WorldWideScience

Sample records for electron neutrino oscillations

  1. Neutrino oscillations and neutrino-electron scattering

    International Nuclear Information System (INIS)

    Kayser, B.; Rosen, S.P.

    1980-10-01

    Neutrino flavor oscillations can significantly alter the cross section for neutrino-electron scattering. As a result, such oscillations can affect the comparison between existing reactor data and theories of neutral-current processes. They may also lead to strikingly large effects in high-energy accelerator experiments

  2. A search for oscillations of muon-neutrinos to electron-neutrinos

    CERN Document Server

    Procario, Michael

    1986-01-01

    The author has searched in the heavy liquid bubble chamber BEBC for electron neutrino charge current events which could arise from oscillation of the muon neutrinos (average energy ∼1.5 GeV) obtained with a low energy proton beam at the CERN PS targeted 825 m upstream from BEBC. The appearance of electron neutrino CC interactions provides a sensitive indication of nu/sub μ/ → nu/sub e/ oscillation. The author observed 460 muon neutrino CC events and 4 electron neutrino CC events with an estimated background of 3.5 electron neutrino CC events. Using the likelihood ratio method to test the oscillation hypothesis, the author finds no evidence for nu/sub μ/ → nu/sub e/ oscillation and set the limits δm2 ≤ 0.13 eV2 (maximal mixing) and sin22theta ≤ 0.018 for δm2 = 3 eV2 at 90% confidence level

  3. Neutrino oscillation study in the muon neutrinoelectron neutrino channel at the Brookhaven accelerator

    International Nuclear Information System (INIS)

    Astier, P.

    1987-09-01

    The E816 experiment described in this thesis is devoted to a neutrino oscillation search at the Brookhaven AGS. The method used here is to look with a fine grained calorimeter for the appearence of electron neutrino in a muon neutrino beam. After recalling the theoretical treatment of the neutrino mass problem, the experimental phenomenology of massive neutrinos and more specifically neutrino oscillations is reviewed. The experiment itself is then extensively described, both on the technical side (detector, beam, simulation) and on the analysis side. In particular the statistical separation of the electromagnetic showers from electrons - our signal - and from photons - our background - treated in detail. The present analysis is based on 2/3 of the final statistics and it leads to the - preliminary - observation of an electron excess in the neutrino interactions yielding 19 ± 15.6 (stat) ± 7 (syst) [fr

  4. Observing Muon Neutrino to Electron Neutrino Oscillations in the NOνA Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Xin, Tian [Iowa State U.

    2016-01-01

    Neutrino oscillations offers an insight on new physics beyond the Standard Model. The three mixing angles (θ12, θ13 and θ23) and the two mass splittings (Δm2 and Αm2 ) have been measured by different neutrino oscillation experiments. Some other parameters including the mass ordering of different neutrino mass eigenstates and the CP violation phase are still unknown. NOνA is a long-baseline accelerator neutrino experiment, using neutrinos from the NuMI beam at Fermilab. The experiment is equipped with two functionally identical detectors about 810 kilometers apart and 14 mrad off the beam axis. In this configuration, the muon neutrinos from the NuMI beam reach the disappearance maximum in the far detector and a small fraction of that oscillates into electron neutrinos. The sensitivity to the mass ordering and CP viola- tion phase determination is greately enhanced. This thesis presents the νeappearance analysis using the neutrino data collected with the NOνA experiment between February 2014 and May 2015, which corresponds to 3.45 ×1020 protons-on-target (POT). The νe appearance analysis is performed by comparing the observed νe CC-like events to the estimated background at the far detector. The total background is predicted to be 0.95 events with 0.89 originated from beam events and 0.06 from cosmic ray events. The beam background is obtained by extrapolating near detector data through different oscillation channels, while the cosmic ray background is calculated based on out-of-time NuMI trigger data. A total of 6 electron neutrino candidates are observed in the end at the far detector which represents 3.3 σ excess over the predicted background. The NOνA result disfavors inverted mass hierarchy for δcp ϵ [0, 0.6π] at 90% C.L.

  5. Impact of Neutrino Flavor Oscillations on the Neutrino-driven Wind Nucleosynthesis of an Electron-capture Supernova

    Science.gov (United States)

    Pllumbi, Else; Tamborra, Irene; Wanajo, Shinya; Janka, Hans-Thomas; Hüdepohl, Lorenz

    2015-08-01

    Neutrino oscillations, especially to light sterile states, can affect nucleosynthesis yields because of their possible feedback effect on the electron fraction (Ye). For the first time, we perform nucleosynthesis calculations for neutrino-driven wind trajectories from the neutrino-cooling phase of an 8.8 {M}⊙ electron-capture supernova (SN), whose hydrodynamic evolution was computed in spherical symmetry with sophisticated neutrino transport and whose Ye evolution was post-processed by including neutrino oscillations between both active and active-sterile flavors. We also take into account the α-effect as well as weak magnetism and recoil corrections in the neutrino absorption and emission processes. We observe effects on the Ye evolution that depend in a subtle way on the relative radial positions of the sterile Mikheyev-Smirnov-Wolfenstein resonances, on collective flavor transformations, and on the formation of α particles. For the adopted SN progenitor, we find that neutrino oscillations, also to a sterile state with eV mass, do not significantly affect the element formation and in particular cannot make the post-explosion wind outflow neutron-rich enough to activate a strong r-process. Our conclusions become even more robust when, in order to mimic equation-of-state-dependent corrections due to nucleon potential effects in the dense-medium neutrino opacities, six cases with reduced Ye in the wind are considered. In these cases, despite the conversion of active neutrinos to sterile neutrinos, Ye increases or is not significantly lowered compared to the values obtained without oscillations and active flavor transformations. This is a consequence of a complicated interplay between sterile-neutrino production, neutrino-neutrino interactions, and α-effect.

  6. Neutrino oscillations in the early universe

    International Nuclear Information System (INIS)

    Enqvist, K.

    1990-01-01

    The oscillations of electron neutrinos into inert neutrinos may have resonant behaviour in the heat bath of the early Universe. It is shown that any initial neutrino asymmetry will be washed away by the oscillations. Neutrino oscillations would affect also primordial helium production, which implies stringent limits on the neutrino mixing parameters. (orig.)

  7. J-PARC Press Release: Electron neutrino oscillation detected at T2K

    CERN Multimedia

    T2K Press Office

    2011-01-01

    Tsukuba, Japan, June 15, 2011. The T2K experiment, whose primary purpose is to study neutrino interactions at a large distance from their source, has detected 6 electron neutrino candidate events based on the data collected before March 11, 2011. For the first time, it was possible to observe an indication that muon neutrinos are able to transform into electron neutrinos over a distance of 295 km through the quantum mechanical phenomena of neutrino flavor oscillations.   The Super-Kamiokande detector, in Japan. © 2011, High Energy Accelerator Research Organization, KEK. The T2K experiment is searching for the neutrino oscillation phenomena, where particular types of neutrinos transform into other types of neutrinos. These observations help determine neutrino masses, as well elucidating the uncharted nature of neutrinos, such as the relationship among three neutrino generations (types). T2K aims at the world’s best sensitivity by detecting neutrinos with the Super-Kamiokande d...

  8. Impact of neutrino flavor oscillations on the neutrino-driven wind nucleosynthesis of an electron-capture supernova

    NARCIS (Netherlands)

    Pllumbi, E.; Tamborra, I.; Wanajo, S.; Janka, H.-T.; Hüdepohl, L.

    2015-01-01

    Neutrino oscillations, especially to light sterile states, can affect nucleosynthesis yields because of their possible feedback effect on the electron fraction (Ye). For the first time, we perform nucleosynthesis calculations for neutrino-driven wind trajectories from the neutrino-cooling phase of

  9. Exploring new features of neutrino oscillations with very low energy monoenergetic neutrinos

    CERN Document Server

    Vergados, J D

    2010-01-01

    In the present work we propose to study neutrino oscillations employing sources of monoenergetic neutrinos following electron capture by the nucleus. Since the neutrino energy is very low the smaller of the two oscillation lengths, L23, appearing in this electronic neutrino disappearance experiment can be so small that the full oscillation can take place inside the detector and one may determine very accurately the neutrino oscillation parameters. Since in this case the oscillation probability is proportional to theta13, one can measure or set a better limit on the unknown parameter theta13. This is quite important, since, if this mixing angle vanishes, there is not going to be CP violation in the leptonic sector. The best way to detect it is by measuring electron recoils in neutrino-electron scattering. 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 energ...

  10. Neutrino wave function and oscillation suppression

    International Nuclear Information System (INIS)

    Dolgov, A.D.; Lychkovskiy, O.V.; Mamonov, A.A.; Okun, L.B.; Schepkin, M.G.

    2005-01-01

    We consider a thought experiment, in which a neutrino is produced by an electron on a nucleus in a crystal. The wave function of the oscillating neutrino is calculated assuming that the electron is described by a wave packet. If the electron is relativistic and the spatial size of its wave packet is much larger than the size of the crystal cell, then the wave packet of the produced neutrino has essentially the same size as the wave packet of the electron. We investigate the suppression of neutrino oscillations at large distances caused by two mechanisms: (1) spatial separation of wave packets corresponding to different neutrino masses; (2) neutrino energy dispersion for given neutrino mass eigenstates. We resolve the contributions of these two mechanisms. (orig.)

  11. Neutrino oscillations in dense neutrino gases

    International Nuclear Information System (INIS)

    Samuel, S.

    1993-01-01

    We consider oscillations of neutrinos under conditions in which the neutrino density is sufficiently large that neutrino-neutrino interactions cannot be neglected. A formalism is developed to treat this highly nonlinear system. Numerical analysis reveals a rich array of phenomena. In certain gases, a self-induced Mikheyev-Smirnov-Wolfenstein effect occurs in which electron neutrinos are resonantly converted into muon neutrinos. In another relatively low-density gas, an unexpected parametric resonant conversion takes place. Finally, neutrino-neutrino interactions maintain coherence in one system for which a priori one expected decoherence

  12. Measuring $\\theta_{13}$ via Muon Neutrino to Electron Neutrino Oscillations in the MINOS Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Toner, Ruth B. [Univ. of Cambridge (United Kingdom). Pembroke College

    2011-01-01

    One of the primary goals in neutrino physics at the present moment is to make a measurement of the neutrino oscillation parameter $\\theta_{13}$. This parameter, in addition to being unknown, could potentially allow for the introduction of CP violation into the lepton sector. The MINOS long-baseline neutrino oscillation experiment has the ability to make a measurement of this parameter, by looking for the oscillation of muon neutrinos to electron neutrinos between a Near and Far Detector over a distance of 735 km. This thesis discusses the development of an analysis framework to search for this oscillation mode. Two major improvements to pre-existing analysis techniques have been implemented by the author. First, a novel particle ID technique based on strip topology, known as the Library Event Matching (LEM) method, is optimized for use in MINOS. Second, a multiple bin likelihood method is developed to fit the data. These two improvements, when combined, increase MINOS' sensitivity to $\\sin^2(2\\theta_{13})$ by 27\\% over previous analyses. This thesis sees a small excess over background in the Far Detector. A Frequentist interpretation of the data rules out $\\theta_{13}=0$ at 91\\%. A Bayesian interpretation of the data is also presented, placing the most stringent upper boundary on the oscillation parameter to date, at $\\sin^2(2\\theta_{13})<0.09(0.015)$ for the Normal (Inverted) Hierarchy and $\\delta_{CP}=0$.

  13. New neutrino oscillation results from NOVA

    CERN Multimedia

    CERN. Geneva

    2018-01-01

    Neutrinos oscillate among flavors as they travel because a neutrino of a particular flavor is also a superposition of multiple neutrinos with slightly different masses.  The interferometric nature of oscillations allows these tiny mass differences to be measured, along with the parameters of the PMNS matrix which governs the mixing. However, since neutrinos only interact weakly, a powerful neutrino source and massive detectors are required to measure them. In this talk I will show recently updated results from NOvA, a long-baseline neutrino oscillation experiment at Fermilab with two functionally identical scintillator detectors. I will present measurements of muon neutrino disappearance and electron neutrino appearance, and what constraints those measurements put on the remaining open questions in neutrino oscillations: Is the neutrino mass hierarchy "normal" or "inverted?" Do neutrino oscillations violate CP symmetry? Is the mixing in the atmospheric sector maximal? The recent update includes 50%...

  14. Influence of flavor oscillations on neutrino beam instabilities

    Energy Technology Data Exchange (ETDEWEB)

    Mendonça, J. T., E-mail: titomend@ist.utl.pt [Instituto de Física, Universidade de São Paulo, 05508-090 São Paulo SP (Brazil); Haas, F. [Instituto de Física, Universidade Federal do Rio Grande do Sul, 91501-970 Porto Alegre RS (Brazil); Bret, A. [ETSI Industriales, Universidad de Castilla-La Mancha, 13071 Ciudad Real, Spain and Instituto de Investigaciones Energeticas y Aplicaciones Industriales, Campus Universitario de Ciudad Real, 13071 Ciudad Real (Spain)

    2014-09-15

    We consider the collective neutrino plasma interactions and study the electron plasma instabilities produced by a nearly mono-energetic neutrino beam in a plasma. We describe the mutual interaction between neutrino flavor oscillations and electron plasma waves. We show that the neutrino flavor oscillations are not only perturbed by electron plasmas waves but also contribute to the dispersion relation and the growth rates of neutrino beam instabilities.

  15. A study of muon neutrino to electron neutrino oscillations in the MINOS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Tingjun [Stanford Univ., CA (United States)

    2009-03-01

    The observation of neutrino oscillations (neutrino changing from one flavor to another) has provided compelling evidence that the neutrinos have non-zero masses and that leptons mix, which is not part of the original Standard Model of particle physics. The theoretical framework that describes neutrino oscillation involves two mass scales (Δmatm2 and Δmsol2), three mixing angles (θ12, θ23, and θ13) and one CP violating phase (δCP). Both mass scales and two of the mixing angles (θ12 and θ23) have been measured by many neutrino experiments. The mixing angle θ13, which is believed to be very small, remains unknown. The current best limit on θ13 comes from the CHOOZ experiment: θ13 < 11° at 90% C.L. at the atmospheric mass scale. δCP is also unknown today. MINOS, the Main Injector Neutrino Oscillation Search, is a long baseline neutrino experiment based at Fermi National Accelerator Laboratory. The experiment uses a muon neutrino beam, which is measured 1 km downstream from its origin in the Near Detector at Fermilab and then 735 km later in the Far Detector at the Soudan mine. By comparing these two measurements, MINOS can obtain parameters in the atmospheric sector of neutrino oscillations. MINOS has published results on the precise measurement of Δmatm2 and θ23 through the disappearance of muon neutrinos in the Far Detector and on a search for sterile neutrinos by looking for a deficit in the number of neutral current interactions seen in the Far Detector. MINOS also has the potential to improve the limit on the neutrino mixing angle θ13 or make the first measurement of its value by searching for an electron neutrino appearance signal in the Far Detector. This is the focus of the study presented in this thesis. We developed a neural network based algorithm to

  16. A search for muon neutrino to electron neutrino oscillations in the MINOS Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Ochoa Ricoux, Juan Pedro [California Inst. of Technology (CalTech), Pasadena, CA (United States)

    2009-01-01

    We perform a search for vμ → ve oscillations, a process which would manifest a nonzero value of the θ13 mixing angle, in the MINOS long-baseline neutrino oscillation experiment. The analysis consists of searching for an excess of ve charged-current candidate events over the predicted backgrounds, made mostly of neutral-current events with high electromagnetic content. A novel technique to select electron neutrino events is developed, which achieves an improved separation between the signal and the backgrounds, and which consequently yields a better reach in θ13. The backgrounds are predicted in the Far Detector from Near Detector measurements. An excess is observed in the Far Detector data over the predicted backgrounds, which is consistent with the background-only hypothesis at 1.2 standard deviations.

  17. Neutral current induced neutrino oscillations in a supernova

    CERN Document Server

    Kusenko, A; Kusenko, Alexander; Segre, Gino

    1997-01-01

    Neutral currents induced matter oscillations of electroweak-active (anti-)neutrinos to sterile neutrinos can explain the observed motion of pulsars. In contrast to a recently proposed explanation of the pulsar birth velocities based on the electron to tau (muon) neutrino oscillations [hep-ph/9606428], the heaviest neutrino (either active or sterile) would have to have mass of order several keV.

  18. Search for muon to electron neutrino oscillations

    International Nuclear Information System (INIS)

    Vilain, P.; Wilquet, G.; Beyer, R.; Flegel, W.; Mouthuy, T.; Oeveraas, H.; Panman, J.; Rozanov, A.; Winter, K.; Zacek, G.; Zacek, V.; Buesser, F.W.; Foos, C.; Gerland, L.; Layda, T.; Niebergall, F.; Raedel, G.; Staehelin, P.; Voss, T.; Favart, D.; Gregoire, G.; Knoops, E.; Lemaitre, V.; Gorbunov, P.; Grigoriev, E.; Khovansky, V.; Maslennikov, A.; Lippich, W.; Nathaniel, A.; Staude, A.; Vogt, J.; Cocco, A.G.; Ereditato, A.; Fiorillo, G.; Marchetti-Stasi, F.; Palladino, V.; Strolin, P.; Capone, A.; De Pedis, D.; Dore, U.; Frenkel-Rambaldi, A.; Loverre, P.F.; Macina, D.; Piredda, G.; Santacesaria, R.; Di Capua, E.; Ricciardi, S.; Saitta, B.; Akkus, B.; Arik, E.; Serin-Zeyrek, M.; Sever, R.; Tolun, P.; Zeyrek, M.T.; Hiller, K.; Nahnhauer, R.; Roloff, H.E.

    1994-01-01

    A search for ν μ → ν e and anti ν μ → anti ν e oscillations has been carried out with the CHARM II detector exposed to the CERN wide band neutrino beam. The data were collected over five years, alternating beams mainly composed of muon-neutrinos and muon-antineutrinos. The number of interactions of ν e and anti ν e observed is comparable with the number of events expected from flux calculations. For large squared mass differences the upper limits obtained on the mixing angle are sin 2 2θ -3 for ν μ oscillating to ν e and sin 2 2θ -3 for anti ν μ to anti ν e , at the 90% confidence level. Combining neutrino and antineutrino data the upper limit is 5.6 . 10 -3 . (orig.)

  19. Nonadiabatic three-neutrino oscillations in matter

    International Nuclear Information System (INIS)

    DOlivo, J.C.; Oteo, J.A.

    1996-01-01

    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. copyright 1996 The American Physical Society

  20. Neutrino oscillations and antiνsub(e)-e scattering

    International Nuclear Information System (INIS)

    Halls, B.; McKellar, B.H.J.

    1980-01-01

    Electron antineutrino-electron scattering is modified in the presence of neutrino mixing and neutrino oscillation. In the Weinberg-Salam model the results for reactor antineutrinos are insensitive to the degree of mixing, to the extent that the experiment of Reines, Gurr and Sobel cannot differentiate between no oscillation and complete disappearance of the electron antineutrinos from the beam

  1. Case for neutrino oscillations

    International Nuclear Information System (INIS)

    Ramond, P.

    1982-01-01

    The building of a machine capable of producing an intense, well-calibrated beam of muon neutrinos is regarded by particle physicists with keen interest because of its ability of studying neutrino oscillations. The possibility of neutrino oscillations has long been recognized, but it was not made necessary on theoretical or experimental grounds; one knew that oscillations could be avoided if neutrinos were massless, and this was easily done by the conservation of lepton number. The idea of grand unification has led physicists to question the existence (at higher energies) of global conservation laws. The prime examples are baryon-number conservation, which prevents proton decay, and lepton-number conservation, which keeps neutrinos massless, and therefore free of oscillations. The detection of proton decay and neutrino oscillations would therefore be an indirect indication of the idea of Grand Unification, and therefore of paramount importance. Neutrino oscillations occur when neutrinos acquire mass in such a way that the neutrino mass eigenstates do not match the (neutrino) eigenstates produced by the weak interactions. We shall study the ways in which neutrinos can get mass, first at the level of the standard SU 2 x U 1 model, then at the level of its Grand Unification Generalizations

  2. Neutrino Oscillation Physics

    International Nuclear Information System (INIS)

    Kayser, Boris

    2014-01-01

    To complement the neutrino-physics lectures given at the 2011 International School on Astro Particle Physics devoted to Neutrino Physics and Astrophysics (ISAPP 2011; Varenna, Italy), at the 2011 European School of High Energy Physics (ESHEP 2011; Cheila Gradistei, Romania), and, in modified form, at other summer schools, we present here a written description of the physics of neutrino oscillation. This description is centered on a new way of deriving the oscillation probability. We also provide a brief guide to references relevant to topics other than neutrino oscillation that were covered in the lectures

  3. Neutrino Oscillation Physics

    Energy Technology Data Exchange (ETDEWEB)

    Kayser, Boris [Fermilab (United States)

    2014-07-01

    To complement the neutrino-physics lectures given at the 2011 International School on Astro Particle Physics devoted to Neutrino Physics and Astrophysics (ISAPP 2011; Varenna, Italy), at the 2011 European School of High Energy Physics (ESHEP 2011; Cheila Gradistei, Romania), and, in modified form, at other summer schools, we present here a written description of the physics of neutrino oscillation. This description is centered on a new way of deriving the oscillation probability. We also provide a brief guide to references relevant to topics other than neutrino oscillation that were covered in the lectures.

  4. Neutrinos in the Electron

    International Nuclear Information System (INIS)

    Koschmieder, E. L.

    2007-01-01

    I will show that one half of the rest mass of the electron consists of electron neutrinos and that the other half of the rest mass of the electron consists of the mass in the energy of electric oscillations. With this composition we can explain the rest mass of the electron, its charge, its spin and its magnetic moment We have also determined the rest masses of the muon neutrino and the electron neutrino

  5. Collective neutrino oscillations and neutrino wave packets

    Energy Technology Data Exchange (ETDEWEB)

    Akhmedov, Evgeny; Lindner, Manfred [Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Kopp, Joachim, E-mail: akhmedov@mpi-hd.mpg.de, E-mail: jkopp@uni-mainz.de, E-mail: lindner@mpi-hd.mpg.de [PRISMA Cluster of Excellence and Mainz Institute for Theoretical Physics, Johannes Gutenberg University, 55099 Mainz (Germany)

    2017-09-01

    Effects of decoherence by wave packet separation on collective neutrino oscillations in dense neutrino gases are considered. We estimate the length of the wave packets of neutrinos produced in core collapse supernovae and the expected neutrino coherence length, and then proceed to consider the decoherence effects within the density matrix formalism of neutrino flavour transitions. First, we demonstrate that for neutrino oscillations in vacuum the decoherence effects are described by a damping term in the equation of motion of the density matrix of a neutrino as a whole (as contrasted to that of the fixed-momentum components of the neutrino density matrix). Next, we consider neutrino oscillations in ordinary matter and dense neutrino backgrounds, both in the adiabatic and non-adiabatic regimes. In the latter case we study two specific models of adiabaticity violation—one with short-term and another with extended non-adiabaticity. It is demonstrated that, while in the adiabatic case a damping term is present in the equation of motion of the neutrino density matrix (just like in the vacuum oscillation case), no such term in general appears in the non-adiabatic regime.

  6. Study of the appearance of oscillating electron neutrinos issued from muon neutrino beam in the K2K experiment

    International Nuclear Information System (INIS)

    Argyriades, J.

    2006-05-01

    The work presented in this thesis has been done in the K2K experiment. His principle consists in the use of a beam of muon neutrinos, which flux has been measured at short and long distances. Those data enable us to study the effects of neutrino oscillation, particularly by measuring ν μ disappearance. Although this is not an appearance experiment, electronic neutrinos oscillation has been searched. In spite of no signal of appearance, this study enables to constrain oscillation parameters (Δm 23 2 , sin 2 2θ 13 ). With one event for 1,07 expected event from background, the exclusion area edges are close to the best actual limits, provided by Chooz experiment. By setting Δm 23 2 .= 2,8.10 -3 eV 2 , a limit at 90% confident level is reached: sin 2 2θ 13 < 0,2. (author)

  7. A combined treatment of neutrino decay and neutrino oscillations

    International Nuclear Information System (INIS)

    Lindner, Manfred; Ohlsson, Tommy; Winter, Walter

    2001-01-01

    Neutrino decay in vacuum has often been considered as an alternative to neutrino oscillations. Because nonzero neutrino masses imply the possibility of both neutrino decay and neutrino oscillations, we present a model-independent formal treatment of these combined scenarios. For that, we show for the example of Majoron decay that in many cases decay products are observable and may even oscillate. Furthermore, we construct a minimal scenario in which we study the physical implications of neutrino oscillations with intermediate decays

  8. LSND neutrino oscillation results

    International Nuclear Information System (INIS)

    Louis, W.C.

    1996-01-01

    In the past several years, a number of experiments have searched for neutrino oscillations, where a neutrino of one type (say bar ν μ ) spontaneously transforms into a neutrino of another type (say bar ν e ). For this phenomenon to occur, neutrinos must be massive and the apparent conservation law of lepton families must be violated. In 1995 the LSND experiment published data showing candidate events that are consistent with bar ν μ oscillations. Additional data are reported here which provide stronger evidence for neutrino oscillations

  9. Neutrino masses and neutrino oscillations

    CERN Document Server

    Di Lella, L

    2000-01-01

    These lectures review direct measurements of neutrino masses and the status of neutrino oscillation searches using both natural neutrino sources (the Sun and cosmic rays interacting in the Earth atmosphere) and artificial neutrinos (produced by nuclear reactors and accelerators). Finally, future experiments and plans are presented. (68 refs).

  10. A combined muon-neutrino and electron-neutrino oscillation search at MiniBooNE

    Energy Technology Data Exchange (ETDEWEB)

    Monroe, Jocelyn Rebecca [Columbia Univ., New York, NY (United States)

    2006-01-01

    MiniBooNE seeks to corroborate or refute the unconfirmed oscillation result from the LSND experiment. If correct, the result implies that a new kind of massive neutrino, with no weak interactions, participates in neutrino oscillations. MiniBooNE searches for vμ → ve oscillations with the Fermi National Accelerator Laboratory 8 GeV beam line, which produces a vμ beam with an average energy of ~ 0.8 GeV and an intrinsic ve content of 0.4%. The neutrino detector is a 6.1 m radius sphere filled with CH2, viewed by 1540 photo-multiplier tubes, and located 541 m downstream from the source. This work focuses on the estimation of systematic errors associated with the neutrino flux and neutrino interaction cross section predictions, and in particular, on constraining these uncertainties using in-situ MiniBooNE vμ charged current quasielastic (CCQE) scattering data. A data set with ~ 100,000 events is identified, with 91% CCQE purity. This data set is used to measure several parameters of the CCQE cross section: the axial mass, the Fermi momentum, the binding energy, and the functional dependence of the axial form factor on four-momentum transfer squared. Constraints on the vμ and ve fluxes are derived using the vμ CCQE data set. A Monte Carlo study of a combined vμ disappearance and ve appearance oscillation fit is presented, which improves the vμ → ve oscillation sensitivity of MiniBooNE with respect to a ve appearance-only fit by 1.2-1.5σ, depending on the value of Δm2.

  11. Neutrino Oscillations Physics

    Science.gov (United States)

    Fogli, Gianluigi

    2005-06-01

    We review the status of the neutrino oscillations physics, with a particular emphasis on the present knowledge of the neutrino mass-mixing parameters. We consider first the νμ → ντ flavor transitions of atmospheric neutrinos. It is found that standard oscillations provide the best description of the SK+K2K data, and that the associated mass-mixing parameters are determined at ±1σ (and NDF = 1) as: Δm2 = (2.6 ± 0.4) × 10-3 eV2 and sin 2 2θ = 1.00{ - 0.05}{ + 0.00} . Such indications, presently dominated by SK, could be strengthened by further K2K data. Then we point out that the recent data from the Sudbury Neutrino Observatory, together with other relevant measurements from solar and reactor neutrino experiments, in particular the KamLAND data, convincingly show that the flavor transitions of solar neutrinos are affected by Mikheyev-Smirnov-Wolfenstein (MSW) effects. Finally, we perform an updated analysis of two-family active oscillations of solar and reactor neutrinos in the standard MSW case.

  12. Neutrino mixing, oscillations and decoherence in astrophysics and cosmology

    Science.gov (United States)

    Ho, Chiu Man

    2007-08-01

    This thesis focuses on a finite-temperature field-theoretical treatment of neutrino oscillations in hot and dense media. By implementing the methods of real-time non-equilibrium field theory, we study the dynamics of neutrino mixing, oscillations, decoherence and relaxation in astrophysical and cosmological environments. We first study neutrino oscillations in the early universe in the temperature regime prior to the epoch of Big Bang Nucleosynthesis (BBN). The dispersion relations and mixing angles in the medium are found to be helicity-dependent, and a resonance like the Mikheyev-Smirnov- Wolfenstein (MSW) effect is realized. The oscillation time scales are found to be longer near a resonance and shorter for off-resonance high-energy neutrinos. We then investigate the space-time propagation of neutrino wave-packets just before BBN. A phenomenon of " frozen coherence " is found to occur if the longitudinal dispersion catches up with the progressive separation between the mass eigenstates, before the coherence time limit has been reached. However, the transverse dispersion occurs at a much shorter scale than all other possible time scales in the medium, resulting in a large suppression in the transition probabilities from electron-neutrino to muon-neutrino. We also explore the possibility of charged lepton mixing as a consequence of neutrino mixing in the early Universe. We find that charged leptons, like electrons and muons, can mix and oscillate resonantly if there is a large lepton asymmetry in the neutrino sector. We study sterile neutrino production in the early Universe via active-sterile oscillations. We provide a quantum field theoretical reassessment of the quantum Zeno suppression on the active-to-sterile transition probability and its time average. We determine the complete conditions for quantum Zeno suppression. Finally, we examine the interplay between neutrino mixing, oscillations and equilibration in a thermal medium, and the corresponding non

  13. Neutrino oscillations at proton accelerators

    International Nuclear Information System (INIS)

    Michael, Douglas

    2002-01-01

    Data from many different experiments have started to build a first glimpse of the phenomenology associated with neutrino oscillations. Results on atmospheric and solar neutrinos are particularly clear while a third result from LSND suggests a possibly very complex oscillation phenomenology. As impressive as the results from current experiments are, it is clear that we are just getting started on a long-term experimental program to understand neutrino masses, mixings and the physics which produce them. A number of exciting fundamental physics possibilities exist, including that neutrino oscillations could demonstrate CP or CPT violation and could be tied to exotic high-energy phenomena including strings and extra dimensions. A complete exploration of oscillation phenomena demands many experiments, including those possible using neutrino beams produced at high energy proton accelerators. Most existing neutrino experiments are statistics limited even though they use gigantic detectors. High intensity proton beams are essential for producing the intense neutrino beams which we need for next generation neutrino oscillation experiments

  14. Neutrino Oscillations at Proton Accelerators

    Science.gov (United States)

    Michael, Douglas

    2002-12-01

    Data from many different experiments have started to build a first glimpse of the phenomenology associated with neutrino oscillations. Results on atmospheric and solar neutrinos are particularly clear while a third result from LSND suggests a possibly very complex oscillation phenomenology. As impressive as the results from current experiments are, it is clear that we are just getting started on a long-term experimental program to understand neutrino masses, mixings and the physics which produce them. A number of exciting fundamental physics possibilities exist, including that neutrino oscillations could demonstrate CP or CPT violation and could be tied to exotic high-energy phenomena including strings and extra dimensions. A complete exploration of oscillation phenomena demands many experiments, including those possible using neutrino beams produced at high energy proton accelerators. Most existing neutrino experiments are statistics limited even though they use gigantic detectors. High intensity proton beams are essential for producing the intense neutrino beams which we need for next generation neutrino oscillation experiments.

  15. SOLAR NEUTRINO PHYSICS OSCILLATIONS: SENSITIVITY TO THE ELECTRONIC DENSITY IN THE SUN'S CORE

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, Ilidio [Centro Multidisciplinar de Astrofisica, Instituto Superior Tecnico, Universidade Tecnica de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Turck-Chieze, Sylvaine, E-mail: ilidio.lopes@ist.utl.pt, E-mail: ilopes@uevora.pt, E-mail: sylvaine.turck-chieze@cea.fr [CEA/IRFU/Service d' Astrophysique, CE Saclay, F-91191 Gif sur Yvette (France)

    2013-03-01

    Solar neutrinos coming from different nuclear reactions are now detected with high statistics. Consequently, an accurate spectroscopic analysis of the neutrino fluxes arriving on Earth's detectors becomes available, in the context of neutrino oscillations. In this work, we explore the possibility of using this information to infer the radial profile of the electronic density in the solar core. So, we discuss the constraints on the Sun's density and chemical composition that can be determined from solar neutrino observations. This approach constitutes an independent and alternative diagnostic to the helioseismic investigations already done. The direct inversion method, which we propose to obtain the radial solar electronic density profile, is almost independent of the solar model.

  16. Effects of neutrino oscillations on nucleosynthesis and neutrino signals for an 18 M⊙ supernova model

    Science.gov (United States)

    Wu, Meng-Ru; Qian, Yong-Zhong; Martínez-Pinedo, Gabriel; Fischer, Tobias; Huther, Lutz

    2015-03-01

    In this paper, we explore the effects of neutrino flavor oscillations on supernova nucleosynthesis and on the neutrino signals. Our study is based on detailed information about the neutrino spectra and their time evolution from a spherically symmetric supernova model for an 18 M⊙ progenitor. We find that collective neutrino oscillations are not only sensitive to the detailed neutrino energy and angular distributions at emission, but also to the time evolution of both the neutrino spectra and the electron density profile. We apply the results of neutrino oscillations to study the impact on supernova nucleosynthesis and on the neutrino signals from a Galactic supernova. We show that in our supernova model, collective neutrino oscillations enhance the production of rare isotopes 138La and 180Ta but have little impact on the ν p -process nucleosynthesis. In addition, the adiabatic Mikheyev-Smirnov-Wolfenstein flavor transformation, which occurs in the C /O and He shells of the supernova, may affect the production of light nuclei such as 7Li and 11B. For the neutrino signals, we calculate the rate of neutrino events in the Super-Kamiokande detector and in a hypothetical liquid argon detector. Our results suggest the possibility of using the time profiles of the events in both detectors, along with the spectral information of the detected neutrinos, to infer the neutrino mass hierarchy.

