Constraints on Shallow 56Ni from the Early Lightcurves of Type Ia Supernovae

Understand

Ongoing transient surveys are presenting an unprecedented account of the rising lightcurves of Type Ia supernovae (SNe Ia).

• This early emission probes the shallowest layers of the exploding white dwarf, which can provide constraints on the progenitor star and the properties of the explosive burning.
• We use semi-analytic models of radioactively-powered rising lightcurves to analyze these observations.
• As we have summarized in previous work, the main limiting factor in determining the surface distribution of 56Ni is the lack of an unambiguously identified time of explosion, as would be provided by detection of shock breakout or shock-heated cooling.