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Related papers: Broad HI absorption in the candidate binary black-…

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We present the results of HI and OH absorption measurements towards a sample of radio sources using the Arecibo 305-m telescope and the GMRT. In total, 27 radio sources were searched for associated 21-cm HI absorption. One totally new HI…

Astrophysics · Physics 2009-11-11 Neeraj Gupta , C. J. Salter , D. J. Saikia , T. Ghosh , S. Jeyakumar

We present Giant Metrewave Radio Telescope and Very Large Array observations of HI 21-cm absorption in ten z<=0.2 galaxy mergers that host strong radio sources. Seven of these mergers show strong absorption [with N(HI) ~10^{21-22} cm^{-2},…

Astrophysics of Galaxies · Physics 2018-08-01 Rajeshwari Dutta , Raghunathan Srianand , Neeraj Gupta

We report the detection of 21-cm HI absorption towards the core of the Fanaroff-Riley II radio galaxy 3C452 (J2245+3941). The absorption profile is well resolved into three components; the strongest and narrowest component being coincident…

Astrophysics · Physics 2009-11-11 Neeraj Gupta , D. J. Saikia

SDSS J092712.65+294344.0 has been proposed as a candidate for a supermassive black hole (~10^8.8 solar masses) ejected at high speed from the host galactic nucleus by gravitational radiation recoil, or alternatively for a supermassive black…

Astrophysics · Physics 2011-02-11 G. A. Shields , E. W. Bonning , S. Salviander

Recent targeted studies of associated HI absorption in radio galaxies are starting to map out the location, and potential cosmological evolution, of the cold gas in the host galaxies of Active Galactic Nuclei (AGN). The observed 21 cm…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 J. R. Allison , E. M. Sadler , S. J. Curran , S. N. Reeves

We report a new, rare detection of HI 21-cm absorption associated with a quasar (only six known at $1<z<2$) here towards J2339-5523 at $z_{em}$ = 1.3531, discovered through the MeerKAT Absorption Line Survey (MALS). The absorption profile…

We have used the visible integral-field replicable unit spectrograph prototype (VIRUS-P), a new integral field spectrograph, to study the spatially and spectrally resolved Lyman-alpha emission line structure in the radio galaxy B2 0902+34…

Astrophysics · Physics 2014-11-18 Joshua J Adams , Gary J. Hill , Phillip J. MacQueen

MAXI J1305-704 has been proposed as a high-inclination candidate black hole X-ray binary in view of its X-ray properties and dipping behaviour during outburst. We present photometric and spectroscopic observations of the source in…

High Energy Astrophysical Phenomena · Physics 2021-06-30 D. Mata Sánchez , A. Rau , A. Álvarez Hernández , T. F. J. van Grunsven , M. A. P. Torres , P. G. Jonker

We present results of a comprehensive multi-frequency study of the radio galaxy B3 J2330+3927. The 1.9" wide radio source, consisting of 3 components, is bracketed by 2 objects in our Keck K-band image. Optical and near-IR Keck spectroscopy…

We report the detection of OH 1667 MHz and wide HI 21cm absorption at $z \sim 0.67$ towards the red quasar 1504+377, with the Green Bank Telescope and the Giant Metrewave Radio Telescope. The HI 21cm absorption extends over a velocity range…

Astrophysics · Physics 2009-11-13 Nissim Kanekar , Jayaram N. Chengalur

We searched for 21-cm absorption associated with the z_abs = 1.3647 absorption system toward PKS 0237-233 using the GMRT. A high quality UVES spectrum shows that C I and C I* are detected at this redshift together with C II*, Mg I, Mg II,…

Astrophysics · Physics 2008-11-26 Raghunathan Srianand , Neeraj Gupta , Patrick Petitjean

We present the results of HI absorption measurements towards a sample of nearby Compact Steep-Spectrum (CSS) and Giga-Hertz Peaked Spectrum (GPS) radio sources, the CORALZ sample, using the Giant Metrewave Radio Telescope (GMRT). We…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Yogesh Chandola , S. K. Sirothia , D. J. Saikia

The radio galaxy 0402+379 is believed to host a supermassive black hole binary (SMBHB). The two compact core sources are separated by a projected distance of 7.3 pc, making it the most (spatially) compact resolved SMBHB known. We present…

Astrophysics of Galaxies · Physics 2017-07-05 Karishma Bansal , Greg B. Taylor , Alison. B. Peck , Robert T. Zavala , Roger W. Romani

We report the first detections of associated H{\sc i} 21\,cm absorption in Gigahertz-peaked-spectrum (GPS) sources at high redshifts, $z > 1$, using the Giant Metrewave Radio Telescope (GMRT). Our GMRT search for associated H{\sc i} 21\,cm…

Astrophysics of Galaxies · Physics 2017-10-25 J. N. H. S. Aditya , Nissim Kanekar

We present global VLBI observations of the ~8100 km s$^{-1}$ HI absorption feature detected toward the strong radio nucleus 3C 84 of NGC 1275 in the Perseus cluster (${V_{\rm sys}\sim}$5200 km s$^{-1}$). The observations were obtained using…

Astrophysics · Physics 2009-11-07 E. Momjian , J. D. Romney , T. H. Troland

Different physical processes in galaxy evolution, such as galaxy mergers that lead to coalescence of dual Active Galactic Nuclei (AGN) and outflows emanating from the narrow line region, can leave their imprint on the optical spectra of AGN…

Astrophysics of Galaxies · Physics 2022-09-08 Rajeshwari Dutta , Raghunathan Srianand

HI absorption studies yield information on both AGN feeding and feedback processes. This AGN activity interacts with the neutral gas in compact radio sources, which are believed to represent the young or recently re-triggered AGN…

Astrophysics of Galaxies · Physics 2017-02-01 M. Glowacki , J. R. Allison , E. M. Sadler , V. A. Moss , S. J. Curran , A. Musaeva , C. Deng , R. Parry , M. C. Sligo

We present and discuss European VLBI Network UHF band spectral line observations, made to localise the redshifted 21cm HI absorption known to occur in the subgalactic sized compact steep spectrum galaxies 3C 49 and 3C 268.3. We have…

Astrophysics · Physics 2009-11-11 A. Labiano , R. C. Vermeulen , P. D. Barthel , C. P. O'Dea , J. F. Gallimore , S. Baum , W. de Vries

We present 92cm observations of the high-redshift galaxy B2 0902+343 (z=3.40) with the Westerbork Synthesis Radio Telescope (WSRT). Twenty-one cm HI is detected in absorption, at a depth of 15.9 mJy (=~6\sigma) and rest frame velocity width…

Astrophysics · Physics 2009-11-07 Ann Marie Cody , Robert Braun

In this paper we further explore the implications that this has for the currently popular consensus that it is the orientation of the circumnuclear obscuring torus which determines whether absorption is present along our sight-line. The…

Cosmology and Nongalactic Astrophysics · Physics 2010-03-04 S. J. Curran , M. T. Whiting