An accelerator has limited dynamic range: a chain of accelerators is required
to reach high energy. A combination of septa and kicker magnets is frequently
used to inject and extract beam from each stage. The kicker magnets typically
produce rectangular field pulses with fast rise- and/or fall-times, however the
field strength is relatively low. To compensate for their relatively low field
strength, the kicker magnets are generally combined with electromagnetic septa.
The septa provide relatively strong field strength but are either DC or slow
pulsed. This paper discusses injection and extraction systems with particular
emphasis on the hardware required for the septa.Comment: 18 pages, presented at the CERN Accelerator School CAS 2009:
Specialised Course on Magnets, Bruges, 16-25 June 200