Spectra of circularly polarized radiation from astrophysical OH masers

Journal Article · Mon Oct 01 04:00:00 EDT 1990 · Astrophysical Journal; (USA)

DOI:https://doi.org/10.1086/169228· OSTI ID:6439636

Nedoluha, G E; Watson, W D ^[1]

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1. Illinois Univ., Urbana (USA)

A striking feature of astrophysical masers is the tendency for either one or the other of the circular polarizations to dominate in the radiation from the strong, widely observed masing transitions of OH at 18 cm. Spectral line profiles are calculated for polarized maser radiation due to the combined effects of a velocity gradient and, as is indicated for these transitions, a Zeeman splitting that is at least comparable with the thermal contributions to the breadths of the spectral lines. The resulting spectral features are similar in appearance, including the presence of large net circular polarization and narrow line breadths, to the commonly observed spectra of OH masers in molecular clouds. The calculations presented here are performed as a function of frequency without making the approximations of a large velocity gradient. Rapid cross relaxation, which has been advocated by others for the OH masers, is assumed. 31 refs.

• OSTI ID: 6439636
• Journal Information: Astrophysical Journal; (USA), Journal Name: Astrophysical Journal; (USA) Vol. 361; ISSN ASJOA; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AMPLIFIERS
ELECTROMAGNETIC RADIATION
ELECTRONIC EQUIPMENT
EQUIPMENT
HYDROXYL RADICALS
INFRARED RADIATION
INTERSTELLAR SPACE
LINE WIDTHS
MAGNETIC FIELDS
MASERS
MICROWAVE AMPLIFIERS
MICROWAVE EQUIPMENT
POLARIZATION
RADIATIONS
RADICALS
SPACE
ZEEMAN EFFECT