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Related papers: High Altitude Molecular Clouds

200 papers

Filamentary flows toward the centre of molecular clouds have been recognized as a crucial process in the formation and evolution of stellar clusters. In this paper, we present a comprehensive observational study that investigates the gas…

Astrophysics of Galaxies · Physics 2024-01-12 Vineet Rawat , M. R. Samal , D. L. Walker , D. K. Ojha , A. Tej , A. Zavagno , C. P. Zhang , Davide Elia , S. Dutta , J. Jose , C. Eswaraiah , E. Sharma

We present the first detection of complex aldehydes and isomers in three typical molecular clouds located within 200pc of the center of our Galaxy. We find very large abundances of these complex organic molecules (COMs) in the central…

Astrophysics · Physics 2009-11-13 M. A. Requena-Torres , J. Martin-Pintado , S. Martin , M. R. Morris

Using an absorption line from the metastable (J, K) = (3, 3) level of H3+ together with other lines of H3+ and CO observed along several sightlines, we have discovered a vast amount of high temperature (T ~ 250 K) and low density (n ~ 100…

Astrophysics · Physics 2016-08-30 Takeshi Oka , T. R. Geballe , Miwa Goto , Tomonori Usuda , B. J. McCall

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…

The origin of our Galaxy's high-velocity clouds (HVCs) remains a mystery after many decades of effort. In this paper, we use the TNG50 simulation of the IllustrisTNG project to identify cool, dense clouds that match observations of Galactic…

Astrophysics of Galaxies · Physics 2024-10-21 Scott Lucchini , Jiwon Jesse Han , Lars Hernquist , Charlie Conroy

We have mapped the J=1-0 line of SiO in a 1 degree x 12 arcmin. (lxb) region around the Galactic center (GC) with an angular resolution of 2 arcmin. (approx. 4 pc). In contrast to the spatial distribution of other high dipole moment…

Astrophysics · Physics 2009-10-30 J. Martin-Pintado , P. de Vicente , A. Fuente , P. Planesas

We present search results of 22 high latitude (b > 25 deg.) sightlines for OH 18-cm emission using the 305-m radio telescope at the Arecibo Observatory. These sightlines appear in neutral hydrogen emission at intermediate velocities (V_lsr…

Astrophysics of Galaxies · Physics 2023-05-10 Allison Smith , D. Anish Roshi

We present an analysis of the systematic CO(2-1) survey at 12" resolution covering most of the local group spiral M 33 which, at a distance of 840 kpc, is close enough that individual giant molecular clouds (GMCs) can be identified. The…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 P. Gratier , J. Braine , N. J. Rodriguez-Fernandez , K. F. Schuster , C. Kramer , E. Corbelli , F. Combes , N. Brouillet , P. P. van der Werf , M. Röllig

High Velocity Clouds (HVCs) have recently attracted renewed attention as being long lived, massive dark matter dominated clouds of primordial composition distributed throughout the Local Group. In this picture the HVCs would contain a few…

Astrophysics · Physics 2007-05-23 Martin A. Zwaan

We present semi-analytic dynamical models for giant molecular clouds evolving under the influence of HII regions launched by newborn star clusters. In contrast to previous work, we neither assume that clouds are in virial or energetic…

Astrophysics · Physics 2008-11-26 Mark R. Krumholz , Christopher D. Matzner , Christopher F. McKee

The results of a survey of 63 galactic star-forming regions in the 6_K-5_K and 5_K-4_K methyl acetylene lines at 102 and 85 GHz, respectively, are presented. Fourty-three sources were detected at 102 GHz, and twenty-five at 85 GHz. Emission…

Astrophysics · Physics 2009-11-07 A. V. Alakoz , S. V. Kalenskii , V. G. Promislov , L. E. B. Johansson , A. Winnberg

We present CO (1-0) and (2-1) observations of the dwarf starburst galaxy NGC 1569 with the IRAM interferometer on Plateau de Bure. We find the CO emission is not spatially associated with the two super star clusters in the galaxy, but…

Astrophysics · Physics 2007-05-23 C. L. Taylor , S. Huettemeister , U. Klein , A. Greve

New large-scale CO surveys of the first and second Galactic quadrants and the nearby molecular cloud complexes in Orion and Taurus, obtained with the CfA 1.2 m telescope, have been combined with 31 other surveys obtained over the past two…

Astrophysics · Physics 2009-10-31 T. M. Dame , Dap Hartmann , P. Thaddeus

We resolve 182 individual giant molecular clouds (GMCs) larger than 2.5 $\times$ 10$^{5}$ \Msun in the inner disks of five large nearby spiral galaxies (NGC 2403, NGC 3031, NGC 4736, NGC 4826, and NGC 6946) to create the largest such sample…

We investigate the evolution of molecular clouds through the kinematics of their atomic hydrogen (HI) envelopes, using $^{12}\mathrm{CO}$ and 21-cm emission to trace the molecular and atomic gas, respectively. We measure the large-scale…

Astrophysics of Galaxies · Physics 2026-02-03 Thummim Mekuria , Nia Imara

Edge Cloud 2 (EC2) is a molecular cloud, about 35 pc in size, with one of the largest galactocentric distances known to exist in the Milky Way. We present observations of a peak CO emission region in the cloud and use these to determine its…

Astrophysics · Physics 2009-11-13 P. M. E. Ruffle , T. J. Millar , H. Roberts , D. A. Lubowich , C. Henkel , J. M. Pasachoff , G. Brammer , .

We present the germ of a new model for High Velocity Clouds, derived from the idea that the dark matter halo of our Galaxy is in the form of cold, planetary-mass gas clouds. In this picture HVCs arise as a result of disruptive collisions…

Astrophysics · Physics 2007-05-23 Mark Walker , Mark Wardle

We present the statistical properties of molecular clumps in the Galactic center 50 km s$^{-1}$ molecular cloud (GCM-0.02-0.07) based on observations of the CS $J=1-0$ emission line with the Nobeyama Millimeter Array. In the cloud, 37…

Astrophysics of Galaxies · Physics 2015-06-04 Masato Tsuboi , Atsushi Miyazaki

We present here the first results from a high-resolution survey of the 12CO(J=1-0) emission across the northern part of the poorly-enriched Small Magellanic Cloud, made with the ATNF Mopra telescope. Three molecular complexes detected in…

Astrophysics of Galaxies · Physics 2015-05-18 E. Muller , J. Ott , A. Hughes , J. Pineda , T. Wong , N. Mizuno , A. Kawamura , Y. Mizuno , Y. Fukui , T. Onishi , M. Rubio

We use spectroscopic data from HST and FUSE to study the wide range of ionization states of the "highly ionized high-velocity clouds". Studied extensively in OVI absorption, these clouds are usually assumed to be infalling gas in the…

Astrophysics · Physics 2009-11-10 J. A. Collins , J. M. Shull , M. L. Giroux