251th HiLumi WP2 Meeting

Tuesday 6 Oct 2026, 10:00 → 11:10 Europe/Zurich

Chair: Rogelio Tomas

Minutes: Guido Sterbini

10:00 → 10:10 General information & Introduction of the meeting

-HLMC attended by Nicolas

-Proposed dedicated calibration runs (for detector and machine) by Joachim:

https://docs.google.com/spreadsheets/d/1EV1LFmh_Zx_QK2V5FqjgzXCYhgkbKPBtRkikmlHBA8E/edit?usp=sharing

Hardest probably on the 5cm bunch length

-Discussions on the CC running mode for ions:
Option 1:
- RF on, fdbk on, tracking RF frequency through ramp with betatron comb off
- WP4 to check noise performance degradation with present technology (may take several months)
- WP2 to check how much margin do we have compared to protons factor xx during physics (to be confirmed). Additional noise acceptable during inj/ramp
- We assume RF noise independent of the voltage - WP4 can try to study this in SM18 in 2027

Option 2:

RF OFF
- RF off during injection/ramp. RF-ON with feedback and counter-phasing at flat top - frequency control during inj/ramp to be studied using beam induced voltage.
- RF off at all times and (maybe slightly detuned), frequency tuning only with beam induced voltage to be studied.
- WP2 will study impedance/stability aspects

-Discussions on interplay between single beam crabbing and full detuning

Speaker: Rogelio Tomas Garcia (CERN)

10:10 → 10:30 Performance with single beam crabbing option

Speaker: Sofia Kostoglou (CERN)

HLlumi_Run4_CC_1.pdf

HLlumi_Run4_CC_1.pptx

10:30 → 10:50 DA with single beam crabbing option

Speakers: Max Topp-Mugglestone, Dr Max Topp-Mugglestone (CERN)

20261002-DA-crab.pdf

20261002-DA-crab.pptx

10:50 → 10:55 AoB