Collisional pumping of OH masers in the 2Pi(1/2) ladder

Journal Article · Thu Feb 01 04:00:00 EST 1990 · Astrophysical Journal; (USA)

DOI:https://doi.org/10.1086/168374· OSTI ID:6851532

Kylafis, N D; Norman, C A ^[1]

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1. Crete Univ., Heraklion (Greece) Space Telescope Science Institute, Baltimore, MD (USA)

The collisional pumping of OH masers in star-forming regions has been studied, and the first detailed calculations of such pumping since collision rates with the correct parities have become available are reported. It is found that collisions of OH with H2 pump not only the J = 1/2 Lambda-doublet but also the J = 3/2 and J = 5/2 Lambda-doublets of 2Pi(1/2). Using parameters inferred by VLBI for W3(OH), it is found that collisional pumping can easily explain the observed brightness temperatures and luminosities of the J = 1/2 Lambda-doublet masers. Furthermore, what the brightness temperature and luminosity should be for the J = 3/2 and J = 5/2 Lambda-doublets in the same region is predicted. 28 refs.

• OSTI ID: 6851532
• Journal Information: Astrophysical Journal; (USA), Journal Name: Astrophysical Journal; (USA) Vol. 350; 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
BRIGHTNESS
COLLISIONS
ELECTRONIC EQUIPMENT
ELEMENTS
EMISSION SPECTRA
EQUIPMENT
HYDROGEN
HYDROXYL RADICALS
INTERSTELLAR SPACE
LUMINOSITY
MASERS
MATHEMATICAL MODELS
MICROWAVE AMPLIFIERS
MICROWAVE EQUIPMENT
NONMETALS
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
PUMPING
RADICALS
SPACE
SPECTRA