Photometric Analyses and Spectral Identification of the Early-Spectral Type W UMa Contact Binary V444 Andromedae

摘要

Presented here are the first precision UBVR_cI_c light curves,synthetic light curve solutions, a period study, and spectrum for V444 Andromedae, an F0V contact W UMa binary. Observations were taken with the Lowell Observatory 0.81-m reflector during 28 through 30 September 2012. From our period study we determined a linear ephemeris showing that the period has been stable over the past 9.6 years (~7,500 orbits). The period during this interval is 0.46877942 d. After a q-search, the lowest residual mass ratio was found to be 0.48 with a Roche-lobe fill-out of nearly 51%. Despite its rather high temperature, 7,300 K, two magnetic spots were modeled on the primary component, a 10° radius equatorial dark spot with a T-factor of 0.88 and a 23° radius near-polar hot spot of T-factor 1.10. The component temperature difference was only ~80K. These parameters point to a mature, early type, W UMa binary.