Sample records for majorana neutrinos neutrino

  1. Double Beta Decay and Majorana Neutrino

    Microsoft Academic Search

    Masaru Doi; Tsuneyuki Kotani; Eiichi Takasugi

    1985-01-01

    This review consists of three parts: Various properties of the quantized neutrino fields are summarized in part I from the viewpoint that a Dirac neutrino consists of two Majorana neutrinos with a degenerate mass but with opposite CP sings. It is shown why the Dirac neutrino has a freedom of the phase transformation to guarantee the lepton number conservation, while

  2. FCNC, CP violation, and impure Majorana neutrinos

    E-print Network

    Dan-Di Wu

    1997-01-24

    The tree level diagonalization of a neutrino mass matrix with both Majorana and Dirac masses is discussed in a general context. Flavor changing neutral currents in such models are inevitable. Rephasing invariant quantities characterizing CP violation in FCNC Fermion-Higgs interactions are identified. At the one loop level, the mass eigenstates become an impure Majorana type. The possibility of a significant change in the mass spectrum for the left-handed neutrinos is explored, with an example of two species of neutrinos. Neutrino oscillations with impure Majorana neutrinos are also discussed.

  3. Triangle Inequalities for Majorana-Neutrino Magnetic Moments

    E-print Network

    Jean-Marie Frère; Julian Heeck; Simon Mollet

    2015-06-09

    Electromagnetic properties of neutrinos, if ever observed, could help to decide the Dirac versus Majorana nature of neutrinos. We show that the magnetic moments of Majorana neutrinos have to fulfill triangle inequalities, $|\\mu_{\

  4. Triangle Inequalities for Majorana-Neutrino Magnetic Moments

    E-print Network

    Frère, Jean-Marie; Mollet, Simon

    2015-01-01

    Electromagnetic properties of neutrinos, if ever observed, could help to decide the Dirac versus Majorana nature of neutrinos. We show that the magnetic moments of Majorana neutrinos have to fulfill triangle inequalities, $|\\mu_{\

  5. Signatures for Majorana neutrinos at hadron colliders

    E-print Network

    Tao Han; Bin Zhang

    2006-10-28

    The Majorana nature of neutrinos may only be experimentally verified via lepton-number violating processes involving charged leptons. We explore the $\\Delta L=2$ like-sign dilepton production at hadron colliders to search for signals of Majorana neutrinos. We find significant sensitivity for resonant production of a Majorana neutrino in the mass range of 10-80 GeV at the current run of the Tevatron with 2 fb$^{-1}$ integrated luminosity, and in the range of 10-400 GeV at the LHC with 100 fb$^{-1}$.

  6. Search for Majorana neutrinos in B- ? ?+ ?- ?- decays.

    PubMed

    Aaij, R; Adeva, B; Adinolfi, M; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves, A A; Amato, S; Amerio, S; Amhis, Y; Anderlini, L; Anderson, J; Andreassen, R; Andreotti, M; Andrews, J E; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Baalouch, M; Bachmann, S; Back, J J; Badalov, A; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Batozskaya, V; Bauer, T; Bay, A; Beddow, J; Bedeschi, F; Bediaga, I; Belogurov, S; Belous, K; Belyaev, I; Ben-Haim, E; Bencivenni, G; Benson, S; Benton, J; Berezhnoy, A; Bernet, R; Bettler, M-O; van Beuzekom, M; Bien, A; Bifani, S; Bird, T; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blouw, J; Blusk, S; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Borsato, M; Bowcock, T J V; Bowen, E; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Britsch, M; Britton, T; Brook, N H; Brown, H; Bursche, A; Busetto, G; Buytaert, J; Cadeddu, S; Calabrese, R; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Campora Perez, D; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carranza-Mejia, H; Carson, L; Carvalho Akiba, K; Casse, G; Castillo Garcia, L; Cattaneo, M; Cauet, C; Cenci, R; Charles, M; Charpentier, P; Cheung, S-F; Chiapolini, N; Chrzaszcz, M; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coca, C; Coco, V; Cogan, J; Cogneras, E; Collins, P; Comerma-Montells, A; Contu, A; Cook, A; Coombes, M; Coquereau, S; Corti, G; Counts, I; Couturier, B; Cowan, G A; Craik, D C; Cruz Torres, M; Cunliffe, S; Currie, R; D'Ambrosio, C; Dalseno, J; David, P; David, P N Y; Davis, A; De Bonis, I; De Bruyn, K; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Silva, W; De Simone, P; Decamp, D; Deckenhoff, M; Del Buono, L; Déléage, N; Derkach, D; Deschamps, O; Dettori, F; Di Canto, A; Dijkstra, H; Donleavy, S; Dordei, F; Dorigo, M; Dorosz, P; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Durante, P; Dzhelyadin, R; Dziurda, A; Dzyuba, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; Eisenhardt, S; Eitschberger, U; Ekelhof, R; Eklund, L; El Rifai, I; Elsasser, C; Falabella, A; Färber, C; Farinelli, C; Farry, S; Ferguson, D; Fernandez Albor, V; Ferreira Rodrigues, F; Ferro-Luzzi, M; Filippov, S; Fiore, M; Fiorini, M; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Francisco, O; Frank, M; Frei, C; Frosini, M; Furfaro, E; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garofoli, J; Garra Tico, J; Garrido, L; Gaspar, C; Gauld, R; Gersabeck, E; Gersabeck, M; Gershon, T; Ghez, P; Gianelle, A; Gibson, V; Giubega, L; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Griffith, P; Grillo, L; Grünberg, O; Gui, B; Gushchin, E; Guz, Y; Gys, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Hafkenscheid, T W; Haines, S C; Hall, S; Hamilton, B; Hampson, T; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; Hartmann, T; He, J; Head, T; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Heß, M; Hicheur, A; Hill, D; Hoballah, M; Hombach, C; Hulsbergen, W; Hunt, P; Huse, T; Hussain, N; Hutchcroft, D; Hynds, D; Iakovenko, V; Idzik, M; Ilten, P; Jacobsson, R; Jaeger, A; Jans, E; Jaton, P; Jawahery, A; Jing, F; John, M; Johnson, D; Jones, C R; Joram, C; Jost, B; Jurik, N; Kaballo, M; Kandybei, S; Kanso, W; Karacson, M; Karbach, T M; Kenyon, I R; Ketel, T; Khanji, B; Khurewathanakul, C; Klaver, S; Kochebina, O; Komarov, I; Koopman, R F; Koppenburg, P; Korolev, M; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kucharczyk, M; Kudryavtsev, V; Kurek, K; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Latham, T; Lazzeroni, C; Le Gac, R; van Leerdam, J; Lees, J-P; Lefèvre, R; Leflat, A; Lefrançois, J; Leo, S; Leroy, O; Lesiak, T; Leverington, B; Li, Y; Liles, M; Lindner, R; Linn, C; Lionetto, F; Liu, B; Liu, G; Lohn, S; Longstaff, I; Lopes, J H; Lopez-March, N; Lowdon, P; Lu, H; Lucchesi, D; Luisier, J; Luo, H; Luppi, E; Lupton, O; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Malde, S; Manca, G; Mancinelli, G; Manzali, M; Maratas, J; Marconi, U; Marino, P; Märki, R; Marks, J; Martellotti, G; Martens, A; Martín Sánchez, A; Martinelli, M; Martinez Santos, D; Martins Tostes, D; Massafferri, A; Matev, R; Mathe, Z; Matteuzzi, C; Mazurov, A; McCann, M; McCarthy, J; McNab, A; McNulty, R; McSkelly, B; Meadows, B; Meier, F; Meissner, M; Merk, M; Milanes, D A; Minard, M-N; Molina Rodriguez, J; Monteil, S; Moran, D; Morandin, M

    2014-04-01

    A search for heavy Majorana neutrinos produced in the B- ? ?+ ?- ?- decay mode is performed using 3??fb(-1) of integrated luminosity collected with the LHCb detector in pp collisions at center-of-mass energies of 7 and 8 TeV at the LHC. Neutrinos with masses in the range 250 to 5000 MeV and lifetimes from zero to 1000 ps are probed. In the absence of a signal, upper limits are set on the branching fraction B(B- ? ?+ ?- ?-) as functions of neutrino mass and lifetime. These limits are on the order of 10(-9) for short neutrino lifetimes of 1 ps or less. Limits are also set on the coupling between the muon and a possible fourth-generation neutrino. PMID:24745405

  7. Can neutrino-electron scattering tell us whether neutrinos are Dirac or Majorana particles

    SciTech Connect

    Kayser, B.

    1988-04-01

    There has recently been interest in the possibility that neutrino-electron scattering experiments could determine whether neutrinos are Dirac or Majorana particles by providing information on their electromagnetic structure. We try to explain why studies of neutrino electromagnetic structure actually cannot distinguish between Dirac and Majorana neutrinos. 9 refs.

  8. Majorana neutrino masses from neutrinoless double beta decay and cosmology

    Microsoft Academic Search

    V. Barger; K. Whisnant

    1999-01-01

    When three Majorana neutrinos describe the solar and atmospheric neutrino data via oscillations, a nonzero measurement of neutrinoless double beta (0???) decay can determine the sum of neutrino masses ?m? if the solar solution has small-angle mixing, and place a lower bound on ?m? for large-angle solar mixing. If in addition a nonzero ?m? is deduced from cosmology, the neutrino

  9. Dirac- and Majorana-neutrino-mass effects in neutrino-electron elastic scattering

    SciTech Connect

    Garavaglia, T.

    1984-02-01

    A covariant formulation is given for the mass-dependent differential cross sections for neutrino (antineutrino)-electron elastic scattering with either Dirac or Majorana neutrinos. It is explained how these cross sections along with a formulation for neutrino oscillations may be used to describe the helicity-transformation effect for neutrinos passing through matter.

  10. Geometry of Majorana neutrino and new symmetries

    E-print Network

    Volkov, G G

    2006-01-01

    Experimental observation of Majorana fermion matter gives a new impetus to the understanding of the Lorentz symmetry and its extension, the geometrical properties of the ambient space-time structure, matter--antimatter symmetry and some new ways to understand the baryo-genesis problem in cosmology. Based on the primordial Majorana fermion matter assumption, we discuss a possibility to solve the baryo-genesis problem through the the Majorana-Diraco genesis in which we have a chance to understand creation of Q(em) charge and its conservation in our D=1+3 Universe after the Big Bang. In the Majorana-Diraco genesis approach there appears a possibility to check the proton and electron non-stability on the very low energy scale. In particle physics and in our space-time geometry, the Majorana nature of the neutrino can be related to new types of symmetries which are lying beyond the binary Cartan-Killing-Lie algebras/superalgebras. This can just support a conjecture about the non-completeness of the SM in terms of ...

  11. The Majorana neutrino mass matrix indicated by the current data

    NASA Astrophysics Data System (ADS)

    Zhang, XinYi; Ma, BoQiang

    2015-07-01

    The Majorana neutrino mass matrix combines information from the neutrino masses and the leptonic mixing in the flavor basis. Its invariance under some transformation matrices indicates the existence of certain residual symmetry. We offer an intuitive display of the structure of the Majorana neutrino mass matrix, using the whole set of the oscillation data. The structure is revealed depending on the lightest neutrino mass. We find that there are three regions with distinct characteristics of structure. A group effect and the µ- ? exchange symmetry are observed. Six types of texture non-zeros are shown. Implications for flavor models are discussed.

  12. Discriminating Majorana Neutrino Textures in the light of Baryon Asymmetry

    E-print Network

    Borah, Manikanta; Das, Mrinal Kumar

    2015-01-01

    We study all possible texture zeros in the Majorana neutrino mass matrix which are allowed from neutrino oscillation as well as cosmology data when the charged lepton mass matrix is assumed to take the diagonal form. Considering two different possible values of the lightest neutrino mass giving rise to quasi-degenerate and hierarchical light neutrino mass spectrum respectively, we write down the Majorana CP phases as a function of the Dirac CP phase using the constraints coming from vanishing or equality of elements in a particular texture zero mass matrix. We constrain texture zero mass matrices from the requirement of producing correct baryon asymmetry through the mechanism of leptogenesis. Adopting a type I seesaw framework, we consider the CP violating out of equilibrium decay of the lightest right handed neutrino as the source of lepton asymmetry. Apart from discriminating between the texture zero mass matrices and light neutrino mass hierarchy, we also constrain the Dirac CP phase so that the observed b...

  13. Can Gravity Distinguish between Dirac and Majorana Neutrinos?

    SciTech Connect

    Singh, Dinesh; Mobed, Nader [Department of Physics, University of Regina, Regina, Saskatchewan, S4S 0A2 (Canada); Papini, Giorgio [Department of Physics, University of Regina, Regina, Saskatchewan, S4S 0A2 (Canada); Prairie Particle Physics Institute, Regina, Saskatchewan, S4S 0A2 (Canada); International Institute for Advanced Scientific Studies, 89019 Vietri sul Mare (Saudi Arabia) (Italy)

    2006-07-28

    We show that spin-gravity interaction can distinguish between Dirac and Majorana neutrino wave packets propagating in a Lense-Thirring background. Using time-independent perturbation theory and the gravitational phase to generate a perturbation Hamiltonian with spin-gravity coupling, we show that the associated matrix element for the Majorana neutrino differs significantly from its Dirac counterpart. This difference can be demonstrated through significant gravitational corrections to the neutrino oscillation length for a two-flavor system, as shown explicitly for SN 1987A.

  14. Discriminating Majorana neutrino textures in light of the baryon asymmetry

    NASA Astrophysics Data System (ADS)

    Borah, Manikanta; Borah, Debasish; Das, Mrinal Kumar

    2015-06-01

    We study all possible texture zeros in the Majorana neutrino mass matrix which are allowed from neutrino oscillation as well as cosmology data when the charged lepton mass matrix is assumed to take the diagonal form. In the case of one-zero texture, we write down the Majorana phases which are assumed to be equal and the lightest neutrino mass as a function of the Dirac C P phase. In the case of two-zero texture, we numerically evaluate all the three C P phases and lightest neutrino mass by solving four real constraint equations. We then constrain texture zero mass matrices from the requirement of producing correct baryon asymmetry through the mechanism of leptogenesis by assuming the Dirac neutrino mass matrix to be diagonal. Adopting a type I seesaw framework, we consider the C P -violating out of equilibrium decay of the lightest right-handed neutrino as the source of lepton asymmetry. Apart from discriminating between the texture zero mass matrices and light neutrino mass hierarchy, we also constrain the Dirac and Majorana C P phases so that the observed baryon asymmetry can be produced. In two-zero texture, we further constrain the diagonal form of the Dirac neutrino mass matrix from the requirement of producing correct baryon asymmetry.

  15. CP properties of the leptonic sector for Majorana neutrinos

    NASA Astrophysics Data System (ADS)

    Bernabéu, J.; Pascual, P.

    1983-11-01

    The leptonic sector of the electroweak theory is analyzed for massive Majorana neutrinos. For n generations, the Majorana mass lagrangian is diagonalized using the polar reduction to guarantee physical positive masses independently of the CP properties or the choice of the phases of the fields. When CP invariance holds, the CP eigenvalues of the definite mass neutrino fields are determined without commitment to a particular phase choice. For charged current interactions, we find that the observable CP violating phases can be parametrized à la Kobayashi-Maskawa for the vertec. Extra ( n - 1) relative phases of the massive neutrino fields are significant. The extra phases are observable only in processes mediated by "neutrino-antineutrino" propagation and therefore proportional to neutrino masses. We discuss the informational content of the relevant processes.

  16. Double beta decay, Majorana neutrinos, and neutrino mass Frank T. Avignone III*

    E-print Network

    Engel, Jonathan

    Double beta decay, Majorana neutrinos, and neutrino mass Frank T. Avignone III* Department The theoretical and experimental issues relevant to neutrinoless double beta decay are reviewed. The impact more sensitive, even the nonobservation of neutrinoless double beta decay will be useful

  17. From transition magnetic moments to majorana neutrino masses

    E-print Network

    Sacha Davidson; Martin Gorbahn; Arcadi Santamaria

    2005-10-12

    It is well known that a majorana mass induces a (small) transition magnetic moment. The converse is also true; in this paper we estimate the loop contribution of transition magnetic moments $[\\mu]_{\\alpha \\beta}$ to the neutrino mass matrix $[m]_{\\alpha \\beta}$. We show that for hierarchical neutrino masses, the contribution of $[\\mu]_{e \\tau}$ to $[m]_{e \\tau}$ can exceed the experimental value of $[m]_{e \\tau}$.

  18. Neutrinos

    E-print Network

    A. de Gouvea; K. Pitts; K. Scholberg; G. P. Zeller; J. Alonso; A. Bernstein; M. Bishai; S. Elliott; K. Heeger; K. Hoffman; P. Huber; L. J. Kaufman; B. Kayser; J. Link; C. Lunardini; B. Monreal; J. G. Morfin; H. Robertson; R. Tayloe; N. Tolich; K. Abazajian; T. Akiri; C. Albright; J. Asaadi; K. S Babu; A. B. Balantekin; P. Barbeau; M. Bass; A. Blake; A. Blondel; E. Blucher; N. Bowden; S. J. Brice; A. Bross; B. Carls; F. Cavanna; B. Choudhary; P. Coloma; A. Connolly; J. Conrad; M. Convery; R. L. Cooper; D. Cowen; H. da Motta; T. de Young; F. Di Lodovico; M. Diwan; Z. Djurcic; M. Dracos; S. Dodelson; Y. Efremenko; T. Ekelof; J. L. Feng; B. Fleming; J. Formaggio; A. Friedland; G. Fuller; H. Gallagher; S. Geer; M. Gilchriese; M. Goodman; D. Grant; G. Gratta; C. Hall; F. Halzen; D. Harris; M. Heffner; R. Henning; J. L. Hewett; R. Hill; A. Himmel; G. Horton-Smith; A. Karle; T. Katori; E. Kearns; S. Kettell; J. Klein; Y. Kim; Y. K. Kim; Yu. Kolomensky; M. Kordosky; Yu. Kudenko; V. A. Kudryavtsev; K. Lande; K. Lang; R. Lanza; K. Lau; H. Lee; Z. Li; B. R. Littlejohn; C. J. Lin; D. Liu; H. Liu; K. Long; W. Louis; K. B. Luk; W. Marciano; C. Mariani; M. Marshak; C. Mauger; K. T. McDonald; K. McFarland; R. McKeown; M. Messier; S. R. Mishra; U. Mosel; P. Mumm; T. Nakaya; J. K. Nelson; D. Nygren; G. D. Orebi Gann; J. Osta; O. Palamara; J. Paley; V. Papadimitriou; S. Parke; Z. Parsa; R. Patterson; A. Piepke; R. Plunkett; A. Poon; X. Qian; J. Raaf; R. Rameika; M. Ramsey-Musolf; B. Rebel; R. Roser; J. Rosner; C. Rott; G. Rybka; H. Sahoo; S. Sangiorgio; D. Schmitz; R. Shrock; M. Shaevitz; N. Smith; M. Smy; H. Sobel; P. Sorensen; A. Sousa; J. Spitz; T. Strauss; R. Svoboda; H. A. Tanaka; J. Thomas; X. Tian; R. Tschirhart; C. Tully; K. Van Bibber; R. G. Van de Water; P. Vahle; P. Vogel; C. W. Walter; D. Wark; M. Wascko; D. Webber; H. Weerts; C. White; H. White; L. Whitehead; R. J. Wilson; L. Winslow; T Wongjirad; E. Worcester; M. Yokoyama; J. Yoo; E. D. Zimmerman

    2013-10-16

    This document represents the response of the Intensity Frontier Neutrino Working Group to the Snowmass charge. We summarize the current status of neutrino physics and identify many exciting future opportunities for studying the properties of neutrinos and for addressing important physics and astrophysics questions with neutrinos.

  19. CP violation with Majorana neutrinos in K meson decays

    NASA Astrophysics Data System (ADS)

    Dib, Claudio O.; Campos, Miguel; Kim, C. S.

    2015-02-01

    We study the possibility of having CP asymmetries in the decay K ± ? ? ? ? ± ? ± ( ? = e, ?). This decay violates Lepton Number by two units and occurs only if there are Majorana particles that mediate the transition. Even though the absolute rate is highly suppressed by current bounds, we search for Majorana neutrino scenarios where the CP asymmetry arising from the lepton sector could be sizeable. This is indeed the case if there are two or more Majorana neutrinos with similar masses in the range around 102 MeV. In particular, the asymmetry is potentially near unity if two neutrinos are nearly degenerate, in the sense ? m N ˜ ? N . The full decay, however, may be difficult to detect not only because of the suppression caused by the heavy-to-light lepton mixing, but also because of the long lifetime of the heavy neutrino, which would induce large space separation between the two vertices where the charge leptons are produced. This particular problem should be less serious in heavier meson decays, as they involve heavier neutrinos with shorter lifetimes.

  20. Distinguishing between Dirac and Majorana neutrinos withtwo-particle interferometry

    SciTech Connect

    Gutierrez, Thomas D.

    2006-03-02

    Two-particle interferometry, a second-order interferenceeffect, is explored as another possible tool to distinguish betweenmassive Dirac and Majorana neutrinos. A simple theoretical framework isdiscussed in the context of several gedanken experiments. The method canin principle provide both the mass scale and the quantum nature of theneutrino for a certain class of incoherent left-handed sourcecurrents.

  1. Double beta decay, Majorana neutrinos, and neutrino mass

    SciTech Connect

    Avignone, Frank T. III; Elliott, Steven R.; Engel, Jonathan [Department of Physics and Astronomy, University of South Carolina, Columbia, South Carolina 29208 (United States); Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27599-3255 (United States)

    2008-04-15

    The theoretical and experimental issues relevant to neutrinoless double beta decay are reviewed. The impact that a direct observation of this exotic process would have on elementary particle physics, nuclear physics, astrophysics, and cosmology is profound. Now that neutrinos are known to have mass and experiments are becoming more sensitive, even the nonobservation of neutrinoless double beta decay will be useful. If the process is actually observed, we will immediately learn much about the neutrino. The status and discovery potential of proposed experiments are reviewed in this context, with significant emphasis on proposals favored by recent panel reviews. The importance of and challenges in the calculation of nuclear matrix elements that govern the decay are considered in detail. The increasing sensitivity of experiments and improvements in nuclear theory make the future exciting for this field at the interface of nuclear and particle physics.

  2. Double beta decay, Majorana neutrinos, and neutrino mass

    Microsoft Academic Search

    Frank T. Avignone III; Steven R. Elliott; Jonathan Engel

    2008-01-01

    The theoretical and experimental issues relevant to neutrinoless double-beta\\u000adecay are reviewed. The impact that a direct observation of this exotic process\\u000awould have on elementary particle physics, nuclear physics, astrophysics and\\u000acosmology is profound. Now that neutrinos are known to have mass and\\u000aexperiments are becoming more sensitive, even the non-observation of\\u000aneutrinoless double-beta decay will be useful. If

  3. General Majorana Neutrino Mass Matrix from a Low Energy SU(3) Family Symmetry with Sterile Neutrinos

    E-print Network

    Albino Hernandez-Galeana

    2014-12-20

    Within the framework of a local SU(3) family symmetry model, we report a general analysis of the mechanism for neutrino mass generation and mixing, including light sterile neutrinos. In this scenario, ordinary heavy fermions, top and bottom quarks and tau lepton, become massive at tree level from Dirac See-saw mechanisms implemented by the introduction of a new set of $SU(2)_L$ weak singlet vector-like fermions, U,D,E,N, with N a sterile neutrino. Right-handed and the $N_{L,R}$ sterile neutrinos allow the implementation of a 8x8 general Majorana neutrino mass matrix with four or five massless neutrinos at tree level. Hence, light fermions, including light neutrinos get masses from radiative corrections mediated by the massive SU(3) gauge bosons. We report the corresponding Majorana neutrino mass matrix up to one loop. Previous numerical analysis of the free parameters show out solutions for quarks and charged lepton masses within a parameter space region where the vector-like fermion masses $M_U, M_D, M_E$, and the SU(3) family gauge boson masses lie in the low energy region of $\\mathcal{O} (1-20)\\,$TeV, with light neutrinos within the correct order of square neutrino mass differences: $m_2^2-m_1^2 \\approx 7 \\times 10^{-5}\\;\\text{eV}^2$, $m_3^2-m_1^2 \\approx 2 \\times 10^{-3}\\;\\text{eV}^2$, and at least one sterile neutrino of the order $\\approx 0.5\\;\\text{eV}$. A more precise fit of the parameters is still needed to account also for the quark and lepton mixing.

  4. Search for Majorana neutrinos with the SNO+ detector at SNOLAB

    NASA Astrophysics Data System (ADS)

    Maio, A.; SNO+ collaboration

    2015-02-01

    The SNO+ experiment is adapting the Sudbury Neutrino Observatory (SNO) detector, in order to use isotope-loaded liquid scintillator as the active medium. SNO+ has multiple scientific goals, the main one being the search for neutrinoless double beta decay, the most promising signature for the possible Majorana character of neutrinos and for the absolute neutrino mass. Measurements of neutrinos from the Sun, the Earth, Supernovae and nuclear reactors are additional goals of the experiment. The detector consists of a 12m diameter spherical vessel, filled with 780 tonnes of Tellurium-loaded liquid scintillator, and surrounded by about 9500 PMTs. It is shielded by a large volume of ultra-pure water and the underground location at SNOLAB, Canada. This talk will review the Physics goals and current status of SNO+.

  5. Neutrinos

    PubMed Central

    Besson, Dave; Cowen, Doug; Selen, Mats; Wiebusch, Christopher

    1999-01-01

    Neutrinos represent a new “window” to the Universe, spanning a large range of energy. We discuss the science of neutrino astrophysics and focus on two energy regimes. At “lower” energies (?1 MeV), studies of neutrinos born inside the sun, or produced in interactions of cosmic rays with the atmosphere, have allowed the first incontrovertible evidence that neutrinos have mass. At energies typically one thousand to one million times higher, sources further than the sun (both within the Milky Way and beyond) are expected to produce a flux of particles that can be detected only through neutrinos. PMID:10588680

  6. Constraints from neutrino oscillation experiments on the effective Majorana mass in neutrinoless double beta-decay

    Microsoft Academic Search

    S. M. Bilenky; S. T. Petcov

    1999-01-01

    We determine the possible values of the effective Majorana neutrino mass $| |= |\\\\sum_j U_{ej}^2 m_j|$ in the different phenomenologically viable three and four-neutrino scenarios. The quantities $U_{\\\\alpha j}$ ($\\\\alpha = e,\\\\mu,\\\\tau,...$) denote the elements of the neutrino mixing matrix and the Majorana neutrino masses $m_j$ ($j=1,2,3,...$) are ordered as $m_1 < m_2 < ... $ Assuming $m_1 \\\\ll m_3$

  7. Majorana neutrino masses and the neutrinoless double-beta decay

    Microsoft Academic Search

    A. Faessler

    2006-01-01

    Neutrinoless double-beta decay is forbidden in the Standard Model of electroweak and strong interaction but allowed in most\\u000a Grand Unified Theories (GUTs). Only if the neutrino is a Majorana particle (identical with its antiparticle) and if it has\\u000a a mass is neutrinoless double-beta decay allowed. Apart from one claim that the neutrinoless double-beta decay in 76Ge is measured, one has

  8. Ettore Majorana centennial and neutrino legacy

    NASA Astrophysics Data System (ADS)

    Esposito, Salvatore

    2007-06-01

    "In the world there are various categories of scientists: people of secondary or tertiary standing, who do their best but do not go very far. There are also those of high standing, who come to discoveries of great importance. But then there are geniuses like Galileo and Newton. Well, Ettore was one of them. Majorana had what no one else in the world has...". In this talk we try to put some light on this quite unusual statement by Enrico Fermi about Ettore Majorana, by exploring mainly personal notes left unpublished by the great sicilian physicist. Some emphasis is given on recent achievements about Majorana as a research scientist as well as a teacher in Theoretical Physics.

  9. Majorana phases, CP violation, sterile neutrinos and neutrinoless double-beta decay

    SciTech Connect

    Babi?, Andrej [Department of Nuclear Physics and Biophysics, Faculty of Mathematics, Physics and Informatics, Comenius University, Mlynská dolina, 842 48 Bratislava (Slovakia); Šimkovic, Fedor [Bogoliubov Laboratory of Theoretical Physics, JINR, Joliot-Curie 6, 141980 Dubna, Moscow region, Russia and Institute of Experimental and Applied Physics, Czech Technical University, CZ-128 00 Prague (Czech Republic)

    2013-12-30

    CP violation plays a crucial role in the generation of the baryon asymmetry in the Universe. Within this context we investigate the possibility of CP violation in the lepton sector caused by Majorana neutrino mixing. Focus is put on the model including 1 sterile neutrino. Both cases of normal and inverted neutrino mass spectrum are considered. We address the question whether the Majorana phases can be measured in the neutrinoless double-beta decay experiments with sensitivity to the effective Majorana neutrino mass of the order of 10{sup ?2} eV.

  10. Majorana Neutrinos, Neutrino Mass Spectrum and the || ~ 0.001 eV Frontier in Neutrinoless Double Beta Decay

    E-print Network

    S. Pascoli; S. T. Petcov

    2007-11-30

    If future neutrino oscillation experiments show that the neutrino mass spectrum is with normal ordering, m1 | > 0.01 eV give negative results, the next frontier in the quest for neutrinoless double beta-decay will correspond to || ~ 0.001 eV. Assuming that massive neutrinos are Majorana particles and their exchange is the dominant mechanism generating neutrinoless double beta-decay, we analise the conditions under which ||, in the case of three neutrino mixing and neutrino mass spectrum with normal ordering, would satisfy || > 0.001 eV. We consider the specific cases of i) normal hierarchical neutrino mass spectrum, ii) of relatively small value of the CHOOZ angle theta13 as well as iii) the general case of spectrum with normal ordering, partial hierarchy and a value of theta13 close to the existing upper limit. We study the ranges of the lightest neutrino mass m1 and/or of sin^2 theta13, for which ||> 0.001 eV and discuss the phenomenological implications of such scenarios. We provide also an estimate of || when the three neutrino masses and the neutrino mixing originate from neutrino mass term of Majorana type for the (left-handed) flavour neutrinos and m1 Ue1^2 + m2 U_e2^2 + m3 Ue3^2 =0, but there does not exist a symmetry which forbids the neutrinoless double beta-decay.

  11. Heavy Majorana Neutrinos from $W?$ Fusion at Hadron Colliders

    E-print Network

    Daniel Alva; Tao Han; Richard Ruiz

    2015-02-25

    Vector boson fusion processes become increasingly more important at higher collider energies and for probing larger mass scales due to collinear logarithmic enhancements of the cross section. In this context, we revisit the production of a hypothetic heavy Majorana neutrino $(N)$ at hadron colliders. Particular attention is paid to the fusion process $W\\gamma \\rightarrow N\\ell^{\\pm}$. We systematically categorize the contributions from an initial state photon in the elastic, inelastic, and deeply inelastic channels. Comparing with the leading channel via the Drell-Yan production $q \\bar{q}'\\rightarrow W^{*}\\rightarrow N\\ell^{\\pm}$ at NNLO in QCD, we find that the $W\\gamma$ fusion process becomes relatively more important at higher scales, surpassing the DY mechanism at $m_{N} \\sim 1 \\text{TeV} \\ (770 \\text{GeV})$ at the 14 TeV LHC (100 TeV VLHC). We investigate the inclusive heavy Majorana neutrino signal, including QCD corrections, and quantify the Standard Model backgrounds at future hadron colliders. We conclude that, with the currently allowed mixing $| V_{\\mu N}| ^2VLHC) after 1 ab$^{-1}$. Reversely, for $m_N = 500$ GeV and the same integrated luminosity, a mixing $| V_{\\mu N}|^2$ of the order $1.1\\times10^{-3} (2.5\\times10^{-4})$ may be probed.

  12. Heavy Majorana neutrinos from W? fusion at hadron colliders

    NASA Astrophysics Data System (ADS)

    Alva, Daniel; Han, Tao; Ruiz, Richard

    2015-02-01

    Vector boson fusion processes become increasingly more important at higher collider energies and for probing larger mass scales due to collinear logarithmic enhancements of the cross section. In this context, we revisit the production of a hypothetic heavy Majorana neutrino ( N) at hadron colliders. Particular attention is paid to the fusion process W? ? N? ±. We systematically categorize the contributions from a photon initial state in the elastic, inelastic, and deeply inelastic channels. Comparing with the leading channel via the Drell-Yan production ? W * ? N? ± at NNLO in QCD, we find that the W? fusion process becomes relatively more important at higher scales, surpassing the DY mechanism at m N ˜ 1 TeV (770 GeV), at the 14 TeV LHC (100 TeV VLHC). We investigate the inclusive heavy Majorana neutrino signal, including QCD corrections, and quantify the Standard Model backgrounds at future hadron colliders. We conclude that, with the currently allowed mixing | V ?N |2 < 6 × 10-3, a 5 ? discovery can be made via the same-sign dimuon channel for m N = 530 (1070) GeV at the 14 TeV LHC (100 TeV VLHC) after 1 ab-1. Reversely, for m N = 500 GeV and the same integrated luminosity, a mixing | V ?N |2 of the order 1.1 × 10-3 (2.5 × 10-4) may be probed.

  13. Probing the Majorana nature of the neutrino with neutrinoless double beta decay

    E-print Network

    S. Morisi

    2009-10-14

    Neutrinoless double beta decay (NDBD) is the only experiment that could probe the Majorana nature of the neutrino. Here we study the theoretical implications of NDBD for models yielding tri-bimaximal lepton mixing like A4 and S4.

  14. Search for Majorana Neutrinos in B[superscript ?] ? ?[superscript +]?[superscript ?]?[superscript ?] Decays

    E-print Network

    Counts, Ian Thomas Hunt

    A search for heavy Majorana neutrinos produced in the B[superscript ?] ? ?[superscript +]?[superscript ?]?[superscript ?] decay mode is performed using 3??fb[superscript ?1] of integrated luminosity collected with the LHCb ...

  15. Search for Majorana neutrinos with the first two years of EXO-200 data

    E-print Network

    EXO-200 Collaboration; :; J. B. Albert; D. J. Auty; P. S. Barbeau; E. Beauchamp; D. Beck; V. Belov; C. Benitez-Medina; J. Bonatt; M. Breidenbach; T. Brunner; A. Burenkov; G. F. Cao; C. Chambers; J. Chaves; B. Cleveland; M. Coon; A. Craycraft; T. Daniels; M. Danilov; S. J. Daugherty; C. G. Davis; J. Davis; R. DeVoe; S. Delaquis; T. Didberidze; A. Dolgolenko; M. J. Dolinski; M. Dunford; W. Fairbank Jr.; J. Farine; W. Feldmeier; P. Fierlinger; D. Fudenberg; G. Giroux; R. Gornea; K. Graham; G. Gratta; C. Hall; S. Herrin; M. Hughes; M. J. Jewell; X. S. Jiang; A. Johnson; T. N. Johnson; S. Johnston; A. Karelin; L. J. Kaufman; R. Killick; T. Koffas; S. Kravitz; A. Kuchenkov; K. S. Kumar; D. S. Leonard; F. Leonard; C. Licciardi; Y. H. Lin; R. MacLellan; M. G. Marino; B. Mong; D. Moore; R. Nelson; A. Odian; I. Ostrovskiy; C. Ouellet; A. Piepke; A. Pocar; C. Y. Prescott; A. Rivas; P. C. Rowson; M. P. Rozo; J. J. Russell; A. Schubert; D. Sinclair; S. Slutsky; E. Smith; V. Stekhanov; M. Tarka; T. Tolba; D. Tosi; K. Twelker; P. Vogel; J. -L. Vuilleumier; A. Waite; J. Walton; T. Walton; M. Weber; L. J. Wen; U. Wichoski; J. D. Wright; L. Yang; Y. -R. Yen; O. Ya. Zeldovich; Y. B. Zhao

    2014-06-04

    Many extensions of the Standard Model of particle physics suggest that neutrinos should be Majorana-type fermions, but this assumption is difficult to confirm. Observation of neutrinoless double-beta decay ($0\

  16. The search for Majorana neutrinos with neutrinoless double beta decays: From CUORICINO to LUCIFER experiment

    SciTech Connect

    Bellini, F. [Dipartimento di Fisica, Sapienza Universita di Roma, Roma I-00185 (Italy) and INFN - Sezione di Roma, Roma I-00185 (Italy)

    2012-11-20

    The study of neutrino properties is one of the fundamental challenges in particle physics nowadays. Fifty years of investigations established that neutrinos are massive but the absolute mass scale has not yet been measured. Moreover its true nature is still unknown. Is the neutrino its own antiparticle (thus violating the lepton number) as proposed by Majorana in 1937? The only way to probe the neutrino nature is through the observation of Neutrinoless Double Beta Decay (0{nu}{beta}{beta}), a very rare spontaneous nuclear transition which emits two electrons and no neutrinos. In this paper, after a brief introduction to the theoretical framework of Majorana's neutrino, a presentation of experimental challenges posed by 0{nu}{beta}{beta} search will be given as well as an overview of present status and future perpectives of experiments.

  17. Same-sign dileptons as a signature for heavy Majorana neutrinos in hadron-hadron collisions

    E-print Network

    F. M. L. Almeida Jr; Y. A. Coutinho; J. A. Martins Simões; P. P. Queiroz Filho; C. M. Porto

    1997-03-27

    We discuss the possibility of same-sign dileptons as a signature for Majorana neutrinos. The production mechanism is given by a single heavy neutrino production and decay proton-proton -> l^{\\pm} N X -> l^{\\pm} l^{\\pm} X'. Cross section and distributions are presented for the LHC energies.

  18. Are massive Majorana neutrinos canceling each other in neutrinoless double-. beta. decay

    SciTech Connect

    Vergados, J.D.

    1983-12-01

    The possibility of various massive Majorana neutrinos canceling each other in neutrinoless double-..beta.. decay is examined. It is shown that if all neutrino eigenmasses are less than 10 MeV such a cancellation persists in the hadronic medium if initially present at the elementary (gauge) level. The same is true for neutrino mass greater than 10 GeV. In all other cases, such a cancellation will require a conspiracy between particle and nuclear physics.

  19. Neutrino

    NASA Astrophysics Data System (ADS)

    Han, Yongquan

    2015-04-01

    The most basic Quantum are the particles who mutual rotation, quantum is composed of basic quantum.Quantum convergence or divergence is conditional, the faster the particle rotates, the smaller the orbiting radius will be, the greater quality is, the more density will be. The orbiting radius of less than 10-15 meters in the order of convergence, convergence of neutron, proton, and then they are in the formation of the nucleus, and the convergence of quantum can make extra nuclear electron and the formation of atomic; if rotation radius is more than 10-15 meters of magnitude, the internal quantum atoms diverge to outer space in the form of electromagnetic waves. The quality of magnetic wave particle is composed of the rotation speed of the particle which is internal of the electromagnetic, it doesn't matter about the electromagnetic wave propagation velocity of particles. Neutrinos are orbiting particles, the orbiting radius is about 10-15 meters, is a special kind of radiation. Neutrino is between the virtual particles (according to modern science, the electromagnetic wave doesn't have quality) and modern scientific (the particle who has quality) special particles

  20. A Combined Limit on the Neutrino Mass from Neutrinoless Double-Beta Decay and Constraints on Sterile Majorana Neutrinos

    E-print Network

    Pawel Guzowski; Luke Barnes; Justin Evans; Georgia Karagiorgi; Nathan McCabe; Stefan Soldner-Rembold

    2015-06-11

    We present a framework to combine data from the latest neutrinoless double-beta decay experiments for multiple isotopes and derive a limit on the effective neutrino mass using the experimental energy distributions. The combined limits on the effective mass range between 130-310 meV, where the spread is due to different model calculations of nuclear matrix elements (NMEs). The statistical consistency (p values) between this result and the signal observation claimed by the Heidelberg-Moscow experiment is derived. The limits on the effective mass are also evaluated in a (3+1) sterile neutrino model, assuming all neutrinos are Majorana particles.

  1. A Combined Limit on the Neutrino Mass from Neutrinoless Double-Beta Decay and Constraints on Sterile Majorana Neutrinos

    E-print Network

    Guzowski, Pawel; Evans, Justin; Karagiorgi, Georgia; McCabe, Nathan; Soldner-Rembold, Stefan

    2015-01-01

    We present a framework to combine data from the latest neutrinoless double-beta decay experiments for multiple isotopes and derive a limit on the effective neutrino mass using the experimental energy distributions. The combined limits on the effective mass range between 130-310 meV, where the spread is due to different model calculations of nuclear matrix elements (NMEs). The statistical consistency (p values) between this result and the signal observation claimed by the Heidelberg-Moscow experiment is derived. The limits on the effective mass are also evaluated in a (3+1) sterile neutrino model, assuming all neutrinos are Majorana particles.

  2. The quest for neutrinoless double beta decay: Pseudo-Dirac, Majorana and sterile neutrinos

    E-print Network

    A. Meroni; E. Peinado

    2014-11-09

    In this paper we analyze the neutrinoless double beta decay predictions in some scenarios with admixture of pseudo-Dirac and Majorana neutrinos in the 3 and 3+1 neutrino frameworks. We found that some of the cases can be falsifiable in near-term and future generations of neutrinoless double beta decay experiments even for the normal neutrino mass hierarchy. In the 3+1 framework we consider the sterile neutrino with a mass of the order of 1 eV. The complementarity between cosmological constraints and the future sensitivity for the next generations of the neutrinoless double beta decay searches is exploited.

  3. Magnetic moment of the majorana neutrino in the left-right symmetric model

    SciTech Connect

    Boyarkin, O. M., E-mail: oboyarkin@tut.by; Boyarkina, G. G. [Maxim Tank Belarusian State Pedagogical University (Belarus)] [Maxim Tank Belarusian State Pedagogical University (Belarus)

    2013-04-15

    Corrections to the neutrino magnetic dipole moment from the singly charged Higgs bosons h{sup ({+-})} and {delta}-tilde{sup (}{+-}) were calculated within the left-right symmetric model involving Majorana neutrinos. It is shown that, if the h{sup ({+-})} and {delta}-tilde{sup (}{+-}) bosons lie at the electroweak scale, the contributions from Higgs sector are commensurate with the contribution of charged gauge bosons or may even exceed it. The behavior of the neutrino flux inmatter and in amagnetic field was studied. It was found that resonance transitions between light and heavy neutrinos are forbidden.

  4. Fermion Masses from Six Dimensions and Implications for Majorana Neutrinos

    E-print Network

    J-M Frère; M Libanov; S Mollet; S Troitsky

    2014-09-29

    In these notes, we review the main results of our approach to fermion masses. The marge mass ratios between fermions, confronted with a unique breaking mechanism leading to vector bosons masses, led us to consider the possibility that they result from the overlap of fermion wave functions. Such overlaps vary indeed very strongly if the observed fermion families in 4 dimensions originate in a single family in 6 dimensions, through localized wave functions. This framework leads in a natural way to large mass ratios and small mixing angles between quarks. What came as a surprise is that if we impose that neutrinos behave as 2-component ("Majorana") particles in 4D, a completely different situation is obtained for them. Instead of diagonal mass matrices, anti-diagonal ones emerge and lead to a generic prediction of combined inverted hierarchy, large mixing angles in the leptonic sector, and a suppression of neutrinoless-double beta decay placing it at the lower limit of the inverted hierarchy branch, a challenging situation for on-going and planned experiments. Our approach predicted the size of the $\\theta_{13}$ mixing angle before its actual measurement. Possible signals at colliders are only briefly evoked.

  5. Neutrino physics

    E-print Network

    E. Kh. Akhmedov

    2000-01-31

    In the present lectures the following topics are considered: general properties of neutrinos, neutrino mass phenomenology (Dirac and Majorana masses), neutrino masses in the simplest extensions of the standard model (including the seesaw mechanism), neutrino oscillations in vacuum, neutrino oscillations in matter (the MSW effect) in 2- and 3-flavour schemes, implications of CP, T and CPT symmetries for neutrino oscillations, double beta decay, solar neutrino oscillations and the solar neutrino problem, and atmospheric neutrinos. We also give a short overview of the results of the accelerator and reactor neutrino experiments and of future projects. Finally, we discuss how the available experimental data on neutrino masses and lepton mixing can be summarized in the phenomenologically allowed forms of the neutrino mass matrix.

  6. Geometry of the effective Majorana neutrino mass in the 0??? decay

    NASA Astrophysics Data System (ADS)

    Xing, Zhi-zhong; Zhou, Ye-Ling

    2015-01-01

    The neutrinoless double-beta (0???) decay is a unique process used to identify the Majorana nature of massive neutrinos, and its rate depends on the size of the effective Majorana neutrino mass ee. We put forward a novel ‘coupling-rod’ diagram to describe ee in the complex plane, by which the effects of the neutrino mass ordering and CP-violating phases on ee are intuitively understood. We show that this geometric language allows us to easily obtain the maximum and minimum of |ee|. It remains usable even if there is a kind of new physics contributing to ee, and it can also be extended to describe the effective Majorana masses e?, e?, ?? and ?? which may appear in some other lepton-number violating processes.

  7. The Majorana Zero-Neutrino Double-Beta Decay Experiment White Paper

    SciTech Connect

    Gaitskell, R.; Barabash, A.; Konovalov, S.; Stekhanov, V.; Umatov,, V.; Brudanin, V.; Egorov, S.; Webb, J.; Miley, Harry S.; Aalseth, Craig E.; Anderson, Dale N.; Bowyer, Ted W.; Brodzinski, Ronald L.; Jordan, David B.; Kouzes, Richard T.; Smith, Leon E.; Thompson, Robert C.; Warner, Ray A.; Tornow, W.; Young, A.; Collar, J. I.; Avignone, Frank T.; Palms, John M.; Doe, P. J.; Elliott, Steven R.; Kazkaz, K.; Robertson, Hamish; Wilkerson, John

    2002-03-07

    The goal of the Majorana Experiment is to determine the effective Majorana masss of the eletron neutrino. Detection of the neutrino mass implied by oscillation results in within our grasp. This exciting physics goal is best pursued using double-beta decay of germanium because of the historical and emerging advances in eliminating competing signals from radioactive backgrounds. The Majorana Experiment will consist of a large mass of 76Ge in the form of high-resolution detectors deep underground, searching for a sharp peak at the BB endpoint. We present here an overview of the entire project in order to help put in perspective the scope, the level and technial risk, and the readiness of the Collaboration to begin the undertaking.

  8. Search for Majorana neutrinos with the first two years of EXO-200 data.

    PubMed

    2014-06-12

    Many extensions of the standard model of particle physics suggest that neutrinos should be Majorana-type fermions-that is, that neutrinos are their own anti-particles-but this assumption is difficult to confirm. Observation of neutrinoless double-? decay (0???), a spontaneous transition that may occur in several candidate nuclei, would verify the Majorana nature of the neutrino and constrain the absolute scale of the neutrino mass spectrum. Recent searches carried out with (76)Ge (the GERDA experiment) and (136)Xe (the KamLAND-Zen and EXO (Enriched Xenon Observatory)-200 experiments) have established the lifetime of this decay to be longer than 10(25)?years, corresponding to a limit on the neutrino mass of 0.2-0.4?electronvolts. Here we report new results from EXO-200 based on a large (136)Xe exposure that represents an almost fourfold increase from our earlier published data sets. We have improved the detector resolution and revised the data analysis. The half-life sensitivity we obtain is 1.9?×?10(25)?years, an improvement by a factor of 2.7 on previous EXO-200 results. We find no statistically significant evidence for 0??? decay and set a half-life limit of 1.1?×?10(25)?years at the 90 per cent confidence level. The high sensitivity holds promise for further running of the EXO-200 detector and future 0??? decay searches with an improved Xe-based experiment, nEXO. PMID:24896189

  9. Search for Majorana neutrinos with the first two years of EXO-200 data

    NASA Astrophysics Data System (ADS)

    The Exo-200 Collaboration; Albert, J. B.; Auty, D. J.; Barbeau, P. S.; Beauchamp, E.; Beck, D.; Belov, V.; Benitez-Medina, C.; Bonatt, J.; Breidenbach, M.; Brunner, T.; Burenkov, A.; Cao, G. F.; Chambers, C.; Chaves, J.; Cleveland, B.; Coon, M.; Craycraft, A.; Daniels, T.; Danilov, M.; Daugherty, S. J.; Davis, C. G.; Davis, J.; Devoe, R.; Delaquis, S.; Didberidze, T.; Dolgolenko, A.; Dolinski, M. J.; Dunford, M.; Fairbank, W., Jr.; Farine, J.; Feldmeier, W.; Fierlinger, P.; Fudenberg, D.; Giroux, G.; Gornea, R.; Graham, K.; Gratta, G.; Hall, C.; Herrin, S.; Hughes, M.; Jewell, M. J.; Jiang, X. S.; Johnson, A.; Johnson, T. N.; Johnston, S.; Karelin, A.; Kaufman, L. J.; Killick, R.; Koffas, T.; Kravitz, S.; Kuchenkov, A.; Kumar, K. S.; Leonard, D. S.; Leonard, F.; Licciardi, C.; Lin, Y. H.; MacLellan, R.; Marino, M. G.; Mong, B.; Moore, D.; Nelson, R.; Odian, A.; Ostrovskiy, I.; Ouellet, C.; Piepke, A.; Pocar, A.; Prescott, C. Y.; Rivas, A.; Rowson, P. C.; Rozo, M. P.; Russell, J. J.; Schubert, A.; Sinclair, D.; Slutsky, S.; Smith, E.; Stekhanov, V.; Tarka, M.; Tolba, T.; Tosi, D.; Twelker, K.; Vogel, P.; Vuilleumier, J.-L.; Waite, A.; Walton, J.; Walton, T.; Weber, M.; Wen, L. J.; Wichoski, U.; Wright, J. D.; Yang, L.; Yen, Y.-R.; Ya. Zeldovich, O.; Zhao, Y. B.

    2014-06-01

    Many extensions of the standard model of particle physics suggest that neutrinos should be Majorana-type fermions--that is, that neutrinos are their own anti-particles--but this assumption is difficult to confirm. Observation of neutrinoless double-? decay (0???), a spontaneous transition that may occur in several candidate nuclei, would verify the Majorana nature of the neutrino and constrain the absolute scale of the neutrino mass spectrum. Recent searches carried out with 76Ge (the GERDA experiment) and 136Xe (the KamLAND-Zen and EXO (Enriched Xenon Observatory)-200 experiments) have established the lifetime of this decay to be longer than 1025 years, corresponding to a limit on the neutrino mass of 0.2-0.4 electronvolts. Here we report new results from EXO-200 based on a large 136Xe exposure that represents an almost fourfold increase from our earlier published data sets. We have improved the detector resolution and revised the data analysis. The half-life sensitivity we obtain is 1.9 × 1025 years, an improvement by a factor of 2.7 on previous EXO-200 results. We find no statistically significant evidence for 0??? decay and set a half-life limit of 1.1 × 1025 years at the 90 per cent confidence level. The high sensitivity holds promise for further running of the EXO-200 detector and future 0??? decay searches with an improved Xe-based experiment, nEXO.

  10. Majorana neutrinos, neutrino mass spectrum, and the ||{approx}10{sup -3} eV frontier in neutrinoless double beta decay

    SciTech Connect

    Pascoli, S.; Petcov, S. T. [IPPP, Department of Physics, Durham University, Durham, DH1 3LE (United Kingdom); Scuola Internazionale Superiore di Studi Avanzati, I-34014 Trieste (Italy) and Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, I-34014 Trieste (Italy)

    2008-06-01

    If future neutrino oscillation experiments show that the neutrino mass spectrum is with normal ordering, m{sub 1}Majorana mass || > or approx. 10{sup -2} eV give negative results, the next frontier in the quest for ({beta}{beta}){sub 0{nu}}-decay will correspond to ||{approx}10{sup -3} eV. By assuming that massive neutrinos are Majorana particles and their exchange is the dominant mechanism generating ({beta}{beta}){sub 0{nu}}-decay, we analyze the conditions under which ||, in the case of three-neutrino mixing and a neutrino mass spectrum with normal ordering, would satisfy ||{>=}0.001 eV. We consider the specific cases of (i) a normal hierarchical neutrino mass spectrum, (ii) a relatively small value of the CHOOZ angle {theta}{sub 13}, as well as (iii) the general case of a spectrum with normal ordering, a partial hierarchy, and a value of {theta}{sub 13} close to the existing upper limit. We study the ranges of the lightest neutrino mass m{sub 1} and/or of sin{sup 2}{theta}{sub 13} for which ||{>=}0.001 eV and discuss the phenomenological implications of such scenarios. We provide also an estimate of || when the three-neutrino masses and the neutrino mixing originate from a neutrino mass term of the Majorana type for the (left-handed) flavor neutrinos and {sub j}{sup 3}m{sub j}U{sub ej}{sup 2}=0, but there does not exist a symmetry which forbids the ({beta}{beta}){sub 0{nu}}-decay.

  11. Testing the minimal $S_4$ model of neutrinos with the Dirac and Majorana phases

    E-print Network

    Shimizu, Yusuke

    2015-01-01

    We propose two new simple lepton flavor models in the framework of the $S_4$ flavor symmetry. The neutrino mass matrices, which are given by two complex parameters, lead to the inverted mass hierarchy. The charged lepton mass matrix has the 1-2 lepton flavor mixing, which gives the non-vanishing reactor angle $\\theta_{13}$. These models predict the Dirac phase and the Majorana phases, which are testable in the future experiments. The predicted magnitudes of the effective neutrino mass for the neutrino-less double beta decay are in the regions as $32~\\text{meV}\\lesssim |m_{ee}|\\lesssim 49~\\text{meV}$ and $34~\\text{meV}\\lesssim |m_{ee}|\\lesssim 59~\\text{meV}$, respectively. These values are close to the expected reaches of the coming experiments. The total sum of the neutrino masses are predicted in both models as $0.0952~\\text{eV}\\lesssim \\sum m_i\\lesssim 0.101~\\text{eV}$ and $0.150~\\text{eV}\\lesssim \\sum m_i\\lesssim 0.160~\\text{eV}$, respectively.

  12. Hybrid textures of Majorana neutrino mass matrix and current experimental tests

    NASA Astrophysics Data System (ADS)

    Liu, Ji-Yuan; Zhou, Shun

    2013-05-01

    Motivated by recent measurements of a relatively large ?13 in the Daya Bay and RENO reactor neutrino experiments, we carry out a systematic analysis of the hybrid textures of Majorana neutrino mass matrix M?, which contain one texture zero and two equal nonzero matrix elements. We show that three neutrino masses (m1,m2,m3) and three leptonic CP-violating phases (?,?,?) can fully be determined from two neutrino mass-squared differences (?m2,?m2) and three flavor mixing angles (?12,?23,?13). Out of sixty logically possible patterns of M?, thirty-nine are found to be compatible with current experimental data at the 3? level. We demonstrate that the texture zero of M? is stable against one-loop quantum corrections, while the equality between two independent elements not. Phenomenological implications of M? for the neutrinoless double-beta decay and leptonic CP violation are discussed, and a realization of the texture zero and equality by means of discrete flavor symmetries is illustrated.

  13. Baryon Number Violation via Majorana Neutrinos in the Early Universe, at the LHC, and Deep Underground

    E-print Network

    Hooman Davoudiasl; Yue Zhang

    2015-05-07

    We propose and investigate a novel, minimal, and experimentally testable framework for baryogenesis, dubbed dexiogenesis, using baryon number violating effective interactions of right-handed Majorana neutrinos responsible for the seesaw mechanism. The distinct LHC signature of our framework is same-sign top quark final states, possibly originating from displaced vertices. The region of parameters relevant for LHC phenomenology can also yield concomitant signals in nucleon decay experiments. We provide a simple ultraviolet origin for our effective operators, by adding a color-triplet scalar, which could ultimately arise from a grand unified theory.

  14. Hadron Production of Majorana Neutrinos at Vlhc Energies

    NASA Astrophysics Data System (ADS)

    de Almeida, F. M. L.; Coutinho, Y. A.; Simões, J. A. Martins; Do Vale, M. A. B.

    2003-10-01

    The Very Large Hadron Collider (VLHC) is being proposed as a 50+50 TeV hadron collider to extend the energy frontier beyond the LHC. Since 1998-1999 the option of a ep collider operating with the 3 TeV proton booster has been considered. This design uses a 80 GeV electron beam to produce ep collisions with a luminosity of 2600 pb-1/yr with a center of mass energy of 1TeV. We study the discovery potential of this proposed ep collider for detecting new neutral heavy Majorana leptons suggested by different extensions of the Standard Model, using the channel e-p ? e+ + jets.

  15. Heavy Majorana Neutrinos from $W\\gamma$ Fusion at Hadron Colliders

    E-print Network

    Alva, Daniel; Ruiz, Richard

    2014-01-01

    Vector boson fusion processes become increasingly more important at higher collider energies and for probing larger mass scales due to collinear logarithmic enhancements of the cross section. In this context, we revisit the production of a hypothetic heavy Majorana neutrino $(N)$ at hadron colliders. Particular attention is paid to the fusion process $W\\gamma \\rightarrow N\\ell^{\\pm}$. We systematically categorize the contributions from an initial state photon in the elastic, inelastic, and deeply inelastic channels. Comparing with the leading channel via the Drell-Yan production $q \\bar{q}'\\rightarrow W^{*}\\rightarrow N\\ell^{\\pm}$ at NNLO in QCD, we find that the $W\\gamma$ fusion process becomes relatively more important at higher scales, surpassing the DY mechanism at $m_{N} \\sim 1 \\text{TeV} \\ (770 \\text{GeV})$ at the 14 TeV LHC (100 TeV VLHC). We investigate the inclusive heavy Majorana neutrino signal, including QCD corrections, and quantify the Standard Model backgrounds at future hadron colliders. We co...

  16. Probing Majorana neutrinos in rare K and D, D{sub s}, B, B{sub c} meson decays

    SciTech Connect

    Cvetic, G.; Dib, Claudio [Centro Cientifico y Tecnologico de Valparaiso and Department of Physics, Universidad Tecnica Federico Santa Maria, Valparaiso (Chile); Kang, Sin Kyu [School of Liberal Arts, Seoul National University of Technology, Seoul 121-742 (Korea, Republic of); Kim, C. S. [Department of Physics and IPAP, Yonsei University, Seoul 120-749 (Korea, Republic of)

    2010-09-01

    We study lepton number violating decays of charged K, D, D{sub s}, B, and B{sub c} mesons of the form M{sup +}{yields}M{sup '-}l{sup +}l{sup +}, induced by the existence of Majorana neutrinos. These processes provide information complementary to neutrinoless double nuclear beta decays, and are sensitive to neutrino masses and lepton mixing. We explore neutrino mass ranges m{sub N} from below 1 eV to several hundred GeV. We find that in many cases the branching ratios are prohibitively small, however in the intermediate range m{sub {pi}<}m{sub N}neutrino masses, the branching ratios can be at the reach of high luminosity experiments like those at the LHC-b and future super flavor factories, and can provide bounds on the lepton mixing parameters.

  17. Connecting Dirac and Majorana neutrino mass matrices in the minimal left-right symmetric model.

    PubMed

    Nemevšek, Miha; Senjanovi?, Goran; Tello, Vladimir

    2013-04-12

    Probing the origin of neutrino mass by disentangling the seesaw mechanism is one of the central issues of particle physics. We address it in the minimal left-right symmetric model and show how the knowledge of light and heavy neutrino masses and mixings suffices to determine their Dirac Yukawa couplings. This in turn allows one to make predictions for a number of high and low energy phenomena, such as decays of heavy neutrinos, neutrinoless double beta decay, electric dipole moments of charged leptons, and neutrino transition moments. We also discuss a way of reconstructing the neutrino Dirac Yukawa couplings at colliders such as the LHC. PMID:25167249

  18. Are neutrinos their own antiparticles?

    NASA Astrophysics Data System (ADS)

    Kayser, Boris

    2009-06-01

    We explain the relationship between Majorana neutrinos, which are their own antiparticles, and Majorana neutrino masses. We point out that Majorana masses would make the neutrinos very distinctive particles, and explain why many theorists strongly suspect that neutrinos do have Majorana masses. The promising approach to confirming this suspicion is to seek neutrinoless double beta decay. We introduce a toy model that illustrates why this decay requires nonzero neutrino masses, even when there are both right-handed and left-handed weak currents.

