Gas evolution in protoplanetary disks

W. F. Thi, E.F. van Dishoeck, G.J. van Zadelhoff, G. A. Blake, V. Mannings, A. I. Sargent, J. Horn, E. E. Becklin, M.E. van den Ancker, A. Natta
2004 Symposium - International astronomical union  
We present the results of a study of the evolution of the gas and dust in disks around T Tauri, Herbig Ae and Vega-like stars. We observed the two lowest rotational lines of H2with the ISO-SWS as well as12CO 3–2 and13CO 3–2 with the JCMT, and CO 6–5 with the CSO. The H2lines trace the warm (∽ 100 K) inner region whereas the CO lines probe the colder outer disks. Substantial amounts of H2have been detected toward T Tauri and Herbig Ae stars, and, surprisingly, also around three Vega-like objects
more » ... (49 Cet, HD 135344 and β Pictoris). In contrast with previous conclusions derived from CO data, a significant mass of warm gas is found to persist up to ages of several tens of Myrs, suggesting that slow formation of gas-rich giant planets is possible.
doi:10.1017/s0074180900218317 fatcat:2kuh2kc7yvcgjp2b7j7oehqssm