Gamma-ray Astronomy with Muons: Sensitivity of IceCube to PeVatrons in the Southern Sky

TL;DR

This paper assesses IceCube's ability to detect PeVatrons in the southern sky by analyzing muon fluxes from gamma-ray sources, demonstrating potential detection capabilities comparable to northern observatories within a decade.

Contribution

It introduces an analytic method to estimate muon fluxes from gamma-ray showers and evaluates IceCube's sensitivity to southern sky PeVatrons, expanding gamma-ray source detection strategies.

Findings

Detection possible in 10 years for sources with fluxes > 3×10^{-11} particles TeV^{-1} cm^{-2} s^{-1}.

IceCube can identify PeVatrons similar to Milagro in the southern sky.

Analytic approach enables flux estimation from gamma-ray showers.

Abstract

Northern hemisphere TeV gamma-ray observatories such as Milagro and Tibet AS$\gamma$ have demonstrated the importance of all-sky instruments by discovering previously unidentified sources that may be the PeVatrons producing cosmic rays up to the "knee" in the cosmic ray spectrum. We evaluate the potential of IceCube to identify similar sources in the southern sky by detailing an analytic approach to determine fluxes of muons from TeV gamma-ray showers. We apply this approach to known gamma-ray sources such as supernova remnants. We find that, similar to Milagro, detection is possible in 10 years for point-like PeVatrons with fluxes stronger than several 10^{-11} particles TeV^{-1} cm^{-2} s^{-1}.