LHC 2011 - latest news

Week 28: Machine coordinators: Mike Lamont, Jan Uythoven

Planning - after recovery - outstanding items:

  1. Default is to continue with the satellite collision scheme (unless requested otherwise by ALICE):
    1. 50ns_264b_249_0_240_36bpi8inj (1 fill): Done
    2. 50ns_840b_807_0_816_108bpi12inj (1 fill): Done 2 x
    3. 50ns_1092b+1small_1042_35_1008_108bpi 
      1. Alice back to bunch collisions!
    4. 50ns_1380b_1331_0_1320_144bpi12inj.txt (luminosity production)
      1. MKI pulse length might need increasing

LHC coordination vistar

Day

Summary

Link to report from morning meeting

Monday, 18th July
  • 03:42 Fill #1955, 1092b, stable beams
  • 09:50 Beams dumped, trip of RQTL7.L7B1
Sunday, 17th July
  • 01:05 Dump fill #1952 by operator - 820b
  • 04:36 Stable beams fill #1953 - 820b
  • 10:15 Dump fill #1953 - access system fault
  • 14:30 Injecting probe beams
  • 16:00 Dumped beam at inj., RQTL9.L3B2 QPS trip - OK to continue
  • 17:41 Finished injecting and wait one hour before ramping
  • 19:34 Stable beams fill #1954 - 1092 bunches -lumi's 1160e30: back in production!
  • 22:58 Beam dumped due to RF HOM power interlock
Saturday, 16th July
  • Three fills lost overnight Friday to Saturday (840 bunch attempts): first, QTF trip QP/tune feedback during squeeze; next two to MKI UFOs while optimizing collisions.
  • 08:45 trip of sector 81 - QPS glitch
  • 11:00 Injecting probes – problems in injector chain
  • 13:00 Filled – wait 30 minutes before ramp
  • 14:09 At flat top: dumped  - UFO IP2 (assigned to MKI-D)
  • 16:15 Injecting for physics – SPS some problems setting up; some injection losses in the LHC Injecting 840b,  but lower intensity and emittances up to 3.0 um @ inj.
  • 19:15 Stable beam fill #1952
Friday, 15th July
  • 00:30 Stable beams,  fill #1945, 264 bunches 
  • 03:30 Dumped, fill #1945, 264 bunches
  • 04:30 Injecting probes, filling for fill with 840 bunches
  • 06:34 Lost beam during adjust, Software interlock triggered on Voltage interlock of point 7 BLMs.
  • 09:00 Access for Atlas and RF
  • 14:00 Lost cryo maintain in MSR7 during precycle due to a faulty temperature sensor on RQTL9.R7B2
  • 18:00 Closing machine and pre-cycle
Thursday, 14th July
  • 04:00 Loss maps at injection
  • 07:00 Check injection of trains, 12 & 36 bunches
  • 09:00 Access – 2 hours
  • 11:45 Start pre-cycle
  • 12:50 Injecting
  • 13:20 ADT check
  • 14:50 Injecting for physics
  • 16:45 Stable beams fill #1944, 48 bunchesn1
  • 9:20 Dumped, RF Power interlock
  • 22:15 Injecting again
Wednesday, 13th July
  • 9:30 Stable Beams… with 1 pilot and 2 nominals
  • 11:10 Loss maps at 3.5 TeV: Ralph says OK
  • 12:45 Check relative position TCDQ – TCSG B2
  • 14:45 Collimator position checks at injection
  • 18:15 In parallel scraping of full beam TCDQ – TCSG
  • 21:00 RF phasing n22:00 BLM 2.5 V problem -> replace this morning
  • 23:00 Asynch dump injection n24:00 Asynch dump at 3.5 TeV
Tuesday, 12th July
  • Finishing recovery from power cut
  • 13:45 Ramp complete machine without beam
  • 15:15 Probe beams injected, preparing for TCDQ - TCSG relative position measurement
Monday, 11th July
  • Recovery from power cut on-going