 s is best fit by a
simple power-law model. The power law index of the time-averaged
spectrum is 1.78 +- 0.33.  The fluence in the 15-150 keV band is
4.9 +- 1.0 x 10^-7 erg/cm2.

The spectral lag of the short pulse is 14 (+5, -5) ms for the 100-350 keV
to 25-50 keV bands, and 20 (+15, -10) ms for the 50-100 keV to 15-25 keV
bands. These values are more consistent with those of long GRBs.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/957271/BA/


GRB_name: GRB200215A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27150
SUBJECT: GRB 200215A: LCO Optical Upper Limits
DATE:    20/02/20 05:44:06 GMT
FROM:    Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh@uvi.edu>

R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (U. of the Virgin Islands/College of Marin) report on behalf of a larger collaboration:

We observed Swift GRB 200215A (Bernardini et al., GCN 27079) with the LCO 1-m Sinistro instrument at the McDonald Observatory, Texas, USA site, on February 16, from 01:37 to 01:46 UT (corresponding to 10.97 to 11.12 hours from the GRB trigger time) with the Bessel I filter.

We performed a series of 3x120s exposures. We do not detect any sources in the individual frames (nor in stacked images) in the Swift error region.  Using the USNO-B.1 catalog as reference, we obtain the following 3-sigma upper limit:

I > 18.8

R.S. is funded by NSF AST grant #1831682


GRB_name: GRB200219C
Detection_method: Fermi LAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27151
SUBJECT: GRB 200219C: Fermi-LAT detection
DATE:    20/02/20 07:49:00 GMT
FROM:    Makoto Arimoto at Tokyo Inst of Tech  <arimoto@hp.phys.titech.ac.jp>

F. Dirirsa (Univ. of Johannesburg), M. Arimoto (Kanazawa Univ.), M.
Axelsson (KTH & Stockholm Univ.), F. Longo (University & INFN
Trieste), and N. Omodei (Stanford U.)
report on behalf of the Fermi-LAT Collaboration:

On February 19, 2020, Fermi-LAT detected high-energy emission from
GRB 200219C, which was also detected by Fermi-GBM (trigger
603849435/200219998, GCN 27145).

The best LAT on-ground location is found to be

RA, Dec = 262.7, 10.5 (degrees, J2000)

with an error radius of 0.24 deg (90% containment, statistical error only).
This was 43 deg from the LAT boresight at the time of the GBM trigger:

T0 = 23:57:10.3 UT.

The data from the Fermi-LAT show a significant increase
in the event rate after the GBM trigger that is spatially correlated with the
GBM emission (2.7 degrees from the GBM position) with high significance.
The photon flux above 100 MeV in the time interval 0-1500 s after the
GBM trigger is 2.2 +/- 0.8 e-6 ph/cm2/s.

The estimated photon index above 100 MeV is -2.1 +/- 0.3.

The highest-energy photon is a 1.17 GeV event which is observed 344.6 seconds
after the GBM trigger.

A Swift ToO has been requested for this burst.

The Fermi-LAT point of contact for this burst is
Feraol Fana Dirirsa (fdirirsa@uj.ac.za).

The Fermi-LAT is a pair conversion telescope designed to cover
the energy band from 20 MeV to greater than 300 GeV.
It is the product of an international collaboration between
NASA and DOE in the U.S. and many scientific institutions
across France, Italy, Japan and Sweden.


GRB_name: GRB200219C
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27152
SUBJECT: GRB 200219C: Tiled Swift observations
DATE:    20/02/20 12:01:20 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P. A. Evans (U. Leicester) reports on behalf of the Swift team:

Swift has initiated a series of observations, tiled on the sky, of the
Fermi/LAT GRB 200219C. Automated analysis of the XRT data will
be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00088

Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. The probability of finding
serendipitous sources, unrelated to the Fermi/LAT event is high: any X-ray source
considered to be a probable afterglow candidate will be reported via a GCN Circular
after manual consideration.

Details of the XRT automated analysis methods are detailed in Evans et
al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).

This circular is an official product of the Swift-XRT team.


GRB_name: GRB200219C
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27155
SUBJECT: GRB 200219C: Fermi GBM detection
DATE:    20/02/20 17:06:32 GMT
FROM:    Rachel Hamburg at UAH  <rkh0007@uah.edu>

R. Hamburg (UAH), C. Meegan (UAH) and E. Bissaldi (Politecnico and INFN
Bari)
report on behalf of the Fermi GBM Team:

"At 23:57:10.33 UT on 19 February 2020, the Fermi Gamma-Ray Burst Monitor
(GBM)
triggered and located GRB 200219C (trigger 603849435 / 200219998), which was
also detected by Fermi-LAT (Dirirsa et al. 2020, GCN 27151). The Fermi GBM
Final Real-time Localization (GCN 27145) is consistent with the LAT
position.

The GBM light curve shows a bright main peak followed by a weaker emission
episode and has a duration (T90) of about 22 s (50-300 keV).
The time-averaged spectrum from T0-0.00 s to T0+25.9 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -1.09 +/- 0.03 and
the cutoff energy, parameterized as Epeak, is 199 +/- 9 keV.
A Band function fits the spectrum equally well with
Epeak = 181 +/- 12 keV, alpha = -1.05 +/- 0.03 and beta = -2.50 +/- 0.24.

The event fluence (10-1000 keV) in this time interval is
(1.87 +/- 0.04)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+3.7 s in the 10-1000 keV band
is 24.8 +/- 0.4 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support
Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB200219C
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27156
SUBJECT: GRB 200219C: DDOTI Observations 
DATE:    20/02/20 18:58:16 GMT
FROM:    Alan M Watson at UNAM  <alan@astro.unam.mx>

Alan M. Watson (UNAM), Eleonora Troja (GSFC/UMD), Nat Butler (ASU), 
William H. Lee (UNAM), Simone Dichiara (GSFC/UMD), Alexander Kutyrev
(GSFC/UMD), Margarita Pereyra (UNAM), Rosa L. Becerra (UNAM), Diego
Gonzalez (UNAM), and Tanner Wolfram (ASU) report:

We observed the field of 200219C, detected by both Fermi/GBM (Fermi GBM
Team, GCN Circ. 27145) and Fermi/LAT (Dirirsa et al., GCN Circ. 27151),
with the DDOTI/OAN wide-field imager at the Observatorio Astronomico
Nacional on Sierra San Pedro Martir (http://ddoti.astroscu.unam.mx) on
the night of 2020-02-20 UTC.

We observed from 2020-02-20 11:37 UTC to 2020-02-13 13:08 UTC (from 11.7
to 13.2 hours after the event) obtaining 72 minutes of exposure in the w
filter. We calibrate our images against the APASS catalog. Our 5-sigma
limiting magnitude is w = 20.4.

Comparing our observations to the USNO-B1 and PanSTARRS PS1 DR2
catalogs, we detect no uncatalogued sources in the Fermi/LAT error
region (Dirirsa et al., GCN Circ. 27151) to our 5-sigma limit.

The Fermi/LAT error includes the probably XRT afterglow candidate (Evans
et al., GCN Circ. 27152) at 17:30:02.34 +10:32:22.9 J2000 (source #2
at https://www.swift.ac.uk/xrt_products/TILED_GRB00088/). We see no
evidence for an optical counterpart at this position to our 5-sigma
limit.

We thank the staff of the Observatorio Astronomico Nacional in San Pedro
Martir.


GRB_name: GRB200219C
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27157
SUBJECT: GRB 200219C: Swift-XRT afterglow detection
DATE:    20/02/20 20:10:40 GMT
FROM:    Valerio D'Elia at ASDC  <valerio.delia@ssdc.asi.it>

D.N. Burrows (PSU), J. D. Gropp (PSU), J.A. Kennea (PSU), J.P. Osborne
(U. Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U.
Leicester), A. Melandri (INAF-OAB), T. Sbarrato (INAF-OAB), P. D'Avanzo
(INAF-OAB) and P.A. Evans (U. Leicester) report on behalf of the
Swift-XRT team:

Swift-XRT has performed follow-up observations of the
Fermi/LAT-detected burst GRB 200219C (Dirirsa et al. GCN Circ. 27151)
in a series of observations tiled on the sky. The total exposure time
is 2.4 ks, distributed over 4 tiles; the maximum exposure at a single
sky location was 2.4 ks. The data were collected between T0+43.0 ks and
T0+56.0 ks, and are entirely in Photon Counting (PC) mode. 

Two uncatalogued X-ray sources are detected, of which one ("Source 2")
is above the RASS limit, and is therefore likely the GRB afterglow.
Using 2417 s of PC mode data and 5 UVOT images, we find an enhanced XRT
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 262.50899, +10.53933 which is
equivalent to:

RA (J2000): 17h 30m 02.16s
Dec(J2000): +10d 32' 21.6"

with an uncertainty of 2.1 arcsec (radius, 90% confidence). This
position is 12.9 arcmin from the Fermi/LAT position.  The light curve
is consistent with a constant source of mean count rate 1.1e-01 ct/sec.
A power-law fit gives an index of 0.9 (+1.4, -1.5).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.1 (+/-0.4). The
best-fitting absorption column is  3.2 (+1.6, -1.4) x 10^21 cm^-2, in
excess of the Galactic value of 1.2 x 10^21 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 3.1 x 10^-11 (4.9 x 10^-11) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      3.2 (+1.6, -1.4) x 10^21 cm^-2
Galactic foreground: 1.2 x 10^21 cm^-2
Excess significance: 2.4 sigma
Photon index:      2.1 (+/-0.4)

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00020973.
The results of the full analysis of the tiled XRT observations are
available at https://www.swift.ac.uk/xrt_products/TILED_GRB00088.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB200221A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27159
SUBJECT: GRB 200221A: Fermi GBM Final Real-time Localization
DATE:    20/02/21 04:03:14 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely SHORT GRB

At 03:52:58 UT on 21 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200221A (trigger 603949983.711252 / 200221162).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 157.1, Dec = 33.1 (J2000 degrees, equivalent to J2000 10h 28m, 33d 06'), with a statistical uncertainty of 5.0 degrees.

The angle from the Fermi LAT boresight is 122.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200221162/quicklook/glg_skymap_all_bn200221162.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200221162/quicklook/glg_healpix_all_bn200221162.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200221162/quicklook/glg_lc_medres34_bn200221162.gif


GRB_name: GRB200219C
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27161
SUBJECT: GRB 200219C: Nanshan/NEXT optical upper limit and possible host galaxy from PanSTARRS
DATE:    20/02/21 05:15:46 GMT
FROM:    Dong Xu at NAOC/CAS  <dxu@nao.cas.cn>

D. Xu, X. Liu, Z.P. Zhu, B.Y. Yu, Y. Ma (NAOC), X. Gao (Urumqi No.1 
Senior High School) report:

We observed the field of the possible X-ray afterglow by Swift/XRT 
(Burrows et al., GCN 27157) of GRB 200219C detected by Fermi/GBM and 
Fermi/LAT (GCN 27145; Dirirsa et al., GCN 27151), using the 0.6m NEXT 
telescope located at Nanshan, Xinjiang, China. Observations started at 
22:45:55 UT on 2020-02-20 (i.e., 22.8 h after the Fermi trigger) and 
10x300 s Sloan r-band frames were obtained.

No optical counterpart is detected in our stacked image at the Swift XRT 
position, down to a limiting magnitude of r~21.0.

Inspection of PanSTARRS reveals a faint, extended source within the XRT 
error circle. It's localized at coordinates: R.A. (J2000) = 17:30:02.21, 
Dec.(J2000) = +10:32:22.69, and has r = 22.70 +/- 0.15 mag. Thus is may 
be the host galaxy of the GRB, if the Swift XRT detection is the 
afterglow of the GRB.


GRB_name: GRB200115A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27162
SUBJECT: GRB 200219Ð¡: Mondy and TSHAO optical observations
DATE:    20/02/21 10:54:35 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

I. Reva (FAPHI), A. Pozanenko (IKI), M. Krugov (FAPHI), with Zeiss-1000 
1-m telescope of Tien Shan Astronomical Observatory

A. Pozanenko (IKI), S. Belkin (IKI),  E. Klunko (ISTP), I. Reva (FAPHI), 
  M. Krugov (FAPHI), E. Mazaeva (IKI), A. Volnova (IKI) report on behalf 
of IKI-GRB-FuN:

We observed the field of GRB 200219Ð¡ (The Fermi GBM team, GCN 27145; 
Dirirsa et al., GCN 27151; Hamburg et al., GCN  27155) with AZT-33IK 
1.5-m telescope of Sayan observatory (Mondy) starting on Feb. 20 (UT) 
21:21:45 and with Zeiss-1000 1-m telescope of Tien Shan Astronomical 
Observatory starting on Feb. 20 (UT) 23:17:45. Within enhanced XRT
position of XRT afterglow (Burrows et al., GCN 27157) we detected an 
optical object in coordinates of (J2000) 17:30:02.275 +10:32:22.47 with 
uncertainities of 0.3 arcsec in both coordinates. Coordinates are 
consistent with possible host galaxy (Xu et al., GCN 27161) which is 
presented in  Pan-STARRS catalaog. Preliminary photometry of the object 
is following.

Date UT start t-T0 Filter Exp. OT Err UL(3sigma)   telesope
                         (mid, days) (s)
2020-02-20 21:21:45 0.90596 R 40*60 21.55 0.15 22.2 AZT-33IK
2020-02-20 23:17:45 0.99207 R 56*60 n/d   n/d  21.3 Z-1000

Photometry is based on the USNO-B2.0 nearby stars.
USNO-B1.0    R2
1005-0285285 17.74
1005-0285301 19.23
1005-0285213 19.99

The object is somewhat brighter than that presented in Pan-STARRS DR1, 
and we suggest this object is a candidate for the afterglow of GRB 200115A.


GRB_name: GRB200219C
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27163
SUBJECT: GRB 200219C: CALET Gamma-Ray Burst Monitor detection
DATE:    20/02/21 15:33:14 GMT
FROM:    Valentin Pal'shin at AGU  <val@phys.aoyama.ac.jp>

S. Sugita, A. Yoshida, T. Sakamoto, V. Pal'shin (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
Y. Asaoka, S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U),
N. Cannady (GSFC/UMBC), M. L. Cherry (LSU),
S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

The long GRB 200219C (Fermi GBM detection: Fermi GBM Team,
GCN Circ. 27145, Hamburg et al., GCN Circ. 27155;
Fermi-LAT detection: Dirirsa et al., GCN Circ. 27151;
https://gcn.gsfc.nasa.gov/other/200219C.gcn3)
triggered the CALET Gamma-ray Burst Monitor (CGBM) at 23:57:10.630 UTC
on 19 February 2020. The burst signal was seen by only the SGM detector.

The burst light curve shows a multi-peaked pulse which starts at T+0.1 sec,
peaks at T+1.6 sec and ends at T+4.6 sec. The T90 and T50 durations
measured by the SGM data are 4.0 +- 0.7 sec and 2.1 +- 0.9 sec (40-1000
keV), respectively.

The ground processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1266191565/

The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at the Waseda University.


GRB_name: GRB200219A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27164
SUBJECT: GRB 200219A: FRAM-Auger optical limit
DATE:    20/02/21 16:41:40 GMT
FROM:    Martin Jelinek at Astro.Inst-AVCR,Ondrejov  <martin.jelinek@asu.cas.cz>

Martin Jelinek, Jan Strobl (ASU CAS Ondrejov, CZ),
Martin Masek, Petr Janecek, Sergey Karpov, Jakub
Jurysek, Jan Ebr, Ronan Cunniffe, Petr Travnicek and
Michael Prouza (Institute of Physics, Prague, CZ)

report:

The 30cm robotic telescope FRAM-Auger in Malargue
(Argentina) reacted robotically to the Swift/BAT alert
of GRB200219A (Lien et al., GCNC 27125, D'Elia et al.,
GCNC 27139, and Bissaldi et al., GCNC 27137), starting
with a series of 20s unfiltered images at 07:43:16 UT,
i.e. 6.45 min post trigger.

We do not detect any new or strongly variable source at
or around the reported gamma-ray errorbox at single
frames or a combined 20 x 20s image taken between 6.45
min and 15.39 min after the initial trigger. The
combined exposure has a limiting magnitude r'(AB) =
18.9, as calibrated against the APASS Catalogue.


