Comparison of neutron detection efficiency using a He-3 counter and a Boron-10 loaded liquid scintillator EJ309B5

Performance of a He-3 counter and a B-10 loaded liquid scintillator EJ309B5 has been studied in terms of neutron detection efficiency. The measurements were carried out in a mixed field of neutron and gamma radiation from an intense (~106 neutrons/s/47t) 252Cf source. The response of both detectors to background and high intensity gamma radiation (~100 μSv/h at a detector) from a 60Co source has been measured to establish background count rate and gamma rays cut-off point, respectively. A method to compare the performance of various neutron detectors for border monitoring was proposed. The analysis showed that the properties of a He-3 counter are significantly better than that of EJ309B5. However, it has been pointed out how to improve the performance of a liquid scintillator in order to fulfill standards for neutron detection at borders.