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Related papers: 183 GHz water megamasers in active galactic nuclei…

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We report simultaneous single-dish surveys of 22 GHz H2O and 44 and 95 GHz class I CH3OH masers toward 299 Red MSX Sources in the protostellar stage. The detection rates are 45% at 22 GHz, 28% at 44 GHz, and 23% at 95 GHz. There are 15, 53,…

Astrophysics of Galaxies · Physics 2018-05-23 Chang-Hee Kim , Kee-Tae Kim , Yong-Sun Park

We report on Green Bank Telescope 23.87 GHz NH$_3$(3,3), emission observations in five supernova remnants interacting with molecular clouds (G1.4$-$0.1, IC443, W44, W51C, and G5.7$-$0.0). The observations show a clumpy gas density…

Astrophysics of Galaxies · Physics 2016-08-17 Bridget McEwen , Ylva Pihlström , Loránt Sjouwerman

We report the results of our systematic survey for Galactic 6.7 GHz Class II CH$_3$OH maser emission toward a sample of young stellar objects. The survey was conducted with the Shanghai Tianma Radio Telescope (TMRT). The sample consists of…

Astrophysics of Galaxies · Physics 2019-06-14 Kai Yang , Xi Chen , Zhi-Qiang Shen , Xiao-Qiong Li , Jun-Zhi Wang , Dong-Rong Jiang , Juan Li , Jian Dong , Ya-Jun Wu , Hai-Hua Qiao

Submillimetre-selected galaxies (SMGs) at high redshift ($z$ $\sim$ 2) are potential host galaxies of active galactic nuclei (AGN). If the local Universe is a good guide, $\sim$ 50$\%$ of the obscured AGN amongst the SMG population could be…

Active Galactic Nuclei (AGNs) hosting disk water megamasers are well known to be obscured by large amounts of gas, likely due to the presence along the line of sight of an almost edge-on disky structure orbiting the supermassive black hole.…

High Energy Astrophysical Phenomena · Physics 2019-09-11 Alberto Masini , Andrea Comastri , Ryan C. Hickox , Michael Koss , Francesca Civano , Murray Brightman , Marcella Brusa , Giorgio Lanzuisi

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

The University of Tasmania Mt Pleasant 26-m and Ceduna 30-m radio telescopes have been used to search for 6.7-GHz class II methanol masers towards two hundred GLIMPSE sources. The target regions were selected on the basis of their…

Astrophysics · Physics 2008-11-26 S. P. Ellingsen

Recently, a relationship between the water maser detection rate and far infrared (FIR) flux density has been found as a result of a 22 GHz maser survey in a sample comprised of northern galaxies with 100 micron flux density > 50 Jy and a…

Astrophysics · Physics 2007-12-06 P. Castangia , A. Tarchi , C. Henkel , K. M. Menten

We present the results of studies of a new class of 6.7 GHz methanol maser sources with a ring-like emission structure discovered recently with the EVN. We have used the VLA to search for water masers at 22 GHz and radio continuum at 8.4…

Astrophysics of Galaxies · Physics 2015-03-18 A. Bartkiewicz , M. Szymczak , H. J. van Langevelde , J. M. De Buizer , Y. Pihlström

We report the results of a search for class II methanol masers at 37.7, 38.3 and 38.5 GHz towards a sample of 70 high-mass star formation regions. We primarily searched towards regions known to show emission either from the 107 GHz class II…

Astrophysics of Galaxies · Physics 2015-05-30 S. P. Ellingsen , S. L. Breen , A. M. Sobolev , M. A. Voronkov , J. L. Caswell , N. Lo

We report the first sub-arcsecond VLA imaging of 6 GHz continuum, methanol maser, and excited-state hydroxyl maser emission toward the massive protostellar cluster NGC6334I following the recent 2015 outburst in (sub)millimeter continuum…

We perform a census of ionized gas outflows using a sample of ~23,000 type 2 active galactic nuclei (AGNs) out to z~0.1. By measuring the velocity offset of narrow emission lines, i.e., [O III] {\lambda}5007 and H{\alpha}, with respect to…

Astrophysics of Galaxies · Physics 2014-10-14 Hyun-Jin Bae , Jong-Hak Woo

We derive kinematic distances to the 86 6.7 GHz methanol masers discovered in the Arecibo Methanol Maser Galactic Plane Survey. The systemic velocities of the sources were derived from 13CO (J=2-1), CS (J=5-4), and NH3 observations made…

Astrophysics of Galaxies · Physics 2014-11-20 J. D. Pandian , K. M. Menten , P. F. Goldsmith

We present a new investigation of the dependence of H2O maser detection rates and properties on the mid-IR AGN luminosity, L_AGN, and the obscuring column density, N_H, based on mid-IR and hard X-ray photometry. Based on spectral energy…

We revisit the relation between H2O maser detection rate and nuclear obscuration for a sample of 114 Seyfert galaxies, drawn from the CfA, 12um and IRAS F25/F60 catalogs. These sources have mid-infrared spectra from the Spitzer Space…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Michael Ramolla , Martin Haas , Vardha Nicola Bennert , Rolf Chini

We have conducted phase-reference multi-epoch observations of the 22.2 GHz water masers using the VLBA and multi-frequency study of the continuum emission using the VLA towards the high-mass SFR AFGL 5142. The water maser emission comes…

Astrophysics · Physics 2009-11-11 C. Goddi , L. Moscadelli

Galaxies often contain large reservoirs of molecular gas which shape their evolution. This can be through cooling of the gas -- which leads to star formation, or accretion onto the central supermassive black hole -- which fuels AGN activity…

Astrophysics of Galaxies · Physics 2022-11-16 Tom Rose , B. R. McNamara , F. Combes , A. C. Edge , A. C. Fabian , M. Gaspari , H. Russell , P. Salomé , G. Tremblay , G. Ferland

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

The high-mass star forming sites SgrB2(M) and SgrB2(N) have been the target of numerous studies, revealing e.g. a rich chemistry. We want to characterize their physical and chemical structure using ALMA high-angular resolution observations…

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…