Sonal Kadam

Environmental monitoring using LiMgPO4:Tb, B based optically stimulated luminescence dosimeter

A new optically stimulated luminescence based environmental dosimeter (EnOSLD) was developed using LiMgPO 4 :Tb, B phosphor (LMP). The dosimeters were deployed along with the conventional thermoluminescent based environmental thermoluminescent detectors (EnTLD) for a period of six quarters in the environs of a nuclear power plant in India. The dose estimated by the EnOSLDs was compared with that of the dose estimated by EnTLDs. The mean ratio of the doses measured by thermoluminescent detector to that measured by optically stimulated luminescence dosimeters was found to be 1.04 ± 0.11. The results show that LMP based OSLDs can be used as environmental dosimeter.

The thermoluminescence study of epoxy based LiF:Mg,Cu,P dosimeters

The LiF:Mg,Cu,P phosphor is the most investigated phosphor in radiation dosimetry. Results on thermoluminescence of the epoxy based LiF:Mg,Cu,P dosimeters irradiated with gamma radiations are presented and compared with results of LiF:Mg,Cu,P powder. The glow curve structure of both LiF powder and dosimeter are same and only difference is found in the glow curve peak temperature. The LiF dosimeters were made from the 5012A and 5012B epoxy. The dosimeters had a mass of about 18 mg, 5.0 mm diameter and 0.5 mm thickness. The sensitivity variation of the dosimeters for exposure to 60Co gamma rays at different angles of incidence of the radiation is found to be within 4%. Its minimum detectable dose is about 3020 µGy. The epoxy based dosimeters withstand different environment and it can be used with general TL reader without need of any special design due to its small size and plane surface.