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Cristina VOLPE (Institut de Physique Nucléaire Orsay, France)

Search for CP violation in the lepton sector. n. Cristina VOLPE (Institut de Physique Nucléaire Orsay, France). CP violation searches with future facilities. CP violation searches and astrophysics. Introduction. Conclusions. OUTLINE. Major advances in neutrino physics. L. SOURCE.

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Cristina VOLPE (Institut de Physique Nucléaire Orsay, France)

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  1. Search for CP violation in the lepton sector n Cristina VOLPE (Institut de Physique Nucléaire Orsay, France)

  2. CP violation searches with future facilities CP violation searches and astrophysics Introduction Conclusions OUTLINE

  3. Major advances in neutrino physics L SOURCE DETECTOR nm nm Pontecorvo, 1957 ne ne AN IMPRESSIVE PROGRESS IN THE LAST DECADE in our knowledge of its properties. oscillation decoherence decay 1.6 1.4 1.2 1 0.8 0.6 0.4 0.2 data/expectation Many puzzles have been solved with an incredible impact on various domains of physics. 1 10 102 103 104 Ln/En ratio [km/GeV]

  4. The solar neutrino deficit problem is clarified. Neutrinos are massive particles, contrary to what was believed for decades. It opens a new possibility to understand the matter versus anti-matter asymmetry in the Universe. Among the fundamental implications… The origin of neutrino mass and its smallness needs to be understood. We understand the energy production in stars. A key step for one of the major open questions in modern cosmology.

  5. THE 3-flavours OSCILLATION PARAMETERS Dm322 Dm212 Only two Dm2 are independent. q23 q12 q13 In the case of three families, there are three mass eigenstates (n1,n2,n3) and three flavour eigenstates (ne,nm,nt). n3 nm nt q23 The two basis are related by a unitary matrix, called the Maki-Nakagawa-Sakata- Pontecorvo (MNSP) matrix. n2 ne n1 q12 q13 ne n1 nm n2 nt n3 THE CP violating phase INTRODUCES A n-nASYMMETRY.

  6. THE key OPEN QUESTIONS > The third mixing angleq13 Double-CHOOZ, Daya-Bay, T2K,.. >The Dirac phase from double-beta decay experiments > TheMajorana phases > Theabsolute mass scale KATRIN, MARE,… >The mass hierarchy supernovae, n-factories, double-beta,… > Theneutrino nature Gerda, Cuore, Super-Nemo,… A wealth of experiments are under construction or at a R&D level. exciting discoveries might be close…

  7. q13– expected sensitivities P. Huber, M. Lindner, T. Schwetz, W. Winter, arXiv: 0907.1861 Discovery potential (90% CL) for sin22q13 from reactors and accelerators THE VALUE OF Q13 CRUCIAL FOR FUTURE STRATEGIES.

  8. CPV sensitivity P. Huber, M. Lindner, T. Schwetz, W. Winter, arXiv: 0907.1861 sensitivity limits (90% CL) from T2K, NOnA and reactors LONG-TERM expensive PROJECTS might be necessary.

  9. Long-term accelerator projects > Super-beams - intense conventional beams from muon and pion decay > Beta-beams – intense and pure neutrino beams from boosted accelerated ions > Neutrino factories– intense neutrino beams from stored muons THE GOAL : to investigate very small Q13 values, the Dirac CP phase and the mass hierarchy.

  10. 6He 6Li 6He 6Li ions are boosted ne ne The beta -beamconcept ions at rest neutrino beams Zucchelli, PLB 2002 Average neutrino energy : En = 2gQb, Flux emittance : 1/g. No beam associated background (the n-beams are produced from primary particles).

  11. Several beta-beam scenarios proposed Low-energy g= 5 -14 C. Volpe, Journ. Phys. G. 30 (2004), hep-ph/0303222. CP Electron-capture J. Bernabeu, J. Burguet-Castell, C. Espinoza, M. Lindroos, JHEP 0512 (2005) 014, hep-ph/0505054. See Volpe, Topical Review on “Beta-beams”, J.Phys.G34, R1 (2007) hep-ph/0605033 Beta-beams g= 100 P. Zucchelli, Phys. Lett. B 2002 High-energy g= 300 and very high-energy g= 1000 J. Burguet-Castell, D. Casper, JJ Gomez-Cadenas, P. Hernandez, F. Sanchez, Nucl. Phys. B695, 217 (2004), hep-ph/0312068.

