Spectroscopically Identified Cataclysmic Variables from the LAMOST Survey. II. Period Estimates

Abstract We examine a sample of 340 cataclysmic variables (CVs) from the latest data release Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) survey, along with 18 objects that are newly classified as CVs. In this paper, we focus on investigating photometric behaviors these CVs using time-domain surveys. The orbital periods three new and five previously known determined long-term light curves displaying eclipses or ellipsoidal variations, and/or time-resolved spectra LAMOST. For another 16 measured periods, it is more reliable to obtain consistent different surveys, derived single-site still questionable. Follow-up observations needed confirm whether have physical meanings orbital-related. our sample, find most longer above 2 ∼ 3 hr gap. Besides period estimates, also carry out separate detailed analysis some valuable CVs, in terms spectral characteristics subtype determination. Finally, discuss observational properties including distributions absolute magnitudes, statistical each subclass addition, pick six non-CV systems, illumination-effect binaries, well one hot subdwarf, came across when searching for investigate their based data.