Type Ia supernovae from stellar population of star formation deserts

Using a sample of nearby spiral galaxies hosting 185 supernovae (SNe) Ia, we perform a comparative analysis of the locations and light-curve (LC) decline rates (\(\Delta m_{15}\)) of normal and peculiar SNe Ia in the star formation deserts (SFDs) and beyond. By linking the LC decline rate and progenitor age, we show that the SFD phenomenon, where the star formation is suppressed by the bar evolution, gives a possibility to constrain the nature of SNe Ia. We demonstrate that the \(\Delta m_{15}\) of SN Ia and progenitor age can be related. We show, for the first time, that the SFDs contain mostly faster declining SNe Ia. For the galaxies without SFDs, the region within the bar radius, and outer disc contain mostly slower declining SNe Ia.