The high cost and large size of conventional accelerator technology has stimulated a search for new methods of accelerating particles. The objective of this research is to develop compact and efficient radiation sources for active interrogation of objects in order to detect nuclear materials. The approach will be to use radiation sources generated by high power laser produced particle beams. The intellectual merit of the project stems from the novel approach to particle beam generation involving the use of the large electrostatic fields generated by intense laser pulses within plasmas, which can be several orders of magnitude higher than those found in conventional accelerators. These fields are ideal for accelerating electron bunches to high energies over very short distances. In the proposed work, the 300 Terawatt laser facility at the University of Michigan will be used to generate Giga-electronvolt-range energy electron beams which will then be used to generate a high flux of highly directional gamma rays to be used for simultaneous radiography and active interrogation (gamma ray activation) of material. The production of very energetic proton beams from underdense targets will also be investigated which may allow more efficient production of pions and muons. This proposed research may lead to broader impacts since such beams will be of benefit for a wide range of research which presently relies on accelerator technology including biology, materials science and medicine. Both graduate and undergraduate students will participate in this work and efforts will be made to increase public understanding of laser and beam technology as well as to promote diversity.
