12C/13C Abundance Ratios from Observations of Interstellar H,13C'60
Abstract
A study of the interstellar H212C16O/H213C160 abundance ratio in the direction of seven H ii regions suggests that the galactic 12Ci13C ratio is approximately terrestrial except, possibly, in massive clouds near the galactic center. If a systematic difference does exist between the typical interstellar H212C16O/H213C16O ratio and the terrestrial 12Ci13C ratio, it appears that the latter ratio is the larger. An unsuccessful search for the 1ii-1io transition of H212C17O in Sgr B2 yielded an H212C17OlH213C'60 abundance <1/7. Subject headings: abundances, nebular - molecules, interstellar - nebulae - radio lines
- Publication:
-
The Astrophysical Journal
- Pub Date:
- April 1974
- DOI:
- 10.1086/152791
- Bibcode:
- 1974ApJ...189..217Z