----------------------------------------------------------------------- Minutes of the ABP-LCE team meeting of 03.12.04 present: WH, EM, TP, DS, EV, FZ excused: EB, JR, FR ----------------------------------------------------------------------- (1) Pending Actions & News ---------------------------- ACTION -> EM and/or FZ will review Landau-damping mechanisms. STATUS: pending. Very low priority. ACTION => EM will contact B. Zotter to investigate the possibility of a presentation in the near future. STATUS: pending. (2) Meetings ------------ EV presented results to the CNGS Project Technical Working Group. The predicted beam losses for the CNGS beam at the extraction from the SPS are within specifications. The only open question is the situation at the start and end of a batch. WH informed the team that next week there will be 3 relevant meetings: (1) group reorganization (2) LHC MAC (9.12. open, 10.12. closed session) (3) LTC (impedance presentation) (3) Ongoing Activities ---------------------- EV is also working on the resistive-wall instability. He treats the problem from an analytical side, using group theory and symmetry arguments, and in simulations. He attempts to convert Kohaupt's paper for fillings with gaps into his formalism, and has been searching related literature in DESY, ESRF and Berlin. WH is working 100% on MADX. He will give a presentation in the next optics meeting. There is an initiative to apply the MADX orbit correction to the PS. TP reported on a simulation effort of different excitation mechanisms in the presence of long-range beam-beam interaction. In the program Coherent Multi Bunch Interaction (COMBI) she can excite 1 or several bunches (in various ways, e.g. uniform kick or random) and observe the resulting tune spectrum from a variable number of bunches. This study will allow a firmer specification of the LHC beam instrumentation needs. FZ is preparing papers for HHH-2004 proceedings. Among other aspects he is repeating simulations of electron-cloud heat loads and densities for the nominal and ultimate LHC using the newest version of the ECLOUD code. He is also looking at some of the proposed upgrade scenarios. The lifetime reduction along two batches seen in the SPS resembles the electron-cloud build up. Some SPS simulations are being performed to explore this correspondence. FZ is also working on MADX Touschek module. He hopes to finish this module before Christmas, with the help of Frank Schmidt. (4) Impedance Presentation to LTC --------------------------------- EM was not too sure which topics to present to the LTC. He would have preferred FR gave this talk. It was suggested that he emphasizes the difficulties encountered (e.g., collimator trapped modes depend on the gap settings, kicker ferrite properties not known at high frequencies) and to spend time on the main impedance items (collimators, kickers, resistive wall, exotic contributions like electron-cloud). DS and FZ will send some more suggestions or slides to EM for preparing this talk. Attached: Slide by TP