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Related papers: A MeerKAT view on galaxy clusters

200 papers

Giant radio halos are Mpc-size sources found in some merging galaxy clusters. The synchrotron emitting electrons are thought to be (re)accelerated by plasma turbulence induced by the merging of two massive clusters. Cool core galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 A. Bonafede , H. T. Intema , M. Brüggen , H. R. Russell , G. Ogrean , K. Basu , M. Sommer , R. J. van Weeren , R. Cassano , A. C. Fabian , H. J. A. Röttgering

Collisions of galaxy clusters generate shocks and turbulence in the intra-cluster medium (ICM). The presence of relativistic particles and magnetic fields is inferred through the detection of extended synchrotron radio sources such as…

Radio relics are synchrotron emission found on the periphery of galaxy clusters. From the position and the morphology, it is often believed that the relics are generated by cosmic-ray (CR) electrons accelerated at shocks through a diffusive…

High Energy Astrophysical Phenomena · Physics 2015-12-29 Yutaka Fujita , Motokazu Takizawa , Ryo Yamazaki , Hiroki Akamatsu , Hiroshi Ohno

Galaxy clusters are the most massive constituents of the large-scale structure of the Universe. While the hot thermal gas that pervades galaxy clusters is relatively well understood through observations with X-ray satellites, our…

High Energy Astrophysical Phenomena · Physics 2017-10-19 F. de Gasperin , H. T. Intema , T. W. Shimwell , G. Brunetti , M. Bruggen , T. A. Ensslin , R. J. van Weeren , A. Bonafede , H. J. A. Rottgering

Recent improvements in the capabilities of low frequency radio telescopes provide a unique opportunity to study thermal and non-thermal properties of the cosmic web. We argue that the diffuse, polarized emission from giant radio relics…

Astrophysics · Physics 2011-03-18 N. Battaglia , C. Pfrommer , J. L. Sievers , J. R. Bond , T. A. Ensslin

Radio halos are megaparsec-scale diffuse, non-thermal radio sources located at the centers of galaxy clusters, tracing relativistic particles and magnetic fields in the intra-cluster medium. Their origin is generally attributed to cluster…

A new model for the, so called, `cluster radio relics' is presented (Ensslin & Gopal-Krishna 2000). Fossil radio cocoons, resulting from the former activity of radio galaxies, should contain a low energy relativistic electron population and…

Astrophysics · Physics 2007-05-23 Torsten A. Ensslin , Gopal-Krishna

Clusters of galaxies are sites of acceleration of charged particles and sources of non-thermal radiation. We report on new constraints on the population of cosmic rays in the Intra Cluster Medium (ICM) obtained via radio observations of a…

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

Low-mass ($M_{\rm{500}}<5\times10^{14}{\rm{M_\odot}}$) galaxy clusters have been largely unexplored in radio observations, due to the inadequate sensitivity of existing telescopes. However, the upgraded GMRT (uGMRT) and the Low Frequency…

In this paper we investigate a situation where relativistic particles are reaccelerated diffusing across regions of reconnection and magnetic dynamo in super-Alfvenic, incompressible large-scale turbulence. We present an exploratory study…

High Energy Astrophysical Phenomena · Physics 2016-03-23 G. Brunetti , A. Lazarian

The first detection of a diffuse radio source in a cluster of galaxies, dates back to the 1959 (Coma Cluster, Large et al. 1959). Since then, synchrotron radiating radio sources have been found in several clusters, and represent an…

High Energy Astrophysical Phenomena · Physics 2015-05-27 L. Feretti , G. Giovannini , F. Govoni , M. Murgia

We report the discovery of 164 compact (radius < 1 arcmin) radio rings using MeerKAT 1.3 GHz data from the SARAO MeerKAT Galactic Plane Survey (l=2-60deg, 252-358deg, |b|<1.5deg) and the Galactic Centre mosaic, from a search aimed at…

Large-scale diffuse radio emission is observed in some clusters of galaxies. There is ample of evidence that the emission has its origin in synchrotron losses of relativistic electrons, accelerated in the course of clusters mergers. In a…

Astrophysics · Physics 2009-11-13 M. Hoeft , M. Brueggen , G. Yepes , S. Gottloeber , A. Schwope

We present deep 1.1-3.1 GHz Australia Telescope Compact Array observations of the radio halo of the bullet cluster, 1E 0657-55.8. In comparison to existing images of this radio halo the detection in our images is at higher significance. The…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Timothy W. Shimwell , Shea Brown , Ilana J. Feain , Luigina Feretti , B. M. Gaensler , Craig Lage

The strong activity of radio galaxies should have led to a nearly ubiquitous presence of fossil radio plasma in the denser regions of the inter-galactic medium as clusters, groups and filaments of galaxies. This fossil radio plasma can…

Astrophysics · Physics 2007-05-23 Torsten A. Ensslin

Radio galaxies play an important role in the seeding of cosmic rays and magnetic fields in galaxy clusters. Here, we simulate the evolution of relativistic electrons injected into the intracluster medium by radio galaxies. Using passive…

High Energy Astrophysical Phenomena · Physics 2021-09-15 F. Vazza , D. Wittor , G. Brunetti , M. Brüggen

We propose the model describing the observed multiple fast radio bursts due to the close encounters and collisions of neutron stars in the central clusters of the evolved galactic nuclei. The subsystem of neutron star cluster may originate…

High Energy Astrophysical Phenomena · Physics 2017-12-07 V. I. Dokuchaev , Yu. N. Eroshenko

Diffuse radio emission in galaxy clusters is known to be related to cluster mass and cluster dynamical state. We collect the observed fluxes of radio halos, relics, and mini-halos for a sample of galaxy clusters from the literature, and…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-24 Z. S. Yuan , J. L. Han , Z. L. Wen

Globular clusters are known to host an unusually large population of millisecond pulsar when compared to the Galactic disk. This is thanks to the high rate of dynamical encounters occurring in the clusters that can create the conditions to…

High Energy Astrophysical Phenomena · Physics 2021-12-14 F. Abbate

Abell 754 is a rich galaxy cluster at $z=0.0543$ and is considered the prototype of a major cluster merger. Like many dynamically unrelaxed systems, it hosts diffuse radio emission on Mpc-scales. Extended synchrotron sources in the…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-16 A. Botteon , R. J. van Weeren , D. Eckert , F. Gastaldello , M. Markevitch , S. Giacintucci , G. Brunetti , R. Kale , T. Venturi
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