Results 11 to 20 of about 42,575 (298)
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
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CN excitation and electron densities in diffuse molecular clouds [PDF]
Monthly Notices of the Royal Astronomical Society, 2013 Utilising previous work by the authors on the spin-coupled rotational cross-sections for electron-CN collisions, data for the associated rate coefficients is presented.
Faure, Alexandre +2 more
core +9 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.
Ballesteros-Paredes, Javier +9 more
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TRACING TURBULENT AMBIPOLAR DIFFUSION IN MOLECULAR CLOUDS [PDF]
The Astrophysical Journal, 2010 Though flux freezing is a good approximation frequently assumed for molecular clouds, ambipolar diffusion (AD) is inevitable at certain scales. The scale at which AD sets in can be a crucial parameter for turbulence and the star formation process.
Li, Hua-bai +3 more
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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
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Molecular cloud abundances and anomalous diffusion [PDF]
Astronomische Nachrichten, 2007 AbstractThe chemistry of molecular clouds has been studied for decades, with an increasingly general and sophisticated treatment of the reactions involved. Yet the treatment of turbulent diffusion has remained extremely sketchy, assuming simple Fickian diffusion with a scalar diffusivity D.
Marschalko, G. +2 more
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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, C. A. Smith
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Galaxy chemical evolution models: The role of molecular gas formation [PDF]
, 2017 In our classical grid of multiphase chemical evolution models, star formation in the disc occurs in two steps: first, molecular gas forms, and then stars are created by cloud-cloud collisions or interactions of massive stars with the surrounding ...
Ascasibar, Yago +4 more
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Far-ultraviolet Dust Extinction and Molecular Hydrogen in the Diffuse Milky Way Interstellar Medium
The Astrophysical Journal, 2023 We aim to compare variations in the full-UV dust extinction curve (912–3000 Å), with the H i /H _2 /total H content along diffuse Milky Way sightlines, to investigate possible connections between ISM conditions and dust properties. We combine an existing
Dries Van De Putte +4 more
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Frontiers in Astronomy and Space Sciences, 2021 Stellar systems are often formed through the collapse of dense molecular clouds which, in turn, return copious amounts of atomic and molecular material to the interstellar medium.
Duncan V. Mifsud +6 more
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