LHC 2010 - latest news

Week 36: Machine coordinators: Ralph Assmann, Roger Bailey

Main aims of the week:

Statistics (from Mon 6/9/2010 07h to Monday 10/9/2010 07h)

  % Mon Tue Wed Thu Fri Sat Sun
Beam availability 66.7 22.5 15.5 9.5 12.0 15.0 20.5 17.0
Set-up without beam 12.8 1.5 4.0 4.5 2.5 4.0 1.0 4.0
Faults 20.5 0.0 4.5 10.0 9.5 5.0 2.5 3.0
  100.0 24.0 24.0 24.0 24.0 24.0 24.0 24.0

Bunch train commissioning plan (version 09/09/2010)

LHC coordination vistar

Day

Summary

Link to report from morning meeting

Monday 13th September   Slides from 08h30 meeting
Sunday 12th September
  • 07.00-10.00 Collimator problem
  • 10.00-15.00 Setting up new ramp
  • 15.00-24.00 Collimator set up 3.5 TeV with 170urad
  • 24.00-10.00 Ramp and squeeze set up
Slides from 08h30 meeting
Saturday 11th September

Decision based on Friday's results

Stick with 170urad Xing angle at injection. This will allow operation with any bunch spacing. Set up procedures to handle change of Xing angle through the operational cycle.

  • 07.00-15.00 RF setting up and energy matching
  • 15.00-23.00 Collimator set up 450GeV with wider TCTs
  • 23.00-07.00 Qualification of collimators (loss maps)
Slides from 08h30 meeting
Friday 10th September
  • 07.00-12.00 Hit a series of problems needing access
  • 12.00-13.00 Recover and cycle
  • 13.00-15.00 BPM interlock in point 6
  • 15.00-20.00 Injection of 3 trains of 8 for beam-beam
  • 20.00-02.00 Aperture studies
  • 02.00-06.00 Test ramp

Could reduce Xing angle to 80urad before affecting lifetime

Could reduce Xing angle to 20urad, 1h lifetime

Xing angle of 100urad OK for trains of 150ns

Predicted aperture measurements in squeeze do not exist

Measured n1=10-12 instead of predicted 7

Plenty of aperture in the triplets

Slides from 08h30 meeting
Thursday 9th September
  • 07.00-09.00 Recover from 3.5TeV and setting up
  • 09.00-14.00 Cryo problem
  • 14.00-22.00 Injection/Injection protection
  • 22.00-02.00 Access LHC then SPS problems
  • 02.00-04.00 Ramp and squeeze with Xing angles
  • 04.00-07.00 Beam lost PC trip. Access needed. Recover.
Slides from 08h30 meeting
Wednesday 8th September
  • 07.00-12.00 Scheduled access before long weekend
  • 12.00-14.00 Setting up
  • 14.00-19.00 Technical faults then setting up
  • 19.00-01.00 Injection/Injection protection
  • 01.00-07.00 Ramp and squeeze with Xing, beta-beating
Slides from 08h30 meeting
Tuesday 7th September
  • 07.00-13.00 Collimation at 450GeV
  • short access for RF
  • 15.00-20.00 Collimation at 450GeV
  • 20.00-01.00 Transverse damper
  • 01.00-07.00 Test ramp failed ..
Slides from 08h30 meeting

Monday 6th September

  • 02:00-04:00 Splash events for CMS: B1 - probe beam

  • 04:00-10.30 Ramp 10 A/s (chromaticity, crossing angle non-closure, beta-beating)

  • 12:00-19.00 Injection/Injection protection

  • 19.00-23.00 Transverse damper

  • 23.00-07.00 PLL commissioning / K modulation 450GeV

Slides from 08h30 meeting