Carbon monoxide and hydrogen cyanide millimeter-wave emission from stars.

Abstract

Thirty-four stars were surveyed for 2.6-mm CO emission and 49 for 3.4-mm HCN emission. The CO and HCN emission lines were detected in the directions of the carbon stars IRC +10216, IRC +30219, and possibly IRC +00382. The diameter of the CO source in the direction of IRC + 10216 was measured to be 2.3, which is larger than expected for this stellar source. The HCN emission source near IRC +10216 was less than 40" in diameter. Extended CO emission sources were also found in the directions of the stars R Mon and T Tau. The infrared source IRC +40091 (LkHa-101) near the H ii region S222 was also found to have CO emission. Subject headings: carbon stars - circumstellar shells - infrared sources - molecules, interstellar