The 3D Structure of N132D in the LMC: A Late-Stage Young Supernova Remnant

TL;DR

This study maps the 3D structure of supernova remnant N132D in the LMC, revealing a ring-shaped ejecta structure, evidence of a bipolar explosion, and interactions with surrounding interstellar material.

Contribution

First detailed 3D reconstruction of N132D's ejecta, providing insights into its explosion geometry and interaction with the environment.

Findings

Ejecta form a ~12pc inclined ring

Remnant is approaching the end of reverse shock phase

Evidence of a polar jet and interaction with dense clouds

Abstract

We have used the Wide Field Spectrograph (WiFeS) on the 2.3m telescope at Siding Spring Observatory to map the [O III] 5007{\AA} dynamics of the young oxygen-rich supernova remnant N132D in the Large Magellanic Cloud. From the resultant data cube, we have been able to reconstruct the full 3D structure of the system of [O III] filaments. The majority of the ejecta form a ring of ~12pc in diameter inclined at an angle of 25 degrees to the line of sight. We conclude that SNR N132D is approaching the end of the reverse shock phase before entering the fully thermalized Sedov phase of evolution. We speculate that the ring of oxygen-rich material comes from ejecta in the equatorial plane of a bipolar explosion, and that the overall shape of the SNR is strongly influenced by the pre-supernova mass loss from the progenitor star. We find tantalizing evidence of a polar jet associated with a very fast oxygen-rich knot, and clear evidence that the central star has interacted with one or more dense clouds in the surrounding ISM.