GRB_name: GRB200219A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27165
SUBJECT: GRB 200219A: UVOT Upper Limits
DATE:    20/02/21 18:02:34 GMT
FROM:    Mike Siegel at PSU/Swift MOC  <mhs18@psu.edu>

M. H. Siegel (PSU) and A. Y. Lien (GSFC/UMBC)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 200219A
75 s after the BAT trigger (Lien et al., GCN Circ. 27125).
No optical afterglow consistent with the XRT position
(Osborne et al. GCN Circ. 27138)
is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC            75          225          147         >20.2
u_FC               287          537          246         >19.3
white               75        19365         1139         >21.2
v                  617        30839         1770         >19.7
b                  543        36572         2257         >20.9
u                  287        25105         2431         >20.7
w1                 666        40797         1248         >20.4
m2                 641        40734         2104         >20.4
w2                 592        28878          914         >20.2

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB200219C
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27166
SUBJECT: GRB 200219C: OAJ afterglow confirmation
DATE:    20/02/21 20:03:17 GMT
FROM:    Alexander Kann at IAA-CSIC  <kann@iaa.es>

M. Blazek, D. A. Kann (both HETH/IAA-CSIC), A. de Ugarte Postigo 
(HETH/IAA-CSIC, DARK/NBI), C. C. Thoene, J. F. Agui Fernandez (both 
HETH/IAA-CSIC), N. Maicas, and J. L. Lamadrid (both CEFCA) report:

We observed the position of the Fermi GBM/LAT GRB 200219C (Fermi GBM 
team, GCN #27145, Hamburg et al., GCN #27155, Dirirsa et al., GCN 
#27151) with the Javalambre Observatory OAJ 80cm telescope in g'r'i'z', 
obtaining 3 x 300 s exposures in g'r' each, and 5 x 180 s exposures in 
i'z' each. Observations started on 2020-02-21, 03:17:55 UT. No 
observations were obtained the night before as the LAT position came 
only after twilight had started.

In the stacked r' image (midtime 1.14375 days after the GRB), we clearly 
detect a source within the enhanced XRT error circle (Burrows et al., 
GCN #27157) for which we measure r'(AB) = 22.11 Â± 0.13 mag against 
PanSTARRS field stars.

We note this implies a decay compared with the afterglow discovery by 
Reva et al. (GCN #27162) who find R ~ 21.72 Â± 0.15 mag (AB) about six 
hours earlier. It is still brighter than the PanSTARRS host galaxy 
magnitude given by Xu et al. (GCN #27161) at r' = 22.70 Â± 0.15 mag.

The relatively bright host galaxy may be indicative of a low-redshift 
event. As the source is improving in visibility and will be observable 
for several months to come, a search for associated supernova emission 
may be worthwhile. Spectroscopy is encouraged.


GRB_name: GRB200219B
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27167
SUBJECT: IPN triangulation of GRB 200219B (inconsistent with the LIGO/Virgo S200219ac)
DATE:    20/02/22 02:55:08 GMT
FROM:    Anna Ridnaia at Ioffe Institute  <ridnaia@mail.ioffe.ru>

A. Ridnaia, S. Golenetskii, R. Aptekar, D. Frederiks, D. Svinkin,
and T. Cline on behalf of the Konus-Wind team,

K. Hurley, on behalf of the IPN,

A. Goldstein, M. S. Briggs, and C. Wilson-Hodge
on behalf of the Fermi GBM team, and

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, report:

The long-duration GRB 200219B
(Fermi-GBM detection: The Fermi GBM team, GCN 27127)
has been detected by Fermi (GBM trigger  603798859), Konus-Wind,
INTEGRAL (SPI-ACS), so far, at about 35652 s UT (09:54:12).

We have triangulated it to a preliminary, 3 sigma error arc whose
coordinates are:
  ---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
  305.322 (20h 21m 17s) +17.202 (+17d 12' 07")
  Corners:
  303.847 (20h 15m 23s) +18.943 (+18d 56' 35")
  288.913 (19h 15m 39s) -24.952 (-24d 57' 07")
  293.218 (19h 32m 52s) -21.998 (-21d 59' 52")
  306.769 (20h 27m 05s) +15.451 (+15d 27' 04")
  348.097 (23h 12m 23s) +15.820 (+15d 49' 13")
  352.740 (23h 30m 58s) +17.960 (+17d 57' 35")
  ---------------------------------------------
The error arc area is 404.4 sq. deg, and its maximum
dimension is ~81 deg (the minimum one is ~5 deg).
The Sun distance was ~32 deg.

The LIGO/Virgo S200219ac localization (LIGO/Virgo Collaboration,
GCN Circ. 27130) is inconsistent with the arc.

This arc may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB200219_T35651/IPN/

The time history and spectrum will be given in forthcoming GCN Circulars.


GRB_name: GRB200223A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27171
SUBJECT: GRB 200223A: Fermi GBM Final Real-time Localization
DATE:    20/02/23 19:42:25 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 19:32:03 UT on 23 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200223A (trigger 604179128.242596 / 200223814).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 248.4, Dec = -55.8 (J2000 degrees, equivalent to J2000 16h 33m, -55d 47'), with a statistical uncertainty of 7.5 degrees.

The angle from the Fermi LAT boresight is 44.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200223814/quicklook/glg_skymap_all_bn200223814.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200223814/quicklook/glg_healpix_all_bn200223814.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200223814/quicklook/glg_lc_medres34_bn200223814.gif


GRB_name: GRB200224A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27173
SUBJECT: GRB 200224A: Swift detection of a burst
DATE:    20/02/24 03:41:23 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

T. N. Ukwatta (LANL), E. Ambrosi (INAF-IASFPA), A. D'Ai (INAF-IASFPA),
V. D'Elia (SSDC), J. A. Kennea (PSU), N. J. Klingler (PSU),
S. Laha (GSFC/UMBC/CRESST), A. Y. Lien (GSFC/UMBC) and
D. M. Palmer (LANL) report on behalf of the Neil Gehrels Swift
Observatory Team:

At 03:24:49 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 200224A (trigger=958141).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 248.794, +41.675 which is 
   RA(J2000) = 16h 35m 11s
   Dec(J2000) = +41d 40' 31"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a complex
structure with a duration of about 30 sec.  The peak count rate
was ~1000 counts/sec (15-350 keV), at ~3 sec after the trigger. 

The XRT began observing the field at 03:26:26.9 UT, 97.7 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source with an enhanced position: RA, Dec 248.7668, 41.6123 which
is equivalent to:
   RA(J2000)  = 16h 35m 04.04s
   Dec(J2000) = +41d 36' 44.1"
with an uncertainty of 2.9 arcseconds (radius, 90% containment). This
location is 237 arcseconds from the BAT onboard position. This position
may be improved as more data are received; the latest position is
available at https://www.swift.ac.uk/sper.  We cannot determine whether
the source is fading at the present time. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 8.91
x 10^19 cm^-2 (Willingale et al. 2013). 

UVOT results will be reported later. 

Burst Advocate for this burst is T. N. Ukwatta (tilan.ukwatta AT gmail.com). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)

[GCN OPS NOTE(24feb20): This is the second Circular in the sequence of 8 circulars
which were all labeled A because of the sequence assigner being offline.  
This circular was correctly labelled A.]


GRB_name: GRB200224B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27174
SUBJECT: GRB 200224B: Fermi GBM Final Real-time Localization
DATE:    20/02/24 05:16:06 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 05:05:49 UT on 24 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200224A (trigger 604213554.278888 / 200224212).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 177.9, Dec = -28.9 (J2000 degrees, equivalent to J2000 11h 51m, -28d 53'), with a statistical uncertainty of 3.1 degrees.

The angle from the Fermi LAT boresight is 23.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200224212/quicklook/glg_skymap_all_bn200224212.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200224212/quicklook/glg_healpix_all_bn200224212.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200224212/quicklook/glg_lc_medres34_bn200224212.gif

[GCN OPS NOTE(24feb20): This is the third Circular in the sequence of 8 circulars
which were all labeled A because of the sequence assigner being offline.
This circular was orginally, incorrectly labelled A, but the true letter identity is B.]


GRB_name: GRB200224A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27176
SUBJECT: GRB 200224A: BOOTES-1 and 1.5m OSN optical observations
DATE:    20/02/24 06:37:24 GMT
FROM:    Alberto J. Castro-Tirado at IAA-CSIC  <ajct@iaa.es>

A. Sota, E. Fernandez-Garcia, Y.-D. Hu and A. J. Castro-Tirado 
(IAA-CSIC), A. Castellon, I. Carrasco-Garcia and C. Perez del Pulgar 
(UMA), on behalf of a larger collaboration, report:

Following the detection of GRB 200224A by Swift (Ukwatta  et al., GCNC 
27173), the 0.3cm robotic telescope at the BOOTES-1 astronomical station 
at INTA-CEDEA in Huelva (Spain) started gathering images at 03:26:27 UT, 
40s after the alert and 118s after the onset of the burst. No optical 
transient is detected in the single images with a limiting magnitude of 
14 (consistent with the MASTER upper limit, Lipunov et al., GCNC 27172). 
Further data reduction is ongoing.

Deeper exposures were obtained with the 1.5m telescope at Observatorio 
de Sierra Nevada starting at 05:35 UT (i.e. 2.1 h post burst).  We find 
an optical source consistent with the Swift/XRT position,  at 
coordinates (RA & Dec, J2000)  = 16:35:04.11 +41:36:42 (+/- 1â€). The 
preliminary magnitude is R = 22. Further observations are planned to 
confirm whether this is the optical afterglow to GRB 200224A.

This message can be quoted.

[GCN OPS NOTE(24feb20): This is the fifth Circular in the sequence of 8 circulars
which were all labeled A because of the sequence assigner being offline.  
This circular was correctly labelled A.]


GRB_name: GRB200224A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27177
SUBJECT: GRB 200224A: Tautenburg observations
DATE:    20/02/24 07:37:12 GMT
FROM:    Sylvio Klose at TLS Tautenburg  <klose@tls-tautenburg.de>

B. Stecklum, S. Klose, A. Nicuesa Guelbenzu, and S. Melnikov (all 
Tautenburg) report:

We observed the field of GRB 200224A (T0=03:24:49 UT; Ukwatta et al., GCN 
27173) with the Tautenburg 1.34m Schmidt telescope equipped with the 
TAUKAM 6k x 6k CCD camera and the wide V-band filter (VB). The 
transmission curve of this filter closely follows the Gaia GBP filter. 
Observations started at 04:09:53 UT and consisted of 5x3 min exposures.

Based on several Gaia DR2 stars in the field within 1 arcmin radius about 
the afterglow position, we measure for the optical transient (Sota et al., 
GCN 27176) at RA, DEC (J2000) = 16:35:04.11, +41:36:42.4 (+/- 0.5 arcsec) 
the following preliminary Vega magnitude:

mean time t = Feb 24, 04:18:01 UT; t-T0 = 53m 12s;  VB = 21.83 +/- 0.10.


[GCN OPS NOTE(24feb20): This is the sixth Circular in the sequence of 8 circulars
which were all labeled A because of the sequence assigner being offline.  
This circular was correctly labelled A.]


GRB_name: GRB200224C
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27178
SUBJECT: GRB 200224C: Fermi GBM Final Real-time Localization
DATE:    20/02/24 10:09:03 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely SHORT GRB

At 09:58:44 UT on 24 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200224A (trigger 604231129.56693 / 200224416).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 270.5, Dec = -56.8 (J2000 degrees, equivalent to J2000 18h 02m, -56d 47'), with a statistical uncertainty of 6.0 degrees.

The angle from the Fermi LAT boresight is 151.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200224416/quicklook/glg_skymap_all_bn200224416.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200224416/quicklook/glg_healpix_all_bn200224416.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200224416/quicklook/glg_lc_medres34_bn200224416.gif

[GCN OPS NOTE(24feb20): This is the seventh Circular in the sequence of 8 circulars
which were all labeled A because of the sequence assigner being offline.
This circular was orginally, incorrectly labelled A, but the true letter identity is C.]


GRB_name: GRB200224A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27179
SUBJECT: GRB 200224A: Swift-XRT refined Analysis
DATE:    20/02/24 16:21:20 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J. D. Gropp (PSU), J.A. Kennea (PSU), K.L. Page (U. Leicester), A.P.
Beardmore (U. Leicester), T. Sbarrato (INAF-OAB), P. D'Avanzo
(INAF-OAB), M.G. Bernardini (INAF-OAB), A. Tohuvavohu (U. Toronto), 
 and  report on behalf of the Swift-XRT team: report on behalf of the
Swift-XRT team:

We have analysed 12 ks of XRT data for the Swift-detected burst GRB
200224A, from 105 s to 34.0 ks after the  Swift trigger. The data are
entirely in Photon Counting (PC) mode. Using 4055 s of PC mode data and
4 UVOT images, we find an enhanced XRT position (using the XRT-UVOT
alignment and matching UVOT field sources to the USNO-B1 catalogue):
RA, Dec = 248.76655, +41.61133 which is equivalent to:

RA (J2000): 16h 35m 03.97s
Dec(J2000): +41d 36' 40.8"

with an uncertainty of 1.7 arcsec (radius, 90% confidence). This
position is 4.0 arcmin from the Swift position. 

The light curve can be modelled with a power-law decay with a decay
index of alpha=0.86 (+0.10, -0.09).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.09 (+0.39, -0.29). The
best-fitting absorption column is  3.2 (+7.4, -2.3) x 10^20 cm^-2,
consistent with the Galactic value of 8.9 x 10^19 cm^-2 (Willingale et
al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux
conversion factor deduced from this spectrum  is 3.0 x 10^-11 (3.3 x
10^-11) erg cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      3.2 (+7.4, -2.3) x 10^20 cm^-2
Galactic foreground: 8.9 x 10^19 cm^-2
Excess significance: <1.6 sigma
Photon index:      2.09 (+0.39, -0.29)

If the light curve continues to decay with a power-law decay index of
0.86, the count rate at T+24 hours will be 9.9 x 10^-4 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 3.0 x
10^-14 (3.3 x 10^-14) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00958141.

This circular is an official product of the Swift-XRT team.

[GCN OPS NOTE(24feb20): This is the eighth Circular in the sequence of 8 circulars
which were all labeled A because of the sequence assigner being offline.  
This circular was correctly labelled A.]


GRB_name: GRB200219C
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27180
SUBJECT: GRB 200219C: Swift-XRT afterglow confirmation
DATE:    20/02/24 21:22:36 GMT
FROM:    Valerio D'Elia at ASDC  <valerio.delia@ssdc.asi.it>

V. Dâ€™Elia (SSDC) reports on behalf of the Swift-XRT team:

We provide an update on the XRT light curve evolution of the candidate X-ray afterglow of GRB 200219C (GCN Circ. 27157).

The XRT light curve now comprises data up to 260 ks from the Fermi trigger (GCN Circs. 27151 and 27155). There is a firm indication of fading with respect to the first observation, with a decay index of 0.8 (+0.4 -0.3). We thus confirm that this is indeed the afterglow of GRB 200219C.
The latest results can be viewed via: https://www.swift.ac.uk/xrt_curves/00020973/ <https://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.swift.ac.uk%2Fxrt_curves%2F00020973%2F&data=02%7C01%7Cvalerio.delia%40ssdc.asi.it%7Ccbb05988e1604c1b0a9608d7b9502580%7Ccbfc58d4e60f468d8fe490676de085f7%7C0%7C0%7C637181626207379817&sdata=y0NsJNyq79oZqD4RZJb5be%2Fwwkz6UNNz%2B%2F3wajd%2Bs54%3D&reserved=0>

This circular is an official product of the Swift-XRT team.


GRB_name: GRB200224B
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27181
SUBJECT: Correction in name: GRB 200224B and GRB 200224C (not GRB 200224A)
DATE:    20/02/24 21:32:30 GMT
FROM:    Stephen Lesage at Fermi-GBM Team  <sjl0014@uah.edu>

S. Lesage (UAH) reports on behalf of the Fermi GBM Team:

â€œThe Fermi Gamma-ray Burst Monitor (GBM) triggers 604213554/200224212
at 05:05:49 UT and 604231129/200224416 at 09:58:44 on 24 Feb 2020,
originally named GRB 200224A in GCN 27174 and GCN 27178, should be
GRB 200224B and GRB 200224C respectively.
We apologize for any confusion caused."


GRB_name: GRB200224A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27182
SUBJECT: GRB 200224A: Swift/UVOT Detection
DATE:    20/02/24 21:40:15 GMT
FROM:    Frank Marshall at Swift/UVOT  <marshall@milkyway.gsfc.nasa.gov>

F. E. Marshall (NASA/GSFC) and T. N. Ukwatta (LANL)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 200224A
101 s after the BAT trigger (Ukwatta et al., GCN Circ. 27173).
A source consistent with the enhanced XRT position
(Gropp et al., GCNC 27179) and the optical positions reported
by Sota et al. (GCNC 27176) and Stecklum et al. (GCNC 27177)
is detected in the initial UVOT exposures.
The source is very close to the edge of the image in the
first exposure at 101 s after the BAT trigger, and further
analysis is required to determine an accurate intensity
for that exposure.

The preliminary UVOT position is:
    RA  (J2000) =  16:35:04.14 = 248.76727 (deg.)
    Dec (J2000) = +41:36:42.3  =  41.61174 (deg.)
with an estimated uncertainty of 0.43 arc sec. (radius, 90% confidence).

