Impact of tangled magnetic fields on AGNblown bubbles.pdfVIP

A Mon. Not. R. Astron. Soc. 000, 1–12 (2006) Printed 3 February 2008 (MN L T X style file v2.2) E Impact of tangled magnetic fields on AGN-blown bubbles 1⋆ 1 2 3 4 M. Ruszkowski, T.A. Enßlin , M. Br¨uggen , S. Heinz , C. Pfrommer 1Max Planck Institute for Astrophysics, Karl-Schwarzschild-Str. 1, 85741 Garching, Germany 7 2International University Bremen, Campus Ring 1, Bremen, Germany 0 3Department of Astronomy, University of Wisconsin, 475 N Charter Street Madison, WI 53706, USA 0 4 Canadian Institute for Theoretical Astrophysics, 60 St. George Street Toronto, Ontario, M5S 3H8, Canada 2 r a Submitted 2006 December M 0 ABSTRACT 3 There is growing consensus that feedback from active galactic nuclei (AGN) is the main mechanism responsible for stopping cooling flows in clusters of galaxies. AGN 1 are known to inflate buoyant bubbles that supply mechanical power to the intracluster v gas (ICM). High Reynolds number hydrodynamical simulations show that such bub- 1 bles get entirely disrupted within 100 Myr, as they rise in cluster atmospheres, which 0 is contrary to observations. This artificial mixing has consequences for models trying 8 3 to quantify the amount of heating and star formation in cool core clusters of galaxies. 0