Status Report on the Rapid Cycling Synchrotron

The Rapid Cycling Synchrotron (RCS), originally designed as an injection energy booster for the Zero Gradient Synchrotron (ZGS), operated under constraints imposed by ZGS operation until December 1979. Once these restraints were removed, the RCS made rapid strides toward its near term goals of 8 μA of protons for Argonne National Laboratory's Intense Pulsed Neutron Source program. Reliable 30 Hz operation was achieved in the spring of 1980 with beams as high as 2 × 1012 protons per pulse and weekly average intensities of over 6 μA on target. These gains resulted from better injection matching, more efficient RF turnon and dynamic chromaticity control. A high intensity small diameter synchrotron, such as the RCS, has special problems with loss control which dictate prudence during intensity improvement activities. The studies and equipment leading to the intensity gains are discussed.