Towards a cosmic-ray mass-composition study at Tunka Radio Extension (ARENA 2016)

TL;DR

This paper investigates methods to determine the mass composition of cosmic rays using radio detection at Tunka-Rex, focusing on the slope of the lateral distribution function and systematic uncertainties from different primary particles.

Contribution

It introduces a model-independent approach to improve primary mass reconstruction and analyzes systematic uncertainties using advanced simulations.

Findings

Largest uncertainty in energy deposit is due to unknown primary particle

Studied the relation between polarization and LDF asymmetry

Proposed improvements for primary mass reconstruction

Abstract

The Tunka Radio Extension (Tunka-Rex) is a radio detector at the TAIGA facility located in Siberia nearby the southern tip of Lake Baikal. Tunka-Rex measures air-showers induced by high-energy cosmic rays, in particular, the lateral distribution of the radio pulses. The depth of the air-shower maximum, which statistically depends on the mass of the primary particle, is determined from the slope of the lateral distribution function (LDF). Using a model-independent approach, we have studied possible features of the one-dimensional slope method and tried to find improvements for the reconstruction of primary mass. To study the systematic uncertainties given by different primary particles, we have performed simulations using the CONEX and CoREAS software packages of the recently released CORSIKA v7.5 including the modern high-energy hadronic models QGSJet-II.04 and EPOS-LHC. The simulations have shown that the largest systematic uncertainty in the energy deposit is due to the unknown primary particle. Finally, we studied the relation between the polarization and the asymmetry of the LDF.