1. Sensitivity Key parameters: ― Degree of matter-antimatter symmetry violation →  ― Degree of mixing e- and  -neutrinos →  13 Neutrino Factory has highest sensitivity 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 H − Ion Source LEBT (Low Energy Beam Transport) RFQ (Radio Frequency Quadrupole) Beam Chopper 180MeV DTL (Drift Tube Linac) Stripping Foil (H - to H + /protons) Achromat for removing beam halo Two Stacked Proton Synchrotrons (boosters) 1.2GeV 39m mean radius Both operating at 50Hz Two Stacked Proton Synchrotrons (full energy) 6GeV 78m mean radius Each operating at 25Hz, alternating for 50Hz total Proton bunches compressed to 1ns duration at extraction Mean power 5MW Target enclosed in 20Tesla superconducting solenoid (produces pions from protons) Proton Beam Dump Solenoidal Decay Channel (in which pions decay to muons) RF Phase Rotation Target Studies Parameters of the NF Target Proton Beam pulsed10-50 Hz pulse length1-2 ms energy 2-30 GeV average power ~4 MW Target (not a stopping target) mean power dissipation1 MW energy dissipated/pulse20 kJ (50 Hz) energy density0.3 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. 2 cm 20 cm beam 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 rotating toroid proton beam solenoid magnet toroid at 2300 K radiates heat to water-cooled surroundings toroid magnetically levitated and driven by linear motors 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. Schematic diagram of the radiation cooled rotating toroidal target Muon Cooling Ring FFAG I (2-8GeV) FFAG II (8-20GeV) FFAG III (20-50GeV) R109 Near Detector Muon Decay Ring (muons decay to neutrinos) To Far Detector 2 To Far Detector 1 Muon Linac to 2GeV (uses solenoids) Schematic of the UK Neutrino Factory Design The UK is playing a significant role in the international design effort towards a neutrino factory. 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. 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. Pulsed power 16TW 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. CCLRC - Imperial - Warwick Front End Test Stand 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. RFQBeam chopperDiagnostics LEBT Ion source Magnetic spectrometer 20 metres 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 the presentation. Most of the technology demonstrations will be constructed within the next five years. More about the front-end test stand, which will be an integrated demonstration of all these low-energy technologies, can be found below. 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. The UK Neutrino Factory Project UK Neutrino Factory collaboration D. Rodger, H.C. Lai, F. Robinson Applied 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. Poole Accelerator 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. Soler Department 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. Touramanis Department 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. Tapper Imperial 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. Jones Subdepartment 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. Trotman CCLRC Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire, OX11 0QX, UK P.F. Harrison Department of Physics, Queen Mary University of London, Mile End Road, London, E1 4NS C. N. Booth, E. Daw, P. Hodgson Department 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