Hybrid cosmic ray measurements using the IceAct telescopes in coincidence with the IceCube and IceTop detectors

TL;DR

This paper reports on the first analysis of hybrid cosmic ray events detected by IceAct telescopes in coincidence with IceCube and IceTop, demonstrating improved composition studies and detector calibration potential at the South Pole.

Contribution

It introduces the use of IceAct Cherenkov telescopes for hybrid cosmic ray detection alongside IceCube, enhancing particle discrimination and calibration methods.

Findings

IceAct telescopes detect Cherenkov light emissions from cosmic ray showers.

Hybrid measurements improve primary particle type discrimination.

Two years of data demonstrate the telescopes' performance and potential.

Abstract

IceAct is a proposed surface array of compact (50 cm diameter) and cost-effective Imaging Air Cherenkov Telescopes installed at the site of the IceCube Neutrino Observatory at the geographic South Pole. Since January 2019, two IceAct telescope demonstrators, featuring 61 silicon pho- tomultiplier (SiPM) pixels have been taking data in the center of the IceTop surface array during the austral winter. We present the first analysis of hybrid cosmic ray events detected by the IceAct imaging air-Cherenkov telescopes in coincidence with the IceCube Neutrino Observatory, includ- ing the IceTop surface array and the IceCube in-ice array. By featuring an energy threshold of about 10 TeV and a wide field-of-view, the IceAct telescopes show promising capabilities of im- proving current cosmic ray composition studies: measuring the Cherenkov light emissions in the atmosphere adds new information about the shower development not accessible with the current detectors, enabling significantly better primary particle type discrimination on a statistical basis. The hybrid measurement also allows for detailed feasibility studies of detector cross-calibration and of cosmic ray veto capabilities for neutrino analyses. We present the performance of the telescopes, the results from the analysis of two years of data, and an outlook of a hybrid simulation for a future telescope array.