| 摘要 |
PROBLEM TO BE SOLVED: To quantitatively evaluate a radiation amount with one thermofluorescent dose measuring element by distinguishing gamma rays and neutron rays from the other radiations. SOLUTION: Tb<SB>4</SB>O<SB>7</SB>powder of 0.06 wt.%, Sm<SB>2</SB>O<SB>3</SB>powder of 0.03 wt.% and Gd<SB>2</SB>O<SB>3</SB>powder of 0.36 wt.% are added to CaF<SB>2</SB>powder and uniformly mixed. The mixed powder is filled into a mold and is subjected to pressure forming in a disc shape. It is further sintered at 1100°C for two hours in air atmosphere to obtain a sintered body of a thermofluorescent dose measuring element. When each radiation of ultraviolet rays, X-rays, gamma rays and neutron rays is applied to the sintered body and a glow peak curve 1 is evaluated, peaks of the ultraviolet rays and the X-rays are observed near 100°C, while those of the gamma rays and the neutron rays are observed near 150°C. This shows that the peaks of gamma rays and neutron rays can be distinguished from those of other radiations even in a mixed radiation field. Moreover, the radiation amount of each radiation can be quantitatively evaluated from the area of the part enclosed by the glow peak curve and a heating temperature axis 2. COPYRIGHT: (C)2009,JPO&INPIT
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