``Before and After'' the End of Era of the Neutrino Anomalies? What Is Left? Standard and Non-Standard
A. Yu. Smirnov AS ICTP, Trieste, Italy
``Before and After’’ The end of era of the neutrino anomalies? What is left? Standard and Non-standard ``Neutrino Physics after KamLAND’’ started much before announcement of the first results Since 1998 -1999 most of the papers - in context of the LMA solution (phenomenology, implications etc..) Strong evidence of oscillations 1998 is the turn point of the atmospheric neutrinos ``Revolution 98’’: SMA MSW solution of the solar neutrino problem - disfavored
TheThe prejudice prejudice of of small small mixing mixing was was destroyed destroyed A Yu Smirnov Culmination of ~ 40 years of solar neutrino studies
has confirmed the LMA MSW solution excluded other solutions at least as dominant mechanisms
further shifted the allowed region and best fit point to larger ∆m2 (5 7) 10-5 eV2
The lower bound: ∆m2 > (4 - 5) 10-5 eV2 looks rather solid
Mixing is practically unaffected
Confirmation of the whole oscillation picture including oscillations of the atmospheric neutrinos
A Yu Smirnov Driving force of developments in the field
Real Fake: confirmed ITEP mass resolved 17 kev neutrino BUGEY oscillations KARMEN anomaly Troitzk anomaly ...
Related to neutrinos? UHE Cosmic Rays nucleosynthesis r-processes pulsar kicks
A Yu Smirnov Accepting the first KamLAND result CPT All other possibilities are excluded as leading effects
Still the allowed region should be diminished to identify physical processes:
High ∆m2 Averaged vacuum oscillations with small matter corrections Low ∆m2 Non-oscillatory adiabatic conversion (for E > 5 MeV)
Small mixing: Resonance description is valid Maximal mixing: ``Resonance’’ is at zero density
A Yu Smirnov s13 = 0.2
2ν -fit 3ν -fit
P.de Holanda, A.S., hep-ph/0212270 A Yu Smirnov P.de Holanda, A.S. hep-ph/0212270
AND % Identification of the unique region:
2ν analysis, sub-leading effects (13 -mixing) can be neglected
Precision measurements:
Possible sub-leading effects should be included. Generic 3ν analysis CC should be performed. NC Problem of degeneracy of parameters appears Lines of constant CC/NC ratio and Day-Night asymmetry at SNO A Yu Smirnov Over determine solution, cross checks in the b.f. point
Day -Night Asymmetries: AND(SNO) = 2 - 5 % , ADN(SK) = 2 - 3 %
Spectrum distortion: Turn up at low energies: 5 - 10 % Rate at the intermediate energies R = (0.6 - 0.7)R BOREXINO/KamLAND SSM
Seasonal variations Small (unobservable) effect: AWS < 0.5% Low energy experiments
- further confirmation of LMA - precise determination of the neutrino parameters - searches for physics ``beyond the LMA’’
A Yu Smirnov Pull-off diagrams for the best fit points of the l- and h- LMA regions
(2 - 2.5) σ pull
Statistical fluctuation ? Systematics? Related to time variations of rate? Neutrino properties: conversion driven by second ∆m2
Additional deep in the suppression pit at E ~ 1 MeV? QAr(LMA) > QAr(Homestake)
A Yu Smirnov Parameters from the 2ν analysis: The equality ∆m2 ∆m2 is satisfied tan2θ tan2θ within 1σ Solar KamLAND neutrinos Gives hint that CPT is OK Possible deviations (mismatch of parameters CPT-violation if the fit is done in terms of 2ν mixing): Physics Beyond the LMA
If some effect influences Some effect can influence KamLAND signal Inverse is solar neutrinos it should also show up not correct: but not KamLAND result in the solar neutrinos
