LIBRARIES Accelerator-Based Boron Neutron Capture Therapy

Boron Neutron Capture Therapy (BNCT) is a promising therapy modality for cancer. Clinical trials using BNCT are underway in the US. BNCT works by a selective loading of tumor cells with 1oB and subsequent irradiation of the tumor with thermal neutrons. The reaction 'lB(n,ac) is induced and releases approximately 2.3 MeV of energy, most of which is deposited locally. In Accelerator-Based BNCT (AB-BNCT), neutrons for this therapy are produced using ion induced reactions. Three reactions, 7Li(p,n) Ep=2.5 MeV, 9Be(p,n) Ep=3.0-4.0 MeV, and 9Be(d,n) Ed=2.6 MeV are investigated here. Complete data for the 9Be(p,n) reaction were not previously available. Therefore, 28 thick target neutron spectra were measured, on an absolute basis, using time-of-flight techniques. Proton energies 3.0, 3.4. 3.7. and 4.0 MeV, and laboratory angles 0-145 degrees were used. The absolute accuracy of the data (better than 25 % for most neutron energies) was confirmed by measuring a different reaction with a known spectrum. Using the three reactions, Monte Carlo techniques were used to design therapy beams for AB-BNCT. The reaction 7Li(p,n) yielded the highest dose rates. However, given lithium's poo