TY  - JOUR
AU  - Schmidt, Stefan
AU  - Stabilini, Alberto
AU  - Thai, Long-Yang Jan
AU  - Yukihara, Eduardo G.
AU  - Jäkel, Oliver
AU  - Vedelago, Jose Alberto
TI  - Converter thickness optimisation using Monte Carlo simulations of Fluorescent Nuclear Track Detectors for neutron dosimetry
JO  - Radiation measurements
VL  - 173
SN  - 1350-4487
CY  - Amsterdam [u.a.]
PB  - Elsevier Science
M1  - DKFZ-2024-00804
SP  - 107097
PY  - 2024
N1  - #EA:E040#LA:E040#
AB  - Secondary neutrons generated during ion beam radiotherapy present a concern due to the potential dosedeposition beyond the treatment volume, thereby elevating the risk of inducing secondary tumours. Theseneutrons can possess energies comparable to those of the primary ions, reaching magnitudes of severalhundred MeV, posing a challenge for neutron detectors. Fluorescent Nuclear Track Detectors (FNTDs) arepromising detectors for high-energy neutron dosimetry given their capability to detect particles with a lowlinear energy transfer. In this work, the sensitivity of FNTDs to neutron energies reaching 20 MeV was analysedby experiments and Monte Carlo (MC) simulations, quantifying the recoil proton yield of FNTDs combinedwith polyethylene (PE) converters of different thicknesses. The FNTDs were read out using a dedicated FNTDreader, demonstrating a reasonable uncertainty by analysing a detector area of 0.1 mm2. Investigations ofdifferent converter thicknesses reveal optimal detector sensitivity between 0.5 mm to 1.0 mm for a 241AmBesource, yielding a maximum sensitivity of (22.7±3.4) tracks mSv−1 mm−2. Similar converter-FNTD configurationswere assessed through MC simulations using FLUKA, yielding a correlation between detector sensitivity andconverter thickness. Furthermore, an enhanced detector sensitivity for neutron energies up to 20 MeV wasfound for the PE converter thickness of 4.0 mm. The MC simulations can be used to optimise FNTD detectorconfigurations for measuring higher neutron energies by maximising the recoil proton yield.
LB  - PUB:(DE-HGF)16
DO  - DOI:10.1016/j.radmeas.2024.107097
UR  - https://inrepo02.dkfz.de/record/289482
ER  -