English
Related papers

Related papers: Cloud Structure and Physical Conditions in Star-Fo…

200 papers

We have studied four complex organic molecules (COMs), methyl formate ($CH_3OCHO$), dimethyl ether ($CH_3OCH_3$), formamide ($NH_2CHO$), and ethyl cyanide ($C_2H_5CN$), towards a large sample of 39 high-mass star-forming regions…

Astrophysics of Galaxies · Physics 2020-09-09 A. Coletta , F. Fontani , V. M. Rivilla , C. Mininni , L. Colzi , Á. Sánchez-Monge , M. T. Beltrán

The relationship between young stellar clusters and respective parental molecular clouds is still an open issue: for instance, are the similarities between substructures of clouds and clusters just a coincidence? Or would they be the…

We model the temperature and chemical structure of molecular clouds as a function of depth into the cloud, assuming a cloud of constant density n illuminated by an external FUV (6 eV < E < 13.6 eV) flux G_0 (scaling factor in multiples of…

Astrophysics · Physics 2011-02-11 David Hollenbach , Michael J. Kaufman , Edwin A. Bergin , Gary J. Melnick

Massive star-forming regions exhibit an extremely rich and diverse chemistry, which in principle provides a wealth of molecular probes, as well as laboratories for interstellar prebiotic chemistry. Since the chemical structure of these…

The structure of molecular clouds can be characterized with the probability distribution function (PDF) of the mass surface density. In particular, the properties of the distribution can reveal the nature of the turbulence and star…

Astrophysics of Galaxies · Physics 2015-06-22 Rachel L. Ward , James Wadsley , Alison Sills

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,…

Astrophysics of Galaxies · Physics 2021-02-24 L. Beitia-Antero , A. I. Gómez de Castro , J. C. Vallejo

Molecular line CN, CS and mm continuum observations of two intermediate- to high-mass star-forming regions - IRAS20293+3952 and IRAS19410+2336 - obtained with the Plateau de Bure Interferometer at high spatial resolution reveal interesting…

Astrophysics · Physics 2009-11-10 H. Beuther , P. Schilke , F. Wyrowski

We investigate physical properties of molecular clouds in disc galaxies with different morphology: a galaxy without prominent structure, a spiral barred galaxy and a galaxy with flocculent structure. Our $N$-body/hydrodynamical simulations…

Astrophysics of Galaxies · Physics 2016-03-02 S. A. Khoperskov , E. O. Vasiliev , D. A. Ladeyschikov , A. M. Sobolev , A. V. Khoperskov

The physical conditions in a collapsing cloud can be traced by observations of molecular lines. To correctly interpret these observations the abundance distributions of the observed species need to be derived. The chemistry in a collapsing…

Solar and Stellar Astrophysics · Physics 2009-11-13 R. J. van Weeren , C. Brinch , M. R. Hogerheijde

We have developed an iterative procedure to systematically combine the millimeter and submillimeter images of OB cluster-forming molecular clouds, which were taken by ground based (CSO, JCMT, APEX, IRAM-30m) and space telescopes (Herschel,…

By observing radiation-affected gas in the Cepheus B molecular cloud we probe whether the sequential star formation in this source is triggered by the radiation from newly formed stars. We used the dual band receiver GREAT onboard SOFIA to…

Astrophysics of Galaxies · Physics 2015-06-04 B. Mookerjea , V. Ossenkopf , O. Ricken , R. Guesten , U. U. Graf , K. Jacobs , C. Kramer , R. Simon , J. Stutzki

The molecular gas content of local early-type galaxies is constrained and discussed in relation to their evolution. First, as part of the Atlas3D survey, we present the first complete, large (260 objects), volume-limited single-dish survey…

We present high-resolution, high signal to noise absorption-line observations of CN, Ca II, Ca I, CH^+, and CH along twenty lines of sight toward members of the Pleiades. The acquired data enable the most detailed study to date of the…

Astrophysics · Physics 2010-11-11 A. M. Ritchey , M. Martinez , K. Pan , S. R. Federman , D. L. Lambert

ABRIDGED: Context: HI and CO large scale surveys of the Milky Way trace the diffuse atomic clouds and the dense shielded regions of molecular hydrogen clouds. However, until recently, we have not had spectrally resolved C+ surveys to…

Astrophysics of Galaxies · Physics 2015-06-18 W. D. Langer , T. Velusamy , J. L. Pineda , K. Willacy , P. F. Goldsmith

We have carried out wide-field (0.17 degree^2) and high-angular resolution (21.3 arcsec ~ 0.04 pc) observations in [CI] line toward the Orion-A giant molecular cloud with the Atacama Submillimeter Telescope Experiment (ASTE) 10 m telescope…

Grain-surface chemistry plays a crucial role in the formation of molecules of astrobiological interest, including H$_{2}$S and complex organic molecules (COMs). They are commonly observed in the gas phase toward star-forming regions, but…

Astrophysics of Galaxies · Physics 2025-09-10 D. Navarro-Almaida , A. Taillard , A. Fuente , P. Caselli , R. Martín-Doménech , J. J. Miranzo-Pastor

Constraints on the density and thermal 3D structure of the dense molecular cloud core Rho Oph D are derived from a detailed 3D radiative transfer modeling. Two ISOCAM images at 7 and 15 micron are fitted simultaneously by representing the…

Astrophysics · Physics 2009-11-10 J. Steinacker , A. Bacmann , Th. Henning , R. Klessen , M. Stickel

We study infrared emission of 17 isolated, diffuse clouds with masses of order solar masses, to test the hypothesis that grain property variations cause the apparently low gas-to-dust ratios that have been measured in those clouds. Maps of…

Astrophysics of Galaxies · Physics 2018-08-13 William T. Reach , Jean-Philippe Bernard , Thomas Jarrett , Carl Heiles

We observed the 9-cm Lambda-doubling lines of CH along the dense filament of TMC-1. The CH column densities were compared with the total H2 column densities derived using the 2MASS NIR data and previously published SCUBA maps and with OH…