English
Related papers

Related papers: Testing an entropy estimator related to the dynami…

200 papers

Non-gravitational processes, such as feedback from galaxies and their active nuclei, are believed to have injected excess entropy into the intracluster gas, and therefore to have modified the density profiles in galaxy clusters during their…

Astrophysics · Physics 2009-11-13 Wenjuan Fang , Zoltan Haiman

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 show how hydrostatic equilibrium in galaxy clusters can be quantitatively probed combining X-ray, SZ, and gravitational-lensing data. Our previously published method for recovering three-dimensional cluster gas distributions avoids the…

Astrophysics · Physics 2009-11-13 Ewald Puchwein , Matthias Bartelmann

Increasing inhomogeneity due to gravitational clumping reflects increasing gravitational entropy in a time evolving universe. Starting from an ensemble of uniformly distributed particles it is demonstrated that gravitational clustering is…

Astrophysics · Physics 2007-05-23 Manfred P. Leubner

Evidence is presented for a recent evolution of the relaxation processes in clusters of galaxies, using large optical and X-ray cluster samples. The criteria of the cluster relaxation used are the cluster ellipticity, the ICM temperature…

Astrophysics · Physics 2009-11-07 Manolis Plionis

We analyze with hydrodynamical simulations the evolution of galaxy clusters in a cosmological environment. Power ratios (Buote \& Tsai 1995) are used to quantitatively relate cluster morphologies to their dynamical states. The simulated…

Astrophysics · Physics 2015-06-24 John C. Tsai , David A. Buote

We consider a sample of 51 distant galaxy clusters at 0.15<z<0.9 (<z> about 0.3), each cluster having at least 10 galaxies with available redshift in the literature. We select member galaxies, analyze the velocity dispersion profiles, and…

Astrophysics · Physics 2009-10-31 M. Girardi , M. Mezzetti

The temperature and density of the hot diffuse medium pervading galaxy groups and clusters combine into one significant quantity, the entropy. Here we express the entropy levels and profiles in model-independent forms by joining two…

Astrophysics · Physics 2009-11-13 A. Cavaliere , A. Lapi , Y. Rephaeli

Recently, Suzaku has produced temperature and entropy profiles, along with profiles of gas density, gas fraction, and mass, for multiple galaxy clusters out to ~r_200 (~= virial radius). In this paper, we compare these novel X-ray…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Jack O. Burns , Samuel W. Skillman , Brian W. O'Shea

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

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 rate of galaxy cluster eccentricity evolution is useful in understanding large scale structure. Rapid evolution for $z < $ 0.13 has been found in two different observed cluster samples. We present an analysis of projections of 41…

Astrophysics · Physics 2009-11-10 Stephen Floor , Adrian Melott , and Patrick Motl

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 consider a sample of about 50 distant galaxy clusters at z>0.15 (<z> about 0.3), each cluster having at least 10 galaxies with available redshift in the literature. We select member galaxies, analyze the velocity dispersion profiles, and…

Astrophysics · Physics 2007-05-23 M. Girardi , M. Mezzetti , A. Devetak

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

In this paper, we have extended the entropy-driven model of cluster evolution developed by Bower (1997) in order to be able to predict the evolution of galaxy clusters for a range of cosmological scenarios. We have applied this model to…

Astrophysics · Physics 2009-10-30 Scott T. Kay , Richard G. Bower

We use Enzo, a hybrid Eulerian AMR/N-body code including non-gravitational heating and cooling, to explore the morphology of the X-ray gas in clusters of galaxies and its evolution in current generation cosmological simulations. We employ…

Astrophysics · Physics 2010-11-11 Tesla E. Jeltema , Eric J. Hallman , Jack O. Burns , Patrick M. Motl

Galaxy clusters are excellent probes to study the effect of environment on galaxy formation and evolution. Along with high-quality observational data, accurate cosmological simulations are required to improve our understanding of galaxy…

Astrophysics of Galaxies · Physics 2021-09-15 Syeda Lammim Ahad , Yannick M. Bahé , Henk Hoekstra , Remco F. J. van der Burg , Adam Muzzin

We study the X-ray cluster gas density distribution in hydrostatic equilibrium using the universal temperature profile obtained from recent simulations involving only gravitational processes. If this temperature profile is an indicator of…

Astrophysics · Physics 2009-11-10 Suparna Roychowdhury , Biman B. Nath

We present hydrodynamical N-body simulations of clusters of galaxies with feedback taken from semi-analytic models of galaxy formation. The advantage of this technique is that the source of feedback in our simulations is a population of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 C. J. Short , P. A. Thomas
‹ Prev 1 2 3 10 Next ›