  17. Measurement of atmospheric neutrino oscillations and matter effects with PINGU

    Energy Technology Data Exchange (ETDEWEB)

    Coenders, Stefan; Euler, Sebastian; Krings, Kai; Vehring, Markus; Wallraff, Marius; Wiebusch, Christopher [RWTH Aachen Univ. (Germany). III. Physikalisches Inst.; Collaboration: IceCube-Collaboration

    2013-07-01

    With IceCube's low-energy extension DeepCore the first significant effects of atmospheric neutrino oscillations have been observed. The planned ''Precision Icecube Next Generation Upgrade'' (PINGU) inside DeepCore will lower the energy threshold to a few GeV, where matter effects of neutrino oscillations have to be taken into account. The Mikheyev-Smirnov-Wolfenstein (MSW) effect modifies the mixing between flavor and mass eigenstates of the neutrinos, resulting in stronger oscillations. Furthermore, neutrinos when passing through the Earth core experience parametric enhancement due to multiple discontinuities in the electron density. In this talk the effects of matter oscillations and the capabilities to measure these effects with PINGU are investigated.

  18. Again on neutrino oscillations

    International Nuclear Information System (INIS)

    Bilenky, S.M.; Pontecorvo, B.

    1976-01-01

    The general case is treated of a weak interaction theory in which a term violating lepton charges is present. In such a scheme the particles with definite masses are Majorana neutrinos (2N if in the weak interaction participate N four-component neutrinos). Neutrino oscillations are discussed and it is shown that the minimum average intensity at the earth of solar neutrinos is 1/2N of the intensity expected when oscillations are absent

  19. Neutrino Oscillation Results from NOvA

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    NOvA is an accelerator long-baseline neutrino oscillation experiment optimised to measure electron neutrino appearance in a high-purity beam of muon neutrinos from Fermilab. The exciting discovery of the theta13 neutrino mixing angle in 2012 has opened a door to making multiple new measurements of neutrinos. These include leptonic CP violation, the neutrino mass ordering and the octant of theta23. NOvA with its 810km baseline and higher energy beam has about triple the matter effect of T2K which opens a new window on the neutrino mass ordering. With about 20% of our design beam exposure and significant analysis improvements we have recently released updated results. I will present both our disappearance and appearance measurements.

  20. Constraints on decay plus oscillation solutions of the solar neutrino problem

    Science.gov (United States)

    Joshipura, Anjan S.; Massó, Eduard; Mohanty, Subhendra

    2002-12-01

    We examine the constraints on the nonradiative decay of neutrinos from the observations of solar neutrino experiments. The standard oscillation hypothesis among three neutrinos solves the solar and atmospheric neutrino problems. The decay of a massive neutrino mixed with the electron neutrino results in the depletion of the solar neutrino flux. We introduce neutrino decay in the oscillation hypothesis and demand that decay does not spoil the successful explanation of solar and atmospheric observations. We obtain a lower bound on the ratio of the lifetime over the mass of ν2, τ2/m2>22.7 s/MeV for the Mikheyev-Smirnov-Wolfenstein solution of the solar neutrino problem and τ2/m2>27.8 s/MeV for the vacuum oscillation solution (at 99% C.L.).

  1. Neutrino oscillations: present status and outlook

    International Nuclear Information System (INIS)

    Schwetz, T.

    2005-01-01

    In this talk the present status of neutrino oscillations is reviewed, based on a global analysis of world neutrino oscillation data from solar, atmospheric, reactor, and accelerator neutrino experiments. Furthermore, I discuss the expected improvements in the determination of neutrino parameters by future oscillation experiments within a timescale of 10 years. (author)

  2. Neutrino conversion in a neutrino flux: towards an effective theory of collective oscillations

    Science.gov (United States)

    Hansen, Rasmus S. L.; Smirnov, Alexei Yu.

    2018-04-01

    Collective oscillations of supernova neutrinos above the neutrino sphere can be completely described by the propagation of individual neutrinos in external potentials and are in this sense a linear phenomenon. An effective theory of collective oscillations can be developed based on certain assumptions about time dependence of these potentials. General conditions for strong flavor transformations are formulated and these transformations can be interpreted as parametric resonance effects induced by periodic modulations of the potentials. We study a simplified and solvable example, where a probe neutrino is propagating in a flux of collinear neutrinos, such that ν ν‑ interactions in the flux are absent. Still, this example retains the main feature—the coherent flavor exchange. Properties of the parametric resonance are studied, and it is shown that integrations over energies and emission points of the flux neutrinos suppress modulations of the potentials and therefore strong transformations. The transformations are also suppressed by changes in densities of background neutrinos and electrons.

  3. Neutrino oscillations. Theory and experiment

    International Nuclear Information System (INIS)

    Beshtoev, Kh.M.

    2001-01-01

    Theoretical schemes on neutrino oscillations are considered. The experimental data on neutrino oscillations obtained in the Super-Kamiokande (Japan) and SNO (Canada) experiments are given. Comparison of these data with the predictions obtained in the theoretical schemes is done. Conclusion is made that the experimental data confirm only the scheme with transitions (oscillations) between aromatic ν e -, ν μ -, ν τ - neutrinos with maximal angle mixings. (author)

  4. Neutrino oscillation: status and outlooks

    International Nuclear Information System (INIS)

    Nedelec, P.

    1994-01-01

    Whether the neutrinos are massive or not is one of the most puzzling question of physics today. If they are massive, they can contribute significantly to the Dark Matter of the Universe. An other consequence of a non-zero mass of neutrinos is that they might oscillate from one flavor to another. This oscillation process is by now the only way to detect a neutrino with a mass in the few eV range. Several neutrino experiments are currently looking for such an oscillation, in different modes, using different techniques. An overview of the experimental situation for neutrino experiments at accelerators is given. (author). 9 refs., 5 figs., 5 tabs

  5. Supernova Neutrino-Process and Implication in Neutrino Oscillation

    Science.gov (United States)

    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, θ13 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.

  6. Study of the appearance of oscillating electron neutrinos issued from muon neutrino beam in the K2K experiment; Etude de l'apparition de neutrinos electroniques oscillant a partir de neutrinos muoniques du faisceau de l'experience K2K

    Energy Technology Data Exchange (ETDEWEB)

    Argyriades, J

    2006-05-15

    The work presented in this thesis has been done in the K2K experiment. His principle consists in the use of a beam of muon neutrinos, which flux has been measured at short and long distances. Those data enable us to study the effects of neutrino oscillation, particularly by measuring {nu}{sub {mu}} disappearance. Although this is not an appearance experiment, electronic neutrinos oscillation has been searched. In spite of no signal of appearance, this study enables to constrain oscillation parameters ({delta}m{sub 23}{sup 2}, sin{sup 2}2{theta}{sub 13}). With one event for 1,07 expected event from background, the exclusion area edges are close to the best actual limits, provided by Chooz experiment. By setting {delta}m{sub 23}{sup 2}.= 2,8.10{sup -3} eV{sup 2}, a limit at 90% confident level is reached: sin{sup 2}2{theta}{sub 13} < 0,2. (author)

  7. New results from the T2K neutrino oscillation experiment

    Energy Technology Data Exchange (ETDEWEB)

    Oser, Scott M., E-mail: oser@phas.ubc.ca [University of British Columbia, Department of Physics and Astronomy (Canada); Collaboration: T2K Collaboration

    2013-03-15

    The T2K experiment searches for the appearance of electron neutrinos in a muon neutrino beam. The rate of this process is sensitive to the neutrino mixing parameter {theta}{sub 13}. Recent measurements that {theta}{sub 13} {ne} 0 imply that {nu}{sub {mu}} {yields} {nu}{sub e} oscillations should be observable. Using all data through May 15, 2012 the T2K experiment has detected 10 candidate {nu}{sub e} events, with an expected background for {theta}{sub 13} = 0 of 2.73{+-}0.37 events. This 3.2{sigma} excess of {nu}{sub e} events is the strongest indication to date for appearance of electron neutrinos in a neutrino oscillation experiment, and for normal mass hierarchy and {delta}{sub CP} = 0 yields 0.059 < sin{sup 2} 2{theta}{sub 13} < 0.164 at the 68 % C.L.

  8. Accelerator-based neutrino oscillation searches

    International Nuclear Information System (INIS)

    Whitehouse, D.A.; Rameika, R.; Stanton, N.

    1993-01-01

    This paper attempts to summarize the neutrino oscillation section of the Workshop on Future Directions in Particle and Nuclear Physics at Multi-GeV Hadron Beam Facilities. There were very lively discussions about the merits of the different oscillation channels, experiments, and facilities, but we believe a substantial consensus emerged. First, the next decade is one of great potential for discovery in neutrino physics, but it is also one of great peril. The possibility that neutrino oscillations explain the solar neutrino and atmospheric neutrino experiments, and the indirect evidence that Hot Dark Matter (HDM) in the form of light neutrinos might make up 30% of the mass of the universe, point to areas where accelerator-based experiments could play a crucial role in piecing together the puzzle. At the same time, the field faces a very uncertain future. The LSND experiment at LAMPF is the only funded neutrino oscillation experiment in the United States and it is threatened by the abrupt shutdown of LAMPF proposed for fiscal 1994. The future of neutrino physics at the Brookhaven National Laboratory AGS depends the continuation of High Energy Physics (HEP) funding after the RHIC startup. Most proposed neutrino oscillation searches at Fermilab depend on the completion of the Main Injector project and on the construction of a new neutrino beamline, which is uncertain at this point. The proposed KAON facility at TRIUMF would provide a neutrino beam similar to that at the AGS but with a much increase intensity. The future of KAON is also uncertain. Despite the difficult obstacles present, there is a real possibility that we are on the verge of understanding the masses and mixings of the neutrinos. The physics importance of such a discovery can not be overstated. The current experimental status and future possibilities are discussed below

  9. Beta Beams for Precision Measurements of Neutrino Oscillation Parameters

    CERN Document Server

    Wildner, E; Hansen, C; De Melo Mendonca, T; Stora, T; Damjanovic, S; Payet, J; Chancé, A; Zorin, V; Izotov, I; Rasin, S; Sidorov, A; Skalyga, V; De Angelis, G; Prete, G; Cinausero, M; Kravchuk, V; Gramegna, F; Marchi, T; Collazuol, G; Mezzetto, M; Delbar, T; Loiselet, M; Keutgen, T; Mitrofanov, S; Burt, G; Dexter, A; Lamy, T; Latrasse, L; Marie-Jeanne, M; Sortais, P; Thuillier, T; Debray, F; Trophime, C; Hass, M; Hirsh, T; Berkovits, D; Stahl, A; Vardaci, E; Di Nitto, A; Brondi, A; La Rana, G; Moro, R; De Rosa, G; Palladino, V

    2012-01-01

    Neutrino oscillations have implications for the Standard Model of particle physics. The CERN Beta Beam has outstanding capabilities to contribute to precision measurements of the parameters governing neutrino oscillations. The FP7 collaboration EUROnu (2008-2012) is a design study that will review three facilities (Super-Beams, Beta Beams and Neutrino Factories) and perform a cost assessment that, coupled with the physics performance, will give means to the European research authorities to make decisions on future European neutrino oscillation facilities. ”Beta Beams” produce collimated pure electron (anti)neutrinos by accelerating beta active ions to high energies and having them decay in a storage ring. Using existing machines and infrastructure is an advantage for the cost evaluation; however, this choice is also constraining the Beta Beams. Recent work to make the Beta Beam facility a solid option will be described: production of Beta Beam isotopes, the 60 GHz pulsed ECR source development, integratio...

  10. Search for Muon neutrino → Tau neutrino oscillations motivation and feasibility

    International Nuclear Information System (INIS)

    Zacek, V.

    1988-01-01

    Theoretical prejudices derived from solar-neutrino matter oscillations and assumptions of neutrino mass hierarchies suggest, that neutrino-oscillations are observable in laboratory with mass parameters of Δm 2 = 10 -3 -10 4 eV 2 . In particular Muon neutrino → Tau neutrino appearance searches at accelerators seem strongly motivated

  11. Three flavour oscillation interpretation of neutrino data

    Indian Academy of Sciences (India)

    To explain the atmospheric neutrino problem in terms of neutrino oscillations, ЖС¾ of about 10-¿. eV. ¾. [8] is needed whereas the neutrino oscil- lation solution to the solar neutrino problem requires ЖС¾ ~10- eV. ¾ . Hence both solar and atmospheric neutrino problems cannot be explained in terms of e ° μ oscillations.

  12. Neutrino Oscillation Experiment at JHF

    CERN Multimedia

    2002-01-01

    T2K is a long baseline neutrino experiment designed to investigate how neutrinos change from one flavor to another as they travel (neutrino oscillations). An intense beam of muon neutrinos is generated at the J-PARC nuclear physics site on the East coast of Japan and directed across the country to the Super-Kamiokande neutrino detector in the mountains of western Japan. The beam is measured once before it leaves the J-PARC site, using the near detector ND280, and again at Super-K, 295 km away: the change in the measured intensity and composition of the beam is used to provide information on the properties of neutrinos. The high intensity neutrino beam is produced in an off-axis configuration. The peak neutrino energy is tuned to the oscillation maximum of ∼ 0.6 GeV to maximize the sensitivity to neutrino oscillations. The science goals of T2K can be summarized as follows: •\tsearch for CP violation in the neutrino sector •\tdiscovery of νμ → νe ( i.e. the confirmation that θ13 > 0 ) •\tprecision ...

  13. Majorana mass term, Dirac neutrinos and selective neutrino oscillations

    International Nuclear Information System (INIS)

    Leung, C.N.

    1987-01-01

    In a theory of neutrino mixing via a Majorana mass term involving only the left-handed neutrinos there exist selection rules for neutrino oscillations if true Dirac and/or exactly zero mass eigenstates are present. In the case of three neutrino flavours no oscillation is allowed if the mass spectrum contains one Dirac and one nondegenerate Majorana massive neutrino. The origin of these selection rules and their implications are discussed and the number of possible CP-violating phases in the lepton mixing matrix when Dirac and Majorana mass eigenstates coexist is given. (orig.)

  14. Reactor Neutrino Oscillations: KamLAND and KASKA

    International Nuclear Information System (INIS)

    Suekane, F.

    2006-01-01

    Nuclear reactors generate a huge number of low energy ν-bar e 's. The reactor neutrinos have been used to study properties of neutrinos since its discovery a half century ago. Recently, KamLAND group finally discovered reactor neutrino oscillation with average baseline 180 km. According to the 3 flavor scheme of standard theory and measured oscillation parameters so far, the reactor neutrino is expected to perform another type of small oscillation at a baseline 1.8 km. KASKA experiment is a project to detect this small oscillation and to measure the last neutrino mixing angle θ 13 by using the world most powerful reactor complex, Kashiwazaki-Kariwa nuclear power station. In this proceedings, phenomena of neutrino oscillation and the two reactor oscillation experiments, KamLAND and KASKA, are introduced

  15. Neutrino-Electron Scattering in MINERvA for Constraining the NuMI Neutrino Flux

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jaewon [Univ. of Rochester, NY (United States)

    2013-01-01

    Neutrino-electron elastic scattering is used as a reference process to constrain the neutrino flux at the Main Injector (NuMI) beam observed by the MINERvA experiment. Prediction of the neutrino flux at accelerator experiments from other methods has a large uncertainty, and this uncertainty degrades measurements of neutrino oscillations and neutrino cross-sections. Neutrino-electron elastic scattering is a rare process, but its cross-section is precisely known. With a sample corresponding to $3.5\\times10^{20}$ protons on target in the NuMI low-energy neutrino beam, a sample of $120$ $\

  16. Evidence for neutrino oscillations in the Sudbury Neutrino Observatory

    International Nuclear Information System (INIS)

    Marino, Alysia Diane

    2004-01-01

    The Sudbury Neutrino Observatory (SNO) is a large-volume heavy water Cerenkov detector designed to resolve the solar neutrino problem. SNO observes charged-current interactions with electron neutrinos, neutral-current interactions with all active neutrinos, and elastic-scattering interactions primarily with electron neutrinos with some sensitivity to other flavors. This dissertation presents an analysis of the solar neutrino flux observed in SNO in the second phase of operation, while ∼2 tonnes of salt (NaCl) were dissolved in the heavy water. The dataset here represents 391 live days of data. Only the events above a visible energy threshold of 5.5 MeV and inside a fiducial volume within 550 cm of the center of the detector are studied. The neutrino flux observed via the charged-current interaction is [1.71 ± 0.065(stat.)± 0.068 0.065 (sys.)±0.02(theor.)] x 10 6 cm -2 s -1 , via the elastic-scattering interaction is [2.21±0.22(stat.)± 0.12 0.11 (sys.)±0.01(theor.)] x 10 6 cm -2 s -1 , and via the neutral-current interaction is [5.05±0.23(stat.)± 0.37 0.31 (sys.)±0.06(theor.)] x 10 6 cm -2 s -1 . The electron-only flux seen via the charged-current interaction is more than 7σ below the total active flux seen via the neutral-current interaction, providing strong evidence that neutrinos are undergoing flavor transformation as they travel from the core of the Sun to the Earth. The most likely origin of the flavor transformation is matter-induced flavor oscillation

  17. First Detection of Low Energy Electron Neutrinos in Liquid Argon Time Projection Chambers

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Corey James [Yale U.

    2016-01-01

    Electron neutrino appearance is the signature channel to address the most pressing questions in neutrino oscillations physics, at both long and short baselines. This includes the search for CP violation in the neutrino sector, which the U.S. flagship neutrino experiment DUNE will address. In addition, the Short Baseline Neutrino Program at Fermilab (MicroBooNE, SBND, ICARUS-T600) searches for new physics, such as sterile neutrinos, through electron neutrino appearance. Liquid argon time projection chambers are the forefront of neutrino detection technology, and the detector of choice for both short and long baseline neutrino oscillation experiments. This work presents the first experimental observation and study of electron neutrinos in the 1-10 GeV range, the essential oscillation energy regime for the above experiments. The systematic uncertainties for an electron neutrino appearance search for the Fermilab Short Baseline Neutrino Program are carefully quantified, and the characterization of separation between electrons and high energy photons is examined.

  18. Electrons for Neutrinos: Using Electron Scattering to Develop New Energy Reconstruction for Future Deuterium-Based Neutrino Detectors

    Science.gov (United States)

    Silva, Adrian; Schmookler, Barak; Papadopoulou, Afroditi; Schmidt, Axel; Hen, Or; Khachatryan, Mariana; Weinstein, Lawrence

    2017-09-01

    Using wide phase-space electron scattering data, we study a novel technique for neutrino energy reconstruction for future neutrino oscillation experiments. Accelerator-based neutrino oscillation experiments require detailed understanding of neutrino-nucleus interactions, which are complicated by the underlying nuclear physics that governs the process. One area of concern is that neutrino energy must be reconstructed event-by-event from the final-state kinematics. In charged-current quasielastic scattering, Fermi motion of nucleons prevents exact energy reconstruction. However, in scattering from deuterium, the momentum of the electron and proton constrain the neutrino energy exactly, offering a new avenue for reducing systematic uncertainties. To test this approach, we analyzed d (e ,e' p) data taken with the CLAS detector at Jefferson Lab Hall B and made kinematic selection cuts to obtain quasielastic events. We estimated the remaining inelastic background by using d (e ,e' pπ-) events to produce a simulated dataset of events with an undetected π-. These results demonstrate the feasibility of energy reconstruction in a hypothetical future deuterium-based neutrino detector. Supported by the Paul E. Gray UROP Fund, MIT.

  19. Accelerator studies of neutrino oscillations

    CERN Document Server

    Ereditato, A

    2000-01-01

    The question of whether the neutrino has a non-vanishing mass plays acrucial role in particle physics. A massive neutrino would unambiguously reveal the existence of new physics beyond the Standard Model. In addition, it could have profound implications on astrophysics and cosmology, with effects on the evolution of the Universe. Experiments aiming at direct neutrino-mass measurements based on kinematics have not been able, so far, to measure the very small neutrino mass. Indirect measurements can be performed by exploiting reactions which may only occur for massive neutrinos. Neutrino oscillation is one of those processes. The mass difference between neutrino mass-eigenstates can be inferred from a phase measurement. This feature allows for high sensitivity experiments. Neutrinos from different sources can be used to search for oscillations: solar neutrinos, neutrinos produced in the interaction of cosmic rays with the atmosphere and artificially produced neutrinos from nuclear reactors and particle accelera...

  20. Oscillation effects on high-energy neutrino fluxes from astrophysical hidden sources

    International Nuclear Information System (INIS)

    Mena, Olga; Mocioiu, Irina; Razzaque, Soebur

    2007-01-01

    High-energy neutrinos are expected to be produced in a variety of astrophysical sources as well as in optically thick hidden sources. We explore the matter-induced oscillation effects on emitted neutrino fluxes of three different flavors from the latter class. We use the ratio of electron and tau induced showers to muon tracks, in upcoming neutrino telescopes, as the principal observable in our analysis. This ratio depends on the neutrino energy, density profile of the sources, and on the oscillation parameters. The largely unknown flux normalization drops out of our calculation and only affects the statistics. For the current knowledge of the oscillation parameters we find that the matter-induced effects are non-negligible and the enhancement of the ratio from its vacuum value takes place in an energy range where the neutrino telescopes are the most sensitive. Quantifying the effect would be useful to learn about the astrophysics of the sources as well as the oscillation parameters. If the neutrino telescopes mostly detect diffuse neutrinos without identifying their sources, then any deviation of the measured flux ratios from the vacuum expectation values would be most naturally explained by a large population of hidden sources for which matter-induced neutrino oscillation effects are important

  1. A search for muon neutrino to electron neutrino oscillations at Δm2 > 0.1 eV2

    Energy Technology Data Exchange (ETDEWEB)

    Patterson, Ryan Benton [Princeton Univ., NJ (United States)

    2007-11-01

    The evidence is compelling that neutrinos undergo flavor change as they propagate. In recent years, experiments have observed this phenomenon of neutrino oscillations using disparate neutrino sources: the sun, fission reactors, accelerators, and secondary cosmic rays. The standard model of particle physics needs only simple extensions - neutrino masses and mixing - to accommodate all neutrino oscillation results to date, save one. The 3.8σ-significant $\\bar{v}$e excess reported by the LSND collaboration is consistent with $\\bar{v}$μ →$\\bar{v}$e oscillations with a mass-squared splitting of Δm2 ~ 1 eV2. This signal, which has not been independently verified, is inconsistent with other oscillation evidence unless more daring standard model extensions (e.g. sterile neutrinos) are considered.

  2. Movable detector to search for neutrino oscillations in the BNL neutrino beam

    International Nuclear Information System (INIS)

    Bozoki, G.; Fainberg, A.; Weygand, D.; Fagg, L.; Uberall, H.; Goldberg, M.; Meadows, B.; Saenz, A.W.; Seeman, N.

    1980-01-01

    A simple, straightforward, and economic experiment utilizing a set of water Cherenkov counters is proposed to search for neutrino oscillations in the AGS neutrino beam. The detector will be movable and will be able to provide reasonable counting rates up to 2 km downstream of the pion decay tunnel. Whereas previous accelerator experiments have sought to increase the ratio l/p (with l the neutrino path length and p its momentum) by decreasing p, increasing l is suggested instead. Further, by making measurements at several different values of l with the same apparatus, many sources of systematic error are eliminated. The experiment will measure beam-associated muon- and electron-type events at each position. A change in the ratio of muon- to electron-type events as a function of position would be evidence for ν/sub μ/ + ν/sub e/ oscillations. Sensitivity in terms of (Δm) 2 (the square of the mass difference in the mass eigenstates) can be as low as 0.1 eV 2 , for full mixing, which is below the most probable value found by Reines et al for Δm 2 in their electron neutrino reactor experiment. This experiment would be parasitic, running behind the usual neutrino beam experiments, assuming the nominal beam energy (peaked at 1 GeV), and would thus make a minimal demand on AGS support. It is suggested that the first two measurements be made inside the Isabelle tunnel at the points of intersection with the AGS neutrino beam. No further excavations would be required, and the data could be taken before ISA equipment is installed

  3. Mass and oscillations of Dirac neutrinos

    International Nuclear Information System (INIS)

    Collot, J.

    1989-01-01

    In the most economical extension of the standard model, we have presented the theory of massive Dirac neutrinos. We have particularly emphasized that, in this model, a complete analogy between quarks and leptons can be erected and predicts neutrino flavor oscillations. We have reviewed the last experimental results concerning kinetic neutrino mass experiments and neutrino oscillation investigations

  4. Neutrino Oscillations:. a Phenomenological Approach

    Science.gov (United States)

    Fogli, G. L.; Lisi, E.; Marrone, A.; Palazzo, A.; Rotunno, A. M.; Montanino, D.

    We review the status of the neutrino oscillations physics, with a particular emphasis on the present knowledge of the neutrino mass-mixing parameters. We consider first the νμ → ντ flavor transitions of atmospheric neutrinos. It is found that standard oscillations provide the best description of the SK+K2K data, and that the associated mass-mixing parameters are determined at ±1σ (and NDF = 1) as: Δm2 = (2.6 ± 0.4) × 10-3 eV2 and sin 2 2θ = 1.00{ - 0.05}{ + 0.00} . Such indications, presently dominated by SK, could be strengthened by further K2K data. Then we point out that the recent data from the Sudbury Neutrino Observatory, together with other relevant measurements from solar and reactor neutrino experiments, in particular the KamLAND data, convincingly show that the flavor transitions of solar neutrinos are affected by Mikheyev-Smirnov-Wolfenstein (MSW) effects. Finally, we perform an updated analysis of two-family active oscillations of solar and reactor neutrinos in the standard MSW case.

  5. Neutrino oscillations make their first appearance in OPERA

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    1400 metres underground in the INFN Gran Sasso Laboratory, the Opera experiment has just observed its first candidate for neutrino oscillation – the phenomenon that confirms that neutrinos have mass. It is the first time that an experiment has observed the direct appearance of the new type of neutrinos produced in the oscillation. Opera uses a dedicated beam produced at CERN’s Super Proton Synchrotron (SPS).   Tracks of first candidate event observed by the OPERA experiment. Neutrinos, abundant in cosmic rays, are involved in several of the nuclear reactions that take place in the Sun, and also in radioactive decays. Numerous as they are, they continue to hold many secrets for scientists. One is the fact that the three types of neutrinos—electron, muon and tau neutrinos—can change into each another. This physical phenomenon, known as neutrino ‘oscillations’, was originally described in an article by Bruno Pontecorvo and Vla...

  6. Beta Beams: an accelerator based facility to explore Neutrino oscillation physics

    CERN Document Server

    Wildner, E; Hansen, C; De Melo Mendonca, T; Stora, T; Payet, J; Chance, A; Zorin, V; Izotov, I; Rasin, S; Sidorov, A; Skalyga, V; De Angelis, G; Prete, G; Cinausero, M; Kravchuk, VL; Gramegna, F; Marchi, T; Collazuol, G; De Rosa, G; Delbar, T; Loiselet, M; Keutgen, T; Mitrofanov, S; Lamy, T; Latrasse, L; Marie-Jeanne, M; Sortais, P; Thuillier, T; Debray, F; Trophime, C; Hass, M; Hirsh, T; Berkovits, D; Stahl, A

    2011-01-01

    The discovery that the neutrino changes flavor as it travels through space has implications for the Standard Model of particle physics (SM)[1]. To know the contribution of neutrinos to the SM, needs precise measurements of the parameters governing the neutrino oscillations. This will require a high intensity beam-based neutrino oscillation facility. The EURONu Design Study will review three currently accepted methods of realizing this facility (the so-called Super-Beams, Beta Beams and Neutrino Factories) and perform a cost assessment that, coupled with the physics performance, will give means to the European research authorities to make a decision on the layout and construction of the future European neutrino oscillation facility. ”Beta Beams” produce collimated pure electron neutrino and antineutrino beams by accelerating beta active ions to high energies and letting them decay in a race-track shaped storage ring. EURONu Beta Beams are based on CERNs infrastructure and the fact that some of the already ...

  7. Evidence for neutrino oscillations in the Sudbury Neutrino Observatory

    Energy Technology Data Exchange (ETDEWEB)

    Marino, Alysia Diane [Univ. of California, Berkeley, CA (United States)

    2004-01-01

    The Sudbury Neutrino Observatory (SNO) is a large-volume heavy water Cerenkov detector designed to resolve the solar neutrino problem. SNO observes charged-current interactions with electron neutrinos, neutral-current interactions with all active neutrinos, and elastic-scattering interactions primarily with electron neutrinos with some sensitivity to other flavors. This dissertation presents an analysis of the solar neutrino flux observed in SNO in the second phase of operation, while ~2 tonnes of salt (NaCl) were dissolved in the heavy water. The dataset here represents 391 live days of data. Only the events above a visible energy threshold of 5.5 MeV and inside a fiducial volume within 550 cm of the center of the detector are studied. The neutrino flux observed via the charged-current interaction is [1.71 ± 0.065(stat.)±$0.065\\atop{0.068}$(sys.)±0.02(theor.)] x 106cm-2s-1, via the elastic-scattering interaction is [2.21±0.22(stat.)±$0.12\\atop{0.11}$(sys.)±0.01(theor.)] x 106cm-2s-1, and via the neutral-current interaction is [5.05±0.23(stat.)±$0.31\\atop{0.37}$(sys.)±0.06(theor.)] x 106cm-2s-1. The electron-only flux seen via the charged-current interaction is more than 7σ below the total active flux seen via the neutral-current interaction, providing strong evidence that neutrinos are undergoing flavor transformation as they travel from the core of the Sun to the Earth. The most likely origin of the flavor transformation is matter-induced flavor oscillation.

  8. Neutrino mixing and lepton CP-phase in neutrino oscillations

    International Nuclear Information System (INIS)

    Ryzhikh, D.A.; Ter-Martirosyan, K.A.

    2001-01-01

    One studied oscillations of the Dirac neutrinos belonging to three generations in vacuum with regard to the effect of the lepton CP-breaking phase on them in the matrix of lepton mixing (analogue of the quark CP-phase). In the general form one obtained formulae for probabilities of transition of neutrino of one kind to another at oscillations depending on three angles of mixing and on CP-phase. It was pointed that when measuring oscillation average probabilities of transition of neutrino of one kind to another one might in principle, restore the value of lepton CP-phase. Manifestation of CP-phase in the form of deviation of the values of probabilities of direct neutrino transition from reverse one is the effect practically escaping observation [ru

  9. Neutrino oscillations and the seesaw origin of neutrino mass

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, O.G., E-mail: omr@fis.cinvestav.mx [Departamento de Física, Centro de Investigación y de Estudios Avanzados del IPN, Apdo. Postal 14-740, 07000 Mexico, Distrito Federal (Mexico); Valle, J.W.F. [AHEP Group, Institut de Física Corpuscular – C.S.I.C./Universitat de València, Parc Cientific de Paterna, C/Catedratico José Beltrán, 2, E-46980 Paterna (València) (Spain)

    2016-07-15

    The historical discovery of neutrino oscillations using solar and atmospheric neutrinos, and subsequent accelerator and reactor studies, has brought neutrino physics to the precision era. We note that CP effects in oscillation phenomena could be difficult to extract in the presence of unitarity violation. As a result upcoming dedicated leptonic CP violation studies should take into account the non-unitarity of the lepton mixing matrix. Restricting non-unitarity will shed light on the seesaw scale, and thereby guide us towards the new physics responsible for neutrino mass generation.

  10. Atmospheric neutrino oscillations for earth tomography

    International Nuclear Information System (INIS)

    Winter, Walter

    2016-01-01

    Modern proposed atmospheric neutrino oscillation experiments, such as PINGU in the Antarctic ice or ORCA in Mediterranean sea water, aim for precision measurements of the oscillation parameters including the ordering of the neutrino masses. They can, however, go far beyond that: Since neutrino oscillations are affected by the coherent forward scattering with matter, neutrinos can provide a new view on the interior of the earth. We show that the proposed atmospheric oscillation experiments can measure the lower mantle density of the earth with a precision at the level of a few percent, including the uncertainties of the oscillation parameters and correlations among different density layers. While the earth's core is, in principle, accessible by the angular resolution, new technology would be required to extract degeneracy-free information.

  11. Neutrino oscillation measurements with reactors

    Energy Technology Data Exchange (ETDEWEB)

    McKeown, R.D. [W. K. Kellogg Radiation Laboratory, California Institute of Technology, Pasadena, CA 91125 (United States)

    2010-11-01

    Since the first direct observations of antineutrino events by Reines and Cowan in the 1950's, nuclear reactors have been an important tool in the study of neutrino properties. More recently, the study of neutrino oscillations has been a very active area of research. The pioneering observation of oscillations by the KamLAND experiment has provided important information on the neutrino masses and the neutrino mixing matrix. New experiments to study the remaining unknown mixing angle are currently under development. These recent studies and potential future developments will be discussed.

  12. Establishing atmospheric neutrino oscillations with Super-Kamiokande

    International Nuclear Information System (INIS)

    Kajita, T.; Kearns, E.; Shiozawa, M.

    2016-01-01

    In this article we review the discovery of atmospheric neutrino oscillation by the Super-Kamiokande experiment. This review outlines the sequence of observations and their associated publications that solved the atmospheric neutrino anomaly and established the existence of neutrino oscillations with nearly maximal mixing of muon neutrinos and tau neutrinos. We also discuss subsequent and ongoing studies that use atmospheric neutrinos to continue to reveal the nature of the neutrino.

  13. Topological phase in two flavor neutrino oscillations

    International Nuclear Information System (INIS)

    Mehta, Poonam

    2009-01-01

    We show that the phase appearing in neutrino flavor oscillation formulae has a geometric and topological contribution. We identify a topological phase appearing in the two flavor neutrino oscillation formula using Pancharatnam's prescription of quantum collapses between nonorthogonal states. Such quantum collapses appear naturally in the expression for appearance and survival probabilities of neutrinos. Our analysis applies to neutrinos propagating in vacuum or through matter. For the minimal case of two flavors with CP conservation, our study shows for the first time that there is a geometric interpretation of the neutrino oscillation formulae for the detection probability of neutrino species.

  14. Long-baseline neutrino oscillation experiments

    International Nuclear Information System (INIS)

    Crane, D.; Goodman, M.

