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RX J1643.7+3402 : a new bright cataclysmic variable

A. M. Mickaelian·S. K. Balayan·S. A. Ilovaisky·C. Chevalier·M. -P. Veron-Cetty·P. Veron
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Abstract

We report the discovery of a new bright (V$\sim$12.6) cataclysmic variable star identified with the ROSAT X-ray source RX J1643.7+3402. Spectroscopic and photometric observations show it to be a novalike variable sharing some of the characteristics of the SW Sex sub-class of novalike CVs. The spectroscopic period may be either 2\fh575 or 2\fh885, within the period "gap." A photometric modulation with a probable period of 2\fh595 and an amplitude of $\sim$ 0.1 mag in V is present on most nights and could be either a "positive" or a "negative" superhump modulation (depending on the exact spectroscopic period), indicating the presence of a precessing accretion disk in this system. Rapid variations of 0.1 to 0.2 mag amplitude in V repeat with a time scale of $\sim$ 15 min.

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A. M. Mickaelian, S. K. Balayan, S. A. Ilovaisky, C. Chevalier, M. -P. Veron-Cetty, P. Veron. 2001-08-23. RX J1643.7+3402 : a new bright cataclysmic variable. https://doi.org/10.1051/0004-6361%3A20011244

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