Improved Constraints on Type Ia Supernova Host Galaxy Properties using Multi-Wavelength Photometry and their Correlations with Supernova Properties

TL;DR

This study enhances the estimation of host galaxy properties for Type Ia supernovae by integrating multi-wavelength photometry, revealing correlations between galaxy age, mass, and supernova brightness after standard corrections.

Contribution

It introduces improved methods for estimating host galaxy properties using UV, optical, and near-IR data, and identifies new correlations with supernova brightness.

Findings

Older host galaxies tend to host brighter SNe Ia after corrections.

More massive galaxies are associated with brighter SNe Ia post-correction.

Evidence of correlations at 1.9σ and 3.0σ confidence levels.

Abstract

We improve estimates of stellar mass and mass-weighted average age of Type Ia supernova (SN Ia) host galaxies by combining UV and near-IR photometry with optical photometry in our analysis. Using 206 SNe Ia drawn from the full three-year SDSS-II Supernova Survey (median redshift of z {\approx} 0.2) and multi-wavelength host-galaxy photometry from SDSS, GALEX, and UKIDSS, we present evidence of a correlation (1.9{\sigma} confidence level) between the residuals of SNe Ia about the best-fit Hubble relation and the mass-weighted average age of their host galaxies. The trend is such that older galaxies host SNe Ia that are brighter than average after standard light-curve corrections are made. We also confirm, at the 3.0{\sigma} level, the trend seen by previous studies that more massive galaxies often host brighter SNe Ia after light-curve correction.