Sensitivity Key parameters: Degree of matter-antimatter symmetry violation → 

1. Magnetic spectrometer Ion source RFQ Beam chopper Diagnostics LEBT 20 metres The UKNeutrino FactoryProject • Neutrino oscillations • A neutrino created as one ‘type’ or ‘flavour’ changes into another type as it travels: • Implications for particle physics: • Neutrinos are massive and mix: Standard Model is incomplete • Neutrinos may violate matter-antimatter symmetry • Impact on astrophysics and cosmology: • Origin of matter-dominated universe • Contribution to dark matter known to exist in universe • Require dedicated experimental programme to: • Search for matter-antimatter symmetry violation • Precisely measure parameters • Sensitivity • Key parameters: • Degree of matter-antimatter symmetry violation →  • Degree of mixing e- and -neutrinos →13 • Neutrino Factory has highest sensitivity UK Neutrino Factory collaboration D. Rodger, H.C. Lai, F. RobinsonApplied Electromagnetics Research Group, Electronic and Electrical Engineering Department, University of Bath, Claverton Down, Bath, Avon BA2 7AY, UK N.K. Bourne, A. MilneCranfield University, Royal Military College of Science, Shrivenham. Swindon, SN6 8LA, UK M.W. PooleAccelerator Science and Technology Centre, Daresbury Laboratory, Daresbury, Warrington, Cheshire, WA4 4AD, UK D. WilcoxHigh Power RF Faraday Partnership, c/o Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire, OX11 0QX, UK A.T. Doyle, F. J. P. SolerDepartment of Physics and Astronomy, Kelvin Building, The University of Glasgow, Glasgow, G12 8QQ, UK P. Cooke, J. B. Dainton, J. R. Fry, R. Gamet, Ch. TouramanisDepartment of Physics, University of Liverpool, Oxford St, Liverpool L69 7ZE, UK G. Barber, P. Dornan, M. Ellis, K. Long†, D.R. Price, J. Sedgbeer, A. TapperImperial College London, Prince Consort Road, London SW7 2BW, UK G.D. Barr, J.H. Cobb, S. Cooper, G. Wilkinson, Subdepartment of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, UK H. JonesSubdepartment of Condensed Matter Physics, University of Oxford, Department of Physics, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, UK G. Bellodi, J.R.J. Bennett, S. Brooks, M.A. Clarke-Gayther, C. Densham, P.V. Drumm, R. Edgecock, D.J.S. Findlay, F. Gerigk, A.P. Letchford, P.R. Norton, C.R. Prior‡, G. Rees, J.W.G. Thomason, J.V. TrotmanCCLRC Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire, OX11 0QX, UK P.F. HarrisonDepartment of Physics, Queen Mary University of London, Mile End Road, London, E1 4NS C. N. Booth, E. Daw, P. HodgsonDepartment of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, UK  and Fluid Gravity Engineering, 83 Market St., St. Andrews, Fife  and e2v technologies, 106 Waterhouse Lane, Chelmsford, Essex CM1 2QU, UK R109 Near Detector Schematic of the UK Neutrino Factory Design The UK is playing a significant role in the international design effort towards a neutrino factory. RFQ (Radio Frequency Quadrupole) LEBT (Low Energy Beam Transport) H−Ion Source FFAG II (8-20GeV) Beam Chopper So far, four key areas have been identified in which R&D is particularly important: these are highlighted on this diagram and detailed elsewhere in FFAG III (20-50GeV) 180MeV DTL (Drift Tube Linac) the presentation. Most of the technology demonstrations will be constructed within the next five years. Achromat for removing beam halo Muon Decay Ring (muons decay to neutrinos) To Far Detector 1 Proton Driver Front-End Test Stand at RAL Any accelerator complex must start with a particle source (in this case H− ions) and a sequence of components that are either tailored for low-energy beam trans- port and acceleration (LEBT, RFQ), or perform functions that are most effectively done at low energy (the chopper). The specification of a proton driver for a neutrino factory demands that these components push the envelope of high beam current with very low uncontrolled losses. RAL has an active ion source research programme and a chopper development project running in parallel with CERN. FFAG Electron Model at Daresbury An unconventional kind of accelerator called a non-scaling FFAG is being devised to accelerate the muons rapidly enough before they decay. To verify this technology, a scaled model using electrons instead of muons is being designed for operation at Daresbury Laboratory, where synergies with existing electron machines can make it particularly cost-effective. FFAG I (2-8GeV) • Two Stacked Proton Synchrotrons (full energy) • 6GeV • 78m mean radius • Each operating at 25Hz, alternating for 50Hz total To Far Detector 2 Target enclosed in 20Tesla superconducting solenoid (produces pions from protons) Proton Beam Dump Solenoidal Decay Channel (in