Evidence for a Thermally Unstable Shock Wave in the VELA Supernova Remnant
Abstract
The emission and absorption line signatures of supernova remnant shock waves provide complementary diagnostic capabilities. This paper presents IUE spectra of the nebulosity and new spectra of HD 72088. Models of the emission and absorption lines from shocked gas are used to derive a shock velocity and elemental depletions. There is evidence from the absorption-line strengths and widths for thermally unstable cooling behind a 150 km/s shock. The shock velocity and swept-up column density estimates of Wallerstein and Balick (1990) are confirmed, and evidence is found for a nonthermal contribution to the pressure.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- December 1991
- DOI:
- 10.1086/170778
- Bibcode:
- 1991ApJ...383..226R
- Keywords:
-
- Nebulae;
- Shock Wave Propagation;
- Stellar Spectra;
- Supernova Remnants;
- Thermal Stability;
- Ultraviolet Spectra;
- Absorption Spectra;
- Emission Spectra;
- Iue;
- Ultraviolet Radiation;
- Astrophysics;
- NEBULAE: INDIVIDUAL NAME: VELA SUPERNOVA REMNANT;
- NEBULAE: SUPERNOVA REMNANTS;
- SHOCK WAVES;
- STARS: INDIVIDUAL HENRY DRAPER NUMBER: HD 72088