LET DISTRIBUTION AND ABSORBED DOSE IN SZ-3 RECOVERER

In order to measure the absorbed dose and the dose equivalent induced by heavy ions which enter the space capsule inside, a solid state nuclear track detector is installed in the inner wall of SZ-3 recoverer. This detector is composed by the sandwich of CR-39 sheets and aliminium sheets. The flight time of the detector on board of SZ-3 is about 162 h. After the chemical etching for recoverd CR-39 sheets, we scaned and measured the ion track spots on the CR-39 sheets. Refering to the calibration value for different ions provided by heavy ion accelerator experiment and subtracting the background provided by the contrast samples on the ground, the linear energy transfer （LET） distribution in recoverer are obtained. When the linear energy transfer （LET） is larger than the threshold of the detector, the integral intensity is （4.667±0.071）×10^-5cm^-2·s^-1·sr^-1. For LET ＞ 12.6keV/μm （H₂O）, the total absorbed dose and the total dose equivalent are （23.50±0.46）μGy and （355.6±9.7）μSv, respectively. The relationship between the total dose equivalent and the thickness of shield are obtained.