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相关论文: Diffuse radio emission in the Coma cluster

200 篇论文

In some clusters of galaxies, a diffuse non-thermal emission is present, not obviously associated with any individual galaxy. These sources have been identified as relics, mini-halos, and halos according to their properties and position…

宇宙学与河外天体物理 · 物理学 2015-05-18 G. Giovannini , A. Bonafede , L. Feretti , F. Govoni , M. Murgia

The Intra-Cluster Medium is characterized by thermal emission, and by the presence of large scale magnetic fields. In some clusters of galaxies a diffuse non-thermal emission is also present, located at the cluster center and named radio…

宇宙学与河外天体物理 · 物理学 2015-05-14 G. Giovannini , A. Bonafede , L. Feretti , F. Govoni , M. Murgia , F. Ferrari , G. Monti

We have used the upgraded Giant Metrewave Radio Telescope to map the Coma cluster of galaxies at 250-500 MHz and 1050-1450 MHz bands. These 6.26 arcsec and 2.18 arcsec resolutions observations allow detailed radio structures to be…

星系天体物理 · 物理学 2021-06-01 Dharam V. Lal

Radio halos are elusive sources located at the center of merging galaxy clusters. To date, only about 40 radio halos are known, thus the discovery of new halos provide important insights on this class of sources. To improve the statistics…

宇宙学与河外天体物理 · 物理学 2015-06-05 F. Govoni , C. Ferrari , L. Feretti , V. Vacca , M. Murgia , G. Giovannini , R. Perley , C. Benoist

The presence of non-thermal components in galaxy clusters is now clearly established. Diffuse radio emission from the Intra Cluster Medium (ICM) of several galaxy clusters is revealed in the form of radio halos and relics. These emissions…

宇宙学与河外天体物理 · 物理学 2009-02-18 Rossella Cassano

We report the discovery of a luminous, mini radio halo of ~240 kpc dimension at the center of a distant cluster of galaxies at redshift z = 0.131. Our optical and multi-wavelength GMRT and VLA observations reveal a highly unusual structure…

宇宙学与河外天体物理 · 物理学 2009-03-03 Joydeep Bagchi , Joe Jacob , Gopal-Krishna , Nitin Wadnerkar , J. Belapure , Norbert Werner , A. C. Kumbharkhane

New radio data are presented for the clusters A401, A545, A754, A1914, A2219 and A2390, where the presence of diffuse radio emission was suggested from the images of the NRAO VLA Sky Survey. Sensitive images of these clusters, obtained with…

天体物理学 · 物理学 2011-05-23 M. Bacchi , L. Feretti , G. Giovannini , F. Govoni

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…

天体物理学 · 物理学 2009-11-06 F. Govoni , T. A. Ensslin , L. Feretti , G. Giovannini

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…

星系天体物理 · 物理学 2016-11-23 Viral Parekh , K. S. Dwarakanath , Ruta Kale , Huib Intema

A very important aspect of the radio emission from galaxy clusters is represented by the diffuse radio sources associated with the intracluster medium: radio halos and relics. These radio sources indicate the existence of large scale…

天体物理学 · 物理学 2007-05-23 Luigina Feretti

Non-thermal properties of galaxy clusters have been studied with detailed and deep radio images in comparison with X-ray data. While much progress has been made, most of the studied clusters are at a relatively low redshift (z < 0.3). We…

宇宙学与河外天体物理 · 物理学 2020-08-26 G. Giovannini , M. Cau , A. Bonafede , H. Ebeling , L. Feretti , M. Girardi , M. Gitti , F. Govoni , A. Ignesti , M. Murgia , G. B. Taylor , V. Vacca

The study of diffuse radio sources is essential to our knowledge of the physical conditions in clusters of galaxies and of the role that large scale magnetic fields play in the propagation of the relativistic particles in the intracluster…

高能天体物理现象 · 物理学 2013-09-30 Nonis , Stavros , Gizani , Nectaria A. B

We present deep 1.4GHz Very Large Array (VLA) radio continuum observations of two ~half square degree fields in the Coma cluster of galaxies. The two fields, "Coma 1" and "Coma 3," correspond to the cluster core and southwest infall region…

宇宙学与河外天体物理 · 物理学 2009-11-13 Neal A. Miller , Ann E. Hornschemeier , Bahram Mobasher

The Coma cluster exhibits evidence for a high-energetic non-thermal particle population. At frequencies >1 GHz recent radio halo observations confirm a significant spectral steepening of the volume-integrated emission. We calculate the…

天体物理学 · 物理学 2009-11-10 A. Reimer , O. Reimer , R. Schlickeiser , A. Iyudin

We report the detection of a diffuse radio halo source in the hottest known cluster of galaxies 1E0658-56 (RXJ0658-5557). The radio halo has a morphology similar to the X-ray emission from the hot intracluster medium. The detection of such…

天体物理学 · 物理学 2007-05-23 H. Liang

We combine all available information about the spectral shape and morphology of the radio halo of the Coma cluster with the gamma-ray upper limits obtained by the Fermi-LAT and with the magnetic field strength derived from Faraday rotation…

高能天体物理现象 · 物理学 2015-06-05 G. Brunetti , P. Blasi , O. Reimer , L. Rudnick , A. Bonafede , S. Brown

Radio halos are faint radio sources usually located at the center of merging clusters of galaxies. These diffuse radio sources are rare, having so far been found only in about 30 clusters of galaxies, suggesting that particular conditions…

宇宙学与河外天体物理 · 物理学 2015-05-14 M. Murgia , F. Govoni , L. Feretti , G. Giovannini

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…

宇宙学与河外天体物理 · 物理学 2017-11-01 J. G. Albert , C. Sifón , A. Stroe , F. Mernier , H. T. Intema , H. J. A. Röttgering , G. Brunetti

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…

天体物理学 · 物理学 2007-05-23 Torsten A. Ensslin

We present new arcminute resolution radio images of the low surface brightness radio source PKS B1400-33 that is located in the poor cluster Abell S753. The observations consist of 330 MHz VLA, 843 MHz MOST and 1398 and 2378 MHz ATCA data.…

天体物理学 · 物理学 2009-11-07 R. Subrahmanyan , A. J. Beasley , W. M. Goss , K. Golap , R. W. Hunstead