The Multi-TeV colliders should have the capability to accelerate low emittance beam with high rf efficiency, X-band normal conducting high gradient accelerating structure is one of the promising candidate. However, the long range transverse wake field which can cause beam emittance dilution is one of the critical issues. We examined effectiveness of dipole mode damping in three kinds of X-band, π-mode standing wave structures at 11.424GHz with no detuning considered. They represent three damping schemes: damping with cylindrical iris slot, damping with choke cavity and damping with waveguide coupler. We try to reduce external Q factor below 20 in the first two dipole bands, which usually have very high (R/Q)T. The effect of damping on the acceleration mode is also discussed. Finally, I will show some of my work on wake field calculation for S-band disk loaded structure, thermal effect studies on power coupler for superconduting 9-cell cavity, etc..

Monday, August 17, 2009

3:30 p.m. - 4:30 p.m.
CEBAF Center, Room L102/104

Talk Slides: ((Slides)


Dr. Alex Bogacz or Anne-Marie Valente.