Beam Physics for FAIR workshop July 6-7, Darmstadt https://indico.gsi.de/conferenceDisplay.py?confId=1031

FAIR (facility for Antiproton and Ion Research) Founding of FAIR GmbH expected end of August  company that should manage the FAIR project Modularized start version of FAIR, first modules include SIS100, but not SIS300. Current planning for end of construction: end 2015. Talks Design study for the HESR ring done by Julich (Bonn)  impedance calculated with SIMBAD based on ORBIT. Pavel Zenkevich for ITEP (Moscow)  IBS and space charge for FAIR and ITEP Valery Kapin  MADX modeling of SIS 100 and benchmark with MICROMAP Also work on: slow extraction from SIS100 proton and heavy ion halo collimation (FLUKA, SRIM) and beam induced activation linear coupling with space charge Laser acceleration RF manipulations electron cloud effects with coasting beam in SIS18 (HEADTAIL simulations from F. Petrov). Impedances U. Niedermayer  theory (Al Khateeb and Vos) and simulations for a very thin beam pipe at low frequencies (wakefield method and loss method from Tom Kroyer) L. Haenichen  SIS100 kicker simulations (Specialized frequency domain solver for beam excitation introduced by B. Doliwa et al) and studied the issues with the ferrite model used in time domain Signals from embedded BPMs in collimators (U. Niedermayer) SIS18 Multi turn injection and micro bunch evolution simulations

My remarks Possibility to invite Lukas, Uwe, Oliver… to our impedance meetings via webcast Al Khateeb formula works at low frequency only with a non trivial Fortran code from Reiner Hasse or Tom? We provided our Rewall code to them. 1st task for them is to check with Al Khateeb’s formula. Oliver mentioned that it was great that CERN had so many people involved in « impedance team » Oliver said it was a good idea to have the RF people strongly involved in longitudinal instabilities as the harware (phase loop, imperfections) is so important. In this frame, having the longitudinal collective effects within the RF group is an asset. Oliver would like that Vladimir shares his results with us before HB. Oliver mentioned that he would not use HEADTAIL for longitudinal simulations. He uses his own code LOBO. He says the matching of the bunch to the bucket is critical and this seems to be true. Opportunity to work towards a new code? They are debating the need for collimation in SIS100. Effect of ions? Oliver proposed to Ralph that some tests can be performed at GSI for ion collimation, but no answer. New diagnostics at SIS18 for longitudinal dynamics (Olexander Charnyi) Advice from Wolfgang Muller (TU)  there should be no tetrahedral mesh for wakefield solver  Japanese PhD student tries to make I-solver work with wakefield solver and it seems there is not much gain yet compared to the classical TD solver  very large and easy improvement when using this GPU acceleration method (more than with a cluster!!!!). Maybe useful for Carlo and Hugo? We should ask for a cost estimate and do a test with one input file.  64 bits OS!!!!!!

Main directions of theoretical studies at ITEP. P. Zenkevitch Main directions of theoretical studies at ITEP. Main directions of theoretical studies are connected mostly with our accelerator complex and FAIR design. The significant part of them are made with close collaboration with GSI beam physics group, especially with Prof. I. Hoffmann, Prof. O. Boine-Frenkenheim and D-r G.Franchetti, and Juelich accelerator physicists: D-r A. Lerach and D-r Yu. Senichev. Our studies are devoted the following topics: Development of numerical methods for slow IBS analysis. Numerical modeling of space charge effects. Nechoroshev’s theorem and its application to octupole families.of SIS100 Correction of perturbations due to errors of magnetic field (closed orbit distortions , beta-function distortions and so on). One-beam coherent instabilities/ Multi-species studies (beam neutralization, collective instabilities in presence of electron cooling systems). Slow ejection schemes and its optimization. Final beam compression by voltage jump. I will consider mostly the first four points which seems to me the most interesting ones for present meeting..

U. Niedermayer Power Loss Method (4)

Power Loss Method (4): Mesh U. Niedermayer Power Loss Method (4): Mesh

SIS100 Beampipe U. Niedermayer Source: Detailed Specifications for SIS 100 dipole chamber with supplementary cooling tubescontact cooling

Ferrite Material Modeling (3) : Dispersion Model for Time Domain L. Haenichen Ferrite Material Modeling (3) : Dispersion Model for Time Domain Typically we have different for every frequency How about time domain ? Dispersion model fitted to frequency domain data [Gutschling 1998] … How does it compare ? Time domain dispersion model does not entirely capture the characteristics…

Ferrite Material Modeling (4) : Dispersion Model for Time Domain L. Haenichen Ferrite Material Modeling (4) : Dispersion Model for Time Domain Idea: Split frequency range in multiple decades Matches the characteristics better but causes discontinuity of permeability Multiplies calculation time Effect on results ? To be tested …

SIS 100 Kicker simulation status (2) : yoke only L. Haenichen Longitudinal Z Good agreement found between both methods Deviation is probably a result of different ferrite modeling in time and frequency domain