Typically, sources of low energy neutrons are large and immobile, often filling entire rooms. A portable source of low energy neutrons would allow for accurate and safe detection of nuclear materials in the field.


The technology involves a portable source of low energy neutrons that can be transported easily to field sites, quickly set-up and operated to detect the presence of fissionable materials. The source makes use of low-voltage, pulsed-RF acceleration to obtain energetic particles useful in nuclear reactions that produce low energy neutrons. Small amounts of uranium respond strongly to low energy neutrons. Low energy consumption and small size (approximately the size of a standard refrigerator) make the unit portable. Standard electronics support the detection system.

  • Portable: Field operable
  • This neutron source provides more effective detection:
    • Reduced nuisance background
    • Low dose inspections with less than 10 milli-REM total fluence
    • Plastic or water shields can be identified
    • Does not cause secondary nuclear reactions
    • Penetration is effectively as deep as high energy sources
  • System components include simple threshold detectors
  • Safety: Lower radiation dose
  • Electrically generated: Source can be turned off
Potential Applications

Homeland Security: Field detection of nuclear fission materials (incoming cargo inspection)
Medical: Portable isotope creation for radiation therapy
Neutron Radiography: Non-destructive inspection on the manufacturing floor

Development Status

LLNL has demonstrated a prototype detection system built around the Low Energy, Portable Neutron Source technology. Small amounts of non-metallic uranium have been detected in minutes.

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