The observed phase space of mass-loss history from massive stars based on radio observations of a large supernova sample

TL;DR

This study uses radio observations of 325 supernovae to analyze the circumstellar material and mass-loss rates of massive star progenitors, revealing discrepancies and constraining typical mass-loss rates in the last millennium before explosion.

Contribution

It provides a large statistical analysis of mass-loss rates from massive stars using radio data, constraining previously uncertain ranges and highlighting discrepancies between detected and non-detected supernovae.

Findings

Discrepancy between mass-loss rates from radio-detected and non-detected SNe.

Ruled out mass-loss rates of 2×10⁻⁶ to 10⁻⁴ M☉/yr for 80% of type II SNe progenitors.

Excluded certain mass-loss rate ranges for red supergiants in about 50% of type II SNe progenitors.

Abstract

In this work we study the circumstellar material (CSM) around massive stars, and the mass-loss rates depositing this CSM, using a large sample of radio observations of 325 core-collapse supernovae (CCSNe; only $\sim 22 \%$ of them being detected). This sample comprises both archival data and our new observations of 99 CCSNe conducted with the AMI-LA radio array in a systematic approach devised to constrain the mass-loss at different stages of stellar evolution. In the SN-CSM interaction model, observing the peak of the radio emission of a SN provides the CSM density at a given radius (and therefore mass-loss rate that deposited this CSM). On the other hand, limits on the radio emission, and/or on the peak of the radio emission provide a region in the CSM phase space that can be ruled out. Our analysis shows discrepancy between the values of mass-loss rates derived from radio-detected and radio-non-detected SNe. Furthermore, we rule out mass-loss rates in the range of $2 \times 10^{-6} - 10^{-4} \, \rm M_{\odot} \, yr^{-1}$ for different epochs during the last 1000 years before the explosion (assuming wind velocity of $10 \, \rm km \, s^{-1}$) for the progenitors of $\sim 80\%$ of the type II SNe in our sample. In addition, we rule out the ranges of mass-loss rates suggested for red supergiants for $\sim 50 \%$ of the progenitors of type II SNe in our sample. We emphasize here that these results take a step forward in constraining mass-loss in winds from a statistical point of view.