CeB6 electron gun for the soft X-ray FEL project at SPring-8

✍ Scribed by K Togawa; H Baba; K Onoe; T Inagaki; T Shintake; H Matsumoto

• Publisher: Elsevier Science
• Year: 2004
• Tongue: English
• Weight: 403 KB
• Volume: 528
• Category: Article
• ISSN: 0168-9002
• DOI: 10.1016/j.nima.2004.04.077

✦ Synopsis

A pulsed high-voltage electron gun with a thermionic cathode is under development for the injector system of the soft X-ray FEL project at SPring-8 (SCSS project). A CeB 6 single crystal of 3 mm diameter was chosen as a thermionic cathode because of its excellent emission properties, i.e., high resistance against contamination, uniform emission density and smooth surface. The CeB 6 cathode can produce a 3 A beam with 2 ms FWHM. A gun voltage of À500 kV was chosen as a compromise between the need for controlling emittance growth and minimizing the risks of highvoltage arcing. We have constructed a 500 kV electron gun test stand and have begun performance tests. This paper describes the basic design and the current status of the hardware R&D on the CeB 6 gun.