FNAL efforts on LHC Crab Cavity R&D (Proposals for R&D sub-tasks, resources and schedule) Nikolay Solyak

List of sub-tasks (Near term R&D plan) Cavity and HOM/input coupler Design –Requirements for CC parameters (from LHC beam dynamics) –Cavity optimization (Kick, R/Q, field enhancement, HOM analysis) –Finalize RF design for 2 types of CC: baseline racetrack cavity (global scheme) and alternative compact-mushroom cavity (local). –Multipactoring analysis. –Conceptual design of the HOM coupler (as part of cavity geometry) –Conceptual design of the input coupler –Tolerances analysis –Mechanical analysis (resonance frequencies, Lorentz detuning, stiffening, tuning, sensitivity to He pressure) –Thermal analysis of cavity and couplers –Review of different cavity/coupler designs __________________________________________________________ Milestone:FY08 - mid FY09 Resources ~ 0.4 FTE’s (mostly Fermilab support) Travel /collaboration meetings/ review ~ 15 k T

List of sub-tasks (cont.) Aids in the cavity fabrication (AES), treatment and related infrastructure -RF control / tuning at all stages of CC fabrication -Copper model bench testing and characterization (proof of the concept) -Eddy current scanning of Nb sheets for defects -Providing of niobium material for prototype (needs discussion with SRF FNAL projects) -Design/modification and fabrication of necessary tooling for cavity handling, BCP/EP, HPR and HT treatment in ANL/FNAL facilities ________________________________________________ Milestones: end FY08-FY09 Resources ~ 0.3 FTE’s Tooling and infrastructure ~ 50 k

List of sub-tasks (cont.) Cavity processing / tests -Multiple cavity treatment (BCP/EP, HT, HPR, etc.) collaboration with ANL ~ 40 k -Clean room assembly quality checks, leak check etc. -Modifications of VTS to adapt CC (couplers, flanges) -Related hardware (amplifiers, RF equipment, thermal sensors, engineering etc…) - 30 k -Extensive vertical high gradient tests in liquid helium ________________________________________ Milestones: FY09 (preparation) – mid FY10 Resources ~ 0.2 FTE’s Hardware/materials ~ 100 k

List of sub-tasks (cont.) Frequency tuner design/test (slow) -Requirements for the tuner -Mechanical Design -Fabrication -Tests at room temperature and in cold temp. (VTS) ____________________________________________ Milestones: mid FY09 – mid FY10 Resources ~ 0.2 FTE’s - design prototyping/fabrication ~ 20 k _____________________________________________ Optics - phase I Preparation for proof of principle experiments at CERN

List of sub-tasks (cont.) Cryostat (LHC cryostat – CC integration) –Fermilab FTE resources are very limited in FY08-09 for any cryostat design work but will provide –Expertise –review of existing LHC cryostat to host CC –For integration design work (cryostat modification for CC) or design of a new cryostat will require support from LARP program or other source (FY10) New SBIR (?) –()

FNAL possible participation in others sub- tasks (for discussion) CC dressed cavity tests in Horizontal cryostat (HTS) – if needed – FY10 Cavity dressing, magnetic shielding etc… –Expertise, review (AES SBIR project) LLRF –Expertise, requirements, analysis, software, hardware High power components (phase shifters etc…)

Long-term R&D efforts (phase II) Design/layout of the IR optics and requirements for CC in local crab scheme Design of CC with small transverse dimensions (mushroom and other exotic shapes) for the local crab scheme