相关论文: Three-dimensional Magnetohydrodynamic Simulations …
Recent high resolution observations by the {\it Chandra} X-ray satellite revealed various substructures in hot X-ray emitting plasmas in cluster of galaxies. For example, {\it Chandra} revealed the existence of sharp discontinuities in the…
Recent Chandra observations of clusters of galaxies revealed the existence of a sharp ridge in the X-ray surface brightness where the temperature drops across the front. This front is called the cold front. We present the results of…
This conference presentation discusses a Chandra observation of the cold front in Abell 3667. We first review our earlier results which include a measurement of the front velocity, M~1, using the ratio of exterior and interior gas…
We perform three dimensional hydrodynamical simulations of a moving substructure in a cluster of galaxies. We investigate dynamical evolution of the intracluster medium (ICM) in and around the substructure moving radially in the larger…
We use the Chandra observation of the cold front in the intracluster gas of A3667 to estimate the magnetic field strength near the front. The front is seen in the Chandra data as a sharp discontinuity in the gas density which delineates a…
Recently, high-resolution Chandra observations revealed the existence of very sharp features in the X-ray surface brightness and temperature maps of several clusters (Vikhlinin et. al., 2001). These features, called ``cold fronts'', are…
We use adaptive-mesh magnetohydrodynamic simulations to study the effect of magnetic fields on ram pressure stripping of galaxies in the intracluster medium (ICM). Although the magnetic pressure in typical clusters is not strong enough to…
The intracluster medium (ICM) is stably stratified in the hydrodynamic sense with the entropy $s$ increasing outwards. However, thermal conduction along magnetic field lines fundamentally changes the stability of the ICM, leading to the…
A fully three-dimensional (3D) magnetohydrodynamical (MHD) model is applied to simulate the evolution of the large-scale magnetic field in cluster galaxies interacting with the intra-cluster medium (ICM). As the model input we use a time…
We present the results of a very deep (500 ks) Chandra observation, along with tailored numerical simulations, of the nearest, best resolved cluster cold front in the sky, which lies 90 kpc (19 arcmin) to the north-west of M 87. The…
The role played by magnetic fields in the intracluster medium (ICM) of galaxy clusters is complex. The weakly collisional nature of the ICM leads to thermal conduction that is channelled along field lines. This anisotropic heat conduction…
In the outskirts of the intracluster medium (ICM) in galaxy clusters, the temperature decreases with radius. Due to the weakly collisional nature of the plasma, these regions are susceptible to the magneto-thermal instability (MTI), which…
The most massive baryonic component of galaxy clusters is the "intracluster medium" (ICM), a diffuse, hot, weakly magnetized plasma that is most easily observed in the X-ray band. Despite being observed for decades, the macroscopic…
Cluster media are dynamical, not static; observational evidence suggests they are turbulent. High-resolution simulations of the intracluster media (ICMs) and of idealized, similar media help us understand the complex physics and…
During structure formation, energetic events and random motions of the hot gas residing inside galaxy clusters (the intracluster medium, ICM) generate turbulent motions. Radio diffuse emission probes the presence of magnetic fields and…
In the intracluster medium (ICM) of galaxies, exchanges of heat across magnetic field lines are strongly suppressed. This anisotropic heat conduction, in the presence of a large-scale temperature gradient, destabilizes the outskirts of…
Galaxy clusters host a large reservoir of diffuse plasma with radially-varying temperature profiles. The efficiency of thermal conduction in the intracluster medium (ICM) is complicated by the existence of turbulence and magnetic fields,…
X-ray observations of hot gas in galaxy clusters often show steeper temperature gradients across cold fronts -- contact discontinuities, driven by the differential gas motions. These sharp (a few kpc wide) surface brightness/temperature…
(Abridged) Cold fronts in cluster cool cores should be erased on short timescales by thermal conduction, unless protected by magnetic fields that are "draped" parallel to the front surfaces, suppressing conduction perpendicular to the…
We present results from the combination of two Chandra pointings of the central region of the cluster of galaxies A3667. From the data analysis of the first pointing Vikhlinin et al. reported the discovery of a prominent cold front which is…