A Large Aperture Pulsed Septum Magnet for Antiproton Injection into the CERN AC Ring

A new collector ring (AC) is being built around the existing Antiproton Accumulator (AA) machine in order to increase the accumulation rate of antiprotons [1]. A much larger fraction of the particles produced at an improved target station will be transported to AC with a new 3.5 GeV/c beam line. This increased flux will be injected using a large aperture pulsed septum magnet capable of handling the 240 ¿.mm.mrad transverse emittances. Because the antiproton beam traverses the septum gap in air no vacuum problems arise and consequently the magnet can be of simple, glued construction. The beam requirements together with some of the unusual engineering design features of the 1.6 m long, 1 Tesla curved septum magnet are discussed.