Preliminary detections and 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)           Mag

u                  259          509          246         18.75 +/- 0.10
white              861         1011          147         20.57 +/- 0.20
w1                5978        19265         1098        >20.7
m2                5772        18542         1279        >21.4
w2                5363        30092         1953        >21.9

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.005 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB200224C
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27183
SUBJECT: IPN triangulation of GRB 200224C
DATE:    20/02/24 21:54:15 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

D. Svinkin and K. Hurley, on behalf of the IPN,

A. Goldstein, M. S. Briggs, and C. Wilson-Hodge
on behalf of the Fermi GBM team, and

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,
report:

The short-duration GRB 200224C (The Fermi GBM team, GCN Circ. 27178)
has been detected by Fermi (GBM trigger 604231129) and
INTEGRAL (SPI-ACS), so far, at about 35925 s UT (09:58:45).

We have triangulated this GRB to a GBM-INTEGRAL annulus centered at
RA(2000)=205.247 deg (13h 40m 59s) Dec(2000)=+54.669 deg (+54d 40' 10"),
whose radius is 82.665 +/- 2.948 deg (3 sigma).

The IPN localization is consistent with, but reduces the area of, the
Fermi GBM one.

This localization may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB200224_T35924/IPN/


GRB_name: GRB200224A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27189
SUBJECT: GRB 200224A: RATIR Optical Observations and Confirmation of the Afterglow
DATE:    20/02/25 00:49:46 GMT
FROM:    Rosa Leticia Becerra Godinez at Inst. de Astronoma,UNAM  <rbecerra@astro.unam.mx>

Rosa L. Becerra (UNAM), Margarita Pereyra (UNAM), Alan M. Watson (UNAM),
 Nat Butler (ASU), Alexander Kutyrev (GSFC), William H. Lee (UNAM),
Michael G. Richer (UNAM), Ori Fox (STScI), J. Xavier Prochaska (UCSC),
Josh Bloom (UCB), Antonino Cucchiara (UVI), Eleonora Troja (GSFC),
Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), JesÃºs GonzÃ¡lez (UNAM),
Carlos RomÃ¡n-ZÃºÃ±iga (UNAM), Harvey Moseley (GSFC), John Capone (UMD),
V. Zach Golkhou (U. Wash.), and Vicki Toy (UMD) report:

We observed the field of GRB 200224A (Palmer D., et al., GCN 27173) with the
Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the
1.5m Harold Johnson Telescope at the Observatorio AstronÃ³mico Nacional on
Sierra San Pedro MÃ¡rtir from 2020/02 24.36 to 2020/02 24.54 UTC (5.33
to 9.66 hours after the BAT trigger), obtaining a total of 3.44 hours
exposure in the r and i bands.

For a source within the Swift-XRT error circle, in comparison with the SDSS
DR9 and 2MASS catalogs, we obtain the following upper limits (3-sigma):

  r > 23.88
  i > 23.84

These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.

Castro-Tirado et al. (GCN 27176)
and Stecklum et al. (GCN 27177) report an afterglow candidate at roughly
magnitude 22 at about 1 and 2 hours after the burst. Our observations show
subsequent fading of this source and confirm that it is the afterglow.

We thank the staff of the Observatorio AstronÃ³mico Nacional in San Pedro
MÃ¡rtir.


GRB_name: GRB200224A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27191
SUBJECT: GRB 200224A: LCO Upper Limits
DATE:    20/02/25 04:02:07 GMT
FROM:    Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh@uvi.edu>

R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (U. of the Virgin Islands/College of Marin) report on behalf of a larger collaboration:

We observed Swift GRB 200224A (Ukwatta et al., GCN 27173) with the LCO 1-m Sinistro instrument at the McDonald Observatory, Texas, USA site, on February 24, from 12:01 to 12:18 UT (corresponding to 8.62 to 8.90 hours from the GRB trigger time) with the Bessel I and R filters.

We performed a series of 5x120s exposures in I and 3x120s in R. We do not detect any sources in the individual frames (nor in stacked images) in the Swift error region.  Using the USNO-B.1 catalog as reference, we obtain the following 3-sigma upper limits:

R > 19.85

I > 19.05

R.S. is funded by NSF AST grant #1831682


GRB_name: GRB200224A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27194
SUBJECT: GRB 200224A: Swift-BAT refined analysis
DATE:    20/02/25 06:53:49 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

A. Y. Lien (GSFC/UMBC), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), H. A. Krimm (NSF),
S. Laha (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU), T. N. Ukwatta (LANL)
(i.e. the Swift-BAT team):

Using the data set from T-240 to T+962 sec from the recent telemetry
downlink,
we report further analysis of BAT GRB 200224A (trigger #958141)
(Ukwatta et al., GCN Circ. 27173).  The BAT ground-calculated position is
RA, Dec = 248.743, 41.666 deg which is
   RA(J2000)  =  16h 34m 58.4s
   Dec(J2000) = +41d 39' 57.2"
with an uncertainty of 3.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 100%.

The mask-weighted light curve shows a weak pulse from ~T0 to ~T+5 s,
followed
by some weaker emission that lasts till ~T+50 s. T90 (15-350 keV)
is 45.0 +- 9.2 sec (estimated error including systematics).

The time-averaged spectrum from T-0.79 to T+49.21 sec is best fit by a
simple
power-law model.  The power law index of the time-averaged spectrum is
1.69 +- 0.51.  The fluence in the 15-150 keV band is 2.9 +- 0.9 x 10^-7
erg/cm2.
The 1-sec peak photon flux measured from T+2.21 sec in the 15-150 keV band
is 0.4 +- 0.1 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/958141/BA/


GRB_name: GRB200221A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27210
SUBJECT: IPN triangulation of GRB 200221A (short)
DATE:    20/02/25 19:00:47 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, A. Ridnaia,
and T. Cline on behalf of the Konus-Wind team,

K. Hurley, on behalf of the IPN,

A. Goldstein, M. S. Briggs, and C. Wilson-Hodge
on behalf of the Fermi GBM team,

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, and

S. Xiao, C. K. Li, X. B. Li, Y. Huang, and S. L. Xiong
on behalf of the Insight-HXMT GRB team, report:

The short-duration GRB 200221A (The Fermi GBM team, GCN Circ. 27159)
was detected by Fermi (GBM trigger 603949983), Konus-Wind,
INTEGRAL (SPI-ACS), and Insight (HXMT/HE)
at about 13979 s UT (03:52:59).

We have triangulated it to a preliminary, 3 sigma error box
whose coordinates are:
  --------------------------------
   RA(2000), deg   Dec(2000), deg
  --------------------------------
  Center:
    178.682        +33.400
  Corners:
    182.119        +35.008
    132.491        +48.390
    141.935        +43.606
    175.374        +31.702
    179.446         +3.183
    183.926         -3.580
  ---------------------------------
The error box area is 455 sq. deg, and its maximum
dimension is 68.5 deg (the minimum one is 6.5 deg).
The Sun distance was ~140 deg.

The IPN localization is consistent with, but reduces the area of, the 
Fermi-GBM one.

This box may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB200221_T13983/IPN

The Konus-Wind time history and spectrum will be given in a forthcoming
GCN Circular.


GRB_name: GRB200224B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27215
SUBJECT: GRB 200224B: DDOTI/OAN optical observations report
DATE:    20/02/26 00:30:12 GMT
FROM:    Emma Margarita Pereyra Talamantes at IA-UNAM Ensenada  <mpereyra@astro.unam.mx>

Margarita Pereyra (UNAM), Nat Butler (ASU), Alan M. Watson (UNAM),
Eleonora Troja (GSFC/UMD), Simone Dichiara (GSFC/UMD), Rosa L. Becerra
(UNAM), William H. Lee (UNAM), Diego Gonzalez (UNAM), Alexander Kutyrev
(GSFC/UMD), and Tanner Wolfram (ASU), report:

We observed the field of GRB 200224B detected by the Fermi Gamma-ray Burst
Monitor (GCN 27174, Fermi trigger 604213554), with the DDOTI/OAN wide-field
imager at the Observatorio AstronÃ³mico Nacional on Sierra San Pedro MÃ¡rtir (
http://ddoti.astroscu.unam.mx) from 2020-02-24 06:47 to 2020-02-24 12:16
UTC (1.68 to 7.16 hours after the event).

We observed a region of 13.6 degrees in RA by 20.4 degrees in declination,
with a 2 x 2 grid, centered on the Fermi GBM Final Position +11:51:36
-28:52:11 J2000. This region contains about 277 square degrees. We obtained
2040 to 2520 seconds exposure across the region. We calibrated our images
against the APASS catalog. Our 10-sigma limiting magnitude is around w =
19.45.

Comparing to the USNO-B1, DSS DR2 and Pan-STARRS DR1 catalogs, we do not
detect any uncataloged source with significant fading within the 90%
probability radius of 6.3 degrees.

We thank the staff of the Observatorio AstronÃ³mico Nacional in San Pedro
MÃ¡rtir.


-- 
*Dr. Margarita Pereyra *

*FFTF, Schlumberger Foundation Alumnae*
----------------------------------------------------------------------------------------------------------------

*CatedrÃ¡tico Conacyt*

*Instituto de AstronomÃ­a de la UNAM,*

*Km. 107 Carretera Tijua**na-Ensenada, *

*Ensenada Baja California, MÃ©xico. C.P. 22860*

Oficina: 405

Skype: margarita-pereyra


GRB_name: GRB200219A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27218
SUBJECT: GRB 200219A: Chandra rapid ToO upper limit
DATE:    20/02/26 06:32:01 GMT
FROM:    Takanori Sakamoto at AGU  <tsakamoto@phys.aoyama.ac.jp>

T. Sakamoto (AGU), E. Troja (NASA/GSFC/ORAU), J. Norris (BSU),
S. D. Barthelmy (GSFC), J. L. Racusin (GSFC), N. Kawai (Tokyo Tech),
A. Fruchter (STScI), M. Im (SNU)

A Chandra ToO observation of GRB 200219A (Lien et al., GCN Circ. 27125;
Bissaldi et al., GCN Circ. 27137) started on February 23 16:32 UT (~4.4 days
after the GRB trigger) for a total of 19.2 ksec.

We do not detect an X-ray afterglow at the location of the enhanced XRT position
(Osborne et al., GCN Circ. 27138).  The calculated 3-sigma upper limit is 3.3e-4 c/s
in the 0.35-8 keV band using aprates of the CIAO software package.
Using the best fit spectral parameters of the XRT PC mode data, we estimated
an 3-sigma unabsorbed flux upper limit of 5.0e-15 erg/cm2/s in the 0.35-8 keV band.

We would like to thank the Chandra operation team for rapidly approving and
making this observation.


GRB_name: GRB200224A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27222
SUBJECT: GRB 200224A: Calar Alto 2.2m optical afterglow detection
DATE:    20/02/26 10:47:39 GMT
FROM:    Alexander Kann at IAA-CSIC  <kann@iaa.es>

J. F. Agui Fernandez, M. Blazek, D. A. Kann (all HETH/IAA-CSIC), A. de 
Ugarte Postigo (HETH/IAA-CSIC, DARK/NBI), C. C. Thoene (HETH/IAA-CSIC), 
E. Gallego-Cano, and A. Guijarro (both CAHA) report:

We observed the field of the Swift-detected GRB 200224A (Ukwatta et al., 
GCN #21173) with the 2.2m telescope at CAHA, Almeria, Spain. We obtained 
5 x 120 s each in Rc and Ic.

At the position of the optical afterglow reported by Sota et al. (GCN 
#27176), Stecklum et al. (GCN #21177), and Marshall & Ukwatta (GCN 
#27182), we clearly detect a source in each stack image.

We measure Rc = 21.60 +/- 0.06 mag at 0.03702 days after the GRB, and Ic 
= 21.31 +/- 0.09 mag at 0.05794 days after the GRB (Vega magnitudes), in 
good agreement with the measurements of Tautenburg at an earlier time 
(GCN #27177) and OSN at a later time (GCN #27176).

We note the optical afterglow is very faint (see also Becerra et al., 
GCN #27189), but the clear detection in u by Swift/UVOT (GCN #27182) as 
well as the blue Rc-Ic color we find indicates this GRB is neither at 
high redshift nor particularly extinguished (see also the XRT results, 
Gropp et al., GCN #27179), it is likely just intrinsically faint.


GRB_name: GRB200219A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27226
SUBJECT: Konus-Wind observation of GRB 200219A
DATE:    20/02/26 16:09:54 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks,
M. Ulanov, A. Tsvetkova, A. Lysenko, A. Ridnaia, and T. Cline
on behalf of the Konus-Wind team, report:

The short-duration GRB 200219A
(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 27123;
Bissaldi and Meegan, GCN Circ. 27137;
Swift-BAT detection: Lien et al., GCN Circ. 27125;
Laha et al., GCN Circ. 27148)
triggered Konus-Wind at T0=27405.513 s UT (07:36:45.513).

The burst light curve shows a single multi-peaked pulse
which starts at ~T0-0.2 s and has a total duration of ~0.4 s.
The emission is seen up to ~8 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB200219_T27405/

As observed by Konus-Wind, the burst
had a fluence of 4.12(-0.61,+0.67)x10^-6 erg/cm2,
and a 16-ms peak flux, measured from T0+0.182 s,
of 2.34(-0.73,+0.76)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum of the burst
(measured from T0 to T0+0.256 s)
is best fit in the 20 keV - 8 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with  alpha = -0.06(-0.28,+0.35)
and Ep = 952(-173,+218) keV (chi2 = 29/27 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2.6
(chi2 = 29/26 dof).

All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.


GRB_name: GRB200219C
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27228
SUBJECT: Konus-Wind observation of GRB 200219C
DATE:    20/02/26 19:03:50 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks,
M. Ulanov, A. Tsvetkova, A. Lysenko, A. Ridnaia, and T. Cline
on behalf of the Konus-Wind team, report:

The long-duration GRB 200219C
(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 27145;
Hamburg et al., GCN Circ. 27155;
Fermi-LAT detection: Dirirsa et al., GCN Circ. 27151;
CALET-GBM detection: Sugita et al., GCN Circ. 27163)
triggered Konus-Wind at T0=86229.162 s UT (23:57:09.162).

The burst light curve shows a bright peak which starts at ~T0-3.4 s
and has a duration of ~9.8 s, followed by a weaker emission
seen up to ~T0+23 s. Total burst duration is ~27 s.
The emission is seen up to ~4 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB200219_T86229

As observed by Konus-Wind, the burst
had a fluence of 1.87(-0.11,+0.13)x10^-5 erg/cm2,
and a 64-ms peak flux, measured from T0+3.488 s,
of 5.40(-1.08,+1.23)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum of the burst
(measured from T0 to T0+29.952 s)
is best fit in the 20 keV - 2 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with  alpha = -1.08(-0.12,+0.12)
and Ep = 209(-21,+27) keV (chi2 = 60/61 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2.6
(chi2 = 60/60 dof).

The spectrum near the maximum count rate
(measured from T0+0.256 to T0+5.376 s)
is best fit in the 20 keV - 4 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.83(-0.10,+0.12),
the high energy photon index beta = -3.58(-6.42,+0.82),
the peak energy Ep = 234(-22,+20) keV
(chi2 = 62/75 dof).

All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.


GRB_name: GRB200227A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27233
SUBJECT: GRB 200227A: Fermi GBM Final Real-time Localization
DATE:    20/02/27 07:30:29 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 07:20:08 UT on 27 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200227A (trigger 604480813.702942 / 200227306).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 56.9, Dec = 6.3 (J2000 degrees, equivalent to J2000 03h 47m, 6d 17'), with a statistical uncertainty of 1.0 degrees.

The angle from the Fermi LAT boresight is 19.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200227306/quicklook/glg_skymap_all_bn200227306.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200227306/quicklook/glg_healpix_all_bn200227306.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200227306/quicklook/glg_lc_medres34_bn200227306.gif


GRB_name: GRB200227A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27234
SUBJECT: GRB 200227A: Swift detection of a burst
DATE:    20/02/27 07:37:50 GMT
FROM:    Sibasish Laha at GSFC  <sib.laha@gmail.com>

S. Laha (GSFC/UMBC/CRESST), C. Gronwall (PSU), N. J. Klingler (PSU),
A. Y. Lien (GSFC/UMBC), K. L. Page (U Leicester) and
A. Tohuvavohu (U Toronto) report on behalf of the Neil Gehrels Swift
Observatory Team:

At 07:20:08 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 200227A (trigger=958592).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 56.436, +9.491 which is 
   RA(J2000) = 03h 45m 45s
   Dec(J2000) = +09d 29' 27"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a complex
structure with a duration of about 40 sec.  The peak count rate
was ~4500 counts/sec (15-350 keV), at ~8 sec after the trigger. 

