We present new results on the neutron detection efficiency of detection systems based on He-3 proportional counters compared to organic liquid scintillators. The experiments were conducted using a well-characterized Cf-252 neutron source, measured bare, and shielded with slabs of polyethylene. The results show that the intrinsic neutron detection efficiency for the bare source is approximately 25% for the He-3 system, and 67% for the liquid scintillator system. When polyethylene sheets were used to shield the source in 2.54 cm increments, the neutron detection efficiency of both systems decreased exponentially to approximately 10% for the case of 25.4 cm. Experimental results were simulated using MCNPX-PoliMi and good agreement was found between measurement and simulation results for all the cases considered here.
Revised: June 17, 2020 |
Published: June 11, 2019
Citation
Pozzi S., S. Clarke, M. Paff, A. Di Fulvio, and R.T. Kouzes. 2019.Comparative Neutron Detection Efficiency in He-3 Proportional Counters and Liquid Scintillators.Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment 929.PNNL-SA-131452.doi:10.1016/j.nima.2019.03.027