Theoretical Status of Neutrino Physics M Lindner MaxPlanckInstitute
- Slides: 46
Theoretical Status of Neutrino Physics M. Lindner Max-Planck-Institute, Heidelberg WIN 07 - 21 st International Workshop on Weak Interactions and Neutrinos Saha Institute of Nuclear Physics, Kolkata, India January 15 -20, 2007 M. Lindner WIN 07, January 15 -20, 2007
New Physics Beyond the SM experimental facts: ~1016 Ge. V limits on p decay Dark Matter and Dark Energy baryon asymetry mn> 0 neutrino masses & mixings indirect tests of GUT scale physics precision in the flavour sector gauge bosons Higgs quarks leptons SUSY ~Te. V gauge hierarchy problem: dm. H 2 ~ L 2 flavour problem: 3 generations many parameters (mi , mixings) ~LGUT unification into GUTs mn=(m. D)TMR-1 m. D M. Lindner WIN 07, January 15 -20, 2007 astrophysics & cosmology +seesaw 2
Neutrino Mass Operators d=4 renormalizable mass operators natural scale symmetry n. L x SM with n. L only mn=0 introduce n. R = 1 L n. L g. N n. R x <f> = v n. R x n. R Majorana, /L seesaw mechanism (type I) mn=m. DMR-1 m. DT mh=MR For m 3 ~ (Dm 2 atm)1/2, m. D ~ leptons MR ~ 1011 - 1016 Ge. V è neutrinos are Majorana particles , mn probes ~ GUT scale physics! / symmetries of m. D , MR è smallness of neutrino masses high scale of L, M. Lindner WIN 07, January 15 -20, 2007 3
More Mass Operators ML =/ 0 n. L ~ <D>2 x n. L Seesaw type II mn=ML - m. DMR-1 m. DT x Further extensions: è SUSY è extra dimensions è … In general: • mass matrix for all neutrino-like fields • every term has a natural scale symmetries GUT, flavour symmetry, lepton number, . . . • diagonalization complicated dependence on all parameters M. Lindner WIN 07, January 15 -20, 2007 4
d=5 Neutrino Mass Operators M. Lindner WIN 07, January 15 -20, 2007 5
Parameters for 3 Light Neutrinos mass & mixing parameters: m 1 , Dm 221, |Dm 231| , sign(Dm 231) diag(eia, eib, 1) ne nm nt questions: Dirac or Majorana absolute mass scale: m 1 mass ordering: sgn(Dm 231) how small is q 13, q 23 maximal? leptonic CP violation L/E pattern of oscillations LSND sterile neutrino(s) M. Lindner WIN 07, January 15 -20, 2007 normal inverted hierarchical or degenerate 6
Kinematical Mass Determination KATRIN 0. 25 e. V ? Future: KATRIN M. Lindner c. f. comological bounds WIN 07, January 15 -20, 2007 7
Neutrino-less Double b-Decay < 0. 35 e. V ? n Heidelberg-Moscow experiment Majorana n 0 n 2 b decay | | free parameters: m 1 , sign(Dm 231) , CP-phases F 2, F 3 M. Lindner WIN 07, January 15 -20, 2007 8
New 0 n 2 b Experiments m 1 small mee =const. ~ (Dmij 2)1/2 m 1 large mee ~ m 1 sign(Dm 231) Claim of part of the original Heidelberg-Moscow experiment cosmology ‚tension‘ aims of new experiments: • test HM claim • (Dm 312)1/2 ~ 0. 05 e. V + errors reach 0. 01 e. V CUORE GERDA phases I, II, (III) • Cosmology: syst. errors X 10? • errors of 0 n 2 b nuclear matrix elements! • theory alternatives: LR, RPV-SUSY, . . . lepton number violation LHC, LFV, cosmology M. Lindner WIN 07, January 15 -20, 2007 9
Cosmology and Neutrino Mass • n‘s are hot dark matter smears structure formation on small scales • WMAP+2 d. FGRS + Lya mass bound: Smn< 0. 17. . . 1. 2 e. V implicit assumptions / conservative • 3 degenerate neutrinos, conservative approach mn < 0. 25 e. V future improvements: ~factor 5 -10 ? • comparison with 0 n 2 b, LSND M. Lindner WIN 07, January 15 -20, 2007 Tegmark fn=Wn/Wmatter 10
Status of Neutrino Oscillations solar: GALLEX/GNO SK, SNO Reactors: KAMLAND Beams: K 2 K, MINOS, OPERA atmospheric: Super. Kamiokande Dm 221 described = (8. 2+0. 3) *by 10 -5 e. V 2 2 q tan~ + 0. 05 two independent 12 = 0. 39 Dm 2312 x 2 = (2. 5+0. 6) *10 -3 e. V 2 oscillations tan 2 q 23 = 1. 0 + 0. 3 surprise: large mixings! sin 22 q 13 < 0. 16 Chooz M. Lindner LSND? Mini. Boo. NE WIN 07, January 15 -20, 2007 11
