A fast nuclear particle generator is described, useful for highly penetrating particle beam inspection equipment, that is capable of generating pulses of 5 ns or less, which pulses may comprise neutrons of various energies, gammas of various energies, or a mixture of neutron and gammas of various energies. The nuclear particle generator includes means for decelerating an incident swept beam so that nuclear particles are generated only during that small time interval that a beam strikes a target. This eliminates spurious background nuclear particle generation, and decreases beam dump cooling requirements.
STATEMENT REGARDING FEDERAL FUNDING
 This invention was made with U.S. Government support under Contract Number DE-AC02-05CH11231 between the U.S. Department of Energy and The Regents of the University of California for the management and operation of the Lawrence Berkeley National Laboratory. The U.S. Government has certain rights in this invention.