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Related papers: Spectral Index Studies of the Diffuse Radio Emissi…

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Abell 1351 is a massive merging cluster that hosts a giant radio halo and a bright radio edge blended in the halo. In this paper, we present the first ever spectral analysis of this cluster using GMRT 610 MHz and VLA 1.4 GHz archival data…

High Energy Astrophysical Phenomena · Physics 2022-08-17 Swarna Chatterjee , Majidul Rahaman , Abhirup Datta , Ramij Raja

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

We present the first detailed analysis of the ultra-steep spectrum radio halo in the merging galaxy cluster Abell 521, based on upgraded Giant Metrewave Radio telescope (uGMRT) observations. The combination of radio observations (300-850…

New radio data at 330 MHz are presented for the rich clusters Abell 665 and Abell 2163, whose radio emission is characterized by the presence of a radio halo. These images allowed us to derive the spectral properties of the two clusters…

Astrophysics · Physics 2009-11-10 L. Feretti , E. Orru' , G. Brunetti , G. Giovannini , N. Kassim , G. Setti

Mergers between galaxy clusters often drive shocks into the intra cluster medium (ICM), the effects of which are sometimes visible via temperature and density jumps in the X-ray, and via radio emission from relativistic particles energized…

We present VLA radio and Chandra X-ray observations of the merging galaxy cluster Abell 3411. For the cluster, we find an overall temperature of 6.4 keV and an X-ray luminosity of 2.8 x 10^{44} erg s^{-1} between 0.5 and 2.0 keV. The…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-23 R. J. van Weeren , K. Fogarty , C. Jones , W. R. Forman , T. E. Clarke , M. Bruggen , R. P. Kraft , D. V. Lal , S. S. Murray , H. J. A. Rottgering

Deep radio observations of the galaxy cluster Abell 781 have been carried out using the Giant Metrewave Radio Telescope at 325 MHz and have been compared to previous 610 MHz observations and to archival VLA 1.4 GHz data. The radio emission…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 T. Venturi , S. Giacintucci , D. Dallacasa , G. Brunetti , R. Cassano , G. Macario , R. Athreya

We present results from a spatially resolved spectral analysis of the merging cluster Abell 2256. The long integration time (135 ks) and the good spatial resolution of the MECS onboard BeppoSAX allow us to derive a new and substantially…

Astrophysics · Physics 2009-10-31 Silvano Molendi , Sabrina De Grandi , Roberto Fusco-Femiano

Abell 3266 is a massive and complex merging galaxy cluster that exhibits significant substructure. We present new, highly sensitive radio continuum observations of Abell 3266 performed with the Australian Square Kilometre Array Pathfinder…

We present a new 400ks Chandra X-ray observation and a GMRT radio observation at 325MHz of the merging galaxy cluster Abell 2146. The Chandra observation reveals detailed structure associated with the major merger event including the Mach…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 H. R. Russell , R. J. van Weeren , A. C. Edge , B. R. McNamara , J. S. Sanders , A. C. Fabian , S. A. Baum , R. E. A. Canning , M. Donahue , C. P. O'Dea

We aim to obtain a consistent description of non-thermal emissions from Abell 2256 and to give a prediction for a gamma-ray emission from this galaxy cluster. Assuming that a radio relic illuminates a localization of an ongoing merger, and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 G. Siemieniec-Ozieblo , B. M. Pasternak

We present new low-frequency ($\nu = 88$-216 MHz) observations of the complex merging galaxy cluster Abell 3266. These new observations are taken with the Murchison Widefield Array (MWA) in its Phase II 'extended', long-baseline…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-16 S. W. Duchesne , M. Johnston-Hollitt , C. J. Riseley , I. Bartalucci , S. R. Keel

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…

Diffuse radio emission has been found in many galaxy clusters, predominantly in massive systems which are in the state of merging. The radio emission can usually be classified as relic or halo emission, which are believed to be related to…

A number of radio observations have revealed the presence of large synchrotron-emitting sources associated with the intra-cluster medium. There is strong observational evidence that the emitting particles have been (re-)accelerated by…

We present results on 12 X-ray bright clusters observed at 1.4 GHz with the Green Bank Telescope. After subtraction of point sources, we reach a median (best) 1-sigma noise level of 0.01 (0.006) microJy/sq. arcsec, and find a significant…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Damon Farnsworth , Lawrence Rudnick , Shea Brown , Gianfranco Brunetti

New radio and X-ray data are reported for the rich cluster Abell 2255. The cluster radio emission is characterized by the presence of a diffuse halo source, located at the cluster center, and a more peripheral ridge of radio emission which…

Astrophysics · Physics 2007-05-23 L. Feretti , H. Boehringer , G. Giovannini , D. Neumann

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

The mechanisms giving rise to diffuse radio emission in galaxy clusters, and in particular their connection with cluster mergers, are still debated. We aim to obtain new insights into the internal dynamics of the cluster Abell 2294,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 M. Girardi , W. Boschin , R. Barrena

The galaxy cluster Abell 523 (A523) hosts an extended diffuse synchrotron source historically classified as a radio halo. Its radio power at 1.4 GHz makes it one of the most significant outliers in the scaling relations between observables…