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相关论文: Parsec-scale HI absorption structure in a low-reds…

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We present observations of HI and OVI absorption systems proximate to a galaxy at z_gal = 0.3529. The absorption was detected serendipitously in Cosmic Origins Spectrograph observations of the low-z QSO J0943+0531 (z_qso = 0.564). The data…

宇宙学与河外天体物理 · 物理学 2015-05-28 C. Thom , J. K. Werk , J. Tumlinson , J. X. Prochaska , J. D. Meiring , T. M. Tripp , K. R. Sembach

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…

宇宙学与河外天体物理 · 物理学 2015-06-11 J. R. Allison , E. M. Sadler , S. J. Curran , S. N. Reeves

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…

宇宙学与河外天体物理 · 物理学 2015-05-30 Yogesh Chandola , S. K. Sirothia , D. J. Saikia

We present sensitive, high-resolution 21-cm VLBA+VLA observations of the radio jet and nuclear HI absorption in NGC 4151. The 25-mas (1.6-pc) resolution continuum image reveals a highly collimated radio jet, underlying the discrete…

天体物理学 · 物理学 2007-05-23 C. G. Mundell , J. M. Wrobel , A. Pedlar , J. F. Gallimore

We present the results of a pilot survey for neutral hydrogen (HI) 21 cm absorption in the Arecibo Legacy Fast Arecibo L-Band Feed Array (ALFALFA) Survey. This project is a wide-area "blind" search for HI absorption in the local universe,…

宇宙学与河外天体物理 · 物理学 2015-05-30 Jeremy Darling , Erin P. Macdonald , Martha P. Haynes , Riccardo Giovanelli

Using a combination of observations involving the VLA, MERLIN and global VLBI networks we have made a detailed study of the radio continuum and the neutral hydrogen (HI) kinematics and distribution within the central kiloparsec of the radio…

天体物理学 · 物理学 2009-11-10 R. J. Beswick , A. B. Peck , G. B. Taylor , G. Giovannini

We present 21-cm HI line and 13-cm continuum observations, obtained with the Australian Long Baseline Array, of the Seyfert 2 galaxy IC 5063. This object appears to be one of the best examples of Seyfert galaxies where shocks produced by…

天体物理学 · 物理学 2009-10-31 T. A. Oosterloo , R. Morganti , A. Tzioumis , J. Reynolds , E. King , P. McCulloch , Z. Tsvetanov

We present a pilot study of extragalactic HI 21-cm absorption lines using the Five-hundred-meter Aperture Spherical radio Telescope (FAST). We observed 5 continuum sources with HI absorption features firstly identified in the 40% data…

星系天体物理 · 物理学 2021-03-31 Bo Zhang , Ming Zhu , Zhong-Zu Wu , Qing-Zheng Yu , Peng Jiang , You-Ling Yue , Meng-Lin Huang , Qiao-Li Hao

We present new high-spectral-resolution MeerKAT observations of $\mathrm{HI}$ absorption against the central region of the restarted, giant, X-shaped radio galaxy PKS2014-55, which exhibits morphological evidence of three distinct cycles of…

We present a detailed study of the quasar-galaxy pair: J1243+4043 - UGC07904. The sight line of the background quasar ( $z_q$= 1.5266) passes through a region of the galaxy ($z_g$=0.0169) at an impact parameter of 6.9 kpc with high…

星系天体物理 · 物理学 2018-02-28 N. Gupta , R. Srianand , J. S. Farnes , Y. Pidopryhora , M. Vivek , Z. Paragi , P. Noterdaeme , T. Oosterloo , P. Petitjean

We present Giant Metrewave Radio Telescope (GMRT) HI 21cm emission images of the z=0.009 damped Lyman-alpha (DLA) absorber towards the QSO HS 1543+5921. The DLA has been earlier identified as a low surface brightness galaxy SBS 1543+593 at…

天体物理学 · 物理学 2009-11-07 Jayaram N. Chengalur , Nissim Kanekar

(Abridged) We present an imaging and spectroscopic survey of galaxies in fields around QSOs HE0226-4110, PKS0405-123, and PG1216+069. The fields are selected to have ultraviolet echelle spectra available, which uncover 195 Lya absorbers and…

宇宙学与河外天体物理 · 物理学 2011-02-11 Hsiao-Wen Chen , John S. Mulchaey

We present three epochs of VLBA observations of Galactic HI absorption toward the quasar 3C~138 with resolutions of 20 mas (~ 10 AU). This analysis includes VLBA data from observations in 1999 and 2002 along with a reexamination of 1995…

天体物理学 · 物理学 2008-11-26 C. L. Brogan , B. A. Zauderer , T. J. Lazio , W. M. Goss , C. D. De Pree , M. D. Fasion

We present the results of a z>2.9 survey for HI 21-cm and molecular absorption in the hosts of radio quasars using the GMRT and the Tidbinbilla 70-m telescope. Previously published searches, which are overwhelmingly at redshifts of z<1,…

天体物理学 · 物理学 2015-05-13 S. J. Curran , M. T. Whiting , T. Wiklind , J. K. Webb , M. T. Murphy , C. R. Purcell

We present results from two projects in which we have used the HI 21cm emission line as a tracer of gas-rich galaxy populations in the vicinity of Lyman-alpha absorbers. In the first case, we examine the HI environment of SBS 1543+593, the…

天体物理学 · 物理学 2009-11-11 J. L. Rosenberg

We report the discovery of a further line of sight allowing detection of HeII Ly alpha absorption by the intergalactic medium. A HST/STIS survey of 32 bright z ~ 3 quasars selected from the Hamburg Quasar Surveys yielded one detection…

天体物理学 · 物理学 2016-08-30 D. Reimers , C. Fechner , H. -J. Hagen , P. Jakobsen , D. Tytler , D. Kirkman

In hierarchical cosmogonies at redshift three the matter content of a typical present-day galaxy is dispersed over several individual clumps embedded in sheet-like structures, often aligned along filaments. We have used hydrodynamical…

天体物理学 · 物理学 2016-08-30 Michael Rauch , Martin G. Haehnelt , Matthias Steinmetz

We have searched for HI 21cm absorption toward the two brightest radio AGN at high redshift, J0924--2201 at $z = 5.20$, and J0913+5919 at $z=5.11$, using the Giant Meter Wave Radio Telescope (GMRT). These data set a 3$\sigma$ upper limit to…

天体物理学 · 物理学 2008-11-26 C. L. Carilli , Ran Wang , M. van Hoven , K. Dwarakanath , J. Chengalur , S. Wyithe

In an effort to study Damped Lyman Alpha galaxies at low redshift, we have been using the Sloan Digital Sky Survey to identify galaxies projected onto QSO sightlines and to characterize their optical properties. For low redshift galaxies,…

宇宙学与河外天体物理 · 物理学 2015-05-14 Brian Cherinka , Regina Schulte-Ladbeck , Jessica Rosenberg

We present results from MUSE observations of a 21-cm HI absorption system detected with the Australian Square Kilometre Array Pathfinder radio telescope at redshift $z = 0.4503$ towards the $z = 1.71$ quasar PKS 1610-771. We identify four…