Constraints for New Physics from Matter Effects on Neutrino Oscillation

1. Constraints for New Physicsfrom Matter Effectson Neutrino Oscillation Minako Honda (Ochanomizu Univ.) and Naotoshi Okamura (YITP) Yee Kao (Virginia Tech.) Alexey Pronin (Virginia Tech.) Tatsu Takeuchi (Virginia Tech.) based on hep-ph/0602115 hep-ph/0603268 hep-ph/0611xxx Joint Meeting of Pacific Region Particle Physics Communities (@Honolulu, Hawaii) 2006.10.31

2. n n p p e- e- Today’s Theme • Do interactions between neutrinos and matter due to “New Physics”have an effect on neutrino oscillations?? -beam 2. Can such effects be measured experimentally??&be used to constrain “New Physics”??

3. Introduction

4. In many models beyond the SM,the universality of the couplingscan be violated through radiative corrections. beam (a) charged current interaction processes ex) MSSM with etc... lead to the NC universalityviolation Universality Violation in NC Matter effect (b) neutral current interaction

5. Direct exchange of New Particles • New Physics that can contribute to neutrino oscillations: • Supersymmetric R-parity violating couplings • Z’ in Gauged B-(Le+L+L)with • Z’ in Topcolor assisted Technicolor • Leptoquarks that couple different generations • etc. E.Ma,PLB433,74(1988) C.T,Hill,PLB345,483(1995) etc.. W.Buchmuller et.al.PLB191,442(1987) e.g.)

6. Experimental constraintson universality violation in NC

7. invisible NO CONSTRAINT individual decay The experimental constraints ~invisible decay width~ LEP @ CERN LEP/ OPAL, DELPHI, L3, ALEPH, SLD No information is availableon the individual decay widths into each flavor

8. Z couplings to neutrinos cf ) Z couplings to charged leptons 0.9-1.2 PLB180,303(1986), PLB320,203(1994) LEP/ OPAL, DELPHI, L3, ALEPH, SLD LEP invisible decay width (total width is constrained.) The experimental constraints~individual~ CHARM, CHARM II @ CERN (’80s)

9. CHARM, CHARM II PLB180,303(1986), PLB320,203(1994) • The theoretical possibility of universality violation in many models • The weakness of the current experimental bounds It would be interesting to analyze the effect of such a violation on neutrino oscillations.

10. Plan of Talk • Introduction • Matter effect • effective potentials for neutrinos in matter W and Z exchange • effective mixing angles and oscillation probabilities When Neutral Current (NC) universality is violated • Can we see ? (A hypothetical experiment) Fermilab NuMI beam ⇒ Hyper-Kamiokande detector (1Mt) • Constraints on "New Physics” (e.g. leptoquarks,…) • Summary

11. Matter Effect • effective potentials • effective Hamiltonian

12. in ordinary matter The effective potentials(W & Z exchange) charged current interaction neutral current interaction

13. The effective Hamiltonian U:MNS matrix NC CC derived from universality violationin Neutral Current interaction central valueof CHARM : measure of universality violation in NC ： effective mixing matrix ： effective mass-squares

14. mixing angles • oscillation probabilities Using the “Jacobi method”, …

15. effective mixing angles(normal hierarchy) : violation factor in NC (details in our paper)

16. effective mixing angles(inverted hierarchy) : violation factor in NC (details in our paper)

17. Survival Probabilities ( )

18. @17GeV @17GeV 40% 40% oscillation dip The oscillation probabilities ( L=9,120km ) normal hierarchy inverted hierarchy atm</4 neutrino beam energy [ GeV ] neutrino beam energy [ GeV ]

19. The oscillation probabilities ( L=9,120km ) normal hierarchy inverted hierarchy neutrino beam energy [ GeV ] neutrino beam energy [ GeV ]

