Minutes and Summary

Main purpose of the meeting: Follow-up from joint accelerator workshop

1) Introduction (Brian)

Main points from the Joint Accelerator Performance workshop last week:

- on the injector side (booster, PS), things are looking good.

- on the SPS: possible limitations from vacuum activity and heating.

Pressure spikes in MKDH: limited bunch length at high intensity.

8b4e beams limited by vacuum, spikes in 800MhZ RF cavity

- heat load from e-cloud in the arcs main limitation for pushing # bunches and intensity

Do not expect much better conditions in 2023.

- to push intensity, need to insert gaps in trains. Hybrid scheme with 8b4e and 3x48b reduces heat load by 15%.

Not quite enough to get to 1.8x10^11 ppb. Will likely need hybrid with 36b batches. This should allow intensities till 2.0x10^11 ppb.

- other limitations: beam dump limits, mainly limited by TCDS (24b could help?).

RF should be able to handle all beams up to 1.8x10^11 ppb. MKI temperature to be monitored.

- most likely longer bunch lengths next year: ~1.2ns next year.

- 2023 optics were validated during MDs.

Expected fill evolution on slide 8.

Comment from Stephane:

- beta*=24cm with flat optics is more beneficial than round optics, but still to be finalized.

Q from Jorg:

can we have the luminous region plots with these parameters (slide 8, left)?

Filling scheme options on slide 9/10.

Hybrid scheme with 36b main candidate for 2023.

Moving 8b4e to end of train would give more flexibility. Possible in SPS?

Speculative: 24 bunches with 4e?

Luminosity comparisons in different schemes: slide 11.

Target for 2023: hybrid 36b with PU=60, with 1.8x10^11 ppb: this would give a 15% gain wrt. 2022. Numbers to be taken with care.

Sofia’s simulations on slide 12: fair agreement.

Schedule for 2023 now approved in RB, see slide 13.

Next meeting: January 16th.

Input to Chamonix workshop welcome!

Planned YETS activities on slide 3.

Would like to measure the new beamspot position with injection energy collisions as soon as possible.

Discussions ongoing on the preferred mu to be used in 2023. Default is 60, but 65 and 70 are being studied.

High beta runs: would prefer a few weeks between 90m and 3/6km run.

Need 2023 expected luminous region as input to MC simulation.

Suggest a meeting to discuss the ADJUST handshake procedure during YETS.