THE PHYSICS AND SHIELDING ASPECTS OF HETEROGENEOUS ISOTOPIC NEUTRON SOURCES,

Abstract

This study is concerned with the feasibility of constructing an isotopic neutron source which has the characteristic that it can be turned on or off at the option of the user. The alpha-neutron reaction was selected to be the source of neutrons. It was desired that a suitable combination of radioisotope material and target material be selected which exhibited a high neutron yield when the two materials were placed into the on mode, and yet exhibited low radiation intensities when the source was in the off mode. This way, a compace source of high intensity would be possible which would require little or no shielding when not in use. Source half-life, material availability and cost were considered. It was concluded that two radioactive materials, polonium-210 and plutonium-238, appeared to be the most attractive radioisotope materials. For a mechanical on-off system, beryllium was considered to be the best target material since it exhibits the highest yield in an alpha-neutron reaction. Typical neutron energy spectra and neutron yeilds were calculated which showed that the ratio of neutrons emitted while in the on mode compared to the off mode was on the order of 10,000. Calculations were made of neutron and gamma ray intensities.

Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1965
Accession Number
AD0625406

Entities

People

  • Donald F. Knuth

Organizations

  • The Catholic University of America

Tags

DTIC Thesaurus Topics

  • Absorbers (Materials)
  • Actinides
  • Advanced Materials
  • Availability
  • Beryllium
  • Elements
  • Engineered Materials
  • Gamma Rays
  • Intensity
  • Isotopes
  • Materials
  • Neutron Reactions
  • Plutonium
  • Radiation
  • Radioactive Materials
  • Shielding

Fields of Study

  • Physics

Readers

  • Nuclear and Radiation Engineering.
  • Systems Analysis and Design