A plasma focus is an rz-plasma pinch device that may preferentially produce either x-rays or neutrons. In its neutron-production mode, the neutron pulse duration is approximately 1012 neutrons/pulse from the d(d,n)3He(dd) reaction. The equivalent neutron yield form the d(t,n)4He(dt) reaction is approximately 1014 neutrons/pulse. The smallest plasma focus devices have produced approximately 107 neutrons/pulse from the (dd) reaction. Across this range of neutron yields, there are several applications for which the plasma focus seems to be well suited. With a total yield of approximately 1012 neutrons/pulse from the (dd) reaction, static neutron radiography for inert objects has been demonstrated. For biological systems, (dt) reaction yields of about 1012 to 1013 neutrons/pulse will produce acceptable neutron radiographs. Given the short duration of the neutron pulse and localized nature, (dt) neutron yields in the range of 1013 to 1014 neutrons/pulse provide a useful source for basic neutron physics studies. Finally, modest scaling of the plasma focus neutron yield to the range of 1015 to 1016 neutrons/pulse from the (dt) reaction may provide a method of producing some neutron-produced, medical radioisotopes.
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