    1994-01-01

    There is no unambiguous definition for long baseline neutrino oscillation experiments. The term is generally used for accelerator neutrino oscillation experiments which are sensitive to Δm 2 2 , and for which the detector is not on the accelerator site. The Snowmass N2L working group met to discuss the issues facing such experiments. The Fermilab Program Advisory Committee adopted several recommendations concerning the Fermilab neutrino program at their Aspen meeting immediately prior to the Snowmass Workshop. This heightened the attention for the proposals to use Fermilab for a long-baseline neutrino experiment at the workshop. The plan for a neutrino oscillation program at Brookhaven was also thoroughly discussed. Opportunities at CERN were considered, particularly the use of detectors at the Gran Sasso laboratory. The idea to build a neutrino beam from KEK towards Superkamiokande was not discussed at the Snowmass meeting, but there has been considerable development of this idea since then. Brookhaven and KEK would use low energy neutrino beams, while FNAL and CERN would plan have medium energy beams. This report will summarize a few topics common to LBL proposals and attempt to give a snapshot of where things stand in this fast developing field

  15. Experimental studies of neutrino oscillations

    CERN Document Server

    Kajita, Takaaki

    2016-01-01

    The 2015 Nobel Prize in physics has been awarded to Takaaki Kajita and Arthur McDonald "for the discovery of neutrino oscillations, which shows that neutrinos have mass". Takaaki Kajita of Tokyo University is a Japanese physicist, known for neutrino experiments at the Kamiokande and its successor, Super-Kamiokande. This volume of collected works of Kajita on neutrino oscillations provides a good glimpse into as well as a record of the rise and the role of Asian research in the frontiers of neutrino physics. Japan is now a major force in the study of the 3 families of neutrinos. Much remains to be done to clarify the Dirac vs. Majorana nature of the neutrino, and the cosmological implications of the neutrino. The collected works of Kajita and his Super-Kamiokande group will leave an indelible foot-print in the history of big and better science.

  16. Energy dependence of solar-neutrino--electron scattering as a test of neutral currents

    International Nuclear Information System (INIS)

    Kwong, W.; Rosen, S.P.

    1992-01-01

    The energy dependence of ν-e scattering of solar neutrinos is investigated in the framework of neutrino oscillations and the nonadiabatic Mikheyev-Smirnov-Wolfenstein effect. It is shown that, with sufficient data, it will be possible to establish unambiguously whether neutrino oscillations are actually occurring and whether the electron neutrino oscillates into active or inactive (sterile) neutrino flavors

  17. Quantum correlations in terms of neutrino oscillation probabilities

    Energy Technology Data Exchange (ETDEWEB)

    Alok, Ashutosh Kumar, E-mail: akalok@iitj.ac.in [Indian Institute of Technology Jodhpur, Jodhpur 342011 (India); Banerjee, Subhashish, E-mail: subhashish@iitj.ac.in [Indian Institute of Technology Jodhpur, Jodhpur 342011 (India); Uma Sankar, S., E-mail: uma@phy.iitb.ac.in [Indian Institute of Technology Bombay, Mumbai 400076 (India)

    2016-08-15

    Neutrino oscillations provide evidence for the mode entanglement of neutrino mass eigenstates in a given flavour eigenstate. Given this mode entanglement, it is pertinent to consider the relation between the oscillation probabilities and other quantum correlations. In this work, we show that all the well-known quantum correlations, such as the Bell's inequality, are directly related to the neutrino oscillation probabilities. The results of the neutrino oscillation experiments, which measure the neutrino survival probability to be less than unity, imply Bell's inequality violation.

  18. Sum rules for neutrino oscillations

    International Nuclear Information System (INIS)

    Kobzarev, I.Yu.; Martemyanov, B.V.; Okun, L.B.; Schepkin, M.G.

    1981-01-01

    Sum rules for neutrino oscillations are obtained. The derivation of the general form of the s matrix for two stage process lsub(i)sup(-)→ν→lsub(k)sup(+-) (where lsub(i)sup(-)e, μ, tau, ... are initial leptons with flavor i and lsub(k)sup(+-) is final lepton) is presented. The consideration of two stage process lsub(i)sup(-)→ν→lsub(k)sup(+-) gives the possibility to take into account neutrino masses and to obtain the expressions for the oscillating cross sections. In the case of Dirac and left-handed Majorana neutrino is obtained the sum rule for the quantities 1/Vsub(K)σ(lsub(i)sup(-)→lsub(K)sup(+-)), (where Vsub(K) is a velocity of lsub(K)). In the left-handed Majorana neutrino case there is an additional antineutrino admixture leading to lsub(i)sup(-)→lsub(K)sup(+) process. Both components (neutrino and antineutrino) oscillate independently. The sums Σsub(K)1/Vsub(k)σ(lsub(i)sup(-) - lsub(K)sup(+-) then oscillate due to the presence of left-handed antineutrinos and right-handed neutrinos which do not take part in weak interactions. If right-handed currents are added sum rules analogous to considered above may be obtained. All conclusions are valid in the general case when CP is not conserved [ru

  19. How neutrino oscillations can induce an effective neutrino number of less than three during big bang nucleosynthesis

    International Nuclear Information System (INIS)

    Foot, R.; Volkas, R.R.

    1997-01-01

    Ordinary-sterile neutrino oscillations can generate significant neutrino asymmetry in the early Universe. In this paper we extend this work by computing the evolution of neutrino asymmetries and light element abundances during the big bang nucleosynthesis (BBN) epoch. We show that a significant electron-neutrino asymmetry can be generated in a way that is approximately independent of the oscillation parameters δm 2 and sin 2 2θ for a range of parameters in an interesting class of models. The numerical value of the asymmetry leads to the prediction that the effective number of neutrino flavors during BBN is either about 2.5 or 3.4, depending on the sign of the asymmetry. Interestingly, one class of primordial deuterium abundance data favors an effective number of neutrino flavors during the epoch of BBN of less than 3. copyright 1997 The American Physical Society

  20. Neutrino oscillations in the Kerr-Newman spacetime

    International Nuclear Information System (INIS)

    Ren Jun; Zhang Chengmin

    2010-01-01

    The mass neutrino oscillation in the Kerr-Newman (K-N) spacetime is studied in the plane θ = θ 0 , and general equations of the oscillation phases are given. The effect of the rotation and electric charge on the phase is presented. Then, we consider three special cases. (1) The neutrinos travel along the geodesics with angular momentum L = aE in the equatorial plane. (2) The neutrinos travel along the geodesics with L = 0 in the equatorial plane. (3) The neutrinos travel along the radial geodesics in the direction θ = 0. Finally, we calculate the proper oscillation length in the K-N spacetime. The effect of the gravitational field on the oscillation length is embodied in the gravitational red shift factor. When the neutrino travels out of the gravitational field, a blue shift of the oscillation length takes place. We discuss the variation of the oscillation length influenced by the gravitational field strength, the rotation a 2 and charge Q.

  1. Neutrino oscillations in discrete-time quantum walk framework

    Energy Technology Data Exchange (ETDEWEB)

    Mallick, Arindam; Mandal, Sanjoy; Chandrashekar, C.M. [C. I. T. Campus, The Institute of Mathematical Sciences, Chennai (India); Homi Bhabha National Institute, Training School Complex, Mumbai (India)

    2017-02-15

    Here we present neutrino oscillation in the framework of quantum walks. Starting from a one spatial dimensional discrete-time quantum walk we present a scheme of evolutions that will simulate neutrino oscillation. The set of quantum walk parameters which is required to reproduce the oscillation probability profile obtained in both, long range and short range neutrino experiment is explicitly presented. Our scheme to simulate three-generation neutrino oscillation from quantum walk evolution operators can be physically realized in any low energy experimental set-up with access to control a single six-level system, a multiparticle three-qubit or a qubit-qutrit system. We also present the entanglement between spins and position space, during neutrino propagation that will quantify the wave function delocalization around instantaneous average position of the neutrino. This work will contribute towards understanding neutrino oscillation in the framework of the quantum information perspective. (orig.)

  2. Subpanel on accelerator-based neutrino oscillation experiments

    International Nuclear Information System (INIS)

    1995-09-01

    Neutrinos are among nature's fundamental constituents, and they are also the ones about which we know least. Their role in the universe is widespread, ranging from the radioactive decay of a single atom to the explosions of supernovae and the formation of ordinary matter. Neutrinos might exhibit a striking property that has not yet been observed. Like the back-and-forth swing of a pendulum, neutrinos can oscillate to-and-from among their three types (or flavors) if nature provides certain conditions. These conditions include neutrinos having mass and a property called open-quotes mixing.close quotes The phenomenon is referred to as neutrino oscillations. The questions of the origin of neutrino mass and mixing among the neutrino flavors are unsolved problems for which the Standard Model of particle physics holds few clues. It is likely that the next critical step in answering these questions will result from the experimental observation of neutrino oscillations. The High Energy Physics Advisory Panel (HEPAP) Subpanel on Accelerator-Based Neutrino Oscillation Experiments was charged to review the status and discovery potential of ongoing and proposed accelerator experiments on neutrino oscillations, to evaluate the opportunities for the U.S. in this area of physics, and to recommend a cost-effective plan for pursuing this physics, as appropriate. The complete charge is provided in Appendix A. The Subpanel studied these issues over several months and reviewed all the relevant and available information on the subject. In particular, the Subpanel reviewed the two proposed neutrino oscillation programs at Fermi National Accelerator Laboratory (Fermilab) and at Brookhaven National Laboratory (BNL). The conclusions of this review are enumerated in detail in Chapter 7 of this report. The recommendations given in Chapter 7 are also reproduced in this summary

  3. Entanglement in neutrino oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Blasone, M.; Dell' Anno, F.; De Siena, S.; Illuminati, F. [Universita degli Studi di Salerno Via Ponte don Melillon, Dipt. di Matematica e Informatica, Fisciano SA (Italy); INFN Sezione di Napoli, Gruppo collegato di Salerno - Baronissi SA (Italy); Dell' Anno, F.; De Siena, S.; Illuminati, F. [CNR-INFM Coherentia - Napoli (Italy); Blasone, M. [ISI Foundation for Scientific Interchange, Torino (Italy)

    2009-03-15

    Flavor oscillations in elementary particle physics are related to multimode 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. (authors)

  4. Entanglement in neutrino oscillations

    International Nuclear Information System (INIS)

    Blasone, M.; Dell'Anno, F.; De Siena, S.; Illuminati, F.; Dell'Anno, F.; De Siena, S.; Illuminati, F.; Blasone, M.

    2009-01-01

    Flavor oscillations in elementary particle physics are related to multimode 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. (authors)

  5. Invariants of collective neutrino oscillations

    International Nuclear Information System (INIS)

    Pehlivan, Y.; Balantekin, A. B.; Kajino, Toshitaka; Yoshida, Takashi

    2011-01-01

    We consider the flavor evolution of a dense neutrino gas by taking into account both vacuum oscillations and self-interactions of neutrinos. We examine the system from a many-body perspective as well as from the point of view of an effective one-body description formulated in terms of the neutrino polarization vectors. We show that, in the single angle approximation, both the many-body picture and the effective one-particle picture possess several constants of motion. We write down these constants of motion explicitly in terms of the neutrino isospin operators for the many-body case and in terms of the polarization vectors for the effective one-body case. The existence of these constants of motion is a direct consequence of the fact that the collective neutrino oscillation Hamiltonian belongs to the class of Gaudin Hamiltonians. This class of Hamiltonians also includes the (reduced) BCS pairing Hamiltonian describing superconductivity. We point out the similarity between the collective neutrino oscillation Hamiltonian and the BCS pairing Hamiltonian. The constants of motion manifest the exact solvability of the system. Borrowing the well established techniques of calculating the exact BCS spectrum, we present exact eigenstates and eigenvalues of both the many-body and the effective one-particle Hamiltonians describing the collective neutrino oscillations. For the effective one-body case, we show that spectral splits of neutrinos can be understood in terms of the adiabatic evolution of some quasiparticle degrees of freedom from a high-density region where they coincide with flavor eigenstates to the vacuum where they coincide with mass eigenstates. We write down the most general consistency equations which should be satisfied by the effective one-body eigenstates and show that they reduce to the spectral split consistency equations for the appropriate initial conditions.

  6. Parametric resonance in neutrino oscillations in matter

    Indian Academy of Sciences (India)

    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 ...

  7. Oscillating neutrinos from the Galactic center

    International Nuclear Information System (INIS)

    Crocker, R.M.; Volkas, R.R.; Melia, F.

    1999-11-01

    It has recently been demonstrated that the γ-ray emission spectrum of the EGRET-identified, central Galactic source 2EG J1746-2852 can be well fitted by positing that these photons are generated by the decay of π 0, s produced in p-p scattering at or near an energizing shock. Such scattering also produces charged pions which decay leptonically. The ratio of γ-rays to neutrinos generated by the central Galactic source may be accurately determined and a well-defined and potentially-measurable high energy neutrino flux at Earth is unavoidable. An opportunity, therefore, to detect neutrino oscillations over an unprecedented scale is offered by this source. In this paper we assess the prospects for such an observation with the generation of neutrino Cerenkov telescopes now in the planning stage. We determine that the next generation of detectors may find an oscillation signature in the Galactic Center (GC) signal, but that such an observation will probably not further constrain the oscillation parameter space mapped out by current atmospheric, solar, reactor and accelerator neutrino oscillation experiments

  8. Effects of neutrino oscillation on supernova neutrino. Inverted mass hierarchy

    International Nuclear Information System (INIS)

    Takahashi, Keitaro; Sato, Katsuhiko

    2003-01-01

    We study the effects of neutrino oscillation on supernova neutrinos in the case of the inverted mass hierarchy (m 3 1 2 ) as well as the normal mass hierarchy (m 1 2 3 ). Numerical analysis using realistic supernova and presupernova models allows us to investigate quantitatively the possibility to probe neutrino oscillation parameters. We show that information about the mass hierarchy can be obtained if θ 13 is rather large (sin 2 2θ 13 > 10 -3 ) and that θ 13 can be probed effectively by SuperKamiokande if the neutrino mass hierarchy is inverted. Errors due to the uncertainty in the original neutrino spectra and the Earth effect are also discussed. (author)

  9. Neutrino oscillations and a new Faraday effect

    International Nuclear Information System (INIS)

    Anwar Mughal, M.; Ahmed, K.

    1992-07-01

    By analogy with the classical Faraday effect for the electromagnetic waves, a Faraday effect for massive neutrinos is found to be a somewhat generic description of neutrino oscillations when the neutrinos traverse a dense medium with or without a magnetic field. We further plot the Faraday angle for the solar neutrino problem as an illustration of the fact that the Faraday effect may yield a conceptually convenient parametrization of various neutrino oscillation scenarios. (author). 8 refs, 3 figs

  10. Robust signatures of solar neutrino oscillation solutions

    CERN Document Server

    Bahcall, J N; Peña-Garay, C; Bahcall, John N.; Peña-Garay, Carlos

    2002-01-01

    With the goal of identifying signatures that select specific neutrino oscillation parameters, we test the robustness of global oscillation solutions that fit all the available solar and reactor experimental data. We use three global analysis strategies previously applied by different authors and also determine the sensitivity of the oscillation solutions to the critical nuclear fusion cross section, S_{17}(0), for the production of 8B. The neutral current to charged current ratio for SNO is predicted to be 3.5 +- 0.6 (1 sigma) for the favored LMA, LOW, and VAC solutions, which is separated from the no-oscillation value of 1.0 by much more than the expected experimental error. The predicted range of the day-night difference in charged current rates is between 0% and 21% (3 sigma) and is to be strongly correlated with the day-night effect for neutrino-electron scattering. A measurement by SNO of either a NC to CC ratio > 3.3 or a day-night difference > 10%, would favor a small region of the currently allowed LM...

  11. Lepton asymmetry and neutrino oscillations interplay

    Energy Technology Data Exchange (ETDEWEB)

    Kirilova, Daniela, E-mail: dani@astro.bas.bg [Bulgarian Academy of Sciences, Institute of Astronomy and NAO (Bulgaria)

    2013-03-15

    We discuss the interplay between lepton asymmetry L and {nu} oscillations in the early Universe. Neutrino oscillations may suppress or enhance previously existing L. On the other hand L is capable to suppress or enhance neutrino oscillations. The mechanism of L enhancement in MSW resonant {nu} oscillations in the early Universe is numerically analyzed. L cosmological effects through {nu} oscillations are discussed. We discuss how L may change the cosmological BBN constraints on neutrino and show that BBN model with {nu}{sub e}{r_reversible}{nu}{sub s} oscillations is extremely sensitive to L - it allows to obtain the most stringent constraints on L value. We discuss also the cosmological role of active-sterile {nu} mixing and L in connection with the indications about additional relativistic density in the early Universe, pointed out by BBN, CMB and LSS data and the analysis of global {nu} data.

  12. Massive neutrinos flavor mixing of leptons and neutrino oscillations

    CERN Document Server

    2015-01-01

    Since the discovery of neutrino oscillations neutrino physics has become an interesting field of research in physics. They imply that neutrino must have a small mass and that the neutrinos, coupled to the charged leptons, are mixtures of the mass eigenstates, analogous to the flavor mixing of the quarks. The mixing angles for the quarks are small, but for the leptons two of the mixing angles are large. The masses of the three neutrinos must be very small, less than 1 eV, but from the oscillation experiments we only know the mass differences — the absolute masses are still unknown. Also we do not know, if the masses of the neutrinos are Dirac masses, as the masses of the charged leptons and of the quarks, or whether they are Majorana masses. In this volume, an overview of the present state of research in neutrino physics is given by well-known experimentalists and theorists. The contents — originated from talks and discussions at a recent conference addressing some of the most pressing open questions in n...

  13. Analytic Neutrino Oscillation Probabilities in Matter: Revisited

    Energy Technology Data Exchange (ETDEWEB)

    Parke, Stephen J. [Fermilab; Denton, Peter B. [Copenhagen U.; Minakata, Hisakazu [Madrid, IFT

    2018-01-02

    We summarize our recent paper on neutrino oscillation probabilities in matter, explaining the importance, relevance and need for simple, highly accurate approximations to the neutrino oscillation probabilities in matter.

  14. On oscillations of neutrinos with Dirac and Majorana masses

    International Nuclear Information System (INIS)

    Bilenky, S.M.; Hosek, J.; Petcov, S.T.; Bylgarska Akademiya na Naukite, Sofia)

    1980-01-01

    Pontecorvo neutrino beam oscillations are discussed assuming both Dirac and Majorana neutrino mass terms. It is proved that none of possible experiments on neutrino oscillations, including those on effects of CP violation, can distinguish between these two possibilities. Neutrino oscillations with concomitant Dirac and Majorana mass terms are also considered

  15. Collective neutrino oscillations and r-process nucleosynthesis in supernovae

    Science.gov (United States)

    Duan, Huaiyu

    2012-10-01

    Neutrinos can oscillate collectively in a core-collapse supernova. This phenomenon can occur much deeper inside the supernova envelope than what is predicted from the conventional matter-induced Mikheyev-Smirnov-Wolfenstein effect, and hence may have an impact on nucleosynthesis. The oscillation patterns and the r-process yields are sensitive to the details of the emitted neutrino fluxes, the sign of the neutrino mass hierarchy, the modeling of neutrino oscillations and the astrophysical conditions. The effects of collective neutrino oscillations on the r-process will be illustrated using representative late-time neutrino spectra and outflow models.

  16. Search on neutrino oscillation νμ→νe in the NOMAD experiment

    International Nuclear Information System (INIS)

    Valuev, Viatcheslav

    1998-01-01

    The NOMAD experiment is a search for neutrino oscillations using the large band neutrino beams of SPS at CERN. It is dealing with the two oscillation modes: ν μ →ν τ and ν μ →ν e . This thesis presents the results obtained in the search of oscillations ν μ →ν e with the data produced by NOMAD in 1995 and 1996. The first two chapters deal with the short presentation of the neutrino oscillation phenomenology and a summary of the experimental situation. The third chapter describes the experimental setup of the NOMAD detector at CERN, designed to identify the interactions of ν e by means of the charged current. This is done with the transition radiation detector (TRD) designed to separate the electrons from pions with a rejection factor higher then 1000 at an electron efficiency of 90%, in the 1 - 50 GeV region. Details about the TRD operation are given in chapter four. The fifth chapter gives the algorithms of electron-pion separation as well as their performances. The last two chapters present the analysis of the ν μ →ν e data obtained in 1995 and 1996 and the final results. The conclusion is that the available data give no evidence for the neutrino oscillations. The upper limit obtained for the mixing angle is sin 2 (2θ) -3 (90% C.L.). This result eliminates completely the oscillation region of LSND experiment (Liquid Scintillator Neutrino Detector) at LAMPF for Δm 2 > 15 eV 2 and gives the most constraining world limit on sin 2 (2θ) for Δm 2 > 20 eV 2

  17. Some unsettled questions in the problem of neutrino oscillations

    International Nuclear Information System (INIS)

    Beshtoev, Kh.M.

    2003-01-01

    It is noted that the theory of neutrino oscillations can be constructed only in the framework of the particle physics theory where a mass shell conception is presented and then transitions (oscillations) between neutrinos with equal masses are real and between neutrinos with different masses are virtual. There can be three types of neutrino transitions. In the experiments it is necessary to decide the question: which type of neutrino transitions is realized in nature? At present it is supposed that Dirac and Majorana neutrino oscillations can be realized. It is shown that we cannot put Majorana neutrinos in the standard weak interaction theory without violation of the gauge invariance. If we use the Majorana neutrinos then we come to contradiction with the existing experimental data. Then it is obvious that there can be only realized transitions between Dirac neutrinos with different flavors. It is also 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 in experiments we see neutrino oscillations, indeed only transitions between neutrinos are registered.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 at registrations of sun neutrinos. The analysis shows that the SNO experimental results do not confirm smallness of ν e → ν τ transition angle mixing, which was obtained in the CHOOZ experiment. It is also noted that there is contradiction between the SNO, Super-Kamiokande, Homestake and SAGE, and GNO (GALLEX) data. (author)

  18. Neutrinos from WIMP annihilations in the Sun including neutrino oscillations

    International Nuclear Information System (INIS)

    Blennow, Mattias; Edsjö, Joakim; Ohlsson, Tommy

    2011-01-01

    The prospects to detect neutrinos from the Sun arising from dark matter annihilations in the core of the Sun are reviewed. Emphasis is placed on new work investigating the effects of neutrino oscillations on the expected neutrino fluxes.

  19. Neutrinos from WIMP annihilations in the Sun including neutrino oscillations

    International Nuclear Information System (INIS)

    Blennow, Mattias; Edsjoe, Joakim; Ohlsson, Tommy

    2006-01-01

    The prospects for detecting neutrinos from the Sun arising from dark matter annihilations in the core of the Sun are reviewed. Emphasis is placed on new work investigating the effects of neutrino oscillations on the expected neutrino fluxes

  20. Indication of Electron Neutrino Appearance in the T2K experiment and its long-term implications

    CERN Multimedia

    CERN. Geneva

    2011-01-01

    T2K (Tokai-to-Kamioka) is a long-baseline neutrino oscillation experiment primarily searching for oscillations of muon neutrinos into electron neutrinos. T2K will also make precise measurements of the atmospheric oscillation parameters via muon neutrino disappearance. The experiment uses 30 GeV protons from the new J-PARC Main Ring accelerator, located in Tokai, Japan, to generate a conventional neutrino beam to the Super-Kamiokande far detector. The hadron production measurements of the NA61 experiment at CERN were used to predict the neutrino fluxes at the near and far detectors. The T2K oscillation analysis compares the rates of observed and predicted muon and electron neutrino candidates in the far detector. We present first results based on data accumulated from January 2010 to March 2011. Six electron neutrino events pass the selection criteria for electron appearance at Super-Kamiokande, whereas the expected number of background events is 1.5±0.3. The probability of a fluctuation of the back...

  1. Neutrino oscillations in strong magnetic fields

    International Nuclear Information System (INIS)

    Likhachev, G.G.; Studenikin, A.I.

    1994-07-01

    Neutrino conversion processes between two neutrino species and the corresponding oscillations induced by strong magnetic fields are considered. The value of the critical strength of magnetic field B cr as a function of characteristics of neutrinos in vacuum (Δm 2 ν , mixing angle θ), effective particle density of matter n eff , neutrino (transition) magnetic moment μ-tilde and energy E is introduced. It is shown that the neutrino conversion and oscillations effects induced by magnetic fields B ≥ B cr are important and may result in the depletion of the initial type of ν's in the bunch. A possible increase of these effects in the case when neutrinos pass through a sudden decrease of density of matter (''cross-boundary effect'') and applications to neutrinos from neutron stars and supernova are discussed. (author). 25 refs

  2. A search for matter enhanced neutrino oscillations through measurements of day and night solar neutrino fluxes at the Sudbury Neutrino Observatory

    Science.gov (United States)

    Miknaitis, Kathryn Kelly Schaffer

    The Sudbury Neutrino Observatory (SNO) is a heavy-water Cherenkov detector designed to study 8B neutrinos from the sun. Through the charged-current (CC) and neutral-current (NC) reactions of neutrinos on deuterium, SNO separately determines the flux of electron neutrinos and the flux of all active flavors of solar 8B neutrinos. SNO is also sensitive to the elastic scattering (ES) of neutrinos on electrons in the heavy water. Measurements of the CC and NC rates in SNO have conclusively demonstrated solar neutrino flavor change. This flavor change is believed to be caused by matter-enhanced oscillations in the sun, through the Mikheyev-Smirnov-Wolfenstein (MSW) effect. Matter effects could also change the flavor composition of neutrinos that traverse the earth. A comparison of the day and night measured CC flux at SNO directly tests for the MSW effect and contributes to constraints on neutrino oscillation parameters in the MSW model. We perform measurements of the day and night neutrino fluxes using data from the second phase of SNO, in which salt (NaCl) was added to the heavy water to enhance sensitivity to the NC reaction. Better discrimination between CC and NC events in the salt phase allows the fluxes to be determined without constraining the neutrino energy spectrum. The day-night asymmetry in the CC flux measured in this model-independent analysis is ACC = [-5.6 +/- 7.4(stat.) +/- 5.3(syst.)]%, where the asymmetry is defined as the difference between the night and day values divided by their average. The asymmetries in the NC and ES fluxes are ANC = [4.2 +/- 8.6(stat.) +/- 7.2(syst.)]%, and AES = (14.6 +/- 19.8(stat.) +/- 3.3(syst.)]%. The neutral current asymmetry is expected to be zero assuming standard neutrino oscillations. When we constrain it to be zero, we obtain ACC = [-3.7 +/- 6.3(stat.) +/- 3.2(syst.)]% and AES = [15.3 +/- 19.8(stat.) +/- 3.0(syst.)]%. The day and night energy spectra from the CC reaction have been measured and show no evidence for

  3. Neutrino oscillations in Gallium and reactor experiments and cosmological effects of a light sterile neutrino

    International Nuclear Information System (INIS)

    Acero-Ortega, Mario Andres

    2009-01-01

    Neutrino oscillations is a very well studied phenomenon and the observations from Solar, very-long-baseline Reactor, Atmospheric and Accelerator neutrino oscillation experiments give very robust evidence of three-neutrino mixing. On the other hand, some experimental data have shown anomalies that could be interpreted as indication of exotic neutrino physics beyond three-neutrino mixing. Furthermore, from a cosmological point of view, the possibility of extra light species contributing as a subdominant hot (or warm) component of the Universe is still interesting. In the first part of this Thesis, we focused on the anomaly observed in the Gallium radioactive source experiments. These experiments were done to test the Gallium solar neutrino detectors GALLEX and SAGE, by measuring the electron neutrino flux produced by intense artificial radioactive sources placed inside the detectors. The measured number of events was smaller than the expected one. We interpreted this anomaly as a possible indication of the disappearance of electron neutrinos and, in the effective framework of two-neutrino mixing, we obtained sin 2 2θ ≥ 0.03 and Δm 2 ≥ 0.1 eV 2 . We also studied the compatibility of this result with the data of the Bugey and Chooz reactor antineutrino disappearance experiments. We found that the Bugey data present a hint of neutrino oscillations with 0.02 ≤ sin 2 2θ ≤ 0.07 and Δm 2 ≅ 1.95 eV 2 , which is compatible with the Gallium allowed region of the mixing parameters. Then, combining the data of Bugey and Chooz, the data of Gallium and Bugey, and the data of Gallium, Bugey and Chooz, we found that this hint persists, with an acceptable compatibility of the experimental data. Furthermore, we analyzed the experimental data of the I.L.L., S.R.S, and Gosgen nuclear Reactor experiments. We obtained a good fit of the I.L.L. data, showing 1 and 2σ allowed regions in the oscillation parameters space. However, the combination of I.L.L. data with the Bugey

  4. LOS ALAMOS: Candidate events in a search for neutrino oscillations

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    In the past several years, a number of experiments have searched for neutrino oscillations,where a neutrino of one type (say muon-antineutrinos) spontaneously transforms into a neutrino of another type (say electron antineutrinos). For this phenomenon to occur, neutrinos must be massive and the apparent conservation law of lepton families must be violated. At this time, there is no broadly accepted evidence for neutrino oscillations from a terrestrial experiment. The Liquid Scintillator Neutrino Detector (LSND) experiment (July 1993, page 10) at the Los Alamos Meson Physics facility (LAMPF) is designed to search with high sensitivity for muon-antineutrino electronantineutrino oscillations from positive muon decay at rest. The collaboration consists of groups from the University of California at Riverside, San Diego and Santa Barbara, the University California Intercampus Institute for Research at Particle Accelerators, Embry Riddle Aeronautical University, Linfield College, Los Alamos National Laboratory, Louisiana State University, Louisiana Tech University, the University of New Mexico, Southern University, and Temple University. LAMPF is an intense source of low energy neutrinos due to its 1 mA proton intensity and 800 MeV energy. The neutrino source is well understood because almost all neutrinos arise from positive pion or muon decay; negative muons and pions are readily captured in the iron of the shielding and copper of the beam stop. The production of kaons and heavier mesons is negligible at these energies. The electron-antineutrino rate is calculated to be only 4 x 10 -4 that of muon-antineutrinos in the neutrino energy range between 36 and 52.8 MeV, so that the observation of a significant electronantineutrino rate would be evidence for muon-antineutrino electronantineutrino oscillations. The LSND detector consists of an approximately cylindrical tank 8.3 m long by 5.7 m in diameter. The centre of the detector is 30 m from the neutrino source. On the

  5. Flavor Oscillations in the Supernova Hot Bubble Region: Nonlinear Effects of Neutrino Background

    Science.gov (United States)

    Pastor, Sergio; Raffelt, Georg

    2002-10-01

    The neutrino flux close to a supernova core contributes substantially to neutrino refraction so that flavor oscillations become a nonlinear phenomenon. One unexpected consequence is efficient flavor transformation for antineutrinos in a region where only neutrinos encounter a Mikheyev-Smirnov-Wolfenstein resonance or vice versa. Contrary to previous studies we find that in the neutrino-driven wind the electron fraction Ye always stays below 0.5, corresponding to a neutron-rich environment as required by r-process nucleosynthesis. The relevant range of masses and mixing angles includes the region indicated by LSND, but not the atmospheric or solar oscillation parameters.

  6. Extrinsic CPT violation in neutrino oscillations in matter

    International Nuclear Information System (INIS)

    Jacobson, Magnus; Ohlsson, Tommy

    2004-01-01

    We investigate matter-induced (or extrinsic) CPT violation effects in neutrino oscillations in matter. Especially, we present approximate analytical formulas for the CPT-violating probability differences for three flavor neutrino oscillations in matter with an arbitrary matter density profile. Note that we assume that the CPT invariance theorem holds, which means that the CPT violation effects arise entirely because of the presence of matter. As special cases of matter density profiles, we consider constant and step-function matter density profiles, which are relevant for neutrino oscillation physics in accelerator and reactor long baseline experiments as well as neutrino factories. Finally, the implications of extrinsic CPT violation on neutrino oscillations in matter for several past, present, and future long baseline experiments are estimated

  7. Matter effects in neutrino oscillations

    International Nuclear Information System (INIS)

    Dass, G.V.

    1989-01-01

    After a review of the relevant aspects of neutrino oscillations for propagation in vacuum and in material media, this paper discuss the Mikheyev-Smirnov-Wolfenstein mechanism and its application to a solution of the solar neutrino puzzle. The elementary level of the talk is suitable to people not working in neutrino physics

  8. Limits on neutrino oscillations in the CNGS neutrino beam and event classification with the OPERA detector

    International Nuclear Information System (INIS)

    Ferber, Torben

    2012-09-01

    OPERA, the oscillation project with emulsion-tracking apparatus, is a long-baseline neutrino oscillation experiment. It combines an almost pure, high-energy ν μ beam produced at the SPS accelerator at CERN, Switzerland, with the OPERA neutrino detector located at a distance of about 730 km in the LNGS underground laboratory in Italy. By using a lead/photo emulsion target, ν τ charged current (CC) interactions of ν τ from ν μ → ν τ oscillations can be observed on an event-by-event basis with very low background rates. Within this thesis, a ν μ →ν μ disappearance search is described that uses a flux normalization. independent measurement of the CC event fraction as a function of the hadronic energy as measured by the electronic detectors of OPERA. This allows to derive limits on ν μ →ν μ oscillations, complementary to the main ν τ appearance analysis. For maximal mixing, vertical stroke Δm 2 23 vertical stroke >4.4 x 10 -3 eV 2 is excluded at 90% C.L. by the disappearance analysis. This thesis represents the first application of this method, including systematic uncertainties, in a long-baseline neutrino oscillation experiment.

  9. Analytic treatments of matter-enhanced solar-neutrino oscillations

    International Nuclear Information System (INIS)

    Haxton, W.C.

