Infrared and X-ray study of the Galactic SNR G15.9+0.2

TL;DR

This study combines high-resolution X-ray and infrared data to analyze the Galactic SNR G15.9+0.2, revealing its young age, ejecta features, and environmental interactions, including a confirmed central compact object.

Contribution

It provides a detailed multi-wavelength analysis of G15.9+0.2, confirming the nature of the CCO and identifying ejecta components, which advances understanding of its physical properties and environment.

Findings

SNR G15.9+0.2 is a few thousand years old.

Emission dominated by shocked interstellar medium.

Ejecta emission with enhanced elemental abundances detected.

Abstract

G15.9+0.2 is a Galactic shell-type supernova remnant (SNR), which was detected in radio and has been confirmed in X-rays based on Chandra observations. An X-ray point source CXOUJ181852.0-150213 has been detected and suggested to be an associated neutron star. In a recent study, we have confirmed the source to be a central compact object (CCO). We have studied the SNR using high-resolution X-ray data taken with Chandra in combination with infrared (IR) data in order to understand its emission and to derive its physical parameters. This will also help to constrain, e.g., the age of the CCO and the environment in which it was born. The spectral analysis of the X-ray emission using the new Chandra data and the comparison to the IR data have shown that the SNR is relatively young with an age of a few thousand years and that its emission is dominated by that of shocked interstellar medium (ISM). However, the analysis of the spectrum of the bright eastern shell shows that there is an additional emission component with enhanced abundances of {\alpha} elements and Fe, suggesting ejecta emission. The multi-wavelength emission is consistent with SNR G15.9+0.2 expanding in an ISM with a density gradient, while there is also colder material located in front of the SNR, which absorbs its thermal X-ray emission in the softer bands.