CORSIKA bug and other updates Dmitry Chirkin UC Berkeley
CORSIKA updates • Track times are given relative to the shower core arrival to the surface • F2k and related fixes: track numbers and parent ids (treated by ucr), p->Z1 • All coordinates are given at the observation level (ice surface), track length now exact • Shower times can now be assigned and coincident showers can be treated (by combining them within a predefined time window)
CORSIKA bug • CORSIKA version 6.023 and earlier had muon radiative energy losses underestimated by 103. As of version 6.030 this is corrected. Effect on the background calculation is minor.
Nch distributions • To estimate the differences between different CORSIKA versions and CR spectrum models, and effect of the coincident showers on the background simulation, Nch distributions are compared.
Spectrum index corrections 1st method • results 2nd method
CORSIKA updates (continued) • Possible to choose between Wiebel-Sooth and Jorg Horandel published primary spectra. The latter is implemented within the poli-gonato model of the CR energy spectrum. This implementation is now valid up to 50 PeV
Poli-gonato CR spectrum fits • From J-H
Conclusions • Many updates to CORSIKA were implemented • CORSIKA bug is corrected in current version (6.030) and has no effect on the background muon simulation • Coincident shower events do not significantly affect the background simulation • Change from Wiebel-Sooth CR spectra to the Jorg Horandel poli-gonato model does affect the background simulation, the change in spectral index is of the order 0.02
Auxiliary slides • Spectrum correction depth profiles
Spectrum corrections method 1st method • Also my spectrum corrections method was applied 2nd method