Antonio Palazzo

1. 1 NOW 2006 Conca Specchiulla, Otranto Neutrino mass and mixing: 2006 Status Antonio Palazzo University of Oxford and INFN, Bari based on work done in collaboration with: G.L. Fogli, E.Lisi, A. Marrone (Bari) A. Melchiorri, P. Serra (Rome) J. Silk , A. Slosar (Oxford)

2. 2 Outline •Introduction: The3 framework • Constraints on oscillation parameters •Constraints on absolute  masses •Combination of world ndata (when feasible) •Conclusions

3. 3 *Hint for a third DM2 ~O(eV2) from LSND: waiting for MiniBoone (dis)confirmation . Mass spectrum Norm. Hier. Inv. Hier. n3 n2 m2 - Absolute mass scale not probed by  oscillations n1 +Dm2 ? -Dm2 n2 - Hierarchy unknown m2 n1 n3 Mixing Sensitivities leading 2 S12~0.31 -Solar, KamLAND (dm2,q12,q13) 2 sub-leading S23~0.45 - ATM, K2K, MINOS (Dm2,q23,q13) 2 S13<few% - CHOOZ (Dm2,q13)

4. 4 Constraints on the leading “solar” parameters

5. 5 2nSolarconstraints Consistency among four different experiments LMA essentially determined by SNO + SK sensitive to high energy 8Bn’s

6. 6 LMA solution confirmed byKamLAND Disappearance Spectral distortions 0 2 4 6 8

7. 7 2nSolar + KamLANDcontraints Very high level of consistency KamLAND dominates dm2constraints q12range determined by solar data

8. 8 Matter effects with standard size confirmed V(x) = 2 GF Ne(x) V(x)aMSWV(x) (dm2,q12) marginalized

9. 9 Constraints on the leading “atmospheric” parameters (pre-MINOS)

10. 10 Super-Kamiokande Evidence for atmospheric nm->ntoscillations angle dependence in zenith distributions oscillatory pattern no osc. in highL/Eresolution analysis

11. 11 confirmed by K2K: The first LBL accelerator experiment K2K energy spectrum No oscillation Best fit Both nm disappearance and spectral distortion observed No oscillation (normalized to data) Number of events En(GeV)

12. 12 Constraints from the 2nanalysis Stringent constraints from SK Perfect agreement with K2K Dm2range determined with a 24% accuracy (2s) Contours at 1, 2, 3  (1 dof)

13. 13 Limits on13

14. 14 CHOOZ and the upper bound on q13 Non observation of ne disappearance exclusion plot in the (m2, 13) plane m2 scale set by SK+K2K+(MINOS) Upper limit onq13 Anti-correlation between 13 upper limit and m2

15. 15 3nCHOOZ + (SK + K2K) constraints Strong upper bound onq13 Leading parameters stable for unconstrained13 Mild anti-correlation betweenDm2and q13

16. 16 3nSolar + KamLAND constraints Solar and KamLAND preferq13 = 0 Leading parameters stable for unconstrained13 Upper limit onq13 dominated by solar data …

17. 17 Gallium-SNO : tension for q13 = 0 SNO and Gallium: 3n constraints (1s) perfect agreement for q13 = 0 spoiled for increasing q13 See also Goswami & Smirnov , Phys.Rev.D 72 053011 (2005) (hep-ph/0411359)

18. 18 Impact of MINOS

19. 19 MINOS first results: Corroborate SK and K2K 735 Km MINOSenergy spectrum (hep-ex/0607088)

20. 20 …and improve parameters’ determination POST - MINOS PRE - MINOS Dm2noticeable improvement from 24% to 15% (2s) q23still dominated by atmospheric (SK) q13upper bound slightly improved

21. 21 Overview of the global analysis constraints

22. 22 up-to-date numerical ±2 ranges

23. 23 Constraints on absolute  masses

24. 24  decay: mi  0 can affect the spectrum endpoint Observable: “effective electron neutrino mass” Current limits: (Mainz + Troitsk) upper bound m< 1.8eV (2s)

25. 25 n p W e- = e- W n p Q Neutrinoless double bdecay (02) : possible if mi  0 andn = n (Z, A)  (Z+2, A) + 2e- 22b 02b Observable: “effective Majorana mass” Majorana phases No signal in all experiments, except for the claim of Klapdor et al. (Heidelberg-Moscow) claim accepted, min the range[0.43-0.81] eV (2s)* claim rejected, m< 0.81eV * Theoretical input for nuclear matrix elements taken from Rodin et al. (2006).

26. 26 1 eV mn = 0 4 eV 7 eV Cosmology: mi  0 can affect LSS and CMB massive n’s suppress the formation of small scale structures Observable: sum of neutrino masses Current limits: depend on the dataset considered. Sensitivity up to S < 0.17eV (2s) Ma, 1996

27. 27 Results from the analysis of cosmological data Bounds obtained with seven different data sets 2slimit data set 1-WMAP2.3 eV 2-WMAP + SDSS 1.2 eV 3-WMAP + SDSS + SN + HST + BBN 0.78 eV 4-WMAP + LSS + SN0.75 eV 5-WMAP + LSS + SN + BAO 0.58 eV 6-WMAP + LSS + SN + Ly-a 0.21 eV 7-WMAP + LSS + SN + BAO + Ly-a 0.17 eV

28. 28 superposedconstraints on (mb, m, ) n oscillations - Significant correlations - Partial overlap ofNHand IH - Large m spread - Lower bound on S bdecay Irrelevant in all cases except when combined with the less stringent cosmo data set (1) Tension between Cosmology and 0n2b claim …

29. 29 combination of 0n2b claim with cosmological bounds not feasible most “aggressive” data set (7) we disregard most of the cosmological data and consider only the WMAP results … unless

30. 30 However, we should not be too hasty in concluding that : “cosmological data rule out the claim of Klapdor et al.,” since: - The 0n2bsignal might be due to new physics beyond light Majorana n’s - Astrophysical data may be still affected by unknown systematics - Bounds on S unavoidably depend on assumptions on the Cosmological Model Only an another 0n2b experiment with higher sensitivity can (dis)prove such claim

31. 31 Conclusions flavor oscillations - All the existing data* fit perfectly within a 3n framework - Basic parameters determined with a [10-30]% accuracy - Latest major improvement coming from MINOS (24%  15% on Dm2) absolute neutrino masses - Cosmology most sensitive probe at the moment providing sub-eV upper bounds - Tension with the Heidelberg-Moscowclaim requires further scrutiny in both fields - bdecay: promising (KATRIN) *Except for LSND