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arXiv · astro-ph/9901295

WZ Sagittae as a DQ Herculis star

Jean-Pierre Lasota·Erik Kuulkers·Phil Charles
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Abstract

We argue that quiescent WZ Sge is a rapidly spinning magnetic rotator in which most of the matter transfered from the secondary is ejected from the system. Assuming that the observed 27.87 s oscillation period is due to the spinning white dwarf we propose that the other observed principal period of 28.96 s is a beat due to reprocessing of the rotating white dwarf beam on plasma blobs in Keplerian rotation at the outer disc rim. The weaker, transient, 29.69 s period is identified as a beat with the Keplerian period of the magnetosphere. WZ Sge evolves through a cycle of spin-up and spin-down phases. During the spin-down phase it is a DQ Her star, during the spin-up phase it should be a ER UMa star.

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Jean-Pierre Lasota, Erik Kuulkers, Phil Charles. 1999-01-21. WZ Sagittae as a DQ Herculis star. https://doi.org/10.1046/j.1365-8711.1999.02485.x

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