Introduction
Searches for high-energy neutrinos from the Sun are currently the most sensitive means of probing spin-dependent interactions between protons and most models for dark matter. In 2013, the IceCube Collaboration published the world’s best limits on the spin-dependent cross section for weakly interacting dark matter particles.
Today, we present an improved event-level likelihood formalism for including neutrino telescope data in global fits to new physics. We derive limits on spin-dependent dark matter-proton scattering by employing the new formalism in a re-analysis of data from the 79-string IceCube search for dark matter annihilation in the Sun, including explicit energy information for each event. We also apply the new analysis to the weak-scale minimal supersymmetric standard model (MSSM), excluding a number of models for the first time.
This is the data release accompanying this paper. We are also providing the nulike code, which allows to apply the new likelihood formalism to arbitrary dark matter models.
“Improved limits on dark matter annihilation in the Sun with the 79-string IceCube detector and implications for supersymmetry,” IceCube Collaboration: M.G.Aartsen et al, Submitted to the Journal of Cosmology and Astroparticle Physics. arxiv.org/abs/1601.00653
Data release
The 79-string IceCube search for dark matter.
Click here to download (.zip, 760KB)
These data correspond to the three orthogonal event selections that were used in the analysis and are also described in the published paper (Phys. Rev. Lett. 110, 131302 (2013)). These selections are labeled according to their expected event topologies as winter high-energy (WH), winter low-energy (WL), and summer low-energy (SL).
Files IC79_Events_xx.txt
Data for each event selection is given in ASCII format and contains the following information per event:
- Reconstructed zenith [radians]
- Reconstructed azimuth [radians]
- Reconstructed angle of muon candidate event relative to Sun position – cos(φ)
- Energy proxy, Nchanc
- Paraboloid sigma (uncertainty on the reconstructed direction) [degrees]
- Event time stamp, in units of year, day, second, and also MJD (four entries in total)
Files IC79_Background_distributions_xx.txt.
The total number of background events per event selection is provided with the background probability density functions (PDFs) of the angular distribution between the reconstructed track and the position of the Sun in 1-degree bins. The PDFs of the background in Nchanc is also provided.
Files IC79_Effective_Area_xx.txt and IC79_Effective_Volume_xx.txt.
For calculations of expected event rates, we provide the muon effective volume [km3] and the neutrino effective area [m2]. These detector efficiencies can be convoluted with a theoretical neutrino flux to give a predicted event rate. Aνeff indicates the area of an equivalent detector 100 percent sensitive to through-going neutrinos. Vμeff corresponds to an equivalent volume of 100% detection efficiency for muons. Both efficiencies are an average over the detector up-time for the corresponding event selections. For each efficiency, we also show the median angular error, the median of the angle between the reconstructed muon and the neutrino direction. For completeness, the median angular error is provided with respect to neutrino and muon energy.
Files IC79_energy_histograms_xx.txt
The energy response for different intervals in truth muon energy (Eμ in GeV) in form of probability distributions in Ncchan are also provided.
The computer code used, which can be used to apply the new likelihood to arbitrary dark matter models, can be downloaded here.
For any questions about this data release, please write to data@icecube.wisc.edu.