CERN Accelerating science

Article
Title	Development of an Ultra Stable Klystron-Modulator for PAL XFEL
Author(s)	Oh, J S ; Jang, S D ; Ko, I S ; Kwon, S J ; Namkung, W ; Son, Y G ; Suh, J H
Affiliation	(PAL, Pohang, Kyungbuk)
Publication	2005
In:	27th International Conference on Free Electron Lasers, Palo Alto, CA, USA, 21 - 26 Aug 2005, pp.157
Subject category	Accelerators and Storage Rings
Abstract	The PAL (Pohang Accelerator Laboratory) is persuading to construct a SASE-XFEL facility (PAL XFEL) that supplies coherent X-rays. The bright and stable electron beam is essential for the PAL XEL. The electron beams has to have an emittance of 1.2 mm-mrad, a peak current of 3.5 kA, and a low energy spread of 0.5 MeV. In order to provide reasonably stable SASE output, the RF stability of 0.02% rms is required for both RF phase and amplitude. This is a technologically challenging issue for PAL XFEL. An inverter technology is to be applied to charge the PFN of a new modulator. Therefore, a new inverter system should provide very stable charging performances. This paper presents the development of an ultra stable klystron-modulator with an inverter power supply.