  19. Neutrino electromagnetic properties

    SciTech Connect

    Giunti, C., E-mail: giunti@to.infn.i [University of Turin, INFN, Section of Turin (Italy); Studenikin, A., E-mail: studenik@srd.sinp.msu.r [Moscow State University, Department of Theoretical Physics (Russian Federation)

    2009-12-15

    The main goal of the paper is to give a short review on neutrino electromagnetic properties. In the introductory part of the paper a summary on what we really know about neutrinos is given: we discuss the basics of neutrino mass and mixing as well as the phenomenology of neutrino oscillations. This is important for the following discussion on neutrino electromagnetic properties that starts with a derivation of the neutrino electromagnetic vertex function in the most general form, that follows from the requirement of Lorentz invariance, for both the Dirac and Majorana cases. Then, the problem of the neutrino form factor definition and calculation within gauge models is considered. In particular, we discuss the neutrino electric charge form factor and charge radius, dipole magnetic and electric and anapole form factors. Available experimental constraints on neutrino electromagnetic properties are also discussed, and the recently obtained experimental limits on neutrino magnetic moments are reviewed. The most important neutrino electromagnetic processes involving a direct neutrino coupling with photons (such as neutrino radiative decay, neutrino Cherenkov radiation, spin light of neutrino and plasmon decay into neutrino-antineutrino pair in media) and neutrino resonant spin-flavor precession in a magnetic field are discussed at the end of the paper.

  20. Nuclear matrix elements for 0 ? ? ? decays with light or heavy Majorana-neutrino exchange

    NASA Astrophysics Data System (ADS)

    Hyvärinen, Juhani; Suhonen, Jouni

    2015-02-01

    We compute the nuclear matrix elements (NMEs) corresponding to the neutrinoless double beta (0 ? ? ? ) decays of nuclei which attract current experimental interest. We concentrate on ground-state-to-ground-state decay transitions mediated by light (l-NMEs) or heavy (h-NMEs) Majorana neutrinos. The computations are done in realistic single-particle model spaces using the proton-neutron quasiparticle random-phase approximation (pnQRPA) with two-nucleon interactions based on the Bonn one-boson-exchange G matrix. Both the l-NMEs and the h-NMEs include the appropriate short-range correlations, nucleon form factors, and higher-order nucleonic weak currents. In addition, both types of NMEs are corrected for the isospin symmetry by the recently proposed method in which the particle-particle proton-neutron interaction parameter (gpp) is decomposed into isoscalar (gppT =0) and isovector (gppT =1) parts. A detailed analysis of the l-NMEs and the h-NMEs is performed to benchmark our computer code and to compare with other recent calculations which produce h-NMEs that are in tension with each other.

  1. Neutrino Physics

    NASA Astrophysics Data System (ADS)

    Bergström, L.; Hulth, P. O.; Botner, O.; Carlson, P.; Ohlsson, T.

    2006-03-01

    J. N. Bahcall (1934-2005) -- Preface -- List of participants -- Committees -- Nobel symposium on neutrino physics - program -- The history of neutrino oscillations / S. M. Bilenky -- Super-Kamiokande results on neutrino oscillations / Y. Suzuki -- Sudbury neutrino observatory results / A. B. McDonald -- Results from KamLAND reactor neutrino detection / A. Suzuki -- New opportunities for surprise / J. Conrad -- Solar models and solar neutrinos / J. N. Bahcall -- Atmospheric neutrino fluxes / T. K. Gaisser -- The MSW effect and matter effects in neutrino oscillations / A. Yu. Smirnov -- Three-flavour effects and CP- and T-violation in neutrino oscillations / E. Kh. Akhmedov -- Global analysis of neutrino data / M. C. Gonzalez-Garcia -- Future precision neutrino oscillation experiments and theoretical implications / M. Lindner -- Experimental prospects of neutrinoless double beta decay / E. Fiorini -- Theoretical prospects of neutrinoless double beta decay / S. T. Petcov -- Supernova neutrino oscillations / G. G. Raffelt -- High-energy neutrino astronomy / F. Halzen -- Neutrino astrophysics in the cold: Amanda, Baikal and IceCube / C. Spiering -- Status of radio and acoustic detection of ultra-high energy cosmic neutrinos and a proposal on reporting results / D. Saltzberg -- Detection of neutrino-induced air showers / A. A. Watson -- Prospect for relic neutrino searches / G. B. Gelmini -- Leptogenesis in the early universe / T. Yanagida -- Neutrinos and big bang nucleosynthesis / G. Steigman -- Extra galactic sources of high energy neutrinos / E. Waxman -- Cosmological neutrino bounds for non-cosmologists / M. Tegmark -- Neutrino intrinsic properties: the neutrino-antineutrino relation / B. Kayser -- NuTeV and neutrino properties / M. H. Shaevitz -- Absolute masses of neutrinos - experimental results and future possibilities / C. Weinheimer -- Flavor theories and neutrino masses / P. Ramond -- Neutrino mass models and leptogenesis / S. F. King -- Neutrino mass and grand unification / R. N. Mohapatra.

  2. Cosmic Neutrinos

    SciTech Connect

    Quigg, Chris; /Fermilab /CERN

    2008-02-01

    I recall the place of neutrinos in the electroweak theory and summarize what we know about neutrino mass and flavor change. I next review the essential characteristics expected for relic neutrinos and survey what we can say about the neutrino contribution to the dark matter of the Universe. Then I discuss the standard-model interactions of ultrahigh-energy neutrinos, paying attention to the consequences of neutrino oscillations, and illustrate a few topics of interest to neutrino observatories. I conclude with short comments on the remote possibility of detecting relic neutrinos through annihilations of ultrahigh-energy neutrinos at the Z resonance.

  3. Search for heavy Majorana neutrinos in mu+/- mu+/- + jets events in proton-proton collisions at sqrt(s) = 8 TeV

    E-print Network

    CMS Collaboration

    2015-01-22

    A search is performed for heavy Majorana neutrinos (N) using an event signature defined by two muons of the same charge and two jets (mu+/- mu+/- jj). The data correspond to an integrated luminosity of 19.7 inverse femtobarns of proton-proton collisions at a center-of-mass energy of 8 TeV, collected with the CMS detector at the CERN LHC. No excess of events is observed beyond the expected standard model background and upper limits are set on abs(V[mu,N])^2 as a function of Majorana neutrino mass m[N] for masses in the range of 40-500 GeV, where V[mu,N] is the mixing element of the heavy neutrino with the standard model muon neutrino. The limits obtained are abs(V[mu,N])^2 500 GeV. These results extend considerably the regions excluded by previous direct searches.

  4. Neutrino Parameter Space for a Vanishing $ee$ Element in the Neutrino Mass Matrix

    E-print Network

    S. Dev; Sanjeev Kumar

    2007-05-24

    The consequences of a texture zero at the $ee$ entry of neutrino mass matrix in the flavor basis, which also implies a vanishing effective Majorana mass for neutrinoless double beta decay, have been studied for Majorana neutrinos. The neutrino parameter space under this condition has been constrained in the light of all available neutrino data including the CHOOZ bound on $s_{13}^{2}$.

  5. Neutrino oscillations, neutrino masses and supersymmetry

    NASA Astrophysics Data System (ADS)

    Faessler, A.

    2002-07-01

    The neutrino mass matrix is constraint considering in a three-generation scenario, which includes or excludes LSND and considers the atmospheric neutrinos of Super-Kamiokande and the solar neutrino experiments. In this way one is able to construct the neutrino mass matrix, up to a mass scale and up to the Majorana neutrino CP eigenvalues. By using the expectation value of the electron neutrino mass obtained in the neutrinoless double beta decay, one can derive an upper limit of 2.53 [eV] for the sum of the masses of the three neutrinos. In a second part we use the R violating minimal supersymmetric model ( R-MSSM) to construct the neutrino mass matrix. The contributions on the tree level yield by mixing with the neutralinos (photino, zino, higgsino 1 and higgsino 2) a separable 3 · 3 mass matrix, which has two mass eigenvalues, which are zero and a third eigenvalue different from zero. This yields a hierachichal structure of two neutrinos with small masses and a third neutrino with a larger mass. If one includes the loop diagrams of quarks and SUSY quarks and of leptons and SUSY leptons one obtains for the three neutrinos a sum of tree separable matrices. Such a separable mass matrix of rank 3 has 9 independent parameters. One can fit five parameters from the neutrino oscillations: the three mixing angles of the matrix transforming the neutrinos from the mass eigenstates to the weak eigenstates and the two differences of the squared masses. One therefore has to reduce the nine free parameters of the mass matrix in the R-MSSM from nine to five. This is possible imposing a constraint on the cubic couplings employing an additional U(1) flavour symmetry. This approach has been very successful in studying the Yukawa couplings to fix the masses of the quarks and the non-neutrino leptons. In this way it is possible to reduce the R-parity violating coupling constants of the the R-MSSM from six to one. This reduces the free parameters of the neutrino mass matrix obtained in the SUSY model to four. We find in a three-family mixing scheme an averaged Majorana neutrino mass, which in principle can be obtained from the neutrinoless double beta decay, of | < m > | = 0.009 to 0.045[ eV]. These predictions can perhaps be tested by the next generation of neutrinoless double beta decay experiments.

  6. Neutrino oscillations

    SciTech Connect

    Simkovic, Fedor [Faculty of Mathematics, Physics and Informatics, Comenius University, Mlynska dolina, SK-84248 Bratislava (Slovakia)

    2007-11-26

    The field of neutrino oscillations is introduced. The basic elements of the theory of neutrino oscillations in vacuum and matter are presented. The history, current status of neutrino oscillations as well as the prospects for the next generation of neutrino experiments are briefly reviewed.

  7. Neutrino mixings and leptonic CP violation from CKM matrix and Majorana phases

    Microsoft Academic Search

    Sanjib Kumar Agarwalla; M. K. Parida; R. N. Mohapatra; G. Rajasekaran

    2007-01-01

    The high scale mixing unification hypothesis recently proposed by three of us (R. N. M., M. K. P. and G. R.) states that if at the seesaw scale the quark and lepton mixing matrices are equal, then for quasidegenerate neutrinos radiative corrections can lead to large solar and atmospheric mixings and small reactor angle at the weak scale in agreement

  8. The contribution of light Majorana neutrinos to neutrinoless double beta decay and cosmology

    E-print Network

    Dell'Oro, Stefano; Viel, Matteo; Vissani, Francesco

    2015-01-01

    Cosmology is making impressive progress and it is producing stringent bounds on the sum of the neutrino masses {\\Sigma}, a parameter of great importance for the current laboratory experiments. In this letter, we exploit the potential relevance of the analysis of Palanque-Delabrouille et al. [JCAP 1502, 045 (2015)] to the neutrinoless double beta decay (0\

  9. Neutrino physics

    SciTech Connect

    Harris, Deborah A.; /Fermilab

    2008-09-01

    The field of neutrino physics has expanded greatly in recent years with the discovery that neutrinos change flavor and therefore have mass. Although there are many neutrino physics results since the last DIS workshop, these proceedings concentrate on recent neutrino physics results that either add to or depend on the understanding of Deep Inelastic Scattering. They also describe the short and longer term future of neutrino DIS experiments.

  10. Cosmic Neutrino Flavor Democracy and Unitarity Violation at Neutrino Telescopes

    E-print Network

    Xing, Zhi-zhong

    2008-01-01

    Provided ultrahigh-energy cosmic neutrinos are produced from the decays of charged pions arising from proton-proton and (or) proton-gamma collisions, their flavor ratios at a neutrino telescope will be \\phi^T_e : \\phi^T_\\mu : \\phi^T_\\tau \\approx 1 : 1 : 1. We show that the exact flavor democracy can occur if the unitary neutrino mixing matrix satisfies either \\theta_13 = 0 and \\theta_{23} = \\pi/4 (CP invariance) or \\delta= \\pm \\pi/2 and \\theta_{23} = \\pi/4 (CP violation) in the standard parametrization. Allowing for slight deviations from either condition, we calculate the corresponding neutrino flavor distribution at neutrino telescopes. If the neutrino mixing matrix is non-unitary, as expected in a class of seesaw models with TeV-scale Majorana neutrinos, we demonstrate that the effect of unitarity violation on the flavor democracy of cosmic neutrinos at neutrino telescopes can be as large as several percent.

  11. Neutrino mixings and leptonic CP violation from CKM matrix and Majorana phases

    Microsoft Academic Search

    Sanjib Kumar Agarwalla; M. K. Parida; R. N. Mohapatra; G. Rajasekaran

    2007-01-01

    The high scale mixing unification hypothesis recently proposed by three of us\\u000a(R. N. M., M. K. P. and G. R.) states that if at the seesaw scale, the quark\\u000aand lepton mixing matrices are equal then for quasi-degenerate neutrinos,\\u000aradiative corrections can lead to large solar and atmospheric mixings and small\\u000areactor angle at the weak scale in agreement

  12. Direct neutrino mass measurements

    NASA Astrophysics Data System (ADS)

    Thümmler, T.

    2011-07-01

    The determination of the neutrino rest mass plays an important role at the intersections of cosmology, particle physics and astroparticle physics. This topic is currently being addressed by two complementary approaches in laboratory experiments. Neutrinoless double beta decay experiments probe whether neutrinos are Majorana particles and determine an effective neutrino mass value. Single beta decay experiments such as KATRIN and MARE investigate the spectral shape of ?-decay electrons close to their kinematic endpoint in order to determine the neutrino rest mass with a model-independent method. Owing to neutrino flavour mixing, the neutrino mass parameter appears as an average of all neutrino mass eigenstates contributing to the electron neutrino. The KArlsruhe TRItium Neutrino experiment (KATRIN) is currently the experiment in the most advanced status of commissioning. Applying an ultra-luminous molecular windowless gaseous tritium source and an integrating high-resolution spectrometer of MAC-E filter type, it allows ?-spectroscopy close to the T 2 end-point with unprecedented precision and will reach a sensitivity of 200 meV/ c 2 (90% C.L.) on the neutrino rest mass.

  13. Neutrino masses and Neutrinoless Double Beta Decay: Status and expectations

    Microsoft Academic Search

    Oliviero Cremonesi

    2010-01-01

    Two most outstanding questions are puzzling the world of neutrino Physics: the possible Majorana nature of neutrinos and their absolute mass scale. Direct neutrino mass measurements and neutrinoless double beta decay (0nuDBD) are the present strategy to solve the puzzle. Neutrinoless double beta decay violates lepton number by two units and can occurr only if neutrinos are massive Majorana particles.

  14. Neutrino unification.

    PubMed

    Chankowski, P H; Ioannisian, A N; Pokorski, S; Valle, J W

    2001-04-16

    Present neutrino data are consistent with neutrino masses arising from a common seed at some "neutrino unification" scale M(X). Such a simple theoretical ansatz naturally leads to quasidegenerate neutrinos that could lie in the electron-volt range with neutrino mass splittings induced by renormalization effects associated with supersymmetric thresholds. In such a scheme the leptonic analog of the Cabibbo angle straight theta(middle dot in circle) describing solar neutrino oscillations is nearly maximal. Its exact value is correlated with the smallness of straight theta(reactor). The two leading mass-eigenstate neutrinos present in nu(e) form a pseudo-Dirac neutrino, avoiding conflict with neutrinoless double beta decay. PMID:11328005

  15. Neutrino physics

    Microsoft Academic Search

    F. Dydak

    2004-01-01

    Neutrino physics has a glorious past at CERN. It entered the scene with the groundbreaking discovery of neutral currents in 1973, and made essential contributions, until 1984, toward establishing the rule of the Standard Model. Nature's choice of neutrino oscillation parameters was not favourable to CERN experiments carried out in the subsequent phase, until 1998. However, the new neutrino beam

  16. Neutrino Telescopes

    SciTech Connect

    Hernandez-Rey, Juan Jose [IFIC - Instituto de Fisica Corpuscular, C.S.I.C. - Universitat de Valencia, E-46071, Valencia (Spain)

    2006-11-28

    We review the present status of high energy neutrino astronomy. The advantages of neutrinos as extra-terrestrial messengers are recalled and their possible extra-terrestrial sources examined. We review as well the status of present and future neutrino telescopes and summarize the results obtained so far in this field.

  17. Neutrino Radar

    E-print Network

    P. Panigrahi; U. Sarkar

    2002-09-05

    We point out that with improving our present knowledge of experimental neutrino physics it will be possible to locate nuclear powered vehicles like submarines, aircraft carriers and UFOs and detect nuclear testing. Since neutrinos cannot be shielded, it will not be possible to escape these detection. In these detectors it will also be possible to perform neutrino oscillation experiments during any nuclear testing.

  18. A New Spin on Neutrino Quantum Kinetics

    E-print Network

    Vincenzo Cirigliano; George M. Fuller; Alexey Vlasenko

    2015-05-05

    Recent studies have demonstrated that in anisotropic environments a coherent spin-flip term arises in the Quantum Kinetic Equations (QKEs) which govern the evolution of neutrino flavor and spin in hot and dense media. This term can mediate neutrino-antineutrino transformation for Majorana neutrinos and active-sterile transformation for Dirac neutrinos. We discuss the physical origin of the coherent spin-flip term and provide explicit expressions for the QKEs in a two-flavor model with spherical geometry. In this context, we demonstrate that coherent neutrino spin transformation depends on the absolute neutrino mass and Majorana phases.

  19. Neutrino mass hierarchy

    NASA Astrophysics Data System (ADS)

    Qian, X.; Vogel, P.

    2015-07-01

    The neutrino mass hierarchy, i.e., whether the ?3 neutrino mass eigenstate is heavier or lighter than the ?1 and ?2 mass eigenstates, is one of the remaining undetermined fundamental features of the neutrino Standard Model. Its determination would represent an important step in the formulation of the generalized model, and would have a profound impact on the quest of the nature of neutrinos (Dirac or Majorana) and the search for a theory of flavor. In this review, we summarize the status of experimental and theoretical work in this field and explore the future opportunities that emerge in light of the recently discovered non-zero and relatively large third neutrino mixing angle ?13.

  20. Neutrino Intrinsic Properties: The Neutrino-Antineutrino Relation

    NASA Astrophysics Data System (ADS)

    Kayser, Boris

    2005-01-01

    Are neutrinos their own antiparticles? We explain why they very well might be. Then, after highlighting the fact that, to determine experimentally whether they are or not, one must overcome the smallness of neutrino masses, we discuss the one approach that nevertheless shows great promise. Finally, we turn to the consequences of neutrinos being their own antiparticles. These consequences include unusual electromagnetic properties, and manifestly CP-violating effects from "Majorana" phases that have no quark analogues.

  1. Neutrino Intrinsic Properties:. The Neutrino-Antineutrino Relation

    NASA Astrophysics Data System (ADS)

    Kayser, Boris

    2006-03-01

    Are neutrinos their own antiparticles? We explain why they very well might be. Then, after highlighting the fact that, to determine experimentally whether they are or not, one must overcome the smallness of neutrino masses, we discuss the one approach that nevertheless shows great promise. Finally, we turn to the consequences of neutrinos being their own antiparticles. These consequences include unusual electromagnetic properties, and manifestly CP-violating effects from "Majorana" phases that have no quark analogues.

  2. Neutrino Masses at the LHC

    NASA Astrophysics Data System (ADS)

    Deppisch, Frank F.

    2015-04-01

    Neutrinoless double beta decay is the traditional tool to probe Majorana neutrino masses and lepton number violating physics in general. On the other hand, many models incorporating Majorana neutrino masses also predict new states and lepton number violating interactions at the TeV scale that can potentially be probed at the LHC. We provide a brief overview of the pertinent operators and a selection of physics models in order to highlight the interplay between neutrinoless double beta decay and LHC searches.

  3. Neutrino factory

    NASA Astrophysics Data System (ADS)

    Bogomilov, M.; Matev, R.; Tsenov, R.; Dracos, M.; Bonesini, M.; Palladino, V.; Tortora, L.; Mori, Y.; Planche, T.; Lagrange, J. B.; Kuno, Y.; Benedetto, E.; Efthymiopoulos, I.; Garoby, R.; Gilardoini, S.; Martini, M.; Wildner, E.; Prior, G.; Blondel, A.; Karadzhow, Y.; Ellis, M.; Kyberd, P.; Bayes, R.; Laing, A.; Soler, F. J. P.; Alekou, A.; Apollonio, M.; Aslaninejad, M.; Bontoiu, C.; Jenner, L. J.; Kurup, A.; Long, K.; Pasternak, J.; Zarrebini, A.; Poslimski, J.; Blackmore, V.; Cobb, J.; Tunnell, C.; Andreopoulos, C.; Bennett, J. R. J.; Brooks, S.; Caretta, O.; Davenne, T.; Densham, C.; Edgecock, T. R.; Fitton, M.; Kelliher, D.; Loveridge, P.; McFarland, A.; Machida, S.; Prior, C.; Rees, G.; Rogers, C.; Rooney, M.; Thomason, J.; Wilcox, D.; Booth, C.; Skoro, G.; Back, J. J.; Harrison, P.; Berg, J. S.; Fernow, R.; Gallardo, J. C.; Gupta, R.; Kirk, H.; Simos, N.; Stratakis, D.; Souchlas, N.; Witte, H.; Bross, A.; Geer, S.; Johnstone, C.; Makhov, N.; Neuffer, D.; Popovic, M.; Strait, J.; Striganov, S.; Morfín, J. G.; Wands, R.; Snopok, P.; Bagacz, S. A.; Morozov, V.; Roblin, Y.; Cline, D.; Ding, X.; Bromberg, C.; Hart, T.; Abrams, R. J.; Ankenbrandt, C. M.; Beard, K. B.; Cummings, M. A. C.; Flanagan, G.; Johnson, R. P.; Roberts, T. J.; Yoshikawa, C. Y.; Graves, V. B.; McDonald, K. T.; Coney, L.; Hanson, G.

    2014-12-01

    The properties of the neutrino provide a unique window on physics beyond that described by the standard model. The study of subleading effects in neutrino oscillations, and the race to discover CP-invariance violation in the lepton sector, has begun with the recent discovery that ?13>0 . The measured value of ?13 is large, emphasizing the need for a facility at which the systematic uncertainties can be reduced to the percent level. The neutrino factory, in which intense neutrino beams are produced from the decay of muons, has been shown to outperform all realistic alternatives and to be capable of making measurements of the requisite precision. Its unique discovery potential arises from the fact that only at the neutrino factory is it practical to produce high-energy electron (anti)neutrino beams of the required intensity. This paper presents the conceptual design of the neutrino factory accelerator facility developed by the European Commission Framework Programme 7 EURO ? Design Study consortium. EURO ? coordinated the European contributions to the International Design Study for the Neutrino Factory (the IDS-NF) collaboration. The EURO ? baseline accelerator facility will provide 1 021 muon decays per year from 12.6 GeV stored muon beams serving a single neutrino detector situated at a source-detector distance of between 1 500 km and 2 500 km. A suite of near detectors will allow definitive neutrino-scattering experiments to be performed.

  4. Neutrino Oscillometry

    E-print Network

    J. D. Vergados; Y. Giomataris; Yu. N. Novikov

    2010-10-21

    Neutrino oscillations are studied employing sources of low energy monoenergetic neutrinos following electron capture by the nucleus and measuring electron recoils. Since the neutrino energy is very low the oscillation length appearing in this electronic neutrino disappearance experiment can be so small that the full oscillation can take place inside the detector. Thus one may determine very accurately all the neutrino oscillation parameters. In particular one can measure or set a better limit on the unknown parameter theta13. One, however, has to pay the price that the expected counting rates are very small. Thus one needs a very intensive neutrino source and a large detector with as low as possible energy threshold and high energy and position resolution. Both spherical gaseous and cylindrical liquid detectors are studied. Different source candidates are considered

  5. Atmospheric neutrinos and discovery of neutrino oscillations.

    PubMed

    Kajita, Takaaki

    2010-01-01

    Neutrino oscillation was discovered through studies of neutrinos produced by cosmic-ray interactions in the atmosphere. These neutrinos are called atmospheric neutrinos. They are produced as decay products in hadronic showers resulting from collisions of cosmic rays with nuclei in the atmosphere. Electron-neutrinos and muon-neutrinos are produced mainly by the decay chain of charged pions to muons to electrons. Atmospheric neutrino experiments observed zenith-angle and energy dependent deficit of muon-neutrino events. Neutrino oscillations between muon-neutrinos and tau-neutrinos explain these data well. Neutrino oscillations imply that neutrinos have small but non-zero masses. The small neutrino masses have profound implications to our understanding of elementary particle physics and the Universe. This article discusses the experimental discovery of neutrino oscillations. PMID:20431258

  6. Renormalization group evolution of neutrino parameters in presence of seesaw threshold effects and Majorana phases

    NASA Astrophysics Data System (ADS)

    Gupta, Shivani; Kang, Sin Kyu; Kim, C. S.

    2015-04-01

    We examine the renormalization group evolution (RGE) for different mixing scenarios in the presence of seesaw threshold effects from high energy scale (GUT) to the low electroweak (EW) scale in the Standard Model (SM) and Minimal Supersymmetric Standard Model (MSSM). We consider four mixing scenarios namely Tri-Bimaximal Mixing, Bimaximal Mixing, Hexagonal Mixing and Golden Ratio Mixing which come from different flavor symmetries at the GUT scale. We find that the Majorana phases play an important role in the RGE running of these mixing patterns along with the seesaw threshold corrections. We present a comparative study of the RGE of all these mixing scenarios both with and without Majorana CP phases when seesaw threshold corrections are taken into consideration. We find that in the absence of these Majorana phases both the RGE running and seesaw effects may lead to ?13 < 5 ° at low energies both in the SM and MSSM. However, if the Majorana phases are incorporated into the mixing matrix the running can be enhanced both in the SM and MSSM. Even by incorporating non-zero Majorana CP phases in the SM, we do not get ?13 in its present 3? range. The current values of the two mass squared differences and mixing angles including ?13 can be produced in the MSSM case with tan ? ? = 10 and non-zero Majorana CP phases at low energy. We also calculate the order of effective Majorana mass and Jarlskog Invariant for each scenario under consideration.

  7. CP violation in neutrino oscillation and leptogenesis.

    PubMed

    Endoh, T; Kaneko, S; Kang, S K; Morozumi, T; Tanimoto, M

    2002-12-01

    We study the correlation between CP violation in neutrino oscillations and leptogenesis in the framework with two heavy Majorana neutrinos and three light neutrinos. Among three unremovable CP phases, a heavy Majorana phase contributes to leptogenesis. We show how the heavy Majorana phase contributes to Jarlskog determinant J as well as neutrinoless double beta decay by identifying a low energy CP-violating phase which signals the CP-violating phase for leptogenesis. For some specific cases of the Dirac mass term of neutrinos, a direct relation between lepton number asymmetry and J is obtained. We also study the effect coming from the phases which are not related to leptogenesis. PMID:12484996

  8. Massive neutrinos in particle physics and astrophysics

    SciTech Connect

    Rosen, S.P.

    1986-01-01

    The concepts of Majorana and Dirac neutrinos are reviewed from an operational point of view and survey the experimental search for neutrino mass. Also reviewed are the work of Mikheyev and Smirnov on the enhancement of neutrino oscillations via the mechanism of Wolfenstein matter oscillations. Results of an extensive computation of MSW effects in the sun are described. 41 refs., 6 figs.

  9. Small neutrino masses from supersymmetry breaking

    Microsoft Academic Search

    Nima Arkani-Hamed; Lawrence Hall; Hitoshi Murayama; David Smith; Neal Weiner

    2001-01-01

    An alternative to the conventional seesaw mechanism is proposed to explain the origin of small neutrino masses in supersymmetric theories. The masses and couplings of the right-handed neutrino field are suppressed by supersymmetry breaking, in a way similar to the suppression of the Higgs doublet mass mu. New mechanisms for light Majorana and Dirac neutrinos arise, depending on the degree

  10. Nonstandard neutrino-neutrino refractive effects in dense neutrino gases

    NASA Astrophysics Data System (ADS)

    Blennow, Mattias; Mirizzi, Alessandro; Serpico, Pasquale D.

    2008-12-01

    We investigate the effects of nonstandard four-fermion neutrino-neutrino interactions on the flavor evolution of dense neutrino gases. We find that in the regions where the neutrino-neutrino refractive index leads to collective flavor oscillations, the presence of new neutrino interactions can produce flavor equilibration in both normal and inverted neutrino mass hierarchy. In realistic supernova environments, these effects are significant if the nonstandard neutrino-neutrino interaction strength is comparable to the one expected in the standard case, dominating the ordinary matter potential. However, very small nonstandard neutrino-neutrino couplings are enough to trigger the usual collective neutrino flavor transformations in the inverted neutrino mass hierarchy, even if the mixing angle vanishes exactly.

  11. Neutrino mass

    SciTech Connect

    Bowles, T.J.

    1993-04-01

    Neutrinos play a dominant role in both particle physics, astrophysics, and cosmology. In the our present understanding of the strong, weak, and electromagnetic forces, the group structure of the Standard Model is SU(3){sub C} {circle_times} SU(2){sub L} {circle_times} U(I){sub EM}. In the Weinberg-Salam-Glashow Standard Electroweak Model, left-handed neutrinos sit in a doublet, while right-handed neutrinos are in a singlet, and therefore do not interact with the other known particles. Also in this model, the neutrinos are intrinsically massless. However, while the W-S-G model provides an amazingly accurate picture of our present cold Universe, It has a number of deficits. The Standard Model does not explain the origin of the group structure, It does not reduce the number of coupling constants required, nor does it offer any prediction for the physical masses of the particles. Thus, it is generally assumed that the Standard Model is but a subset of some larger gauge theory. A wide variety of Grand Unified field Theories (GUTs), Super Symmetric Models (SUSY), and Superstring models have been proposed as the model for this larger structure. In general, these models predict nonzero neutrino masses and contain mechanisms that provide for lepton-number violation. Thus, a variety of new phenomena are predicted, including finite neutrino masses and the possibility that neutrinos can oscillate from one type to another. This report looks at the possibility of detecting neutrino vat mass.

  12. Neutrino mass

    SciTech Connect

    Bowles, T.J.

    1993-01-01

    Neutrinos play a dominant role in both particle physics, astrophysics, and cosmology. In the our present understanding of the strong, weak, and electromagnetic forces, the group structure of the Standard Model is SU(3)[sub C] [circle times] SU(2)[sub L] [circle times] U(I)[sub EM]. In the Weinberg-Salam-Glashow Standard Electroweak Model, left-handed neutrinos sit in a doublet, while right-handed neutrinos are in a singlet, and therefore do not interact with the other known particles. Also in this model, the neutrinos are intrinsically massless. However, while the W-S-G model provides an amazingly accurate picture of our present cold Universe, It has a number of deficits. The Standard Model does not explain the origin of the group structure, It does not reduce the number of coupling constants required, nor does it offer any prediction for the physical masses of the particles. Thus, it is generally assumed that the Standard Model is but a subset of some larger gauge theory. A wide variety of Grand Unified field Theories (GUTs), Super Symmetric Models (SUSY), and Superstring models have been proposed as the model for this larger structure. In general, these models predict nonzero neutrino masses and contain mechanisms that provide for lepton-number violation. Thus, a variety of new phenomena are predicted, including finite neutrino masses and the possibility that neutrinos can oscillate from one type to another. This report looks at the possibility of detecting neutrino vat mass.

  13. Neutrino Telescopes

    SciTech Connect

    Carr, John [Centre de Physiques des Particules de Marseille, IN2P3/CNRS (France)

    2005-02-21

    Neutrino telescopes complement gamma ray telescopes in the observations of energetic astronomical sources as well as in searching for the dark matter. This paper gives the status of the current generation neutrino telescopes projects: Baikal, AMANDA, NESTOR, NEMO and ANTARES with particular emphasis on the ANTARES telescope in the Mediterranean Sea.

  14. Neutrino telescopes

    SciTech Connect

    Costantini, H., E-mail: costant@cppm.in2p3.fr [CPPM, Aix-Marseille Universite, CNRS/IN2P3 (France)

    2012-09-15

    Neutrino astrophysics offers a new possibility to observe our Universe: high-energy neutrinos, produced by the most energetic phenomena in our Galaxy and in the Universe, carry complementary (if not exclusive) information about the cosmos: this young discipline extends in fact the conventional astronomy beyond the usual electromagnetic probe. The weak interaction of neutrinos with matter allows them to escape from the core of astrophysical objects and in this sense they represent a complementary messenger with respect to photons. However, their detection on Earth due to the small interaction cross section requires a large target mass. The aim of this article is to review the scientific motivations of the high-energy neutrino astrophysics, the detection principles together with the description of a running apparatus, the experiment ANTARES, the performance of this detector with some results, and the presentation of other neutrino telescope projects.

  15. Seesaw mechanism and the neutrino mass matrix

    E-print Network

    E. Kh. Akhmedov

    2000-01-05

    The seesaw mechanism of neutrino mass generation is analysed under the following assumptions: (1) minimal seesaw with no Higgs triplets, (2) hierarchical Dirac masses of neutrinos, (3) large lepton mixing primarily or solely due to the mixing in the right-handed neutrino sector, and (4) unrelated Dirac and Majorana sectors of neutrino masses. It is shown that large mixing governing the dominant channel of the atmospheric neutrino oscillations can be naturally obtained and that this constrained seesaw mechanism favours the normal mass hierarchy for the light neutrinos leading to a small $U_{e3}$ entry of the lepton mixing matrix and a mass scale of the lightest right handed neutrino $M\\simeq 10^{10} - 10^{11}$ GeV. Any of the three main neutrino oscillation solutions to the solar neutrino problem can be accommodated. The inverted mass hierarchy and quasi-degeneracy of neutrinos are disfavoured in our scheme.

  16. The Gran Sasso Laboratory and Neutrinos

    SciTech Connect

    Bettini, Alessandro [University of Padua-G. Galilei Physics Department- and INFN. Via Marzolo 8 35131 Padova (Italy); Laboratorio Subterraneo de Canfranc. Canfranc, Huesca (Spain)

    2008-01-24

    After a brief survey of the experimental programme of the INFN Gran Sasso National Laboratory, I summarize the status of neutrino physics. I then focus on two frontier challenges. 1. The possible solution of the mass spectrum hierarchy problem with the observation of neutrinos from a supernova explosion; 2. The establishment of the nature of neutrinos, whether they are Dirac or Majorana particles, with neutrino-less double-beta decay.

  17. Neutrino mass textures with maximal CP violation

    SciTech Connect

    Aizawa, Ichiro; Kitabayashi, Teruyuki; Yasue, Masaki [Department of Physics, Tokai University, 1117 Kitakaname, Hiratsuka, Kanagawa 259-1292 (Japan)

    2005-09-01

    We show three types of neutrino mass textures, which give maximal CP violation as well as maximal atmospheric neutrino mixing. These textures are described by six real mass parameters: one specified by two complex flavor neutrino masses and two constrained ones and the others specified by three complex flavor neutrino masses. In each texture, we calculate mixing angles and masses, which are consistent with observed data, as well as Majorana CP phases.

  18. Pseudo-dirac neutrinos: a challenge for neutrino telescopes.

    PubMed

    Beacom, John F; Bell, Nicole F; Hooper, Dan; Learned, John G; Pakvasa, Sandip; Weiler, Thomas J

    2004-01-01

    Neutrinos may be pseudo-Dirac states, such that each generation is actually composed of two maximally mixed Majorana neutrinos separated by a tiny mass difference. The usual active neutrino oscillation phenomenology would be unaltered if the pseudo-Dirac splittings are deltam(2) less, similar 10(-12) eV(2); in addition, neutrinoless double beta decay would be highly suppressed. However, it may be possible to distinguish pseudo-Dirac from Dirac neutrinos using high-energy astrophysical neutrinos. By measuring flavor ratios as a function of L/E, mass-squared differences down to deltam(2) approximately 10(-18) eV(2) can be reached. We comment on the possibility of probing cosmological parameters with neutrinos. PMID:14753977

  19. Neutrino mass scale in the era of precision cosmology

    NASA Astrophysics Data System (ADS)

    Gerbino, M.

    2014-12-01

    In this work, we study how recent cosmological datasets in combination with particle physics results are able to constrain the neutrino mass scale. In particular, we present current bounds on the electron neutrino mass m?, the effective Majorana mass m?? and the total neutrino mass ?mv and we discuss the sensitivity required to future experiments in order to address the issue of neutrino hierarchy.

  20. Solar neutrinos and neutrino astronomy. AIP conference proceedings No. 126

    SciTech Connect

    Cherry, M.L.; Fowler, W.A.; Lande, K. (eds.)

    1985-01-01

    Topics covered include: present Homestake Laboratory scientific programs; understanding solar neutrino emission; new radiochemical solar neutrino experiments; other solar neutrino detectors; and neutrino astronomy. (GHT)

  1. Neutrino masses from new generations

    E-print Network

    Aparici, Alberto; Rius, Nuria; Santamaria, Arcadi

    2011-01-01

    We reconsider the possibility that Majorana masses for the three known neutrinos are generated radiatively by the presence of a fourth generation and one right-handed neutrino with Yukawa couplings and a Majorana mass term. We find that the observed light neutrino mass hierarchy is not compatible with low energy universality bounds in this minimal scenario, but all present data can be accommodated with five generations and two right-handed neutrinos. Within this framework, we explore the parameter space regions which are currently allowed and could lead to observable effects in neutrinoless double beta decay, $\\mu - e$ conversion in nuclei and $\\mu \\rightarrow e \\gamma$ experiments. We also discuss the detection prospects at LHC.

  2. Neutrinoless double-beta decay with three or four neutrino mixing

    Microsoft Academic Search

    Carlo Giunti

    2000-01-01

    Considering the scheme with mixing of three neutrinos and a mass hierarchy that can accommodate the results of solar and atmospheric neutrino experiments, it is shown that the results of solar neutrino experiments imply a lower bound for the effective Majorana mass in neutrinoless double-beta decay, under the natural assumptions that massive neutrinos are Majorana particles and there are no

  3. Geometric phase of neutrino propagating through dissipative matter

    SciTech Connect

    Dajka, J.; Syska, J.; Luczka, J. [Institute of Physics, University of Silesia, 40-007 Katowice (Poland)

    2011-05-01

    We study the geometric phase (GP) in neutrino oscillation for both Dirac and Majorana neutrinos. We apply the kinematic generalization of the GP to quantum open systems that take into account the coupling to a dissipative environment. In the dissipationless case, the GP does not depend on the Majorana angle. It is not the case in the presence of dissipation and hence the GP can serve as a tool determining the type of the Dirac vs the Majorana neutrino.

  4. A new spin on neutrino quantum kinetics

    NASA Astrophysics Data System (ADS)

    Cirigliano, Vincenzo; Fuller, George M.; Vlasenko, Alexey

    2015-07-01

    Recent studies have demonstrated that in anisotropic environments a coherent spin-flip term arises in the Quantum Kinetic Equations (QKEs) which govern the evolution of neutrino flavor and spin in hot and dense media. This term can mediate neutrino-antineutrino transformation for Majorana neutrinos and active-sterile transformation for Dirac neutrinos. We discuss the physical origin of the coherent spin-flip term and provide explicit expressions for the QKEs in a two-flavor model with spherical geometry. In this context, we demonstrate that coherent neutrino spin transformation depends on the absolute neutrino mass and Majorana phases. We discuss the physical origin of the coherent spin-flip term in the framework of an MSW-like effective Hamiltonian, in analogy to the spin-(flavor) oscillations induced by neutrino magnetic moments in a magnetic field. We provide explicit expressions for the coherent QKEs in a two-flavor model with spherical geometry, amenable for a computational implementation. This is the first step towards a realistic exploration of the impact of helicity oscillations in astrophysics environments. We point out the dependence of the QKEs (through the neutrino-antineutrino conversion term) on the neutrino absolute mass scale and Majorana phases. We also compare and contrast neutrino-less double beta decay and neutrino spin transformation in astrophysical environments as probes of these parameters.

  5. Textures for neutrino mass matrices

    SciTech Connect

    Leontaris, G.K.; Lola, S.; Scheich, C.; Vergados, J.D. [Theoretical Physics Division, Ioannina University, GR-45110 Ioannina (Greece)] [Theoretical Physics Division, Ioannina University, GR-45110 Ioannina (Greece); [Institut fuer Theoretische Physik, Univerisitaet Heidelberg, Philosophenweg 16, 69120 Heidelberg (Germany); [Departamento de Fisica Teorica, Universidad Autonoma de Madrid, 28049, Madrid (Spain); [Department of Natural Sciences, University of Cyprus, Nicosia (Cyprus)

    1996-06-01

    We give a classification of heavy Majorana neutrino mass matrices with up to three texture zeros, assuming the Dirac masses of the neutrinos to be of the same form as the ones of the up quarks in the five texture zero solutions for the quark matrices. This is the case for many unified and partially unified models. We find that it is possible to have solutions which account for the solar and atmospheric neutrino problems as well as the COBE observations simultaneously, and we motivate the existence of such solutions from symmetries. {copyright} {ital 1996 The American Physical Society.}

  6. Solar Neutrinos and the Decaying Neutrino Hypothesis

    E-print Network

    Jeffrey M. Berryman; Andre de Gouvea; Daniel Hernandez

    2014-11-02

    We explore, mostly using data from solar neutrino experiments, the hypothesis that the neutrino mass eigenstates are unstable. We find that, by combining $^8$B solar neutrino data with those on $^7$Be and lower-energy solar neutrinos, one obtains a mostly model-independent bound on both the $\

  7. GUT implications from neutrino mass

    NASA Astrophysics Data System (ADS)

    Albright, Carl H.

    2003-05-01

    An overview is given of the experimental neutrino mixing results and types of neutrino models proposed, with special attention to the general features of various GUT models involving intra-family symmetries and horizontal flavor symmetries. Many of the features are then illustrated by a specific SO(10) SUSY GUT model formulated by Barr and the author which can explain all four types of solar neutrino mixing solutions by various choices of the right-handed Majorana mass matrix. The quantitative nature of the model's large mixing angle solution is used to compare the reaches of a neutrino super-beam and a neutrino factory for determining the small Ue3 mixing matrix element.

  8. Solar Neutrinos

    E-print Network

    R. G. H. Robertson

    2006-02-05

    Experimental work with solar neutrinos has illuminated the properties of neutrinos and tested models of how the sun produces its energy. Three experiments continue to take data, and at least seven are in various stages of planning or construction. In this review, the current experimental status is summarized, and future directions explored with a focus on the effects of a non-zero theta-13 and the interesting possibility of directly testing the luminosity constraint. Such a confrontation at the few-percent level would provide a prediction of the solar irradiance tens of thousands of years in the future for comparison with the present-day irradiance. A model-independent analysis of existing low-energy data shows good agreement between the neutrino and electromagnetic luminosities at the +/- 20 % level.

  9. Neutrino masses, neutrino oscillations, and cosmological implications

    NASA Technical Reports Server (NTRS)

    Stecker, F. W.

    1982-01-01

    Theoretical concepts and motivations for considering neutrinos having finite masses are discussed and the experimental situation on searches for neutrino masses and oscillations is summarized. The solar neutrino problem, reactor, deep mine and accelerator data, tri decay experiments and double beta-decay data are considered and cosmological implications and astrophysical data relating to neutrino masses are reviewed. The neutrino oscillation solution to the solar neutrino problem, the missing mass problem in galaxy halos and galaxy cluster galaxy formation and clustering, and radiative neutrino decay and the cosmic ultraviolet background radiation are examined.

  10. A Bound on Neutrino Masses From Baryogenesis

    Microsoft Academic Search

    W. Buchmuller; P. Di Bari; M. Plumacher

    Properties of neutrinos, the lightest of all elementary particles, may be the origin of the entire matter-antimatter asymmetry of the universe. This requires that neu- trinos are Majorana particles, which are equal to their antiparticles, and that their masses are sufficiently small. Leptogenesis, the theory explaining the cosmic matter- antimatter asymmetry, predicts that all neutrino masses are smaller than 0.2

  11. Leptoquarks: Neutrino masses and related accelerator signals

    Microsoft Academic Search

    D. Aristizabal Sierra; M. Hirsch; S. G. Kovalenko

    2008-01-01

    Leptoquark-Higgs interactions induce mixing between leptoquark (LQ) states with different chiralities once the electroweak symmetry is broken. In such LQ models Majorana neutrino masses are generated at 1-loop order. Here we calculate the neutrino mass matrix and explore the constraints on the parameter space enforced by the assumption that LQ-loops explain current neutrino oscillation data. LQs will be produced at

  12. Leptoquarks: Neutrino masses and accelerator phenomenology

    Microsoft Academic Search

    D. Aristizabal Sierra; S. G. Kovalenko

    2007-01-01

    Leptoquark-Higgs interactions induce mixing between leptoquark states with\\u000adifferent chiralities once the electro-weak symmetry is broken. In such LQ\\u000amodels Majorana neutrino masses are generated at 1-loop order. Here we\\u000acalculate the neutrino mass matrix and explore the constraints on the parameter\\u000aspace enforced by the assumption that LQ-loops explain current neutrino\\u000aoscillation data. LQs will be produced at the

  13. Neutrino mixing in a grand unified theory

    SciTech Connect

    Milton, K.; Tanaka, K.

    1980-01-01

    Neutrino mixing in a grand unified theory in which the neutrino mass matrix is determined by the Gell-Mann-Ramond-Slansky mechanism was investigated. With an arbitrary real right-handed Majorana mass matrix which incorporates three neutrino mass scales, the effects of the up-quark mass matrix are found to be dominant and as a result no significant mixing of ..nu../sub e/ occurs, while ..nu../sub ..mu../ - ..nu../sub ..gamma../ mixing can be substantial.

  14. A bound on neutrino masses from baryogenesis

    Microsoft Academic Search

    W. Buchmuller; P. Di Bari; M. Plumacher

    2002-01-01

    Properties of neutrinos, the lightest of all elementary particles, may be the origin of the entire matter–antimatter asymmetry of the universe. This requires that neutrinos are Majorana particles, which are equal to their antiparticles, and that their masses are sufficiently small. Leptogenesis, the theory explaining the cosmic matter–antimatter asymmetry, predicts that all neutrino masses are smaller than 0.2 eV, which will

  15. Neutrino magnetic moment

    SciTech Connect

    Chang, D. (Northwestern Univ., Evanston, IL (USA). Dept. of Physics and Astronomy Fermi National Accelerator Lab., Batavia, IL (USA)); Senjanovic, G. (Zagreb Univ. (Yugoslavia). Dept. of Theoretical Physics)

    1990-01-01

    We review attempts to achieve a large neutrino magnetic moment ({mu}{sub {nu}} {le} 10{sup {minus}11}{mu}{sub B}), while keeping neutrino light or massless. The application to the solar neutrino puzzle is discussed. 24 refs.

  16. Electromagnetic properties of neutrinos

    E-print Network

    Carlo Giunti; Alexander Studenikin

    2010-06-08

    A short review on electromagnetic properties of neutrinos is presented. In spite of many efforts in the theoretical and experimental studies of neutrino electromagnetic properties, they still remain one of the main puzzles related to neutrinos.

  17. Pseudo-Dirac Neutrino Scenario: Cosmic Neutrinos at Neutrino Telescopes

    E-print Network

    Arman Esmaili

    2009-09-29

    Within the "pseudo-Dirac" scenario for massive neutrinos the existence of sterile neutrinos which are almost degenerate in mass with the active ones is hypothesized. The presence of these sterile neutrinos can affect the flavor composition of cosmic neutrinos arriving at Earth after traveling large distances from astrophysical objects. We examine the prospects of neutrino telescopes such as IceCube to probe the very tiny mass squared differences 10^(-12) eV^2pseudo-Dirac neutrino scenario and especially to discriminate it from the conventional scenario with no sterile neutrino. We also discuss the robustness of our results with respect to the uncertainties in the initial flavor ratio of neutrinos at the source.

  18. The Mystery of Neutrino Mixings

    NASA Astrophysics Data System (ADS)

    Altarelli, Guido

    2013-07-01

    In the last years we have learnt a lot about neutrino masses and mixings. Neutrinos are not all massless but their masses are very small. Probably masses are small because neutrinos are Majorana particles with masses inversely proportional to the large scale M of lepton number (L) violation, which turns out to be compatible with the GUT scale. We have understood that there is no contradiction between large neutrino mixings and small quark mixings, even in the context of GUTs and that neutrino masses fit well in the SUSY GUT picture. Out of equilibrium decays with CP and L violation of heavy RH neutrinos can produce a B-L asymmetry, then converted near the weak scale by instantons into an amount of B asymmetry compatible with observations (baryogenesis via leptogenesis). It appears that active neutrinos are not a significant component of Dark Matter in the Universe. A long list of models have been formulated over the years to understand neutrino masses and mixings. With the continuous improvement of the data most of the models have been discarded by experiment. The surviving models still span a wide range going from a maximum of symmetry, with discrete non-abelian flavour groups, to the opposite extreme of anarchy.

  19. Vanishing effective mass of the neutrinoless double beta decay including light sterile neutrinos

    E-print Network

    Y. F. Li; Si-shuo Liu

    2011-11-28

    Light sterile neutrinos with masses at the sub-eV or eV scale are hinted by current experimental and cosmological data. Assuming the Majorana nature of these hypothetical particles, we discuss their effects in the neutrinoless double beta decay by exploring the implications of a vanishing effective Majorana neutrino mass. Allowed ranges of neutrino masses, mixing angles and Majorana CP-violating phases are illustrated in some instructive cases for both normal and inverted mass hierarchies of three active neutrinos.

  20. NEUTRINO FACTORIES - PHYSICS POTENTIALS.

    SciTech Connect

    PARSA,Z.

    2001-02-16

    The recent results from Super-Kamiokande atmospheric and solar neutrino observations opens a new era in neutrino physics and has sparked a considerable interest in the physics possibilities with a Neutrino Factory based on the muon storage ring. We present physics opportunities at a Neutrino Factory, and prospects of Neutrino oscillation experiments. Using the precisely known flavor composition of the beam, one could envision an extensive program to measure the neutrino oscillation mixing matrix, including possible CP violating effects. These and Neutrino Interaction Rates for examples of a Neutrino Factory at BNL (and FNAL) with detectors at Gran Sasso, SLAC and Sudan are also presented.

  1. Neutrinos: Theory and Phenomenology

    SciTech Connect

    Parke, Stephen

    2013-10-22

    The theory and phenomenology of neutrinos will be addressed, especially that relating to the observation of neutrino flavor transformations. The current status and implications for future experiments will be discussed with special emphasis on the experiments that will determine the neutrino mass ordering, the dominant flavor content of the neutrino mass eigenstate with the smallest electron neutrino content and the size of CP violation in the neutrino sector. Beyond the neutrino Standard Model, the evidence for and a possible definitive experiment to confirm or refute the existence of light sterile neutrinos will be briefly discussed.

  2. The Intermediate Neutrino Program

    E-print Network

    Adams, C; Ankowski, A M; Asaadi, J A; Ashenfelter, J; Axani, S N; Babu, K; Backhouse, C; Band, H R; Barbeau, P S; Barros, N; Bernstein, A; Betancourt, M; Bishai, M; Blucher, E; Bouffard, J; Bowden, N; Brice, S; Bryan, C; Camilleri, L; Cao, J; Carlson, J; Carr, R E; Chatterjee, A; Chen, M; Chen, S; Chiu, M; Church, E D; Collar, J I; Collin, G; Conrad, J M; Convery, M R; Cooper, R L; Cowen, D; Davoudiasl, H; De Gouvea, A; Dean, D J; Deichert, G; Descamps, F; DeYoung, T; Diwan, M V; Djurcic, Z; Dolinski, M J; Dolph, J; Donnelly, B; Dwyer, D A; Dytman, S; Efremenko, Y; Everett, L L; Fava, A; Figueroa-Feliciano, E; Fleming, B; Friedland, A; Fujikawa, B K; Gaisser, T K; Galeazzi, M; Galehouse, D C; Galindo-Uribarri, A; Garvey, G T; Gautam, S; Gilje, K E; Gonzalez-Garcia, M; Goodman, M C; Gordon, H; Gramellini, E; Green, M P; Guglielmi, A; Hackenburg, R W; Hackenburg, A; Halzen, F; Han, K; Hans, S; Harris, D; Heeger, K M; Herman, M; Hill, R; Holin, A; Huber, P; Jaffe, D E; Johnson, R A; Joshi, J; Karagiorgi, G; Kaufman, L J; Kayser, B; Kettell, S H; Kirby, B J; Klein, J R; Kolomensky, Yu G; Kriske, R M; Lane, C E; Langford, T J; Lankford, A; Lau, K; Learned, J G; Ling, J; Link, J M; Lissauer, D; Littenberg, L; Littlejohn, B R; Lockwitz, S; Lokajicek, M; Louis, W C; Luk, K; Lykken, J; Marciano, W J; Maricic, J; Markoff, D M; Caicedo, D A Martinez; Mauger, C; Mavrokoridis, K; McCluskey, E; McKeen, D; McKeown, R; Mills, G; Mocioiu, I; Monreal, B; Mooney, M R; Morfin, J G; Mumm, P; Napolitano, J; Neilson, R; Nelson, J K; Nessi, M; Norcini, D; Nova, F; Nygren, D R; Gann, G D Orebi; Palamara, O; Parsa, Z; Patterson, R; Paul, P; Pocar, A; Qian, X; Raaf, J L; Rameika, R; Ranucci, G; Ray, H; Reyna, D; Rich, G C; Rodrigues, P; Romero, E Romero; Rosero, R; Rountree, S D; Rybolt, B; Sanchez, M C; Santucci, G; Schmitz, D; Scholberg, K; Seckel, D; Shaevitz, M; Shrock, R; Smy, M B; Soderberg, M; Sonzogni, A; Sousa, A B; Spitz, J; John, J M St; Stewart, J; Strait, J B; Sullivan, G; Svoboda, R; Szelc, A M; Tayloe, R; Thomson, M A; Toups, M; Vacheret, A; Vagins, M; Van de Water, R G; Vogelaar, R B; Weber, M; Weng, W; Wetstein, M; White, C; White, B R; Whitehead, L; Whittington, D W; Wilking, M J; Wilson, R J; Wilson, P; Winklehner, D; Winn, D R; Worcester, E; Yang, L; Yeh, M; Yokley, Z W; Yoo, J; Yu, B; Yu, J; Zhang, C

    2015-01-01

    The US neutrino community gathered at the Workshop on the Intermediate Neutrino Program (WINP) at Brookhaven National Laboratory February 4-6, 2015 to explore opportunities in neutrino physics over the next five to ten years. Scientists from particle, astroparticle and nuclear physics participated in the workshop. The workshop examined promising opportunities for neutrino physics in the intermediate term, including possible new small to mid-scale experiments, US contributions to large experiments, upgrades to existing experiments, R&D plans and theory. The workshop was organized into two sets of parallel working group sessions, divided by physics topics and technology. Physics working groups covered topics on Sterile Neutrinos, Neutrino Mixing, Neutrino Interactions, Neutrino Properties and Astrophysical Neutrinos. Technology sessions were organized into Theory, Short-Baseline Accelerator Neutrinos, Reactor Neutrinos, Detector R&D and Source, Cyclotron and Meson Decay at Rest sessions.This report summ...

  3. Minimal Schemes for Large Neutrino Mixings with Inverted Hierarchy

    E-print Network

    Duane A. Dicus; Hong-Jian He; John N. Ng

    2002-05-17

    Existing oscillation data point to nonzero neutrino masses with large mixings. We analyze the generic features of the neutrino Majorana mass matrix with inverted hierarchy and construct realistic {\\it minimal schemes} for the neutrino mass matrix that can explain the large (but not maximal) \

  4. Atmospheric neutrino and Long Baseline neutrino experiments

    E-print Network

    Giorgio Giacomelli

    2007-12-13

    The results obtained by several experiments on atmospheric neutrino oscillations are summarized and discussed. Then the results obtained by different long baseline neutrino experiments are considered. Finally conclusions and perspectives are made.

  5. Calculating Neutrino Oscillations with Sterile Neutrinos

    NASA Astrophysics Data System (ADS)

    Linehan, Bryan

    2014-09-01

    In particle physics, it is currently known that three types of neutrinos exist that interact via the weak force. Referred to as ``flavors,'' they are distinguishable and named for the lepton they produce through charged current interactions: electron, muon, and tau. In a process called neutrino oscillation, one flavor of neutrino can change into another flavor as it propagates through space. At the moment, mild discrepancies between expected and measured neutrino oscillations suggest that more types of neutrinos that do not interact via the weak force exist: sterile neutrinos. The goal of this project was to calculate non-sterile flavor oscillation probabilities when 1, 2 or 3 sterile neutrinos were assumed to exist. An application has been written in Mathematica that calculates these probabilities with the neutrino masses, linear relationships between mass and flavor states, values of CP symmetry violating constants, and constant densities of media in which the neutrinos propagate set as parameters. The application was published online for researchers to use as a tool when considering the existence of sterile neutrinos. In the immediate future, the insights this application gives into neutrino oscillations will be studied and reported. In particle physics, it is currently known that three types of neutrinos exist that interact via the weak force. Referred to as ``flavors,'' they are distinguishable and named for the lepton they produce through charged current interactions: electron, muon, and tau. In a process called neutrino oscillation, one flavor of neutrino can change into another flavor as it propagates through space. At the moment, mild discrepancies between expected and measured neutrino oscillations suggest that more types of neutrinos that do not interact via the weak force exist: sterile neutrinos. The goal of this project was to calculate non-sterile flavor oscillation probabilities when 1, 2 or 3 sterile neutrinos were assumed to exist. An application has been written in Mathematica that calculates these probabilities with the neutrino masses, linear relationships between mass and flavor states, values of CP symmetry violating constants, and constant densities of media in which the neutrinos propagate set as parameters. The application was published online for researchers to use as a tool when considering the existence of sterile neutrinos. In the immediate future, the insights this application gives into neutrino oscillations will be studied and reported. Mentored by Dr. Michael Kordosky and supported by the National Science Foundation under Grant No. PHY-1359364.

  6. Ultra High Energy Neutrino Astronomy

    E-print Network

    V. Berezinsky

    2005-05-11

    The short review of theoretical aspects of ultra high energy (UHE) neutrinos and superGZK neutrinos. The sources and diffuse fluxes of UHE neutrinos are discussed. Much attention is given to comparison of the cascade and cosmic ray upper bounds for diffuse neutrino fluxes. Cosmogenic neutrinos and neutrinos from the mirror mater are considered as superGZK neutrinos.

  7. Long Baseline Neutrino Oscillations

    SciTech Connect

    Rebel, Brian; /Fermilab

    2009-10-01

    There is compelling evidence for neutrino flavor change as neutrinos propagate. The evidence for this phenomenon has been provided by several experiments observing neutrinos that traverse distances of several hundred kilometers between production and detection. This review outlines the evidence for neutrino flavor change from such experiments and describes recent results in the field.

  8. The Sudbury Neutrino Observatory

    Microsoft Academic Search

    J. J. Simpson

    2001-01-01

    The Sudbury Neutrino Observatory (SNO) is a large, underground heavywater Cerenkov detector which has been designed and built primarily to solve the solar neutrino problem, the shortfall in the flux of neutrinos coming from the sun relative to the best solar model predictions. As discussed in previous talks in this symposium, the neutrino flux shortfall occurs in all previous experiments

  9. Future Neutrino Experiments

    SciTech Connect

    Fleming, B. T. [Physics Department, Yale University, New Haven, CT 60510 (United States)

    2009-12-17

    There are a number of future neutrino experiments addressing fundamental questions about the neutrino and about what the neutrino can tell us about the universe. A class of these experiments are long baseline neutrino oscillation v{sub e} appearance searches which can measure the final unknowns of the 3x3 neutrino mixing matrix and look for CP violation in the neutrino sector. The massive detectors needed for these experiments can also search for proton decay and measure extra-terrestrial neutrino sources. There are a number of efforts worldwide to launch these experiments. These efforts, with a focus on US plans, are described.

