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Related papers: Extragalactic H2O Masers

200 papers

High resolution maps of maser emission provide very detailed information on processes occurring in circumstellar envelopes of late-type stars. A particularly detailed picture of the innermost shells around AGB stars is provided by SiO…

Solar and Stellar Astrophysics · Physics 2009-06-02 Francisco Colomer

We describe a method to identify inclined water maser disks orbiting massive black holes and to potentially use them to measure black hole masses. Due to the geometry of maser amplification pathways, the minority of water maser disks are…

Astrophysics of Galaxies · Physics 2017-03-15 Jeremy Darling

Naturally occurring water vapor maser emission at 1.35 cm wavelength provides an accurate probe for the study of accretion disks around highly compact objects, thought to be black holes, in the centers of active galaxies. Because of the…

Astrophysics · Physics 2009-10-31 J. M. Moran , L. J. Greenhill , J. R. Herrnstein

Astrophysical masers are one of the most readily detected signposts of high-mass star formation. Their presence indicates special conditions, probably indicative of a specific evolutionary phase. Masers also represent the ultimate…

Astrophysics · Physics 2007-05-23 Simon Ellingsen

Interstellar masers are unique probes of the environments in which they arise. In studies of high-mass star formation their primary function has been as signposts of these regions and they have been used as probes of the kinematics and…

Astrophysics · Physics 2009-11-13 S. P. Ellingsen , M. A. Voronkov , D. M. Cragg , A. M. Sobolev , S. L. Breen , P. D. Godfrey

The near infrared (1-2um) and the thermal infrared (3-25um) trace many of the environments in which masers are thought to reside, including shocks, outflows, accretion disks, and the dense medium near protostars. After a number of recent…

Astrophysics · Physics 2009-11-13 James De Buizer

To place the highly substructured stellar halos of the Milky Way and M31 in a larger context of hierarchical galaxy formation, it is necessary to understand the prevalence and properties of tidal substructure around external galaxies. This…

Astrophysics of Galaxies · Physics 2016-03-23 Jeffrey L. Carlin , Rachael L. Beaton , David Martinez-Delgado , R. Jay Gabany

The intense line emission of OH masers is a perfect tracer of regions where new stars are born aswell as of evolved stars, shedding large amounts of processed matter into the interstellar medium. From SKA deep surveys at 18 cm, where the…

Solar and Stellar Astrophysics · Physics 2015-01-29 Sandra Etoka , Dieter Engels , Hiroshi Imai , Joanne Dawson , Simon Ellingsen , Lorant Sjouwerman , Huib van Langevelde

The Galactic Center contains large amounts of molecular and ionized gas as well as a plethora of energetic objects. Water masers are an extinction-insensitive probe for star formation and thus ideal for studies of star formation stages in…

Astrophysics of Galaxies · Physics 2018-08-22 Juergen Ott , Nico Krieger , Matthew Rickert , David S Meier , Adam Ginsburg , Farhad Yusef-Zadeh , the SWAG team

Stars at the top of the asymptotic giant branch (AGB) can exhibit maser emission from molecules like SiO, H2O and OH. As the star evolves to the planetary nebula phase, mass-loss stops and ionization of the envelope begins, making the…

Astrophysics · Physics 2008-01-21 Y. Gomez

Luminous extragalactic water masers are known to be associated with AGN and have provided accurate estimates for the mass of the central supermassive black hole and the size and structure of the accretion disk in nearby galaxies. To find…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 J. P. McKean , C. M. V. Impellizzeri , A. L. Roy , P. Castangia , F. Samuel , A. Brunthaler , C. Henkel , O. Wucknitz

One of the main themes in extragalactic astronomy for the next decade will be the evolution of galaxies over cosmic time. Many future observatories, including JWST, ALMA, GMT, TMT and E-ELT will intensively observe starlight over a broad…

We use unpublished and published VLBI results to investigate the geometry and the statistical properties of the velocity field traced by H2O masers in five galactic regions of star formation -- Sgr B2(M), W49N, W51(MAIN), W51N, and W3(OH).…

Astrophysics · Physics 2009-11-07 V. Strelnitski , J. Alexander , S. Gezari , B. P. Holder , J. M. Moran , M. J. Reid

This paper reviews recent advances in the study or circumstellar masers and masers found toward supernova remnants. The review is organized by science focus area, including the astrophysics of extended stellar atmospheres, stellar mass-loss…

Astrophysics · Physics 2009-11-13 Athol J. Kemball

This review covers selected developments in maser theory since the previous meeting, "Cosmic Masers: From Proto-Stars to Black Holes" (Migenes & Reid 2002). Topics included are time variability of fundamental constants, pumping of OH…

Astrophysics · Physics 2009-11-13 Moshe Elitzur

Atomic Hydrogen (HI) is a useful tracer of gas in and around galaxies, and can be found in extended disk-like structures well beyond a system's optical extent. Here we investigate the properties of extended HI disks that emerge in six Milky…

Ten years have passed since the global solutions of advective accretion disks around black holes and neutron stars were first discovered. Since then they are enjoying support from observers almost on a daily basis, more so in recent days…

Astrophysics · Physics 2007-05-23 S. K. Chakrabarti

We report four new 22 GHz water masers found in a Green Bank Telescope search toward 37 nearby objects. Our goal was to find new maser galaxies, AGN disk-masers, and objects where both hydroxyl and water maser species coexist. We observed…

Astrophysics of Galaxies · Physics 2015-06-17 J. Wagner

We present a comparative multi-wavelength analysis of water maser-emitting regions and non-maser-emitting luminous 24 micron star-forming regions in the Andromeda Galaxy (M31) to identify the sites most likely to produce luminous water…

Astrophysics of Galaxies · Physics 2016-08-03 Nikta Amiri , Jeremy Darling

We detected the H2O 6.3 micron bands in more than 30 normal red giants stars from K5III to M8III as well as in some early M supergiants on the SWS spectra retrieved from the ISO Data Archive. This result, however, shows serious…

Astrophysics · Physics 2007-05-23 Takashi Tsuji