Characterising the environments of supernovae with MUSE

TL;DR

This study uses MUSE integral field spectroscopy to analyze the environments of 11 supernovae in 6 nearby galaxies, characterizing local stellar populations and host galaxy properties to better understand supernova progenitors.

Contribution

It introduces a method to map and analyze supernova environments within host galaxies using HII region properties from MUSE data, enabling detailed progenitor environment studies.

Findings

Supernovae are located in diverse host galaxy environments.

HII region properties vary significantly within host galaxies.

The method allows for detailed comparison of supernova sites with overall galaxy properties.

Abstract

We present a statistical analysis of the environments of 11 supernovae (SNe) which occurred in 6 nearby galaxies (z $\lesssim$ 0.016). All galaxies were observed with MUSE, the high spatial resolution integral field spectrograph mounted to the 8m VLT UT4. These data enable us to map the full spatial extent of host galaxies up to $\sim$3 effective radii. In this way, not only can one characterise the specific host environment of each SN, one can compare their properties with stellar populations within the full range of other environments within the host. We present a method that consists of selecting all HII regions found within host galaxies from 2D extinction-corrected H$\alpha$ emission maps. These regions are then characterised in terms of their H$\alpha$ equivalent widths, star formation rates, and oxygen abundances. Identifying HII regions spatially coincident with SN explosion sites, we are thus able to determine where within the distributions of host galaxy e.g. metallicities and ages each SN is found, thus providing new constraints on SN progenitor properties. This initial pilot study using MUSE opens the way for a revolution in SN environment studies where we are now able to study multiple environment SN progenitor dependencies using a single instrument and single pointing.