Evolutionary Models for 15 Galactic Supernova Remnants with New Distances

TL;DR

This study applies evolutionary models to 15 Galactic supernova remnants with new distance measurements, estimating their physical parameters and comparing their explosion energies and densities to those in the Large Magellanic Cloud.

Contribution

It provides the first detailed modeling of these remnants using recent distance data, estimating key physical properties and comparing Galactic and LMC supernova characteristics.

Findings

Explosion energy distribution similar to LMC SNRs.

Galactic SNRs have higher mean densities than LMC SNRs.

Estimated supernova birth rate and sample incompleteness.

Abstract

Recent studies using 21 cm HI line and $^{13}$CO line observations in the inner part of the Galaxy have resulted in new distances for 30 Galactic supernova remnants (SNRs). 15 of those remnants have observed X-ray spectra, for which shocked-gas temperatures and emission measures are measured. Here we apply spherically symmetric SNR evolution models to these 15 remnants to obtain estimates for ages, explosion energies, circum-stellar medium densities and profiles (uniform or wind-type).From the distribution of ages we obtain a supernova birth rate and estimate incompleteness. The energies and densities can be well fit with log-normal distributions. The distribution of explosion energies is very similar to that of SNRs in the Large Magellanic Cloud (LMC), suggesting SN explosions in the LMC and in the Galaxy are very similar. The density distribution has higher mean density for Galactic SNRs than for LMC SNRs, by a factor $\sim$2.5.