Radio Frequency (RF) systems at the SSRF comprise the normal-conducting RF system for the 3.5 GeV booster

and superconducting RF system for the 3.5 GeV storage ring. The normal-conducting RF system includes two 5-cell

copper cavities resonant at 499.65 MHz with RF power generated from a 180 kW klystron. After August 2014, the

RF amplitude stability and phase stability, which are controlled by low level RF (LLRF) controller based on digital

technology, are better than ±0.5% and ±0.5°, respectively. The superconducting RF (SRF) system consists of

three RF stations, and each RF station is composed of the SRF module, the 310 kW transmitters, the digital LLRF

control and the RF PLC interlock. It can provide total accelerating voltage higher than 4.5 MV with amplitude

stability better than ±1% and phase stability better than ±1° under the digital LLRF control. The SSRF currently

operates in top-up mode with a beam current of 240 mA. The RF parameters of booster normal conducting RF

system and of storage ring SRF system are listed in Table 1 and Table 2, respectively.

Table 1 Operation parameters of booster normal conducting RF system

Table 2 Operation parameters of storage ring superconducting RF system

The booster normal conducting RF system is operated at its design value to ramp the electron energy to 3.5 GeV. The system has been in stability operations at the SSRF since 2007. The storage ring superconducting RF system is operated to supply a little higher total voltages and more RF power to support the top-up mode at 240 mA beam current. Regular RF conditioning should be carried out to improve the stability and reliability of SRF system in the future regardless of the increasing beam time requests of users. The real-time RF data is showed in this web.

The RF group is responsible for the operation and maintenance of booster and storage ring RF system at the SSRF. Furthermore, the in-house development of superconducting modules including 500 MHz cavity and 1500 MHz harmonic cavity, and digital low level RF controllers is a great challenge for the RF group.

 The group is currently composed of 13 members.