A Preliminary Study for Dose Calculation using optically Stimulated Luminescence Dosimeters in High-Energy Radiation

Background/Objectives: To determine the reproducibility, homogeneity, and sensitivity correction factor of optically stimulated luminescence dosimeters (OSLDs) for accurate measurement in Co-60. Methods/Statistical analysis: In this study, ananoDotOSLD (Landauer, Inc., Glenwood, USA), a Micro Star read out device (Landauer, Inc., Glenwood, USA), and a Co-60 Theratron 780 irradiator (AECL, Kanata, Canada) were used for the experiments. OSLDs were divided into three groups by radiation sensitivity and each consisted of dosimeters with radiation sensitivity variations within ± 1.5%. The dosimetric characteristics of OSLD were evaluatedin 60-Co. Findings: The division into three groups was performed to place an error within ± 1.5% on the basis of the normalized relative sensitivity equaling1.00. The first group(A) contained 30 devices within the range of 1.015 to 1.045, the second group (B, 26EA) within 0.985 to 1.015, and the third group (C, 19EA) within 0.955 to 0.985. The reproducibility evaluation for OSLD is expressed with a CoV and compared. All of the reproducibility was within 2.0%: The A group was within the .66-1.94%range, the B group within.84-1.99%, and the C group within 0.54%-1.88%. The evaluation of batch homogeneity is expressed as the CoV in the whole group and the A, B, and C groups’ values were 0.38%, 1.48%, and 1.47%, respectively. Improvements/Applications: This study intended to improve the accuracy of dose evaluations with Co-60 (r-ray) by using sampling and grouping and by applying an Element Correction Factor (ECF) in the process of using OSLDs.