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arXiv · 1609.02508

A Model of White Dwarf Pulsar AR Scorpii

Jin-Jun Geng·Bing Zhang·Yong-Feng Huang
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Abstract

A 3.56-hour white dwarf (WD) - M dwarf (MD) close binary system, AR Scorpii, was recently reported to show pulsating emission in radio, IR, optical, and UV, with a 1.97-minute period, which suggests the existence of a WD with a rotation period of 1.95 minutes. We propose a model to explain the temporal and spectral characteristics of the system. The WD is a nearly perpendicular rotator, with both open field line beams sweeping the MD stellar wind periodically. A bow shock propagating into the stellar wind accelerates electrons in the wind. Synchrotron radiation of these shocked electrons can naturally account for the broad-band (from radio to X-rays) spectral energy distribution of the system.

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Jin-Jun Geng, Bing Zhang, Yong-Feng Huang. 2016-09-08. A Model of White Dwarf Pulsar AR Scorpii. https://doi.org/10.3847/2041-8205/831/1/l10

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