The XRT began observing the field at 07:21:30.1 UT, 82.2 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
uncatalogued X-ray source located at RA, Dec 56.43302, 9.48264 which is
equivalent to:
   RA(J2000)  = 03h 45m 43.92s
   Dec(J2000) = +09d 28' 57.5"
with an uncertainty of 3.5 arcseconds (radius, 90% containment). This
location is 31 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at https://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 2.12
x 10^21 cm^-2 (Willingale et al. 2013). 

The initial flux in the 2.5 s image was 3.08e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 93 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of
the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. 
The 8'x8' region for the list of sources generated on-board covers 100% of the
XRT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.27. 

Burst Advocate for this burst is S. Laha (sib.laha AT gmail.com). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB200227A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27236
SUBJECT: GRB 200227A: MITSuME Akeno optical upper limit
DATE:    20/02/27 11:59:48 GMT
FROM:    Motoki Oeda at Tokyo Inst. of Tech.  <oeda@hp.phys.titech.ac.jp>

M. Oeda, R. Adachi, K. L. Murata, K. Shiraishi, K. Iida, M. Niwano, F.
Ogawa, S. Toma, R. Hosokawa, N. Nakamura, Y. Yatsu, and N.
Kawai(TokyoTech) report on behalf of the MITSuME collaboration:

We searched for the optical counterpart of GRB 200227A (Fermi GBM Team
et al.,GCN Circular #27233, S. Laha et al., GCN Circular #27234) with
the optical three color (gâ€™, Rc, and Ic) CCD cameras attached to the
MITSuME 50 cm telescope of Akeno Observatory, Yamanashi, Japan.
The observation started on 09:05:08 UT. We did not find any new point
sources within the Swift/XRT circle (S. Laha et al., GCN Circular
#27234) in all three bands.
We obtained the 5-sigma limits as follows.

T0+[hour] MID-UT T-EXP[sec] 5-sigma limits
------------------------------------------------------------------------------------------------
2.2   09:41:13  900  gâ€™>18.4,Rc>18.2,Ic>17.5
------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time

We used UCAC4 catalog for flux calibration.
The magnitudes are expressed in the AB system.
The images were processed in real-time through the MITSuME GPU
reduction pipeline (Niwano et al. ,in prep;
https://github.com/MNiwano/Eclair)


GRB_name: GRB200227A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27239
SUBJECT: GRB 200227A: Fermi GBM observation
DATE:    20/02/27 14:19:53 GMT
FROM:    Elisabetta Bissaldi at INFN,Bari  <elisabetta.bissaldi@ba.infn.it>

E. Bissaldi (Politecnico and INFN Bari)
reports on behalf of the Fermi GBM Team:


"At 07:20:08.70 UT on 27 February 2020, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 200227A (trigger 604480813 / 200227306),
which was also detected by the Swift/BAT (Laha et al. 2020, GCN 27234).
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 19 degrees.

The GBM light curve shows a single broad peak
with a duration (T90) of about 24 s (50-300 keV).
The time-averaged spectrum from T0 to T0+24 s is
adequately fit by a Band function with
Epeak = 139 +/- 10 keV, alpha = -0.95 +/- 0.05,
and beta = -2.28 +/- 0.11.

The event fluence (10-1000 keV) in this time interval is
(1.41  +/- 0.04)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+7.1 s in the 10-1000 keV band
is 8.8 +/- 0.4 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB200224A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27240
SUBJECT: GRB 200224A: Mondy optical upper limit
DATE:    20/02/27 16:28:46 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

S. Belkin (IKI), A. Pozanenko (IKI), E. Klunko (ISTP), E. Mazaeva (IKI), 
A. Volnova (IKI) report on behalf of IKI-GRB-FuN:

We observed the field of GRB 200224A (Ukwatta  et al., GCN 27173; Fermi 
GBM team GCN 27174) with AZT-33IK telescope of Sayan observatory (Mondy) 
starting on Feb. 26 (UT) 17:24:49. We did not detect the optical 
afterglow (Sota et al., GCN 27176; Stecklum et al., GCN 27177; Marshall 
et al., GCN 27182; Becerra et al., GCN 27182; Fernandez et al., GCN 
27222). Preliminary photometry of the field is following.

Date UT start,      t-T0    Filter Exp.   OT UL(3sigma)
                     (mid, days)    (s)
2020-02-26 17:24:49 2.60348 R      29*120 n/d 22.6

Photometry is based on the USNO-B1.0 nearby stars.


GRB_name: GRB200227A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27243
SUBJECT: GRB 200227A: Enhanced Swift-XRT position
DATE:    20/02/27 19:23:57 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 702 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 200227A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 56.43275, +9.48230 which is equivalent
to:

RA (J2000): 03h 45m 43.86s
Dec (J2000): +09d 28' 56.3"

with an uncertainty of 2.5 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB200227A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27244
SUBJECT: GRB 200227A: Swift/UVOT Upper Limits
DATE:    20/02/27 21:16:21 GMT
FROM:    Samantha Oates at MSSL  <samantha.oates@alumni.ucl.ac.uk>

S. R. Oates (U. Birmingham) and S. Laha (GSFC/UMBC/CRESST)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 200227A
93 s after the BAT trigger (Laha et al., GCN Circ. 27234).
No optical afterglow consistent with the XRT position
(Beardmore et al. GCN Circ. 27243)
is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)     Mag

white_FC          93          243          147        >20.3
u_FC              305       555          246        >19.7
white           93       1185         353        >20.8
v           634       1235         78         >18.3
b           560       1160         58         >19.2
u                 305       1135         285        >19.8
w1                685       1284         58         >18.4
m2                659         1259         78         >18.4
w2                610         1210         78         >18.6

The magnitudes in the table are not corrected for the Galactic extinction
due to the significant reddening of E(B-V) = 0.28 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB200219A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27245
SUBJECT: GRB 200219A: ATCA 5/9 GHz radio observations
DATE:    20/02/28 03:46:19 GMT
FROM:    Gemma Anderson at Curtin U  <gemma.anderson@curtin.edu.au>

D. dâ€™Antonio (UTS), M. E. Bell (UTS), G. E. Anderson (Curtin), J. Stevens
(CASS), P. J. Hancock (Curtin), J. C. A. Miller-Jones (Curtin), M. D. Aksulu
(UvA), A. Bahramian (Curtin), K. W. Bannister (CASS), A. J, van der Horst
(GWU), S. D. Ryder (Macquarie), J-P. Macquart (Curtin), R. M. Plotkin
(UNR), A. Rowlinson (UvA), R. A. M. J. Wijers (UvA)

We used the Australia Telescope Compact Array (ATCA) to perform a radio
observation of the short GRB 200219A. The scheduled observations began on
2020 Feb 22.8 UT for 7.5 hours (3.5 days post-burst; Fermi GBM Team GCN
27123, A. Y. Lien et al., GCN 27125). No radio source was detected at the XRT
position (J.P. Osborne et al., GCN 27138), with preliminary 3 sigma upper-limits
of 53 microJy and 57 microJy at 5.5 and 9 GHz, respectively.

We thank the ATCA and CSIRO Astronomy and Space Science (CASS) staff for
scheduling these observations.


GRB_name: GRB200227A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27246
SUBJECT: GRB 200227A: Swift-BAT refined analysis
DATE:    20/02/28 05:04:40 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>

J. R. Cummings (CPI), S. D. Barthelmy (GSFC), H. A. Krimm (NSF),
S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU), T. N. Ukwatta (LANL)
(i.e. the Swift-BAT team):
 
Using the data set from T-61 to T+243 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 200227A (trigger #958592)
(Laha, et al., GCN Circ. 27234).  The BAT ground-calculated position is
RA, Dec = 56.433, 9.489 deg, which is 
   RA(J2000)  =  03h 45m 43.9s 
   Dec(J2000) = +09d 29' 22.0" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 46%.
 
The mask-weighted light curve a couple overlapping peaks starting
at T-10 sec, peaking at T+8 sec, and ending at T+90 sec.
T90 (15-350 keV) is 32.8 +- 9.7 sec (estimated error including systematics).
 
The time-averaged spectrum from T-0.50 to T+87.64 sec is best fit by a power law
with an exponential cutoff.  This fit gives a photon index 1.15 +- 0.19, 
and Epeak of 156.4 +- 88.9 keV (chi squared 55.3 for 56 d.o.f.).  For this
model the total fluence in the 15-150 keV band is 7.1 +- 0.2 x 10^-6 erg/cm2
and the 1-sec peak flux measured from T+8.54 sec in the 15-150 keV band is
5.7 +- 0.4 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 1.46 +- 0.05 (chi squared 63.6 for 57 d.o.f.).  All the quoted errors
are at the 90% confidence level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/958592/BA/


GRB_name: GRB200228A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27247
SUBJECT: GRB 200228A: Fermi GBM Final Real-time Localization
DATE:    20/02/28 07:08:54 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 06:58:33 UT on 28 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200228A (trigger 604565918.806272 / 200228291).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 328.0, Dec = -46.5 (J2000 degrees, equivalent to J2000 21h 52m, -46d 30'), with a statistical uncertainty of 1.5 degrees.

The angle from the Fermi LAT boresight is 33.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200228291/quicklook/glg_skymap_all_bn200228291.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200228291/quicklook/glg_healpix_all_bn200228291.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200228291/quicklook/glg_lc_medres34_bn200228291.gif


GRB_name: GRB200228A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27248
SUBJECT: GRB 200228A: BALROG localization (Fermi Trigger 604565918 / GRB 200228291)
DATE:    20/02/28 07:24:28 GMT
FROM:    Jochen Greiner at MPE,Garching  <jcg@mpe.mpg.de>

F. Kunzweiler, B. Biltzinger, F. Berlato, J. Burgess & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
604565918 at 06:58:33 on 28 Feb. 2020 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).

The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 332.9+/-0.9 deg
Decl.(2000.0) = -39.9+/-1.0 deg
We estimate an additional systematic error of 1 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB200228291/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB200228291/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB200228291/json

                        


GRB_name: GRB200227A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27249
SUBJECT: GRB 200227A: Swift-XRT refined Analysis
DATE:    20/02/28 07:49:20 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J.A. Kennea (PSU), A.P. Beardmore (U. Leicester), J.P. Osborne (U.
Leicester), P. D'Avanzo (INAF-OAB), M.G. Bernardini (INAF-OAB), E.
Ambrosi  (INAF-IASFPA) , A. Tohuvavohu (U. Toronto), B. Sbarufatti
(PSU) and S. Laha (GSFC/UMBC/CRESST) report on behalf of the Swift-XRT
team:

We have analysed 6.1 ks of XRT data for GRB 200227A (Laha et al. GCN
Circ. 27234), from 72 s to 29.1 ks after the  BAT trigger. The data
comprise 288 s in Windowed Timing (WT) mode (the first 8 s were taken
while Swift was slewing) with the remainder in Photon Counting (PC)
mode. The enhanced XRT position for this burst was given by Beardmore
et al. (GCN Circ. 27243).

The light curve can be modelled with an initial power-law decay with an
index of alpha=3.86 (+0.21, -0.16), followed by a break at T+169 s to
an alpha of 1.09 (+0.07, -0.05).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.88 (+0.08, -0.07). The
best-fitting absorption column is  5.9 (+/-0.5) x 10^21 cm^-2, in
excess of the Galactic value of 2.1 x 10^21 cm^-2 (Willingale et al.
2013). The PC mode spectrum has a photon index of 1.83 (+0.17, -0.16)
and a best-fitting absorption column of 5.6 (+1.1, -1.0) x 10^21 cm^-2.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum  is 4.6 x 10^-11 (6.9 x 10^-11) erg cm^-2
count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      5.6 (+1.1, -1.0) x 10^21 cm^-2
Galactic foreground: 2.1 x 10^21 cm^-2
Excess significance: 5.7 sigma
Photon index:      1.83 (+0.17, -0.16)

If the light curve continues to decay with a power-law decay index of
1.09, the count rate at T+24 hours will be 4.8 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.2 x
10^-13 (3.3 x 10^-13) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00958592.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB200227A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27251
SUBJECT: GRB 200227A: Insight-HXMT/HE detection
DATE:    20/02/28 08:57:43 GMT
FROM:    Qi Luo at IHEP  <luoqi@ihep.ac.cn>

Q. Luo, Y. G. Zheng, C. Cai, S. Xiao, Q. B. Yi, Y. F. DU, W. C. Xue, 
Y. Huang, C. K. Li, G. Li, X. B. Li, J. Y. Liao, S. L. Xiong,
C. Z. Liu, X. F. Li, Z. W. Li, Z. Chang, A. M. Zhang, 
Y. F. Zhang, X. F. Lu, C. L. Zou (IHEP), Y. J. Jin, 
Z. Zhang (THU), T. P. Li (IHEP/THU), F. J. Lu, L. M. Song, 
M. Wu, Y. P. Xu, S. N. Zhang (IHEP), 
report on behalf of the Insight-HXMT team:

At 2020-02-27T07:20:16.15 (T0), Insight-HXMT/HE detected 
GRB 200227A (trigger ID: HEB200227305) in a routine search of the data, 
which was also detected by Fermi/GBM (GCN #27233) and Swift-BAT 
(GCN #27234).

The Insight-HXMT/HE light curve mainly consists of two 
pulses with a duration (T90) of 37.71 s measured from T0-6.92 s. 
The 1-ms peak rate, measured from T0+1.169 s, is 1862 cnts/sec. 
The total counts from this burst is 19259 counts.
URL_LC: http://www.hxmt.org/images/GRB/HEB200227305_lc.jpg 

All measurements above are made with the CsI detectors operating in the 
regular mode with the energy range of about 80-800 keV (deposited energy). 
Only gamma-rays with energy greater than about 200 keV can penetrate 
the spacecraft and leave signals in the CsI detectors installed inside 
of the telescope. 

Insight-HXMT is the first Chinese space X-ray telescope, which was 
funded jointly by the China National Space Administration (CNSA) and 
the Chinese Academy of Sciences (CAS). 
More information about it could be found at: 
http://www.hxmt.org.


GRB_name: GRB200228B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27253
SUBJECT: GRB 200228B: Fermi GBM Final Real-time Localization
DATE:    20/02/28 11:25:00 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 11:14:43 UT on 28 Feb 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200228B (trigger 604581288.894278 / 200228469).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 258.4, Dec = 9.6 (J2000 degrees, equivalent to J2000 17h 13m, 9d 35'), with a statistical uncertainty of 16.7 degrees.

The angle from the Fermi LAT boresight is 62.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200228469/quicklook/glg_skymap_all_bn200228469.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200228469/quicklook/glg_healpix_all_bn200228469.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200228469/quicklook/glg_lc_medres34_bn200228469.gif


GRB_name: GRB200228B
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27254
SUBJECT: GRB 200228B: Swift detection of a burst
DATE:    20/02/28 11:27:30 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>

S. Laha (GSFC/UMBC/CRESST), S. D. Barthelmy (GSFC),
P. A. Evans (U Leicester), C. Gronwall (PSU), J.D. Gropp (PSU) and
K. L. Page (U Leicester) report on behalf of the Neil Gehrels Swift
Observatory Team:

At 11:14:41 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 200228B (trigger=958733).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 252.026, +16.960, which is 
   RA(J2000)  =  16h 48m 06s
   Dec(J2000) = +16d 57' 37"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows a single peak
with a duration of about 25 sec.  The peak count rate
was ~2000 counts/sec (15-350 keV), at ~5 sec after the trigger. 

The XRT began observing the field at 11:16:56.8 UT, 135.7 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source located at RA, Dec 252.04730, 16.98505 which is equivalent
to:
   RA(J2000)  = 16h 48m 11.35s
   Dec(J2000) = +16d 59' 06.2"
with an uncertainty of 5.7 arcseconds (radius, 90% containment). This
location is 116 arcseconds from the BAT onboard position, within the
BAT error circle. This position may be improved as more data are
received; the latest position is available at
https://www.swift.ac.uk/sper. No spectrum from the promptly downlinked
event data is yet available to determine the column density. 

UVOT data are unavailable at this time. 

Burst Advocate for this burst is S. Laha (sib.laha AT gmail.com). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB200228B
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27256
SUBJECT: GRB 200228B: Enhanced Swift-XRT position
DATE:    20/02/28 14:16:49 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 87 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 200228B, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 252.04640, +16.98523 which is equivalent
to:

RA (J2000): 16h 48m 11.14s
Dec (J2000): +16d 59' 06.8"

with an uncertainty of 3.5 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB200227A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27257
SUBJECT: GRB 200227A: Mondy optical upper limit
DATE:    20/02/28 14:30:50 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

S. Belkin (IKI), A. Pozanenko (IKI), E. Klunko (ISTP), E. Mazaeva (IKI), 
A. Volnova (IKI) report on behalf of IKI-GRB-FuN:

We observed the field of GRB 200227A (Fermi GBM Team et al., GCN 27233; 
Laha et al., GCN 27234) with AZT-33IK telescope of Sayan observatory 
(Mondy) starting on Feb. 27 (UT) 12:47:07.  Within enhanced Swift-XRT 
position of afterglow (Beardmore et al., GCN 27243) we did not detect 
optical
  afterglow in agreement with previously reported non-detection (Oeda et 
al., GCN 27236;  Oates et al., GCN 27244). Preliminary photometry of the 
field is following.

