A Monte Carlo study of ideal beams for epithermal neutron beam development for boron neutron capture therapy

A series of 'ideal neutron beam' studies has been carried out using Monte Carlo simulation with the goal of providing guidance for epithermal neutron beam design for boron neutron capture therapy (BNCT). An 'ideal beam' is defined as a monoenergetic, photon-free source of neutrons with user-specified size, shape and angular dependence of neutron current. Although discrete-energy, uncontaminated neutron sources are currently largely unobtainable, there are a number of computational techniques that allow simulation of such sources, thereby permitting an otherwise difficult or impossible investigation. For example, the Monte Carlo code MCNP has been used extensively in studies of beam design and dosimetry in neutron capture therapy; MCNP installed on SUN SPARC workstations in the Whitaker College Biomedical Imaging and Computation Laboratory at MIT was also used in the current study