The Progenitors of Superluminous Type 1a Supernovae

Margot Fitz Axen, University of Texas at Austin

Type 1a Supernovae (SNe 1a) are common astrophysical transients and are used as cosmological distance probes because of the relative homogeneity of their light curves. While it is widely accepted that they originate from the thermonuclear explosion of a Carbon-Oxygen white dwarf (WD), the exact nature of their progenitors remains unknown. Recent observations have discovered a subclass of ’superluminous’ SNe 1a whose high luminosities suggest that they originate from the explosions of WDs with masses that exceed the Chandrasekhar mass limit, at which WD degeneracy pressure can no longer withstand gravity. Two models have been proposed to explain the progenitors of these explosions- a ‘magnetized WD’ model and a ‘WD merger’ model. To test the robustness of these models, we conduct a 1D numerical parameter survey of WD explosions using these models as initial conditions. We follow the explosions using the hydrodynamics code Castro and then use a radiative transport code to create light curves and spectra for the models. We compare the results of these simulations to observations and discuss which progenitor model is a better match.

Abstract Author(s): Margot Fitz Axen