The Future of Oscillation Physics Dm 2 and qij regions improved oscillation experiments è controlled sources & detectors è long baseline experiments with neutrino beams è reactor experiments with identical near & far detector = x Majorana. CP-phases q 23 S 13 3 flavour effects CP phase d q 12 matter effects Aims: improved precision of the leading 2 x 2 oscillations detection of generic 3 -neutrino effects: q 13, CP violation precision neutrino physics M. Lindner WIN 07, January 15 -20, 2007 12
Future Precision with Reactor Experiments identical detectors many errors cancel - è Double Chooz è Daya Bay è Reno? Angra? Triple Chooz? 3 flavour effect no degeneracies no correlations no matter effects E=4 Me. V 2 km M. Lindner 4 km 40 km 80 km WIN 07, January 15 -20, 2007 13
Double Chooz and Triple Chooz FD only addition of ND sin 22 q 13 sensitivity 2 nd FD Chooz limit < 0. 20 Double Chooz < 0. 02 Triple Chooz ? < 0. 008 2008 M. Lindner WIN 07, January 15 -20, 2007 14
Future Precison with New Neutrino Beams • conventional beams, superbeams MINOS, CNGS, T 2 K, NOn. A, T 2 H, … • • b-beams pure ne and n-e beams from radioactive decays; g ~ 100 neutrino factories clean neutrino beams from decay of stored m’s correlations & degeneracies, matter effects M. Lindner WIN 07, January 15 -20, 2007 15
Next Gen. Improvement: Dm 231 and sin 2 q 23 MINOS Huber, ML, Rolinec, Schwetz, Winter M. Lindner WIN 07, January 15 -20, 2007 16
Sensitivity Versus Time b-beams neutrino factory proton driver? Range ~unknown CP phase combination with reactor synergies M. Lindner WIN 07, January 15 -20, 2007 17
Leptonic CP-Violation assume: sin 22 q 13= 0. 1 , d=p/2 combine T 2 K+NOn. A+reactor Dm 2 > 0 Dm 2 < 0 90%CL 3 s è bounds or measurements of leptonic CP-violation è leptonic CP-violation in MR baryon asymetry via leptogenesis M. Lindner WIN 07, January 15 -20, 2007 18
The Value of Future Precision Experiments Coming improvements: • MINOS: improved oscillation parameters • Mini. BOONE LSND • L/E dependence of oscillations • KATRIN • Better 0 n 2 b limits / signals • … But why do we need precision measurements? M. Lindner WIN 07, January 15 -20, 2007 19
Precision allows to learning about… • • solar neutrinos Sun atmospheric neutrinos primaries, x-sextions, … Geo neutrinos Earth reactor neutrinos nuclear physics neutrino beams accelerator physics supernova neutrinos element formation, … UHE neutrinos sources … • Flavour: è unique information è very precise: no hadronic uncertainties è different from quarks see-saw è tests models / ideas about flavour M. Lindner WIN 07, January 15 -20, 2007 20
Learning about Flavour History: Elimination of SMA Next: Smallness of q 13 • models for masses & mixings • input: known masses & mixings distribution of q 13 „predictions“ q 13 often close to experimental bounds What if sin 22 q 13 < 0. 01 ? Was favoured by almost all theorists GUTs preferred by nature M. Lindner èis q 13 small or tiny? similar: èis q 23 maximal or just large? numerical coincidence or symmetry answering questions precision WIN 07, January 15 -20, 2007 21
Further Implications of Precision allows to identify / exclude: • special angles: q 13= 0°, q 23= 45°, . . . discrete f. symmetries? • special relations: q 12+ q. C = 45° ? quark-lepton relation? • quantum corrections renormalization group evolution Provides also measurements or tests of: • MSW effect (coherent forward scattering and matter profiles) • cross sections • 3 neutrino unitarity sterile neutrinos with small mixings • neutrino decay (admixture…) • decoherence • NSI • MVN, . . . various synergies with LHC and LFV M. Lindner WIN 07, January 15 -20, 2007 22
