Physical parameters of the Keplerian protoplanetary disk of DM Tau

Stéphane Guilloteau , Anne Dutrey
IRAM, 300 Rue de la Piscine, F-38406 Saint Martin d'Hères, France
Abstract:
vspace3ex We present high sensitivity 3'' aperture synthesis images of the DM Tau protoplanetary disk in the CO J=1-0 line. The images unambiguously reveal that the disk is rotating around the central star. To model the observations in terms of a rotating disk in hydrostatic equilibrium, we have developped a fitting procedure which allows derivation of the disk parameters and their errors. Dependencies among the disk parameters are discussed in detail. The disk is large, with an outer radius of 850 AU. We find that the rotation curve is essentially Keplerian, at least up to 600 AU. The stellar mass derived from the rotation curve is . The intrinsic local velocity dispersion in the disk is found to be essentially thermal, with a turbulent component of less than 30 % of the thermal width. Parameters derived from this observation are used to confirm the molecular abundances and depletion factors estimated for several simple organic molecules by Dutrey et al (1997) for DMTau.

Astron. Astrophys. in press. Preprints: guillote@iram.fr guillote/PRE/ms7873.ps.gz">