Constraining Type Ia supernovae via their distances from spiral arms

TL;DR

This study analyzes the spatial distribution of Type Ia supernovae relative to spiral arms in host galaxies, revealing correlations between supernova properties, their locations, and the underlying galactic structures, which inform progenitor models.

Contribution

It introduces a novel analysis linking supernova distances from spiral arm shock fronts to their light curve decline rates, supporting progenitor age theories.

Findings

SNe Ia on spiral arms have slower decline rates than interarm SNe.

SN Ia distances from spiral arms correlate with galactocentric radius.

Significant correlation between decline rates and distances from shock fronts.

Abstract

We present an analysis of the distribution of 77 supernovae (SNe) Ia relative to spiral arms of their Sab-Scd host galaxies, using our original measurements of the SN distances from the nearby arms, and study their light curve decline rates ($\Delta m_{15}$). For the galaxies with prominent spiral arms, we show that the $\Delta m_{15}$ values of SNe Ia, which are located on the arms, are typically smaller (slower declining) than those of interarm SNe Ia (faster declining). We demonstrate that the SN Ia distances from the spiral arms and their galactocentric radii are correlated: before and after the average corotation radius, SNe Ia are located near the inner and outer edges (shock fronts) of spiral arms, respectively. For the first time, we find a significant correlation between the $\Delta m_{15}$ values and SN distances from the shock fronts of the arms (progenitor birthplace), which is explained in the frameworks of sub-Chandrasekhar-mass white dwarf explosion models and density wave theory, where, respectively, the $\Delta m_{15}$ parameter and SN distance from the shock front are appropriate progenitor population age (lifetime) indicators.