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Related papers: The cluster relic source in A521

200 papers

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

Radio relics, arc-like polarized sources with highly aligned magnetic fields, are typically found on the outskirts of merging galaxy clusters. The magneto-ionic media responsible for the significant coherence observed in radio relics remain…

High Energy Astrophysical Phenomena · Physics 2025-08-28 Arpan Pal , Ruta Kale , Reinout J. van Weeren

We report polarimetry results of a merging cluster of galaxies Abell 2256 with Karl G. Jansky Very Large Array (JVLA). We performed new observations with JVLA at S-band (2051-3947 MHz) and X-band (8051-9947 MHz) in the C array…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-07 Takeaki Ozawa , Hiroyuki Nakanishi , Takuya Akahori , Kenta Anraku , Motokazu Takizawa , Ikumi Takahashi , Sachiko Onodera , Yuya Tsuda , Yoshiaki Sofue

We study diffuse radio emission in the galaxy cluster A1550, with the aim of constraining particle re-acceleration in the intra-cluster medium. We exploit observations at four different frequencies: 54, 144, 400 and 1400 MHz. To complement…

Radio halos are elusive sources located at the center of merging galaxy clusters. To date, only about 40 radio halos are known, thus the discovery of new halos provide important insights on this class of sources. To improve the statistics…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 F. Govoni , C. Ferrari , L. Feretti , V. Vacca , M. Murgia , G. Giovannini , R. Perley , C. Benoist

We report on new 1.41 GHz Green Bank Telescope and 352 MHz Westerbork Synthesis Radio Telescope observations of the Coma cluster and its environs. At 1.41 GHz we tentatively detect an extension to the Coma cluster radio relic source…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Shea Brown , Lawrence Rudnick

Aims. We present the first results of an ongoing project devoted to the search of giant radio halos in galaxy clusters located in the redshift range z=0.2--0.4. One of the main goals of our study is to measure the fraction of massive galaxy…

Astrophysics · Physics 2009-11-11 T. Venturi , S. Giacintucci , G. Brunetti , R. Cassano , S. Bardelli , D. Dallacasa , G. Setti

We report extensive VLA and ATCA observations of the two diffuse radio sources in the cluster of galaxies Abell 548b, which confirm their classification as relics. The two relics (named A and B) show similar flux density, extent, shape,…

Astrophysics · Physics 2009-11-11 L. Feretti , M. Bacchi , O. B. Slee , G. Giovannini , F. Govoni , H. Andernach , G. Tsarevsky

The remnant radio galaxies in galaxy clusters are important sources of seed relativistic electron population in the intra-cluster medium (ICM). Their occurrence and spectral properties are poorly studied. In this work we present a broadband…

Astrophysics of Galaxies · Physics 2018-08-22 Ruta Kale , Viral Parekh , K. S. Dwarakanath

We present deep VLA observations of the merging galaxy cluster Abell 2256. This cluster is known to possess diffuse steep spectrum radio relic emission in the peripheral regions. Our new observations provide the first detailed image of the…

Astrophysics · Physics 2008-11-26 Tracy E. Clarke , Torsten A. Ensslin

We report the discovery of a unique radio galaxy at z=0.137, which could possibly be the second spiral-host large radio galaxy and also the second triple-double episodic radio galaxy. The host galaxy shows signs of recent star formation in…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Ananda Hota , S. K. Sirothia , Youichi Ohyama , C. Konar , Suk Kim , Soo-Chang Rey , D. J. Saikia , J. H. Croston , Satoki Matsushita

The ASKAP-EMU survey is a deep wide-field radio continuum survey designed to cover the entire southern sky and a significant fraction of the northern sky up to $+30^{\circ}$. Here, we report a discovery of a radio relic in the merging…

We present a multi-wavelength analysis of the merging rich cluster of galaxies Abell 2256. We have observed A2256 at 150 MHz using the Giant Metrewave Radio Telescope and successfully detected the diffuse radio halo and the relic emission…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Kale Ruta , K. S. Dwarakanath

We present new arcminute resolution radio images of the low surface brightness radio source PKS B1400-33 that is located in the poor cluster Abell S753. The observations consist of 330 MHz VLA, 843 MHz MOST and 1398 and 2378 MHz ATCA data.…

Astrophysics · Physics 2009-11-07 R. Subrahmanyan , A. J. Beasley , W. M. Goss , K. Golap , R. W. Hunstead

Radio relics are diffuse, extended synchrotron sources that originate from shock fronts generated during cluster mergers. The massive merging galaxy cluster MACS J0717.5+3745 hosts one of the more complex relics known to date. We present…

We report the discovery of a putative radio relic, 830 kpc in length and found toward the outskirts of galaxy cluster Abell 1697 ($z=0.181$), using the LOFAR Two Meter Sky Survey (LoTSS) at 144 MHz. With an X-ray-inferred mass of…

Astrophysics of Galaxies · Physics 2020-01-15 Surajit Paul , Sameer Salunkhe , Satish Sonkamble , Prateek Gupta , Tony Mroczkowski , Somak Raychaudhury

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 the results of observations performed with the Sardinia Radio Telescope (SRT) at 1.3-1.8 GHz of the galaxy cluster CL 0217+70 and a $3^\circ \times 3^\circ$ region around it. We combine the SRT data with archival Very Large Array…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-13 P. Marchegiani , V. Vacca , F. Govoni , M. Murgia , F. Loi , L. Feretti

An extremely deep 5 GHz radio observation is presented of the rich cluster MS1054-03 at redshift z=0.83. 34 radio sources are detected down to a 32 micro-Jy (6 sigma), compared to about 25 expected from previous blank field radio source…

Astrophysics · Physics 2009-11-07 P. N. Best , P. G. van Dokkum , M. Franx , H. J. A. Rottgering

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…