Journal Article

DKFZ-2024-00804

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Converter thickness optimisation using Monte Carlo simulations of Fluorescent Nuclear Track Detectors for neutron dosimetry

Schmidt, S. (First author)DKFZ* ; Stabilini, A. ; Thai, L. J.DKFZ* ; Yukihara, E. G. ; Jäkel, O.DKFZ* ; Vedelago, J. A. (Last author)DKFZ*

2024
Elsevier Science Amsterdam [u.a.]

Please use a persistent id in citations: doi:10.1016/j.radmeas.2024.107097

Abstract: 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.

Note: #EA:E040#LA:E040#

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Contributing Institute(s):

1. E040 Med. Physik in der Strahlentherapie (E040)

Research Program(s):

1. 315 - Bildgebung und Radioonkologie (POF4-315) (POF4-315)

Appears in the scientific report 2024

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Database coverage:
Clarivate Analytics Master Journal List ; Current Contents - Physical, Chemical and Earth Sciences ; Ebsco Academic Search ; Essential Science Indicators ; IF < 5 ; JCR ; Nationallizenz ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

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