JOINT EMULSION CHAMBER EXPERIMENT AT PAMIR

Research Project

Project/Area Number	58420009
Research Category	Grant-in-Aid for General Scientific Research (A)
Allocation Type	Single-year Grants
Research Field	核・宇宙線・素粒子
Research Institution	Waseda University
Principal Investigator	FUJIMOTO Yoichi 早稲田大学, 公・私立大付置, 教授 (20063290)
Project Period (FY)	1983 – 1985
Project Status	Completed (Fiscal Year 1985)
Budget Amount *help	¥20,500,000 (Direct Cost: ¥20,500,000) Fiscal Year 1985: ¥1,000,000 (Direct Cost: ¥1,000,000) Fiscal Year 1984: ¥1,000,000 (Direct Cost: ¥1,000,000) Fiscal Year 1983: ¥18,500,000 (Direct Cost: ¥18,500,000)
Keywords	COSMIC RAYS / EMULSION CHAMBER / PAMIR / SUPER HIGH ENERGY / COSMIC RAY FAMILIES
Research Abstract	A huge emulsion chamber was constructed on Sep. 1958 at Pamir plateau(4,300 m) by the collaboration with Soviet Cosmic-Ray researchers. The Chamber is of two storey structure, upper(Gamma-block) and lower (Hadron blocks) chambers with 60 cm of carbon target in between, and the area is extended 170 <m^2> . Photo sensitive materials (X-ray-films and nuclear emulsion plates) were sent back to Japan on October 1960 after about two years exposures. The processing of photo-sensitive materials was completed successfully, and the detection and measurement of super high energy cosmic-ray families are just started in order to get new informations on the characteristics of particle interactions above <10^(16)> eV regions. It is remarkable that an extremely high energy cosmic-ray families with huge halo in the center was found with total observed energy greater than 25,000 TeV and the preliminary analysis tells the nature of particle production are not on the extrapolation of ordinary type of multiple particle production and requires introduction of new type of interaction. There are found a number of high energy families greater than 1,000 TeV of observed energies and they will provide important informations on the characteristics of high energy particle interactions.