Pascal Balleyguier (CEA Bruyeres-le-Chatel), Ulrich Becker (CST Darmstadt)
In 1997, a cold model of a so-called optimized proton accelerating structure was measured. It turned out that predictions of RF losses in the region of coupling slots had been dramatically under-estimated by the simulation codes . Since that time, a study made on the IPHI RFQ pumping holes showed that the problem occurred when a surface current line runs along a sharp re-entrant corner. This suggested a new way to compute losses and lead to an improvement in the MAFIA post-processor. We tested this new tool on the Trispal cavity geometry: the Q-drop caused by coupling slots is now very close to experimental values.
 P.Balleyguier, 'Coupling Slots Measurements Against Simulation For Trispal Accelerating Cavities', Proc. Linac Conference, Chicago, 1998.
Comments or Questions to