Radiative Trapping and Hyperfine Structure: HCN (11),
Abstract
The anomalous weakness of the F = 1 to 1 hyperfine component in the J = 1 to 0 emission of interstellar HCN can be caused by radiative trapping in the J = 2 to 1 lines. The anomaly is readily produced if the J = 1 levels are populated largely by collisional excitation from J = 0 to J = 2 followed by radiative decay to J = 1 with the J = 2 to 1 lines optically thick. Regions where the anomaly is found probably have H2 density less than 10000/cc and optical depths in the J = 1 to 0 lines greater than 100.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1974
- Accession Number
- ADA002231
Entities
People
- John Kwan
- N. Z. Scoville
Organizations
- Owens Valley Radio Observatory