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Future Neutrino Oscillation Experiments: towards a world-wide design study . An I nternational S coping S tudy of a Neutrino Factory and super-beam facility. 0. neutrino physics is REALLY exciting! massive neutrinos open the possibility of lepton number violation
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Future Neutrino Oscillation Experiments: towards a world-wide design study An International Scoping Studyof a Neutrino Factory and super-beam facility
0. neutrino physics is REALLY exciting! massive neutrinos open the possibility of lepton number violation and LEPTONIC CP/T violation leptogenesis 1. An ambitious neutrino programme is a distinct possibility, but it must be well prepared to have a good proposal in time for the big decision period in 2010 (Funding window: 2011-2020) 2. Two avenues have been identified as promising a) SuperBeam + Beta-Beam + Megaton detector (SB+BB+MD) b) Neutrino Factory (NuFact) + magnetic detector (40kton) The physics abilities of the neutrino factory are (much) superior but….. « what is the realistic time scale? » 3. (Hardware) cost estimate of a neutrino factory ~1B€ + detectors. This needs to be verifed and ascertained on a localized scenario (CERN, RAL…) and accounting. The cost of a (BB+SB+MD) is not very different, though perhaps lower, but more uncertain. Cost/physics performance/feasibility comparison needed ‘ECFA/CERN studies of a European Neutrino Factory Complex' CERN 2004-002 ECFA/04/230 and Physics with a MMW proton driver (MMW workshop) CERN-SPSC-2004-024
systematics . ……………………………………degeneracies correlations approval date: b-beam + SPL3.5 SB+Mton Lindner et al newer plot should come out of NUFACT05 and scoping study
The Beta-beam accelerator study is funded within EURISOL DESIGN STUDY and this is making impressive progress. (it is still a very new concept however) The Neutrino Factory and Superbeam design study (with RAL as home institute) was prepared for a EU DS call in 2004 (sub march 2005) which never took place. It turned out to be too far-fetched to substitute an I3 proposal to this. In the process the need to include detector R&D was identified. Meanwhile… Optimization of the neutrino factory in the US has led to cost reduction by 40% The target experiment nTOF11 is now approved at CERN scheduled to run in 2007 The MICE experiment is now approved at RAL (+recognized as CERN RE11) and scheduled to run in 2007 (further contributions from continental Europe would be welcome!) There is a funded UK neutrino factory collaboration There is a proposal for an electron-model FFAG experiment
The NF concept design is not unique -- Japan scenario (FFAG-based with ongoing R&D) -- US scenario (based on multi-bunching of muons and 200 MHz RF) -- CERN scenario (based on mono-bunching of muons and 88 MHz RF) Each scenario has advantages. MICE and the target experiment nTOF11 are based on US scenarios, which is more thoroughly (end-to-end) studied. need to define an optimization/choice process and a baseline for study
WORLD WIDE STUDY: 1. It is likely that there will be no more than one Megaton detector and/or one Neutrino Factory in the world so we better agree on what we want. 2. Expertise on Neutrino Factory is limited world wide (mostly in US) 3. Resources e.g. at CERN are also very limited 4. International community meets regularly at NUFACT meetings and is engaged in common projects (R&D experiments) and agreed at NUFACT03 that a World Wide design study would be necessary
Scoping study • Design study should take place in two phases • Scoping study: understand what are the most important parameters • of the facility to be studied, what are the critical tests to be performed, • and how to organize it. Assemble the team. • 2. Design study: proceed to the design study and associated R&D experiments, • with the aim to deliver a CDR that a laboratory can chose as its next project. By letter of 4 March 2005 Pr. John Wood CEO of CCLRC requested plans for a scoping study:
letter from John Wood to Ken Long(UK neutrino factory) 4/3/2005
Collaborators of the scoping study: -- ECFA/BENE working groups (incl. CERN) -- Japanese Neutrino Factory Collaboration -- US Muon Collaboration -- UK Neutrino Factory Collaboration The outputof the scoping study will be a report in which: · The physics case for the facility is defined; · A baseline design for the accelerator complex, or, for some subsystems, the programme required to arrive at a baseline design, is identified; · The baseline designs for the neutrino detection systems are identified; and · The research-and-development programme required to deliver the baseline design is described. objectives · Evaluate the physics case for a second-generation super-beam, a beta-beam facility and the Neutrino Factory and to present a critical comparison of their performance; · Evaluate the various options for the accelerator complex with a view to defining a baseline set of parameters for the sub-systems that can be taken forward in a subsequent conceptual-design phase; and to · Evaluate the options for the neutrino detection systems with a view to defining a baseline set of detection systems to be taken forward in a subsequent conceptual-design phase.
