Lateral density and arrival time distributions of Cherenkov photons in extensive air showers: a simulation study

Abstract

We have investigated some features of the density and arrival time distributions of Cherenkov photons in extensive air showers using the CORSIKA simulation package. The main thrust of this study is to see the effect of hadronic interaction models on the production pattern of Cherenkov photons with respect to distance from the shower core. Such studies are very important in ground based $\gamma$-ray astronomy for an effective rejection of huge cosmic ray background, where the atmospheric Cherenkov technique is being used extensively within the energy range of some hundred GeV to few TeV. We have found that for all primary particles, the density distribution patterns of Cherenkov photons follow the negative exponential function with different coefficients and slopes depending on the type of primary particle, its energy and the type of interaction model combinations. Whereas the arrival time distribution patterns of Cherenkov photons follow the function of the form $t(r)=t_0{e}^{\Gamma /r^{\lambda }}$, with different values of the function parameters. There is no significant effect of hadronic interaction model combinations on the density and arrival time distributions for the $\gamma$-ray primaries. However, for the hadronic showers, the effects of the model combinations are significant under different conditions.

arXiv comment12 pages, 10 figures in Published in Astroparticle Physics, 2015

References in corpus (7)

• Cerenkov Photon Density Fluctuations in Extensive Air Showers
• Possible Discrimination between Gamma Rays and Hadrons using Cerenkov Photon Timing Measurements
• Simulation Studies on Arrival Time Distributions of Cherenkov Photons in Extensive Air Showers
• Measurable difference in Cherenkov light between gamma and hadron induced EAS
• Angular Resolution of the Pachmarhi Array of Cerenkov Telescopes
• Gamma-Hadron Separation using Cerenkov Photon Density Fluctuations
• Gamma Ray and Hadron generated Čerenkov Photon Spectra at Various Observation Altitudes

Cited by in corpus (2)

• Muons as a tool for background rejection in Imaging Atmospheric Cherenkov Telescope arrays
• A simulation study on few parameters of Cherenkov photons in extensive air showers of different primaries incident at various zenith angles over a high altitude observation level