Observation of clusters of galaxies with the CANGAROO-III telescope system

More than forty gamma-ray sources have been detected by atmospheric Cherenkov telescopes at TeV energies. Although there are many theoretical predictions on the possible gamma-ray ux es from these gigantic objects assuming various emission mechanisms, no cluster of galaxies have been proven to be a TeV gamma-ray emitter until now. We have observed a couple of clusters of galaxies in the southern sky with the CANGAROO-III atmospheric Cherenkov telescope system in 2005-2006, and preliminary results on the analysis to search for gamma-ray signature are reported.