Position-Sensitive Detector in Neutron Tomography and Material Characterization

Position-sensitive detectors (PSDs) have been used in neutron tomography and nanostructural characterization of material using neutrons that scattered from a monochromator of highly oriented pyrolytic graphite type, placed directly in the neutron beam in the Small Angle Neutron Scattering (SANS) facility at the Malaysian Nuclear Agency. PSD uses the He-3(n,p) reaction to detect neutrons. Because of the He-3 high neutron cross section of 5333 b at 25.3 meV, a PSD is suitable for neutron detection across its axial direction at a low neutron flux of 10(3) cm(-2) s(-1). Because of its insensitivity toward gamma radiation, the signals from the PSD for real neutrons are relatively easy to analyze. This paper discusses the use of a PSD in neutron tomography and nanostructural characterization of material in the SANS facility at the Malaysian Nuclear Agency.