MHD Simulations of the Formation of Cold Fronts
Abstract
Chandra observations revealed detailed structures of hot plasmas confined in subclusters moving in cluster of galaxies. For example A3667 showed sharp X-ray brightness edge around the moving subcluster. This front called the cold front (Vikhlinin et al. 2001) suggests that heat conduction across the front is suppressed. We carried out 2D and 3D magnetohydrodynamic (MHD) simulations to study the interaction between the X-ray emitting plasmas in moving subclusters and the surrounding intergalactic matter. We assumed the existence of large-scale magnetic fields in clusters of galaxies and included the effects of non-isotropic heat conduction depending on the direction of magnetic field lines. Numerical results indicate that Kelvin Helmholtz instability at the interface between the subcluster plasma and intergalactic plasma is suppressed partly due to the magnetic fields parallel to the interface. Unless magnetic field is very weak we successfully reproduced the X-ray brightness distributions around the cold front. We also discuss possible plasmoid ejections and plasma heating due to magnetic reconnections taking place in the magnetotail of the subcluster
- Publication:
-
IAU Joint Discussion
- Pub Date:
- 2003
- Bibcode:
- 2003IAUJD..10E..29A