  10. The cosmic neutrino background

    NASA Technical Reports Server (NTRS)

    Dar, Arnon

    1991-01-01

    The cosmic neutrino background is expected to consist of relic neutrinos from the big bang, of neutrinos produced during nuclear burning in stars, of neutrinos released by gravitational stellar collapse, and of neutrinos produced by cosmic ray interactions with matter and radiation in the interstellar and intergalactic medium. Formation of baryonic dark matter in the early universe, matter-antimatter annihilation in a baryonic symmetric universe, and dark matter annihilation could have also contributed significantly to the cosmic neutrino background. The purpose of this paper is to review the properties of these cosmic neutrino backgrounds, the indirect evidence for their existence, and the prospects for their detection.

  11. Neutrino Physics with JUNO

    E-print Network

    An, Fengpeng; An, Qi; Antonelli, Vito; Baussan, Eric; Beacom, John; Bezrukov, Leonid; Blyth, Simon; Brugnera, Riccardo; Avanzini, Margherita Buizza; Busto, Jose; Cabrera, Anatael; Cai, Hao; Cai, Xiao; Cammi, Antonio; Cao, Guofu; Cao, Jun; Chang, Yun; Chen, Shaomin; Chen, Shenjian; Chen, Yixue; Chiesa, Davide; Clemenza, Massimiliano; Clerbaux, Barbara; Conrad, Janet; D'Angelo, Davide; De Kerret, Herve; Deng, Zhi; Deng, Ziyan; Ding, Yayun; Djurcic, Zelimir; Dornic, Damien; Dracos, Marcos; Drapier, Olivier; Dusini, Stefano; Dye, Stephen; Enqvist, Timo; Fan, Donghua; Fang, Jian; Favart, Laurent; Ford, Richard; Goger-Neff, Marianne; Gan, Haonan; Garfagnini, Alberto; Giammarchi, Marco; Gonchar, Maxim; Gong, Guanghua; Gong, Hui; Gonin, Michel; Grassi, Marco; Grewing, Christian; Guan, Mengyun; Guarino, Vic; Guo, Gang; Guo, Wanlei; Guo, Xin-Heng; Hagner, Caren; Han, Ran; He, Miao; Heng, Yuekun; Hsiung, Yee; Hu, Jun; Hu, Shouyang; Hu, Tao; Huang, Hanxiong; Huang, Xingtao; Huo, Lei; Ioannisian, Ara; Jeitler, Manfred; Ji, Xiangdong; Jiang, Xiaoshan; Jollet, Cecile; Kang, Li; Karagounis, Michael; Kazarian, Narine; Krumshteyn, Zinovy; Kruth, Andre; Kuusiniemi, Pasi; Lachenmaier, Tobias; Leitner, Rupert; Li, Chao; Li, Jiaxing; Li, Weidong; Li, Weiguo; Li, Xiaomei; Li, Xiaonan; Li, Yi; Li, Yufeng; Li, Zhi-Bing; Liang, Hao; Lin, Guey-Lin; Lin, Tao; Lin, Yen-Hsun; Ling, Jiajie; Lippi, Ivano; Liu, Dawei; Liu, Hongbang; Liu, Hu; Liu, Jianglai; Liu, Jianli; Liu, Jinchang; Liu, Qian; Liu, Shubin; Liu, Shulin; Lombardi, Paolo; Long, Yongbing; Lu, Haoqi; Lu, Jiashu; Lu, Jingbin; Lu, Junguang; Lubsandorzhiev, Bayarto; Ludhova, Livia; Luo, Shu; Lyashuk, Vladimir; Mollenberg, Randolph; Ma, Xubo; Mantovani, Fabio; Mao, Yajun; Mari, Stefano M; McDonough, William F; Meng, Guang; Meregaglia, Anselmo; Meroni, Emanuela; Mezzetto, Mauro; Miramonti, Lino; Mueller, Thomas; Naumov, Dmitry; Oberauer, Lothar; Ochoa-Ricoux, Juan Pedro; Olshevskiy, Alexander; Ortica, Fausto; Paoloni, Alessandro; Peng, Haiping; Peng, Jen-Chieh; Previtali, Ezio; Qi, Ming; Qian, Sen; Qian, Xin; Qian, Yongzhong; Qin, Zhonghua; Raffelt, Georg; Ranucci, Gioacchino; Ricci, Barbara; Robens, Markus; Romani, Aldo; Ruan, Xiangdong; Ruan, Xichao; Salamanna, Giuseppe; Shaevitz, Mike; Sinev, Valery; Sirignano, Chiara; Sisti, Monica; Smirnov, Oleg; Soiron, Michael; Stahl, Achim; Stanco, Luca; Steinmann, Jochen; Sun, Xilei; Sun, Yongjie; Taichenachev, Dmitriy; Tang, Jian; Tkachev, Igor; Trzaska, Wladyslaw; van Waasen, Stefan; Volpe, Cristina; Vorobel, Vit; Votano, Lucia; Wang, Chung-Hsiang; Wang, Guoli; Wang, Hao; Wang, Meng; Wang, Ruiguang; Wang, Siguang; Wang, Wei; Wang, Yi; Wang, Yifang; Wang, Zhe; Wang, Zheng; Wang, Zhigang; Wang, Zhimin; Wei, Wei; Wen, Liangjian; Wiebusch, Christopher; Wonsak, Bjorn; Wu, Qun; Wulz, Claudia-Elisabeth; Wurm, Michael; Xi, Yufei; Xia, Dongmei; Xie, Yuguang; Xing, Zhi-zhong; Xu, Jilei; Yan, Baojun; Yang, Changgen; Yang, Chaowen; Yang, Guang; Yang, Lei; Yang, Yifan; Yao, Yu; Yegin, Ugur; Yermia, Frederic; You, Zhengyun; Yu, Boxiang; Yu, Chunxu; Yu, Zeyuan; Zavatarelli, Sandra; Zhan, Liang; Zhang, Chao; Zhang, Hong-Hao; Zhang, Jiawen; Zhang, Jingbo; Zhang, Qingmin; Zhang, Yu-Mei; Zhang, Zhenyu; Zhao, Zhenghua; Zheng, Yangheng; Zhong, Weili; Zhou, Guorong; Zhou, Jing; Zhou, Li; Zhou, Rong; Zhou, Shun; Zhou, Wenxiong; Zhou, Xiang; Zhou, Yeling; Zhou, Yufeng; Zou, Jiaheng

    2015-01-01

    The Jiangmen Underground Neutrino Observatory (JUNO), a 20 kton multi-purpose underground liquid scintillator detector, was proposed with the determination of the neutrino mass hierarchy as a primary physics goal. It is also capable of observing neutrinos from terrestrial and extra-terrestrial sources, including supernova burst neutrinos, diffuse supernova neutrino background, geoneutrinos, atmospheric neutrinos, solar neutrinos, as well as exotic searches such as nucleon decays, dark matter, sterile neutrinos, etc. We present the physics motivations and the anticipated performance of the JUNO detector for various proposed measurements. By detecting reactor antineutrinos from two power plants at 53-km distance, JUNO will determine the neutrino mass hierarchy at a 3-4 sigma significance with six years of running. The measurement of antineutrino spectrum will also lead to the precise determination of three out of the six oscillation parameters to an accuracy of better than 1\\%. Neutrino burst from a typical cor...

  12. Measuring anisotropies in the cosmic neutrino background

    NASA Astrophysics Data System (ADS)

    Lisanti, Mariangela; Safdi, Benjamin R.; Tully, Christopher G.

    2014-10-01

    Neutrino capture on tritium has emerged as a promising method for detecting the cosmic neutrino background (C ? B ). We show that relic neutrinos are captured most readily when their spin vectors are antialigned with the polarization axis of the tritium nuclei and when they approach along the direction of polarization. As a result, C ? B observatories may measure anisotropies in the cosmic neutrino velocity and spin distributions by polarizing the tritium targets. A small dipole anisotropy in the C ? B is expected due to the peculiar velocity of the lab frame with respect to the cosmic frame and due to late-time gravitational effects. The PTOLEMY experiment, a tritium observatory currently under construction, should observe a nearly isotropic background. This would serve as a strong test of the cosmological origin of a potential signal. The polarized-target measurements may also constrain nonstandard neutrino interactions that would induce larger anisotropies and help discriminate between Majorana versus Dirac neutrinos.

  13. Neutrino Mixing from CP Symmetry

    E-print Network

    Chen, Peng; Ding, Gui-Jun

    2015-01-01

    The neutrino mass matrix has remnant CP symmetry expressed in terms of the lepton mixing matrix, and vice versa the remnant CP transformations allow us to reconstruct the mixing matrix. We study the scenario that all the four remnant CP transformations are preserved by the neutrino mass matrix. The most general parameterization of remnant CP transformations is presented. The lepton mixing matrix is completely fixed by the remnant CP, and its explicit form is derived. The necessary and sufficient condition for conserved Dirac CP violating phase is found. If the Klein four flavor symmetry generated by the postulated remnant CP transformations arises from a finite flavor symmetry group, the phenomenologically viable lepton flavor mixing would be the trimaximal pattern, both Dirac CP phase $\\delta_{CP}$ and Majorana phase $\\alpha_{31}$ are either $0$ or $\\pi$ while another Majorana phase $\\alpha_{21}$ is a rational multiple of $\\pi$. These general results are confirmed to be true in the case that the finite flavo...

  14. Neutrino Nucleosynthesis in Supernovae

    SciTech Connect

    Yoshida, Takashi [Division of Theoretical Astronomy, National Astronomical Observatory of Japan (Japan); Suzuki, Toshio [Department of Physics, College of Humanities and Sciences, Nihon University (Japan); Chiba, Satoshi [Advanced Science Research Center, Japan Atomic Energy Agency (Japan); Kajino, Toshitaka [Division of Theoretical Astronomy, National Astronomical Observatory of Japan (Japan); Department of Astronomy, Graduate School of Science, University of Tokyo (Japan); Yokomakura, Hidekazu; Kimura, Keiichi [Department of Physics, Graduate School of Science, Nagoya University (Japan); Takamura, Akira [Department of Mathematics, Toyota National College of Technology (Japan); Hartmann, Dieter H. [Department of Physics and Astronomy, Clemson University (United States)

    2009-05-04

    Neutrino nucleosynthesis is an important synthesis process for light elements in supernovae. One important physics input of neutrino nucleosynthesis is cross sections of neutrino-nucleus reactions. The cross sections of neutrino-{sup 12}C and {sup 4}He reactions are derived using new shell model Hamiltonians. With the new cross sections, light element synthesis of a supernova is investigated. The appropriate range of the neutrino temperature for supernovae is constrained to be between 4.3 MeV and 6.5 MeV from the {sup 11}B abundance in Galactic chemical evolution. Effects by neutrino oscillations are also discussed.

  15. Neutrino Physics at Fermilab

    ScienceCinema

    Niki Saoulidou

    2010-01-08

    Neutrino oscillations provide the first evidence for physics beyond the Standard Model. I will briefly overview the neutrino "hi-story", describing key discoveries over the past decades that shaped our understanding of neutrinos and their behavior. Fermilab was, is and hopefully will be at the forefront of the accelerator neutrino experiments.  NuMI, the most powerful accelerator neutrino beam in the world has ushered us into the era of precise measurements. Its further upgrades may give a chance to tackle the remaining mysteries of the neutrino mass hierarchy and possible CP violation.

  16. Solar Neutrinos: History

    NSDL National Science Digital Library

    Bahcall, John

    This site, authored by John Bahcall of the School of Natural Sciences, offers several articles about neutrinos, the neutrino oscillations, and the sun. The page is structured in this fashion: a historical overview of solar models, a theoretical description of solar neutrinos, an experimental description of solar neutrinos, an explanation of how the sun shines, and the evolution of neutrino astronomy. The page links users to pdfs of useful papers concerning these topics. This is a useful resource for those looking for a comprehensive history of solar neutrinos.

  17. Neutrino Physics with JUNO

    E-print Network

    Fengpeng An; Guangpeng An; Qi An; Vito Antonelli; Eric Baussan; John Beacom; Leonid Bezrukov; Simon Blyth; Riccardo Brugnera; Margherita Buizza Avanzini; Jose Busto; Anatael Cabrera; Hao Cai; Xiao Cai; Antonio Cammi; Guofu Cao; Jun Cao; Yun Chang; Shaomin Chen; Shenjian Chen; Yixue Chen; Davide Chiesa; Massimiliano Clemenza; Barbara Clerbaux; Janet Conrad; Davide D'Angelo; Herve De Kerret; Zhi Deng; Ziyan Deng; Yayun Ding; Zelimir Djurcic; Damien Dornic; Marcos Dracos; Olivier Drapier; Stefano Dusini; Stephen Dye; Timo Enqvist; Donghua Fan; Jian Fang; Laurent Favart; Richard Ford; Marianne Goger-Neff; Haonan Gan; Alberto Garfagnini; Marco Giammarchi; Maxim Gonchar; Guanghua Gong; Hui Gong; Michel Gonin; Marco Grassi; Christian Grewing; Mengyun Guan; Vic Guarino; Gang Guo; Wanlei Guo; Xin-Heng Guo; Caren Hagner; Ran Han; Miao He; Yuekun Heng; Yee Hsiung; Jun Hu; Shouyang Hu; Tao Hu; Hanxiong Huang; Xingtao Huang; Lei Huo; Ara Ioannisian; Manfred Jeitler; Xiangdong Ji; Xiaoshan Jiang; Cecile Jollet; Li Kang; Michael Karagounis; Narine Kazarian; Zinovy Krumshteyn; Andre Kruth; Pasi Kuusiniemi; Tobias Lachenmaier; Rupert Leitner; Chao Li; Jiaxing Li; Weidong Li; Weiguo Li; Xiaomei Li; Xiaonan Li; Yi Li; Yufeng Li; Zhi-Bing Li; Hao Liang; Guey-Lin Lin; Tao Lin; Yen-Hsun Lin; Jiajie Ling; Ivano Lippi; Dawei Liu; Hongbang Liu; Hu Liu; Jianglai Liu; Jianli Liu; Jinchang Liu; Qian Liu; Shubin Liu; Shulin Liu; Paolo Lombardi; Yongbing Long; Haoqi Lu; Jiashu Lu; Jingbin Lu; Junguang Lu; Bayarto Lubsandorzhiev; Livia Ludhova; Shu Luo; Vladimir Lyashuk; Randolph Mollenberg; Xubo Ma; Fabio Mantovani; Yajun Mao; Stefano M. Mari; William F. McDonough; Guang Meng; Anselmo Meregaglia; Emanuela Meroni; Mauro Mezzetto; Lino Miramonti; Thomas Mueller; Dmitry Naumov; Lothar Oberauer; Juan Pedro Ochoa-Ricoux; Alexander Olshevskiy; Fausto Ortica; Alessandro Paoloni; Haiping Peng; Jen-Chieh Peng; Ezio Previtali; Ming Qi; Sen Qian; Xin Qian; Yongzhong Qian; Zhonghua Qin; Georg Raffelt; Gioacchino Ranucci; Barbara Ricci; Markus Robens; Aldo Romani; Xiangdong Ruan; Xichao Ruan; Giuseppe Salamanna; Mike Shaevitz; Valery Sinev; Chiara Sirignano; Monica Sisti; Oleg Smirnov; Michael Soiron; Achim Stahl; Luca Stanco; Jochen Steinmann; Xilei Sun; Yongjie Sun; Dmitriy Taichenachev; Jian Tang; Igor Tkachev; Wladyslaw Trzaska; Stefan van Waasen; Cristina Volpe; Vit Vorobel; Lucia Votano; Chung-Hsiang Wang; Guoli Wang; Hao Wang; Meng Wang; Ruiguang Wang; Siguang Wang; Wei Wang; Yi Wang; Yi Wang; Yifang Wang; Zhe Wang; Zheng Wang; Zhigang Wang; Zhimin Wang; Wei Wei; Liangjian Wen; Christopher Wiebusch; Bjorn Wonsak; Qun Wu; Claudia-Elisabeth Wulz; Michael Wurm; Yufei Xi; Dongmei Xia; Yuguang Xie; Zhi-zhong Xing; Jilei Xu; Baojun Yan; Changgen Yang; Chaowen Yang; Guang Yang; Lei Yang; Yifan Yang; Yu Yao; Ugur Yegin; Frederic Yermia; Zhengyun You; Boxiang Yu; Chunxu Yu; Zeyuan Yu; Sandra Zavatarelli; Liang Zhan; Chao Zhang; Hong-Hao Zhang; Jiawen Zhang; Jingbo Zhang; Qingmin Zhang; Yu-Mei Zhang; Zhenyu Zhang; Zhenghua Zhao; Yangheng Zheng; Weili Zhong; Guorong Zhou; Jing Zhou; Li Zhou; Rong Zhou; Shun Zhou; Wenxiong Zhou; Xiang Zhou; Yeling Zhou; Yufeng Zhou; Jiaheng Zou

    2015-07-20

    The Jiangmen Underground Neutrino Observatory (JUNO), a 20 kton multi-purpose underground liquid scintillator detector, was proposed with the determination of the neutrino mass hierarchy as a primary physics goal. It is also capable of observing neutrinos from terrestrial and extra-terrestrial sources, including supernova burst neutrinos, diffuse supernova neutrino background, geoneutrinos, atmospheric neutrinos, solar neutrinos, as well as exotic searches such as nucleon decays, dark matter, sterile neutrinos, etc. We present the physics motivations and the anticipated performance of the JUNO detector for various proposed measurements. By detecting reactor antineutrinos from two power plants at 53-km distance, JUNO will determine the neutrino mass hierarchy at a 3-4 sigma significance with six years of running. The measurement of antineutrino spectrum will also lead to the precise determination of three out of the six oscillation parameters to an accuracy of better than 1\\%. Neutrino burst from a typical core-collapse supernova at 10 kpc would lead to ~5000 inverse-beta-decay events and ~2000 all-flavor neutrino-proton elastic scattering events in JUNO. Detection of DSNB would provide valuable information on the cosmic star-formation rate and the average core-collapsed neutrino energy spectrum. Geo-neutrinos can be detected in JUNO with a rate of ~400 events per year, significantly improving the statistics of existing geoneutrino samples. The JUNO detector is sensitive to several exotic searches, e.g. proton decay via the $p\\to K^++\\bar\

  18. Some Unsettled Questions in the Problem of Neutrino Oscillations

    E-print Network

    Kh. M. Beshtoev

    2002-12-15

    It is noted that the theory of neutrino oscillations can be constructed only in the framework of the particle physics theory, where is a mass shell conception and then transitions (oscillations) between neutrinos with equal masses are real and between neutrinos with different masses are virtual. It is necessary to solve the question: which type of neutrino transitions (oscillations) is realized in nature? There can be three types of neutrino transitions (oscillations). At present it is considered that Dirac and Majorana neutrino oscillations can be realized. It is shown that we cannot put Majorana neutrinos in the standard weak interactions theory without violation of the gauge invariance. Then it is obvious that there can be only realized transitions (oscillations) between Dirac neutrinos with different flowers. Also it is shown that the mechanism of resonance enhancement of neutrino oscillations in matter cannot be realized without violation of the law of energy-momentum conservation. Though it is supposed that we see neutrino oscillations in experiments, indeed there only transitions between neutrinos are registered. In order to register neutrino oscillations it is necessary to see second or even higher neutrino oscillation modes in experiments. For this purpose we can use the elliptic character of the Earth orbit. The analysis shows that the SNO experimental results do not confirm smallest of nu_e to nu_\\tau transition angle mixings, which was obtained in CHOOZ experiment. It is also noted that there is contradiction between SNO, Super-Kamiokande, Homestake and the SAGE and GNO (GALLEX) data.

  19. PREFACE: Nobel Symposium 129 on Neutrino Physics

    NASA Astrophysics Data System (ADS)

    Bergström, Lars; Botner, Olga; Carlson, Per; Hulth, Per Olof; Ohlsson, Tommy

    2005-01-01

    Nobel Symposium 129 on Neutrino Physics was held at Haga Slott in Enköping, Sweden during August 19 24, 2004. Invited to the symposium were around 40 globally leading researchers in the field of neutrino physics, both experimental and theoretical. In addition to these participants, some 30 local researchers and graduate students participated in the symposium. The dominant theme of the lectures was neutrino oscillations, which after several years were recently verified by results from the Super-Kamiokande detector in Kamioka, Japan and the SNO detector in Sudbury, Canada. Discussion focused especially on effects of neutrino oscillations derived from the presence of matter and the fact that three different neutrinos exist. Since neutrino oscillations imply that neutrinos have mass, this is the first experimental observation that fundamentally deviates from the standard model of particle physics. This is a challenge to both theoretical and experimental physics. The various oscillation parameters will be determined with increased precision in new, specially designed experiments. Theoretical physics is working intensively to insert the knowledge that neutrinos have mass into the theoretical models that describe particle physics. It will probably turn out that the discovery of neutrino oscillations signifies a breakthrough in the description of the very smallest constituents of matter. The lectures provided a very good description of the intensive situation in the field right now. The topics discussed also included mass models for neutrinos, neutrinos in extra dimensions as well as the `seesaw mechanism', which provides a good description of why neutrino masses are so small. Also discussed, besides neutrino oscillations, was the new field of neutrino astronomy. Among the questions that neutrino astronomy hopes to answer are what the dark matter in the Universe consists of and where cosmic radiation at extremely high energies comes from. For this purpose, large neutrino telescopes are built deep in the Antarctic ice, in the Baikal Lake, and in the Mediterranean Sea. Among prominent unanswered questions, highlighted as one of the most important, was whether neutrinos are Dirac or Majorana particles. By studying neutrino double beta decay, researchers hope to answer this question, but it will put very large demands on detectors. The programme also included ample time for lively and valuable discussions, which cannot normally be held at ordinary conferences. The symposium concluded with a round-table discussion, where participants discussed the future of neutrino physics.Without a doubt, neutrino physics today is moving toward a very exciting and interesting period. An important contribution to the success of the symposium was the wonderful setting that the Haga Slott manor house hotel and conference center offered to the participants.

  20. Double Beta Decays and Neutrino Masses

    Microsoft Academic Search

    Hiroyasu Ejiri

    2005-01-01

    Neutrino-less double beta decays (0nu beta beta), which violate the lepton number conservation law by Delta L= 2, are of great interest for studying the fundamental properties of neutrinos beyond the standard electroweak theory. High-sensitivity 0 nu beta beta studies with mass sensitivities of the solar and atmospheric nu-masses are crucial for studying the Majorana nature of nu's, the nu

  1. Naturally small Dirac neutrino masses in supergravity

    SciTech Connect

    Abel, Steven; Dedes, Athanasios [Institute for Particle Physics Phenomenology (IPPP), Durham DH1 3LE (United Kingdom); Tamvakis, Kyriakos [Physics Department, University of Ioannina, GR 451 10, Ioannina (Greece)

    2005-02-01

    We show that Dirac neutrino masses of the right size can arise from the Kaehler potential of supergravity. They are proportional to the supersymmetry and the electroweak breaking scales. We find that they have the experimentally observed value provided that the ultraviolet cutoff of the Minimal Supersymmetric Standard Model is between the Grand Unification scale and the heterotic string scale. If lepton number is not conserved, then relatively suppressed Majorana masses can also be present, resulting in pseudo-Dirac neutrino masses.

  2. Neutrino mixing and CP phase correlations

    NASA Astrophysics Data System (ADS)

    Ma, Ernest; Natale, Alexander; Popov, Oleg

    2015-06-01

    A special form of the 3 × 3 Majorana neutrino mass matrix derivable from ?- ? interchange symmetry accompanied by a generalized CP transformation was obtained many years ago. It predicts ?23 = ? / 4 as well as ?CP = ± ? / 2, with ?13 ? 0. Whereas this is consistent with present data, we explore a deviation of this result which occurs naturally in a recent proposed model of radiative inverse seesaw neutrino mass.

  3. Matter–antimatter asymmetry and neutrino properties

    Microsoft Academic Search

    Wilfried Buchmüller; Michael Plümacher

    1999-01-01

    The cosmological baryon asymmetry can be explained as remnant of heavy Majorana neutrino decays in the early universe. We study this mechanism for two models of neutrino masses with a large ????? mixing angle which are based on the symmetries SU(5)×U(1)F and SU(3)c×SU(3)L×SU(3)R×U(1)F, respectively. In both cases B?L is broken at the unification scale ?GUT. The models make different predictions

  4. Oscillations of Mossbauer neutrinos

    E-print Network

    Evgeny Kh. Akhmedov; Joachim Kopp; Manfred Lindner

    2008-05-02

    We calculate the probability of recoilless emission and detection of neutrinos (Mossbauer effect with neutrinos) taking into account the boundedness of the parent and daughter nuclei in the neutrino source and detector as well as the leptonic mixing. We show that, in spite of their near monochromaticity, the recoillessly emitted and captured neutrinos oscillate. After a qualitative discussion of this issue, we corroborate and extend our results by computing the combined rate of $\\bar{\

  5. Neutrinos from WIMP annihilations

    E-print Network

    Mattias Blennow

    2007-10-08

    We make an improved analysis on the flow of neutrinos originating from WIMP annihilations inside the Sun and the Earth. We treat both neutrino interaction and oscillation effects in a consistent framework. Our numerical simulations are performed in an event based setting, which is useful for both theoretical studies and for creating neutrino telescope Monte Carlos. We find that the flow of muon-type neutrinos is enhanced or suppressed depending on the dominant WIMP annihilation channel.

  6. Geo-neutrino Observation

    SciTech Connect

    Dye, S. T. [University of Hawaii at Manoa, Honolulu, Hawaii 96822 (United States); Hawaii Pacific University, Kaneohe, Hawaii 96744 (United States); Alderman, M.; Batygov, M.; Learned, J. G.; Matsuno, S.; Mahoney, J. M.; Pakvasa, S.; Rosen, M.; Smith, S.; Varner, G. [University of Hawaii at Manoa, Honolulu, Hawaii 96822 (United States); McDonough, W. F. [University of Maryland, College Park, Maryland 20742 (United States)

    2009-12-17

    Observations of geo-neutrinos measure radiogenic heat production within the earth, providing information on the thermal history and dynamic processes of the mantle. Two detectors currently observe geo-neutrinos from underground locations. Other detection projects in various stages of development include a deep ocean observatory. This paper presents the current status of geo-neutrino observation and describes the scientific capabilities of the deep ocean observatory, with emphasis on geology and neutrino physics.

  7. THE PHYSICS OF ELEMENTARY PARTICLES AND FIELDS: Parameterization for Neutrino Mixing Matrix with Deviated Unitarity

    NASA Astrophysics Data System (ADS)

    Lu, Lei; Wang, Wen-Yu; Xiong, Zhao-Hua

    2009-08-01

    Neutrino oscillation experiments provide the first evidence on non-zero neutrino masses and indicate new physics beyond the standard model. With Majorana neutrinos introduced to acquire tiny neutrino masses, it leads to the existence of more than three neutrino species, implying that the ordinary neutrino mixing matrix is only a part of the whole extended unitary mixing matrix and thus no longer unitary. We give a parameterization for a non-unitary neutrino mixing matrix under seesaw framework and further present a method to test the unitarity of the ordinary neutrino mixing matrix.

  8. The Neutrino World

    NASA Astrophysics Data System (ADS)

    Kayser, Boris

    2006-04-01

    The discovery of neutrino mass has raised very interesting questions about the neutrinos and their connections to the rest of physics and astrophysics. We will discuss these questions and the ideas for answering them through future experiments. Ultimately, one would like to discover the origin of neutrino mass. We will discuss some speculations on this origin.

  9. The sudbury neutrino observatory

    Microsoft Academic Search

    Lesko

    1995-01-01

    The solar neutrino problem has been the focus of four major experiments during the past several decades. The Homestake Mine, SAGE and GALLEX experiments rely on radiochemical observation of a small number of neutrino generated atoms. Kamiokande revolutionized the observation of solar neutrinos by developing a real-time water Cerenkov detector. Recently, the calibration of the GALLEX experiment by a man-made

  10. Double Chooz neutrino experiment

    Microsoft Academic Search

    Carmen Palomares

    2009-01-01

    The Double Chooz experiment will use the electron antineutrinos produced by the Chooz nuclear power station to search for a non-vanishing value of the Theta_13 neutrino mixing angle. Double Chooz will be the first of a new generation of neutrino experiments using identical detectors at different distances from the neutrino source to reduce the systematic errors due to the uncertainties

  11. Neutrinos as cosmic messengers

    NASA Astrophysics Data System (ADS)

    Valle, J. W. F.

    2009-04-01

    I briefly review the current status of neutrino oscillation parameters and discuss the role of neutrinos as cosmological probes, that could possibly induce the baryon asymmetry as well as the dark matter in the Universe. I comment on the origin of neutrino masses in seesaw-type and low-scale models and mention some of their laboratory signals.

  12. Neutrino Astronomy Scott Wilbur

    E-print Network

    Golwala, Sunil

    V protons, which should be created with neutrinos, have been seen Can be used to observe possible dark Particle Physics Extremely long baseline for neutrino oscillation studies Dark Matter Searches Many dark Detector Picture from AMANDA II Web Site: http://www.amanda.uci.edu #12;Advantages of Neutrino Astronomy

  13. Neutrino observations from the Sudbury Neutrino Observatory

    SciTech Connect

    Ahmad, Q.R.; Allen, R.C.; Andersen, T.C.; Anglin, J.D.; Barton,J.C.; Beier, E.W.; Bercovitch, M.; Bigu, J.; Biller, S.D.; Black, R.A.; Blevis, I.; Boardman, R.J.; Boger, J.; Bonvin, E.; Boulay, M.G.; Bowler,M.G.; Bowles, T.J.; Brice, S.J.; Browne, M.C.; Bullard, T.V.; Buhler, G.; Cameron, J.; Chan, Y.D.; Chen, H.H.; Chen, M.; Chen, X.; Cleveland, B.T.; Clifford, E.T.H.; Cowan, J.H.M.; Cowen, D.F.; Cox, G.A.; Dai, X.; Dalnoki-Veress, F.; Davidson, W.F.; Doe, P.J.; Doucas, G.; Dragowsky,M.R.; Duba, C.A.; Duncan, F.A.; Dunford, M.; Dunmore, J.A.; Earle, E.D.; Elliott, S.R.; Evans, H.C.; Ewan, G.T.; Farine, J.; Fergani, H.; Ferraris, A.P.; Ford, R.J.; Formaggio, J.A.; Fowler, M.M.; Frame, K.; Frank, E.D.; Frati, W.; Gagnon, N.; Germani, J.V.; Gil, S.; Graham, K.; Grant, D.R.; Hahn, R.L.; Hallin, A.L.; Hallman, E.D.; Hamer, A.S.; Hamian, A.A.; Handler, W.B.; Haq, R.U.; Hargrove, C.K.; Harvey, P.J.; Hazama, R.; Heeger, K.M.; Heintzelman, W.J.; Heise, J.; Helmer, R.L.; Hepburn, J.D.; Heron, H.; Hewett, J.; Hime, A.; Hykawy, J.G.; Isaac,M.C.P.; Jagam, P.; Jelley, N.A.; Jillings, C.; Jonkmans, G.; Kazkaz, K.; Keener, P.T.; Klein, J.R.; Knox, A.B.; Komar, R.J.; Kouzes, R.; Kutter,T.; Kyba, C.C.M.; Law, J.; Lawson, I.T.; Lay, M.; Lee, H.W.; Lesko, K.T.; Leslie, J.R.; Levine, I.; Locke, W.; Luoma, S.; Lyon, J.; Majerus, S.; Mak, H.B.; Maneira, J.; Manor, J.; Marino, A.D.; McCauley, N.; McDonald,D.S.; McDonald, A.B.; McFarlane, K.; McGregor, G.; Meijer, R.; Mifflin,C.; Miller, G.G.; Milton, G.; Moffat, B.A.; Moorhead, M.; Nally, C.W.; Neubauer, M.S.; Newcomer, F.M.; Ng, H.S.; Noble, A.J.; Norman, E.B.; Novikov, V.M.; O'Neill, M.; Okada, C.E.; Ollerhead, R.W.; Omori, M.; Orrell, J.L.; Oser, S.M.; Poon, A.W.P.; Radcliffe, T.J.; Roberge, A.; Robertson, B.C.; Robertson, R.G.H.; Rosendahl, S.S.E.; Rowley, J.K.; Rusu, V.L.; Saettler, E.; Schaffer, K.K.; Schwendener,M.H.; Schulke, A.; Seifert, H.; Shatkay, M.; Simpson, J.J.; Sims, C.J.; et al.

    2001-09-24

    The Sudbury Neutrino Observatory (SNO) is a water imaging Cherenkov detector. Its usage of 1000 metric tons of D{sub 2}O as target allows the SNO detector to make a solar-model independent test of the neutrino oscillation hypothesis by simultaneously measuring the solar {nu}{sub e} flux and the total flux of all active neutrino species. Solar neutrinos from the decay of {sup 8}B have been detected at SNO by the charged-current (CC) interaction on the deuteron and by the elastic scattering (ES) of electrons. While the CC reaction is sensitive exclusively to {nu}{sub e}, the ES reaction also has a small sensitivity to {nu}{sub {mu}} and {nu}{sub {tau}}. In this paper, recent solar neutrino results from the SNO experiment are presented. It is demonstrated that the solar flux from {sup 8}B decay as measured from the ES reaction rate under the no-oscillation assumption is consistent with the high precision ES measurement by the Super-Kamiokande experiment. The {nu}{sub e} flux deduced from the CC reaction rate in SNO differs from the Super-Kamiokande ES results by 3.3{sigma}. This is evidence for an active neutrino component, in additional to {nu}{sub e}, in the solar neutrino flux. These results also allow the first experimental determination of the total active {sup 8}B neutrino flux from the Sun, and is found to be in good agreement with solar model predictions.

  14. Constraining Sterile Neutrinos Using Reactor Neutrino Experiments

    E-print Network

    Ivan Girardi; Davide Meloni; Tommy Ohlsson; He Zhang; Shun Zhou

    2014-08-21

    Models of neutrino mixing involving one or more sterile neutrinos have resurrected their importance in the light of recent cosmological data. In this case, reactor antineutrino experiments offer an ideal place to look for signatures of sterile neutrinos due to their impact on neutrino flavor transitions. In this work, we show that the high-precision data of the Daya Bay experi\\-ment constrain the 3+1 neutrino scenario imposing upper bounds on the relevant active-sterile mixing angle $\\sin^2 2 \\theta_{14} \\lesssim 0.06$ at 3$\\sigma$ confidence level for the mass-squared difference $\\Delta m^2_{41}$ in the range $(10^{-3},10^{-1}) \\, {\\rm eV^2}$. The latter bound can be improved by six years of running of the JUNO experiment, $\\sin^22\\theta_{14} \\lesssim 0.016$, although in the smaller mass range $ \\Delta m^2_{41} \\in (10^{-4} ,10^{-3}) \\, {\\rm eV}^2$. We have also investigated the impact of sterile neutrinos on precision measurements of the standard neutrino oscillation parameters $\\theta_{13}$ and $\\Delta m^2_{31}$ (at Daya Bay and JUNO), $\\theta_{12}$ and $\\Delta m^2_{21}$ (at JUNO), and most importantly, the neutrino mass hierarchy (at JUNO). We find that, except for the obvious situation where $\\Delta m^2_{41}\\sim \\Delta m^2_{31}$, sterile states do not affect these measurements substantially.

  15. Measuring the neutrino mass using intense photon and neutrino beams

    SciTech Connect

    Dicus, Duane A.; Repko, Wayne W.; Vega, Roberto

    2000-11-01

    We compute the cross section for neutrino-photon scattering taking into account a neutrino mass. We explore the possibility of using intense neutrino beams, such as those available at proposed muon colliders, together with high powered lasers to probe the neutrino mass in photon-neutrino collisions.

  16. Weighing the neutrino

    NASA Astrophysics Data System (ADS)

    Jentschura, U. D.; Horváth, D.; Nagy, S.; Nándori, I.; Trócsányi, Z.; Ujvári, B.

    2014-02-01

    We investigate the potential of short-baseline experiments in order to measure the dispersion relation of the (muon) neutrino, with a prospect of eventually measuring the neutrino mass. As a byproduct, the experiment would help to constrain parameters of Lorentz-violating effects in the neutrino sector. The potential of a high-flux laser-accelerated proton beam (e.g., at the upcoming ELI facility), incident on a thick target composed of a light element to produce pions, with a subsequent decay to muons and muon-neutrinos, is discussed. We find a possibility for a muon neutrino mass measurement of unprecedented accuracy.

  17. The Sudbury Neutrino Observatory

    NASA Astrophysics Data System (ADS)

    Boger, J.; Hahn, R. L.; Rowley, J. K.; Carter, A. L.; Hollebone, B.; Kessler, D.; Blevis, I.; Dalnoki-Veress, F.; DeKok, A.; Farine, J.; Grant, D. R.; Hargrove, C. K.; Laberge, G.; Levine, I.; McFarlane, K.; Mes, H.; Noble, A. T.; Novikov, V. M.; O'Neill, M.; Shatkay, M.; Shewchuk, C.; Sinclair, D.; Clifford, E. T. H.; Deal, R.; Earle, E. D.; Gaudette, E.; Milton, G.; Sur, B.; Bigu, J.; Cowan, J. H. M.; Cluff, D. L.; Hallman, E. D.; Haq, R. U.; Hewett, J.; Hykawy, J. G.; Jonkmans, G.; Michaud, R.; Roberge, A.; Roberts, J.; Saettler, E.; Schwendener, M. H.; Seifert, H.; Sweezey, D.; Tafirout, R.; Virtue, C. J.; Beck, D. N.; Chan, Y. D.; Chen, X.; Dragowsky, M. R.; Dycus, F. W.; Gonzalez, J.; Isaac, M. C. P.; Kajiyama, Y.; Koehler, G. W.; Lesko, K. T.; Moebus, M. C.; Norman, E. B.; Okada, C. E.; Poon, A. W. P.; Purgalis, P.; Schuelke, A.; Smith, A. R.; Stokstad, R. G.; Turner, S.; Zlimen, I.; Anaya, J. M.; Bowles, T. J.; Brice, S. J.; Esch, E.-I.; Fowler, M. M.; Goldschmidt, A.; Hime, A.; McGirt, A. F.; Miller, G. G.; Teasdale, W. A.; Wilhelmy, J. B.; Wouters, J. M.; Anglin, J. D.; Bercovitch, M.; Davidson, W. F.; Storey, R. S.; Biller, S.; Black, R. A.; Boardman, R. J.; Bowler, M. G.; Cameron, J.; Cleveland, B.; Ferraris, A. P.; Doucas, G.; Heron, H.; Howard, C.; Jelley, N. A.; Knox, A. B.; Lay, M.; Locke, W.; Lyon, J.; Majerus, S.; Moorhead, M.; Omori, M.; Tanner, N. W.; Taplin, R. K.; Thorman, M.; Wark, D. L.; West, N.; Barton, J. C.; Trent, P. T.; Kouzes, R.; Lowry, M. M.; Bell, A. L.; Bonvin, E.; Boulay, M.; Dayon, M.; Duncan, F.; Erhardt, L. S.; Evans, H. C.; Ewan, G. T.; Ford, R.; Hallin, A.; Hamer, A.; Hart, P. M.; Harvey, P. J.; Haslip, D.; Hearns, C. A. W.; Heaton, R.; Hepburn, J. D.; Jillings, C. J.; Korpach, E. P.; Lee, H. W.; Leslie, J. R.; Liu, M.-Q.; Mak, H. B.; McDonald, A. B.; MacArthur, J. D.; McLatchie, W.; Moffat, B. A.; Noel, S.; Radcliffe, T. J.; Robertson, B. C.; Skensved, P.; Stevenson, R. L.; Zhu, X.; Gil, S.; Heise, J.; Helmer, R. L.; Komar, R. J.; Nally, C. W.; Ng, H. S.; Waltham, C. E.; Allen, R. C.; Bühler, G.; Chen, H. H.; Aardsma, G.; Andersen, T.; Cameron, K.; Chon, M. C.; Hanson, R. H.; Jagam, P.; Karn, J.; Law, J.; Ollerhead, R. W.; Simpson, J. J.; Tagg, N.; Wang, J.-X.; Alexander, C.; Beier, E. W.; Cook, J. C.; Cowen, D. F.; Frank, E. D.; Frati, W.; Keener, P. T.; Klein, J. R.; Mayers, G.; McDonald, D. S.; Neubauer, M. S.; Newcomer, F. M.; Pearce, R. J.; de Water, R. G. V.; Berg, R. V.; Wittich, P.; Ahmad, Q. R.; Beck, J. M.; Browne, M. C.; Burritt, T. H.; Doe, P. J.; Duba, C. A.; Elliott, S. R.; Franklin, J. E.; Germani, J. V.; Green, P.; Hamian, A. A.; Heeger, K. M.; Howe, M.; Drees, R. M.; Myers, A.; Robertson, R. G. H.; Smith, M. W. E.; Steiger, T. D.; Wechel, T. V.; Wilkerson, J. F.

    2000-07-01

    The Sudbury Neutrino Observatory is a second-generation water Cherenkov detector designed to determine whether the currently observed solar neutrino deficit is a result of neutrino oscillations. The detector is unique in its use of D2O as a detection medium, permitting it to make a solar model-independent test of the neutrino oscillation hypothesis by comparison of the charged- and neutral-current interaction rates. In this paper the physical properties, construction, and preliminary operation of the Sudbury Neutrino Observatory are described. Data and predicted operating parameters are provided whenever possible.

  18. Quasidegenerate neutrinos in type II seesaw models

    NASA Astrophysics Data System (ADS)

    Das, Mrinal Kumar; Borah, Debasish; Mishra, Rinku

    2012-11-01

    We present an analysis of normal and inverted hierarchical neutrino mass models within the framework of tri-bimaximal mixing. Considering the neutrinos to be quasidegenerate (QDN), we study two different neutrino mass models with mass eigenvalues (m1,-m2,m3) and (m1,m2,m3) for both normal hierarchical and inverted hierarchical cases. Parameterizing the neutrino mass matrix using best-fit oscillation and cosmology data for a QDN scenario, we find the right-handed Majorana mass matrix using the type I seesaw formula for two types of Dirac neutrino mass matrices: charged lepton type and up quark type. Incorporating the presence of the type II seesaw term which arises naturally in generic left-right symmetric models along with the type I term, we compare the predictions for neutrino mass parameters with the experimental values. Within such a framework and incorporating both oscillation as well as cosmology data, we show that a QDN scenario of neutrino masses can still survive in nature with some minor exceptions. A viable extension of the standard model with an Abelian-gauged flavor symmetry is briefly discussed which can give rise to the desired structure of the Dirac and Majorana mass matrices.

  19. Resonant spin-flavour precession of neutrinos and pulsar velocities

    E-print Network

    E. Kh. Akhmedov; A. Lanza; D. W. Sciama

    1998-03-04

    Young pulsars are known to exhibit large space velocities, up to $10^3$ km/s. We propose a new mechanism for the generation of these large velocities based on an asymmetric emission of neutrinos during the supernova explosion. The mechanism involves the resonant spin-flavour precession of neutrinos with a transition magnetic moment in the magnetic field of the supernova. The asymmetric emission of neutrinos is due to the distortion of the resonance surface by matter polarisation effects in the supernova magnetic field. The requisite values of the field strengths and neutrino parameters are estimated for various neutrino conversions caused by their Dirac or Majorana-type transition magnetic moments.

  20. Update on atmospheric neutrinos

    SciTech Connect

    Gonzalez-Garcia, M.C.; Nunokawa, H.; Peres, O.L.; Valle, J.W. [Departament de Fisica Teorica, Instituto de Fisica Corpuscular---C.S.I.C., Universitat de Valencia 46100 Burjassot, Valencia (Spain)] [Departament de Fisica Teorica, Instituto de Fisica Corpuscular---C.S.I.C., Universitat de Valencia 46100 Burjassot, Valencia (Spain); Gonzalez-Garcia, M.C. [Instituto de Fisica Teorica, Universidade Estadual Paulista, Rua Pamplona 145, 01405-900 Sao Paulo (Brazil)] [Instituto de Fisica Teorica, Universidade Estadual Paulista, Rua Pamplona 145, 01405-900 Sao Paulo (Brazil); Stanev, T. [Bartol Research Institute, University of Delaware, Newark, Delaware 19716 (United States)] [Bartol Research Institute, University of Delaware, Newark, Delaware 19716 (United States)

    1998-08-01

    We discuss the impact of recent experimental results on the determination of atmospheric neutrino oscillation parameters. We use all published results on atmospheric neutrinos, including the preliminary large statistics data of Super-Kamiokande. We reanalyze the data in terms of both {nu}{sub {mu}}{r_arrow}{nu}{sub {tau}} and {nu}{sub {mu}}{r_arrow}{nu}{sub e} channels using new improved calculations of the atmospheric neutrino flux. We compare the sensitivity attained in atmospheric neutrino experiments with those of accelerator and reactor neutrino oscillation searches, including the recent CHOOZ experiment. We briefly comment on the implications of atmospheric neutrino data in relation to future searches for neutrino oscillations with long baselines, such as the K2K, MINOS, ICARUS, and NOE experiments. {copyright} {ital 1998} {ital The American Physical Society}

  1. Absolute neutrino mass scale

    NASA Astrophysics Data System (ADS)

    Capelli, Silvia; Di Bari, Pasquale

    2013-04-01

    Neutrino oscillation experiments firmly established non-vanishing neutrino masses, a result that can be regarded as a strong motivation to extend the Standard Model. In spite of being the lightest massive particles, neutrinos likely represent an important bridge to new physics at very high energies and offer new opportunities to address some of the current cosmological puzzles, such as the matter-antimatter asymmetry of the Universe and Dark Matter. In this context, the determination of the absolute neutrino mass scale is a key issue within modern High Energy Physics. The talks in this parallel session well describe the current exciting experimental activity aiming to determining the absolute neutrino mass scale and offer an overview of a few models beyond the Standard Model that have been proposed in order to explain the neutrino masses giving a prediction for the absolute neutrino mass scale and solving the cosmological puzzles.

  2. Scalar sextet in the 331 model with right-handed neutrinos

    SciTech Connect

    Nguyen Anh Ky; Nguyen Thi Hong Van [Institute of Physics and Electronics, 10 Dao Tan, Hanoi (Viet Nam)

    2005-12-01

    A Higgs sextet is introduced in order to generate Dirac and Majorana neutrino masses in the 331 model with right-handed neutrinos. As will be seen the present sextet introduction leads to a rich neutrino mass structure. The smallness of neutrino masses can be achieved via, for example, a seesaw limit. The fact that the masses of the charged leptons are not effected by their new Yukawa couplings to the sextet is convenient for generating small neutrino masses.

  3. Atmospheric Neutrinos: Background and Signal

    SciTech Connect

    Mocioiu, Irina [Department of Physics, Pennsylvania State University, 104 Davey Lab 122, University Park, PA 16802 (United States)

    2010-11-24

    We discuss a brief history of atmospheric neutrinos, from background to proton decay searches to proving neutrino oscillations. We then discuss how high statistics atmospheric neutrino measurements in the IceCube Deep Core Array can provide useful information about neutrino oscillation parameters and other neutrino properties.

  4. Cosmological constraints on neutrino degeneracy

    Microsoft Academic Search

    Kang Ho-Shik; Gary Steigman

    1992-01-01

    A large lepton asymmetry may be hidden in degenerate neutrinos. The cosmological consequences of neutrino degeneracy are explored with particular attention to the effects on primordial nucleosynthesis. Degenerate neutrinos will increase the density and expansion rate of the Universe so that cosmological data provides constraints on neutrino degeneracy. Although degenerate big-bang nucleosynthesis (DBBN) has two more free parameters (the electron-neutrino

  5. Properties of neutrinos: Recent results

    SciTech Connect

    Robertson, R.G.H.

    1987-01-01

    Recent progress in experimental determinations of the properties of neutrinos is summarized. In particular, the extensive work on direct kinematic measurements of neutrino mass, on neutrino counting and on neutrino oscillations is highlighted. It is concluded that there may already be sufficient information to fix the masses of the neutrinos, but the evidence is still far from convincing. 63 refs., 13 figs.

  6. High Energy Neutrino Astronomy and Neutrino Telescopes

    NASA Astrophysics Data System (ADS)

    Kouchner, A.

    2015-04-01

    Neutrinos constitute a unique probe since they escape from their sources, travel undisturbed on cosmological distances and are produced in high-energy (HE) hadronic processes. In particular they would allow a direct detection and unambiguous identification of the acceleration sites of HE baryonic cosmic rays (CR), which remain unknown. Recent results from the ICECUBE collaboration present the first highly significant indication for the detection of high-energy extraterrestrial neutrinos, after several decades of instrumental efforts. We briefly report on this important results which open the route for the high-energy neutrino astronomy era. We then focus on the ANTARES detector, which despite its modest size with respect to ICECUBE is the largest deep-sea neutrino telescope in the world. The primary goal is to search for astrophysical neutrinos in the TeV-PeV range. This comprises generic searches for any diffuse cosmic neutrino flux as well as more specific searches for astrophysical sources such as active galactic nuclei or Galactic sources. The search program also includes multi-messenger analyses based on time and/or space coincidences with other cosmic probes. The ANTARES observatory is sensitive to a wide-range of other phenomena, from atmospheric neutrino oscillations to dark matter annihilation or potential exotics such as nuclearites and magnetic monopoles. The most recent results are reported.

  7. Neutrinoless double beta decay with pseudo Dirac neutrinos

    Microsoft Academic Search

    Pei-Hong Gu

    2011-01-01

    The lepton number violation for neutrinoless double beta decay may only have a negligible effect on the neutrino mass generation. In this case the neutrinoless double beta decay can not verify the Majorana nature of neutrinos even if it is confirmed in the future. For illustration we propose a model to realize a significant neutrinoless double beta decay with pseudo

  8. Neutrino factory near detector

    NASA Astrophysics Data System (ADS)

    Bogomilov, M.; Karadzhov, Y.; Matev, R.; Tsenov, R.; Laing, A.; Soler, F. J. P.

    2013-08-01

    The neutrino factory is a facility for future precision studies of neutrino oscillations. A so-called near detector is essential for reaching the required precision for a neutrino oscillation analysis. The main task of the near detector is to measure the flux of the neutrino beam. Such a high intensity neutrino source like a neutrino factory provides also the opportunity for precision studies of various neutrino interaction processes in the near detector. We discuss the design concepts of such a detector. Results of simulations of a high resolution scintillating fiber tracker show that such a detector is capable of determining the neutrino flux normalization with an uncertainty of less than 1% by measuring pure leptonic interactions. Reconstruction of the neutrino energy in each event and a flux estimation based on the shapes of the neutrino energy spectra are discussed. A full setup of the near detector, consisting of a high granularity vertex detector, high resolution tracker, and muon catcher is also presented. Finally, a method to extrapolate the measured near detector flux to the far detector is shown, demonstrating that it is able to extract the correct values of ?13 and the CP violation phase ? without any significant bias and with high accuracy.

  9. Limits on cold dark matter from underground neutrinos

    NASA Astrophysics Data System (ADS)

    Losecco, J. M.

    1995-02-01

    Limits on the flux of energetic neutrinos from the direction of the Sun are used to improve the limits on cold dark matter. The model of Olive and Srednicki is used to exclude a number of dark matter candidates including photinos, Higgsinos, Majorana neutrinos, massive Dirac neutrinos and sneutrinos. New limits are placed on photino and Higgsino masses. We also quote limits on fluxes from the Earth.

  10. Acquiring information about neutrino parameters by detecting supernova neutrinos

    SciTech Connect

    Huang, Ming-Yang; Guo, Xin-Heng [College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Young, Bing-Lin [Department of Physics and Astronomy, Iowa State University, Ames, Iowa 5001 (United States); Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190 (China)

    2010-08-01

    We consider the supernova shock effects, the Mikheyev-Smirnov-Wolfenstein effects, the collective effects, and the Earth matter effects in the detection of type II supernova neutrinos on the Earth. It is found that the event number of supernova neutrinos depends on the neutrino mass hierarchy, the neutrino mixing angle {theta}{sub 13}, and neutrino masses. Therefore, we propose possible methods to identify the mass hierarchy and acquire information about {theta}{sub 13} and neutrino masses by detecting supernova neutrinos. We apply these methods to some current neutrino experiments.

  11. Testing the Bimodal/Schizophrenic Neutrino Hypothesis in Neutrinoless Double Beta Decay and Neutrino Telescopes

    E-print Network

    James Barry; Rabindra N. Mohapatra; Werner Rodejohann

    2011-06-27

    The standard assumption is that all three neutrino mass states are either Dirac or Majorana. However, it was recently suggested by Allaverdi, Dutta and one of the authors (R.N.M.) that mixed, or bimodal, flavor neutrino scenarios are conceivable and are consistent with all known observations (these were called "schizophrenic" in the ADM paper). In that case each individual mass eigenstate can be either Dirac or Majorana, so that the flavor eigenstates are "large" admixtures of both. An example of this "bimodal" situation is to consider one mass state as a Dirac particle (with a sterile partner), while the other two are of Majorana type. Since only Majorana particles contribute to neutrinoless double beta decay, the usual dependence of this observable on the neutrino mass is modified within this scenario. We study this in detail and, in particular, generalize the idea for all possible bimodal combinations. Inevitably, radiative corrections will induce a pseudo-Dirac nature to the Dirac states at the one-loop level, and the effects of the pseudo-Dirac mass splitting will show up in the flavor ratios of neutrinos from distant cosmological sources. Comparison of the effective mass in neutrinoless double beta decay as well as flavor ratios at neutrino telescopes, for different pseudo-Dirac cases and with their usual phenomenology, can distinguish the different bimodal possibilities.

  12. Solar neutrino detection

    SciTech Connect

    Miramonti, Lino [Physics department of Milano University and INFN (Italy)

    2009-04-30

    More than 40 years ago, neutrinos where conceived as a way to test the validity of the solar models which tell us that stars are powered by nuclear fusion reactions. The first measurement of the neutrino flux, in 1968 in the Homestake mine in South Dakota, detected only one third of the expected value, originating what has been known as the Solar Neutrino Problem. Different experiments were built in order to understand the origin of this discrepancy. Now we know that neutrinos undergo oscillation phenomenon changing their nature traveling from the core of the Sun to our detectors. In the work the 40 year long saga of the neutrino detection is presented; from the first proposals to test the solar models to last real time measurements of the low energy part of the neutrino spectrum.

  13. Solar neutrino detection

    E-print Network

    Lino Miramonti

    2009-01-22

    More than 40 years ago, neutrinos where conceived as a way to test the validity of the solar models which tell us that stars are powered by nuclear fusion reactions. The first measurement of the neutrino flux, in 1968 in the Homestake mine in South Dakota, detected only one third of the expected value, originating what has been known as the Solar Neutrino Problem. Different experiments were built in order to understand the origin of this discrepancy. Now we know that neutrinos undergo oscillation phenomenon changing their nature traveling from the core of the Sun to our detectors. In the work the 40 year long saga of the neutrino detection is presented; from the first proposals to test the solar models to last real time measurements of the low energy part of the neutrino spectrum.

  14. Neutrinos and Collider Physics

    E-print Network

    Frank F. Deppisch; P. S. Bhupal Dev; Apostolos Pilaftsis

    2015-03-09

    We review the collider phenomenology of neutrino physics and the synergetic aspects at energy, intensity and cosmic frontiers to test the new physics behind the neutrino mass mechanism. In particular, we focus on seesaw models within the minimal setup as well as with extended gauge and/or Higgs sectors, and on supersymmetric neutrino mass models with seesaw mechanism and with $R$-parity violation. In the simplest Type-I seesaw scenario with sterile neutrinos, we summarize and update the current experimental constraints on the sterile neutrino mass and its mixing with the active neutrinos. We also discuss the future experimental prospects of testing the seesaw mechanism at colliders and in related low-energy searches for rare processes, such as lepton flavor violation and neutrinoless double beta decay. The implications of the discovery of lepton number violation at the LHC for leptogenesis are also studied.

  15. Light WIMPs and Equivalent Neutrinos

    NASA Astrophysics Data System (ADS)

    Steigman, Gary; Nollett, Kenneth M.

    Very light WIMPs (?), thermal relics that annihilate late in the early Universe, change the energy and entropy densities at BBN and at recombination. BBN, in combination with the CMB, can remove some of the degeneracies among light WIMPs and equivalent neutrinos, constraining the existence and properties of each. Depending on the nature of the light WIMP (Majorana or Dirac fermion, real or complex scalar) the joint BBN + CMB analyses set lower bounds to m? in the range 0.5 - 5 MeV (m?/me ?1 - 10), and they identify best fit values for m? in the range 5 - 10 MeV. The joint BBN + CMB analysis finds a best fit value for the number of equivalent neutrinos, ?N? ? 0.65, nearly independent of the nature of the WIMP. In the absence of a light WIMP (m? ?20 MeV), Neff = 3.05(1 + ?N?/3). In this case, there is excellent agreement between BBN and the CMB, but the joint fit reveals ?N? = 0.40 ± 0.17, disfavoring standard big bang nucleosynthesis (SBBN) (?N? = 0) at ? 2.4 ?, as well as a sterile neutrino (?N? = 1) at ? 3.5 ?. The best BBN + CMB joint fit disfavors the absence of dark radiation (?N? = 0 at ? 95% confidence), while allowing for the presence of a sterile neutrino (?N? = 1 at ?1 ?). For all cases considered here, the lithium problem persists. These results, presented at the TAUP 2013 Conference, are based on Nollett & Steigman [14].

  16. Novel Ideas for Neutrino Beams

    SciTech Connect

    Peach, Ken [John Adams Institute for Accelerator Science, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Royal Holloway University of London, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom)

    2007-04-23

    Recent developments in neutrino physics, primarily the demonstration of neutrino oscillations in both atmospheric neutrinos and solar neutrinos, provide the first conclusive evidence for physics beyond the Standard Model of particle physics. The simplest phenomenology of neutrino oscillations, for three generations of neutrino, requires six parameters - two squared mass differences, 3 mixing angles and a complex phase that could, if not 0 or {pi}, contribute to the otherwise unexplained baryon asymmetry observed in the universe. Exploring the neutrino sector will require very intense beams of neutrinos, and will need novel solutions.

  17. Neutrino oscillation studies with reactors.

    PubMed

    Vogel, P; Wen, L J; Zhang, C

    2015-01-01

    Nuclear reactors are one of the most intense, pure, controllable, cost-effective and well-understood sources of neutrinos. Reactors have played a major role in the study of neutrino oscillations, a phenomenon that indicates that neutrinos have mass and that neutrino flavours are quantum mechanical mixtures. Over the past several decades, reactors were used in the discovery of neutrinos, were crucial in solving the solar neutrino puzzle, and allowed the determination of the smallest mixing angle ?13. In the near future, reactors will help to determine the neutrino mass hierarchy and to solve the puzzling issue of sterile neutrinos. PMID:25913819

  18. Accelerator neutrino program at Fermilab

    SciTech Connect

    Parke, Stephen J.; /Fermilab

    2010-05-01

    The accelerator neutrino programme in the USA consists primarily of the Fermilab neutrino programme. Currently, Fermilab operates two neutrino beamlines, the Booster neutrino beamline and the NuMI neutrino beamline and is the planning stages for a third neutrino beam to send neutrinos to DUSEL. The experiments in the Booster neutrino beamline are miniBooNE, SciBooNE and in the future microBooNE, whereas in the NuMI beamline we have MINOS, ArgoNut, MINERVA and coming soon NOvA. The major experiment in the beamline to DUSEL will be LBNE.

  19. Neutrino Oscillation Studies with Reactors

    E-print Network

    Vogel, Petr; Zhang, Chao

    2015-01-01

    Nuclear reactors are one of the most intense, pure, controllable, cost-effective, and well-understood sources of neutrinos. Reactors have played a major role in the study of neutrino oscillations, a phenomenon that indicates that neutrinos have mass and that neutrino flavors are quantum mechanical mixtures. Over the past several decades reactors were used in the discovery of neutrinos, were crucial in solving the solar neutrino puzzle, and allowed the determination of the smallest mixing angle $\\theta_{13}$. In the near future, reactors will help to determine the neutrino mass hierarchy and to solve the puzzling issue of sterile neutrinos.

