An Integral Experiment on Polyethylene Using Radiative Capture in Indium Foils in a High Flux D-D Neutron Generator

Abstract

We report here the results of a measurement of the scattered versus unscattered neutron fluence on polyethylene determined via neutron activation of multiple natural indium foils from a deuterium-deuterium (D-D) neutron generator. The neutrons were produced by the High Flux Neutron Generator (HFNG) at the University of California, Berkeley, a specially designed source to maximize neutron flux on a sample while minimizing the total neutron yield. During the experiment, approximately 10⁸ n/s were produced with the energies at the indium foils ranging from 2.2 to 2.8 MeV. Both the angle-integrated and the partial angle differential results are consistent with the predictions of the Monte Carlo N-Particle Transport (MCNP) code, using ENDF/B-VII.1. This supports shielding calculations in the fast energy region with high-density polyethylene.

Keywords:

• Cross sections
• nuclear data
• integral experiments
• neutron, polyethylene

Acknowledgments

This work was performed under the auspices of the U.S. Department of Energy U.S. Nuclear Data Program at Lawrence Berkeley National Laboratory under contract DE-AC02-05CH11231 and National Science Foundation grant EAR-0960138. The simulation used the Savio computational cluster resource provided by the Berkeley Research Computing program at the University of California, Berkeley.