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Related papers: Water masers in dusty environments

200 papers

We report the results of a blind search for 22-GHz water masers in two regions, covering approximately half a square degree, within the giant molecular cloud associated with RCW 106. The complete search of the two regions was carried out…

We present observations of the 36- (4_-1 -> 3_0E) and 84-GHz (5_-1 -> 4_0 E) class I methanol maser transitions towards a sample of 94 known class I sites. These observations resulted in 93 and 92 detections in the 84- and 36-GHz…

Astrophysics of Galaxies · Physics 2019-01-30 Shari Breen , Yanett Contreras , Joanne Dawson , Simon Ellingsen , Maxim Voronkov , Tiege McCarthy

Class I CH$_3$OH masers trace interstellar shocks. They have received little attention mostly as a consequence of their low luminosities; this situation has changed recently and Class I masers are now routinely used as signposts of…

Astrophysics of Galaxies · Physics 2016-07-13 S. Leurini , K. M. Menten , C. M. Walmsley

We report the discovery of water maser emission in five active galactic nuclei (AGN) with the 100-m Green Bank Telescope (GBT). The positions of the newly discovered masers, measured with the VLA, are consistent with the optical positions…

Astrophysics · Physics 2008-11-26 Paul T. Kondratko , Lincoln J. Greenhill , James M. Moran

Single flux density measurements at observed-frame sub-millimeter and millimeter wavelengths are commonly used to probe dust and gas masses in galaxies. In this Letter, we explore the robustness of this method to infer dust mass, focusing…

Astrophysics of Galaxies · Physics 2022-11-16 R. K. Cochrane , C. C. Hayward , D. Anglés-Alcázar

After melting, at ambient pressure, the density of water continues to increase with temperature until it reaches a maximum around 4 {\deg}C. For nearly a century, this phenomenon has been qualitatively attributed to a mixture of ordered and…

Chemical Physics · Physics 2026-03-31 Yizhi Song , Renxi Liu , Chunyi Zhang , Yifan Li , Biswajit Santra , Mohan Chen , Michael L. Klein , Xifan Wu

We present a survey in the 6_{16}-5_{23} rotational water transition toward 33 galactic ultracompact HII regions. Maser emission is detected toward 18 of these sources; two are new detections. High quality spectra are provided for all 18…

Astrophysics · Physics 2008-11-26 S. Kurtz , P. Hofner

We report observations of a sample of high redshift sources (1.8<z<4.7), mainly radio-quiet quasars, at 350 microns using the SHARC bolometer camera at the Caltech Submillimeter Observatory. Nine sources were detected (>4-sigma) and upper…

We present deep Herschel-PACS spectroscopy of far-infrared water lines from a sample of four protoplanetary disks around solar-mass stars, selected to have strong water emission at mid-infrared wavelengths. By combining the new Herschel…

Water bath calorimetry was used to demonstrate one more peculiar phenomenon associated with a certain class of mixed gas plasmas termed resonant transfer, or RT plasmas. Specifically, He/H2 (10%) (500 mTorr), Ar/H2 (10%) (500 mTorr), and…

Plasma Physics · Physics 2009-11-10 J. Phillips , R. L. Mills , X. Chen

We have mapped 63 regions forming high-mass stars in CS J=5-4 using the CSO. The CS peak position was observed in C34S J=5-4 towards 57 cores and in 13CS J=5-4 towards the 9 brightest cores. The sample is a subset of a sample originally…

Astrophysics · Physics 2009-11-10 Yancy L. Shirley , Neal J Evans , Kaisa E. Young , Claudia Knez , Daniel T. Jaffe

Understanding water deuterium fractionation is important for constraining the mechanisms of water formation in interstellar clouds. Observations of HDO and H$_2^{18}$O transitions were carried out towards the high-mass star-forming region…

In dense parts of interstellar clouds (> 10^5 cm^-3), dust & gas are expected to be in thermal equilibrium, being coupled via collisions. However, previous studies have shown that the temperatures of the dust & gas may remain decoupled even…

Solar and Stellar Astrophysics · Physics 2015-08-05 E. Koumpia , P. M. Harvey , V. Ossenkopf , F. F. S. van der Tak , B. Mookerjea , A. Fuente , C. Kramer

Within low-mass star formation, water vapor plays a key role in the chemistry and energy balance of the circumstellar material. The Herschel Space Observatory will open up the possibility to observe water lines originating from a wide range…

Seven Class 0 sources mapped with SCUBA at 850 and 450 micron are modeled using a one dimensional radiative transfer code. The modeling takes into account heating from an internal protostar, heating from the ISRF, realistic beam effects,…

Astrophysics · Physics 2009-09-28 Yancy L. Shirley , Neal J. Evans , Jonathan M. C. Rawlings

It was recently discovered that the temperature in the surface layer of externally heated optically thick gray dust clouds increases with the optical depth for some distance from the surface, as opposed to the normal decrease in temperature…

Astrophysics · Physics 2008-11-26 Dejan Vinkovic

We present MERLIN observations of OH, water and methanol masers towards the young high mass stellar object IRAS 20126+4104. Emission from the 1665-MHz OH, 22-GHz H_2O and 6.7-GHz CH_3OH masers is detected and all originates very close to…

Astrophysics of Galaxies · Physics 2011-07-05 K. A. Edris , G. A. Fuller , R. J. Cohen , S. Etoka

Recent observations of the ground state transition of HDO at 464 GHz towards the protoplanetary disk of DM Tau have detected the presence of water vapor in the regions just above the outer disk midplane (Ceccarelli et al 2005). In the…

Astrophysics · Physics 2009-11-13 C. Dominik , C. Ceccarelli , D. Hollenbach , M. Kaufman

We investigate the circumstellar dust shell of the water fountain source IRAS 16342-3814. We performed two-dimensional radiative transfer modeling of the dust shell, taking into account previously observed spectral energy distributions…

Solar and Stellar Astrophysics · Physics 2015-06-05 K. Murakawa , H. Izumiura

We have conducted multi-epoch EVN observations of the 22.2 GHz water masers towards four high-mass star forming regions (Sh 2-255 IR, IRAS 23139+5939, WB89-234, and OMC2). The (three) observing epochs span a time range of 6 months. In each…

Astrophysics · Physics 2016-08-30 C. Goddi , L. Moscadelli , W. Alef , A. Tarchi , J. Brand , M. Pani