  20. Neutrino Oscillation Studies with Reactors

    E-print Network

    Petr Vogel; Liangjian Wen; Chao Zhang

    2015-04-27

    Nuclear reactors are one of the most intense, pure, controllable, cost-effective, and well-understood sources of neutrinos. Reactors have played a major role in the study of neutrino oscillations, a phenomenon that indicates that neutrinos have mass and that neutrino flavors are quantum mechanical mixtures. Over the past several decades reactors were used in the discovery of neutrinos, were crucial in solving the solar neutrino puzzle, and allowed the determination of the smallest mixing angle $\\theta_{13}$. In the near future, reactors will help to determine the neutrino mass hierarchy and to solve the puzzling issue of sterile neutrinos.

  1. Neutrino oscillation studies with reactors

    NASA Astrophysics Data System (ADS)

    Vogel, P.; Wen, L. J.; Zhang, C.

    2015-04-01

    Nuclear reactors are one of the most intense, pure, controllable, cost-effective and well-understood sources of neutrinos. Reactors have played a major role in the study of neutrino oscillations, a phenomenon that indicates that neutrinos have mass and that neutrino flavours are quantum mechanical mixtures. Over the past several decades, reactors were used in the discovery of neutrinos, were crucial in solving the solar neutrino puzzle, and allowed the determination of the smallest mixing angle ?13. In the near future, reactors will help to determine the neutrino mass hierarchy and to solve the puzzling issue of sterile neutrinos.

  2. Neutrino oscillation studies with reactors

    PubMed Central

    Vogel, P.; Wen, L.J.; Zhang, C.

    2015-01-01

    Nuclear reactors are one of the most intense, pure, controllable, cost-effective and well-understood sources of neutrinos. Reactors have played a major role in the study of neutrino oscillations, a phenomenon that indicates that neutrinos have mass and that neutrino flavours are quantum mechanical mixtures. Over the past several decades, reactors were used in the discovery of neutrinos, were crucial in solving the solar neutrino puzzle, and allowed the determination of the smallest mixing angle ?13. In the near future, reactors will help to determine the neutrino mass hierarchy and to solve the puzzling issue of sterile neutrinos. PMID:25913819

  3. Neutrinos in Cosmology

    SciTech Connect

    Wong, Yvonne Y. Y. [Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut) Foehringer Ring 6, 80805 Munich (Germany)

    2008-01-24

    I give an overview of the effects of neutrinos on cosmology, focussing in particular on the role played by neutrinos in the evolution of cosmological perturbations. I discuss how recent observations of the cosmic microwave background and the large-scale structure of galaxies can probe neutrino masses with greater precision than current laboratory experiments. I describe several new techniques that will be used to probe cosmology in the future.

  4. Neutrinos: Nature's Ghosts?

    ScienceCinema

    Lincoln, Don

    2014-08-12

    Dr. Don Lincoln introduces one of the most fascinating inhabitants of the subatomic realm: the neutrino. Neutrinos are ghosts of the microworld, almost not interacting at all. In this video, he describes some of their properties and how they were discovered. Studies of neutrinos are expected to be performed at many laboratories across the world and to form one of the cornerstones of the Fermilab research program for the next decade or more.

  5. Neutrino mixing and discrete symmetries

    NASA Astrophysics Data System (ADS)

    Hu, Bo

    2013-02-01

    In this paper we discuss a new way to derive neutrino mixing patterns, which originates from the idea proposed in a recent article by Hernandez and Smirnov. Its applications to various cases are discussed. We first present the complete set of possible mixing patterns for the minimal case where unbroken residual symmetries of the Majorana neutrino and left-handed charged-lepton mass matrices obey some general assumptions that are also satisfied by many models based on discrete symmetries. We find that they are either well-known mixing patterns or phenomenologically disfavored ones. It shows clearly that, for full-mixing matrices to fit the mixing data with small or negligible corrections, it is necessary to go beyond the minimal scenario. We present an explicit formalism for a rather general nonminimal case. Some applications and phenomenological implications are discussed. Several new mixing patterns are derived.

  6. Solar atmosphere neutrino oscillations

    NASA Astrophysics Data System (ADS)

    Fogli, G. L.; Lisi, E.; Mirizzi, A.; Montanino, D.; Serpico, P. D.

    2007-06-01

    The Sun is a source of high energy neutrinos (E>10 GeV) produced by cosmic ray interactions in the solar atmosphere. We study the impact of three-flavor oscillations on the solar atmosphere neutrino fluxes observable at Earth. We find that peculiar matter oscillation effects in the Sun do exist, but are significantly suppressed by averaging over the production region and over the neutrino and antineutrino components. In particular, the relation between the neutrino fluxes at the Sun and at the Earth can be approximately expressed in terms of phase-averaged “vacuum” oscillations, dominated by a single mixing parameter (the angle ?).

  7. Solar atmosphere neutrino oscillations

    NASA Astrophysics Data System (ADS)

    Fogli, G. L.; Lisi, E.; Mirizzi, A.; Montanino, D.; Serpico, P. D.

    2008-07-01

    The Sun is a source of high energy neutrinos (E > 10 GeV) produced by cosmic ray interactions in the solar atmosphere. We study the impact of three-flavor oscillations on the solar atmosphere neutrino fluxes observable at Earth. We find that peculiar matter oscillation effects in the Sun do exist, but are significantly suppressed by averaging over the production region and over the neutrino and antineutrino components. In particular, the relation between the neutrino fluxes at the Sun and at the Earth can be approximately expressed in terms of phase-averaged 'vacuum' oscillations, dominated by a single mixing parameter (the angle ?23).

  8. Baryogenesis via neutrino oscillations

    E-print Network

    E. Kh. Akhmedov; V. A. Rubakov; A. Yu. Smirnov

    1998-07-29

    We propose a new mechanism of leptogenesis in which the asymmetries in lepton numbers are produced through the CP-violating oscillations of ``sterile'' (electroweak singlet) neutrinos. The asymmetry is communicated from singlet neutrinos to ordinary leptons through their Yukawa couplings. The lepton asymmetry is then reprocessed into baryon asymmetry by electroweak sphalerons. We show that the observed value of baryon asymmetry can be generated in this way, and the masses of ordinary neutrinos induced by the seesaw mechanism are in the astrophysically and cosmologically interesting range. Except for singlet neutrinos, no physics beyond the Standard Model is required.

  9. The sudbury neutrino observatory

    SciTech Connect

    Lesko, K.T. [Lawrence Berkeley Laboratory, CA (United States)

    1995-04-01

    The solar neutrino problem has been the focus of four major experiments during the past several decades. The Homestake Mine, SAGE and GALLEX experiments rely on radiochemical observation of a small number of neutrino generated atoms. Kamiokande revolutionized the observation of solar neutrinos by developing a real-time water Cerenkov detector. Recently, the calibration of the GALLEX experiment by a man-made neutrino source has invigorated interest in this long standing discrepancy between observed neutrino flux and solar models. The next generation of detectors is now under construction. The Sudbury Neutrino Observatory (SNO) is 1000 tonne heavy water Cerenkov detector. The siting of the experiment more than 2000 meters below ground, its enhanced event rate, and the unique neutral current sensitivity of its heavy water target provide SNO with an excellent opportunity to detect neutrino flavor changes. Observation of the spectral shape of the charge current reaction may provide crucial information regarding matter-enhanced neutrino oscillations. The construction of SNO is now well underway. First signals are anticipated in 1996. The solar neutrino problem is reviewed and the outlook for SNO is presented.

  10. Solar atmosphere neutrino oscillations

    SciTech Connect

    Fogli, G.L.; Lisi, E.; Mirizzi, A.; /INFN, Bari; Montanino, D.; /INFN, Lecce; Serpico, P.D.; /Fermilab

    2007-02-01

    The Sun is a source of high energy neutrinos (E > 10 GeV) produced by cosmic ray interactions in the solar atmosphere. We study the impact of three-flavor oscillations on the solar atmosphere neutrino fluxes observable at Earth. We find that peculiar matter oscillation effects in the Sun do exist, but are significantly suppressed by averaging over the production region and over the neutrino and antineutrino components. In particular, the relation between the neutrino fluxes at the Sun and at the Earth can be approximately expressed in terms of phase-averaged ''vacuum'' oscillations, dominated by a single mixing parameter (the angle {theta}{sub 23}).

  11. The Sudbury Neutrino Observatory

    NASA Astrophysics Data System (ADS)

    Simpson, J. J.

    2001-04-01

    The Sudbury Neutrino Observatory (SNO) is a large, underground heavywater Cerenkov detector which has been designed and built primarily to solve the solar neutrino problem, the shortfall in the flux of neutrinos coming from the sun relative to the best solar model predictions. As discussed in previous talks in this symposium, the neutrino flux shortfall occurs in all previous experiments which were sensitive to different energy thresholds for solar neutrinos - the gallium experiments, the chlorine experiment, and the water Cerenkov experiments. And furthermore, the shortfall seems to be a result which is independent of physicallyplausible changes in the standard solar model, changes which are consistent with helioseismological results. Because it seems to be impossible to modify the standard solar model to account for all aspects of the neutrino flux shortfall, the explanation would seem to be connected to properties of neutrinos. The favored explanation, discussed previously in this symposium by Bahcall, is neutrino-flavour oscillations; this explanation has already been successfully invoked to explain the results on atmosphere muon neutrinos obtained by Superamiokande (see H. Sobel, this symposium)...

  12. Molybdenum solar neutrino experiment

    SciTech Connect

    Wolfsberg, K.; Cowan, G.A.; Bryant, E.A.; Daniels, K.S.; Downey, S.W.; Haxton, W.C.; Niesen, V.G.; Nogar, N.S.; Miller, C.M.; Rokop, D.J.

    1984-01-01

    The goal of the molybdenum solar neutrino experiment is to deduce the /sup 8/B solar neutrino flux, averaged over the past several million years, from the concentration of /sup 98/Tc in a deeply buried molybdenum deposit. The experiment is important to an understanding of stellar processes because it will shed light on the reason for the discrepancy between theory and observation of the chlorine solar neutrino experiment. Possible reasons for the discrepancy may lie in the properties of neutrinos (neutrino oscillations or massive neutrinos) or in deficiencies of the standard solar model. The chlorine experiment only measures the /sup 8/B neutrino flux in current times and does not address possible temporal variations in the interior of the sun, which are also not considered in the standard model. In the molybdenum experiment, we plan to measure /sup 98/Tc (4.2 Myr), also produced by /sup 8/B neutrinos, and possibly /sup 97/Tc (2.6 Myr), produced by lower energy neutrinos.

  13. Neutrino Models and Leptogenesis

    E-print Network

    Law, Sandy S C

    2008-01-01

    Neutrino properties can play a crucial role in determining the matter-antimatter asymmetry of the universe if thermal leptogenesis is the correct solution to the baryogenesis problem. Owing to this, the study of neutrino models goes beyond the mere purpose of generating tiny neutrino masses, and it is natural to incorporate the puzzle of the cosmic baryon asymmetry. To this end, we have investigated several different extensions of the neutrino model based on the type I seesaw mechanism with particular emphasis on their leptogenesis implications.

  14. Neutrino Models and Leptogenesis

    E-print Network

    Sandy S. C. Law

    2009-01-09

    Neutrino properties can play a crucial role in determining the matter-antimatter asymmetry of the universe if thermal leptogenesis is the correct solution to the baryogenesis problem. Owing to this, the study of neutrino models goes beyond the mere purpose of generating tiny neutrino masses, and it is natural to incorporate the puzzle of the cosmic baryon asymmetry. To this end, we have investigated several different extensions of the neutrino model based on the type I seesaw mechanism with particular emphasis on their leptogenesis implications.

  15. Status and commissioning of the Karlsruhe tritium neutrino experiment KATRIN

    NASA Astrophysics Data System (ADS)

    Thuemmler, Thomas; Katrin Collaboration

    2013-10-01

    Neutrino properties, and especially the determination of the neutrino rest mass, play an important role at the intersections of cosmology, particle physics and astroparticle physics. At present there are two complementary approaches to address this topic in laboratory experiments. The search for neutrinoless double ? decay probes whether neutrinos are Majorana particles and determines an effective neutrino mass value. Experiments based on single ? decay investigate electrons close to their kinematic endpoint in order to determine the neutrino mass by a modelindependent method. The KArlsruhe TRItium Neutrino experiment (KATRIN) is currently the experiment in the most advanced status of commissioning. Applying an ultra-luminous molecular windowless gaseous tritium source and an integrating high-resolution spectrometer of MAC-E filter type, it allows ? spectroscopy close to the tritium endpoint with unprecedented precision and will reach a sensitivity of 200 meV/c2 (90% C.L.) on the neutrino mass.

  16. Massive neutrinos and invisible axion minimally connected

    NASA Astrophysics Data System (ADS)

    Bertolini, Stefano; Di Luzio, Luca; Kolešová, Helena; Malinský, Michal

    2015-03-01

    We survey a few minimal scalar extensions of the standard electroweak model that provide a simple setup for massive neutrinos in connection with an invisible axion. The presence of a chiral U (1 ) à la Peccei-Quinn drives the pattern of Majorana neutrino masses while providing a dynamical solution to the strong C P problem and an axion as a dark matter candidate. We paradigmatically apply such a renormalizable framework to type-II seesaw and to two viable models for neutrino oscillations where the neutrino masses arise at one and two loops, respectively. We comment on the naturalness of the effective setups as well as on their implications for vacuum stability and electroweak baryogenesis.

  17. High Energy Neutrinos with a Mediterranean Neutrino Telescope

    SciTech Connect

    Borriello, E.; /Naples U. /INFN, Naples /Valencia U., IFIC; Cuoco, A.; /Aarhus U.; Mangano, G.; /Naples U. /INFN, Naples; Miele, G.; /Naples U. /INFN, Naples /Valencia U.,; Pastor, Sergio; /Valencia U., IFIC; Pisanti, O.; /Naples U. /INFN, Naples; Serpico, Pasquale Dario; /Fermilab

    2007-09-01

    The high energy neutrino detection by a km{sup 3} Neutrino Telescope placed in the Mediterranean sea provides a unique tool to both determine the diffuse astrophysical neutrino flux and the neutrino nucleon cross section in the extreme kinematical region, which could unveil the presence of new physics. Here is performed a brief analysis of possible NEMO site performances.

  18. Cosmological neutrino mass detection: The Best probe of neutrino lifetime

    SciTech Connect

    Serpico, Pasquale D.; /Fermilab

    2007-01-01

    Future cosmological data may be sensitive to the effects of a finite sum of neutrino masses even as small as {approx}0.06 eV, the lower limit guaranteed by neutrino oscillation experiments. We show that a cosmological detection of neutrino mass at that level would improve by many orders of magnitude the existing limits on neutrino lifetime, and as a consequence on neutrino secret interactions with (quasi-)massless particles as in majoron models. On the other hand, neutrino decay may provide a way-out to explain a discrepancy {approx}< 0.1 eV between cosmic neutrino bounds and Lab data.

  19. Neutrino Nuclear Responses for Neutrino Studies in Nuclear Femto Laboratories

    SciTech Connect

    Ejiri, Hiroyasu [Research Center for Nuclear Physics, Osaka University, Osaka 567-0047 (Japan); Nuclear Science, Czech Technical University, Brehova, Prague (Czech Republic)

    2010-11-24

    Fundamental properties of neutrinos and neutrino nuclear interactions are of great interest from particle and astro-nuclear physics view points. They are well studied in nuclear femto laboratories, where neutrino nuclear responses are crucial. Neutrino masses and neutrino natures are studied by neutrino-less double beta decays (0{nu}{beta}{beta}) in nuclei. Here neutrino nuclear responses are required to extract neutrino properties from 0{nu}{beta}{beta} rates. Neutrino nuclear responses are sensitive to nuclear spin isospin correlations and nuclear structures. They are experimentally studied by nuclear probes for charge exchange nuclear reactions, photon EM probes for photo-nuclear reactions, and lepton probes for muon and neutrino capture reactions.

  20. Charm physics with neutrinos

    Microsoft Academic Search

    Giovanni De Lellis; Pasquale Migliozzi; Pietro Santorelli

    2004-01-01

    High energy neutrino interactions induce charmed hadron production at the level of a few percent and therefore they constitute a powerful tool to study charm physics. After 30 years of investigations with different neutrino beams and different detection techniques, important results have been achieved while other topics still need to be clarified. Recently, relevant results have been reported by several

  1. Radiochemical solar neutrino experiments

    Microsoft Academic Search

    V. N. Gavrin; B. T. Cleveland

    2007-01-01

    Radiochemical experiments have been crucial to solar neutrino research. Even today, they provide the only direct measurement of the rate of the proton-proton fusion reaction, p + p --> d + e^+ + nu_e, which generates most of the Sun's energy. We first give a little history of radiochemical solar neutrino experiments with emphasis on the gallium experiment SAGE --

  2. Submarine neutrino communication

    Microsoft Academic Search

    Patrick Huber

    2010-01-01

    We discuss the possibility to use a high energy neutrino beam from a muon storage ring to provide one way communication with a submerged submarine. Neutrino interactions produce muons which can be detected either, directly when they pass through the submarine or by their emission of Cerenkov light in sea water, which, in turn, can be exploited with sensitive photo

  3. Neutrinos for Peace

    NASA Astrophysics Data System (ADS)

    Cribier, M.

    2015-04-01

    The fundamental knowledge on neutrinos acquired in the recent years open the possibility of applied neutrino physics. Among it the automatic and non intrusive monitoring of nuclear reactor by its antineutrino signal could be very valuable to IAEA in charge of the control of nuclear power plants. Several efforts worldwide have already started.

  4. Monte Carlo Neutrino Oscillations

    E-print Network

    James P. Kneller; Gail C. McLaughlin

    2005-09-29

    We demonstrate that the effects of matter upon neutrino propagation may be recast as the scattering of the initial neutrino wavefunction. Exchanging the differential, Schrodinger equation for an integral equation for the scattering matrix S permits a Monte Carlo method for the computation of S that removes many of the numerical difficulties associated with direct integration techniques.

  5. Neutrinos -- Going to extremes

    Microsoft Academic Search

    John F. Wilkerson

    2008-01-01

    Like the Southeastern Section of the APS, neutrinos are also septuagenarians, having been ``born'' in 1930 as a means of solving the apparent violation of energy and angular momentum in nuclear beta-decay. Because of their elusive nature, we have had a limited grasp of their intrinsic properties. However, in the past decade our understanding of neutrinos and their role in

  6. Deformation effects and neutrinoless positron {beta}{beta} decay of {sup 96}Ru, {sup 102}Pd, {sup 106}Cd, {sup 124}Xe, {sup 130}Ba, and {sup 156}Dy isotopes within a mechanism involving Majorana neutrino mass

    SciTech Connect

    Rath, P. K. [Department of Physics, University of Lucknow, Lucknow-226007 (India); Chandra, R. [Department of Physics, University of Lucknow, Lucknow-226007 (India); Department of Physics and Meteorology, IIT, Kharagpur-721302 (India); Chaturvedi, K. [Department of Physics, University of Lucknow, Lucknow-226007 (India); Department of Physics, Bundelkhand University, Jhansi-284128 (India); Raina, P. K. [Department of Physics and Meteorology, IIT, Kharagpur-721302 (India); Hirsch, J. G. [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, A.P. 70-543, Mexico 04510 D.F. (Mexico)

    2009-10-15

    The ({beta}{sup +}{beta}{sup +}){sub 0{nu}} and ({epsilon}{beta}{sup +}){sub 0{nu}} modes of {sup 96}Ru, {sup 102}Pd, {sup 106}Cd, {sup 124}Xe, {sup 130}Ba, and {sup 156}Dy isotopes are studied in the projected Hartree-Fock-Bogoliubov framework for the 0{sup +}{yields}0{sup +} transition. The reliability of the intrinsic wave functions required to study these decay modes has been established in our earlier works by obtaining an overall agreement between the theoretically calculated spectroscopic properties, namely yrast spectra, reduced B(E2:0{sup +}{yields}2{sup +}) transition probabilities, quadrupole moments Q(2{sup +}) and gyromagnetic factors g(2{sup +}), and the available experimental data in the parent and daughter even-even nuclei. In the present work, the required nuclear transition matrix elements are calculated in the Majorana neutrino mass mechanism using the same set of intrinsic wave functions as used to study the two neutrino positron double-{beta} decay modes. Limits on effective light neutrino mass and effective heavy neutrino mass are extracted from the observed limits on half-lives T{sub 1/2}{sup 0{nu}}(0{sup +}{yields}0{sup +}) of ({beta}{sup +}{beta}{sup +}){sub 0{nu}} and ({epsilon}{beta}{sup +}){sub 0{nu}} modes. We also investigate the effect of quadrupolar correlations vis-a-vis deformation on nuclear transition matrix elements (NTMEs) required to study the ({beta}{sup +}{beta}{sup +}){sub 0{nu}} and ({epsilon}{beta}{sup +}){sub 0{nu}} modes.

  7. Double Beta Decays and Neutrinos - Experiments and MOON

    SciTech Connect

    Ejiri, H. [Research Center for Nuclear Physics, Osaka University, Osaka 567-0047, Japan, Nuclear Science, Czech Technical University, Brehova, Prague (Czech Republic); National Institute of Radiological Sciences, Chiba, 263-8555 (Japan)

    2008-01-24

    This is a brief review of the present and future experiments of neutrino-less double beta decays (0{nu}{beta}{beta}) and the MOON (Mo Observatory Of Neutrinos) project. High sensitivity 0{nu}{beta}{beta} experiments are unique and realistic probes for studying the Majorana nature of neutrinos and the absolute mass scale as suggested by neutrino oscillation experiments. MOON aims at spectroscopic 0{nu}{beta}{beta} studies with the {nu}-mass sensitivity of 100-30 meV by means of a super ensemble of multilayer modules of scintillator plates and tracking detector planes.

  8. Neutrino propagation in media: Flavor, helicity, and pair correlations

    NASA Astrophysics Data System (ADS)

    Kartavtsev, A.; Raffelt, G.; Vogel, H.

    2015-06-01

    Neutrinos propagating in media (matter and electromagnetic fields) undergo flavor and helicity oscillations, where helicity transitions are instigated both by electromagnetic fields and matter currents. In addition, it has been shown that correlations between neutrinos and antineutrinos of opposite momentum can build up in anisotropic media. We rederive the neutrino equations of motion in the mean-field approximation for homogeneous yet anisotropic media, confirming previous results except for a small correction in the Majorana case. Furthermore, we derive the mean-field Hamiltonian induced by neutrino electromagnetic interactions. We also provide a phenomenological discussion of pair correlations in comparison with helicity correlations.

  9. The ANTARES Neutrino Telescope

    E-print Network

    Chiara Perrina

    2015-05-01

    At about 40 km off the coast of Toulon (France), anchored at 2475 m deep in the Mediterranean Sea, there is ANTARES: the first undersea neutrino telescope and the only one currently operating. The detector consists of 885 photomultiplier tubes arranged into 12 strings of 450-metres high, with the aim to detect the Cherenkov light induced by the charged superluminal interaction products of neutrinos. Its main scientific target is the search for high-energy (TeV and beyond) neutrinos from cosmic accelerators, as predicted by hadronic interaction models, and the measurement of the cosmic neutrino diffuse flux, focusing in particular on events coming from below the horizon (up-going events) in order to significantly reduce the atmospheric muons background. Thanks to the development of a strategy for the identification of neutrinos coming from above the horizon (down-going events) the field of view of the telescope will be extended.

  10. The ANTARES Neutrino Telescope

    E-print Network

    Perrina, Chiara

    2015-01-01

    At about 40 km off the coast of Toulon (France), anchored at 2475 m deep in the Mediterranean Sea, there is ANTARES: the first undersea neutrino telescope and the only one currently operating. The detector consists of 885 photomultiplier tubes arranged into 12 strings of 450-metres high, with the aim to detect the Cherenkov light induced by the charged superluminal interaction products of neutrinos. Its main scientific target is the search for high-energy (TeV and beyond) neutrinos from cosmic accelerators, as predicted by hadronic interaction models, and the measurement of the cosmic neutrino diffuse flux, focusing in particular on events coming from below the horizon (up-going events) in order to significantly reduce the atmospheric muons background. Thanks to the development of a strategy for the identification of neutrinos coming from above the horizon (down-going events) the field of view of the telescope will be extended.

  11. Astroparticle physics with solar neutrinos.

    PubMed

    Nakahata, Masayuki

    2011-01-01

    Solar neutrino experiments observed fluxes smaller than the expectations from the standard solar model. This discrepancy is known as the "solar neutrino problem". Flux measurements by Super-Kamiokande and SNO have demonstrated that the solar neutrino problem is due to neutrino oscillations. Combining the results of all solar neutrino experiments, parameters for solar neutrino oscillations are obtained. Correcting for the effect of neutrino oscillations, the observed neutrino fluxes are consistent with the prediction from the standard solar model. In this article, results of solar neutrino experiments are reviewed with detailed descriptions of what Kamiokande and Super-Kamiokande have contributed to the history of astroparticle physics with solar neutrino measurements. (Communicated by Toshimitsu Yamazaki, M.J.A.). PMID:21558758

  12. On the nature of the fourth generation neutrino and its implications

    E-print Network

    Aparici, Alberto; Rius, Nuria; Santamaria, Arcadi

    2012-01-01

    We consider the neutrino sector of a Standard Model with four generations. While the three light neutrinos can obtain their masses from a variety of mechanisms with or without new neutral fermions, fourth-generation neutrinos need at least one new relatively light right-handed neutrino. If lepton number is not conserved this neutrino must have a Majorana mass term whose size depends on the underlying mechanism for lepton number violation. Majorana masses for the fourth generation neutrinos induce relative large two-loop contributions to the light neutrino masses which could be even larger than the cosmological bounds. This sets strong limits on the mass parameters and mixings of the fourth generation neutrinos.

  13. Neutrino-neutrino interactions in a supernova and their effect on neutrino flavor conversions

    SciTech Connect

    Dighe, Amol [Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005 (India)

    2011-11-23

    The neutrino-neutrino interactions inside a supernova core give rise to nonlinear collective effects that significantly influence the neutrino flavor conversions inside the star. I shall describe these interactions, the new oscillation phenomena they generate, and their effect on the neutrino fluxes arriving at the earth.

  14. Tau Neutrinos Favored over Sterile Neutrinos in Atmospheric Muon Neutrino Oscillations

    Microsoft Academic Search

    S. Fukuda; Y. Fukuda; M. Ishitsuka; Y. Itow; T. Kajita; J. Kameda; K. Kaneyuki; K. Kobayashi; Y. Koshio; M. Miura; S. Moriyama; M. Nakahata; S. Nakayama; Y. Obayashi; A. Okada; K. Okumura; N. Sakurai; M. Shiozawa; Y. Suzuki; H. Takeuchi; Y. Takeuchi; T. Toshito; Y. Totsuka; S. Yamada; M. Earl; A. Habig; E. Kearns; M. D. Messier; K. Scholberg; J. L. Stone; L. R. Sulak; C. W. Walter; M. Goldhaber; T. Barszczak; D. Casper; W. Gajewski; W. R. Kropp; S. Mine; L. R. Price; M. Smy; H. W. Sobel; M. R. Vagins; K. S. Ganezer; W. E. Keig; R. W. Ellsworth; S. Tasaka; A. Kibayashi; J. G. Learned; S. Matsuno; D. Takemori; Y. Hayato; T. Ishii; T. Kobayashi; K. Nakamura; Y. Oyama; A. Sakai; M. Sakuda; O. Sasaki; M. Kohama; A. T. Suzuki; T. Inagaki; K. Nishikawa; T. J. Haines; E. Blaufuss; B. K. Kim; R. Sanford; R. Svoboda; M. L. Chen; J. A. Goodman; G. Guillian; G. W. Sullivan; J. Hill; C. K. Jung; K. Martens; M. Malek; C. Mauger; C. McGrew; E. Sharkey; B. Viren; C. Yanagisawa; M. Kirisawa; S. Inaba; C. Mitsuda; K. Miyano; H. Okazawa; C. Saji; M. Takahashi; M. Takahata; Y. Nagashima; K. Nitta; M. Takita; M. Yoshida; S. B. Kim; T. Ishizuka; M. Etoh; Y. Gando; T. Hasegawa; K. Inoue; K. Ishihara; T. Maruyama; J. Shirai; M. Koshiba; Y. Hatakeyama; Y. Ichikawa; M. Koike; K. Nishijima; H. Fujiyasu; H. Ishino; M. Morii; Y. Watanabe; U. Golebiewska; D. Kielczewska; S. C. Boyd; A. L. Stachyra; R. J. Wilkes; K. K. Young

    2000-01-01

    The previously published atmospheric neutrino data did not distinguish whether muon neutrinos were oscillating into tau neutrinos or sterile neutrinos, as both hypotheses fit the data. Using data recorded in 1100 live days of the Super-Kamiokande detector, we use three complementary data samples to study the difference in zenith angle distribution due to neutral currents and matter effects. We find

  15. Schemes and Mechanisms of Neutrino Mixings (Oscillations) and a Solution of the Sun Neutrinos Deficit Problem

    E-print Network

    Kh. M. Beshtoev

    2004-06-07

    Three schemes of neutrino mixings (oscillations) are proposed. The problems of origin of angle mixings, with the law of energy-momentum conservation and disintegration of neutrino as wave pocket are solved. These two schemes belong to mass mixings schemes, where mixing angles and oscillation lengths are expressed via elements of mass matrix. The third scheme belongs to the charge mixings scheme, where mixing parameters are expressed via neutrino weak charges, as it takes place in the vector dominance model. Using experiments we must decide which of these schemes is realized indeed. Analysis of the resonance enhancement mechanism of neutrino oscillations in matter is performed. It is shown that there are no indications on existence of this effect. It is shown that the supposition that the neutrinos are Majorana particles is not confirmed by accelerator experiments. Then only mixings (oscillations) between Dirac neutrinos with different flavors without sterile neutrinos can be realized. Using all the present experimental data and the theoretical results the problem of Sun neutrinos deficit is analyzed. The conclusion is: the primary Sun $\

  16. Neutrino masses and Neutrinoless Double Beta Decay: Status and expectations

    E-print Network

    Oliviero Cremonesi

    2010-02-07

    Two most outstanding questions are puzzling the world of neutrino Physics: the possible Majorana nature of neutrinos and their absolute mass scale. Direct neutrino mass measurements and neutrinoless double beta decay (0nuDBD) are the present strategy to solve the puzzle. Neutrinoless double beta decay violates lepton number by two units and can occurr only if neutrinos are massive Majorana particles. A positive observation would therefore necessarily imply a new regime of physics beyond the standard model, providing fundamental information on the nature of the neutrinos and on their absolute mass scale. After the observation of neutrino oscillations and given the present knowledge of neutrino masses and mixing parameters, a possibility to observe 0nuDBDD at a neutrino mass scale in the range 10-50 meV could actually exist. This is a real challenge faced by a number of new proposed projects. Present status and future perpectives of neutrinoless double-beta decay experimental searches is reviewed. The most important parameters contributing to the experimental sensitivity are outlined. A short discussion on nuclear matrix element calculations is also given. Complementary measurements to assess the absolute neutrino mass scale (cosmology and single beta decays) are also discussed.

  17. Neutrinoless Double Beta Decay and Neutrino Masses

    E-print Network

    Michael Duerr

    2012-06-04

    Neutrinoless double beta decay is a promising test for lepton number violating physics beyond the standard model of particle physics. There is a deep connection between this decay and the phenomenon of neutrino masses. In particular, we will discuss the relation between neutrinoless double beta decay and Majorana neutrino masses provided by the so-called Schechter--Valle theorem in a quantitative way. Furthermore, we will present an experimental cross check to discriminate neutrinoless double beta decay from unknown nuclear background using only one isotope, i.e., within one experiment.

  18. Neutrinoless double beta decay and neutrino masses

    SciTech Connect

    Duerr, Michael [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany)

    2012-07-27

    Neutrinoless double beta decay (0{nu}{beta}{beta}) is a promising test for lepton number violating physics beyond the standard model (SM) of particle physics. There is a deep connection between this decay and the phenomenon of neutrino masses. In particular, we will discuss the relation between 0{nu}{beta}{beta} and Majorana neutrino masses provided by the so-called Schechter-Valle theorem in a quantitative way. Furthermore, we will present an experimental cross check to discriminate 0{nu}{beta}{beta} from unknown nuclear background using only one isotope, i.e., within one experiment.

  19. Zero minors of the neutrino mass matrix

    SciTech Connect

    Lashin, E. I. [Abdus Salam ICTP, P.O. Box 586, 34100 Trieste (Italy); Ain Shams University, Faculty of Science, Cairo 11566 (Egypt); Department of Physics and Astronomy, College of Science, King Saud University, Riyadh (Saudi Arabia); Chamoun, N. [Abdus Salam ICTP, P.O. Box 586, 34100 Trieste (Italy); Physics Department, HIAST, P.O. Box 31983, Damascus (Syrian Arab Republic)

    2008-10-01

    We examine the possibility that a certain class of neutrino mass matrices, namely, those with two independent vanishing minors in the flavor basis, regardless of being invertible or not, is sufficient to describe current data. We compute generic formulas for the ratios of the neutrino masses and for the Majorana phases. We find that seven textures with two vanishing minors can accommodate the experimental data. We present an estimate of the mass matrix for these patterns. All of the possible textures can be dynamically generated through the seesaw mechanism augmented with a discrete Abelian symmetry.

  20. Absolute neutrino mass measurements

    SciTech Connect

    Wolf, Joachim [Karlsruhe Institute of Technology (KIT), IEKP, Postfach 3640, 76021 Karlsruhe (Germany)

    2011-10-06

    The neutrino mass plays an important role in particle physics, astrophysics and cosmology. In recent years the detection of neutrino flavour oscillations proved that neutrinos carry mass. However, oscillation experiments are only sensitive to the mass-squared difference of the mass eigenvalues. In contrast to cosmological observations and neutrino-less double beta decay (0v2{beta}) searches, single {beta}-decay experiments provide a direct, model-independent way to determine the absolute neutrino mass by measuring the energy spectrum of decay electrons at the endpoint region with high accuracy.Currently the best kinematic upper limits on the neutrino mass of 2.2eV have been set by two experiments in Mainz and Troitsk, using tritium as beta emitter. The next generation tritium {beta}-experiment KATRIN is currently under construction in Karlsruhe/Germany by an international collaboration. KATRIN intends to improve the sensitivity by one order of magnitude to 0.2eV. The investigation of a second isotope ({sup 137}Rh) is being pursued by the international MARE collaboration using micro-calorimeters to measure the beta spectrum. The technology needed to reach 0.2eV sensitivity is still in the R and D phase. This paper reviews the present status of neutrino-mass measurements with cosmological data, 0v2{beta} decay and single {beta}-decay.

  1. Neutrino Factory Superbeam

    E-print Network

    Patrick Huber; Walter Winter

    2007-06-19

    We discuss the optimization of a neutrino factory for large \\sin^2 2 \\theta_{13}, where we assume minimum effort on the accelerator side. This implies that we use low muon energies for the price of an optimized detection system. We demonstrate that such a neutrino factory performs excellent if combined with the electron neutrino appearance channel. Instead of the platinum channel operated with the muon neutrinos from the muon decays, we propose to use the initial superbeam from the decaying pions and kaons, which might be utilized at little extra effort. Since we assume out-of-phase bunches arriving at the same detector, we do not require electron charge identification. In addition, we can choose the proton energy such that we obtain a synergistic spectrum peaking at lower energies. We find that both the superbeam and the neutrino factory beam should used at the identical baseline to reduce matter density uncertainties, possibly with the same detector. This effectively makes the configuration a single experiment, which we call ``neutrino factory superbeam''. We demonstrate that this experiment outperforms a low-energy neutrino factory or a wide band beam alone beyond a simple addition of statistics.

  2. The search for neutrino-less double-beta decay

    NASA Astrophysics Data System (ADS)

    Tosi, D.

    2014-06-01

    The search for neutrino-less double-beta decay has been a very active field of research in the last decade. Neutrino-less double-beta decay may answer essential open questions in neutrino physics. While double-beta decay accompanied by the emission of two neutrinos is allowed by the Standard Model, the neutrino-less process requires neutrinos to be Majorana particles. Detecting this decay could determine the nature of neutrinos, the neutrino effective mass, and the mass hierarchy. Xenon-136 and germanium-76 experiments currently have the best sensitivities. For both isotopes the lifetime of neutrino-less double-beta decay has been determined to be longer than 1025 years, several orders of magnitude slower than the slowest process that has been detected. In this paper the basic theory of neutrino-less double-beta decay and its relationship to the neutrino mass are discussed. A review of the experimental efforts underway to measure this decay is presented, along with the status and sensitivity of current and near future searches.

  3. Nuclear Double-Beta Decay and Derivation of Neutrino Masses

    SciTech Connect

    Stoica, S. [Horia Hulubei National Institute for Physics and Nuclear Engineering, 407, Atomistilor Street, P.O. Box MG-6, 077125 Magurele-Bucharest (Romania)

    2008-01-24

    The standard model (SM) of weak interactions incorporates neutrinos as massless particles which are left-handed partners of the charged bosons. However, in the recent past, convincing evidence of massive neutrinos has been obtained in experiments that observe neutrino oscillations. The observation of the neutrino oscillations determines only mass square differences of the neutrino types and thereby sets a lower bound on the largest of the neutrino masses. So, the absolute scale of the neutrino masses remains still unknown. Neutrinoless double beta decay experiments are at present the most sensitive ones for measuring the absolute mass of the electron neutrino. Moreover, these are the only experiments that could answer the fundamental question of whether neutrinos are their own anti-particles, that is whether they are Majorana or Dirac particles. That is why the double-beta decay nuclear process is studied intensively both theoretically and experimentally. In this lecture I give an up-to-date review on this process. After a general introduction in which I stress the importance of the {beta}{beta} decay study for searching beyond SM physics, I refer to the calculation of nuclear matrix elements involved in {beta}{beta} decay half-lives and to the to derivation of neutrino mass in connection to other constraints coming from neutrino oscillation experiments and cosmological data.

  4. Seesaw mechanism and structure of neutrino mass matrix

    E-print Network

    E. Kh. Akhmedov; G. C. Branco; M. N. Rebelo

    1999-11-15

    We consider the seesaw mechanism of neutrino mass generation in the light of our present knowledge of the neutrino masses and mixing. We analyse the seesaw mechanism constrained by the following assumptions: (1) minimal seesaw with no Higgs triplets, (2) hierarchical Dirac masses of neutrinos, (3) large lepton mixing primarily or solely due to the mixing in the right-handed neutrino sector, and (4) unrelated Dirac and Majorana sectors of neutrino masses. We show that large mixing governing the dominant channel of the atmospheric neutrino oscillations can be naturally obtained and point out that this constrained seesaw mechanism favours the normal mass hierarchy for the light neutrinos leading to a small $V_{e3}$ entry of the lepton mixing matrix and a mass scale of the lightest right handed neutrino $M\\simeq 10^{10} - 10^{11}$ GeV. Any of the three main neutrino oscillation solutions to the solar neutrino problem can be accommodated. The inverted mass hierarchy and quasi-degeneracy of neutrinos are disfavoured in our scheme.

  5. Neutrino mass spectrum with ?? -->?s oscillations of atmospheric neutrinos

    NASA Astrophysics Data System (ADS)

    Liu, Q. Y.; Smirnov, A. Yu.

    1998-08-01

    We consider the ``standard'' spectrum of the active neutrinos (characterized by strong mass hierarchy and small mixing) with additional sterile neutrino, ?s. The sterile neutrino mixes strongly with the muon neutrino, so that ?? <-->?s oscillations solve the atmospheric neutrino problem. We show that the parametric enhancement of the ?? <-->?s oscillations occurs for the high energy atmospheric neutrinos which cross the core of the Earth. This can be relevant for the anomaly observed by the MACRO experiment. Solar neutrinos are converted both to ?? and ?s. The heaviest neutrino (~??) may compose the hot dark matter of the Universe. The phenomenology of this scenario is elaborated and crucial experimental signatures are identified. We also discuss properties of the underlying neutrino mass matrix.

  6. Nonzero ?13 and Neutrino Masses from Modified Neutrino Mixing Matrix

    NASA Astrophysics Data System (ADS)

    Damanik, Asan

    2012-06-01

    The nonzero and relatively large ?13 have been reported by Daya Bay, T2K, MINOS and Double Chooz Collaborations. In order to accommodate the nonzero ?13, we modified the tribimaximal (TB), bimaxima (BM) and democratic (DC) neutrino mixing matrices. From three modified neutrino mixing matrices, two of them (the modified BM and DC mixing matrices) can give nonzero ?13 which is compatible with the result of the Daya Bay and T2K experiments. The modified TB neutrino mixing matrix predicts the value of ?13 which is greater than the upper bound value of the latest experimental results. By using the modified neutrino mixing matrices and imposing an additional assumption that neutrino mass matrices have two zeros texture, we then obtain the neutrino mass in normal hierarchy when (M?)22 = (M?)33 = 0 for the neutrino mass matrix from the modified TB neutrino mixing matrix and (M?)11 = (M?)13 = 0 for the neutrino mass matrix from the modified DC neutrino mixing matrix. For these two patterns of neutrino mass matrices, either the atmospheric mass squared difference or the solar mass squared difference can be obtained, but not both of them simultaneously. From four patterns of two zeros texture to be considered on the obtained neutrino mass matrix from the modified BM neutrino mixing matrix, none of them can correctly predict the neutrino mass spectrum (normal or inverted hierarchy).

  7. Submarine neutrino communication

    E-print Network

    Huber, Patrick

    2009-01-01

    We discuss the possibility to use a high energy neutrino beam from a muon storage ring to provide one way communication with a submerged submarine. Neutrino interactions produce muons which can be detected either, directly when they pass through the submarine or by their emission of Cerenkov light in sea water, which, in turn, can be exploited with sensitive photo detectors. Due to the very high neutrino flux from a muon storage ring, it is sufficient to mount either detection system directly onto the hull of the submersible. The achievable data transfer rates compare favorable with existing technologies and do allow for a communication at the usual speed and depth of submarines.

  8. Submarine neutrino communication

    E-print Network

    Patrick Huber

    2010-08-20

    We discuss the possibility to use a high energy neutrino beam from a muon storage ring to provide one way communication with a submerged submarine. Neutrino interactions produce muons which can be detected either, directly when they pass through the submarine or by their emission of Cerenkov light in sea water, which, in turn, can be exploited with sensitive photo detectors. Due to the very high neutrino flux from a muon storage ring, it is sufficient to mount either detection system directly onto the hull of the submersible. The achievable data transfer rates compare favorable with existing technologies and do allow for a communication at the usual speed and depth of submarines.

  9. Neutrino time travel

    E-print Network

    James Dent; Heinrich Päs; Sandip Pakvasa; Thomas J. Weiler

    2007-12-09

    We discuss causality properties of extra-dimensional theories allowing for effectively superluminal bulk shortcuts. Such shortcuts for sterile neutrinos have been discussed as a solution to the puzzling LSND and MiniBooNE neutrino oscillation results. We focus here on the sub-category of asymmetrically warped brane spacetimes and argue that scenarios with two extra dimensions may allow for timelike curves which can be closed via paths in the extra-dimensional bulk. In principle sterile neutrinos propagating in the extra dimension may be manipulated in a way to test the chronology protection conjecture experimentally.

  10. Diffractive Interaction of Neutrinos

    NASA Astrophysics Data System (ADS)

    Kopeliovich, B. Z.; Potashnikova, I. K.; Schmidt, Iván; Siddikov, M.

    2013-06-01

    Interactions of high-energy neutrinos expose hadronic properties, in particular, contain a strong diffractive channel. The Adler relation (AR) between soft interactions of neutrinos and pions, might look as a manifestation of pion dominance. However, neutrinos cannot fluctuate to pions because of conservation of the lepton current, and interact via much heavier hadronic components. This fact leads to nontrivial relations between interactions of different hadronic species, in particular, it links diagonal and off-diagonal diffractive interactions of pions. Absorptive corrections break these relations making the AR impossible to hold universally, for any target and at any energy.

  11. Solar neutrinos: Theoretical status

    SciTech Connect

    Haxton, W.C.

    1991-12-31

    I review the standard solar model, the disparities between its predictions an the solar neutrino flux measurements of the Homestake and Kamioka 2 collaborations, and possible particle physics resolutions of this puzzle. The effects of matter, including density fluctuations and turbulence, on solar neutrino oscillations are explained by building analogies with more familiar atomic physics phenomena. These and other mechanisms are considered as possible explanations for time variations in the solar neutrino flux. Finally, I consider possible outcomes and implications of the SAGE/GALLEX gallium experiments.

  12. Solar neutrinos: Theoretical status

    SciTech Connect

    Haxton, W.C.

    1991-01-01

    I review the standard solar model, the disparities between its predictions an the solar neutrino flux measurements of the Homestake and Kamioka 2 collaborations, and possible particle physics resolutions of this puzzle. The effects of matter, including density fluctuations and turbulence, on solar neutrino oscillations are explained by building analogies with more familiar atomic physics phenomena. These and other mechanisms are considered as possible explanations for time variations in the solar neutrino flux. Finally, I consider possible outcomes and implications of the SAGE/GALLEX gallium experiments.

  13. Boxing with Neutrino Oscillations

    E-print Network

    DJ Wagner; Thomas J. Weiler

    1998-01-16

    We develop a model-independent "box" parameterization of neutrino oscillations. Oscillation probabilities are linear in these new parameters, so measurements can straightforwardly determine the box parameters which can then be manipulated to yield magnitudes of mixing matrix elements. We examine the effects of unitarity On the box parameters and reduce the number of parameters to the minimum set. Using the box algebra, we show that CP-violation may be inferred from measurements of neutrino flavor mixing even when the oscillatory factor has averaged. The framework presented here will facilitate general analyses of neutrino oscillations among $n\\ge 3$ flavors.

  14. Reactor Neutrino Experiments

    E-print Network

    Jun Cao

    2007-12-06

    Precisely measuring $\\theta_{13}$ is one of the highest priority in neutrino oscillation study. Reactor experiments can cleanly determine $\\theta_{13}$. Past reactor neutrino experiments are reviewed and status of next precision $\\theta_{13}$ experiments are presented. Daya Bay is designed to measure $\\sin^22\\theta_{13}$ to better than 0.01 and Double Chooz and RENO are designed to measure it to 0.02-0.03. All are heading to full operation in 2010. Recent improvements in neutrino moment measurement are also briefed.

  15. Atmospheric neutrino oscillations and tau neutrinos in ice

    SciTech Connect

    Giordano, Gerardo; Mocioiu, Irina [Department of Physics, Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Mena, Olga [Instituto de Fisica Corpuscular, IFIC, CSIC and Universidad de Valencia (Spain)

    2010-06-01

    The main goal of the IceCube Deep Core Array is to search for neutrinos of astrophysical origins. Atmospheric neutrinos are commonly considered as a background for these searches. We show here that cascade measurements in the Ice Cube Deep Core Array can provide strong evidence for tau neutrino appearance in atmospheric neutrino oscillations. Controlling systematic uncertainties will be the limiting factor in the analysis. A careful study of these tau neutrinos is crucial, since they constitute an irreducible background for astrophysical neutrino detection.

  16. Leptoquarks: Neutrino masses and accelerator phenomenology

    E-print Network

    D. Aristizabal Sierra; M. Hirsch; S. G. Kovalenko

    2007-10-30

    Leptoquark-Higgs interactions induce mixing between leptoquark states with different chiralities once the electro-weak symmetry is broken. In such LQ models Majorana neutrino masses are generated at 1-loop order. Here we calculate the neutrino mass matrix and explore the constraints on the parameter space enforced by the assumption that LQ-loops explain current neutrino oscillation data. LQs will be produced at the LHC, if their masses are at or below the TeV scale. Since the fermionic decays of LQs are governed by the same Yukawa couplings, which are responsible for the non-trivial neutrino mass matrix, several decay branching ratios of LQ states can be predicted from measured neutrino data. Especially interesting is that large lepton flavour violating rates in muon and tau final states are expected. In addition, the model predicts that, if kinematically possible, heavier LQs decay into lighter ones plus either a standard model Higgs boson or a $Z^0/W^{\\pm}$ gauge boson. Thus, experiments at the LHC might be able to exclude the LQ mechanism as explanation of neutrino data.

  17. High Energy Cosmic Neutrinos

    E-print Network

    Steven W. Barwick

    1999-03-31

    While the general principles of high-energy neutrino detection have been understood for many years, the deep, remote geographical locations of suitable detector sites have challenged the ingenuity of experimentalists, who have confronted unusual deployment, calibration, and robustness issues. Two high energy neutrino programs are now operating (Baikal and AMANDA), with the expectation of ushering in an era of multi-messenger astronomy, and two Mediterranean programs have made impressive progress. The detectors are optimized to detect neutrinos with energies of the order of 1-10 TeV, although they are capable of detecting neutrinos with energies of tens of MeV to greater than PeV. This paper outlines the interdisciplinary scientific agenda, which span the fields of astronomy, particle physics, and cosmic ray physics, and describes ongoing worldwide experimental programs to realize these goals.

  18. WMAPping out Neutrino Masses

    SciTech Connect

    Pierce, Aaron T

    2003-02-18

    Recent data from the Wilkinson Microwave Anisotropy Probe (WMAP) place important bounds on the neutrino sector. The precise determination of the baryon number in the universe puts a strong constraint on the number of relativistic species during Big-Bang Nucleosynthesis. WMAP data, when combined with the 2dF Galaxy Redshift Survey (2dFGRS), also directly constrain the absolute mass scale of neutrinos. These results conflict with a neutrino oscillation interpretation of the result from the Liquid Scintillator Neutrino Detector (LSND) over the entire favored mixing region. We also note that the Heidelberg--Moscow evidence for neutrinoless double beta decay is only consistent with the WMAP+2dFGRS data for the largest values of the nuclear matrix element.

  19. Neutrino properties from cosmology

    NASA Astrophysics Data System (ADS)

    Verde, Licia

    2015-04-01

    In the past few years there have been new developments in the effort of constraining neutrino properties with cosmology. The Cosmic Microwave Background has been measured with renewed and improved precision and large-scale structure surveys have mapped cosmological structures in the Universe over unprecedentedly large volumes. Future, massive large-scale structure surveys have been presented and approved. On the theory side, a significant effort has been devoted to achieve better modelling of small scale clustering and of cosmological non-linearities. As a result it has become clear that forthcoming cosmological data have, in principle, enough statistical power to detect the effect of non-zero neutrino mass (even at the lower mass scale limit imposed by oscillations) and to constrain the absolute neutrino mass scale. I will present some recent work on constraints on neutrino properties from cosmology, concentrating in particular on the work done by my group and my collaborators.

  20. The ANTARES neutrino telescope

    E-print Network

    Juan de Dios Zornoza; Juan Zúñiga

    2012-10-10

    The ANTARES collaboration completed the installation of the first neutrino detector in the sea in 2008. It consists of a three dimensional array of 885 photomultipliers to gather the Cherenkov photons induced by relativistic muons produced in charged-current interactions of high energy neutrinos close to/in the detector. The scientific scope of neutrino telescopes is very broad: the origin of cosmic rays, the origin of the TeV photons observed in many astrophysical sources or the nature of dark matter. The data collected up to now have allowed us to produce a rich output of physics results, including the map of the neutrino sky of the Southern hemisphere, search for correlations with GRBs, flaring sources, gravitational waves, limits on the flux produced by dark matter self-annihilations, etc. In this paper a review of these results is presented.

  1. Neutrino mass: Recent results

    SciTech Connect

    Robertson, R.G.H.

    1989-01-01

    Some recent developments in the experimental search for neutrino mass are discussed. Simpson and Hime report finding new evidence for a 17-keV neutrino in the {beta} decay of {sup 3}H and {sup 35}S. New data from Los Alamos on the electron neutrino mass as measured in tritium beta decay give an upper limit of 13.5 eV at the 95% confidence level. This result is not consistent with the long-standing ITEP result of 26(5) eV within a model-independent'' range of 17 to 40 eV. It now appears that the electron neutrino is not sufficiently massive to close the universe by itself. 38 refs., 1 figs., 2 tabs.

  2. Double beta decay and neutrino mass models

    NASA Astrophysics Data System (ADS)

    Helo, J. C.; Hirsch, M.; Ota, T.; dos Santos, F. A. Pereira

    2015-05-01

    Neutrinoless double beta decay allows to constrain lepton number violating extensions of the standard model. If neutrinos are Majorana particles, the mass mechanism will always contribute to the decay rate, however, it is not a priori guaranteed to be the dominant contribution in all models. Here, we discuss whether the mass mechanism dominates or not from the theory point of view. We classify all possible (scalar-mediated) short-range contributions to the decay rate according to the loop level, at which the corresponding models will generate Majorana neutrino masses, and discuss the expected relative size of the different contributions to the decay rate in each class. Our discussion is general for models based on the SM group but does not cover models with an extended gauge. We also work out the phenomenology of one concrete 2-loop model in which both, mass mechanism and short-range diagram, might lead to competitive contributions, in some detail.

  3. Atmospheric neutrino oscillations with PINGU

    NASA Astrophysics Data System (ADS)

    Odrowski, Sirin; IceCube-PINGU collaboration

    2015-04-01

    Measurements of atmospheric, solar, reactor and accelerator neutrinos (see e.g. [1, 2, 3, 4]) have shown that neutrinos undergo flavour-changing oscillations and hence have mass. The cubic-kilometre neutrino detector IceCube [5] with its more densely instrumented inner region DeepCore [6] has studied oscillations of atmospheric neutrinos at energies above ? 10 GeV [7, 8, 9]. The Precision IceCube Next Generation Upgrade (PINGU) [10] is a proposed extension of IceCube with the goal to perform precise measurements of atmospheric neutrino oscillations down to a few GeV and to determine the neutrino mass hierarchy (NMH).

  4. Experimental High Energy Neutrino Astrophysics

    SciTech Connect

    Distefano, Carla [Laboratori Nazionali del Sud, Catania (Italy)

    2005-10-12

    Neutrinos are considered promising probes for high energy astrophysics. More than four decades after deep water Cerenkov technique was proposed to detect high energy neutrinos. Two detectors of this type are successfully taking data: BAIKAL and AMANDA. They have demonstrated the feasibility of the high energy neutrino detection and have set first constraints on TeV neutrino production astrophysical models. The quest for the construction of km3 size detectors have already started: in the South Pole, the IceCube neutrino telescope is under construction; the ANTARES, NEMO and NESTOR Collaborations are working towards the installation of a neutrino telescope in the Mediterranean Sea.

  5. Electromagnetic properties of massive neutrinos

    SciTech Connect

    Dobrynina, A. A., E-mail: aleksandradobrynina@rambler.ru; Mikheev, N. V.; Narynskaya, E. N. [Demidov Yaroslavl State University (Russian Federation)] [Demidov Yaroslavl State University (Russian Federation)

    2013-10-15

    The vertex function for a virtual massive neutrino is calculated in the limit of soft real photons. A method based on employing the neutrino self-energy operator in a weak external electromagnetic field in the approximation linear in the field is developed in order to render this calculation of the vertex function convenient. It is shown that the electric charge and the electric dipole moment of the real neutrino are zero; only the magnetic moment is nonzero for massive neutrinos. A fourth-generation heavy neutrino of mass not less than half of the Z-boson mass is considered as a massive neutrino.

  6. Neutrino Detectors: Challenges and Opportunities

    SciTech Connect

    Soler, F. J. P. [School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ (United Kingdom)

    2011-10-06

    This paper covers possible detector options suitable at future neutrino facilities, such as Neutrino Factories, Super Beams and Beta Beams. The Magnetised Iron Neutrino Detector (MIND), which is the baseline detector at a Neutrino Factory, will be described and a new analysis which improves the efficiency of this detector at low energies will be shown. Other detectors covered include the Totally Active Scintillating Detectors (TASD), particularly relevant for a low energy Neutrino Factory, emulsion detectors for tau detection, liquid argon detectors and megaton scale water Cherenkov detectors. Finally the requirements of near detectors for long-baseline neutrino experiments will be demonstrated.

  7. Recent advances in neutrino astrophysics

    E-print Network

    Cristina Volpe

    2014-11-24

    Neutrinos are produced by a variety of sources that comprise our Sun, explosive environments such as core-collapse supernovae, the Earth and the Early Universe. The precise origin of the recently discovered ultra-high energy neutrinos is to be determined yet. These weakly interacting particles give us information on their sources, although the neutrino fluxes can be modified when neutrinos traverse an astrophysical environment. Here we highlight recent advances in neutrino astrophysics and emphasise the important progress in our understanding of neutrino flavour conversion in media.

  8. Cosmological and supernova neutrinos

    NASA Astrophysics Data System (ADS)

    Kajino, T.; Aoki, W.; Balantekin, A. B.; Cheoun, M.-K.; Hayakawa, T.; Hidaka, J.; Hirai, Y.; Kusakabe, M.; Mathews, G. J.; Nakamura, K.; Pehlivan, Y.; Shibagaki, S.; Suzuki, T.

    2014-06-01

    The Big Bang nucleosynthesis (BBN) and the cosmic microwave background (CMB) anisotropies are the pillars of modern cosmology. It has recently been suggested that axion which is a dark matter candidate in the framework of the standard model could condensate in the early universe and induce photon cooling before the epoch of the photon last scattering. Although this may render a solution to the overproduction problem of primordial 7Li abundance, there arises another serious difficulty of overproducing D abundance. We propose a hybrid dark matter model with both axions and relic supersymmetric (SUSY) particles to solve both overproduction problems of the primordial D and 7Li abundances simultaneously. The BBN also serves to constrain the nature of neutrinos. Considering non-thermal photons produced in the decay of the heavy sterile neutrinos due to the magnetic moment, we explore the cosmological constraint on the strength of neutrino magnetic moment consistent with the observed light element abundances. Core-collapse supernovae eject huge flux of energetic neutrinos which affect explosive nucleosynthesis of rare isotopes like 7Li, 11B, 92Nb, 138La and 180Ta and r-process elements. Several isotopes depend strongly on the neutrino flavor oscillation due to the Mikheyev-Smirnov-Wolfenstein (MSW) effect. Combining the recent experimental constraints on ?13 with predicted and observed supernova-produced abundance ratio 11B/7Li encapsulated in the presolar grains from the Murchison meteorite, we show a marginal preference for an inverted neutrino mass hierarchy. We also discuss supernova relic neutrinos (SRN) that may indicate the softness of the equation of state (EoS) of nuclear matter and adiabatic conditions of the neutrino oscillation.

  9. Boxing with Neutrino Oscillations

    NASA Astrophysics Data System (ADS)

    Wagner, Dj; Weiler, Thomas J.

    1998-03-01

    We have developed a model-independent ``box'' parameterization of neutrino oscillations. Oscillation probabilities are linear in these new parameters, so measurements can straighforwardly determine the box parameters which can then be manipulated to yield magnitudes of mixing matrix elements. We will present these new parameters and examine the effects of unitarity which reduce the number of independent parameters to the minimum set. The framework presented here will facilitate general analyses of neutrino oscillations among n >= 3 flavors.

  10. Radiochemical solar neutrino experiments

    E-print Network

    V. N. Gavrin; B. T. Cleveland

    2007-03-06

    Radiochemical experiments have been crucial to solar neutrino research. Even today, they provide the only direct measurement of the rate of the proton-proton fusion reaction, p + p --> d + e^+ + nu_e, which generates most of the Sun's energy. We first give a little history of radiochemical solar neutrino experiments with emphasis on the gallium experiment SAGE -- the only currently operating detector of this type. The combined result of all data from the Ga experiments is a capture rate of 67.6 +/- 3.7 SNU. For comparison to theory, we use the calculated flux at the Sun from a standard solar model, take into account neutrino propagation from the Sun to the Earth and the results of neutrino source experiments with Ga, and obtain 67.3 ^{+3.9}_{-3.5} SNU. Using the data from all solar neutrino experiments we calculate an electron neutrino pp flux at the earth of (3.41 ^{+0.76}_{-0.77}) x 10^{10}/(cm^2-s), which agrees well with the prediction from a detailed solar model of (3.30 ^{+0.13} _{-0.14}) x 10^{10}/(cm^2-s). Four tests of the Ga experiments have been carried out with very intense reactor-produced neutrino sources and the ratio of observed to calculated rates is 0.88 +/- 0.05. One explanation for this unexpectedly low result is that the cross section for neutrino capture by the two lowest-lying excited states in 71Ge has been overestimated. We end with consideration of possible time variation in the Ga experiments and an enumeration of other possible radiochemical experiments that might have been.