which pions decay to muons) Stripping Foil (H- to H+/protons) • Two Stacked Proton Synchrotrons (boosters) • 1.2GeV • 39m mean radius • Both operating at 50Hz RF Phase Rotation Muon Linac to 2GeV (uses solenoids) UK Neutrino Factory collaboration Muon Ionisation Cooling Experiment (MICE) The muon beam must be ‘cooled’, or reduced in size, to fit inside the accelerators downstream. MICE uses a muon beam from an intermediate target of the ISIS accelerator at RAL to prove the practicality of a technique called ionisation cooling, which is unique to muons. The international MICE collaboration are showing two posters here. Muon Cooling Ring UK Targetry R&D Programme The target must survive an extreme degree of heating: dissipating 1MW of heat at temperatures reaching over 2000°C, while having to withstand physical shocks caused by 50 proton pulses per second. RAL is working with the RMCS at Cranfield University to investigate these phenomena. • Proton bunches compressed to 1ns duration at extraction • Mean power 5MW More about the front-end test stand, which will be an integrated demonstration of all these low-energy technologies, can be found below. • Pulsed power 16TW Target Studies CCLRC - Imperial - Warwick Front End Test Stand Parameters of the NF Target Proton Beam pulsed 10-50 Hz pulse length 1-2 ms energy 2-30 GeV average power ~4 MW Target (not a stopping target) mean power dissipation 1 MW energy dissipated/pulse 20 kJ (50 Hz) energy density 0.3 kJ/cm3 The target operates at very high mean power dissipation and extremely high energy density. This high power density creates severe problems in dissipating the heat and the short pulses produce thermal shocks due to the rapid expansion of the target material. These shocks can potentially exceed the mechanical strength of solid materials. In addition the pions and muons created in the target must be collected in a 20 Tesla solenoidal field or a magnetic horn. This imposes strong restraints on the target and collector system which must ultimately be designed as a single entity. What? An experimental facility to test the all-important early stages of high power proton accelerators (HPPAs). High power proton accelerators are the bases of spallation neutron sources, transmutation machines, and neutrino factories. Why? Because high power proton accelerators must produce high quality megawatt beams with beam losses of less than 0.0001% per metre, and such high quality beams have yet to be demonstrated. Where? At Rutherford Appleton Laboratory in Oxfordshire. When? Design already under way. Construction starts 2005. The test stand will consist of an H– ion source producing 60 mA, 2 ms pulses at 50 pps, a LEBT running at 75 keV to match the beam from the ion source into the RFQ, an RFQ accelerator driven by a 1–2 MW, 234 MHz RF driver to increase the beam energy to 2.5 MeV, a beam chopper switching between beam bunches in 2 ns, and a comprehensive suite of diagnostics to measure beam currents, emittances, energy distributions and bunch structures. The design of the test stand involves much sophisticated physics design, and the construction involves challenging electrical, electronic, mechanical, RF and vacuum engineering, together with the procurement of much high-tech apparatus. beam 2 cm 20 cm Several targets which potentially can withstand the huge power density are currently being considered worldwide: a. Mercury (or a liquid metal) jets b. Contained flowing mercury (or a liquid metal) c. Solid target - tantalum rotating toroid, thermally radiating at ~2300 K d. Granular solid target The UK is currently investigating solid targets. The solid target is simple in concept, but may be susceptible to shock damage. There are many examples of solids bombarded by proton beams at similar power densities and even targets operating at an order of magnitude higher power density have been shown to survive many pulses. Shock studies are the main thrust of the UK activity. A toroid or band, rotating in vacuum and thermally radiating its power to water-cooled vacuum chamber walls could provide a simple, clean and reliable high power target. It would not require beam windows between the incoming proton beam and the outgoing pion beam. It is proposed to consider electromagnetic levitation and guidance of the toroid and rotation by linear motors, so that there are no moving parts (except for the toroid) in the vacuum and no physical contact with the toroid. rotating toroid toroid magnetically levitated and driven by linear motors solenoid magnet toroid at 2300 K radiates heat to water-cooled surroundings proton beam Schematic diagram of the radiation cooled rotating toroidal target