[1] UNIV TOKYO,CTR RADIOISOTOPE,BUNKYO KU,TOKYO 113,JAPAN
[2] TOKYO INST TECHNOL,DEPT APPL PHYS,MEGURO KU,TOKYO 152,JAPAN
[3] KITASATO UNIV,SCH HYG SCI,DEPT CHEM,SAGAMIHARA,KANAGAWA 228,JAPAN
[4] JISSEN WOMENS UNIV,FAC GEN EDUC,HINO,TOKYO 191,JAPAN
[5] NATL LAB HIGH ENERGY PHYS,OHO,IBARAKI 305,JAPAN