Results 11 to 20 of about 42,847 (320)
OH+ in Diffuse Molecular Clouds [PDF]
The Astrophysical Journal, 2013 Near ultraviolet observations of OH+ and OH in diffuse molecular clouds reveal a preference for different environments. The dominant absorption feature in OH+ arises from a main component seen in CH+ (that with the highest CH+/CH column density ratio ...
Federman, S. R. +3 more
core +7 more sources
The CH+ Abundance in Turbulent, Diffuse Molecular Clouds [PDF]
Monthly Notices of the Royal Astronomical Society, 2015 The intermittent dissipation of interstellar turbulence is an important energy source in the diffuse ISM. Though on average smaller than the heating rates due to cosmic rays and the photoelectric effect on dust grains, the turbulent cascade can channel ...
Li, Pak Shing +2 more
core +4 more sources
Model calculations for diffuse molecular clouds [PDF]
The Astrophysical Journal, 1974 A steady state isobaric cloud model is developed. The pressure, thermal, electrical, and chemical balance equations are solved simultaneously with a simple one dimensional approximation to the equation of radiative transfer appropriate to diffuse clouds.
A. E. Glassgold, W. D. Langer
openalex +2 more sources
Diffuse molecular clouds at high galactic latitude [PDF]
Symposium - International Astronomical Union, 1991 The IRAS 60 and 100 μm flux from cirrus clouds are commonly explained by dust continuum emission. But this explanation in some cases requires unexpectedly high dust temperatures.We argue that the contribution of fine structure emission of neutral oxygen, O°(63 μm), can be significant in the IRAS 60 μm band. The 0°(63 μm) line emission together with the
R. Stark
openalex +2 more sources
Comprehensive models of diffuse interstellar clouds - Physical conditions and molecular abundances
The Astrophysical Journal Supplement Series, 1986 The limitations of steady state models of interstellar clouds are explored by means of comparison with observational data corresponding to clouds in front of Zeta Per, Zeta Oph, Chi Oph, and Omicron Per. The improved cloud models were constructed to reproduce the observed H and H2(J) column densities for several lines of sight. The main difference from
E. F. van Dishoeck, J. H. Black
exaly +6 more sources
Molecular Formation in Hot Diffuse Clouds [PDF]
Symposium - International Astronomical Union, 1980 A description is given of the processes of molecular formation and destruction in diffuse interstellar clouds and detailed models of the clouds lying towards ζ Ophiuchi, ζ Persei and o Persei are used to assess the validity of gas phase chemistry. Modifications that may arise from shock-heated regions are discussed.
A. Dalgarno
openalex +2 more sources
From Diffuse Gas to Dense Molecular Cloud Cores [PDF]
Space Science Reviews, 2020 Molecular clouds are a fundamental ingredient of galaxies: they are the channels that transform the diffuse gas into stars. The detailed process of how they do it is not completely understood. We review the current knowledge of molecular clouds and their substructure from scales $\sim~$1~kpc down to the filament and core scale.
Javier Ballesteros-Paredes +8 more
openalex +4 more sources
DIFFUSE MOLECULAR CLOUD DENSITIES FROM UV MEASUREMENTS OF CO ABSORPTION [PDF]
The Astrophysical Journal, 2013 We use UV measurements of interstellar CO towards nearby stars to calculate the density in the diffuse molecular clouds containing the molecules responsible for the observed absorption. Chemical models and recent calculations of the excitation rate coefficients indicate that the regions in which CO is found have hydrogen predominantly in molecular form.
P. F. Goldsmith
openalex +5 more sources
Diffuse molecular clouds and the molecular interstellar medium from (13)CO observations of M33 [PDF]
The Astrophysical Journal, 1994 16 pages + 9 figures, uuencoded compressed postscript ...
C. D. Wilson, Constance E. Walker
openalex +3 more sources
Estimating molecular hydrogen in diffuse interstellar clouds [PDF]
Monthly Notices of the Royal Astronomical Society, 1989 La densite de colonne de l'hydrogene moleculaire dans les nuages interstellaires diffus peut etre estimee de maniere satisfaisante par 2 methodes: a partir de la densite de colonne de l'hydrogene atomique combinee avec E(B-V); et a partir des observations optiques des molecules ...
W. B. Somerville, Colin Adrian Smith
openalex +2 more sources