English
Related papers

Related papers: Diffuse radio emission in the complex merging gala…

200 papers

Diffuse radio emission has been detected in a considerable number of galaxy clusters and groups, revealing the presence of pervasive cosmic magnetic fields, and of relativistic particles in the large-scale structure (LSS) of the Universe.…

We present radio observations of the galaxy cluster PLCK G004.5-19.5 ($z=0.52$) using the Giant Metrewave Radio Telescope at 150~MHz, 325~MHz, and 610~MHz. We find an unusual arrangement of diffuse radio emission in the center and periphery…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-01 J. G. Albert , C. Sifón , A. Stroe , F. Mernier , H. T. Intema , H. J. A. Röttgering , G. Brunetti

Shock waves generated during cluster mergers offer a powerful probe of how large-scale structure grows and evolves in the Universe. As part of the MeerKAT-South Pole Telescope (SPT) survey, we report the discovery of a single arc-like radio…

Deep Very Large Array radio observations confirm the presence of halo and relic sources in six clusters of galaxies (A115, A520, A773, A1664, A2254, A2744) where a wide diffuse emission was previously found in the NRAO VLA Sky Survey. New…

Astrophysics · Physics 2009-11-06 F. Govoni , L. Feretti , G. Giovannini , H. Bohringer , T. H. Reiprich , M. Murgia

We present LOFAR observations of one of the most spectacular objects in the radio sky: Abell 2255. This is a nearby ($z = 0.0806$) merging galaxy cluster hosting one of the first radio halos ever detected in the intra-cluster medium (ICM).…

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…

We present the results of a Chandra observation of the cooling core cluster Abell 2063. Spectral analysis shows that there is cool gas (2 keV) associated with the cluster core, which is more than a factor of 2 cooler than the outer cluster…

Astrophysics · Physics 2008-11-26 Kalin N. Kanov , Craig L. Sarazin , Amalia K. Hicks

We discuss the statistical properties of the radio halo population in galaxy clusters. Radio bi-modality is observed in galaxy clusters: a fraction of clusters host giant radio halos while the majority of clusters do not show evidence of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 R. Cassano , G. Brunetti , T. Venturi

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

We present new measurements of the diffuse radio emission from the Coma cluster of galaxies at 1.4 GHz using the Effelsberg 100-m-telescope. The halo source Coma C has an extent down to noise of about 80 arcmin corresponding to 3 Mpc (H_0 =…

Astrophysics · Physics 2007-05-23 B. M. Deiss , W. Reich , H. Lesch , R. Wielebinski

Non-thermal components in the intra-cluster medium (ICM) such as turbulence, magnetic field, and cosmic rays imprint the past and current energetic activities of jets from active galactic neuclie (AGN) of member galaxies as well as…

High Energy Astrophysical Phenomena · Physics 2023-11-16 Kohei Kurahara , Takuya Akahori , Aika Oki , Yuki Omiya , Kazuhiro Nakazawa

Here we analyze radio, optical, and X-ray data for a peculiar cluster Abell 578. This cluster is not fully relaxed and consists of two merging sub-systems. The brightest cluster galaxy, CGPG 0719.8+6704, is a pair of interacting ellipticals…

High Energy Astrophysical Phenomena · Physics 2015-06-03 K. Hagino , L. Stawarz , A. Siemiginowska , C. C. Cheung , D. Koziel-Wierzbowska , A. Szostek , G. Madejski , D. E. Harris , A. Simionescu , T. Takahashi

Merging galaxy clusters produce low Mach number shocks in the intracluster medium. These shocks can accelerate electrons to relativistic energies that are detectable at radio frequencies. MACS J0744.9+3927 is a massive ($M_{500} = (11.8 \pm…

In the present-day Universe, magnetic fields pervade galaxy clusters, with strengths of a few microGauss obtained from Faraday Rotation. Evidence for cluster magnetic fields is also provided by Megaparsec-scale radio emission, namely radio…

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

The goal of the present study is to extend our current knowledge of the diffuse radio source (halo and relic) populations to $z$ $>$ 0.3. Here we report GMRT and EVLA radio observations of six galaxy clusters taken from the MAssive Cluster…

Astrophysics of Galaxies · Physics 2016-11-23 Viral Parekh , K. S. Dwarakanath , Ruta Kale , Huib Intema

In the course of the formation of cosmological structures, large shock waves are generated in the intra-cluster medium. In analogy to processes in supernova remnants, these shock waves may generate a significant population of relativistic…

Astrophysics · Physics 2008-11-26 Matthias Hoeft , Marcus Brueggen

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 present the analysis of our 13 and 22 cm ATCA observations of the central region of the merging galaxy cluster A3921 (z=0.094). We investigated the effects of the major merger between two sub-clusters on the star formation (SF) and radio…

Astrophysics · Physics 2009-11-11 C. Ferrari , R. W. Hunstead , L. Feretti , S. Maurogordato , S. Schindler

Observations of giant radio halos provide unambiguous evidence for the existence of cosmic ray (CR) electrons and magnetic fields in galaxy clusters. The physical mechanism generating radio halos is still heavily debated. We critically…

High Energy Astrophysical Phenomena · Physics 2011-09-28 Christoph Pfrommer , Torsten Ensslin , Francesco Miniati , Kandaswamy Subramanian
‹ Prev 1 8 9 10 Next ›