1 research outputs found
HD 101088, An Accreting 14 AU Binary in Lower Centaurus Crux With Very Little Circumstellar Dust
We present high resolution (R=55,000) optical spectra obtained with MIKE on
the 6.5 m Magellan Clay Telescope as well as Spitzer MIPS photometry and IRS
low resolution (R~60) spectroscopy of the close (14 AU separation) binary, HD
101088, a member of the ~12 Myr old southern region of the Lower Centaurus Crux
(LCC) subgroup of the Scorpius-Centaurus OB association. We find that the
primary and/or secondary is accreting from a tenuous circumprimary and/or
circumsecondary disk despite the apparent lack of a massive circumbinary disk.
We estimate a lower limit to the accretion rate of > 1x10^-9 solar masses per
year, which our multiple observation epochs show varies over a timescale of
months. The upper limit on the 70 micron flux allows us to place an upper limit
on the mass of dust grains smaller than several microns present in a
circumbinary disk of 0.16 moon masses. We conclude that the classification of
disks into either protoplanetary or debris disks based on fractional infrared
luminosity alone may be misleading.Comment: 8 pages, 2 figures, ApJ accepte