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相关论文: Modeling radio mini-halos in cooling flow clusters

200 篇论文

We investigate radiatively inefficient accretion flow models for Sgr A*, the supermassive black hole in our Galactic Center, in light of new observational constraints. Confirmation of linear polarization in the submm emission argues for…

天体物理学 · 物理学 2009-11-07 Feng Yuan , Eliot Quataert , Ramesh Narayan

We compute 3D gasdynamical models of jet outflows from the central AGN, that carry mass as well as energy to the hot gas in galaxy clusters and groups. These flows have many attractive attributes for solving the cooling flow problem: why…

宇宙学与河外天体物理 · 物理学 2015-05-14 M. Gaspari , C. Melioli , F. Brighenti , A. D'Ercole

VLA deep radio images at 1.4 GHz in total intensity and polarization reveal a diffuse non-thermal source in the interacting clusters A3411 - A3412. Moreover a small-size low power radio halo at the center of the merging cluster A3411 is…

宇宙学与河外天体物理 · 物理学 2015-06-16 G. Giovannini , V. Vacca , M. Girardi , L. Feretti , F. Govoni , M. Murgia

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

The most important evidence of non-thermal phenomena in galaxy clusters comes from Giant Radio Halos (GRHs), synchrotron radio sources extended over Mpc scales, detected in a growing number of massive galaxy clusters. A promising…

天体物理学 · 物理学 2009-11-11 R. Cassano , G. Brunetti , G. Setti

We analyze sensitive, high-dynamic-range, observations to search for extended, diffuse, radio emission in relaxed and cool-core galaxy clusters. We performed deep 1.4 GHz Very Large Array observations, of A1068, A1413, A1650, A1835, A2029,…

宇宙学与河外天体物理 · 物理学 2015-05-13 F. Govoni , M. Murgia , M. Markevitch , L. Feretti , G. Giovannini , G. B. Taylor , E. Carretti

In a growing number of galaxy clusters diffuse extended radio sources have been found. These sources are not directly associated with individual cluster galaxies. The radio emission reveal the presence of cosmic rays and magnetic fields in…

高能天体物理现象 · 物理学 2019-02-13 R. J. van Weeren , F. de Gasperin , H. Akamatsu , M. Brüggen , L. Feretti , H. Kang , A. Stroe , F. Zandanel

We present a first attempt to investigate the origin of radio-emitting electrons in the newly discovered class of mega radio halos in clusters of galaxies. We study the evolution of relativistic electrons accreted by the external regions of…

高能天体物理现象 · 物理学 2023-10-02 L. Beduzzi , F. Vazza , G. Brunetti , V. Cuciti , D. Wittor , E. M. Corsini

There is a growing evidence that extended radio halos are most likely generated by electrons reaccelerated via some kind of turbulence generated in the cluster volume during major mergers. It is well known that Alfv\'en waves channel most…

天体物理学 · 物理学 2014-10-13 Gianfranco Brunetti , Pasquale Blasi , Rossella Cassano , Stefano Gabici

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

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…

天体物理学 · 物理学 2009-11-13 M. Hoeft , M. Brueggen , G. Yepes , S. Gottloeber , A. Schwope

We present high resolution ROSAT x-ray and radio observations of three cooling flow clusters containing steep spectrum radio sources at their cores. All three systems exhibit strong signs of interaction between the radio plasma and the hot…

天体物理学 · 物理学 2009-10-31 E. Rizza , C. Loken , M. Bliton , K. Roettiger , J. O. Burns , F. N. Owen

Radio relics are Mpc-sized synchrotron sources located in the peripheral regions of galaxy clusters. Models based on the diffuse shock acceleration (DSA) scenario have been widely accepted to explain the formation of radio relics. However,…

宇宙学与河外天体物理 · 物理学 2022-10-05 Yihao Zhou , Haiguang Xu , Zhenghao Zhu , Yuanyuan Zhao , Shida Fan , Chenxi Shan , Yongkai Zhu , Lei Hao , Li Ji , Zhongli Zhang , Xianzhong Zheng

The organization of this paper is as follows: the basic formulae used to derive the age of synchrotron sources and the equipartition parameters are presented in Section 2, while the observational properties of diffuse radio sources (Radio…

天体物理学 · 物理学 2015-06-24 Luigina Feretti , Gabriele Giovannini

Cooling flows are common in galaxy clusters which have cool cores. The soft X-ray emission below 1 keV from the flows is mostly absorbed by cold dusty gas within the central cooling sites. Further evidence for this process is presented here…

It is generally argued that most clusters of galaxies host cooling flows in which radiative cooling in the centre causes a slow inflow. However, recent observations by Chandra and XMM conflict with the predicted cooling flow rates. Amongst…

天体物理学 · 物理学 2009-11-07 M. Bruggen

Recent results on the radio emission from galaxy clusters are reviewed, with emphasis both on the radio galaxies and on the diffuse radio emission from the intracluster medium. We show that the formation of the tailed morphology in cluster…

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

We present new deep, high-resolution radio images of the diffuse minihalo in the cool core of the galaxy cluster RX J1720.1+2638. The images have been obtained with the Giant Metrewave Radio Telescope at 317, 617 and 1280 MHz and with the…

Radio halos are extended and diffuse non-thermal radio sources present at the cluster center, not obviously associated with any individual galaxy. A strong correlation has been found between the cluster X-ray luminosity and the halo radio…

宇宙学与河外天体物理 · 物理学 2015-05-27 G. Giovannini , L. Feretti , M. Girardi , F. Govoni , M. Murgia , V. Vacca , J. Bagchi

We present a study of the cavity system in the galaxy cluster RBS 797 based on Chandra and VLA data. RBS 797 (z = 0.35), is one of the most distant galaxy clusters in which two pronounced X-ray cavities have been discovered. The Chandra…

宇宙学与河外天体物理 · 物理学 2015-06-04 Alberto Doria , Myriam Gitti , Stefano Ettori , Fabrizio Brighenti , Paul E. J. Nulsen , Brian R. McNamara