1. LARP-CM10, BNL 23-25 Feb., 2008 J. Byrd, Lawrence Berkeley National Laboratory LHC Crab Cavities: Proposed LBNL Contributions John Byrd

2. LARP-CM10, BNL 23-25 Feb., 2008 J. Byrd, Lawrence Berkeley National Laboratory LBNL Efforts Design of HOM/LOM couplers (D. Li) –Extensive Microwave Studio and MAFIA modeling –Possibility of experimental verification on low power prototypes RF Controls (J. Byrd) –Stabilized RF phase distribution (most useful for local scheme) –RF controller development Beam-beam simulations of crabbed beams (J. Qiang) –Strong-strong code to gauge benefit of various crabbing schemes –See J. Qiang’s talk from the AP session earlier today.

3. LARP-CM10, BNL 23-25 Feb., 2008 J. Byrd, Lawrence Berkeley National Laboratory HOM/LOM Coupling Recent progress…. –Squashed cavity Reduced magnetic field Degenerate mode separation –On-beam-pipe damping Simulation and experiment shows stub coupling promising. With an optimized stub length, get Qext~200 –On-cell damping Field enhancement acceptable Qext low to several tens Need to check multipacting –Multi-cell Cell-to-cell coupling studied 2-cell/4-cell structure Effort highly leveraged on existing programs

4. LARP-CM10, BNL 23-25 Feb., 2008 J. Byrd, Lawrence Berkeley National Laboratory RF controls Stabilized RF distribution –Uses interferometrically stabilized optical fiber to deliver ultrastable relative RF phase (<100 fsec) –Prototype tests at SLAC show stability of ~15 fsec over several weeks (<0.1 mrad@800 MHz) RF Controller –Based on long-term development –Integral to fiber phase distribution Work leveraged on existing development for light sources (LCLS, NSLS-II, Fermi@Elettra) ~15 fsec Jan 2008

5. LARP-CM10, BNL 23-25 Feb., 2008 J. Byrd, Lawrence Berkeley National Laboratory Funding requests Design of HOM/LOM couplers –$40k labor; $30k RF Controls –$40k Beam-beam simulations of crabbed beams –$10k Travel –$10k M&S (RF controls) –$10k Total request: $140k