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Laboratori Nazionali Di Frascati International Committee for Future Accelerators Sponsored by the Particles and Fields Commission of IUPAP Beam Dynamics Newsletter No. 51 Issue Editor: S. Chattopadhyay Editor in Chief: W. Chou April 2010 3 Contents 1 FOREWORD ........................................................................................................ 11 1.1 FROM THE CHAIRMAN ............................................................................................. 11 1.2 FROM THE EDITOR .................................................................................................. 12 2 INTERNATIONAL LINEAR COLLIDER (ILC) ............................................ 14 2.1 FIFTH INTERNATIONAL ACCELERATOR SCHOOL FOR LINEAR COLLIDERS ............... 14 3 THEME SECTION: ACCELERATOR SCIENCE AND TECHNOLOGY IN THE UK ................................................................................................................ 20 3.1 OVERVIEW – AN EMERGING PARADIGM OF COLLABORATION BETWEEN UNIVERSITIES, NATIONAL FACILITIES AND INDUSTRY ............................................ 20 3.1.1 Introduction .................................................................................................. 20 3.1.2 Mission of UK Accelerator Science and Technology .................................. 20 3.1.3 The Model: Integrated Accelerator Community and Stakeholders .............. 21 3.1.4 The Research Program Driven by Science ................................................... 21 3.1.4.1 Research Focus: Current ............................................................... 22 3.1.4.2 Reasearch Focus: Future ............................................................... 22 3.1.4.3 Special Comment on the Role of Test Facilities ............................. 22 3.1.5 The Research Program Driven by Applications ........................................... 22 3.1.5.1 Energy and Environment ................................................................ 22 3.1.5.2 Health and Medicine ...................................................................... 23 3.1.5.3 Security ........................................................................................... 24 3.1.6 Summary and Conclusion ............................................................................. 24 3.1.7 Reference ...................................................................................................... 24 PARTICLE AND NUCLEAR PHYSICS .................................................................... 25 3.2 THE UK LHC, LHEC AND ATLAS FORWARD PHYSICS PROGRAMME ................... 25 3.2.1 The LHC, LHeC and ATLAS Forward Physics ........................................... 25 3.2.2 The LHC ....................................................................................................... 25 3.2.2.1 Background Conditions in the LHC ............................................... 25 3.2.2.2 Machine Protection ........................................................................ 26 3.2.3 The LHeC ..................................................................................................... 27 3.2.3.1 Interaction Region Design.............................................................. 27 3.2.4 ATLAS Forward Physics ............................................................................. 29 3.2.4.1 The Integration with the LHC Machine ......................................... 29 3.2.5 References .................................................................................................... 29 3.3 LHC, FP420 AND SPS BEAM COUPLING IMPEDANCE STUDIES AND MITIGATION METHODS ................................................................................................................ 30 3.3.1 Introduction .................................................................................................. 30 3.3.2 Analysis of Beam Impedance for LHC and FP420 ...................................... 30 3.3.3 Current Research: Collimator and Kicker Beam Reduction Research ......... 31 4 3.3.4 Summary .......................................................................................................31 3.3.5 References .....................................................................................................31 3.4 THE INTERNATIONAL LINEAR COLLIDER.................................................................32 3.4.1 The Positron Source ......................................................................................32 3.4.1.1 Description of the Source ...............................................................32 3.4.1.2 The Undulator.................................................................................32 3.4.1.3 The Target.......................................................................................33 3.4.1.4 Summary .........................................................................................34 3.4.1.5 References .......................................................................................34 3.4.2 The Beam Delivery System ..........................................................................35 3.4.2.1 Introduction ....................................................................................35 3.4.2.2 ILC Interaction Region Configurations ..........................................35 3.4.2.3 Collimation Design for the ILC ......................................................36 3.4.2.4 References .......................................................................................37 3.4.3 Laser-Wire Transverse Beam Profile Monitor .............................................38 3.4.3.1 Introduction ....................................................................................38 3.4.3.2 PETRAIII Laser-Wire System .........................................................38 3.4.3.3 ATF Laser-Wire System ..................................................................39 3.4.3.4 Fibre Laser R&D ............................................................................39 3.4.3.5 References .......................................................................................40 3.4.4 Beamline Full Simulations Using BDSIM ...................................................40 3.4.4.1 Introduction ....................................................................................40 3.4.4.2 Linear Collider Applications ..........................................................41 3.4.4.3 Application to Hadronic Machines.................................................41 3.4.4.4 References .......................................................................................42 3.4.5 Fast Beam-Based Feedback Systems ............................................................42 3.4.5.1 Introduction ....................................................................................42 3.4.5.2 All-Analogue Systems .....................................................................42 3.4.5.3 Digital Systems ...............................................................................43 3.4.5.4 References .......................................................................................44 3.5 CLIC MAIN LINAC HOM WAKEFIELD SUPPRESSION THROUGH NOVEL CAVITY DESIGN ....................................................................................................................45 3.5.1 Introduction ...................................................................................................45 3.5.2 Wakefield Suppression with CLIC_DDS .....................................................46 3.5.3 Summary .......................................................................................................47 3.5.4 References .....................................................................................................47 3.6 DEVELOPMENT OF CRAB CAVITY SYSTEMS AT THE COCKCROFT INSTITUTE ...........48 3.6.1 Introduction ...................................................................................................48 3.6.2 ILC Crab Cavity Development .....................................................................48 3.6.3 CLIC Crab Cavity Development ..................................................................50 3.6.4 LHC Crab Cavity Development ...................................................................52 3.6.5 Crab Cavity LLRF System ...........................................................................53 3.6.6 Outlook ........................................................................................................59 3.6.7 References .....................................................................................................60 3.7 NEUTRINO FACTORY STUDIES .................................................................................61 5 3.7.1 Introduction .................................................................................................. 61 3.7.2 The Neutrino Factory Accelerators .............................................................. 62 3.7.2.1 Proton Driver ................................................................................. 63 3.7.2.2 Target ............................................................................................. 64 3.7.2.3 Muon Capture and Cooling ............................................................ 64 3.7.2.4 Muon Acceleration ......................................................................... 66 3.7.2.5 Muon Storage Rings ....................................................................... 68 3.7.2.6 Detector Sites ................................................................................
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