Hydroxyl absorption in NGC 6240, NGC 2623, and NGC 2640

Journal Article · Sat Jun 15 04:00:00 EDT 1985 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/163245· OSTI ID:5189261

Baan, W A; Haschick, A D; Buckley, D; Schmelz, J T

Extragalactic absorption of hydroxyl is reported for the galaxies NGC 520, NGC 2623, and NGC 6240. H I absorption has also been detected in these galaxies. The properties of the H I and OH absorption features are compared for these galaxies and for other galaxies with absorption in both OH and H I. The hyperfine ratio for the 1667 and 1665 MHz hydroxyl transitions for most extragalactic absorption lines falls within LTE range. The characteristics of extragalactic OH absorption lines are consistent with the existence of dense molecular disks in the inner parts of the galaxies. An asymmetry in a number of extragalactic OH absorption lines suggests a peculiar velocity structure for the absorbing molecular disk.

• Research Organization: Arecibo Observatory. The Arecibo Observatory is part of the National Astronomy and Ionosphere Center, operated by Cornell University under contract with the National Science Foundation
• OSTI ID: 5189261
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 293:2; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABSORPTION
ABSORPTION SPECTRA
COSMIC RADIO SOURCES
ELEMENTS
GALAXIES
GALAXY NUCLEI
HYDROGEN
HYDROXYL RADICALS
INTERSTELLAR GRAINS
NONMETALS
PARTICLES
RADICALS
SPECTRA