Effect of Pre-gamma Irradiation on Cr-39*
نویسندگان
چکیده
The effect of pre-gamma irradiation on track density, bulk etch rate and light absorbance in CR-39 was investigated. CR-39 detectors were irradiated with gamma doses over a range of 0 to 280 kGy (0 to 28 Mrad). The detectors were overlaid with 0.77 mm of polyethylene and exposed to a known fluence of 252Cf spontaneous fission neutrons. All detectors were then etched in 6.25N sodium hydroxide solution at 70°C for 4 hours and track densities were determined with an optical microscope. The bulk etch rates were determined by measuring the change in thickness before and after etching. The net track density decreased and the bulk etch rate increased non-linearly with increasing gamma doses. UV spectrophotometric measurements showed significant changes in light absorbance for gamma irradiated CR-39.
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