W-band Sheet Beam Klystron Research at SLAC

SLAC is developing sheet beam klystron technology for narrow bandwidth, high peak and average power applications from L-band to W-band. Sheet beam devices are advantageous for several reasons. The primary advantage is the increased surface area in the RF circuit which significantly increases the dissipated heat that can be transferred through the circuit. The reduced charge density in the beam decreases the magnetic field required for beam transport and increases the achievable efficiency compared to a pencil-beam tube with the same beam voltage and current. Finally, both the RF circuit and the magnetic focusing system are simpler and less expensive to fabricate. The combination of features provided by a sheet beam klystron make it an ideal source for linear accelerator and high average power applications