Constraints on core-collapse supernova progenitors from correlations with H-alpha emission

TL;DR

This study investigates the correlation between core-collapse supernova types and recent star formation, revealing a sequence of increasing progenitor mass from type II to Ic, and providing constraints on their progenitor stars based on H-alpha emission associations.

Contribution

It provides observational evidence linking supernova types to progenitor mass ranges through analysis of their association with H-alpha emission in host galaxies.

Findings

Type II supernovae do not strongly trace star formation.

Type Ib supernovae show higher association with HII regions than Type II.

Type Ic supernovae accurately trace H-alpha emission, indicating higher progenitor masses.

Abstract

We present observational constraints on the nature of the different core-collapse supernova types through an investigation of the association of their explosion sites with recent star formation, as traced by H-alpha +[NII] line emission. We discuss results on the analysed data of the positions of 168 core-collapse supernovae with respect to the H-alpha emission within their host galaxies. From our analysis we find that overall the type II progenitor population does not trace the underlying star formation. Our results are consistent with a significant fraction of SNII arising from progenitor stars of less than 10 solar masses. We find that the supernovae of type Ib show a higher degree of association with HII regions than those of type II (without accurately tracing the emission), while the type Ic population accurately traces the H-alpha emission. This implies that the main core-collapse supernova types form a sequence of increasing progenitor mass, from the type II, to Ib and finally Ic. We find that the type IIn sub-class display a similar degree of association with the line emission to the overall SNII population, implying that at least the majority of these SNe do not arise from the most massive stars. We also find that the small number of SN `impostors' within our sample do not trace the star formation of their host galaxies, a result that would not be expected if these events arise from massive Luminous Blue Variable star progenitors.