Date UT start,      t-T0    Filter Exp.   OT UL(3sigma)
                      (mid, days)    (s)
2020-02-27 12:47:07 0.24582  R   27*120 n/d 23.2

Photometry is based on the SDSS-DR12 nearby stars (Luptonâ€™s transformation)
SDSS-DR12_id        R(Lupton)
J034542.04+092727.3 18.56
J034546.87+092955.7 17.19
J034534.13+092646.2 17.32


GRB_name: GRB200228A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27259
SUBJECT: GRB 200228A: Swift/BAT detection and arcminute localization from GUANO
DATE:    20/02/28 14:53:21 GMT
FROM:    Aaron Tohuvavohu at U Toronto  <aaron.tohu@gmail.com>

Aaron Tohuvavohu (U Toronto), James DeLaunay (PSU), and Jamie Kennea
(PSU) report:

Swift/BAT did not trigger on GRB 200228A, likely due to a slew.

The Fermi/GBM Flight-Position notice, distributed at T0+23 seconds,
from the Fermi/GBM detected GRB 200228A (GCN. 27247) triggered the
Swift Mission Operations Center operated Gamma-ray Urgent Archiver for
Novel Opportunities (GUANO; Tohuvavohu et al. 2020, in prep).

The GUANO is a fully autonomous, extremely low latency, spacecraft
commanding pipeline designed for targeted recovery of BAT event mode
data around the times of compelling astrophysical events to enable
more sensitive GRB searches.

Upon trigger by the Fermi notice, GUANO sent a command to the Swift
Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data
from [-50,+150] seconds around the time of GRB 200228A.

All the requested event mode data was delivered to the ground.

In a ground analysis of the data, using the normal BAT imaging
technique, we detect GRB 200228A with a SNR of 40.

The BAT ground-calculated position is
RA, Dec = 333.8928, -42.9443 deg which is
   RA(J2000)  = 333d 53â€™ 34.08â€
   Dec(J2000) =  -42d 56' 39.48"
with an uncertainty of 3 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 34%.

This arcminute location is consistent with the localization region
distributed by the Fermi/GBM team (GCN. 27247).

No XRT or UVOT follow-up will take place due to the sourceâ€™s proximity
to the sun (0.5 hours).
We encourage follow-up from instruments capable of observing near the sun.


GRB_name: GRB200228A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27260
SUBJECT: GRB 200228A: Fermi GBM observation
DATE:    20/02/28 17:03:56 GMT
FROM:    Elisabetta Bissaldi at INFN,Bari  <elisabetta.bissaldi@ba.infn.it>

E. Bissaldi (Politecnico and INFN Bari)
reports on behalf of the Fermi GBM Team:


"At 06:58:33.81 UT on 28 February 2020, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 200228A (trigger 604565918 / 200228291), as reported
by the Fermi GBM Final Real-time Localization (GCN 27247).
The GBM localization is consistent with the Swift GUANO localization
(Tohuvavohu et al. 2020, GCN 27259).

The angle from the Fermi LAT boresight at the GBM trigger time is 33 degrees.

The GBM light curve consists of a single bright peak
with a duration (T90) of about 4 s (50-300 keV).
The time-averaged spectrum from T0 to T0+4 s is
adequately fit by a power law function with an exponential
high-energy cutoff.  The power law index is -0.61 +/- 0.04 and
the cutoff energy, parameterized as Epeak, is 165 +/- 5 keV.

The event fluence (10-1000 keV) in this time interval is
(6.44 +/- 0.13)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+1.0 s in the 10-1000 keV band
is 20.4 +/- 0.4 ph/s/cm^2.

A Band function fits the spectrum equally well
with Epeak= 153 +/- 7 keV, alpha = -0.54 +/- 0.05 and
beta = -2.85 +/- 0.23.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB200228C
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27261
SUBJECT: GRB 200228C: Insight-HXMT/HE detection
DATE:    20/02/28 17:24:58 GMT
FROM:    Qi Luo at IHEP  <luoqi@ihep.ac.cn>

Q. Luo, Y. G. Zheng, C. Cai, S. Xiao, Q. B. Yi, Y. F. DU, W. C. Xue, 
Y. Huang, C. K. Li, G. Li, X. B. Li, J. Y. Liao, S. L. Xiong,
C. Z. Liu, X. F. Li, Z. W. Li, Z. Chang, A. M. Zhang, 
Y. F. Zhang, X. F. Lu, C. L. Zou (IHEP), Y. J. Jin, 
Z. Zhang (THU), T. P. Li (IHEP/THU), F. J. Lu, L. M. Song, 
M. Wu, Y. P. Xu, S. N. Zhang (IHEP), 
report on behalf of the Insight-HXMT team:

At 2020-02-28T06:00:57.700 (T0), Insight-HXMT/HE detected 
GRB 200228C (trigger ID: HEB200228250) in a routine search of the data.

The Insight-HXMT/HE light curve mainly consists of multiple 
pulses with a duration (T90) of 3.375 s measured from T0-1.210 s. 
The 1-ms peak rate, measured from T0+0.091 s, is 2991 cnts/sec. 
The total counts from this burst is 5127 counts.
URL_LC: http://www.hxmt.org/images/GRB/HEB200228250_lc.jpg 

All measurements above are made with the CsI detectors operating in the 
regular mode with the energy range of about 80-800 keV (deposited energy). 
Only gamma-rays with energy greater than about 200 keV can penetrate 
the spacecraft and leave signals in the CsI detectors installed inside 
of the telescope. 

Insight-HXMT is the first Chinese space X-ray telescope, which was 
funded jointly by the China National Space Administration (CNSA) and 
the Chinese Academy of Sciences (CAS). 
More information about it could be found at: 
http://www.hxmt.org.


GRB_name: GRB200228B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27263
SUBJECT: GRB 200228B: KAIT Optical Upper Limit
DATE:    20/02/28 19:09:52 GMT
FROM:    Weikang Zheng at UC Berkeley  <weikang@berkeley.edu>

WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on
behalf of the KAIT GRB team:

The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at
Lick Observatory, responded to Swift GRB 200228B (Laha et al.,
GCN 27254) starting at 11:21:06 UT, 395 s after the burst.
Observations were performed with an automatic sequence in the
clear (roughly R), V, and I filters, and the exposure time was 20 s
per image. We do not detect any optical afterglow candidate within
the enhanced XRT position error circle (Evans et al., GCN 27256),
neither in single image, nor in the co-add images.
The typical limiting magnitude of our single clear image is about
18.0 mag calibrated to the Pan-STARRS1 catalog.


GRB_name: GRB200227A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27265
SUBJECT: GRB 200227A: RATIR Optical Observations 
DATE:    20/02/28 20:22:19 GMT
FROM:    Alan M Watson at UNAM  <alan@astro.unam.mx>

Alan M. Watson (UNAM), Nat Butler (ASU), Alexander Kutyrev (GSFC),
William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J.
Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI),
Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz
(UCSC), JesÃºs GonzÃ¡lez (UNAM), Carlos RomÃ¡n-ZÃºÃ±iga (UNAM), Harvey
Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (U. Wash.), and Vicki
Toy (UMD) report:

We observed the field of GRB 200227A (Laha et al., GCN Circ. 27234) with
the Reionization and Transients Infrared Camera (RATIR; www.ratir.org)
on the 1.5m Harold Johnson Telescope at the Observatorio AstronÃ³mico
Nacional on Sierra San Pedro MÃ¡rtir from 2020/02 28.17 to 2020/02 28.24
UTC (20.84 to 22.53 hours after the BAT trigger), obtaining a total of
0.69 hours exposure in the r and i bands.

For a source within the Swift-XRT enhanced error circle (Beardmore et
al., GCN Circ. 27243), in comparison with the SDSS DR9, we obtain the
following upper limits (3-sigma):

  r > 19.73
  i > 20.33

These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.

We thank the staff of the Observatorio AstronÃ³mico Nacional in San Pedro 
MÃ¡rtir.


GRB_name: GRB200228B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27266
SUBJECT: GRB 200228B: Fermi GBM observation
DATE:    20/02/28 20:54:53 GMT
FROM:    Joshua Wood at MSFC/Fermi-GBM  <joshua.r.wood@nasa.gov>

E. Bissaldi (Politecnico and INFN Bari), C. Meegan (UAH), and J. Wood (NASA/MSFC)
report on behalf of the Fermi GBM Team:

"At 11:14:43.89 UT on 28 February 2020, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 200228B (trigger 604581288 / 200228469),
which was also detected by the Swift/BAT (Laha et al. 2020, GCN 27254).
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 59 degrees.

The GBM light curve shows a single emission episode
with a duration (T90) of about 14 s (50-300 keV).
The time-averaged spectrum from T0-4 s to T0+11 s is
adequately fit by a power law function with an exponential
high-energy cutoff. The power law index is -1.17 +/- 0.33 and
the cutoff energy, parameterized as Epeak, is 76 +/- 16 keV.

The event fluence (10-1000 keV) in this time interval is
(1.30 +/- 0.18)E-07 erg/cm^2. The 1-sec peak photon flux measured
starting from T0-0.3 s in the 10-1000 keV band
is 1.4 +/- 0.2 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB200228B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27267
SUBJECT: GRB 200228B: RATIR Optical Observations
DATE:    20/02/28 21:07:26 GMT
FROM:    Emma Margarita Pereyra Talamantes at IA-UNAM Ensenada  <mpereyra@astro.unam.mx>

Margarita Pereyra (UNAM), Nat Butler (ASU), Alan M. Watson (UNAM),
Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer (UNAM),
Ori Fox (STScI), J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino
Cucchiara (UVI), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico
Ramirez-Ruiz (UCSC), JesÃºs GonzÃ¡lez (UNAM), Carlos RomÃ¡n-ZÃºÃ±iga (UNAM),
Harvey Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (U. Wash.), and
Vicki Toy (UMD) report:

We observed the field of GRB 200228B (Laha et al., GCN Circ. 27254) with
the Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on
the 1.5m Harold Johnson Telescope at the Observatorio AstronÃ³mico Nacional
on Sierra San Pedro MÃ¡rtir from 2020/02 28.48 to 2020/02 28.53 UTC (0.27 to
1.52 hours after the BAT trigger), obtaining a total of 0.62 hours exposure
in the r and i bands.

For a source within the Swift-XRT enhanced error circle (Evans et al., GCN
Circ. 27256), in comparison with the SDSS DR9 and 2MASS catalogs, we obtain
the following upper limits (3-sigma):

  r > 21.48
  i > 21.40

These magnitudes are in the AB system and are not  corrected for Galactic
extinction in the direction of the GRB.

We thank the staff of the Observatorio AstronÃ³mico Nacional in San Pedro
MÃ¡rtir.


-- 
*Dr. Margarita Pereyra *

*FFTF, Schlumberger Foundation Alumnae*
----------------------------------------------------------------------------------------------------------------

*CatedrÃ¡tico Conacyt*

*Instituto de AstronomÃ­a de la UNAM,*

*Km. 107 Carretera Tijua**na-Ensenada, *

*Ensenada Baja California, MÃ©xico. C.P. 22860*

Oficina: 405

Skype: margarita-pereyra


GRB_name: GRB200228B
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27268
SUBJECT: GRB 200228B: Swift/UVOT Upper Limits
DATE:    20/02/28 22:23:32 GMT
FROM:    Paul Kuin at MSSL  <npkuin@gmail.com>

N. P. M. Kuin (UCL-MSSL) and S. L. Laha (GSFC/UMBC/CRESST)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 200228B
137 s after the BAT trigger (Laha et al., GCN Circ. 27254).  No optical
afterglow consistent with the XRT position (Evans et al., GCN Circ.
 #27256 is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

u_FC               137          387          246         >20.1
v                 4992        10685          676         >20.1
b                 4580         6012          393         >20.6
u                  137         5807          442         >20.4
w1                5402         5602          197         >19.5
m2                5197         5396          197         >19.8
w2                4786         6218          393         >19.4

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.092 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB200228B
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27269
SUBJECT: Swift GRB 200228B: Global MASTER-Net observations report 
DATE:    20/02/29 00:12:08 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, 
V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva,
D.Kuvshinov,  D. Cheryasov
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile 
(Observatorio Astronomico Felix Aguilar OAFA),

H.Levato 
(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE),

R. Rebolo, M. Serra 
(The Instituto de Astrofisica de Canarias),

D. Buckley 
(South African Astronomical Observatory),

O.A. Gres, N.M. Budnev, O.Ershova 
(Irkutsk State University, API),

A. Tlatov, D. Dormidontov 
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich, Yu. Sergienko 
(Blagoveschensk Educational State University)




MASTER-Kislovodsk robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) was pointed to the Swift GRB 200228B ( S. Laha et al., GCN 27254) errorbox  45652 sec after trigger time at 2020-02-28 23:55:33 UT, with upper limit up to  18.6 mag. The observations began at zenith distance = 51 deg. The sun  altitude  is -41.7 deg. 

The galactic latitude b = 34 deg., longitude l = 36 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1300236

We obtain a following upper limits.  

Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________

   45742 |   MASTER-Kislovodsk |   C |   180 | 18.4 |        
   45742 |   MASTER-Kislovodsk |   C |   180 | 18.6 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.


GRB_name: GRB200228B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27270
SUBJECT: GRB 200228B: Swift-XRT refined Analysis
DATE:    20/02/29 05:26:50 GMT
FROM:    Kim Page at U.of Leicester  <klp5@leicester.ac.uk>

K.L. Page (U. Leicester) and S. Laha (GSFC/UMBC/CRESST) report on
behalf of the Swift-XRT team:

We have analysed 4.6 ks of XRT data for GRB 200228B (Laha et al. GCN
Circ. 27254), from 143 s to 18.2 ks after the  BAT trigger. The data
are entirely in Photon Counting (PC) mode. The enhanced XRT position
for this burst was given by Evans et al. (GCN Circ. 27256).

The light curve can be modelled with a power-law decay with a decay
index of alpha=0.65 (+0.10, -0.12).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 3.0 (+0.8, -0.7). The
best-fitting absorption column is  1.6 (+0.8, -0.6) x 10^22 cm^-2, in
excess of the Galactic value of 6.4 x 10^20 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 3.5 x 10^-11 (2.3 x 10^-10) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      1.6 (+0.8, -0.6) x 10^22 cm^-2
Galactic foreground: 6.4 x 10^20 cm^-2
Excess significance: 4.3 sigma
Photon index:      3.0 (+0.8, -0.7)

If the light curve continues to decay with a power-law decay index of
0.65, the count rate at T+24 hours will be 4.9 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.7 x
10^-13 (1.1 x 10^-12) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00958733.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB200228B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27271
SUBJECT: GRB 200228B: Liverpool Telescope imaging
DATE:    20/02/29 13:57:42 GMT
FROM:    Daniel Perley at Liverpool JMU  <d.a.perley@ljmu.ac.uk>

D. A. Perley and A. M. Cockeram (LJMU) report:

On 2020-02-29 UT we obtained imaging of the position of GRB 200228B 
(Fermi GBM team, GCN 27253; Laha et al., GCN 27254) using the 2m robotic 
Liverpool Telescope.  We collected 3x120s of exposure time in each of 
the the i-band and z-band filters, beginning at 05:53:44 and ending at 
06:07:33 (UTC).

No unambiguous source is detected in either stacked image, although a 
possible marginal (~3-sigma) source is present close to the center of 
the latest enhanced XRT error circle in the z-band image.  Photometry of 
this potential source (calibrating relative to PS1 catalog stars in the 
field) gives an approximate magnitude of z = 21.7 +/- 0.3.

3-sigma limits are:

dt(days)  filter   mag
0.7794    i       >22.6
0.7844    z       >21.7

We additionally note that Pan-STARRS1 imaging of the field shows several 
faint, probably-resolved sources close to the survey detection limit 
inside or closely outside the XRT error circle, which could represent a 
possible host galaxy or host group.

Imaging of the field is available at:
http://www.astro.ljmu.ac.uk/~aridperl/grb/200228b/GRB200228B_LT_PS1.png

(The enhanced XRT error circle is shown in cyan with the marginal 
"detection" highlighted in red.)










