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Related papers: Water Abundance in Molecular Cloud Cores

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(Abridged) We present a survey of the water emission in a sample of more than 20 outflows from low mass young stellar objects with the goal of characterizing the physical and chemical conditions of the emitting gas. We have used the HIFI…

We report an upper limit of 9 x 10^{12} cm-2 on the column density of water in the translucent cloud along the line of sight toward HD 154368. This result is based upon a search for the C-X band of water near 1240 \AA carried out using the…

Astrophysics · Physics 2009-10-30 Marco Spaans , David Neufeld , Stephen Lepp , Gary J. Melnick , John Stauffer

We performed Herschel HIFI, PACS and SPIRE observations towards the molecular cloud interacting supernova remnant G349.7+0.2. An extremely broad emission line was detected at 557 GHz from the ground state transition 1_{10}-1_{01} of…

Astrophysics of Galaxies · Physics 2015-10-14 J. Rho , J. W. Hewitt , A. Boogert , M. Kaufman , A. Gusdorf

We present Herschel/HIFI observations of nine transitions of \hho and \hheo towards six high-mass star-forming regions, obtained as part of the PRISMAS Key Program. Water vapor in translucent clouds is detected in absorption along every…

Evaporation of water ice above 100 K in the inner few 100 AU of low-mass embedded protostars (the so-called hot core) should produce quiescent water vapor abundances of ~10^-4 relative to H2. Observational evidence so far points at…

Solar and Stellar Astrophysics · Physics 2015-06-15 Ruud Visser , Jes K. Jorgensen , Lars E. Kristensen , Ewine F. van Dishoeck , Edwin A. Bergin

Observations of the 1(10)-1(01) 556.936 GHz transition of ortho-water with the Submillimeter Wave Astronomy Satellite (SWAS) have revealed the presence of widespread emission and absorption by water vapor around the strong submillimeter…

Astrophysics · Physics 2009-11-07 David A. Neufeld , Edwin A. Bergin , Gary J. Melnick , Paul F. Goldsmith

The formation of massive stars is still not well understood. Accumulating a large amount of mass infalling within a single entity in spite of radiation pressure is possible if, among several other conditions, enough thermal energy is…

Astrophysics of Galaxies · Physics 2017-10-11 F. Herpin , A. Baudry , A. M. S. Richards , M. D. Gray , N. Schneider , K. M. Menten , F. Wyrowski , S. Bontemps , R. Simon , H. Wiesemeyer

We report the first detection of thermal water vapor emission in the 557 GHz, $1_{10} - 1_{01}$ ground state transition of ortho-H$_2$O toward VY Canis Majoris. In observations obtained with the Submillimeter Wave Astronomy Satellite…

Astrophysics · Physics 2009-11-07 Martin Harwit , Edwin A. Bergin

Aims: We study the spatial distribution and kinematics of water emission in a ~64 pc$^2$ region of the Galactic Center (GC) around Sgr A*. We also analyze the water excitation to derive the physical conditions and water abundances in the…

Single-dish spectra and interferometric maps of (sub)mm lines of H2O-18 and HDO are used to study the chemistry of water in eight regions of high-mass star formation. The spectra indicate HDO excitation temperatures of ~110 K and column…

Astrophysics · Physics 2009-11-11 Floris van der Tak , Malcolm Walmsley , Fabrice Herpin , Cecilia Ceccarelli

We have modeled the emission of H2O rotational lines from the extreme C-rich star IRC+10216. Our treatment of the excitation of H2O emissions takes into account the excitation of H2O both through collisions, and through the pumping of the…

Astrophysics · Physics 2009-11-13 Eduardo González-Alfonso , David A. Neufeld , Gary J. Melnick

The HDO/H2O abundance ratio is thought to be a key diagnostic on the evolution of water during the star- and planet-formation process and thus on its origin on Earth. We here present millimeter-wavelength high angular resolution…

Solar and Stellar Astrophysics · Physics 2015-05-20 Jes K. Jorgensen , Ewine F. van Dishoeck

We have mapped six molecular cloud cores in the Orion A giant molecular cloud (GMC), whose kinetic temperatures range from 10 to 30 K, in CCS and N2H+ with Nobeyama 45 m radio telescope to study their chemical characteristics. We identified…

Water is a key molecule in the star formation process, but its spatial distribution in star-forming regions is not well known. We study the distribution of dust continuum and H2O and 13CO line emission in DR21, a luminous star-forming…

Astrophysics of Galaxies · Physics 2019-08-14 F. F. S. van der Tak , M. G. Marseille , F. Herpin , F. Wyrowski

We report the detection of the 1_{10}-1_{11} ground state transition of ortho-H_2D^+ at 372.421 GHz in emission from the young stellar object NGC 1333 IRAS 4A. Detailed excitation models with a power-law temperature and density structure…

Astrophysics · Physics 2009-10-31 Ronald Stark , Floris F. S. van der Tak , Ewine F. van Dishoeck

We have investigated the water abundance in shock-heated molecular gas, making use of $Herschel$ measurements of far-infrared CO and H$_2$O line emissions in combination with $Spitzer$ measurements of mid-IR H$_2$ rotational emissions. We…

We report the results of spectroscopic mapping observations carried out toward a ~1 min x 1 min region within the northern lobe of the outflow from NGC 2071 using the Infrared Spectrograph (IRS) of the Spitzer Space Telescope. These…

Submillimeter rotational lines of H2O are a powerful probe in warm gas regions of the ISM, tracing scales and structures ranging from kpc disks to the most compact and dust-obscured regions of galactic nuclei. The ortho-H2O(423-330) line at…

Astrophysics of Galaxies · Physics 2020-02-05 C. Yang , E. González-Alfonso , A. Omont , M. Pereira-Santaella , J. Fischer , A. Beelen , R. Gavazzi