English
Related papers

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

200 papers

We report a discovery of a 1.3 Mpc diffuse radio source with extremely steep spectrum fading radio structures in the vicinity of the Abell 449 cluster of galaxies. Its extended diffuse lobes are bright only at low radio frequencies and…

Astrophysics of Galaxies · Physics 2016-02-11 D. Hunik , M. Jamrozy

Diffuse radio emission associated with the intra-cluster medium (ICM) is observed in a number of merging galaxy clusters. It is currently believed that in mergers a fraction of the kinetic energy is channeled into non-thermal components,…

We present new, multiwavelength Very Large Array observations of the 3 radio galaxies in the cluster Abell 119: 0053-015, 0053-016 and 3C 29. The first two radio galaxies, which lie close to the cluster center, show a narrow-angle-tailed…

Astrophysics · Physics 2007-05-23 L. Feretti , D. Dallacasa , F. Govoni , G. Giovannini , G. B. Taylor , U. Klein

Galaxy cluster mergers are natural consequences of the structure formation in the Universe. Such events involve a large amount of energy ($\sim 10^{63}$ erg) dissipated during the process. Part of this energy can be channelled in particle…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-06 M. Balboni , A. Bonafede , G. Bernardi , D. Wittor , F. Vazza , A. Botteon , E. Carretti , T. Shimwell , V. Vacca , R. J. van Weeren

In this paper we present a detailed study of the giant radio halo in the galaxy cluster Abell 697, with the aim to constrain its origin and connection with the cluster dynamics. We performed high sensitivity GMRT observations at 325 MHz,…

We present the first band-2 (120--250\,MHz) uGMRT (upgraded Giant Metrewave Radio Telescope) observations of the bimodal galaxy cluster Abell\,1644 (\(z = 0.0471\)), complemented by Chandra X-ray data. While weak lensing measurements reveal…

Astrophysics of Galaxies · Physics 2025-12-24 Humaira Bashir , R. Kale , Asif Iqbal , Manzoor A. Malik

We present results based on new Chandra and multi-frequency radio observations of the disturbed cool core cluster Abell 133. The diffuse gas has a complex bird-like morphology, with a plume of emission extending from two symmetric wing-like…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 S. W. Randall , T. E. Clarke , P. E. J. Nulsen , M. S. Owers , C. L. Sarazin , W. R. Forman , S. S. Murray

Giant radio halos are the most relevant examples of diffuse synchrotron emission from galaxy clusters. A number of these sources have very steep spectrum, with spectral index $\alpha \geq 1.5-1.6$ ($F(\nu) \propto \nu^{-\alpha}$), and are…

High Energy Astrophysical Phenomena · Physics 2015-05-14 G. Brunetti

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

We have detected a radio bridge of unpolarized synchrotron emission connecting the NW relic of the galaxy cluster Abell 3667 to its central regions. We used data at 2.3 GHz from the S-band Polarization All Sky Survey (S-PASS) and at 3.3 GHz…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 E. Carretti , S. Brown , L. Staveley-Smith , J. M. Malarecki , G. Bernardi , B. M. Gaensler , M. Haverkorn , M. J. Kesteven , S. Poppi

Radio observations over the last two decades have provided evidence that diffuse synchrotron emission in the form of megaparsec-scale radio halos in galaxy clusters is likely tracing regions of the intracluster medium where relativistic…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-25 G. Bernardi , T. Venturi , R. Cassano , D. Dallacasa , G. Brunetti , V. Cuciti , M. Johnston-Hollitt , N. Oozeer , O. M. Smirnov

We report the discovery of large-scale diffuse radio emission in the galaxy cluster MACS J1752.0+4440 (z=0.366). Using Westerbork Synthesis Radio Telescope (WSRT) observations we find that the cluster hosts a double radio relic system as…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 R. J. van Weeren , A. Bonafede , H. Ebeling , A. C. Edge , M. Bruggen , G. Giovannini , M. Hoeft , H. J. A. Rottgering

Aims. To study at multiple frequencies the radio emission arising from the massive galaxy cluster MACS J0717.5+3745 (z=0.55). Known to be an extremely complex cluster merger, the system is uniquely suited for an investigation of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 A. Bonafede , L. Feretti , G. Giovannini , F. Govoni , M. Murgia , G. B. Taylor , H. Ebeling , S. Allen , G. Gentile , Y. Pihlstrom

Clusters of galaxies may contain cluster-wide, centrally located, diffuse radio sources, called halos. They have been found to show morphologies similar to those of the X-ray emission. To quantify this qualitative statement we performed a…

Astrophysics · Physics 2009-11-06 F. Govoni , T. A. Ensslin , L. Feretti , G. Giovannini

In a recent paper we reported on the discovery of a radio halo with very steep spectrum in the merging galaxy cluster Abell 521 through observations with the Giant Metrewave Radio Telescope (GMRT). We showed that the steep spectrum of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 D. Dallacasa , G. Brunetti , S. Giacintucci , R. Cassano , T. Venturi , G. Macario , N. E. Kassim , W. Lane , G. Setti

Mergers between galaxy clusters often drive shocks into the intra cluster medium (ICM), the effects of which are sometimes visible via temperature and density jumps in the X-ray, and via radio emission from relativistic particles energized…

Some merging galaxy clusters host diffuse extended radio emission, so-called radio halos and relics. Here we present observations between 147 MHz and 4.9 GHz of a new radio-selected galaxy cluster 1RXS J0603.3+4214 (z=0.225). The cluster is…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 R. J. van Weeren , H. J. A. Rottgering , H. T. Intema , L. Rudnick , M. Bruggen , M. Hoeft , J. B. R. Oonk

Optical imaging and spectroscopic observations of the z = 0.245 double galaxy cluster Abell 2465 are described. This object appears to be undergoing a major merger. It is a double X-ray source and is detected in the radio at 1.4 GHz. This…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Gary A. Wegner

We report a detailed optical study of the clusters Abell 2125 and 2645. Both clusters have z=0.25 and richness class 4, yet contrast strongly in blue fraction and radio galaxy population. We find 27 spectroscopically confirmed radio…

Astrophysics · Physics 2009-10-31 F. N. Owen , M. J. Ledlow , W. C. Keel , G. E. Morrison

Synchrotron radio emission is being detected from an increasing number of galaxy clusters. Spectral index images are a powerful tool to investigate the origin, nature, and connection of these sources with the dynamical state of the cluster.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 V. Vacca , L. Feretti , G. Giovannini , F. Govoni , M. Murgia , R. A. Perley , T. E. Clarke