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Related papers: Excess Ionization and Soft X-ray Emission from Coo…

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The X-ray luminosity and temperature of clusters and groups of galaxies do not scale in a self-similar manner. This has often been interpreted as a sign that the intracluster medium has been substantially heated by non-gravitational…

Astrophysics · Physics 2009-10-31 Greg L. Bryan

We present an analysis of X-ray colour maps of the cores of clusters of galaxies, formed from the ratios of counts in different X-ray bands. Our technique groups pixels lying between contours in an adaptively-smoothed image of a cluster. We…

Astrophysics · Physics 2008-11-26 J. S. Sanders , A. C. Fabian , S. W. Allen

In the disks of spiral galaxies, diffuse soft X-ray emission is known to be strongly correlated with star-forming regions. However, this emission is not simply from a thermal-equilibrium plasma and its origin remains greatly unclear. In…

Astrophysics of Galaxies · Physics 2022-12-22 Shuinai Zhang , Q. Daniel Wang , Wei Sun , Min Long , Jia Sun , Li Ji

We report results of an 18 ks exposure with the ACIS instrument on Chandra of the powerful z = 0.62 radio galaxy 3C 220.1. The X-ray emission separates into cluster gas of emission-weighted kT ~ 5 keV and 0.7-12 keV luminosity (to a radius…

Astrophysics · Physics 2009-11-06 D. M. Worrall , M. Birkinshaw , M. J. Hardcastle , C. R. Lawrence

Cool gas should be present in galaxy clusters due to stripping of galactic gas, infall onto the cluster, and from cooling flows. We searched for this gas through resonance absorption line observations from low-ionization metal line gas…

Astrophysics · Physics 2007-05-23 Eric D. Miller , Joel N. Bregman , Patricia M. Knezek

Excess soft X-ray emission in clusters of galaxies has so far been detected for sources that lie along lines-of-sight to very low Galactic HI column density (such as Coma, A1795, A2199 and Virgo, N_H 0.9-2.0 10^{20} cm-2). We show that the…

Astrophysics · Physics 2009-11-06 M. Bonamente , R. Lieu , J. Nevalainen , J. S. Kaastra

This is the first meeting specifically devoted to the topic of cluster soft excess and related phenomena. It calls together a group of some 40 scientists, mostly experts in the field, to present their findings on the observational aspects…

Astrophysics · Physics 2009-09-29 Richard Lieu , Jonathan Mittaz

There is a strong spatial correlation between brightest cluster galaxies (BCGs) and the peak density and cooling rate of the intra-cluster medium (ICM). In this paper we combine integral field spectroscopy, CO observations and X-ray data to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 S. L. Hamer , A. C. Edge , A. M. Swinbank , R. J. Wilman , H. R. Russell , A. C. Fabian , J. S. Sanders , P. Salom

Understanding the persistent emission is crucial for studying type I X-ray bursts, which provide insight into neutron star properties. Although accretion disc coronae appear to be common in many accreting systems, their fundamental…

High Energy Astrophysical Phenomena · Physics 2020-10-21 J. Speicher , D. R. Ballantyne , J. Malzac

Several deep PSPC observations of the Coma cluster reveal a very large-scale halo of soft X-ray emission, substantially in excess of the well known radiation from the hot intra-cluster medium. The excess emission, previously reported in the…

Astrophysics · Physics 2009-11-07 M. Bonamente , M. K. Joy , R. Lieu

A fraction of the thermal protons in the outer envelope of an X-ray cluster have velocities that exceed the local escape speed from the cluster gravitational potential. The Coulomb mean-free-path of these protons is larger than the virial…

Astrophysics · Physics 2010-10-27 Abraham Loeb

The virialization shock around an X-ray cluster primarily heats the ions, since they carry most of the kinetic energy of the infalling gas. Subsequently, the ions share their thermal energy with the electrons through Coulomb collisions. We…

Astrophysics · Physics 2009-10-30 David Fox , Abraham Loeb

The X-ray spectra of active galactic nuclei (AGNs) often exhibit an excess of emission above the primary power-law at energies <~ $2$ keV. Two models for the origin of this `soft excess' are ionized relativistic reflection from the inner…

High Energy Astrophysical Phenomena · Physics 2022-06-22 Xin Xiang , D. R. Ballantyne , S. Bianchi , A. De Rosa , G. Matt , R. Middei , P. -O. Petrucci , A. Rozanska , F. Ursini

As more cooling flow clusters of galaxies with central radio sources are observed with the Chandra and XMM-Newton X-ray Observatories, more examples of "bubbles" (low-emission regions in the X-ray coincident with radio emission) are being…

Astrophysics · Physics 2009-11-07 Noam Soker , Elizabeth L. Blanton , Craig L. Sarazin

Detailed temperature and abundance radial profile maps have revealed a significant lack of homogeneity within the Perseus Galaxy cluster. Previous surveys of Perseus with the Suzaku telescope, which has a worse angular resolution and less…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-05 Paul Geringer , Matthew Wampler-Doty , Melville Ulmer

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

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 crisis of the standard cooling flow model brought about by Chandra and XMM-Newton observations of galaxy clusters, has led to the development of several models which explore different heating processes in order to assess if they can…

Astrophysics · Physics 2009-11-10 Simona Ghizzardi , Silvano Molendi , Fabio Pizzolato , Sabrina de Grandi

We compute X-ray emission lines from thermal plasma in hot accretion flows. We show that line profiles are strong probes of the gas dynamics, and we present line-ratio diagnostics which are sensitive to the distribution of mass with…

Astrophysics · Physics 2009-10-31 Rosalba Perna , John Raymond , Ramesh Narayan

X-ray observations can be used to effectively probe the galactic ecosystem, particularly its hot and energetic components. However, existing X-ray studies of nearby star-forming galaxies are limited by insufficient data statistics and a…

High Energy Astrophysical Phenomena · Physics 2025-04-23 Luan Luan , Q. Daniel Wang