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PubMed · 7652009

A design study for an accelerator-based epithermal neutron beam for BNCT.

D A Allen·T D Beynon
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Abstract

An achievable design concept for a boron neutron capture therapy (BNCT) facility, based on a high-current, low-energy proton accelerator, is described. Neutrons are produced within a thick natural lithium target, under bombardment from protons with an initial energy between 2.5 and 3.0 MeV. The proton current will be up to 10 mA. After gamma-ray filtering, the neutrons are partially moderated to epithermal energies within a heavy-water moderator, poisoned with 6Li to remove thermal neutrons. Monte Carlo modelling has been used to predict system performance in terms of neutron fluence rate and neutron and gamma-ray dose at the patient position. The relationship between the system performance and key parameters, such as proton energy, moderator depth and 6Li concentration, has been investigated. With a proton current of 10 mA, the facility is capable of providing a therapy beam with a useful neutron fluence rate of 10(9) cm-2 s-1 and a neutron dose per unit fluence of less than 6 x 10(-13) Gy cm2, with a gamma-ray contamination of the therapy beam of about 10(-13) Gy cm2.

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Biophysical PhenomenaBiophysicsBoron Neutron Capture TherapyEquipment DesignFast NeutronsHumansModels, BiologicalMonte Carlo MethodNeoplasmsParticle AcceleratorsProtonsRadiotherapy Planning, Computer-AssistedJournal Article

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BibTeXRIS

D A Allen, T D Beynon. 1995. A design study for an accelerator-based epithermal neutron beam for BNCT.. https://doi.org/10.1088/0031-9155%2F40%2F5%2F007

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