to be formed Peter Dornan(London) Yohiyiro Nagashima (Osaka) Alain Blondel Michael Zisman (Berkeley) freshly nominated by the wise men!
Physics compare performance of various options on equal footing of parameters and conventions and agreed standards of resolutions, simulation etc. identify tools needed to do so (e.g. Globes upgraded) propose « best values » of baselines, beam energies etc.. Detectors (NEW!) Water Cherenkov (1000kton) Magnetized Iron Calorimeter (50kton) Low Z scintillator (100 kton) Liquid Argon TPC (100 kton) Hybrid Emulsion (4 kton) Near detectors (and instrumentation) Accelerator: -- proton driver (energy, time structure and consequences) -- target and capture (chose target and capture system) -- phase rotation and cooling -- acceleration and storage evaluate economic interplays and risks include a measure of costing and safety assessment
Time scales: NUFACT05 (Sunday 26 June 2005) launch of scoping study September 2005: ISS report0 NUFACT06 (summer 2006) discussion of results of scoping study September 2006 ISS report 2007 full design study proposal 2010 conclusions of Design Study & CDR NB: This matches well the time scales set up at CERN – participation of CERN is highly desirable to ensure that the choices remain CERN-compatible.
We would like to thank ECFA for its continuous support since 1998!. We are hopefully starting a process by which a credible and reliably costed experimental facilitycan be designed, so that a laboratory can chose it as its next project within a reasonable time scale (2010) We believe that the physics prospects make enterprise highly worthwhile. For the European partners, one important purpose of the scoping study is to prepare a powerful bid for a Design Study proposal under EU-FP7. The success of this enterprise will largely depend on the matching support of European laboratories and funding agencies. To this effect we would like to request a strong endorsement by ECFA, which we believe will be highly significant.
CERN-SPL-based Neutrino SUPERBEAM 300 MeV n m Neutrinos small contamination from ne (no K at 2 GeV!) target! Fréjus underground lab. A large underground water Cherenkov (400 kton) UNO/HyperK or/and a large L.Arg detector. also : proton decay search, supernovae events solar and atmospheric neutrinos. Performance similar to J-PARC II There is a window of opportunity for digging the cavern stating in 2009 (safety tunnel in Frejus)
CERN: b-beam baseline scenario Nuclear Physics neutrinos of Emax=~600MeV SPL target! Decay ring B = 5 T Lss = 2500 m SPS Decay Ring ISOL target & Ion source ECR Cyclotrons, linac or FFAG Stacking! Rapid cycling synchrotron PS Same detectors as Superbeam !
Combination of beta beam with low energy super beam Unique to CERN: need few 100 GeV accelerator (PS + SPS will do!) experience in radioactive beams at ISOLDE many unknowns: what is the duty factor that can be achieved? (needs < 10-3 ) combines CP and T violation tests e m (+) (T) m e (p+) (CP) e m (-) (T) m e (p-) • Can this work???? theoretical studies now on beta beam • design study together with EURISOL + SPL target and horn R&D
Superbeam+Betabeam option • What is the importance of the superbeam in this scheme? • T violation? • increased sensitivity? • have a (known) source of muon neutrinos for reference? • 2. At which neutrino energy can one begin to use the event energy distribution? • Fermi motion and resolution issues. • What is the impact of muon Cherenkov threshold? • What is the best distance from the source? What is the effect of changing the • beta-beam and superbeam energy?(event rates, backgrounds, ability to use dN/dE ) • Should energy remain adjustable after the distance choice? • 4, what is the relationship between beta-beam energy vs intensity? • 5. What is really the cost of the detector? • what PM coverage is needed as function of energy and distance. NB superbeam requires 4 MW proton driver, beta-beam claim to be able to live with 200 kW!
