Distances of Galactic Supernova Remnants Using Red Clump Stars

TL;DR

This study uses red clump stars as standard candles to independently measure distances to 15 supernova remnants in the Galaxy's first quadrant, providing new distance estimates and constraints, and validating the method's effectiveness.

Contribution

The paper introduces the use of red clump stars for independent distance measurements of supernova remnants, including first-time distance estimates for several SNRs.

Findings

Distances for 15 SNRs are well determined.

First-time distance estimates for G65.8-0.5, G66.0-0.0, and G67.6+0.9.

Most measurements agree with previous results.

Abstract

We carry out a project to independently measure the distances of supernova remnants (SNRs) in the first quadrant of the Galaxy. In this project, red clump (RC) stars are used as standard candles and extinction probes to build the optical extinction (A$_V$) - distance(D) relation in each direction of extinction-known SNRs. 15 SNRs' distances are well determined. Among them, the distances of G65.8-0.5, G66.0-0.0 and G67.6+0.9 are given for the first time. We also obtain 32 upper/lower limits of distances, and the distances to G5.7-0.1, G15.1-1.6, G28.8+1.5 and G78.2+2.1 are constrained. Most of the distances measured by the RC method are consistent with previous results. The RC method provides an independent access to the distances of SNRs.