  11. High energy neutrino astrophysics

    E-print Network

    R. J. Protheroe

    1998-10-22

    I give a brief discussion of possible sources of high energy neutrinos of astrophysical origin over the energy range from $\\sim 10^{12}$ eV to $\\sim 10^{25}$ eV. In particular I shall review predictions of the diffuse neutrino intensity. Neutrinos from interactions of galactic cosmic rays with interstellar matter are guaranteed, and the intensity can be reliably predicted to within a factor of 2. Somewhat less certain are intensities in the same energy range from cosmic rays escaping from normal galaxies or active galactic nuclei (AGN) and interacting with intracluster gas. At higher energies, neutrinos will definitely be produced by interactions of extragalactic cosmic rays with the microwave background. With the discovery that gamma ray bursts (GRB) are extragalactic, and therefore probably the most energetic phenomena in the Universe, it seems likely that they will be copious sources of high energy neutrinos. Other sources, such as AGN and topological defects, are more speculative. However, searches for neutrinos from all of these potential sources should be made because their detection would have important implications for high energy astrophysics and cosmology.

  12. Jiangmen Underground Neutrino Observatory

    E-print Network

    Miao He; for the JUNO collaboration

    2014-12-13

    The Jiangmen Underground Neutrino Observatory (JUNO) is a multipurpose neutrino-oscillation experiment designed to determine the neutrino mass hierarchy and to precisely measure oscillation parameters by detecting reactor antineutrinos, observe supernova neutrinos, study the atmospheric, solar neutrinos and geo-neutrinos, and perform exotic searches, with a 20 kiloton liquid scintillator detector of unprecedented $3\\%$ energy resolution (at 1 MeV) at 700-meter deep underground and to have other rich scientific possibilities. Currently MC study shows a sensitivity of the mass hierarchy to be $\\overline{\\Delta\\chi^2}\\sim 11$ and $\\overline{\\Delta\\chi^2}\\sim 16$ in a relative and an absolute measurement, respectively. JUNO has been approved by Chinese Academy of Sciences in 2013, and an international collaboration was established in 2014. The civil construction is in preparation and the R$\\&$D of the detectors are ongoing. A new offline software framework was developed for the detector simulation, the event reconstruction and the physics analysis. JUNO is planning to start taking data around 2020.

  13. Neutrino electromagnetic properties and new bounds on neutrino magnetic moments

    E-print Network

    Konstantin A. Kouzakov; Alexander I. Studenikin; Mikhail B. Voloshin

    2011-12-17

    We give a brief outline of possible neutrino electromagnetic characteristics, which can indicate new physics beyond the Standard Model. Special emphasis is put on recent theoretical development in searches for neutrino magnetic moments.

  14. Measurement of Atmospheric Neutrinos at the Sudbury Neutrino Observatory

    E-print Network

    Formaggio, Joseph A.

    The Sudbury Neutrino Observatory consists of a 1 kiloton heavy water Cherenkov detector able to detect and reconstruct high-energy muons created from cosmic ray showers and atmospheric neutrino interactions. By measuring ...

  15. Introduction to direct neutrino mass measurements and KATRIN

    NASA Astrophysics Data System (ADS)

    Thümmler, T.; Katrin Collaboration

    2012-08-01

    The properties of neutrinos and especially their rest mass play an important role at the intersections of cosmology, particle physics and astroparticle physics. At present there are two complementary approaches to address this topic in laboratory experiments. The search for neutrinoless double beta decay probes whether neutrinos are Majorana particles and determines an effective neutrino mass value. On the other hand experiments such as MARE, KATRIN and the recently proposed Project 8 will investigate the spectral shape of ?-decay electrons close to their kinematic endpoint in order to determine the neutrino rest mass with a model-independent method. Here, because of neutrino flavour mixing, the neutrino mass appears as an average of all neutrino mass eigenstates contributing to the electron neutrino. The KArlsruhe TRItium Neutrino experiment (KATRIN) is currently the experiment in the most advanced status of commissioning. It combines an ultra-luminous molecular windowless gaseous tritium source with an integrating high-resolution spectrometer of MAC-E filter type. It will investigate the neutrino rest mass with 0.2 eV/c (90% C.L.) sensitivity and allow ? spectroscopy close to the T endpoint at 18.6 keV with unprecedented precision.

  16. Minimal seesaw textures with two heavy neutrinos

    SciTech Connect

    Goswami, Srubabati [Harish-Chandra Research Institute, Chhatnag Road, Jhunsi, Allahabad 211 019 (India); Physical Research Laboratory, Navrangpura, Ahmedabad -380009 (India); Watanabe, Atsushi [Harish-Chandra Research Institute, Chhatnag Road, Jhunsi, Allahabad 211 019 (India)

    2009-02-01

    We systematically analyze the Dirac and the Majorana mass matrices in seesaw models with two heavy right-handed neutrinos. We perform thorough classification of the vanishing matrix elements which are compatible with the results from the current neutrino oscillation experiments. We include the possibility of a nondiagonal Majorana mass matrix which leads to new solutions viable with data. In a basis where the Majorana mass matrix is diagonal, these solutions imply a Dirac matrix with specific relationships amongst its elements. We find that at the level of total four zeros together in m{sub D} and M{sub R} the mass matrices are almost consistent with the data but one mixing angle is predicted to be unsuitable. At the next level, i.e. with total three zeros, only seven patterns of mass matrices describe the experimental data well. The seven solutions have testable predictions for the future neutrino experiments. In particular, each solution has definite predictions about the observation of the 1-3 leptonic mixing angle and the effective mass measured in neutrinoless double beta decay. The solutions of the mass matrices contain novel texture forms and provide new insights into the lepton-generation structure. We also discuss possible connections between these textures and the tri-bimaximal mixing to search for symmetry principles behind the mass matrix structure.

  17. First neutrino observations from the Sudbury Neutrino Observatory

    Microsoft Academic Search

    R. G. Allen; G. Buhler; H. H. Chen; J. D. Anglin; J. C. Barton; E. W. Beier; M. Bercovitch; J. Bigu; S. D. Biller; R. A. Black; I. Blevis; R. J. Boardman; J. Boger; E. Bonvin; M. G. Boulay; M. G. Bowler; T. J. Bowles; S. J. Brice; M. C. Browne; T. V. Bullard; J. Cameron; Y. D. Chan; M. Chen; X. Chen; B. T. Cleveland; E. T. H. Clifford; J. H. M. Cowan; D. F. Cowen; G. A. Cox; X. Dai; F. Dalnoki-Veress; W. F. Davidson; P. J. Doe; G. Doucas; M. R. Dragowsky; C. A. Duba; F. A. Duncan; M. Dunford; J. A. Dunmore; E. D. Earle; S. R. Elliott; H. C. Evans; G. T. Ewan; J. Farine; H. Fergani; A. P. Ferraris; R. J. Ford; J. A. Formaggio; M. M. Fowler; K. Frame; E. D. Frank; W. Frati; N. Gagnon; J. V. Germani; S. Gil; K. Graham; D. R. Grant; R. L. Hahn; A. L. Hallin; E. D. Hallman; A. S. Hamer; A. A. Hamian; W. B. Handler; R. U. Haq; C. K. Hargrove; P. J. Harvey; R. Hazama; K. M. Heeger; W. J. Heintzelman; J. Heise; R. L. Helmer; J. D. Hepburn; H. Heron; J. Hewett; A. Hime; J. G. Hykawy; M. C. P. Isaac; P. Jagam; N. A. Jelley; C. Jillings; G. Jonkmans; K. Kazkaz; P. T. Keener; J. R. Klein; A. B. Knox; R. J. Komar; R. Kouzes; T. Kutter; C. C. M. Kyba; J. Law; I. T. Lawson; M. Lay; H. W. Lee; K. T. Lesko; J. R. Leslie; I. Levine; W. Locke; S. Luoma; J. Lyon; S. Majerus; H. B. Mak; J. Maneira; J. Manor; A. D. Marino; N. McCauley; D. S. McDonald; A. B. McDonald; K. McFarlane; G. McGregor; R. Meijer; C. Mifflin; G. G. Miller; G. Milton; B. A. Moffat; M. Moorhead; C. W. Nally; M. S. Neubauer; F. M. Newcomer; H. S. Ng; A. J. Noble; E. B. Norman; V. M. Novikov; M. ONeill; C. E. Okada; R. W. Ollerhead; M. Omori; J. L. Orrell; S. M. Oser; A. W. P. Poon; T. J. Radcliffe; A. Roberge; B. C. Robertson; R. G. H. Robertson; S. S. E. Rosendahl; J. K. Rowley; V. L. Rusu; E. Saettler; K. K. Schaffer; M. H. Schwendener; A. Schulke; H. Seifert; M. Shatkay; J. J. Simpson; C. J. Sims

    2001-01-01

    The first neutrino observations from the Sudbury Neutrino Observatory are presented from preliminary analyses. Based on energy, direction and location, the data in the region of interest appear to be dominated by 8B solar neutrinos, detected by the charged current reaction on deuterium and elastic scattering from electrons, with very little background. Measurements of radioactive backgrounds indicate that the measurement

  18. Global three-neutrino oscillation analysis of neutrino data

    Microsoft Academic Search

    M. C. Gonzalez-Garcia; M. Maltoni; C. Peña-Garay; J. W. Valle

    2001-01-01

    A global analysis of the solar, atmospheric and reactor neutrino data is presented in terms of three-neutrino oscillations. We include the most recent solar neutrino rates of Homestake, SAGE, GALLEX and GNO, as well as the recent 1117 day Super-Kamiokande data sample, including the recoil electron energy spectrum both for day and night periods, and we treat in a unified

  19. Solid Target for a Neutrino Factory Neutrino Factory Target Concepts

    E-print Network

    McDonald, Kirk

    of the target material. These shocks can potentially exceed the mechanical strength of solid materialsSolid Target for a Neutrino Factory Neutrino Factory Target Concepts Parameters of the Neutrino Factory Target Proton Beam pulsed 50 Hz bunches 3 (2 ns rms) energy 10 GeV beam power 4 MW Target (not

  20. High Energy Neutrinos from Blazars

    E-print Network

    R. J. Protheroe

    1996-07-31

    I describe a model of energetic gamma ray and neutrino emission in blazars which is consistent with most of the gamma-ray observations, and use this model to estimate the diffuse intensity of high energy neutrinos from blazars.

  1. Sterile neutrinos at a Neutrino Factory

    SciTech Connect

    Lopez-Pavon, Jacobo [Instituto Fisica Teorica UAM/CSIC, Cantoblanco, E-28049 Madrid (Spain)

    2010-03-30

    We study the potential of a Neutrino Factory (NF) to constrain the parameters of the (3+1)-scheme with a O(1)eV{sup 2} largest mass square difference, considering two set-ups: a NF with 50 GeV (20 GeV) stored muons, with two detectors of the Hybrid-MIND type located at L = 3000(4000), 7500 km. We show that the best sensitivity to sterile neutrinos can be achieved through the nu{sub m}u->nu{sub m}u and the nu{sub m}u->nu{sub t}au channels which can constrain theta{sub 34}<=12 deg. (14 deg.) and theta{sub 24}<=7.5 deg. (8 deg.) with the 50 GeV (20 GeV) NF. We also study the CP-violation in this new context showing that the CP-asymmetries in the nu{sub m}u->nu{sub t}au channel can give us the chance to see a clear new CP-violation signal associated with the sterile neutrinos.

  2. Neutrino oscillations beyond two flavours

    E-print Network

    E. Kh. Akhmedov

    2002-07-29

    I review some theoretical aspects of neutrino oscillations in the case when more than two neutrino flavours are involved. These include: approximate analytic solutions for 3-flavour (3f) oscillations in matter; matter effects in nu_mu - nu_tau oscillations; 3f effects in oscillations of solar, atmospheric, reactor and supernova neutrinos and in accelerator long-baseline experiments; CP and T violation in neutrino oscillations in vacuum and in matter; the problem of U_{e3}; 4f oscillations.

  3. Neutrinos: Windows to New Physics

    E-print Network

    R. D. Peccei

    2006-09-20

    After briefly reviewing how the symmetries of the Standard Model (SM) are affected by neutrino masses and mixings, I discuss how these parameters may arise from GUTs and how patterns in the neutrino sector may reflect some underlying family symmetry. Leptogenesis provides a nice example of how different physical phenomena may be connected to the same neutrino window of physics beyond the SM. I end with some comments on the LSND signal and briefly discuss the idea that neutrinos have environment dependent masses.

  4. Neutrino dispersion in magnetized plasma

    E-print Network

    N. V. Mikheev; E. N. Narynskaya

    2008-12-02

    The neutrino dispersion in the charge symmetric magnetized plasma is investigated. We have studied the plasma contribution into the additional energy of neutrino and obtained the simple expression for it. We consider in detail the neutrino self-energy under physical conditions of weak field, moderate field and strong field limits. It is shown that our result for neutrino dispersion in moderate magnetic field differ substantially from the previous one in the literature.

  5. A Further Study of the Frampton-Glashow-Yanagida Model for Neutrino Masses, Flavor Mixing and Baryon Number Asymmetry

    E-print Network

    Zhang, Jue

    2015-01-01

    In light of the latest neutrino oscillation data, we revisit the minimal scenario of type-I seesaw model, in which only two heavy right-handed Majorana neutrinos are introduced to account for both tiny neutrino masses and the baryon number asymmetry in our Universe. In this framework, we carry out a systematic study of the Frampton-Glashow-Yanagida ansatz by taking into account the renormalization-group running of neutrino mixing parameters and the flavor effects in leptogenesis. We demonstrate that the normal neutrino mass ordering is disfavored even in the minimal supersymmetric standard model with a large value of $\\tan \\beta$, for which the running effects could be significant. Furthermore, it is pointed out that the original scenario with a hierarchical mass spectrum of heavy Majorana neutrinos contradicts with the upper bound derived from a naturalness criterion, and the resonant mechanism with nearly-degenerate heavy Majorana neutrinos can be a possible way out.

  6. A Xenon Solar Neutrino Detector

    E-print Network

    A. Sh. Georgadze; H. V. Klapdor-Kleingrothaus; H. Päs; Yu. G. Zdesenko

    1997-07-25

    The neutrino capture by $^{131}$Xe with a threshold at 352 keV as reaction to detect solar neutrinos is examined. The most important feature of this process is its high sensitivity to beryllium neutrinos, which contribute approximately 40% to the total capture rate (45 SNU) assuming the fluxes predicted by the Standard Solar Model.

  7. Solar Neutrino Matter Effects Redux

    E-print Network

    A. B. Balantekin; A. Malkus

    2011-12-19

    Following recent low-threshold analysis of the Sudbury Neutrino Observatory and asymmetry measurements of the BOREXINO Collaboration of the solar neutrino flux, we revisit the analysis of the matter effects in the Sun. We show that solar neutrino data constrains the mixing angle $\\theta_{13}$ poorly and that subdominant Standard Model effects can mimic the effects of the physics beyond the Standard Model.

  8. Supernova Neutrinos Detection On Earth

    E-print Network

    Xin-Heng Guo; Ming-Yang Huang; Bing-Lin Young

    2009-05-12

    In this paper, we first discuss the detection of supernova neutrino on Earth. Then we propose a possible method to acquire information about $\\theta_{13}$ smaller than $1.5^\\circ$ by detecting the ratio of the event numbers of different flavor supernova neutrinos. Such an sensitivity cannot yet be achieved by the Daya Bay reactor neutrino experiment.

  9. Electromagnetic neutrino: a short review

    E-print Network

    Alexander I. Studenikin

    2014-11-09

    A short review on selected issues related to the problem of neutrino electromagnetic properties is given. After a flash look at the theoretical basis of neutrino electromagnetic form factors, constraints on neutrino magnetic moments and electric millicharge from terrestrial experiments and astrophysical observations are discussed. We also focus on some recent studies of the problem and on perspectives.

  10. Neutrino oscillations: theory and phenomenology

    E-print Network

    E. Kh. Akhmedov

    2006-10-05

    A brief overview of selected topics in the theory and phenomenology of neutrino oscillations is given. These include: oscillations in vacuum and in matter; phenomenology of 3-flavour neutrino oscillations and effective 2-flavour approximations; CP and T violation in neutrino oscillations in vacuum and in matter; matter effects on \

  11. The ^8B Neutrino Spectrum

    Microsoft Academic Search

    W. T. Winter; S. J. Freedman; J. P. Schiffer; K. E. Rehm

    2004-01-01

    Knowledge of the energy spectrum of ^8B neutrinos is an important ingredient for interpreting experiments that detect energetic neutrinos from the Sun. The neutrino spectrum deviates from the allowed approximation because of the broad alpha-unstable ^8Be final state and recoil order corrections to the beta decay. We have measured the total energy of the alpha particles emitted following the beta

  12. Simulating nonlinear neutrino flavor evolution

    Microsoft Academic Search

    Huaiyu Duan; G. M. Fuller; J. Carlson

    2008-01-01

    We discuss a new kind of astrophysical transport problem: the coherent evolution of neutrino flavor in core collapse supernovae. Solution of this problem requires a numerical approach which can simulate accurately the quantum mechanical coupling of intersecting neutrino trajectories and the associated nonlinearity which characterizes neutrino flavor conversion. We describe here the two codes developed to attack this problem. We

  13. Gravitational Lensing of Supernova Neutrinos

    SciTech Connect

    Mena, Olga; /Fermilab /Rome U.; Mocioiu, Irina; /Penn State U.; Quigg, Chris; /Fermilab

    2006-10-01

    The black hole at the center of the galaxy is a powerful lens for supernova neutrinos. In the very special circumstance of a supernova near the extended line of sight from Earth to the galactic center, lensing could dramatically enhance the neutrino flux at Earth and stretch the neutrino pulse.

  14. Effects of Spin-Flavor Conversion in Supernova Neutrino Signal

    SciTech Connect

    Yoshida, Takashi [Division of Theoretical Astronomy, National Astronomical Observatory of Japan (Japan); Takamura, Akira [Department of Mathematics, Toyota National College of Technology (Japan); Kimura, Keiichi; Yokomakura, Hidekazu [Department of Physics, Graduate School of Science, Nagoya University (Japan); Kawagoe, Shiou [Department of Astronomy, Graduate School of Science, University of Tokyo (Japan); Kajino, Toshitaka [Division of Theoretical Astronomy, National Astronomical Observatory of Japan (Japan); Department of Astronomy, Graduate School of Science, University of Tokyo (Japan)

    2009-05-04

    Majorana neutrinos with a finite transition magnetic moment are expected to convert their flavors by spin precession in a strong magnetic field of a supernova. We investigate detailed dependence of the resonant spin-flavor conversions on electron fraction Y{sub e} in the innermost region of the supernova assuming the inverted mass hierarchy. The observed supernova v-bar{sub e} spectrum is expected to be larger in Y{sub e}>0.5 than that in Y{sub e}<0.5. Therefore, the time variation of supernova v-bar{sub e} signal would indicate Majorana neutrinos with a finite transition magnetic moment.

  15. The Solar Neutrino Problem and Bounds on Solar Neutrino Fluxes

    NASA Astrophysics Data System (ADS)

    Kwong, Waikwok; Rosen, S. P.

    We review the current status of the solar neutrino problem. A survey of the experiments and their results are given, and solar physics crucial to the understanding of these results are discussed. Semi-empirical methods are used to derive bounds on the fluxes of the three most important components (pp, 7Be and 8B) of the solar neutrino spectrum. The 8B neutrinos are directly measured to be about half of the theoretical prediction. Relative to their theoretical predictions, we find the 7Be neutrinos to be highly suppressed and the pp neutrinos not suppressed. We are also able to derive a lower bound on the pp flux.

  16. Vetoing atmospheric neutrinos in a high energy neutrino telescope

    SciTech Connect

    Schoenert, Stefan; Resconi, Elisa; Schulz, Olaf [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Gaisser, Thomas K. [Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716 (United States)

    2009-02-15

    We discuss the possibility to suppress downward atmospheric neutrinos in a high energy neutrino telescope. This can be achieved by vetoing the muon which is produced by the same parent meson decaying in the atmosphere. In principle, atmospheric neutrinos with energies E{sub {nu}}>10 TeV and a zenith angle up to 60 deg. can be vetoed with an efficiency of >99%. Practical realization will depend on the depth of the neutrino telescope, on the muon veto efficiency, and on the ability to identify downward-moving neutrinos with a good energy estimation.

  17. Supernova Neutrino-Process and Implication in Neutrino Oscillation

    NASA Astrophysics Data System (ADS)

    Kajino, T.; Aoki, W.; Fujiya, W.; Mathews, G. J.; Yoshida, T.; Shaku, K.; Nakamura, K.; Hayakawa, T.

    2012-08-01

    We studied the supernova nucleosynthesis induced by neutrino interactions and found that several isotopes of rare elements like 7Li, 11B, 138La, 180Ta and many others are predominantly produced by the neutrino-process in core-collapse supernovae. These isotopes are strongly affected by the neutrino flavor oscillation due to the MSW (Mikheyev-Smirnov-Wolfenstein) effect. We here propose a new novel method to determine the unknown neutrino oscillation parameters, ?13 and mass hierarchy simultaneously from the supernova neutrino-process, combined with the r-process for heavy-element synthsis and the Galactic chemical evolution on light nuclei.

  18. Neutrino oscillometry at the next generation neutrino observatory

    E-print Network

    Yu. N. Novikov; T. Enqvist; A. N. Erykalov; F. v. Feilitzsch; J. Hissa; K. Loo; D. A. Nesterenko; L. Oberauer; F. Thorne; W. Trzaska; J. D. Vergados; M. Wurm

    2011-10-13

    The large next generation liquid-scintillator detector LENA (Low Energy Neutrino Astronomy) offers an excellent opportunity for neutrino oscillometry. The characteristic spatial pattern of very low monoenergetic neutrino disappearance from artificial radioactive sources can be detected within the long length of detector. Sufficiently strong sources of more than 1 MCi activity can be produced at nuclear reactors. Oscillometry will provide a unique tool for precise determination of the mixing parameters for both active and sterile neutrinos within the broad mass region 0.01 - 2 (eV)^2. LENA can be considered as a versatile tool for a careful investigation of neutrino oscillations.

  19. Extraterrestrial Solar Neutrino Physics

    E-print Network

    W-Y. Pauchy Hwang; Jen-Chieh Peng

    2011-07-26

    We advocate the extraterrestrial solar neutrino physics (etSNP) as a means of investigating solar neutrino physics (SNP). As we already know, the dominant and subdominant (vacuum) oscillation lengths would be approximately one kilometer and one hundred kilometers. On the other hand, we know so far that the matter-enhanced oscillations take place only in the core of the Sun. Thus, the etSNP, i.e. solar neutrino physics that could be extracted outside the Earth, would assume a special unique role. The etSNP experiments include (1) a satellite (detector) around the Earth or around the Jupiter or others (to provide the shadow, for the matter-enhanced neutrino oscillations), (2) during the Sun-Venus-Earth eclipse or similar, and (3) the chemical compositions of the geology type (as in the Jupiter or in the Venus, to study the origins of these planets). To be specific, we note that the reactions induced by the ^8B solar neutrinos, in view of the sole high energy nature (E_\

  20. The MAJORANA DEMONSTRATOR A search for neutrinoless double-beta decay of germanium-76

    E-print Network

    MAJORANA The MAJORANA DEMONSTRATOR A search for neutrinoless double-beta decay of germanium-76 DEMONSTRATOR PANIC11 Neutrinoless double-beta decay (0) · Observation indicates: · Neutrino is a Majorana Neutrino mass and 0 4 NME: Simkovic et al, Phys Ref C 79, 055501 (2009) ouble-Beta Decay nd Neutrino Mass m

  1. Limits on neutrino-neutrino scattering in the early Universe

    NASA Astrophysics Data System (ADS)

    Cyr-Racine, Francis-Yan; Sigurdson, Kris

    2014-12-01

    In the standard model neutrinos are assumed to have streamed across the Universe since they last scattered when the standard-model plasma temperature was ˜MeV . The shear stress of free-streaming neutrinos imprints itself gravitationally on the cosmic microwave background (CMB) and makes the CMB a sensitive probe of neutrino scattering. Yet, the presence of nonstandard physics in the neutrino sector may alter this standard chronology and delay neutrino free streaming until a much later epoch. We use observations of the CMB to constrain the strength of neutrino self interactions Geff and put limits on new physics in the neutrino sector from the early Universe. Within the context of conventional ? CDM parameters cosmological data are compatible with Geff?1 /(56 MeV )2 and neutrino free streaming might be delayed until their temperature has cooled to as low as ˜25 eV . Intriguingly, we also find an alternative cosmology compatible with cosmological data in which neutrinos scatter off each other until z ˜1 04 with a preferred interaction strength in a narrow region around Geff?1 /(10 MeV )2?8.6 ×1 08GF , where GF is the Fermi constant. This distinct self-interacting neutrino cosmology is characterized by somewhat lower values of both the scalar spectral index and the amplitude of primordial fluctuations. While we phrase our discussion here in terms of a specific scenario, our constraints on the neutrino visibility function are very general.

  2. Neutrino Magnetic Moments and the Solar Neutrino Problem

    E-print Network

    E. Kh. Akhmedov

    1994-05-15

    Present status of the neutrino magnetic moment solutions of the solar neutrino problem is reviewed. In particular, we discuss a possibility of reconciling different degrees of suppression and time variation of the signal (or lack of such a variation) observed in different solar neutrino experiments. It is shown that the resonant spin--flavor precession of neutrinos due to the interaction of their transitions magnetic moments with solar magnetic field can account for all the available solar neutrino data. For not too small neutrino mixing angles ($\\sin 2\\theta_0 \\aprge 0.2$) the combined effect of the resonant spin--flavor precession and neutrino oscillations can result in an observable flux of solar $\\bar{\

  3. Neutrino magnetic moments and the solar neutrino problem

    SciTech Connect

    Akhmedov, E.Kh. [Washington Univ., Seattle, WA (United States). Inst. for Nuclear Theory]|[Valencia Univ. (Spain). Dept. de Fisica Teorica

    1994-08-01

    Present status of the neutrino magnetic moment solutions of the solar neutrino problem is reviewed. In particular, we discuss a possibility of reconciling different degrees of suppression and time variation of the signal (or lack of such a variation) observed in different solar neutrino experiments. It is shown that the resonant spin-flavor precession of neutrinos due to the interaction of their transitions magnetic moments with solar magnetic field can account for all the available solar neutrino data. For not too small neutrino mixing angles (sin 2{theta}{sub o} {approx_gt} 0.2 the combined effect of the resonant spin-flavor precession and neutrino oscillations can result in an observable flux of solar {bar {nu}}{sub e}`s.

  4. Signatures of the neutrino mass hierarchy in supernova neutrinos

    E-print Network

    S. H. Chiu; Chu-Ching Huang; Kwang-Chang Lai

    2015-06-17

    The undetermined neutrino mass hierarchy may leave an observable imprint on the neutrino fluxes from a core-collapse supernova (SN). The interpretation of the observables, however, is subject to the uncertain SN models and the flavor conversion mechanism of neutrinos in a SN. We attempt to propose a qualitative interpretation of the expected neutrino events at terrestrial detectors, focusing on the accretion phase of the neutrino burst. The flavor conversions due to neutrino self-interaction, the MSW effect, and the Earth regeneration effect are incorporated in the calculation. It leads to several distinct scenarios that are identified by the neutrino mass hierarchies and the collective flavor transitions. Consequences resulting from the variation of incident angles and SN models are also discussed.

  5. Radiative scaling neutrino mass with A4 symmetry

    NASA Astrophysics Data System (ADS)

    Bhattacharya, Subhaditya; Ma, Ernest; Natale, Alexander; Rashed, Ahmed

    2013-05-01

    A new idea for neutrino mass was proposed recently, where its smallness is not due to the seesaw mechanism, i.e., not inversely proportional to some large mass scale. It comes from a one-loop mechanism with dark matter in the loop consisting of singlet Majorana fermions Ni with masses of order 10 keV, and neutrino masses are scaled down from them by factors of about 10-5. We discuss how this model may be implemented with the non-Abelian discrete symmetry A4 for neutrino mixing and consider the phenomenology of Ni as well as the extra scalar doublet (?+,?0).

  6. The neutrino signal at HALO: learning about the primary supernova neutrino fluxes and neutrino properties

    SciTech Connect

    Väänänen, Daavid; Volpe, Cristina, E-mail: vaananen@ipno.in2p3.fr, E-mail: volpe@ipno.in2p3.fr [Institut de Physique Nucléaire, F-91406 Orsay cedex, CNRS/IN2P3 and University of Paris-XI (France)

    2011-10-01

    Core-collapse supernova neutrinos undergo a variety of phenomena when they travel from the high neutrino density region and large matter densities to the Earth. We perform analytical calculations of the supernova neutrino fluxes including collective effects due to the neutrino-neutrino interactions, the Mikheev-Smirnov-Wolfenstein (MSW) effect due to the neutrino interactions with the background matter and decoherence of the wave packets as they propagate in space. We predict the numbers of one- and two-neutron charged and neutral-current electron-neutrino scattering on lead events. We show that, due to the energy thresholds, the ratios of one- to two-neutron events are sensitive to the pinching parameters of neutrino fluxes at the neutrinosphere, almost independently of the presently unknown neutrino properties. Besides, such events have an interesting sensitivity to the spectral split features that depend upon the presence/absence of energy equipartition among neutrino flavors. Our calculations show that a lead-based observatory like the Helium And Lead Observatory (HALO) has the potential to pin down important characteristics of the neutrino fluxes at the neutrinosphere, and provide us with information on the neutrino transport in the supernova core.

  7. The neutrino signal at HALO: learning about the primary supernova neutrino fluxes and neutrino properties

    E-print Network

    Daavid Väänänen; Cristina Volpe

    2011-10-20

    Core-collapse supernova neutrinos undergo a variety of phenomena when they travel from the high neutrino density region and large matter densities to the Earth. We perform analytical calculations of the supernova neutrino fluxes including collective effects due to the neutrino-neutrino interactions, the Mikheev-Smirnov-Wolfenstein (MSW) effect due to the neutrino interactions with the background matter and decoherence of the wave packets as they propagate in space. We predict the numbers of one- and two-neutron charged and neutral-current electron-neutrino scattering on lead events. We show that, due to the energy thresholds, the ratios of one- to two-neutron events are sensitive to the pinching parameters of neutrino fluxes at the neutrinosphere, almost independently of the presently unknown neutrino properties. Besides, such events have an interesting sensitivity to the spectral split features that depend upon the presence/absence of energy equipartition among neutrino flavors. Our calculations show that a lead-based observatory like the Helium And Lead Observatory (HALO) has the potential to pin down important characteristics of the neutrino fluxes at the neutrinosphere, and provide us with information on the neutrino transport in the supernova core.

  8. Probing neutrino magnetic moments at Spallation Neutron Source facilities

    E-print Network

    Kosmas, T S; Papoulias, D K; Tortola, M; Valle, J W F

    2015-01-01

    Majorana neutrino electromagnetic properties are studied through neutral current coherent neutrino-nucleus scattering. We focus on the potential of the recently planned COHERENT experiment at the Spallation Neutron Source to probe muon-neutrino magnetic moments. The resulting sensitivities are determined on the basis of a $\\chi^2$ analysis employing realistic nuclear structure calculations in the context of the quasi-particle random phase approximation (QRPA). We find that they can improve existing limits by half an order of magnitude. In addition, we show that these facilities allow for Standard Model precision tests in the low energy regime, with a competitive determination of the weak mixing angle. Finally, they also offer the capability to probe other electromagnetic neutrino properties, such as the neutrino charge-radius. We illustrate our results for various choices of experimental setup and target material.

  9. Cosmological Constraints on Neutrinos

    NASA Astrophysics Data System (ADS)

    Millea, Marius

    2015-04-01

    The cosmic background of neutrinos (the CNB) created during the big bang has been definitively detected via its gravitational influence. Ongoing measurements are now giving increasingly precise answers to questions such as 1) what is the energy density contained in the CNB? 2) what are the masses of the particles making up the CNB? and 3) are these particles really neutrinos, e.g. do they free-stream like neutrinos? I will discuss answers to these questions from cosmological probes such as baryon acoustic oscillations or local Hubble constant measurements, and with particular focus on the Planck 2015 cosmic microwave background results. One possibility I will explore is if axions of axion-like particles can be masquerading as a component of the CNB. Recent improvements from Planck and from big bang nucleosynthesis measurements have been placing increasingly tight constraints on this scenario.

  10. Popcorn Neutrino Lab

    NSDL National Science Digital Library

    Jason Petula

    Students will participate in a modeling activity that simulates the cyclical role of experimental and theoretical science. Initially, the students will measure the mass of popcorn kernels. While the mass of the kernels are determined, students will also make predictions of the mass of the kernels after they are popped. After the popcorn is popped, the mass of the popcorn is measured. Data is shared and students articulate theories that explain why the masses do not agree. After the experiment, the topic of neutrinos is introduced. Essentially, the unpopped kernels represent neutrons and the popped kernels represent protons, electrons, and neutrinos. As students relate the experiment to the theoretical discovery of the neutrino, dialogue can follow discussing the strengths and weaknesses of the model.

  11. Entanglement in neutrino oscillations

    E-print Network

    Massimo Blasone; Fabio Dell'Anno; Silvio De Siena; Fabrizio Illuminati

    2009-04-17

    Flavor oscillations in elementary particle physics are related to multi-mode entanglement of single-particle states. We show that mode entanglement can be expressed in terms of flavor transition probabilities, and therefore that single-particle entangled states acquire a precise operational characterization in the context of particle mixing. We treat in detail the physically relevant cases of two- and three-flavor neutrino oscillations, including the effective measure of CP violation. We discuss experimental schemes for the transfer of the quantum information encoded in single-neutrino states to spatially delocalized two-flavor charged lepton states, thus showing, at least in principle, that single-particle entangled states of neutrino mixing are legitimate physical resources for quantum information tasks.

  12. Ultrahigh energy neutrino scattering

    SciTech Connect

    Berger, Edmond L. [High Energy Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Block, Martin M. [Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208 (United States); McKay, Douglas W. [Department of Physics and Astronomy, University of Kansas, Lawrence, Kansas 66045 (United States); Tan, C.-I [Physics Department, Brown University, Providence, Rhode Island 02912 (United States)

    2008-03-01

    Estimates are made of ultrahigh energy neutrino cross sections based on an extrapolation to very small Bjorken x of the logarithmic Froissart dependence in x shown previously to provide an excellent fit to the measured proton structure function F{sub 2}{sup p}(x,Q{sup 2}) over a broad range of the virtuality Q{sup 2}. Expressions are obtained for both the neutral current and the charged current cross sections. Comparison with an extrapolation based on perturbative QCD shows good agreement for energies where both fit data, but our rates are as much as a factor of 10 smaller for neutrino energies above 10{sup 9} GeV, with important implications for experiments searching for extragalactic neutrinos.

  13. High-energy Cosmogenic Neutrinos

    NASA Astrophysics Data System (ADS)

    Ahlers, Markus

    Cosmic ray (CR) interactions with the cosmic radiation background are a guaranteed source of high-energy neutrinos. The most optimistic scenario assumes the dominance of CR protons at ultra-high energies (UHE) that rapidly interact with the cosmic microwave background above the Greisen-Zatsepin-Kuzmin (GZK) cutoff. The GZK neutrino prediction of this scenario is testable with present and near-future neutrino observatories. On the other hand, if heavy nuclei dominate the UHE CR spectrum the predictions of GZK neutrinos become smaller by orders of magnitude. I will review the predictions of different UHE CR models and summarize the present status of GZK neutrino searches.

  14. Review of neutrino mass measurements

    SciTech Connect

    Robertson, R.G.H.

    1988-01-01

    The current status of the experimental search for neutrino mass is reviewed, with emphasis on direct kinematic methods. New data on the /tau/ neutrino from the Argus collaboration have reduced the upper mass limit a factor of 2. The situation concerning the electron neutrino mass as measured in tritium beta decay is essentially unchanged from a year ago. Simpson and Hime report finding evidence for a 17-keV neutrino in the ..beta.. decay of /sup 35/S. There may be evidence for neutrino mass and mixing in the SN1987a data. 62 refs., 4 figs.

  15. Supernova nucleosynthesis and neutrino oscillation

    NASA Astrophysics Data System (ADS)

    Kajino, T.; Aoki, W.; Cheoun, M.-K.; Chiba, S.; Fujiya, W.; Hayakawa, T.; Mathews, G. J.; Nakamura, K.; Shaku, K.; Yoshida, T.

    2012-04-01

    Neutrinos play the critical roles in nucleosynthesis of light-to-heavy mass nuclei like 7Li, 11B, 138La and 180Ta in core-collapse supernovae. We find average neutrino temperatures of three flavor neutrinos so that the supernova nucleosynthesis models of the neutrino-process and the r-process can explain the observed solar-system abundance and Galactic chemical evolution of these isotopes. We propose a method to determine the unknown neutrino oscillation parameters ?13 and mass hierarchy by the use of the MSW effects on the supernova nucleosynthesis.

  16. Neutrino Mass Matrix Subject to $?-?$ Symmetry and Invariant under a Cyclic Permutation

    E-print Network

    Asan Damanik

    2010-06-02

    Neutrino masses arise via a seesaw mechanism and its mass hierarchy, with assumption that heavy Majorana neutrino mass matrix subject to $\\mu-\\tau$ symmetry and invariant under a cyclic permutation, are evaluated. Within this scenario, the neutrino masses: $\\left|m_{1}\\right|=\\left|m_{2}\\right|<\\left|m_{3}\\right|$ are obtained, which are incompatible with the experimental data. By modifying neutrino mass matrix with the zero sum rule condition, the neutrino masses in inverted hierarchy: $\\left|m_{3}\\right|<\\left|m_{1}\\right|<\\left|m_{2}\\right|$ are obtained.

  17. Radiative emission of neutrino pair from nucleus and inner core electrons in heavy atoms

    E-print Network

    M. Yoshimura; N. Sasao

    2013-10-24

    Radiative emission of neutrino pair (RENP) from atomic states is a new tool to experimentally investigate undetermined neutrino parameters such as the smallest neutrino mass, the nature of neutrino masses (Majorana vs Dirac), and their CP properties. We study effects of neutrino pair emission either from nucleus or from inner core electrons in which the zero-th component of quark or electron vector current gives rise to large coupling. Both the overall rate and the spectral shape of photon energy are given for a few cases of interesting target atoms. Calculated rates exceed those of previously considered target atoms by many orders of magnitudes.

  18. Neutrino masses and mixing, quark-lepton symmetry, and strong right-handed neutrino hierarchy

    NASA Astrophysics Data System (ADS)

    Dermíšek, Radovan

    2004-10-01

    Assuming the same form of all mass matrices as motivated by quark-lepton symmetry, we discuss conditions under which bilarge mixing in the lepton sector can be obtained with a minimal amount of fine-tuning requirements for possible models. We assume hierarchical mass matrices, dominated by the 3-3 element, with off-diagonal elements much smaller than the larger neighboring diagonal element. Characteristic features of this scenario are strong hierarchy in masses of right-handed neutrinos, and comparable contributions of both lighter right-handed neutrinos to the resulting left-handed neutrino Majorana mass matrix. Because of obvious quark-lepton symmetry, this approach can be embedded into grand unified theories. The mass of the lightest neutrino does not depend on details of a model in the leading order. The right-handed neutrino scale can be identified with the GUT scale in which case the mass of the lightest neutrino is given as (m2top/MGUT)|U?1|2.

  19. Flavor oscillations of supernova neutrinos

    NASA Astrophysics Data System (ADS)

    Mirizzi, Alessandro

    2012-08-01

    Neutrinos emitted by core-collapse supernovae (SNe) represent an important laboratory for both particle physics and astrophysics. While propagating in the dense SN environment, they can feel not only the presence of background matter (via ordinary Mikheev-Smirnov-Wolfenstein effects) but also of the gas of neutrinos and antineutrinos (via neutrino-neutrino interaction effects). The MSW effect would imprint on SN neutrinos a track of the shock-wave propagation and of the matter turbulences in the stellar envelope. Moreover, the neutrino-neutrino interactions appear to modify the flavor evolution of SN neutrinos in a collective way, completely different from the ordinary matter effects. In these conditions, the flavor evolution equations become highly nonlinear, sometimes resulting in surprising phenomena when the entire neutrino system oscillates coherently as a single collective mode. In this talk, I will present the recent results on supernova neutrino flavor conversions and I will discuss about the sensitivity of these effects to the ordering of the neutrino mass spectrum.

  20. The problems with solar neutrinos

    SciTech Connect

    Beier, E.W. [Department of Physics, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6396 (United States)

    1995-05-10

    Nuclear fusion processes in the center of the sun produce neutrinos as well as photons. Detection of these neutrinos constrains both the intrinsic properties of the neutrinos, such as their mass and mixing, and the models of the sun used to calculate the solar neutrino flux. Three new experiments have reported measurements of solar neutrinos in the past five years, supplementing the pioneering experiment begun in the Homestake mine in South Dakota in the 1960`s. These experiments expose two problems which may indicate that neutrinos have non-zero mass. The next generation of experiments will determine if non-zero neutrino mass effects are the cause of the problems observed in the existing data. A brief summary of progress and the future resolution of these problems is presented. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

  1. Neutrino mass and mixing implied by underground deficit of low energy muon-neutrino events

    Microsoft Academic Search

    John G. Learned; Sandip Pakvasa; Thomas J. Weiler

    1988-01-01

    Recent observations of a deficit of cosmic ray muon-neutrino interactions in underground detectors suggest that the muon neutrinos may have oscillated to another state. We examine possible neutrino mass and mixing patterns, and their implications for vacuum and matter effects on solar neutrinos, on neutrinos passing through the earth, and on terrastrial neutrino beams. By invoking the see-saw mechanism of

  2. Nonstandard neutrino interactions and transition magnetic moments

    E-print Network

    Kristopher J. Healey; Alexey A. Petrov; Dmitry Zhuridov

    2014-03-03

    We constrain generic nonstandard neutrino interactions with existing experimental data on neutrino transition magnetic moments and derive strong bounds on tensorial couplings of neutrinos to charged fermions. We also discuss how some of these tensorial couplings can be constrained by other experiments, e.g., on neutrino-electron and neutrino-nucleus scattering.

  3. Neutrinoless double beta decay and neutrino physics

    E-print Network

    Werner Rodejohann

    2012-08-20

    The connection of neutrino physics with neutrinoless double beta decay is reviewed. After presenting the current status of the PMNS matrix and the theoretical background of neutrino mass and lepton mixing, we will summarize the various implications of neutrino physics for double beta decay. The influence of light sterile neutrinos and other exotic modifications of the three neutrino picture is also discussed.

  4. The Neutrinoless Double Beta Decay, Physics beyond the Standard Model and the Neutrino Mass

    E-print Network

    Amand Faessler

    2012-03-16

    The Neutrinoless double beta Decay allows to determine the effectice Majorana electron neutrino mass. For this the following conditions have to be satisfied: (i) The neutrino must be a Majorana particle, i. e. identical to the antiparticle. (ii) The half life has to be measured. (iii)The transition matrix element must be reliably calculated. (iv) The leading mechanism must be the light Majorana neutrino exchange. The present contribution studies the accuracy with which one can calculate by different methods: (1) Quasi-Particle Random Phase Approach (QRPA), (2) the Shell Model (SM), (3) the (before the variation) angular momentum projected Hartree-Fock-Bogoliubov method (PHFB)and the (4) Interacting Boson Approach (IBA). In the second part we investigate how to determine experimentally the leading mechanism for the Neutrinoless Double Beta Decay. Is it (a) the light Majorana neutrino exchange as one assumes to determine the effective Majorana neutrino mass, ist it the heavy left (b) or right handed (c) Majorana neutrino exchange allowed by left-right symmetric Grand Unified Theories (GUT's). Is it a mechanism due to Supersymmetry e.g. with gluino exchange and R-parity and lepton number violating terms. At the end we assume, that Klapdor et al. have indeed measured the Neutrinoless Double Beta Decay(, although contested,)and that the light Majorana neutrino exchange is the leading mechanism. With our matrix elements we obtain then an effective Majorana neutrino mass of: = 0.24 [eV], exp (pm) 0.02; theor. (pm) 0.01 [eV

  5. Experimental Neutrino Physics

    ScienceCinema

    Chris Walter

    2010-01-08

    In this talk, I will review how a set of experiments in the last decade has given us our current understanding of neutrino properties.  I will show how experiments in the last year or two have clarified this picture, and will discuss how new experiments about to start will address remaining questions.  I will particularly emphasize the relationship between various experimental techniques.

  6. Low energy neutrinos

    NASA Astrophysics Data System (ADS)

    Ranucci, G.; Bellini, G.; Benziger, J.; Bick, D.; Bonfini, G.; Bravo, D.; Buizza Avanzini, M.; Caccianiga, B.; Cadonati, L.; Calaprice, F.; Cavalcante, P.; Chavarria, A.; Chepurnov, A.; D'Angelo, D.; Davini, S.; Derbin, A.; Empl, A.; Etenko, A.; Fomenko, K.; Franco, D.; Galbiati, C.; Gazzana, S.; Ghiano, C.; Giammarchi, M.; Goeger-Neff, M.; Goretti, A.; Grandi, L.; Hagner, C.; Hungenford, E.; Ianni, Al.; Ianni, An.; Kobychev, V.; Korablev, D.; Korga, G.; Kryn, D.; Laubenstein, M.; Lewke, T.; Litvinovich, E.; Loer, B.; Lombardi, F.; Lombardi, P.; Ludhova, L.; Lukyanchenko, G.; Machulin, I.; Manecki, S.; Maneschg, W.; Manuzio, G.; Meindl, Q.; Meroni, E.; Miramonti, L.; Misiaszek, M.; Mllenberg, R.; Mosteiro, P.; Muratova, V.; Oberauer, L.; Obolensky, M.; Ortica, F.; Otis, K.; Pallavicini, M.; Papp, L.; Perasso, L.; Perasso, S.; Pocar, A.; Raghavan, R. S.; Ranucci, G.; Razeto, A.; Re, A.; Romani, A.; Rossi, N.; Saldanha, R.; Salvo, C.; Schönert, S.; Simgen, H.; Skorokhvatov, M.; Smirnov, O.; Sotnikov, A.; Sukhotin, S.; Suvorov, Y.; Tartaglia, R.; Testera, G.; Vignaud, D.; Vogelaar, R. B.; von Feilitzsch, F.; Winter, J.; Wojcik, M.; Wright, A.; Wurm, M.; Xu, J.; Zaimidoroga, O.; Zavatarelli, S.; Zuzel, G.

    2014-05-01

    Low energy neutrino investigation has been one of the most active fields of particle physics research over the past decades, accumulating important and sometimes unexpected achievements. In this work some of the most recent impressive successes will be reviewed, as well as the future perspectives of this exciting area of study.

  7. Neutrinos from Protoneutron Stars

    E-print Network

    S. Reddy; J. Pons; M. Prakash; J. M. Lattimer

    1998-02-24

    We study the diffusive transport of neutrinos in a newly born neutron star to explore its sensitivity to dense matter properties. Energy and lepton number which are trapped during the catastrophic implosion diffuse out on the time scale of a few tens of seconds. Results for different dense matter models are presented.

  8. Chlorine solar neutrino experiment

    SciTech Connect

    Rowley, J.K.; Cleveland, B.T.; Davis R. Jr.

    1985-01-25

    The chlorine solar neutrino experiment in the Homestake Gold Mine is described and the results obtained with the chlorine detector over the last fourteen years are summarized and discussed. Background processes producing /sup 37/Ar and the question of the constancy of the production rate of /sup 37/Ar are given special emphasis.

  9. Chlorine solar neutrino experiment

    SciTech Connect

    Rowley, J.K.; Cleveland, B.T.; Davis, R. Jr.

    1984-01-01

    The chlorine solar neutrino experiment in the Homestake Gold Mine is described and the results obtained with the chlorine detector over the last fourteen years are summarized and discussed. Background processes producing /sup 37/Ar and the question of the constancy of the production rate of /sup 37/Ar are given special emphasis.

  10. Neutrino factory in Japan

    NASA Astrophysics Data System (ADS)

    Mori, Yoshiharu

    2000-11-01

    A possible scheme of the neutrino factory in Japan based on the 50-GeV PS of the KEK-JAERI joint project is described. In this scheme, beam power of about 1 MW is expected from the 50-GeV PS with a repetition rate of about 0.4 Hz.

  11. Flavour-dependent radiative correction to neutrino-neutrino refraction

    NASA Astrophysics Data System (ADS)

    Mirizzi, Alessandro; Pozzorini, Stefano; Raffelt, Georg G.; Serpico, Pasquale D.

    2009-10-01

    In the framework of the Standard Model we calculate the flavour non-universal correction for neutrino refraction in a neutrino background and verify a similar previous result for the case of ordinary-matter background. The dominant term arises at loop level and involves ? leptons circulating in the loop. These Script O(GFm?2) corrections to the tree-level potential provide the dominant refractive difference between ?? and ?? unless the medium contains ? or ? leptons. Our results affect the flavour evolution of dense neutrino gases and may be of interest for collective three-flavour oscillations of supernova neutrinos. We spell out explicitly how these non-universal neutrino-neutrino interactions enter the flavour oscillation equations.

  12. Precision Solar Neutrino Measurements with the Sudbury Neutrino Observatory

    SciTech Connect

    Oblath, Noah [Center for Experimental Nuclear Physics and Astrophysics University of Washington, Seattle, WA (United States)

    2007-10-26

    The Sudbury Neutrino Observatory (SNO) is the first experiment to measure the total flux of active, high-energy neutrinos from the sun. Results from SNO have solved the long-standing 'Solar Neutrino Problem' by demonstrating that neutrinos change flavor. SNO measured the total neutrino flux with the neutral-current interaction of solar neutrinos with 1000 tonnes of D{sub 2}O. In the first two phases of the experiment we detected the neutron from that interaction by capture on deuterium and capture on chlorine, respectively. In the third phase an array of {sup 3}He proportional counters was deployed in the detector. This allows a measurement of the neutral-current neutrons that is independent of the Cherenkov light detected by the PMT array. We are currently developing a unique, detailed simulation of the current pulses from the proportional-counter array that will be used to help distinguish signal and background pulses.

  13. Global status of neutrino oscillation parameters after Neutrino-2012

    NASA Astrophysics Data System (ADS)

    Forero, D. V.; Tórtola, M.; Valle, J. W. F.

    2012-10-01

    Here we update the global fit of neutrino oscillations in Refs. [T. Schwetz, M. Tortola, and J. W. F. Valle, New J. Phys. 13, 063004 (2011); T. Schwetz, M. Tortola, and J. W. F. Valle, New J. Phys. 13, 109401 (2011)] including the recent measurements of reactor antineutrino disappearance reported by the Double Chooz, Daya Bay, and RENO experiments, together with latest MINOS and T2K appearance and disappearance results, as presented at the Neutrino-2012 conference. We find that the preferred global fit value of ?13 is quite large: sin?2?13?0.025 for normal and inverted neutrino mass ordering, with ?13=0 now excluded at more than 10?. The impact of the new ?13 measurements over the other neutrino oscillation parameters is discussed as well as the role of the new long-baseline neutrino data and the atmospheric neutrino analysis in the determination of a non-maximal atmospheric angle ?23.

  14. Measurement of atmospheric neutrino oscillations with the ANTARES neutrino telescope

    NASA Astrophysics Data System (ADS)

    Adrián-Martínez, S.; Al Samarai, I.; Albert, A.; André, M.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardid, M.; Astraatmadja, T.; Aubert, J.-J.; Baret, B.; Basa, S.; Bertin, V.; Biagi, S.; Bigongiari, C.; Bogazzi, C.; Bou-Cabo, M.; Bouhou, B.; Bouwhuis, M. C.; Brunner, J.; Busto, J.; Capone, A.; Cârloganu, C.; Carr, J.; Cecchini, S.; Charif, Z.; Charvis, Ph.; Chiarusi, T.; Circella, M.; Coniglione, R.; Core, L.; Costantini, H.; Coyle, P.; Creusot, A.; Curtil, C.; de Bonis, G.; Decowski, M. P.; Dekeyser, I.; Deschamps, A.; Distefano, C.; Donzaud, C.; Dornic, D.; Dorosti, Q.; Drouhin, D.; Eberl, T.; Emanuele, U.; Enzenhöfer, A.; Ernenwein, J.-P.; Escoffier, S.; Fehn, K.; Fermani, P.; Ferri, M.; Ferry, S.; Flaminio, V.; Folger, F.; Fritsch, U.; Fuda, J.-L.; Galatà, S.; Gay, P.; Geyer, K.; Giacomelli, G.; Giordano, V.; Gleixner, A.; Gómez-González, J. P.; Graf, K.; Guillard, G.; Hallewell, G.; Hamal, M.; van Haren, H.; Heijboer, A. J.; Hello, Y.; Hernández-Rey, J. J.; Herold, B.; Hößl, J.; Hsu, C. C.; de Jong, M.; Kadler, M.; Kalekin, O.; Kappes, A.; Katz, U.; Kavatsyuk, O.; Kooijman, P.; Kopper, C.; Kouchner, A.; Kreykenbohm, I.; Kulikovskiy, V.; Lahmann, R.; Lambard, G.; Larosa, G.; Lattuada, D.; Lefèvre, D.; Lim, G.; Lo Presti, D.; Loehner, H.; Loucatos, S.; Louis, F.; Mangano, S.; Marcelin, M.; Margiotta, A.; Martínez-Mora, J. A.; Meli, A.; Montaruli, T.; Morganti, M.; Moscoso, L.; Motz, H.; Neff, M.; Nezri, E.; Palioselitis, D.; P?v?la?, G. E.; Payet, K.; Petrovic, J.; Piattelli, P.; Popa, V.; Pradier, T.; Presani, E.; Racca, C.; Reed, C.; Riccobene, G.; Richardt, C.; Richter, R.; Rivière, C.; Robert, A.; Roensch, K.; Rostovtsev, A.; Ruiz-Rivas, J.; Rujoiu, M.; Russo, G. V.; Samtleben, D. F. E.; Sánchez-Losa, A.; Sapienza, P.; Schmid, J.; Schnabel, J.; Schöck, F.; Schuller, J.-P.; Schüssler, F.; Seitz, T.; Shanidze, R.; Simeone, F.; Spies, A.; Spurio, M.; Steijger, J. J. M.; Stolarczyk, Th.; Taiuti, M.; Tamburini, C.; Trovato, A.; Vallage, B.; Vallée, C.; van Elewyck, V.; Vecchi, M.; Vernin, P.; Visser, E.; Wagner, S.; Wijnker, G.; Wilms, J.; de Wolf, E.; Yepes, H.; Zaborov, D.; Zornoza, J. D.; Zúñiga, J.; ANTARES Collaboration

    2012-08-01

    The data taken with the ANTARES neutrino telescope from 2007 to 2010, a total live time of 863 days, are used to measure the oscillation parameters of atmospheric neutrinos. Muon tracks are reconstructed with energies as low as 20 GeV. Neutrino oscillations will cause a suppression of vertical upgoing muon neutrinos of such energies crossing the Earth. The parameters determining the oscillation of atmospheric neutrinos are extracted by fitting the event rate as a function of the ratio of the estimated neutrino energy and reconstructed flight path through the Earth. Measurement contours of the oscillation parameters in a two-flavour approximation are derived. Assuming maximal mixing, a mass difference of ?m322=(3.1±0.9)?10-3 eV is obtained, in good agreement with the world average value.

  15. Transformative A_4 Mixing of Neutrinos with CP Violation

    E-print Network

    Ernest Ma

    2015-04-14

    Given any real $3 \\times 3$ Majorana neutrino mass matrix, the application of a familiar $A_4$ transformation turns it into a well-known form, predicting $\\theta_{23} = \\pi/4$ and $\\delta_{CP} = \\pm \\pi/2$ with $\\theta_{13} \

  16. Global three-neutrino oscillation analysis of neutrino data

    Microsoft Academic Search

    M. C. Gonzalez-Garcia; M. Maltoni; C. Pena-Garay; J. W. F. Valle

    2001-01-01

    A global analysis of the solar, atmospheric and reactor neutrino data is\\u000apresented in terms of three-neutrino oscillations. We include the most recent\\u000asolar neutrino rates of Homestake, SAGE, GALLEX and GNO, as well as the recent\\u000a1117 day Super-Kamiokande data sample, including the recoil electron energy\\u000aspectrum both for day and night periods and we treat in a unified

  17. Non-unitary neutrino propagation from neutrino decay

    NASA Astrophysics Data System (ADS)

    Berryman, Jeffrey M.; de Gouvêa, André; Hernández, Daniel; Oliveira, Roberto L. N.

    2015-03-01

    Neutrino propagation in space-time is not constrained to be unitary if very light states - lighter than the active neutrinos - exist into which neutrinos may decay. If this is the case, neutrino flavor-change is governed by a handful of extra mixing and "oscillation" parameters, including new sources of CP-invariance violation. We compute the transition probabilities in the two- and three-flavor scenarios and discuss the different phenomenological consequences of the new physics. These are qualitatively different from other sources of unitarity violation discussed in the literature.

  18. Searching for hep Neutrinos using the Sudbury Neutrino Observatory

    E-print Network

    Howard, Chris

    2009-01-01

    The Sudbury Neutrino Observatory has recently finished its third and final phase, and has accumulated over 1082 days of neutrino data, spanning the energy range from approximately 5-20 MeV. Almost all the observed neutrinos are due to the 8B reaction in the Sun. The so-called hep process (3He + p -> 4He + e + nu_e) also occurs in the Sun, but has not yet been observed. hep neutrino energy endpoint extends above the 8B spectrum. This paper describes the three phase analysis that will ultimately be the most sensitive to this reaction.

