Results of the Boeing pulse compression and energy recovery experiments

Abstract

This paper describes pulse compression and energy recovery experiments using an RF photocathode gun and injector accelerator at a fundamental RF of 433 MHz (1f) and a third-harmonic RF accelerator section operating at 1300 MHz (3f). For pulse compression, the 3f section is used both to program the energy slew and correct for RF-induced curvature in the electron beam micropulse which is subsequently compressed in a non-isochronous, three-dipole chicane. A compression factor of six has been obtained for a micropulse charge of 3 nC. Both the transverse and longitudinal emittances were measured for the compressed pulse. In the energy recovery experiment, the photocathode drive laser pulse is split into two pulses separated in time such that the resulting electron pulses are both accelerated by the 1f accelerator, while the 3f section simultaneously decelerates one pulse and accelerates the other. This is achieved by placing the two micropulses on either side of the zero crossing of the 3f RF waveform. The results of both experiments will be discussed.