Parametric Analysis of Cherenkov Light LDF from EAS for High Energy Gamma Rays and Nuclei: Ways of Practical Application

In this paper we propose a 'knee-like' approximation of the lateral distribution of the Cherenkov light from extensive air showers in the energy range 30-3000 TeV and study a possibility of its practical application in high energy ground-based gamma-ray astronomy experiments (in particular, in TAIGA-HiSCORE). The approximation has a very good accuracy for individual showers and can be easily simplified for practical application in the HiSCORE wide angle timing array in the condition of a limited number of triggered stations.Comment: 4 pages, 5 figures, proceedings of ISVHECRI 2016 (19th International Symposium on Very High Energy Cosmic Ray Interactions

Method of Separation Between Light and Heavy Groups of Primary CR Nuclei by LDF of Cherenkov Light in the Range 300–3000 TeV

The problem of chemical composition below the knee in the cosmic-ray energy spectrum has not yet been solved due to low statistics collected from direct experiments. In the HiSCORE experiment the lateral distribution functions (LDF) of Cherenkov light of EASs with energy greater than hundreds of TeV can be measured in detail for millions of individual events. A full steepness of LDF is sensitive to the depth of shower maximum and as a result to primary particle type. In this paper, we developed a parametric method of separation between heavy and light groups of nuclei using the ’knee-like’ approximation of LDF and taking into account measurement uncertainty

Calorimetric studies of chalcogenide glasses in the system Se-S

Differential scanning calorimetry measurements under non-isothermal conditions were performed on the chalcogenide glasses Se98−x Sx Sn2 (x = 8, 18) and Se77 S20 X3 (X = Sn, Pb). The values of the glass transition temperature and crystallization temperature were found to depend on the heating rate. The activation energy for the glass transition and the activation energy for crystallization were calculated from the heating rate-dependence. The thermal stability and the glass forming tendency were calculated and they were found to have the same trend

Application of New Approximations of the Lateral Distribution of EAS Cherenkov Light in the Atmosphere

A new knee-like approximation of the lateral distribution function (LDF) of EAS Cherenkov light in the 30–3000 TeV energy range was proposed and tested with simulated showers in our earlier studies. This approximation fits the LDFs of individual showers accurately for all types of primary particles gamma-rays, protons, and nuclei) and is suitable for reconstructing the shower core, determining the energy, and separating gamma-induced showers from hadron-induced ones. In the present study, the knee-like fitting function is used to determine the parameters of real showers detected by TAIGA-HiSCORE. It is demonstrated that this approximation characterizes properly all types of individual LDFs of experimental events in the 300–1000 TeV range. The accuracy of fit is governed by fluctuations intrinsic to the process of measurement of the Cherenkov photon density. The probability density function of these fluctuations was reconstructed and introduced into simulations. Certain useful methodical applications of the knee-like approximation are con-sidered, and the possibility of shower sorting into nuclei groups is examined. The extensive statistical coverage and detailed LDF measurement data of HiSCORE have provided the first opportunity to examine in depth the LDF of Cherenkov radiation in the 300–1000 TeV range