NOAO >   Observing Info >   Approved Programs >   2005A-0435

Small NOAO Logo

Proposal Information for 2005A-0435


PI: David Rafferty, Ohio University, rafferty@helios.phy.ohiou.edu
Address: Astrophysical Institute / Department of Physics and Astronomy, Clippinger Labs, Athens, OH 45701, USA

CoI: Brian McNamara, Ohio University
CoI: Paul Nulsen, Harvard Smithsonian Center for Astrophysics
CoI: Mike Wise, MIT Center for Space Research

Title: Supergiant X-ray Cavities and AGN Feedback in a Distant Galaxy Cluster

Abstract: The redshift z=0.22 galaxy cluster MS0735.6+7421 is experiencing the largest and most powerful interaction known between a radio source and the intracluster medium (ICM). The radio jets emerging from the cD galaxy's active nucleus (AGN) have created large-scale shocks and a pair of cavities, each 200 kpc in diameter, in the cluster's X-ray atmosphere. The energy involved approaches 10^62 erg, equivalent to a very powerful quasar. \it Chandra images have shown that similar, albeit much smaller, interactions in other systems compress and heat the gas, and there is growing evidence in other cavity systems that cool, low-entropy gas is being uplifted and redistributed throughout clusters. In some clusters, star formation and cool (10^4 K) gas are found along the edges of the radio lobes and cavities. We propose to obtain deep H(alpha) and \textitU-, \textitR-, and \textitI-band images of the cluster to examine the relationships between cool gas, star formation, and the cavity and shock systems. The proposed observations will provide constraints on the feedback process that appears to be operating in cooling flow clusters, and will provide a map of the nebular emission and young stars for future spectroscopic investigations.


National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360



NOAO >   Observing Info >   Approved Programs >   2005A-0435

noaoprop-help@noao.edu

Small NOAO Logo