A Two-Component Lateral Distribution Function for the Reconstruction of Air-Shower Events in IceTop

TL;DR

This paper introduces a two-component lateral distribution function (LDF) to estimate low-energy muons in cosmic-ray air showers detected by IceTop, improving event reconstruction without dedicated muon detectors.

Contribution

A novel two-component LDF approach for event-by-event estimation of low-energy muons in IceTop air-shower measurements.

Findings

Effective separation of electromagnetic and muon signals in IceTop data.

Improved accuracy in reconstructing primary energy and muon content.

Potential for better testing of hadronic interaction models.

Abstract

The surface component of the IceCube Neutrino Observatory, IceTop, consists of an array of ice-Cherenkov tanks measuring the electromagnetic signal as well as low-energy ($\sim\rm{GeV}$) muons from cosmic-ray air showers. In addition, accompanying high-energy (above a few $100\,\rm{GeV}$) muons can be observed in coincidence in the deep in-ice detector. A combined measurement of the low- and high-energy muon content is of particular interest for tests of hadronic interaction models as well as for cosmic-ray mass discrimination. However, since IceTop does not feature dedicated muon detectors, an estimation of the low-energy muon component of individual air showers is challenging. In this work, a two-component lateral distribution function (LDF), using separate descriptions for the electromagnetic and muon lateral distributions of the detector signals, is introduced as a new approach for the estimation of low-energy muons in air showers on an event-by-event basis. The principle of the air-shower reconstruction using the two-component LDF, as well as its reconstruction performance with respect to primary energy and number of low-energy muons will be discussed.