Subarcsecond Imaging at 267 GH[CLC]z[/CLC] of a Young Binary System: Detection of a Dust Disk of Radius Less than 70 AU around T Tauri N

The young binary system T Tau was observed with the Owens Valley MillimeterArray at 267 GHz continuum and HCO+ J=3-2 emission at 0.8'' resolution, withthe JCMT-CSO single-baseline interferometer in 357 GHz continuum, and with theW. M. Keck Telescope at 4 micron. The 267 GHz emission is unresolved with aflux of 397 +/- 35 mJy, located close to the position of the optical star T TauN. An upper limit of 100 mJy is obtained toward the infrared companion T Tau S.The 357 GHz continuum emission is unresolved, with a flux of 1.35 +/- 0.68 Jy.HCO+ 3-2 was detected from a 2'' diameter core surrounding T Tau N and S. Bothstars are detected ar 4 micron, but there is no evidence of the radio source TTau R. We propose a model in which T Tau S is intrinsically similar to T Tau N,but is obscured by the outer parts of T Tau N's disk. A fit to the spectralenergy distribution (SED) between 21 cm and 1.22 micron is constructed on thisbasis. Adopting a r^-1 surface density distribution and an exponentiallytruncated edge, disk masses of 0.04 +/- 0.01 Msol and 6e-5 - 3e-3 Msol areinferred for T Tau N and S, respectively. A 0.005-0.03 Msol circumbinaryenvelope is also required to fit the millimeter to mid-infrared SED.Comment: ApJ Letters in press. 12 pages, incl. 2 figures. Uses AASTe