相关论文: Stopping Cooling Flows with Jets

We have studied the effects of Compton cooling on cooling flow by performing numerical hydrodynamic calculations of the time evolution of hot gas in clusters of galaxies with luminous quasars. We assumed various temperatures for the hot…

Chandra images of galaxy clusters have revealed a wealth of structure unseen by previous generations of low resolution X-ray observatories. In the cores of clusters, bright, irregular X-ray emission is now routinely seen within central…

We propose that the outer portions of cooling flows (CFs) in clusters of galaxies are frequently disrupted by radio jets, and that their effective ages are much shorter than the cluster ages. The inner regions, where the gas density is…

We present the results of high-resolution AP3M+SPH simulations of merging clusters of galaxies. We find that the compression and shocking of the core gas during a merger can lead to large increases in bolometric X-ray luminosities and…

Star formation in the universe's largest galaxies---the ones at the centers of galaxy clusters---depends critically on the thermodynamic state of their hot gaseous atmospheres. Central galaxies with low-entropy, high-density atmospheres…

With their relatively fast variability time-scales, Galactic X-ray binaries provide an excellent laboratory to explore the physics of accretion and related phenomena, most notably outflows, over different regimes. After comparing the…

One of the key physical processes that helps prevent strong cooling flows in galaxy clusters is the continued energy input from the central active galactic nucleus (AGN) of the cluster. However, it remains unclear how this energy is…

We present the first implementation of Active Galactic Nuclei (AGN) feedback in the form of momentum driven jets in an Adaptive Mesh Refinement (AMR) cosmological resimulation of a galaxy cluster. The jets are powered by gas accretion onto…

Shortly after the first results of Chandra and XMM-Newton appeared, many researchers in the field abandoned the term "cooling flow clusters" in favor of the name "cool core clusters". This change, I argue, has been causing damage by…

Recent observations of the interactions between radio sources and the X-ray-emitting gas in cooling flows in the cores of clusters of galaxies are reviewed. The radio sources inflate bubbles in the X-ray gas, which then rise buoyantly…

It is thought that many characteristics of the gaseous features within the central parsec of our Galaxy, are associated with the accretion of ambient plasma by a central concentration of mass. Using a 3D hydrodynamical code, we have been…

For two decades the steady-state cooling-flow model has dominated the literature of cluster and elliptical-galaxy X-ray sources. For ten years this model has been in severe difficulty from a theoretical point of view, and it is now coming…

X-Ray observations of groups and clusters of galaxies show that the Intra-Cluster Medium (ICM) in their cores is hotter than expected from cosmological numerical simulations of cluster formation which include star formation, radiative…

We consider a situation in which a brightest cluster galaxy (BCG) moves in ambient hot gas in the central region of a cool core cluster of galaxies, following the study by Inoue (2014, PASJ, 66, 60). In the rest frame of the BCG, the hot…

Without additional heating, radiative cooling of gas in the halos of massive galaxies (Milky Way and above) produces cold gas or stars in excess of that observed. Previous work suggested that AGN jets are likely required, but the form of…

It is now clear that AGN heat cooling flows, largely by driving winds. The winds may contain a relativistic component that generates powerful synchrotron radiation, but it is not clear that all winds do so. The spatial and temporal…

Multi-wavelength observations indicate that the intracluster medium in some galaxy clusters contains cold filaments, while their formation mechanism remains debated. Using hydrodynamic simulations, we show that cold filaments could…

Cosmological simulations, as well as mounting evidence from observations, have shown that supermassive black holes play a fundamental role in regulating the formation of stars throughout cosmic time. This has been clearly demonstrated in…

We present a detailed analysis of the thermal X-ray emission from the intracluster medium (ICM) in the cool-core galaxy cluster Abell 2667 ($z=0.23$). Our goal is to detect low-temperature ($<2$ keV) X-ray emitting gas, potentially…

The X-ray spectra of black hole binaries in the low/hard state first harden as the flux decreases, then soften. This change in behaviour has been variously attributed to either the X-rays switching from being produced in the flow to being…