Five Supernova Survey Galaxies in the Southern Hemisphere: Supernova Ia Rates

TL;DR

This study analyzes supernova rates in 3838 southern hemisphere galaxies, revealing dependencies on galaxy morphology and star-formation activity, and suggesting a significant fraction of Type Ia supernovae originate from young stellar populations.

Contribution

It provides the first comprehensive supernova rate analysis normalized to galaxy luminosity and mass in the southern hemisphere, highlighting the link to galaxy properties.

Findings

Type Ia supernova rates depend on galaxy morphology and colors.

At least 15% of Ia events in spirals originate from young stars.

Supernova rates show no correlation with nuclear activity or environment.

Abstract

Based on the database of 56 supernovae (SNe) events discovered in 3838 galaxies of the southern hemisphere, we compute the rate of SNe of different types along the Hubble sequence normalized to the optical and near-infrared (NIR) luminosities as well as to the stellar mass of the galaxies. We find that the rates of Type Ia SNe show a dependence on both morphology and colors of the galaxies, and therefore, on the star-formation activity. The rate of SNe Ia can be explained by assuming that at least 15% of Ia events in spiral galaxies originate in relatively young stellar populations. We also find that the rates show no modulation with nuclear activity or environment.