Related papers: Prospects of High-Resolution X-ray Spectroscopy fo…
Whether caused by AGN jets, shocks, or mergers, the most definitive evidence for heating in cluster cores comes from X-ray spectroscopy. Unfortunately such spectra are essentially limited to studying the emission spectrum from the cluster…
Observations made during the last ten years with the Chandra X-ray Observatory have shed much light on the cooling gas in the centers of clusters of galaxies and the role of active galactic nucleus (AGN) heating. Cooling of the hot…
Chandra X-ray Observatory has revealed X-ray cavities in many nearby cooling flow clusters. The cavities trace feedback from the central active galactic nulceus (AGN) on the intracluster medium (ICM), an important ingredient in stabilizing…
High resolution X-ray spectroscopy of the hot gas in galaxy clusters has shown that the gas is not cooling to low temperatures at the predicted rates of hundreds to thousands of solar masses per year. X-ray images have revealed giant…
The current generation of flagship X-ray missions, Chandra and XMM-Newton, has changed our understanding of the so-called "cool core" galaxy clusters and groups. Instead of the initial idea that the thermal gas is cooling and flowing toward…
Detection of the copious amount of X-ray emission from the dilute hot plasma in galaxy clusters suggests that a substantial fraction of the central intracluster medium (ICM) is cooling radiatively on a time scale much faster than the Hubble…
The lack of very cool gas at the cores of groups and clusters of galaxies, even where the cooling time is significantly shorter than the Hubble time, has been interpreted as evidence of sources that re-heat the intergalactic medium. Most…
This contribution illustrates the study of galaxy clusters as astrophysical laboratories as well as probes for the large-scale structure of the Universe. Using the REFLEX Cluster Survey, the measurement of the statistics of the large-scale…
We investigate a series of steady-state models of galaxy clusters, in which the hot intracluster gas is efficiently heated by active galactic nucleus (AGN) feedback and thermal conduction, and in which the mass accretion rates are highly…
The hot plasma filling galaxy clusters emits copious X-ray radiation. The classic unheated and unperturbed cooling flow model predicts dramatic cooling rates and an isobaric X-ray spectrum with constant differential luminosity distribution.…
New X-ray observations with XMM-Newton show a lack of spectral evidence for large amounts of cooling and condensing gas in the centers of galaxy clusters believed to harbour strong cooling flows. The paper reexplores the cooling flow…
Unopposed radiative cooling of plasma would lead to the cooling catastrophe, a massive inflow of condensing gas, manifest in the core of galaxies, groups and clusters. The last generation X-ray telescopes, Chandra and XMM, have radically…
While rich clusters are powerful sources of X-rays, gamma-ray emission from these large cosmic structures has not been detected yet. X-ray radiative energy losses in the central regions of relaxed galaxy clusters are so strong that one…
Recent observations show that the cooling flows in the central regions of galaxy clusters are highly suppressed. Observed AGN-induced cavities/bubbles are a leading candidate for suppressing cooling, usually via some form of mechanical…
X-ray cavities are key tracers of mechanical (or radio mode) heating arising from the active galactic nuclei (AGN) in brightest cluster galaxies. We report on a survey for X-ray cavities in 83 massive, high-redshift (0.4<z<1.2) clusters of…
We investigate a series of steady-state models of galaxy clusters, in which the hot intracluster gas is efficiently heated by active galactic nucleus (AGN) feedback and thermal conduction, and in which the mass accretion rates are highly…
X-ray spectra of galaxy clusters are dominated by the thermal emission from the hot intracluster medium. In some cases, besides the thermal component, spectral models require additional components associated, e.g., with resonant scattering…
Shock fronts driven by active galactic nuclei in galaxy cluster cores represent a promising mechanism to heat the intracluster gas by converting kinetic energy into thermal energy through gas compression, thereby offsetting radiative…
The co-evolution between supermassive black holes and their environment is most directly traced by the hot atmospheres of dark matter halos. Cooling of the hot atmosphere supplies the central regions with fresh gas, igniting active galactic…
Strong AGN heating provides an alternative means for the disruption of cluster cool cores (CCs) to cluster mergers. In this work we present a systematic Chandra study of a sample of 108 nearby ($z<0.1$) galaxy clusters, to investigate the…