English
Related papers

Related papers: Powerful Water Masers in Active Galactic Nuclei

200 papers

The present paper focuses on the high-mass star-forming region G16.59-0.05. Methods: Using the VLBA and the EVN arrays, we conducted phase-referenced observations of the three most powerful maser species in G16.59-0.05: H2O at 22.2 GHz (4…

Astrophysics of Galaxies · Physics 2015-05-18 A. Sanna , L. Moscadelli , R. Cesaroni , A. Tarchi , R. S. Furuya , C. Goddi

We performed a systematic 6.7 GHz Class \uppercase\expandafter{\romannumeral2} methanol maser survey using the Shanghai Tianma Radio Telescope toward targets selected from the all-sky \emph{Wide-Field Infrared Survey Explorer (WISE)} point…

Astrophysics of Galaxies · Physics 2019-04-30 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 , Zhiyuan Ren

We report R~3000 VLT ISAAC K-band spectroscopy of the nuclei (i.e. central 100-300pc) of 9 galaxies hosting an active galactic nucleus. For 5 of these we also present spectra of the circumnuclear region out to 1kpc. We have measured a…

Astrophysics · Physics 2009-11-13 R. I. Davies , A. Sternberg , M. D. Lehnert , L. E. Tacconi-Garman

An Australia Telescope Compact Array search for 22 GHz water masers towards 6.7 GHz class II methanol masers detected in the Methanol Multibeam (MMB) survey has resulted in the detection of extremely high velocity emission from one of the…

Astrophysics of Galaxies · Physics 2015-06-16 A. M. Titmarsh , S. P. Ellingsen , S. L. Breen , J. L. Caswell , M. A. Voronkov

Radiative transfer equations are derived and solved for the stimulated Raman scattering of water maser lines in the astrophysical plasmas with electron density of about 10^6 - 10^7 cm-3. In stimulated Raman scattering, the energy of water…

Astrophysics · Physics 2009-10-31 R. T. Gangadhara , Shuji Deguchi , H. Lesch

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…

We present the results of single-dish and VLBI observations for the water-vapor masers at the nucleus of the Seyfert 2, IC 2560. We monitored velocities of the maser features with the 45-m telescope of the Nobeyama Radio Observatory. Using…

Astrophysics of Galaxies · Physics 2015-06-05 Aya Yamauchi , Naomasa Nakai , Yuko Ishihara , Philip Diamond , Naoko Sato

We test models of starburst driven outflows using observations of the 22.2 GHz H$_2$O and 36.2 GHz class I CH$_3$OH maser lines. We have observed the starburst galaxy NGC 253 using the Karl G. Jansky Very Large Array. We present evidence…

Astrophysics of Galaxies · Physics 2019-01-16 Mark Gorski , Jürgen Ott , Richard Rand , David S. Meier , Emmanuel Momjian , Eva Schinnerer , Simon P. Ellingsen

Calculations are performed to demonstrate the deviations from Gaussian that occur in the spectral line profiles of a linear maser as a result of the amplification process. Near-Gaussian profiles are presented for bright, interstellar 22 GHz…

Astrophysics · Physics 2009-11-07 W. D. Watson , A. P. Sarma , M. S. Singleton

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

Ejection activities in S255IR-SMA1 and AFGL 5142 were investigated by multi-epoch VLBI observations of 22 GHz water masers, tracing bowshocks leading collimated jets. The history of ejections, revealed by the 3D maser motions and…

Solar and Stellar Astrophysics · Physics 2018-08-22 Ross A. Burns

Observations of H$_2$O masers from circumnuclear disks in active galaxies for the Megamaser Cosmology Project allow accurate measurement of the mass of supermassive black holes (BH) in these galaxies. We present the Very Long Baseline…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 C. Y. Kuo , J. A. Braatz , J. J. Condon , C. M. V. Impellizzeri , K. Y. Lo , I. Zaw , M. Schenker , C. Henkel , M. J. Reid , J. E. Greene

The first VLBI images of water maser emission in the Circinus Galaxy AGN show both a warped, edge-on accretion disk and an outflow 0.1 to 1 pc from the central engine. The inferred central mass is 1.3 million suns, while the disk mass may…

A 22 GHz water maser survey was conducted towards 178 O-rich AGB stars with the aim of identifying maser emission associated with the Sagittarius stellar stream. In this survey, maser emissions were detected in 21 targets, of which 20 were…

Astrophysics of Galaxies · Physics 2022-09-14 Yuanwei Wu , Bo Zhang , Jingjing Li , Xing-Wu Zheng

Masers are a unique tool to investigate the emitting gas in the innermost regions of AGNs and to map accretion disks and tori orbiting around supermassive black holes. IC485, which is classified as a LINER or Seyfert galaxy, hosts a bright…

Astrophysics of Galaxies · Physics 2024-01-31 E. Ladu , A. Tarchi , P. Castangia , G. Surcis , J. A. Braatz , F. Panessa , D. Pesce

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

We report measurements of centripetal accelerations of maser spectral components of NGC 4258 for 51 epochs spanning 1994 to 2004. This is the second paper of a series, in which the goal is determination of a new geometric maser distance to…

Astrophysics · Physics 2009-11-13 E. M. L. Humphreys , M. J. Reid , L. J. Greenhill , J. M. Moran , A. L. Argon

We present the results of ALMA band-5 (~170 GHz) observations of the merging ultraluminous infrared galaxy, the "Superantennae" (IRAS 19254-7245) at z=0.0617, which has been diagnosed as containing a luminous obscured active galactic…

Astrophysics of Galaxies · Physics 2021-02-03 Masatoshi Imanishi , Yoshiaki Hagiwara , Shinji Horiuchi , Takuma Izumi , Kouichiro Nakanishi

We present the third instalment of a series of catalogues presenting 12.2-GHz methanol maser observations made towards each of the 6.7-GHz methanol masers detected in the Methanol Multibeam (MMB) Survey. The current portion of the catalogue…

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