DisclaimerNone


GRB_name: GRB200228B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27272
SUBJECT: GRB 200228B: RATIR Optical Observations
DATE:    20/02/29 15:51:14 GMT
FROM:    Rosa Leticia Becerra Godinez at Inst. de Astronoma,UNAM  <rbecerra@astro.unam.mx>

Rosa L. Becerra (UNAM), Alan M. Watson (UNAM), Nat Butler (ASU),
Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer (UNAM),
Ori Fox (STScI), J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino
Cucchiara
(UVI), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico
Ramirez-Ruiz (UCSC), JesÃºs GonzÃ¡lez (UNAM), Carlos RomÃ¡n-ZÃºÃ±iga (UNAM),
Harvey Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (U. Wash.), and
Vicki Toy (UMD) report:

We observed the field of GRB 200228B (Fermi GBM team, GCN 27253,
Laha, et. al. GCN 27254) with the Reionization and Transients Infrared
Camera (RATIR; www.ratir.org) on the 1.5m Harold Johnson Telescope at the
Observatorio AstronÃ³mico Nacional on Sierra San Pedro MÃ¡rtir from 2020/02
29.36
to 2020/02 29.53 UTC (21.40 to 25.38 hours after the BAT trigger), obtaining
a total of 2.27 hours exposure in the r and i bands.

For a source within the Swift-XRT enhanced error circle (Evans et al., GCN
Circ. 27256),
in comparison with the SDSS DR9 and 2MASS catalogs, we obtain the following
upper
limits (3-sigma):

  r > 23.19
  i > 23.11

These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.

We thank the staff of the Observatorio AstronÃ³mico Nacional in San Pedro
MÃ¡rtir.


GRB_name: GRB200228B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27273
SUBJECT: GRB 200228B: Swift-BAT refined analysis
DATE:    20/02/29 23:49:33 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), H. A. Krimm (NSF),
S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC),
D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU), T. N. Ukwatta (LANL)
(i.e. the Swift-BAT team):

Using the data set from T-240 to T+297 sec from the recent telemetry
downlink,
we report further analysis of BAT GRB 200228B (trigger #958733)
(Laha et al., GCN Circ. 27254).  The BAT ground-calculated position is
RA, Dec = 252.007, 16.964 deg which is
   RA(J2000)  =  16h 48m 01.8s
   Dec(J2000) = +16d 57' 50.3"
with an uncertainty of 2.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 31%.

The mask-weighted light curve shows a weak pulse that starts at ~T-1 s,
peaks at ~T+2 s, and ends at ~T+7 s. T90 (15-350 keV) is 7.37 +- 1.58 sec
(estimated error including systematics).

The time-averaged spectrum from T-0.84 to T+6.97 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.27 +- 0.36.  The fluence in the 15-150 keV band is 3.0 +- 0.6 x 10^-7
erg/cm2.
The 1-sec peak photon flux measured from T+1.32 sec in the 15-150 keV band
is 1.0 +- 0.4 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/958733/BA/


GRB_name: GRB200228B
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27274
SUBJECT: GRB 200228B: LCO Optical Upper Limit
DATE:    20/03/01 11:29:15 GMT
FROM:    Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh@uvi.edu>

R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (U. of the Virgin Islands/College of Marin) report on behalf of a larger collaboration:

We observed Swift GRB 200228B (Laha et al., GCN 27254) with the LCO 1-m Sinistro instrument at the McDonald Observatory, Texas, USA site, on February 29, from 10:52 to 11:42 UT (corresponding to 23.4 to 24.5 hours after the GRB trigger time) with the Bessel I and R filters.

We performed a series of 10x120s exposures in I and R. We do not detect any uncatalouged sources in the individual frames (nor in stacked images) in the Swift error region.  Using the USNO-B.1 catalog as reference, we obtain the following 3-sigma upper limits in stacked images:

R > 22.08

I > 20.77

R.S. is funded by NSF AST grant #1831682


GRB_name: GRB200228B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27276
SUBJECT: GRB 200228B: Mondy, TSHAO, AbAO and CrAO optical observations, afterglow candidate
DATE:    20/03/01 15:21:19 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

A. Pozanenko (IKI), S. Belkin (IKI),  E. Klunko (ISTP), A. Kusakin 
(FAPHI),  I. Reva (FAPHI), V. Rumyantsev (CrAO), R. Ya. Inasaridze 
(AbAO), E. Mazaeva (IKI), A. Volnova (IKI) report on behalf of IKI-GRB-FuN:

We observed the field of GRB 200228B (Laha et al., GCN 27254; Fermi GBM 
Team, GCN 27253) with AZT-33IK 1.5-m telescope of Sayan observatory 
(Mondy) starting on Feb. 28 (UT) 19:24:43. We detected an optical object 
near the enhanced XRT position of the XRT afterglow (Evans et al., GCN 
27256). The object is absent in the Pan-STARRS DR1 catalog. The 
coordinates of the object are (J2000) 16:48:10.88 +16:59:04.5 with 
uncertainty of 0.5 arcsec in both coordinates. Next we observed the 
filed with Zeiss-1000 1-m telescope of Tien Shan Astronomical 
Observatory starting on Feb. 28 (UT) 23:08:56, Abastumani starting on 
Feb. 29 (UT) 01:38:45, Tien Shan Astronomical Observatory starting on 
Feb. 29 (UT) 23:08:56, and CrAO starting on Mar. 01 (UT) 00:58:28.

Preliminary photometry of the object and the field is following.

Date UT start       t-T0  Filter Exp. OT Err UL(3sigma)   telescope
                         (mid, days) (s)
2020-02-28 19:24:43 0.351  R 15*120 21.8  0.3  21.7 AZT-33IK
2020-02-28 23:08:56 0.516  R 3480   n/d   n/d  22.3 Z-1000
2020-02-29 01:38:45 0.616  R 46*60  n/d   n/d  21.8 AS-32
2020-02-29 22:22:37 n/a    R 5040   n/a   n/a  n/a  Z-1000
2020-03-01 00:58:28 1.594  R 31*120 22.05 0.09 23.8 ZTSh


Photometry is based on the USNO-B2.0 nearby stars.
USNO-B1.0    R2
1069-0297786 18.42
1069-0297719 18.25
1069-0297797 14.78

The finding chart is available at 
http://193.232.11.154/GRB200228B/GRB200228B_AZT33IK_Z1000_ZTSh_FC.png 
(or 
http://grb.iki.rssi.ru/GRB200228B/GRB200228B_AZT33IK_Z1000_ZTSh_FC.png ).

We suggest this object is a candidate in the afterglow of GRB 200228B 
after at least two epoch detections (see above), possible variability 
and absence of the bright object (R ~ 22) in the  Pan-STARRS DR1.

We did not detect any object at the position of NIR- candidate (Perley 
and  Cockeram, GCN 27271).


GRB_name: GRB200303A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27294
SUBJECT: GRB 200303A: Fermi GBM Final Real-time Localization
DATE:    20/03/03 02:44:36 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 02:34:23 UT on 3 Mar 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200303A (trigger 604895668.847358 / 200303107).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 207.4, Dec = 50.8 (J2000 degrees, equivalent to J2000 13h 49m, 50d 47'), with a statistical uncertainty of 3.8 degrees.

The angle from the Fermi LAT boresight is 108.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200303107/quicklook/glg_skymap_all_bn200303107.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200303107/quicklook/glg_healpix_all_bn200303107.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200303107/quicklook/glg_lc_medres34_bn200303107.gif


GRB_name: GRB200303A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27297
SUBJECT: GRB 200303A: Swift detection of a burst
DATE:    20/03/03 02:49:25 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>

S. B. Cenko (GSFC), S. D. Barthelmy (GSFC), C. Gronwall (PSU),
J.D. Gropp (PSU), N. J. Klingler (PSU), S. Laha (GSFC/UMBC/CRESST),
A. Y. Lien (GSFC/UMBC), F. E. Marshall (NASA/GSFC), M. J. Moss (GWU),
K. L. Page (U Leicester), D. M. Palmer (LANL) and
A. Tohuvavohu (U Toronto) report on behalf of the Neil Gehrels Swift
Observatory Team:

At 02:34:57 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 200303A (trigger=959431).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 212.698, +51.360, which is 
   RA(J2000)  =  14h 10m 47s
   Dec(J2000) = +51d 21' 35"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows a multi-peak
structure with a duration of about 60 sec.  The peak count rate
was ~3500 counts/sec (15-350 keV), at ~1 sec after the trigger. 

The XRT began observing the field at 02:36:25.1 UT, 87.7 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 212.7173, 51.3583 which is equivalent to:
   RA(J2000)  = 14h 10m 52.15s
   Dec(J2000) = +51d 21' 29.9"
with an uncertainty of 4.7 arcseconds (radius, 90% containment). This
location is 43 arcseconds from the BAT onboard position, within the BAT
error circle. No event data are yet available to determine the column
density using X-ray spectroscopy. 

The initial flux in the 2.5 s image was 8.77e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 96 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of
the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. 
The 8'x8' region for the list of sources generated on-board covers 100% of the
XRT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.02. 

This source lies within the current (Sector 22) field-of-view of TESS camera 3. 

Burst Advocate for this burst is S. B. Cenko (brad.cenko AT nasa.gov). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB200219C
Detection_method: VLA Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27298
SUBJECT: GRB 200219C: VLA Detection
DATE:    20/03/03 03:29:34 GMT
FROM:    Virginia Cunningham at U of MD  <vcunning@astro.umd.edu>

V. Cunningham (UMD), S. B. Cenko (NASA GSFC), S. Vogel (UMD)

We observed the Fermi GBM/LAT GRB 200219C (The Fermi GBM Team,
GCN 27145; Dirirsa et al., GCN 27151; Hamburg et al., GCN 27155) at 6 GHz
with the Karl G. Jansky Very Large Array (VLA) on 2020 Feb 25 11:23:02 UTC
(5.48 days post GBM trigger). We report a preliminary flux density of ~658 uJy
at position:

RA (J2000): 17:30:02.295 +/- 0.011
Dec (J2000): +10:32:22.237 +/- 0.011

This is consistent with the position of the potential host galaxy (Xu
et al., GCN
27161), optical afterglow (Reva et al., GCN 27162; Blazek et al., GCN 27166),
and X-ray afterglow (Burrows et al., GCN 27157).

We thank the VLA staff for their assistance in completing these observations.


GRB_name: GRB200303A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27300
SUBJECT: GRB 200303A: Enhanced Swift-XRT position
DATE:    20/03/03 07:27:17 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 822 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 200303A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 212.71895, +51.35930 which is equivalent
to:

RA (J2000): 14h 10m 52.55s
Dec (J2000): +51d 21' 33.5"

with an uncertainty of 1.7 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB200303A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27301
SUBJECT: GRB 200303A: CALET Gamma-Ray Burst Monitor detection
DATE:    20/03/03 09:23:42 GMT
FROM:    Valentin Pal'shin at AGU  <val@phys.aoyama.ac.jp>

Y. Asaoka (Waseda U),
A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U),
N. Cannady (GSFC/UMBC), M. L. Cherry (LSU),
S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

The long GRB 200303A (Fermi GBM Final Real-time Localization: Fermi GBM
Team, GCN Circ. 27294; Swift detection: Cenko et al., GCN Circ. 27297;
https://gcn.gsfc.nasa.gov/other/200303A.gcn3)
triggered the CALET Gamma-ray Burst Monitor (CGBM) at 02:34:20.728 UTC
on 3 March 2020. The burst signal was seen by all CGBM detectors.

The burst light curve shows a multi-peaked structure which starts at
T+2.3 sec, peaks at T+39.4 sec, and ends at T+88.8 sec.
The T90 and T50 durations measured by the SGM data are 68.9 +- 12.8 sec
and 28.9 +- 3.3 sec (40-1000 keV), respectively.

The ground processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1267237773/

The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at the Waseda University.


GRB_name: GRB200228A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27302
SUBJECT: GRB 200228A: AstroSat CZTI detection
DATE:    20/03/03 09:45:56 GMT
FROM:    Soumya Gupta at IUCAA/ASTROSAT  <soumya@iucaa>

S. Gupta, V. Sharma and D. Bhattacharya (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data showed the detection of the long GRB 200228A, which was also detected by Fermi GBM Final Real-time Localization (GCN #27247), BALROG (Kunzweiler F. et al., GCN #27248) and Swift/BAT (Tohuvavohu A. et al., GRB #27259).

The source was clearly detected in the 40-200 keV energy range. The light curve showed a single peak of emission peaking at 2020-02-28 06:58:33.01 UT. The measured peak count rate associated with the burst is 537 +/- 33.1 cts/s above the background in the combined data of four quadrants, with a total of 1496 +/- 9.8 cts. The local mean background count rate was 551 +/- 1.4 cts/s. Using cumulative rates, we measure a T90 of 4.8 +/- 0.02 s.

It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.

CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.


GRB_name: GRB200303A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27303
SUBJECT: GRB 200303A: Optical limit from CAHA
DATE:    20/03/03 11:24:50 GMT
FROM:    Antonio de Ugarte Postigo at IAA-CSIC  <deugarte@iaa.es>

A. de Ugarte Postigo (HETH/IAA-CSIC, DARK/NBI), D. A. Kann, C. Thoene,
J. F. Agui Fernandez, M. Blazek (all HETH/IAA-CSIC), R. Pedro Hedrosa (CAHA) 
report:

We observed the field of GRB 200303A (Cenko et al. GCN 27297) with CAFOS, 
on the 2.2 m telescope, at Calar Alto observatory (Almeria, Spain). Observations 
consisted of 5x360s in R-band with mean epoch 03:48:02 UT (1.249 hr after the 
burst).

Our initial analysis does not reveal any object within the refined error box (Goad 
et al. GCN 27300) down to a 3-sigma limit of R(AB) > 24.0 mag, with photometry 
performed against SDSS field stars.


GRB_name: GRB200303A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27304
SUBJECT: GRB 200303A: GOTO observations upper limit
DATE:    20/03/03 12:21:44 GMT
FROM:    Ben Gompertz at U of Warwick  <b.gompertz@warwick.ac.uk>

Y.-L. Mong (1); K. Ackley (1); D. K. Galloway (1); D. Steeghs (2); V. 
Dhillon (3); P. O'Brien (4); G. Ramsay (5); D. Pollacco (2); E. Thrane 
(1); S. Poshyachinda (6); R. Kotak (7); L. Nuttall (8); E. Pall\'e (9); 
K. Ulaczyk (2); J. Lyman (2); R. Cutter (2); A. Levan (2); T. Marsh (2); 
R. West (2); E. Stanway (2); B. Gompertz (2); K. Wiersema (2); T. 
Killestein (2); A. Casey (1); M. Brown (1); B. Muller (1); M. Dyer (3); 
J. Mullaney (3); E. Daw (3); S. Littlefair (3); J. Maund (3); L. 
Makrygianni (3); U. Burhanudin (3); R. Starling (4); R. Eyles (4); S. 
Tooke (4); S. Aukkaravittayapun (6); U. Sawangwit (6); S. Awiphan (6); 
D. Mkrtichian (6); P. Irawati (6); S. Mattila (7); T. Heikkil\"a (7); E. 
Rol (1)

((1) Monash University, (2) Warwick University, (3) University of 
Sheffield, (4) University of Leicester, (5) Armagh Observatory & 
Planetarium, (6) National Astronomical Research Institute of Thailand, 
(7) University of Turku, (8) University of Portsmouth, (9) Instituto de 
Astrofisica de Canarias)

report on behalf of the GOTO collaboration:

We carried out observations with the Gravitational-wave Optical 
Transient Observer (GOTO), in response to GRB 2000303A (Cenko et al. 
2020; GCN #27297; Fermi GBM; GCN #27294).

We made a series of 3 x 60 s exposures using our wide L-band filter 
(400-700 nm) covering the Swift XRT position (Cenko et al. 2020; GCN 
#27297), starting at 6.4 minutes after the Swift BAT trigger with 
midtime 02:52:17 UT on 03 March 2020.

Using a difference imaging analysis with recent survey observations of 
the same pointings as reference, we identify no viable afterglow 
candidate. Our mean 5-sigma detection limit was g=19.6 mag based on PS1 
catalogue calibrators.

GOTO is operated at the La Palma observing facilities of the University 
of Warwick on behalf of a consortium including the University of 
Warwick, Monash University, Armagh Observatory, the University of 
Leicester, the University of Sheffield, the National Astronomical 
Research Institute of Thailand (NARIT) and the Instituto de Astrofisica 
de Canarias (IAC) (https://goto-observatory.org)


GRB_name: GRB200219A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27305
SUBJECT: GRB 200219A: AstroSat CZTI detection
DATE:    20/03/03 12:36:27 GMT
FROM:    Soumya Gupta at IUCAA/ASTROSAT  <soumya@iucaa>

S. Gupta, V. Sharma and D. Bhattacharya (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:
Analysis of AstroSat CZTI data showed the detection of the short GRB 200219A, which was also detected by Fermi GBM Final Real-time (GCN #27123), Swift (Lien A. et al., GCN #27125), MASTER (Tiurina N. et al., GCN #27126), Swift-BAT (Laha S. et al., GCN #27148), FRAM-Auger (Jelinek M. et al., GCN #27164), UVOT (Siegel M. et al., GCN #27165), Konus-Wind (Svinkin D. et al., GCN #27226) and ATCA 5/9 GHz (Antonio D. et al., GCN #27245).
The source was clearly detected in the 40-200 keV energy range. The light curve showed a single peak of emission peaking at 2020-02-19 07:36:49 UT. The measured peak count rate associated with the burst is 426 +/- 30.7 cts/s above the background in the combined data of four quadrants, with a total of 413 +/- 4.4 cts. The local mean background count rate was 489 +/- 2.2 cts/s. Using cumulative rates, we measure a T90 of 1.1 +/- 0.45 s.
It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.
CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.


