The dependence of N KR versus K R: the initial, thermal, volumetric recombination and screening effect on the efficiency of collected charges on the calibration of si HDR1000 plus well chambers with 192Ir HDR sources * *The authors have declared that no competing interests exist.All relevant data are within the paper and its supporting information files.The study meets the regulation

Abstract

By using the statistical techniques of the ANOVA means test and regression, it was found that the calibration factor of Standard Imaging (SI) model HDR 1000 plus chambers presents a quadratic dependence with the Reference air kerma rate (from 6.9 mGy h−1 to 43.9 mGy h−1). In order to understand and correct this dependency one model is presented for total recombination: where is the initial recombination, the thermal diffusion recombination, the volumetric recombination and the screening for the currents/charges collected at the potential differences of 300 and 150 V. In conclusion, the total recombination is composed by one with a constant contribution of 0.019%, one k d contribution of 0.017%, one contribution from 0.022% to 0.138%, and the effects from 0.002% to 0.09% in the range of rate above. However, when this model for is applied to try to correct the quadratic dependence of the versus explicitly there is no improvement in the variation range of 0.5% of the versus Nonetheless, it allows to obtain values consistent with a ≤ 0.7%, which is less than 1.25% reported in the literature by ADCLs or SSDLs.