  12. THE standard baseline scenario To a far detector SPS ne PS P. Zucchelli, Phys. Lett. B (2002) EURISOL B. Autin et al. , J. Phys. G 29 (2003) 1785. Proton driver SPL ISOL production ISOL target & ion source 6He,18Ne n source decay ring beam preparation ECR pulsed Lss = 2.5 km 93 GeV Ion acceleration Linac, 0.4 GeV acceleration at medium energy RCS, 1.5 GeV 8.7 GeV Acceleration to final energy PS and SPS ITREQUIRESTHE PRODUCTION AND ACCELERATION OF VERYINTENSE RADIOACTIVE IONS BEAMS (RIB). EURISOL Design Study (FP6 2005-2009) -> Conceptual Report

  13. THE standard baseline scenario 65 m ne MEGATON DETECTOR 60 m Frejus Underground Laboratory CERN 130 km FREJUS THE SEARCH for CP and T violation: MULTIPURPOSE DETECTOR CP violation, (relic) supernova neutrinos and proton decay. e m (+) m e (p+) e m (-) m e (p-) CP T Three technologies understudy (water Cherenkov, scintillator, liquid argon) LAGUNA Design Study (2008-10) (with Beta-beams) (conventional beams)

  14. IN THE LITERATURE… • Two kinds of studies of the physics reach can be found : • 1) based on values of the ion intensities and boosts that • are obtained extrapolating well-known technologies and • existing accelerators. • based on values of the ion intensities and boosts that are • treated as “free” parameters, with the aim of exploring • the conditions to achieve optimal sensitivities.

  15. Sensitivity to Q13 and CP violation Mezzetto 2005 After 10 years running (5+5, or 2+8) with 440 kton detector, 5.8 (2.2) 10 18 6He (18Ne)/s, g = 100 Campagne, Maltoni, Mezzetto, Schwetz, JHEP 0704:003 (2007). hep-ph/0603172

  16. Synergy with athmospherics First proposed in : . Hubert, Maltoni, Schwetz, Phys. Rev. D 71, 053006 (2005). hep-ph/0501037. Campagne, Maltoni, Mezzetto, Schwetz, JHEP 0704:003 (2007). hep-ph/0603172 Helps identify the mass hierarchy and the octant degeneracy.

  17. 1 0.6 Fraction of d b-beam 0.2 1 ISS study sin22q13 10-5 10-4 10-3 Comparison with other facilities International Scoping Study Physics Working Group, arXiv: 0710.4947 . THE BETA-BEAM PROJECT IS A COMPETITIVE option.

  18. LOW ENERGY BETA-BEAMS C.Volpe, J Phys G30 (2004). A proposal to establish a facility for the production of intense and pure lowenergy neutrino beams (100 MeV). BASELINE PHYSICS POTENTIAL n E U R I S O L n-nucleus cross sections (detector’s response, r-process, 2b-decay) SPS storage ring PS fundamental interactions studies (Weinberg angle, CVC test, mn) close detector n astrophysical applications PHYSICS STUDIED WITHIN THE EURISOL DS (FP6, 2005-2009)

  19. EURISOL DS(2005-09): Some conclusions Two sets of candidate ions are being considered : 6He/18Ne and 8B/8Li • Three ion production techniques have been and will be investigated. • the standard ISOL technique : • the requires 6He intensity is achievable, the 18Ne intensity lower • - direct production (M.Loislet-Leuven, M. Hass-Soreq, GANIL) : • 6He and 18Ne intensities should be achievable • - storage ring production : suitable for 8B/8Li. • The direct and storage ring production methods will be studied within EUROnu. C. Rubbia et al, NIM A 568(2006) 475. If the ions are bunched to suppress the backgrounds, there might be a conflict with the EURISOL requirements. The ion stacking method in the storage ring ok. IMPORTANT PROGRESS ON THE FEASIBILITY PERFORMED. Further work will be done within EUROnu both on the feasibility and on the physics reach.

  20. CP violation searches and astrophysics Solar neutrinos H.Minakata and S. Watanabe, Phys. Lett. B 468, 256 (1999). UHE neutrinos Walter Winter, Phys. Rev. D 74, 033015 (2006). Supernova neutrinos E. Akhmedov, C.Lunardini & A.Smirnov, Nucl.Phys.B643 (2002) 339. A. B. Balantekin, J. Gava, C. Volpe, PLB662, 396 (2008), arXiv:0710.3112. J. Gava, C. Volpe, Phys. Rev. D78, 083007(2008), arXiv:0807.3418. J Kneller and G.C. McLaughlin, arXiv:0904.3823.

