Variability of the Spin Period of the White Dwarf in the Intermediate Polar V405 Aur: Low-Mass Third Body or Precession ?

V. V. Breus; I. L. Andronov; P. Dubovsky; S. V. Kolesnikov; E. A. Zhuzhulina; T. Hegedus; P. Beringer; K. Petrik; J. W. Robertson; A. V. Ryabov; I. Kudzej; N. M. Shakhovskoy

arXiv · 1306.4665

Variability of the Spin Period of the White Dwarf in the Intermediate Polar V405 Aur: Low-Mass Third Body or Precession ?

V. V. Breus·I. L. Andronov·P. Dubovsky·S. V. Kolesnikov·E. A. Zhuzhulina·T. Hegedus·P. Beringer·K. Petrik·J. W. Robertson·A. V. Ryabov·I. Kudzej·N. M. Shakhovskoy

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Abstract

We present the results of photometric CCD observations of the magnetic cataclysmic variable V405 Aurigae (RX J0558.0+5353 = 1RXS J055800.7+535358) obtained using different instruments. We analysed variability of the spin period of the white dwarf in the V405 Aur (RX J0558.0+5353) system using our observations and previously published maxima timings. The spin period of the system in 2010-2012 is $P=545.4558163(94)$s. As we have gaps in observational data, we present 2 hypotheses of the spin period variability of this system - a cubic ephemeris which may be interpreted by a precession of the magnetic white dwarf or a periodic change with a period of 6.2 years and semi-amplitude of $17.2\pm1.8$ sec. The periodic variations may be interpreted by a light-time effect caused by a low-mass star ($M_3\ge0.09M_\odot$). In this case, the system belongs to a rare class of cataclysmic variables with a third body.

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V. V. Breus, I. L. Andronov, P. Dubovsky, S. V. Kolesnikov, E. A. Zhuzhulina, T. Hegedus, P. Beringer, K. Petrik, J. W. Robertson, A. V. Ryabov, I. Kudzej, N. M. Shakhovskoy. 2013-06-16. Variability of the Spin Period of the White Dwarf in the Intermediate Polar V405 Aur: Low-Mass Third Body or Precession ?. https://arxiv.org/abs/1306.4665

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