| Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2002: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 2001: ¥1,600,000 (Direct Cost: ¥1,600,000)
Fiscal Year 2000: ¥1,300,000 (Direct Cost: ¥1,300,000)
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| Research Abstract |
The solid state nuclear track detector (SSNTD) shows its characteristic feature in personal dosimetry for crews in space shuttles, separate measurement of charged particles emitted from laser-induced plasmas and many other research fields. It is indispensable for such applications to utilize well-defined data of fundamental response of SSNTDs to charged particles. In the present, however, there remains a serious problem of no common database. It is the main purpose of this research to establish a reliable database for light ions through international comparison among Universite de Franche-Conte (UFC), France, Dresden University of Technology (DUT), Germany and Kobe University of Mercantile Marine (KUMM), Japan.
At first, all the data for proton (p), deuteron (d), triton (t) and alpha-particle (α), obtained by 1999, were checked and compiled including some new data from additional experiments.
The CR-39 samples irradiated by lithium ions (Li) with energies of 4.8, 6.8 and 10.8 MeV were distributed in three teams, and then processed and analyzed independently. All data were consistent with each team. We also found out that the response function depended slightly upon the incident energy. It was considered to be caused by an existence of less sensitive layer near the surface.
Finally, the response of CR-39 detector to carbon ions (C) upto 22.5 MeV was evaluated in 2002. The deviation among three teams was enlarged, especially near the endpoint of the ion trajectory. It would be related with a steep change in the track etch rate along the ion pass. We improved the response data by introducing the multi-stage etching technique and taking a shorter etching interval.
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