A Yu Smirnov ∆m2 −θ region of sensitivity is much larger for solar neutrinos than for KamLAND Additional small ∆m2 or/and θ can strongly influence the solar neutrinos but not KamLAND
Magnetic moment: the Earth magnetic field is too small
Non-standard interactions (NSI) of neutrinos do not change the KL signal since the matter effect is small
Even in the CPT conserving case one can find
∆m2 , θ= ∆m2 , θ solar KL
A Yu Smirnov Adiabatic conversion (MSW) Vacuum oscillations
Matter effect dominates Matter effect is very small (at least in the HE part)
Non-oscillatory transition Oscillation phase is crucial the oscillation phase for observed effect is irrelevant
Adiabatic conversion Vacuum oscillation formula formula ∆m2 , θ
Coincidence of these parameters determined from the solar neutrino data and from KamLAND results testifies for the correctness of the theory (phase of oscillations, matter potential, etc..) See also F.L. Fogli et al., hep-ph/0211414 Physics of sub-leading effects
Magnetic moment, Searches for νe flux Time variations magnetic fields Beyond single ∆m2 inside the Sun context CC/NC Additional distortion of spectrum Additional contribution (non-standard to the matter effect neutrino interaction)
(violation of equivalence principle)
A Yu Smirnov Single ∆m2 context νe −> 1 − η νa + η νs P. de Holanda, A.S. hep-ph/0211264
3σ
2σ
1σ
η
The 3σ allowed region for The allowed region in the η − fB η = 0.0, 0.2, 0.4, 0.6 (from right to left) (boron neutrino flux) plane for different confidence levels A Yu Smirnov (KamLAND data simulation for 3years, 600 t)
The 1σ, 2σ, 3σ allowed regions from The dependence of the χ2 on η from the analysis of 3 years simulated a combined analysis of the solar data KamLAND data and simulated KamLAND results A Yu Smirnov Spin-flavor precession (resonance, non-resonance)
``Post-KamLAND’’ study E. Akhmedov, J. Pulido 2 2 in the context of single ∆m = ∆m LMA hep-ph/0209192
The effect (neutrino spin flip) is in the central regions B > 10 MG of the Sun (radiative zone)
Signature: Appearance of the antineutrino νe flux µ 22 F( νe) ν B (for the boron neutrinos) = 1.5% 10−12 µ F( νe) B 100 MG At the present SK bound (unless Voloshin’s Magnetic moment: µ ~ e m ν 2 ν cancellation, or polarization (natural* value) Λ suppression occurs)
−16 For the cut energy Λ = 100 GeV and mν = 1 eV: µν ~ 10 µB unobservable?
2 2 2 Beyond single ∆m : if for second ∆m << ∆m LMA effect can be much larger Back to the original task: J.N.Bahcall G.T.Zatsepin V.A. Kuzmin Diagnostics of the Sun
Determination of the original solar neutrino fluxes In a sense these fluxes do not exist since neutrino conversion starts already in the neutrino production region Still we can introduce these fluxes since there is no back influence of neutrino conversion on the solar characteristics and production of neutrinos. Conversion effects can be subtracted
J. N. Bahcall, M. Gonzalez-Garcia Determine neutrino fluxes from pp- and CNO - cycles C. Pena-Garay astro-ph/0212331 Searches for time variations of fluxes
A Yu Smirnov is the dominant mechanism of Very compelling evidence that ν <−> ν µ τ the atmospheric neutrino conversion vacuum oscillations - SuperKamiokande -K2K -MACRO - SOUDAN KamLAND gives an additional confirmation of the oscillation picture - confirms oscillations - large/maximal mixing in the lepton sector Nothing statistically significant beyond this picture
