High-Temperature Highly-Efficient Ceramic Heat Exchanger

65691 Extremely bright, affordable, photocathode electron sources are required for future DOE facilities such as the Next Linear Collider and Next Generation Light Sources. An electron gun with greater than 1 nC per bunch and less than 1 p mm-mrad normalized transverse rms emittance would meet this need, but the sub 1 p mm-mrad target remains elusive. Because axisymmetry has been shown to be important for minimizing emittance growth, this project will develop an axisymmetric electron gun that optimizes the standard emittance-compensation technique to break the 1 p emittance barrier. Phase I will complete the radio frequency design of the emittance-compensated gun, conduct beam dynamics modeling to refine emittance compensation, and determine the expected performance of a complete injector system. A prototype gun will be fabricated and tested in Phase II. Commercial Applications and Other Benefits as described by awardee:The electron gun should serve as the injector for advanced, high-brightness X-ray sources for both medical and protein crystallography applications. In the medical market the ability of a monochromatic, tunable, x-ray source to deliver much clearer diagnostic images with a much smaller dose fraction would be extremely attractive for such applications as breast cancer screening. In the pharmaceutical and biomedical industries, a compact high-performance protein crystallography unit would find application in the production of ¿designer drugs¿ and in the ongoing task of mapping and DNA sequencing the human genome.