Integral field spectroscopy of supernova explosion sites: constraining mass and metallicity of the progenitors - I. Type Ib and Ic supernovae

TL;DR

This study uses integral field spectroscopy to analyze supernova explosion sites, determining progenitor star metallicity and mass, revealing differences between Type Ib and Ic supernovae, and supporting binary interaction scenarios.

Contribution

It introduces a method combining spatial and spectral data to estimate progenitor metallicity and mass for Type Ib/c supernovae, highlighting the role of binary systems.

Findings

SN Ic sites are more metal-rich and younger than SN Ib sites.

SN Ic progenitors are more massive than SN Ib progenitors.

Some progenitors may be less than 25 solar masses, indicating binary evolution.

Abstract

Integral field spectroscopy of 11 type-Ib/c supernova explosion sites in nearby galaxies has been obtained using UH88/SNIFS and Gemini-N/GMOS. The use of integral field spectroscopy enables us to obtain both spatial and spectral information of the explosion site, allowing the identification of the parent stellar population of the supernova progenitor star. The spectrum of the parent population provides metallicity determination via strong-line method and age estimation obtained via comparison with simple stellar population (SSP) models. We adopt this information as the metallicity and age of the supernova progenitor, under the assumption that it was coeval with the parent stellar population. The age of the star corresponds to its lifetime, which in turn gives the estimate of its initial mass. With this method we were able to determine both the metallicity and initial (ZAMS) mass of the progenitor stars of the type Ib and Ic supernovae. We found that on average SN Ic explosion sites are more metal-rich and younger than SN Ib sites. The initial mass of the progenitors derived from parent stellar population age suggests that SN Ic have more massive progenitors than SN Ib. In addition, we also found indication that some of our SN progenitors are less massive than ~25 Msun, indicating that they may have been stars in a close binary system that have lost their outer envelope via binary interactions to produce Ib/c supernovae, instead of single Wolf-Rayet stars. These findings support the current suggestions that both binary and single progenitor channels are in effect in producing type Ib/c supernovae. This work also demonstrates the power of integral field spectroscopy in investigating supernova environments and active star forming regions.