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Related papers: The Megamaser Cosmology Project: I. VLBI observati…

200 papers

Observations of H$_2$O masers towards the post-AGB star and water fountain source OH 009.1--0.4 were made as part of HOPS (The H$_2$O southern galactic Plane Survey), with the Mopra radiotelescope. Together with followup observations using…

Astrophysics · Physics 2008-12-11 A. J. Walsh , S. L. Breen , I. Bains , W. H. T. Vlemmings

We compare multi-epoch sub-arcsecond VLA imaging of the 22 GHz water masers toward the massive protocluster NGC6334I observed before and after the recent outburst of MM1B in (sub)millimeter continuum. Since the outburst, the water maser…

Solar and Stellar Astrophysics · Physics 2018-10-24 C. L. Brogan , T. R. Hunter , C. J. Cyganowski , J. O. Chibueze , R. K. Friesen , T. Hirota , G. C. MacLeod , B. A. McGuire , A. M. Sobolev

We present VLBA observations of water maser emission associated with the star-forming region IRAS 21391+5802, which is embedded in a bright rimmed cometary globule in IC1396. The angular resolution of the maps is about 0.8 mas,…

We present stellar kinematics and orbit superposition models for the central regions of four Brightest Cluster Galaxies (BCGs), based upon integral-field spectroscopy at Gemini, Keck, and McDonald Observatories. Our integral-field data span…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Nicholas J. McConnell , Chung-Pei Ma , Jeremy D. Murphy , Karl Gebhardt , Tod R. Lauer , James R. Graham , Shelley A. Wright , Douglas O. Richstone

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

Luminous water maser emission in the 6_(16)-5_(23) line at 22 GHz has been detected from two dozen galaxies. In all cases the emission is confined to the nucleus and has been found only in AGN, in particular, in Type 2 Seyferts and LINERs.…

Astrophysics · Physics 2009-11-07 Philip R. Maloney

The present paper focuses on the high-mass star-forming region G23.01-0.41. Methods: Using the VLBA and the EVN arrays, we conducted phase-referenced observations of the three most powerful maser species in G23.01-0.41: 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 explore the warm molecular and ionized gas in the centers of two megamaser disk galaxies using K-band spectroscopy. Our ultimate goal is to determine how gas is funneled onto the accretion disk, here traced by megamaser spots on sub-pc…

Astrophysics of Galaxies · Physics 2015-06-19 Jenny E. Greene , Anil Seth , Mariya Lyubenova , Jonelle Walsh , Glenn van de Ven , Ronald Laesker

As part of the mm-Wave Interferometric Survey of Dark Object Masses (WISDOM), we present a measurement of the mass of the supermassive black hole (SMBH) in the nearby early-type galaxy NGC 0383 (radio source 3C 031). This measurement is…

We report new precision measurements of the properties of our Galaxy's supermassive black hole. Based on astrometric (1995-2007) and radial velocity (2000-2007) measurements from the W. M. Keck 10-meter telescopes, a fully unconstrained…

We present a measurement of the supermassive black hole (SMBH) mass of the nearby lenticular galaxy NGC 383, based on Atacama Large Millimeter/sub-millimeter Array (ALMA) observations of the $^{12}$CO(2-1) emission line with an angular…

In this talk I will summarize some of the work that the CfA group has done to study the structure of the water masers in the accretion disk of NGC 4258. A series of 18 epochs of VLBA data taken from 1997.3 to 2000.8 were used for this…

Astrophysics · Physics 2008-04-08 James M. Moran

We report on the presence of 6.7-GHz methanol masers, known tracers of high-mass star formation, in the 3-kpc arms of the inner Galaxy. We present 49 detections from the Methanol Multibeam Survey, the largest Galactic plane survey for…

Astrophysics of Galaxies · Physics 2009-04-29 J. A. Green , N. M. McClure-Griffiths , J. L. Caswell , S. P. Ellingsen , G. A. Fuller , L. Quinn , M. A. Voronkov

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 study the optical properties of the host galaxies of nuclear 22 GHz (lambda=1.35 cm) water masers. To do so, we cross-match the galaxy sample surveyed for water maser emission (123 detections and 3806 non-detections) with the SDSS…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Guangtun Zhu , Ingyin Zaw , Michael R. Blanton , Lincoln J. Greenhill

Large column densities, derived from X-ray studies, are typically measured towards AGN hosting water masers, especially when the H2O emission is associated with the nuclear accretion disk. In addition, possible correlations between the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 P. Castangia , F. Panessa , C. Henkel , M. Kadler , A. Tarchi

We present first results of the H_2O Southern Galactic Plane Survey (HOPS), using the Mopra radiotelescope with a broad band backend and a beam size of about 2'. We have observed 100 square degrees of the southern Galactic plane at 12mm…

We present an analysis of polarimetric observations at 22 GHz of the water vapor masers in NGC 4258 obtained with the VLA and the GBT. We do not detect any circular polarization in the spectrum indicative of Zeeman-induced splitting of the…

Astrophysics · Physics 2009-11-10 Maryam Modjaz , James M. Moran , Paul T. Kondratko , Lincoln J. Greenhill

We present 321 GHz observations of five AGN from ALMA Cycle 0 archival data: NGC 5793, NGC 1068, NGC 1386, NGC 4945, and the Circinus galaxy. Submillimeter maser emission is detected for the first time towards NGC 4945, and we present a new…

Astrophysics of Galaxies · Physics 2016-08-17 D. W. Pesce , J. A. Braatz , C. M. V. Impellizzeri

We aim to explore the relationship between globular cluster total number, $N_{\rm GC}$, and central black hole mass, $M_\bullet$, in spiral galaxies, and compare it with that recently reported for ellipticals. We present results for the Sbc…

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