    1987-01-01

    Mikheyev and Smirnov have pointed out that flavor oscillations of solar neutrinos could be greatly enhanced. The Mikheyev-Smirnov-Wolfenstein mechanism depends on the effective electron neutrino mass that arises from charged-current scattering off solar electrons, a phenomenon first discussed by Wolfenstein. Two analytic treatments, the adiabatic approximation and Landau-Zener (LZ) approximation, have been used in studies of this mechanism. I discuss a simple extension of the LZ approximation that merges naturally with the adiabatic approximation and is free of certain troublesome pathologies that arise in the conventional treatment. In this extension the solar density is approximated as in the conventional treatment, except that the starting and ending densities are the physical ones. Results of this finite LZ approximation are compared to those from the standard LZ approximation, the adiabatic approximation, and ''exact'' numerical integrations. The new approximation is virtually exact regardless of the point of origin of the neutrino in the solar core. This approximation is used to efficiently calculate the solar-neutrino capture rates for /sup 37/Cl, /sup 71/Ga, and /sup 98/Mo. The spatial extent of the solar core, the contributions of minor neutrino species, and the effects of 8 B neutrino capture to excited nuclear states are treated with care. Limits imposed on δm 2 and sin 2 2theta/sub v/ by the nonzero /sup 37/Cl capture rate are derived by considering the expected uncertainties in standard-solar-model flux estimates. Those oscillation parameters are determined that could account for the /sup 37/Cl puzzle and yet lead to a /sup 71/Ga counting rate above the minimum astronomical value

  10. Search on neutrino oscillation {nu}{sub {mu}}{yields}{nu}{sub e} in the NOMAD experiment; Recherches des oscillations de neutrinos {nu}{sub {mu}}{yields}{nu}{sub e} dans l`experience NOMAD

    Energy Technology Data Exchange (ETDEWEB)

    Valuev, Viatcheslav [Paris-7 Univ., 75 (France)

    1998-07-07

    The NOMAD experiment is a search for neutrino oscillations using the large band neutrino beams of SPS at CERN. It is dealing with the two oscillation modes: {nu}{sub {mu}}{yields}{nu}{sub {tau}} and {nu}{sub {mu}}{yields}{nu}{sub e}. This thesis presents the results obtained in the search of oscillations {nu}{sub {mu}}{yields}{nu}{sub e} with the data produced by NOMAD in 1995 and 1996. The first two chapters deal with the short presentation of the neutrino oscillation phenomenology and a summary of the experimental situation. The third chapter describes the experimental setup of the NOMAD detector at CERN, designed to identify the interactions of {nu}{sub e} by means of the charged current. This is done with the transition radiation detector (TRD) designed to separate the electrons from pions with a rejection factor higher then 1000 at an electron efficiency of 90%, in the 1 - 50 GeV region. Details about the TRD operation are given in chapter four. The fifth chapter gives the algorithms of electron-pion separation as well as their performances. The last two chapters present the analysis of the {nu}{sub {mu}}{yields}{nu}{sub e} data obtained in 1995 and 1996 and the final results. The conclusion is that the available data give no evidence for the neutrino oscillations. The upper limit obtained for the mixing angle is sin{sup 2}(2{theta}) < 1.3 {center_dot} 10{sup -3} (90% C.L.). This result eliminates completely the oscillation region of LSND experiment (Liquid Scintillator Neutrino Detector) at LAMPF for {Delta}m{sup 2} > 15 eV{sup 2} and gives the most constraining world limit on sin{sup 2}(2{theta}) for {Delta}m{sup 2} > 20 eV{sup 2} 123 refs., 82 figs., 37 tabs.

  11. Neutrino Oscillation Experiments with J-PARC: T2K, T2K-II and Hyper-Kamiokande

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    The T2K experiment started the operation in 2010, and advances neutrino physics with the discovery of electron neutrino appearance in the muon neutrino beam and precision measurements of neutrino oscillation parameters. In 2016, the measurements of anti-neutrino oscillation directly constrain CP violation in neutrino oscillation. In this colloquium, we introduce many physics results from T2K including the most recent one of the CP violation. By utilizing the J-PARC neutrino beam, the upgrade of the T2K experiment (naming T2K-II) is planned and Hyper-Kamiokande is proposed to explore neutrino physics further. In T2K-II, the beam power of J-PARC will be upgraded to 1.3 MW around 2020. Hyper-Kamiokande is the larger Water Cherenkov detector of 520 k...

  12. Invariant box-parameterization of neutrino oscillations

    International Nuclear Information System (INIS)

    Weiler, Thomas J.; Wagner, DJ

    1998-01-01

    The model-independent 'box' parameterization of neutrino oscillations is examined. The invariant boxes are the classical amplitudes of the individual oscillating terms. Being observables, the boxes are independent of the choice of parameterization of the mixing matrix. Emphasis is placed on the relations among the box parameters due to mixing-matrix unitarity, and on the reduction of the number of boxes to the minimum basis set. 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. General analyses of neutrino oscillations among n≥3 flavors can readily determine the boxes, which can then be manipulated to yield magnitudes of mixing matrix elements

  13. Neutrino-oscillation search with cosmic-ray neutrinos

    International Nuclear Information System (INIS)

    Ayres, D.S.; Cortez, B.; Gaisser, T.K.; Mann, A.K.; Shrock, R.E.; Sulak, L.R.

    1984-01-01

    A sensitive search for neutrino oscillations involving ν/sub e/, ν/sub μ/, and ν/sub tau/ may be provided by measurements of the ratio of the total interaction rates of upward- and downward-going cosmic-ray neutrinos within a massive (approx.10 kton) detector. Assuming mixing between all pairs of ν/sub e/, ν/sub μ/, and ν/sub tau/, the experiment is capable of observing time-averaged probabilities /sub t/ and /sub t/ of magnitude set by mixing strengths corresponding to, e.g., the d- to s-quark mixing strength, and of reaching the limit Δm/sub i/j 2 equivalentVertical Barm/sub i/ 2 -m/sub j/ 2 Vertical Barroughly-equal10 -4 eV 2 , where m/sub i/, and m/sub j/ are neutrino mass eigenstates, and P/sub e/tau and P/sub mutau/ are the probabilities for ν/sub e/ and ν/sub μ/, respectively, to oscillate into ν/sub tau/ after traversing a distance Lroughly-equal diameter of the Earth. Possible ambiguities may be resolved through comparison of the ratios N/sub e//N/sub μ/ for the upward- and downward-going neutrinos

  14. Matter oscillations and solar neutrinos: A review of the MSW [Mikheyev-Smirnov-Wolfenstein] effect

    International Nuclear Information System (INIS)

    Rosen, S.P.; Gelb, J.M.

    1986-01-01

    We review the theory of the Mikheyev-Smirnov-Wolfenstein effect, in which matter oscillations can greatly enhance ''in vacuo'' neutrino oscillations, and we examine its consequences for the solar neutrino problem. Using a two-flavor model, we discuss the solutions in the Δm 2 -sin 2 2Θ parameter space for the 37 Cl experiment, and describe their predictions for the 71 Ga experiment and for the spectrum of electron-neutrinos arriving at earth. We also comment on the three-flavor case

  15. Cosmological nucleosynthesis and active-sterile neutrino oscillations with small mass differences: the nonresonant case

    International Nuclear Information System (INIS)

    Kirilova, D.P.; Chizhov, M.V.

    1998-05-01

    We study the nonresonant oscillations between left-handed electron neutrinos ν s and nonthermalized sterile neutrinos ν s in the early Universe plasma. The case when ν s do not thermalize till 2 MeV and the oscillations become effective after ν e decoupling is discussed. As far as for this model the rates of expansion of the Universe, neutrino oscillations and neutrino interactions with the medium may be comparable, we have analyzed the kinetic equations for neutrino density matrix, accounting simultaneously for these processes. The evolution of neutrino ensembles was described numerically by integrating the kinetic equations for the neutrino density matrix in momentum space for small mass differences δm 2 ≤10 -7 eV 2 . This approach allowed us to study precisely the evolution of the neutrino number densities, energy spectrum distortion and the asymmetry between neutrinos and antineutrinos due to oscillations for each momentum mode. We have performed a complete numerical analysis for the full range of the oscillations parameters of the model of the influence of the nonequilibrium ν e ↔ν s oscillations on the primordial production of 4 He. The exact kinetic approach enabled us to calculate the effects of neutrino population depletion, the distortion of the neutrino spectrum and the generation of neutrino-antineutrino asymmetry on the kinetics of neutron-to-proton transitions during the primordial nucleosynthesis epoch and correspondingly on the cosmological 4 He production. It was shown that the neutrino population depletion and spectrum distortion play an important role. The asymmetry effect, in case the lepton asymmetry is accepted initially equal to the baryon one, is proved to be negligible for the discussed range of δm 2 . Constant helium contours in δm 2 -θ plane were calculated. Thanks to the exact kinetic approach more precise cosmological constraints on the mixing parameters were obtained. (author)

  16. Measurement of Atmospheric Neutrino Oscillations with Very Large Volume Neutrino Telescopes

    Directory of Open Access Journals (Sweden)

    J. P. Yáñez

    2015-01-01

    Full Text Available Neutrino oscillations have been probed during the last few decades using multiple neutrino sources and experimental set-ups. In the recent years, very large volume neutrino telescopes have started contributing to the field. First ANTARES and then IceCube have relied on large and sparsely instrumented volumes to observe atmospheric neutrinos for combinations of baselines and energies inaccessible to other experiments. Using this advantage, the latest result from IceCube starts approaching the precision of other established technologies and is paving the way for future detectors, such as ORCA and PINGU. These new projects seek to provide better measurements of neutrino oscillation parameters and eventually determine the neutrino mass ordering. The results from running experiments and the potential from proposed projects are discussed in this review, emphasizing the experimental challenges involved in the measurements.

  17. Apparent CPT violation in neutrino oscillation experiments

    International Nuclear Information System (INIS)

    Engelhardt, Netta; Nelson, Ann E.; Walsh, Jonathan R.

    2010-01-01

    We consider searching for light sterile fermions and new forces by using long baseline oscillations of neutrinos and antineutrinos. A new light sterile state and/or a new force can lead to apparent CPT violation in muon neutrino and antineutrino oscillations. As an example, we present an economical model of neutrino masses containing a sterile neutrino. The potential from the standard model weak neutral current gives rise to a difference between the disappearance probabilities of neutrinos and antineutrinos, when mixing with a light sterile neutrino is considered. The addition of a B-L interaction adds coherently to the neutrino current potential and increases the difference between neutrino and antineutrino disappearance. We find that this model can improve the fit to the results of MINOS for both neutrinos and antineutrinos, without any CPT violation, and that the regions of parameter space which improve the fit are within experimental constraints.

  18. Neutrino oscillations with the OPERA experiment

    CERN Document Server

    Galati, Giuliana

    2016-01-01

    OPERA (Oscillation Project with Emulsion tRacking Apparatus) was a long-baseline experiment at the Gran Sasso laboratory (LNGS) designed to search for ν μ → ν τ oscillations in appearance mode. OPERA took data from 2008 to 2012 with the CNGS neutrino beam from CERN. The observation of five ν τ candidates allowed assessing the discovery of ν μ → ν τ appearance in the CNGS neutrino beam with a significance of 5 . 1 σ . The data analysis is still ongoing, with the goal of improving the sensitivity to the sterile neutrino search in the ν μ → ν τ and ν μ → ν e appearance channels and oscillation parameters with reduced statistical uncertainties. Current results will be presented and perspectives discussed.

  19. Invariant box parameterization of neutrino oscillations

    International Nuclear Information System (INIS)

    Weiler, T.J.; Wagner, D.

    1998-01-01

    The model-independent 'box' parameterization of neutrino oscillations is examined. The invariant boxes are the classical amplitudes of the individual oscillating terms. Being observables, the boxes are independent of the choice of parameterization of the mixing matrix. Emphasis is placed on the relations among the box parameters due to mixing matrix unitarity, and on the reduction of the number of boxes to the minimum basis set. 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. General analyses of neutrino oscillations among n≥3 flavors can readily determine the boxes, which can then be manipulated to yield magnitudes of mixing matrix elements. copyright 1998 American Institute of Physics

  20. Experimental search for muon-neutrino oscillations and analysis of the simultaneous mixing of three neutrino flavors

    International Nuclear Information System (INIS)

    Bluemer, J.

    1985-01-01

    In the present thesis the experiment of the CDHS collaboration on the search for inclusive muon-neutrino oscillations is described. The event rates of ν μ reactions via charged currents was simultaneously measured in two detectors which were 130 m and 885 m away from the beam origin. The data contain no hints for oscillation effects. At maximal mixing mass differences of the contributing eigenstates are excluded in a range 0.26 ≤ Δm 2 ≤ 90 eV 2 with 90% confidence. The best sensitivity was reached for Δm 2 =2.5 eV 2 and allows there a maximal mixing parameter sin 2 2 ≤ 0.053. From the CDHS data the hitherto best limits on oscillation parameters resulted. From a common analysis of different oscillation experiments the allowed parameters for the case of simultaneous transitions between electron, muon, and tau neutrinos could be obtained. Regarding systematic uncertainties also here no evidence for oscillations exists. (orig./HSI) [de

  1. Study on the Neutrino Oscillation with a Next Generation Medium-Baseline Reactor Experiment

    International Nuclear Information System (INIS)

    Joo, Kyung Kwang; Shin, Chang Dong

    2014-01-01

    For over fifty years, reactor experiments have played an important role in neutrino physics, in both discoveries and precision measurements. One of the methods to verify the existence of neutrino is the observation of neutrino oscillation phenomena. Electron antineutrinos emitted from a reactor provide the measurement of the small mixing angle θ 13 , providing rich programs of neutrino properties, detector development, nuclear monitoring, and application. Using reactor neutrinos, future reactor neutrino experiments, more precise measurements of θ 12 ,Δm 12 2 , and mass hierarchy will be explored. The precise measurement of θ 13 would be crucial for measuring the CP violation parameters at accelerators. Therefore, reactor neutrino physics will assist in the complete understanding of the fundamental nature and implications of neutrino masses and mixing. In this paper, we investigated several characteristics of RENO-50, which is a future medium-baseline reactor neutrino oscillation experiment, by using the GloBES simulation package

  2. Neutrino oscillations in the Earth suggest a terrestrial test of solution to solar neutrino problem

    International Nuclear Information System (INIS)

    Dar, A.; Mann, A.; Technicon-Israel Inst. of Tech., Haifa. Space Research Inst.)

    1987-01-01

    The verification of the Mikheyev-Smirnov-Wolfenstein (MSW) solution of the solar neutrino problem is discussed. One verification experiment concerns the detection of sizeable oscillations of atmospheric neutrinos in the earth, which can be detected with the massive underground proton decay detectors. Diurnal and seasonal modulations of the solar neutrino flux can perhaps be detected by the radiochemical Cl and Ga detectors. Moreover, neutrino oscillations in the Earth may modify the values of the oscillation parameters which can solve the solar neutrino problem and help determine their values. (UK)

  3. Big Bang Nucleosynthesis and Cosmological Constraints on Neutrino Oscillation Parameters

    CERN Document Server

    Kirilova, Daniela P; Kirilova, Daniela; Chizhov, Mihail

    2001-01-01

    We present a review of cosmological nucleosynthesis (CN) with neutrino oscillations, discussing the different effects of oscillations on CN, namely: increase of the effective degrees of freedom during CN, spectrum distortion of the oscillating neutrinos, neutrino number density depletion, and growth of neutrino-antineutrino asymmetry due to active-sterile oscillations. We discuss the importance of these effects for the primordial yield of helium-4. Primordially produced He-4 value is obtained in a selfconsistent study of the nucleons and the oscillating neutrinos. The effects of spectrum distortion, depletion and neutrino-antineutrino asymmetry growth on helium-4 production are explicitly calculated. An update of the cosmological constraints on active-sterile neutrino oscillations parameters is presented, giving the values: delta m^2 sin^8 (2 theta) 0, and |delta m^2| < 8.2 x 10^{-10} eV^2 at large mixing angles for delta m^2 < 0. According to these constraints, besides the active-sterile LMA solution,...

  4. Limits on neutrino oscillations in the CNGS neutrino beam and event classification with the OPERA detector

    Energy Technology Data Exchange (ETDEWEB)

    Ferber, Torben

    2012-09-15

    OPERA, the oscillation project with emulsion-tracking apparatus, is a long-baseline neutrino oscillation experiment. It combines an almost pure, high-energy {nu}{sub {mu}} beam produced at the SPS accelerator at CERN, Switzerland, with the OPERA neutrino detector located at a distance of about 730 km in the LNGS underground laboratory in Italy. By using a lead/photo emulsion target, {nu}{sub {tau}} charged current (CC) interactions of {nu}{sub {tau}} from {nu}{sub {mu}} {yields} {nu}{sub {tau}} oscillations can be observed on an event-by-event basis with very low background rates. Within this thesis, a {nu}{sub {mu}}{yields}{nu}{sub {mu}} disappearance search is described that uses a flux normalization. independent measurement of the CC event fraction as a function of the hadronic energy as measured by the electronic detectors of OPERA. This allows to derive limits on {nu}{sub {mu}}{yields}{nu}{sub {mu}} oscillations, complementary to the main {nu}{sub {tau}} appearance analysis. For maximal mixing, vertical stroke {Delta}m{sup 2}{sub 23} vertical stroke >4.4 x 10{sup -3} eV{sup 2} is excluded at 90% C.L. by the disappearance analysis. This thesis represents the first application of this method, including systematic uncertainties, in a long-baseline neutrino oscillation experiment.

  5. Magnus approximation in neutrino oscillations

    International Nuclear Information System (INIS)

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

    2011-01-01

    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.

  6. Effects of neutrino oscillation on supernova neutrino: inverted mass hierarchy

    International Nuclear Information System (INIS)

    Takahashi, Keitaro; Sato, Katsuhiko

    2003-01-01

    We study the effects of neutrino oscillation on supernova neutrino in the case of the inverted mass hierarchy (m 3 1 2 ). This is an extended study of our previous study where all analyses are performed with normal mass hierarchy (m 1 2 3 ). Numerical analysis using a realistic supernova and presupernova model allow us to discuss quantitatively a possibility to probe neutrino oscillation parameters. We show that we can break partly the degeneracy of the solar neutrino problem (LMA or SMA) and probe the magnitude of θ 13 to some extent by the ratios of high-energy events and low-energy events at SuperKamiokande and SNO and the presence of the Earth effects. Further, if the magnitude of θ 13 is known roughly, we can identify the mass hierarchy

  7. Neutrino Oscillations within the Induced Gravitational Collapse Paradigm of Long Gamma-Ray Bursts

    Science.gov (United States)

    Becerra, L.; Guzzo, M. M.; Rossi-Torres, F.; Rueda, J. A.; Ruffini, R.; Uribe, J. D.

    2018-01-01

    The induced gravitational collapse paradigm of long gamma-ray bursts associated with supernovae (SNe) predicts a copious neutrino–antineutrino (ν \\bar{ν }) emission owing to the hypercritical accretion process of SN ejecta onto a neutron star (NS) binary companion. The neutrino emission can reach luminosities of up to 1057 MeV s‑1, mean neutrino energies of 20 MeV, and neutrino densities of 1031 cm‑3. Along their path from the vicinity of the NS surface outward, such neutrinos experience flavor transformations dictated by the neutrino-to-electron-density ratio. We determine the neutrino and electron on the accretion zone and use them to compute the neutrino flavor evolution. For normal and inverted neutrino mass hierarchies and within the two-flavor formalism ({ν }e{ν }x), we estimate the final electronic and nonelectronic neutrino content after two oscillation processes: (1) neutrino collective effects due to neutrino self-interactions where the neutrino density dominates, and (2) the Mikheyev–Smirnov–Wolfenstein effect, where the electron density dominates. We find that the final neutrino content is composed by ∼55% (∼62%) of electronic neutrinos, i.e., {ν }e+{\\bar{ν }}e, for the normal (inverted) neutrino mass hierarchy. The results of this work are the first step toward the characterization of a novel source of astrophysical MeV neutrinos in addition to core-collapse SNe and, as such, deserve further attention.

  8. Observation of oscillations of atmospheric neutrinos with the IceCube Neutrino Observatory

    International Nuclear Information System (INIS)

    Euler, Sebastian

    2014-01-01

    Neutrino oscillations have become one of the most important research topics in particle physics since their discovery 15 years ago. In the past, the study of neutrino oscillations has been largely the domain of dedicated experiments, but in the last year also the large-volume neutrino telescopes ANTARES and IceCube reported their results on the oscillations of atmospheric muon neutrinos and thus joined the community of experiments studying neutrino oscillations. The precision of their results is not yet competitive, but their sheer size and the consequently enormous statistics give rise to the expectation of a competitive measurement in the future. This thesis describes an analysis that was done on IceCube data taken with the nearly complete detector in the years 2010/2011. IceCube is the world's largest neutrino detector, located at the geographic South Pole, where it uses the Antarctic ice sheet as its detection medium. It detects neutrinos interacting within or close to the instrumented volume by observing the Cherenkov light which is emitted by secondary particles produced in these interactions. An array of optical sensors deployed within a cubic kilometer of ice detects the Cherenkov light and makes it possible to reconstruct the energy and direction of the initial neutrino. Unfortunately, IceCube detects not only neutrinos: the desired neutrino signal is buried in a huge background of atmospheric muons, produced in air showers induced by cosmic rays. This background has to be rejected first. The analysis presented here employs an event selection that is based on the idea of using the outer layers of IceCube as an active veto against the background of atmospheric muons and achieves the necessary background rejection of more than 6 orders of magnitude while keeping a high-statistics sample of several thousands of muon neutrinos. In contrast to the earlier IceCube analysis, which used only the zenith angle, it then performs a 2-dimensional likelihood fit on

  9. Measuring neutrino oscillation parameters using $\

    Energy Technology Data Exchange (ETDEWEB)

    Backhouse, Christopher James [Oriel College, Oxford (United Kingdom)

    2011-01-01

    MINOS is a long-baseline neutrino oscillation experiment. It consists of two large steel-scintillator tracking calorimeters. The near detector is situated at Fermilab, close to the production point of the NuMI muon-neutrino beam. The far detector is 735 km away, 716m underground in the Soudan mine, Northern Minnesota. The primary purpose of the MINOS experiment is to make precise measurements of the 'atmospheric' neutrino oscillation parameters (Δmatm2 and sin2atm). The oscillation signal consists of an energy-dependent deficit of vμ interactions in the far detector. The near detector is used to characterize the properties of the beam before oscillations develop. The two-detector design allows many potential sources of systematic error in the far detector to be mitigated by the near detector observations. This thesis describes the details of the vμ-disappearance analysis, and presents a new technique to estimate the hadronic energy of neutrino interactions. This estimator achieves a significant improvement in the energy resolution of the neutrino spectrum, and in the sensitivity of the neutrino oscillation fit. The systematic uncertainty on the hadronic energy scale was re-evaluated and found to be comparable to that of the energy estimator previously in use. The best-fit oscillation parameters of the vμ-disappearance analysis, incorporating this new estimator were: Δm2 = 2.32-0.08+0.12 x 10-3 eV2, sin 2 2θ > 0.90 (90% C.L.). A similar analysis, using data from a period of running where the NuMI beam was operated in a configuration producing a predominantly $\\bar{v}$μ beam, yielded somewhat different best-fit parameters Δ$\\bar{m}${sup 2} = (3.36-0.40+0.46(stat.) ± 0.06(syst.)) x 10-3eV2, sin2 2$\\bar{θ}$ = 0.86-0.12_0

  10. Neutrino oscillation experiments

    International Nuclear Information System (INIS)

    Camilleri, L.

    1996-01-01

    Neutrino oscillation experiments (ν μ →ν e and ν μ →ν τ ) currently being performed at accelerators are reviewed. Future plans for short and long base-line experiments are summarized. (author) 10 figs., 2 tabs., 29 refs

  11. Exploration of CPT violation via time-dependent geometric quantities embedded in neutrino oscillation through fluctuating matter

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zisheng, E-mail: zishengwang@yahoo.com [College of Physics and Communication Electronics, Jiangxi Normal University, Nanchang 330022 (China); Institute of Applied Physics and Materials Engineering, University of Macau, Macao SAR (China); Pan, Hui, E-mail: huipan@umac.mo [Institute of Applied Physics and Materials Engineering, University of Macau, Macao SAR (China)

    2017-02-15

    We propose a new approach to explore CPT violation of neutrino oscillations through a fluctuating matter based on time-dependent geometric quantities. By mapping the neutrino oscillations onto a Poincaré sphere structure, we obtain an analytic solution of master equation and further define the geometric quantities, i.e., radius of Poincaré sphere and geometric phase. We find that the mixing process between electron and muon neutrinos can be described by the radius of Poincaré sphere that depends on the intrinsic CP-violating angle. Such a radius reveals a dynamic mechanism of CPT-violation, i.e., both spontaneous symmetry breaking and Majorana–Dirac neutrino confusion. We show that the time-dependent geometric phase can be used to find the neutrino nature and observe the CPT-violation because it is strongly enhanced under the neutrino propagation. We further show that the time-dependent geometric phase can be easily detected by simulating the neutrino oscillation based on fluctuating magnetic fields in nuclear magnetic resonance, which makes the experimental observation of CPT-violation possible in the neutrino mixing and oscillations.

  12. Spectrometry of the Earth using Neutrino Oscillations

    Science.gov (United States)

    Rott, C.; Taketa, A.; Bose, D.

    2015-01-01

    The unknown constituents of the interior of our home planet have provoked the human imagination and driven scientific exploration. We herein demonstrate that large neutrino detectors could be used in the near future to significantly improve our understanding of the Earth’s inner chemical composition. Neutrinos, which are naturally produced in the atmosphere, traverse the Earth and undergo oscillations that depend on the Earth’s electron density. The Earth’s chemical composition can be determined by combining observations from large neutrino detectors with seismic measurements of the Earth’s matter density. We present a method that will allow us to perform a measurement that can distinguish between composition models of the outer core. We show that the next-generation large-volume neutrino detectors can provide sufficient sensitivity to reject extreme cases of outer core composition. In the future, dedicated instruments could be capable of distinguishing between specific Earth composition models and thereby reshape our understanding of the inner Earth in previously unimagined ways. PMID:26489447

  13. Chaotic amplification of neutrino chemical potentials by neutrino oscillations in big bang nucleosynthesis

    International Nuclear Information System (INIS)

    Shi, X.

    1996-01-01

    We investigate in detail the parameter space of active-sterile neutrino oscillations that amplifies neutrino chemical potentials at the epoch of big bang nucleosynthesis. We calculate the magnitude of the amplification and show evidence of chaos in the amplification process. We also discuss the implications of the neutrino chemical potential amplification in big bang nucleosynthesis. It is shown that with a ∼1 eV ν e , the amplification of its chemical potential by active-sterile neutrino oscillations can lower the effective number of neutrino species at big bang nucleosynthesis to significantly below three. copyright 1996 The American Physical Society

  14. Chaotic amplification of neutrino chemical potentials by neutrino oscillations in big bang nucleosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Shi, X. [Department of Physics, Queen`s University, Kingston, Ontario, K7L 3N6 (CANADA)

    1996-08-01

    We investigate in detail the parameter space of active-sterile neutrino oscillations that amplifies neutrino chemical potentials at the epoch of big bang nucleosynthesis. We calculate the magnitude of the amplification and show evidence of chaos in the amplification process. We also discuss the implications of the neutrino chemical potential amplification in big bang nucleosynthesis. It is shown that with a {approximately}1 eV {nu}{sub {ital e}}, the amplification of its chemical potential by active-sterile neutrino oscillations can lower the effective number of neutrino species at big bang nucleosynthesis to significantly below three. {copyright} {ital 1996 The American Physical Society.}

  15. Neutrino mass spectrum with υμ → υs oscillations of atmospheric neutrinos

    International Nuclear Information System (INIS)

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

    1998-02-01

    We consider the ''standard'' spectrum of the active neutrinos (characterized by strong mass hierarchy and small mixing) with additional sterile, υ s . The sterile neutrino mixes strongly with the muon neutrino, so that υ μ ↔ υ s oscillations solve the atmospheric neutrino problem. We show that the parametric enhancement of the υ μ ↔ υ 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 υ μ and υ s . The heaviest neutrino (approx. υ τ ) may compose the hot dark matter of the Universe. Phenomenology of this scenario is elaborated and crucial experimental signatures are identified. We also discuss properties of the underlying neutrino mass matrix. (author)

  16. A measurement of hadron production cross sections for the simulation of accelerator neutrino beams and a search for muon-neutrino to electron-neutrino oscillations in the Δm2 about equals 1-eV2 region

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, David W. [Columbia Univ., New York, NY (United States)

    2008-01-01

    A measurement of hadron production cross-sections for the simulation of accelerator neutrino beams and a search for muon neutrino to electron neutrino oscillations in the Δm2 ~ 1 eV2} region. This dissertation presents measurements from two different high energy physics experiments with a very strong connection: the Hadron Production (HARP) experiment located at CERN in Geneva, Switzerland, and the Mini Booster Neutrino Experiment (Mini-BooNE) located at Fermilab in Batavia, Illinois.

  17. Observation of Electron Neutrino Appearance in the NuMI Beam with the NOvA Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Niner, Evan David [Indiana Univ., Bloomington, IN (United States)

    2015-01-01

    NOvA is a long-baseline neutrino oscillation experiment that uses two functionally identical detectors separated by 810 kilometers at locations 14 milliradians off-axis from the NuMI muon neutrino beam at Fermilab. At these locations the beam energy peaks at 2 GeV. This baseline is the longest in the world for an accelerator-based neutrino oscillation experiment, which enhances the sensitivity to the neutrino mass ordering. The experiment studies oscillations of the muon neutrino and anti-neutrino beam that is produced. Both detectors completed commissioning in the summer of 2014 and continue to collect data. One of the primary physics goals of the experiment is the measurement of electron neutrino appearance in the muon neutrino beam which yields measurements of the oscillation parameters sin213, δ , and the neutrino mass ordering within the standard model of neutrino oscillations. This thesis presents the analysis of data collected between February 2014 and May 2015, corresponding to 3.52 X 1020 protons-on-target. In this first analysis NOvA recorded 6 electron neutrino candidates, which is a 3.3σ observation of electron neutrino appearance. The T2K experiment performs the same measurement on a baseline of 295 kilometers and has a 1 σ preference for the normal mass ordering over the inverted ordering over the phase space of the CP violating parameter δ, which is also weakly seen in the NOvA result. By the summer of 2016 NOvA will triple its statistics due to increased beam power and a completed detector. If electron neutrinos continue to be observed at the current rate NOvA will be able to establish a mass ordering preference at a similar confidence level to T2K.

  18. Neutrino oscillations in curved spacetime: A heuristic treatment

    International Nuclear Information System (INIS)

    Cardall, C.Y.; Fuller, G.M.

    1997-01-01

    We discuss neutrino oscillations in curved spacetime. Our heuristic approach can accommodate matter effects and gravitational contributions to neutrino spin precession in the presence of a magnetic field. By way of illustration, we perform explicit calculations in the Schwarzschild geometry. In this case, gravitational effects on neutrino oscillations are intimately related to the redshift. We discuss how spacetime curvature could affect the resonance position and adiabaticity of matter-enhanced neutrino flavor conversion. copyright 1997 The American Physical Society

  19. Matter oscillations and solar neutrinos: A review of the MSW (Mikheyev-Smirnov-Wolfenstein) effect

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, S.P.; Gelb, J.M.

    1986-07-16

    We review the theory of the Mikheyev-Smirnov-Wolfenstein effect, in which matter oscillations can greatly enhance ''in vacuo'' neutrino oscillations, and we examine its consequences for the solar neutrino problem. Using a two-flavor model, we discuss the solutions in the ..delta..m/sup 2/-sin/sup 2/2THETA parameter space for the /sup 37/Cl experiment, and describe their predictions for the /sup 71/Ga experiment and for the spectrum of electron-neutrinos arriving at earth. We also comment on the three-flavor case.

  20. GENIUS Project, Neutrino Oscillations and Cosmology: Neutrinos Reveal Their Nature ?

    International Nuclear Information System (INIS)

    Czakon, M.; Studnik, J.; Zralek, M.; Gluza, J.

    2000-01-01

    The neutrinoless double beta decay as well as any other laboratory experiment has not been able to answer the question of the neutrino's nature. Hints on the answer are available when neutrino oscillations and (ββ) 0ν are considered simultaneously. In this case phenomenologically interesting neutrino mass schemes can lead to non-vanishing and large values of (m ν ). As a consequence, some schemes with Majorana neutrinos can be ruled out even now. If we assume that in addition neutrinos contribute to Hot Dark Matter then the window for Majorana neutrinos is even more restricted, e.g. GENIUS experiment will be sensitive to scenarios with three Majorana neutrinos. (author)

  1. Neutrino oscillation experiments

    Energy Technology Data Exchange (ETDEWEB)

    Camilleri, L [European Organization for Nuclear Research, Geneva (Switzerland)

    1996-11-01

    Neutrino oscillation experiments ({nu}{sub {mu}}{yields}{nu}{sub e} and {nu}{sub {mu}}{yields}{nu}{sub {tau}}) currently being performed at accelerators are reviewed. Future plans for short and long base-line experiments are summarized. (author) 10 figs., 2 tabs., 29 refs.

  2. Neutrino-electron scattering and the choice between different MSW solutions of the solar neutrino problem

    International Nuclear Information System (INIS)

    Rosen, S.P.; Gelb, J.M.

    1989-01-01

    This paper considers the scattering of solar neutrinos by electrons as a means for distinguishing between different MSW solutions of the solar neutrino problem. In terms of the ratio R between the observed cross-section and that for pure electron-type neutrinos, some correlation between the value of R and each solution is found. A value of R ≤ 1/3 implies that the adiabatic solution is correct, while values between 1/3 and 3/5 are consistent with the large angle solution. A value close to 1/2 is also consistent with the non-adiabatic solution, and a value less than (1/6 - 1/7) implies oscillations into sterile neutrinos

  3. Neutrino oscillations on the way to long-baseline experiments

    CERN Document Server

    Ryabov, V A

    2003-01-01

    The motivations and physical objectives of experiments in the search for nu /sub mu / to nu /sub e/, nu /sub tau / oscillations in long- baseline accelerator neutrino beams are reviewed. Neutrino beams, detectors, and methods for detecting oscillations (detection of the disappearance of nu /sub mu /, and the appearance of nu /sub e/ and nu /sub tau /) in the current K2K (KEK to Super Kamiokande) experiment and in the MINOS (FNAL to Soudan) and OPERA (CERN to Gran Sasso) near-future experiments are discussed. Possibilities of measuring the oscillation parameters in these experiments are considered in connection with new data obtained in CHOOZ and Palo Verde reactor experiments, the solar neutrino deficit and nu /sub mu // nu /sub e/ anomaly of atmospheric neutrinos, which are observed in large-scale underground detectors, and the excess of nu /sub e/ events in the LSND experiment. Neutrino-oscillation scenarios used in models with three and four (including sterile) types of neutrino, as well as the possibility...

  4. Implications of the Mikheyev-Smirnov-Wolfenstein (MSW) mechanism of amplification of neutrino oscillations in matter

    International Nuclear Information System (INIS)

    Langacker, P.; Petcov, S.T.; Steigman, G.; Toshev, S.

    1987-01-01

    Mikheyev and Smirnov have recently proposed a novel and plausible solution of the solar neutrino problem, based on the resonant amplification of the neutrino oscillations in matter. We comment on several aspects of this mechanism. (i) For the values of neutrino masses and mixing angles predicted by the seesaw model of grand unified theories, the MSW effect may take place naturally in the Sun, leading to a considerable reduction of the flux of solar electron neutrinos, with the dominant transition being ν e →ν τ (rather than ν e →ν μ ). (ii) Oscillations between the ordinary neutrinos (ν e ,ν μ ,ν τ ) can affect primordial nucleosynthesis, but the effect is small (i.e., the abundance of 4 He is predicted to change by less than 1.3x10 -3 ). (iii) A comparison of some of the general properties of neutrino oscillations in matter and in vacuum is given. (orig.)

