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arXiv · 2208.00053

Ignition of carbon burning from nuclear fission in compact stars

C. J. Horowitz
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Abstract

Type-Ia supernovae (SN Ia) are powerful stellar explosions that provide important distance indicators in cosmology. Recently, we proposed a new SN Ia mechanism that involves a nuclear fission chain reaction in an isolated white dwarf (WD) [PRL 126, 1311010]. The first solids that form as a WD starts to freeze are actinide rich and potentially support a fission chain reaction. In this letter we explore thermonuclear ignition from fission heating. We perform thermal diffusion simulations and find at high densities, above about 7x10^8 g/cm^3, that the fission heating can ignite carbon burning. This could produce a SN Ia or another kind of astrophysical transient.

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C. J. Horowitz. 2022-07-29. Ignition of carbon burning from nuclear fission in compact stars. https://doi.org/10.3847/2041-8213%2Fac8552

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