Feasibility Study of Neutron Production at SLRI Beam Test Facility

SLRI Beam Test Facility (SLRI-BTF) has been constructed in order to increase usage of the Siam Photo Source injector. SLRI-BTF aims to provide electron test beams for calibration and testing of high-energy particle detectors and diagnostic instrumentations. The test-beam energy varies from 40 MeV to 1.2 GeV with adjustable intensity from a few to several millions of electrons per repetition rate. Since the test-beam energy is sufficiently large, the electron test beam can be used to produce photoneutrons resulted from collision of high-energy electrons to metal targets. Similar to the electron test beams, this neutron source will be utilized for calibration and testing of neutron detectors and instrumentations. In this work, the neutron production and its angular dependence has been investigated using the PHITS simulation code. The results show that photoneutrons generated by collision of the high-energy electron beam on a tungsten target are in range of intermediate and fast neutrons or 0.01 - 10 MeV with peak contribution at 0.6 +/- 0.1 MeV and uniformly distributed in angular direction. For the primary beam of 10(8) electrons per spill at SLRI-BTF, the photoneutron flux is predicted to be around 50 neutrons/cm(2). Based on this study, the possibility to service a neutron source for users in the future will be determined further.