University of Wisconsin-Madison

First Year Performance Paper - Section 6.1

6.1 String-21 and AMANDA

Figure 29 shows the zenith and azimuthal distributions for AMANDA coincidences with String-21. There are two peaks in the azimuthal distribution separated by 180° depending on which detector the muon hits first. The relative population of the two peaks is determined by the convolution of the geometry of the two detectors with the steeply peaked zenith angle distribution of atmospheric muons. IceCube is deeper than AMANDA, so most muons go through AMANDA first. The corresponding shift in the zenith angle distribution is apparent in the scatter plot, which is shown in Fig. 30.

Scatter plot of directions of AMANDA-String21 coincidences.
Scatter plot of directions of AMANDA-String21 coincidences.