HiLumi Beam-Beam Task 2.5 Meeting Minutes
October 4, 2012
recorded by A.Valishev

Attendance: S. Paret, T. Pieloni, J. Qiang, D. Shatilov, S. White, A. Valishev

- Sasha gave a refresher on the task goals and near-term plan. The two main
directions are weak-strong (a. DA, life-time for HL-LHC; b. simulation of the
present machine performance & MDs) and strong-strong (a. single-bunch effect
with b-b and impedance; b. single-bunch effect with crab cavity).
- Tatiana announced that a new EPFL fellow (Name?) will start on November 1.
His assignment will be the weak-strong simulations with SixTrack.
G. Demolaize (BNL) may be interested in taking part in SixTrack 6D beam-beam
investigation (Sasha will check how this can be arranged administratively).
- Sasha will create an email distribution list.
- Tatiana is working on the task web page.
- Stefan finished simulations of last year's MD (leveling with transverse
separation). His results are in agreement with the experiment. Summary
was presented at the High Brightness workshop.
- Simon implemented impedance model in stron-strong simulation and has
some important results. His recent talk can be found here:
http://emetral.web.cern.ch/emetral/ICEsection/2012/2012-10-03/SB_Coherent.pdf
A proposal is being developed for the next MD block.
- Tatiana works on modeling the bunch-by-bunch orbit from beam-beam. There
is also a plan to include impedance into COMBI.
- Ji and Stefan switched to the studies of effect of crab cavity noise on
emittance growth.
- Werner and Tatiana work on the MD proposal. So far we do not see and HiLumi-
specific experiments we can suggest. The link to past MD notes:
http://lhc-beam-beam.web.cern.ch/lhc-beam-beam/notes/
- Sasha gave a brief introduction to the flat beams option, that was recently
brought up by A. Burov. Sasha looked at the luminosity leveling scenario
that does not involve the use of crab cavity, and so far the results look
promising. More analysis is needed.
- At the coming HiLumi/LARP meeting in Frascati we will have to talks:
a summary talk by Sasha (Beam-beam effects: status and plan) and Simon
with his strong-strong+impedance results. Tatiana, Simon, Dmitry and Sasha will
attend (+Mikhail, of course).