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Beam Dynamics Newsletter No International Committee for Future Accelerators Sponsored by the Particles and Fields Commission of IUPAP Beam Dynamics Newsletter No. 64 Issue Editor: Y. Zhang Editor in Chief: W. Chou August 2014 3 Contents 1 FOREWORD .......................................................................................................... 9 1.1 FROM THE CHAIR ...................................................................................................... 9 1.2 FROM THE EDITOR .................................................................................................. 10 2 THEME: BEAM COOLING AND RELATED TOPICS (PART I) ............... 12 2.1 BRIEF HISTORY AND PRESENT STATUS OF COOLING METHODS IN EXPERIMENTAL PHYSICS .................................................................................................................. 12 2.1.1 Introduction .................................................................................................. 12 2.1.2 Past ........................................................................................................ 13 2.1.2.1 Introduction .................................................................................... 13 2.1.2.2 First Experiment ............................................................................. 13 2.1.2.3 Cooling Beam ................................................................................. 14 2.1.2.4 1990-2014: The Productive Years .................................................. 14 2.1.3 High Lights of Cooling Applications ........................................................... 15 2.1.3.1 Particle Physics .............................................................................. 15 2.1.3.2 Nuclear Physics .............................................................................. 16 2.1.3.3 Atomic Physics ............................................................................... 16 2.1.3.4 Particle Beam Physics .................................................................... 17 2.1.4 Present ........................................................................................................ 18 2.1.5 Conclusions .................................................................................................. 19 2.1.6 References .................................................................................................... 19 2.2 RECENT DEVELOPMENT IN STOCHASTIC COOLING APPLICATIONS .......................... 20 2.2.1 Introduction .................................................................................................. 21 2.2.2 FAIR Project ................................................................................................. 21 2.2.2.1 Pre-Cooling of Antiproton Beam in the Collector Ring ................. 22 2.2.2.2 Accumulation of Pre-Cooled Beam with Stochastic Stacking System22 2.2.2.3 Antiproton Accumulation in HESR ................................................. 23 2.2.2.3.1 Simulation Method ......................................................... 23 2.2.2.3.2 Moving Barrier Voltage Method .................................... 24 2.2.2.3.3 POP Experiment at the ESR ........................................... 26 2.2.2.4 Low Energy Antiproton Beam Production at FAIR ....................... 26 2.2.3 NICA Project ................................................................................................ 26 2.2.4 Stochastic Cooling at Electron Ion Collider Project ..................................... 28 2.2.5 References .................................................................................................... 29 2.3 OVERVIEW OF THE COOLING PROGRAM AT CERN ................................................. 29 2.3.1 Introduction to CERN ................................................................................... 29 2.3.2 Stochastic Cooling ........................................................................................ 30 2.3.2.1 First Ideas ....................................................................................... 30 2.3.2.2 The “ICE” Age ............................................................................... 31 2.3.2.3 The Antiproton Accumulator and the Antiproton Accumulator Complex .......................................................................................... 32 4 2.3.2.4 Antiprotons in the Intersecting Storage Ring (ISR) ........................33 2.3.2.5 The Low Energy Antiproton Ring (LEAR) ......................................33 2.3.2.6 The Antiproton Decelerator (AD) ...................................................34 2.3.3 Electron Cooling ...........................................................................................35 2.3.3.1 First Experiments on ICE ...............................................................35 2.3.3.2 Electron Cooling on LEAR .............................................................35 2.3.3.3 From LEAR to LEIR .......................................................................37 2.3.3.4 Electron Cooling on the AD ...........................................................38 2.3.3.5 ELENA, the Extra Low Energy Antiproton Ring ............................39 2.3.4 References .....................................................................................................40 2.4 DEVELOPMENT OF ELECTRON COOLERS IN NOVOSIBIRSK .......................................41 2.4.1 Introduction ...................................................................................................41 2.4.2 First Electron Cooler at NAP-M Storage Ring .............................................41 2.4.3 Test Bench for Magnetized Cooling (MOSOL) ...........................................42 2.4.4 SIS-18 Cooler ...............................................................................................42 2.4.5 CSRm and CSRe Coolers .............................................................................43 2.4.6 LEIR Cooler ..................................................................................................44 2.4.7 COSY Cooler ................................................................................................45 2.4.8 References .....................................................................................................47 2.5 FERMILAB’S 4.3-MEV ELECTRON COOLER .............................................................48 2.5.1 Introduction ...................................................................................................48 2.5.2 Recycler Electron Cooling (REC) System....................................................49 2.5.3 Electron Cooling Formulae ...........................................................................50 2.5.4 Cooling Measurements .................................................................................51 2.5.5 Conclusion ....................................................................................................54 2.5.6 Acknowledgement ........................................................................................54 2.5.7 References .....................................................................................................55 2.6 ELECTRON COOLING AT IMP ..................................................................................55 2.6.1 Introduction of CSR ......................................................................................55 2.6.2 Electron Cooling for CSR .............................................................................55 2.6.2.1 Functions of Electron Cooling .......................................................56 2.6.3 Main Physics Goals at CSR ..........................................................................56 2.6.4 Operation Modes of HIRFL-CSR .................................................................57 2.6.5 Electron Dynamics in the Cooling Devices ..................................................57 2.6.5.1 Adiabatic Expansion .......................................................................57 2.6.5.2 Toroids ............................................................................................57 2.6.5.3 Parallelism of Magnetic Field in the Cooling Section ...................58 2.6.5.4 Collector .........................................................................................59 2.6.6 Parameters Optimization of CSR ..................................................................59 2.6.7 Commissioning and Operation of Electron Cooling in CSR ........................63 2.6.8 Electron Cooling Experiments at CSR .........................................................63 2.6.9 Physics Experiments Related Electron Cooling at CSR ...............................63 2.6.10 Planned Experiments Related with Electron Cooling ....................63 2.6.10.1 Longitudinal Stacking .....................................................................63 2.6.10.2 Ion Beam Crystallization ................................................................64 2.6.10.3 High Energy Density Physics .........................................................64 5 2.6.10.4 Suppression of Instability of Ion Beam with Modulated Electron Beam ............................................................................................... 64 2.6.11 Status of HIRFL-CSR .................................................................... 65 2.6.12 Research Activities of HIRFL-CSR in Near Future ....................... 65 2.6.13 Summary .......................................................................................
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