Possible Contribution of Magnetized White Dwarf Binaries to Type Ia Supernova Populations

Abstract

The evolution of an accreting white dwarf (WD) with strong magnetic field toward a type Ia supernova (SN Ia) may differ from the classical single-degenerate (SD) channel. In this paper, we perform binary population synthesis (BPS) simulations for the SD channel with a main-sequence (MS) companion, including the strongly magnetized WD accretion. Under a reasonable assumption that the fraction of such systems is $\sim 15$%, the resulting delay time distribution (DTD) roughly follows the $t^{-1}$ power-law distribution. Within the (WD/MS) SD channel, the contribution from the highly magnetized WD is estimated to be comparable to that from the classical, non-magnetized WD channel. The contribution of the SD channel toward SNe Ia can be at least $\sim 30$% among the whole SN Ia population. We suggest that the SNe Ia resulting from the highly-magnetized WD systems would not share observational properties expected for the classical SD channel; for every (potentially peculiar) SN observationally associated with the SD channel, we expect a comparable number of the `hidden' SD population in the normal class.