AAVSO: American Association of Variable Star Observers

Light Curve Modeling and Secular Analyses of the Totally Eclipsing Overcontact Binary System V514 Draconis

Volume 51 number 1 (2023)

Download this article (pdf)

Kevin B. Alton
UnderOak Observatory, 70 Summit Avenue, Cedar Knolls, NJ 07927; kbalton@optonline.net
Franz-Josef Hambsch
Oude Bleken 12, Mol, 2400, Belgium; hambsch@telenet.be


Precise time-series CCD-derived photometric data (BVRc) were acquired from V514 Dra at Astrokolhoz Observatory in 2010 and Desert Blooms Observatory in 2022. An updated linear ephemeris was calculated from nine new times of minimum (ToM) produced from this study along with eight other values from the literature. Based on a quadratic fit of residuals from observed and predicted minimum times, secular analyses suggested the orbital period of V514 Dra may be slowly increasing at the rate of 0.0061 ± 0.0011 s · y–1. In addition, simultaneous modeling of new multi-bandpass (BVRc) light curve data was accomplished using the Wilson-Devinney (WD) code, revealing that V514 Dra is likely a W-subtype overcontact binary (OCB). Since a total eclipse is observed, a photometrically derived value for the mass ratio (qptm) with acceptable uncertainty could be determined which consequently provided preliminary estimates for selected physical and geometric elements of V514 Dra.