Microspec Neutron Probe


The MICROSPEC Neutron Probe (N-Probe) is a revolutionary portable neutron scintillation spectrometer, designed to be used by non-specialists for measurement of low-intensity neutron doses in the mixed field environments often found in nuclear utilities, fuel storage areas, fuel and waste processing operations and military applications. It is compatible with the current generation of MICROSPEC analyzers and shares the philosophy of spectral dosimetry with other BTI spectroscopic probes, where the dosimetric quantities are computed from the spectrum using appropriate fluence-dose conversion functions.

The N-Probe uses two separate detectors to cover the neutron energy range from thermal to 20 MeV. A liquid scintillator is used to cover from 800 keV to 20 MeV while a 3He proportional counter based on the 3He(n,p) T reaction is used to cover the energy region from thermal to 800 keV. Sophisticated pulse-shape discrimination circuitry distinguishes unwanted gamma-ray signals from the desired neutron signals. The two detectors work in unison and pulse-height distributions from both are shown during data collection. With one command from the keyboard, these distributions are merged and processed automatically to yield the desired neutron spectrum.

Technical Specifications

  • Analyzer Compatible with MICROSPEC analyzers
  • Detector Type Liquid scintillator and 3He counter
  • Spectral Range Thermal to 20 MeV
  • Size (without handle) 30.0 x 18.0 x 17.5 cm (11.8 x 7.1 x 6.9 in.)
  • Weight 4.1 kg (9.0 lbs)
  • Battery NiMH (runtime > 12 hrs)
  • Gamma Rejection Approximately 1000:1 @ 20 ºC
  • Dose Rate Range < 1 to 200 µSv/hr (< 0.1 to 20 mrem/hr)
  • Temperature (Operating/Storage) 5 ºC to + 40 ºC
  • Dose Conventions Kerma, Dose equivalent; (NCRP-38), Ambient dose equivalent [H*(10), ICRP-74]