LHC 2011 - latest news

Week 27: Machine coordinators: Mike Lamont, Barbara Holzer (Saturday, Sunday only)

Major power cut 11:30 Sunday 10th July. Serious knock-on effects across accelerator complex. LHC cryogenics should be back late Monday/early Tuesday. Atlas and CMS solenoids not back until Thursday at earliest.

Planning - after recovery

1. Verification tests:
   1. TCDQ and TCSG relative position --> re-measurement required.
   2. Beam presence flag intensity limit
   3. Beam Dump (inject and dump mode)
   4. Asynchronous dump 450 GeV B2 (pilot or 1-2 nominal bunches)
2. Pilot + 2 nominal bunches (ATLAS needs the pilot on pilot collisions --> no overinjection)
   1. loss maps at injection
   2. 1 hour in stable beams
   3. loss maps at 3.5 TeV
3. 48 bunches per beam
   •  new fill pattern for satellite on main collisions in ALICE: pilot over-injected, 250ns SPS gaps
   • MKI pulse length might need increasing
   • keep in stable beams for 3-4 hours (check with experiments)
4. Default is to continue with the satellite collision scheme (unless requested otherwise by ALICE):
   1. 50ns_264b_249_0_240_36bpi8inj (1 fill)
   2. 50ns_840b_807_0_816_108bpi12inj (1 fill)
   3. 50ns_1380b_1331_0_1320_144bpi12inj.txt (luminosity production)

LHC coordination vistar

Day	Summary	Link to report from morning meeting
Monday 11th July	Recovery still on-going	8:30 meeting Power cut (Francois Duval) Cryo intervention during TS (Serge Claudet)
Sunday, 10^th July	11:30 Major power cut with knock-on effects across the CERN complex Cryogenics estimated to be back late Monday/early Tuesday	09:00 meeting
Saturday, 9^th July	08:00 cryo back & stable, machine cold, QPS problem in 81, expert studying the problem	09:00 meeting
Monday, 4^th July	06:00 Start of Technical Stop	08:30 meeting MD report