A Correction Factor for Effects of Scattered X-rays at Calibration of Ionization Chambers in Low Energy X-ray Standard Fields
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چکیده
A correction factor ks is related to contributions of scattered photons at calibration in standard X-ray fields. We obtained values of ks for spherical and parallel-plate ionization chambers in low energy X-ray fields experimentally. Signal currents from these chambers were measured using copper plate collimators with different diameter holes to vary the field size. To derive ks values, the measured data were analyzed using a simple model. It was found that the value of ks increases with the increase of the effective energy of X-rays.
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تاریخ انتشار 2007