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Detection and measurement in the V-band of the white dwarf spin period in the January 2004 outburst of DO (YY) Draconis

David Boyd
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Abstract

A modulation in the V-band with period 527.84+/-1.81 sec and amplitude 0.023 magnitude, attributable to the spin of the magnetic white dwarf primary star, has been detected in 7.5 hours of V-band CCD photometry data recorded during the January 2004 outburst of the DQ Her type dwarf nova DO (YY) Draconis. This measurement is consistent with previous results for the white dwarf spin period based on X-ray and UV observations made with the Hubble Space Telescope, ROSAT and the Rossi X-ray Timing Explorer and appears to be the first independent determination of the spin period in the V-band. It is consistent with previous V-band observations in not showing a significant signal at the first harmonic of the spin period as seen in X-ray and UV data. Light output in the V-band peaks only once per rotation of the white dwarf rather than twice as seen in X-rays and UV. Concurrent observation at optical and X-ray wavelengths is needed to establish whether these two modulation behaviours occur at the same time during the outburst and to investigate the phase relationship between them. A coordinated observing campaign at a future outburst would help to advance our understanding of this system.

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David Boyd. 2004-09-14. Detection and measurement in the V-band of the white dwarf spin period in the January 2004 outburst of DO (YY) Draconis. https://arxiv.org/abs/astro-ph/0409349

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