1. Astrophysical Institute and Department of Physics & Astronomy, Ohio University, Clippinger Laboratories, Athens, Ohio 45701, USA
2. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA
3. MIT Center for Space Research, 1 Hampshire Street, Cambridge, Massachusetts 02139, USA
4. National Radio Astronomy Observatory, Very Large Array, Socorro, New Mexico 87801, USA
5. Astronomy Department, University of Virginia, Box 3818, Charlottesville, Virginia 22903, USA
6. Institute for Astrophysical Research, Boston University, Boston, Massachusetts 02215, USA
7. Present address: University of Wollongong, Wollongong, New South Wales, Australia

Correspondence to: B. R. McNamara¹ Correspondence and requests for materials should be addressed to B.R.McN. (Email: mcnamarb@ohio.edu).

Abstract

Most of the baryons in galaxy clusters reside between the galaxies in a hot, tenuous gas¹. The densest gas in their centres should cool and accrete onto giant central galaxies at rates of 10–1,000 solar masses per year¹. No viable repository for this gas, such as clouds or new stars, has been found¹. New X-ray observations, however, have revealed far less cooling below X-ray temperatures than expected², altering the previously accepted picture of cooling flows. As a result, most of the gas must be heated to and maintained at temperatures above 2 keV (ref. 3). The most promising heating mechanism is powerful radio jets emanating from supermassive black holes in the central galaxies of clusters⁴. Here we report the discovery of giant cavities and shock fronts in a distant (z = 0.22) cluster caused by an interaction between a radio source and the hot gas surrounding it. The energy involved is 6 10⁶¹ erg, the most powerful radio outburst known. This is enough energy to quench a cooling flow for several Gyr, and to provide 1/3 keV per particle of heat to the surrounding cluster.

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