Results on the primary CR spectrum and composition reconstructed with the SPHERE-2 detector

Abstract

First preliminary results of the balloon-borne experiment SPHERE-2 on the all-nuclei primary cosmic rays (PCR) spectrum and primary composition are presented. The primary spectrum in the energy range $10^{16}$--$5\cdot 10^{17}$ eV was reconstructed using characteristics of Vavilov-Cherenkov radiation of extensive air showers (EAS), reflected from a snow surface. Several sources of systematic uncertainties of the spectrum were analysed. A method for separation of the primary nuclei' groups based on the lateral distribution function' (LDF) steepness parameter is presented. Preliminary estimate of the mean light nuclei' fraction $f_{30-150}$ at energies $3\cdot 10^{16}$--$1.5\cdot 10^{17}$ eV was performed and yielded $f_{30-150}$= (21$\pm$11)%.

4 pages, 2 figures, Proc. 23rd European Cosmic Ray Symposium, to appear in J. Phys. Conf. Ser

References in corpus (3)

• Kneelike structure in the spectrum of the heavy component of cosmic rays observed with KASCADE-Grande
• All-particle primary energy spectrum in the 3-200 PeV energy range
• Possibility of Using a Satellite-Based Detector for Recording Cherenkov Light from Ultrahigh-Energy Extensive Air Showers Penetrating into the Ocean Water

Cited by in corpus (3)

• The SPHERE-2 detector for observation of extensive air showers in 1 PeV -- 1 EeV energy range
• Spatial and temporal structure of EAS reflected Cherenkov light signal
• Event-by-event study of CR composition with the SPHERE experiment using the 2013 data