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Abstract: EPID dosimetry has known drawbacks. The main issue is that a measurable residual signal is observed after the end of irradiation for prolonged periods of time, thus making measurement difficult. We present a detailed analysis of EPID response and suggest a simple, yet accurate approach for calibration that avoids the complexity of incorporating ghosting and image-lag using the maximum integrated signal instead of the total integrated signal. This approach is linear with dose and independent of dose rate. [Copyright &y& Elsevier]

Abstract: Calorimeters for dose measurement at low-energy electron accelerator energies (80–120keV) are described. Three calorimeters with different characteristics were designed and their dose response and measurement uncertainties were characterized. The heated air between the beam exit window and the calorimeter absorber influences significantly the response of the calorimeter and a thermal model was applied to quantify this effect. All three calorimeters are capable of measuring absolute dose, and can thus be used for calibration of other dosimeters. [Copyright &y& Elsevier]

A method for calibration of thin-film dosimeters irradiated with 80–120 keV electrons has been developed. The method is based on measurement of dose with a totally absorbing graphite calorimeter, and conversion of dose in the graphite calorimeter to dose in the film dosimeter by Monte Carlo calculations. A thermal model was developed to estimate the temperature contributions from the air above the calorimeter that is heated by the electron beam.As an example, Risø B3 thin-film dosimeters were calibrated by 80–120 keV electron irradiation and compared with a calibration carried out at 10 MeV electron irradiation. The two calibrations were found to be equal within the estimated uncertainties of ±10% at 1 s.d. [Copyright &y& Elsevier]