Capture and containment of the positron beam in the APS injector linac

The authors describe the positron-capture solenoid and F0D0 system for the 450-MeV positron injector linac of the 7-GeV Advanced Photon Source (APS) storage ring at Argonne National Laboratory. A nonlinear beam optics study of the positron-capture solenoid following the positron converter is performed. Based upon an analytical expression of the magnetic fields, the phase space acceptance of the positron-capture solenoid is obtained. The detailed F0D0 structure of the positron-focusing quadrupoles is also discussed.<>