New XMM-Newton observations of faint, evolved supernova remnants in the Large Magellanic Cloud

TL;DR

This study uses XMM-Newton, optical, radio, and infrared data to confirm and characterize faint, evolved supernova remnants in the Large Magellanic Cloud, revealing new remnants and details about their physical states.

Contribution

First deep X-ray observations of ten LMC objects, confirming seven as SNRs and identifying new evolved remnants, expanding the known SNR population in the LMC.

Findings

Confirmed seven new SNRs in the LMC.

Identified two evolved Fe-rich remnants and a potential pulsar wind nebula.

Increased the total number of known LMC SNRs by ~10%.

Abstract

The Large Magellanic Cloud (LMC) hosts a rich population of supernova remnants (SNRs), our knowledge of which is the most complete of any galaxy. However, there remain many candidate SNRs, identified through optical and radio observations where additional X-ray data can confirm their SNR nature and provide details on their physical properties. In this paper we present XMM-Newton observations that provide the first deep X-ray coverage of ten objects, comprising eight candidates and two previously confirmed SNRs. We perform multi-frequency studies using additional data from the Magellanic Cloud Emission Line Survey (MCELS) to investigate their broadband emission and used Spitzer data to understand the environment in which the objects are evolving. We confirm seven of the eight candidates as bona-fide SNRs. We used a multi-frequency morphological study to determine the position and size of the remnants. We identify two new members of the class of evolved Fe-rich remnants in the Magellanic Clouds (MCs), several SNRs well into their Sedov-phase, one SNR likely projected towards a HII region, and a faint, evolved SNR with a hard X-ray core which could indicate a pulsar wind nebula. Overall, the seven newly confirmed SNRs represent a ~10% increase in the number of LMC remnants, bringing the total number to 71, and provide further insight into the fainter population of X-ray SNRs.