LHC 2011 - latest news

Week 48: Machine coordinators: G. Arduini, M. Lamont

Goals of the week: Pb-Pb physics, ALICE polarity reversal, Van der Meer scans

 

Date

Summary

Link to report from morning meeting

Monday 5th Dec
  • 03:15 STABLE BEAMS #2343 Initial luminosity 5x1026 cm-2s-1

8:30 meeting

Sunday 4th Dec
  • 05:50 Beams dumped, end of physics #2340 ~6.2 ub-1 in 7:05 hours
  • 08:30 Access for RF PLC problem
  • 11:48 STABLE BEAMS #2341 Initial luminosity 4.6x1026 cm-2s-1
  • 14:55 Beam dump due to LBDS self trigger. End of physics  #2341 ~3.8 ub-1 in 3:07 hours
  • 18:26 STABLE BEAMS #2342 Initial luminosity 5x1026 cm-2s-1
  • 24:00 OP dump. End of physics #2342 ~5.6 ub-1 in 5:30 hours

9:00 meeting

Saturday 3rd Dec
  • 00:30 STABLE BEAMS #2338. Initial luminosity 3.7x1026 cm-2s-1 (still lower intensity from injectors).
  • 08:09 OP dump. End of physics #2338. 5.6 ub-1 in 7:40 hours.
  • 14:05 STABLE BEAMS #2339 Initial luminosity 4.9x1026 cm-2s-1
  • 20:00 OP dump. End of physics #2339. 5.1 ub-1 in 5:55 hours.
  • 22:45 STABLE BEAMS #2340 Initial luminosity 5.1x1026 cm-2s-1

9:00 meeting

Friday 2nd Dec
  • Some delay re-filling - SPS/LINAC3
  • Back in stable beams 04:15
  • 13:18 Stable beams #2337 - Van der Meer scan in ATLAS and CMS
  • 17:29 Trip of Sector 12 (QPS B10.L2- communication lost – SEU?). End of STABLE BEAMS #2337 – 3.2 ub-1 in 4:15 hours. access required for QPS (card replacement).

8:30 meeting

Thursday 1st Dec
  • 00:30 access for beam dump fault
  • 03:00 beam in
  • 05:00 stable beams
  • 10:45 beams dumped
  • Refilled for physics & Van der Meer scans (Alice)
  • Scans good - fill dumped 21:15

8:30 meeting

Wednesday 30th Nov
  • Preparation of ELQA. Recovery of the cryo-conditions at the DSLC ongoing.
  • Crygenics OK by 16:30, ELQA and EPC finished by 17:00
  • Powering tests during the evening
  • 23:00 start pre-cycle

8:30 meeting

Tuesday 29th Nov
  • Cryo recovery + access
  • Temperature on DSLC increased to 240 K during the morning afternoon due to the degraded insulation vacuum ==> ELQA+powering tests required for the circuits powered via the DSLC

8:30 meeting

Monday 28th Nov
  • 05:00 Dump fill 2340, integrated L ~6.5 ub-1.
  • 07:00 Flipping ALICE polarity to POSITIVE.
  • Preparing test ramp, squeeze, collisions.
  • 12:00 TCT setting-up after crossing angle swap during adjust
  • 13:30-14:30: loss maps and asynch dump test
  • 17:15 fill for physics
  • 19:11 Stable Beams #2332. Initial luminosity 5.1x1026 cm-2s-1
  • 20:23 Beam dump due too RF trip. End of fill #2332. 1.9 ub-1 after 1.2 h
  • 20:26 Cooling tower stop in point 4. Lost cryogenics.

8:30 meeting