Modulator For Klystron 5045

The first modulator for a forinjector klystron of VEPP -- 5 is being tested now in BINP in Novosibirsk. The forinjector of VEPP -- 5 will involve a 510 MeV Linac consisting of four accelerating modules. The Klystron 5045 manufactured at SLAC [1] was chosen to drive the accelerating modules. This paper presents a design and some testing results of this modulator. I. INTRODUCTION The modulator is a conventional line type modulator with some supplementary characteristics. A simplified electrical layout of this modulator is shown in Fig. 3. The voltage value in a filter capacitor CF is determined by a phase-control system with six SCRs. The CF charging current is limited by three 500#H inductors connected to the primary winding of the rectifier transformer. In addition, this system provides "soft-start" capability and fast protection. The PFN is resonantly charged through a charging high-voltage SCR-switch (HV-switch), a charging inductor, and de-spiking circuits. The resonant PFN charge..

Influence of the laser modes on the energy spread in photoemitted electron beams

none9The properties of a GaAs electron source have been investigated through experimental work. Laser excitation can generate abnormal energy distributions in the photoemittedelectronbeam. We demonstrate that lasermodes are responsible for such an anomalous spread, which can be prevented by using a single mode light source.noneA.V. ALEKSANDROV; R. CALABRESE; N.S. DIKANSKY; V. GUIDI; N.CH. KOT; V.I. KUDELAINEN; V.A. LEBEDEV; P.V. LOGACHOV; L. TECCHIOA. V., Aleksandrov; Calabrese, Roberto; N. S., Dikansky; Guidi, Vincenzo; Kot, N. C. H.; V. I., Kudelainen; V. A., Lebedev; P. V., Logachov; L., Tecchi

High performances from a GaAs photoemitter

This paper aims at collecting the experimental results we have obtained ahout a GaAs photocathode, activated in negative affinity condition by depositing a thin layer of caesium and oxygen al its surface

Low energy intense electron beams with extra-low energy spread

Maximum achievable intensity for lowenergyelectronbeams is a feature that is not very often compatible with lowenergyspread. We show that a proper choice of the source and the acceleration optics allows one to match them together. In this scheme, a GaAs photocathode excited by a single-mode infrared laser and adiabatic acceleration in fully magnetised optics enables the production of a low-energy-spreadelectronbeam with relatively high intensity. The technological problems associated with the method are discussed together with its limitations

Device For Electron Bunch Length Measurement In the Picosecond Region

We designed, created, and tested a device for measuring electron bunch length in the picosecond region. The basic idea behind the method is a circular scanning of the electron bunch in the rotating magnetic field of a TM110 rf cavity. As a result, the longitudinal position of the electrons is transformed into an angular position in a plane orthogonal to the axis. The resolution limit of the instrument is 4 ps (rms)