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Related papers: Radio Observations of Cluster Mergers

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Galaxy clusters are the most massive constituents of the large-scale structure of the Universe. While the hot thermal gas that pervades galaxy clusters is relatively well understood through observations with X-ray satellites, our…

High Energy Astrophysical Phenomena · Physics 2017-10-19 F. de Gasperin , H. T. Intema , T. W. Shimwell , G. Brunetti , M. Bruggen , T. A. Ensslin , R. J. van Weeren , A. Bonafede , H. J. A. Rottgering

We performed GMRT low frequency observations of the radio halos, relics and new candidates belonging to the GMRT Radio Halo Cluster Sample first observed at 610 MHz. High sensitivity imaging was performed using the GMRT at 325 MHz and 240…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Tiziana Venturi , Simona Giacintucci , Daniele Dallacasa , Rossella Cassano , Gianfranco Brunetti , Giulia Macario , Ramana Athreya

There is compelling evidence that at least some clusters of galaxies are powerful sources of non-thermal radiation. In all cases where this radiation has been detected, a general trend is that high energy densities of cosmic rays and…

Astrophysics · Physics 2011-05-23 Pasquale Blasi

Radio halos are faint radio sources usually located at the center of merging clusters of galaxies. These diffuse radio sources are rare, having so far been found only in about 30 clusters of galaxies, suggesting that particular conditions…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 M. Murgia , F. Govoni , L. Feretti , G. Giovannini

In this letter we present a morphological comparison between giant radio halos and radio mini-halos in galaxy clusters based on radio--X-ray luminosity, P_{1.4}-L_X, and radio luminosity-size, P_{1.4}-R_H, correlations. We report evidence…

Astrophysics · Physics 2009-11-13 R. Cassano , M. Gitti , G. Brunetti

Our understanding of how AGN feedback operates in galaxy clusters has improved in recent years owing to large efforts in multi-wavelength observations and hydrodynamical simulations. However, it is much less clear how feedback operates in…

Recent observations of the interactions between radio sources and the X-ray-emitting gas in cooling flows in the cores of clusters of galaxies are reviewed. The radio sources inflate bubbles in the X-ray gas, which then rise buoyantly…

Astrophysics · Physics 2007-05-23 Elizabeth L. Blanton

Diffuse radio emission in galaxy clusters is a tracer of ultra-relativistic particles and $\mu$G-level magnetic fields, and is thought to be triggered by cluster merger events. In the distant Universe (i.e. $z>0.6$), such sources have been…

The thermal plasma of galaxy clusters lost most of its information on how structure formation proceeded as a result of dissipative processes. In contrast, non-equilibrium distributions of cosmic rays (CR) preserve the information about…

Astrophysics · Physics 2009-11-13 Christoph Pfrommer , Torsten A. Ensslin , Volker Springel

The intra-cluster medium of several galaxy clusters hosts large-scale regions of diffuse synchrotron radio emission, known as radio halos and relics, which demonstrate the presence of magnetic fields and relativistic electrons in clusters.…

High Energy Astrophysical Phenomena · Physics 2015-10-01 Richard Bartels , Fabio Zandanel , Shin'ichiro Ando

The existence of magnetic fields associated with the intracluster medium in clusters of galaxies is now well established through different methods of analysis. The most detailed evidence for the presence of cluster magnetic fields comes…

Astrophysics · Physics 2009-11-11 Federica Govoni

Galaxy clusters undergo mergers that can generate extended radio sources called radio relics. Radio relics are the consequence of merger-induced shocks that propagate in the intra cluster medium (ICM). In this paper we analyse the radio,…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-21 F. de Gasperin , H. T. Intema , J. Ridl , M. Salvato , R. van Weeren , A. Bonafede , J. Greiner , R. Cassano , M. Bruggen

A diffuse non-thermal component has now been observed in massive merging clusters. To better characterise this component, and to extend analyses done for massive clusters down to a lower mass regime, we are conducting a statistical analysis…

Cosmology and Nongalactic Astrophysics · Physics 2010-06-04 Joseph Lanoux , Etienne Pointecouteau , Martin Giard , Ludovic Montier

We show an interesting correlation between the surface brightness and temperature structure of the relaxed clusters RXJ1720.1+2638 and MS1455.0+2232, hosting a pair of cold fronts, and their central core--halo radio source. We discuss the…

Astrophysics · Physics 2009-11-13 Pasquale Mazzotta , Simona Giacintucci

We present the first deep low frequency radio observations of the massive and highly disturbed galaxy cluster Abell 2744 using the upgraded Giant Metrewave Radio Telescope (uGMRT). The cluster is experiencing a very complex multiple merger…

The most important evidence of non-thermal phenomena in galaxy clusters comes from Giant Radio Halos (GRHs), synchrotron radio sources extended over Mpc scales, detected in a growing number of massive galaxy clusters. A promising…

Astrophysics · Physics 2009-11-11 R. Cassano , G. Brunetti , G. Setti

The idea that mergers are more likely in dense groups or clusters coupled with the assumption that such events lead to cold gas flows onto black holes, suggests a direct relationship between the radiative efficiency of an active galactic…

High Energy Astrophysical Phenomena · Physics 2021-01-06 David Garofalo , Chandra B. Singh

Nonthermal emission observed in galaxy clusters provides a direct probe into the plasma physics of the intra-cluster medium (ICM) under extreme conditions. We report the first detailed analysis of the giant radio halo in the merging galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-01 Ramananda Santra , Ruta Kale , Simona Giacintucci , Herve Bourdin , Rashi Jain , Andrea Botteon , Gianfranco Brunetti

Simulations of structure formation in the Universe predict accretion shock waves at the boundaries of the large-scale structures as sheets, filaments, and clusters of galaxies. If magnetic fields are present at these shocks, particle…

Astrophysics · Physics 2007-05-23 Torsten A. Ensslin , Peter L. Biermann , Ulrich Klein , Sven Kohle

Observations with the RXTE and SAX satellites have recently led to the measurement of a second component in the spectra of several clusters of galaxies which are known to have regions of extended radio emission. This new component is quite…

Astrophysics · Physics 2009-11-06 Yoel Rephaeli
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