Active galactic nuclei are not responsible for systematics in the empirical properties of type Ia supernovae

Abstract

Despite being key cosmological anchors, the empirical properties of Type Ia supernovae (SNe Ia) remain subject to significant systematic uncertainties, the largest of which being their astrophysics and how this is linked to their environment. The relative importance of these uncertainties will grow as larger observational samples reduce statistical uncertainties. Here I explore if the presence of an active galactic nucleus (AGN) within a portion of SN Ia host galaxies could be one such systematic uncertainty. With the ZTF SNe Ia DR2 sample I find that, in the low redshift regime (z < 0.15), the presence of AGNs in some SN Ia hosts does not produce a significant systematic effect on their measured Hubble residuals.