High Dose Fast Neutron Dosimetry Using Padc Plastic Nuclear Track Detectors and Grey Level Analysis

Abstract

The objective of this work is to demonstrate the possibility of performing fast neutron dosimetry up to 5 Sv using optical absorbance of polyallyl diglycol carbonate (PADC) detectors, obtained through grey level analysis of PADC images acquired with a commercial track-counting dosimetry system, and estimate the uncertainties involved. PADCs were irradiated with doses from 100 mSv to 5 Sv (252Cf source) and etched. PADC images were acquired using the TASLIMAGE™ Neutron Dosimetry System (Track Analysis Systems Ltd.) and analysed to obtain the grey levels and the optical absorbance. The absorbance from different detectors and batches was analysed to determine the uncertainties involved, from which the final uncertainty in the method, ~30% and dominated by the uncertainty in the calibration curve, was estimated. A dose estimation <2 Sv can also be performed using a 'universal curve' by normalising the absorbance to that of a detector irradiated with 1 Sv. The data presented here allows the extension of the dose range of track counting systems using no additional equipment, only the images already acquired by the systems.

A Monte Carlo study on the secondary neutron generation by oxygen ion beams for radiotherapy and its comparison to lighter ions

“…The charged secondary fragments generated inside the phantom affect the secondary neutrons detection. This is particularly significant for track detectors (Stabilini et al 2018, 2020, Becker et al 2022, where a clear distinction between the secondary protons generated by the primary beam and the recoil protons used for neutron detection is needed. Therefore, further study of the proton fluence was carried out for the SOBP generated with the oxygen ions beam in the same positions where the secondary neutrons were scored.…”