Spatially and Spectrally Resolved Hydrogen Gas within 0.1 AU of T Tauri and Herbig Ae/Be Stars
Abstract
We present near-infrared observations of T Tauri and Herbig Ae/Be stars with a spatial resolution of a few milliarcseconds and a spectral resolution of ~2000. Our observations spatially resolve gas and dust in the inner regions of protoplanetary disks, and spectrally resolve broad-linewidth emission from the Brγ transition of hydrogen gas. We use the technique of spectro-astrometry to determine centroids of different velocity components of this gaseous emission at a precision orders of magnitude better than the angular resolution. In all sources, we find the gaseous emission to be more compact than or distributed on similar spatial scales to the dust emission. We attempt to fit the data with models including both dust and Brγ-emitting gas, and we consider both disk and infall/outflow morphologies for the gaseous matter. In most cases where we can distinguish between these two models, the data show a preference for infall/outflow models. In all cases, our data appear consistent with the presence of some gas at stellocentric radii of ~0.01 AU. Our findings support the hypothesis that Brγ emission generally traces magnetospherically driven accretion and/or outflows in young star/disk systems.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- August 2010
- DOI:
- 10.1088/0004-637X/718/2/774
- arXiv:
- arXiv:1006.1651
- Bibcode:
- 2010ApJ...718..774E
- Keywords:
-
- circumstellar matter;
- stars: individual: AS 205 AS 353 DG Tau DK Tau DR Tau MWC 275 MWC 480 MWC 758 MWC 863 MWC 1080 RY Tau RW Aur V1057 Cyg V1331 Cyg V2508 Oph;
- stars: pre-main sequence;
- techniques: interferometric;
- techniques: spectroscopic;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 48 pages, including 17 figures. Accepted for publication by ApJ