Neutrino 2004 Paris Alain Blondel, 17/6/04 Physics with a Neutrino Factory Complex -- Principles -- performance -- other physics and muon collider -- R&D in Europe and elsewhere This summarizes the work of several 100 authors who recently published 'ECFA/CERN studies of a European Neutrino Factory Complex' CERN ECFA/04/230 and of the US-based Muon Collaboration (S. Geer & R. Palmer et al)

Neutrino 2004 Paris Alain Blondel, 17/6/04 1.We know that there are three families of active, light neutrinos (LEP) 2.Solar neutrino oscillations are established (Homestake+Gallium+Kam+SK+SNO+KamLAND) 3.Atmospheric (   ) oscillations are established (IMB+Kam+SK+Macro+Sudan+K2K) 4.At that frequency, electron neutrino oscillations are small (CHOOZ) This allows a consistent picture with 3-family oscillations    ~30 0  m 12 2 ~ eV 2    ~45 0  m 23 2 ~ eV 2    ~ 10 0 with several unknown parameters    mass hierarchy Where are we? *)to set the scale: CP violation in quarks was discovered in 1964 and there is still an important program (K0pi0, B-factories, Neutron EDM, LHCb, BTeV….) to go on for >>10 years…i.e. a total of >50 yrs. and we have not discovered leptonic CP yet! 5. LSND ? (  miniBooNe) This result is not consistent with three families of neutrinos oscillating, and is not supported (nor is it completely contradicted) by other experiments. If confirmed, this would be even more exciting See Barger et al PRD Where do we go? leptonic CP & T violations => an exciting experimental program for at least 25 years *)

Neutrino 2004 Paris Alain Blondel, 17/6/04 -- Neutrino Factory -- CERN layout    e + e   _ interacts giving   oscillates e     interacts giving    WRONG SIGN MUON p/ s  s =  yr e  yr   yr  yr

Neutrino 2004 Paris Alain Blondel, 17/6/04 MEASUREMENTS at - FACTORY

Neutrino 2004 Paris Alain Blondel, 17/6/04 Detector zIron calorimeter zMagnetized yCharge discrimination yB = 1 T zR = 10 m, L = 20 m zFiducial mass = 40 kT Baseline 3500 Km 732 Km 3.5 x x x x x x 10 5  CC e CC  signal (sin 2  13 =0.01) Events for 1 year Also: L Arg detector: magnetized ICARUS Wrong sign muons, electrons, taus and NC evts *-> CF e signal at J-PARC =40

6 Oscillation parameters can be extracted using energy distributions a)right-sign muons b)wrong-sign muons c)electrons/positrons d)positive  -leptons e)negative  -leptons f)no leptons X2 (  + stored and  - stored) Events Bueno, Campanelli, Rubbia; hep-ph/ Simulated distributions for a 10kt LAr detector at L = 7400 km from a 30 GeV nu-factory with  + decays. E VIS (GeV) Note: e   is specially important (Ambiguity resolution & Unitarity test): Gomez-Cadenas et al.

Neutrino 2004 Paris Alain Blondel, 17/6/04 Linder et al. Above plot obtained with Golden channel, one sign only and one distance. Emphasizes very low systematics, and degeneracies

Neutrino 2004 Paris Alain Blondel, 17/6/04 Neutrino fluxes  + -> e + e   / e ratio reversed by switching     e   spectra are different No high energy tail. Very well known flux (aim is ) - absolute flux measured from muon current or by  e  ->   e in near expt. -- in triangle ring, muon polarization precesses and averages out (preferred, -> calib of energy, energy spread) -- E&   calibration from muon spin precession -- angular divergence: small effect if  < 0.2/  can be monitored -- in Bow-tie ring, muon polarization stays constant, no precession 20% easy -> 40% hard Must be measured!!!! (precision?) Physics gain not large  polarization controls e flux:  + -X> e in forward direction

Neutrino 2004 Paris Alain Blondel, 17/6/04

CP asymmetries compare e   to e   probabilities   is prop. to matter density, positive for neutrinos, negative for antineutrinos HUGE effect for distance around 6000 km!! Resonance around 12 GeV when  m 2 23 cos2  13   = 0

