RF feedback control systems of the J-PARC LINAC

The J-PARC 181-MeV proton linear accelerator (LINAC) was commissioned in October 2006. The RF sources of the LINAC consist of 4 solid-state amplifiers and 20 klystrons. In each RF source, the RF fields are controlled by a digital RF feedback (FB) system installed in a compact PCI (cPCI) in order to realize an accelerating field stability of plusmn1% in amplitude and plusmn1deg in phase. In this paper, the performance of the RF feedback control systems will be reported in detail.