  5. Movement of the pulsars and neutrino oscillations

    International Nuclear Information System (INIS)

    Barkovich, M.A.

    2005-01-01

    The astronomical observations show that the pulsars are not in the center of the remainder of the supernovae that gave its origin, but rather are displaced of the same one and moving to a speed of about 500 km/s, which is much bigger that of the progenitor star. This fact constitutes a strong evidence that the pulsars is accelerated in the moment of its birth and by this it is denominated to this phenomenon 'pulsars kick'. They exist numerous and varied mechanisms to explain this effect, but none makes it in way completely satisfactory. In this thesis we will study in detail a mechanism proposed originally by Kusenko and Segre and that is based on an asymmetric emission of the neutrinos flow induced by the oscillations of the same ones when its spread in a magnetized media. For this end we will develop, in first instance, the Eddington model. This is based on the transport of the neutrino flux and it describes in a reasonable way the atmosphere of a neutron protostar, place where take place the oscillations. Next we will study the problem of the emission of a neutrino gas from a resonance volume. These results will be applied to the study of the kick in the cases of oscillations among active neutrinos and actives with sterile to determine the magnetic field and the oscillation parameters (difference of the square of the masses of those neutrinos and mixture angle in vacuum) required. Finally we will analyze those neutrino oscillations induced by a possible violation of the Equivalence principle and it implication in the pulsars dynamics. (Author)

  6. A measurement of neutrino oscillations with muon neutrinos in the MINOS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, Stephen James [College of William and Mary, Williamsburg, VA (United States)

    2011-05-01

    Experimental evidence has established that neutrino flavor states evolve over time. A neutrino of a particular flavor that travels some distance can be detected in a different neutrino flavor state. The Main Injector Neutrino Oscillation Search (MINOS) is a long-baseline experiment that is designed to study this phenomenon, called neutrino oscillations. MINOS is based at Fermilab near Chicago, IL, and consists of two detectors: the Near Detector located at Fermilab, and the Far Detector, which is located in an old iron mine in Soudan, MN. Both detectors are exposed to a beam of muon neutrinos from the NuMI beamline, and MINOS measures the fraction of muon neutrinos that disappear after traveling the 734 km between the two detectors. One can measure the atmospheric neutrino mass splitting and mixing angle by observing the energy-dependence of this muon neutrino disappearance. MINOS has made several prior measurements of these parameters. Here I describe recently-developed techniques used to enhance our sensitivity to the oscillation parameters, and I present the results obtained when they are applied to a dataset that is twice as large as has been previously analyzed. We measure the mass splitting Δm232 = (2.32-0.08+0.12) x 10-3 eV2/c4 and the mixing angle sin2(2θ32) > 0.90 at 90% C.L. These results comprise the world's best measurement of the atmospheric neutrino mass splitting. Alternative disappearance models are also tested. The neutrino decay hypothesis is disfavored at 7.2σ and the neutrino quantum decoherence hypothesis is disfavored at 9.0σ.

  7. Neutrino Oscillations at Reactors: What Next?

    OpenAIRE

    Mikaelyan, L. A.; Sinev, V. V.

    1999-01-01

    We shortly review past and future experiments at reactors aimed at searches for neutrino masses and mixing. We also consider new idea to search at Krasnoyarsk for small mixing angle oscillations in the atmosheric neutrino mass parameter region.

  8. Neutrino oscillations in a predictive SUSY GUT

    International Nuclear Information System (INIS)

    Blazek, T.; Raby, S.; Tobe, K.

    1999-01-01

    In this paper we present a predictive SO(10) supersymmetric grand unified theory with the family symmetry U(2)xU(1) which has several nice features. We are able to fit fermion masses and mixing angles, including recent neutrino data, with nine parameters in the charged fermion sector and four in the neutrino sector. The family symmetry plays a preeminent role. (i) The model is ''natural''--we include all terms allowed by the symmetry. It restricts the number of arbitrary parameters and enforces many zeros in the effective mass matrices. (ii) Family symmetry breaking from U(2)xU(1)→U(1)→ nothing generates the family hierarchy. It also constrains squark and slepton mass matrices, thus ameliorating flavor violation resulting from squark and slepton loop contributions. (iii) It naturally gives large angle ν μ -ν τ mixing describing atmospheric neutrino oscillation data and small angle ν e -ν s mixing, consistent with the small mixing angle Mikheyev-Smirnov-Wolfenstein (MSW) solution to solar neutrino data. (iv) Finally, in this paper we assume minimal family symmetry-breaking vacuum expectation values (VEV's). As a result we cannot obtain a three neutrino solution to both atmospheric and solar neutrino oscillations. In addition, the solution discussed here cannot fit liquid scintillation neutrino detector (LSND) data even though this solution requires a sterile neutrino ν s . It is important to note, however, that with nonminimal family symmetry-breaking VEV's, a three neutrino solution is possible with the small mixing angle MSW solution to solar neutrino data and large angle ν μ -ν τ mixing describing atmospheric neutrino oscillation data. In the four neutrino case, nonminimal family VEV's may also permit a solution for LSND. The results with nonminimal family breaking are still under investigation and will be reported in a future paper. (c) 1999 The American Physical Society

  9. Long baseline neutrino oscillation experiment at the AGS. Physics design report

    Energy Technology Data Exchange (ETDEWEB)

    Beavis, D.; Carroll, A.; Chiang, I. [Brookhaven National Lab., Long Island, NY (United States); E889 Collaboration

    1995-04-01

    The authors present a design for a multi-detector long baseline neutrino oscillation experiment at the BNL AGS. It has been approved by the BNL-HENP-PAC as AGS Experiment 889. The experiment will search for oscillations in the {nu}{sub {mu}}, disappearance channel and the {nu}{sub {mu}} {leftrightarrow} {nu}{sub e} appearance channel by means of four identical neutrino detectors located 1, 3, 24, and 68km from the AGS neutrino source. Observed depletion of the {nu}{sub {mu}} flux (via quasi-elastic muon neutrino events, {nu}{sub {mu}}n {yields} {mu}{sup {minus}}p) in the far detectors not attended by an observed proportional increase of the {nu}{sub e} flux (via quasi-elastic electron neutrino events, {nu}{sub e}n {yields} e{sup {minus}}p) in those detectors will be prima facie evidence for the oscillation channel {nu}{sub {mu}} {leftrightarrow} {nu}{sub {tau}}. The experiment is directed toward exploration of the region of the neutrino oscillation parameters {Delta}m{sup 2} and sin{sup 2}2{theta}, suggested by the Kamiokande and IMB deep underground detectors but it will also explore a region more than two orders of magnitude larger than that of previous accelerator experiments. The experiment will run in a mode new to BNL. It will receive the fast extracted proton beam on the neutrino target approximately 20 hours per day when the AGS is not filling RHIC. A key aspect of the experimental design involves placing the detectors 1.5 degrees off the center line of the neutrino beam, which has the important advantage that the central value of the neutrino energy ({approx} 1 GeV) and the beam spectral shape are, to a good approximation, the same in all four detectors. The proposed detectors are massive, imaging, water Cherenkov detectors similar in large part to the Kamiokande and IMB detectors. The design has profited from their decade-long experience, and from the detector designs of the forthcoming SNO and SuperKamiokande detectors.

  10. Long baseline neutrino oscillation experiment at the AGS. Physics design report

    International Nuclear Information System (INIS)

    Beavis, D.; Carroll, A.; Chiang, I.

    1995-04-01

    The authors present a design for a multi-detector long baseline neutrino oscillation experiment at the BNL AGS. It has been approved by the BNL-HENP-PAC as AGS Experiment 889. The experiment will search for oscillations in the ν μ , disappearance channel and the ν μ ↔ ν e appearance channel by means of four identical neutrino detectors located 1, 3, 24, and 68km from the AGS neutrino source. Observed depletion of the ν μ flux (via quasi-elastic muon neutrino events, ν μ n → μ - p) in the far detectors not attended by an observed proportional increase of the ν e flux (via quasi-elastic electron neutrino events, ν e n → e - p) in those detectors will be prima facie evidence for the oscillation channel ν μ ↔ ν τ . The experiment is directed toward exploration of the region of the neutrino oscillation parameters Δm 2 and sin 2 2θ, suggested by the Kamiokande and IMB deep underground detectors but it will also explore a region more than two orders of magnitude larger than that of previous accelerator experiments. The experiment will run in a mode new to BNL. It will receive the fast extracted proton beam on the neutrino target approximately 20 hours per day when the AGS is not filling RHIC. A key aspect of the experimental design involves placing the detectors 1.5 degrees off the center line of the neutrino beam, which has the important advantage that the central value of the neutrino energy (∼ 1 GeV) and the beam spectral shape are, to a good approximation, the same in all four detectors. The proposed detectors are massive, imaging, water Cherenkov detectors similar in large part to the Kamiokande and IMB detectors. The design has profited from their decade-long experience, and from the detector designs of the forthcoming SNO and SuperKamiokande detectors

  11. Compact perturbative expressions for neutrino oscillations in matter

    Energy Technology Data Exchange (ETDEWEB)

    Denton, Peter B. [Theoretical Physics Department, Fermi National Accelerator Laboratory,P.O. Box 500, Batavia, IL 60510 (United States); Physics & Astronomy Department, Vanderbilt University,PMB 401807, 2301 Vanderbilt Place, Nashville, TN 37235 (United States); Minakata, Hisakazu [Instituto de Física, Universidade de São Paulo,C.P. 66.318, 05315-970 São Paulo (Brazil); Department of Physics, Yachay Tech University,San Miguel de Urcuquí 100119 (Ecuador); Parke, Stephen J. [Theoretical Physics Department, Fermi National Accelerator Laboratory,P.O. Box 500, Batavia, IL 60510 (United States)

    2016-06-08

    We further develop and extend a recent perturbative framework for neutrino oscillations in uniform matter density so that the resulting oscillation probabilities are accurate for the complete matter potential versus baseline divided by neutrino energy plane. This extension also gives the exact oscillation probabilities in vacuum for all values of baseline divided by neutrino energy. The expansion parameter used is related to the ratio of the solar to the atmospheric Δm{sup 2} scales but with a unique choice of the atmospheric Δm{sup 2} such that certain first-order effects are taken into account in the zeroth-order Hamiltonian. Using a mixing matrix formulation, this framework has the exceptional feature that the neutrino oscillation probability in matter has the same structure as in vacuum, to all orders in the expansion parameter. It also contains all orders in the matter potential and sin θ{sub 13}. It facilitates immediate physical interpretation of the analytic results, and makes the expressions for the neutrino oscillation probabilities extremely compact and very accurate even at zeroth order in our perturbative expansion. The first and second order results are also given which improve the precision by approximately two or more orders of magnitude per perturbative order.

  12. Results of a neutrino oscillation experiment performed at a meson factory beam-stop

    International Nuclear Information System (INIS)

    Mitchell, J.W.

    1989-04-01

    This document describes a neutrino oscillation experiment performed at the Los Alamos Meson Physics Facility. The oscillation mode searched for is /bar /nu///sub μ/ → /bar /nu///sub e/. The first chapter is a review of the known properties of the neutrino and a description of the phenomenon of neutrino oscillation. Previous experimental limits on this unobserved phenomenon are also given. The second chapter describes the experimental apparatus used by the E645 experiment to detect neutrinos produced in the LAMPF beam stop. The salient features of the detector are its large mass (20 tons of CH 2 ), its fine segmentation (to allow good particle tracking), good energy resolution, its recording of the history both before and after tracks appear in the detector, an active cosmic-ray anticoincidence shield, and 2000 gm/cm 2 of passive cosmic-ray shielding. It is located 26.8 m from the neutrino source, which has a mean neutrino energy of 40 MeV. The third chapter details the reduction of the 1.3 million event data sample to a 49 event sample of neutrino candidates. Principle backgrounds are Michel electrons from stopping cosmic-ray muons and protons from np elastic scattering by cosmic-ray neutrons. The fourth chapter explains how background levels from neutrino-nuclear scattering are predicted. The result of a maximum-likelihood analysis reveals no evidence for oscillation. 90% confidence levels are set at δm 2 = .10 eV 2 for large mixing and sin 2 (2θ) = .014 for large δm 2 . 82 refs., 18 figs., 55 tabs

  13. Supernova nucleosynthesis and the physics of neutrino oscillation

    Energy Technology Data Exchange (ETDEWEB)

    Kajino, Toshitaka [National Astronomical Observatory, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan) and Department of Astronomy, Graduate School of Science, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2012-11-20

    We studied the explosive nucleosynthesis in core-collapse supernovae and found that several isotopes of rare elements like {sup 7}Li, {sup 11}B, {sup 138}La, {sup 180}Ta and others are predominantly produced by the neutrino interactions with several abundant nuclei. These isotopes are strongly affected by the neutrino flavor oscillation due to the MSW (Mikheyev-Smirnov-Wolfenstein) effect. We here first study how to know the suitable average 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 neutrino oscillation effects on their abundances, and propose a new novel method to determine the neutrino oscillation parameters, {theta}{sub 13} and mass hierarchy, simultaneously. There is recent evidence that some SiC X grains from the Murchison meteorite may contain supernova-produced neutrino-process {sup 11}B and {sup 7}Li encapsulated in the grains. Combining the recent experimental constraints on {theta}{sub 13}, we show that although the uncertainties are still large, our method hints at a marginal preference for an inverted neutrino mass hierarchy for the first time.

  14. Supernova nucleosynthesis and the physics of neutrino oscillation

    Science.gov (United States)

    Kajino, Toshitaka

    2012-11-01

    We studied the explosive nucleosynthesis in core-collapse supernovae and found that several isotopes of rare elements like 7Li, 11B, 138La, 180Ta and others are predominantly produced by the neutrino interactions with several abundant nuclei. These isotopes are strongly affected by the neutrino flavor oscillation due to the MSW (Mikheyev-Smirnov-Wolfenstein) effect. We here first study how to know the suitable average 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 neutrino oscillation effects on their abundances, and propose a new novel method to determine the neutrino oscillation parameters, θ13 and mass hierarchy, simultaneously. There is recent evidence that some SiC X grains from the Murchison meteorite may contain supernova-produced neutrino-process 11B and 7Li encapsulated in the grains. Combining the recent experimental constraints on θ13, we show that although the uncertainties are still large, our method hints at a marginal preference for an inverted neutrino mass hierarchy for the first time.

  15. The MSW Effect and Matter Effects in Neutrino Oscillations

    Science.gov (United States)

    Smirnov, A. Yu.

    2006-03-01

    The MSW (Mikheyev-Smirnov-Wolfenstein) effect is the adiabatic or partially adiabatic neutrino flavor conversion in media with varying density. The main notions related to the effect, its dynamics and physical picture are reviewed. The large mixing MSW effect is realized inside the Sun providing a solution of the solar neutrino problem. The small mixing MSW effect driven by the 1-3 mixing can be realized for the supernova (SN) neutrinos. Inside collapsing stars new elements of the MSW dynamics may show up: non-oscillatory transition, non-adiabatic conversion, time dependent adiabaticity violation induced by shock waves. Effects of the resonance enhancement and the parametric enhancement of oscillations can be realized for atmospheric and accelerator neutrinos in the Earth. Precise results for neutrino oscillations in low density media with arbitrary density profile are presented and the attenuation effect is described. The area of applications is the solar and SN neutrinos inside the Earth, and the results are crucial for the neutrino oscillation tomography.

  16. Measurement of neutrino oscillations in atmospheric neutrinos with the IceCube DeepCore detector

    Energy Technology Data Exchange (ETDEWEB)

    Yanez Garza, Juan Pablo

    2014-06-02

    The study of neutrino oscillations is an active field of research. During the last couple of decades many experiments have measured the effects of oscillations, pushing the field from the discovery stage towards an era of precision and deeper understanding of the phenomenon. The IceCube Neutrino Observatory, with its low energy subarray, DeepCore, has the possibility of contributing to this field. IceCube is a 1 km{sup 3} ice Cherenkov neutrino telescope buried deep in the Antarctic glacier. DeepCore, a region of denser instrumentation in the lower center of IceCube, permits the detection of neutrinos with energies as low as 10 GeV. Every year, thousands of atmospheric neutrinos around these energies leave a strong signature in DeepCore. Due to their energy and the distance they travel before being detected, these neutrinos can be used to measure the phenomenon of oscillations. This work starts with a study of the potential of IceCube DeepCore to measure neutrino oscillations in different channels, from which the disappearance of ν{sub μ} is chosen to move forward. It continues by describing a novel method for identifying Cherenkov photons that traveled without being scattered until detected direct photons. These photons are used to reconstruct the incoming zenith angle of muon neutrinos. The total energy of the interacting neutrino is also estimated. In data taken in 343 days during 2011-2012, 1487 neutrino candidates with an energy between 7 GeV and 100 GeV are found inside the DeepCore volume. Compared to the expectation from the atmospheric neutrino flux without oscillations, this corresponds to a deficit of about 500 muon neutrino events. The oscillation parameters that describe the data best are sin{sup 2}(2θ{sub 23})=1(>0.94 at 68 % C.L.) and vertical stroke Δm{sup 2}{sub 32} vertical stroke =2.4{sub -0.4}{sup +0.6}.10{sup -3} eV{sup 2}, which are in agreement with the results reported by other experiments. The simulation follows the data closely

  17. Study of the atmospheric neutrino oscillations in the Frejus experiment

    International Nuclear Information System (INIS)

    Perdereau, O.

    1989-05-01

    The behavior of atmospheric neutrinos is investigated. It is a zero mass, zero charge and weak interacting particle. The aim of the investigation is to search for non standard phenomena, such as neutrino oscillations. The neutrino theoretical properties are discussed and the physical parameters experimental limits are recalled. The analysis of the approximately 200 events from atmospheric neutrinos observed in Frejus detector is carried out. The results and simulation of neutrino interactions are presented. The data analysis induces to the exclusion of neutrino oscillation hypothesis from some models. Three cases of oscillations involving two neutrino flavors are analyzed. The effect of a third flavor is also taken into account. The present data and those from IMB and Kamiokande experiments are compared. Topics involving investigations on the superposition of a signal and the atmospheric neutrinos are included [fr

  18. Future short baseline neutrino oscillation experiments

    CERN Document Server

    Camilleri, L L

    1999-01-01

    A neutrino mass that would make a significant contribution to the hidden mass of the universe and thus contribute to the solving of the dark matter puzzle is still the most valuable prize in neutrino physics. This would presumably be through a mixed dark matter scenario and would involve a neutrino mass of 1-2 eV. Assuming the Delta m/sup 2/ observed in neutrino oscillations is the difference between this mass and a negligible mass of a second neutrino, CHORUS and NOMAD would only have a sensitivity of sin/sup 2/ 2 theta ~10/sup -3/ in this domain. The aim of future nu /sub mu /- nu /sub tau / oscillation searches is therefore to improve the sensitivity of the search by about an order of magnitude. NOMAD has a number of events looking exactly like a nu /sub tau / interaction should but, in spite of the good kinematical capabilities of the experiment, the number of such events is consistent with the number of expected background events. Therefore to improve on this situation it is imperative to be able to dete...

  19. A road map to solar neutrino fluxe, neutrino oscillation parameters, and tests for new physics

    CERN Document Server

    Bahcall, J N; Bahcall, John N.; Peña-Garay, Carlos

    2003-01-01

    We analyze all available solar and related reactor neutrino experiments, as well as simulated future ^7Be, p-p, pep, and ^8B solar neutrino experiments. We treat all solar neutrino fluxes as free parameters subject to the condition that the total luminosity represented by the neutrinos equals the observed solar luminosity (the `luminosity constraint'). Existing experiments show that the p-p solar neutrino flux is 1.01 + - 0.02 (1 sigma) times the flux predicted by the BP00 standard solar model; the ^7Be neutrino flux is 0.97^{+0.28}_{-0.54} the predicted flux; and the ^8B flux is 1.01 + - 0.06 the predicted flux. The oscillation parameters are: Delta m^2 = 7.3^{+0.4}_{-0.6} 10^{-5} eV^2 and tan^2 theta_{12} = 0.42^{+0.08}_{-0.06}. We evaluate how accurate future experiments must be to determine more precisely neutrino oscillation parameters and solar neutrino fluxes, and to elucidate the transition from vacuum-dominated to matter-dominated oscillations. A future ^7Be nu-e scattering experiment accurate to + -...

  20. Neutrino oscillations - the Double Chooz experiment

    Energy Technology Data Exchange (ETDEWEB)

    Lasserre, Th. [CEA Saclay, Dept. d' Astrophysique, de Physique des Particules de Physique Nucleaire et de l' Instrumentation Associee (DSM/DAPNIA/SPP/APC), 91- Gif sur Yvette (France)

    2007-07-01

    {theta}{sub 13} is the mixing angle that couples the field of the neutrino number 3 (the heaviest) to the electron field. The Double Chooz experiment will use 2 identical detectors, near the Chooz nuclear reactor cores to measure the last undetermined mixing angle {theta}{sub 13}. The basic principle of the multi-detector concept is the cancellation of the reactor-induced systematic errors. The first detector will be installed in the existing underground laboratory (1050 meters away from the plant station) that was used in the first Chooz experiment in the nineties. The second detector will be constructed from 2009 in a new neutrino laboratory, located down a 45 m well that will be excavated 300 m away from the reactors. An average visible neutrino rate of 55 (550) events per day is expected to be detected inside the far (near) detector, taking into account the various inefficiencies, if no oscillations. The near detector will perform a measurement of the anti-neutrino flux and its energy spectrum with an unprecedented accuracy and for a long period (3 years). These huge statistics will also be exploited to monitor changes in the relative amounts of U{sup 235} and Pu{sup 239} in the core, paving the way to use neutrino detection for safeguards applications. (A.C.)

  1. Neutrino Oscillations Present Status and Future Plans

    CERN Document Server

    Thomas, Jennifer

    2008-01-01

    This book reviews the status of a very exciting field - neutrino oscillations - at a very important time. The fact that neutrinos have mass has only been proved in the last few years and the acceptance of that fact has opened up a whole new area of study to understand the fundamental parameters of the mixing matrix. The book summarizes the results from all the experiments which have played a role in the measurement of neutrino oscillations and briefly describes the scope of some new planned experiments. Contributions include a theoretical introduction by Stephen Parke from FNAL, as well as art

  2. Accelerator-based neutrino oscillation searches

    International Nuclear Information System (INIS)

    Whitehouse, D.; Rameika, G.

    1993-01-01

    This paper attempts to summarize the neutrino oscillation section of the Workshop on Future Directions in Particle and Nuclear Physics at Multi-GeV Hadron Beam Facilities. There were very lively discussions about the merits of the different oscillation channels, experiments, and facilities, but the authors believe a substantial consensus emerged

  3. Neutrino Oscillation Parameter Sensitivity in Future Long-Baseline Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Bass, Matthew [Colorado State Univ., Fort Collins, CO (United States)

    2014-01-01

    The study of neutrino interactions and propagation has produced evidence for physics beyond the standard model and promises to continue to shed light on rare phenomena. Since the discovery of neutrino oscillations in the late 1990s there have been rapid advances in establishing the three flavor paradigm of neutrino oscillations. The 2012 discovery of a large value for the last unmeasured missing angle has opened the way for future experiments to search for charge-parity symmetry violation in the lepton sector. This thesis presents an analysis of the future sensitivity to neutrino oscillations in the three flavor paradigm for the T2K, NO A, LBNE, and T2HK experiments. The theory of the three flavor paradigm is explained and the methods to use these theoretical predictions to design long baseline neutrino experiments are described. The sensitivity to the oscillation parameters for each experiment is presented with a particular focus on the search for CP violation and the measurement of the neutrino mass hierarchy. The variations of these sensitivities with statistical considerations and experimental design optimizations taken into account are explored. The effects of systematic uncertainties in the neutrino flux, interaction, and detection predictions are also considered by incorporating more advanced simulations inputs from the LBNE experiment.

  4. First Neutrino Oscillation Results from the NOvA experiment

    Energy Technology Data Exchange (ETDEWEB)

    Sachdev, Kanika [Fermilab

    2016-11-29

    NOvA is a long-baseline neutrino oscillation experiment on the NuMI muon neutrino beam at Fermilab. It consists of two functionally identical, nearly fully-active liquid-scintillator tracking calorimeters. The Near Detector (ND) at Fermilab is used to study the neutrino beam spectrum and composition before oscillations occur. The Far Detector in northern Minnesota, 810 km away, observes the oscillated beam and is used to extract the oscillation parameters. NOvA is designed to observe oscillations in two channels: disappearance channel ( ν μ → ν μ ) and ν e appearance channel ( ν μ → ν e ). This paper reports the measurements of both these channels based on the first NOvA data taken from February 16, 2014 till May 15, 2015

  5. From kaons to neutrinos: quantum mechanics of particle oscillations

    International Nuclear Information System (INIS)

    Zralek, M.

    1998-01-01

    The problem of particle oscillation is considered in a pedagogical and comprehensive way. Examples from K, B and neutrino physics are given. Conceptual difficulties of the traditional approach to particle oscillation are discussed. It is shown how the probability current density and the wave packet treatments of particle oscillations resolve some problems. It is also shown that only full field theoretical approach is free from conceptual difficulties. The possibility of oscillation of particles produced together with kaons or neutrinos is considered in full wave packet quantum mechanics language. Precise definition of the oscillation of particles which recoil against mixed states is given. The general amplitude which describes the oscillation of two particles in the final states is found. Using this EPR-type amplitude the problem of oscillation of particles recoiling against kaons or neutrinos is resolved. The relativistic EPR correlations on distances of the order of coherence lengths are considered. (author)

  6. Multipartite entanglement in neutrino oscillations

    International Nuclear Information System (INIS)

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

    2009-01-01

    Particle mixing is related to multi-mode entanglement of single-particle states The occupation number of both flavor eigenstates and mass eigenstates can be used to define a multiqubit space. In such a framework, flavor neutrino states can be interpreted as multipartite mode-entangled states. By using two different entanglement measures, we analyze the behavior of multipartite entanglement in the phenomenon of neutrino oscillations.

  7. Multipartite entanglement in neutrino oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Blasone, Massimo; Dell' Anno, Fabio; De Siena, Silvio; Illuminati, Fabrizio, E-mail: blasone@sa.infn.i [Dipartimento di Matematica e Informatica, Universita degli Studi di Salerno, Via Ponte don Melillo, I-84084 Fisciano (Italy)

    2009-06-01

    Particle mixing is related to multi-mode entanglement of single-particle states The occupation number of both flavor eigenstates and mass eigenstates can be used to define a multiqubit space. In such a framework, flavor neutrino states can be interpreted as multipartite mode-entangled states. By using two different entanglement measures, we analyze the behavior of multipartite entanglement in the phenomenon of neutrino oscillations.

  8. Nuclear effects in neutrino oscillation experiments

    International Nuclear Information System (INIS)

    Chauhan, S.; Athar, M. Sajjad; Singh, S. K.

    2011-01-01

    We have studied the nuclear medium effects in the neutrino(antineutrino) induced interactions in nuclei which are relevant for present neutrino oscillation experiments in the few GeV energy region. The study is specially focused on calculating the cross sections and the event rates for atmospheric and accelerator neutrino experiments. The nuclear effects are found to be important for the quasielastic lepton production and the charged current incoherent and coherent pion production processes.

  9. Physics Reach with a Monochromatic Neutrino Beam from Electron Capture

    CERN Document Server

    Bernabeu, J.; Espinoza, C.; Lindroos, M.

    2005-01-01

    Neutrino oscillation experiments from different sources have demonstrated non-vanishing neutrino masses and flavour mixings. The next experiments have to address the determination of the connecting mixing U(e3) and the existence of the CP violating phase. Whereas U(e3) measures the strength of the oscillation probability in appearance experiments, the CP phase acts as a phase-shift in the interference pattern. Here we propose to separate these two parameters by energy dependence, using the novel idea of a monochromatic neutrino beam facility based on the acceleration of ions that decay fast through electron capture. Fine tuning of the boosted neutrino energy allows precision measurements able to open a window for the discovery of CP violation, even for a mixing as small as 1 degree

  10. Analytic formulation of neutrino oscillation probability in constant matter

    International Nuclear Information System (INIS)

    Kimura, Keiichi; Takamura, Akira; Yokomakura, Hidekazu

    2003-01-01

    In this paper, based on the work (Kimura K et al 2002 Phys. Lett. B 537 86) we present the simple derivation of an exact and analytic formula for neutrino oscillation probability. We consider three flavour neutrino oscillations in matter with constant density

  11. Quasi-Dirac neutrino oscillations

    Science.gov (United States)

    Anamiati, Gaetana; Fonseca, Renato M.; Hirsch, Martin

    2018-05-01

    Dirac neutrino masses require two distinct neutral Weyl spinors per generation, with a special arrangement of masses and interactions with charged leptons. Once this arrangement is perturbed, lepton number is no longer conserved and neutrinos become Majorana particles. If these lepton number violating perturbations are small compared to the Dirac mass terms, neutrinos are quasi-Dirac particles. Alternatively, this scenario can be characterized by the existence of pairs of neutrinos with almost degenerate masses, and a lepton mixing matrix which has 12 angles and 12 phases. In this work we discuss the phenomenology of quasi-Dirac neutrino oscillations and derive limits on the relevant parameter space from various experiments. In one parameter perturbations of the Dirac limit, very stringent bounds can be derived on the mass splittings between the almost degenerate pairs of neutrinos. However, we also demonstrate that with suitable changes to the lepton mixing matrix, limits on such mass splittings are much weaker, or even completely absent. Finally, we consider the possibility that the mass splittings are too small to be measured and discuss bounds on the new, nonstandard lepton mixing angles from current experiments for this case.

  12. Derivation of the formalism for neutrino matter oscillations from the neutrino relativistic field equations

    International Nuclear Information System (INIS)

    Mannheim, P.D.

    1988-01-01

    We derive the standard formalism of Mikheyev, Smirnov, and Wolfenstein for the oscillation of neutrinos in matter taking into account the Lorentz and second-quantized structure of the neutrino fields. We consider neutrinos with Dirac or Majorana masses

  13. Supernova relic electron neutrinos and anti-neutrinos in future large-scale observatories

    International Nuclear Information System (INIS)

    Volpe, C.; Welzel, J.

    2007-01-01

    We investigate the signal from supernova relic neutrinos in future large scale observatories, such as MEMPHYS (UNO, Hyper-K), LENA and GLACIER, at present under study. We discuss that complementary information might be gained from the observation of supernova relic electron antineutrinos and neutrinos using the scattering on protons on one hand, and on nuclei such as oxygen, carbon or argon on the other hand. When determining the relic neutrino fluxes we also include, for the first time, the coupling of the neutrino magnetic moment to magnetic fields within the core collapse supernova. We present numerical results on both the relic ν e and ν-bar e fluxes and on the number of events for ν e + C 12 , ν e + O 16 , ν e + Ar 40 and ν-bar e + p for various oscillation scenarios. The observation of supernova relic neutrinos might provide us with unique information on core-collapse supernova explosions, on the star formation history and on neutrino properties, that still remain unknown. (authors)

  14. Electron Neutrino Charged-Current Quasielastic Scattering in the MINERvA Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Wolcott, Jeremy [Rochester U.

    2015-10-28

    The electron-neutrino charged-current quasielastic (CCQE) cross section on nuclei is an important input parameter to appearance-type neutrino oscillation experiments. Current experiments typically work from the muon neutrino cross section and apply corrections from theoretical arguments to obtain a prediction for the electron neutrino cross section, but to date there has been no experimental verification of the estimates for this channel at an energy scale appropriate to such experiments. We present the first measurement of an exclusive reaction in few-GeV electron neutrino interactions, namely, the cross section for a CCQE-like process, made using the MINERvA detector. The result is given as differential cross-sections vs. the electron energy, electron angle, and square of the four-momentum transferred to the nucleus, $Q^2$. We also compute the ratio to a muon neutrino cross-section in $Q^2$ from MINERvA. We find satisfactory agreement between this measurement and the predictions of the GENIE generator.

  15. Neutrino versus antineutrino oscillation parameters at DUNE and Hyper-Kamiokande experiments

    Science.gov (United States)

    de Gouvêa, André; Kelly, Kevin J.

    2017-11-01

    Testing, in a nontrivial, model-independent way, the hypothesis that the three-massive-neutrinos paradigm properly describes nature is among the main goals of the current and the next generation of neutrino oscillation experiments. In the coming decade, the DUNE and Hyper-Kamiokande experiments will be able to study the oscillation of both neutrinos and antineutrinos with unprecedented precision. We explore the ability of these experiments, and combinations of them, to determine whether the parameters that govern these oscillations are the same for neutrinos and antineutrinos, as prescribed by the C P T -theorem. We find that both DUNE and Hyper-Kamiokande will be sensitive to unexplored levels of leptonic C P T -violation. Assuming the parameters for neutrino and antineutrino oscillations are unrelated, we discuss the ability of these experiments to determine the neutrino and antineutrino mass-hierarchies, atmospheric-mixing octants, and C P -odd phases, three key milestones of the experimental neutrino physics program. Additionally, if the C P T -symmetry is violated in nature in a way that is consistent with all present neutrino and antineutrino oscillation data, we find that DUNE and Hyper-Kamiokande have the potential to ultimately establish leptonic C P T -invariance violation.

  16. Study of different type neutrino oscillations based on neutrino beams from 600 GeV

    International Nuclear Information System (INIS)

    Aref'ev, A.S.

    1994-01-01

    The problems of the different type neutrino oscillations based on a wide-band and narrow-band neutrino beam from the 600 GeV UNK-1 machine using the Baical Neutrino Telescope (4200 km from a accelerator) are discussed. The main parameters of the neutrino channel are presented. 17 refs.; 12 figs.; 1 tab

  17. Symmetry breaking, and the effect of matter density on neutrino oscillation

    Science.gov (United States)

    Mohseni Sadjadi, H.; Khosravi Karchi, A. P.

