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Future neutrino oscillation experiments. J.J. Gómez-Cadenas U. Valencia/KEK Original results presented in this talk based on work done in collaboration with P. Hernández, J. Burguet-Castell, E. Couce, and D. Casper. A trip to terra incognita. Evidence of oscillations. KAMLAND.
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Future neutrino oscillation experiments J.J. Gómez-Cadenas U. Valencia/KEK Original results presented in this talk based on work done in collaboration with P. Hernández, J. Burguet-Castell, E. Couce, and D. Casper
A trip to terra incognita Evidence of oscillations KAMLAND T2KII+BB+NF T2K-NOVA K2K/Minos/CNGS Evidence of oscillations
1 mm t n Pb Emulsion layers
The last anomaly • LSND • Does not fit in a 3 family scenario • 2 m2 • MiniBooNE (Fnal ) • Testing it … • If it is confirmed (2005)!? • Change our vision of • (has happened before…)
Oscillations in 3D Solar data. The ne is oscillating (via enhanced matter resonance, MSW) to the other two flavours with Dm1210-4 eV2, q12 300 Atmospheric data. Largely nmnt (vacuum) oscillations with Dm2310-3 eV2q23 450 Two mass differences need 3 neutrinos
Neutrino oscillation physics: you are here CP violation phase atmospheric solar Links atmospheric & solar sectors Observed by Super-Kamiokande, confirmed by K2K. CNGS+NUMI will measure parameters to about 20-30 % q13 limited by CHOOZ to be smaller than about 100. Nothing known about d. Observed by 30 years of solar neutrinos experiments, nailed down by SNO and Kamland. Parameters known at 10%
The quest What is the value of q13? What is the value of d? Is there CP violation? Which mass spectrum?
q13: link between atmospheric and solar oscillations solar solar atmospheric interference
Sensitivity to q13: subleading transitions Subleading: nenm, ne nt: sensitive to q13 and d Leading: nm nt : rather insensitive to q13 and d
CP violation in n oscillations CP violation in n oscillations Oscillation probability is different for neutrinos and antineutrinos. Thus, one can measure non-vanishing asymmetries ACP
Determine mass spectrum • The same experiments that will measure d and q13 can establish the n mass hierarchy by studying the matter effects on Earth • One gets a large amplification/supression of P(ne nm) depending on whether the hierarchy is “natural” or “inverted”
Measurement of q13. Correlations The appearance probability P(q13,d) obtained for neutrinos at fixed (E,L) with input parameters (q13,d) has no unique solution. Indeed the equation: has a continuous number of solutions Correlation error
Measurement of q13: Intrinsic degeneracy For neutrinos and antineutrinos of the same energy and baseline the system of equations has two intersections. The true one (q13,d) and a second, energy dependent point (clone) that introduces and ambiguity in the determination of the parameters Degeneracy error
Discrete degeneracies Two other sources of degeneracy. Ignorance of the sign of Dm232 Ignorance of the octant of q23 These two discrete values assume the value 1
How to solve degeneracies Use spectral information on oscillation signals experiment with energy resolution Combine experiments differing in E/L (and/or matter effects) need two experiments Include other flavor channels: silver channel nent. Need a tau-capable detector Burguet et al, Nucl.Phys.B608:301-318,2001
Precision on q23 ,Dm23 Improve one order of magnitude LBL measurements
The effect of correlation and degeneracies It spoils seriously the sensitivity to q13 Depends on d
Neutrino Factory ADR, Gavela, Hernández S. Geer
1 mm t n Pb Emulsion layers Detectors for NUFACT 10 x Minos 5 x Opera 10 x Icarus Migliozzi Cervera, Didak, JJGC Rubbia, Bueno, Campanelli
Golden & Silver channels at NUFACT ADR, Gavela, Hernández Donini, Migliozzi, Meloni
NUFACT Muon beams (NUFACT) pose a yet not fully solve technological challenge. However, the needed detectors are massive but straight-forward extrapolations of existing technology. All appearance and disappearance channels are available, thanks to high energy and the simultaneous production of two neutrino beams (however, very good charge separation is necessary). If sufficient luminosity is achieved one can reach ultimately sensitivity to q13, d and the neutrino mass hierarchy.
Super(Beta)-Beam The Super Beam/Beta-Beam offers and alternative/complement to the Neutrino Factory. Different technology, different systematic errors and different E/L. Combination of both facilities is ideal to solve degeneracies. Distances are short and matter effects are difficult to observe. Taus are not produced, thus no silver channel available. T2K-II/beta-beam will need for ultimate sensitivity 1Mton class detector. Such a detector has a great physics potential (proton decay, supernova observatory) of their own, but it is extraordinarily challenging to build (10-20 times the size of Super-Kamiokande).