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Related papers: Observed Non-Steady State Cooling and the Moderate…

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The radial distributions of temperature, density, and gas entropy among cool-core clusters tend to be quite similar, suggesting that they have entered a quasi-steady state. If that state is regulated by a combination of thermal conduction…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 G. M. Voit

Cluster cooling flow models that include both thermal conduction and AGN heating have lower overall mass cooling rates and simultaneously sustain density and temperature profiles similar to those observed with no ad hoc mass dropout. To…

Astrophysics · Physics 2009-11-07 Fabrizio Brighenti , William G. Mathews

The gas temperature in the cores of many clusters of galaxies drops inward by about a factor of three or more within the central 100 kpc radius. The radiative cooling time drops over the same region from 5 or more Gyr down to below a few…

Astrophysics · Physics 2007-05-23 A. C. Fabian

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

We have calculated the emergent X-ray properties for models of cluster cooling flows including the effects of accumulated cooled material. The opacity of this cooled gas can reduce the overall X-ray luminosity of the cooling flow, and…

Astrophysics · Physics 2007-05-23 Michael W. Wise , Craig L. Sarazin

Recent results on cluster cooling flows are reviewed. Observations of excess soft X-ray provides the only direct evidence for a major repository for the cooled gas. Unfortunately, the frequency of occurrence of large excess columns is…

Astrophysics · Physics 2007-05-23 Craig L. Sarazin

We investigate temperature and entropy profiles of 13 nearby cooling flow clusters observed with the EPIC cameras of XMM-Newton. When normalized and scaled by the virial radius the temperature profiles turn out to be remarkably similar. At…

Astrophysics · Physics 2009-11-10 Rocco Piffaretti , Philippe Jetzer , Jelle Kaastra , Takayuki Tamura

The origin of the bimodality in cluster core entropy is still unknown. At the same time, recent work has shown that thermal conduction in clusters is likely a time-variable phenomenon. We consider if time-variable conduction and AGN…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Fulai Guo , S. Peng Oh

The radiative cooling time of the hot gas at the centres of cool cores in clusters of galaxies drops down to 10 million years and below. The observed mass cooling rate of such gas is very low, suggesting that AGN feedback is very tightly…

Astrophysics of Galaxies · Physics 2022-08-03 A. C. Fabian , G. J. Ferland , J. S. Sanders , B. R. McNamara , C. Pinto , S. A. Walker

We present an XMM-Newton observation of A1413, a hot (kT = 6.5 keV) galaxy cluster at z=0.143. We construct gas and temperature profiles up to ~1700 kpc, equivalent to ~0.7 r_200. The gas distribution is well described by a beta model in…

Astrophysics · Physics 2008-11-26 G. W. Pratt , M. Arnaud

The gas temperature in the cores of many clusters of galaxies drops inward by about a factor of three or more within the central 100kpc radius. The radiative cooling time drops over the same region from 5 or more Gyr down to about 10^8 yr.…

Astrophysics · Physics 2009-11-07 A. C. Fabian

Chandra has significantly advanced our knowledge of the processes in the intracluster gas. The discovery of remarkably regular ``cold fronts'', or contact discontinuities, in merging clusters showed that gas dynamic instabilities at the…

Astrophysics · Physics 2007-05-23 M. Markevitch , A. Vikhlinin , W. R. Forman

An XMM-Newton observation of the cool (kT=2.1 keV) cluster A1983, at z=0.044, is presented. Gas density and temperature profiles are calculated for the inner 500 h_{50}^{-1} kpc (~0.35 r_200). The outer regions of the surface brightness…

Astrophysics · Physics 2009-11-07 G. W. Pratt , M. Arnaud

(Abridged) We present observations of the cluster of galaxies associated with the X-ray source RX J0820.9+0752 and its dramatic central cluster galaxy (CCG) in the optical and X-ray wavebands.Unlike other cooling flow CCGs studied in…

Astrophysics · Physics 2009-11-07 C. M. Bayer-Kim , C. S. Crawford , S. W. Allen , A. C. Edge , A. C. Fabian

We study the feedback between heating and cooling of the intra-cluster medium (ICM) in cooling flow (CF) galaxies and clusters. We adopt the popular view that the heating is due to an active galactic nucleus (AGN), i.e. a central black hole…

Astrophysics · Physics 2009-11-10 Fabio Pizzolato , Noam Soker

We describe 2D gasdynamical models of jets that carry mass as well as energy to the hot gas in galaxy clusters. These flows have many attractive attributes for solving the galaxy cluster cooling flow problem: Why the hot gas temperature and…

Astrophysics · Physics 2009-11-11 Fabrizio Brighenti , William G. Mathews

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…

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

Using new XMM and Chandra observations we present an analysis of the temperature structure of the hot gas within a radius of 100 kpc of the bright nearby galaxy group NGC 5044. A spectral deprojection analysis of data extracted from…

Astrophysics · Physics 2009-11-07 David A. Buote , Aaron D. Lewis , Fabrizio Brighenti , William G. Mathews

The density profile of a cool core of intracluster gas is investigated for a cluster of galaxies that is initially in the virial equilibrium state, and then undergoes radiative cooling. The initial gas profile is derived under the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Naomi Ota , Kiyokazu Onzuka , Kuniaki Masai