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Time-Resolved Photometry of GK Per during the 1996 Outburst

D. Nogami·T. Kato·H. Baba
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Abstract

GK Per is a unique cataclysmic variable star which has showed a nova explosion as well as dwarf nova-type outbursts, and has the intermediate-polar nature. We carried out V-band time-resolved photometry and B-band monitoring during the 1996 outburst. This outburst lasted about 60 d and is divided into three parts: the slow rise branch for 35 d, the gradual decay branch with a decay rate of 20.0 d/mag for ~16 d, and the rapid decline branch with a rate of 5.6 d/mag for ~10 d. The $B-V$ color became bluest (B-V~0.18) about 10 d before the outburst maximum, which supports an idea that the outburst in GK Per is of the inside-out type. The spin pulse, 440-s quasi periodic oscillations (QPOs), and ~5,000-s QPOs were detected in our light curve, as previously seen in X-ray and optical observations. In addition, we report the discovery of ~300-s periodicity, which is shorter than the spin period.

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D. Nogami, T. Kato, H. Baba. 2002-09-20. Time-Resolved Photometry of GK Per during the 1996 Outburst. https://doi.org/10.1093/pasj%2F54.6.987

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