Neutrino 2004 Paris Alain Blondel, 17/6/04 CP violation (ctd) Matter effect must be subtracted. One believes this can be done with uncertainty Of order 2%. Also spectrum of matter effect and CP violation is different  It is important to subtract in bins of measured energy.  knowledge of spectrum is essential here! 5-10 GeV GeV GeV GeV GeV 40 kton L M D 50 GeV nufact 5 yrs  /yr In fact, GeV Is enough! Best distance is km e.g. Fermilab or BNL -> west coast or …

Neutrino 2004 Paris Alain Blondel, 17/6/04 Bueno, Campanelli, Rubbia hep-ph/

Neutrino 2004 Paris Alain Blondel, 17/6/04 channel at neutrino factory High energy neutrinos at NuFact allow observation of  e   (wrong sign muons with missing energy and P  ). UNIQUE Liquid Argon or OPERA-like detector at 732 or 3000 km. Since the sin  dependence has opposite sign with the wrong sign muons, this solves ambiguities that will invariably appear if only wrong sign muons are used. ambiguities with only wrong sign muons (3500 km) equal event number curves muon vs taus associating taus to muons (no efficencies, but only OPERA mass) studies on-going A. Donini et al   

Neutrino 2004 Paris Alain Blondel, 17/6/04 e.g. Rigolin, Donini, Meloni

Neutrino 2004 Paris Alain Blondel, 17/6/04 Wrong sign muons alone Wrong sign muons and taus Wrong sign muons and taus + previous exp.

Neutrino 2004 Paris Alain Blondel, 17/6/04 red vs blue = different baselines dashed vs line = different energy bin (most powerful is around matter ~12 GeV) red vs blue = muons and taus

Neutrino 2004 Paris Alain Blondel, 17/6/04 Conclusion: Neutrino Factory has many handles on the problem (muon sign + Gold + Silver + different baselines + binning in energy ) thanks to high energy! "It could in principle solve many of the clones for    down to 1 0 The most difficult one is the octant clone which will require a dedicated analysis" (Rigolin)

Neutrino 2004 Paris Alain Blondel, 17/6/04 Where will this get us… 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 kt water Fréjus (J-PARC phase II similar) Neutrino Factory with 40 kton large magnetic detector Mezzetto X 5

Neutrino 2004 Paris Alain Blondel, 17/6/04 Superbeam only Beta-beam only Betabeam + superbeam 3 sigma sensitivity of various options NUFACT

Neutrino 2004 Paris Alain Blondel, 17/6/04 T asymmetry for sin  = JHFI-SK ! asymmetry is a few % and requires excellent flux normalization (neutrino fact., beta beam or off axis beam with not-too- near near detector ) JHFII-HK neutrino factory NOTE: This is at first maximum! Sensitivity at low values of  13 is better for short baselines, sensitivity at large values of  13 may be better for longer baselines (2d max or 3d max.) This would desserve a more systematic analysis! stat.error

Neutrino 2004 Paris Alain Blondel, 17/6/04 Could begin as soon as SPL/accumulator is build: -High intensity low energy muon experiments -- rare muon decays and muon conversion (lepton Flavor violation) -- G F, g-2, edm, muonic atoms, e +    e -   --> design of target stations and beamlines needed. - 2d generation ISOLDE (Radioactive nuclei) -- extend understanding of nuclei outside valley of stability -- muonic atoms with rare nuclei(?) if a sufficient fraction of the protons can be accelerated to E>15 GeV: -High intensity hadron experiments -- rare K decays (e.g.K->    ) In parallel to long baseline neutrino experiments: -short baseline neutrino experiments (standard fluxes X10 4 ) -- DIS on various materials and targets, charm production -- NC/CC -> m w (10-20 MeV)  e   e & e e  e e -> sin 2  w eff ( ) --> design of beamline + detectors needed Other physics opportunities at a -factory complex Related to high intensity

Neutrino 2004 Paris Alain Blondel, 17/6/04 -- Neutrino Factory -- Short baseline Physics    e + e   _ p/ s  s =  yr e  yr   yr  yr Vey near detector station

Neutrino 2004 Paris Alain Blondel, 17/6/04 At the end of the straight sections, the fluxes are gigantic, in a very small area:

Neutrino 2004 Paris Alain Blondel, 17/6/04

preset best:

Neutrino 2004 Paris Alain Blondel, 17/6/04 1 m Z 4 1 m W 4

Neutrino 2004 Paris Alain Blondel, 17/6/04 other combinations? (probably better to keep separately NC, Cc e CC  and fit)

