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In the development of high-power free-electron lasers, intense electron beams are required. Large area, directly heated lanthanum hexaboride cathodes have been proposed as the electron emitter. To aid in the design of the cathode, the resistivity of lanthanum hexaboride as a function of material density and temperature has been measured.

The paper presents the cooperative design efforts of LBL, LLNL and SLAC on the Magnet Power Conversion Systems for PEP-II. The systems include 900 channels of correction magnets bipolar power supplies and 400 unipolar power supplies in the range of 5 to 500 kW. We show the decision process and technical considerations influencing the choice of power supply technologies employed. We also show the development of specifications that take maximum advantage of both the available resources and existing facilities while, at the same time, satisfying tight constraints for cost control, scheduling and coordination of different working groups. Switchmode power conversion techniques will be used extensively in these systems, from the corrector supplies to the largest units if the dynamic performance specifications demand it. General systems descriptions for each of the power supply ranges and for a new common control systems interface are included.