The Tibet air shower array experiment has been conducted at Yangbajing (90.522°E, 30.102°N; 4300m above sea level) in Tibet, China, Since 1990. A search for extended emission from Cygnus region was carried out using data taken from the Tibet III (1999 November -2005 November) arrays. Spreading across -3° to ~3° in Galactic latitude and 65°to ~85°in Galactic longitude, an excess that peaks at DEC ~36.2°N and R.A. ~304.6° in the Cygnus region is detected at a significance level of ~5.2σ, coincident with the extended Milagro source locating at(304.83°,36.83°). The spectra of gamma rays emission from this Milagro source and from Cygnus region have been analyzed preliminarily in TeV energy range.

asγ 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 695-698