Meeting Notes

Present: Marlene, Patric, Justin, Daniel, Jim

MPP GWA Contract

• Contract is moving forward.

2. Beam Waist Measurement

2.1 Optical Method

• Manufacturer has no experience operating above 40 °C → lens will require cooling.

• Preliminary simulations indicate that adding the measurement system would impact temperature uniformity by approximately 1.5–2.5 °C on axis over ~10 cm (potential for improvement) on axis.

• Question: Can additional insulation be added to reduce thermal conductivity?

• Next step: Investigate relaxing the cooling requirement to approximately 35 °C.

Actions:

• Marlene & Patric: Study the impact of such a temperature dip on injection.

• Evaluate purchasing a lens and testing it under elevated temperature conditions.

2.2 Wire Scanner Method

• GWA identified a company capable of vapor-depositing a µm-width gold wire.

  • Open question: Could tungsten also be used?

• Glass coating could be an option, but thermal expansion may be problematic.

• PSI has an existing wire tensioning system.

  • Question: Would it function reliably in a higher-temperature environment?

Action:

• Patric to share a picture of the CLEAR cavity BPM.

Topics to Discuss with PSI

• Vibrations

• Feasibility and benefit of adding a third wire at 45°

• Possibility of using gold wire

• Whether only the fork of the wire system can be purchased

• How the tensioning system works and its compatibility with higher temperatures

• Required BPM location

3. Vacuum & Materials

Actions:

• Marlene to ask Maria Carmen about the upstream bypass volume.

  • Clarification: Flanges and connections to CERN VSC equipment will remain at room temperature.

• Marlene to ask Nicolas which material will be used for the spectrometer vacuum chamber and send the technical drawing to Daniel.

• Daniel to share magnetic permeability (µ) values of candidate materials for the large chamber.

• Afterward, Marlene to organize a meeting with Vittorio to follow up on mu-metal compatibility.

4. Beam Dynamics

• Aperture changes near the injection area require wakefield simulations of the full beamline (including injection region to the waist), or at minimum expert clearance.

Action:

• Marlene to ask Edda who will perform these simulations and request that this task be added.

5. Infrastructure

• GWA to provide rough estimates of heat dissipation from racks in TCV4.

• No temperature stability requirements currently specified for the racks.

Action:

• Patric to organize a meeting with Nicolas to discuss supports.

6. Next Meeting

Action:

• Justin to propose a date for the next in-person review.