SUBMILLIMETER CO OBSERVATIONS OF WARM GAS AROUND T-TAURI STARS

We report the first observations of T Tauri stars (T-, HL-, DG-, RY-, and GG-Tau) in the (CO)-C-12 (6-5) line. The observations trace the dy namics of warm (T greater-than-or-equal-to 60 K) and dense (greater-th an-or-equal-to 10(5) cm-3) gas on a scale below 10''. The CO submillim eter emission probably originates in shocks where a stellar wind inter acts with a high column density of molecular material close to the sta r. Additional (CO)-C-12 (3-2) and (CO)-O-18 (2-1) data show that the s patial distributions and line widths in T-Tau and HL-Tau are not consi stent with Keplerian rotation or residual infall but can be explained by warm, dense, slowly outflowing material. We also conclude that the dust associated with the warm molecular outflow could account for a su bstantial fraction of T-Tau's far-infrared continuum emission.