Models of H2 Fluorescence in the UV spectrum of the CTTS TW Hya
Abstract
Strong UV emission lines produced in accretion shocks of classical T Tauri stars significantly affect the chemistry of the circumstellar disks. The surface layers of the disk close to the star are analgous to a photo-dissociation region, only controlled by line rather than continuum emission. A broad Ly-α emission line incident on surface layers of the disk photoexcites the warm H2, producing Lyman-band H2 emission. We model this H2 fluorescence to determine the temperature and depth of the warm molecular layer. We compare these models to H2 fluorescence observed in the UV spectra of the CTTS TW Hya obtained with HST/STIS and FUSE. We discuss applications of this model, including disk truncation, disk height and disk dissipation.
See: Paper I: http://xxx.lanl.gov/abs/astro-ph/0201319, in ApJ 10 June 2002.- Publication:
-
SFChem 2002: Chemistry as a Diagnostic of Star Formation
- Pub Date:
- 2003
- Bibcode:
- 2003cdsf.conf..193H