1. CLIC Main linac structure and Crab cavity Vasim Khan 28.08.09

2. In order to damp the LOM & SOM the cut-off frequency of the manifold should be below 8.0 GHz which is the lowest mode in the cavity. Circular wave-guide Rectangular wave-guide TE 11 mode Fc= 7.63 GHz @ b= 11.5 mm TM 11 mode Fc= 7.62 GHz @ a = 30 x 26 mm x mm To damp the HOMs the cut-off frequency of the manifold should be above 12 GHz TE 11 mode Fc= 13 GHz @ b = 6.75 mm TM 11 mode Fc= 13.6 GHz @ 17 x 15 mm x mm TM mn TE mn

3. TM 01 Fundamental mode 8.0 GHz TM 11 Dipole (SOM) mode 12.0 GHz TM 11 TE 11

4. Crab cavity profile

5. Blue : H-H boundary condition Red : E-H boundary condition

6. 90 deg. 1s t mode 8.56 GHz TM01 180 deg. 3 rd mode 18.66 GHz 163 deg. 2 nd mode 15.56 GHz First 5 modes @ 120 deg. H-B.C. E-field H-field

7. 120 deg. 1 st mode 11.98 GHz TM11 180 deg. 2 nd mode 18.65 GHz TM11 180 deg. 3 rd mode 18.68 GHz TE11 First 5 modes @ 120 deg. H-B.C. E-B.C. E-field H-field

8. H-H B.C.E-H B.C. H-E B.C. SiC Simulation with SiC

9. SiC E-H B.C. H-E B.C. Simulation with SiC

10. Large coupling & no SiC H-B.C. Mode 1 Mode 2 Mode 3 Mode 1 Mode 2 Mode 3 E-field H-field

11. H-B.C. E-B.C. Mode 1 Mode 2 Mode 3 Mode 1 Mode 2 Mode 3 Large coupling & no SiC E-field H-field

12. E-B.C. H-B.C. Mode 1 Mode 2 Mode 3 Mode 1 Mode 2 Mode 3 Large coupling & no SiC E-field H-field

13. Cell # 21 Cell # 1 Monopole mode

14. Cell # 1 Cell # 5 Cell # 13 Cell # 24 Cell # 1 Cell # 5 Cell # 13 Cell # 24 Kick-factor calculations

15. Kick factor calculations ?? Monopole : Dipole : Does it depend on the group velocity? i.e. Whether it is negative or positive ?

16. Next ?? More simulations for the Crab cavity to optimise the dimensions, study dispersion curves. Simulations incorporating both circular manifolds Verification of kick-factor calculations (Bane & Gluckstern paper) CLIC_DDS : Simulations to verify the prediction of the fits Background reading for corrections in chapter #1 and necessary corrections. Issue(s) My passport has arrived in Manchester today....I assume I got visa, need to check this evening. For extending visa, I need to know the process!