LABORATORI NAZIONALI DI LEGNARO
BNCT (Boron Neutron Capture Therapy) is a therapeutic modality used to irradiate tumors cells previously loaded with the stable isotope 10B, with thermal or epithermal neutrons. This technique is capable of delivering a high dose to the tumor cells while the healthy surrounding tissue receive a much lower dose depending on the 10B biodistribution. If BNCT is to be-come a practical option, accelerator-based sources of high uxes of epithermal neutrons are essential. Generation of low energy neutron can be achieved by 7Li(p,n)7Be reaction using accelerator-based neutron source. In this study, therapeutic gain and tumor dose per target power, as parameters to evaluate the treatment quality, were calculated. The common neutron-producing reaction 7Li(p,n)7Be for accelerator-based BNCT, having a reaction threshold of 1880.4 keV, was considered as the primary source of neutrons. Energies near
the reaction threshold for deep-seated brain tumors were employed. These calculations were performed with the Monte Carlo N-Particle (MCNP) code.
Much work has been performed on development of high-ux compact proton accelerators, but a dose-limiting component remains design of the neutron production target. Specically, lithium has a low melting point (180C) and low thermal conductivity (44 W/mC). As a result of this work, a good therapeutic gain was obtained with a simple but eective beam shaping assembly.
Also, heat transfer evaluations of a lithium target designed were performed by ANSYS software. The target designed show that the peak lithium temperature can be held below 150C with indalloy or water owing by a cooper microchannels plate.