R&D GOALS AND MILESTONES TOWARDS A TECHNICAL DESIGN REPORT TDR (2008) First Intnl. Teleconference Ecloud, Impedance/Instabilities - M. Pivi, SLAC 31 October 2006

2.2.3 Electron Cloud Characterize electron-cloud build-up Required for Baseline Priority: Very High Develop electron-cloud suppression techniques Required for Baseline Priority: Very High Develop modeling tools for e-cloud instabilities Required for Baseline Priority: Very High Determine electron-cloud instability thresholds Required for Baseline Priority: Very High Electron Cloud: Objectives

Characterize electron-cloud build-up A Model electron cloud instability, Christine Celata, LBNL C Model electron-cloud build-up and instabilities, Rainer Wanzenberg, DESY D Model electron-cloud build-up and instabilities, Jim A. Crittenden, Cornell H Electron cloud studies in DAFNE, Roberto Cimino, INFN-LNF I CESR-TF wiggler and electron cloud studies, John Byrd, LBNL M Measurement of electron cloud instabilities, John Flanagan, KEK N Benchmarking of electron-cloud build-up simulations, Frank Zimmermann, CERN O Improvement of electron-cloud simulation codes, Frank Zimmermann, CERN Q Experimental determination of surface parameters for electron-cloud build-up, Frank Zimmermann, CERN Develop electron-cloud suppression techniques F Electron cloud lab measurements and PEP-II studies, Mauro T.F. Pivi, SLAC G Studies of clearing electrodes for suppressing electron cloud build-up, Mauro T.F. Pivi, SLAC K Studies of grooved vacuum chamber surfaces for electron cloud suppression, Mauro T.F. Pivi, SLAC L Experiments on suppression of electron cloud effect, Yusuke Suetsugu, KEK N Benchmarking of electron-cloud build-up simulations, Frank Zimmermann, CERN Develop modeling tools for electron-cloud instabilities A Model electron cloud instability, Christine Celata, LBNL B Model electron-cloud build-up and instabilities, Mauro T.F. Pivi, SLAC C Model electron-cloud build-up and instabilities, Rainer Wanzenberg, DESY D Model electron-cloud build-up and instabilities, Jim A. Crittenden, Cornell E Model electron cloud build-up and instabilities, Kazuhito Ohmi, KEK M Measurement of electron cloud instabilities, John Flanagan, KEK R Develop a PIC code for computing electron cloud and ion effects, Warner Bruns, CERN Determine electron-cloud instability thresholds B Model electron-cloud build-up and instabilities, Mauro T.F. Pivi, SLAC C Model electron-cloud build-up and instabilities, Rainer Wanzenberg, DESY D Model electron-cloud build-up and instabilities, Jim A. Crittenden, Cornell M Measurement of electron cloud instabilities, John Flanagan, KEK P Predict electron-cloud effect in the damping rings, Frank Zimmermann, CERN Electron Cloud: List of Activities

4 Electron cloud issues: Milestones 1.Characterize the electron cloud build-up 2.Test clearing electrodes a)characterize impedance, HOM, power load b)Installation of chambers with clearing electrodes in existing machines including dipole and wiggler sections c)develop diagnostic 3.Test groove concepts a)characterize impedance, HOM b)Installation of fin chambers in existing machines including bend and wiggler sections c)develop diagnostic 4.Test coating techniques a)characterize and test the conditioning in situ in existing machines 5.Characterize the electron cloud instability threshold 6.Integrated modeling: cloud, impedance, space charge 7.Specify techniques for suppressing electron cloud in the ILC DR Investigate alternative solutions

5 Electron cloud Milestones: Investigators 1.Characterize the electron cloud build up There have been significant progress in characterizing the build-up in most areas of the damping rings, and the simulations have been benchmarked and are believed to be reliable. However, there are still uncertainties in the wiggler sections where the electron cloud have a significant impact. Further studies are needed. wiggler 3D simulations CLOUDLAND, L. Wang wiggler 3D simulations WARP/POSINST, C. Celata wiggler experimental studies in CESR, M. Palmer cloud density measurements by RF transmission in PEP-II, J. Byrd characterize ecloud in quadrupole by simulation, M. Pivi characterize ecloud in quadrupole by simulation, C. Celata fill pattern as possible mitigation by simulation, M. Venturini compile e-cloud density over the machine by simulation, M. Pivi

6 Electron cloud Milestones: Investigators 2. Test clearing electrodes (a) characterize impedance, HOM, power load analytical estimates simulate MAFIA, A. Krasnyhk, Cho Ng simulate with VORPAL, V. Ivanov (?) simulate, F. Caspers simulate, D. Alesini (b) Installation of chambers with clearing electrodes in existing machines, bend and wigglers test in HCX in a quadrupole or drift region, A. Molvik optimize clearing electrode design for bend, L. Wang test in ESA preliminary to PEPII installation, M. Pivi, test in PEPII in bend chicane, M. Pivi optimize clearing electrode design for wiggler, M. Palmer test in CESR in wiggler section, M. Palmer test in KEKB arc section bend or wiggler section, Y. Suetsugu test in LHC arc section bend section, F. Caspers (c)develop diagnostic electron cloud diagnostic for test chambers, A. Molvik electron cloud diagnostic for test chambers, R. Macek

