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 12 CO (6-5) line. The observations trace the dynamics of warm (T≥60 K) and dense (≥10 5 cm −3 ) gas on a scale below 10″. The CO submillimeter emission probably originates in shocks where a stellar wind interacts with a high column density of molecular material close to the star. Additional 12 CO (3-2) and C 18 O (2-1) data show that the spatial distributions and line widths in T-Tau and HL-Tau are not consistent with Keplerian rotation or residual infall but can be explained by warm, dense, slowly outflowing material