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Related papers: Modelling [CI] emission from turbulent molecular c…

200 papers

To complement the optical absorption-line survey of diffuse molecular gas in Paper I, we obtained and analyzed far ultraviolet H$_2$ and CO data on lines of sight toward stars in Cep OB2 and Cep OB3. Possible correlations between column…

Astrophysics · Physics 2009-11-13 K. Pan , S. R. Federman , Y. Sheffer , B. -G. Andersson

We have constructed three-dimensional models for the equilibrium abundance of molecular hydrogen within diffuse interstellar clouds of arbitrary geometry that are illuminated by ultraviolet radiation. The position-dependent photo-…

Astrophysics · Physics 2009-10-30 Marco Spaans , David A. Neufeld

The outer Galaxy presents an optimal setting for investigating molecular clouds and star formation in environments with low metallicity. A total of 72 Galactic edge clouds were surveyed using the CO\,(2--1) line with the IRAM\,30\,m…

We present results from high-resolution three-dimensional simulations of turbulent interstellar gas that self-consistently follow its coupled thermal, chemical and dynamical evolution, with a particular focus on the formation and…

Solar and Stellar Astrophysics · Physics 2015-05-13 S. C. O. Glover , C. Federrath , M. -M. Mac Low , R. S. Klessen

Molecular clouds (MC) are structures of dense gas in the interstellar medium (ISM), that extend from ten to a few hundred parsecs and form the main gas reservoir available for star formation. Hydrodynamical simulations of varying complexity…

We further characterize the structures tentatively identified on thermal and chemical grounds as the sites of dissipation of turbulence in molecular clouds (Papers I and II). Our study is based on two-point statistics of line centroid…

Astrophysics · Physics 2009-11-13 Pierre Hily-Blant , Edith Falgarone , Jerome Pety

We discuss constraints on the rates of stirring and dissipation of MHD turbulence in molecular clouds. Recent MHD simulations suggest that turbulence in clouds decays rapidly, thus providing a significant source of energy input,…

Astrophysics · Physics 2009-11-06 Shantanu Basu , Chigurupati Murali

(Abridged) We present a series of decaying turbulence simulations that represent a cluster-forming clump within a molecular cloud, investigating the role of magnetic fields on the formation of potential star-forming cores. We present an…

Astrophysics · Physics 2007-11-07 David A. Tilley , Ralph E. Pudritz

The low-mass condensations (LMCs) have been observed within the molecular cloud cores. In this research, we investigate the effect of isobaric thermal instability (TI) applied for forming these LMCs. For this purpose, at first we…

Astrophysics of Galaxies · Physics 2015-05-27 Mohsen Nejad-Asghar

We analyze the conditions for detection of CO(1-0) emission in the Large Magellanic Cloud (LMC), using the recently completed second NANTEN CO survey. In particular, we investigate correlations between CO integrated intensity and HI…

Astrophysics of Galaxies · Physics 2011-02-11 T. Wong , A. Hughes , Y. Fukui , A. Kawamura , N. Mizuno , J. Ott , E. Muller , J. L. Pineda , D. E. Welty , S. Kim , Y. Mizuno , M. Murai , T. Onishi

Context: Atomic and molecular cloud formation is a dynamical process. However, kinematic signatures of these processes are still observationally poorly constrained. Methods: Targeting the cloud-scale environment of the prototypical infrared…

Emission line profiles of tracer molecule H$_2$CO 140 GHz transition from gravitational core collapsing clouds in the dynamic process of forming protostars are calculated, using a simple ray-tracing radiative transfer model. Three…

Solar and Stellar Astrophysics · Physics 2015-05-13 Yang Gao , Yu-Qing Lou , Kinwah Wu

We examine several different simplified approaches for modelling the chemistry of CO in three-dimensional numerical simulations of turbulent molecular clouds. We compare the different models both by looking at the behaviour of integrated…

Astrophysics of Galaxies · Physics 2015-05-27 S. C. O. Glover , P. C. Clark

We have mapped two molecular clouds at (l, b) = (3.2 degrees, + 0.3 degrees) and (l, b) = (5.4 degrees, -0.5 degrees) in 21-cm line and continuum emission. These clouds show unusually large velocity dispersions of more than 100 km/s (FWHM)…

Astrophysics · Physics 2015-06-24 Harald Riffert , Pawan Kumar , W. K. Huchtmeier

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…

Astrophysics of Galaxies · Physics 2015-09-11 Andrew Myers , Christopher McKee , Pak Shing Li

We report the first uniform and systematic study of dust and molecular gas in nearby molecular clouds. We use surveys of dust extinction and emission to determine the opacity and map the distribution of the dust within a dozen local clouds…

Astrophysics of Galaxies · Physics 2022-05-25 John Arban Lewis , Charles J. Lada , Thomas Dame

We report results of a project to map HCN and HCO+ J = 1-0 emission toward a sample of molecular clouds in the inner Galaxy, all containing dense clumps that are actively engaged in star formation. We compare these two molecular line…

Astrophysics of Galaxies · Physics 2020-05-20 Neal J. Evans , Kee-Tae Kim , Jingwen Wu , Zhang Chao , Mark Heyer , Tie Liu , Quang Nguyen-Luong , Jens Kauffmann

We present spectral data cubes of the [CI] 809GHz, 12CO 115GHz, 13CO 110GHz and HI 1.4GHz line emission from an 1 square degree region along the l = 328{\deg} (G328) sightline in the Galactic Plane. Emission arises principally from gas in…

We analyse extinction maps of nearby Giant Molecular Clouds to forge a link between driving processes of turbulence and modes of star formation. Our investigation focuses on cloud structure in the column density range above the self…

Astrophysics of Galaxies · Physics 2015-05-28 J. Rowles , D. Froebrich

We report ALMA observations of the neutral atomic carbon transitions [CI] and multiple CO lines in a sample of $\sim30$ main sequence galaxies at $z\sim1$, including novel information on [CI](2-1) and CO(7-6) for 7 of such normal objects.…