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Related papers: Water masers in dusty environments

200 papers

We present the results of models that were designed to study all possible water maser transitions in the frequency range 0-1.91THz, with particular emphasis on maser transitions that may be generated in evolved-star envelopes and observed…

Astrophysics of Galaxies · Physics 2015-11-19 M. D. Gray , A. Baudry , A. M. S. Richards , E. M. L. Humphreys , A. M. Sobolev , J. A. Yates

OH megamasers (OHMs) emit primarily in the main lines at 1667 and 1665 MHz, and differ from their Galactic counterparts due to their immense luminosities, large linewidths and 1667/1665 MHz flux ratios, which are always greater than one. We…

Astrophysics · Physics 2009-11-13 Philip Lockett , Moshe Elitzur

We study the conditions for operation of the 22 GHz ortho-water maser in a dusty medium near late-type stars. The main physical processes, such as exchange of energy between dust and gas in the radiation field of a star, radiative cooling…

Astrophysics · Physics 2009-11-13 Natalia Babkovskaia , Juri Poutanen

The 4.8 GHz formaldehyde masers are one of a number of rare types of molecular masers in the Galaxy. The aim of the present calculations is to explore a larger region of parameter space to improve on our previous calculations, thereby to…

Astrophysics of Galaxies · Physics 2022-01-19 D. J. van der Walt , L. L. Mfulwane

We have conducted a sensitive water maser search with the ATCA towards 267 1.2-mm dust clumps presented in the literature. We combine our new observations with previous water maser observations to extend our sample to 294 1.2-mm dust…

Astrophysics of Galaxies · Physics 2015-05-28 Shari Breen , Simon Ellingsen

The ATCA has been used to measure positions with arcsecond accuracy for 379 masers at the 22-GHz transition of water. The principal observation targets were 202 OH masers of the variety associated with star formation regions (SFR)s in the…

Astrophysics of Galaxies · Physics 2015-05-18 Shari Breen , James Caswell , Simon Ellingsen , Chris Phillips

Using the Herschel Space Observatory's Heterodyne Instrument for the Far-Infrared (HIFI), we have performed mapping observations of the 620.701 GHz 5(32)-4(41) transition of ortho-H2O within a roughly 1.5 x 1.5 arcmin region encompassing…

Astrophysics of Galaxies · Physics 2015-06-15 David A. Neufeld , Yuanwei Wu , Alex Kraus , Karl M. Menten , Volker Tolls , Gary J. Melnick , Zsofia Nagy

The collisional pumping of H_2^{16}O and H_2^{18}O masers in hot dense gas-dust clouds has been simulated numerically. New data on the rate coefficients for collisional transitions from Faure et al. (2007) were used in the calculations. The…

High Energy Astrophysical Phenomena · Physics 2011-07-19 Aleksandr Nesterenok , Dmitry Varshalovich

Water masers are common in star-forming regions (SFRs), with the 22.235 GHz transition widely detected in both high- and low-mass protostars. In contrast, (sub)millimeter water maser transitions remain poorly studied, especially in low-mass…

Astrophysics of Galaxies · Physics 2025-09-17 P. K. Humire , C. Goddi , G. N. Ortiz-León , A. Hernández-Gómez , J-C Loison

The Australia Telescope Compact Array has been used to search for 22-GHz water masers towards the 119 6.7-GHz methanol masers detected in the Methanol Multi-Beam survey between Galactic longitudes 6 and 20 degrees; we find water masers…

Solar and Stellar Astrophysics · Physics 2015-06-22 A. M. Titmarsh , S. P. Ellingsen , S. L. Breen , J. L. Caswell , M. A. Voronkov

Context. Water vapor emission at 22 GHz from masers associated with star-forming regions is highly variable. Aims. We present a database of up to 20 years of monitoring of a sample of 43 masers within star-forming regions. The sample covers…

Here we aim to characterise submillimetre water masers at 437, 439, 471, and 474 GHz towards a sample of evolved stars. We used the Atacama Pathfinder Experiment (APEX) to observe submillimetre water transitions and the CO (4-3) line…

Solar and Stellar Astrophysics · Physics 2020-05-27 P. Bergman , E. M. L. Humphreys

We report detection of moderate to high-mass star formation in an infrared dark cloud (G11.11-0.12) where we discovered class II methanol and water maser emissions at 6.7 GHz and 22.2 GHz, respectively. We also observed the object in…

Astrophysics · Physics 2009-11-13 Thushara Pillai , Friedrich Wyrowski , Karl M. Menten , Endrik Kr"ugel

We present the rest-frame 200--320 \mm\ spectrum of the z=3.91 quasar \apm, obtained with Z-Spec at the Caltech Submillimeter Observatory. In addition to the \jeight\ to \jthirteen\ CO rotational transitions which dominate the CO cooling,…

We present a comparison of Spitzer IRS data for 51 OH megamaser (OHM) hosts and 15 non-masing ULIRGs. 10-25% of OHMs show evidence for the presence of an AGN, significantly lower than the estimated AGN fraction from previous optical and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Kyle W. Willett , Jeremy Darling , Henrik W. W. Spoon , Vassilis Charmandaris , Lee Armus

We report the first detection of submillimeter water maser emission toward water-fountain nebulae, which are post-AGB stars that exhibit high-velocity water masers. Using APEX we found emission in the ortho-H2O (10_29-9_36) transition at…

Solar and Stellar Astrophysics · Physics 2015-06-18 D. Tafoya , R. Franco-Hernández , W. H. T. Vlemmings , A. F. Pérez-Sánchez , G. Garay

We investigate the kinematics of high mass protostellar objects within the high mass star forming region IRAS 19410+2336. We performed high angular resolution observations of 6.7-GHz methanol and 22 GHz water masers using the MERLIN…

Astrophysics of Galaxies · Physics 2021-05-25 M. S. Darwish , K. A. Edris , A. M. S. Richards , S. Etoka , M. S. Saad , M. M. Beheary , G. A Fuller

The collisional pumping of CH3OH and OH masers in non-dissociative C-type shock waves is studied. The chemical processes responsible for the evolution of molecule abundances in the shock wave are considered in detail. The large velocity…

Astrophysics of Galaxies · Physics 2021-12-15 A. V. Nesterenok

The study of warm molecular gas in the inner regions of protoplanetary disks is of key importance for the study of planet formation and especially for the transport of H2O and organic molecules to the surfaces of rocky planets/satellites.…

Earth and Planetary Astrophysics · Physics 2014-11-20 R. Meijerink , K. M. Pontoppidan , G. A. Blake , D. R. Poelman , C. P. Dullemond
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