http://arxiv.org/abs/1501.07837
At intervals as short as ten thousand years, each white dwarf (WD) passes within a solar radius of a planetoid, i.e., a comet, asteroid, or planet. Gravitational tidal forces tear the planetoid apart; its metal-rich debris falls onto the WD, enriching the atmosphere. A third of WDs exhibit atmospheric “pollution”. For roughly every hundred planetoid disruptions, a planetoid collides with a WD. We simulate a small number of collisions, in which “death-by-dynamics” refers to the fate of the planetoid. We also compute the energies and likely durations of a broad sample of collision events, and identify detection strategies at optical and X-ray wavelengths. Collisions with the most massive planetoids can be detected in external galaxies. Some may trigger nuclear burning. If one in $\sim 10^7-10^8$ of WD-planetoid collisions creates the conditions needed for a Type Ia supernova (SN~Ia), “death-by-dynamics” would also refer to the fate of the WD, and could provide a novel channel for the production of SN~Ia. We consider the circumstances under which the rate of SNe~Ia can be increased by interactions with planetoids.
R. Stefano, R. Fisher, J. Guillochon, et. al.
Mon, 2 Feb 15
13/49
Comments: 15 pages, 1 figure, 1 table