MEASUREMENTS OF THE NEUTRON ANGULAR FLUX SPECTRUM IN GRAPHITE
Abstract
Measurements of the neutron angular flux spectrum in graphite have been made to provide a standard of comparison for neutron penetration calculations. The configuration approximated a point, fission-like source in an infinite medium. The spectrum from 0.002 eV to 15 MeV was measured with an accuracy of plus or minus 10% to plus or minus 20%, and resolution of approx. 10%, by the pulsed-source, time-of-flight method. The source spectrum and other characteristics were also measured. Spectra were obtained at angles from 0 to 60 deg. and penetrations to 66 cm. In addition, dieaway measurements, indium subcadmium and epicadmium flux traverses, sulfur and aluminum threshold foil traverses, and a threshold foil spectrum measurement were made. Procedures, apparatus, and results are described in detail so that others can evaluate our results and use them to test transport codes and input approximations. Comparison of the time-of-flight data with a preliminary discrete-ordinates calculation indicates fairly good agreement except for detail in the carbon resonance region, where the flux oscillates strongly. Both calculations and experiment indicate the intermediate spectrum for r > 20 cm from the source is not 1/E as usually assumed. Low energy foil activation and time-of-flight results are consistent, but threshold foils give poor results.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 30, 1966
- Accession Number
- AD0664790
Entities
People
- A. E. Profio
- H. M. Antunez
- T. G. Williamson
Organizations
- General Dynamics