-- Neutrino Factory -- CERN layout -- cooling! 1016p/s target! acceleration! 1.2 1014 m/s =1.2 1021 m/yr _ 0.9 1021 m/yr m+ e+ne nm 3 1020 ne/yr 3 1020 nm/yr oscillates ne nm interacts givingm- WRONG SIGN MUON interacts giving m+
Questions for Neutrino Factory experiments: • Do we REALLY NEED TWO far locations at two different distances? • 3000 km 1st osc. max at 6 GeV and 2d max at 2 GeV. Muon momentum cut at 4 GeV cuts 2d max info. Can this be improved? • Can we eliminate all degenracies by combination of energy distribution and analysis of different channels (tau, muon, electron, both signs, NC…) • what are the systematics on flux control? (CERN YR claims 10-3) • 5. optimal muon ENERGY? Cost of study II was 1500M$ + 400M$*E/20
4. issues to be solved -- include superbeam in the study? capture with horns (compatible) vs solenoid (not) -- proton energy vs repetition rate of the complex -- monobunching (CERN) or polybunching (US)? -- muon acceleration: Linac, RLAs, FFAG? -- cooling vs accelerator aperture? -- detectors: Magnetic detector(segmentation?) vs liquid argon and vs tau detector? feasible size? cost vs performance? locations? Impacts on desired intensity and energy of the muon beam synergies with (SB+BB+MT) detectors?
From Mauro Mezzetto: Regarding the comparisons, in my view we are still missing a lot of pieces: -- A stable realistic setup for NuFact: muon energy, muon fluxes, baselines, golden+golden, golden+silver, Icarus like etc. -- A stable realistic setup for beta beam: optimal gamma, fluxes, baseline -- A detailed study of detector performances. For water we have parameters from SK. For the magnetic detector we should have Minos parameters. For emulsions and liquid argon we should have Opera and Icarus. This topic could be named « build a set of Globes AEDL files describing detector performances in the most accurate possible way ». -- A realistic and accepted set of measured parameters at the time when the future facilities will start. It makes no sense to assume we will not know the precise value of the atmospheric parameters in 10 years from now, it should be agreed the level of precision of the solar parameters after the end of SNO and Kamland (and hopefully Borexino). This topic is far from trivial because additional and new analysis from atmospherics, data for Nova if any etc. could help very much in solving degeneracies. -- A study of performances using the same set of assumptions: systematic errors, degeneracies, ambiguities etc. This can be done already now by using Globes, and I'm consuming my time in trying to use it.
We are working towards a “World Design Study” with an emphasis on cost reduction. $$$$$ … COST … $$$$$ 27 Why we are optimistic: In the previous design ~ ¾ of the cost came from these 3 equally expensive sub-systems.New design has similar performance to Study 2 performance and keeps both m+ and m- ! (RF phase rotation) NUFACT 2004: cost can be reduced by at least 1/3 = proton driver + 1 B € MAYBE the Neutrino Factory is not so far in the future after all…. S. Geer:
Where will this get us… X 5 0.10 130 2.50 50 10 Mezzetto comparison of reach in the oscillations; right to left: present limit from the CHOOZ experiment, expected sensitivity from the MINOS experiment, CNGS (OPERA+ICARUS) 0.75 MW JHF to super Kamiokande with an off-axis narrow-band beam, Superbeam: 4 MW CERN-SPL to a 400 kton water Cerenkov in Fréjus (J-PARC phase II similar) from a Neutrino Factory with 40 kton large magnetic detector.
! asymmetry is a few % and requires excellent flux normalization (neutrino fact., beta beam or off axis beam with not-too-near near detector) T asymmetry for sin = 1 neutrino factory JHFII-HK JHFI-SK NOTE: This is at first maximum! Sensitivity at low values of q13 is better for short baselines, sensitivity at large values of q13 may be better for longer baselines (2d max or 3d max.) This would desserve a more careful analysis! 10 30 0.10 0.30 90
3 sigma sensitivity of various options Superbeam only Beta-beam only Betabeam + superbeam NUFACT