[Previous] | [Session 2] | [Next]

[2.05] Cluster Scale AGN Shock Outbursts in Hydra A and MS0735.6+7421

P. E. J. Nulsen (Harvard-Smithsonian Center for Astrophysics), B. R. McNamara (Ohio University), M. W. Wise (MIT Center for Space Research), L. P. David (Harvard-Smithsonian Center for Astrophysics)

Deep Chandra images have revealed weak shock fronts in the intracluster medium produced by an outburst from a central AGN in several clusters. The two largest shock fronts found so far, in Hydra A and MS0735.6+7421, encompass regions ~300 kpc in radius and closely surround the large radio lobes that drive them. A spherical hydrodynamic model gives estimates for the Mach number of the (aspherical) shock front in Hydra A in the range 1.2 to 1.4, and ranging from 1.4 to 1.6 in MS0735.6+7421. The ages of the outbursts are 136 My and 104 My, and their total energies are ~ 10⁶¹ and ~6 \times 10⁶¹ erg, respectively. The mean mechanical powers of the outbursts that drove these shocks lie in the range of quasar luminosities. The shocks are significant for the energetics of cooling flows and for preheating of whole clusters. The shock flows reveal the history of the AGN outbursts. This work was partly supported by NASA grants NAS8-01130 and NAS8-03060.

[Previous] | [Session 2] | [Next]

Bulletin of the American Astronomical Society, 36 #3
© 2004. The American Astronomical Soceity.