Measurements of the H$sub 2$CO 6-centimeter excitation temperature. I. Dark dust clouds

Journal Article · Sun Jul 15 00:00:00 EDT 1973 · Astrophys. J., v. 183, no. 2, pp. 441-448

OSTI ID:4342989

Heiles, C

Highly accurate H/sub 2/CO 6-cm line profiles were observed in 14 positions located in dark dust clouds. Analyses of the relative strengths of the hyperfine components showed no anomalies. Therefore, excitation temperatures were derived for 10 positions which exhibited measurable saturation due to optical-depth effects. Nine of these positions have nearly the same excitation temperature, about 1.6M. The other position definitely has a higher excitation temperature, about 2.2 deg K; this position is located in a cloud whose kinetic temperature is 18 deg K, substantially hotter and also probably denser than the usual'' dark dust cloud. (auth)

• Research Organization: Department of Astronomy, University of California, Berkeley
• NSA Number: NSA-29-022053
• OSTI ID: 4342989
• Journal Information: Astrophys. J., v. 183, no. 2, pp. 441-448, Other Information: Orig. Receipt Date: 30-JUN-74
• Country of Publication: United States
• Language: English

Related Subjects

N56500* -Physics (Astrophysics & Cosmology)-Galaxies
*FORMALDEHYDE- NEBULAE
*NEBULAE- EXCITATION
COSMIC DUST
COSMIC RADIO SOURCES
DOPPLER BROADENING
HYPERFINE STRUCTURE
INTERSTELLAR SPACE