PI: Steve B. Howell, NOAO, email@example.com
Address: KPNO, 950 N. Cherry Ave., Tucson, AZ 85726, US
CoI: Jay Holberg, University of Arizona
Title: Spectroscopy of the Unique White Dwarf BOKS 53836
Abstract: The newly discovered faint white dwarf BOKS 53836 shows a 6% (semi- amplitude) photometric modulation in its light curve which is difficult to explain. The source, discovered as a variable blue star, has most recently been observed at high cadence and with high photometric precision by the NASA Kepler mission. Initial spectroscopy shows that BOKS 53836 contains a hot white dwarf and may or may not be a binary. The Kepler light curve shows a stable 0.2556 day modulation whose shape is unique among white dwarf and binary optical light curves. The cause of the modulation in unknown and may be due to the white dwarf spin (possibly locked in synchronous orbit), irradiation of a close companion, geometric effects, a non-circular orbit, or some other phenomena. We propose to obtain time and spectral sampled red and blue spectroscopy of this white dwarf to elucidate the cause of the modulation. Our proposed observations will determine the true nature of the 6 hour modulation and thus provide a clearer picture of the white dwarf, its possible binary status, its evolution, and eventual fate.
National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360