A NEW THERMAL NEUTRON FLUX DENSITY STANDARD

Abstract

Six Am241-Be(alpha,n) neutron sources are arranged around the central circumfejence of a graphite cylinder 28 cm in diameter by 26.5 cm high. This assembly is surrounded by 10 cm of polyethylene. The graphite cylinder contains an accessible central cavity, 5 cm in diameter by 5 cm high, for the calibration of thermal neutron detectors. The thermal neutron flux density in the cavity is measured by 4 pi beta-gamma coincidence counting of irradiated gold foils. A flux density below cadmium cutoff of nthvo= 8700/sq cm/sec (=1.5%) was found. The uniformity is shown to be constant within the cavity to better than =0.5% over a cylindrical volume 5 cm in diameter by 2 cm high.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Jan 30, 1964
Accession Number
AD0445239

Entities

People

  • C. K. Hargrove
  • K. W. Geiger

Organizations

  • National Research Council Canada

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Assembly
  • Calibration
  • Coincidence Counting
  • Detectors
  • Diameters
  • Dielectric Polymers
  • Flux Density
  • Geometry
  • Graphitic Materials
  • Materials
  • Measurement
  • Neutron Detectors
  • Neutron Flux
  • Neutrons
  • Nuclear Radiation
  • Radiation
  • Thermal Neutrons

Fields of Study

  • Physics

Readers

  • Electrical Engineering
  • Nuclear and Radiation Engineering.
  • Pulsed Power and Plasma Physics.