NIRS report concerning the cyclotron usages. FY 2000

This report describes the National Institute of Radiological Sciences (NIRS) cyclotron usages concerning of: Operation and improvement-development of the cyclotrons in 2000 (total 1,302 hr operation, development of the insulating septum, renewal of the magnetic channel and radiofrequency (RF) pre-amplifier, and improvement of the magnetic interference); Development of neutron detectors in the cosmic environment (the phoswich detector, low-pressure proportional counter, bubble dosimeter and new type phoswich detector); Development of detectors of charged particle components in the cosmic radiation (Liulin-4J and position sensitive silicon detector); Measurement of the energy and angular distribution of secondary electrons from water vapor with heavy-ion impact; Phase II clinical trials of proton beam therapy for ophthalmological tumors (34 patients in 1996-2000 and survival rate 100% within 3 years); Application of cyclotrons for RI production (mainly, 11C, 13N, 15O and 18F for basic and clinical PET); Studies on the spread-out peak of proton beam (for radiotherapy); and Related materials to above (details). (N.I.)