Renormalization Group Running low energies: renormalization group running • small masses • large mixings atmospheric solar high energies: • mass models • flavour-symmetries • GUT-models, . . . bi-maximal q 23= p/4 + ? MSSM example: Antusch, Kersten, ML, Ratz Dq 13 versus limit/value reactor M. Lindner Small or even zero WIN 07, January 15 -20, 2007 23
Requirements: gauge unification particle multiplets n. R proton decay … Leptons Gauge unification suggests that some GUT exists Quarks The larger Picture: GUTs 1. 2. 3. generation many models… M. Lindner WIN 07, January 15 -20, 2007 24
GUT Expectations and Requirements Quarks and leptons sit in the same multiplets è one set of Yukawa couplings for given GUT multiplet è ~ tension: small quark mixings large leptonic mixings è this was in fact the reason for the `prediction’ of small mixing angles (SMA) – ruled out by data Mechanisms to post-dict large mixings: è sequential dominance è type II see-saw è Dirac screening è… M. Lindner WIN 07, January 15 -20, 2007 25
Single right-handed Dominance If one right-handed neutrino dominates, e. g. y >> x è small sub-determinant ~ m 2. m 3 è m 2 << m 3 i. e. a natural hierrachy è tan q 23 ~ a/c i. e. naturally large mixing M. Lindner WIN 07, January 15 -20, 2007 26
Sequential Dominance sequenatial dominance: z >> y >> x è small determinant ~ m 1. m 2. m 3 è m 1 << m 2 << m 3 natural è naturally large mixings M. Lindner WIN 07, January 15 -20, 2007 S. F. King 27
Large Mixings and See-Saw Type II see-saw type II: - rather natural - interference of two terms mn=ML - m. DMR-1 m. DT m. D and MR may posess small mixings and hierarchy However: ML can be numerically more important Example: Break GUT SU(2)L x SU(2)R x U(1)B-L ML from LR è large mixings natural for almost degenerate case m 1~m 2~m 3 è type I see-saw would only be a correction type I – type II interference W. Rodejohann, ML è ML ~ m. DMR-1 m. DT è many possibilities M. Lindner WIN 07, January 15 -20, 2007 28
Dirac Screening Question: Do neutrino masses always depend on the Dirac Yukawa couplings? no ML, Schmidt, Smirnov Assume: n. L, n. CR, S double seesaw fit fermions into GUT representations relation between Yukawa couplings, e. g. E 6 M. Lindner WIN 07, January 15 -20, 2007 29
Consequences of Dirac Screening complete screening of Dirac structure Outcome: • Neutrino masses can emerge completely from Planck scale physics generically different • Dirac Yukawa structure (small mixings) screened • Hierarchical neutrino spectrum not required in see-saw • Quark-lepton complimentarity possible … …with or without degenerate neutrino masses • Double see-saw predics for MR to be below MGUT first see-saw MR ~ <s>/MS ~ 10 -3 MGUT ~ 1013 Ge. V M. Lindner WIN 07, January 15 -20, 2007 30
Flavour Unification • so far no understanding of flavour, 3 generations • apparant regularities in quark and lepton parameters flavour symmetries (finite number for limited rank) symmetry not texture zeros Leptons Quarks Examples: 1. M. Lindner 2. 3. generation Nothing WIN 07, January 15 -20, 2007 31
Discrete Flavour Symmetries flavour structure Example: Dihedral groups Dn geometric origin of D 3 M. Lindner WIN 07, January 15 -20, 2007 32
Specific Example: D 5 complex generators Hagedorn, ML, Plentinger Kronecker products character table Clebsch-Gordan Coefficients … M. Lindner WIN 07, January 15 -20, 2007 33
D 5 Allowed Mass Terms Task: search for mass terms which are for suitable Higges singlets under D 5 Notation: ith generation fermions Dirac mass terms: Majorana mass terms: with M. Lindner WIN 07, January 15 -20, 2007 34
Resulting D 5 Symmetry Texture D 5 singlet mass terms require the following quantum numbers for the scalars: check phenomenology M. Lindner OK + “predictions” PROBLEM: To many sucessful possibilities WIN 07, January 15 -20, 2007 35
