A new route to the solution of the type Ia supernova problem

Boaz Katz
July 7, 2017 - 12:15pm


The field of type Ia Supernovae (SNe) is in crisis. The classical idea that type Ia’s are the result of an explosion of near-Chandrasekhar mass White Dwarfs (WDs), which was never established to work, faces now strong observational and theoretical challenges as a dominant channel for type Ia’s across the observed brightness range. A zoo of suggested scenarios has replaced the old paradigm and a common view is emerging that several mechanisms (with the Chandrasekhar mass model often one of them) contribute signicantly to the population. This is in contrast with the continuous observed correlations found among the majority of type Ia's. We recently realised that direct collisions of typical WDs, which have been demonstrated to lead to successful explosions, may occur in multiple stellar systems at a sufficient rate to account for type Ia's. The collisions of the observed range of WDs result in the observed range of type Ia's brightness and thus may explain the entire population using one continuous model. Several simple robust observational tests have been already successfully conducted while significant challenges remain, including the demonstration of the required rate. Using recent progress in theoretical modeling tools and the accumulation of large observational data, I believe that powerful and robust tests for type Ia models can be conducted which will be conclusive for predictive scenarios and in particular for the promising collision model.