Los Alamos National Laboratory Neutron Reference Field Characterization Studies
M.S. Gadd; T.D. McLean; D.T. Seagraves; R.H. Olsher; and M.W. Mallett (Los Alamos National Laboratory)
The Los Alamos National Laboratory (LANL) Health Physics Measurements group (HSR-4) has the equipment and expertise for the characterization of neutron reference fields in calibration facilities. Currently these capabilities include the determination of the neutron energy distribution, from thermal (0.025 eV) to 20 MeV, as well as the dose equivalent rate. In the near future the energy range will be extended to 10 GeV. The techniques employed include Monte Carlo calculations using the MCNPX code as well as measurements with a multi-sphere spectrometer (Bonner Spheres), ROSPEC, N-Probe, and thermoluminescent dosimeters (TLDs). Characterizations have been performed at five national laboratories (Los Alamos, Pacific Northwest, Brookhaven, Sandia, and Savanna River). In addition, these techniques can be employed in the characterization of neutron fields in the workplace, environment, and from critical assemblies. The methods employed will be presented here as well as some results from the characterization studies.