    2018-04-01

    A proposal for the neutrino mass, based on neutrino-scalar field interaction, is introduced. The scalar field is also non-minimally coupled to the Ricci scalar, and hence relates the neutrino mass to the matter density. In a dense region, the scalar field obeys the Z2 symmetry, and the neutrino is massless. In a dilute region, the Z2 symmetry breaks and neutrino acquires mass from the non-vanishing expectation value of the scalar field. We consider this scenario in the framework of a spherical dense object whose outside is a dilute region. In this background, we study the neutrino flavors oscillation, along with the consequences of the theory on oscillation length and MSW effect. This preliminary model may shed some lights on the existing anomalies within the neutrino data, concerning the different oscillating behavior of the neutrinos in regions with different densities.

  18. Nuclear weak interactions, supernova nucleosynthesis and neutrino oscillation

    Science.gov (United States)

    Kajino, Toshitaka

    2013-07-01

    We study the nuclear weak response in light-to-heavy mass nuclei and calculate neutrino-nucleus cross sections. We apply these cross sections to the explosive nucleosynthesis in core-collapse supernovae and find that several isotopes of rare elements 7Li, 11B, 138La, 180Ta and several others are predominantly produced by the neutrino-process nucleosynthesis. We discuss how to determine the suitable neutrino spectra of three different flavors and their anti-particles 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. Light-mass nuclei like 7Li and 11B, which are produced in outer He-layer, are strongly affected by the neutrino flavor oscillation due to the MSW (Mikheyev-Smirnov-Wolfenstein) effect, while heavy-mass nuclei like 138La, 180Ta and r-process elements, which are produced in the inner O-Ne-Mg layer or the atmosphere of proto-neutron star, are likely to be free from the MSW effect. Using such a different nature of the neutrino-process nucleosynthesis, we study the neutrino oscillation effects on their abundances, and propose a new novel method to determine the unknown neutrino oscillation parameters, θ13 and mass hierarchy, simultaneously. There is recent evidence that some SiC X grains from the Murchison meteorite may contain supernova-produced neutrino-process 11B and 7Li encapsulated in the grains. Combining the recent experimental constraints on θ13, we show that although the uncertainties are still large, our method hints at a marginal preference for an inverted neutrino mass hierarchy for the first time.

  19. Neutrino-nucleus cross sections for oscillation experiments

    Science.gov (United States)

    Katori, Teppei; Martini, Marco

    2018-01-01

    Neutrino oscillations physics is entering an era of high precision. In this context, accelerator-based neutrino experiments need a reduction in systematic errors to the level of a few percent. Today, one of the most important sources of systematic errors are neutrino-nucleus cross sections which, in the energy region of hundreds of MeV to a few GeV, are known to a precision not exceeding 20%. In this article we review the present experimental and theoretical knowledge of neutrino-nucleus interaction physics. After introducing neutrino-oscillation physics and accelerator-based neutrino experiments, we give an overview of general aspects of neutrino-nucleus cross sections, from both the theoretical and experimental point of view. Then, we focus on these cross sections in different reaction channels. We start with the quasi-elastic and quasi-elastic-like cross section, placing a special emphasis on the multinucleon emission channel, which has attracted a lot of attention in the last few years. We review the main aspects of the different microscopic models for this channel by discussing analogies and the differences among them. The discussion is always driven by a comparison with the experimental data. We then consider the one-pion production channel where agreement between data and theory remains highly unsatisfactory. We describe how to interpret pion data, and then analyze, in particular, the puzzle related to the difficulty of theoretical models and Monte Carlo to simultaneously describe MiniBooNE and MINERvA experimental results. Inclusive cross sections are also discussed, as well as the comparison between the {ν }μ and {ν }e cross sections, relevant for the charge-conjugation-parity violation experiments. The impact of nuclear effects on the reconstruction of neutrino energy and on the determination of the neutrino-oscillation parameters is also reviewed. Finally, we look to the future by discussing projects and efforts in relation to future detectors, beams

  20. Atmospheric neutrino oscillations, θ13 and neutrino mass hierarchy

    International Nuclear Information System (INIS)

    Bernabeu, J.; Palomares-Ruiz, Sergio; Petcov, S.T.

    2003-01-01

    We derive predictions for the Nadir angle (θ n ) dependence of the ratio N μ /N e of the rates of the μ-like and e-like multi-GeV events measured in water-Cerenkov detectors in the case of 3-neutrino oscillations of the atmospheric ν e (ν-bar e ) and ν μ (ν-bar μ ), driven by one neutrino mass squared difference, vertical bar Δm 2 31 vertical bar ∼(2.5-3.0)x10 -3 eV 2 >> Δm 2 21 . This ratio is particularly sensitive to the Earth matter effects in the atmospheric neutrino oscillations, and thus to the values of sin 2 θ 13 and sin 2 θ 23 , θ 13 and θ 23 being the neutrino mixing angle limited by CHOOZ and Palo Verde experiments and that responsible for the dominant atmospheric ν μ →ν τ (ν-bar μ →ν-bar τ ) oscillations. It is also sensitive to the type of neutrino mass spectrum which can be with normal (Δm 2 31 >0) or with inverted (Δm 2 31 2 θ 13 > or approx. 0.01, sin 2 θ 23 > or approx. 0.5 and at cosθ n > or approx. 0.4, the Earth matter effects modify substantially the θ n -dependence of the ratio N μ /N e and in a way which cannot be reproduced with sin 2 θ 13 =0 and a different value of sin 2 θ 23 . For normal hierarchy the effects can be as large as ∼25% for cosθ n ∼(0.5-0.8), can reach ∼35% in the Earth core bin cosθ n ∼(0.84-1.0), and might be observable. They are typically by ∼10% smaller in the inverted hierarchy case. An observation of the Earth matter effects in the Nadir angle distribution of the ratio N μ /N e would clearly indicate that sin 2 θ 13 > or approx. 0.01 and sin 2 θ 23 > or approx. 0.50

  1. Neutrino oscillations: The rise of the PMNS paradigm

    Science.gov (United States)

    Giganti, C.; Lavignac, S.; Zito, M.

    2018-01-01

    Since the discovery of neutrino oscillations, the experimental progress in the last two decades has been very fast, with the precision measurements of the neutrino squared-mass differences and of the mixing angles, including the last unknown mixing angle θ13. Today a very large set of oscillation results obtained with a variety of experimental configurations and techniques can be interpreted in the framework of three active massive neutrinos, whose mass and flavour eigenstates are related by a 3 × 3 unitary mixing matrix, the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) matrix, parametrized by three mixing angles θ12, θ23, θ13 and a CP-violating phase δCP. The additional parameters governing neutrino oscillations are the squared-mass differences Δ mji2 = mj2 - mi2, where mi is the mass of the ith neutrino mass eigenstate. This review covers the rise of the PMNS three-neutrino mixing paradigm and the current status of the experimental determination of its parameters. The next years will continue to see a rich program of experimental endeavour coming to fruition and addressing the three missing pieces of the puzzle, namely the determination of the octant and precise value of the mixing angle θ23, the unveiling of the neutrino mass ordering (whether m1

  2. Neutrino oscillations at LAMPF

    International Nuclear Information System (INIS)

    Carlini, R.; Choi, C.; Donohue, J.

    1985-01-01

    Work at Argonne continues on the construction of the neutrino oscillation experiment (E645). Construction of detector supports and active shield components were completed at the Provo plant of the principal contractor for the project (the Pittsburgh-Des Moines Corporation). Erection of the major experimental components was completed at the LAMPF experimental site in mid-March 1985. Work continues on the tunnel which will house the detector. Construction of detector components (scintillators and proportional drift tubes) is proceeding at Ohio State University and Louisiana State University. Consolidation of these components into the 20-ton neutrino detector is beginning at LAMPF

  3. CP violation and matter effect in long baseline neutrino oscillation experiments

    International Nuclear Information System (INIS)

    Arafune, J.; Koike, M.; Sato, J.

    1997-01-01

    We show simple methods of how to separate pure CP-violating effects from matter effects in long baseline neutrino oscillation experiments with three generations of neutrinos. We give compact formulas for neutrino oscillation probabilities assuming one of the three neutrino masses (presumably ν τ mass) to be much larger than the other masses and the effective mass due to the matter effect. Two methods are shown. One is to observe envelopes of the curves of oscillation probabilities as functions of neutrino energy; a merit of this method is that only a single detector is enough to determine the presence of CP violation. The other is to compare experiments with at least two different baseline lengths; this has the merit that it needs only a narrow energy range of oscillation data. copyright 1997 The American Physical Society

  4. Search for νμ → νe oscillations

    International Nuclear Information System (INIS)

    Godley, A.R.

    1998-01-01

    Full text: Neutrino oscillations, the changing of neutrino flavour state from one of τ, μ or e, to another, are proof of massive neutrinos, in turn pointing to Physics beyond the Standard Model, and so are of great current interest. Solar and atmospheric neutrino results suggested evidence for neutrino oscillations. Further, a tau neutrino mass of ∼ 10 eV could supply the missing mass needed to close the Universe. To satisfy the increasing interest, CERN's Neutrino Physics Program commissioned two concurrent experiments to investigate the possibility of neutrino oscillations, one of which is NOMAD, Neutrino Oscillation Magnetic Detector. NOMAD was designed to verify or deny the earlier positive neutrino oscillations results by searching for muon to tauon neutrino oscillations in accelerator neutrinos. The LSND experiment later provided evidence for muon to electron neutrino oscillations, but due to the multi-purpose design of NOMAD, it was also possible to investigate this channel. Moreover, the area of phase space being uncovered, (related to neutrino energy and oscillation length), overlaps considerably with that of LSND. An electron neutrino oscillation search involves looking for electron neutrinos in what is primarily a muon neutrino beam, with just a small contamination of electron neutrinos. It is surmised that the excess of electron neutrinos come from oscillated muon neutrinos. This type of search is called an appearance search. The principles of such a search will be detailed herein. These include a breakdown of the CERN Neutrino Beam and a method for detecting and collating different neutrino flavours at NOMAD

  5. Recent results from the Bugey neutrino oscillation experiment

    International Nuclear Information System (INIS)

    Koang, D.H.

    1984-01-01

    The energy spectrum of electron antineutrinos has been measured at two distances, 13.6 and 18.3 meters, from the core of a PWR power reactor at Bugey (France). About 63000 antineutrinos events have been recorded using the inverse β-decay reaction antiνe + p → n + e + . A significant difference in the counting rate between the two positions has been observed. The compatibility of the results with solutions in a two-neutrino oscillation analysis is discussed

  6. Electron Neutrino and Antineutrino Appearance in the MINOS Detector

    Energy Technology Data Exchange (ETDEWEB)

    Schreckenberger, Adam Paul [Univ. of Minnesota, Minneapolis, MN (United States)

    2013-04-01

    The Main Injector Neutrino Oscillation Search (MINOS) is a long-baseline neutrino experiment that utilizes a particle beam and two steel-scintillator calorimeters designed to determine the parameters associated with muon neutrino disappearance. Analysis methods developed by the MINOS νe group have facilitated the placement of limits upon the mixing angle associated with νμ → νe oscillations. Since the polarity of the focusing horns can be switched, we can perform a similar analysis with an antineutrino-enriched beam to select electron antineutrino appearance candidates. Using 3.34e20 POT (protons on target) in the antineutrino mode, we exclude θ13 = 0 at the 80% C.L. A joint fit of the 3.34e20 POT antineutrino and 10.6e20 POT neutrino samples excluded θ13 = 0 at the 96% C.L. In addition, the combined data were used to produce exclusions regarding the CP-violating phase.

  7. A Proposal for a Three Detector Short-Baseline Neutrino Oscillation Program in the Fermilab Booster Neutrino Beam

    CERN Document Server

    Antonello, M.; Bellini, V.; Benetti, P.; Bertolucci, S.; Bilokon, H.; Boffelli, F.; Bonesini, M.; Bremer, J.; Calligarich, E.; Centro, S.; Cocco, A.G.; Dermenev, A.; Falcone, A.; Farnese, C.; Fava, A.; Ferrari, A.; Gibin, D.; Gninenko, S.; Golubev, N.; Guglielmi, A.; Ivashkin, A.; Kirsanov, M.; Kisiel, J.; Kose, U.; Mammoliti, F.; Mannocchi, G.; Menegolli, A.; Meng, G.; Mladenov, D.; Montanari, C.; Nessi, M.; Nicoletto, M.; Noto, F.; Picchi, P.; Pietropaolo, F.; Plonski, P.; Potenza, R.; Rappoldi, A.; Raselli, G.L.; Rossella, M.; Rubbia, C.; Sala, P.; Scaramelli, A.; Sobczyk, J.; Spanu, M.; Stefan, D.; Sulej, R.; Sutera, C.M.; Torti, M.; Tortorici, F.; Varanini, F.; Ventura, S.; Vignoli, C.; Wachala, T.; Zani, A.; Adams, C.; Andreopoulos, C.; Ankowski, A.M.; Asaadi, J.; Bagby, L.; Baller, B.; Barros, N.; Bass, M.; Bishai, M.; Bitadze, A.; Bugel, L.; Camilleri, L.; Cavanna, F.; Chen, H.; Chi, C.; Church, E.; Cianci, D.; Collin, G.H.; Conrad, J.M.; De Geronimo, G.; Dharmapalan, R.; Djurcic, Z.; Ereditato, A.; Esquivel, J.; Evans, J.; Fleming, B.T.; Foreman, W.M.; Freestone, J.; Gamble, T.; Garvey, G.; Genty, V.; Goldi, D.; Gramellini, E.; Greenlee, H.; Guenette, R.; Hackenburg, A.; Hanni, R.; Ho, J.; Howell, J.; James, C.; Jen, C.M.; Jones, B.J.P.; Kalousis, L.N.; Karagiorgi, G.; Ketchum, W.; Klein, J.; Klinger, J.; Kreslo, I.; Kudryavtsev, V.A.; Lissauer, D.; Livesly, P.; Louis, W.C.; Luthi, M.; Mariani, C.; Mavrokoridis, K.; McCauley, N.; McConkey, N.; Mercer, I.; Miao, T.; Mills, G.B.; Montanari, D.; Moon, J.; Moss, Z.; Mufson, S.; Norris, B.; Nowak, J.; Pal, S.; Palamara, O.; Pater, J.; Pavlovic, Z.; Perkin, J.; Pulliam, G.; Qian, X.; Qiuguang, L.; Radeka, V.; Rameika, R.; Ratoff, P.N.; Richardson, M.; von Rohr, C.Rudolf; Russell, B.; Schmitz, D.W.; Shaevitz, M.H.; Sippach, B.; Soderberg, M.; Soldner-Rembold, S.; Spitz, J.; Spooner, N.; Strauss, T.; Szelc, A.M.; Taylor, C.E.; Terao, K.; Thiesse, M.; Thompson, L.; Thomson, M.; Thorn, C.; Toups, M.; Touramanis, C.; Van de Water, R.G.; Weber, M.; Whittington, D.; Wongjirad, T.; Yu, B.; Zeller, G.P.; Zennamo, J.; Acciarri, R.; An, R.; Barr, G.; Blake, A.; Bolton, T.; Bromberg, C.; Caratelli, D.; Carls, B.; Convery, M.; Dytmam, S.; Eberly, B.; Gollapinni, S.; Graham, M.; Grosso, R.; Hen, O.; Hewes, J.; Horton-Smith, G.; Johnson, R.A.; Joshi, J.; Jostlein, H.; Kaleko, D.; Kirby, B.; Kirby, M.; Kobilarcik, T.; Li, Y.; Littlejohn, B.; Lockwitz, S.; Lundberg, B.; Marchionni, A.; Marshall, J.; McDonald, K.; Meddage, V.; Miceli, T.; Mooney, M.; Moulai, M.H.; Murrells, R.; Naples, D.; Nienaber, P.; Paolone, V.; Papavassiliou, V.; Pate, S.; Pordes, S.; Raaf, J.L.; Rebel, B.; Rochester, L.; Schukraft, A.; Seligman, W.; St. John, J.; Tagg, N.; Tsai, Y.; Usher, T.; Wolbers, S.; Woodruff, K.; Xu, M.; Yang, T.; Zhang, C.; Badgett, W.; Biery, K.; Brice, S.J.; Dixon, S.; Geynisman, M.; Moore, C.; Snider, E.; Wilson, P.

    2015-01-01

    A Short-Baseline Neutrino (SBN) physics program of three LAr-TPC detectors located along the Booster Neutrino Beam (BNB) at Fermilab is presented. This new SBN Program will deliver a rich and compelling physics opportunity, including the ability to resolve a class of experimental anomalies in neutrino physics and to perform the most sensitive search to date for sterile neutrinos at the eV mass-scale through both appearance and disappearance oscillation channels. Using data sets of 6.6e20 protons on target (P.O.T.) in the LAr1-ND and ICARUS T600 detectors plus 13.2e20 P.O.T. in the MicroBooNE detector, we estimate that a search for muon neutrino to electron neutrino appearance can be performed with ~5 sigma sensitivity for the LSND allowed (99% C.L.) parameter region. In this proposal for the SBN Program, we describe the physics analysis, the conceptual design of the LAr1-ND detector, the design and refurbishment of the T600 detector, the necessary infrastructure required to execute the program, and a possible...

  8. Effects of neutrino oscillations on the supernova signal in LVD

    International Nuclear Information System (INIS)

    Aglietta, M.; Antonioli, P.; Bari, G.; Castagnoli, C.; Fulgione, W.; Galeotti, P.; Ghia, P.L.; Giusti, P.; Kemp, E.; Malguin, A.S.; Nurzia, G.; Pesci, A.; Picchi, P.; Pless, I.A.; Ryasny, V.G.; Ryazhskaya, O.G.; Sartorelli, G.; Selvi, M.; Vigorito, C.; Vissani, F.; Votano, L.; Yakushev, V.F.; Zatsepin, G.T.; Zichichi, A.

    2002-01-01

    We study the impact of neutrino oscillations on the supernova neutrino signal in the Large Volume Detector (LVD). The number of expected events for a galactic supernova (D = 10 kpc) is calculated, assuming neutrino masses and mixing that explain solar and atmospheric neutrino results. The possibility to detect neutrinos in different channels makes LVD sensitive to different scenarios for ν properties, such as normal or inverted ν mass hierarchy, and/or adiabatic or non adiabatic MSW resonances associated to U e3 . Of particular importance are the charged current (c.c.) reactions on 12 C: oscillations increase by almost one order of magnitude the number of events expected from this channel

  9. Movement of the pulsars and neutrino oscillations; Movimiento de los pulsares y oscilaciones de neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Barkovich, M.A

    2005-07-01

    The astronomical observations show that the pulsars are not in the center of the remainder of the supernovae that gave its origin, but rather are displaced of the same one and moving to a speed of about 500 km/s, which is much bigger that of the progenitor star. This fact constitutes a strong evidence that the pulsars is accelerated in the moment of its birth and by this it is denominated to this phenomenon 'pulsars kick'. They exist numerous and varied mechanisms to explain this effect, but none makes it in way completely satisfactory. In this thesis we will study in detail a mechanism proposed originally by Kusenko and Segre and that is based on an asymmetric emission of the neutrinos flow induced by the oscillations of the same ones when its spread in a magnetized media. For this end we will develop, in first instance, the Eddington model. This is based on the transport of the neutrino flux and it describes in a reasonable way the atmosphere of a neutron protostar, place where take place the oscillations. Next we will study the problem of the emission of a neutrino gas from a resonance volume. These results will be applied to the study of the kick in the cases of oscillations among active neutrinos and actives with sterile to determine the magnetic field and the oscillation parameters (difference of the square of the masses of those neutrinos and mixture angle in vacuum) required. Finally we will analyze those neutrino oscillations induced by a possible violation of the Equivalence principle and it implication in the pulsars dynamics. (Author)

  10. Supernova relic electron neutrinos and anti-neutrinos in future large-scale observatories

    Energy Technology Data Exchange (ETDEWEB)

    Volpe, C.; Welzel, J. [Institut de Physique Nuclueaire, 91 - Orsay (France)

    2007-07-01

    We investigate the signal from supernova relic neutrinos in future large scale observatories, such as MEMPHYS (UNO, Hyper-K), LENA and GLACIER, at present under study. We discuss that complementary information might be gained from the observation of supernova relic electron antineutrinos and neutrinos using the scattering on protons on one hand, and on nuclei such as oxygen, carbon or argon on the other hand. When determining the relic neutrino fluxes we also include, for the first time, the coupling of the neutrino magnetic moment to magnetic fields within the core collapse supernova. We present numerical results on both the relic {nu}{sub e} and {nu}-bar{sub e} fluxes and on the number of events for {nu}{sub e} + C{sup 12}, {nu}{sub e} + O{sup 16}, {nu}{sub e} + Ar{sup 40} and {nu}-bar{sub e} + p for various oscillation scenarios. The observation of supernova relic neutrinos might provide us with unique information on core-collapse supernova explosions, on the star formation history and on neutrino properties, that still remain unknown. (authors)

  11. Atmospheric neutrino oscillations from upward throughgoing muon multiple scattering in MACRO

    Energy Technology Data Exchange (ETDEWEB)

    Ambrosio, M.; Antolini, R.; Bakari, D.; Baldini, A.; Barbarino, G.C.; Barish, B.C.; Battistoni, G.; Becherini, Y.; Bellotti, R.; Bemporad, C.; Bernardini, P.; Bilokon, H.; Bloise, C.; Bower, C.; Brigida, M.; Bussino, S.; Cafagna, F.; Calicchio, M.; Campana, D.; Carboni, M.; Caruso, R.; Cecchini, S.; Cei, F.; Chiarella, V.; Chiarusi, T.; Choudhary, B.C.; Coutu, S.; Cozzi, M.; De Cataldo, G.; Dekhissi, H.; De Marzo, C.; De Mitri, I.; Derkaoui, J.; De Vincenzi, M.; Di Credico, A.; Favuzzi, C.; Forti, C.; Fusco, P.; Giacomelli, G.; Giannini, G.; Giglietto, N.; Giorgini, M.; Grassi, M.; Grillo, A.; Gustavino, C.; Habig, A.; Hanson, K.; Heinz, R.; Iarocci, E.; Katsavounidis, E.; Katsavounidis, I.; Kearns, E.; Kim, H.; Kumar, A.; Kyriazopoulou, S.; Lamanna, E.; Lane, C.; Levin, D.S.; Lipari, P.; Longo, M.J.; Loparco, F.; Maaroufi, F.; Mancarella, G.; Mandrioli, G.; Manzoor, S.; Margiotta, A.; Marini, A.; Martello, D.; Marzari-Chiesa, A.; Mazziotta, M.N.; Michael, D.G.; Mikheyev, S.; Monacelli, P.; Montaruli, T.; Monteno, M.; Mufson, S.; Musser, J.; Nicolo, D.; Nolty, R.; Orth, C.; Osteria, G.; Palamara, O.; Patera, V.; Patrizii, L.; Pazzi, R.; Peck, C.W.; Perrone, L.; Petrera, S.; Popa, V.; Raino, A.; Reynoldson, J.; Ronga, F.; Rrhioua, A.; Satriano, C.; Scapparone, E.; Scholberg, K.; Sciubba, A.; Serra, P.; Sioli, M.; Sirri, G.; Sitta, M.; Spinelli, P.; Spinetti, M.; Spurio, M.; Steinberg, R.; Stone, J.L.; Sulak, L.R.; Surdo, A.; Tarle, G.; Togo, V.; Vakili, M.; Walter, C.W.; Webb, R

    2003-07-24

    The energy of atmospheric neutrinos detected by MACRO was estimated using multiple Coulomb scattering of upward throughgoing muons. This analysis allows a test of atmospheric neutrino oscillations, relying on the distortion of the muon energy distribution. These results have been combined with those coming from the upward throughgoing muon angular distribution only. Both analyses are independent of the neutrino flux normalization and provide strong evidence, above the 4{sigma} level, in favour of neutrino oscillations.

  12. Measurement of Long Baseline Neutrino Oscillations and Improvements from Deep Learning

    Energy Technology Data Exchange (ETDEWEB)

    Psihas, Fernanda [Indiana U.

    2018-01-01

    NOvA is a long-baseline neutrino oscillation experiment which measures the oscillation of muon neutrinos from the NuMI beam at Fermilab after they travel through the Earth for 810 km. In this dissertation I describe the operations and monitoring of the detectors which make it possible to record over 98% of the delivered neutrino beam. I also present reconstruction and identification techniques using deep convolutional neural networks (CNNs), which are applicable to multiple analyses. Lastly, I detail the oscillation analyses in the $\

  13. Addendum to "Compact Perturbative Expressions for Neutrino Oscillations in Matter"

    Energy Technology Data Exchange (ETDEWEB)

    Denton, Peter B. [Bohr Inst.; Minakata, Hisakazu [CSIC, Madrid; Parke, Stephen J. [Fermilab

    2018-01-19

    In this paper we rewrite the neutrino mixing angles and mass squared differences in matter given, in our original paper, in a notation that is more conventional for the reader. Replacing the usual neutrino mixing angles and mass squared differences in the expressions for the vacuum oscillation probabilities with these matter mixing angles and mass squared differences gives an excellent approximation to the oscillation probabilities in matter. Comparisons for T2K, NOvA, T2HKK and DUNE are also given for neutrinos and anti-neutrinos, disappearance and appearance channels, normal ordering and inverted ordering.

  14. (g-2)μ anomaly and neutrino oscillations within the left-right model

    International Nuclear Information System (INIS)

    Boyarkin, O.M.; Bakanova, T.I.

    2003-12-01

    The Higgs sector structure of the left right model is investigated. The coupling constants of the physical Higgs bosons are expressed in terms of the oscillation parameters of the heavy neutrinos. The electroweak corrections to the value of the anomalous magnetic moment of the muon coming from the Higgs bosons axe found. It is shown that in the LRM the motion of the light neutrino flux in matter is described within the hybrid three-neutrino scheme, namely, the neutrino oscillations and the non standard neutrino interactions, caused by the Higgs sector. These non standard contributions may considerably change the matter potential compared with the SM prediction. Therefore, the analysis of the (g-2)μ, anomaly and the oscillations of the light neutrinos in matter could be used to constrain the parameters of the heavy neutrinos. (author)

  15. Analytical treatment of neutrino asymmetry equilibration from flavor oscillations in the early universe

    Science.gov (United States)

    Wong, Yvonne Y.

    2002-07-01

    A recent numerical study by A. D. Dolgov, S. H. Hansen, S. Pastor, S. T. Petcov, G. G. Raffelt, and D. V. Semikoz (DHPPRS) [Nucl. Phys. B632, 363 (2002)] found that complete or partial equilibrium between all active neutrino flavors can be achieved before the big bang nucleosynthesis epoch via flavor oscillations, if the oscillation parameters are those inferred from the atmospheric and solar neutrino data, and, in some cases, if θ13 is also sizable. As such, cosmological constraints on the electron neutrino-antineutrino asymmetry are now applicable in all three neutrino sectors. In the present work, we provide an analytical treatment of the scenarios considered in DHPPRS, and demonstrate that their results are stable even for very large initial asymmetries. The equilibration mechanism can be understood in terms of a Mikheyev-Smirnov-Wolfenstein-like effect for a maximally mixed and effectively monochromatic system. We also comment on the DHPPRS's choices of mixing parameters, and their handling of collisional effects, both of which could impinge on the extent of flavor equilibrium.

  16. The influence of collective neutrino oscillations on a supernova r process

    Science.gov (United States)

    Duan, Huaiyu; Friedland, Alexander; McLaughlin, Gail C.; Surman, Rebecca

    2011-03-01

    Recently, it has been demonstrated that neutrinos in a supernova oscillate collectively. This process occurs much deeper than the conventional matter-induced Mikheyev-Smirnov-Wolfenstein effect and hence may have an impact on nucleosynthesis. In this paper we explore the effects of collective neutrino oscillations on the r-process, using representative late-time neutrino spectra and outflow models. We find that accurate modeling of the collective oscillations is essential for this analysis. As an illustration, the often-used 'single-angle' approximation makes grossly inaccurate predictions for the yields in our setup. With the proper multiangle treatment, the effect of the oscillations is found to be less dramatic, but still significant. Since the oscillation patterns are sensitive to the details of the emitted fluxes and the sign of the neutrino mass hierarchy, so are the r-process yields. The magnitude of the effect also depends sensitively on the astrophysical conditions—in particular on the interplay between the time when nuclei begin to exist in significant numbers and the time when the collective oscillation begins. A more definitive understanding of the astrophysical conditions, and accurate modeling of the collective oscillations for those conditions, is necessary.

  17. Dissipative neutrino oscillations in randomly fluctuating matter

    International Nuclear Information System (INIS)

    Benatti, F.; Floreanini, R.

    2005-01-01

    The generalized dynamics describing the propagation of neutrinos in randomly fluctuating media is analyzed: It takes into account matter-induced, decoherence phenomena that go beyond the standard Mikheyev-Smirnov-Wolfenstein (MSW) effect. A widely adopted density fluctuation pattern is found to be physically untenable: A more general model needs to be instead considered, leading to flavor changing effective neutrino-matter interactions. They induce new, dissipative effects that modify the neutrino oscillation pattern in a way amenable to a direct experimental analysis

  18. Dissipative neutrino oscillations in randomly fluctuating matter

    Science.gov (United States)

    Benatti, F.; Floreanini, R.

    2005-01-01

    The generalized dynamics describing the propagation of neutrinos in randomly fluctuating media is analyzed: It takes into account matter-induced, decoherence phenomena that go beyond the standard Mikheyev-Smirnov-Wolfenstein (MSW) effect. A widely adopted density fluctuation pattern is found to be physically untenable: A more general model needs to be instead considered, leading to flavor changing effective neutrino-matter interactions. They induce new, dissipative effects that modify the neutrino oscillation pattern in a way amenable to a direct experimental analysis.

  19. Measurement of electron neutrino appearance with the MINOS experiment

    International Nuclear Information System (INIS)

    Boehm, Joshua Adam Alpern

    2009-01-01

    MINOS is a long-baseline two-detector neutrino oscillation experiment that uses a high intensity muon neutrino beam to investigate the phenomena of neutrino oscillations. By measuring the neutrino interactions in a detector near the neutrino source and again 735 km away from the production site, it is possible to probe the parameters governing neutrino oscillation. The majority of the ν μ oscillate to ν τ but a small fraction may oscillate instead to ν e . This thesis presents a measurement of the ν e appearance rate in the MINOS far detector using the first two years of exposure. Methods for constraining the far detector backgrounds using the near detector measurements is discussed and a technique for estimating the uncertainty on the background and signal selection are developed. A 1.6σ excess over the expected background rate is found providing a hint of ν e appearance.

  20. Extrinsic CPT Violation in Neutrino Oscillations

    International Nuclear Information System (INIS)

    Ohlsson, Tommy

    2004-01-01

    In this talk, we investigate extrinsic CPT violation in neutrino oscillations in matter with three flavors. Note that extrinsic CPT violation is different from intrinsic CPT violation. Extrinsic CPT violation is one way of quantifying matter effects, whereas intrinsic CPT violation would mean that the CPT invariance theorem is not valid. We present analytical formulas for the extrinsic CPT probability differences and discuss their implications for long-baseline experiments and neutrino factory setups

  1. Measurement of the Charged-Current Quasi-Elastic Cross-Section for Electron Neutrinos on a Hydrocarbon Target

    Energy Technology Data Exchange (ETDEWEB)

    Wolcott, Jeremy [Univ. of Rochester, NY (United States)

    2016-01-01

    Appearance-type neutrino oscillation experiments, which observe the transition from muon neutrinos to electron neutrinos, promise to help answer some of the fundamental questions surrounding physics in the post-Standard-Model era. Because they wish to observe the interactions of electron neutrinos in their detectors, and because the power of current results is typically limited by their systematic uncertainties, these experiments require precise estimates of the cross-section for electron neutrino interactions. Of particular interest is the charged-current quasi-elastic (CCQE) process, which gures signi cantly in the composition of the reactions observed at the far detector. However, no experimental measurements of this crosssection currently exist for electron neutrinos; instead, current experiments typically work from the abundance of muon neutrino CCQE cross-section data and apply corrections from theoretical arguments to obtain a prediction for electron neutrinos. Veri cation of these predictions is challenging due to the di culty of constructing an electron neutrino beam, but the advent of modern high-intensity muon neutrino beams|together with the percent-level electron neutrino impurity inherent in these beams| nally presents the opportunity to make such a measurement. We report herein the rst-ever measurement of a cross-section for an exclusive state in electron neutrino scattering, which was made using the MINER A detector in the NuMI neutrino beam at Fermilab. We present the electron neutrino CCQE di erential cross-sections, which are averaged over neutrinos of energies 1-10 GeV (with mean energy of about 3 GeV), in terms of various kinematic variables: nal-state electron angle, nal-state electron energy, and the square of the fourmomentum transferred to the nucleus by the neutrino , Q2. We also provide a total cross-section vs. neutrino energy. While our measurement of this process is found to be in agreement with the predictions of the GENIE

  2. Supernova constraints on neutrino oscillation and EoS for proto-neutron star

    Energy Technology Data Exchange (ETDEWEB)

    Kajino, T. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan and Department of Astronomy, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033 (Japan); Aoki, W. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Cheoun, M.-K. [Department of Physics, Soongsil University, Seoul 156-743 (Korea, Republic of); Hayakawa, T. [Japan Atomic Energy Agency, Shirakara-Shirane 2-4, Tokai-mura, Ibaraki 319-1195 (Japan); Hidaka, J. [National Astronomical Observatory, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Hirai, Y.; Shibagaki, S. [National Astronomical Observatory, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan and Department of Astronomy, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033 (Japan); Mathews, G. J. [Department of Physics, University of Notre Dame, IN 46556 (United States); Nakamura, K. [Waseda University, Ohkubo 3-4-1, Shinjuku, Tokyo 169-8555 (Japan); Suzuki, T. [Nihon University, Sakurajosui 3-25-40, Setagaya-ku, Tokyo 156-8550 (Japan)

    2014-05-02

    Core-collapse supernovae eject huge amount of flux of energetic neutrinos which affect explosive nucleosynthesis of rare isotopes like {sup 7}Li, {sup 11}B, {sup 92}Nb, {sup 138}La and Ta and r-process elements. Several isotopes depend strongly on the neutrino flavor oscillation due to the Mikheyev-Smirnov-Wolfenstein (MSW) effect. We here discuss how to determine the neutrino temperatures and propose a method to determine still unknown neutrino oscillation parameters, mass hierarchy and θ{sub 13}, simultaneously. Combining the recent experimental constraints on θ{sub 13} with isotopic ratios of the light elements discovered in presolar grains from the Murchison meteorite, we show that our method suggests at a marginal preference for an inverted neutrino mass hierarchy. We also 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.

