The IEC as a complementary neutron source to Cf-252

Californium-252 (Cf-252) has been widely used as a laboratory neutron source for a broad range of research experiments and for neutron activation analysis. However, in some cases, problems with licensing, storage of the radioactive material, and shielding complicate its use. The inertial electrostatic confinement (IEC) device provides an alternative neutron source, which may be advantageous for such situations. In the IEC, deuteron ions are accelerated, producing fusion reactions as they react with a deuterium plasma target. Present devices offer 10(6) -10(7) 2.9-MeV D-D n/s during steady-state operation. Consequently, the IEC neutron source is currently competitive, in terms of neutron strength, with Cf-252 sources and offers a number of advantages, including an on-off capability, longer lifetime without deterioration in strength, and minimum radioactivity involvement. The IEC also offers the ability to convert to higher energy (14-MeV) neutrons by substituting D-T fill gas for pure deuterium fill gas. Due to the higher reaction cross-section, the source strength for the same size unit is increased to 10(8)-10(9) D-T n/s. For these reasons, the IEC provides an excellent laboratory neutron source far a variety of research projects. Two basic geometries have been developed-a spherical unit and a cylindrical unit. Spherical units, have vacuum vessel diameters ranging from 15 cm to 60 cm and have been operated, while current cylindrical units are approximately 12 cm in diameter by 1 m long. Currently smaller cylindrical designs are under development. Consequently, the spherical unit provides a ''point'' source of neutrons, while the cylindrical device provides line source.