LHC 2011 - latest news

Week 26: Machine coordinators: Gianluigi Arduini, Mike Lamont, Bernhard Holzer (Thursday and Friday)

MD Coordinators: Ralph Assmann, Frank Zimmermann

Goals of the week: Luminosity production - 1380 bunches - Machine Development

LHC coordination vistar

Day

Summary

Link to report from morning meeting

Monday, 4th July
  • 06:00 Start of Technical Stop

08:30 meeting

MD report

Sunday, 3rd July
  • 23:00 - 09:00 ATS MD: squeezed to 0.3 m in IR1
  • 10:00 Injection for MD on beam distribution
  • 11:00-14:00 MD on beam distribution: problems in measuring tune and chromaticity. Fixed at the end of the MD
  • 14:20 Start of Quench at injection MD (B1) and TCLIB MD on beam 2
  • 15:30-17:30: SPS extraction interlock problem
  • 23:00 Start MD on R2E

09:00 meeting – MD report

Saturday, 2nd July
  • 04:00 MD on non-linear dynamics: dynamic aperture on B1 and non-linear chromaticity measurement and correction on beam 2
  • 10:00 No beam 1 from SPS (BETS card failure). End of MD on dynamic aperture on B1. Non-linear chromaticity measurement continues.
  • 13:00 B1 available from SPS. End of non-linear dynamics MD
  • 13:00 Issue pre-cycling RCO circuits
  • 15:00 End of pre-cycle for spool pieces. Start injection for collimation MD
  • 17:00 Start collimator MD
  • 21:30 End of Collimation MD. Start preparation for ATS MD.
  • 23:00 - Start injection in ATS optics

09:00 meeting – MD report

Friday, 1st July

  • 01:40 Recovery from injection MD.
  • 03:18 Start RF MD. Ongoing… Decided to delay intervention on ADT damper to Friday afternoon. RF MD will be ended 2h early: 14:00 Then access…
  • 18:00 Long-range beam-beam MD.

08:30 meeting – MD report

Thursday, 30th June

  • 07:02 Beam dump. End BI MD. Ramp down and cycle.
  • 07:45 Access for repair of wire scanner power supply and circuit breaker of AC dipole.
  • 08:21 Access finished. Prepare for head-on beam-beam MD.
  • 08:51 Wrong sequence manipulation (“LOAD-DRIVE INJECTION SETTINGS IN PC” while converters playing functions) à trip of RB’s in all sectors. H. Thiesen managed to switch back ON the PCs. Then drive them at injection. Injected without precycle of the mains. OK for beams.
  • 08:51 Problem to open TED downstream of TI8. No beam 2! Traced back to an issue with the LHC access system
  • 12:53 Both beams available for beam-beam MD. Beam-beam MD can start. Collided successfully beams with twice nominal bunch intensity and half nominal emittance! No beam-beam limit encountered.
  • 14:45 No beam from SPS (18 kV intervention)
  • 16:48 Start injection MD (nominal emittances, MKI’s, UFO’s)

08:30 meeting – MD report

Wednesday, 29th June

  • 04:30 End of setting-up of 90 m optics
  • 04:30 Ramp down and preparation for ATS dry run
  • 09:00 End of ATS dry run and preparation for 25 ns injection
  • 10:00-16:00: injected trains of 25 ns beams (24 bunches) up to 196 bunches spaced by 25 ns on both beams
  • 16:00-22:00 injected and stored single bunches of more than 2.5x1011 p/bunch
  • 22:00-06:00 MD on beam instrumentation.

08:30 meeting

Tuesday, 28th June

  • 02:17: 1901 - first fill with 1380 bunches into stable beams at around 02:15 without too many problems
  • 16:00 Beam dumped by OP. End of fill #1901. Integrated luminosity ~46 pb-1 after 13.7 hours
  • 16:00-19:20 Ramp down - Access for BI. Loading of 90 m optics hypercycle. Cleaning of the water cooling filters for cryo in point 2.
  • 19:20 start injection for 90 m optics

08:30 meeting

Monday, 27th June
  • 02:20 Stable beams #1900 1236b initial luminosity 1.25x1033 cm-2s-1.
  • 22:25 Beam dumped by OP. End of stable beams #1890. Integrated luminosity > 60 pb-1 in ~20 hours

08:30 meeting