Ceric-cerous sulfate dosimeter

Ceric Sulfate (or Ceric-Cerous Sulfate) Dosimeter... 

The ceric-cerous sulfate dosimeter is a chemical dosimeter acting either as a routine dosimeter or as a reference standard dosimeter for the measurement of high dose levels (Matthews, 1982). A routine dosimeter is used in radiation processing facilities for dose mapping. A reference standard dosimeter is used to calibrate radiation fields and routine dosimeters. The dosimeter is based on the reduction of cerium(IV) to cerium(in) in an aqueous solution by radiation (Matthews, 1971). Doses in the range 0.5 to 50 kGy can be determined by conventional spectrophotometric analysis in the ultraviolet region, or by measuring the difference in the electrochemical potential between the irradiated and non-irradiated solutions in an electrochemical potentiometer (Matthews, 1972 Church et al., 1976). As most dosimeters, the... 

The use of the ceric sulfate dosimeter solution is based on the radiolytic reduction of the ceric ions to cerous ions in an aqueous addic solution (Weiss 1952). 

The ceric sulfate dosimeter is sensitive to impurities, but this effect can be decreased by the addition of scavengers, e.g., cerous ions, or by preirradiation of the solution to a dose of approximately 1 kGy. Other unfavorable characteristics of the solution are its light sensitivity, energy dependence below 0.1 MeV, dose rate dependence above 10 Gy s and the need to dilute the irradiated solutions for the spectrophotometric evaluation. The temperature coefficient of the solution during irradiation is not significant in the range of 10-62°C (Matthews 1982). 

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