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Isodar@Kamland: a Conceptual Design Report for the Technical Facility

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Isodar@Kamland: a Conceptual Design Report for the Technical Facility IsoDAR@KamLAND: A Conceptual Design Report for the Technical Facility Abstract: This conceptual design report describes the technical facility for the IsoDAR electron- antineutrino source at KamLAND. The IsoDAR source will allow an impressive program of neutrino oscillation and electroweak physics to be performed at KamLAND. This report provides information on the physics case, the conceptual design for the subsystems, alternatives designs considered, specifics of installation at KamLAND, and identified needs for future development. We discuss the risks we have identified and our approach to mitigating those risks with this design. A substantial portion of the conceptual design is based on three years of experimental efforts and on industry experience. This report also includes information on the conventional facilities. M. Abs13, A. Adelmann20, J.R Alonso16, S. Axani16, W.A. Barletta5;16, R. Barlow11, L. Bartoszek2, A. Bungau11, L. Calabretta14, A. Calanna14, D. Campo14, G. Castro14, L. Celona14, G.H. Collin16, J.M. Conrad16, S. Gammino14, R. Johnson3, G. Karagiorgi17, S. Kayser16, W. Kleeven13, A. Kolano11, F. Labrecque3, W.A. Loinaz1, J. Minervini16, M.H. Moulai16, H. Okuno21, H. Owen8;17, V. Papavassiliou19, M.H. Shaevitz9, I. Shimizu22, T.M. Shokair15, K.F. Sorensen10, J. Spitz18, M. Toups16, M. Vagins6, K. Van Bibber4, M.O. Wascko12, D. Winklehner16, L.A Winslow16, J.J. Yang7 1Amherst College, Amherst MA, US 2Bartoszek Engineering, Aurora IL, US 3Best Cyclotron System, Inc., Springfiled VA, US 4University of California, Berkeley, CA, US 5University of California, Los Angeles, CA, US 6University of California, Irvine, CA, US 7China Institute of Atomic Energy, Beijing CN 8The Cockcroft Institute Daresbury Laboratory, Daresbury, UK 9Columbia University, New York NY, US 10 FLIBE Energy Inc., Huntsville AL, US 11University of Huddersfield, Huddersfield, UK 12 Imperial College London, London, UK 13 Ion Beam Applications, S.A., Ottignies-Louvain-la-Neuve, BE 14INFN Laboratori Nazionale del Sud, Catania, IT 15 Lawrence Livermore National Laboratory, Tracy CA, US arXiv:1511.05130v1 [physics.acc-ph] 16 Nov 2015 16Massachusetts Institute of Technology, Cambridge MA, US 17 University of Manchester, Manchester UK 18 University of Michigan, Ann Arbor MI, US 19New Mexico State University, Las Cruces NM, US 20Paul Scherrer Institute, Villigen, CH 21RIKEN Nishina Center for Accelerator-based Science, Wako, JP 22Tohoku University, Sendai, JP Corresponding Authors: Janet Conrad ([email protected]) and Mike Shaevitz ([email protected]) Contents 1 Introduction 8 2 Scientific Goals 11 2.1 Sterile Neutrino Searches . 11 2.2 Precision Electroweak Tests of the Standard Model . 13 2.3 Use of the Spectrum End Points for Physics and Calibration . 17 3 General Considerations About Cyclotrons 18 3.1 Introduction to Cyclotrons . 18 3.2 Why Choose a Cyclotron as the IsoDAR Driver? . 19 3.3 Comparison to Cyclotrons \On the Market" . 20 + 3.4 Choice of H2 Ion ................................... 21 3.5 Potentially Running Deuterons . 23 4 Conceptual Design for the IsoDAR System at KamLAND 24 4.1 Front End Design Details . 26 4.1.1 Ion Source . 26 4.1.1.1 Tests of the ECR Ion Source VIS . 27 4.1.1.2 Tests of the Multicusp Ion Source MIST-1 . 28 4.1.1.3 Risk Assessment and Mitigation . 29 4.1.2 Low Energy Beam Transport (LEBT) . 30 2 4.1.2.1 Option 1: Conventional LEBT . 31 4.1.2.2 Option 2: RFQ LEBT . 32 4.1.2.3 Risk Assessment and Risk Mitigation . 33 4.1.3 Front End - Current Status and Future Work . 34 4.2 Cyclotron Design Details . 