Jan 30 2024

Actually, Jan 31.

Action items from last time

• Carlos will develop a high-level timeline for the rest of the project.
• Now that the simulation models are working well, Max and Gabriel will optimize
  • the Pierce angle to give R28-like optics as a baseline and
  • the junction angle to allow for a larger lip radius, and less field enhancement. Carlos does not insist on the steep angle of R30-3, it can be a smooth transition.
• We will make two electrodes to have a spare; one can consider making two different shapes as a contingency plan. Carlos will ask Keith to join the meetings.
• Max will consolidate the set of field maps for apples/apples comparison in Alicia's injector model. Alicia will make a comparison between the updated R28, R30-3, and R30-4 models and work toward defining an acceptance band for phase-space parameters at the match point.
  

Updates and discussion

• Link to schedule SharepointLink to schedule in Sharepoint
• Keith Harding reports it will take him ~ 3 days to modify the existing R30-3 Pierce front-end piece and make TWO new models per Max's design. Carlos told Keith the following parameters will change from the original R30-3 drawing:
  
  • Hole diameter
  • Pierce angle
  • Junction angle
  • Lip radius
• Carlos sent the barrel polishing technote to Jessica and Chris Dreyfuss (he is in charge of the SRF tumbler polisher). The three met and discussed a plan to practice polishing a test piece to be ready when the actual pieces come from the machine shop.
• Max and Gabriel: CST model gives believable results, no remaining mysteries between CST and Poisson. Simulation results for different parameters...
  • Beam envelopes for 15,16,17,18 degrees Pierce angle
  • Focal length vs spot position
• Measured aberration of large-active-area gun in qualitative agreement with model, albeit focal length shorter overall... Data to be shown later.

Conclusions, path forward

• Deadline to define Pierce angle: Wednesday, February 7, 2024.Max, Alicia.
• Deadline to provide Keith Harding with the chosen models (TWO Pierce angle options): Friday, February 9, 2024.Max, Gabriel:
• February 13, 2024. Present before the B-Team meeting the strategy followed for arriving at the optimized Pierce angle. Max and Alicia.
• Enter here additional input from the meeting

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