Monte Carlo and experimental dosimetry of an brachytherapy seed
The Model 6711 seed. The seed is cylindrically symmetric around its longitudinal axis.
A radiograph of five decayed seeds showing variation in end weld thickness and differences in rod position.
Details of source wire beveling at 150x magnification. The images were taken with an electron microscope.
A plot of the ratio demonstrating the angular dependence of the energy response function. The dose rates in the experimental setup were evaluated using the OMCF and ETL estimators with TLDs placed in water, solid water, and PMMA.
Dose-rate-constant results for the 6711. All values represent absorbed dose rates in liquid water, though the phantom media are not necessarily liquid water. Methods: =Monte Carlo calculation, =Measurement using detectors, =Includes a PMMA to water correction.
Calculation of uncertainties associated with evaluations of the dose-rate constant.
The radial dose function, , for the Model 6711 and other seeds which contain silver markers. In this study, the energy response function applied to transverse axis TLD results is derived from the ETL estimator at distances of 0.2, 0.5 and 1.0, and the OMCF estimator at other distances.
MC and TLD anisotropy function data for the 6711 seed in water. The results in this table account for the angular dependence of the energy response function using the ETL estimator at all distances and angles.
A summary of our findings regarding . Totals were calculated by combining all significant contributions in quadrature. Key: =Not performed as described in Sec. III B; =differences were less than statistical error of MC calculation.
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