1. Direct Waveguide Couplers for the LHC Crab Cavity G. Burt Lancaster University (but its really Bob Rimmer’s idea) (and Brian Rusnak suggested it independently as well)

2. UK Update CERN-Cockcroft MoU signed, including LHC Crab Cavities. PhD student (Ben Hall) was recruited to work on LHC Crab Cavity. FP7-EuCARD is progressing.

3. LOM/SOM couplers We need strong coupling so this will perturb the cavity fields. With a 2 cell cavity we have the problem that if the couplers are asymmetric then the LOM and SOM will be asymmetric. This can be fixed with a asymmetric cavity shape this this is probably not something we want to do. We also need to fit in input couplers and HOM couplers so symmetric LOM/SOM couplers is going to be difficult

4. Direct Waveguide coupling Connecting the LOM/SOM coupler directly on the cavity equator gives very strong coupling and doesn’t take up space on the beampipes.

5. Operating mode The fields of the operating mode are zero in the plane of the waveguide.

6. SOM Coupling with Direct WG External Q for both SOM’s is 18!!!!

7. LOM Coupling with Direct WG External Q for both LOM’s is 48!!!!

8. Alternative version of SLAC design It may be easier to manufacture a coaxial-to-waveguide coupler if the coaxial line is not attached to the beampipe. This will add stability issues but will be tuneable adding the ability to tune with the LOM coupler.