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arXiv · 2103.02122

Actinide crystallization and fission reactions in cooling white dwarf stars

C. J. Horowitz·M. E. Caplan
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Abstract

The first solids that form as a cooling white dwarf (WD) starts to crystallize are expected to be greatly enriched in actinides. This is because the melting points of WD matter scale as $Z^{5/3}$ and actinides have the largest charge $Z$. We estimate that the solids may be so enriched in actinides that they could support a fission chain reaction. This reaction could ignite carbon burning and lead to the explosion of an isolated WD in a thermonuclear supernova (SN Ia). Our mechanism could potentially explain SN Ia with sub-Chandrasekhar ejecta masses and short delay times.

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C. J. Horowitz, M. E. Caplan. 2021-03-03. Actinide crystallization and fission reactions in cooling white dwarf stars. https://doi.org/10.1103/physrevlett.126.131101

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