  19. Solar Neutrino Data, Neutrino Magnetic Moments and Flavor Mixing

    E-print Network

    E. Kh. Akhmedov; A. Lanza; S. T. Petcov

    1994-11-15

    The results of all currently operating solar neutrino experiments are analyzed in the framework of the resonant neutrino spin--flavor precession scenario including the effects of neutrino mixing. Nine different profiles of the solar magnetic field are used in the calculations. It is shown that the available experimental data can be accounted for within the considered scenario. The Ga--Ge data lead to an upper limit on the neutrino mixing angle: $\\sin 2\\theta_0 \\aprle 0.25$. One can discriminate between small mixing angle ($\\sin 2\\theta_0 \\aprle 0.1$) and moderate mixing angle solutions by studying the solar $\\bar{\

  20. First Neutrino Observations from the Sudbury Neutrino Observatory

    NASA Astrophysics Data System (ADS)

    McDonald, A. B.; Boulay, M. G.; Bovin, E.; Chen, M.; Duncan, F. A.; Earle, E. D.; Evans, H. C.; Ewan, G. T.; Ford, R. J.; Hallin, A. L.; Harvey, P. J.; Hepburn, J. D.; Jillings, C.; Lee, H. W.; Leslie, J. R.; Mak, H. B.; McDonald, A. B.; McLatchie, W.; Moffat, B. A.; Robertson, B. C.; Skensved, P.; Sur, B.; Blevis, I.; Dalnoki-Veress, F.; Davidson, W.; Farine, J.; Grant, D. R.; Hargrove, C. K.; Levine, I.; McFarlane, K.; Noble, T.; Novikov, V. M.; O'Neill, M.; Shatkay, M.; Shewchuk, C.; Sinclair, D.; Andersen, T.; Chon, M. C.; Jagam, P.; Law, J.; Lawson, I. T.; Ollerhead, R. W.; Simpson, J. J.; Tagg, N.; Wang, J. X.; Bigu, J.; Cowan, J. H. M.; Hallman, E. D.; Haq, R. U.; Hewett, J.; Hykawy, J. G.; Jonkmans, G.; Roberge, A.; Saettler, E.; Schwendener, M. H.; Seifert, H.; Tafirout, R.; Virtue, C. J.; Gil, S.; Heise, J.; Helmer, R.; Komar, R. J.; Kutter, T.; Nally, C. W.; Ng, H. S.; Schubank, R.; Tserkovnyak, Y.; Waltham, C. E.; Beier, E. W.; Cowen, D. F.; Frank, E. D.; Frati, W.; Keener, P. T.; Klein, J. R.; Kyba, C.; McDonald, D. S.; Neubauer, M. S.; Newcomer, F. M.; Rusu, V.; Van Berg, R.; Van de Water, R. G.; Wittich, P.; Bowles, T. J.; Brice, S. J.; Dragowsky, M.; Fowler, M. M.; Goldschmidt, A.; Hamer, A.; Hime, A.; Kirch, K.; Wilhelmy, J. B.; Wouters, J. M.; Chan, Y. D.; Chen, X.; Isaac, M. C. P.; Lesko, K. T.; Marino, A. D.; Norman, E. B.; Okada, C. E.; Poon, A. W. P.; Smith, A. R.; Schuelke, A.; Stokstad, R. G.; Ahmad, Q. R.; Browne, M. C.; Bullard, T. V.; Doe, P. J.; Duba, C. A.; Elliott, S. R.; Fardon, R.; Germani, J. V.; Hamian, A. A.; Heeger, K. M.; Drees, R. Meijer; Orrell, J.; Robertson, R. G. H.; Schaffer, K.; Smith, M. W. E.; Steiger, T. D.; Wilkerson, J. F.; Barton, J. C.; Biller, S.; Black, R.; Boardman, R.; Bowler, M.; Cameron, J.; Cleveland, B.; Doucas, G.; Ferraris; Fergami, H.; Frame, K.; Heron, H.; Howard, C.; Jelley, N. A.; Knox, A. B.; Lay, M.; Locke, W.; Lyon, J.; McCaulay, N.; Majerus, S.; MacGregor, G.; Moorhead, M.; Omori, M.; Tanner, N. W.; Taplin, R.; Thorman, M.; Trent, P. T.; Wark, D. L.; West, N.; Boger, J.; Hahn, R. L.; Rowley, J. K.; Yeh, M.; Allen, R. G.; Buhler, G.; Chen, H. H.

    The first neutrino observations from the Sudbury Neutrino Observatory are presented from preliminary analyses. Based on energy, direction and location, the data in the region of interest appear to be dominated by 8B solar neutrinos, detected by the charged current reaction on deuterium and elastic scattering from electrons, with very little background. Measurements of radioactive backgrounds indicate that the measurement of all active neutrino types via the neutral current reaction on deuterium will be possible with small systematic uncertainties. Quantitative results for the fluxes observed with these reactions will be provided when further calibrations have been completed.

  1. Homestake result, sterile neutrinos and low energy solar neutrino experiments

    E-print Network

    P. C. de Holanda; A. Yu. Smirnov

    2004-03-29

    The Homestake result is about ~ 2 \\sigma lower than the Ar-production rate, Q_{Ar}, predicted by the LMA MSW solution of the solar neutrino problem. Also there is no apparent upturn of the energy spectrum (R \\equiv N_{obs}/N_{SSM}) at low energies in SNO and Super-Kamiokande. Both these facts can be explained if a light, \\Delta m^2_{01} ~ (0.2 - 2) \\cdot 10^{-5} eV^2, sterile neutrino exists which mixes very weakly with active neutrinos: \\sin^2 2\\alpha ~ (10^{-5} - 10^{-3}). We perform both the analytical and numerical study of the conversion effects in the system of two active neutrinos with the LMA parameters and one weakly mixed sterile neutrino. The presence of sterile neutrino leads to a dip in the survival probability in the intermediate energy range E = (0.5 - 5) MeV thus suppressing the Be, or/and pep, CNO as well as B electron neutrino fluxes. Apart from diminishing Q_{Ar} it leads to decrease of the Ge-production rate and may lead to decrease of the BOREXINO signal and CC/NC ratio at SNO. Future studies of the solar neutrinos by SNO, SK, BOREXINO and KamLAND as well as by the new low energy experiments will allow us to check this possibility. We present a general analysis of modifications of the LMA energy profile due to mixing with new neutrino states.

  2. Non-unitary neutrino propagation from neutrino decay

    DOE PAGESBeta

    Berryman, Jeffrey M.; de Gouvêa, André; Hernández, Daniel; Oliveira, Roberto L.N.

    2015-03-01

    Neutrino propagation in space–time is not constrained to be unitary if very light states – lighter than the active neutrinos – exist into which neutrinos may decay. If this is the case, neutrino flavor-change is governed by a handful of extra mixing and “oscillation” parameters, including new sources of CP-invariance violation. We compute the transition probabilities in the two- and three-flavor scenarios and discuss the different phenomenological consequences of the new physics. These are qualitatively different from other sources of unitarity violation discussed in the literature.

  3. Searching for hep Neutrinos using the Sudbury Neutrino Observatory

    E-print Network

    Chris Howard; for the SNO Collaboration

    2009-05-29

    The Sudbury Neutrino Observatory has recently finished its third and final phase, and has accumulated over 1082 days of neutrino data, spanning the energy range from approximately 5-20 MeV. Almost all the observed neutrinos are due to the 8B reaction in the Sun. The so-called hep process (3He + p -> 4He + e + nu_e) also occurs in the Sun, but has not yet been observed. hep neutrino energy endpoint extends above the 8B spectrum. This paper describes the three phase analysis that will ultimately be the most sensitive to this reaction.

  4. Solar neutrino experiments: An update

    SciTech Connect

    Hahn, R.L.

    1993-12-31

    The situation in solar neutrino physics has changed drastically in the past few years, so that now there are four neutrino experiments in operation, using different methods to look at different regions of the solar neutrino energy spectrum. These experiments are the radiochemical {sup 37}Cl Homestake detector, the realtime Kamiokande detector, and the different forms of radiochemical {sup 71}Ga detectors used in the GALLEX and SAGE projects. It is noteworthy that all of these experiments report a deficit of observed neutrinos relative to the predictions of standard solar models (although in the case of the gallium detectors, the statistical errors are still relatively large). This paper reviews the basic principles of operation of these neutrino detectors, reports their latest results and discusses some theoretical interpretations. The progress of three realtime neutrino detectors that are currently under construction, SuperKamiok, SNO and Borexino, is also discussed.

  5. Unparticle physics and neutrino phenomenology

    SciTech Connect

    Barranco, J.; Bolanos, A.; Miranda, O. G.; Moura, C. A.; Rashba, T. I. [Max-Planck-Institut fuer Gravitationsphysik (Albert-Einstein-Institut), Am Muehlenberg 1, D-14476 Golm (Germany); Departamento de Fisica, Centro de Investigacion y de Estudios Avanzados del IPN, Apartado Postal 14-740 07000 Mexico, D F (Mexico); INFN Sezione di Napoli, Complesso Universitario Monte S. Angelo, Via Cintia, I-80126 Napoli (Italy); Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, 80805 Muenchen (Germany) and Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation of the Russian Academy of Sciences, 142190, Troitsk, Moscow region (Russian Federation)

    2009-04-01

    We have constrained unparticle interactions with neutrinos and electrons using available data on neutrino-electron elastic scattering and the four CERN LEP experiments data on mono photon production. We have found that, for neutrino-electron elastic scattering, the MUNU experiment gives better constraints than previous reported limits in the region d>1.5. The results are compared with the current astrophysical limits, pointing out the cases where these limits may or may not apply. We also discuss the sensitivity of future experiments to unparticle physics. In particular, we show that the measurement of coherent reactor neutrino scattering off nuclei could provide a good sensitivity to the couplings of unparticle interaction with neutrinos and quarks. We also discuss the case of future neutrino-electron experiments as well as the International Linear Collider.

  6. Burst Neutrinos from Nitrogen Flash

    E-print Network

    A. M. Serenelli; M. Fukugita

    2005-09-07

    Neutrinos give a novel probe to explore deep interior of astrophysical objects, which otherwise is not accessible with optical observations; among notable examples are solar and supernova neutrinos. We show that there is a new class of strong neutrino emission from helium burning, N + alpha --> 18F gamma followed by beta decay 18F --> 18O + e+ + nu_e, that gives a maximum neutrino luminosity of 10^8 times the solar bolometric luminosity at the helium-core flash of a 1 M_sun star, whereas the flash is not observable by optical means. This means that the neutrino flux, of average energy of 0.382 MeV, will be 10% the solar CNO neutrino flux on Earth if the star is located at 10pc.

  7. Some Novel Ways for Neutrino Mass Generation

    E-print Network

    Mavromatos, Nick E

    2015-01-01

    I discuss dynamical generation of neutrino masses in unconventional scenarios where the background space-time geometry plays a crucial role. I discuss two types of backgrounds: (i) Lorentz Violating and (ii) Geometries with Torsion. In the former case, the violation of Lorentz symmetry, at a scale M, may be viewed as a catalyst for mass generation and induced flavour oscillations among neutrino species, which survive the limit of M taken to infinity, leading to a hierarchy among neutrino masses. In the latter case, the (totally antisymmetric components of the) torsion degrees of freedom correspond to a pseudoscalar axion field in four space-time dimensions. This field is assumed to be mixed, through non-diagonal kinetic terms, with ordinary axion fields that may exist in the theory for other reasons and couple to neutrinos with chirality changing Yukawa couplings. The torsion-ordinary-axion-field mixing is responsible, through higher-loop anomalous graphs, for the dynamical generation of Majorana masses. The ...

  8. Neutrino Masses from Large Extra Dimensions

    SciTech Connect

    Arkani-Hamed, Nima

    1998-11-24

    Recently it was proposed that the standard model (SM) degrees of freedom reside on a (3 + 1)-dimensional wall or ''3-brane'' embedded in a higher-dimensional spacetime. Furthermore, in this picture it is possible for the fundamental Planck mass M* to be as small as the weak scale M* approximate or equal to O(TeV) and the observed weakness of gravity at long distances is due the existence of new sub-millimeter spatial dimensions. We show that in this picture it is natural to expect neutrino masses to occur in the 10{sup {minus}1} - 10{sup {minus}4} eV range, despite the lack of any fundamental scale higher than M*. Such suppressed neutrino masses are not the result of a see-saw, but have intrinsically higher-dimensional explanations. We explore two possibilities. The first mechanism identifies any massless bulk fermions as right-handed neutrinos. These give naturally small Dirac masses for the same reason that gravity is weak at long distances in this framework. The second mechanism takes advantage of the large infrared desert: the space in the extra dimensions. Here, small Majorana neutrino masses are generated by breaking lepton number on distant branes.

  9. Pseudo-Dirac Neutrinos in the New Standard Model

    E-print Network

    Andre de Gouvea; Wei-Chih Huang; James Jenkins

    2009-06-28

    The addition of gauge singlet fermions to the Standard Model Lagrangian renders the neutrinos massive and allows one to explain all that is experimentally known about neutrino masses and lepton mixing by varying the values of the Majorana mass parameters M for the gauge singlets and the neutrino Yukawa couplings. Here we explore the region of parameter space where M values are much smaller than the neutrino Dirac masses. In this region, neutrinos are pseudo-Dirac fermions. We find that current solar data constrain M values to be less than at least 1E-9 eV, and discuss the sensitivity of future experiments to tiny gauge singlet fermion masses. We also discuss a useful basis for analyzing pseudo-Dirac neutrino mixing effects. In particular, we identify a simple relationship between elements of M and the induced enlarged mixing matrix and new mass-squared differences. These allow one to directly relate bounds on the new mass-squared differences to bounds on the singlet fermion Majorana masses.

  10. Spin flip of neutrinos with magnetic moment in core-collapse supernova

    E-print Network

    Oleg Lychkovskiy; Sergei Blinnikov

    2009-08-19

    Neutrino with magnetic moment can experience a chirality flip while scattering off charged particles. This effect may lead to important consequences for the dynamics and the neutrino signal of the core-collapse supernova. It is known that if neutrino is a Dirac fermion, then nu_L->nu_R transition induced by the chirality flip leads to the emission of sterile right-handed neutrinos. The typical energies of these neutrinos are rather high, E ~ (100-200)MeV. Neutrino spin precession in the magnetic field either inside the collapsing star or in the interstellar space may lead to the backward transition, nu_R->nu_L. Both possibilities are known to be interesting. In the former case high-energy neutrinos can deliver additional energy to the supernova envelope, which can help the supernova to explode. In the latter case high-energy neutrinos may be detected simultaneously with the "normal" supernova neutrino signal, which would be a smoking gun for the Dirac neutrino magnetic moment. We report the results of the calculation of the supernova right-handed neutrino luminosity up to 250 ms after bounce. They allow to refine the estimates of the energy emitted in right-handed neutrinos. Also the sensitivity of water Cherenkov detectors to the Dirac neutrino magnetic moment is estimated. For mu_Dirac=10^{-13}mu_B Super-Kamiokande is expected to detect at least few high-energy events from a galactic supernova explosion. Also we briefly discuss the case of Majorana neutrino magnetic moment. It is pointed out that spin flips may quickly equilibrate electron neutrinos with non-electron antineutrinos if mu_Majorana~10^{-12}mu_B. This may lead to various consequences for supernova physics.

  11. Astrophysical and cosmological constraints to neutrino properties

    NASA Technical Reports Server (NTRS)

    Kolb, Edward W.; Schramm, David N.; Turner, Michael S.

    1989-01-01

    The astrophysical and cosmological constraints on neutrino properties (masses, lifetimes, numbers of flavors, etc.) are reviewed. The freeze out of neutrinos in the early Universe are discussed and then the cosmological limits on masses for stable neutrinos are derived. The freeze out argument coupled with observational limits is then used to constrain decaying neutrinos as well. The limits to neutrino properties which follow from SN1987A are then reviewed. The constraint from the big bang nucleosynthesis on the number of neutrino flavors is also considered. Astrophysical constraints on neutrino-mixing as well as future observations of relevance to neutrino physics are briefly discussed.

  12. Neutrino Opacities in Nuclear Matter

    E-print Network

    Adam Burrows; Sanjay Reddy; Todd A. Thompson

    2004-04-21

    Neutrino-matter cross sections and interaction rates are central to the core-collapse supernova phenomenon and, very likely, to the viability of the explosion mechanism itself. In this paper, we describe the major neutrino scattering, absorption, and production processes that together influence the outcome of core collapse and the cooling of protoneutron stars. One focus is on energy redistribution and many-body physics, but our major goal is to provide a useful resource for those interested in supernova neutrino microphysics.

  13. Future of Neutrino Interaction Models

    NASA Astrophysics Data System (ADS)

    Terri, Ryan

    2015-04-01

    Neutrino-nucleus cross sections are one of the dominant sources of systematic errors in long-baseline neutrino oscillation experiments. To achieve the goals of precision measurements of the mixing angles and difference of the mass eigenstates squared, and discover the mass hierarchy and CP-violating phase, the underlying neutrino interactions must be better understood. This poster will mention some recent improvements in models in the interaction generators as well as some possible future improvements for proposed experiments.

  14. Muon colliders and neutrino factories

    SciTech Connect

    Geer, S.; /Fermilab

    2010-09-01

    Over the last decade there has been significant progress in developing the concepts and technologies needed to produce, capture and accelerate {Omicron}(10{sup 21}) muons/year. This development prepares the way for a new type of neutrino source (Neutrino Factory) and a new type of very high energy lepton-antilepton collider (Muon Collider). This article reviews the motivation, design and R&D for Neutrino Factories and Muon Colliders.

  15. Solar neutrinos: theory vs experiment

    SciTech Connect

    Haxton, W.C.

    1991-01-01

    I review the standard solar model, the disparities between its predictions and the solar neutrino flux measurements of the Homestake and Kamioka II collaborations, and possible particle physics resolutions of this puzzle. The effects of matter, including density fluctuations and turbulence, on solar neutrino oscillations are reviewed, including possibilities for generating time variations in the solar neutrino flux. Finally, I consider possible outcomes and implications of the SAGE/GALLEX gallium experiments.

  16. Solar neutrinos: theory vs experiment

    SciTech Connect

    Haxton, W.C.

    1991-12-31

    I review the standard solar model, the disparities between its predictions and the solar neutrino flux measurements of the Homestake and Kamioka II collaborations, and possible particle physics resolutions of this puzzle. The effects of matter, including density fluctuations and turbulence, on solar neutrino oscillations are reviewed, including possibilities for generating time variations in the solar neutrino flux. Finally, I consider possible outcomes and implications of the SAGE/GALLEX gallium experiments.

  17. Neutrino masses and flavor mixing

    NASA Astrophysics Data System (ADS)

    Fritzsch, Harald

    2015-05-01

    We discuss the neutrino oscillations, using texture zero mass matrices for the leptons. The reactor mixing angle ?l is calculated. The ratio of the masses of two neutrinos is determined by the solar mixing angle. We can calculate the masses of the three neutrinos: m1 ? 0.003 eV, m2 ? 0.012 eV, m3 ? 0.048 eV.

  18. Neutrino Mixing from ?(6n2) Groups

    NASA Astrophysics Data System (ADS)

    Neder, Thomas

    2015-04-01

    Experimentally viable lepton mixing parameters can be predicted in so-called direct flavour models with Majorana neutrinos using ?(6n2) groups as a flavour group. In direct models, in which the flavour group is broken to a Z2 × Z2 subgroup in the neutrino sector, mixing angles and Dirac CP phase are purely predicted from symmetry. General predictions of direct models with ?(6n2) flavour groups are that all mixing angles are fixed up to a discrete choice and that the Dirac CP phase is 0 or ? Furthermore, the middle column of the mixing matrix is trimaximal which yields the sum rule ?23 = 45° ± ?13/?2 depending on the Dirac phase. These predictions of lepton mixing parameters are compatible with recent global fit results or will be tested experimentally in the near future. It is the first time that such predictions have been obtained model-independently for an infinite series of groups.

  19. Small neutrino mass from large compactification volumes.

    PubMed

    Conlon, Joseph P; Cremades, Daniel

    2007-07-27

    We present an argument in which the scale approximately 0.1 eV associated with neutrino masses naturally appears in a class of (very) large volume compactifications, being tied to a supersymmetry scale of 10(3) GeV and a string scale of 10(11) GeV. The masses are of the Majorana type, and there is no right-handed neutrino within the low-energy field theory. The suppression scale 10(14) GeV is independent of the masses of the heavy states that are integrated out. These kinds of constructions appear naturally in type IIB flux compactifications. However, the arguments that lead to this result rely only on a few geometrical features of the compactification manifold and, hence, can be used independently of string theory. PMID:17678352

  20. Magnus approximation in neutrino oscillations

    NASA Astrophysics Data System (ADS)

    Acero, Mario A.; Aguilar-Arevalo, Alexis A.; D'Olivo, J. C.

    2011-04-01

    Oscillations between active and sterile neutrinos remain as an open possibility to explain some anomalous experimental observations. In a four-neutrino (three active plus one sterile) mixing scheme, we use the Magnus expansion of the evolution operator to study the evolution of neutrino flavor amplitudes within the Earth. We apply this formalism to calculate the transition probabilities from active to sterile neutrinos with energies of the order of a few GeV, taking into account the matter effect for a varying terrestrial density.

  1. Magnetic Dipole Moment of Neutrino

    E-print Network

    Masood, Samina S

    2015-01-01

    We recalculate the magnetic moment of neutrinos in a hot and dense medium. The magnetic dipole moment of neutrinos is modified at high temperature and chemical potential. We show that the magnetic dipole moment of electron neutrino does not get a significant contribution from thermal background to meet the cosmological bound. However, chemical potential contribution to the magnetic moment is non-ignorable even when chemical potential is an order of magnitude greater than the electron mass. It is demonstrated that this effect is more significant in the models with an extended Higgs sector through neutrino mixing.

  2. Magnetic Dipole Moment of Neutrino

    E-print Network

    Samina S. Masood

    2015-06-03

    We recalculate the magnetic moment of neutrinos in a hot and dense medium. The magnetic dipole moment of neutrinos is modified at high temperature and chemical potential. We show that the magnetic dipole moment of electron neutrino does not get a significant contribution from thermal background to meet the cosmological bound. However, chemical potential contribution to the magnetic moment is non-ignorable even when chemical potential is an order of magnitude greater than the electron mass. It is demonstrated that this effect is more significant in the models with an extended Higgs sector through neutrino mixing.

  3. Neutrino clouds and dark matter

    SciTech Connect

    Goldman, T. [Los Alamos National Lab., NM (United States); McKellar, B.H.J. [Melbourne Univ., Parkville, VIC (Australia); Stephenson, G.J. Jr. [New Mexico Univ., Albuquerque, NM (United States)

    1996-12-31

    We have examined the consequences of assuming the existence of a light scalar boson, weakly coupled to neutrinos, and not coupled to any other light fermions. For a range of parameters, we find that this hypothesis leads to the development of neutrino clusters which form in the early Universe and which provide gravitational fluctuations on scales small compared to a parsec (i.e., the scale of solar systems). Under some conditions, this can produce anomalous gravitational acceleration within solar systems and lead to a vanishing of neutrino mass-squared differences, giving rise to strong neutrino oscillation effects.

  4. Double-Chooz Neutrino Experiment

    E-print Network

    C. Palomares

    2009-11-17

    The Double Chooz experiment will use the electron antineutrinos produced by the Chooz nuclear power station to search for a non-vanishing value of the Theta_13 neutrino mixing angle. Double Chooz will be the first of a new generation of neutrino experiments using identical detectors at different distances from the neutrino source to reduce the systematic errors due to the uncertainties on the neutrino flux and to the detector acceptance. The far detector is expected to be operative by the beginning of 2010. Installation of the near detector will occur in 2010.

  5. Supernova neutrinos and explosive nucleosynthesis

    NASA Astrophysics Data System (ADS)

    Kajino, T.; Aoki, W.; Cheoun, M.-K.; Hayakawa, T.; Hidaka, J.; Hirai, Y.; Mathews, G. J.; Nakamura, K.; Shibagaki, S.; Suzuki, T.

    2014-05-01

    Core-collapse supernovae eject huge amount of flux of energetic neutrinos. We studied the explosive nucleosyn-thesis in supernovae and found that several isotopes 7Li, 11B, 92Nb, 138La and 180Ta as well as r-process nuclei are affected by the neutrino interactions. The abundance of these isotopes therefore depends strongly on the neutrino flavor oscillation due to the Mikheyev-Smirnov-Wolfenstein (MSW) effect. We discuss first how to determine the neutrino temperatures in order to explain the observed solar system abundances of these isotopes, combined with Galactic chemical evolution of the light nuclei and the heavy r-process elements. We then study the effects of neutrino oscillation on their abundances, and propose a novel method to determine the still unknown neutrino oscillation parameters, mass hierarchy and ?13, simultaneously. There is recent evidence that SiC X grains from the Murchison meteorite may contain supernova-produced light elements 11B and 7Li encapsulated in the presolar grains. Combining the recent experimental constraints on ?13, we show that our method sug-gests at a marginal preference for an inverted neutrino mass hierarchy. Finally, we discuss supernova relic neutrinos that may indicate the softness of the equation of state (EoS) of nuclear matter as well as adiabatic conditions of the neutrino oscillation.

  6. Analytically expressed constraint on two Majorana phases in neutrinoless double beta decay

    E-print Network

    Maedan, Shinji

    2014-01-01

    We assume that neutrinoless double beta decay is caused by the exchange of three light Majorana neutrinos. Under this assumption, we obtain, by the method of perturbation, the equation representing the isocontour of effective Majorana mass which is the function of two CP-violating Majorana phases. The equation representing the isocontour (constraint equation between two Majorana phases) is expressed analytically by six parameters: two lepton mixing angles, two kinds of neutrino mass squared differences, lightest neutrino mass scale, and the effective Majorana mass. We discuss how the constraint equation between two Majorana phases changes when the lightest neutrino mass scale is varied.

  7. Radiochemical solar neutrino experiments

    Microsoft Academic Search

    V. N. Gavrin; B. T. Cleveland

    2007-01-01

    Radiochemical experiments have been crucial to solar neutrino research. Even\\u000atoday, they provide the only direct measurement of the rate of the\\u000aproton-proton fusion reaction, p + p --> d + e^+ + nu_e, which generates most\\u000aof the Sun's energy. We first give a little history of radiochemical solar\\u000aneutrino experiments with emphasis on the gallium experiment SAGE --

  8. Entanglement of neutrino states

    E-print Network

    D. L. Khokhlov

    2008-11-12

    Muon and muon antineutrino born in the decay of charged pion form the entangled spin state. The decay of muon with the left helicity triggers the left helicity for muon antineutrino to preserve the null total angular momentum of muon and muon antineutrino. This is forbidden for antineutrino hence one cannot detect the muon antineutrino after the decay of muon. This effect may explain the deficit of muon neutrino flux in the Super-Kamiokande, K2K, MINOS experiments.

  9. Birth of Neutrino Astrophysics

    ScienceCinema

    None

    2011-10-06

    Based mainly on the results of two experiments, KamiokaNDE and Super-KamiokaNDE, the birth of neutrino astrophysics will be described. At the end, the result of the third generation Kamioka experiment, KamLAND, will be discussed together with the future possibilities.Organiser(s): Daniel Treille / EP DivisionNote: * Tea & coffee will be served at 16:00 hrs. Please note unusual day.

  10. Confronting Four Zero Neutrino Yukawa Textures with $N_2^{}$-dominated Leptogenesis

    E-print Network

    Zhang, Jue

    2015-01-01

    We consider a restricted Type-I seesaw scenario with four texture zeros in the neutrino Yukawa matrix, in the basis where both the charged-lepton Yukawa matrix and the Majorana mass matrix for right-handed neutrinos are diagonal. Inspired by grand unified theories, we further require the neutrino Yukawa matrix to exhibit a similar hierarchical pattern to that in the up-type quark Yukawa matrix. With such a hierarchy requirement, we find that leptogenesis, which would operate in a $N_2^{}$-dominated scenario with the asymmetry generated by the next-to-lightest right-handed neutrino $N_2^{}$, can greatly reduce the number of allowed textures, and disfavors the scenario that three light neutrinos are quasi-degenerate. Such a quasi-degenerate scenario of light neutrinos may soon be tested in upcoming neutrino experiments.

  11. Neutrino Geophysics Conference Introduction

    NASA Astrophysics Data System (ADS)

    Learned, John G.; Dye, Stephen T.; Pakvasa, Sandip

    2006-12-01

    Long distance detection of electron anti-neutrinos from reactors at distances of order 200 km has been achieved with the 1000 ton liquid scintillator-based KamLAND instrument in Japan. In summer 2005 the KamLAND group reported the first detection of anti-neutrinos from the natural radioactivity of the earth. These measurements are due to uranium and thorium decays dominantly from the nearby crust in Japan, and are expected to have only a small contribution from the earth’s mantle (and core). Several new detectors are under consideration around the world for measurements which when taken together can reveal the location of these heavy elements, which are expected to contribute a major share of the internal earth’s heating via their radioactivity. This heating is of course associated with providing the power to drive the geomagnetic field and plate tectonics. Geologists have only indirect evidence about the deep earth, mostly from seismic wave velocity and inferences from a few meteorites. Anti-neutrino detection, on the other hand, yields direct information about earth’s interior. The location and magnitude of the earth’s uranium and thorium are crucial to understanding the origin and evolution of the earth and present day activity.

  12. Boxing with neutrino oscillations

    NASA Astrophysics Data System (ADS)

    Wagner, D. J.; Weiler, Thomas J.

    1999-06-01

    We develop a characterization of neutrino oscillations based on the coefficients of the oscillating terms. These coefficients are individually observable; although they are quartic in the elements of the unitary mixing matrix, they are independent of the conventions chosen for the angle and phase parametrization of the mixing matrix. We call these reparametrization-invariant observables ``boxes'' because of their geometric relation to the mixing matrix, and because of their association with the Feynman box diagram that describes oscillations in field theory. The real parts of the boxes are the coefficients for the CP- or T-even oscillation modes, while the imaginary parts are the coefficients for the CP- or T-odd oscillation modes. Oscillation probabilities are linear in the boxes, so measurements can straightforwardly determine values for the boxes (which can then be manipulated to yield magnitudes of mixing matrix elements). We examine the effects of unitarity on the boxes and discuss the reduction of the number of boxes to a minimum basis set. For the three-generation case, we explicitly construct the basis. Using the box algebra, we show that CP violation may be inferred from measurements of neutrino flavor mixing even when the oscillatory factors have averaged. The framework presented here will facilitate general analyses of neutrino oscillations among n>=3 flavors.

  13. Boxing with neutrino oscillations

    SciTech Connect

    Wagner, D.J. [Department of Physics and Astronomy, Vanderbilt University, Box 1807 B, Nashville, Tennessee 37235 (United States)] [Department of Physics and Astronomy, Vanderbilt University, Box 1807 B, Nashville, Tennessee 37235 (United States); [Department of Physics, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States); Weiler, T.J. [Department of Physics and Astronomy, Vanderbilt University, Box 1807 B, Nashville, Tennessee 37235 (United States)] [Department of Physics and Astronomy, Vanderbilt University, Box 1807 B, Nashville, Tennessee 37235 (United States)

    1999-06-01

    We develop a characterization of neutrino oscillations based on the coefficients of the oscillating terms. These coefficients are individually observable; although they are quartic in the elements of the unitary mixing matrix, they are independent of the conventions chosen for the angle and phase parametrization of the mixing matrix. We call these reparametrization-invariant observables {open_quotes}boxes{close_quotes} because of their geometric relation to the mixing matrix, and because of their association with the Feynman box diagram that describes oscillations in field theory. The real parts of the boxes are the coefficients for the {ital CP}- or {ital T}-even oscillation modes, while the imaginary parts are the coefficients for the {ital CP}- or {ital T}-odd oscillation modes. Oscillation probabilities are linear in the boxes, so measurements can straightforwardly determine values for the boxes (which can then be manipulated to yield magnitudes of mixing matrix elements). We examine the effects of unitarity on the boxes and discuss the reduction of the number of boxes to a minimum basis set. For the three-generation case, we explicitly construct the basis. Using the box algebra, we show that {ital CP} violation may be inferred from measurements of neutrino flavor mixing even when the oscillatory factors have averaged. The framework presented here will facilitate general analyses of neutrino oscillations among n{ge}3 flavors. {copyright} {ital 1999} {ital The American Physical Society}

  14. Neutrino physics at LAMPF

    SciTech Connect

    Garvey, G.T.

    1989-01-01

    There are three neutrino experiments at LAMPF in various stages of completion or development. E225, the study of electron-neutrino electron scattering, which completed data taking in December 1986 and has just about completed all its analysis. E645, a search for /bar /nu///sub ..mu../ ..-->.. /bar /nu///sub e/ oscillation, is in its third and final year of data taking. The Large Cerenkov Detector (LCD), associated with E1015, has undergone extensive scientific and technical review and we are presently trying to obtain the necessary funds to build the detector, beam line, and target. In the following, each of these experiments will be briefly discussed. Before doing so, it is useful to show the characteristics of the neutrino spectrum resulting from the decay of ..pi../sup +/ at rest. It is also useful to realize that, on average, an 800-MeV proton from LAMPF produces about 0.1 ..pi../sup +/ decaying at rest. 16 refs., 5 figs., 4 tabs.

  15. On solutions of the standard-model Lagrangian with a Majorana mass term

    E-print Network

    R. Plaga

    2007-06-26

    It is demonstrated that the standard-model Lagrangian with a Majorana mass term for the neutrino admits no non-trivial solution. Because the standard model is generally believed to describe the gauge interactions of neutrinos correctly, the Majorana mass term must vanish and thus cannot enable neutrino-less double beta decay. More generally, neutrinos with standard-model gauge interactions cannot be Majorana fields. Historical reasons why this conclusion has not been drawn earlier are analyzed.

  16. Neutrino self-energy operator and neutrino magnetic moment

    SciTech Connect

    Dobrynina, A. A., E-mail: elenan@uniyar.ac.ru; Mikheev, N. V.; Narynskaya, E. N. [Yaroslavl State University (Russian Federation)] [Yaroslavl State University (Russian Federation)

    2013-11-15

    A simple method for calculating the magnetic moment of a massive neutrino on the basis of its self-energy operator is presented. An expression for the magnetic moment of a massive neutrino in an external electromagnetic field is obtained in the R{sub {xi}} gauge for the case of an arbitrary ratio of the lepton and W-boson masses.

  17. Neutrino-oscillatie en het Mobauer neutrino experiment

    E-print Network

    van Suijlekom, Walter

    flavour zouden kunnen veranderen, maar pas in 1968 werd de eerste experi- mentele aanwijzing in deze's door de zon uit- gestraald worden dan verwacht werd op basis van het Standaard Zonnemodel. Dit zou in µ- en -neutrino's. In 2001 werd door het Sudbury Neutrino Observatory vastgesteld dat de

  18. ON SOLAR NEUTRINO PROBLEM TIAN MA AND SHOUHONG WANG

    E-print Network

    ON SOLAR NEUTRINO PROBLEM TIAN MA AND SHOUHONG WANG Abstract. The current neutrino oscillation an alternative resolution to the solar neutrino loss problem. Contents 1. Introduction 1 2. Discrepancy of Solar, there are three flavors of neutrinos: the electron neutrino e, the tau neutrino and the mu neutrino µ. The solar

  19. Majorana and Condensed Matter Physics

    E-print Network

    Frank Wilczek

    2014-04-02

    Ettore Majorana contributed several ideas that have had significant, lasting impact in condensed matter physics, broadly construed. Here I will discuss, from a modern perspective, four important topics that have deep roots in Majorana's work: 1. Spin Response and Universal Connection; 2. Level Crossing and Generalized Laplace Transform; 3. Majorana Fermions, From Neutrinos to Electrons; 4. Majorinos and Emergent Symmetry.

  20. Detecting non-relativistic cosmic neutrinos by capture on tritium: phenomenology and physics potential

    NASA Astrophysics Data System (ADS)

    Long, Andrew J.; Lunardini, Cecilia; Sabancilar, Eray

    2014-08-01

    We study the physics potential of the detection of the Cosmic Neutrino Background via neutrino capture on tritium, taking the proposed PTOLEMY experiment as a case study. With the projected energy resolution of ? ~ 0.15 eV, the experiment will be sensitive to neutrino masses with degenerate spectrum, m1 simeq m2 simeq m3 = m? gtrsim 0.1 eV. These neutrinos are non-relativistic today; detecting them would be a unique opportunity to probe this unexplored kinematical regime. The signature of neutrino capture is a peak in the electron spectrum that is displaced by 2 m? above the beta decay endpoint. The signal would exceed the background from beta decay if the energy resolution is ? lesssim 0.7 m? . Interestingly, the total capture rate depends on the origin of the neutrino mass, being ?D simeq 4 and ?M simeq 8 events per year (for a 100 g tritium target) for unclustered Dirac and Majorana neutrinos, respectively. An enhancement of the rate of up to Script O(1) is expected due to gravitational clustering, with the unique potential to probe the local overdensity of neutrinos. Turning to more exotic neutrino physics, PTOLEMY could be sensitive to a lepton asymmetry, and reveal the eV-scale sterile neutrino that is favored by short baseline oscillation searches. The experiment would also be sensitive to a neutrino lifetime on the order of the age of the universe and break the degeneracy between neutrino mass and lifetime which affects existing bounds.

  1. Probing the seesaw mechanism with neutrino data and leptogenesis

    E-print Network

    Evgeny Kh. Akhmedov; Michele Frigerio; Alexei Yu. Smirnov

    2003-09-17

    In the framework of the seesaw mechanism with three heavy right-handed Majorana neutrinos and no Higgs triplets we carry out a systematic study of the structure of the right-handed neutrino sector. Using the current low-energy neutrino data as an input and assuming hierarchical Dirac-type neutrino masses $m_{Di}$, we calculate the masses $M_i$ and the mixing of the heavy neutrinos. We confront the inferred properties of these neutrinos with the constraints coming from the requirement of a successful baryogenesis via leptogenesis. In the generic case the masses of the right-handed neutrinos are highly hierarchical: $M_i \\propto m_{Di}^2$; the lightest mass is $M_1 \\approx 10^3 - 10^6$ GeV and the generated baryon-to-photon ratio $\\eta_B\\lesssim 10^{-14}$ is much smaller than the observed value. We find the special cases which correspond to the level crossing points, with maximal mixing between two quasi-degenerate right-handed neutrinos. Two level crossing conditions are obtained: ${m}_{ee}\\approx 0$ (1-2 crossing) and $d_{12}\\approx 0$ (2-3 crossing), where ${m}_{ee}$ and $d_{12}$ are respectively the 11-entry and the 12-subdeterminant of the light neutrino mass matrix in the basis where the neutrino Yukawa couplings are diagonal. We show that sufficient lepton asymmetry can be produced only in the 1-2 crossing where $M_1 \\approx M_2 \\approx 10^{8}$ GeV, $M_3 \\approx 10^{14}$ GeV and $(M_2 - M_1)/ M_2 \\lesssim 10^{-5}$.

  2. Neutrino Oscillations. Theory and Experiment

    E-print Network

    Kh. M. Beshtoev

    2002-04-28

    The theoretical schemes on neutrino oscillations are considered. The experimental data on neutrino oscillations from Super-Kamiokande (Japan) and SNO (Kanada) are given. Comparison of these data with theoretical schemes is done. Conclusion is made that the experimental data have confirmed the scheme only with transitions (oscillations) between aromatic $\

  3. Neutrino Theory of Stellar Collapse

    Microsoft Academic Search

    G. Gamow; M. Schoenberg

    1941-01-01

    At the very high temperatures and densities which must exist in the interior of contracting stars during the later stages of their evolution, one must expect a special type of nuclear processes accompanied by the emission of a large number of neutrinos. These neutrinos penetrating almost without difficulty the body of the star, must carry away very large amounts of

  4. Gauge Theory Model of the Neutrino and New Physics Beyond the Standard Model

    E-print Network

    Yue-Liang Wu

    2012-03-05

    Majorana features of neutrinos and SO(3) gauge symmetry of three families enable us to construct a gauge model of neutrino for understanding naturally the observed smallness of neutrino masses and the nearly tri-bimaximal neutrino mixing when combining together with the mechanism of approximate global U(1) family symmetry. The vacuum structure of SO(3) symmetry breaking is found to play an important role. The mixing angle $\\theta_{13}$ and CP-violating phases governed by the vacuum of spontaneous symmetry breaking are in general non-zero and testable experimentally at the allowed sensitivity. The model predicts the existence of vector-like SO(3) triplet charged leptons and vector-like SO(3) triplet Majorana neutrinos as well as SO(3) tri-triplet Higgs bosons, some of them can be light and explored at the colliders LHC and ILC.

  5. Solar neutrinos: experimental review and prospectives

    NASA Astrophysics Data System (ADS)

    Pallavicini, Marco

    2015-04-01

    Solar neutrino physics, after the golden age which led to the discovery of neutrino oscillations, is about to enter the precision era. We summarise here the current experimental knowledge in the field and the future perspectives, showing that solar neutrino detectors are and will remain in the near future a fundamental tool for a deeper understanding of stars, neutrinos, and fundamental physics.

  6. Electromagnetic neutrinos in terrestrial experiments and astrophysics

    E-print Network

    Carlo Giunti; Konstantin A. Kouzakov; Yu-Feng Li; Alexey V. Lokhov; Alexander I. Studenikin; Shun Zhou

    2015-06-17

    An overview of neutrino electromagnetic properties, which open a door to the new physics beyond the Standard Model, is given. The effects of neutrino electromagnetic interactions both in terrestrial experiments and in astrophysical environments are discussed. The experimental bounds on neutrino electromagnetic characteristics are summarized. Future astrophysical probes of electromagnetic neutrinos are outlined.

  7. Neutrinos with Mixing in Twisting Magnetic Fields

    E-print Network

    E. Kh. Akhmedov; S. T. Petcov; A. Yu. Smirnov

    1993-01-06

    Transitions in a system of neutrinos with vacuum mixing and magnetic moments, propagating in matter and transverse magnetic field, are considered. It is shown that in the realistic case of magnetic field direction varying along the neutrino path qualitatively new phenomena become possible: permutation of neutrino conversion resonances, appearance of resonances in the neutrino-antineutrino ($\

  8. Small entries of neutrino mass matrices

    E-print Network

    E. Kh. Akhmedov

    1999-09-15

    We consider phenomenologically allowed structures of the neutrino mass matrix in the case of three light neutrino species. Constraints from the solar, atmospheric and reactor neutrino experiments as well as those from the neutrinoless double beta decay are taken into account. Both hierarchical and quasi-degenerate neutrino mass cases are studied. Assuming maximal $\

  9. Hyperon Production from Neutrino-Nucleon Reaction

    NASA Astrophysics Data System (ADS)

    Wu, Jia-Jun; Zou, Bing-Song

    2015-05-01

    The neutrino induced hyperon production processes may provide a unique clean place for studying low energy interaction and hyperon resonances below KN threshold. The production rates for some neutrino induced hyperon production processes are estimated with theoretical models. Suggestions are made for the study of hyperon production from neutrino-nucleon reaction at present and future neutrino facilities.

  10. Neutrino mass models and CP violation

    SciTech Connect

    Joshipura, Anjan S. [Physical Research Laboratory, Navarangpura, Ahmedabad, 380 009 (India)

    2011-10-06

    Theoretical ideas on the origin of (a) neutrino masses (b) neutrino mass hierarchies and (c) leptonic mixing angles are reviewed. Topics discussed include (1) symmetries of neutrino mass matrix and their origin (2) ways to understand the observed patterns of leptonic mixing angles and (3)unified description of neutrino masses and mixing angles in grand unified theories.

  11. Dirac or inverse seesaw neutrino masses with B – L gauge symmetry and S? flavor symmetry

    DOE PAGESBeta

    Ma, Ernest; Srivastava, Rahul

    2015-02-01

    Many studies have been made on extensions of the standard model with B – L gauge symmetry. The addition of three singlet (right-handed) neutrinos renders it anomaly-free. It has always been assumed that the spontaneous breaking of B – L is accomplished by a singlet scalar field carrying two units of B – L charge. This results in a very natural implementation of the Majorana seesaw mechanism for neutrinos. However, there exists in fact another simple anomaly-free solution which allows Dirac or inverse seesaw neutrino masses. We show for the first time these new possibilities and discuss an application tomore »neutrino mixing with S? flavor symmetry.« less

  12. Enhanced sensitivities for the searches of neutrino magnetic moments through atomic ionization.

    PubMed

    Wong, Henry T; Li, Hau-Bin; Lin, Shin-Ted

    2010-08-01

    A new detection channel on atomic ionization for possible neutrino electromagnetic interactions is identified and studied. Significant sensitivity enhancement is demonstrated when the energy transfer to the target is of the atomic-transition scale. The interaction cross section induced by neutrino magnetic moments (?(?)) is evaluated with the equivalent photon method. A new limit of ?(?)(?[over ¯](e))<1.3×10(-11) ?(B) at 90% confidence level is derived by using current reactor neutrino data. Potential reaches for future experiments are explored. Experiments with sub-keV sensitivities can probe ?(?) to 10(-13) ?(B). Positive observations of ?(?) in this range would imply that neutrinos are Majorana particles. PMID:20867973

  13. Neutrino oscillation results from MINOS

    SciTech Connect

    Sousa, Alexandre; /Oxford U.

    2007-08-01

    The Main Injector Neutrino Oscillation Search (MINOS) long-baseline experiment has been actively collecting beam data since 2005, having already accumulated 3 x 10{sup 20} protons-on-target (POT). MINOS uses the Neutrinos at the Main Injector (NuMI) neutrino beam measured in two locations: at Fermilab, close to beam production, and 735 km downstream, in Northern Minnesota. By observing the oscillatory structure in the neutrino energy spectrum, MINOS can precisely measure the neutrino oscillation parameters in the atmospheric sector. These parameters were determined to be |{Delta}m{sub 32}{sup 2}| = 2.74{sub -0.26}{sup +0.44} x 10{sup -3} eV{sup 2}/c{sup 4} and sin{sup 2}(2{theta}{sub 23}) > 0.87 (68% C.L.) from analysis of the first year of data, corresponding to 1.27 x 10{sup 20} POT.

  14. Oscillations of solar atmosphere neutrinos

    NASA Astrophysics Data System (ADS)

    Fogli, G. L.; Lisi, E.; Mirizzi, A.; Montanino, D.; Serpico, P. D.

    2006-11-01

    The Sun is a source of high-energy neutrinos (E?10GeV) produced by cosmic ray interactions in the solar atmosphere. We study the impact of three-flavor oscillations (in vacuum and in matter) on solar atmosphere neutrinos, and calculate their observable fluxes at Earth, as well as their event rates in a kilometer-scale detector in water or ice. We find that peculiar three-flavor oscillation effects in matter, which can occur in the energy range probed by solar atmosphere neutrinos, are significantly suppressed by averaging over the production region and over the neutrino and antineutrino components. In particular, we find that the relation between the neutrino fluxes at the Sun and at the Earth can be approximately expressed in terms of phase-averaged vacuum oscillations, dominated by a single mixing parameter (the angle ?23).

  15. Voids in massive neutrino cosmologies

    E-print Network

    Massara, Elena; Viel, Matteo; Sutter, P M

    2015-01-01

    Cosmic voids are a promising environment to characterize neutrino-induced effects on the large-scale distribution of matter in the universe. We perform a comprehensive numerical study of the statistical properties of voids, identified both in the matter and galaxy distributions, in massive and massless neutrino cosmologies. The matter density field is obtained by running several independent $N$-body simulations with cold dark matter and neutrino particles, while the galaxy catalogs are modeled by populating the dark matter halos in simulations via a halo occupation distribution (HOD) model to reproduce the clustering properties observed by the Sloan Digital Sky Survey (SDSS) II Data Release 7. We focus on the impact of massive neutrinos on the following void statistical properties: number density, ellipticities, two-point statistics, density and velocity profiles. Considering the matter density field, we find that voids in massive neutrino cosmologies are less evolved than those in the corresponding massless ...

  16. Neutrinos Get Under Your Skin

    SciTech Connect

    Kayser, Boris

    2005-08-30

    The enigmatic neutrinos are among the most abundant of the tiny particles that make up our universe. They are a billion times more abundant than the particles of which the earth and we humans are made. Thus, to understand the universe, we must understand the neutrinos. Moving ghostlike, almost invisibly, through matter, these particles are very hard to pin down and study. However, dramatic progress has recently been made. In this lecture, the neutrinos will be introduced. Their behavior, so different from that of everyday objects, will be explained, and recent discoveries will be described. The open questions about neutrinos, forthcoming attempts to answer these questions, and the role of neutrinos in shaping the universe and making human life possible, will all be explained.

  17. ANTARES deep sea neutrino telescope results

    NASA Astrophysics Data System (ADS)

    Mangano, Salvatore; ANTARES Collaboration

    2014-06-01

    The ANTARES experiment is currently the largest underwater neutrino telescope in the Northern Hemisphere. It is taking high quality data since 2007. Its main scientific goal is to search for high energy neutrinos that are expected from the acceleration of cosmic rays from astrophysical sources. This contribution reviews the status of the detector and presents several analyses carried out on atmospheric muons and neutrinos. For example it shows the results from the measurement of atmospheric muon neutrino spectrum and of atmospheric neutrino oscillation parameters as well as searches for neutrinos from steady cosmic point-like sources, for neutrinos from gamma ray bursts and for relativistic magnetic monopoles.

  18. Flavor distribution of UHE cosmic neutrino oscillations at neutrino telescopes

    NASA Astrophysics Data System (ADS)

    Xing, Zhi-Zhong

    2009-04-01

    If the ultrahigh-energy (UHE) cosmic neutrinos produced from a distant astrophysical source can be measured at a km-size neutrino telescope such as the IceCube or KM3NeT, they will open a new window to understand the nature of flavor mixing and to probe possible new physics. Considering the conventional UHE cosmic neutrino source with the flavor ratio ?e:??:??=1:2:0, I point out two sets of conditions for the flavor democracy ?eT:??T:??T=1:1:1 to show up at neutrino telescopes: either ?13=0 and ?23=?/4 (CP invariance) or ?=±?/2 and ?23=?/4 (CP violation) in the standard parametrization of the 3×3 neutrino mixing matrix V. Allowing for slight ?-? symmetry breaking effects characterized by ??[-0.1,+0.1], I find ?eT:??T:??T=(1-2?):(1+?):(1+?) as a good approximation. Another possibility to constrain ? is to detect the ? flux of E?6.3PeV via the Glashow resonance channel ?e?W?anything. I also give some brief comments on (1) possible non-unitarity of V in the seesaw framework and its effects on the flavor distribution at neutrino telescopes and (2) a generic description and determination of the cosmic neutrino flavor composition at distant astrophysical sources.

  19. Homestake result, sterile neutrinos and low energy solar neutrino experiments

    E-print Network

    De Holanda, P C

    2003-01-01

    The large mixing (LMA) MSW solution predicts ~2-sigma higher Ar-production rate, Q_{Ar}, than the Homestake result. Also there is no apparent upturn of the spectrum (R=N_obs/N_SSM) at low energies in SNO and Super-Kamiokande (SK). Both these facts can be explained if a light, \\Delta m^2_{01} ~ (2 - 20)10^{-5} eV^2, sterile neutrino exists which mixes very weakly with active neutrinos: sin^2 2\\alpha ~ (10^{-5} - 10^{-3}). We perform both the analytical and numerical study of conversion effects in the system of two active neutrinos with the LMA parameters and one weakly mixed sterile neutrino. The presence of sterile neutrino leads to a dip in the survival probability in the intermediate energy range E = (0.5 - 5) MeV thus suppressing the Be, or/and pep, CNO as well as B neutrino fluxes. Apart from diminishing Q_{Ar} it leads also to decrease of the Ge-production rate and may lead to decrease of the BOREXINO signal and CC/NC ratio at SNO. Future studies of the solar neutrinos by SNO, SK, BOREXINO and KamLAND as...

  20. Neutrino electromagnetic properties and magnetic moment induced transition of neutrino between different mass states

    E-print Network

    A. Grigoriev; A. Lokhov; A. Studenikin; A. Ternov

    2010-12-14

    The Spin Light of neutrino, the process that becomes possible in matter for a neutrino with nontrivial electromagnetic properties, is considered for the case of nonequal neutrino masses in the initial and final states.

  1. Theory of neutrino oscillations with entanglement

    NASA Astrophysics Data System (ADS)

    Kayser, Boris; Kopp, Joachim; Robertson, R. G. Hamish; Vogel, Petr

    2010-11-01

    We show that, despite appearances, a theoretical approach to neutrino oscillation in which the neutrino and its interaction partners are entangled yields the standard result for the neutrino oscillation wavelength. We also shed some light on the question of why plane-wave approaches to the neutrino oscillation problem can yield the correct oscillation wavelength even though they do not explicitly account for the localization of the neutrino source and the detector.

  2. Parametric resonance in neutrino oscillations in matter

    E-print Network

    E. Kh. Akhmedov

    1999-07-20

    Neutrino oscillations in matter can exhibit a specific resonance enhancement -- parametric resonance, which is different from the MSW resonance. Oscillations of atmospheric and solar neutrinos inside the earth can undergo parametric enhancement when neutrino trajectories cross the core of the earth. In this paper we review the parametric resonance of neutrino oscillations in matter. In particular, physical interpretation of the effect and the prospects of its experimental observation in oscillations of solar and atmospheric neutrinos in the earth are discussed.

  3. Search for neutrinos from gamma-ray bursts with the Baikal neutrino telescope NT200

    Microsoft Academic Search

    A. V. Avrorin; V. M. Aynutdinov; I. A. Belolaptikov; D. Yu. Bogorodsky; N. M. Budnev; R. Wischnewski; O. N. Gaponenko; K. V. Golubkov; O. A. Gress; T. I. Gress; O. G. Grishin; I. A. Danilchenko; Zh.-A. M. Dzhilkibaev; G. V. Domogatsky; A. A. Doroshenko; A. N. Dyachok; V. A. Zhukov; A. V. Zagorodnikov; A. M. Klabukov; A. I. Klimov; K. V. Konishchev; A. V. Korobchenko; A. P. Koshechkin; L. A. Kuzmichev; V. F. Kulepov; D. A. Kuleshov; V. I. Ljashuk; A. Middell; M. B. Milenin; R. R. Mirgazov; S. P. Mikheev; E. A. Osipova; A. I. Panfilov; L. V. Pan'kov; G. L. Pan'kov; A. A. Perevalov; D. A. Petukhov; E. N. Pliskovsky; V. A. Poleshchuk; E. G. Popova; V. V. Prosin; M. I. Rozanov; V. Yu. Rubzov; E. V. Rjabov; O. V. Suvorova; B. A. Tarashchansky; S. V. Fialkovsky; B. A. Shoibonov; A. A. Sheifler; A. V. Shirokov; Ch. Spiering; A. S. Yagunov

    2011-01-01

    We present the results of our search for neutrino events coinciding in time and direction with gamma-ray bursts (GRBs) with the Baikal underwater neutrino telescope NT200. No events confirming a neutrino accompaniment of GRBs have been detected. Model-independent limits (Greens function) on the neutrino flux from GRBs have been obtained. For the Waxman-Bahcall neutrino spectrum, the limit on the neutrino

  4. Search for Neutrino-less Double Beta Decay with CANDLES

    NASA Astrophysics Data System (ADS)

    Umehara, S.; Kishimoto, T.; Nomachi, M.; Ajimura, S.; Iida, T.; Nakajima, K.; Ichimura, K.; Matsuoka, K.; Saka, M.; Ishikawa, T.; Tanaka, D.; Tanaka, M.; Maeda, T.; Yoshida, S.; Suzuki, K.; Ito, G.; Kakubata, H.; Wang, W.; Trang, V. T. T.; Chan, W. M.; Takemoto, J.; Doihara, M.; Ohata, T.; Tetsuno, K.; Tamagawa, Y.; Ogawa, I.; Ueno, T.; Maeda, S.; Yamamoto, A.; Tomita, S.; Fujita, G.; Kawamura, A.; Harada, T.; Inukai, Y.; Sakamoto, K.; Yoshizawa, M.; Fushimi, K.; Hazama, R.; Nakatani, N.; Ohsumi, H.; Okada, K.

    CANDLES is the project to search for neutrino-less double beta decay (0???) of 48Ca. The observation of 0??? will prove existence of a massive Majorana neutrino. For the 0??? measurement, we need a low background condition because of a low decay rate of 0???. Now we installed the CANDLES III system at the Kamioka underground laboratory. The CANDLES III system realizes the low background condition by a characteristic structure and data analyses for background rejection. Here we report performances of the CANDLES III system.

  5. Hierarchical Majorana Scales in the Seesaw Model

    E-print Network

    Guo-Hong Wu

    2000-04-10

    If the mixing angles in each of the seesaw sectors are all small, and the neutrino masses are hierarchical, we study the conditions for large neutrino mixing using triangular matrices. In particular, the implication of the neutrino oscillation data for the mass hierarchy in the heavy Majorana sector is examined, and the heavy Majorana scales are shown to depend sensitively on the solar mixing angle.

  6. Radiative Corrections to Light Neutrino Masses in Low Scale Type I Seesaw Scenarios and Neutrinoless Double Beta Decay

    E-print Network

    Lopez-Pavon, J; Petcov, S T

    2015-01-01

    We perform a detailed analysis of the one-loop corrections to the light neutrino mass matrix within low scale type I seesaw extensions of the Standard Model and their implications in experimental searches for neutrinoless double beta decay. We show that a sizable contribution to the effective Majorana neutrino mass from the exchange of heavy Majorana neutrinos is always possible, provided one requires a fine-tuned cancellation between the tree-level and one-loop contribution to the light neutrino masses. We quantify the level of fine-tuning as a function of the seesaw parameters and introduce a generalisation of the Casas-Ibarra parametrization of the neutrino Yukawa matrix, which easily allows to include the one-loop corrections to the light neutrino masses.

  7. MUON STORAGE RINGS - NEUTRINO FACTORIES

    SciTech Connect

    PARSA,Z.

    2000-05-30

    The concept of a muon storage ring based Neutrino Source (Neutrino Factory) has sparked considerable interest in the High Energy Physics community. Besides providing a first phase of a muon collider facility, it would generate more intense and well collimated neutrino beams than currently available. The BNL-AGS or some other proton driver would provide an intense proton beam that hits a target, produces pions that decay into muons. The muons must be cooled, accelerated and injected into a storage ring with a long straight section where they decay. The decays occurring in the straight sections of the ring would generate neutrino beams that could be directed to detectors located thousands of kilometers away, allowing studies of neutrino oscillations with precisions not currently accessible. For example, with the neutrino source at BNL, detectors at Soudan, Minnesota (1,715 km), and Gran Sasso, Italy (6,527 km) become very interesting possibilities. The feasibility of constructing and operating such a muon-storage-ring based Neutrino-Factory, including geotechnical questions related to building non-planar storage rings (e.g. at 8{degree} angle for BNL-Soudan, and 3{degree} angle for BNL-Gran Sasso) along with the design of the muon capture, cooling, acceleration, and storage ring for such a facility is being explored by the growing Neutrino Factory and Muon Collider Collaboration (NFMCC). The authors present overview of Neutrino Factory concept based on a muon storage ring, its components, physics opportunities, possible upgrade to a full muon collider, latest simulations of front-end, and a new bowtie-muon storage ring design.

  8. Analyzing Atmospheric Neutrino Oscillations

    SciTech Connect

    Escamilla, J.; Ernst, D. J. [Department of Physics and Astronomy Vanderbilt University Nashville, TN, 37235 (United States); Latimer, D. C. [Department of Physics and Astronomy University of Kentucky, Lexington, KY, 40506 (United States)

    2007-10-26

    We provide a pedagogic derivation of the formula needed to analyze atmospheric data and then derive, for the subset of the data that are fully-contained events, an analysis tool that is quantitative and numerically efficient. Results for the full set of neutrino oscillation data are then presented. We find the following preliminary results: 1.) the sub-dominant approximation provides reasonable values for the best fit parameters for {delta}{sub 32}, {theta}{sub 23}, and {theta}{sub 13} but does not quantitatively provide the errors for these three parameters; 2.) the size of the MSW effect is suppressed in the sub-dominant approximation; 3.) the MSW effect reduces somewhat the extracted error for {delta}{sub 32}, more so for {theta}{sub 23} and {theta}{sub 13}; 4.) atmospheric data alone constrains the allowed values of {theta}{sub 13} only in the sub-dominant approximation, the full three neutrino calculations requires CHOOZ to get a clean constraint; 5.) the linear in {theta}{sub 13} terms are not negligible; and 6.) the minimum value of {theta}{sub 13} is found to be negative, but at a statistically insignificant level.

  9. Supernova neutrinos and nucleosynthesis

    E-print Network

    Martínez-Pinedo, G; Huther, L

    2013-01-01

    Observations of metal-poor stars indicate that at least two different nucleosynthesis sites contribute to the production of r-process elements. One site is responsible for the production of light r-process elements Z<~50 while the other produces the heavy r-process elements. We have analyzed recent observations of metal-poor stars selecting only stars that are enriched in light r-process elements and poor in heavy r-process elements. We find a strong correlation between the observed abundances of the N=50 elements (Sr, Y and Zr) and Fe. It suggest that neutrino-driven winds from core-collapse supernova are the main site for the production of these elements. We explore this possibility by performing nucleosynthesis calculations based on long term Boltzmann neutrino transport simulations. They are based on an Equation of State that reproduces recent constrains on the nuclear symmetry energy. We predict that the early ejecta is neutron-rich with Ye ~ 0.48, it becomes proton rich around 4 s and reaches Ye = 0....

  10. Solar monopoles and terrestrial neutrinos

    SciTech Connect

    Frieman, J.

    1988-04-01

    Magnetic monopoles captured in the core of the sun may give rise to a substantial flux of energetic neutrinos by catalyzing the decay of solar hydrogen. We discuss the expected neutrino flux in underground detectors under different assumptions about solar interior conditions. Although a monopole flux as low as F/sub M/ /approximately/ 10/sup /minus/24/ cm/sup /minus/2/ sec/sup /minus/1/ sr/sup /minus/1/ could give rise to a neutrino flux above atmospheric background, due to M/bar M/ annihilation, this does not translate into a reliable monopole flux bound stronger than the Parker limit. 8 refs., 1 fig.

