RESUMO
A novel optically stimulated luminescence (OSL) detector containing isotopically enriched boron was developed for thermal neutron dosimetry. Alumina containing isotopically enriched boron (Al2O3:B) was synthesised by the sol-gel method. The Al2O3:B was annealed up to ~1800 K. For X-ray diffractometer (XRD) analysis, the diffraction pattern of the Al2O3:B had reflex peaks corresponding to α-Al2O3. The sensitivity of Al2O3:B to photons was slightly 2% of that of a commercial Al2O3:C. The Al2O3:B detector had satisfactory linearity in X-ray dose measurement. A thermal neutron field was constructed using a 241Am-Be neutron source and graphite blocks. A pair of Al2O3:10B and Al2O3:11B detectors were set in the thermal neutron field. The response of Al2O3:10B was larger than that of Al2O3:11B owing to the 10B(n,α)7Li reactions. The sensitivity of Al2O3:10B to thermal neutrons was estimated to be two orders less than the photon sensitivity. Therefore, the pair of Al2O3:10B and Al2O3:11B detectors were useful for thermal neutron dosimetry.
Assuntos
Óxido de Alumínio/química , Boro/química , Nêutrons , Dosímetros de Radiação , Desenho de Equipamento , Fótons , Sensibilidade e Especificidade , Difração de Raios XRESUMO
New radiophotoluminescence (RPL) phosphate glass containing (6)Li was successfully made from the powder of NaPO(3), Al(PO(3))(3), LiOH, HPO(3) and AgCl. The ternary diagram of NaPO(3)-Al(PO(3))(3)-LiPO(3) has clarified the region where satisfactory RPL characteristics of the glass are kept up. The synthesised phosphate glass indicated good RPL characteristics on the condition that the content of LiPO(3) was below 10 wt%. Gamma-ray irradiation experiments showed that the newly synthesised phosphate glass had satisfactory linearity and wide dynamic range in dose measurement and low variation in sensitivity. It was confirmed from thermal neutron irradiation experiments that a pair of the newly synthesised phosphate glass containing enriched (6)Li and (7)Li, or (n)Li and enriched (7)Li could be effectively used for the evaluation of thermal neutron dosimetry.