GUT 0 Flavour Unification t up-type quarks down-type quarks charged leptons neutrinos e d u s GUT group 0 flavour group example: SO(10) 0 SU(3)F c - SSB of SU(3)F between LGUT and LPlanck - all flavour Goldstone Bosons eaten - discrete sub-groups survive SSB e. g. Z 2, S 3, D 5, A 4 structures in flavour space compare with data b GUT 0 flavour is rather restricted small quark mixings *AND* large leptonic mixings ; quantum numbers è so far only a few viable models; e. g. SO(10) 0 S 4 Hagedorn, ML, Mohapatra è rather limited number of possibilities; phenomenological success non-trivial aim: distinguish models by future precision M. Lindner WIN 07, January 15 -20, 2007 36
The Interplay of Topics SM extensions: SUSY, … flavour symmetries unification fundamental interactions CPT & Lorentz inv. extra dimensions … leptogenesis supernovae BBN structure formation, UHE neutrinos dark matter & energy. . . precision neutrino properties: masses, mixings, CP-phases, . . . mass spectrum, mixings, CP-phases, lepton flavour violation, 0 n 2 b-decay, . . . n-parameters extremely valuable M. Lindner long term: most precise flavour info WIN 07, January 15 -20, 2007 37
Neutrinos as Unique Probes Astronomy: Supernovae GRBs UHE n‘s Sun Cosmology Reactors Atmosphere Accelerators Earth M. Lindner WIN 07, January 15 -20, 2007 38
Solar Neutrinos: Learning About the Sun Observables: - optical (total energy, surface dynamics, sun-spots, historical records, B, . . . ) - neutrinos (rates, spectrum, . . . ) Topics: - nuclear cross sections - solar dynamics - helio-seismology - variability - composition M. Lindner WIN 07, January 15 -20, 2007 39
Learning from Atmospheric Neutrinos primary cosmic-ray interaction in the atmosphere cascade of secondaries p, K decay of secondaries m nm ne Issues (in flux models): - primaries (. . . ) - atmosphere - cross sections - B-fields - shower models -. . . m nm ne nm nm neutrinos from decays of other particles M. Lindner WIN 07, January 15 -20, 2007 40
Supernova Neutrinos • Collaps of a typical star ~1057 n‘s • ~99% of the energy in n‘s • n‘s essential for explosion • 3 d simulations do not explode (so far. . . 2 d 3 d, convection? . . . ) Dighe, Smirnov MSW: SN & Earth sensitive to finite q 13 and sgn(Dm 2) M. Lindner WIN 07, January 15 -20, 2007 41
2 possibilities: Supernova neutron star Keeps cooling. . . or black hole abrupt end of n-emission • impressive signal of a black hole in neutrino light • neutrino masses edge of n-signal M. Lindner WIN 07, January 15 -20, 2007 42
Supernovae & Gravitational Waves gravitational wave emission quadrupol moment of the explosion Dimmelmeier, Font, Müller è additional information about galactic SN è global fits: optical + neutrinos + gravitational waves è neutrino properties + SN explosion dynamics è SN 1987 A: strongest constraints on large extra dimensions M. Lindner WIN 07, January 15 -20, 2007 43
Neutrinos & Te. V g´s HESS: Te. V g‘s HESS and EGRET: • Te. V g‘s from galactic center and galactic plane • 8 sources observed • some are at the position of known SN remnants • others do not correlate to anything known? Plausible explanation: -SN shock front acceleration - g´s from p 0 decay n flux from GC n signal @ km 3 detectors galacti c center M. Lindner p n p+ p 0 WIN 07, January 15 -20, 2007 HE g´s @ HESS, EGRET HE n´s 44
Neutrinos & Cosmology • Dark Matter ~ 25% • Dark Energy 70% • mass of all neutrinos: 0. 001 < Wn < 0. 02 • baryonic matter WB ~ 0. 04 >> visible matter neutrinos important for: è Big Bang nucleosynthesis (BBN) è structure formation ( mn) è connections to L? è leptogenesis alternatives (phase transition, AD, …DLG) include? See talk by E. Masso M. Lindner WIN 07, January 15 -20, 2007 45
Conclusions Neutrinos probe new physics in many ways! M. Lindner WIN 07, January 15 -20, 2007 46