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Title: Fast Neutron Detection using Pixelated CdZnTe Spectrometers

One important important signature of special nuclear materials (SNM) are fast neutrons. Fast neutrons have a low natural background rate and readily penetrate high atomic number materials which easily shield gamma-ray signatures. Thus, fast neutrons provide a complementary signal to gamma rays for detecting shielded SNM. Scattering kinematics dictate that a large nucleus (such as Cd or Te) will recoil with small kinetic energy after an elastic collision with a fast neutron. Charge carrier recombination and quenching further reduce the recorded energy deposited. Thus, the energy threshold of CdZnTe detectors must be very low in order to sense the small signals from these recoils. Here, the threshold was reduced to less than 5 keVee to demonstrate that the 5.9 keV x-ray line from 55Fe could be separated from electronic noise. Elastic scattering neutron interactions were observed as small energy depositions (less than 20 keVee) using digitally-sampled pulse waveforms from pixelated CdZnTe detectors. Characteristic gamma-ray lines from inelastic neutron scattering were also observed.
ORCiD logo [1] ; ORCiD logo [1] ;  [1] ;  [1] ;  [2] ;  [1]
  1. Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Nuclear Engineering and Radiological Sciences
  2. Sandia National Lab. (SNL-CA), Livermore, CA (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 0018-9499; 653592; TRN: US1702180
Grant/Contract Number:
AC04-94AL85000; NA0003525
Accepted Manuscript
Journal Name:
IEEE Transactions on Nuclear Science
Additional Journal Information:
Journal Volume: 64; Journal Issue: 7; Journal ID: ISSN 0018-9499
Research Org:
Sandia National Lab. (SNL-CA), Livermore, CA (United States)
Sponsoring Org:
USDOE National Nuclear Security Administration (NNSA); National Science Foundation (NSF)
Country of Publication:
United States
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; gamma-ray spectrscopy; CdZnTe detectors; special nuclear materials monitoring; neutron detectors; low-energy threshold systems
OSTI Identifier: