Grain Growth and Global Structure of the Protoplanetary Disk Associated with the Mature Classical T Tauri Star, PDS 66
Abstract
We present ATCA interferometric observations of the old (13 Myr), nearby (86 pc) classical T Tauri star (CTTs), PDS 66. Unresolved 3 and 12 mm continuum emission is detected towards PDS 66, and upper limits are derived for the 3 and 6 cm flux densities. The mm data show a spectral slope flatter than that expected for ISM-sized dust particles, which is most likely a result of grain growth. We also present HST/NICMOS 1.1 μm PSF-subtracted coronagraphic imaging observations of PDS 66. The HST observations reveal a circumstellar region of dust scattering ~0.32% of the central starlight, declining in surface brightness as r-4.53. The disk is inclined 32+/-5° from face-on, and extends to a radius of 170 AU. These data are combined with published optical and longer-λ observations to make qualitative comparisons between the median Taurus and PDS 66 spectral energy distributions (SEDs). By comparing the near-infrared emission to a simple model, we det ermine that the location of the inner disk radius is consistent with being at dust sublimation (~1400 K at 0.1 AU). We place constraints on the mass surface density of the disk at 5 AU assuming a flat-disk model and find that it is probably too low to form gas giant planets according to current models. Despite the fact that PDS 66 is much older than a typical classical T Tauri star (<=5 Myr), its physical properties are not much different.
- Publication:
-
Exoplanets and Disks: Their Formation and Diversity
- Pub Date:
- August 2009
- DOI:
- 10.1063/1.3215810
- arXiv:
- arXiv:0903.3801
- Bibcode:
- 2009AIPC.1158..119C
- Keywords:
-
- 97.60.Lf;
- 95.75.Kk;
- 97.10.Fy;
- 98.35.Ac;
- Black holes;
- Interferometry;
- Circumstellar shells clouds and expanding envelopes;
- circumstellar masers;
- Origin formation evolution age and star formation;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 31 pages, 7 figures