Minutes and Summary
Main purpose of the meeting:
Discussions on the LHC schedule for 2022
1) Introduction (Brian)
Topic of today: post-TS1 scheduling.
Keep on meeting every week for now.
Earliest possible start around Sept. 17, latest estimate Sept. 25.
Matteo estimates sometime in week 38. So that would leave 6 weeks till TS2, not 7.
List of post-TS1activities on slide 6.
The ion optics set up, which originally scheduled before TS2, is not scheduled after.
The schedule constraints are mention on slide 7.
Witold: ATLAS calorimeter calibration transfer fill needs toroid on (!)
Post-TS2 activities on slide 8.
PbPb cycle setup, including ion optics commissioning, may need to be extended to 5 days.
Witold: pp reference run also needs VdM. Can happen with regular optics during SB. Will be included in the 6 days.
Various options in slide 10-14.
David Stickland: CMS is not ready to take VdM immediately after the TS1 as in the original schedule, due to the long stop.
Option 4:
Comment from TOTEM: problem for the detector that the VdM (in particular) has high lumi. It will fry the detector. Need it for ions.
Luminosity for the VdM to be estimated.
Comment from Valerie: there is a high mu component to the VdM programme.
TOTEM: possible option to put the high beta very early in 2023 (where CMS remains off until after the high beta run).
Gianni does not like this.
Comparison of options on slide 15.
Filling scheme for LHCf run on slide 16. Now including 2 non-colliding bunches for IP1/5.
Witold: there are rumours of EDF power cuts in December. Any comment?
Rende:
- from 15th of October there may be "net schredding”. Negotiations ongoing. Power cuts with short notice possible.
Discussions ongoing.
- anticipated YETS is also on the table. No decisions taken yet.
2) Round Table
ATLAS (Joerg)
option 4 preferred.
Proposal to split the VdM programme in 2 parts and put the items that are not affected by toroid-off in September.
slide 6:
Comment from JW: if calib transfer at the end, the low beta needs to be recommissioned.
Discussion on what is needed, from operation and MPP point of view.
Witold will check if the toroid on is really needed for calibration transfer scan. JW will check MPP requirements.
Preference to keep ion run and pp ref run together.
Summary on slide 9.
Slide 10:
JW: during LHCf is probably the best option.
ALFA preparation: to understand better.
Cavern access: w39 should be w38.
CMS (Gianni)
option 4 preferred.
CMS prefers pp ref close to HI period. Could it be splitted in 2 parts? 1 day with PU~ 10 would be enough.
Remaining days can be moved to 2023.
Witold: would bring extra overhead of 2 VdMs.
Sarah (ALICE): ALICE cannot take the pp ref run in 1 day.
Would like feedback about LHC ramp-up after TS1 to prepare the trigger menu.
PPS mini-alignment can happen with 3b recommissioning fill.
LHCf run: yes, beam can be separated in CMS and ATLAS, if lumi not too high.
ALICE (Sarah)
ZDC commissioning: in October, possibly during LHCf run. Few colliding bunches in P2 and magnets ++.
Need 4 weeks of pp data taking to finalize HI preparation.
Need 4 intensity scans (500 kHZ to 5 MHz) with one week in between each for analysis
pp ref run very early in 2023: no opposition.
Need to keep 5 days.
The question of merging the 2 pp ref runs in 2022 and 2023 is not addressed.
LHCb (Federico)
option 4 is preferred.
VELO closure is critical this year. Need it for trigger and offline processing as well.
Prefer VdM after TS2. If not option 4, will request to decouple from ATLAS/CMS VdM.
VELO (first) Partial Insertion needs to be done in working hours and needs at least a full week of data taking before (LHCf run with collisions in LHCb included)
VELO (final) Full Insertion needs at least one week from Partial Insertion
LHCb asks whether the high beta* run is needed in 2022
LHCb requests colliding bunched during the LHCf run
LHCb is neutral wrt to whether the pp reference run happens in 2022 or early 2023
LHCf (Lorenzo)
option 1 no longer preferred due to VdM limitation (since lumi precision would be worse than 3%)
option 4 is preferred (lumi precision of 3% should be achievable).
LHCf test beam period: 12-19 October.
LHCf and ZDC installation/removal can be done usually during working days (+ Saturday if required; Sunday is much more difficult)
Prefer not to have high luminosity operations while the detectors are in place
LHCf installation foreseen for September 12th (next Monday), so decision on LHCf run needed this week.
TOTEM
moving high beta* to early next year is not a problem. Only bad consequence is that T2 will not be available during ion run.
