• Follow up of actions
  • VELO detector and spectrometer strength for LHCb -> YP
  • The results including the effect of compensator failure will be presented in the following meeting.
• Report from meetings
  • MEB -> SF
  • The allocation in the last sector 1-2 of dipoles will start at the end of the month.
  • 1050 dipoles approved up to now.
  • Less than 15% of the SSS missing (around 50).
  • 2 warm magnets and the septa are missing.
  • 60% of the SpSSS are approved.
  • TCC -> BJ
    • There was a discussion about access cards. If the card is ok for entering the CCC, it will be ok for everything.
    • The QRL of the last arc will be finished by the end of this month.
    • SSS184 will be brought back to the surface as it features a leak in one of the V-lines.
    • The interconnection works takes place from Monday to Thursday and continues during the week-end for sector 2-3 but only for dipoles.
    • Everything will be delayed by the installation of the last dispersion suppressor quadrupoles.
    • A draft installation plan was presented by Sylvain Weiss.
      
• Recent results on beta-beating correction -> Rama Calaga (pdf file)
• A Recapitulation of the study was first presented, showing the observables, the method and ingredients of the simulation.
• Dispersion matching is spoilt when not included in the SVD correction algorithm. However, it does not improve significantly when included in the global algorithm.
• A first attempt of introducing weights for β-beat and dispersion correction was tried in a random error scenario in order to speed up the simulations:
• β-beat correction is sensitive to weights but this is not the case for the dispersion.
• If one excludes the IR quads the correction of dispersion is better. SF comments that not all the IR quads should be switched off for correcting dispersion  (only from Q1 to Q7).
• Using multiple iterations the correction becomes efficient for dispersion using as observable the ratio between dispersion and β^½  (shown also for the realistic errors scenario).
• Ideas for applying the algorithm to a real machine are outlined.
• Some results on coupling correction from RHIC are also shown.
• SF comments that 210 knobs seem a big number. It may be that some knobs are indeed either not independent or not usable as correctors. RC replies that he will check on that.
• SF adds that one may soft-wire magnets that only affect dispersion or β-beat for a more efficient correction.
• HB reminds that some locations need hard constraints (for injection, IP, etc), and need infinite weight. One should be concentrated also to a measure of the emittance blow-up.
• MG points out that the study has to be done for both beams and some knobs may be common (e.g. IR quads). RC replies that all the above requests will be taken into account.
• MG comments that the final version of the algorithm should be considered as part of the MAD-X on-line model.
  
• Highlights of ICAP06 Conference -> FS (pdf file)
  • It was a small conference of 90 participants of mostly European and Americans (no Asians, hardly any Russians).
  • MAD-X seems to have gained the status of a “gold standard” in the community.
  • The CHEF code at Fermilab seems to have overcome some serious limitation and is ready for ILC use by now.
  • MAD-X parser raised a lot of interest.
  • The “universal” parser between codes AML (Accelerator Markup Language) by D. Sagan (Cornell) is making progress and within the next 6 months MAD-X should become a central part in it.
  • An agreement with M. Berz about the use of the DA package in PTC was found.
• AOB
  • New error tables in optics database -> TR
• New versions of the error tables including the latest measurement results for correctors, such as MQS, MQT, as well as MQM, MQY and MQTL were generated.
• For MQM and MQY: magnetic errors are based on the latest results from cold magnetic measurements.
• For MQTL: magnetic errors are based on the latest results from the warm magnetic measurements including the correction for the effect of the too short measurement mole.
• Two version of the error table were produced (depending on the version of the error routines). All the error tables were moved to a new sub-directory in the official repository, namely /afs/cern.ch/eng/lhc/optics/errors.

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