An Epithermal Neutron Beam from the MURR and from an Accelerator Source Compared to the Beam at the BMRR

Abstract

An ideal neutron beam for BNCT is a beam of epithermal neutrons, forward directed, and free of gamma rays and thermal and fast neutrons. There are now two reactor-based epithermal beams1,2 in service in the USA and one in The Netherlands3. Several designs for reactor-and accelerator-based epithermal beams have been proposed. Of these neutron beams, three neutron beams have been selected, evaluated, and compared: (1) the operating Brookhaven Medical Research Reactor (BMRR) epithermal beam1, (2) the designed Missouri University Research Reactor (MURR) epithermal beam4, and (3) the accelerator-based epithermal neutron beam designed by Wu5. The horizontal sections of these three neutron beams are depicted in Figure 1 to Figure 3. Irradiation points for future reference are labelled as “Y” in each figure. These neutron beams are compared with respect to the neutron spectra, neutron and gamma fluxes and doses, and beam directionality.