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Related papers: The physical state of selected cold clumps

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We are addressing the sites of isolated low mass star formation in the solar neighbourhood, i.e. small cloud cores within one kiloparsec. We aim at determining the physical parameters of the cores, i.e., temperature, volume density, column…

Astrophysics of Galaxies · Physics 2017-03-21 Bengt Larsson , René Liseau

We present an overview of a high-mass star formation region through the major (sub-)mm, and far-infrared cooling lines to gain insight into the physical conditions and the energy budget of the molecular cloud. We used the KOSMA 3m telescope…

Astrophysics · Physics 2009-11-11 H. Jakob , C. Kramer , R. Simon , N. Schneider , V. Ossenkopf , S. Bontemps , U. U. Graf , J. Stutzki

We present the first search for spinning dust emission from a sample of 34 Galactic cold cores, performed using the CARMA interferometer. For each of our cores we use photometric data from the Herschel Space Observatory to constrain N_{H},…

We study the origin of the cold molecular clumps in quasar outflows, recently detected in CO and HCN emission. We first describe the physical properties of such radiation-driven outflows and show that a transition from a momentum- to an…

Astrophysics of Galaxies · Physics 2016-12-14 Andrea Ferrara , Evan Scannapieco

Sun-like stars form from the contraction of cold and dense interstellar clouds. How the collapse proceeds and what are the main physical processes driving it, however, is still under debate and a final consensus on the timescale of the…

The determination of the fractional electron abundance, Xe, in protostellar cores relies on observations of molecules, such as DCO+, H13CO+ and CO, and on chemical models to interpret their abundance. Studies of protostellar cores have…

Astrophysics · Physics 2009-11-10 Paolo Padoan , Karen Willacy , William Langer , Mika Juvela

Using the APEX-12m telescope, continuum maps at 350~$\mu$m of eight gas-dust clouds from the southern hemisphere are obtained. Clouds are associated with the regions of massive star and star cluster formation and have dense cores. Core…

Astrophysics of Galaxies · Physics 2023-01-12 L. E. Pirogov

We estimate the dust temperatures of the clumps in the rho Oph main cloud taking into account the 3D geometry of the region, and external heating from the interstellar radiation field and from HD147879,a nearby luminous B2V star, which is…

Astrophysics · Physics 2009-06-23 D. Stamatellos , A. P. Whitworth , D. Ward-Thompson

We observe 84 candidate young high-mass sources in the rare isotopologues C17O and C18O to investigate whether there is evidence for depletion (freeze-out) towards these objects. Observations of the J=2-1 transitions of C18O and C17O are…

Astrophysics · Physics 2009-11-13 H. S. Thomas , G. A. Fuller

We present the first results of a multi-wavelength survey, incoporating Herschel-SPIRE, Spitzer, GALEX and ATCA observations, of a 1 deg x 1 deg field centred on Centaurus A. As well as detecting the inner lobes of the active galactic…

Context: Molecular clouds are the prime locations of star formation. These clouds contain filamentary structures and cores which are crucial in the formation of young stars. Aims: In this work, we aim to quantify the physical properties of…

Astrophysics of Galaxies · Physics 2024-03-19 Divyansh Dewan , Archana Soam , Guo-Yin Zhang , Akhil Lasrado , Saikhom Pravash Singh , Chang Won Lee

Using the ISOPHOT Serendipity Survey (ISOSS) at 170um a sample of galactic star-forming regions exhibiting very cold dust temperatures (< 20 K) and high masses (> 100 M_sun) has been established. We characterise the star-forming content of…

Astrophysics · Physics 2010-05-19 M. Hennemann , S. M. Birkmann , O. Krause , D. Lemke

(Abridged) Context. With the Herschel Space Observatory, lines of simple molecules (C+, O, and CO) have been observed in the atmosphere of protoplanetary disks. When combined with ground-based [CI], all principle forms of carbon can be…

Solar and Stellar Astrophysics · Physics 2015-06-03 Simon Bruderer , Ewine F. van Dishoeck , Steven D. Doty , Gregory J. Herczeg

We present a catalogue of dense cores in a $\sim 4^\circ\times2^\circ$ field of the Taurus star-forming region, inclusive of the L1495 cloud, derived from Herschel SPIRE and PACS observations in the 70 $\mu$m, 160 $\mu$m, 250 $\mu$m, 350…

We have measured the deuterium fractionation (through the column density ratio N(N2D+)/N(N2H+)) and the CO depletion factor (ratio between expected and observed CO abundance) in a sample of 10 high-mass protostellar candidates, in order to…

Astrophysics · Physics 2009-11-11 F. Fontani , P. Caselli , A. Crapsi , R. Cesaroni , S. Molinari , L. Testi , J. Brand

Aims. Young stars interact vigorously with their surroundings, as evident from the highly rotationally excited CO (up to Eup=4000 K) and H2O emission (up to 600 K) detected by the Herschel Space Observatory in embedded low-mass protostars.…

Solar and Stellar Astrophysics · Physics 2015-05-30 R. Visser , L. E. Kristensen , S. Bruderer , E. F. van Dishoeck , G. J. Herczeg , C. Brinch , S. D. Doty , D. Harsono , M. G. Wolfire

We obtained the first view in H$^{13}$CO$^+$ $J=1-0$ and a high resolution map in thermal SiO lines of G0.11$-$0.11, which is a molecular cloud situated between the Galactic Center radio arc and Sgr A. From a comparison with previous line…

Astrophysics · Physics 2009-11-13 T. Handa , M. Sakano , S. Naito , M. Hiramatsu , M. Tsuboi

We aim to reveal the physical properties and chemical composition of the cores in the California molecular cloud (CMC), so as to better understand the initial conditions of star formation. We made a high-resolution column density map…

We report the first ensemble results from the FUSE survey of molecular hydrogen in lines of sight with A_V $\gtrsim$ 1 mag. We have developed techniques for fitting computed profiles to the low-J lines of H2, and thus determining column…

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