  11. Neutrino Physics with Thermal Detectors

    SciTech Connect

    Nucciotti, A. [Dipartimento di Fisica, Universita di Milano Bicocca and INFN Sezione di Milano-Bicocca Piazza della Scienza, 3, 20126 Milano (Italy)

    2009-11-09

    The investigation of fundamental neutrino properties like its mass and its nature calls for the design of a new generation of experiments. High sensitivity, high energy resolution, and versatility together with the possibility of a simple multiplexing scheme are the key features of future detectors for these experiments. Thermal detectors can combine all these features. This paper reviews the status and the perspectives for what concerns the application of this type of detectors to neutrino physics, focusing on direct neutrino mass measurements and neutrinoless double beta decay searches.

  12. Bruno Pontecorvo and the neutrino

    NASA Astrophysics Data System (ADS)

    Bilenky, S. M.

    2014-05-01

    This paper commemorates the 100th anniversary of the birth of the great scientist and neutrino researcher Bruno Pontecorvo. His major contributions are reviewed, including the radiochemical method of neutrino detection, the idea of the ?-{ e} universality of the weak interaction, and the proposal of an accelerator experiment to prove that ? e and ?_? are different particles. Pontecorvo's fundamental idea of neutrino masses, mixing, and oscillations is discussed in detail, as is the development of this idea by Pontecorvo and Gribov and Pontecorvo and the author.

  13. Superluminal neutrinos and domain walls

    E-print Network

    Peng Wang; Houwen Wu; Haitang Yang

    2011-10-08

    In this letter, we propose that the recent measurement of superluminal neutrinos in OPERA could be explained by the existence of a domain wall which is left behind after the phase transition of some scalar field in the universe. The scalar field couples to the neutrino and photon field with different effective couplings. It causes different effective metrics and the emergence of superluminal neutrinos. Moreover, if the supernova and the earth are in the same plane parallel to the wall, or the thickness of the wall is much smaller than the distance from the supernova to the earth, the contradiction between OPERA and SN1987a can be reconciled.

  14. Neutrino masses and mixing with seesaw mechanism and universal breaking of extended democracy

    E-print Network

    E. Kh. Akhmedov; G. C. Branco; F. R. Joaquim; J. I. Silva-Marcos

    2000-10-18

    In the framework of a minimal extension of the SM, where the only additional fields are three right-handed neutrinos, we suggest that the charged lepton, the Dirac neutrino and the right-handed Majorana neutrino mass matrices are all, to leading approximation, proportional to the democratic matrix. With the further assumption that the breaking of this extended democracy is universal for all leptonic mass matrices, a large mixing in the 2-3 sector can be obtained and is linked to the seesaw mechanism, together with the existence of a strong hierarchy in the masses of right-handed neutrinos. The structure of the resulting effective mass matrix of light neutrinos is stable against the RGE evolution, and a good fit to all solar and atmospheric neutrino data is obtained.

  15. MOON for a next-generation neutrino-less double-beta decay experiment: Present status and perspective

    SciTech Connect

    Shima, T.; /Osaka U., Res. Ctr. Nucl. Phys.; Doe, P.J.; /Washington U., Seattle; Ejiri, H.; /Osaka U., Res. Ctr. Nucl. Phys. /NIRS, Chiba /Prague, Tech. U.; Elliot, S.R.; /Washington U., Seattle /Los Alamos; Engel, J.; /North Carolina U.; Finger, M.; /Charles U.; Finger, M.; /Charles U.; Fushimi, K.; /Tokushima U.; Gehman, V.M.; /Washington U., Seattle /Los Alamos; Greenfield, M.B.; /Tokyo, Intl. Christian U.; Hazama, R.; /Hiroshima U. /NIRS, Chiba

    2008-01-01

    The performance of the MOON detector for a next-generation neutrino-less double-beta decay experiment was evaluated by means of the Monte Carlo method. The MOON detector was found to be a feasible solution for the future experiment to search for the Majorana neutrino mass in the range of 100-30 meV.

  16. The SNO-Experiment and Neutrino Oscillations

    NASA Astrophysics Data System (ADS)

    Faessler, Amand

    2002-01-01

    Using the pre-SNO neutrino oscillation data of the solar and the atmospheric neutrino oscillations including and excluding the LSND (Los Alamos) measurements fits for the three mixing angle of the unitary transformation between the three neutrino mass eigenstates and the weak eigenstates are given. At the same time the differences of the squared masses are fitted to the data. Using an averaged upper value of delimiter "426830A m? e > = 0.62 eV from the neutrino double beta decay, one can limit the sum of the three neutrino masses to be less than 2.53 eV. The new data from the Sudbury Neutrino Observatory allow for the first time with the help of the SuperKamiokande data to determine the solar e and (? + ? ) neutrino fluxes separately. The sum is within errors identical to the theoretical electron neutrino flux from the sun. We thus see all expected solar neutrinos. They only oscillated partially from electron to ? + ? neutrinos. In the last part we report calculations of neutrino masses in the R-parity violating Minimal Supersymmetric Standard Model (R/ MSSM). The R-parity violating interaction mixes the three neutrino flavors by R-parity violation with the four neutralinos (photino, zino and the two higgsinos). One finds neutrino masses for the first two neutrinos between 0.001 and 0.04 eV and for the third one between 0.03 and 1 eV.

  17. First measurement of the flux of solar neutrinos from the sun at the Sudbury Neutrino Observatory

    NASA Astrophysics Data System (ADS)

    Wittich, Peter

    2000-12-01

    The Sudbury Neutrino Observatory (SNO) is a second generation solar neutrino detector. SNO is the first experiment that is able to measure both the electron neutrino flux and a flavor-blind flux of all active neutrino types, allowing a model-independent determination if the deficit of solar neutrinos known as the solar neutrino problem is due to neutrino oscillation. The Sudbury Neutrino Observatory started taking production data in November, 1999. A measurement of the charged current rate will be the first indication if SNO too sees a suppression of the solar neutrino signal relative to the theoretical predictions. Such a confirmation is the first step in SNO's ambitious science program. In this thesis, we present evidence that SNO is seeing solar neutrinos and a preliminary ratio of the measured vs predicted rate of electrons as induced by 8B neutrinos in the ?e, + d --> p + p + e charged-current (CC) reaction.

  18. Neutrino propagation in nuclear medium and neutrinoless double-? decay.

    PubMed

    Kovalenko, S; Krivoruchenko, M I; Simkovic, F

    2014-04-11

    We discuss a novel effect in neutrinoless double-? (0???) decay related with the fact that its underlying mechanisms take place in the nuclear matter environment. We study the neutrino exchange mechanism and demonstrate the possible impact of nuclear medium via lepton-number-violating (LNV) four-fermion interactions of neutrinos with quarks from a decaying nucleus. The net effect of these interactions is the generation of an effective in-medium Majorana neutrino mass matrix. The enhanced rate of the 0??? decay can lead to the apparent incompatibility of observations of the 0??? decay with the value of the neutrino mass determined or restricted by the ?-decay and cosmological data. The effective neutrino masses and mixing are calculated for the complete set of the relevant four-fermion neutrino-quark operators. Using experimental data on the 0??? decay in combination with the ?-decay and cosmological data, we evaluate the characteristic scales of these operators: ?LNV?2.4??TeV. PMID:24765948

  19. Neutrino Decays and Neutrino Electron Elastic Scattering in Unparticle Physics

    E-print Network

    Shun Zhou

    2007-10-30

    Following Georgi's unparticle scheme, we examine the effective couplings between neutrinos and unparticle operators. As an immediate consequence, neutrinos become unstable and can decay into the unparticle stuff. Assuming the dimension transmutation scale is around $\\Lambda^{}_{\\cal U} \\sim 1 ~{\\rm TeV}$, we implement the cosmological limit on the neutrino lifetime to constrain the neutrino-unparticle couplings for different scaling dimensions $d$. In addition, provided that the electron-unparticle coupling is restricted due to the precise measurement of the anomalous magnetic moment of electron, we calculate the unparticle contribution to the neutrino-electron elastic scattering. It is more important to jointly deal with the couplings of the unparticle to the standard model particles rather than separately. Taking into account both electron- and neutrino-unparticle couplings, we find that the scaling dimension of the scalar unparticle should lie in the narrow range $1 < d < 2$ by requiring the observables to be physically meaningful. However, there is no consistent range of $d$ for the vector unparticle operator.

  20. Neutrino mass and mixing, and non-accelerator experiments

    SciTech Connect

    Robertson, R.G.H.

    1992-01-01

    We review the current status of experimental knowledge about neutrinos derived from kinematic mass measurements, neutrino oscillation searches at reactors and accelerators, solar neutrinos, atmospheric neutrinos, and single and double beta decay. The solar neutrino results yield fairly strong and consistent indication that neutrino oscillations are occurring. Other evidence for new physics is less consistent and convincing.

  1. Neutrino mass and mixing, and non-accelerator experiments

    SciTech Connect

    Robertson, R.G.H.

    1992-10-01

    We review the current status of experimental knowledge about neutrinos derived from kinematic mass measurements, neutrino oscillation searches at reactors and accelerators, solar neutrinos, atmospheric neutrinos, and single and double beta decay. The solar neutrino results yield fairly strong and consistent indication that neutrino oscillations are occurring. Other evidence for new physics is less consistent and convincing.

  2. Neutrinos and Cosmology: an update

    E-print Network

    Ofelia Pisanti; P. D. Serpico

    2005-07-14

    We review the current cosmological status of neutrinos, with particular emphasis on their effects on Big Bang Nucleosynthesis, Large Scale Structure of the universe and Cosmic Microwave Background Radiation measurements.

  3. Unparticle effects in neutrino telescopes

    SciTech Connect

    Gonzalez-Sprinberg, G.; Martinez, R.; Sampayo, Oscar A. [Instituto de Fisica, Facultad de Ciencias, Universidad de la Republica, Igua 4225, 11400 Montevideo (Uruguay); Departamento de Fisica, Universidad Nacional, Bogota (Colombia); Departamento de Fisica, Universidad Nacional de Mar del Plata, Funes 3350, (7600) Mar del Plata (Argentina)

    2009-03-01

    Recently H. Georgi has introduced the concept of unparticles in order to describe the low energy physics of a nontrivial scale invariant sector of an effective theory. We investigate its physical effects on the neutrino flux to be detected in a kilometer cubic neutrino telescope such as IceCube. We study the effects, on different observables, of the survival neutrino flux after through the Earth, and the regeneration originated in the neutral currents. We calculate the contribution of unparticle physics to the neutrino-nucleon interaction and, then, to the observables in order to evaluate detectable effects in IceCUbe. Our results are compared with the bounds obtained by other nonunderground experiments. Finally, the results are presented as an exclusion plot in the relevant parameters of the new physics stuff.

  4. The Evolution of Neutrino Astronomy

    E-print Network

    John Bahcall; Raymond Davis, Jr

    2000-04-08

    How did neutrino astronomy evolve? Are there any useful lessons for astronomers and physicists embarking on new observational ventures today? We answer the first question; the reader can can decide if there are any useful parallels for other fields.

  5. High-Energy Neutrino Astronomy

    E-print Network

    F. Halzen

    2004-02-03

    Kilometer-scale neutrino detectors such as IceCube are discovery instruments covering nuclear and particle physics, cosmology and astronomy. Examples of their multidisciplinary missions include the search for the particle nature of dark matter and for additional small dimensions of space. In the end, their conceptual design is very much anchored to the observational fact that Nature accelerates protons and photons to energies in excess of $10^{20}$ and $10^{13}$ eV, respectively. The cosmic ray connection sets the scale of cosmic neutrino fluxes. In this context, we discuss the first results of the completed AMANDA detector and the reach of its extension, IceCube. Similar experiments are under construction in the Mediterranean. Neutrino astronomy is also expanding in new directions with efforts to detect air showers, acoustic and radio signals initiated by super-EeV neutrinos.

  6. High-Energy Neutrino Astronomy

    E-print Network

    F. Halzen

    2005-01-26

    Kilometer-scale neutrino detectors such as IceCube are discovery instruments covering nuclear and particle physics, cosmology and astronomy. Examples of their multidisciplinary missions include the search for the particle nature of dark matter and for additional small dimensions of space. In the end, their conceptual design is very much anchored to the observational fact that Nature accelerates protons and photons to energies in excess of 10^{20} and 10^{13} eV, respectively. The cosmic ray connection sets the scale of cosmic neutrino fluxes. In this context, we discuss the first results of the completed AMANDA detector and the reach of its extension, IceCube. Similar experiments are under construction in the Mediterranean. Neutrino astronomy is also expanding in new directions with efforts to detect air showers, acoustic and radio signals initiated by neutrinos with energies similar to those of the highest energy cosmic rays.

  7. On the muon neutrino mass

    E-print Network

    N. Angelov; F. Balestra; Yu. Batusov; A. Bianconi; M. P. Bussa; L. Busso; L. Ferrero; R. Garfagnini; I. Gnesi; E. Lodi Rizzini; A. Maggiora; D. Panzieri; G. Piragino; G. Pontecorvo; F. Tosello; L. Venturelli

    2006-05-03

    During the runs of the PS 179 experiment at LEAR of CERN, we photographed an event of antiproton-Ne absorption, with a complete pi+ -> mu+ ->e+ chain. From the vertex of the reaction a very slow energy pi+ was emitted. The pi+ decays into a mu+ and subsequently the mu+ decays into a positron. At the first decay vertex a muon neutrino was emitted and at the second decay vertex an electron neutrino and a muon antineutrino. Measuring the pion and muon tracks and applying the momentum and energy conservation and using a classical statistical interval estimator, we obtained an experimental upper limit for the muon neutrino mass: m_nu < 2.2 MeV at a 90% confidence level. A statistical analysis has been performed of the factors contributing to the square value of the neutrino mass limit.

  8. Solar Neutrino Experiments: New Physics?

    E-print Network

    John N. Bahcall

    1993-07-07

    Physics beyond the simplest version of the standard electroweak model is required to reconcile the results of the chlorine and the Kamiokande solar neutrino experiments. None of the 1000 solar models in a full Monte Carlo simulation is consistent with the results of the chlorine or the Kamiokande experiments. Even if the solar models are forced articficially to have a ${}^8 B$ neutrino flux in agreement with the Kamiokande experiment, none of the fudged models agrees with the chlorine observations. This comparison shows that consistency of the chlorine and Kamiokande experiments requires some physical process that changes the shape of the ${}^8 B$ neutrino energy spectrum. The GALLEX and SAGE experiments, which currently have large statistical uncertainties, differ from the predictions of the standard solar model by $2 \\sigma$ and $3 \\sigma$, respectively. The possibility that the neutrino experiments are incorrect is briefly discussed.

  9. Research in Neutrino Physics

    SciTech Connect

    Busenitz, Jerome [The University of Alabama

    2014-09-30

    Research in Neutrino Physics We describe here the recent activities of our two groups over the first year of this award (effectively November 2010 through January 2012) and our proposed activities and associated budgets for the coming grant year. Both of our groups are collaborating on the Double Chooz reactor neutrino experiment and are playing major roles in calibration and analysis. A major milestone was reached recently: the collaboration obtained the first result on the search for 13 based on 100 days of data from the far detector. Our data indicates that 13 is not zero; specifically the best fit of the neutrino oscillation hypothesis to our data gives sin2 (2 13) = 0.086 ± 0.041 (stat) ± 0.030 (syst) The null oscillation hypothesis is excluded at the 94.6% C.L. This result1 has been submitted to Physical Review Letters. As we continue to take data with the far detector in the coming year, in parallel with completing the construction of the near lab and installing the near detector, we expect the precision of our measurement to improve as we gather significantly more statistics, gain better control of backgrounds through use of partial power data and improved event selection, and better understand the detector energy scale and detection efficiency from calibration data. With both detectors taking data starting in the second half of 2013, we expect to further drive down the uncertainty on our measurement of sin2 (2 13) to less than 0.02. Stancu’s group is also collaborating on the MiniBooNE experiment. Data taking is scheduled to continue through April, by which time 1.18 × 1021 POT is projected. The UA group is playing a leading role in the measurement of antineutrino cross sections, which should be the subject of a publication later this year as well as of Ranjan Dharmapalan’s Ph.D. thesis, which he is expected to defend by the end of this year. It is time to begin working on projects which will eventually succeed Double Chooz and MiniBooNE as the main foci of our efforts. The Stancu group plans to become re–involved in LBNE and possibly also to join NO A, and the Busenitz group has begun to explore joining a direct dark matter search.

  10. The majorana 76Ge double-beta decay project

    Microsoft Academic Search

    C. E. Aalseth; E. Adles; D. Anderson; F. T. Avignone; A. Barabash; T. W. Bowyer; R. L. Brodzinski; V. Brudanin; A. Champangne; J. I. Collar; P. J. Doe; S. Egorov; S. R. Elliott; H. A. Farach; R. Gaitskell; D. Jordan; R. K. Jain; K. Kazkaz; G. King; O. Kochetov; S. Konovalov; R. Kouzes; H. S. Miley; J. M. Palms; W. K. Pitts; J. H. Reeves; R. G. H. Robertson; R. Rohm; S. Sandukovsky; L. E. Smith; V. Stekhanov; R. C. Thompson; W. Tornow; V. Umatov; R. Warner; J. Webb; J. F. Wilkerson; A. Young

    2003-01-01

    The interest and relevance of next-generation 0v ??-decay experiments is increasing. Even with nonzero neutrino mass strongly suggested by solar and atmospheric neutrino experiments sensitive to ?m2, 0v ??-decay experiments are still the only way to establish the Dirac or Majorana nature of neutrinos by measuring the effective electron neutrino mass, ?mv?. In addition, the atmospheric neutrino oscillation experiments imply

  11. Theory of neutrinos: a white paper

    NASA Astrophysics Data System (ADS)

    Mohapatra, R. N.; Antusch, S.; Babu, K. S.; Barenboim, G.; Chen, M.-C.; de Gouvêa, A.; de Holanda, P.; Dutta, B.; Grossman, Y.; Joshipura, A.; Kayser, B.; Kersten, J.; Keum, Y. Y.; King, S. F.; Langacker, P.; Lindner, M.; Loinaz, W.; Masina, I.; Mocioiu, I.; Mohanty, S.; Murayama, H.; Pascoli, S.; Petcov, S. T.; Pilaftsis, A.; Ramond, P.; Ratz, M.; Rodejohann, W.; Shrock, R.; Takeuchi, T.; Underwood, T.; Wolfenstein, L.

    2007-11-01

    This paper is a review of the present status of neutrino mass physics, which grew out of an APS sponsored study of neutrinos in 2004. After a discussion of the present knowledge of neutrino masses and mixing and some popular ways to probe the new physics implied by recent data, it summarizes what can be learned about neutrino interactions as well as the nature of new physics beyond the Standard Model from the various proposed neutrino experiments. The intriguing possibility that neutrino mass physics may be at the heart of our understanding of a long standing puzzle of cosmology, i.e. the origin of matter-antimatter asymmetry is also discussed.

  12. Solar mass-varying neutrino oscillations

    E-print Network

    V. Barger; Patrick Huber; Danny Marfatia

    2005-09-30

    We propose that the solar neutrino deficit may be due to oscillations of mass-varying neutrinos (MaVaNs). This scenario elucidates solar neutrino data beautifully while remaining comfortably compatible with atmospheric neutrino and K2K data and with reactor antineutrino data at short and long baselines (from CHOOZ and KamLAND). We find that the survival probability of solar MaVaNs is independent of how the suppression of neutrino mass caused by the acceleron-matter couplings varies with density. Measurements of MeV and lower energy solar neutrinos will provide a rigorous test of the idea.

  13. Solar mass-varying neutrino oscillations.

    PubMed

    Barger, V; Huber, Patrick; Marfatia, Danny

    2005-11-18

    We propose that the solar neutrino deficit may be due to oscillations of mass-varying neutrinos (MaVaNs). This scenario elucidates solar neutrino data beautifully while remaining comfortably compatible with atmospheric neutrino and K2K data and with reactor antineutrino data at short and long baselines (from CHOOZ and KamLAND). We find that the survival probability of solar MaVaNs is independent of how the suppression of neutrino mass caused by the acceleron-matter couplings varies with density. Measurements of MeV and lower energy solar neutrinos will provide a rigorous test of the idea. PMID:16384133

  14. Solar Mass-Varying Neutrino Oscillations

    SciTech Connect

    Barger, V.; Huber, Patrick [Department of Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States); Marfatia, Danny [Department of Physics and Astronomy, University of Kansas, Lawrence, Kansas 66045 (United States)

    2005-11-18

    We propose that the solar neutrino deficit may be due to oscillations of mass-varying neutrinos (MaVaNs). This scenario elucidates solar neutrino data beautifully while remaining comfortably compatible with atmospheric neutrino and K2K data and with reactor antineutrino data at short and long baselines (from CHOOZ and KamLAND). We find that the survival probability of solar MaVaNs is independent of how the suppression of neutrino mass caused by the acceleron-matter couplings varies with density. Measurements of MeV and lower energy solar neutrinos will provide a rigorous test of the idea.

  15. Dark matter origins of neutrino masses

    NASA Astrophysics Data System (ADS)

    Huang, Wei-Chih; Deppisch, Frank F.

    2015-05-01

    We propose a simple scenario that directly connects the dark matter (DM) and neutrino mass scales. Based on an interaction between the DM particle ? and the neutrino ? of the form ? ? ? ? /?2, the DM annihilation cross section into the neutrino is determined and a neutrino mass is radiatively induced. Using the observed neutrino mass scale and the DM relic density, the DM mass and the effective scale ? are found to be of the order MeV and GeV, respectively. We construct an ultraviolet-complete toy model based on the inverse seesaw mechanism which realizes this potential connection between DM and neutrino physics.

  16. Future Facilities for Neutrino Oscillation Experiments

    NASA Astrophysics Data System (ADS)

    Goodman, Maury

    1999-10-01

    Atmospheric Neutrino experiments present a fairly compelling case that the phenomenon of neutrino oscillations exist. Long-Baseline experiments at accelerators in Japan, the US and Europe hope to verify the neutrino oscillation interpretation in the next 5 years. Future experiments at muon storage rings and muon colliders are already on the drawing board. The extent of the richness of the neutrino sector has yet to be determined, but a growing interest in neutrinos in the last 5 years has led to a large growth in the number and diversity of neutrino oscillation experiments. The speaker will review some of the major existing and planned experiments which make up this new industry.

  17. Neutrino scattering and flavor transformation in supernovae.

    PubMed

    Cherry, John F; Carlson, J; Friedland, Alexander; Fuller, George M; Vlasenko, Alexey

    2012-06-29

    We argue that the small fraction of neutrinos that undergo direction-changing scattering outside of the neutrinosphere could have significant influence on neutrino flavor transformation in core-collapse supernova environments. We show that the standard treatment for collective neutrino flavor transformation is adequate at late times but could be inadequate in early epochs of core-collapse supernovae, where the potentials that govern neutrino flavor evolution are affected by the scattered neutrinos. Taking account of this effect, and the way it couples to entropy and composition, will require a new approach in neutrino flavor transformation modeling. PMID:23004955

  18. Structure Formation with Decaying Neutrinos

    E-print Network

    M. White; G. Gelmini; J. Silk

    1994-11-23

    We consider the effects of a massive, unstable neutrino on the evolution of large--scale structure and anisotropies in the cosmic microwave background. Comparison with large--scale structure data allows us to rule out a wide range of masses and lifetimes for such neutrinos. We also define a range of masses and lifetimes which delay matter--radiation equality and improve the agreement with the data of Cold Dark Matter models with critical density.

  19. 40 years of neutrino physics

    NASA Astrophysics Data System (ADS)

    Reines, Frederick

    Wolfgang Pauli and Enrico Fermi pioneered the hypothesis and characteristics of the weak interaction and the elementary particle called the neutrino. Since its discovery some forty years ago the neutrino has been shown to be a fundamental constituent of matter with a surprisingly rich, and in very many ways unexpected, set of characteristics ranging from basic roles in the generation of energy in the sun to supernovæ.

  20. Neutrinos And Big Bang Nucleosynthesis

    E-print Network

    Gary Steigman

    2012-07-31

    According to the standard models of particle physics and cosmology, there should be a background of cosmic neutrinos in the present Universe, similar to the cosmic microwave photon background. The weakness of the weak interactions renders this neutrino background undetectable with current technology. The cosmic neutrino background can, however, be probed indirectly through its cosmological effects on big bang nucleosynthesis (BBN) and the cosmic microwave background (CMB) radiation. In this BBN review, focused on neutrinos and, more generally on dark radiation, the BBN constraints on the number of "equivalent neutrinos" (dark radiation), on the baryon asymmetry (baryon density), and on a possible lepton asymmetry (neutrino degeneracy) are reviewed and updated. The BBN constraints on dark radiation and on the baryon density following from considerations of the primordial abundances of deuterium and helium-4 are in excellent agreement with the complementary results from the CMB, providing a suggestive, but currently inconclusive, hint of the presence of dark radiation and, they constrain any lepton asymmetry. For all the cases considered here there is a "lithium problem": the BBN-predicted lithium abundance exceeds the observationally inferred primordial value by a factor of ~3.

  1. Baryon asymmetry from leptogenesis with four zero neutrino Yukawa textures

    SciTech Connect

    Adhikary, Biswajit; Ghosal, Ambar; Roy, Probir, E-mail: biswajit.adhikary@saha.ac.in, E-mail: ambar.ghosal@saha.ac.in, E-mail: probir.roy@saha.ac.in [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India)

    2011-01-01

    The generation of the right amount of baryon asymmetry ? of the Universe from supersymmetric leptogenesis is studied within the type-I seesaw framework with three heavy singlet Majorana neutrinos N{sub i} (i = 1,2,3) and their superpartners. We assume the occurrence of four zeroes in the neutrino Yukawa coupling matrix Y{sub ?}, taken to be ?? symmetric, in the weak basis where N{sub i} (with real masses M{sub i} > 0) and the charged leptons l{sub ?} (? = e,?,?) are mass diagonal. The quadrant of the single nontrivial phase, allowed in the corresponding light neutrino mass matrix m{sub ?}, gets fixed and additional constraints ensue from the requirement of matching ? with its observed value. Special attention is paid to flavor effects in the washout of the lepton asymmetry. We also comment on the role of small departures from high scale ?? symmetry due to RG evolution.

  2. Atmospheric Neutrinos in the MINOS Far Detector

    SciTech Connect

    Howcroft, Caius L.F.

    2004-12-01

    The phenomenon of flavour oscillations of neutrinos created in the atmosphere was first reported by the Super-Kamiokande collaboration in 1998 and since then has been confirmed by Soudan 2 and MACRO. The MINOS Far Detector is the first magnetized neutrino detector able to study atmospheric neutrino oscillations. Although it was designed to detect neutrinos from the NuMI beam, it provides a unique opportunity to measure the oscillation parameters for neutrinos and anti-neutrinos independently. The MINOS Far Detector was completed in August 2003 and since then has collected 2.52 kton-years of atmospheric data. Atmospheric neutrino interactions contained within the volume of the detector are separated from the dominant background from cosmic ray muons. Thirty seven events are selected with an estimated background contamination of less than 10%. Using the detector's magnetic field, 17 neutrino events and 6 anti-neutrino events are identified, 14 events have ambiguous charge. The neutrino oscillation parameters for {nu}{sub {mu}} and {bar {nu}}{sub {mu}} are studied using a maximum likelihood analysis. The measurement does not place constraining limits on the neutrino oscillation parameters due to the limited statistics of the data set analysed. However, this thesis represents the first observation of charge separated atmospheric neutrino interactions. It also details the techniques developed to perform atmospheric neutrino analyses in the MINOS Far Detector.

  3. A search for neutrino oscillations using the CHOOZ 1 km baseline reactor neutrino experiment

    Microsoft Academic Search

    Jean George

    1999-01-01

    Neutrino oscillation searches are an active field of research due to the implications their discovery may have for the solar neutrino anomaly as well as for the atmospheric neutrino anomaly. Their discovery may also have broad ramifications for the Standard Model of Particle Physics as a whole. Results from an oscillation search using the CHOOZ long baseline reactor neutrino experiment

  4. Some Unsettled Questions in the Problem of Neutrino Oscillations. Mechanisms of Neutrino Oscillations

    Microsoft Academic Search

    Khamidbi Muchamedovich Beshtoev

    2003-01-01

    In the modern theory of neutrino oscillations constructed in the framework of the theory particle physics there appears three types of neutrino transitions (oscillations). Then, in order to solve the question of which type of neutrino transitions (oscillations) are realized in nature, in experiments, it is necessary to study profile of neutrino transitions in dependence on distances for determination lengths

  5. Study of Two-Loop Neutrino Mass Generation Models

    E-print Network

    Geng, Chao-Qiang

    2015-01-01

    We study the models with the Majorana neutrino masses generated radiatively by two-loop diagrams due to the Yukawa $\\rho \\bar \\ell_R^c \\ell_R$ and effective $\\rho^{\\pm\\pm} W^\\mp W^\\mp$ couplings along with a scalar triplet $\\Delta$, where $\\rho$ is a doubly charged singlet scalar, $\\ell_R$ the charged lepton and $W$ the charged gauge boson. A generic feature in these types of models is that the neutrino mass spectrum has to be a normal hierarchy. Furthermore, by using the neutrino oscillation data and comparing with the global fitting result in the literature, we find a unique neutrino mass matrix and predict the Dirac and two Majorana CP phases to be $1.40\\pi$, $1.11\\pi$ and $1.47\\pi$, respectively. We also discuss the model parameters constrained by the lepton flavor violating processes and electroweak oblique parameters. In addition, we show that the rate of the neutrinoless double beta decay $(0\

  6. Neutrino masses in the economical 3-3-1 model

    SciTech Connect

    Dong, P. V.; Long, H. N.; Soa, D. V. [Department of Physics and NCTS, National Tsing Hua University, Hsinchu, Taiwan (China); Department of Physics, Kobe University, Nada, Kobe 657-8501 (Japan); Department of Physics, Hanoi University of Education, Hanoi (Viet Nam)

    2007-04-01

    We show that in the framework of the economical 3-3-1 model, the suitable pattern of neutrino masses arises from three quite different sources - the lepton-number conserving, the spontaneous lepton-number breaking, and the explicit lepton-number violating, widely ranging over mass scales including the GUT one: u{approx}O(1) GeV, v{approx_equal}246 GeV, {omega}{approx}O(1) TeV, and M{approx}O(10{sup 16}) GeV. At the tree level, the model contains three Dirac neutrinos: one massless, and two large with degenerate masses in the range of the electron mass. At the one-loop level, the left-handed and right-handed neutrinos obtain Majorana masses M{sub L,R} in orders of 10{sup -2}-10{sup -3} eV and degenerate in M{sub R}=-M{sub L}, while the Dirac masses get a large reduction down to eV scale through a finite mass renormalization. In this model, the contributions of new physics are strongly signified, the degenerations in the masses and the last hierarchy between the Majorana and Dirac masses can be completely removed by heavy particles. All the neutrinos get mass and can fit the data. The acceptable set of the input data does not induce the large lepton flavor violating branching ratios such as Br({mu}{yields}e{gamma})

  7. Oscillation of heavy sterile neutrino in decay of $B \\to \\mu e \\pi$

    E-print Network

    Cvetic, Gorazd; Kogerler, Reinhart; Zamora-Saa, Jilberto

    2015-01-01

    In a scenario with two almost mass degenerate heavy sterile Majorana neutrinos with a mass $\\sim 1$ GeV, we present the semileptonic decay widths of heavy charged pseudoscalars such as $B$ mesons, either lepton-number-violating (LNV: $B^{\\pm} \\to \\mu^{\\pm} e^{\\pm} \\pi^{\\mp}$), or lepton-number-conserving (LNC: $B^{\\pm} \\to \\mu^{\\pm} e^{\\mp} \\pi^{\\pm}$), mediated by such on-shell neutrinos. It had been explained in the literature that such decays may be eventually detected, and that they can present even detectable CP violation effects. In this work we point out that, in addition, such decays may present detectable effects of heavy neutrino oscillation, allowing us to extract the oscillation length and thus the heavy neutrino mass difference $\\Delta M_N$, as well as a CP-violating Majorana phase.

  8. One Right-handed Neutrino to Generate Complete Neutrino Mass Spectrum in the Framework of NMSSM

    E-print Network

    Yi-Lei Tang

    2014-11-28

    The see-saw mechanism is usually applied to explain the lightness of neutrinos. The traditional see-saw mechanism introduces at least two right-handed neutrinos for the realistic neutrino spectrum. In the case of supersymmetry, loop corrections can also contribute to neutrino masses, which lead to the possibility to generate the neutrino spectrum by introducing just one right-handed neutrino. To be realistic, MSSM suffers from the mu problem and other phenomenological difficulties, so we extend NMSSM (the MSSM with a singlet S) by introducing one single right-handed neutrino superfield (N) and relevant phenomenology is discussed

  9. Decaying neutrinos: The long way to isotropy

    SciTech Connect

    Basboell, Anders [Department of Physics and Astronomy, University of Sussex, Brighton, BN1 9QH (United Kingdom); Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Bjaelde, Ole Eggers [Institut fuer Theoretische Physik E, RWTH Aachen University, D-52056 Aachen (Germany); Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark)

    2010-06-15

    We investigate a scenario in which neutrinos are coupled to a pseudoscalar degree of freedom {phi} and where decays {nu}{sub 1{yields}{nu}2}+{phi} and inverse decays are the responsible mechanism for obtaining equilibrium. In this context we discuss the implication of the invisible neutrino decay on the neutrino-pseudoscalar coupling constant and the neutrino lifetime. Assuming the realistic scenario of a thermal background of neutrinos and pseudoscalar we update the bound on the (off-diagonal) neutrino-pseudoscalar coupling constant to g<2.6x10{sup -13} and the bound on the neutrino lifetime to {tau}>1x10{sup 13} s. Furthermore we confirm analytically that kinetic equilibrium is delayed by two Lorentz {gamma} factors--one for time dilation of the (decaying) neutrino lifetime and one from the opening angle. We have also confirmed this behavior numerically.

  10. Big World of Small Neutrinos Hitoshi Murayama

    E-print Network

    Murayama, Hitoshi

    colloquium 2 Neutrinos are Everywhere #12;Harvard colloquium 3 "Wimpy and Abundant" Neutrinos are Everywhere-Kamiokande (SuperK) · Kamioka Mine in central Japan · ~1000m underground · 50kt water · Inner Detector ­ 11,200 PMTs

  11. Particle physics confronts the solar neutrino problem

    SciTech Connect

    Pal, P.B.

    1991-06-01

    This review has four parts. In Part I, we describe the reactions that produce neutrinos in the sun and the expected flux of those neutrinos on the earth. We then discuss the detection of these neutrinos, and how the results obtained differ from the theoretical expectations, leading to what is known as the solar neutrino problem. In Part II, we show how neutrino oscillations can provide a solution to the solar neutrino problem. This includes vacuum oscillations, as well as matter enhanced oscillations. In Part III, we discuss the possibility of time variation of the neutrino flux and how a magnetic moment of the neutrino can solve the problem. WE also discuss particle physics models which can give rise to the required values of magnetic moments. In Part IV, we present some concluding remarks and outlook for the recent future.

  12. Neutrinos and cosmology: A lifetime relationship

    NASA Astrophysics Data System (ADS)

    Serpico, Pasquale D.

    2009-06-01

    We consider the example of neutrino decays to illustrate the profound relation between laboratory neutrino physics and cosmology. Two case studies are presented: In the first one, we show how the high precision cosmic microwave background spectral data collected by the FIRAS instrument on board of COBE, when combined with Lab data, have greatly changed bounds on the radiative neutrino lifetime. In the second case, we speculate on the consequence for neutrino physics of the cosmological detection of neutrino masses even as small as ~0.06 eV, the lower limit guaranteed by neutrino oscillation experiments. We show that a detection at that level would improve by many orders of magnitude the existing limits on neutrino lifetime, and as a consequence on some models of neutrino secret interactions.

  13. Reactor neutrino experiments: ?13 and beyond

    NASA Astrophysics Data System (ADS)

    Qian, Xin; Wang, Wei

    2014-05-01

    We review the current-generation short-baseline reactor neutrino experiments that have firmly established the third neutrino mixing angle ?13 to be nonzero. The relative large value of ?13 (around 9°) has opened many new and exciting opportunities for future neutrino experiments. Daya Bay experiment with the first measurement of ? m2ee is aiming for a precision measurement of this atmospheric mass-squared splitting with a comparable precision as ? m2? ? from accelerator muon neutrino experiments. JUNO, a next-generation reactor neutrino experiment, is targeting to determine the neutrino mass hierarchy (MH) with medium baselines ( 50 km). Beside these opportunities enabled by the large ?13, the current-generation (Daya Bay, Double Chooz, and RENO) and the next-generation (JUNO, RENO-50, and PROSPECT) reactor experiments, with their unprecedented statistics, are also leading the precision era of the three-flavor neutrino oscillation physics as well as constraining new physics beyond the neutrino Standard Model.

  14. Solar Neutrinos and the Borexino experiment

    NASA Astrophysics Data System (ADS)

    Vignaud, D.

    2015-04-01

    Solar neutrinos are produced in the core of the Sun in different nuclear reactions all based on the conversion of hydrogen into helium, releasing energy and making the Sun shine. Until now, the observation of solar neutrinos has demonstrated: a) the nuclear origin of the Sun's energy; b) that the ve produced were undergoing lepton flavor transformation into v? or v?, the neutrino oscillation mechanism. In the recent years, the Borexino experiment, in the Gran Sasso underground laboratory, has made significant contributions to the solar neutrino spectroscopy: first observation and precision measurement of the 7Be neutrinos, first observation of the pep reaction, stringent limit on CNO neutrinos, observation of 8B neutrinos with a 3 MeV threshold. These measurements reinforce the so-called LMA solution of the neutrino oscillation explaining the solar ve survival probability as a function of energy.

  15. Neutrino Wave Packets in Quantum Field Theory

    E-print Network

    C. Giunti

    2002-06-26

    We present a model of neutrino oscillations in the framework of quantum field theory in which the propagating neutrino and the particles participating to the production and detection processes are described by wave packets. The neutrino state is a superposition of massive neutrino wave packets determined by the production process, as naturally expected from causality. We show that the energies and momenta of the massive neutrino components relevant for neutrino oscillations are in general different from the average energies and momenta of the propagating massive neutrino wave packets, because of the effects of the detection process. Our results confirm the correctness of the standard expression for the oscillation length of extremely relativistic neutrinos and the existence of a coherence length.

  16. Cold Dark Matter, Radiative Neutrino Mass, mu to e gamma, and Neutrinoless Double Beta Decay

    E-print Network

    Jisuke Kubo; Ernest Ma; Daijiro Suematsu

    2006-08-24

    Two of the most important and pressing questions in cosmology and particle physics are: (1) What is the nature of cold dark matter? and (2) Will near-future experiments on neutrinoless double beta decay be able to ascertain that the neutrino is a Majorana particle, i.e. its own antiparticle? We show that these two seemingly unrelated issues are intimately connected if neutrinos acquire mass only because of their interactions with dark matter.

  17. Inverse neutrinoless double beta decay revisited: Neutrinos, Higgs triplets, and a muon collider

    Microsoft Academic Search

    Werner Rodejohann

    2010-01-01

    We revisit the process of inverse neutrinoless double beta decay (e-e--->W-W-) at future linear colliders. The cases of Majorana neutrino and Higgs triplet exchange are considered. We also discuss the processes e-mu--->W-W- and mu-mu--->W-W-, which are motivated by the possibility of muon colliders. For heavy neutrino exchange, we show that masses up to 106 (105)GeV could be probed for ee

  18. Detection of very small neutrino masses in double-beta decay using laser tagging

    Microsoft Academic Search

    M. Danilov; R. DeVoe; A. Dolgolenko; G. Giannini; G. Gratta; P. Picchi; A. Piepke; F. Pietropaolo; P. Vogel; J. L. Vuilleumier; Y. F. Wang; O. Zeldovich

    2000-01-01

    We describe an approach to the study of neutrino masses that combines quantum optics techniques with radiation detectors to obtain unprecedented sensitivity. With it the search for Majorana neutrino masses down to ?10 meV will become accessible. The experimental technique uses the possibility of individually detecting Ba+-ions in the final state of 136Xe double-beta decay via resonant excitation with a

  19. Observation of electron neutrino appearance in a muon neutrino beam.

    PubMed

    Abe, K; Adam, J; Aihara, H; Akiri, T; Andreopoulos, C; Aoki, S; Ariga, A; Ariga, T; Assylbekov, S; Autiero, D; Barbi, M; Barker, G J; Barr, G; Bass, M; Batkiewicz, M; Bay, F; Bentham, S W; Berardi, V; Berger, B E; Berkman, S; Bertram, I; Bhadra, S; Blaszczyk, F D M; Blondel, A; Bojechko, C; Bordoni, S; Boyd, S B; Brailsford, D; Bravar, A; Bronner, C; Buchanan, N; Calland, R G; Caravaca Rodríguez, J; Cartwright, S L; Castillo, R; Catanesi, M G; Cervera, A; Cherdack, D; Christodoulou, G; Clifton, A; Coleman, J; Coleman, S J; Collazuol, G; Connolly, K; Cremonesi, L; Dabrowska, A; Danko, I; Das, R; Davis, S; de Perio, P; De Rosa, G; Dealtry, T; Dennis, S R; Densham, C; Di Lodovico, F; Di Luise, S; Drapier, O; Duboyski, T; Duffy, K; Dufour, F; Dumarchez, J; Dytman, S; Dziewiecki, M; Emery, S; Ereditato, A; Escudero, L; Finch, A J; Floetotto, L; Friend, M; Fujii, Y; Fukuda, Y; Furmanski, A P; Galymov, V; Gaudin, A; Giffin, S; Giganti, C; Gilje, K; Goeldi, D; Golan, T; Gomez-Cadenas, J J; Gonin, M; Grant, N; Gudin, D; Hadley, D R; Haesler, A; Haigh, M D; Hamilton, P; Hansen, D; Hara, T; Hartz, M; Hasegawa, T; Hastings, N C; Hayato, Y; Hearty, C; Helmer, R L; Hierholzer, M; Hignight, J; Hillairet, A; Himmel, A; Hiraki, T; Hirota, S; Holeczek, J; Horikawa, S; Huang, K; Ichikawa, A K; Ieki, K; Ieva, M; Ikeda, M; Imber, J; Insler, J; Irvine, T J; Ishida, T; Ishii, T; Ives, S J; Iyogi, K; Izmaylov, A; Jacob, A; Jamieson, B; Johnson, R A; Jo, J H; Jonsson, P; Jung, C K; Kaboth, A C; Kajita, T; Kakuno, H; Kameda, J; Kanazawa, Y; Karlen, D; Karpikov, I; Kearns, E; Khabibullin, M; Khotjantsev, A; Kielczewska, D; Kikawa, T; Kilinski, A; Kim, J; Kisiel, J; Kitching, P; Kobayashi, T; Koch, L; Kolaceke, A; Konaka, A; Kormos, L L; Korzenev, A; Koseki, K; Koshio, Y; Kreslo, I; Kropp, W; Kubo, H; Kudenko, Y; Kumaratunga, S; Kurjata, R; Kutter, T; Lagoda, J; Laihem, K; Lamont, I; Laveder, M; Lawe, M; Lazos, M; Lee, K P; Licciardi, C; Lindner, T; Lister, C; Litchfield, R P; Longhin, A; Ludovici, L; Macaire, M; Magaletti, L; Mahn, K; Malek, M; Manly, S; Marino, A D; Marteau, J; Martin, J F; Maruyama, T; Marzec, J; Mathie, E L; Matveev, V; Mavrokoridis, K; Mazzucato, E; McCarthy, M; McCauley, N; McFarland, K S; McGrew, C; Metelko, C; Mezzetto, M; Mijakowski, P; Miller, C A; Minamino, A; Mineev, O; Mine, S; Missert, A; Miura, M; Monfregola, L; Moriyama, S; Mueller, Th A; Murakami, A; Murdoch, M; Murphy, S; Myslik, J; Nagasaki, T; Nakadaira, T; Nakahata, M; Nakai, T; Nakamura, K; Nakayama, S; Nakaya, T; Nakayoshi, K; Naples, D; Nielsen, C; Nirkko, M; Nishikawa, K; Nishimura, Y; O'Keeffe, H M; Ohta, R; Okumura, K; Okusawa, T; Oryszczak, W; Oser, S M; Owen, R A; Oyama, Y; Palladino, V; Paolone, V; Payne, D; Pearce, G F; Perevozchikov, O; Perkin, J D; Petrov, Y; Pickard, L J; Pinzon Guerra, E S; Pistillo, C; Plonski, P; Poplawska, E; Popov, B; Posiadala, M; Poutissou, J-M; Poutissou, R; Przewlocki, P; Quilain, B; Radicioni, E; Ratoff, P N; Ravonel, M; Rayner, M A M; Redij, A; Reeves, M; Reinherz-Aronis, E; Retiere, F; Robert, A; Rodrigues, P A; Rojas, P; Rondio, E; Roth, S; Rubbia, A; Ruterbories, D; Sacco, R; Sakashita, K; Sánchez, F; Sato, F; Scantamburlo, E; Scholberg, K; Schwehr, J; Scott, M; Seiya, Y; Sekiguchi, T; Sekiya, H; Sgalaberna, D; Shiozawa, M; Short, S; Shustrov, Y; Sinclair, P; Smith, B; Smith, R J; Smy, M; Sobczyk, J T; Sobel, H; Sorel, M; Southwell, L; Stamoulis, P; Steinmann, J; Still, B; Suda, Y; Suzuki, A; Suzuki, K; Suzuki, S Y; Suzuki, Y; Szeglowski, T; Tacik, R; Tada, M; Takahashi, S; Takeda, A; Takeuchi, Y; Tanaka, H K; Tanaka, H A; Tanaka, M M; Terhorst, D; Terri, R; Thompson, L F; Thorley, A; Tobayama, S; Toki, W; Tomura, T; Totsuka, Y; Touramanis, C; Tsukamoto, T; Tzanov, M; Uchida, Y; Ueno, K; Vacheret, A; Vagins, M; Vasseur, G; Wachala, T; Waldron, A V; Walter, C W; Wark, D; Wascko, M O; Weber, A; Wendell, R; Wilkes, R J; Wilking, M J; Wilkinson, C; Williamson, Z; Wilson, J R; Wilson, R J; Wongjirad, T; Yamada, Y; Yamamoto, K; Yanagisawa, C; Yen, S; Yershov, N; Yokoyama, M; Yuan, T; Zalewska, A; Zalipska, J; Zambelli, L; Zaremba, K; Ziembicki, M; Zimmerman, E D; Zito, M; Zmuda, J

    2014-02-14

    The T2K experiment has observed electron neutrino appearance in a muon neutrino beam produced 295 km from the Super-Kamiokande detector with a peak energy of 0.6 GeV. A total of 28 electron neutrino events were detected with an energy distribution consistent with an appearance signal, corresponding to a significance of 7.3? when compared to 4.92±0.55 expected background events. In the Pontecorvo-Maki-Nakagawa-Sakata mixing model, the electron neutrino appearance signal depends on several parameters including three mixing angles ?12, ?23, ?13, a mass difference ?m(32)(2) and a CP violating phase ?(CP). In this neutrino oscillation scenario, assuming |?m(32)(2)|=2.4×10(-3)??eV(2), sin(2)?(23)=0.5, and ?m322>0 (?m(32)(2)<0), a best-fit value of sin(2)2?(13)=0.140(-0.032)(+0.038) (0.170(-0.037)(+0.045)) is obtained at ?(CP)=0. When combining the result with the current best knowledge of oscillation parameters including the world average value of ?(13) from reactor experiments, some values of ?(CP) are disfavored at the 90% C.L. PMID:24580687

  20. Evidence of electron neutrino appearance in a muon neutrino beam

    NASA Astrophysics Data System (ADS)

    Abe, K.; Abgrall, N.; Aihara, H.; Akiri, T.; Albert, J. B.; Andreopoulos, C.; Aoki, S.; Ariga, A.; Ariga, T.; Assylbekov, S.; Autiero, D.; Barbi, M.; Barker, G. J.; Barr, G.; Bass, M.; Batkiewicz, M.; Bay, F.; Bentham, S. W.; Berardi, V.; Berger, B. E.; Berkman, S.; Bertram, I.; Beznosko, D.; Bhadra, S.; Blaszczyk, F. d. M.; Blondel, A.; Bojechko, C.; Boyd, S.; Brailsford, D.; Bravar, A.; Bronner, C.; Brook-Roberge, D. G.; Buchanan, N.; Calland, R. G.; Caravaca Rodríguez, J.; Cartwright, S. L.; Castillo, R.; Catanesi, M. G.; Cervera, A.; Cherdack, D.; Christodoulou, G.; Clifton, A.; Coleman, J.; Coleman, S. J.; Collazuol, G.; Connolly, K.; Cremonesi, L.; Curioni, A.; Dabrowska, A.; Danko, I.; Das, R.; Davis, S.; Day, M.; de André, J. P. A. M.; de Perio, P.; De Rosa, G.; Dealtry, T.; Dennis, S.; Densham, C.; Di Lodovico, F.; Di Luise, S.; Dobson, J.; Drapier, O.; Duboyski, T.; Dufour, F.; Dumarchez, J.; Dytman, S.; Dziewiecki, M.; Dziomba, M.; Emery, S.; Ereditato, A.; Escudero, L.; Finch, A. J.; Frank, E.; Friend, M.; Fujii, Y.; Fukuda, Y.; Furmanski, A.; Galymov, V.; Gaudin, A.; Giffin, S.; Giganti, C.; Gilje, K.; Golan, T.; Gomez-Cadenas, J. J.; Gonin, M.; Grant, N.; Gudin, D.; Hadley, D. R.; Haesler, A.; Haigh, M. D.; Hamilton, P.; Hansen, D.; Hara, T.; Hartz, M.; Hasegawa, T.; Hastings, N. C.; Hayato, Y.; Hearty, C.; Helmer, R. L.; Hierholzer, M.; Hignight, J.; Hillairet, A.; Himmel, A.; Hiraki, T.; Hirota, S.; Holeczek, J.; Horikawa, S.; Huang, K.; Ichikawa, A. K.; Ieki, K.; Ieva, M.; Ikeda, M.; Imber, J.; Insler, J.; Irvine, T. J.; Ishida, T.; Ishii, T.; Ives, S. J.; Iyogi, K.; Izmaylov, A.; Jacob, A.; Jamieson, B.; Johnson, R. A.; Jo, J. H.; Jonsson, P.; Joo, K. K.; Jung, C. K.; Kaboth, A.; Kaji, H.; Kajita, T.; Kakuno, H.; Kameda, J.; Kanazawa, Y.; Karlen, D.; Karpikov, I.; Kearns, E.; Khabibullin, M.; Khanam, F.; Khotjantsev, A.; Kielczewska, D.; Kikawa, T.; Kilinski, A.; Kim, J. Y.; Kim, J.; Kim, S. B.; Kirby, B.; Kisiel, J.; Kitching, P.; Kobayashi, T.; Kogan, G.; Kolaceke, A.; Konaka, A.; Kormos, L. L.; Korzenev, A.; Koseki, K.; Koshio, Y.; Kowalik, K.; Kreslo, I.; Kropp, W.; Kubo, H.; Kudenko, Y.; Kumaratunga, S.; Kurjata, R.; Kutter, T.; Lagoda, J.; Laihem, K.; Laing, A.; Laveder, M.; Lawe, M.; Lazos, M.; Lee, K. P.; Licciardi, C.; Lim, I. T.; Lindner, T.; Lister, C.; Litchfield, R. P.; Longhin, A.; Lopez, G. D.; Ludovici, L.; Macaire, M.; Magaletti, L.; Mahn, K.; Malek, M.; Manly, S.; Marchionni, A.; Marino, A. D.; Marteau, J.; Martin, J. F.; Maruyama, T.; Marzec, J.; Masliah, P.; Mathie, E. L.; Matveev, V.; Mavrokoridis, K.; Mazzucato, E.; McCauley, N.; McFarland, K. S.; McGrew, C.; McLachlan, T.; Messina, M.; Metelko, C.; Mezzetto, M.; Mijakowski, P.; Miller, C. A.; Minamino, A.; Mineev, O.; Mine, S.; Missert, A.; Miura, M.; Monfregola, L.; Moriyama, S.; Mueller, Th. A.; Murakami, A.; Murdoch, M.; Murphy, S.; Myslik, J.; Nagasaki, T.; Nakadaira, T.; Nakahata, M.; Nakai, T.; Nakajima, K.; Nakamura, K.; Nakayama, S.; Nakaya, T.; Nakayoshi, K.; Naples, D.; Nicholls, T. C.; Nielsen, C.; Nirkko, M.; Nishikawa, K.; Nishimura, Y.; O'Keeffe, H. M.; Obayashi, Y.; Ohta, R.; Okumura, K.; Okusawa, T.; Oryszczak, W.; Oser, S. M.; Otani, M.; Owen, R. A.; Oyama, Y.; Pac, M. Y.; Palladino, V.; Paolone, V.; Payne, D.; Pearce, G. F.; Perevozchikov, O.; Perkin, J. D.; Petrov, Y.; Pinzon Guerra, E. S.; Plonski, P.; Poplawska, E.; Popov, B.; Posiadala, M.; Poutissou, J.-M.; Poutissou, R.; Przewlocki, P.; Quilain, B.; Radicioni, E.; Ratoff, P. N.; Ravonel, M.; Rayner, M. A. M.; Reeves, M.; Reinherz-Aronis, E.; Retiere, F.; Robert, A.; Rodrigues, P. A.; Rondio, E.; Roth, S.; Rubbia, A.; Ruterbories, D.; Sacco, R.; Sakashita, K.; Sánchez, F.; Scantamburlo, E.; Scholberg, K.; Schwehr, J.; Scott, M.; Scully, D. I.; Seiya, Y.; Sekiguchi, T.; Sekiya, H.; Sgalaberna, D.; Shibata, M.; Shiozawa, M.; Short, S.; Shustrov, Y.; Sinclair, P.; Smith, B.; Smith, R. J.; Smy, M.; Sobczyk, J. T.; Sobel, H.; Sorel, M.; Southwell, L.; Stamoulis, P.; Steinmann, J.; Still, B.; Suzuki, A.; Suzuki, K.; Suzuki, S. Y.; Suzuki, Y.; Szeglowski, T.; Szeptycka, M.; Tacik, R.; Tada, M.; Takahashi, S.; Takeda, A.; Takeuchi, Y.; Tanaka, H. A.; Tanaka, M. M.; Tanaka, M.; Taylor, I. J.; Terhorst, D.; Terri, R.; Thompson, L. F.; Thorley, A.; Tobayama, S.; Toki, W.; Tomura, T.; Totsuka, Y.; Touramanis, C.; Tsukamoto, T.; Tzanov, M.; Uchida, Y.; Ueno, K.; Vacheret, A.; Vagins, M.; Vasseur, G.; Wachala, T.; Waldron, A. V.; Walter, C. W.; Wark, D.; Wascko, M. O.; Weber, A.; Wendell, R.; Wilkes, R. J.; Wilking, M. J.; Wilkinson, C.; Williamson, Z.; Wilson, J. R.; Wilson, R. J.; Wongjirad, T.; Yamada, Y.; Yamamoto, K.; Yanagisawa, C.; Yen, S.; Yershov, N.; Yokoyama, M.; Yuan, T.; Zalewska, A.; Zambelli, L.; Zaremba, K.; Ziembicki, M.; Zimmerman, E. D.; Zito, M.

    2013-08-01

    The T2K Collaboration reports evidence for electron neutrino appearance at the atmospheric mass splitting, |?m322|?2.4×10-3eV2. An excess of electron neutrino interactions over background is observed from a muon neutrino beam with a peak energy of 0.6 GeV at the Super-Kamiokande (SK) detector 295 km from the beam’s origin. Signal and background predictions are constrained by data from near detectors located 280 m from the neutrino production target. We observe 11 electron neutrino candidate events at the SK detector when a background of 3.3±0.4(syst) events is expected. The background-only hypothesis is rejected with a p value of 0.0009 (3.1?), and a fit assuming ????e oscillations with sin?22?23=1, ?CP=0 and |?m322|=2.4×10-3eV2 yields sin?22?13=0.088-0.039+0.049(stat+syst).