GRB_name: GRB200303A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27307
SUBJECT: GRB 200303A: FRAM-ORM optical limit 
DATE:    20/03/03 14:04:46 GMT
FROM:    Martin Jelinek at Astro.Inst-AVCR,Ondrejov  <martin.jelinek@asu.cas.cz>

Martin Jelinek, Jan Strobl (ASU CAS Ondrejov, CZ), Martin Masek, Petr
Janecek, Sergey Karpov, Jakub Jurysek, Jan Ebr, Ronan Cunniffe, Petr
Travnicek and Michael Prouza (Institute of Physics, Prague, CZ)

report:

The 25cm robotic telescope FRAM-ORM at La Palma (Spain) reacted robotically
to the GBM/Swift/CALET alert of GRB200303A (Cenko et al, GCNC 27297, Goad
et al. GCNC 27300, Asaoka et al. GCNC 27301 and Fermi GBM team GCNC 27294),
obtaining a series of 20s unfiltered images starting at 02:35:38.75UT, i.e.
41.3s post trigger.

We do not detect any new source in comparison to USNO-B2.0 catalog neither
in single images (3-sigma limit R>~17.9) nor in a combined 20x20s frame
(mean exp time 289s post trigger, 3-sigma limit R>~19.5) similarly to de
Ugarte et al. (GCNC 27303) and Mong et al. (GCNC 27304)


GRB_name: GRB200303A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27308
SUBJECT: GRB 200303A: Swift/UVOT Upper Limits
DATE:    20/03/03 15:21:17 GMT
FROM:    Alice Breeveld at MSSL-UCL  <a.breeveld@ucl.ac.uk>

A. A. Breeveld (UCL-MSSL) and S. B. Cenko (GSFC) report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of
GRB 200303A 96 s after the BAT trigger (Cenko et al., GCN Circ. 27297).
No optical afterglow consistent with the XRT position
(Goad et al. GCN Circ. 27300) is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC            96          246          147         >20.7
u_FC               308          558          246         >20.4
white               96         5034          550         >21.5
v                 1219         1238           19         >18.4
b                 1144         1163           19         >19.4
u                  308          558          246         >20.4

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB200303A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27309
SUBJECT: GRB 200303A: NOT optical observations
DATE:    20/03/03 15:25:21 GMT
FROM:    Luca Izzo at IAA-CSIC  <luca.izzo@gmail.com>

D. Xu (NAOC), L. Izzo (DARK/NBI),  D. B. Malesani (DTU Space), A.A. Djupvik (NOT), T. Pursimo (NOT) report on behalf of a larger collaboration:
We observed GRB 200303A (Fermi GBM team, GCN 27294, Cenko et al., GCN 27297, Asaoka et al., GCN 27301) with the Nordic Optical Telescope (NOT) equipped with StanCAM, covering 100% of the afterglow region as provided by the Swift-XRT (Cenko et al. 27297). We obtained 3x300 s exposures with the Bessel R filter starting at 03:36:18 UT on March 3 (median time 1.161 hr after the GRB trigger) and 5x200 s exposures with the z-SDSS filter starting at 03:53:59 UT (median time 1.483 hr). We do not detect any optical afterglow candidate down to a limit of R > 23.0 mag (AB) and z > 21.5 mag (AB), calibrated against PS1 catalog. 
With the above upper limits, the optical to X-ray spectral index is then beta_OX < -0.09 (Fnu propto nu^-beta) computed assuming the R-Bessel value and X-rays data from Swift-XRT. This suggests a â€˜â€™dark'' nature for GRB 200303A


GRB_name: GRB200303A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27311
SUBJECT: GRB 200303A: Swift-BAT refined analysis
DATE:    20/03/03 17:01:22 GMT
FROM:    Hans Krimm at NSF/NASA-GSFC  <hkrimm@nsf.gov>

D. M. Palmer (LANL), S. D. Barthelmy (GSFC), S. B. Cenko (GSFC), 
H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), T. Sakamoto (AGU), M. Stamatikos (OSU),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-240 to T+605 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 200303A (trigger #959431)
(Cenko, et al., GCN Circ. 27297).  The BAT ground-calculated position is
RA, Dec = 212.695, 51.358 deg which is 
  RA(J2000)  =  14h 10m 46.9s 
  Dec(J2000) = +51d 21' 29.3" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 59%.

The burst entered the BAT field of view around T-100 sec during a spacecraft slew.
The mask-weighted light curve shows a single episode with multiple pulses, 
starting at T-45 sec, peaking at the trigger time and returning to near background
by T+70 sec.  There is extended low-level emission out to nearly T+200 sec.
T90 (15-350 keV) is 94.2 +- 6.4 sec (estimated error including systematics).

The time-averaged spectrum from T-36.55 to T+193.26 sec is best fit by a power law
with an exponential cutoff.  This fit gives a photon index 1.39 +- 0.17, 
and Epeak of 131.4 +- 75.1 keV (chi squared 46.32 for 56 d.o.f.).  For this
model the total fluence in the 15-150 keV band is 1.3 +- 0.0 x 10^-5 erg/cm2
and the 1-sec peak flux measured from T+0.34 sec in the 15-150 keV band is
5.0 +- 0.3 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 1.65 +- 0.04 (chi squared 53.75 for 57 d.o.f.).  All the quoted errors
are at the 90% confidence level. 

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/959431/BA/


GRB_name: GRB200303A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27312
SUBJECT: GRB 200303A: Swift-XRT refined Analysis
DATE:    20/03/03 19:12:12 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester), K.L. Page (U.
Leicester), M.G. Bernardini (INAF-OAB), E. Ambrosi  (INAF-IASFPA) , M.
Capalbi (INAF-IASFPA), A. Tohuvavohu (U. Toronto), B. Sbarufatti (PSU),
D.N. Burrows (PSU) and S.B. Cenko report on behalf of the Swift-XRT
team:

We have analysed 6.6 ks of XRT data for GRB 200303A (Cenko et al. GCN
Circ. 27297), from 77 s to 41.6 ks after the  BAT trigger. The data
comprise 582 s in Windowed Timing (WT) mode (the first 9 s were taken
while Swift was slewing) with the remainder in Photon Counting (PC)
mode. The enhanced XRT position for this burst was given by Goad et al.
(GCN Circ. 27300).

The late-time light curve (from T0+4.8 ks) can be modelled with a
power-law decay with a decay index of alpha=1.27 (+0.09, -0.10).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.41 (+/-0.05). The
best-fitting absorption column is  1.10 (+0.05, -0.04) x 10^22 cm^-2,
in excess of the Galactic value of 1.6 x 10^20 cm^-2 (Willingale et al.
2013). The PC mode spectrum has a photon index of 2.38 (+0.15, -0.14)
and a best-fitting absorption column of 7.5 (+1.0, -0.9) x 10^21 cm^-2.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum  is 3.7 x 10^-11 (8.8 x 10^-11) erg cm^-2
count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      7.5 (+1.0, -0.9) x 10^21 cm^-2
Galactic foreground: 1.6 x 10^20 cm^-2
Excess significance: 13.4 sigma
Photon index:      2.38 (+0.15, -0.14)

If the light curve continues to decay with a power-law decay index of
1.27, the count rate at T+24 hours will be 0.043 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.6 x
10^-12 (3.8 x 10^-12) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00959431.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB200210A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27313
SUBJECT: GRB200210A AstroSat observations
DATE:    20/03/04 04:52:33 GMT
FROM:    Tilak Katoch at TIFR  <tilak@tifr.res.in>

H. M. Antia, Tilak Katoch, Parag Shah, Dhiraj Dedhia (TIFR),
S. Gupta, R. Gaikwad, V. Sharma, A. Vibhute and D. Bhattacharya (IUCAA) 
on
behalf of the AstroSat LAXPC and CZTI collaboration report:

Analysis of AstroSat LAXPC and CZTI data showed the detection of a long 
GRB 2002010A.

The source was clearly detected in the 3-400 keV energy range. The light 
curve showed
multiple peaks of emission with the strongest peak at 2020-02-10 
08:03:40.00 UT. The
measured peak count rate above the background associated with the burst 
is 354 +/- 29 cts/s
in LAXPC10 and 197 +/- 21 in LAXPC20, with a total of 5524 +/- 143 cts 
in LAXPC10 and
3384 +/- 99 in LAXPC20. LAXPC20 has a nominal energy range of 3-100 keV 
but due to lower
gain in LAXPC10 the energy range is about 30-400 keV. The background 
subtracted light curve
with 1 sec time-bin in LAXPC detectors is available at the web-site:

  https://www.tifr.res.in/~astrosat_laxpc/grb200210lc.jpg

The measured peak count rate associated with the burst in CZTI is 288 
+/- 29 cts/s above
the background in the combined data of four quadrants, with a total of 
6338 +/- 67 cts.
The local mean background count rate was 533 +/- 15 cts/s. Using 
cumulative rates, we
measure a T90 of 29.2 +/- 0.01 s. CZTI operates in the energy range of 
40-200 keV. It was
also clearly detected in the CsI anticoincidence (Veto) detector in the 
100-500 keV energy
range.

CZTI GRB detections are reported regularly on the payload site at
http://astrosat.iucaa.in/czti/?q=grb.

LAXPC is built by TIFR in collaboration with the Indian Space Research 
Organisation.
CZTI is built by a TIFR-led consortium of institutes across India, 
including VSSC, ISAC,
IUCAA, SAC and PRL. The Indian Space Research Organisation funded, 
managed and
facilitated the project.


GRB_name: GRB200303A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27314
SUBJECT: GRB 200303A: Fermi GBM observation
DATE:    20/03/04 10:26:57 GMT
FROM:    Elisabetta Bissaldi at INFN,Bari  <elisabetta.bissaldi@ba.infn.it>

C. Malacaria (NASA-MSFC/USRA) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:


"At 02:34:23.85 UT on 03 March 2020,
the Fermi Gamma-Ray Burst Monitor (GBM) triggered
and located GRB 200303A (trigger 604895668 / 200303107),
which was also detected by the Swift/BAT and Swift/XRT
(Cenko et al. 2020, GCN 27297, Goad et al. 2020, GCN 27300).
The Fermi GBM Final Real-time Localization (GCN 27294)
is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time
is 106 degrees.

The GBM light curve shows a complex structure
with a duration (T90) of about 82 s (50-300 keV).
The time-averaged spectrum from T0-2.8 s to T0+95.7 s is
best fit by a Band function with Epeak = 151 +/- 18 keV,
alpha = -1.26 +/- 0.05, and beta = -2.14 +/- 0.10.

The event fluence (10-1000 keV) in this time interval is
(3.23 +/- 0.08)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+35.1 s in the 10-1000 keV band
is 9.2 +/- 0.4 ph/s/cm^2.


The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official
Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB200303A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27316
SUBJECT: Konus-Wind observation of GRB200303A
DATE:    20/03/04 18:11:22 GMT
FROM:    Anastasia Tsvetkova at Ioffe Institute  <tsvetkova@mail.ioffe.ru>

A. Tsvetkova, S. Golenetskii, R.Aptekar, D. Frederiks,
M. Ulanov, D. Svinkin, A. Lysenko, A. Ridnaia and T. Cline
on behalf of the Konus-Wind team, report:

The long-duration GRB200303A
(Swift detection of a burst: Cenko et al., GCN 27297;
Palmer et al., GCN 27311;
CALET Gamma-Ray Burst Monitor detection:
Asaoka et al., GCN 27301;
Fermi GBM observation: Malacaria & Meegan, GCN 27314)
triggered Konus-Wind at T0=9268.336 s UT (02:34:28.336).

The burst light curve shows a multi-peaked structure
which starts at ~T0-4.0 s and has a total duration of~67.1 s.
The emission is seen up to ~10 MeV.

As observed by Konus-Wind, the burst
had a fluence of 3.88(-1.20,+0.80)x10^-5 erg/cm2,
and a 64-ms peak energy flux, measured from T0+32.800 s,
of 2.38(-0.96,+1.15)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-integrated spectrum of the burst
(measured from T0 to T0+65.792 s)
is best fit in the 20 keV - 3 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -1.25(-0.21,+0.28),
the high energy photon index beta = -2.17(-7.83,+0.18),
the peak energy Ep = 154(-44,+82) keV,
chi2 = 72/66 dof.

The spectrum near the peak count rate
(measured from T0+24.832 to T0+41.216 s)
is best fit in the 20 keV - 10 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -1.39(-0.14,+0.20),
the high energy photon index beta = -2.54(-7.46,+0.45),
the peak energy Ep = 183(-53,+54) keV,
chi2 = 80/86 dof.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB200303_T09268/

All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.


GRB_name: GRB200228B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27318
SUBJECT: GRB 200228B: continued optical observations
DATE:    20/03/05 18:07:39 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

A. Pozanenko (IKI), S. Belkin (IKI), R. Ya. Inasaridze (AbAO),  E. 
Klunko (ISTP), A. Kusakin (FAPHI),  I. Reva (FAPHI), V. Rumyantsev 
(CrAO), E. Mazaeva (IKI), A. Volnova (IKI) report on behalf of IKI-GRB-FuN:

We continue observations of the OT (Pozanenko et al., GCN 27276) 
associated with GRB 200228B (Laha et al., GCN 27254; Fermi GBM Team, GCN 
27253) with AZT-33IK 1.5-m telescope of Sayan observatory (Mondy) and 
AS-32 telescope of Abastumani Astrophysical observatory. The OT is well 
observable (see photometry below in the table) and current XRT position 
( https://www.swift.ac.uk/xrt_positions/00958733/ ) coincides with 
position of the OT.

Preliminary photometry of the object following.

Date UT start       t-T0  Filter Exp. OT Err UL(3sigma)   telescope
                         (mid, days) (s)
2020-03-03 01:36:36 3.6186   R 58*60  21.65 0.13  22.6 AS-32
2020-03-03 21:03:33 4.4228   R 20*120 22.2  0.4   22.0 AZT-33IK
2020-03-04 23:44:59 5.5488   R 80*60  21.93 0.17  22.6 AS-32

Photometry is based on the USNO-B2.0 nearby stars used in previous 
observations (GCN 27276).

The light curve in R-filter is available at 
http://grb.rssi.ru/GRB200228B/GRB200228B_lc_2.png

We urge on spectroscopic and multicolor photometry to classify the OT.


GRB_name: GRB200306A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27320
SUBJECT: GRB 200306A: Swift detection of a burst
DATE:    20/03/06 00:38:35 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

K. K. Simpson (PSU), D. M. Palmer (LANL) and B. Sbarufatti (PSU)
report on behalf of the Neil Gehrels Swift Observatory Team:

At 00:19:40 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 200306A (trigger= 959917).  Swift slewed immediately to the burst. 
Due to communications outages, no BAT data is immediately available at this 
time, but the complete data set will be available after upcoming downlinks 
to the ground. 

Using promptly downlinked data we find a bright, uncatalogued X-ray
source with an enhanced position: RA, Dec 101.1050, -62.0058 which is
equivalent to:
   RA(J2000)  = 06h 44m 25.20s
   Dec(J2000) = -62d 00' 20.9"
with an uncertainty of 3.6 arcseconds (radius, 90% containment). This
position may be improved as more data are received; the latest position
is available at https://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 8.67
x 10^20 cm^-2 (Willingale et al. 2013). 

The initial flux in the 2.5 s image was 3.02e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of nominal 150.000 seconds with the
White  filter starting 85s seconds after the BAT trigger. Automatic
processing failed because of connectivity issues on the ground. 
Further analysis will be available once the full dataset gets on the
ground. 

Burst Advocate for this burst is K. K. Simpson (kira.simpson1984 AT gmail.com). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB200306A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27321
SUBJECT: GRB 200306A: Potential LCO Optical Afterglow Detection
DATE:    20/03/06 06:15:31 GMT
FROM:    Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh@uvi.edu>

R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (U. of the Virgin Islands/College of Marin) report on behalf of a larger collaboration:

We observed Swift GRB 200306A (Simpson et al., GCN 27320) with the LCO 1-m Sinistro instrument at the Cerro Tololo Interamerican Observatory, Chile site, on March 6, from 1:06 to 1:46 UT (corresponding to 0.78 to 1.45 hours from the GRB trigger time) with the Bessel I and R filters.

