A dense molecular cloud impacted by the W28 supernova remnant
Abstract
Molecular spectra and an infrared survey of a dense molecular cloud obscuring a part of the optical nebulosity associated with the supernova remnant W28 have been obtained. The spectra reveal a warm dense core in a region of substantial line broadening near a maximum of nonthermal radio emission from the remnant. A small (2 km/s) shift in the velocity of peak molecular emission also occurs in this region. No embedded infrared source capable of heating the cloud appears to be present. The cloud appears to have been impacted by the expanding supernova remnant. The cloud appears to be an ambient cloud only recently compressed and heated by the nearby remnant; no evidence for star formation has been found. The remarkably broad HCO(+) lines found near the cloud core originate in a region of enhanced ionization in the cloud, quite possibly resulting from penetration of the cloud by energetic radiation from the remnant.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- April 1981
- DOI:
- 10.1086/158790
- Bibcode:
- 1981ApJ...245..105W
- Keywords:
-
- Infrared Astronomy;
- Interstellar Matter;
- Molecular Clouds;
- Molecular Spectra;
- Supernova Remnants;
- Carbon Monoxide;
- Emission Spectra;
- Gas Density;
- Gas Ionization;
- Nebulae;
- Nonthermal Radiation;
- Radio Emission;
- Spectral Line Width;
- Astronomy