Portable Spectroscopic Fast Neutron Probe and ³He Detector Dead-Time Measurements


This paper presents dead-time calculations for the Portable Spectroscopic Fast Neutron Probe (N-Probe) using a combination of the attenuation law, MCNP (Monte Carlo N-particle Code) simulations and the assumption of ideal paralyzing and non-paralyzing dead-time models. The N-Probe contains an NE-213 liquid scintillator detector and a spherical 3He detector. For the fast neutron probe, non-paralyzing dead-time values were higher than paralyzing dead-time values, as expected. Paralyzing dead-time was calculated to be 37.6 μs and non-paralyzing dead-time was calculated to be 43.7 μs for the N-Probe liquid scintillator detector. Dead-time value for Canberra 3He neutron detector (0.5NH1/1K) was also estimated using a combination of subcritical assembly measurements and MCNP simulations. The paralyzing dead-time was estimated to be 14.5 μs, and the non-paralyzing dead-time was estimated to be 16.4 μs for 3He gas filled detector. These results are consistent with the dead-time values reported for helium detectors.


Nuclear Engineering and Radiation Science

Keywords and Phrases

Gas detectors; Monte Carlo methods; Probes; Scintillation counters; Attenuation law; Dead time; Dead time measurement; Gas-filled detectors; Liquid scintillator detectors; MCNP simulations; Monte Carlo N particle code; Subcritical assembly; Neutrons; Dead-time calculations

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Article - Journal

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© 2016 Elsevier, All rights reserved.

Publication Date

01 Sep 2016