On the ionized regions associated with T Tauri stars.
Abstract
Upper limits to the amounts of ionized gas in extended regions (r equal to or greater than 10 to the 14th cm) around T Tau stars are derived from upper limits to the 10.5-GHz, 8.0-GHz, and 5.0-GHz continuum flux densities. The star T Tau itself was marginally detected. The implications of other recent observations related to physical processes in the extended circumstellar environment of T Tau are briefly discussed, with emphasis on the possible role that ionizing radiation from a high-velocity shock may have in the excitation of gas outside the shocked region. It is suggested that ultraviolet radiation from 200-km/s shocks near the star may be responsible for pumping the v = 1-0 S(1) infrared transition of H2 in T Tau and that soft X-rays from the shocks partially ionize the surrounding region, as suggested by the anomalous forbidden O I 6300-A to H-alpha line ratio.
- Publication:
-
The Astronomical Journal
- Pub Date:
- November 1979
- DOI:
- 10.1086/112599
- Bibcode:
- 1979AJ.....84.1709M
- Keywords:
-
- Interstellar Gas;
- Ionized Gases;
- Ionizing Radiation;
- Microwave Emission;
- T Tauri Stars;
- Ultraviolet Radiation;
- H Alpha Line;
- Radio Sources (Astronomy);
- Shock Wave Propagation;
- Stellar Radiation;
- X Ray Sources;
- Astrophysics;
- Circumstellar Matter:Ionization;
- Circumstellar Matter:T Tauri Stars