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Related papers: An Evolving Entropy Floor in the Intracluster Gas?

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Studies of the X-ray surface brightness profiles of clusters, coupled with theoretical considerations, suggest that the breaking of self-similarity in the hot gas results from an `entropy floor', established by some heating process, which…

Astrophysics · Physics 2009-10-31 E. J. Lloyd-Davies , T. J. Ponman , D. B. Cannon

Galaxy clusters are the most recent products of hierarchical accretion over cosmological scales. The gas accreted from the cosmic field is thermalized inside the cluster halo. Gas entropy and pressure are expected to have a self-similar…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-23 V. Ghirardini , S. Ettori , S. Amodeo , R. Capasso , M. Sereno

We perform a set of non--radiative cosmological simulations of a preheated intracluster medium in which the entropy of the gas was uniformly boosted at high redshift. The results of these simulations are used first to test the current…

Astrophysics · Physics 2009-06-23 Joshua D. Younger , Greg L. Bryan

[Abridged] The entropy distribution of the intracluster gas reflects both accretion history of the gas and processes of feedback which provide a further non-gravitational energy besides the potential one. In this work, we study the profiles…

Astrophysics · Physics 2009-11-13 A. Morandi , S. Ettori

(Abridged) We revisit the scaling relationships between the dark matter mass and observed X-ray luminosity and temperature of galaxy clusters and groups in the local Universe. Specifically, we compare recent observations with analytic…

Recent observations of entropy of intracluster medium (ICM) at high redshift are not consistent with a redshift independent entropy floor. In order to interpret these observations, we study models in which the entropy of ICM is enhanced at…

Astrophysics · Physics 2009-11-10 Biman B. Nath

Both preheating of the intergalactic medium and radiative cooling of low entropy gas have been proposed to explain the deviation from self-similarity in the cluster L_x-T_x relation and the observed entropy floor in these systems. However,…

Astrophysics · Physics 2009-11-07 S. Peng Oh , Andrew Benson

We examine profiles and scaling properties of the entropy of the intergalactic gas in a sample of 66 virialized systems, ranging in mass from single elliptical galaxies to rich clusters, for which we have resolved X-ray temperature…

Astrophysics · Physics 2009-09-29 T. J. Ponman , A. J. R. Sanderson , A. Finoguenov

Observations of the evolution of the galaxy cluster X-ray luminosity function suggest that the entropy of the intra-cluster medium plays a significant role in determining the development of cluster X-ray properties. I present a theoretical…

Astrophysics · Physics 2015-06-24 Richard G Bower

We present a set of cluster models that link the present-day properties of clusters to the processes that govern galaxy formation. These models treat the entropy distribution of the intracluster medium as its most fundamental property.…

Astrophysics · Physics 2009-11-07 G. Mark Voit , Greg L. Bryan , Michael L. Balogh , Richard G. Bower

The X-ray properties of a sample of 11 high-redshift (0.6<z<1.0) clusters observed with Chandra and/or XMM are used to investigate the evolution of the cluster scaling relations. The observed evolution of the L-T and M-L relations is…

Astrophysics · Physics 2009-11-10 B. J. Maughan , L. R. Jones , H. Ebeling , C. Scharf

Using XMM-Newton observations, we investigate the scaling and structural properties of the ICM entropy in a sample of 10 nearby (z < 0.2) relaxed galaxy clusters in the temperature range 2-9 keV. We derive the local entropy-temperature…

Astrophysics · Physics 2009-11-13 G. W. Pratt , M. Arnaud , E. Pointecouteau

The X-ray properties of a relaxed cluster of galaxies are determined primarily by its gravitational potential well and the entropy distribution of its intracluster gas. That entropy distribution reflects both the accretion history of the…

Astrophysics · Physics 2009-11-13 Megan Donahue , Donald J. Horner , Kenneth W. Cavagnolo , G. Mark Voit

Studies of cluster X-ray scaling relations have led to suggestions that non-gravitational processes, e.g., radiative cooling and/or "preheating", have significantly modified the entropy of the intracluster medium (ICM). For the first time,…

Astrophysics · Physics 2009-11-07 Ian G. McCarthy , Gilbert P. Holder , Arif Babul , Michael L. Balogh

We use hydrodynamical simulations of galaxy clusters and groups to study the effect of pre-heating on the entropy structure of the ICM. Our simulations account for non-gravitational heating of the gas either by imposing a minimum entropy…

Astrophysics · Physics 2009-11-11 S. Borgani , A. Finoguenov , S. T. Kay , T. J. Ponman , V. Springel , P. Tozzi , G. M. Voit

We measure the evolution of the X-ray luminosity-temperature (L_X-T) relation since z~1.5 using a sample of 211 serendipitously detected galaxy clusters with spectroscopic redshifts drawn from the XMM Cluster Survey first data release…

The failure of purely gravitational models of X-ray cluster formation to reproduce basic observed properties of the local cluster population suggests the need for one or more additional physical processes operating on the intracluster…

Astrophysics · Physics 2009-10-31 John J. Bialek , August E. Evrard , Joseph J. Mohr

(Abridged) We examine the radial entropy distribution and its scaling using 31 nearby galaxy clusters from the Representative XMM-Newton Cluster Structure Survey (REXCESS). The entropy profiles are robustly measured at least out to R_1000…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-22 G. W. Pratt , M. Arnaud , R. Piffaretti , H. Boehringer , T. J. Ponman , J. H. Croston , G. M. Voit , S. Borgani , R. G. Bower

X-ray observations of an "entropy floor" in nearby groups and clusters of galaxies offer evidence that important non-gravitational processes, such as radiative cooling and/or "preheating", have strongly influenced the evolution of the…

Astrophysics · Physics 2009-11-07 Ian G. McCarthy , Arif Babul , Gilbert P. Holder , Michael L. Balogh
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