Conceptual Design of a Californium-Based Epithermal Neutron Beam for Boron Neutron Capture Therapy Using a Subcritical Multiplying Assembly

摘要: A subcritical multiplying assembly (SMA) was employed to improve the relatively low neutron fluxes of a 252 Cf source, and feasibility using it as source for boron capture therapy explored. The Monte Carlo code MCNP used evaluate effective multiplication factor k eff entire system, intensities percentages epithermal flux at patient-end surface beam, dosimetric properties beam in elliptical brain phantom. with SMA provides an ∼13.2 times higher than without SMA. After some optimization procedures, final design maximum advantage depth (AD) 8.9 cm, minimum AD 7.3 ratio 5.5, therapeutic relative biological effectiveness dose rate 4.23 cGy/min per 100 mg 7.0 cm This is ∼10 that provided by designed Therefore, expected can be more treatment tumors due increased rates.