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Related papers: Powerful Water Masers in Active Galactic Nuclei

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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…

The study of water masers at cosmological distances would allow us to investigate the parsec-scale environment around powerful radio sources, to probe the physical conditions of the molecular gas in the inner parsecs of quasars, and to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 P. Castangia , C. M. V. Impellizzeri , J. P. McKean , C. Henkel , A. Brunthaler , A. L. Roy , O. Wucknitz , J. Ott , E. Momjian

The changes in the spectral line profile of the 22GHz H2O maser are calculated as a function of emerging maser flux. We address not only the narrowing and re-broadening of the maser lines, but also the deviations of Gaussian symmetry as a…

Astrophysics · Physics 2009-11-10 W. H. T. Vlemmings , H. J. van Langevelde

The nuclear gas kinematics probed by water vapor maser emission has shown that two nearby active galaxies, NGC 1068 and NGC 4258, have a supermassive object in their nuclei and their masses are nearly comparable; a few 10^7 solar masses.…

Astrophysics · Physics 2015-06-24 Takashi Murayama , Yoshiaki Taniguchi

The 25 years following the serendipitous discovery of megamasers have seen tremendous progress in the study of luminous extragalactic H$_2$O emission. Single-dish monitoring and high resolution interferometry have been used to identify…

Astrophysics · Physics 2009-11-10 C. Henkel , J. A. Braatz , A. Tarchi , A. B. Peck , N. M. Nagar , L. J. Greenhill , M. Wang , Y. Hagiwara

We present new maser emission from ^{14}NH_3 (9,6) in NGC 7538. Our observations include the known spectral features near v_LSR = -60 km/s and -57 km/s and several more features extending to -46 km/s. In three epochs of observation spanning…

Astrophysics of Galaxies · Physics 2015-05-30 Ian M. Hoffman , Stella Seojin Kim

We intended to study the incidence and characteristics of water masers in the envelopes of stars in the post-AGB and PN evolutionary stages. We have used the 64-m antenna in Parkes (Australia) to search for water maser emission at 22 GHz,…

Solar and Stellar Astrophysics · Physics 2015-05-13 O. Suárez , J. F. Gómez , L. F. Miranda , J. M. Torrelles , Y. Gómez , G. Anglada , O. Morata

We have observed 150 regions of massive star formation, selected originally by the presence of a water maser, in the J = 5-4, 3-2, and 2-1 transitions of CS, and 49 regions in the same transitions of C$^{34}$S. Over 90% of the 150 regions…

Astrophysics · Physics 2011-05-25 Rene Plume , D. T. Jaffe , Neal J. Evans , J. Martin-Pintado , J. Gomez-Gonzalez

We compare the number of detected 22 GHz H2O masers in the Local Group galaxies M31, M33, NGC6822, IC10, IC1613, DDO187, GR8, NGC185, and the Magellanic Clouds with the water maser population of the Milky Way. To accomplish this we searched…

Astrophysics · Physics 2009-11-11 A. Brunthaler , C. Henkel , W. J. G. de Blok , M. J. Reid , L. J. Greenhill , H. Falcke

Long-slit optical emission-line spectra of the H2O megamaser galaxies ESO 103-G03, TXS 2226-184, and IC 1481 are evaluated in order to look for characteristics typical for water-megamaser galaxies. We present rotation curves, line ratios,…

Astrophysics · Physics 2009-11-10 Nicola Bennert , Hartmut Schulz , Christian Henkel

A search for water masers in 47 Sloan Digital Sky Survey Type 2 quasars using the Green Bank Telescope has yielded a detection at a redshift of z = 0.660. This maser is more than an order of magnitude higher in redshift than any previously…

Astrophysics · Physics 2009-11-11 Richard Barvainis , Robert Antonucci

An astrophysical MASER (Microwave Amplification by Stimulated Emission of Radiation) is a source of stimulated spectral line emission. Maser emission is observed from the circumstellar envelopes of evolved stars, molecular…

Instrumentation and Methods for Astrophysics · Physics 2011-04-13 Elizabeth Humphreys

We report the detection of emission from the 6.7 GHz 5(1)-6(0)A+ transition of methanol towards the center of the nearby galaxy NGC4945. This is the first detection of emission in this transition beyond the local group. The isotropic…

Astrophysics of Galaxies · Physics 2018-10-25 Simon Ellingsen , Tiege McCarty , Shari Breen , Maxim Voronkov

Using the Submillimeter Array (SMA) we have imaged for the first time the 321.226 GHz, 10_{29}-9_{36} ortho-H2O maser emission. This is also the first detection of this line in the Cepheus A high-mass star-forming region. The 22.235 GHz,…

Astrophysics · Physics 2009-11-13 N. A. Patel , S. Curil , Q. Zhang , T. K. Sridharan , P. T. P. Ho , J. M. Torrelles

Several rotational transitions of water have been identified toward evolved stars in the ground vibrational state as well as in the first excited state of the bending mode. In the latter vibrational state of water, the 658 GHz J =…

Solar and Stellar Astrophysics · Physics 2017-12-27 A. Baudry , E. M. L. Humphreys , F. Herpin , K. Torstensson , W. H. T. Vlemmings , A. M. S. Richards , M. D. Gray , C. De Breuck , M. Olberg

We carried out observations of the 22 GHz H2O masers in a high-mass protostar S255 NIRS 3 by using VERA. We measured the proper motions of the 22 GHz H2O masers associated with a bipolar outflow. The expansion velocity of the blueshifted…

We have used the Australia Telescope Compact Array (ATCA) to make new observations of the 36.2-GHz ($4_{-1}\rightarrow3_0$E) methanol transition toward NGC 4945 and NGC 253. These observations have revealed the presence of new maser…

Astrophysics of Galaxies · Physics 2021-10-20 Tiege McCarthy , Simon Ellingsen , Shari Breen , Maxim Voronkov , Xi Chen , Hai-Hua Qiao

We report the results of a multi-epoch survey of water maser observations at 22.2 GHz with the Medicina radiotelescope from 44 bright rimmed clouds (BRCs) of the northern hemisphere identified by Sugitani et al. (1989) as potential sites of…

Astrophysics · Physics 2009-11-11 R. Valdettaro , F. Palla , J. Brand , R. Cesaroni

We present Expanded Very Large Array and Arecibo observations of two lensed submm galaxies at z~2.5, in order to search for redshifted 22.235 GHz water megamaser emission. Both SMM J14011+0252 and SMM J16359+6612 have multi-wavelength…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Jeff Wagg , Emmanuel Momjian

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
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