νe oscillations sterile neutrinos CP-violation CPT-violation
Searches for specific oscillation effects CR physics with atmospheric nu Oscillations of electron (anti) neutrino must
appear at some level even for θ13 = 0 due to the solar oscillation parameters Excess of the e-like events in certain energy range with - specific energy and - zenith angle dependence
Due to solar Due to non-zero θ13 2 2 ∆m 12, θ12 and atmospheric ∆m 13
Multi-GeV Sub-GeV events Interference events Excess of the e-like events in the sub-GeV
0 Fe = Fe (Pee + r Pµe)
Fe 2 0 - 1 = P2 ( r c23 -1) Fe
``screening factor’’ 2 P2 = P(∆m 12 , θ12) is the 2ν transition probability In the sub-GeV sample 0 0 r = Fµ / Fe ~ 2 The excess is zero for maximal 23- mixing Zenith angle dependence of the e-like events 0.Peres, A.S., hep-ph/0201069 F ε = e - 1 0 Fe
In the best fit points of the l- and h- LMA regions
2 sin 2θ23 εl , % ε h, % Excess increases 0.91 2.8 4.8 with ∆m2 0.96 1.9 3.2 0.99 0.9 1.6
Once the LMA parameters are known: restrict deviation of 23-mixing from maximal by measuring ε
A Yu Smirnov CHOOZ Excess of the e-like events in multi-GeV region
U - D A U/D = 2 A , % U + D U/D 5.0 5.8 6.7 U: cos Θ = (-1 -- -0.6) 7.5 Z 8.3 8.8 D: cos ΘZ = (0.6 -- 1)
Contours of constant up - down s 2 = 0.5 asymmetry of the e -like events 23
Akhmedov, A. Dighe, P. Lipari, A.S. A Yu Smirnov Zenith angle dependence Excess of the e-like events in the sub-GeV of the e-like events
Fe 2 0 - 1 = P2 ( r c23 -1) Fe -r s13 sin2θ23 Re (A*ee Aeµ)
2 2 -s13 [2(1 - r s 23 ) + P2 (r - 2)]
2 P2 = |Aeµ| is the 2ν transition probability
Interference term:
- linear in s13 - no screening effect - has opposite sign for neutrinos and antineutrinos 2 -5 2 - maximal if ∆m 12 = 7 10 eV 2 -5 2 ∆m 12 = 5 10 eV Can be dominant if 23-mixing is maximal: s εint ∼ 5% 13 0.3 (in maximum) 0.Peres, A.S., hep-ph/0201069 H. Nunokawa, O.L.G.Peres, R. Zukanovich Funchal, hep-ph/0302039
2 2 2 Fourth neutrino with ∆m ~ ∆m LSND ~ 0.5 eV resonance in the 0.5 - 1.5 TeV range For (3+1) scheme resonances are in νe −νs , νµ/τ −νs channels IceCube
(3) (3+1)
(3 +1) (3)
Upward-going muons Cascade events (induced by the CC Searches new neutrino states interactions of electron, and tau neutrinos Observation of the parametric effects and by the NC scattering) Ultimate oscillation anomaly?
A Yu Smirnov ν ν e s ν νµ τ
ν4 Generic possibility of interest even independently of the LSND result
Generation of large mixing of 2 ∆m LSND active neutrinos due to small mass mixing with sterile state
ν 2 3 ∆m atm ν Produces uncertainty in interpretation 2 ∆m2 ν1 sun of results Non-oscillation interpretation K. S. Babu, and S. Pakvasa, hep-ph/0204226 + + µ −−> e νe νi (e, µ, τ )
Due to exchange of new neutral scalar bosons with M = 300 - 500 GeV
|∆ L| = 2 key to avoid bounds from µ −−> eee , etc. Michel parameter ρ = 0 LSND and KARMEN better consistency ??
No effect for No effect for ``decay in flight’’ pion decay can not explain LSND data for neutrinos MiniBOONE can not check even if it will work both in neutrino and antineutrino modes
Observable e+ e- --> µ+ µ- effects in e+ e- --> νν γ Z0 --> e+ µ- νν with Br = 10-7
A Yu Smirnov Atmospheric antineutrinos: ~10 - 15% G. Barenboim et al, hep-ph/0212116 averaged oscillation effect After KamLAND: ultimate possibility? SuperK analysis of CPT excludes such ν ν a possibility?
