Hiroaki SUGIYAMA (Univ. of Toyama, Japan) 1/21

Transcription

1 Hiroaki SUGIYAMA (Univ. of Toyama, Japan) 1/21

2 Introduction 2/21 Neutrino masses are extremely smaller than other fermion masses. Naïve : Tree-level neutrino mass with SM Higgs VEV Particles : Interactions : No extension of scalar sector Dirac neutrino mass : Unnatural? Other mechanism? (Seesaw etc.) Generated at loop-level? Extended scalar sector S. Nasri and S. Moussa, MPLA17, 771 (2002) S. Kanemura, T. Nabeshima, HS, PLB703, 66 (2011)

3 Seesaw : Tree-level neutrino mass with SM Higgs VEV 3/21 Particles : No extension of scalar sector Interactions : Majorana neutrino mass : P. Minkowski, PLB67, 421 (1977) T. Yanagida, KEK-79-18, p.95 (1979) M. Gell-Mann, et al., in Supergravity (1979) Far from experimental reach Generated at loop-level? Extended scalar sector Why light? Low-scale cut-off? (Extra Dim., Strong Dynamics, etc.) S. Kanemura, T. Nabeshima, HS, PRD85, (2012)

4 New scalars which couple only with leptons ( leptophilic ) 4/21 Lepton Lepton New scalar : predictive Lepton New Fermion New scalar : free TeV scale Predictions Production & collider experiments Flavor structure of leptonic decay via the Yukawa Measurements Parameters unrelated to oscillation The lightest mass eigenvalue Oscillation data Majorana CP-violating phases Origin of neutrino mass Lepton flavor mixing structure

5 Yukawa Interactions with Leptophilic Scalars 5/21 singlet doublet : Singly charged : Doubly charged (e.g., in Zee model) (e.g., in Zee-Babu model) Loop-level Majorana mass with SM Higgs VEV : Neutrinophilic doublet triplet Dirac neutrinos Tree-level mass with new VEV (e,g., in Higgs Triplet Model) Majorana neutrinos

6 6/21 Doubly charged Singly charged Neutral singlet doublet ii ) iv ) iii ) triplet i ) iii )

7 7/21 Doubly Charged Scalar Doubly charged Singly charged Neutral singlet doublet ii ) iv ) iii ) triplet i ) iii )

8 Doubly Charged Higgs - Triplet - 8/21 Higgs Triplet Model (or HTM-like ones) W. Konetschny and W. Kumer, PLB70, 433 (1977) M. Magg and C. Wetterich, PLB94, 61 (1980) T.P. Cheng and L.F. Li, PRD22, 2860 (1980) J. Schechter and J.W.F. Valle, PRD22, 2227 (1980) Yukawa : Symmetric Majorana neutrino mass : Loop suppression? S. Kanemura, HS, PRD86, (2012)

9 Information on Non-Zero (the lightest neutrino mass) 9/21 Observation in shaded region Impossible with Possible with A.G. Akeroyd, M. Aoki, HS, PRD77, See also J. Garayoa, T. Schwetz, JHEP0803,009 M. Kadastki, M. Raidal, L. Rebane, PRD77,

10 Doubly Charged Scalar - Singlet - 10/21 Zee-Babu Model A. Zee, NPB264, 99 (1986) K.S. Babu, PLB203, 132 (1988) Yukawa : Symmetric Antisymmetric Majorana neutrino mass :

11 Prediction for neutrino mass matrix 11/21 or Prediction for leptonic decay Negligible contribution of to (assumption) K.S. Babu and C. Macesanu, PRD67, (2003) D. Aristizabal Sierra and M. Hirsch, JHEP0612, 052 (2006) M. Nebot et al., PRD77, (2008) Measurement : or?

12 12/21 Singly Charged Scalar Doubly charged Singly charged Neutral singlet doublet ii ) iv ) iii ) triplet i ) iii )

13 Singly Charged Higgs - Doublet or Triplet - 13/21 Neutrinophillic Doublet F. Wang. W. Wang, J.M. Jang, Europhys. Lett. 76, 388 (2006) S. Gabriel and S. Nandi, PLB655, 141 (2007) S.M. Davidson and H.E. Logan, PRD80, (2009) Yukawa : Only for neutrinos : odd Dirac neutrino mass : cf. Loop suppression? S. Kanemura, T. Matsui, SH, work in progress

14 14/21 S.M. Davidson and H.E. Logan, PRD80, (2009) Measurement :

15 The same for triplet 15/21 P. Fileviez Perez et al., PRD78, (2008)

16 Singly Charged Scalar - Singlet 1-16/21 The simplest Zee Model A. Zee, PLB93, 389 (1980) L. Wolfenstein, NPB175, 93 (1980) No Flavor-Changing-Neutral-Current Yukawa : Antisymmetric Majorana neutrino mass : Excluded by Oscillation data e.g., X.G. He, EPJC34, 371 (2004)

17 General (Original) Zee Model A. Zee, PLB93, 389 (1980) 17/21 Yukawa : Antisymmetric Incl. FCNC Majorana neutrino mass :

18 Prediction for neutrino mass matrix 18/21 Negligible contributions of and to (assumption) or Prediction (Majorana phase) Daya Bay : Measurement :? See also X.G. He, S.K. Majee, JHEP1203, 023 (2012)

19 Singly Charged Scalar - Singlet 2-19/21 Yukawa : Antisymmetric Majorana neutrino mass : Dirac neutrino mass : Example : Zee-Babu model Example : 1-loop model A. Zee, NPB264, 99 (1986) K.S. Babu, PLB203, 132 (1988) S. Nasri and S. Moussa, MPLA17, 771 (2002) S. Kanemura, T. Nabeshima, HS, PLB703, 66 (2011)

20 Prediction for neutrino mass matrix 20/21 or Prediction for leptonic decay Measurement : K.S. Babu and C. Macesanu, PRD67, (2003) D. Aristizabal Sierra and M. Hirsch, JHEP0612, 052 (2006) M. Nebot et al., PRD77, (2008) S. Kanemura, T. Nabeshima, HS, PLB703, 66 (2011)

21 Summary 21/21 TeV-scale new scalars which couple only with leptons (others?) Flavor structure of leptonic decay via the Yukawa Predictions Measurements Parameters unrelated to oscillation The lightest mass eigenvalue Oscillation data Majorana CP-violating phases Origin of neutrino mass? Different VEV? Tree? Loop? Dirac? Majorana? Flavored Higgs? Flavor structure of mass matrix (Flavor Symmetry)

22 backup 22/21

23 Summary of My Hope /21 triplet : Doubly charged : or not or not or not Singly charged : or or not doublet :

24 Summary of My Hope /21 singly charged singlet : (Majorana) or (Dirac) doubly charged singlet : Zee-Babu model??

25 in the HTM 25/21 A.G. Akeroyd, S. Moretti, PRD86, (2012)

26 in the THDMs 26/21 P.M. Ferreira, R. Santos, M. Sher, J.P. Silva, PRD85, (2012)