Pulsed Magnet Injection for the MAX IV 3 GeV Storage Ring
Last revised: June 12, 2012
Author: Simon C. Leemann
This report investigates the use of a pulsed magnet for injection into the MAX IV 3 GeV storage ring. Such an injection would not require a local injection bump and thus avoid the alignment and synchronization issues associated with the four kickers and pulsers used in conventional injection schemes. The note starts off with a few theoretical considerations and proceeds to demonstrate the feasibility of injection into the 3 GeV storage ring with a single pulsed sextupole. The conclusion is that a pulsed sextupole (half-sine pulse with base τ = 3.5 μs) with an integrated strength of (b3L) ≈ 54 m−2 installed at end of the long straight following the injection straight is adequate for injecting into the 3 GeV storage ring. Alternatively, two- turn injection (half-cosine pulse with base τ = 7 μs) with an integrated strength of (b3L) ≈ 28 m−2 can be applied. Such an injection should be transparent to the beamlines. Hence, frequent low-charge top-up shots become possible allowing for almost perfectly constant stored current in the machine.