Title :
Multi-harmonic RF control system for J-PARC RCS
Author :
Tamura, Fumihiko ; Yamamoto, Masanobu ; Schnase, Alexander ; Ohmori, Chihiro ; Takagi, Akira ; Uesugi, Tomonori ; Yoshii, Masahito
Author_Institution :
Japan Atomic Energy Res. Inst., Tokai, Japan
Abstract :
The RF cavity of J-PARC Rapid Cycling Synchrotron (RCS) has a low Q value and a wide band which covers the frequency from the accelerating frequency to the second harmonic frequency. The cavity is driven by a composite signal of the fundamental RF and the second harmonic RF. The system acts as a bunch shaping system as well as an accelerating system. In this presentation, a multi-harmonic RF control system is studied. The signal processing is based on a combination of digital hardware like 16 bit multipliers, arithmetic units, and FPGAs with commercially available signal processors. The beam loading compensation is a critical issue because of the high beam-current in the ring. The RF feedforward compensation system is discussed. Also the stability is discussed under the beam feedback loops.
Keywords :
accelerator RF systems; accelerator cavities; accelerator control systems; beam handling techniques; linear accelerators; particle beam bunching; particle beam dynamics; proton accelerators; signal processing; synchrotrons; J-PARC RCS; J-PARC Rapid Cycling Synchrotron; RF cavity; RF feedforward compensation system; accelerating system; beam feedback loop stability; beam loading compensation; bunch shaping system; composite signal; digital hardware; high beam-current; multiharmonic RF control system; multipliers; second harmonic RF; second harmonic frequency; signal processing; Acceleration; Control systems; Digital arithmetic; Digital signal processing; Field programmable gate arrays; Hardware; RF signals; Radio frequency; Synchrotrons; Wideband;
Conference_Titel :
Particle Accelerator Conference, 2003. PAC 2003. Proceedings of the
Print_ISBN :
0-7803-7738-9
DOI :
10.1109/PAC.2003.1289657
