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Related papers: Nonthermal phenomena in clusters of galaxies

200 papers

Fermi has detected gamma-ray emission from eight globular clusters. We suggest that the gamma-ray emission from globular clusters may result from the inverse Compton scattering between relativistic electrons/positrons in the pulsar wind of…

High Energy Astrophysical Phenomena · Physics 2015-05-19 K. S. Cheng , D. O. Chernyshov , V. A. Dogiel , C. Y. Hui , A. K. H. Kong

Chandra images of galaxy clusters have revealed a wealth of structure unseen by previous generations of low resolution X-ray observatories. In the cores of clusters, bright, irregular X-ray emission is now routinely seen within central…

Astrophysics · Physics 2007-05-23 B. R. McNamara

We analyse new results of Chandra and Suzaku which found a flux of hard X-ray emission from the compact region around Sgr A$^\ast$ (r ~ 100 pc). We suppose that this emission is generated by accretion processes onto the central supermassive…

We argue that the observed correlation between the radio luminosity and the X-ray luminosity in radio emitting galaxy clusters implies that the radio emission is due to secondary electrons that are produced by p-p interactions and lose…

High Energy Astrophysical Phenomena · Physics 2010-02-22 Doron Kushnir , Boaz Katz , Eli Waxman

(Abridged) We investigate the spectral distortion of the cosmic microwave background (CMB) caused by relativistic plasma. Within the Thomson regime, an exact analytic expression for the photon scattering kernel of a momentum power-law…

Astrophysics · Physics 2011-05-23 Torsten A. Ensslin , Christian R. Kaiser

X-ray spectra of galaxy clusters are dominated by the thermal emission from the hot intracluster medium. In some cases, besides the thermal component, spectral models require additional components associated, e.g., with resonant scattering…

High Energy Astrophysical Phenomena · Physics 2018-11-07 Liyi Gu , Irina Zhuravleva , Eugene Churazov , Frits Paerels , Jelle Kaastra , Hiroya Yamaguchi

The thermodynamics of the diffuse, X-ray emitting gas in clusters and groups of galaxies are affected by a certain amount of non-gravitational energy input, as indicated by the scaling properties of X-ray halos. Such a view has been…

Astrophysics · Physics 2007-05-23 Paolo Tozzi , Colin Norman

The detection of diffuse radio emission associated with clusters of galaxies indicates populations of relativistic leptons infusing the intracluster medium. Those electrons and positrons are either injected into and accelerated directly in…

High Energy Astrophysical Phenomena · Physics 2015-05-19 M. Ackermann et al.

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

Integrated X-ray spectra of an evolving population of starburst galaxies (SBGs) are determined based on the observed spectra of local SBGs. In addition to emission from hot gas and binary systems, our model SBG spectrum includes a…

Astrophysics · Physics 2009-11-07 M. Persic , Y. Rephaeli

We present sensitive, high-resolution, X-ray imaging from Chandra of the high-redshift radio galaxy 4C 41.17 (z=3.8). Our 150-ks Chandra exposure detects strong X-ray emission from a point source coincident with the nucleus of the radio…

Astrophysics · Physics 2009-11-07 C. A. Scharf , I. Smail , R. Ivison , R. G. Bower , W. van Breugel , M. Reuland

Several cool-core clusters are known to host a radio mini-halo, a diffuse, steep-spectrum radio source located in their cores, thus probing the presence of non-thermal components as magnetic field and relativistic particles on scales not…

High Energy Astrophysical Phenomena · Physics 2018-08-01 Alessandro Ignesti , Gianfranco Brunetti , Myriam Gitti , Simona Giacintucci

We use deep archival Chandra and XMM-Newton observations of three of the brightest cluster-centre radio galaxies in the sky, Cygnus A, Hercules A and Hydra A, to search for inverse-Compton emission from the population of electrons…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 M. J. Hardcastle , J. H. Croston

The X-ray background intensity around Lick count galaxies and rich clusters of galaxies is investigated in three ROSAT energy bands. It is found that the X-ray enhancements surrounding concentrations of galaxies exhibit significantly softer…

Astrophysics · Physics 2009-11-07 A. M. Soltan , M. J. Freyberg , G. Hasinger

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…

Astrophysics · Physics 2009-11-10 A. Reimer , O. Reimer , R. Schlickeiser , A. Iyudin

See comments. We calculate analytically an effect of the thermal Comptonization on the cosmic microwave background (CMB) photons when they propagate through galaxy clusters. We estimate a deformation of the CMB spectrum due to multiple…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-26 Lev Titarchuk , Galina Lipunova

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

Deep radio observations of galaxy clusters have revealed the existence of diffuse radio sources related to the presence of relativistic electrons and weak magnetic fields in the intracluster volume. The role played by this non-thermal…

Analyses of Chandra's first images of cooling flow clusters find smaller cooling rates than previously thought. Cooling may be occurring preferentially near regions of star formation in central cluster galaxies, where the local cooling and…

Astrophysics · Physics 2007-05-23 B. R. McNamara

The emission processes responsible for the observed X-rays from radio jets are commonly believed to be non-thermal, but in any particular case, it is unclear if synchrotron emission or one or more varieties of inverse Compton emission…

Astrophysics · Physics 2009-11-07 D. E. Harris , H. Krawczynski