Minutes of the 3rd CLIC-ILC BDS+MDI meeting, 19 July 2010.
*FACET Collimator wakefield experiment proposal
Deepa: missing RF simulations
Nigel: RF expert left. Good measurements might require good quality BPMs. Make sure measurement will be successful. Back of the envelope calculation might be enough.
Andre Seryi: SLAC probably have manpower.
Action: distribute beam-line parameters and default BPM resolution.
*CDR
Rogelio: The "Component specification" section does not exactly correspond to the "Accelerator Components" in the ILC RDR. Daniel replies that this was the aim so the title might be modified.
Daniel: we should check that CC is well covered. Solenoid goes into MDI. Vacuum and wakes should be covered superficially. Some feedbacks should be included but results go to emittance preservation. IP feedback mostly covered in MDI chapter.
Action: The experts of Crab Cavities, Collimation and Muon supressor should give talks with the status of the systems in the next meetings.
*CLIC MDI STATUS
Rogelio: Could the Muon Scrapers proposed by Lau be simulated by Lawrence. Grahame replies that yes once the field map is available.
Daniel: No cost in the CDR chapters.
MDI overlaps with some other chapters. Tolerances should go in the BDS chapter. Technical descriptions should go in the MDI chapter.
*Luminosity with Crab Cavities
Exact voltage from simulations 2.6 MV.
Increased tolerance on CC voltage. 22 mdeg tolerance on phase.
Roll tolerance ~ mdeg.
Vertical plane expanded by CC !! Consistent with beams going offcenter in FD quads.
5-10% luminosity loss due to this effect.
Andrea tested the CC for the ILC without surprises.
Compare beam distributions at sextupoles.
Andrei: Similar effects were evaluated in ILC. See:
http://www-project.slac.stanford.edu/lc/bdir/Meetings/beamdelivery/2005-01-25/index.htm (the document is attached to this minutes)
Daniel: Maybe a design issue, to be followed up.
* FFS tuning news
The IP angle did not do much. Further studies on-going.
*News on alternative tuning techniques
Andrea switched on synchrotron radiation for this tuning algorithm.
50 thin lenses are used for the dipoles (default is 5).
100000 particles are simulated.
Average sigmay after Andrea's tuning is 23.4nm.
Average sigmax after Andrea's tuning is 1250 nm.