Separators for SLAC B-Factory

In order to separate the beams during injection, a closed vertical bump will be introduced in the B-Factory High Energy Ring (HER) using four dedicated, pulsed magnets. The design field in the magnets is Bo=660 G; the field integrals of the magnets are nominally: ∫Hdl=0.0450 T·m; ∫Hdl=0.0420 T·m; ∫Hdl=0.0756 T·m; ∫Hdl=0.0832 T·m. The magnet apertures are 15 cm horizontal along the field direction and 10 cm in the vertical direction. The beams will be separated with a rise time of about 200 ms at the end of a coast and brought back into collision within about I ms. A good-field-region of ±4.1 cm in the horizontal and ±2.1 cm in the vertical direction with field non-uniformity less than 0.2% is aimed for, and fast magnetic field switch-off even through the present steel vacuum pipe of about 4 mm thickness. A 15% variation in each magnet current is done with variable shunts to allow tuning of the bump for different lattice configurations. The magnets have to fit into the existing constrained space of the B-factory. The magnets have been made and tested successfully at BINP and at SLAC. The whole system including pulsed power supply and shunts were also tested successfully