Dose Rate and Spectral Measurements From Pulsed X-Ray Generators

High dose‐per‐pulse electron beam dosimetry: Usability and dose‐rate independence of EBT3 Gafchromic films

“…and show that we did not detect any differences between film and TLD doses; two independently calibrated dosimeters relying on different physical/chemical processes. This agreement of responses over the whole dose‐rate range studied, together with the previously reported dose‐rate independence of TLD shows that EBT3 Gafchromic films are dose‐rate independent over the explored range.…”

“…No dose‐rate dependence was found for LiF‐100 TLDs. No significant saturation was found either by Tochilin et al who investigated the dose‐rate dependence of LiF and CaF TLDs using different pulsed electron and photon sources where Ḋ p could be varied between 10 2 and 10 9 Gy/s. Also, more recently, similar results were reported by Karsh et al for a Ḋ p between 0.3 × 10 9 and 15 × 10 9 Gy/s using the same beam as the one used for the EBT film dose‐rate dependence study mentioned above.…”

“…On the prototype linac, we measured the Ḋ p dependence of EBT3 films over the range from 7 × 10 3 to 8 × 10 6 Gy/s. Two different methods were used: the analysis of the correlation of the dose with the charge of electrons exiting the machine and the direct comparison with a dose‐rate independent dosimeter: TLD‐100 …”

“…Two different methods were used: the analysis of the correlation of the dose with the charge of electrons exiting the machine and the direct comparison with a dose-rate independent dosimeter: TLD-100. 23,29,30 Correlation between dose-per-pulse (D p ) and charge per pulse (C p ): The evaluation of the Ḋ p dependence of EBT3 films was first investigated by studying the correlation between D p as measured by films in a given geometry, and C p as measured by the beam monitoring system for a given w. It was assumed that the torus and collimator current measurement were free from saturation effect and that the relative contribution from secondary electrons to the signals, if present, was proportional to the primary fluence. The fact that w was fixed ensured then that C p was proportional to Ḋ p .…”

Experimental validation of photon-heating calculation for the Jules Horowitz Reactor

“…The global experimental uncertainty of the calibration factor F c (practically the slope of the straight line Q¼F c  K air ) varies from 0.2% to 3.6% (1σ) depending on dosimeter type and pillbox material: it takes into account the repeatability, reproducibility and counting uncertainties during the calibration step. The luminescent relative photon energy response only depends on the received dose: it is assumed to be independent of the photon energy [9,10] in the AMMON photon spectrum energy range.…”