Previous | Session 146 | Next
A. Gardini (Dept. of Astronomy - UIUC), P. M. Ricker (Dept. of Astronomy - UIUC --- NCSA)
Recent X-ray observations of cluster of galaxies performed by the Chandra telescope show in some cases the presence of depressions in the intracluster medium (ICM) often coincident with regions of radio emission. It is straightforward to identify them as cavities devoided of material by the hot plasma deposed in the ICM by the powerful central AGN. It is then easy to show that after the plasma reached pressure equilibrium with the environment, it has to rise in the cluster atmosphere by buoyancy.
We developed hydrodynamic numerical simulations to explore the evolution of the plasma cavities in the phase of buoyancy and to study how it affects the general properties of the ICM. In particular, we consider their effects on the development of a cooling flow in the cluster medium.
We performed a set of simulations using the adaptive mesh refinement code FLASH. Each simulation reproduces a cluster similar to A2390 with a pair of bubbles filled by relativistic plasma; the bubble radius and their distance from the center vary in each simulation. It is shown how the ICM is affected by the presence of bubbles according to these parameters, and in particular how much the cooling flow is retarded.
A comparison with real Chandra data can also be performed applying the XMAS tool to simulations.
The authors acknowledge support under a Presidential Early Career Award from the U.S. Department of Energy, Lawrence Livermore National Laboratory (contract B532720) as well as the National Center for Supercomputing Applications.
Previous | Session 146 | Next
Bulletin of the American Astronomical Society, 36 5
© 2004. The American Astronomical Society.