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Related papers: OH and H2O maser variations in W33B

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We report on observations of the hydroxyl radical (OH) within The H{\sc I}, OH Recombination line survey (THOR) pilot region. The region is bounded approximately between Galactic coordinates l=29.2 to 31.5$^\circ$ and b=-1.0 to +1.0$^\circ$…

The Ultra Luminous InfraRed Galaxy Mrk 231 reveals up to seven rotational lines of water (H2O) in emission, including a very high-lying (E_{upper}=640 K) line detected at a 4sigma level, within the Herschel/SPIRE wavelength range, whereas…

(Pseudo) radiative pumprate of OH 1612 MHz masers is defined for a sample of 44 OH/IR sources (infrared sources with OH 1612 MHz maser), irrespective of the real maser pumping mechanisms. The correlation between the (pseudo) maser pumprates…

Astrophysics · Physics 2007-05-23 J. H. He

In the spectra of pulsating stars, especially Mira stars, the detection of intense hydrogen emission lines has been explained by a radiative shock wave, periodically propagating throughout the atmosphere. Previous observation of the Mira…

Solar and Stellar Astrophysics · Physics 2011-09-30 Nicolas Fabas , Agnès Lèbre , Denis Gillet

Mapping and monitoring observations of SiO maser sources near the Galactic center were made with the Nobeyama 45-m telescope at 43 GHz. Rectangular mapping an area of approximately 200'' x 100''$ in a 30'' grid, and triangular mapping in a…

Astrophysics · Physics 2015-06-24 Shuji Deguchi , Takahiro Fujii , Makoto Miyoshi , Jun-ichi Nakashima

We present a survey of the polarization properties of mm-wavelength methanol masers, comprising both classes, and transitions from 84.5 to 157.0 GHz. Linear polarization is found in more than half of the observed objects, and circular…

Astrophysics · Physics 2009-11-10 Helmut Wiesemeyer , Clemens Thum , Malcolm Walmsley

Context. Class II methanol masers at 6.7 and 12.2 GHz occur close to high-mass young stellar objects (HMYSOs). When they are observed simultaneously, such studies may contribute to refining the characterisation of local physical conditions.…

Astrophysics of Galaxies · Physics 2021-04-28 M. Durjasz , M. Szymczak , P. Wolak , A. Bartkiewicz

Observations of the four $^{2}\Pi_{3/2},~J = 3/2$~ground state transitions of the hydroxyl radical (OH) have emerged as an informative tracer of molecular gas in the Galactic ISM. We discuss an OH spectral feature known as the `flip', in…

Astrophysics of Galaxies · Physics 2020-08-12 Anita Petzler , Joanne R Dawson , Mark Wardle

We report on the detection and analysis of hot ro-vibrational H2O emission from SVS-13, a young stellar object previously known to have strong CO overtone bandhead emission. Modeling of the high-resolution infrared spectrum shows that the…

Astrophysics · Physics 2009-11-10 John S. Carr , Alan T. Tokunaga , Joan Najita

Magnetic fields have only recently been included in theoretical simulations of high-mass star formation. The simulations show that magnetic fields play an important role in the formation and dynamics of molecular outflows. Masers, in…

Solar and Stellar Astrophysics · Physics 2015-06-16 G. Surcis , W. H. T. Vlemmings , H. J. van Langevelde , B. Hutawarakorn Kramer , L. H. Quiroga-Nunez

Aims: We have observed the 6030 and 6035 MHz transitions of OH in high-mass star-forming regions to obtain magnetic field estimates in both maser emission and absorption. Methods: Observations were taken with the Effelsberg 100 m telescope.…

Astrophysics · Physics 2009-11-11 Vincent L. Fish , Mark J. Reid , Karl M. Menten , Thushara Pillai

We have monitored the SiO (v = 1, J = 2 -> 1) maser polarization in 17 variable stars (Miras, OH-IR stars, and supergiants) to investigate the long-term persistence of masers. The 8 epochs of observations span 2.5 years, thereby sampling…

Astrophysics · Physics 2008-11-26 Jason Glenn , Philip R. Jewell , Remy Fourre , Luis Miaja

We present full-polarization VLBA maps of the ground-state, main-line, 2 Pi 3/2, J = 3/2 OH masers in 18 Galactic massive star-forming regions. This is the first large polarization survey of interstellar hydroxyl masers at VLBI resolution.…

Astrophysics · Physics 2009-11-11 Vincent L. Fish , Mark J. Reid , Alice L. Argon , Xing-Wu Zheng

We present the results of unbiased 22 GHz H2O water and 44 GHz class I CH3OH methanol maser surveys in the central 7x10 arcmin area of NGC 1333 and two additional mapping observations of a 22 GHz water maser in a ~3x3arcmin area of the…

Astrophysics of Galaxies · Physics 2015-06-22 A-Ran Lyo , Jongsoo Kim , Do-Young Byun , Ho-Gyu Lee

We report new observations of the H2O megamaser in the Seyfert 2 galaxy Mrk 348. Following our initial detection in 2000 March using the Effelsberg 100 m telescope, re-analysis of previous data on this source indicates that the maser was…

Astrophysics · Physics 2007-05-23 A. B. Peck , H. Falcke , C. Henkel , K. M. Menten , Y. Hagiwara , J. F. Gallimore , J. S. Ulvestad

Water is an important molecule in interstellar and circumstellar environments. Previous observations of mid-infrared rotational lines of OH suggest that these lines may be used to probe the photodissociation of water. In this work, cross…

Astrophysics of Galaxies · Physics 2021-06-30 Benoît Tabone , Marc C. van Hemert , Ewine F. van Dishoeck , John H. Black

We present near-infrared and millimetre-line observations of the Tornado nebula (G357.7-0.1). We detected 2.12 micron_m H2 1-0 S(1) line emission towards the suspected site of interaction with a molecular cloud revealed by the presence of…

Astrophysics · Physics 2009-11-10 J. S. Lazendic , M. Wardle , M. G. Burton , F. Yusef-Zadeh , A. J. Green , J. B. Whiteoak

Stimulated emission of radiation has not been directly observed in astrophysical situations up to this time. Here we demonstrate that photons from pulsar B1641-45 stimulate pulses of excess 1720 MHz line emission in an interstellar OH…

Astrophysics · Physics 2009-11-11 Joel M. Weisberg , Simon Johnston , Baerbel Koribalski , Snezana Stanimirovic

HMYSOs gain most of their mass in short bursts of accretion. Maser emission is an invaluable tool in discovering and probing accretion bursts. We observed the 22 GHz water maser response induced by the accretion burst in NGC6334I-MM1B and…

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