Reconsidering photometric estimation of local star formation environment and its correlation with Type Ia Supernova luminosity

Understand

Recent studies on the environmental dependence of Type Ia supernova (SN Ia) luminosity focus on the local environment where the SN exploded, considering that this is more directly linked to the SN progenitors.

• However, there is a debate about the local environmental, specifically local star formation rate (SFR), dependence of the SN Ia luminosity.
• A recent study claims that the dependence is insignificant ($0.051 \pm 0.020$ mag; $2.6\sigma$), based on the local SFR measurement by fitting local $ugrizy$ photometry data.
• However, we find that this photometric local SFR measurement is inaccurate.