Follow-up Studies of Five Cataclysmic Variable Candidates Discovered by LAMOST

Abstract

We report follow-up observations of five cataclysmic variable candidates from LAMOST published by Hou et al. (2020). LAMOST J024048.51+195226.9 is the most unusual of the five; an early-M type secondary star contributes strongly to its spectrum, and its spectral and photometric behavior are strikingly reminiscent of the hitherto-unique propeller system AE Aqr. We confirm that a 7.34-hr period discovered in the Catalina survey data (Drake et al. 2014) is orbital. Another object, LAMOST J204305.95+341340.6 appears to be a near twin of the novalike variable V795 Her, with an orbital period in the so-called 2-3 hour "gap". LAMOST J035913.61+405035.0 is evidently an eclipsing, weakly-outbursting dwarf nova with a 5.48-hr period. Our spectrum of LAMOST J090150.09+375444.3 is dominated by a late-type secondary and shows weak, narrow Balmer emission moving in phase with the absorption lines, but at lower amplitude; we do not see the HeII 4686 emission evident in the published discovery spectrum. We again confirm that a period from the Catalina data, in this case 6.80 hr, is orbital. LAMOST J033940.98+414805.7 yields a radial-velocity period of 3.54 hr, and its spectrum appears to be typical of novalike variables in this period range. The spectroscopically-selected sample from LAMOST evidently includes some interesting cataclysmic variables that have been unrecognized until now, apparently because of the relatively modest range of their photometric variations.

Astronomical Journal, in press

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Cited by in corpus (7)

• The Orbital Period vs. Absolute Magnitude Relationship of Intermediate Polars: Implications for Low States and Outbursts
• Radio and optical observations of the possible AE Aqr twin, LAMOST J024048.51+195226.9
• Radio detections of two unusual cataclysmic variables in the VLA Sky Survey
• Unveiling the white dwarf in J191213.72-441045.1 through ultraviolet observations
• Optical detection of the rapidly spinning white dwarf in V1460 Her
• VLA Observations of the AE Aqr-type Cataclysmic Variable LAMOST J024048.51+195226.9
• Exploration of faint X-ray and radio sources in the massive globular cluster M14: A UV-bright counterpart to Nova Ophiuchus 1938