Status of the 6.5‐GeV Photon Factory Advanced Ring

The Photon Factory Advanced Ring (PF‐AR) is a 6.5‐GeV synchrotron light source at the High Energy Accelerator Research Organization (KEK). It can provide high‐flux hard X‐rays for such research as the materials science, structural biology and medical applications. The PF‐AR has five insertion devices including four in‐vacuum undulators. It is operated with a single bunch which fits for time‐resolved experiments. A special 5‐GeV operation is partly provided for a clinical application. An initial beam current and a beam lifetime are 60 mA and approximately 14 hours, respectively. Recent developments include an installation of a new in‐vacuum undulator (U♯NW14‐36) to the west rf section, which was accompanied by transferring two rf cavities to other section. The undulator has been successfully operated at a minimum magnetic gap of 10 mm. We also carried out such accelerator studies as a successful test of beam injection using a pulsed quadrupole magnet, a study of low emittance optics, an establishment of tw...