Progenitor Mass Distribution of Core-Collapse Supernova Remnants in Our Galaxy and Magellanic Clouds based on Elemental Abundances

TL;DR

This study estimates the progenitor mass distribution of core-collapse supernova remnants in our galaxy and the Magellanic Clouds using elemental abundance ratios, finding a distribution consistent with the Salpeter initial mass function after revising previous estimates.

Contribution

It introduces a new method relying on Fe/Si ratios to estimate progenitor masses, improving accuracy over previous abundance-based methods.

Findings

Progenitor mass distribution is inconsistent with standard IMFs using previous methods.

Fe/Si ratio provides a more reliable estimate of progenitor mass.

Revised distribution aligns with the Salpeter initial mass function.

Abstract

We investigate a progenitor mass distribution of core-collapse supernova remnants (CCSNRs) in our Galaxy and the Large and Small Magellanic Clouds, for the first time. We count the number of CCSNRs in three mass ranges divided by the zero-age main-sequence mass, $M_{\rm ZAMS}$; A: $M_{\rm ZAMS} < 15\ {\rm M}_\odot$, B: $15\ {\rm M}_\odot < M_{\rm ZAMS} < 22.5\ {\rm M}_\odot$, C: $M_{\rm ZAMS} > 22.5\ {\rm M}_\odot$. Simple compilation of progenitor masses in the literature yields a progenitor mass distribution of $f_{\rm A}: f_{\rm B}: f_{\rm C} =0.24:0.28:0.48$, where $f$ is the number fraction of the progenitors. The distribution is inconsistent with any standard initial mass functions. We notice, however, that previous mass estimates are subject to large systematic uncertainties because most of the relative abundances (X/Si) are not really good probe for the progenitor masses. Instead, we propose to rely only on the Fe/Si ratio which is sensitive to the CO core mass ($M_{\rm COcore}$) and $M_{\rm ZAMS}$. Comparing Fe/Si ratios in SNRs in the literature with the newest theoretical model, we estimate 33 $M_{\rm COcore}$ and $M_{\rm ZAMS}$, leading to a revised progenitor mass distribution of $f_{\rm A}: f_{\rm B}: f_{\rm C} = 0.47: 0.32 : 0.21$. This is consistent with the standard Salpeter initial mass function. However, the relation between $M_{\rm COcore}$ and $M_{\rm ZAMS}$ could be affected by binary evolution, which is not taken into account in this study and should be considered in the future work to derive a better progenitor mass distribution estimate.