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Related papers: The beautiful mess in Abell 2255

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Large-scale magnetic fields reveal themselves through diffuse synchrotron sources observed in galaxy clusters such as radio halos. Total intensity filaments of these sources have been observed in polarization as well, but only in three…

We present the first multi-frequency analysis of the candidate ultra-steep spectrum radio halo in the galaxy cluster PLCKESZ G171.94$-$40.65, using the upgraded Giant Metrewave Radio telescope (uGMRT; 400 MHz), and Karl G. Jansky Very Large…

We report on new VLA radio observations of the distant cluster RX J1347.5-1145, which is the most luminous in X-rays. We aim at investigating the possible presence of diffuse and extended radio emission in this very peculiar system which…

Deep radio observations of galaxy clusters have revealed the existence of diffuse radio sources related to the presence of relativistic electrons and weak magnetic fields in the intracluster volume. The role played by this non-thermal…

We present results from an observation of the luminous cluster of galaxies Abell 2204 using the Chandra X-ray Observatory. We show the core of the cluster has a complex morphological structure, made up of a high density core (n_e~0.2 cm^-3)…

Astrophysics · Physics 2009-09-17 J. S. Sanders , A. C. Fabian , G. B. Taylor

Diffuse radio sources in galaxy clusters are unique signposts of cluster assembly in the Universe. Our knowledge of their observational properties has considerably improved over the past decade, and the long standing questions concerning…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-18 Tiziana Venturi , INAF , Istituto di Radioastronomia

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 study the structure of the galaxy cluster Abell 523 (A523) at z=0.104 using new spectroscopic data for 132 galaxies acquired at the Telescopio Nazionale Galileo, new photometric data from the Isaac Newton Telescope, and X-ray and radio…

Astrophysics of Galaxies · Physics 2016-01-27 M. Girardi , W. Boschin , F. Gastaldello , G. Giovannini , F. Govoni , M. Murgia , R. Barrena , S. Ettori , M. Trasatti , V. Vacca

We present multi-frequency, multi-epoch radio imaging of the complex radio source B2151+174 in the core of the cluster, Abell 2390 (z~0.23). From new and literature data we conclude that the FRII-powerful radio source is the combination of…

Astrophysics · Physics 2016-08-30 Pedro Augusto , Alastair C. Edge , Claire J. Chandler

The goal of this work is to constrain the strength and structure of the magnetic field in the nearby cluster of galaxies A2255. At radio wavelengths A2255 is characterized by the presence of a polarized radio halo at the cluster center, a…

Astrophysics · Physics 2009-11-11 F. Govoni , M. Murgia , L. Feretti , G. Giovannini , K. Dolag , G. B. Taylor

A781 belongs to a complex system characterized by extended X-ray emissions that may form part of line of clusters of galaxies along a filament. The aim of this work is to investigate the possible presence of extended, diffuse synchrotron…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 F. Govoni , M. Murgia , G. Giovannini , V. Vacca , A. Bonafede

Extended, steep, and ultra-steep spectrum radio emission in a galaxy cluster is usually associated with recent mergers. Simulations show that radio phoenixes are aged radio galaxy lobes whose emission reactivates when a low Mach shock…

High Energy Astrophysical Phenomena · Physics 2022-07-20 Majidul Rahaman , Ramij Raja , Abhirup Datta , Jack O Burns , David Rapetti

We present LOFAR $120-168$ MHz images of the merging galaxy cluster Abell 1240 that hosts double radio relics. In combination with the GMRT $595-629$ MHz and VLA $2-4$ GHz data, we characterised the spectral and polarimetric properties of…

We present results from an X-ray and radio study of the merging galaxy cluster Abell 115. We use the full set of 5 Chandra observations taken of A115 to date (360 ks total integration) to construct high-fidelity temperature and surface…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-06 Eric J. Hallman , Brian Alden , David Rapetti , Abhirup Datta , Jack O. Burns

The origin of radio relics is usually explained via diffusive shock acceleration (DSA) or re-acceleration of electrons at/from merger shocks in galaxy clusters. The case of acceleration is challenged by the low predicted efficiency of…

A fraction of galaxy clusters host diffuse radio sources whose origins are investigated through multi-wavelength studies of cluster samples. We investigate the presence of diffuse radio emission in a sample of seven galaxy clusters in the…

In this paper we present a detailed study of the giant radio halo in the galaxy cluster Abell 697, with the aim to constrain its origin and connection with the cluster dynamics. We performed high sensitivity GMRT observations at 325 MHz,…

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

Mega-parsec scale radio sources in the form of halos and relics are often detected in dynamically disturbed galaxy clusters. Although they are associated with merger-induced turbulence and shocks, respectively, their formation is not fully…

We present the results of deep Chandra and XMM-Newton observations of a complex merging galaxy cluster Abell 2256 (A2256) that hosts a spectacular radio relic (RR). The temperature and metallicity maps show clear evidence of a merger…