%0 Journal Article
%T Extension of Cherenkov Light LDF Approximation for Yakutsk EAS Array
%A A. A. Al-Rubaiee
%A Y. Al-Douri
%A U. Hashim
%J Journal of Astrophysics
%D 2014
%R 10.1155/2014/492814
%X The simulation of the Cherenkov light lateral distribution function (LDF) in extensive air showers (EAS) was performed using CORSIKA code for configuration of Yakutsk EAS array at high energy range for different primary particles (p, Fe, and O2) and different zenith angles. Depending on Breit-Wigner function a parameterization of Cherenkov light LDF was reconstructed on the basis of this simulation as a function of primary energy. A comparison of the calculated Cherenkov light LDF with that measured on the Yakutsk EAS array gives the possibility of identification of the particle initiating the shower and determination of its energy in the knee region of the cosmic ray spectrum. The extrapolation of approximated Cherenkov light LDF for high energies was obtained for primary proton and iron nuclei. 1. Introduction Study of the energy spectrum and mass composition of primary cosmic rays (PCRs) in the energy range 1013¨C1017£żeV is of a special interest in connection with observed index change of PCR spectrum close to £żPeV which is called the Ħ°kneeĦħ region [1, 2]. The Cherenkov light emitted in the atmosphere by relativistic electrons of cosmic rays (CRs) in EAS carries important information about the shower development and PCR particles. The Cherenkov light LDF depends on energy and type of the primary particle, observation level, height of the first interaction, and direction of shower axis [3]. The Monte Carlo method is one of the necessary tools of numerical simulation for investigation of EAS characteristics and experimental data processing and analysis (determination of the primary particle energy type and direction of shower axis from the characteristics of Cherenkov radiation of secondary charged particles). Agnetta et al. [4] have discussed the simulation and the experimental setup with detailed information on the detection of Cherenkov light method in EAS. On the other side, Akchurin et al. [5] have presented detailed measurements of high-energy electromagnetic and hadronic shower profiles. The Cherenkov light LDF generated in the shower development process was measured for electrons in the energy range 8¨C200£żGeV. The Cherenkov light profiles are discussed and compared with results of Monte Carlo simulations. Berezhnev et al. [6] have installed the Cherenkov light EAS array (Tunka-133). This array permits a detailed study of cosmic ray energy spectrum and mass composition in the energy range 1016¨C1018£żeV with a uniform method. The analysis of LDF and time structure of EAS Cherenkov light allowed estimating the depth of the EAS maximum . In the
%U http://www.hindawi.com/journals/jas/2014/492814/