Karl Mannheim – ITPA Würzburg Gamma rays from the Virgo and Coma clusters of galaxies Berlin CTA-Meeting, May 4-5, 2006

Storage of (UHE) cosmic rays Clusters of Galaxies Storage of (UHE) cosmic rays Supernova-driven winds Radiojets from Active Galactic Nuclei Acceleration of (UHE) cosmic rays Cluster merger shocks Accretion shocks Dynamical relaxation shocks Dark matter annihilation Largest mass concentrations Small-scale clumps dominance: Sorting in dM/R2 Galactic Center Nearest halo clump (unidentified EGRET?) Nearest rich clusters (Virgo, Coma, Perseus) Nearest dwarf galaxies (Sagittarius, Draco)

Galactic Vicinity (200 kpc)

Local Group (2 Mpc)

Local Universe (60 Mpc)

Local Universe (300 Mpc)

 Coma cluster Virgo cluster 

Cosmic rays in nearby clusters of galaxies Pfrommer et al.: Cosmic ray propagation model fitted to radio and X-ray observations, employing hydrodynamical code for of intracluster medium (g-ray fluxes > 50 GeV)

Cosmic rays in Coma Völk et al.: Cosmic ray propagation Reimer et al. Cosmic ray propagation Berrington & Dermer: Cluster merger shock

M 87 / Virgo Cluster C=40 C=335 Control astrophysical backgrounds: DarkSusy scan C=40 C=335 Control astrophysical backgrounds: AGN in M87 CRp – interactions MAGIC observations have started in May 2005 Targeted observations seem promising with new – generation experiments

M87 SED (ICRC)

2DM ds Structure Formation ART Code (A. Klypin et al.) 3 £ 1014 solar masses; 9 million particles („Virgo Cluster“) (sub)structure down to 3 £ 107 solar masses: clumps! Structure Formation 2DM ds D. Elsaesser, S. Gottloeber, A. Khalathyan and M. Steinmetz

Clusters are cutting-edge targets for current IACTs Summary Clusters are cutting-edge targets for current IACTs Rich potential for astrophysics, cosmology, and particle physics Origin of UHE cosmic rays Dark matter annihilation Role of nonthermal plasma in structure formation … northern location prefered for a dedicated„cluster mission“with future CTAs…