35 4.2.1 Cyclotron Injection . 38 4.2.1.1 Spiral Inflector Design . 39 4.2.1.2 Risk Assessment & Mitigation . 41 4.2.2 Cyclotron Main Magnet . 42 4.2.2.1 Magnet Coil and Power Supply . 43 4.2.2.2 Yoke, Flux Return and Poles . 44 4.2.2.3 Magnetic Field Mapping . 46 4.2.2.4 Risk Assessment & Risk Mitigation . 47 4.2.3 Cyclotron RF System . 47 4.2.3.1 RF Cavities (Dees, Stems and Liners) . 48 4.2.3.2 RF Tuning System . 49 4.2.3.3 RF Amplifiers . 50 4.2.3.4 RF Lines and Couplers . 50 4.2.3.5 LLRF Electronics . 50 4.2.3.6 Risk Assessment & Risk Mitigation . 51 4.2.4 Vacuum System and Pumping . 51 4.2.4.1 Risk Assessment & Mitigation . 53 4.2.5 Extraction . 54 4.2.5.1 Risk Assessment & Mitigation . 55 3 4.2.6 Cyclotron Design - Current Status and Future Work . 56 4.3 Beam Transport from Cyclotron to Target (MEBT) . 57 4.3.1 Overview . 57 4.3.2 Stripping . 58 4.3.3 Basic Transport Plan . 59 4.3.4 Beamline Instrumentation and Vacuum . 62 4.3.5 Beam loss control . 62 4.3.6 Current Status and Future Work . 63 4.3.7 Risk Assessment & Mitigation . 64 4.4 Target and Shielding . 65 4.4.1 Target and Shielding Design Details . 65 4.4.1.1 Design Specifics . 65 4.4.1.2 Target Maintenance Strategies . 70 4.4.1.3 How Target Design Affects The Physics . 72 4.4.1.4 Current Status and Future Work . 73 4.4.1.5 Risk Assessment & Risk Mitigation . 74 4.4.2 Target Shielding Considerations . 75 4.4.2.1 Monte Carlo validation with experimental data . 75 4.4.2.1.1 The GEANT4 model . 76 4.4.2.1.2 Validation with experimental data and MCNPX . 76 4.4.2.2 Neutron Flux Limit Requirements . 79 4.4.2.3 Simulating Rock Activation . 81 4.4.2.3.1 Rock analysis . 81 4.4.2.3.2 Simulations . 82 4 4.4.2.4 Shielding Materials Requirements . 82 4.4.2.5 Shielding Studies . 83 4.4.2.6 Rock activation analysis . 88 4.4.2.7 Current Status and Future Work . 93 4.4.2.8 Risk assessment and Risk Mitigation . 93 4.4.3 Acquiring and Handling FLiBe . 94 4.4.3.1 Risk Assessment & Risk Mitigation . 95 4.4.4 Preliminary Mechanical Design of a Target Prototype . 96 4.5 Controls . 97 4.5.1 High Level Controls . 98 4.5.2 Low Level Controls . 98 4.5.2.1 Safety and Interlocks . 99 4.5.2.2 Interface Controls . 99 4.5.2.3 Front End Controls . 99 4.5.2.4 Cyclotron Controls . 99 4.5.2.5 MEBT Controls . 99 4.5.2.6 Target Controls . 99 4.6 Interface to Conventional Facilities . 100 4.6.1 Power Distribution . 100 4.6.2 Cooling Water System . 100 4.6.3 Additional Interfaces . 100 5 Conventional Facilities 101 5.1 Space Constraints and Civil Construction . 101 5 5.1.1 Laser Mapping of the Present KamLAND Space . 101 5.1.2 Enlarging Spaces Using Well-Understood Non-blasting Methods . 107 5.1.3 Areas where Rock Removal may be required . 108 5.1.4 Understanding Constraints Outside of the KamLAND Space . 109 5.2 Utilities . 110 5.2.1 Electrical Power . 110 5.2.2 Water Cooling . 110 5.2.3 Ventilation . 111 5.3 Radiation Protection . 112 5.3.1 Personnel Protection . 113 5.3.1.1 Prompt Radiation . 114 5.3.1.2 Residual Radiation . 114 5.3.1.3 Environmental Protection . 115 5.3.2 Interlocks . 116 6 Simulations 117 6.1 Introduction . 117 6.2 Simulation Software . 117 6.2.1 Ion Source: IGUN/KOBRA-INP/IBSimu . 117 6.2.2 Low Energy Beam Transport: WARP . 118 6.2.2.1 Main Packages (python class name in italic)........... 118 6.2.2.2 Particle Loading . 119 6.2.2.3 Fields and Lattice Elements . 119 6.2.2.4 Fieldsolvers . 120 6 6.2.2.5 Space Charge Compensation . 120 6.2.3 Cyclotron without Space Charge: OPERA . 121 6.2.4 Cyclotron with Space Charge: OPAL .................... 121 6.2.4.1 Governing Equation . 121 6.2.4.2 Self-fields . 122 6.2.4.3 External fields . 123 6.2.5 Transport to Target: TRANSPORT . 124 6.3 Simulation Results . 125 6.3.1 Ion Source and Low Energy Beam.
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