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Related papers: GMRT observations of the Ophiuchus galaxy cluster

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We present high resolution 240 and 607 MHz GMRT radio observations, complemented with 74 MHz archival VLA radio observations of the Ophiuchus cluster of galaxies, whose radio mini-halo has been recently detected at 1400 MHz. We also present…

A fraction of galaxy clusters host diffuse radio sources called radio halos, radio relics and mini-halos. We present the sample and first results from the Extended GMRT Radio Halo Survey (EGRHS)- an extension of the GMRT Radio Halo Survey…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 R. Kale , T. Venturi , S. Giacintucci , D. Dallacasa , R. Cassano , G. Brunetti , G. Macario , R. Athreya

We report the discovery of extended radio emission in the Phoenix cluster (SPT-CL J2344-4243, z=0.596) with the GMRT at 610 MHz. The diffuse emission extends over a region of at least 400-500 kpc and surrounds the central radio source of…

We recently performed a study of a sample of relaxed, cooling core galaxy clusters with deep Very Large Array observations at 1.4 GHz. We find that in the central regions of A1835, A2029, and Ophiuchus the dominant radio galaxy is…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 M. Murgia , F. Govoni , M. Markevitch , L. Feretti , G. Giovannini , G. B. Taylor , E. Carretti

We present high-sensitivity follow-up observations of the giant fossil radio lobe in the Ophiuchus galaxy cluster with the upgraded Giant Metrewave Radio Telescope (uGMRT) in the 125-250 MHz and 300-500 MHz frequency bands. The new data…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-29 Simona Giacintucci , Maxim Markevitch , Tracy Clarke , Daniel R. Wik

High sensitivity observations of radio halos in galaxy clusters at frequencies lower than 330 MHz are still relatively rare, and very little is known compared to the classical 1.4 GHz images. The few radio halos imaged down to 150-240 MHz…

Cosmology and Nongalactic Astrophysics · Physics 2011-07-13 T. Venturi , S. Giacintucci , D. Dallacasa

The GMRT Radio Halo Survey, carried out at 610 MHz to investigate the statistical properties of cluster radio halos in a complete cluster sample selected in the redshift interval z=0.2-0.4, has significantly improved our understanding of…

Cosmology and Nongalactic Astrophysics · Physics 2009-03-18 T. Venturi , S. Giacintucci , R. Cassano , G. Brunetti , D. Dallacasa , G. Macario , G. Setti , S. Bardelli , R. Athreya

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

The knowledge of the origin and statistical properties of diffuse radio emission in galaxy clusters has appreciably improved thanks to the GMRT Radio Halo Survey, a project based on 610 MHz observations of clusters belonging to a…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-10 Simona Giacintucci

Observations with modern radio interferometers are uncovering the intricate morphology of synchrotron sources in galaxy clusters, both those arising from the intracluster medium (ICM) and those associated with member galaxies. Moreover, in…

Astrophysics of Galaxies · Physics 2025-04-24 Andrea Botteon , Marco Balboni , Iacopo Bartalucci , Fabio Gastaldello , Reinout J. van Weeren

Diffuse radio sources, known as mini-halos and halos, are detected at the centres of galaxy clusters. These centralized diffuse sources are typically observed individually, with both appearing together only in rare cases. The origin of the…

High Energy Astrophysical Phenomena · Physics 2025-03-26 D. N. Hoang , M. Brüggen , A. Bonafede , P. M. Koch , G. Brunetti , E. Bulbul , G. Di Gennaro , A. Liu , C. J. Riseley , H. J. A. Röttgering , R. J. van Weeren

Spectral index images can be used to constraint the energy spectrum of relativistic electrons and magnetic field distribution in radio halos and relics, providing useful information to understand their formation, evolution and connection to…

Astrophysics · Physics 2009-11-13 E. Orru' , M. Murgia , L. Feretti , F. Govoni , G. Brunetti , G. Giovannini , M. Girardi , G. Setti , .

The intra-cluster medium contains cosmic rays and magnetic fields that are manifested through the large scale synchrotron sources, termed as radio halos, relics and mini-halos. The Extended Giant Metrewave Radio Telescope (GMRT) Radio Halo…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-08 R. Kale , T. Venturi , S. Giacintucci , D. Dallacasa , R. Cassano , G. Brunetti , V. Cuciti , G. Macario , R. Athreya

Some galaxy clusters show diffuse radio emission in the form of giant halos (GHs) on Mpc scales or minihalos (MHs) on smaller scales. Comparing VLA and XMM radial profiles of several such clusters, we find a universal linear correlation…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Uri Keshet , Abraham Loeb

Diffuse radio emission from galaxy clusters in the form of radio halos and relics are tracers of the shocks and turbulence in the intra-cluster medium. The imprints of the physical processes that govern their origin and evolution can be…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-08 Ruta Kale

Studies have shown that mergers of massive galaxy clusters produce shocks and turbulence in the intra-cluster medium, the possible event that creates radio relics, as well as the radio halos. Here we present GMRT dual-band (235 and 610~MHz)…

High Energy Astrophysical Phenomena · Physics 2019-09-17 Surajit Paul , Sameer Salunkhe , Abhirup Datta , Huib T. Intema

We present the results of the GMRT cluster radio halo survey. The main purposes of our observational project are to measure which fraction of massive galaxy clusters in the redshift range z=0.2--0.4 hosts a radio halo, and to constrain the…

Astrophysics · Physics 2009-11-13 T. Venturi , S. Giacintucci , D. Dallacasa , R. Cassano , G. Brunetti , S. Bardelli , G. Setti

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

The Perseus cluster is a nearby cool-core galaxy cluster that hosts an archetypal radio mini-halo. Recent Low Frequency Array (LOFAR) High Band Antenna (HBA) observations at 120 - 168 MHz have revealed the presence of a giant radio halo…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-26 C. Groeneveld , R. J. van Weeren , M. -L. Gendron-Marsolais , E. Osinga , A. Botteon , F. de Gasperin , M. Cianfaglione , G. di Gennaro , G. Brunetti , R. Cassano

The electron population inferred to be responsible for the mini-halo within the Ophiuchus galaxy cluster is a steep power-law in energy with a slope of $3.8$. This is substantially different to that predicted by dark matter annihilation…

High Energy Astrophysical Phenomena · Physics 2020-04-01 Geoff Beck
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