Operation and Recent Developments of the Photon Factory Advanced Ring

The Photon Factory Advanced Ring (PF-AR) is a synchrotron light source dedicated to X-ray research. Although the PF-AR is usually operated at a stored beam energy of 6.5 GeV, a 5.0 GeV mode is also available for medical application. In the 6.5 GeV mode, the beam current of 60 mA in a single-bunch and the typical lifetime of 15 hrs at the current have been archived. Single-bunch operation for pulsed X-ray and its relatively high beam energy characterize the PF-AR. However, the high-current in single-bunch causes several problems to be solved, such as the temperature rise of some of the vacuum components, a pressure increase in the ring, and a sudden drop of beam lifetime. In order to avoid these problems, developments of new methods have been continued. In this paper, the status and the recent developments of the PF-AR are presented. It concerns: the successful operation with a two-bunch high-current operation at 5.0 GeV; the vertical beam size control for the medical application; modulating the RF acceleration phase in order to elongate the bunch length; stabilizing temperature in the ring tunnel; the study for medium emittance operation with 160 nm · rad; transferring the RF cavities in order to install a new insertion device; an innovative injection scheme using a pulsed quadrupole magnet.