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The radiation tolerance testing of materials or opto-electronic components in a nuclear reactor requires a careful determination of the different components of the mixed gamma-neutron field. While the characterization of the neutron field can be performed using, for example, activation foils and validated by Monte-Carlo computation codes, the experimental measurement of the in-reactor gamma dose rate requires the use of costly ionization chambers. In this paper, we evaluate the possibility of using Red Perspex from Hanvell Technologies for routine gamma dosimetry in mixed gamma neutron field. Self-powered gamma detectors and ionization chambers were used as reference dosimeters. We show that the accuracy of the Red 4034 dosimeter's is better than 10% in mixed gamma-neutron fields. [ABSTRACT FROM AUTHOR]

Abstract: Gamma radiation-induced optical absorption in 75SiO2–22Na2O–3CaO (wt.%) multi-component glass and in the same glass additionally doped with 0.05wt.% CeO2 has been studied, with irradiations performed at 70, 200, and 350°C, 25kGy/h up to a dose of 0.6MGy. For the undoped glass irradiation at 70°C produces strong optical absorption from 700nm down to the UV. Irradiation at 200°C gives a lower level of optical absorption with a similar band composition. No induced optical absorption has been detected after irradiation at 350°C. Annealing at 200°C for 24h completely suppresses the induced optical absorption. Introduction of cerium increases the level of induced absorption in the UV range for irradiation at 70°C, and also creates bands stable up to 350°C. The results show that silica and sapphire, which are considered as main candidate materials for ITER diagnostic windows and other optical components, can potentially be complemented with multi-component silicate glasses. These materials may allow one to control the radioluminescence, and in addition provide a range of refractive indices required for achromatic lenses. [Copyright &y& Elsevier]