We performed a series of 5x240s exposures in I and R.  We detect a faint source in stacked R band images within the XRT error region that is not present in USNO or 2MASS catalogs.  We do not detect a source in stacked I band images.  Using the USNO-B.1 catalog as reference, we obtain the following magnitude detection in R at RA,DEC=101.1054814,-62.0049360 and the following 3-sigma upper limit in I:

R = 21.75

I > 21.52

R.S. is funded by NSF AST grant #1831682


GRB_name: GRB200306B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27323
SUBJECT: GRB 200306B: Fermi GBM Final Real-time Localization
DATE:    20/03/06 22:35:47 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely SHORT GRB

At 22:25:25 UT on 6 Mar 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200306B (trigger 605226330.32671 / 200306934).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 267.0, Dec = 24.5 (J2000 degrees, equivalent to J2000 17h 48m, 24d 30'), with a statistical uncertainty of 135.1 degrees.

The angle from the Fermi LAT boresight is 4.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200306934/quicklook/glg_skymap_all_bn200306934.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200306934/quicklook/glg_healpix_all_bn200306934.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200306934/quicklook/glg_lc_medres34_bn200306934.gif


GRB_name: GRB200306C
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27326
SUBJECT: GRB 200306C: Swift detection of a burst with an optical counterpart
DATE:    20/03/06 23:02:02 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

J.D. Gropp (PSU), S. D. Barthelmy (GSFC), D. N. Burrows (PSU),
J. A. Kennea (PSU), S. Laha (GSFC/UMBC/CRESST),
A. Y. Lien (GSFC/UMBC), F. E. Marshall (NASA/GSFC),
D. M. Palmer (LANL), B. Sbarufatti (PSU), M. H. Siegel (PSU) and
A. Tohuvavohu (U Toronto) report on behalf of the Neil Gehrels Swift
Observatory Team:

At 22:50:39 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 200306C (trigger=960102).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 198.582, +11.255 which is 
   RA(J2000) = 13h 14m 20s
   Dec(J2000) = +11d 15' 18"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a complex
structure with a duration of about 50 sec.  The peak count rate
was ~1800 counts/sec (15-350 keV), at ~3 sec after the trigger. 

The XRT began observing the field at 22:52:35.9 UT, 116.9 seconds after
the BAT trigger. Using promptly downlinked data we find a fading,
uncatalogued X-ray source located at RA, Dec 198.55562, 11.26981 which
is equivalent to:
   RA(J2000)  = 13h 14m 13.35s
   Dec(J2000) = +11d 16' 11.3"
with an uncertainty of 3.5 arcseconds (radius, 90% containment). This
location is 107 arcseconds from the BAT onboard position, within the
BAT error circle. This position may be improved as more data are
received; the latest position is available at
https://www.swift.ac.uk/sper. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value (1.91 x
10^20 cm^-2, Willingale et al. 2013), with an excess column of 2.8
(+2.73/-2.37) x 10^21 cm^-2 (90% confidence). 

UVOT took a finding chart exposure of 250 seconds with the U filter starting
117 seconds after the BAT trigger. There is a candidate afterglow in the list
of sources generated on-board at
  RA(J2000)  = 13:14:13.44 = 198.55602
  DEC(J2000) = +11:16:11.5  =  11.26985
with a 90%-confidence error radius of about 1.10 arc sec. This position is 1.4
arc sec. from the center of the XRT error circle. The estimated magnitude is
17.47. No correction has been made for the expected extinction corresponding to
E(B-V) of 0.02. 

Burst Advocate for this burst is J.D. Gropp (jdg44 AT psu.edu). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB200306C
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27328
SUBJECT: GRB 200306C: FRAM-ORM afterglow detection
DATE:    20/03/06 23:48:16 GMT
FROM:    Martin Jelinek at Astro.Inst-AVCR,Ondrejov  <martin.jelinek@asu.cas.cz>

Martin Jelinek, Jan Strobl (ASU CAS Ondrejov, CZ),
Sergey Karpov, Martin Masek, Petr Janecek, Jakub Jurysek,
Jan Ebr, Ronan Cunniffe, Petr Travnicek and Michael Prouza
(Institute of Physics, Prague, CZ)

report:

The 25cm robotic telescope FRAM-ORM at La Palma (Spain)
reacted robotically to the alert of GRB200306C (Gropp
et al GCNC 27326), obtaining a series of 20 s unfiltered
images starting at 22:51:39.3 UT, i.e. 60.3s post trigger.

We clearly detect the source reported by (Gropp et al
GCN 27326 and Lipunov et al GCN 27325), decaying at a
rate of alpha ~ 1.4 +- 0.1.  The brightness of the object
was R = 14.1 the first image.


GRB_name: GRB200306C
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27329
SUBJECT: GRB 200306C: BOOTES-1 detection of the optical afterglow
DATE:    20/03/07 00:04:48 GMT
FROM:    Alberto J. Castro-Tirado at IAA-CSIC  <ajct@iaa.es>

Y.-D. Hu, A. J. Castro-Tirado and E. Fernandez-Garcia (IAA-CSIC), C. 
Perez del Pulgar, A. Reina, A. Castellon, I. Carrasco, I. Perez-Garcia 
(UMA), F. Rendon (IAA-CSIC and INTA-CEDEA), on behalf of a larger 
collaboration, report:

The 30cm BOOTES-1 robotic telescope at INTA-CEDEA in Huelva (Spain) 
automatically responded to the Swift trigger of GRB 200306C (Gropp et 
al., GCNC 27326). A sequence of 1-s images (clear filter) were obtained 
starting at 22:52:28 UT (i.e. 109s after the burst). At the UVOT 
position reported by Swift an optical transient is detected with R = 
14.9, in agreement with the MASTER (Lipunov et al. GCNC 27324) and FRAM 
detections (Jelinek et al. GCNC 27328). A detailed analysis for the 
sequence of images which were obtained is ongoing. The magnitude is 
calibrated against the USNO-B1 catalog and is not corrected for Galactic 
extinction in the direction of the GRB.

We thank the staff at INTA-CEDEA for its excellent support.


GRB_name: GRB200306A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27331
SUBJECT: GRB 200306A: Swift-XRT refined Analysis
DATE:    20/03/07 00:38:06 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), E. Ambrosi 
(INAF-IASFPA) , M. Capalbi (INAF-IASFPA), M. Perri (ASDC), B.
Sbarufatti (PSU), D.N. Burrows (PSU), J. D. Gropp (PSU), A.P. Beardmore
(U. Leicester) and K.K. Simpson report on behalf of the Swift-XRT team:

We have analysed 2.1 ks of XRT data for GRB 200306A (Simpson et al. GCN
Circ. 27320), from 66 s to 6.2 ks after the  BAT trigger. The data
comprise 186 s in Windowed Timing (WT) mode (the first 9 s were taken
while Swift was slewing) with the remainder in Photon Counting (PC)
mode. Using 2051 s of PC mode data and 6 UVOT images, we find an
enhanced XRT position (using the XRT-UVOT alignment and matching UVOT
field sources to the USNO-B1 catalogue): RA, Dec = 101.10233, -62.00654
which is equivalent to:

RA (J2000): 06h 44m 24.56s
Dec(J2000): -62d 00' 23.5"

with an uncertainty of 1.5 arcsec (radius, 90% confidence).

The light curve can be modelled with a power-law decay with a decay
index of alpha=4.05 (+/-0.21).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.93 (+/-0.14). The
best-fitting absorption column is  5.2 (+/-0.5) x 10^21 cm^-2, in
excess of the Galactic value of 8.6 x 10^20 cm^-2 (Willingale et al.
2013). The PC mode spectrum has a photon index of 1.89 (+0.19, -0.18)
and a best-fitting absorption column of 4.3 (+1.1, -0.9) x 10^21 cm^-2.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum  is 4.2 x 10^-11 (6.3 x 10^-11) erg cm^-2
count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      4.3 (+1.1, -0.9) x 10^21 cm^-2
Galactic foreground: 8.6 x 10^20 cm^-2
Excess significance: 6.0 sigma
Photon index:      1.89 (+0.19, -0.18)

If the light curve continues to decay with a power-law decay index of
4.05, the count rate at T+24 hours will be 3.6 x 10^-11 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.5 x
10^-21 (2.3 x 10^-21) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00959917.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB200306C
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27332
SUBJECT: GRB 200306C: GOTO upper limits
DATE:    20/03/07 00:57:36 GMT
FROM:    Kendall Ackley at Monash University  <kendall.ackley@monash.edu>

K. Ackley (1); K. Wiersema (2); Y.-L. Mong (1); D. K. Galloway (1);
D. Steeghs (2); V.Dhillon (3); P. O'Brien (4); G. Ramsay (5);
D. Pollacco (2); E. Thrane (1); S. Poshyachinda (6); R. Kotak (7);
L. Nuttall (8); E. Pall\'e (9); K. Ulaczyk (2); J. Lyman (2);
R. Cutter (2); A. Levan (2); T. Marsh (2); R. West (2); E. Stanway (2);
B. Gompertz (2);  T. Killestein (2); A. Casey (1); M. Brown (1);
B. Muller (1); M. Dyer (3); J. Mullaney (3); E. Daw (3);
S. Littlefair (3); J. Maund (3); L. Makrygianni (3); U. Burhanudin (3);
R. Starling (4); R. Eyles (4); S. Tooke (4); S. Aukkaravittayapun (6);
U. Sawangwit (6); S. Awiphan (6); D. Mkrtichian (6); P. Irawati (6);
S. Mattila (7); T. Heikkil\"a (7); E. Rol (1)
((1) Monash University, (2) Warwick University, (3) University of
Sheffield, (4) University of Leicester, (5) Armagh Observatory &
Planetarium, (6) National Astronomical Research Institute of Thailand,
(7) University of Turku, (8) University of Portsmouth, (9) Instituto
de Astrofisica de Canarias)

report on behalf of the GOTO collaboration:

We carried out observations with the Gravitational-wave Optical
Transient Observer (GOTO), in response to GRB 2000306C
(Palmer et al. 2020; GCN #27326).

We made a series of 9x60 s exposures using our wide L-band filter
(400-700 nm) covering the Swift UVOT position (Palmer et al. 2020; GCN
#27326), starting at 1.1 hours after the Swift BAT trigger with
midtime 23:56:45 UT on 06 March 2020.

Using a difference imaging analysis with recent survey observations
of the same pointings as reference, we do not identify the detections
from MASTER (Lipunov et al. GCN #27324), FRAM (Jelinek et al. GCN #27328),
and BOOTES-1 (Castro-Tirado et al. GCN #27329). Our mean 5-sigma detection
limit was g=19.1 mag based on PS1 catalogue calibrators.


GOTO is operated at the La Palma observing facilities of the
University of Warwick on behalf of a consortium including the
University of Warwick, Monash University, Armagh Observatory, the
University of Leicester, the University of Sheffield, the National
Astronomical Research Institute of Thailand (NARIT) and the Instituto
de Astrofisica de Canarias (IAC) (https://goto-observatory.org)


GRB_name: GRB200306C
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27333
SUBJECT: GRB 200306C: SAO RAS observations of OT
DATE:    20/03/07 01:20:14 GMT
FROM:    Moskvitin Alexander at SAO RAS  <mosk@sao.ru>

A. Moskvitin on behalf of the larger GRB follow-up team report.

We observed the field of the GRB 200306C (Gropp et al. GCNC #27326)
with the 1-m telescope of SAO RAS in BVRc filters. The observations
were started in semi-automatic mode since 2 minutes after the trigger.

We clearly detected the OT discovered by Swift/UVOT, MASTER-Net
(Lipunov et al. GCNC #27324/27325/27327), FRAM-ORM (Jelinek et al.
GCNC #27328), BOOTES-1 (Hu et al., GCNC #27329) with the coordinates:
R. A. = 13:14:13.44, Decl. = +11:16:11.8 +/- 0".5, Epoch = 2000.0.

Preliminary R band photometry of the OT:

Tmid-T0, s   exp., s   Rmag +/- err

151          30        15.29 +/- 0.06
183          30        15.77 +/- 0.03
230          30        15.97 +/- 0.12
276          30        16.14 +/- 0.04
388          60        16.49 +/- 0.05
464          60        16.69 +/- 0.07
541          60        16.99 +/- 0.04

The calibration were done against nearby SDSS stars (Lupton, 2005).


GRB_name: GRB200306C
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27334
SUBJECT: GRB 200306C: Liverpool Telescope observations
DATE:    20/03/07 02:09:10 GMT
FROM:    Luca Izzo at DARK/NBI  <luca.izzo@gmail.com>

L. Izzo (DARK/NBI) and D. Perley (LJMU) report:

We observed GRB 200303C (Gropp et al. GCN 27326) with the IO:O camera mounted on the 2-m Liverpool Telescope located in La Palma, Spain. Observations started on March 7th at 01:01:49 UT (2.20 hours after the GRB trigger) and we obtained a series of 5x60s images in the griz filters.

In our stacked i-band and z-band images we detect the afterglow at the position reported by Swift-UVOT and other telescopes (Lipunov et al. GCNC 27324, GCN 27325; Jelinek et al. GCN 27328; Hu et al., GCN 27329; Moskvitin GCN 27333) and we measure a preliminary magnitude of i(AB) = 20.7 +- 0.1 mag (median time 2.46 hr after the GRB trigger) and z(AB) = 21.0 +- 0.3 mag (median time 2.58 hr after the GRB).  

[GCN OPS NOTE(07mar20): Per author's request, in the first sentence "200303A" was changed to "200303C".
Also per request, the thrid paragraph was removed as it was an accidental inclusion of a previous circular.]


GRB_name: GRB200306C
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27335
SUBJECT: GRB 200306C: OSN 1.5m afterglow detection
DATE:    20/03/07 02:51:33 GMT
FROM:    Alexander Kann at IAA-CSIC  <kann@iaa.es>

D. A. Kann, M. Blazek (both HETH/IAA-CSIC), A. de Ugarte Postigo 
(HETH/IAA-CSIC, DARK/NBI), C. C. Thoene, J. F. Agui Fernandez (both 
HETH/IAA-CSIC), and V. Casanova (IAA-CSIC) report:

We observed the optical afterglow position of GRB 200306C (Lipunov et 
al., GCNs #27324, #27325; Gropp et al., GCN #27326; Jelinek et al., GCN 
#27328; Hu et al., GCN #27329; Moskvitin, GCN #27333; Izzo & Perley, GCN 
#27334) with the 1.5m telescope of the Sierra Nevada Observatory, 
Granada, Spain, in the V filter. Observations began 46 minutes after the 
GRB, and we obtained 18 x 30 s images under moonlight. We also obtained 
four Rc images before technical problems shut down the telescope, but 
stray light from a nearby bright star precludes a detection.

We detect the afterglow in a stacked image centered 0.03985 days after 
the GRB, at V = 19.38 +/- 0.14 mag (Vega mag).

The afterglow magnitude was measured against six comparison stars from 
the GSC 2.3 catalog.


GRB_name: GRB200306B
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27336
SUBJECT: GRB 200306B: Fermi GBM Final Localization Correction
DATE:    20/03/07 04:20:53 GMT
FROM:    Joshua Wood at MSFC/Fermi-GBM  <joshua.r.wood@nasa.gov>

"The Fermi GBM team reports the detection of a likely Short GRB.

At 22:25:25 UT on 6 Mar 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200306B (trigger 605226330.32671 / 200306934). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 349.5, Dec = 5.1 (J2000 degrees, equivalent to J2000 23h 18m, 5d 06'), with a statistical uncertainty of 28.0 degrees. The angle from the Fermi LAT boresight is 85.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200306934/quicklook/glg_skymap_all_bn200306934.png

The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200306934/quicklook/glg_healpix_all_bn200306934.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200306934/quicklook/glg_lc_medres34_bn200306934.gif"


GRB_name: GRB200306C
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  27337
SUBJECT: GRB 200306C: LCO Optical Upper Limits
DATE:    20/03/07 07:28:15 GMT
FROM:    Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh@uvi.edu>

R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (U. of the Virgin Islands/College of Marin) report on behalf of a larger collaboration:

We observed Swift GRB 200306C (Gropp et al., GCN 27326) with the LCO 1-m Sinistro instrument at the Cerro Tololo Interamerican Observatory, Chile site, on March 7, from 4:50 to 5:21 UT (corresponding to 6.0 to 6.5 hours from the GRB trigger time) with the Bessel I and R filters.

We performed a series of 5x120s exposures in I and R. We do not detect any sources in the individual frames (nor in stacked images) at the location of previous optical afterglow detections (Lipunov et al., GCN 27325, Jelinek et al., GCN 27328, Castro-Tirado et al., GCN 27329, Moskvitin et al., GCN 27333, Izzo et al., GCN 27334, Kann et al., 27335).  Using the USNO-B.1 catalog as reference, we obtain the following 3-sigma upper limits:

R > 20.56

I > 19.65

R.S. is funded by NSF AST grant #1831682


