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arXiv · 1810.06146

The Origin of Magnetism in White Dwarfs

Lilia Ferrario
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Abstract

The absence of magnetic white dwarfs with a non-degenerate low-mass stellar companion in a wide binary is still very intriguing and at odds with the hypothesis that magnetic white dwarfs are the progenies of the magnetically peculiar Ap/Bp stars. On the other hand, we cannot resort to a process that impedes the generation of a strong magnetic field in the main or pre-main sequence progenitors of white dwarfs if they are in a multiple stellar system, because such a process would also prevent the formation of magnetic cataclysmic variables consisting of a magnetic white dwarf accreting mass from a low-mass companion. This is the reason why it has been proposed that fields in white dwarfs may be linked to their binarity and are generated through a dynamo mechanism during common envelope evolution.

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Lilia Ferrario. 2018-10-15. The Origin of Magnetism in White Dwarfs. https://arxiv.org/abs/1810.06146

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