  3. Supernova constraints on neutrino oscillation and EoS for proto-neutron star

    Science.gov (United States)

    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 which affect explosive nucleosynthesis of rare isotopes like 7Li, 11B, 92Nb, 138La and Ta and r-process elements. Several isotopes depend strongly on the neutrino flavor oscillation due to the Mikheyev-Smirnov-Wolfenstein (MSW) effect. We here discuss how to determine the neutrino temperatures and propose a method to determine still unknown neutrino oscillation parameters, mass hierarchy and θ13, simultaneously. Combining the recent experimental constraints on θ13 with isotopic ratios of the light elements discovered in presolar grains from the Murchison meteorite, we show that our method suggests at a marginal preference for an inverted neutrino mass hierarchy. We also 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.

  4. Exploration of possible quantum gravity effects with neutrinos I: Decoherence in neutrino oscillations experiments

    International Nuclear Information System (INIS)

    Sakharov, Alexander; Mavromatos, Nick; Sarkar, Sarben; Meregaglia, Anselmo; Rubbia, Andre

    2009-01-01

    Quantum gravity may involve models with stochastic fluctuations of the associated metric field, around some fixed background value. Such stochastic models of gravity may induce decoherence for matter propagating in such fluctuating space time. In most cases, this leads to fewer neutrinos of all active flavours being detected in a long baseline experiment as compared to three-flavour standard neutrino oscillations. We discuss the potential of the CNGS and J-PARC beams in constraining models of quantum-gravity induced decoherence using neutrino oscillations as a probe. We use as much as possible model-independent parameterizations, even though they are motivated by specific microscopic models, for fits to the expected experimental data which yield bounds on quantum-gravity decoherence parameters.

  5. Measurement of electron neutrino appearance with the MINOS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, Joshua Adam Alpern [Harvard Univ., Cambridge, MA (United States)

    2009-05-01

    MINOS is a long-baseline two-detector neutrino oscillation experiment that uses a high intensity muon neutrino beam to investigate the phenomena of neutrino oscillations. By measuring the neutrino interactions in a detector near the neutrino source and again 735 km away from the production site, it is possible to probe the parameters governing neutrino oscillation. The majority of the vμ oscillate to vτ but a small fraction may oscillate instead to ve. This thesis presents a measurement of the ve appearance rate in the MINOS far detector using the first two years of exposure. Methods for constraining the far detector backgrounds using the near detector measurements is discussed and a technique for estimating the uncertainty on the background and signal selection are developed. A 1.6σ excess over the expected background rate is found providing a hint of ve appearance.

  6. Inner conductor of the magnetic double-horn for the neutrino oscillation experiment with BEBC

    CERN Multimedia

    CERN PhotoLab

    1982-01-01

    In 1980 renewed interest arose in probing for neutrino non-zero masses and associated neutrino oscillations. Low-energy muon-neutrino beams (produced with a proton beam from the PS) were directed towards the SPS neutrino detectors, BEBC, WA1 and WA18 (Annual Report 1982, p.43, Fig.13). Experiments PS169 (WA1) and PS181 (WA18) were "disappearence" experiments and used a "bare" production target, whereas experiment PS180 (BEBC), looked for electron-neutrino "appearence" and used a horn-focused beam. The manufacture of the inner conductor of the double-horn (a particular breed of current-sheet lens) required exceedingly delicate machining. For further pictures see 8304055 and Annual Report 1982, p.137; and p.43 for a description of the experiments.

  7. Neutrino oscillations: An essay in honor of Felix Boehm

    International Nuclear Information System (INIS)

    Rosen, S.P.

    1989-01-01

    We briefly review the theory of neutrino oscillations and the MSW effect and report on new calculations by Rosen and Gelb for solar neutrino-electron scattering. The aim of these calculations is to try to use the scattering process as a means of choosing between the three types of MSW solutions for the 37 Cl experiment. Both the efficiency and the resolution of the Kamiokande II detector are taken into account and the ratio R of the MSW prediction to the standard solar model prediction is calculated for different cuts on the minimum electron energy. We find that the adiabatic solution requires R to be less than 1/3, the large angle one requires it to be less than 2/3, and the nonadiabatic one restricts it to a value close to 1/2. The central value of the published KII data is close to 1/2, but the errors are too large to exclude the other solutions. 20 refs., 1 fig

  8. Investigation of matter enhanced neutrino oscillations relevant to the solar neutrino problem

    International Nuclear Information System (INIS)

    Losecco, J.M.; Bionta, R.M.; Casper, D.; Claus, R.; Errede, S.; Foster, G.; Park, H.S.; Seidel, S.; Shumard, E.; Sinclair, D.; Stone, J.L.; Sulak, L.; Van der Velde, J.C.; Blewitt, G.; Cortez, B.; Lehmann, E.; Bratton, C.B.; Gajewski, W.; Ganezer, K.S.; Haines, T.J.; Kropp, W.R.; Reines, F.; Schultz, J.; Sobel, H.W.; Wuest, C.; Goldhaber, M.; Jones, T.W.; Kielczewska, D.; Learned, J.G.; Svoboda, R.

    1987-01-01

    We study the effect of matter enhanced neutrino oscillations on atmospheric neutrinos. A recently proposed solution to the solar neutrino problem with Δm 2 =1.1x10 -4 eV 2 suggests enhanced effects in the range 200 MeV-500 MeV. We find no evidence of this effect for ν μ ??ν e mixing. Limits are set on the magnitude of the mixing angle. Our limit is sin θ V <0.14 at 90% confidence level. The limit is dominated by statistical errors and may be improved. (orig.)

  9. The not-so-sterile 4th neutrino: constraints on new gauge interactions from neutrino oscillation experiments

    Science.gov (United States)

    Kopp, Joachim; Welter, Johannes

    2014-12-01

    Sterile neutrino models with new gauge interactions in the sterile sector are phenomenologically interesting since they can lead to novel effects in neutrino oscillation experiments, in cosmology and in dark matter detectors, possibly even explaining some of the observed anomalies in these experiments. Here, we use data from neutrino oscillation experiments, in particular from MiniBooNE, MINOS and solar neutrino experiments, to constrain such models. We focus in particular on the case where the sterile sector gauge boson A ' couples also to Standard Model particles (for instance to the baryon number current) and thus induces a large Mikheyev-Smirnov-Wolfenstein potential. For eV-scale sterile neutrinos, we obtain strong constraints especially from MINOS, which restricts the strength of the new interaction to be less than ˜ 10 times that of the Standard Model weak interaction unless active-sterile neutrino mixing is very small (sin2 θ 24 ≲ 10-3). This rules out gauge forces large enough to affect short-baseline experiments like MiniBooNE and it imposes nontrivial constraints on signals from sterile neutrino scattering in dark matter experiments.

  10. Expressions for neutrino wave functions and transition probabilities at three-neutrino oscillations in vacuum and some of their applications

    International Nuclear Information System (INIS)

    Beshtoev, Kh.M.

    2006-01-01

    I have considered three-neutrino vacuum transitions and oscillations in the general case and obtained expressions for neutrino wave functions in three cases: with CP violation, without CP violation and in the case when direct ν e - ν τ transitions are absent β(θ 13 ) = 0 (some works indicate this possibility). Then using the existing experimental data some analysis has been fulfilled. This analysis definitely has shown that direct transitions ν e - ν τ cannot be closed for the Solar neutrinos, i. e., β(θ 13 ) ≠ 0. It is also shown that the possibility that β(θ 13 ) = 0 cannot be realized by using the mechanism of resonance enhancement of neutrino oscillations in matter (the Sun). It was found out that the probability of ν e - ν e neutrino transitions is a positive defined value, if in reality neutrino oscillations take place, only if the angle of ν e , ν τ mixing β ≤ 15 - 17 deg

  11. Quantum field-theoretical description of neutrino and neutral kaon oscillations

    Science.gov (United States)

    Volobuev, Igor P.

    2018-05-01

    It is shown that the neutrino and neutral kaon oscillation processes can be consistently described in quantum field theory using only plane waves of the mass eigenstates of neutrinos and neutral kaons. To this end, the standard perturbative S-matrix formalism is modified so that it can be used for calculating the amplitudes of the processes passing at finite distances and finite time intervals. The distance-dependent and time-dependent parts of the amplitudes of the neutrino and neutral kaon oscillation processes are calculated and the results turn out to be in accordance with those of the standard quantum mechanical description of these processes based on the notion of neutrino flavor states and neutral kaon states with definite strangeness. However, the physical picture of the phenomena changes radically: now, there are no oscillations of flavor or definite strangeness states, but, instead of it, there is interference of amplitudes due to different virtual mass eigenstates.

  12. Phenomenology of neutrino oscillations at the neutrino factory

    International Nuclear Information System (INIS)

    Tang, Jian

    2011-01-01

    We consider the prospects for a neutrino factory measuring mixing angles, the CP violating phase and mass-squared differences by detecting wrong-charge muons arising from the chain μ + → ν e → ν μ → μ - and the right-charge muons coming from the chain μ + → anti ν μ → anti ν μ → μ - (similar to μ - chains), where ν e → ν μ and anti ν μ → anti ν μ are neutrino oscillation channels through a long baseline. First, we study physics with near detectors and consider the treatment of systematic errors including cross section errors, flux errors, and background uncertainties. We illustrate for which measurements near detectors are required, discuss how many are needed, and what the role of the flux monitoring is. We demonstrate that near detectors are mandatory for the leading atmospheric parameter measurements if the neutrino factory has only one baseline, whereas systematic errors partially cancel if the neutrino factory complex includes the magic baseline. Second, we perform the baseline and energy optimization of the neutrino factory including the latest simulation results from the magnetized iron neutrino detector (MIND). We also consider the impact of τ decays, generated by appearance channels ν μ → ν τ and ν e → ν τ , on the discovery reaches of the mass orderings, the leptonic CP violation, and the non-zero θ 13 , which we find to be negligible for the considered detector. Third, we make a comparison of a high energy neutrino factory to a low energy neutrino factory and find that they are just two versions of the same experiment optimized for different regions of the parameter space. In addition, we briefly comment on whether it is useful to build the bi-magic baseline at the low energy neutrino factory. Finally, the effects of one additional massive sterile neutrino are discussed in the context of a combined short and long baseline setup. It is found that near detectors can provide the required sensitivity at the

  13. Collective three-flavor oscillations of supernova neutrinos

    Science.gov (United States)

    Dasgupta, Basudeb; Dighe, Amol

    2008-06-01

    Neutrinos and antineutrinos emitted from a core collapse supernova interact among themselves, giving rise to collective flavor conversion effects that are significant near the neutrinosphere. We develop a formalism to analyze these collective effects in the complete three-flavor framework. It naturally generalizes the spin-precession analogy to three flavors and is capable of analytically describing phenomena like vacuum/Mikheyev-Smirnov-Wolfenstein (MSW) oscillations, synchronized oscillations, bipolar oscillations, and spectral split. Using the formalism, we demonstrate that the flavor conversions may be “factorized” into two-flavor oscillations with hierarchical frequencies. We explicitly show how the three-flavor solution may be constructed by combining two-flavor solutions. For a typical supernova density profile, we identify an approximate separation of regions where distinctly different flavor conversion mechanisms operate, and demonstrate the interplay between collective and MSW effects. We pictorialize our results in terms of the “e3-e8 triangle” diagram, which is a tool that can be used to visualize three-neutrino flavor conversions in general, and offers insights into the analysis of the collective effects in particular.

  14. First Anti-neutrino Oscillation Results from the T2K Experiment

    CERN Multimedia

    CERN. Geneva

    2015-01-01

    Neutrinos are some of the most abundant but yet most elusive particles in the universe. They have almost no mass, only interact weakly and relatively little is known about their properties. Furthermore it has been firmly established over the last decade that neutrinos can undergo flavour transitions as mass and flavor eigenstates are not identical. These neutrino oscillations have been studied using natural sources as well as nuclear reactors or with neutrinos produced at accelerators. T2K is a long baseline neutrino oscillation beam that uses a beam of muon (anti-)neutrinos that is directed form J-PARC at the east cost of Japan over a distance of almost 300 km to the SuperKamiokande water Cherenkov detector in the west. The facility is complemented by a near detector complex 280 m downstream of the neutrino production target to characterise the beam and the neutrino interaction dynamics. T2K has taken data with a muon neutrino beam since early 2010 and is studying the disappearance of muon neutrinos as well...

  15. Highlights from e-EPS: Neutrino Oscillation / DPG President / Outreach Database

    CERN Multimedia

    2012-01-01

    e-EPS News is a monthly addition to the CERN Bulletin line-up, showcasing articles from e-EPS – the European Physical Society newsletter – as part of a collaboration between the two publications.   Asian experiments unlock neutrino oscillation mystery Two reactor experiments, China’s Daya Bay and Korea’s RENO, have made the best measurement of the neutrino mixing angle, θ13, an essential property for neutrino research. The discovery of a non-zero θ13 at approximately 9˚ – which was published in March and April this year – completes our picture of neutrino mixing. This quite large value for the mixing angle will make it easier to conduct future long baseline neutrino experiments. This, in turn, may lead to a better understanding of the matter-antimatter asymmetry seen in the Universe. Neutrino oscillations – the change in flavour&a...

  16. Probing CPT violation in neutrino oscillation: A three flavor analysis

    International Nuclear Information System (INIS)

    Samanta, Abhijit

    2010-01-01

    We have studied CPT violation in neutrino oscillation considering three flavor framework with matter effect. We have constructed a new way to find the oscillation probability incorporating CPT violating terms without any approximation. Then CPT violation with atmospheric neutrinos for a magnetized iron calorimeter detector considering the muons (directly measurable with high resolution) of the charge current events has been studied for zero and nonzero θ 13 values. It is found that a potential bound of δb 32 ≤6x10 -24 GeV at 99% CL can be obtained with 1 Mton.year exposure of this detector; and unlike neutrino beam experiments, there is no possibility to generate 'fake' CPT violation due to matter effect with atmospheric neutrinos. The advantages of atmospheric neutrinos to discriminate CPT violation from CP violation and nonstandard interactions are also discussed.

  17. Vacuum oscillation solution to the solar neutrino problem in standard and nonstandard pictures

    International Nuclear Information System (INIS)

    Berezhiani, Z.G.; Rossi, A.

    1995-01-01

    The neutrino long wavelength (just-so) oscillation is reexamined as a solution to the solar neutrino problem. We consider the just-so scenario in various cases: in the framework of the solar models with a relaxed prediction of the boron neutrino flux, as well as in the presence of the nonstandard weak range interactions between neutrino and matter constituents. We show that the fit of the experimental data in the just-so scenario is not very good for any reasonable value of the 8 B neutrino flux, but it substantially improves if the nonstandard τ-neutrino--electron interaction is included. These new interactions could also remove the conflict of the just-so picture with the shape of the SN 1987A neutrino spectrum. Special attention is devoted to the potential of the future real-time solar neutrino detectors such as Super-Kamiokande, SNO, and BOREXINO, which could provide the model-independent tests for the just-so scenario. In particular, these imply a specific deformation of the original solar neutrino energy spectra and time variation of the intermediate energy monochromatic neutrino ( 7 Be and pep) signals

  18. Measuring neutrino oscillation parameters using νμ disappearance in MINOS

    International Nuclear Information System (INIS)

    Backhouse, Christopher James

    2011-01-01

    MINOS is a long-baseline neutrino oscillation experiment. It consists of two large steel-scintillator tracking calorimeters. The near detector is situated at Fermilab, close to the production point of the NuMI muon-neutrino beam. The far detector is 735 km away, 716m underground in the Soudan mine, Northern Minnesota. The primary purpose of the MINOS experiment is to make precise measurements of the 'atmospheric' neutrino oscillation parameters (Δm atm 2 and sin 2 2θ atm ). The oscillation signal consists of an energy-dependent deficit of ν μ interactions in the far detector. The near detector is used to characterize the properties of the beam before oscillations develop. The two-detector design allows many potential sources of systematic error in the far detector to be mitigated by the near detector observations. This thesis describes the details of the ν μ -disappearance analysis, and presents a new technique to estimate the hadronic energy of neutrino interactions. This estimator achieves a significant improvement in the energy resolution of the neutrino spectrum, and in the sensitivity of the neutrino oscillation fit. The systematic uncertainty on the hadronic energy scale was re-evaluated and found to be comparable to that of the energy estimator previously in use. The best-fit oscillation parameters of the ν μ -disappearance analysis, incorporating this new estimator were: Δm 2 = 2.32 -0.08 +0.12 x 10 -3 eV 2 , sin 2 2θ > 0.90 (90% C.L.). A similar analysis, using data from a period of running where the NuMI beam was operated in a configuration producing a predominantly (bar ν) μ beam, yielded somewhat different best-fit parameters Δ(bar m) 2 = (3.36 -0.40 +0.46 (stat.) ± 0.06(syst.)) x 10 -3 eV 2 , sin 2 2(bar θ) = 0.86 -0.12 0 .11 (stat.) ± 0.01(syst.). The tension between these results is intriguing, and additional antineutrino data is currently being taken in order to further investigate this apparent discrepancy.

  19. Puzzle of "lost" reactor neutrinos solved by scientists

    CERN Multimedia

    2002-01-01

    A collaboration of Chinese, Japanese and American scientists have announced that electron antineutrinos from nuclear reactors escape detection by oscillating into another type of neutrino. The experiment confirms solar neutrino oscillation and determines the key parameters of neutrino oscillation (1/2 page).

  20. An accurate analytic description of neutrino oscillations in matter

    Science.gov (United States)

    Akhmedov, E. Kh.; Niro, Viviana

    2008-12-01

    A simple closed-form analytic expression for the probability of two-flavour neutrino oscillations in a matter with an arbitrary density profile is derived. Our formula is based on a perturbative expansion and allows an easy calculation of higher order corrections. The expansion parameter is small when the density changes relatively slowly along the neutrino path and/or neutrino energy is not very close to the Mikheyev-Smirnov-Wolfenstein (MSW) resonance energy. Our approximation is not equivalent to the adiabatic approximation and actually goes beyond it. We demonstrate the validity of our results using a few model density profiles, including the PREM density profile of the Earth. It is shown that by combining the results obtained from the expansions valid below and above the MSW resonance one can obtain a very good description of neutrino oscillations in matter in the entire energy range, including the resonance region.

  1. Three neutrino flavors: Oscillations, mixing, and the solar-neutrino problem

    International Nuclear Information System (INIS)

    Pantaleone, J.

    1991-01-01

    An analytical, quantitative description of solar-neutrino propagation is presented which includes three flavors, matter dependence, and long-wavelength effects. Using the derived expression for the electron-neutrino survival probability, it is demonstrated that mixing is possible between the two-flavor Mikheyev-Smirnov-Wolfenstein and two-flavor long-wavelength solutions to the solar-neutrino problem. However, adiabatic conversion of a neutrino mass eigenstate tends to suppress all subsequent long-wavelength effects such as ''seasonal'' variations in the solar-neutrino flux

  2. Studies of neutrino asymmetries generated by ordinary-sterile neutrino oscillations in the early Universe and implications for big bang nucleosynthesis bounds

    Energy Technology Data Exchange (ETDEWEB)

    Foot, R.; Volkas, R.R. [Research Centre for High Energy Physics, School of Physics, University of Melbourne, Parkville, 3052 (Australia)

    1997-04-01

    Ordinary-sterile neutrino oscillations can generate a significant lepton number asymmetry in the early Universe. We study this phenomenon in detail. We show that the dynamics of ordinary-sterile neutrino oscillations in the early Universe can be approximately described by a single integrodifferential equation which we derive from both the density matrix and Hamiltonian formalisms. This equation reduces to a relatively simple ordinary first-order differential equation if the system is sufficiently smooth (static limit). We study the conditions for which the static limit is an acceptable approximation. We also study the effect of the thermal distribution of neutrino momenta on the generation of lepton number. We apply these results to show that it is possible to evade (by many orders of magnitude) the big bang nucleosynthesis (BBN) bounds on the mixing parameters {delta}m{sup 2} and sin{sup 2}2{theta}{sub 0} describing ordinary-sterile neutrino oscillations. We show that the large angle or maximal vacuum oscillation solution to the solar neutrino problem does not significantly modify BBN for most of the parameter space of interest, provided that the {tau} and/or {mu} neutrinos have masses greater than about 1 eV. We also show that the large angle or maximal ordinary-sterile neutrino oscillation solution to the atmospheric neutrino anomaly does not significantly modify BBN for a range of parameters. {copyright} {ital 1997} {ital The American Physical Society}

  3. Studying neutrino oscillations using quasi-elastic events in MINOS

    Energy Technology Data Exchange (ETDEWEB)

    Kumaratunga, Sujeewa Terasita [Univ. of Minnesota, Minneapolis, MN (United States)

    2008-02-01

    MINOS (Main Injector Neutrino Oscillation Search), is a long baseline neutrino experiment designed to search for neutrino oscillations using two detectors at Fermi National Accelerator Laboratory, IL (Near Detector) and Soudan, MN (Far Detector). It will study vμ → vτ oscillations and make a measurement on the oscillation parameters, Δm$2\\atop{23}$ and sin223, via a vμ beam made at Fermilab. Charge current neutrino interactions in the MINOS detectors are of three types: quasi-elastic scattering (QEL), resonance scattering (RES) and deep inelastic scattering (DIS). Of these, quasi-elastic scattering leaves the cleanest signal with just one μ and one proton in the final state, thus rendering the reconstruction of the neutrino energy more accurate. This thesis will outline a method to separate QEL events from the others in the two detectors and perform a calculation of Δm$2\\atop{23}$ and sin223 using those events. The period under consideration was May 2005 to February 2006. The number of observed quasi-elastic events with energies below 10 GeV was 29, where the expected number was 60 ± 3. A fit to the energy distribution of these events gives Δm$2\\atop{23}$ = 2.91$+0.49\\atop{-0.53}$(stat)$+0.08\\atop{-0.09}$(sys) x 10-3 eV2 and sin223 = 0.990-0.180(stat)-0.030(sys).

  4. Supernova neutrino detection

    International Nuclear Information System (INIS)

    Selvi, M.

    2005-01-01

    Neutrinos emitted during a supernova core collapse represent a unique feature to study both stellar and neutrino properties. After discussing the details of the neutrino emission in the star and the effect of neutrino oscillations on the expected neutrino fluxes at Earth, a review of the detection techniques is presented in this paper, with particular attention to the problem of electron neutrino detection

  5. The Effect of Neutrino Oscillations on Supernova Light Element Synthesis

    International Nuclear Information System (INIS)

    Yoshida, Takashi; Kajino, Toshitaka; Yokomakura, Hidekazu; Kimura, Keiichi; Takamura, Akira; Hartmann, Dieter H.

    2006-01-01

    We investigate light element synthesis through the ν-process during supernova explosions considering neutrino oscillations and investigate the dependence of 7Li and 11B yields on neutrino oscillation parameters mass hierarchy and θ13. The adopted supernova explosion model for explosive nucleosynthesis corresponds to SN 1987A. The 7Li and 11B yields increase by about factors of 1.9 and 1.3 in the case of normal mass hierarchy and adiabatic 13-mixing resonance compared with the case without neutrino oscillations. In the case of inverted mass hierarchy or nonadiabatic 13-mixing resonance, the increase in 7Li and 11B yields is much smaller. Astronomical observations of 7Li/11B ratio in stars formed in regions strongly affected by prior generations of supernovae would constrain mass hierarchy and the range of θ13

  6. Sterile neutrino oscillations in MINOS and hadron production in pC collisions

    Energy Technology Data Exchange (ETDEWEB)

    Tinti, Gemma Maria [Univ. of Oxford (United Kingdom)

    2010-01-01

    MINOS is a long baseline neutrino oscillation experiment, starting with a muon-neutrino beam, for the precise measurement of the atmospheric neutrino oscillation parameters |Δm2| and θ23. The Near Detector measures the neutrino flux and spectra before oscillations. The beam propagates for 735 km to the Far Detector, which measures the depleted spectrum after oscillations. The depletion can be interpreted as vμ → vτ oscillations. Subdominant vμ → ve oscillations may be allowed if the mixing angle θ13 ≠ 0. The two detectors are functionally identical in order to cancel systematic errors when using the Near Detector data to constrain the Far Detector prediction. A crucial part of the analysis is the relative calibration between the two detectors, which is known at the 2% level. A calibration procedure to remove the time and temperature dependence of the detector response using through-going cosmic muons is presented here. Although the two-detector approach reduces the systematic uncertainties related to the neutrino flux, a cross check on the neutrino parent meson ratios is performed in this thesis. The cross sections of mesons produced in proton-carbon interactions from the NA49 experiment have been measured and the results have been compared to the MINOS expectations. A neutrino oscillation analysis allowing mixing to a sterile neutrino is performed, under the assumption that the additional mass splitting is Ο(1 eV2). The analysis uses the energy spectrum of the neutral current interaction products, as neutral current interactions are sensitive to sterile neutrino mixing but not to the active flavour neutrino mixing. The neutrino oscillation parameters have been found to be: |Δm2| = 2.43-0.18+0.21 x 10-3 eV2, θ23 = 40.27°-5.17+14.64, θ24 = 0.00°+5.99 and

  7. Phenomenology of neutrino oscillations at the neutrino factory

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Jian

    2011-12-19

    We consider the prospects for a neutrino factory measuring mixing angles, the CP violating phase and mass-squared differences by detecting wrong-charge muons arising from the chain {mu}{sup +} {yields} {nu}{sub e} {yields} {nu}{sub {mu}} {yields} {mu}{sup -} and the right-charge muons coming from the chain {mu}{sup +} {yields} anti {nu}{sub {mu}} {yields} anti {nu}{sub {mu}} {yields} {mu}{sup -} (similar to {mu}{sup -} chains), where {nu}{sub e} {yields} {nu}{sub {mu}} and anti {nu}{sub {mu}} {yields} anti {nu}{sub {mu}} are neutrino oscillation channels through a long baseline. First, we study physics with near detectors and consider the treatment of systematic errors including cross section errors, flux errors, and background uncertainties. We illustrate for which measurements near detectors are required, discuss how many are needed, and what the role of the flux monitoring is. We demonstrate that near detectors are mandatory for the leading atmospheric parameter measurements if the neutrino factory has only one baseline, whereas systematic errors partially cancel if the neutrino factory complex includes the magic baseline. Second, we perform the baseline and energy optimization of the neutrino factory including the latest simulation results from the magnetized iron neutrino detector (MIND). We also consider the impact of {tau} decays, generated by appearance channels {nu}{sub {mu}} {yields} {nu}{sub {tau}} and {nu}{sub e} {yields} {nu}{sub {tau}}, on the discovery reaches of the mass orderings, the leptonic CP violation, and the non-zero {theta}{sub 13}, which we find to be negligible for the considered detector. Third, we make a comparison of a high energy neutrino factory to a low energy neutrino factory and find that they are just two versions of the same experiment optimized for different regions of the parameter space. In addition, we briefly comment on whether it is useful to build the bi-magic baseline at the low energy neutrino factory. Finally, the

  8. Leptogenesis from oscillations of heavy neutrinos with large mixing angles

    Energy Technology Data Exchange (ETDEWEB)

    Drewes, Marco; Garbrecht, Björn [Physik-Department T70, Technische Universität München,James-Franck-Straße, 85748 Garching (Germany); Gueter, Dario [Physik-Department T70, Technische Universität München,James-Franck-Straße, 85748 Garching (Germany); Max-Planck-Institut für Physik (Werner-Heisenberg-Institut),Föhringer Ring 6, 80805 München (Germany); Excellence Cluster Universe, Technische Universität München,Boltzmannstraße 2, 85748 Garching (Germany); Klarić, Juraj [Physik-Department T70, Technische Universität München,James-Franck-Straße, 85748 Garching (Germany)

    2016-12-29

    The extension of the Standard Model by heavy right-handed neutrinos can simultaneously explain the observed neutrino masses via the seesaw mechanism and the baryon asymmetry of the Universe via leptogenesis. If the mass of the heavy neutrinos is below the electroweak scale, they may be found at the LHC, BELLE II, NA62, the proposed SHiP experiment or a future high-energy collider. In this mass range, the baryon asymmetry is generated via CP-violating oscillations of the heavy neutrinos during their production. We study the generation of the baryon asymmetry of the Universe in this scenario from first principles of non-equilibrium quantum field theory, including spectator processes and feedback effects. We eliminate several uncertainties from previous calculations and find that the baryon asymmetry of the Universe can be explained with larger heavy neutrino mixing angles, increasing the chance for an experimental discovery. For the limiting cases of fast and strongly overdamped oscillations of right-handed neutrinos, the generation of the baryon asymmetry can be calculated analytically up to corrections of order one.

  9. Global Analysis of Solar Neutrino Oscillations Including SNO CC Measurement

    CERN Document Server

    Bahcall, J N; Peña-Garay, C; Bahcall, John N; Peña-Garay, Carlos

    2001-01-01

    For active and sterile neutrinos, we present the globally allowed solutions for two neutrino oscillations. We include the SNO CC measurement and all other relevant solar neutrino and reactor data. Five active neutrino oscillation solutions (LMA, LOW, SMA, VAC, and Just So2) are currently allowed at 3 sigma; three sterile neutrino solutions (Just So2, SMA, and VAC) are allowed at 3 sigma. The goodness of fit is satisfactory for all eight solutions. We also investigate the robustness of the allowed solutions by carrying out global analyses with and without: 1) imposing solar model constraints on the 8B neutrino flux, 2) including the Super-Kamiokande spectral energy distribution and day-night data, 3) using an enhanced CC cross section for deuterium (due to radiative corrections), and 4) a optimistic, hypothetical reduction by a factor of three of the error of the SNO CC rate. For every analysis strategy used in this paper, the most favored solutions all involve large mixing angles: LMA, LOW, or VAC. The favore...

  10. Wave-packet treatment of reactor neutrino oscillation experiments and its implications on determining the neutrino mass hierarchy

    Energy Technology Data Exchange (ETDEWEB)

    Chan, Yat-Long; Chu, M.C.; Xu, Jianyi [The Chinese University of Hong Kong, Department of Physics, Shatin (China); Tsui, Ka Ming [University of Tokyo, RCCN, ICRR, Kashiwa, Chiba (Japan); Wong, Chan Fai [Sun Yat-Sen University, Guangzhou (China)

    2016-06-15

    We derive the neutrino flavor transition probabilities with the neutrino treated as a wave packet. The decoherence and dispersion effects from the wave-packet treatment show up as damping and phase-shifting of the plane-wave neutrino oscillation patterns. If the energy uncertainty in the initial neutrino wave packet is larger than around 0.01 of the neutrino energy, the decoherence and dispersion effects would degrade the sensitivity of reactor neutrino experiments to mass hierarchy measurement to lower than 3 σ confidence level. (orig.)

  11. Variables for probing neutrino oscillation at super- Kamiokande and ...

    Indian Academy of Sciences (India)

    and Sudbury Neutrino Observatory experiments and can sensitively signal neutrino oscillations. One class of such variables involve moments of the distributions recorded at the two facilities while another variable, specific to SNO, utilises the integrated charged and neutral current signals. The utility of these variables in the ...

  12. Asymmetric Collision of Concepts: Why Eigenstates Alone are Not Enough for Neutrino Flavor Oscillations

    OpenAIRE

    Williams, John Michael

    2000-01-01

    The symmetry of the problem of the apparent deficit in upward-going atmospheric muon neutrinos reveals two possible, nonexclusive kinds of solution: Nonlinearity in distance or nonlinearity in angle of observation. Nonlinearity in distance leads to the most popular theory for the atmospheric problem, neutrino flavor oscillations. If the observed deficit is caused by oscillations and not, say, flavor-changing or other weak-force scattering, neutrinos must be massive. But, if flavor oscillation...

  13. Expression of Interest for a very long baseline neutrino oscillation experiment (LBNO)

    CERN Document Server

    Stahl, A; Guler, A M; Kamiscioglu, M; Sever, R; Yilmazer, A U; Gunes, C; Yilmaz, D; Del Amo Sanchez, P; Duchesneau, D; Pessard, H; Marcoulaki, E; Papazoglou, I A; Berardi, V; Cafagna, F; Catanesi, M G; Magaletti, L; Mercadante, A; Quinto, M; Radicioni, E; Ereditato, A; Kreslo, I; Pistillo, C; Weber, M; Ariga, A; Ariga, T; Strauss, T; Hierholzer, M; Kawada, J; Hsu, C; Haug, S; Jipa, A; Lazanu, I; Cardini, A; Lai, A; Oldeman, R; Thomson, M; Blake, A; Prest, M; Auld, A; Elliot, J; Lumbard, J; Thompson, C; Gornushkin, Y A; Pascoli, S; Collins, R; Haworth, M; Thompson, J; Bencivenni, G; Domenici, D; Longhin, A; Blondel, A; Bravar, A; Dufour, F; Karadzhov, Y; Korzenev, A; Noah, E; Ravonel, M; Rayner, M; Asfandiyarov, R; Haesler, A; Martin, C; Scantamburlo, E; Cadoux, F; Bayes, R; Soler, F J P; Aalto-Setälä, L; Enqvist, K; Huitu, K; Rummukainen, K; Nuijten, G; Eskola, K J; Kainulainen, K; Kalliokoski, T; Kumpulainen, J; Loo, K; Maalampi, J; Manninen, M; Moore, I; Suhonen, J; Trzaska, W H; Tuominen, K; Virtanen, A; Bertram, I; Finch, A; Grant, N; Kormos, L L; Ratoff, P; Christodoulou, G; Coleman, J; Touramanis, C; Mavrokoridis, K; Murdoch, M; McCauley, N; Payne, D; Jonsson, P; Kaboth, A; Long, K; Malek, M; Scott, M; Uchida, Y; Wascko, M O; Di Lodovico, F; Wilson, J R; Still, B; Sacco, R; Terri, R; Campanelli, M; Nichol, R; Thomas, J; Izmaylov, A; Khabibullin, M; Khotjantsev, A; Kudenko, Y; Matveev, V; Mineev, O; Yershov, N; Palladino, V; Evans, J; Söldner-Rembold, S; Yang, U K; Bonesini, M; Pihlajaniemi, T; Weckström, M; Mursula, K; Enqvist, T; Kuusiniemi, P; Räihä, T; Sarkamo, J; Slupecki, M; Hissa, J; Kokko, E; Aittola, M; Barr, G; Haigh, M D; de Jong, J; O'Keeffe, H; Vacheret, A; Weber, A; Galvanin, G; Temussi, M; Caretta, O; Davenne, T; Densham, C; Ilic, J; Loveridge, P; Odell, J; Wark, D; Robert, A; Andrieu, B; Popov, B; Giganti, C; Levy, J -M; Dumarchez, J; Buizza-Avanzini, M; Cabrera, A; Dawson, J; Franco, D; Kryn, D; Obolensky, M; Patzak, T; Tonazzo, A; Vanucci, F; Orestano, D; Di Micco, B; Tortora, L; Bésida, O; Delbart, A; Emery, S; Galymov, V; Mazzucato, E; Vasseur, G; Zito, M; Kudryavtsev, V A; Thompson, L F; Tsenov, R; Kolev, D; Rusinov, I; Bogomilov, M; Vankova, G; Matev, R; Vorobyev, A; Novikov, Yu; Kosyanenko, S; Suvorov, V; Gavrilov, G; Baussan, E; Dracos, M; Jollet, C; Meregaglia, A; Vallazza, E; Agarwalla, S K; Li, T; Autiero, D; Chaussard, L; Déclais, Y; Marteau, J; Pennacchio, E; Rondio, E; Lagoda, J; Zalipska, J; Przewlocki, P; Grzelak, K; Barker, G J; Boyd, S; Harrison, P F; Litchfield, R P; Ramachers, Y; Badertscher, A; Curioni, A; Degunda, U; Epprecht, L; Gendotti, A; Knecht, L; Di Luise, S; Horikawa, S; Lussi, D; Murphy, S; Natterer, G; Petrolo, F; Periale, L; Rubbia, A; Sergiampietri, F; Viant, T

    2012-01-01

    This Expression of Interest (EoI) describes the motivation for and the feasibility studies of a long baseline neutrino oscillation experiment (LBNO) with a new conventional neutrino beamline facility (CN2PY). The beam will be aimed at a next generation deep-underground neutrino observatory comprising a double phase liquid argon (LAr) detector and a magnetized iron calorimeter, located at the Pyh\\"asalmi (Finland) mine at a distance of 2300~km. The double phase LAr Large Electron Multiplier Time Projection Chamber (LAr LEM-TPC) is known to provide excellent tracking and calorimetry performance that can outperform other techniques. An initial 20~kton LAr fiducial volume, as considered here, comparable to the fiducial mass of SuperKamiokande and NOvA, offers a new insight and an increase in sensitivity reach for many physics channels. A magnetized iron calorimeter with muon momentum and charge determination collects an independent neutrino sample, and serves as a tail catcher for CERN beam eve...