  1. Observation of Electron Neutrino Appearance in a Muon Neutrino Beam

    NASA Astrophysics Data System (ADS)

    Abe, K.; Adam, J.; Aihara, H.; Akiri, T.; Andreopoulos, C.; Aoki, S.; Ariga, A.; Ariga, T.; Assylbekov, S.; Autiero, D.; Barbi, M.; Barker, G. J.; Barr, G.; Bass, M.; Batkiewicz, M.; Bay, F.; Bentham, S. W.; Berardi, V.; Berger, B. E.; Berkman, S.; Bertram, I.; Bhadra, S.; Blaszczyk, F. d. M.; Blondel, A.; Bojechko, C.; Bordoni, S.; Boyd, S. B.; Brailsford, D.; Bravar, A.; Bronner, C.; Buchanan, N.; Calland, R. G.; Caravaca Rodríguez, J.; Cartwright, S. L.; Castillo, R.; Catanesi, M. G.; Cervera, A.; Cherdack, D.; Christodoulou, G.; Clifton, A.; Coleman, J.; Coleman, S. J.; Collazuol, G.; Connolly, K.; Cremonesi, L.; Dabrowska, A.; Danko, I.; Das, R.; Davis, S.; de Perio, P.; De Rosa, G.; Dealtry, T.; Dennis, S. R.; Densham, C.; Di Lodovico, F.; Di Luise, S.; Drapier, O.; Duboyski, T.; Duffy, K.; Dufour, F.; Dumarchez, J.; Dytman, S.; Dziewiecki, M.; Emery, S.; Ereditato, A.; Escudero, L.; Finch, A. J.; Floetotto, L.; Friend, M.; Fujii, Y.; Fukuda, Y.; Furmanski, A. P.; Galymov, V.; Gaudin, A.; Giffin, S.; Giganti, C.; Gilje, K.; Goeldi, D.; Golan, T.; Gomez-Cadenas, J. J.; Gonin, M.; Grant, N.; Gudin, D.; Hadley, D. R.; Haesler, A.; Haigh, M. D.; Hamilton, P.; Hansen, D.; Hara, T.; Hartz, M.; Hasegawa, T.; Hastings, N. C.; Hayato, Y.; Hearty, C.; Helmer, R. L.; Hierholzer, M.; Hignight, J.; Hillairet, A.; Himmel, A.; Hiraki, T.; Hirota, S.; Holeczek, J.; Horikawa, S.; Huang, K.; Ichikawa, A. K.; Ieki, K.; Ieva, M.; Ikeda, M.; Imber, J.; Insler, J.; Irvine, T. J.; Ishida, T.; Ishii, T.; Ives, S. J.; Iyogi, K.; Izmaylov, A.; Jacob, A.; Jamieson, B.; Johnson, R. A.; Jo, J. H.; Jonsson, P.; Jung, C. K.; Kaboth, A. C.; Kajita, T.; Kakuno, H.; Kameda, J.; Kanazawa, Y.; Karlen, D.; Karpikov, I.; Kearns, E.; Khabibullin, M.; Khotjantsev, A.; Kielczewska, D.; Kikawa, T.; Kilinski, A.; Kim, J.; Kisiel, J.; Kitching, P.; Kobayashi, T.; Koch, L.; Kolaceke, A.; Konaka, A.; Kormos, L. L.; Korzenev, A.; Koseki, K.; Koshio, Y.; Kreslo, I.; Kropp, W.; Kubo, H.; Kudenko, Y.; Kumaratunga, S.; Kurjata, R.; Kutter, T.; Lagoda, J.; Laihem, K.; Lamont, I.; Laveder, M.; Lawe, M.; Lazos, M.; Lee, K. P.; Licciardi, C.; Lindner, T.; Lister, C.; Litchfield, R. P.; Longhin, A.; Ludovici, L.; Macaire, M.; Magaletti, L.; Mahn, K.; Malek, M.; Manly, S.; Marino, A. D.; Marteau, J.; Martin, J. F.; Maruyama, T.; Marzec, J.; Mathie, E. L.; Matveev, V.; Mavrokoridis, K.; Mazzucato, E.; McCarthy, M.; McCauley, N.; McFarland, K. S.; McGrew, C.; Metelko, C.; Mezzetto, M.; Mijakowski, P.; Miller, C. A.; Minamino, A.; Mineev, O.; Mine, S.; Missert, A.; Miura, M.; Monfregola, L.; Moriyama, S.; Mueller, Th. A.; Murakami, A.; Murdoch, M.; Murphy, S.; Myslik, J.; Nagasaki, T.; Nakadaira, T.; Nakahata, M.; Nakai, T.; Nakamura, K.; Nakayama, S.; Nakaya, T.; Nakayoshi, K.; Naples, D.; Nielsen, C.; Nirkko, M.; Nishikawa, K.; Nishimura, Y.; O'Keeffe, H. M.; Ohta, R.; Okumura, K.; Okusawa, T.; Oryszczak, W.; Oser, S. M.; Owen, R. A.; Oyama, Y.; Palladino, V.; Paolone, V.; Payne, D.; Pearce, G. F.; Perevozchikov, O.; Perkin, J. D.; Petrov, Y.; Pickard, L. J.; Pinzon Guerra, E. S.; Pistillo, C.; Plonski, P.; Poplawska, E.; Popov, B.; Posiadala, M.; Poutissou, J.-M.; Poutissou, R.; Przewlocki, P.; Quilain, B.; Radicioni, E.; Ratoff, P. N.; Ravonel, M.; Rayner, M. A. M.; Redij, A.; Reeves, M.; Reinherz-Aronis, E.; Retiere, F.; Robert, A.; Rodrigues, P. A.; Rojas, P.; Rondio, E.; Roth, S.; Rubbia, A.; Ruterbories, D.; Sacco, R.; Sakashita, K.; Sánchez, F.; Sato, F.; Scantamburlo, E.; Scholberg, K.; Schwehr, J.; Scott, M.; Seiya, Y.; Sekiguchi, T.; Sekiya, H.; Sgalaberna, D.; Shiozawa, M.; Short, S.; Shustrov, Y.; Sinclair, P.; Smith, B.; Smith, R. J.; Smy, M.; Sobczyk, J. T.; Sobel, H.; Sorel, M.; Southwell, L.; Stamoulis, P.; Steinmann, J.; Still, B.; Suda, Y.; Suzuki, A.; Suzuki, K.; Suzuki, S. Y.; Suzuki, Y.; Szeglowski, T.; Tacik, R.; Tada, M.; Takahashi, S.; Takeda, A.; Takeuchi, Y.; Tanaka, H. K.; Tanaka, H. A.; Tanaka, M. M.; Terhorst, D.; Terri, R.; Thompson, L. F.; Thorley, A.; Tobayama, S.; Toki, W.; Tomura, T.; Totsuka, Y.; Touramanis, C.; Tsukamoto, T.; Tzanov, M.; Uchida, Y.; Ueno, K.; Vacheret, A.; Vagins, M.; Vasseur, G.; Wachala, T.; Waldron, A. V.; Walter, C. W.; Wark, D.; Wascko, M. O.; Weber, A.; Wendell, R.; Wilkes, R. J.; Wilking, M. J.; Wilkinson, C.; Williamson, Z.; Wilson, J. R.; Wilson, R. J.; Wongjirad, T.; Yamada, Y.; Yamamoto, K.; Yanagisawa, C.; Yen, S.; Yershov, N.; Yokoyama, M.; Yuan, T.; Zalewska, A.; Zalipska, J.; Zambelli, L.; Zaremba, K.; Ziembicki, M.; Zimmerman, E. D.; Zito, M.; ?muda, J.; T2K Collaboration

    2014-02-01

    The T2K experiment has observed electron neutrino appearance in a muon neutrino beam produced 295 km from the Super-Kamiokande detector with a peak energy of 0.6 GeV. A total of 28 electron neutrino events were detected with an energy distribution consistent with an appearance signal, corresponding to a significance of 7.3? when compared to 4.92±0.55 expected background events. In the Pontecorvo-Maki-Nakagawa-Sakata mixing model, the electron neutrino appearance signal depends on several parameters including three mixing angles ?12, ?23, ?13, a mass difference ?m322 and a CP violating phase ?CP. In this neutrino oscillation scenario, assuming |?m322|=2.4×10-3 eV2, sin2?23=0.5, and ?m322>0 (?m322<0), a best-fit value of sin22?13=0.140-0.032+0.038 (0.170-0.037+0.045) is obtained at ?CP=0. When combining the result with the current best knowledge of oscillation parameters including the world average value of ?13 from reactor experiments, some values of ?CP are disfavored at the 90% C.L.

  2. Sterile neutrinos in the early universe

    SciTech Connect

    Malaney, R.A. (Lawrence Livermore National Lab., CA (USA)); Fuller, G.M. (California Univ., San Diego, La Jolla, CA (USA). Dept. of Physics)

    1990-11-14

    We discuss the role played by right-handed sterile neutrinos in the early universe. We show how well known {sup 4}He constraint on the number of relativistic degrees of freedom at early times limits the equilibration of the right handed neutrino sea with the background plasma. We discuss how this allows interesting constraints to be placed on neutrino properties. In particular, a new limit on the Dirac mass of the neutrino is presented. 12 refs.

  3. Overview of progress in neutrino scattering measurements

    E-print Network

    M. Sorel

    2007-10-22

    Recent progress in neutrino scattering experiments with few GeV neutrino beams is reviewed, focusing on new experimental input since the beginning of the NuInt workshop series in 2001. Progress in neutrino quasi-elastic scattering, resonance production, coherent pion production, scattering in the transition region between the resonance and deep inelastic regimes, and nuclear effects in neutrino-nucleus scattering, is discussed.

  4. Collective flavor transitions of supernova neutrinos

    NASA Astrophysics Data System (ADS)

    Sigl, Günter; Tomàs, Ricard; Esteban-Pretel, Andreu; Pastor, Sergio; Mirizzi, Alessandro; Raffelt, Georg G.; Serpico, Pasquale D.

    2009-03-01

    We give a very brief overview of collective effects in neutrino oscillations in core collapse supernovae where refractive effects of neutrinos on themselves can considerably modify flavor oscillations, with possible repercussions for future supernova neutrino detection. We discuss synchronized and bipolar oscillations, the role of energy and angular neutrino modes, as well as three-flavor effects. We close with a short summary and some open questions.

  5. Earth Matter Effect on Democratic Neutrinos

    E-print Network

    Dmitry Zhuridov

    2014-08-30

    The neutrino propagation through the Earth is investigated in the framework of the democratic neutrino theory. In this theory the neutrino mixing angle theta-1-3 is approximately determined, which allows one to make a well defined neutrino oscillogram driven by the 1-3 mixing in the matter of the Earth. Significant differences in this oscillogram from the case of models with relatively small theta-1-3 are discussed.

  6. New results from the AMANDA Neutrino Telescope

    NASA Astrophysics Data System (ADS)

    AMANDA Collaboration; Ackermann, M.; Ahrens, J.; Bai, X.; Bay, R.; Bartelt, M.; Barwick, S. W.; Becka, T.; Becker, J. K.; Becker, K. H.; Bernardini, E.; Bertrand, D.; Boersma, D. J.; Böser, S.; Botner, O.; Bouchta, A.; Bouhali, O.; Braun, J.; Burgess, C.; Burgess, T.; Castermans, T.; Chen, A.; Chirkin, D.; Collin, B.; Conrad, J.; Cooley, J.; Cowen, D. F.; Davour, A.; de Clercq, C.; De Young, T.; Desiati, P.; Ekström, P.; Feser, T.; Gaisser, T. K.; Ganugapati, R.; Geenen, H.; Gerhardt, L.; Groß, A.; Goldschmidt, A.; Hallgren, A.; Halzen, F.; Hanson, K.; Hardtke, D.; Hardtke, R.; Harenberg, T.; Hauschildt, T.; Helbing, K.; Hellwig, M.; Herquet, P.; Hill, G. C.; Hodges, J.; Hubert, D.; Hughey, B.; Hulth, P. O.; Hultqvist, K.; Hundertmark, S.; Jacobsen, J.; Kampert, K. H.; Karle, A.; Kelley, J. L.; Kestel, M.; Kohnen, G.; Köpke, L.; Kowalski, M.; Krasberg, M.; Kuehn, K.; Leich, H.; Leuthold, M.; Liubarsky, I.; Lundberg, J.; Madsen, J.; Marciniewski, P.; Matis, H. S.; McParland, C. P.; Messarius, T.; Minaeva, Y.; Mio?inovi?, P.; Morse, R.; Münich, K.; Nam, J. K.; Nahnhauer, R.; Neunhöffer, T.; Niessen, P.; Nygren, D. R.; Ögelman, H.; Olbrechts, Ph.; Pérez de Los Heros, C.; Pohl, A. C.; Porrata, R.; Price, P. B.; Przybylski, G. T.; Rawlins, K.; Resconi, E.; Rhode, W.; Ribordy, M.; Richter, S.; Rodríguez Martino, J.; Sander, H. G.; Schinarakig, K.; Schlenstedt, S.; Schneider, D.; Schwarz, R.; Silvestri, A.; Solarz, M.; Spiczak, G. M.; Spiering, C.; Stamatikos, M.; Steele, D.; Steffen, P.; Stokstad, R. G.; Sulanke, K. H.; Taboada, I.; Tarasova, O.; Thollander, L.; Tilav, S.; Wagner, W.; Walck, C.; Walter, M.; Wang, Y. R.; Wendt, C.; Wiebusch, C. H.; Wischnewski, R.; Wissing, H.; Woschnagg, K.; Yodh, G.

    2005-08-01

    The Antarctic Muon and Neutrino Detector Array (AMANDA) is a ?erenkov telescope which uses the south polar ice cap to search for neutrinos from extraterrestrial sources. We present a preliminary reconstruction of the energy spectrum of atmospheric neutrinos above a few TeV and several recent results on searches for high-energy astrophysical neutrinos, both non-localized and emitted by point-like sources.

  7. The Lake Baikal neutrino experiment: selected results

    E-print Network

    BAIKAL Collaboration; V. Balkanov

    2000-01-10

    We review the present status of the lake Baikal Neutrino Experiment and present selected physical results gained with the consequetive stages of the stepwise increasing detector: from NT-36 to NT-96. Results cover atmospheric muons, neutrino events, very high energy neutrinos, search for neutrino events from WIMP annihilation, search for magnetic monopoles and environmental studies. We also describe an air Cherenkov array developed for the study of angular resolution of NT-200.

  8. The Baikal Neutrino Telescope: Results, Plans, Lessons

    E-print Network

    Spiering, C; Balkanov, V; Belolaptikov, I A; Bezrukov, L; Budnev, N; Chensky, A G; Chernov, D; Danilchenko, I A; Dzhilkibaev, A; Domogatsky, G; Dyachok, A; Gaponenko, O N; Gress, O A; Gress, T; Klabukov, A; Klimov, A; Klimushin, S; Konischev, K; Koshechkin, A P; Kulepov, V; Kuzmichev, L; Kuznetsov, V; Lubsandorzhiev, B; Mikheyev, S; Milenin, M; Mirgazov, R; Moseiko, N; Osipova, E; Panfilov, A; Pankov, G; Pankov, L V; Parfenov, Yu; Pavlov, A; Pliskovsky, E; Pokhil, P; Polecshuk, V; Popova, E; Prosin, V; Rosanov, M; Rubtzov, V; Semeney, Yu; Shaibonov, B; Tarashansky, B; Vasiliev, R; Vyatchin, E; Wischnewski, R; Yashin, I; Zhukov, V; Spiering, Christian

    2004-01-01

    We review recent results on the search for high energy extraterrestrial neutrinos, neutrinos induced by WIMP annihilation and neutrinos coincident with Gamma Ray Bursts as obtained with the Baikal neutrino telescope NT-200. We describe the moderate upgrade of NT-200 towards a ~10 Mton scale detector NT-200+. We finally draw a few lessons from our experience which may be of use for other underwater experiments.

  9. The Baikal Neutrino Telescope: Results, Plans, Lessons

    E-print Network

    Christian Spiering; for the BAIKAL Collaboration

    2004-04-05

    We review recent results on the search for high energy extraterrestrial neutrinos, neutrinos induced by WIMP annihilation and neutrinos coincident with Gamma Ray Bursts as obtained with the Baikal neutrino telescope NT-200. We describe the moderate upgrade of NT-200 towards a ~10 Mton scale detector NT-200+. We finally draw a few lessons from our experience which may be of use for other underwater experiments.

  10. Neutrino magnetic moment in a magnetized plasma

    E-print Network

    N. V. Mikheev; E. N. Narynskaya

    2010-11-08

    The contribution of a magnetized plasma to the neutrino magnetic moment is calculated. It is shown that only part of the additional neutrino energy in magnetized plasma connecting with its spin and magnetic field strength defines the neutrino magnetic moment. It is found that the presence of magnetized plasma does not lead to the considerable increase of the neutrino magnetic moment in contrast to the results presented in literature previously.

  11. Evidence for Oscillation of Atmospheric Neutrinos

    Microsoft Academic Search

    Henry Sobel; T. Hayakawa; E. Ichihara; K. Inoue; K. Ishihara; H. Ishino; Y. Itow; T. Kajita; J. Kameda; S. Kasuga; K. Kobayashi; Y. Kobayashi; Y. Koshio; M. Miura; M. Nakahata; S. Nakayama; A. Okada; K. Okumura; N. Sakurai; M. Shiozawa; Y. Suzuki; Y. Takeuchi; Y. Totsuka; S. Yamada; M. Earl; A. Habig; E. Kearns; M. D. Messier; K. Scholberg; J. L. Stone; L. R. Sulak; C. W. Walter; M. Goldhaber; T. Barszczxak; D. Casper; W. Gajewski; P. G. Halverson; J. Hsu; W. R. Kropp; L. R. Price; F. Reines; M. Smy; M. R. Vagins; K. S. Ganezer; W. E. Keig; R. W. Ellsworth; S. Tasaka; J. W. Flanagan; A. Kibayashi; J. G. Learned; S. Matsuno; V. J. Stenger; D. Takemori; T. Ishii; J. Kanzaki; T. Kobayashi; S. Mine; K. Nakamura; K. Nishikawa; Y. Oyama; A. Sakai; M. Sakuda; O. Sasaki; S. Echigo; M. Kohama; A. Suzuki; T. J. Haines; E. Blaufuss; B. K. Kim; R. Sanford; R. Svoboda; M. L. Chen; Z. Conner; J. A. Goodman; G. W. Sullivan; J. Hill; C. K. Jung; K. Martens; C. Mauger; C. McGrew; E. Sharkey; B. Viren; C. Yanagisawa; W. Doki; K. Miyano; H. Okazawa; C. Saji; M. Takahata; Y. Nagashima; M. Takita; T. Yamaguchi; M. Yoshida; S. B. Kim; M. Etoh; K. Fujita; A. Hasegawa; T. Hasegawa; S. Hatakeyama; T. Iwamoto; M. Koga; T. Maruyama; H. Ogawa; J. Shirai; F. Tsushima; M. Koshiba; M. Nemoto; K. Nishijima; T. Futagami; Y. Hayato; Y. Kanaya; K. Kaneyuki; Y. Watanabe; D. Kielczewska; R. A. Doyle; J. S. George; A. L. Stachyra; L. L. Wai; R. J. Wilkes; K. K. Young

    1998-01-01

    We present an analysis of atmospheric neutrino data from a 33.0 kton yr (535-day) exposure of the Super-Kamiokande detector. The data exhibit a zenith angle dependent deficit of muon neutrinos which is inconsistent with expectations based on calculations of the atmospheric neutrino flux. Experimental biases and uncertainties in the prediction of neutrino fluxes and cross sections are unable to explain

  12. From Neutrino Factory to Muon Collider

    SciTech Connect

    Geer, S.; /Fermilab

    2010-01-01

    Both Muon Colliders and Neutrino Factories require a muon source capable of producing and capturing {Omicron}(10{sup 21}) muons/year. This paper reviews the similarities and differences between Neutrino Factory and Muon Collider accelerator complexes, the ongoing R&D needed for a Muon Collider that goes beyond Neutrino Factory R&D, and some thoughts about how a Neutrino Factory on the CERN site might eventually be upgraded to a Muon Collider.

  13. Neutrinos and Non-proliferation in Europe

    E-print Network

    Cribier, Michel

    2006-01-01

    Triggered by the demand of the IAEA, neutrino physicists in Europe involved with the Double Chooz experiment are studying the potential of neutrino detection to monitor nuclear reactors. In particular a new set of experiments at the ILL is planned to improve the knowledge of the neutrino spectrum emitted in the fission of 235U and 239Pu.

  14. Best-Bet Astrophysical Neutrino Sources

    E-print Network

    Charles D. Dermer

    2006-11-06

    Likely astrophysical sources of detectable high-energy (>> TeV) neutrinos are considered. Based on gamma-ray emission properties, the most probable sources of neutrinos are argued to be GRBs, blazars, microquasars, and supernova remnants. Diffuse neutrino sources are also briefly considered.

  15. Radiochemical solar neutrino experiments, 'successful and otherwise'

    Microsoft Academic Search

    Richard L. Hahn

    2008-01-01

    Over the years, several different radiochemical systems have been proposed as solar neutrino detectors. Of these, two achieved operating status and obtained important results that helped to define the current field of neutrino physics: the first solar-neutrino experiment, the Chlorine Detector (37Cl) that was developed by chemist Raymond Davis and colleagues at the Homestake Mine, and the subsequent Gallium (71Ga)

  16. Radiochemical solar neutrino experiments, ‘successful and otherwise’

    Microsoft Academic Search

    Richard L Hahn

    2008-01-01

    Over the years, several different radiochemical systems have been proposed as solar neutrino detectors. Of these, two achieved operating status and obtained important results that helped to define the current field of neutrino physics: the first solar-neutrino experiment, the Chlorine Detector (37Cl) that was developed by chemist Raymond Davis and colleagues at the Homestake Mine, and the subsequent Gallium (71Ga)

  17. Low energy atmospheric muon neutrinos in MACRO

    Microsoft Academic Search

    M. Spurio

    1998-01-01

    The flux of low energy neutrinos (~ 4 GeV) has been studied with the MACRO detector at Gran Sasso via the detection of muon neutrinos interactions inside the apparatus, and of upward-going stopping muons. Data collected in ~3 y with the full apparatus were analyzed. The results are compatible with a deficit of the flux of atmospheric muon neutrinos from

  18. Nonadiabatic three-neutrino oscillations in matter

    NASA Astrophysics Data System (ADS)

    D'olivo, J. C.; Oteo, J. A.

    1996-07-01

    Oscillations of three neutrinos in matter are analyzed by using the Magnus expansion for the time-evolution operator. We derive a simple expression for the electron-neutrino survival probability which is applied to the examination of the effect of a third neutrino on the nonadiabatic flavor transformations.

  19. Short-BaseLine Electron Neutrino Disappearance

    E-print Network

    Carlo Giunti; Marco Laveder

    2010-12-20

    We analyzed the electron neutrino data of the Gallium radioactive source experiments and the electron antineutrino data of the reactor Bugey and Chooz experiments in terms of neutrino oscillations. We found a hint of a CPT-violating asymmetry of the effective neutrino and antineutrino mixing angles.

  20. Lectures on Neutrino Astronomy: Theory and Experiment

    E-print Network

    F. Halzen

    1998-10-22

    1. Overview of neutrino astronomy: multidisciplinary science. 2. Cosmic accelerators: the highest energy cosmic rays. 3. Neutrino beam dumps: supermassive black holes and gamma ray bursts. 4. Neutrino telescopes: water and ice. 5. Indirect dark matter detection. 6. Towards kilometer-scale detectors.

  1. Multipole expansion method for supernova neutrino oscillations

    NASA Astrophysics Data System (ADS)

    Duan, Huaiyu; Shalgar, Shashank

    2014-10-01

    We demonstrate a multipole expansion method to calculate collective neutrino oscillations in supernovae using the neutrino bulb model. We show that it is much more efficient to solve multi-angle neutrino oscillations in multipole basis than in angle basis. The multipole expansion method also provides interesting insights into multi-angle calculations that were accomplished previously in angle basis.

  2. Multipole expansion method for supernova neutrino oscillations

    E-print Network

    Huaiyu Duan; Shashank Shalgar

    2014-12-24

    We demonstrate a multipole expansion method to calculate collective neutrino oscillations in supernovae using the neutrino bulb model. We show that it is much more efficient to solve multi-angle neutrino oscillations in multipole basis than in angle basis. The multipole expansion method also provides interesting insights into multi-angle calculations that were accomplished previously in angle basis.

  3. ANTARES: The first undersea neutrino telescope

    Microsoft Academic Search

    M. Ageron; J. A. Aguilar; I. Al Samarai; A. Albert; F. Ameli; M. André; M. Anghinolfi; G. Anton; S. Anvar; M. Ardid; K. Arnaud; E. Aslanides; A. C. Assis Jesus; T. Astraatmadja; J.-J. Aubert; R. Auer; E. Barbarito; B. Baret; S. Basa; M. Bazzotti; Y. Becherini; J. Beltramelli; A. Bersani; V. Bertin; S. Beurthey; S. Biagi; C. Bigongiari; M. Billault; R. Blaes; C. Bogazzi; N. de Botton; M. Bou-Cabo; B. Boudahef; M. C. Bouwhuis; A. M. Brown; J. Brunner; J. Busto; L. Caillat; A. Calzas; F. Camarena; A. Capone; L. Caponetto; C. Cârloganu; G. Carminati; E. Carmona; J. Carr; P. H. Carton; B. Cassano; E. Castorina; S. Cecchini; A. Ceres; Th. Chaleil; Ph. Charvis; P. Chauchot; T. Chiarusi; M. Circella; C. Compère; R. Coniglione; X. Coppolani; A. Cosquer; H. Costantini; N. Cottini; P. Coyle; S. Cuneo; C. Curtil; C. D'Amato; G. Damy; R. van Dantzig; G. De Bonis; G. Decock; M. P. Decowski; I. Dekeyser; E. Delagnes; F. Desages-Ardellier; A. Deschamps; J.-J. Destelle; F. Di Maria; B. Dinkespiler; C. Distefano; J.-L. Dominique; C. Donzaud; D. Dornic; Q. Dorosti; J.-F. Drogou; D. Drouhin; F. Druillole; D. Durand; R. Durand; T. Eberl; U. Emanuele; J. J. Engelen; J.-P. Ernenwein; S. Escoffier; E. Falchini; S. Favard; F. Fehr; F. Feinstein; M. Ferri; S. Ferry; C. Fiorello; V. Flaminio; F. Folger; U. Fritsch; J.-L. Fuda; S. Galatá; S. Galeotti; P. Gay; F. Gensolen; G. Giacomelli; C. Gojak; J. P. Gómez-González; Ph. Goret; K. Graf; G. Guillard; G. Halladjian; G. Hallewell; H. van Haren; B. Hartmann; A. J. Heijboer; E. Heine; Y. Hello; S. Henry; J. J. Hernández-Rey; B. Herold; J. Hößl; J. Hogenbirk; C. C. Hsu; J. R. Hubbard; M. Jaquet; M. Jaspers; M. de Jong; D. Jourde; M. Kadler; N. Kalantar-Nayestanaki; O. Kalekin; A. Kappes; T. Karg; S. Karkar; M. Karolak; U. Katz; P. Keller; P. Kestener; E. Kok; H. Kok; P. Kooijman; C. Kopper; A. Kouchner; W. Kretschmer; A. Kruijer; S. Kuch; V. Kulikovskiy; D. Lachartre; H. Lafoux; P. Lagier; R. Lahmann; C. Lahonde-Hamdoun; P. Lamare; G. Lambard; J.-C. Languillat; G. Larosa; J. Lavalle; Y. Le Guen; H. Le Provost; A. Levansuu; D. Lefèvre; T. Legou; G. Lelaizant; C. Lévéque; G. Lim; D. Lo Presti; H. Loehner; S. Loucatos; F. Louis; F. Lucarelli; V. Lyashuk; P. Magnier; S. Mangano; A. Marcel; M. Marcelin; A. Margiotta; J. A. Martinez-Mora; R. Masullo; F. Mazéas; A. Mazure; A. Meli; M. Melissas; E. Migneco; M. Mongelli; T. Montaruli; M. Morganti; L. Moscoso; H. Motz; M. Musumeci; C. Naumann; M. Naumann-Godo; M. Neff; V. Niess; G. J. L. Nooren; J. E. J. Oberski; C. Olivetto; N. Palanque-Delabrouille; D. Palioselitis; R. Papaleo; G. E. P?v?la?; K. Payet; P. Payre; H. Peek; J. Petrovic; P. Piattelli; N. Picot-Clemente; C. Picq; Y. Piret; J. Poinsignon; V. Popa; T. Pradier; E. Presani; G. Prono; C. Racca; G. Raia; J. van Randwijk; D. Real; C. Reed; F. Réthoré; P. Rewiersma; G. Riccobene; C. Richardt; R. Richter; J. S. Ricol; V. Rigaud; V. Roca; K. Roensch; J.-F. Rolin; A. Rostovtsev; A. Rottura; J. Roux; M. Rujoiu; M. Ruppi; G. V. Russo; F. Salesa; K. Salomon; P. Sapienza; F. Schmitt; F. Schöck; J.-P. Schuller; F. Schüssler; D. Sciliberto; R. Shanidze; E. Shirokov; F. Simeone; A. Sottoriva; A. Spies; T. Spona; M. Spurio; J. J. M. Steijger; Th. Stolarczyk; K. Streeb; L. Sulak; M. Taiuti; C. Tamburini; C. Tao; L. Tasca; G. Terreni; D. Tezier; S. Toscano; F. Urbano; P. Valdy; B. Vallage; V. van Elewyck; G. Vannoni; M. Vecchi; G. Venekamp; B. Verlaat; P. Vernin; E. Virique; G. de Vries; R. van Wijk; G. Wijnker; G. Wobbe; E. de Wolf; Y. Yakovenko; H. Yepes; D. Zaborov; H. Zaccone; J. D. Zornoza; J. Zúñiga

    2011-01-01

    The ANTARES Neutrino Telescope was completed in May 2008 and is the first operational Neutrino Telescope in the Mediterranean Sea. The main purpose of the detector is to perform neutrino astronomy and the apparatus also offers facilities for marine and Earth sciences. This paper describes the design, the construction and the installation of the telescope in the deep sea, offshore

  4. The Renaissance of Neutrino Interaction Physics

    SciTech Connect

    Gallagher, Hugh R. [Tufts University, Medford, MA (United States)

    2009-12-17

    The advent of high intensity neutrino beams for neutrino oscillation experiments has produced a resurgence of interest in neutrino interaction physics. Recent experiments have been revisiting topics not studied since the bubble chamber era, and are exploring many interesting questions at the boundaries of particle and nuclear physics.

  5. Detection of supernova neutrinos with neutrino-iron scattering

    SciTech Connect

    Samana, A. R.; Bertulani, C. A. [Department of Physics, Texas A and M University Commerce, P. O. Box 3011, Commerce, 75429 Texas (United States)

    2008-08-15

    The {nu}{sub e}-{sup 56}Fe cross section is evaluated in the projected quasiparticle random phase approximation (PQRPA). This model solves the puzzle observed in RPA for nuclei with mass around {sup 12}C, because it is the only RPA model that treats the Pauli Principle correctly. The cross sections as a function of the incident neutrino energy are compared with recent theoretical calculations of similar models. The average cross section weighted with the flux spectrum yields a good agreement with the experimental data. The expected number of events in the detection of supernova neutrinos is calculated for the LVD detector, leading to an upper limit for the electron neutrino energy of particular importance in this experiment.

  6. Leptogenesis Via Neutrino Production During Higgs Relaxation

    E-print Network

    Pearce, Lauren; Kusenko, Alexander; Peloso, Marco

    2015-01-01

    During inflation, scalar fields, including the Higgs boson, may acquire a nonzero vacuum expectation value, which must later relax to the equilibrium value during reheating. In the presence of the time-dependent condensate, the vacuum state can evolve into a state with a nonzero particle number. We show that, in the presence of lepton number violation in the neutrino sector, the particle production can explain the observed matter-antimatter asymmetry of the universe. We find that this form of leptogenesis is particularly effective when the Higgs condensate decays rapidly and at low reheat temperature. As part of the calculation, we present some exact results for the Bogoliubov transformations for Majorana fermions with a nonzero time-dependent chemical potential, in addition to a time-dependent mass.

  7. The Search for Neutrino Oscillations

    NASA Astrophysics Data System (ADS)

    Gershun, Daniel

    2011-01-01

    Neutrinos offer insight into such fundamental questions as the dominance of matter over antimatter, the dynamics of supernovae, and the large scale structure of the universe. NOvA (NUMI Off-axis Neutrino Oscillations) is an experiment that will measure crucial neutrino properties using a Near Detector at Fermilab, where the neutrinos are generated in the NuMI beam, and a large Far Detector in Ash River, MN, 735 km from Fermilab. The main objective of this experiment is the measurement of the parameters associated with the oscillation of muon to electron neutrinos. Indiana University with funding from the NSF and DOE are responsible for building and testing the water-cooled heat sinks required for the thermal and environmental control of the Avalanche Photodiodes used in the light detection generated in the Liquid Scintillator. The heat sinks have a brass body with a TEC chip that cools the APD to -15 C. The water system that conducts the 5 W generated by the thermal control has been designed to withstand a maximum pressure of 100 psi. Several of the construction techniques and QC tests performed will be described.

  8. Muon neutrino disappearance at MINOS

    SciTech Connect

    Armstrong, R.; /Indiana U.

    2009-08-01

    A strong case has been made by several experiments that neutrinos oscillate, although important questions remain as to the mechanisms and precise values of the parameters. In the standard picture, two parameters describe the nature of how the neutrinos oscillate: the mass-squared difference between states and the mixing angle. The purpose of this thesis is to use data from the MINOS experiment to precisely measure the parameters associated with oscillations first observed in studies of atmospheric neutrinos. MINOS utilizes two similar detectors to observe the oscillatory nature of neutrinos. The Near Detector, located 1 km from the source, observes the unoscillated energy spectrum while the Far Detector, located 735 km away, is positioned to see the oscillation signal. Using the data in the Near Detector, a prediction of the expected neutrino spectrum at the Far Detector assuming no oscillations is made. By comparing this prediction with the MINOS data, the atmospheric mixing parameters are measured to be {Delta}m{sub 32}{sup 2} = 2.45{sub +0.12}{sup -0.12} x 10{sub -3} eV{sup 2} and sin{sup 2}(2{theta}{sub 32}) = 1.00{sub -0.04}{sup +0.00} (> 0.90 at 90% confidence level).

  9. Expectation values of flavor-neutrino numbers with respect to neutrino-source hadron states --Neutrino oscillations and decay probabilities--

    E-print Network

    Kanji Fujii; Norihito Toyota

    2014-08-09

    On the basis of quantum field theory, we consider a unified description of various processes accompanied by neutrinos, namely weak decays and oscillation processes. The structures of the expectation values of flavor-neutrino numbers with respect to neutrino-source hadron state are investigated. Due to the smallness of neutrino masses, we naturally obtain the old (i.e. pre-mixing) formulas of decay probabilities. Together, it is shown that the oscillation formulas, similar to the usual ones, are applied irrespectively of the details of neutrino-producing processes. The derived oscillation formulas are the same in form as the usually used ones except for the oscillation length.

  10. Corrections to tribimaximal neutrino mixing: Renormalization and Planck scale effects

    SciTech Connect

    Dighe, Amol [Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India); Goswami, Srubabati [Harish-Chandra Research Institute, Chhatnag Road, Jhunsi, Allahabad 211 019 (India); Rodejohann, Werner [Max-Planck-Institut fuer Kernphysik, Postfach 103980, D-69029 Heidelberg (Germany)

    2007-04-01

    We study corrections to tribimaximal (TBM) neutrino mixing from renormalization group (RG) running and from Planck scale effects. We show that while the RG effects are negligible in the standard model (SM), for quasidegenerate neutrinos and large tan{beta} in the minimal supersymmetric standard model (MSSM) all three mixing angles may change significantly. In both these cases, the direction of the modification of {theta}{sub 12} is fixed, while that of {theta}{sub 23} is determined by the neutrino mass ordering. The Planck scale effects can also change {theta}{sub 12} up to a few degrees in either direction for quasidegenerate neutrinos. These effects may dominate over the RG effects in the SM, and in the MSSM with small tan{beta}. The usual constraints on neutrino masses, Majorana phases or tan{beta} stemming from RG running arguments can then be relaxed. We quantify the extent of Planck scale effects on the mixing angles in terms of 'mismatch phases' which break the symmetries leading to TBM. In particular, we show that when the mismatch phases vanish, the mixing angles are not affected in spite of the Planck scale contribution. Similar statements may be made for {mu}-{tau} symmetric mass matrices.

  11. Mirror matter, inverse seesaw neutrino masses and the Higgs mass spectrum

    E-print Network

    M. M. Candido; Y. A. Coutinho; P. C. Malta; J. A. Martins Simões; A. J. Ramalho

    2011-12-09

    In this work we study a mirror model with inverse seesaw neutrino masses in which symmetry breaking scales are fixed from bounds in the neutrino sector. The Higgs sector of the model has two doublets and neutral singlets. The mirror model can be tested at the LHC energies in several aspects. Two very distinctive signatures of the mirror model are a new neutral gauge boson $Z^{\\prime}$, with a high invisible branching ratio, and a heavy Majorana neutrino production through the decay $Z^{\\prime} \\rightarrow N +\\bar \

  12. Mirror matter, inverse seesaw neutrino masses and the Higgs mass spectrum

    E-print Network

    Candido, M M; Malta, P C; Simões, J A Martins; Ramalho, A J

    2011-01-01

    In this work we study a mirror model with inverse seesaw neutrino masses in which symmetry breaking scales are fixed from bounds in the neutrino sector. The Higgs sector of the model has two doublets and neutral singlets. The mirror model can be tested at the LHC energies in several aspects. Two very distinctive signatures of the mirror model are a new neutral gauge boson $Z^{\\prime}$, with a high invisible branching ratio, and a heavy Majorana neutrino production through the decay $Z^{\\prime} \\rightarrow N +\\bar \

  13. Impact of massive tau-neutrinos on primordial nucleosynthesis. Exact calculations

    E-print Network

    A. D. Dolgov; S. H. Hansen; D. V. Semikoz

    1999-02-28

    The influence of a massive Majorana tau-neutrino on primordial nucleosynthesis is rigorously calculated. The system of three integro-differential kinetic equations is solved numerically for the tau-neutrino mass in the interval from 0 to 20 MeV. It is found that the usual assumption of kinetic equilibrium is strongly violated and non-equilibrium corrections considerably amplify the effect. Even a very weak restriction from nucleosynthesis, allowing for one extra massless neutrino species, permits to conclude that m_\

  14. Neutrino mass spectrum and neutrinoless double beta decay

    E-print Network

    H. V. Klapdor-Kleingrothaus; H. Päs; A. Y. Smirnov

    2000-10-08

    The relations between the effective Majorana mass of the electron neutrino, $m_{ee}$, responsible for neutrinoless double beta decay, and the neutrino oscillation parameters are considered. We show that for any specific oscillation pattern $m_{ee}$ can take any value (from zero to the existing upper bound) for normal mass hierarchy and it can have a minimum for inverse hierarchy. This means that oscillation experiments cannot fix in general $m_{ee}$. Mass ranges for $m_{ee}$ can be predicted in terms of oscillation parameters with additional assumptions about the level of degeneracy and the type of hierarchy of the neutrino mass spectrum. These predictions for $m_{ee}$ are systematically studied in the specific schemes of neutrino mass and flavor which explain the solar and atmospheric neutrino data. The contributions from individual mass eigenstates in terms of oscillation parameters have been quantified. We study the dependence of $m_{ee}$ on the non-oscillation parameters: the overall scale of the neutrino mass and the relative mass phases. We analyze how forthcoming oscillation experiments will improve the predictions for $m_{ee}$. On the basis of these studies we evaluate the discovery potential of future \\znbb decay searches. The role \\znbb decay searches will play in the reconstruction of the neutrino mass spectrum is clarified. The key scales of $m_{ee}$, which will lead to the discrimination among various schemes are: $m_{ee} \\sim 0.1$ eV and $m_{ee} \\sim 0.005$ eV.

  15. Measurable neutrino mass scale in A{sub 4}xSU(5)

    SciTech Connect

    Antusch, S.; Spinrath, M. [Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, D-80805 Muenchen (Germany); King, Stephen F. [School of Physics and Astronomy, University of Southampton, SO17 1BJ Southampton (United Kingdom)

    2011-01-01

    We propose a supersymmetric A{sub 4}xSU(5) model of quasidegenerate neutrinos which predicts the effective neutrino mass m{sub ee} relevant for neutrinoless double beta decay to be proportional to the neutrino mass scale, thereby allowing its determination approximately independently of unknown Majorana phases. Such a natural quasidegeneracy is achieved by using A{sub 4} family symmetry (as an example of a non-Abelian family symmetry with real triplet representations) to enforce a contribution to the neutrino mass matrix proportional to the identity. Tribimaximal neutrino mixing as well as quark CP violation with {alpha}{approx_equal}90 deg. d a leptonic CP phase {delta}{sub MNS{approx_equal}}90 deg. arise from the breaking of the A{sub 4} family symmetry by the vacuum expectation values of four 'flavon' fields pointing in specific postulated directions in flavor space.

  16. Current MINOS Neutrino Oscillation Results

    SciTech Connect

    Habig, Alec; /Minnesota U., Duluth

    2009-07-01

    The MINOS experiment is now making precise measurements of the {nu}{sub {mu}} disappearance oscillations seen in atmospheric neutrinos, tests possible disappearance to sterile {nu} by measuring the neutral current flux, and has extended our reach towards the so far unseen {theta}{sub 13} by looking for {nu}{sub e} appearance in the {nu}{sub {mu}} beam. It does so by using the intense, well-understood NuMI neutrino beam created at Fermilab and observing it 735km away at the Soudan Mine in Northeast Minnesota. High-statistics studies of the neutrino interactions themselves and the cosmic rays seen by the MINOS detectors have also been made. Results from MINOS first three years of operations will be presented.

  17. Stimulated neutrino transformation through turbulence

    NASA Astrophysics Data System (ADS)

    Patton, Kelly M.; Kneller, James P.; McLaughlin, Gail C.

    2014-04-01

    We derive an analytical solution for the flavor evolution of a neutrino through a turbulent density profile which is found to accurately predict the amplitude and transition wavelength of numerical solutions on a case-by-case basis. The evolution is seen to strongly depend upon those Fourier modes in the turbulence which are approximately the same as the splitting between neutrino eigenvalues. Transitions are strongly enhanced by those Fourier modes in the turbulence which are approximately the same as the splitting between neutrino eigenvalues. We also find a suppression of transitions due to the long wavelength modes when the ratio of their amplitude and the wave number is of order, or greater than, the first root of the Bessel function J0.

  18. Model of neutrino effective masses

    SciTech Connect

    Dinh Nguyen Dinh; Nguyen Thi Hong Van [Institute of Physics and Electronics, VAST, 10 Dao-Tan, Hanoi (Viet Nam); Abdus Salam International Centre for Theoretical Physics, Strada Costiera 11, I-34014 Trieste (Italy); Nguyen Anh Ky [Institute of Physics and Electronics, VAST, 10 Dao-Tan, Hanoi (Viet Nam); Abdus Salam International Centre for Theoretical Physics, Strada Costiera 11, I-34014 Trieste (Italy); LAPTH, 9 Chemin de Bellevue, B.P. 110, F-74941 Annecy-le-Vieux Cedex France (France); Theory Devision, CERN, CH-1211 Geneva 23 (Switzerland); Phi Quang Van [Institute of Physics and Electronics, VAST, 10 Dao-Tan, Hanoi (Viet Nam)

    2006-10-01

    It is shown that an effective (nonrenormalizable) coupling of lepton multiplets to scalar triplets in the 331 model with sterile/exotic neutrinos, can be a good way for generating neutrino masses of different types. The method is simple and avoids radiative/loop calculations which, sometimes, are long and complicated. Basing on some astrophysical arguments it is also stated that the scale of SU(3){sub L} symmetry breaking is at TeV scale, in agreement with earlier investigations. Or equivalently, starting from this symmetry breaking scale we could have sterile/exotic neutrinos with mass of a few keV's which could be used to explain several astrophysical and cosmological puzzles, such as the dark matter, the fast motion of the observed pulsars, the re-ionization of the Universe, etc.

  19. The Unruh effect and oscillating neutrinos

    E-print Network

    Ahluwalia, Dharam Vir; Torrieri, Giorgio

    2015-01-01

    We point out that neutrino oscillations imply an ambiguity in the definition of the vacuum and the coupling to gravity, with experimentally observable consequences due to the Unruh effect. In an accelerating frame, the detector should see a bath of mass Eigenstates neutrinos. In inertial processes, neutrinos are produced and absorbed as charge Eigenstates. The two cannot be reconciled by a spacetime coordinate transformation. This makes manifestations of the Unruh effect in neutrino physics a promising probe of both neutrinos and fundamental quantum field theory. In this respect, we suggest $p\\rightarrow n +\\ell^+ + {\

  20. The Unruh effect and oscillating neutrinos

    E-print Network

    Dharam Vir Ahluwalia; Lance Labun; Giorgio Torrieri

    2015-05-15

    We point out that neutrino oscillations imply an ambiguity in the definition of the vacuum and the coupling to gravity, with experimentally observable consequences due to the Unruh effect. In an accelerating frame, the detector should see a bath of mass Eigenstates neutrinos. In inertial processes, neutrinos are produced and absorbed as charge Eigenstates. The two cannot be reconciled by a spacetime coordinate transformation. This makes manifestations of the Unruh effect in neutrino physics a promising probe of both neutrinos and fundamental quantum field theory. In this respect, we suggest $p\\rightarrow n +\\ell^+ + {\

  1. Investigating CPT Conservation in Sterile Neutrino Fits

    NASA Astrophysics Data System (ADS)

    Ignarra, Christina

    2010-02-01

    We investigate compatibility between neutrino and antineutrino short-baseline oscillation experiments under a two-neutrino oscillation hypothesis due to a sterile neutrino at ?m^2˜1 eV^2. We explore the preliminary MINOS antineutrino disappearance results as well as antineutrino oscillation results from LSND, MiniBooNE, KARMEN, Bugey, and Chooz, and neutrino oscillation results from NOMAD, MiniBooNE, CCFR84, and CDHS. We find that a combined fit of the antineutrino data yields a high chi-squared probability, while the global fit including neutrino and antineutrino data yields high incompatibility. CPT-violating fits within this scenario are also explored. )

  2. New astrophysical limit on neutrino millicharge

    E-print Network

    Alexander I. Studenikin; Ilya V. Tokarev

    2014-11-09

    An impact of a nonzero neutrino millicharge in astrophysics is tested. It is shown that in astrophysical environments electromagnetic interactions of the neutrino millicharge with strong electromagnetic fields as well as weak interactions of the neutrinos with dense background matter can produce new phenomena accessible for astrophysical observations. On this basis a new limit on the neutrino millicharge $q_0<1.3\\times10^{-19}e_0$ is obtained. This limit is among the strongest astrophysical constraint on the neutrino millicharge. Some other possible applications of the obtained results to astrophysics are discussed in details.

  3. Search for neutrino bursts from collapsing stars

    SciTech Connect

    Deakyne, M.S.

    1981-01-01

    Various scenarios of collapsing stars are reviewed with emphasis placed on the experimental aspects necessary for these objects to be detected. A search, covering two years of data, collected by the neutrino telescope, located in the Homestake Gold Mine, South Dakota, is presented. The detector, located at a depth of 4200 meters-water-equivalent has a sensitivity sufficiently high to detect 10 MeV neutrinos and anti-neutrinos from collapsing stars which release 10/sup 53/ ergs of neutrino energy at a distance of the galactic center. No neutrino bursts have been seen over the running time of 384 days.

  4. On solar neutrino fluxes in radiochemical experiments

    E-print Network

    R. N. Ikhsanov; Yu. N. Gnedin; E. V. Miletsky

    2005-12-08

    We analyze fluctuations of the solar neutrino flux using data from the Homestake, GALLEX, GNO, SAGE and Super Kamiokande experiments. Spectral analysis and direct quantitative estimations show that the most stable variation of the solar neutrino flux is a quasi-five-year periodicity. The revised values of the mean solar neutrino flux are presented in Table 4. They were used to estimate the observed pp-flux of the solar electron neutrinos near the Earth. We consider two alternative explanations for the origin of a variable component of the solar neutrino deficit.

  5. Non-Zero Electric Charge of the Neutrino and the Solar Neutrino Problem

    E-print Network

    A. Yu. Ignatiev; G. C. Joshi

    1994-07-21

    It has recently been shown that the neutrino can have non-zero electric charge in a number of gauge theories, including the Minimal Standard Model. Assuming non-zero neutrino charge, we develop a new approach to the solar neutrino problem. The key idea is that the charged neutrinos will be deflected by the Lorentz force while they are crossing the solar magnetic fields. Such a deflection will result in the anisotropy of the solar neutrino flux. Because of this anisotropy, the solar neutrino flux registered on earth can be reduced as compared to the Standard Solar Model prediction. The mechanism is purely classical and does not require neutrino oscillations, spin-flip or neutrino decay. We discuss qualitatively the consequences of our scenario for present and future solar neutrino experiments as well as differences between our mechanism and other proposed solutions.

  6. Neutrino Factory Near Detector Simulation

    SciTech Connect

    Karadzhov, Yordan [Department of Atomic Physics, St. Kliment Ohridski University of Sofia, Sofia (Bulgaria)

    2010-03-30

    We present a simulation with GENIE MC generator of the Neutrino Factory baseline near detector interaction rates for the purely leptonic process nu{sub m}u+e{sup -}->nu{sub e}+mu{sup -} and for nu{sub m}u+N->mu{sup -}+X scattering in view of measuring the first one and suppressing the second one for neutrino flux estimation. A set of most sensitive measurable quantities are discussed and their selective power against experimental uncertainties is examined.

  7. Neutrino radiation hazards: A paper tiger

    SciTech Connect

    Cossairt, J.D.; Grossman, N.L.; Marshall, E.T.

    1996-09-01

    Neutrinos are present in the natural environment due to terrestrial, solar, and cosmic sources and are also produced at accelerators both incidentally and intentionally as part of physics research programs. Progress in fundamental physics research has led to the creation of beams of neutrinos of ever-increasing intensity and/or energy. The large size and cost associated with these beams attracts, and indeed requires, public interest, support, and some understanding of the `exotic` particles produced, including the neutrinos. Furthermore, the very word neutrino (`little neutral one`, as coined by Enrico Fermi) can lead to public concern due to confusion with `neutron`, a word widely associated with radiological hazards. Adding to such possible concerns is a recent assertion, widely publicized, that neutrinos from astronomical events may have led to the extinction of some biological species. Presented here are methods for conservatively estimating the dose equivalent due to neutrinos as well as an assessment of the possible role of neutrinos in biological extinction processes. It is found that neutrinos produced by the sun and modern particle accelerators produce inconsequential dose equivalent rates. Examining recent calculations concerning neutrinos incident upon the earth due to stellar collapse, it is concluded that it is highly unlikely that these neutrinos caused the mass extinctions of species found in the paleontological record. Neutrino radiation hazards are, then, truly a `paper tiger`. 14 refs., 1 fig., 1 tab.

  8. A cosmological bound on radiative neutrino lifetime

    NASA Astrophysics Data System (ADS)

    Mirizzi, A.; Montanino, D.; Serpico, P. D.

    2008-07-01

    Neutrino oscillation experiments and direct bounds on absolute masses constrain neutrino mass differences to fall into the microwave energy range, for most of the allowed parameter space. As a consequence of these recent phenomenological advances, older constraints on radiative neutrino decays based on diffuse background radiations and assuming strongly hierarchical masses in the eV range are now outdated. We thus derive new bounds on the radiative neutrino lifetime using the high precision cosmic microwave background spectral data collected by the FIRAS instrument on board of COBE. The lower bound on neutrino lifetime is between a few ×1019 s and ~ 5 × 1020 s, depending on the neutrino mass ordering and on the absolute neutrino mass scale. However, due to phase space limitations, the upper bound on the effective magnetic moment mediating the decay is not better than ~10-8 ?B. We also comment about possible improvements of these limits, by means of recent diffuse infrared photon background data.

  9. Collective neutrino oscillations and spontaneous symmetry breaking

    E-print Network

    Duan, Huaiyu

    2015-01-01

    Neutrino oscillations in a hot and dense astrophysical environment such as a core-collapse supernova pose a challenging, seven-dimensional flavor transport problem. To make the problem even more difficult (and interesting), neutrinos can experience collective oscillations through nonlinear refraction in the dense neutrino medium in this environment. Significant progress has been made in the last decade towards the understanding of collective neutrino oscillations in various simplified neutrino gas models with imposed symmetries and reduced dimensions. However, a series of recent studies seem to have "reset" this progress by showing that these models may not be compatible with collective neutrino oscillations because the latter can break the symmetries spontaneously if they are not imposed. We review some of the key concepts of collective neutrino oscillations by using a few simple toy models. We also elucidate the breaking of spatial and directional symmetries in these models because of collective oscillation...

  10. Probing Neutrino Hierarchy and Chirality via Wakes

    E-print Network

    Hong-Ming Zhu; Ue-Li Pen; Xuelei Chen; Derek Inman

    2014-12-04

    The relic neutrinos are expected to acquire a bulk relative velocity with respect to the dark matter at low redshifts, and downstream of dark matter halos neutrino wakes are expected to develop. We propose a method of measuring the neutrino mass based on this mechanism. The neutrino wake will cause a dipole distortion of the galaxy-galaxy lensing pattern. This effect could be detected by combining upcoming lensing surveys, e.g. the LSST and Euclid surveys with a low redshift galaxy survey or a 21cm intensity mapping survey which can map the neutrino flow field. The data obtained with LSST and Euclid should enable us to make positive detection if the three neutrino masses are Quasi-Degenerate, and a future high precision 21cm lensing survey would allow the normal hierarchy and inverted hierarchy cases to be distinguished, and even the right handed Dirac neutrinos may be detectable.

  11. Review of Reactor Neutrino Oscillation Experiments

    E-print Network

    C. Mariani

    2012-02-05

    In this document we will review the current status of reactor neutrino oscillation experiments and present their physics potentials for measuring the $\\theta_{13}$ neutrino mixing angle. The neutrino mixing angle $\\theta_{13}$ is currently a high-priority topic in the field of neutrino physics. There are currently three different reactor neutrino experiments, \\textsc{Double Chooz}, \\textsc{Daya Bay} and \\textsc{Reno} and a few accelerator neutrino experiments searching for neutrino oscillations induced by this angle. A description of the reactor experiments searching for a non-zero value of $\\theta_{13}$ is given, along with a discussion of the sensitivities that these experiments can reach in the near future.

  12. PREFACE: 1st Franco–Algerian Workshop on Neutrino Physics

    NASA Astrophysics Data System (ADS)

    Mebarki, N.; Mimouni, J.; Vanucci, F.; Aissaoui, H.

    2015-04-01

    The first Franco–Algerian workshop on neutrino physics was held on 22-23 October 2013 at the University of Mentouri, Constantine, Algeria. It was jointly organized by the Laboratory of Mathematical and Subatomic Physics (LPMS) and the Direction of Scientific Research (DGRSTD) for the Algerian side, and for the French part by the IN2P3, CNRS and CEA IRFU. It is one of a series of international scientific meetings organized every two years by the LPMS at Constantine on high energy physics (theoretical, nuclear physics, classical and quantum cosmology, astrophysics, mathematical physics and quantum computing etc...) to maintain a high quality in scientific research and education at Algerian universities. This specific meeting brought together experts in particle physics, astrophysics and cosmology from France and Algeria. It touched upon several theoretical, phenomenological as well as experimental aspects of the neutrinos. The workshop participants were mostly young researchers from many universities and research institutes in Algeria. The physics of neutrinos is a very active field in particle physics, hence the importance for the High Energy community in Algeria to gain expertise in this ''strategic'' area at the intersection of various topics in theoretical physics and high energy astrophysics (SM physics, CP violation, in general, SNe explosions, baryogenesis...). The neutrino proposed by Pauli back in 1930 as a ''desperate remedy'' to save the law of energy conservation in beta decay had a bright early history. Discovered in 1956 in the Cowan–Reines experiment despite all odds, this elusive particle which enabled us to understand the chiral nature of the weak interactions which later lead to the electro-weak unification finally appears to hold a key role in understanding subatomic physics as well as the structure and structuration of the Universe. It is also, after the discovery of the Higgs particle at the LHC in 2012, the only grey area left today in the Standard Model of particle physics. The various contributions covered in this scientific meeting lie between oral and posters presentations including many specialized topics like neutrinos' oscillations, the various large experiments like Borexino and Opera, the geo-neutrinos, as more theoretical topics like Majorana neutrinos and the double beta decay, anomalies in neutrino physics, neutrino models beyond the standard model and in curved space-time. We hope that putting in print the various contributions to this exciting meeting will be a valuable contribution to the literature to both professional as well as young researchers in neutrino physics. This workshop couldn't have taken place without the generous and unfaltering support of the DGRSTD which fully financed it through its various stages. Editors Profs. The editors: Mebarki N., Mimouni J., Vanucci F., Aissaoui H.

  13. Solar (and other) Neutrinos 4.1 Solar neutrino detectors

    E-print Network

    Washington at Seattle, University of - Department of Physics, Electroweak Interaction Research Group

    experiments had provided data, the Homestake 37 Cl experi- ment, the gallium experiments SAGE and GALLEXKamiokande record neutrino-electron elastic scattering event-by-event. The Homestake Experiment Detection determining the central temperature of the sun. The experiment was mounted in the Homestake Gold Mine, Lead

  14. Neutrino tomography - Learning about the Earth's interior using the propagation of neutrinos

    E-print Network

    Walter Winter

    2006-07-03

    Because the propagation of neutrinos is affected by the presence of Earth matter, it opens new possibilities to probe the Earth's interior. Different approaches range from techniques based upon the interaction of high energy (above TeV) neutrinos with Earth matter, to methods using the MSW effect on the neutrino oscillations of low energy (MeV to GeV) neutrinos. In principle, neutrinos from many different sources (sun, atmosphere, supernovae, beams etc.) can be used. In this talk, we summarize and compare different approaches with an emphasis on more recent developments. In addition, we point out other geophysical aspects relevant for neutrino oscillations.

  15. Cosmic rays & Neutrinos Historical development

    E-print Network

    Gaisser, Thomas K.

    | Perm in hairdressing Deutsch The Neutrino Wolfgang Pauli's name is inseparable from his pioneering. The starting point for Pauli was the continuous energy spectrum of beta rays, which could not be interpreted conservation, which Pauli could not accept because the principle of the conservation of energy had proved

  16. Exploring the Ultrahigh Energy Neutrino Universe

    E-print Network

    D. B. Cline; F. W. Stecker

    2000-03-30

    Astronomy at the highest energies observed must be performed by studying neutrinos rather than photons because the universe is opaque to photons of these energies. By making observations of neutrinos with energies above 10 EeV one can deduce information about the distribution and cosmological history of cosmic rays which may have been accelerated to energies above 100 EeV. Very large fluxes of neutrinos at these energies which exhibit a hard spectrum would be evidence of a GUT phase transition or superheavy dark matter particles. Neutrinos at energies around a PeV may be produced in observable quantities in active galaxies from the acceleration and interactions of cosmic rays in the vicinity of massive black holes or in relativistic jets produced by these black holes. Cosmological gamma-ray bursts may also produce PeV neutrinos. Neutrinos at these energies may oscillate into tau neutrinos which can travel through the Earth by the process of regeneration and produce upward moving air-showers. Neutrinos of energies above of 1000 EeV can produce ultrahigh energy cosmic rays thorugh interactions with big-bang neutrinos, producing Z bosons. This "Z-burst" phenomenon can be used to study the mass and distribution of big-bang neutrinos.

  17. Status of global fits to neutrino oscillations

    NASA Astrophysics Data System (ADS)

    Maltoni, Michele; Schwetz, Thomas; Tórtola, Mariam; Valle, José W. F.

    2004-09-01

    We review the present status of global analyses of neutrino oscillations, taking into account the most recent neutrino data including the latest KamLAND and K2K updates presented at Neutrino 2004, as well as state-of-the-art solar and atmospheric neutrino flux calculations. We give the two-neutrino solar + KamLAND results, and the two-neutrino atmospheric + K2K oscillation regions, discussing in each case the robustness of the oscillation interpretation against departures from the Standard Solar Model and the possible existence of non-standard neutrino physics. Furthermore, we give the best-fit values and allowed ranges of the three-flavour oscillation parameters from the current worlds' global neutrino data sample and discuss in detail the status of the small parameters agr equiv DgrmSOL2/DgrmATM2 as well as sin2 thgr13, which characterize the strength of CP violating effects in neutrino oscillations. We also update the degree of rejection of four-neutrino interpretations of the LSND evidence in view of the most recent developments.

  18. Beta Beams for Neutrino Production

    SciTech Connect

    Wildner, Elena [CERN, Geneva (Switzerland)

    2010-03-30

    This paper gives an overview of the work done so far to produce sufficient neutrino fluxes for neutrino oscillation physics using beta beams. The design study on a beta beam scenario, the EURISOL (European Isotope Separation On-Line Radioactive Ion Beam Facility) Design Study, a project funded by the European Commission (EC), is now ready to be published. The study is based on the acceleration of {sup 6}He and {sup 18}Ne ions to produce the (anti-)neutrino beam using the existing CERN infrastructure for acceleration of the ions. We will here briefly describe the work with emphasis on how potential showstoppers, in particular radiation safety and equipment damage, have been dealt with. New results for the production of {sup 6}He show very encouraging results. We are now confident that this ion is a good choice to produce antineutrinos. However, the ion production needed for the physics experiments could not, up to now, be reasonably satisfied for {sup 18}Ne. Therefore, studies of alternative beta emitters, {sup 8}Li and {sup 8}B, with properties interesting for physics reach, have been proposed. The production of these ions is studied within the EC funded EUROnu project, ''A High Intensity Neutrino Oscillation Facility for Europe.'' This project will end in 2012. A small storage ring, in which the beam traverses a target, creating the {sup 8}Li and {sup 8}B isotopes that will be collected and accelerated, is studied in this proposal. We present the latest developments for the production of these ions, including a production ring lattice. Extensive Geant4 simulations have been done with the aim of developing a model of the production target that can be used for simulations of the necessary cooling system. In this paper we present the status of the work performed and an overview of ongoing and planned activities to make the beta beam project a solid proposal for neutrino production within the EUROnu project.

  19. Neutrino-2008: Where are we? Where are we going?

    NASA Astrophysics Data System (ADS)

    Smirnov, Alexei Yu

    2008-11-01

    Our present knowledge of neutrinos can be summarized in terms of the 'standard neutrino scenario'. Phenomenology of this scenario as well as attempts to uncover physics behind neutrino mass and mixing are described. Goals of future studies include complete reconstruction of the neutrino mass and flavor spectrum, further test of the standard scenario and search for new physics beyond it. Developments of new experimental techniques may lead to construction of new neutrino detectors from table-top to multi-Megaton scales which will open new horizons in the field. With detection of neutrino bursts from the Galactic supernova and high energy cosmic neutrinos neutrino astrophysics will enter qualitatively new phase. Neutrinos and LHC (and future colliders), neutrino astronomy, neutrino structure of the Universe, and probably, neutrino technologies will be among leading topics of research.

  20. Solar neutrino physics with low-threshold dark matter detectors

    E-print Network

    Strigari, L.?E.

    Dark matter detectors will soon be sensitive to Solar neutrinos via two distinct channels: coherent neutrino-nucleus and neutrino-electron elastic scatterings. We establish an analysis method for extracting Solar model ...