Strong oscillation effect for νe driven by KamLAND oscillation parameters e τ µ ~8% excess of the e-like events in the sub-GeV region e τ µ MINOS: checks of oscillations in the neutrino and antineutrino channels
KamLAND can not check LMA. However… LOW, VO, SFP, etc., are not excluded yet, further check by SNO, BOREXINO… are needed
Mass spectra of neutrinos and antineutrinos MiniBOONE: null result in the neutrino mode In original scenario KamLAND positive result in the antineutrino mode would see very small oscillation effect G. Barenboim et al., JHEP 0210, 001 (2002) ``After KamLAND’’ In 1987 (SN 1987A) the effect of we can definitely say that the (anti)neutrino conversion had been observed. - conversion inside the star - oscillation in the matter of the Earth - the Earth matter effect was different for different detectors
With future SN bursts sin θ13 one can test type of mass hierarchy existence of new (sterile) neutrinos
Conversion of Original Observations Problem: neutrinos fluxes
Strong even for all neutrino Uncertainties very small mixing species are produced, of detection uncertainties substantially diminishes observable effect A Yu Smirnov Two well separated Comparison of signals Beam uncertainties detectors are used from the two detectors: can be controlled if Properties of medium oscillation effects between are know them and also test properties of the original flux
D1 D2 This is realized for oscillations of SN neutrinos inside the Earth: Fluxes arriving at the surface of the earth are the same for L1 both detectors ν L2 2 -4 If sin θ13 >10 an appearance of the Earth matter effect in ν or ( ν ) signal will testify ν e e for normal (inverted) mass hierarchy of neutrinos Talk by C. Lunardini R.C. Schirato, G.M. Fuller, astro-ph/0205390 The shock wave can reach the region relevant for the neutrino conversion ρ ~ 104 g/cc During 3 - 5 s from the beginning of the burst
Influences neutrino conversion if 2 -5 sin θ13 > 10 The effects are in the neutrino (antineutrino) for normal (inverted) hierarchy: h - resonance change the number of events R.C. Schirato, G.M. Fuller, astro-ph/0205390 ``wave of softening of spectrum’’ K. Takahashi et al, astro-ph/0212195 delayed Earth matter effect Density profile with shock wave propagation C.Lunardini, A.S., hep-ph/0302033 at various times post-bounce G. Fuller Studying effects of the shock wave on the properties of neutrino burst one can get (in principle) information on
time of propagation velocity of propagation shock wave revival time density gradient in the front size of the front
Can shed some light on mechanism of explosion Three neutrinos New neutrino states Sterile neutrinos
Massive, m ~< 1 eV New interactions Large anomalous Bi-large or dipole moments Large-maximal mixing
Smallness of neutrino mass is related to Effects of violation of Majorana nature Lorentz invariance Oscillations and matter CPT, conversion -- Equivalence principle common phenomena ...
A Yu Smirnov νe ν ν 2 µ τ |Ue3|
ν3 ν2 2 ∆m sun ν1
2 2 mass ∆m ∆m atm atm mass 2 |Ue3| ν2 ν1 ν3 2 ∆m sun Normal mass hierarchy Inverted mass hierarchy (ordering) (ordering)
Type of mass spectrum: with Hierarchy, Ordering, Degeneracy absolute mass scale Type of the mass hierarchy: Normal, Inverted
Ue3 = ?
A Yu Smirnov sinθ13 = |Ue3|
Type of mass hierarchy Normal or ordering: 2 Inverted sign ∆m 32 hierarchical Absolute scale of Type of mass spectrum partially degenerate neutrino mass m 1 quasi-degenerate
Dirac CP-violating phase, δ Leptonic Unitarity triangle
Nature of neutrinos: Dirac Majorana Majorana CP-violating phases, ρ, σ
2 ∆ m 21 Precision measurements 2 tan θ12 of oscillation parameters 2 Deviation from ∆m 32 2 maximal mixing sin 2θ23
A Yu Smirnov ty ri o ri p t es h g hi e th
Post -KamLAND, selecting LMA has confirmed strong dependence of the With ββ0ν searches it is not possible to fail effective Majorana mass on from scientific point of view CP-violation phases, any result - positive or improvement of bound possibility of cancellation of is of great importance contributions Can not become irrelevant after further developments A Yu Smirnov The main developments in neutrino physics where related to various ``neutrino anomalies’’ (both real and fake). The anomalies were driving force of both theoretical and experimental developments
Are solar and atmospheric neutrino problems solved? After KamLAND: What is left? LSND? New anomalies?
Does the ``standard picture’’ of neutrino mass and mixing emerge? Do neutrinos change their character becoming more predictable?
A Yu Smirnov Well defined program New perspectives: Lead to something characterized by - new neutrino states unexpected - further tests - new interactions -NuTeV - precision measurements - CPT-violation -Z0 - width - searches for /bounds on - ??? - ??? new physics
A Yu Smirnov Warning: Future High Energy experiments (LHC ...) may have serious impact Well defined program: on this program 1). Determination of masses, mixings, ``Technological problems’’ CP- phases absolute scale of neutrino Precision measurement of parameters mass, CP-phases - big challenge
2). Searches for new physics beyond Non-standard interactions ``standard picture’’ New neutrino states restrictions of exotics Effects of violation of -CPT - Lorenz invariance - Equivalence principle - Pauli principle 3). Identification of origins of Reconstruction of neutrino neutrino mass and mixing mass matrix tests of the see-saw (and other) mechanism - flavor violation processes - leptogenesis - high energy experiments A Yu Smirnov Of our knowledge of neutrino mass and mixing Geophysics Astrophysics Cosmology
A Yu Smirnov