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 Infrared Spectrometer 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 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 , which our multiple observation epochs show varies over a timescale of months. The upper limit on the 70 μm 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 M moon . We conclude that the classification of disks into either protoplanetary or debris disks based on fractional infrared luminosity alone may be misleading.