English
Related papers

Related papers: A MeerKAT view on galaxy clusters

200 papers

Massive, merging galaxy clusters often host giant, diffuse radio sources that arise from shocks and turbulence; hence, radio observations can be useful for determining the merger state of a cluster. In preparation for a larger study, we…

Cosmological MHD simulations of galaxy cluster formation show a significant amplification of seed magnetic fields. We developed a novel method to decompose cluster magnetized turbulence into modes and showed that the fraction of the fast…

Astrophysics of Galaxies · Physics 2015-06-12 Andrey Beresnyak , Hao Xu , Hui Li , Reinhard Schlickeiser

Low-frequency radio observations of galaxy clusters are the key to detecting the diffuse extended emission associated with them. The presence and properties of such radio sources in galaxy clusters reveal the existence of magnetic fields on…

Astrophysics · Physics 2009-11-13 R. F. Pizzo , A. G. de Bruyn , L. Feretti , F. Govoni

A significant fraction of galaxy clusters exhibits cluster wide radio halos. We give a simple prediction of the local and higher redshift radio halo luminosity function (RHLF) on the basis of (i) an observed and a theoretical X-ray cluster…

Astrophysics · Physics 2009-11-07 Torsten A. Ensslin , Huub Roettgering

We investigate the possibility that radio halos of clusters of galaxies are caused by synchrotron emission of cosmic ray electrons (CRe), which were produced by cosmic ray protons (CRp) interacting hadronically with the intra-cluster medium…

Astrophysics · Physics 2011-05-23 Klaus Dolag , Torsten A. Ensslin

Galaxy clusters with signs for a recent merger show in many cases extended diffuse radio features. This emission originates from relativistic electrons which suffer synchrotron losses due to the intra-cluster magnetic field. The mechanisms…

Astrophysics of Galaxies · Physics 2015-02-11 A. Drabent , M. Hoeft , R. F. Pizzo , A. Bonafede , R. J. van Weeren , U. Klein

The thermal plasma of galaxy clusters lost most of its information on how structure formation proceeded as a result of dissipative processes. In contrast, non-equilibrium distributions of cosmic rays (CR) preserve the information about…

Astrophysics · Physics 2009-11-13 Christoph Pfrommer , Torsten A. Ensslin , Volker Springel

We use the results from a constrained, cosmological MHD simulation of the Local Universe to predict the radio halo and the gamma-ray flux from the Coma cluster and compare it to current observations. The simulated magnetic field within the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 J. Donnert , K. Dolag , G. Brunetti , R. Cassano , A. Bonafede

We examine the possible acceleration mechanisms of the relativistic particles responsible for the extended radio emission in Abell 520. We used new LOFAR 145 MHz, archival GMRT 323 MHz and VLA 1.5 GHz data to study the morphological and…

Observations of diffuse, non-thermal radio emission spanning several megaparsecs have been documented in over 100 galaxy clusters. This emission, classified as giant radio halos (GHs), mini halos, and radio relics based mainly on their…

High Energy Astrophysical Phenomena · Physics 2024-04-23 Doron Kushnir , Uri Keshet , Eli Waxman

Detecting diffuse radio emission, such as from halos, in galaxy clusters is crucial for understanding large-scale structure formation in the universe. Traditional methods, which rely on X-ray and Sunyaev-Zeldovich (SZ) cluster…

Astrophysics of Galaxies · Physics 2025-06-04 Ashutosh K. Mishra , Emma Tolley , Shreyam Parth Krishna , Jean-Paul Kneib

Galaxy clusters are unique laboratories to investigate turbulent fluid motions and large scale magnetic fields. Synchrotron radio halos at the center of merging galaxy clusters provide the most spectacular and direct evidence of the…

Context. Radio halos are megaparsec-scale diffuse radio sources{ mostly} located at the centres of merging galaxy clusters. The common mechanism invoked to explain their origin is the re-acceleration of relativistic particles caused by…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-27 G. Di Gennaro , R. J. van Weeren , R. Cassano , G. Brunetti , M. Brüggen , M. Hoeft , E. Osinga , A. Botteon , V. Cuciti , F. de Gasperin , H. J. A. Röttgering , C. Tasse

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 have performed 323 MHz observations with the Giant Metrewave Radio Telescope of the most promising candidates selected from the MACS catalog. The aim of the work is to extend our knowledge of the radio halo and relic populations to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 A. Bonafede , M Brueggen , R. van Weeren , F. Vazza , G. Giovannini , H. Ebeling , A. C. Edge , M. Hoeft , U. Klein

Deep radio observations of galaxy clusters have revealed the existence of diffuse radio sources ("halos" and "relics") related to the presence of relativistic electrons and weak magnetic fields in the intracluster volume. I will outline our…

Cosmology and Nongalactic Astrophysics · Physics 2009-06-25 C. Ferrari

Many galaxy clusters host Megaparsec-scale radio halos, generated by ultrarelativistic electrons in the magnetized intracluster medium. Correlations between the power of radio halos and the thermal properties of the hosting clusters were…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 R. Cassano , S. Ettori , G. Brunetti , S. Giacintucci , G. W. Pratt , T. Venturi , R. Kale , K. Dolag , M. Markevitch

Galaxy clusters are assembled via merging of smaller structures, in a process that generates shocks and turbulence in the intra cluster medium and produces radio diffuse emission in the form of halos and relics. The cluster pair A399-A401…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-17 C. D. Nunhokee , G. Bernardi , S. Manti , F. Govoni , A. Bonafede , T. Venturi , D. Dallacasa , M. Murgia , E. Orrú , R. F. Pizzo , O. M. Smirnov , V. Vacca

Radio relics are giant sources of diffuse synchrotron radio emission in the outskirts of galaxy clusters that are associated with shocks in the intracluster medium. Still, the origin of relativistic particles that make up relics is not…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-10 David C. Smolinski , Denis Wittor , Franco Vazza , Marcus Brüggen

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
‹ Prev 1 4 5 6 7 8 10 Next ›