Photometric analysis of the overcontact binary CW Cas

Journal Article · Sat Nov 01 04:00:00 EDT 2014 · Astronomical Journal (New York, N.Y. Online)

DOI:https://doi.org/10.1088/0004-6256/148/5/95· OSTI ID:22342222

Wang, J. J.; Qian, S. B.; He, J. J.; Li, L. J.

New CCD photometric observations of overcontact binary CW Cas were carried out in 2004 and 2011. In particular, the light curve obtained in 2004 shows a remarkable O'Connell effect. Compared with light curves in different observing seasons, variations were found. These variations can be explained by dark spot activities on the surface of at least one component. Using the Wilson-Devinney code with a spot model, we find that the photometric solutions confirm CW Cas is a shallow W-subtype overcontact binary with a spotted massive component. Our new determined times of minimum light together with the others published in the literature were analyzed to find a change of orbital period. From the O – C curves, the period of the system shows a cyclic period change (P {sub 3} = 69.9 yr, A {sub 3} = 0.03196 days) superposed on the linear increase. The cyclic variation, if explained as the light-travel time effect, reveals the presence of a tertiary companion.

• OSTI ID: 22342222
• Journal Information: Astronomical Journal (New York, N.Y. Online), Journal Name: Astronomical Journal (New York, N.Y. Online) Journal Issue: 5 Vol. 148; ISSN 1538-3881
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
BINARY STARS
CHARGE-COUPLED DEVICES
COMPARATIVE EVALUATIONS
ECLIPSE
MATHEMATICAL SOLUTIONS
STARS
SURFACES
VARIATIONS
VISIBLE RADIATION