Estimating the mass of cosmic rays by combining radio and muon measurements

• Main Author: Holt Ewa M.
• Format: Article
• Language: English
• Published: EDP Sciences 2019-01-01
• Series: EPJ Web of Conferences
• Online Access: https://www.epj-conferences.org/articles/epjconf/pdf/2019/21/epjconf_arena2018_02002.pdf

The Auger Engineering Radio Array (AERA) is a radio detector at the Pierre Auger Observatory and it is dedicated to measure the radio emission of cosmic-ray air showers. AERA is co-located with the underground muon detectors of the Auger Muons and Infill for the Ground Array (AMIGA). This provides a perfect setup to experimentally test the benefits of combining muons and radio emission for estimating the primary mass. We have investigated this combination using air-shower simulations. We compared the performance for mass separation of this new method to alternative methods in which the electrons and muons are measured with particle detectors at the surface. Forshowers with zenith angles below 50° the new method is of comparable performance, and for showers more inclinedthan 50° it is clearly superior. Therefore, measuring the radio signal in addition to the muons significantly improves the mass sensitivity compared to techniques using solely particle measurements.