20. @17GeV @17GeV 40% 40% oscillation dip The oscillation probabilities ( L=9,120km ) normal hierarchy inverted hierarchy atm</4 neutrino beam energy [ GeV ] neutrino beam energy [ GeV ]

21. Can be measured experimentally ?one example“Fermilab– HyperK”

22. small value () large matter effect high energy (E~O(10)GeV) verylong base-line (L~O(10,000)km) to Japan from Japan(J-PARC) Fermilab-Japan

23. Main Injector @ Fermilab NuMI Beam no oscillation 17GeV Fermilab (NuMI) Hyper-Kamiokande[ L~9,120 km ] HK (1Mt) 9,120km ~732x12 MINOS @Soudan 732km We can expecta non-negligible event rate Fermilab

24. The expected number of events @ HK after 5 years of data taking (1Mton) 4000 3500 3000 2500 number of events 2000 17GeV 1500 oscillation dip 1000 We can expect the green lineto be clearly distinguishablefrom the blue or pink lines. 600 500 0 0 5 10 20 15 25 30 neutrino beam energy [ GeV ]

25. The constrains on universality violation  2 / 14dof (8GeV-22GeV) 100 10years much tighter constraintsthan that fromCHARM and CHARMII 5years 80 3years 60 1year 40 99%C.L. 95%C.L. 20 90%C.L. 0.025 -0.025 0 0.01 -0.03 -0.02 -0.01 0 0.02 0.03 ~0.005 ~0.015

26. Constraints on “New Physics” • Leptoquarks • Z’ Gauged B-(Le+L+L) with 

27. 1. Leptoquarks S : scalar, V : vector, subscripts : dim of SU(2) rep. W.Buchmuller et.al.PLB191,442(1987) Lower bounds on Leptoquark masses dependence 0.65

28. 2. Z’ Gauged B-(Le+L+L) with  E.Ma,PLB433,74(1988), etc.. dependence on Z’ mass Lower bounds on Z’ mass -0.005 0.005 5.5TeV

29. Lower limit on Gauged B-(Le+L+L), with  Fermilab to hyper-kamiokande experiment, • can lead to a “marked improvement”, • are comparable to the LHC result, and can be used as a “complimentary test”.

30. Summary We investigated the matter effect on neutrino oscillationfrom universality violation in neutral current interactions. This result is highly sensitive to the value of sin2(223) Fermilab Hyperkamiokande experiment If sin2(223) is as small as 0.92, the current 90% lowerbound, a 5-year measurement of survival spectrum could placea model independent constraint on NC universality violation at the 1% level.

31. A constraint on , can potentially place a strong constraint on possible “New Physics”. Leptoquarks Z’; Gauged B-(Le+L+L) with , etc… Fermilab HyperKamiokande experiment The indirect probe of these “new particles” can improve the existing bounds compete with the direct searches @LHC If these particles is discovered @LHC can serve as an “independent” and “complimentary” test of the LHC result.

32. Back Up Slides

33. charged current interaction neutral current interaction 2 Fierz tran. 2 : electron number density 0 : neutron number density The effective potentials

34. The energy dependence of the effective mass squared differences normal hierarchy inverted hierarchy [eV2] [eV2] neutrino beam energy [ GeV ] neutrino beam energy [ GeV ]

35. normal hierarchy inverted hierarchy [degree] [degree] neutrino beam energy [ GeV ] neutrino beam energy [ GeV ] The energy dependenceof the effective mixing angles (neutrino)

36. shift of effective mixing by  : violation factor in NC Sum up the calculation, (details in our paper) In the region of

37. depth (FNALHK) Matter Profile density (FNALHK) + average matter density

38. leptoquark many leptoquarks today, only S2 and V3, the others are in our paper

39. Z’ boson gauged B-(Le+L+L ) with (++ = 3) also, Topcolor Assisted Technicolor has Z’

40. SUSY R-parity violation ijk are already constrained »O(10-2), from lepton decays at tree level.