Distances to Supernova Remnants G$20.4+0.1$, G$24.7-0.6$ and G$28.6-0.1$ and New Molecular Cloud Associations

TL;DR

This study determines accurate distances to three supernova remnants using HI absorption and molecular cloud data, revealing their likely associations and refining their distance estimates.

Contribution

The paper introduces a method combining HI absorption spectra and molecular cloud analysis to accurately measure SNR distances and identify new associations.

Findings

Distances to G20.4+0.1, G24.7-0.6, G28.6-0.1 are 7.8, 3.8, and 9.6 kpc respectively.

The SNRs are likely associated with molecular clouds.

New distance estimates improve understanding of SNR properties.

Abstract

Accurate distances to supernova remnants (SNRs) are crucial in determining their size, age, luminosity and evolutionary state. To determine distances, we chose three SNRs from the VLA Galactic Plane Survey (VGPS) for extraction of HI absorption spectra. Analysing HI absorption spectra, $^{13}$CO emission spectra, and HI and $^{13}$CO channel maps, kinematic velocities (or their limits) to the three SNRs were calculated. The three SNRs are probably associated with molecular clouds and the new distance to G$20.4+0.1$, G$24.7-0.6$ and G$28.6-0.1$ are $7.8 \pm0.5$ kpc, $3.8\pm 0.2 $ kpc and $ 9.6 \pm 0.3 $ kpc, respectively.