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arXiv · 1611.07653

Thermal X-ray emission from massive, fast rotating, highly magnetized white dwarfs

D. L. Caceres·S. M. de Carvalho·J. G. Coelho·R. C. R. de Lima·Jorge A. Rueda
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Abstract

There is solid observational evidence on the existence of massive, $M\sim 1~M_\odot$, highly magnetized white dwarfs (WDs) with surface magnetic fields up to $B\sim 10^9$ G. We show that, if in addition to these features, the star is fast rotating, it can become a rotation-powered pulsar-like WD and emit detectable high-energy radiation. We infer the values of the structure parameters (mass, radius, moment of inertia), magnetic field, rotation period and spin-down rates of a WD pulsar death-line. We show that WDs above the death-line emit blackbody radiation in the soft X-ray band via the magnetic polar cap heating by back flowing pair-created particle bombardment and discuss as an example the X-ray emission of soft gamma-repeaters and anomalous X-ray pulsars within the WD model.

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D. L. Caceres, S. M. de Carvalho, J. G. Coelho, R. C. R. de Lima, Jorge A. Rueda. 2016-11-23. Thermal X-ray emission from massive, fast rotating, highly magnetized white dwarfs. https://doi.org/10.1093/mnras%2Fstw3047

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