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Related papers: HI Absorption in High-Frequency Peaker Galaxies

200 papers

Large-scale radio continuum surveys provide data to get insights into the physical properties of radio sources. HII regions are prominent radio sources produced by thermal emission of ionised gas around young massive stars. We identify and…

Astrophysics of Galaxies · Physics 2019-03-13 X. Y. Gao , P. Reich , L. G. Hou , W. Reich , J. L. Han

High-redshift radio galaxies (HzRGs) are among the most massive galaxies in the Universe and sites of extreme active galactic nuclei (AGN) feedback processes, powering energetic radio jets. They are typically embedded in giant Ly$\alpha$…

Astrophysics of Galaxies · Physics 2026-04-30 Jelena Ritter , Wuji Wang , Dominika Wylezalek , Carlos De Breuck , Joël Vernet , Fabrizio Arrigoni Battaia

We present a new Hubble Space Telescope (HST) Cosmic Origins Spectrograph (COS) absorption-line survey to study halo gas around 16 luminous red galaxies (LRGs) at z=0.21-0.55. The LRGs are selected uniformly with stellar mass Mstar>1e11…

We detect the neutral hydrogen (HI) radial brightness temperature profile in large-scale haloes by stacking 48,430 galaxies selected from the 2dFGRS catalogue onto a set of 21-cm intensity maps obtained with the Parkes radio telescope,…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-14 Denis Tramonte , Yin-Zhe Ma

GPS and CSS sources are thought to represent a young and/or confined sub-population of radio-loud active galactic nuclei (AGN) that are yet to evacuate their surrounding ambient interstellar gas. By studying the gaseous environments of…

Astrophysics of Galaxies · Physics 2022-01-05 James R. Allison , Elaine M. Sadler , Elizabeth K. Mahony , Vanessa A. Moss , Hyein Yoon

We present Giant Metrewave Radio Telescope (GMRT) observations of redshifted 21-cm absorption from the $z=0.437$ metal line absorption system towards PKS 1243-072. HI absorption is clearly detected; the absorption profile has a velocity…

Astrophysics · Physics 2009-11-07 Nissim Kanekar , Ramana M. Athreya , Jayaram N. Chengalur

We present 7mm Very Large Array continuum images of the starburst galaxy M82. On arcsecond scales, two-thirds of the 7mm continuum consists of free-free emission from HII regions. In the subarcsecond resolution map, we identify 14 compact…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 Chao-Wei Tsai , Jean L. Turner , Sara C. Beck , David S. Meier , Paul T. P. Ho

Aims: The ``bright'' High Frequency Peakers (HFPs) sample is a mixture of blazars and intrinsically small and young radio sources. We investigate the polarimetric characteristics of 45 High Frequency Peakers, from the ``bright'' HFP sample,…

Astrophysics · Physics 2009-11-13 M. Orienti , D. Dallacasa

The Ultra Luminous InfraRed Galaxy Mrk 231 reveals up to seven rotational lines of water (H2O) in emission, including a very high-lying (E_{upper}=640 K) line detected at a 4sigma level, within the Herschel/SPIRE wavelength range, whereas…

We report on the detection of a population of weak metal-line absorbers in the halo or nearby intergalactic environment of the Milky Way. Using high-resolution ultraviolet absorption-line spectra of bright QSOs obtained with the Space…

Astrophysics of Galaxies · Physics 2014-11-18 Philipp Richter , Jane C. Charlton , Alessio P. M. Fangano , Nadya Ben Bekhti , Joseph R. Masiero

We present recent results from our searches of 21-cm absorption using GBT, GMRT, VLBA and WSRT to trace the evolution of cold gas in galaxies. Using ~130 sight lines with 21-cm absorption measurements, we find that within the measurement…

Astrophysics of Galaxies · Physics 2014-02-24 N. Gupta , R. Srianand , P. Petitjean , P. Noterdaeme , E. Momjian

We present results from a sample of 106 high-luminosity IRAS sources observed with the Very Large Array in the B and C configurations. 96 sources were observed in the X-band and 52 in the K-band, with 42 of them observed at both…

Astrophysics of Galaxies · Physics 2023-06-16 D. Quiroga-Gonzalez , M. A. Trinidad , E. de la Fuente , J. M. Masque , T. Rodriguez-Esnard

At low radio frequencies (< 100 MHz), classical HII regions may become optically thick (optical depth > 1) and can be observed as discrete absorption regions against the Galactic nonthermal background emission created by Galactic cosmic ray…

Astrophysics · Physics 2008-11-26 Michael E. Nord , P. A. Henning , R. J. Rand , T. Joseph W. Lazio , Namir E. Kassim

Ultra-steep spectrum (USS) radio sources are good tracers of powerful radio galaxies at $z > 2$. Identification of even a single bright radio galaxy at $z > 6$ can be used to detect redshifted 21cm absorption due to neutral hydrogen in the…

Astrophysics of Galaxies · Physics 2018-01-31 A. Saxena , P. Jagannathan , H. J. A. Röttgering , P. N. Best , H. T. Intema , M. Zhang , K. J. Duncan , C. L. Carilli , G. K. Miley

We use a large N-body simulation to examine the detectability of HI in emission at redshift z ~ 1, and the constraints imposed by current observations on the neutral hydrogen mass function of galaxies at this epoch. We consider three…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Nishikanta Khandai , Shiv K. Sethi , Tiziana Di Matteo , Rupert A. C. Croft , Volker Springel , Anirban Jana , Jeffrey P. Gardner

We report on the discovery of HI in absorption toward the gigamaser galaxy TXS2226-184 using the VLA. The absorption appears to consist of two components -- one with a width of 125 km/s, and one broader (420 km/s), both toward the compact…

The empirical studies of cold gas content serve as an essential aspect in comprehending the star formation activities and evolution in galaxies. However, it is not straightforward to understand these processes because they depend on various…

We study the atomic neutral hydrogen (HI) content of $\sim$1600 galaxies up to $z \sim 0.1$ using stacking techniques. The observations were carried out with the Westerbork Synthesis Radio Telescope (WSRT) in the area of the SDSS South…

Astrophysics of Galaxies · Physics 2015-08-06 K. Gereb , R. Morganti , T. Oosterloo , L. Hoppmann , L. Staveley-Smith