English
Related papers

Related papers: Non-thermal phenomena in galaxies clusters

200 papers

The radiative cooling time of the X-ray-emitting plasma near the center in many clusters of galaxies is shorter than the age of the cluster, but neither the expected large drop in central temperature --nor the expected mass flow towards the…

Astrophysics · Physics 2009-11-07 Sergio Colafrancesco , Arnon Dar , Alvaro De Rujula

The brightest cluster radio halo known resides in the Coma cluster of galaxies. The relativistic electrons producing this diffuse synchrotron emission should also produce inverse Compton emission that becomes competitive with thermal…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-11 Daniel R. Wik , Craig L. Sarazin , Alexis Finoguenov , Kyoko Matsushita , Kazuhiro Nakazawa , Tracy E. Clarke

We present results on the spectroscopic analysis of XMM-Newton EPIC data of the central 0.5/h_50 Mpc regions of the clusters of galaxies Coma, A1795 and A3112. The temperature of the hot intracluster gas as determined by modeling the 2 - 7…

Astrophysics · Physics 2009-11-07 J. Nevalainen , R. Lieu , M. Bonamente , D. Lumb

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

Merger and accretion shocks in clusters of galaxies can accelerate particles via first order Fermi process. Since this mechanism is believed to be intrinsically efficient, shocks are expected to be modified by the backreaction of the…

Astrophysics · Physics 2009-11-10 Stefano Gabici , Pasquale Blasi

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 gas in the cores of many clusters and groups of galaxies has a short radiative cooling time. Energy from the central black hole is observed to flow into this gas by means of jets, bubbles and sound waves. Cooling is thus offset by…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 A. C. Fabian , J. S. Sanders

The nonthermal phenomena in clusters of galaxies are considered in the context of the hierarchical model of cosmic structure formation by accretion and merging of the dark matter (DM) substructures.Accretion and merging processes produce…

Astrophysics · Physics 2009-11-10 A. M. Bykov

The origin of hard X-ray (HXR) excess emission from clusters of galaxies is still an enigma, whose nature is debated. One of the possible mechanism to produce this emission is the bremsstrahlung model. However, previous analytical and…

High Energy Astrophysical Phenomena · Physics 2015-06-11 D. O. Chernyshov , V. A. Dogiel , C. M. Ko

Results from the Suzaku X-ray broad-band observations of clusters of galaxies are summarized. Aiming at understanding the physics of gas heating/particle acceleration and the cluster dynamical evolution, we search for non-thermal hard X-ray…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-25 Naomi Ota

This paper studied the faint, diffuse extended X-ray emission associated with the radio lobes and the hot gas in the intracluster medium (ICM) environment for a sample of radio galaxies. We used shallow ($\sim 10$ ks) archival Chandra…

Cooling flows are regions where the importance of non-thermal intra-cluster medium components such as magnetic fields and cosmic rays may be strongest within a galaxy cluster. They are also regions where such components are best detectable…

Astrophysics · Physics 2007-05-23 Torsten Ensslin , Corina Vogt , Christoph Pfrommer

Clusters of galaxies can be seen as giant astrophysical laboratories enclosing matter in a large enough volume, so that the matter composition can be taken as representing the composition of our Universe. X-ray observations allow a very…

Astrophysics · Physics 2007-05-23 Hans Boehringer

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

We consider the non-radial motions, originating in the outskirts of clusters of galaxies and we show how it may reduce the discrepancy between Cold Dark Matter (CDM) predicted X-ray temperature distribution function of clusters of galaxies…

Astrophysics · Physics 2007-05-23 A. Del Popolo , M. Gambera

Electrons at relativistic speeds, diffusing in magnetic fields, cause copious emission at radio frequencies in both clusters of galaxies and radio galaxies, through the non-thermal radiation emission called synchrotron. However, the total…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-28 Siddharth Malu , Abhirup Datta , Sergio Colafrancesco , Paolo Marchegiani , Ravi Subrahmanyan , D Narasimha , Mark H. Wieringa

Radio observations discovered large scale non thermal sources in the central Mpc regions of dynamically disturbed galaxy clusters (radio halos). The morphological and spectral properties of these sources suggest that the emitting electrons…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-05 G. Brunetti , R. Cassano

Early X-ray observations suggested that the intracluster medium cools and condenses at the centers of clusters, leading to a cooling flow of plasma in the cluster core. The increased incidence of emission-line nebulosity, excess blue light,…

Astrophysics · Physics 2007-05-23 Megan Donahue , G. Mark Voit

Clusters of galaxies contain a hot gas, which emits in X-rays. X-ray telescopes such as XMM-Newton allow to study this plasma to obtain information on physical quantities of these objects. We present here some results on the total mass…

Astrophysics · Physics 2007-05-23 D. M. Neumann , S. Majerowicz

We present an estimate of the X-ray background (XRB) spectrum from the warm-hot intergalactic medium (IGM) associated with groups and clusters of galaxies, using purely the observationally determined X-ray luminosity function (XLF) and…

Astrophysics · Physics 2009-11-06 Xiang-Ping Wu , Yan-Jie Xue