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Related papers: Giant Radio Galaxies: I. Intergalactic Barometers

200 papers

The warm-hot intergalactic medium (WHIM) at temperatures 1E5-1E7 K is believed to contain 30-50% of the baryons in the local universe. However, all current X-ray detections of the WHIM at redshifts z>0 are of low statistical significance…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Yangsen Yao , J. Michael Shull , Q. Daniel Wang , Webster Cash

We have compiled a sample of 234 ultra-steep-spectrum(USS)-selected radio sources in order to find high-redshift radio galaxies (HzRGs). The sample is in the southern sky at -40 deg < DEC < -30 deg which is the overlap region of the 408-MHz…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 J. J. Bryant , H. M. Johnston , J. W. Broderick , R. W. Hunstead , C. De Breuck , B. M. Gaensler

We have carried out two-dimensional, axisymmetric, hydrodynamic numerical modelling of the evolution of radio galaxy lobes. The emphasis of our work is on including realistic hot-gas environments in the simulations and on establishing what…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 M. J. Hardcastle , M. G. H. Krause

We use the latest multi-redshift ($z=6.5-8.7$) upper limits on the 21-cm signal from the Murchison Widefield Array (MWA) to explore astrophysical models which are inconsistent with the data. These upper limits are achieved using 298 h of…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-25 Bradley Greig , Cathryn M. Trott , Nichole Barry , Simon J. Mutch , Bart Pindor , Rachel L. Webster , J. Stuart B. Wyithe

We present a study of diffuse extragalactic radio emission at $1.75\,$GHz from part of the ELAIS-S1 field using the Australia Telescope Compact Array. The resulting mosaic is $2.46\,$deg$^2$, with a roughly constant noise region of…

Astrophysics of Galaxies · Physics 2015-06-22 T. Vernstrom , Ray P. Norris , Douglas Scott , J. V. Wall

By heating the intergalactic medium (IGM) before reionization, X-rays are expected to play a prominent role in the early Universe. The cosmic 21-cm signal from this "Epoch of Heating" (EoH) could serve as a clean probe of high-energy…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-31 Arpan Das , Andrei Mesinger , Andrea Pallottini , Andrea Ferrara , John H. Wise

Measuring the environments of massive galaxies at high redshift is crucial to understanding galaxy evolution and the conditions that gave rise to the distribution of matter we see in the Universe today. While high-$z$ radio galaxies…

We present a new sample of 84 large angular size radio galaxies selected from the NRAO VLA Sky Survey. Radio sources with declination above +60 degrees, total flux density greater than 100 mJy at 1.4 GHz and angular size larger than 4…

Astrophysics · Physics 2009-11-06 L. Lara , W. D. Cotton , L. Feretti , G. Giovannini , J. M. Marcaide , I. Marquez , T. Venturi

Radio emission at cm wavelengths from highly star-forming galaxies, such as SMGs, is dominated by synchrotron radiation arising from supernova activity. Using deep, high-resolution ($1\sigma=2.3$ $\mu$Jy beam$^{-1}$; $0.75^{"}$) cm…

This paper presents the first results of a far-infrared search for protocluster-associated galaxy overdensities using the SPIRE instrument on-board the {\it Herschel} Space Observatory. Large ($\sim$400 arcmin$^{2}$) fields surrounding 26…

The time evolution of giant lobe-dominated radio galaxies (with projected linear size D>1 Mpc if H_{0}=50 km/s/Mpc and q_{0}=0.5 is analysed on the basis of dynamical evolution of the entire FRII-type population. Two basic physical…

Astrophysics · Physics 2007-05-23 J. Machalski , K. T. Chyzy , M. Jamrozy

We perform a stacking analysis of H-ATLAS data in order to obtain isothermal dust temperatures and rest-frame luminosities at 250um (L250), for 1599 radio sources over the H-ATLAS P1 GAMA area. The radio sample is generated using a…

Cosmological simulations indicate that nearly half of the baryons in the nearby Universe are in the warm-hot intergalactic medium (WHIM) phase, and about a half them reside in cosmic filaments connecting galaxy clusters. Recent…

Astrophysics of Galaxies · Physics 2025-03-14 Yuanyuan Zhao , Haiguang Xu , Ang Liu , Xiaoyuan Zhang , Li Ji , Jiang Chang , Dan Hu , Norbert Werner , Zhongli Zhang , Wei Cui , Xiangping Wu

We present deep near-infrared $K_{\rm s}$-band imaging for 35 of the 53 sources from the high-redshift ($z > 2$) radio galaxy candidate sample defined in Broderick et al. (2022). These images were obtained using the High-Acuity Widefield…

We present Giant Metrewave Radio Telescope 21-cm HI observations towards a sample of compact radio sources behind galaxy groups, to search for cool HI. The results -- from high dynamic range spectra for 8 lines-of-sight through 7 galaxy…

Astrophysics · Physics 2014-10-13 D. A. Green , M. S. Clemens , P. Alexander , H. Cullen , B. Nikolic

This paper introduces a new program to find high-redshift radio galaxies in the southern hemisphere through ultra-steep spectrum (USS) selection. We define a sample of 234 USS radio sources with spectral indices alpha_408^843 < -1.0 and…

Astrophysics · Physics 2009-11-13 J. W. Broderick , J. J. Bryant , R. W. Hunstead , E. M. Sadler , T. Murphy

At low redshifts powerful radio sources are uniquely associated with massive galaxies, and are thought to be powered by supermassive black holes. Modern 8m -- 10m telescopes may be used used to find their likely progenitors at very high…

Astrophysics · Physics 2015-06-24 Wil van Breugel

The redshifts of faint radio galaxies identified with giant radio source candidates selected from the sample of Machalski et al. (2001) have been measured. Given the redshift, the projected linear size and radio luminosity are then…

We present a detailed study of radio-detected dwarf galaxies (with stellar masses less than 3 billion solar masses) to characterize extreme star formation and search for (variable) radio AGNs. Our sample comes from Reines et al. (2020)…

Astrophysics of Galaxies · Physics 2026-05-01 John-Michael Eberhard , Amy E. Reines

The results of analysis of HST I-band imaging of a sample of 41 radio galaxies spanning three orders of magnitude in radio luminosity at redshift z~0.5 are presented. The full sample is drawn from four complete, low-frequency selected radio…