Compact electron‐accelerator system using laser‐induced photoelectrons and DISKTRON electrostatic accelerator

Abstract

A new type of relativistic electron acceleration facility is being developed by the Laser Science Research Group at The Institute of Physical and Chemical Research. It utilizes laser‐induced photoelectrons accelerated by a compact DISKTRON electrostatic accelerator, which makes it possible to generate a controllable bright short‐pulsed electron beam up to the energy of 1 MeV with a low emittance (<2×10−5 mrad) and high current density (∼500 A/cm2) without any guiding field. The characteristics of the entire facility and some of the key components are described in detail. The experimental results which confirm the possibilities of increasing quantum efficiency of metal photocathodes by geometric alteration are reported. Observation of laser undulator effects in the visible wavelength was demonstrated in the facility. The coming use of the system includes a far‐infrared/submillimeter free‐electron laser using a microwiggler and generation of extreme ultraviolet radiation by the laser undulator.