A HIGH CURRENT HIGH BRIGHTNESS FERROELECTRIC ELECTRON SOURCE FOR ADVANCED ACCELERATOR APPLICATIONS

HIGH CURRENT HIGH BRIGHTNESS ELECTRON BEAM SOURCES ARE REQUIRED FOR ADVANCED ACCELERATOR APPLICATIONS WHICH INCLUDE ELECTRON GUNS FOR HIGH POWER MICROWAVE SOURCES, FLASH X-RAY SOURCES, AND INJECTORS FOR HIGH GRADIENT ACCELERATORS. PRESENT ELECTRON BEAM SOURCES SUCH AS THERMIONIC CATHODES, FIELD EMISSION CATHODES, AND PHOTOCATHODES, ARE EITHER INADEQUATE IN PERFORMANCE (SUCH AS IN BEAM QUALITY, CURRENT DENSITY, OR CURRENT UNIFORMITY) OR REQUIRE ULTRAHIGH VACUUM SYSTEMS OR EXPENSIVE AND COMPLEX LASER SYSTEMS. IN THIS PROJECT A HIGH CURRENT, HIGH BRIGHTNESS CATHODE BASED ON EMISSION FROM FERROELECTRIC MATERIALS WILL BE DEVELOPED. FERROELECTRIC CATHODES OPERATE AT ROOM TEMPERATURE USING SPONTANEOUSLY POLARIZED MATERIALS SUCH AS LEAD TITANATE-ZIRCONATE. PREVIOUS RESEARCH HAS DEMONSTRATED THAT THESE CATHODES PRODUCE HIGH CURRENT DENSITY, HIGH QUALITY ELECTRON BEAMS. ELECTRON EMISSION OCCURS UPON POLARIZATION CHANGE INDUCED BY A FAST ( 20 KV/CM) PULSE APPLIED TO THE MATERIAL. PREVIOUS RESEARCH HAS INDICATED HIGH BRIGHTNESS (>10(11) A/M(2)RAD(2)) PERFORMANCE OPERATING AT PRESSURES AS HIGH AS 10(-3) TORR. ROOM TEMPERATURE EMISSION OF ELECTRONS COMBINED WITH HIGH CURRENT CAPABILITY AND HIGH CURRENT DENSITY (POSSIBLY EXCEEDING 100 A/CM(2)) MAY ALLOW BEAMS WITH BRIGHTNESS >10(12) A/M(2)RAD(2), WHICH IS SUPERIOR TO BEAMS FROM PHOTOCATHODES. DURING PHASE I, THE DESIGN, FABRICATION, AND TESTING OF THE FERROELECTRIC CATHODES CAPABLE OF PRODUCING HIGH BRIGHTNESS BEAMS WILL BE CARRIED OUT. DURING PHASE II, A PROTOTYPE HIGH VOLTAGE ELECTRON GUN FOR COMMERCIAL APPLICATIONS WIL BE BUILT AND TESTED AT HIGH REPETITION RATES. THE DEVICE WILL BE DEVELOPED FOR INDUSTRIAL AND SCIENTIFIC APPLICATIONS.