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Related papers: Radio activity in major mergings

200 papers

Deep Very Large Array radio observations confirm the presence of halo and relic sources in six clusters of galaxies (A115, A520, A773, A1664, A2254, A2744) where a wide diffuse emission was previously found in the NRAO VLA Sky Survey. New…

Astrophysics · Physics 2009-11-06 F. Govoni , L. Feretti , G. Giovannini , H. Bohringer , T. H. Reiprich , M. Murgia

Radio galaxies are uniquely useful as probes of large-scale structure as their uniform identification with giant elliptical galaxies out to high redshift means that the evolution of their bias factor can be predicted. As the initial stage…

Astrophysics · Physics 2009-10-31 Mark Lacy

Hierarchical models of structure formation predict that galaxy clusters grow via mergers of smaller clusters and galaxy groups, as well as through continuous accretion of gas. MACS J0717.5+3745 is an X-ray luminous and complex merging…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 R. J. van Weeren , H. J. A. Rottgering , M. Bruggen , A. Cohen

Radio relics are sites of electron (re)acceleration in merging galaxy clusters but the mechanism of acceleration and the topology of the magnetic field in and near relics are yet to be understood. We are carrying out an observational…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-08 C. Stuardi , A. Bonafede , D. Wittor , F. Vazza , A. Botteon , N. Locatelli , D. Dallacasa , N. Golovich , M. Hoeft , R. J. van Weeren , M. Brüggen , F. de Gasperin

We present deep near-infrared images, taken with Subaru Telescope, of the region around the z=1.08 radio source 3C 356 which show it to be associated with a poor cluster of galaxies. We discuss evidence that this cluster comprises two…

Astrophysics · Physics 2009-11-07 Chris Simpson , Steve Rawlings

Diffuse, low surface-brightness radio emission in merging galaxy clusters provides insights into cosmic structure formation, the growth of magnetic fields, and turbulence. This paper reports a search for diffuse radio emission in a pilot…

We conduct an intensive study of the rich, X-ray luminous, and hot galaxy cluster Abell 697 (at z=0.282), likely containing a diffuse radio emission, to determine its dynamical status. Our analysis is based on new spectroscopic data…

Astrophysics · Physics 2009-11-11 M. Girardi , W. Boschin , R. Barrena

Galaxies exhibiting a specific large-scale extended radio emission, such as X-shaped radio galaxies, belong to a rare class of winged radio galaxies. The morphological evolution of these radio sources is explained using several theoretical…

Astrophysics of Galaxies · Physics 2023-05-31 Arpita Misra , Marek Jamrozy , Marek Weżgowiec

Using a MeerKAT observation of the galaxy cluster A3562 (a member of the Shapley Supercluster), we have discovered a narrow, long and straight, very faint radio filament, which branches out at a straight angle from the tail of a radio…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-03 S. Giacintucci , T. Venturi , M. Markevitch , H. Bourdin , P. Mazzotta , P. Merluzzi , D. Dallacasa , S. Bardelli , S. P. Sikhosana , O. Smirnov , G. Bernardi

Radio observations were used to detect the `active' galaxy population within rich clusters of galaxies in a non-biased manner that is not plagued by dust extinction or the K-correction. We present wide-field radio, optical (imaging and…

Astrophysics · Physics 2009-11-07 G. E. Morrison , F. N. Owen , M. J. Ledlow , W. C. Keel , J. M. Hill , W. Voges , T. Herter

We present high-angular-resolution radio observations of the Arches cluster in the Galactic centre, one of the most massive young clusters in the Milky Way. The data were acquired in two epochs and at 6 and 10 GHz with the Karl G. Jansky…

The galaxy cluster A3667 was observed using the Two-degree Field (2dF) multifibre spectroscopic system on the Anglo-Australian Telescope in a program designed to examine the velocity structure in the region. Specifically, we sought evidence…

Astrophysics · Physics 2009-11-13 M. Johnston-Hollitt , R. W. Hunstead , E. Corbett

Radio observations of a few cool-core galaxy clusters have revealed the presence of diffuse emission on cluster scales, similar to what was found in merging clusters in the form of radio halos. These sources might suggest that a minor…

We report a discovery of a proto-cluster in vigorous assembly and hosting strong star forming activities, associated to a radio galaxy USS 1558-003 at z=2.53, as traced by a wide-field narrow-band H_alpha imaging with MOIRCS on Subaru…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Masao Hayashi , Tadayuki Kodama , Ken-ichi Tadaki , Yusei Koyama , Ichi Tanaka

We present evidence for the existence of shock waves caused by the formation of the large-scale structure. In some clusters of galaxies peripherally located sources of extended diffuse radio emission exist, the so-called cluster radio…

Astrophysics · Physics 2011-05-23 Torsten A. Ensslin , Peter L. Biermann , Ulrich Klein , Sven Kohle

We present results on the stellar populations of 232 quiescent galaxies in the Shapley Supercluster, based on spectroscopy from the AAOmega spectrograph at the AAT. The key characteristic of this survey is its coverage of many…

Astrophysics · Physics 2009-11-13 Russell J. Smith , John R. Lucey , Michael J. Hudson

We use deep Herschel Space Observatory observations of a 90% complete sample of 32 intermediate-redshift 2Jy radio galaxies (0.05 < z < 0.7) to estimate the dust masses of their host galaxies and thereby investigate the triggering…

Astrophysics of Galaxies · Physics 2015-06-22 C. Tadhunter , D. Dicken , R. Morganti , V. Konyves , N. Ysard , N. Nesvadba , C. Ramos Almeida

We present new optical spectroscopy for 342 R<18 galaxies in the Shapley Supercluster obtained with the AAOmega facility at the Anglo-Australian Telescope. We describe the observations and measurements of central velocity dispersion,…

Astrophysics · Physics 2009-11-13 Russell J. Smith , John R. Lucey , Michael J. Hudson

Radio halos are diffuse synchrotron sources on scales of ~1 Mpc that are found in merging clusters of galaxies, and are believed to be powered by electrons re-accelerated by the merger-driven turbulence. We present measurements of extended…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-18 Martin W. Sommer , Kaustuv Basu , Huib Intema , Florian Pacaud , Annalisa Bonafede , Arif Babul , Frank Bertoldi

Radio-loud AGN play an important r\^ole in galaxy evolution. We need to understand their properties, and the processes that affect their behaviour in order to model galaxy formation and development. We here present preliminary results of an…

Astrophysics of Galaxies · Physics 2015-06-23 Judith Ineson , Judith Croston , Martin Hardcastle , Ralph Kraft , Daniel Evans , Matt Jarvis