Existence of molecular hydrogen along lines of sight with low reddening

Journal Article · Mon Mar 15 04:00:00 EST 1976 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/154222· OSTI ID:7341139

York, D G

The existence of molecular hydrogen along lines of sight with low reddening (E(B-V) less than or equal to 0.03) is discussed for the stars HD 28497, ..mu.. Col, ..cap alpha.. Vir, ..beta.. Cen, and lambda Sco. The main observations are of the R(1) features, which for effective rotational temperatures T greater than 200/sup 0/K, are the dominant source of H/sub 2/ transitions. If the formation process for molecular hydrogen is similar to that for regions of greater reddening, the observations indicate that the neutral gas outside standard clouds may be partially in small clouds, though a more diffuse component seems to exist in some cases. Extremely high rotational temperatures are inferred for the H/sub 2/ toward HD 28497. The possibility of formation of H/sub 2/ through the reaction H/sup -/ + H ..-->.. H/sub 2/ + e/sup -/ is briefly discussed. In any case, only small regions seem to contribute to the observed H/sub 2/ column density.

• Research Organization: Princeton Univ. Observatory, NJ
• OSTI ID: 7341139
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 204:3; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ATOM COLLISIONS
CATIONS
CHARGED PARTICLES
CHEMICAL COMPOSITION
CHEMISTRY
COLLISIONS
COSMIC GASES
COSMOCHEMISTRY
CRYOGENIC FLUIDS
ELEMENTS
FLUIDS
GASES
HYDROGEN
HYDROGEN IONS
HYDROGEN IONS 1 PLUS
INTERSTELLAR SPACE
ION COLLISIONS
ION-ATOM COLLISIONS
IONS
MOLECULES
NONMETALS
RED SHIFT
SPACE
SPECTRA
STARS