Revisiting the progenitor of the low-luminosity type II-plateau supernova, SN 2008bk

TL;DR

This study revisits the progenitor of SN 2008bk using updated models and data, concluding it was a cool red supergiant with a mass of 8-10 solar masses, consistent with low-luminosity Type IIP supernovae.

Contribution

The paper provides revised estimates of the progenitor's temperature, luminosity, and mass using new data and models, refining previous understandings of low-luminosity supernova progenitors.

Findings

Progenitor was a cool (~3500-3700 K) red supergiant.

Progenitor mass estimated at 8-10 solar masses.

No clear evidence of variability in the progenitor.

Abstract

The availability of updated model atmospheres for red supergiants and improvements in single and binary stellar evolution models, as well as previously unpublished data prompted us to revisit the progenitor of low-luminosity type II-Plateau supernova, SN 2008bk. Using mid-IR data in combination with dust models, we find that high temperature (4250-4500 K), high extinction (E(B-V)>0.7) solutions are incompatible with the data. We therefore favour a cool (~3500-3700 K) progenitor with a luminosity of log(L/Lsun)~4.53. Comparing with evolutionary tracks, we infer progenitor masses in the 8-10 Msun range in agreement with some previous studies. This mass is consistent with the observed pattern of low-luminosity Type IIP SNe coming from the explosion of RSGs at the lower extremum for core-collapse. We also present multi-epoch data of the progenitor, but do not find clear evidence of variability.