Accession Number : AD0649773

Title :   A METHOD OF EVALUATING FAST-NEUTRON DIFFERENTIAL SCATTERING CROSS SECTIONS WITH SHORT EXPERIMENTAL RUNS,

Corporate Author : OAK RIDGE NATIONAL LAB TENN

Personal Author(s) : Verbinski,V. V. ; Courtney,J. C. ; Betz,N.

Report Date : 28 FEB 1967

Pagination or Media Count : 36

Abstract : The method utilized a pulsed neutron source with a smooth, broad spectrum, making it possible to measure neutron scattering from 0.5 to 10 MeV in a single run of 1 to 2 hr duration for each scattering angle. Scattering samples of carbon, aluminum, iron, lithium hydride, and concrete about 5 cm in diameter were located about 1/3 meter from the pulsed neutron source, and neutrons scattered through an angle theta were directed down a 55-meter flight path to a liquid organic scintillator used to measure the time-of-flight spectrum of scattered neutrons. The energy-dependent neutron intensity thus obtained was compared with Monte Carlo calculations whose inputs were the measured neutron source term and neutron elastic, inelastic, and reaction cross sections compiled from the existing literature. The comparison provides direct corrections to the cross sections because single scattering is about ten times more probable than multiple scattering with the sample sizes chosen. This method provides an unambiguous check on the elastic differential scattering cross sections used as input for the Monte Carlo calculations, and good first-order corrections to these cross sections. (Author)

Descriptors :   (*NEUTRON SCATTERING, DIFFERENTIAL CROSS SECTIONS), FAST NEUTRONS, NEUTRON REACTIONS, CARBON, ALUMINUM, IRON, CONCRETE, LITHIUM COMPOUNDS, HYDRIDES, NEUTRON SPECTRUM, ELASTIC SCATTERING, MONTE CARLO METHOD, SHIELDING, DUCTS, REACTOR KINETICS

Subject Categories : Nuclear Radiation Shield, Protection & Safety
      Fission Reactor Physics
      Nuclear Physics & Elementary Particle Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE