Heating vs. Cooling in Galaxies
and Clusters of Galaxies

MPA/ESO/MPE/USM Joint Astronomy Conference

August 6 - 11, 2006 - Garching, Germany

NEWS: 15/09/2006

Updated information available on the proceedings webpage!

The aim of the conference is a review of our knowledge of the physical processes controlling the state of the dense, central intracluster medium in galaxy clusters and to dicuss their analogy to feedback process in regulated galaxy formation.
Detailed multiwavelength observations suggest that the dense plasma regions at the centers of galaxy clusters, previously thought to harbour cooling flows, are subject to a delicate balance between heating and cooling, which substantially reduces mass condensation and star formation rates. While these regions are quite complex, the rich observational details now becoming available can guide understanding and modelling. The aim of this conference is to provide a synthesis of all the observational evidence and to confront it with astrophysical modelling. Analogous issues arise in the models of galaxy formation where the observed properties and the evolution of the galaxy population can only be explained if gas cooling and star formation are assumed to be regulated by feedback heating. The conference will explore possible connections between these two areas.
In recent years the effort to understand cluster cooling cores has grown both in terms of observation (in particular in X-rays with the Chandra and XMM-Newton satellites) and in terms of detailed numerical hydrodynamical simulations. A review of the state of the subject is thus timely. Also, in recent years it has been much more generally appreciated that the suppression of gas cooling in the center of galaxy clusters may be a model for the effects of feedback in galaxy and structure formation in general. In our meeting we consequently broaden the view to include feedback and self-regulation during galaxy formation.


  • Evidence for cooling, cold material, and star formation in the centers of galaxy clusters and elliptical galaxies (results from observations in X-rays, optical, IR, radio, absorption studies and other diagnostics)
  • Heating by the AGN-intracluster medium interaction and by other processes; confrontation with observed cooling core structure (observational results, particularly in X-rays and radio, and theoretical modelling and simulations)
  • The entropy structure of the intracluster medium and chemical enrichment as signatures of feedback heating in the past
  • The need for feedback regulation in galaxy formation (detailed comparison of model predictions and observations), modelling of feedback during galaxy formation both from stars/supernovae and from AGN

Scientific Organizing Committee

M. Arnaud, M. Begelman, H. Boehringer, M. Donahue, A. Fabian, G. Hasinger, T. Heckman, C. Jones, B. McNamara, T. Ohashi, F. Owen, M. Pettini, T. Reiprich, A. Renzini, P. Rosati, C. Sarazin, N. Soker, R. Sunyeav, S. White

Invited Speakers

M. Arnaud, S. Borgani, R. G. Bower, M. Brueggen, E. Churazov, M. Donahue, A. Fabian, C. Jones, G. Kauffmann, B. McNamara, M. Ruszkowski, C. Sarazin, M. Voit, S. White

Local Organizing Committee

F. Braglia, E. Churazov, M. Depner, R. Fassbender, A. Finoguenov, W. Frankenhuizen, A. Langer, D. Pierini, G. Pratt, C. Rickl, P. Rosati, J. Santos, P. Schuecker, A. Simionescu, Y.Y. Zhang