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相关论文: Why Do Only Some Galaxy Clusters Have Cool Cores?

200 篇论文

The influence of cool galaxy cluster cores on the X-ray luminosity--gravitational mass relation is studied with Chandra observations of 64 clusters in the HIFLUGCS sample. As preliminary results we find (i) a significant offset of cool core…

天体物理学 · 物理学 2015-06-24 Thomas H. Reiprich , Daniel S. Hudson

We present detailed comparisons of the intracluster medium (ICM) in cosmological Eulerian cluster simulations with deep Chandra observations of nearby relaxed clusters. To assess the impact of galaxy formation, we compare two sets of…

天体物理学 · 物理学 2011-02-11 Daisuke Nagai , Andrey V. Kravtsov , Alexey Vikhlinin

In this study, we examine the frequency and physical drivers of transformations from cool-core (CC) to non-cool-core (NCC) clusters, and vice versa, in a sample of 352 massive galaxy clusters (M_vir = 10^14-15.3 M_sun) from the TNG-Cluster…

星系天体物理 · 物理学 2025-10-01 Katrin Lehle , Dylan Nelson , Annalisa Pillepich

Two-body relaxation times of nuclear star clusters are short enough that gravitational encounters should substantially affect their structure in 10 Gyr or less. In nuclear star clusters without massive black holes, dynamical evolution is a…

天体物理学 · 物理学 2011-02-11 David Merritt

The formation and evolution of an X--ray cluster is studied using a 3--D N-body + hydrodynamical simulation which includes feedback of energy and iron from cluster galaxies. The differences in evolution and final state between the…

天体物理学 · 物理学 2008-11-26 Christopher A. Metzler , August E. Evrard

A study of the structural and scaling properties of the temperature distribution of the hot, X-ray emitting intra-cluster medium of galaxy clusters, and its dependence on dynamical state, can give insights into the physical processes…

天体物理学 · 物理学 2009-11-11 G. W. Pratt , H. Boehringer , J. H. Croston , M. Arnaud , S. Borgani , A. Finoguenov , R. F. Temple

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…

宇宙学与河外天体物理 · 物理学 2015-05-14 A. C. Fabian , J. S. Sanders

(Abridged) To define a framework for the formation and evolution of the cooling cores in X-ray galaxy clusters, we study how the physical properties change as function of the cosmic time in the inner regions of a 4 keV and 8 keV galaxy…

天体物理学 · 物理学 2009-11-13 Stefano Ettori , Fabrizio Brighenti

We investigate the detection of Cool Cores (CCs) in the distant galaxy cluster population, with the purpose of measuring the CC fraction out to redshift 0.7 < z < 1.4. Using a sample of nearby clusters spanning a wide range of morphologies,…

天体物理学 · 物理学 2009-11-13 Joana S. Santos , Piero Rosati , Paolo Tozzi , Hans Boehringer , Stefano Ettori , Andrea Bignamini

I review cosmological simulations of X-ray clusters. Simulations have increased in resolution dramatically and the effects of radiative cooling, star formation feedback, and chemical enrichment on the ICM are being simulated. The structure…

天体物理学 · 物理学 2007-05-23 Michael L. Norman

Theoretical studies of the physical processes guiding the formation and evolution of galaxies and galaxy clusters in the X-ray are mainly based on the results of numerical hydrodynamical N-body simulations, which in turn are often directly…

天体物理学 · 物理学 2015-06-24 P. Mazzotta , E. Rasia , L. Moscardini , G. Tormen

Evolutions of X-ray clusters of galaxies are studied by N-body (shell model) + mesh code (TVD) simulations on the assumption of spherical symmetry. We consider a density perturbation of $10^{15} M_{\odot}$ composed of dark matter and gas in…

天体物理学 · 物理学 2009-10-30 Motokazu Takizawa , Shin Mineshige

With rapid improvements in the assembly of large samples of galaxy clusters, we are approaching the ability to study clusters at $z\gtrsim2$. Evolutionary studies comparing these distant clusters to the clusters in our local universe depend…

Chandra X-ray observations revealed the presence of cold fronts (sharp contact discontinuities between gas regions with different temperatures and densities) in the centers of many, if not most, relaxed clusters with cool cores. We use…

天体物理学 · 物理学 2008-11-26 Yago Ascasibar , Maxim Markevitch

We compute, including a current state-of-the-art treatment of hydrodynamical processes, heating and cooling, a variety of cosmological models into the extreme nonlinear phase to enable comparisons with observations. First, we note the…

天体物理学 · 物理学 2009-10-28 Jeremiah P. Ostriker , Renyue Cen

Unopposed radiative cooling in clusters of galaxies results in excessive mass deposition rates. However, the cool cores of galaxy clusters are continuously heated by thermal conduction and turbulent heat diffusion due to minor mergers or…

宇宙学与河外天体物理 · 物理学 2015-05-19 M. Ruszkowski , S. Peng Oh

X-ray selected samples are known to miss galaxy clusters that are gas poor and have a low surface brightness. This is different for the optically selected samples such as the X-ray Unbiased Selected Sample (XUCS). We characterise the origin…

宇宙学与河外天体物理 · 物理学 2022-10-05 Antonio Ragagnin , Stefano Andreon , Emanuella Puddu

We use N-body simulations to study evolution of galaxy clusters over the redshift interval 0 <= z <= 0.5 in cosmological models with a mixture of cold and hot dark matter (CHDM). Four different techniques are utilized: the cluster-cluster…

天体物理学 · 物理学 2009-10-28 Charles Walter , Anatoly Klypin

We present a detailed Chandra study of a sample of ten clusters of galaxies selected based on the presence of substructures in their optical images. The X-ray surface brightness maps of most of these clusters show anisotropic morphologies,…

星系天体物理 · 物理学 2014-05-16 Kiran Lakhchaura , K. P. Singh

Galaxy clusters are important probes for both cosmology and galaxy formation physics. We test the cosmological, hydrodynamical FLAMINGO simulations by comparing to observations of the gaseous properties of clusters measured from X-ray…