Friday

The new era of time-domain surveys has led to an increase in the number of Type Ia supernovae caught soon after explosion, which has brought to light the significant variation in the early time light curves. One major driving factor for early time evolution is the distribution of nickel in the ejecta, which can differ considerably as a result of different explosion mechanisms.
We performed an analysis of the nickel distribution of the largest, low bias sample of SNe Ia to date provided by the Zwicky Transient Facility. We model the light curves with the TURTLS model grid containing light curves of Chandrasekhar mass explosions.
We find that the light curves of 66 per cent of objects can be reproduced with Chandrasekhar-mass explosion models, and the sample is dominated by objects with highly extended distributions of nickel.
Furthermore, several SNe Ia have shown "bumps" in their early light curves, which could help us unravel their progenitor scenarios. For this reason, we developed a method of identifying potential early excesses and identify 11 per cent of our sample with a flux excess in the g-band. These objects are found in predominantly low-mass galaxies, and have generally broad light curves, which could have implications for their progenitor scenarios.