The Discovery of a Debris Disk Around the DAV White Dwarf PG 1541+651
  To search for circumstellar disks around evolved stars, we targeted roughly
100 DA white dwarfs from the Palomar Green survey with the Peters Automated
Infrared Imaging Telescope (PAIRITEL). Here we report the discovery of a debris
disk around one of these targets, the pulsating white dwarf PG 1541+651 (KX
Draconis, hereafter PG1541). We detect a significant flux excess around PG1541
in the K-band. Follow-up near-infrared spectroscopic observations obtained at
the NASA Infrared Telescope Facility (IRTF) and photometric observations with
the warm Spitzer Space Telescope confirm the presence of a warm debris disk
within 0.13-0.36 Rsun (11-32x the stellar radius) at an inclination angle of
60deg. At Teff = 11880 K, PG1541 is almost a twin of the DAV white dwarf
G29-38, which also hosts a debris disk. All previously known dusty white dwarfs
are of the DAZ/DBZ spectral type due to accretion of metals from the disk.
High-resolution optical spectroscopy is needed to search for metal absorption
lines in PG1541 and to constrain the accretion rate from the disk. PG1541 is
only 55 pc away from the Sun and the discovery of its disk in our survey
demonstrates that our knowledge of the nearby dusty white dwarf population is
far from complete.
