C100 Refurbishment Brainstorming Arne Freyberger, Geoff Krafft, and Tony Reilly Also Contributing: G. Ciovati, Need More Contributions!
C100 Refurbishment C100 Refurbishment is now part of the CEBAF Performance Plan. Need to start the planning process now. Start with assembling a wish list. At this stage any input from any regular PIT attendee is welcome. Suggested initial organizing categories Measurements to be performed during disassembly Cavity (re)processing to be performed during refurbishment Best practices re-assembly procedures to apply Problems in current C100s "to fix“ Reliability improvements (methods to reduce trip/quench rates or FE) Additional important categories???
Measurements to be performed during disassembly Leak check both the insulating vacuum and the cavity string prior to disassembly to identify and replace faulty components. (Gigi) Examine internal and external probe cables for radiation damage (Hovater) (Go to SiO2?)
Cavity (re)processing to be performed Make Cavities Stiffer (Hovater, Drury, Powers) (10 and 20 Hz modes higher and lower their Q (Explicit Dampers (Powers)) Reduce Lorentz coefficient and Hz/Torr Rinsing or other processing to clean up FE (Drury)
Best practices re-assembly procedures to apply Apply LCLS II and recent C50 methods/processing leading to reduced FE (Drury)
Problems in current C100s "to fix" Tuner rework to improve mechanical response and get piezo update that works (Hovater) Cornell “elegant” piezo idea to incorporate (Rimmer)
Reliability improvements (methods to reduce trip/quench rates or FE) Cavity characterization should take into account actual linac conditions -actual operating temps in the linacs, actual cool down rate capabilities (Drury) Consider adding a foot in the center of the CM in order to suppress the 20 Hz beam mode. (Powers) Consider adding some damping to the cryo lines where they come into the CM. (Powers) Add bolt landing spots on the insulating vacuum vessel for the waveguide to insulating vacuum interconnecting struts. (Powers) Provide more steps per Hz on the tuner motor (gear box?) right now it is 9 micro steps to go from 5 degrees detuned to on tune. It would be nice if it were at least 100 microsteps. (Powers) Add locking nuts to the nonsupporting feet. Currently the flange above them moves 4 mils when someone pushes the insulating vessel latterally. (Powers)
SUMMARY Eventual goal: prioritized (in importance) list of items to be included in the C100 refurbishment plan