Accession Number:

ADA002231

Title:

Radiative Trapping and Hyperfine Structure: HCN (11),

Descriptive Note:

Corporate Author:

OWENS VALLEY RADIO OBSERVATORY PASADENA CALIF

Personal Author(s):

• Kwan,John
• Scoville,N. Z.

Report Date:

1974-01-01

Pagination or Media Count:

16.0

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 10000cc and optical depths in the J 1 to 0 lines greater than 100.

Descriptors:

• *CYANIDES
• *INTERSTELLAR MATTER
• HYPERFINE STRUCTURE
• INTERSTELLAR SPACE

Subject Categories:

• Astrophysics
• Atomic and Molecular Physics and Spectroscopy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE