Cygnus X-3 Revisited: 10 Years of Muon and Radio Observations

TL;DR

This study analyzes a decade of underground muon and radio observations of Cygnus X-3, finding potential correlations between muon flux excesses and major radio flares, suggesting possible high-energy particle emissions from the source.

Contribution

It provides a long-term analysis of muon flux from Cygnus X-3 and investigates its correlation with radio flares, offering new insights into high-energy processes in the source.

Findings

Some muon flux excesses coincide with major radio flares.

Muon events may be distributed around Cygnus X-3 with a Gaussian spread.

Instrumental angular spread verified by moon shadow observation.

Abstract

The Soudan 2 deep underground tracking calorimeter has recorded cosmic ray muon tracks from the direction of the galactic x-ray binary Cygnus X-3 on most transits during the interval 1989-1998. We analyze these events in the context of previous reports of Cygnus X-3-related muon flux during major radio flares of that source. We find some evidence for excess flux during a small number of transits coincident with major radio flares. We also find an indication that these events may be distributed around the source with a Gaussian point spread function with $\sigma = 1.3^{\circ}$, larger than the instrumental angular spread of $\le 0.3^{\circ}$, verified by observation of the shadow of the moon.