LHC 2011 - latest news

Week 24: Machine coordinators: Gianluigi Arduini, Bernhard Holzer

Goals of the week: Luminosity production

LHC coordination vistar

 

Day

Summary

Link to report from morning meeting

Monday, 20th June
  • Cryo recovery
08:30 meeting
Sunday, 19th June
  • Cryo recovery ongoing
  • Morning and afternoon: extraction tests to the first TED and to the second TED for investigations on trajectory stability in TI2
  • Test of the BIS loops for 2 hours ==> no remaining problem observed.
09:00 meeting
Saturday, 18th June
  • 00:01h erratic injection oscillations in both beams, reason not known, optimisation difficult
  • 05:02h injection completed, start ramp
  • 05:07h again dump due to BIC
  • 07:00h injection, ramp, squeeze, lumi: stable beams
  • 07:48h beam dump: BIC spurious interlock
  • 08:30h access BIC repair
  • 13:00 Intervention on BIC finished (replacement of optical fiber receiver in point 8)
  • 13:00-15:00 Large emittance beam in the SPS. Tuning of the machine
  • 15:00-17:00: check of injection
  • 17:00: Cryo problem in point 8

09:00 meeting

Friday, 17th June
  • 01:13h stable beams #1873. Initial luminosity ~1.1×1033 cm-2s-1 ,  Longer time spent at injection due to inequalities in bunch intensity
  • 02:06h Beam dump. Spurious trigger. End of physics #1873. ~3 pb-1 in 50 min
  • Fill #1874 lost due to RQTF.A78B1 trip at the beginning of the squeeze (QPS trigger)
  • 06:15h stable beams #1875. Initial luminosity ~1.05×1033 cm-2s-1
  • 08:30h van der Meer scan in IP5, afterwards: stable beams
  • 14:04h beam loss, integrated lumi: 25.3 pb-1 , dump due to orbit excursion, reason unclear, in coincidence trip of undulator and according loss of cryo in L4 and loss of the60 A circuits in sector 12
  • access for RF (coupler) and QPS (check undulator QPS)
  • connect rf coupler alarms to the LHC dump system and test it
  • 18:00h precycle for restart
  • 19:00h injection, ADT problem (HV)
  • 22:00h IQC cash not working
  • 24:00h HV trip of RF klystrons (klysrton 6b1 has to be kept switched off)
08:30 meeting
RF beam interlocks (A. Butterworth)
Thursday, 16th June
  • 00:00h injection for physics
  • 03:12h beam lost on ramp: UFO
  • 04:36h injection, ramp, squeeze
  • 07:20h stable beams #1872. Initial luminosity 1.1x1033 cm-2s-1.
  • 14:50 Trip of Sector 81 (new QPS - QF- B11.R8). End of physics #1872. ~22 pb-1 in 7.5 h. >1 fb-1 delivered in 2011 at 3.5 TeV
  • 15:00 - 18:00 Access for QPS reset in Sector 12 and for RF in point 4. Intervention on BIW in point 5. Access for LHCb.
  • 19:00-21:00- 2nd access for QPS required because of a problem on another board
08:30 meeting
Wednesday, 15th June
  • 02:30-05:00 Replacement of relay for BIW in point5
  • 05:00 - 11:00: Problems at injection (Beam 1 particularly). RE-tuning of the injection for B1 and B2
  • 11:00 Again 400 V circuit breaker trip in RR13.
  • 11:00-19:00: Intervention by EL on the 400 V circuit breaker and verifications on the equipments connected to that.
    •  In the shadow access for:
      • cryo valve control connector in RE72
      • RF waveguides arc detectors
      • fire detection in UJ33
      • ATLAS
      • ALICE
      • 60 A power converters replacement
      • Enabled BLM in TD62
      • UPS control in US85
  • 19:00-21:00 Problem with the Beam imminent warning.
  • 21:00-23:00 Injection verification
08:30 meeting

Tuesday, 14th June

  • 07:30 Stable beams. Fill #1868. Initial luminosity 1.1x1033.
  • 22:37 Trip of Sector 81. Lost Cryo maintain due 400 V problem in RR13. End of physics #1868 ~47 pb-1 in 15 hours
  • 23:00 - 02:30 Access for: 400 V problem in UJ14, QPS card replacement in Sector 23 and 67.

08:30 meeting