  21. nt ne nm Core-collapse supernovae (SN) 99 % of the energy is emitted as neutrinos of all flavours in a short burst of about 10 s. NS A possible site for the nucleosynthesis of the heavy elements, but present calculations fail to reproduce the observed abundances. n-PROPERTIES CAN HAVE EFFECTS IN THE STAR OR IMPACT THE SIGNAL IN A SN OBSERVATORY.

  22. ne e W e ne V(r) GF re. There are also shock wave effects. These engender multiple resonances and phase effects. Neutrino propagation in media A NEW UNDERSTANDING OF n-PROPAGATION IN SN : The Mikheev-Smirnov-Wolfenstein (MSW) effect (’78, ’86) : neutrino coupling with matter induces a resonant flavour conversion. the beautiful explanation of the « solar neutrino deficit » problem ! Neutrino-neutrino interaction is important. A more complex problem : the neutrino evolution equations are non-linear. t=1s t=1.5s Turbulence effects are just being considered. E=20 MeV See the review from Duan and Kneller, arXiv:0904.0974 IMPRESSIVE PROGRESS IN THE LAST FEW YEARS ! A lot of work still needs to be done …

  23. The search for the third n-mixing angle First calculation including the n-n interaction and shock wave effects. FLUXES ON EARTH adiabatic Gava, Kneller, Volpe, McLaughlin, Phys. Rev. Lett. 103 (2009), arXiv:0902.0317 ne+ p n + e+ non-adiabatic 29 MeV 15 MeV POSITRON TIME SIGNAL The dip (bump) can be seen at 3.5 (1) sigma in Super-Kamiokande if a supernova at 10 kpc explodes.. A SIGNATURE IN THE POSITRON TIME SIGNAL IFsin22q13 > 10-5 OR sin2q13 < 10-5

  24. CP violation and core-collapse SN A. B. Balantekin, J. Gava, C. Volpe, PLB662, 396 (2008), arXiv:0710.3112 We have demonstrated under which conditions there can be CP violating effects in supernovae. Here the main steps : The neutrino evolution equations in matter are matterterm vacuum term with the T23 basis factorizes out easily and gives:

  25. CP violation and core-collapse SN Evolution operator in the T23 basis This leads to the two following relations: The electron neutrino survival probability does not depend on d. Exact relations, valid for anydensity profile. We have demonstrated that these relations also hold when the n-n interaction is included. J. Gava, C. Volpe, Phys. Rev. D78, 083007(2008), arXiv:0807.3418.

  26. Tree level NS Ln- neutrino fluxes at the neutrinosphere (Fermi-Dirac or power law ) 20 Km The neutrinosphere is where neutrinos finally decouple from matter. The electron neutrino flux in the SN: AT TREE LEVEL THE ne-FLUXES DO NOT DEPEND ON THE CP PHASE.

  27. Conditions for CP effects in SN Beyond the Standard Model might introducedifferences in the nm and nt interaction wihtmatter (Flavor ChangingNeutralCurrents, …). In the Standard Model loop corrections for the v interaction with matter should be included. at the neutrinosphere AND also The n propagation Hamiltonian does not factorize any more ! THERE CAN BE CP-VIOLATION EFFECTS IN SUPERNOVAE.

  28. Numerical results : effects on the flux ratios Standard MSW, tree level 200 Km in the star More realistic case ! n-n interaction and 1-loop fe (d = 180°)/ fe (d = 0°) Inverted hierarchy and small J. Gava, C. Volpe, Phys. Rev. D78, 083007(2008), arXiv:0807.3418. EFFECTS OF 5-10 % ON THE ELECTRON NEUTRINO FLUXES in the SUPERNOVA.

  29. Numerical results : effects on Ye The electron fraction is a key parameter for the r-process nucleosynthesis : Ye (d = 180°)/Ye (d = 0°) A. B. Balantekin, J. Gava, C. Volpe, PLB662, 396 (2008), arXiv:0710.3112 VERY SMALL EFFECTS ON THE ELECTRON FRACTION.

  30. The value of Q13 sets the strategy for CP violation searches. • Beta-beams • - A very competitive option. • The report on the feasibility from the • EURISOL DS soon available. • Future studies (ex. ion intensity within EUROnu). Conclusions Neutrinos in core-collapse supernovae : We have set the basis for the exploration of CP violation in dense media.

  31. Danke. Thank you! Andromeda (M31) Grazie. Merci.

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