Energy Determination and Gamma/Hadron Separation Using the Lateral Distribution of EAS for the 100 TeV Gamma-Ray Astronomy

Abstract:

More than 100 gamma-ray sources have been detected by the Cherenkov telescopes in the energies from sub-TeV to multi-TeV. On the other hand, the extensive air shower (EAS) arrays, such as the Tibet air shower array, the ARGO-YBJ and the Milagro, have observed several gammaray sources with the wide field of view and higher energy threshold than the Cherenkov telescopes. Aiming at 100 TeV gamma-ray astronomy, the Tibet water-Cherenkov-type muon detector (MD) array (∼ 4000m2) was constructed under the Tibet air shower (AS) array (∼ 37000m2), and the data taking was started in 2014 [1]. This AS+ MD array will significantly improve gamma-ray sensitivity in 10-1000 TeV region by means of gamma/hadron separation based on counting the number of muons accompanying an air shower [2, 3]. In this work, we will mainly study the energy determination of gamma-ray-induced air showers in the 10-1000 TeV energy region using the lateral distribution of EAS by Monte Carlo (MC) simulation assuming the Tibet AS array. We will also show possibility of selecting gamma-ray showers from the hadron backgrounds using the age parameter of the air shower. It is noted that the muon information measured by the the MD array is not used to select gamma-ray showers in this study.

Año de publicación:

2015

Keywords:

Fuente:

google