Related papers: Simple models of cooling flows
We investigate the properties of the intracluster medium (ICM) that forms within N-body/hydrodynamical simulations of galaxy clusters in a \LambdaCDM cosmology. When radiative cooling and a simple model for galactic feedback are included,…
A simple assumption of an emergence in gas of small atomic clusters consisting of $c$ particles each, leads to a phase separation (first order transition). It reveals itself by an emergence of ``forbidden'' density range starting at a…
Our Chandra X-ray Observatory archival study of intracluster entropy in a sample of 222 galaxy clusters shows that H-alpha and radio emission from the brightest cluster galaxy are much more pronounced when the cluster's core gas entropy is…
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…
(abridged) Uninhibited radiative cooling in clusters of galaxies would lead to excessive mass accretion rates contrary to observations. One of the key proposals to offset radiative energy losses is thermal conduction from outer, hotter…
Radiative cooling may plausibly cause hot gas in the centre of a massive galaxy, or galaxy cluster, to become gravitationally unstable. The subsequent collapse of this gas on a dynamical timescale can provide an abundant source of fuel for…
In galaxy clusters the entropy distribution of the IntraCluster Plasma modulates the latter's equilibrium within the Dark Matter gravitational wells, as rendered by our Supermodel. We argue the entropy production at the boundary shocks to…
We investigate the form and evolution of the X-ray luminosity-temperature (LT) relation of a sample of 114 galaxy clusters observed with Chandra at 0.1<z<1.3. The clusters were divided into subsamples based on their X-ray morphology or…
We present Chandra data from a 31.7 ks observation of the Centaurus cluster, using the ACIS-S detector. Images of the X-ray emission show a plume-like feature at the centre of the cluster, of extent 60 arcsec (20 kpc in projection). The…
Ultracold plasmas are a promising candidate for the creation of strongly-coupled Coulomb systems. Unfortunately, the values of the coupling parameter Gamma_e actually achieved after photoionization of the neutral atoms remain relatively…
We simulate the effects of viscous dissipation of waves that are generated by AGN activity in clusters of galaxies. We demonstrate that the amount of viscous heating associated with the dissipation of these waves can offset radiative…
We employ hydrodynamic equations to follow the clustering instability of a freely cooling dilute gas of inelastically colliding spheres into a well-developed nonlinear regime. We simplify the problem by dealing with a one-dimensional…
We present the first results of our study of a sample of 101 X-ray galaxy groups and clusters, which is volume-limited in each of three X-ray luminosity bins. The aim of this work is to study the properties of the innermost ICM in the cores…
Aims. We aim to provide constraints on evolutionary scenarios in clusters. One of our main goals is to understand whether, as claimed by some, the cool core/non-cool core division is established once and for all during the early history of…
Numerical simulations of active galactic nuclei (AGN) feedback in cool-core galaxy clusters have successfully avoided classical cooling flows, but often produce too much cold gas. We perform adaptive mesh simulations that include…
ASCA data are used to obtain two-dimensional gas temperature maps of A2256, A2319, A2163 and A665. In all four, the temperature decreases significantly at off-center distances of ~1 h^{-1} Mpc. Central regions of the two nearer clusters…
Expanding X-ray cavities observed in hot gas atmospheres of many galaxy groups and clusters generate shock waves and turbulence that are primary heating mechanisms required to avoid uninhibited radiatively cooling flows which are not…
Extended warm and cold gas nebulae, with complex morphologies and kinematics, have been observed in the centres of cool-core galaxy clusters. Their origin within the hot intracluster medium (ICM) is still puzzling, and among many…
I use a simple analytical model to show that simple heat conduction models cannot significantly suppress cluster cooling flows. I build a static medium where heat conduction globally balances radiative cooling, and then perturb it. I show…
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…