GEANT4 simulation of a range verification method using delayed γ spectroscopy of a 92Mo marker. (15th December 2020)

• Record Type: Journal Article
• Authors: Kasanda, E; Burbadge, C; Bildstein, V; Turko, J; Spyrou, A; Höhr, C; Mücher, D
• Is Part Of: Physics in medicine & biology. Volume 65:Number 24(2020:Dec.)
• Publication Date: 2020-12-15
• Subjects: proton therapy -- range verification -- GEANT4 -- simulation -- tumour marker -- γ spectroscopy; Biophysics -- Periodicals; Medical physics -- Periodicals; 610.153
• DOI: 10.1088/1361-6560/abbd15
• Languages: English
• ISSNs: 0031-9155

Abstract

Abstract: In this work, we propose a novel technique for in-vivo proton therapy range verification. This technique makes use of a molybdenum hadron tumour marker, implanted at a short distance from the clinical treatment volume. Signals emitted from the marker during treatment can provide a direct measurement of the proton beam energy at the marker's position. Fusion-evaporation reactions between the proton beam and marker nucleus result in the emission of delayed characteristic γ rays, which are detected off-beam for an improved signal-to-noise ratio. In order to determine the viability of this technique and to establish an experimental setup for future work, the Monte Carlo package GEANT4 was used in combination with ROOT to simulate a treatment scenario with the new method outlined in this work. These simulations show that the intensity of delayed γ rays produced from competing reactions yields a precise measurement of the range of the proton beam relative to the marker, with sub-millimetre uncertainty.