Results 1 to 10 of about 2,285 (166)
Kinetic Jeans instability in FOG framework [PDF]
Scientific ReportsThe key mechanism triggering the complex dynamics of astrophysical structure formation in extensive evolutionary clouds is indeed sourced in the non-local gravitational (Jeans) instability. Motivated by recent astrophysical observations, establishing the
Mritunjoy Das +2 more
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Two populations of diffuse molecular clouds
Astrophysical Journal, 1988 Sensitive CO and (C-13)O measurements have been made toward a number of diffuse clouds and high-latitude molecular clouds (HLCs). The results suggest that the diffuse clouds are an inhomogeneous class of objects which can be separated according to their CO column density.
Leo Blitz, Elizabeth A Lada
exaly +2 more sources
The contribution of unresolved sources on the gamma-ray spectrum of molecular clouds [PDF]
EPJ Web of Conferences, 2023 Fermi-LAT observations of the large-scale diffuse gamma-ray emission unveiled that in some locations, towards the inner Galaxy, the spectrum of this component is harder than the local one, measured at the Earth position. If this signal is associated with
Vecchiotti Vittoria +3 more
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Formation of Dust Filaments in the Diffuse Envelopes of Molecular Clouds [PDF]
The Astrophysical Journal, 2021 Abstract The path to understanding star formation processes begins with the study of the formation of molecular clouds. The outskirts of these clouds are characterized by low column densities that allow the penetration of ultraviolet radiation, resulting in a nonnegligible ionization fraction and the charging of the small dust grains ...
Leire Beitia-Antero +2 more
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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), while OH follows CN absorption.
Porras, A. J. +3 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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The Astrophysical Journal Letters, 2023 Observations of OH ^+ are used to infer the interstellar cosmic ray ionization rate in diffuse atomic clouds, thereby constraining the propagation of cosmic rays through and the shielding by interstellar clouds, as well as the low energy cosmic ray ...
Ábel Kálosi +14 more
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Shaken or Stirred: The Diffuse Interstellar Medium with Exceptionally High SiO Abundance
The Astrophysical Journal, 2023 Interstellar shocks, a key element of stellar feedback processes, shape the structure of the interstellar medium (ISM) and are essential for the chemistry, thermodynamics, and kinematics of interstellar gas.
Daniel R. Rybarczyk +2 more
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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
openaire +2 more sources
The Astrophysical Journal, 2023 We present the results of ALMA-ACA 7 m array observations in ^12 CO( J = 2–1), ^13 CO( J = 2–1), and C ^18 O( J = 2–1) line emission toward the molecular-gas disk in the Local Group spiral galaxy M33 at an angular resolution of 7.″31 × 6.″50 (30 × 26 pc).
Kazuyuki Muraoka +21 more
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