Cosmic Ray Energy Spectrum and Mass Composition from 10^15 to 10^17 eV by Data of the Tunka EAS Cherenkov Array

Budnev, N. M.; Chernov, D. V.; Gress, O. A.; Gress, T. I.; Korosteleva, E. E.; Kuzmichev, L. A.; Lubsandorzhiev, B. K.; Pankov, L. V.; Parfenov, Yu. V.; Prosin, V. V.; Semeney, Yu. A.; Spiering, Ch.; Wischnewski, R. P.; Yashin, I. V.

Cosmic Ray Energy Spectrum and Mass Composition from 10^15 to 10^17 eV by Data of the Tunka EAS Cherenkov Array

Authors

Lubsandorzhiev, B. K.

Pankov, L. V.

Parfenov, Yu. V.

Prosin, V. V.

Description

We present results of an improved analysis of the experimental data of the EAS Cherenkov array Tunka-25. A new function to fit the Cherenkov light lateral distribution LDF at core distances from 0 to 350 m has been developed on the base of CORSIKA simulations and applied to the analysis of Tunka data. Two methods to estimate the EAS maximum position have been used. The one is based on the pulse FWHM, the other on the light LDF. We present the primary energy spectrum in the energy range 10^15 - 10^17 eV. The use of the depth of the EAS maximum to determine the mean mass composition is discussed.
4 pages, 4 figures, reported at ICRC2005, rus-prosin-VV-abs2-he12-oral