LHC 2011 - latest news

Week 41: Machine coordinators: G. Arduini & J. Wenninger

Goal of the week: Luminosity production, MDs (pile-up, 25 ns)

 

Day

Summary

Link to report from morning meeting

Monday 17th October
  • 07:00 Dump fil #2219, 123 pb-1 delivered. New record.
 08:30 meeting

Sunday 16th October
  • Filling #2217: new filling scheme with main-satellite collisions in ALICE, 1% more collisions to ATLAS/CMS and 2% more to LHC.
  • •01:46 STABLE BEAMS #2217: 3.44x1033 cm-2s-1 with 1.4x1011 p/b (3.5x1033 cm-2s-1 seen during the adjust phase)
  • 02:55 Beams dumped by RF (HOM temperature): 13 pb-1 in ~1h
  • 05:30 back in physics (2:35 h turnaround – some delay to due to temperature on MKI8)
  • STABLE BEAMS #2218 3.49x1033 cm-2s-1 with 1.4x1011 p/b
  • 08:08 Beam dump due to power converter problem on RQT12.L5B2. End of fill #2218. 29 pb-1 in 2.5 hours.
  • 10:30-11:30 Access for power converter problem.
  • TDI moved to +- 55 mm after injection.
  • 15:30 STABLE BEAMS #2219 3.5x1033 cm-2s-1 with 1.4x1011 p/b
 09:00 meeting

Saturday 15th October
  • 00:30 -01:30 Injection steering for 50 ns beam
  • 03:00 Stable beam fill #2215, 3.2E33 cm-2s-1. High background in CMS due to vacuum R5.
  • 04:30 Dump, QS in RB 56 current lead. 15 pb-1.
  • 07:00 Injection
  • 09:30 Stable beams #2216, 3.3E33 cm-2s-1. New record intensity/stored energy at 3.5 TeV - 110 MJ.
  • 20:45 Trip of RQT12.L5B2. End of fill #2216. 92.5 pb-1 in ~11h
  • 22:30 - 00:30 Problem with TDI gap interlocks limits due to noise on the readings.
 09:00 meeting

Friday 14th October
  • 05:00 Beam dump due to trip of RQ5.R5 (likely SEU). ~50 pb-1 in 6 hours
  • 06:30 Access for QPS controller reset (MB.A9L5)
  • 10:30 Start of 25 ns MD.
  • 22:00 1092(B1)+1020 (B2) bunches at 25 ns circulating at 450 GeV
  • 23:15 end of 25 ns MD
 08:30 meeting

Thursday 13th October
  • 00:00-01:30 Injection corrections
  • 03:00 STABLE BEAMS #2208 Initial luminosity 3.3x1033 cm-2s-1
  • 13:00 TOTEM RPs moving into the beam.
  • 16:15: ADJUST mode. Test of ADT gain reduced up to 30% - OK.
  • 16:30 Beam dump by OP. collected 102 pb-1.
  • 17:30-18:30 access for nQPS reset (MB.B8R1). Delay due to biometry (SEU) and key distributor problem n UJ16 (SEU)
  • 20:30-21:30 Steering injection lines
  • 22:53 STABLE BEAMS #2210:  initial luminosity 3.48 x1033 cm-2s-1 with 1.35x1011 p/bunch
 8:30 meeting 

Wednesday 12th October
  • 00:00 Cryogenics recovered - Start precycle
  • 01:00-02:00 No beam from SPS (Main Power Supply problem)
  • 04:30 STABLE BEAMS #2204 - Initial luminosity 3.3x1033 cm-2s-1.
  • 09:30-10:15 Ramping ALICE down to 15'000 kA and back up.
  • 11:00 Move to ADJUST to switch on abort gap cleaning.
  • 11:30 Back to stable beams with abort gap cleaning on.
  • 16:30 Abort gap cleaning OFF
  • 17:30 Beam dump, vacuum Pt4. Integrated luminosity 95 pb-1. Manipulation on the BGI monitor induced a pressure spike.
  • 18:30 Access for QPS controller reset in point 5: MB8.L5
  • 20:00 - 24:00 Bad beam quality from the injectors:
    • RF synchro problem PSB-PS
    • Loss of the SPS kicker fine delays after create reboot

8:30 meeting

Tuesday 11th October
  • 03:30 Compressor restarted.
  • Cryo recovery. Urgent accesses.

8:30 meeting

Monday 10th October
  •  09:50 Beam dump fill 2200, IT L8 (PC). Integrated luminosity 44 pb-1.
  • Switching to MD on high pile-up.
  • Access for IT L8 PC.
  • 15:30Stable beams fill 2201, 5E30 cm-2s-1. 1 high intensity bunch per beam of 2.35E11 p/bunch. Pile up ~ 30-32.
  • 17:30 ALFA moving into the beam.
  • 19:20 End of fill #2201 for high pile-up study and ALFA data taking
  • 20:30: No beam from LINAC2 (buncher problem)
  • 22:30 Filling.
  • 23:40 Beam dumped during adjust. Lost cryo compressor in Pt6.PLC crash.

8:30 meeting