Stimulated by the recent HESS galactic survey which discovered 14 new TeV gamma-ray sources, it is now important to measure 100 TeV gamma rays from celetial sources to locate possible cosmic-ray accelerators up to PeV energies in our galaxy. The Tibet air shower array (37,000m2), located at 4,300 m above sea levelin Tibet, is a wide field-of-view gamma-ray telescope above TeV energies. We will report on a search for 100 TeV celetial gamma rays with the Tibet air shower array. In addition, we have a plan aiming at 100 TeV gamma-ray astronomy by adding a large underground water Cherenkov muon detector array (approximately 10,000m2) to the existing Tibet air shower array.

The Tibet ASgamma collaboration

Proceedings of the 30th International Cosmic Ray Conference; Rogelio Caballero, Juan Carlos D'Olivo, Gustavo Medina-Tanco, Lukas Nellen, Federico A. Sánchez, José F. Valdés-Galicia (eds.); Universidad Nacional Autónoma de México, Mexico City, Mexico, 2008; Vol. 2 (OG part 1), pages 575-578