Document Type : Original Article

Authors

• Zainab A. Nasser ¹
• Itab Hussein ²
• Al-Rubaiee Ahmed ¹

¹ Department of Physics, College of Science, Mustansiriyah University, Baghdad, Iraq

² department of physics,college of science,Mustansiriyah university

Abstract

This work investigates the properties of the Lateral Distribution Function (LDF) of gamma-ray-induced Extensive Air Showers (EAS) across a large energy range from (1015 to 1020) eV, which includes the knee and ankle energy regions. The AIRES (AIR-shower Extended Simulations) system was used in simulations to generate secondary gamma rays, with primary protons serving as initiating particles. Hadronic interaction models, particularly QGSJET-04-II and EPOS-LHC, were used to explore the impact of alternative physical assumptions on shower development. The lateral distribution of secondary gamma rays was studied systematically at various primary energy and zenith angles. The findings show that the LDF is clearly dependent on primary energy, with considerable differences between the knee and ankle regions. Furthermore, zenith angles have a major influence on the lateral dispersion of gamma rays, emphasizing differences in particle interactions and shower dynamics. The sigmoidal function was used to set the lateral distribution coefficient curves of EAS, generating new coefficients as a function of primary energy. These findings provide vital insights into the behavior and detection of gamma-ray-induced EAS, increasing our knowledge of high-energy astrophysics and cosmic-ray studies.

Keywords

• AIRES system
• LDF
• Ankle and Knee regions
• Sigmoidal function

Main Subjects

• Nuclear Physics