Neutrino 2004 Paris Alain Blondel, 17/6/04 Another example: the extraction of  s(x) and  d v (x) Sudoh and Morii suggested to extract it from the  c polarization (imagine placing a typical hadronic charm experiment with a polarized H2 proton target in a 20 cm diameter neutrino beam)

Neutrino 2004 Paris Alain Blondel, 17/6/04 sensitive to polarized s quark distribution and valence d-quark distribution

Neutrino 2004 Paris Alain Blondel, 17/6/04 From neutrino factory to Higgs collider        h (115) Upgrade to 57.5 GeV Separate   &  , add transfer lines More cooling +  E /E reduction Muon collider: a small…. but dfficult ring

Neutrino 2004 Paris Alain Blondel, 17/6/04 Higgs factory      h(115) - S-channel production of Higgs is unique feature of Muon collider - no beamstrahlung or Synch. Rad., g-2 precession => outstanding energy calibration (OK) and resolution R=  E/E (needs ideas and R&D, however!)  m h =0.1 MeV  h =0.3 MeV  h->bb /  h = 1% very stringent constraints on Higgs couplings (  b)

Neutrino 2004 Paris Alain Blondel, 17/6/04

Higgs Factory #2:      H, A SUSY and 2DHM predict two neutral heavy Higgs with masses close to each other and to the charged Higgs, with different CP number, and decay modes. Cross-sections are large. Determine masses & widths to high precision. Telling H from A: bb and tt cross-sections (also: hh, WW, ZZ…..) investigate CP violating H/A interference.

Neutrino 2004 Paris Alain Blondel, 17/6/04 Neutrino Factory studies and R&D USA, Europe, Japan have each their scheme. Only one has been costed, US study II: Neutrino Factory CAN be done…..but it is too expensive as is. Aim: ascertain challenges can be met + cut cost in half. + detector: MINOS * 10 = about 300 M€ or M$

Neutrino Factory Concept Make as many charged pions as possible INTENSE PROTON SOURCE (In practice this seems to mean one with a beam power of 4 MW) 2.Capture as many charged pions as possible Low energy pions Good pion capture scheme 3. Capture as many daughter muons as possible within an accelerator Reduce phase-space occupied by the  s Muon cooling 4. Accelerate FAST! Example: US Design Study 2 NB. Energy of proton source not so relevant 2-50 GeV considered

Neutrino Factory Concept UK Design Fast cycling synchrotron Japanese Design J-PARC based

40 Why we are optimistic/enthusiastic – US perspective: We are working towards a “World Design Study” with an emphasis on cost reduction. Note: In the Study 2 design roughly ¾ of the cost came from these 3 roughly equally expensive sub-systems. New design has similar performance to Study 2 performance but keeps both  + and  - ! S. Geer: Good hope for improvement in performance ad reduction of cost!

Neutrino 2004 Paris Alain Blondel, 17/6/04 MUTAC ( jan 2003)(US) The committee remains convinced that this experiment, which is absolutely required to validate the concept of ionization cooling, and the R&D leading to it should be the highest priority of the muon collaboration. Planning and design for the experiment have advanced dramatically(…) EMCOG: (6 feb 2003) (Europe) (…)EMCOG was impressed by the quality of the experiment, which has been well studied, is well organized and well structured. The issue of ionization cooling is critical and this justifies the important effort that the experiment represents. EMCOG recommends very strongly a timely realization of MICE. MUTAC: Muon Technical Advisory Committee (Helen Edwards, et al) (US) EMCOG: European Muon Coordination and Oversight Group (C. Wyss et al) ECFA recommendations (September 2001:)

Neutrino 2004 Paris Alain Blondel, 17/6/04 The four priorities set up by EMCOG (European Muon Coordination and Oversight Group) -- High intensity proton driver (SPL; etc..) -- High power target -- high rep rate collection system (horns, solenoid) -- Ionization coolng demonstration These will correspond to the workpackages of the ECFA/ESGARD superbeam/neutrino factory feasibility study

Neutrino 2004 Paris Alain Blondel, 17/6/04 Conclusions 1. the Neutrino Factory remains the most powerful tool imagined so far to study neutrino oscillations High energy e   and  e   transitions 2. The complex offers many other possibilities 3. It is a step towards muon colliders 4. There are good hopes to reduce the cost significantly 5. Regional and International R&D o components and R&D experiments are being performed by an enthusiastic and motivated community 6. Opportunities exist in Europe: HI proton driver, Target CERN Collector RAL