7 Electron cloud Milestones: Investigators 3. Test groove concepts (a) characterize impedance, HOM K. Bane numerical estimation, G. Stupakov analytical (b) Installation of fin chambers in existing machines including bend and wigglers optimize clearing grooves design, W. Bruns optimize clearing grooves design, L. Wang optimize clearing grooves design, M. Venturini rectangular grooves in drift sections SLAC, M. Pivi triangular grooves in bend sections SLAC, M.Pivi triangular grooves in wiggler section CESR, M. Palmer (c)develop diagnostic electron cloud diagnostic for test chambers, A. Molvik electron cloud diagnostic for test chambers, R. Macek

8 Electron cloud Milestones: Investigators 4. Test coating techniques and determine conditioning effectiveness (a) Secondary electron yield measurements measuring SEY, Y. Suetsugu measuring SEY, R. Kirby measuring SEY, (N. Hilleret) (b) machine studies installation of test chambers in KEKB Cu, TiN, NEG, Y. Suetsugu SEY conditioning test in PEP-II, M. Pivi Installation of chambers in CESR, M. Palmer (c) manufacturing and diagnostics building chambers for installations, S. Marks

9 Electron cloud Milestones: Investigators 5. Characterize the electron cloud instability Characterize single-bunch instability PEHTS, K. Ohmi Characterize single-bunch instability HEAD-TAIL, F. Zimmermann Characterize single-bunch instability quasi-static QUICKPIC, P. Spentzouris Characterize single-bunch instability in wiggler 3D WARP, C. Celata Characterize single-bunch instability in lattice CMAD, M. Pivi

10 Electron cloud Milestones: Investigators 6. Integrated modeling Characterize instability FRAMEWORK, P. Spentzouris

11 Electron cloud Milestones: Timescale 1. Characterize the electron cloud build up Compile list of electron cloud density in ring by Test clearing electrodes In PEP-II by 2007 In CESR by Test groove concepts In PEP-II by 2007 In CESR by Test coating techniques In KEKB, by 2007 In PEPII, by 2007 In CESR, by Characterize the electron cloud instability by TDR 6. Integrated modeling by TDR 7. Specify techniques for suppressing electron cloud in the ILC DR by TDR

2.2.4 Ion Effects Characterize ion effects Required for Baseline Priority: Very High Specify techniques for suppressing ion effects Required for Baseline Priority: Very High Ion Effects: Objectives

Characterize ion effects R Develop a PIC code for computing electron cloud and ion effects, Warner Bruns, CERN A Experimental studies of fast ion instability at the LBNL-ALS, John Byrd, LBNL B Numerical and analytical studies of two-stream (beam-ion) instabilities, Lanfa Wang, SLAC C Studies of fast ion instability, Kazuhito Ohmi, KEK D Studies of fast ion instability, Guoxing Xia, DESY E Studies of fast ion instability, Jim A. Crittenden, Cornell G Experimental studies of fast ion instability, Lanfa Wang, SLAC H Measure fast ion instability in KEK-ATF, Junji Urakawa, KEK I Characterize ion effects in the damping rings, Frank Zimmermann, CERN Specify techniques for suppressing ion effects B Numerical and analytical studies of two-stream (beam-ion) instabilities, Lanfa Wang, SLAC E Studies of fast ion instability, Jim A. Crittenden, Cornell F Studies of suppression techniques for fast ion instability, Lanfa Wang, SLAC Ion issues: List of Activities

14 Ion effects issues: Milestones and Investigators 1. Characterize ion effects for the ILC DR R Develop a PIC code for computing electron cloud and ion effects, Warner Bruns A Experimental studies of fast ion instability at the LBNL-ALS, John Byrd B Numerical and analytical studies of two-stream (beam-ion) instabilities, Lanfa Wang C Studies of fast ion instability, Kazuhito Ohmi D Studies of fast ion instability, Guoxing Xia E Studies of fast ion instability, Jim A. Crittenden G Experimental studies of fast ion instability, Lanfa Wang H Measure fast ion instability in KEK-ATF, Junji Urakawa I Characterize ion effects in the damping rings, Frank Zimmermann 2. Test suppression techniques for ion effects F Studies of suppression techniques for fast ion instability, Lanfa Wang 3. Specify techniques for suppressing ion effects in the ILC DR … To be discussed: set milestones and investigators, examples:

15 Ion effect issues: Timescale To be discussed: set milestones timescale: 1. Characterize ion effects for the ILC DR by date … 2. Test suppression techniques for ion effects by date … 3. Specify techniques for suppressing ion effects for the ILC DR by date …