Design of Beam Bunching System for the Ion Storage Ring of RIKEN RI-Beam Factory Project

In the operation energy of the storage ring, the longitudinal space charge force is dominant over forces induced through the coupling impedances. It lengthens bunches of beams below the transition energy. Ion beams colliding with elec-tron beams are desirable to be bunched as short as the de-tectable collision section of length 0.4 m. Electron cooling is considered as a tool to help ion beams to bunch under RF-voltage applying. Results of a simulation of the bunch-ing are present. An RF cavity is presented for the bunching.