  14. Short distance neutrino oscillations with Borexino

    Directory of Open Access Journals (Sweden)

    Caminata A.

    2016-01-01

    Full Text Available The Borexino detector has convincingly shown its outstanding performances in the low energy, sub-MeV regime through its unprecedented accomplishments in the solar and geo-neutrinos detection. These performances make it the ideal tool to accomplish a state-of-the-art experiment able to test unambiguously the long-standing issue of the existence of a sterile neutrino, as suggested by the several anomalous results accumulated over the past two decades, i.e. the outputs of the LSND and Miniboone experiments, the results of the source calibration of the two Gallium solar neutrino experiments, and the recently hinted reactor anomaly. The SOX project will exploit two sources, based on Chromium and Cerium, respectively, which deployed under the experiment, in a location foreseen on purpose at the time of the construction of the detector, will emit two intense beams of neutrinos (Cr and anti-neutrinos (Ce. Interacting in the active volume of the liquid scintillator, each beam would create an unmistakable spatial wave pattern in case of oscillation of the νe (or ν̅e into the sterile state: such a pattern would be the smoking gun proving the existence of the new sterile member of the neutrino family. Otherwise, its absence will allow setting a very stringent limit on its existence.

  15. Violation of the Leggett-Garg Inequality in neutrino oscillations

    Science.gov (United States)

    Weiss, T. E.; Formaggio, J. A.; Kaiser, D. I.; Murskyj, M. M.

    2017-09-01

    The Leggett-Garg inequality, an analogue of Bell’s inequality involving correlations of measurements on a system at different times, stands as one of the hallmark tests of quantum mechanics against classical predictions. The phenomenon of neutrino oscillations should adhere to quantum-mechanical predictions and provide an observable violation of the Leggett-Garg inequality. We demonstrate how oscillation phenomena can be used to test for violations of the classical bound by performing measurements on an ensemble of neutrinos at distinct energies, as opposed to a single neutrino at distinct times. A study of the MINOS experiment’s data shows a greater than 6σ violation over a distance of 735 km, representing the longest distance over which either the Leggett-Garg inequality or Bell’s inequality has been tested.

  16. Three-flavoured neutrino oscillations and the Leggett-Garg inequality

    Energy Technology Data Exchange (ETDEWEB)

    Gangopadhyay, Debashis; Roy, Animesh Sinha [Ramakrishna Mission Vivekananda University, Department of Physics, Howrah, West Bengal (India)

    2017-04-15

    Three-flavoured neutrino oscillations are investigated in the light of the Leggett-Garg inequality (LGI). The results obtained are: (a) The maximum violation of the LGI is 2.17036 for neutrino path length L{sub 1} = 140.15 km and ΔL = 1255.7 km. (b) The presence of the mixing angle θ{sub 13} enhances the maximum violation of LGI by 4.6%. (c) The currently known mass hierarchy parameter α = 0.0305 increases the maximum violation of LGI by 3.7%. (d) The presence of a CP-violating phase parameter enhances the maximum violation of LGI by 0.24%, thus providing an alternative indicator of CP violation in three-flavoured neutrino oscillations. The outline of an experimental proposal is suggested whereby the findings of this investigation may be verified. (orig.)

  17. High intensity neutrino oscillation facilities in Europe

    CERN Document Server

    Edgecock, T.R.; Davenne, T.; Densham, C.; Fitton, M.; Kelliher, D.; Loveridge, P.; Machida, S.; Prior, C.; Rogers, C.; Rooney, M.; Thomason, J.; Wilcox, D.; Wildner, E.; Efthymiopoulos, I.; Garoby, R.; Gilardoni, S.; Hansen, C.; Benedetto, E.; Jensen, E.; Kosmicki, A.; Martini, M.; Osborne, J.; Prior, G.; Stora, T.; Melo-Mendonca, T.; Vlachoudis, V.; Waaijer, C.; Cupial, P.; Chancé, A.; Longhin, A.; Payet, J.; Zito, M.; Baussan, E.; Bobeth, C.; Bouquerel, E.; Dracos, M.; Gaudiot, G.; Lepers, B.; Osswald, F.; Poussot, P.; Vassilopoulos, N.; Wurtz, J.; Zeter, V.; Bielski, J.; Kozien, M.; Lacny, L.; Skoczen, B.; Szybinski, B.; Ustrzycka, A.; Wroblewski, A.; Marie-Jeanne, M.; Balint, P.; Fourel, C.; Giraud, J.; Jacob, J.; Lamy, T.; Latrasse, L.; Sortais, P.; Thuillier, T.; Mitrofanov, S.; Loiselet, M.; Keutgen, Th.; Delbar, Th.; Debray, F.; Trophine, C.; Veys, S.; Daversin, C.; Zorin, V.; Izotov, I.; Skalyga, V.; Burt, G.; Dexter, A.C.; Kravchuk, V.L.; Marchi, T.; Cinausero, M.; Gramegna, F.; De Angelis, G.; Prete, G.; Collazuol, G.; Laveder, M.; Mazzocco, M.; Mezzetto, M.; Signorini, C.; Vardaci, E.; Di Nitto, A.; Brondi, A.; La Rana, G.; Migliozzi, P.; Moro, R.; Palladino, V.; Gelli, N.; Berkovits, D.; Hass, M.; Hirsh, T.Y.; Schaumann, M.; Stahl, A.; Wehner, J.; Bross, A.; Kopp, J.; Neuffer, D.; Wands, R.; Bayes, R.; Laing, A.; Soler, P.; Agarwalla, S.K.; Cervera Villanueva, A.; Donini, A.; Ghosh, T.; Gómez Cadenas, J.J.; Hernández, P.; Martín-Albo, J.; Mena, O.; Burguet-Castell, J.; Agostino, L.; Buizza-Avanzini, M.; Marafini, M.; Patzak, T.; Tonazzo, A.; Duchesneau, D.; Mosca, L.; Bogomilov, M.; Karadzhov, Y.; Matev, R.; Tsenov, R.; Akhmedov, E.; Blennow, M.; Lindner, M.; Schwetz, T.; Fernández Martinez, E.; Maltoni, M.; Menéndez, J.; Giunti, C.; González García, M. C.; Salvado, J.; Coloma, P.; Huber, P.; Li, T.; López-Pavón, J.; Orme, C.; Pascoli, S.; Meloni, D.; Tang, J.; Winter, W.; Ohlsson, T.; Zhang, H.; Scotto-Lavina, L.; Terranova, F.; Bonesini, M.; Tortora, L.; Alekou, A.; Aslaninejad, M.; Bontoiu, C.; Kurup, A.; Jenner, L.J.; Long, K.; Pasternak, J.; Pozimski, J.; Back, J.J.; Harrison, P.; Beard, K.; Bogacz, A.; Berg, J.S.; Stratakis, D.; Witte, H.; Snopok, P.; Bliss, N.; Cordwell, M.; Moss, A.; Pattalwar, S.; Apollonio, M.

    2013-02-20

    The EUROnu project has studied three possible options for future, high intensity neutrino oscillation facilities in Europe. The first is a Super Beam, in which the neutrinos come from the decay of pions created by bombarding targets with a 4 MW proton beam from the CERN High Power Superconducting Proton Linac. The far detector for this facility is the 500 kt MEMPHYS water Cherenkov, located in the Fr\\'ejus tunnel. The second facility is the Neutrino Factory, in which the neutrinos come from the decay of {\\mu}+ and {\\mu}- beams in a storage ring. The far detector in this case is a 100 kt Magnetised Iron Neutrino Detector at a baseline of 2000 km. The third option is a Beta Beam, in which the neutrinos come from the decay of beta emitting isotopes, in particular 6He and 18Ne, also stored in a ring. The far detector is also the MEMPHYS detector in the Fr\\'ejus tunnel. EUROnu has undertaken conceptual designs of these facilities and studied the performance of the detectors. Based on this, it has determined the ph...

  18. Impact of Neutrino Oscillation Measurements on Theory

    International Nuclear Information System (INIS)

    Murayama, Hitoshi

    2003-01-01

    Neutrino oscillation data had been a big surprise to theorists, and indeed they have ongoing impact on theory. I review what the impact has been, and what measurements will have critical impact on theory in the future.

  19. Neutrino oscillations on and off the beam: studies of the OPERA acquisition system performance

    International Nuclear Information System (INIS)

    Brugiere, T.

    2011-01-01

    OPERA (Oscillation Project with Emulsion-tracking Apparatus) is a neutrino beam experiment located in hall C of the Gran Sasso underground laboratory (LNGS), in Italia, under a equivalent of 3.8 km water (corresponding to a cut at 1.5 TeV for the muons). The first purpose of OPERA is the direct observation of the ν μ → ν τ oscillation in the atmospheric sector observing a ν τ appearance 730 km away from the target in a quasi pure ν μ beam (CNGS). OPERA is an hybrid detector with an instrumented target part (about 125000 bricks made with emulsion and lead sheets) and a spectrometer. Collecting data started in 2006 and 55000 events have been recorded. The first ν τ candidate have been observed this year. The work done during this thesis is oriented around three main topics: Define the trigger rules of the target tracker acquisition system for beam neutrino events, synchronise target tracker and RPC elements, implement the results inside the simulation and the study of the feasibility of an atmospheric neutrino analysis using o-beam data. The new trigger rules succeeds to reach the values of OPERA proposal, i.e. a trigger efficiency greater than 99%. This improvement have been done thanks to coincidence time windows with the CNGS beam during which lower cut are applied, allowing low multiplicity events to be kept. A deep study of electronic detectors intercalibration makes possible the target tracker and RPC data synchronisation. The analysis results are now included in the official simulation. This calibration work have been then used for a study of 'off-beam' atmospheric neutrino oscillation thanks to the selection of up-going particles. The analysis shown in the thesis has improved the OPERA detector understanding and demonstrates the feasibility of an observation of phenomena independent from the Cgs beam. Analysis on atmospherics neutrino detection and muons flux characterisation (seasonal variations for example) are now possible thanks to the

  20. Search of neutrino oscillations by ντ appearance with τ decay in the muonic channel in OPERA experiment

    International Nuclear Information System (INIS)

    Tran, N.T.

    2010-10-01

    Neutrino oscillations, based on a change of flavor state of a neutrino during its propagation, can explain the deficits observed on solar and atmospheric neutrinos and provide some interesting indications for physics beyond the Standard Model by studying the mixing angles and the hierarchy of neutrino mass. The OPERA experiment is the first experiment designed to observe the appearance of a ν τ by the oscillation of the ν μ to ν τ in the CNGS beam from CERN to Gran Sasso. OPERA is a hybrid detector combining both the technique of an on time electronic detection and the technique of emulsion cloud chamber (ECC). The ECC detector is a passive detector (target) of 150.000 bricks, each one consisting of sheets of lead, used as target, alternating with nuclear photographic emulsions whose accuracy of track reconstruction is about one micron. The detector also includes two spectrometers with magnetized iron plates 5 cm thick alternating with RPC (resistive plate chamber) associated with six sets of drift tubes for the measurement of the charge and momentum of the muon. It includes also a Veto plane used for rejection of particles coming outside the target. This detector simultaneously allows a high spatial resolution and a large target mass which are two very conditions necessary for collecting charged current neutrino interactions from oscillated ν τ and observing the decay topology of τ. This thesis presents a study on tau decay in the muonic channel. It has contributed to 1) the development of an algorithm for the selection of the neutrino interactions in the target, 2) the studies on the muon identification in electronic detectors and the connection of its trace with those reconstructed in the emulsions, which represent a fundamental point both for the tau signal identification as the rejection of charmed background, 3) the development of a neural network to discriminate the signal from the charmed background regardless of the muon identification in

  1. Neutrino oscillations a practical guide to basics and applications

    CERN Document Server

    Suekane, Fumihiko

    2015-01-01

    Neutrino oscillation (N.O.) is the only firm evidence of the physics beyond the Standard Model of particle physics and is one of the hottest topics in elementary particle physics today. This book focuses on the N.O., from its history to the future prospects, from the basic theories to the experiments.     Various phenomena of N.O. are described intuitively with thorough explanations of the fundamental physics behind well-known formulations. For example, while many textbooks start with a discussion of the mixing matrix, this book stresses that N.O. is caused by the transition amplitudes between different neutrino flavors, and that the purpose of N.O. experiments is to measure transition amplitudes and think of its origin. The current understanding of neutrino oscillation is also summarized using the most up-to-date measurements, including the recently measured neutrino mixing angle θ13, and the future prospects of N.O. studies are described as well. The level of this book makes it a bridge between introdu...

  2. Prospects for experiments on neutrino masses and mixing via neutrino oscillations at future accelerators

    International Nuclear Information System (INIS)

    Lanou, R.E. Jr.

    1982-01-01

    A study is made of the requirements necessary for improvement in our knowledge of limits in mass and mixing parameters for neutrinos via oscillation phenomena at accelerators. It is concluded that increased neutrino event rate (flux x energy) at modest energy machines (e.g., AGS and LAMPF) is the single most important requirement. This will permit smaller E/L ratios and refinement of systematics

  3. Beam and experiments summary [neutrino studies

    CERN Document Server

    Blondel, A; Campanelli, M; Cervera-Villanueva, Anselmo; Cline, David B; Collot, J; De Jong, M; Donini, Andrea; Dydak, Friedrich; Edgecock, R; Gavela-Legazpi, Maria Belen; Gómez-Cadenas, J J; González-Garciá, M Concepción; Gruber, P; Harris, D A; Hernández, Pilar; Kuno, Y; Litchfield, P J; McFarland, K; Mena, O; Migliozzi, P; Palladino, Vittorio; Panman, J; Papadopoulos, I M; Para, A; Peña-Garay, C; Pérez, P; Rigolin, Stefano; Romanino, Andrea; Rubbia, André; Strolin, P; Wojcicki, S G

    2000-01-01

    The discovery of neutrino oscillations marks a major milestone in the history of neutrino physics, and opens a new window to the still mysterious origin of masses and flavour mixing. Many current and forthcoming experiments will. Answer open questions; however, a major step forward, up to and possibly including CP violation in the neutrino-mixing matrix, requires the neutrino beams from a neutrino factory. The neutrino factory is a new concept for producing neutrino beams of unprecedented quality in terms of intensity, flavour composition, and precision of the beam parameters. Most importantly, the neutrino factory is the only known way to generate a high- intensity beam of electron neutrinos of high energy. The neutrino beam from a neutrino factory, in particular the electron-neutrino beam, enables the exploration of otherwise inaccessible domains in neutrino oscillation physics by exploiting baselines of planetary dimensions. Suitable detectors pose formidable challenges but seem within reach with only mode...

  4. Updated Global Analysis of Neutrino Oscillations in the Presence of eV-Scale Sterile Neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Dentler, Mona [U. Mainz, PRISMA; Hernández-Cabezudo, Alvaro [KIT, Karlsruhe, IKP; Kopp, Joachim [CERN; Machado, Pedro [Fermilab; Maltoni, Michele [Madrid, IFT; Martinez-Soler, Ivan [Madrid, IFT; Schwetz, Thomas [KIT, Karlsruhe, IKP

    2018-03-28

    We discuss the possibility to explain the anomalies in short-baseline neutrino oscillation experiments in terms of sterile neutrinos. We work in a 3+1 framework and pay special attention to recent new data from reactor experiments, IceCube and MINOS+. We find that results from the DANSS and NEOS reactor experiments support the sterile neutrino explanation of the reactor anomaly, based on an analysis that relies solely on the relative comparison of measured reactor spectra. Global data from the $\

  5. Simple and compact expressions for neutrino oscillation probabilities in matter

    International Nuclear Information System (INIS)

    Minakata, Hisakazu; Parke, Stephen J.

    2016-01-01

    We reformulate perturbation theory for neutrino oscillations in matter with an expansion parameter related to the ratio of the solar to the atmospheric Δm"2 scales. Unlike previous works, we use a renormalized basis in which certain first-order effects are taken into account in the zeroth-order Hamiltonian. We show that the new framework has an exceptional feature that leads to the neutrino oscillation probability in matter with the same structure as in vacuum to first order in the expansion parameter. It facilitates immediate physical interpretation of the formulas, and makes the expressions for the neutrino oscillation probabilities extremely simple and compact. We find, for example, that the ν_e disappearance probability at this order is of a simple two-flavor form with an appropriately identified mixing angle and Δm"2. More generally, all the oscillation probabilities can be written in the universal form with the channel-discrimination coefficient of 0, ±1 or simple functions of θ_2_3. Despite their simple forms they include all order effects of θ_1_3 and all order effects of the matter potential, to first order in our expansion parameter.

  6. Towards the resolution of the solar neutrino problem

    Energy Technology Data Exchange (ETDEWEB)

    Friedland, Alexander [Univ. of California, Berkeley, CA (United States)

    2000-08-01

    A number of experiments have accumulated over the years a large amount of solar neutrino data. The data indicate that the observed solar neutrino flux is significantly smaller than expected and, furthermore, that the electron neutrino survival probability is energy dependent. This ''solar neutrino problem'' is best solved by assuming that the electron neutrino oscillates into another neutrino species. Even though one can classify the solar neutrino deficit as strong evidence for neutrino oscillations, it is not yet considered a definitive proof. Traditional objections are that the evidence for solar neutrino oscillations relies on a combination of hard, different experiments, and that the Standard Solar Model (SSM) might not be accurate enough to precisely predict the fluxes of different solar neutrino components. Even though it seems unlikely that modifications to the SSM alone can explain the current solar neutrino data, one still cannot completely discount the possibility that a combination of unknown systematic errors in some of the experiments and certain modifications to the SSM could conspire to yield the observed data. To conclusively demonstrate that there is indeed new physics in solar neutrinos, new experiments are aiming at detecting ''smoking gun'' signatures of neutrino oscillations, such as an anomalous seasonal variation in the observed neutrino flux or a day-night variation due to the regeneration of electron neutrinos in the Earth. In this dissertation we study the sensitivity reach of two upcoming neutrino experiments, Borexino and KamLAND, to both of these effects. Results of neutrino oscillation experiments for the case of two-flavor oscillations have always been presented on the (sin2 2θ, Δm2) parameter space. We point out, however, that this parameterization misses the half of the parameter space π/4 < θ < π/2, which is physically inequivalent to the region 0 < θ < π/4 in

  7. Exotic muon decays and searches for neutrino oscillations

    International Nuclear Information System (INIS)

    Herczeg, P.

    1997-06-01

    Experiments that search for anti ν e 's from μ + -decay are sensitive not only to oscillations of neutrinos into anti ν e , but also to μ + → e + anti ν e n x decays, where n x is a neutrino or an antineutrino. The author considers such muon decays and the possible size of their branching ratios in left-right symmetric models and in the minimal supersymmetric standard model with R-parity violation

  8. A proposal for a precision test of the standard model by neutrino-electron scattering (Large /hacek C/erenkov Detector Project)

    International Nuclear Information System (INIS)

    Allen, R.C.; Lu, X-Q.; Gollwitzer, K.

    1988-04-01

    A precision measurement of neutrino-electron elastic scattering from a beam stop neutrino source at LAMPF is proposed. The total error in sin 2 θ/sub W/ is estimated to be +-0.89/percent/. The experiment also will be sensitive to neutrino oscillations and supernova-neutrino bursts, and should set improved limits on the neutrino-charge radius and magnetic-dipole moment. The detector consists of a 2.5-million-gallon tank of water with approximately 14,000 photomultiplier tubes lining the surfaces of the tank. Neutrino-electron scattering events will be observed from the /hacek C/erenkov radiation emitted by the electrons in the water. 19 refs

  9. A proposal for a precision test of the standard model by neutrino-electron scattering (Large /hacek C/erenkov Detector Project)

    Energy Technology Data Exchange (ETDEWEB)

    Allen, R.C.; Lu, X-Q.; Gollwitzer, K.; Igo, G.J.; Gulmez, E.; Whitten, C.; VanDalen, G.; Layter, J.; Fung, Sun Yui; Shen, B.C.

    1988-04-01

    A precision measurement of neutrino-electron elastic scattering from a beam stop neutrino source at LAMPF is proposed. The total error in sin/sup 2/theta/sub W/ is estimated to be +-0.89/percent/. The experiment also will be sensitive to neutrino oscillations and supernova-neutrino bursts, and should set improved limits on the neutrino-charge radius and magnetic-dipole moment. The detector consists of a 2.5-million-gallon tank of water with approximately 14,000 photomultiplier tubes lining the surfaces of the tank. Neutrino-electron scattering events will be observed from the /hacek C/erenkov radiation emitted by the electrons in the water. 19 refs.

  10. Overview of the present status and challenges of neutrino oscillation physics

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-11-20

    This is an overview of the current status of neutrino oscillation physics, including atmospheric, solar, reactor and accelerator neutrino experiments. After summarizing our present understanding of all data, I discuss the open questions and how they might be addressed in the future. I also discuss how neutrinos can be used to learn about new physics and astrophysics.

  11. Polarized electron-muon neutrino scattering to electron and neutrino in noncommutative space

    Directory of Open Access Journals (Sweden)

    MM Ettefaghi

    2011-06-01

    Full Text Available For neutrino scattering from polarized electron, the weak interaction term in the cross section is significantly suppressed by the polarized term. The magnetic moment term does not receive any correction from the electron polarization. Hence, the study of the magnetic moment of neutrinos through scattering from the polarized electron leads to a stronger bound on the neutrino magnetic moment compared with the unpolarized case. On the other hand, neutrinos which are electrically neutral can couple directly with photons in Noncommutative (NC QED. In this paper, we calculate the NC QED corrections on this scattering are calculated. The phase difference between the NC term and the polarized weak interaction term is π/2. Therefore, the NC term does not destroy the above suppression.

  12. Zooming in on neutrino oscillations with DUNE

    Science.gov (United States)

    Srivastava, Rahul; Ternes, Christoph A.; Tórtola, Mariam; Valle, José W. F.

    2018-05-01

    We examine the capabilities of the DUNE experiment as a probe of the neutrino mixing paradigm. Taking the current status of neutrino oscillations and the design specifications of DUNE, we determine the experiment's potential to probe the structure of neutrino mixing and C P violation. We focus on the poorly determined parameters θ23 and δC P and consider both two and seven years of run. We take various benchmarks as our true values, such as the current preferred values of θ23 and δC P, as well as several theory-motivated choices. We determine quantitatively DUNE's potential to perform a precision measurement of θ23, as well as to test the C P violation hypothesis in a model-independent way. We find that, after running for seven years, DUNE will make a substantial step in the precise determination of these parameters, bringing to quantitative test the predictions of various theories of neutrino mixing.

  13. Preliminary Measurement of Neutrino Oscillation Parameters By NuMI/MINOS and Calibration Studies for Improving this Measurement

    International Nuclear Information System (INIS)

    Symes, Philip Andrew; Sussex U.

    2005-01-01

    This thesis explains the origins of neutrinos and their interactions, and the phenomenon of neutrino oscillations. Experiments for measuring neutrino oscillations are mentioned and the experiment investigated in this thesis, the ''Main Injector Neutrino Oscillation Search'', and its neutrino beam, the Fermi National Accelerator Laboratory's ''Neutrinos At The Main Injector'', are described. MINOS is a long baseline (735 km) neutrino oscillation experiment with a near and a far detector, intended to make precision measurements of the atmospheric sector neutrino oscillation parameters. A measurement is made of the ''atmospheric'' neutrino oscillation parameters, Δm 23 2 and sin 2 (2θ 23 ), using neutrinos from the NuMI beam. The results of this analysis are compared to measurements at MINOS using neutrinos from the atmosphere and with other experiments. A more detailed method of beam neutrino analysis is discussed, and the extra calibrations needed to perform that analysis properly are described, with special attention paid to two aspects of the calibration, which comprise the bulk of work for this thesis. The light injection calibration system uses LEDs to illuminate the detector readout and provides a normalization of the stability of the detector over time. The hardware and different modi operandi of the system are described. There is a description of installation and commissioning of the system at one of the MINOS detectors. The response normalization of each detector with cosmic ray muons is described. Special attention is paid to the explanation of necessary corrections that must be made to the muon sample in order for the sample to be used to calibrate each detector to the specified accuracy. The performance of the calibration is shown

  14. Shifts of neutrino oscillation parameters in reactor antineutrino experiments with non-standard interactions

    Directory of Open Access Journals (Sweden)

    Yu-Feng Li

    2014-11-01

    Full Text Available We discuss reactor antineutrino oscillations with non-standard interactions (NSIs at the neutrino production and detection processes. The neutrino oscillation probability is calculated with a parametrization of the NSI parameters by splitting them into the averages and differences of the production and detection processes respectively. The average parts induce constant shifts of the neutrino mixing angles from their true values, and the difference parts can generate the energy (and baseline dependent corrections to the initial mass-squared differences. We stress that only the shifts of mass-squared differences are measurable in reactor antineutrino experiments. Taking Jiangmen Underground Neutrino Observatory (JUNO as an example, we analyze how NSIs influence the standard neutrino measurements and to what extent we can constrain the NSI parameters.

  15. Neutrino oscillations in non-inertial frames and the violation of the equivalence principle neutrino mixing induced by the equivalence principle violation

    International Nuclear Information System (INIS)

    Lambiase, G.

    2001-01-01

    Neutrino oscillations are analyzed in an accelerating and rotating reference frame, assuming that the gravitational coupling of neutrinos is flavor dependent, which implies a violation of the equivalence principle. Unlike the usual studies in which a constant gravitational field is considered, such frames could represent a more suitable framework for testing if a breakdown of the equivalence principle occurs, due to the possibility to modulate the (simulated) gravitational field. The violation of the equivalence principle implies, for the case of a maximal gravitational mixing angle, the presence of an off-diagonal term in the mass matrix. The consequences on the evolution of flavor (mass) eigenstates of such a term are analyzed for solar (oscillations in the vacuum) and atmospheric neutrinos. We calculate the flavor oscillation probability in the non-inertial frame, which does depend on its angular velocity and linear acceleration, as well as on the energy of neutrinos, the mass-squared difference between two mass eigenstates, and on the measure of the degree of violation of the equivalence principle (Δγ). In particular, we find that the energy dependence disappears for vanishing mass-squared difference, unlike the result obtained by Gasperini, Halprin, Leung, and other physical mechanisms proposed as a viable explanation of neutrino oscillations. Estimations on the upper values of Δγ are inferred for a rotating observer (with vanishing linear acceleration) comoving with the earth, hence ω∝7.10 -5 rad/sec, and all other alternative mechanisms generating the oscillation phenomena have been neglected. In this case we find that the constraints on Δγ are given by Δγ≤10 2 for solar neutrinos and Δγ≤10 6 for atmospheric neutrinos. (orig.)

  16. Opportunities of Gallium Sage experiment with artificial neutrino sources for investigation of neutrino to sterile states

    International Nuclear Information System (INIS)

    Gavrin, V.N.; Gorbachiev, V.V.; Veretenkin, E.P.

    2011-01-01

    The unexpectedly low capture rate of neutrino in Ga source experiments in SAGE and GALLEX can be explained assuming electron neutrino transitions to sterile states with a mass-squared difference ∼ 1eV 2 . To test this oscillation hypothesis, we propose to place a very intense 51 Cr source at the center of a 50 tonne target of gallium metal that is divided into two zones and to measure the neutrino capture rate in each zone. The Experiment has the potential to test neutrino oscillation transitions with mass-squared difference Δm 2 > 0.5 eV 2 . An optimized SAGE setup and 3 MCi source of 51 Cr would provide a sensitivity to electron neutrino disappearance of a few percent.

  17. νΛMDM: A model for sterile neutrino and dark matter reconciles cosmological and neutrino oscillation data after BICEP2

    International Nuclear Information System (INIS)

    Ko, P.; Tang, Yong

    2014-01-01

    We propose an ultraviolet complete theory for cold dark matter (CDM) and sterile neutrinos that can accommodate both cosmological data and neutrino oscillation experiments within 1σ level. We assume a new U(1) X dark gauge symmetry which is broken at ∼O(MeV) scale resulting light dark photon. Such a light mediator for DM's self-scattering and scattering-off sterile neutrinos can resolve three controversies for cold DM on small cosmological scales: cusp vs. core, too-big-to-fail and missing satellites. We can also accommodate ∼O(1) eV scale sterile neutrinos as the hot dark matter (HDM) and can fit some neutrino anomalies from neutrino oscillation experiments within 1σ. Finally, the right amount of HDM can make a sizable contribution to dark radiation, and also helps to reconcile the tension between the data on the tensor-to-scalar ratio reported by Planck and BICEP2 Collaborations

  18. Preliminary Measurement of Neutrino Oscillation Parameters By NuMI/MINOS and Calibration Studies for Improving this Measurement

    Energy Technology Data Exchange (ETDEWEB)

    Symes, Philip Andrew [Univ. of Sussex, Brighton (United Kingdom)

    2005-11-01

    This thesis explains the origins of neutrinos and their interactions, and the phenomenon of neutrino oscillations. Experiments for measuring neutrino oscillations are mentioned and the experiment investigated in this thesis, the ''Main Injector Neutrino Oscillation Search'', and its neutrino beam, the Fermi National Accelerator Laboratory's ''Neutrinos At The Main Injector'', are described. MINOS is a long baseline (735 km) neutrino oscillation experiment with a near and a far detector, intended to make precision measurements of the atmospheric sector neutrino oscillation parameters. A measurement is made of the ''atmospheric'' neutrino oscillation parameters, Δm$2\\atop{23}$ and sin2(2θ23), using neutrinos from the NuMI beam. The results of this analysis are compared to measurements at MINOS using neutrinos from the atmosphere and with other experiments. A more detailed method of beam neutrino analysis is discussed, and the extra calibrations needed to perform that analysis properly are described, with special attention paid to two aspects of the calibration, which comprise the bulk of work for this thesis. The light injection calibration system uses LEDs to illuminate the detector readout and provides a normalization of the stability of the detector over time. The hardware and different modi operandi of the system are described. There is a description of installation and commissioning of the system at one of the MINOS detectors. The response normalization of each detector with cosmic ray muons is described. Special attention is paid to the explanation of necessary corrections that must be made to the muon sample in order for the sample to be used to calibrate each detector to the specified accuracy. The performance of the calibration is shown.

  19. On entanglement in neutrino mixing and oscillations

    International Nuclear Information System (INIS)

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

    2010-01-01

    We report on recent results about entanglement in the context of particle mixing and oscillations. We study in detail single-particle entanglement arising in two-flavor neutrino mixing. The analysis is performed first in the context of Quantum Mechanics, and then for the case of Quantum Field Theory.

  20. On entanglement in neutrino mixing and oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Blasone, Massimo; Dell' Anno, Fabio; De Siena, Silvio; Illuminati, Fabrizio, E-mail: blasone@sa.infn.i [Dipartimento di Matematica e Informatica, Universita degli Studi di Salerno, Via Ponte don Melillo, I-84084 Fisciano (Italy)

    2010-06-01

    We report on recent results about entanglement in the context of particle mixing and oscillations. We study in detail single-particle entanglement arising in two-flavor neutrino mixing. The analysis is performed first in the context of Quantum Mechanics, and then for the case of Quantum Field Theory.

  1. Searching for oscillations of atmospheric and accelerator neutrinos with GeNIUS

    International Nuclear Information System (INIS)

    Michael, Douglas G.

    1994-01-01

    A very large (17KT) fine-grained sampling calorimeter is discussed for use in studying contained events induced by atmospheric or accelerator neutrinos for the purpose of searching for neutrino oscillations. The ratio of neutral current to charged current events can be used to rule out a large region of the currently allowed parameter space with accelerator and atmospheric neutrinos providing complimentary measurements. ((orig.))

  2. Faraday effect and solar neutrino problem

    International Nuclear Information System (INIS)

    Nawaz, S.

    2001-01-01

    We have studied the Faraday effect and solar neutrino problem. Our main emphasis was on the Faraday rotation of neutrino de Broglie wave of electron-neutrino producing in the nuclear reactions in the sun and converting into any other flavor of neutrino while passing through matter and/or magnetic field of the sun. We have shown that specific Faraday angle can minimize the number of free parameters occurring in the neutrino oscillation. We have also shown that the resonant Faraday angle corresponding to the resonance of MSW effect can be obtained the knowledge of the oscillation parameter delta m/sup 2/ and the neutrino energy. Using neutrino-Faraday angle approach, we have shown that the matter enhanced neutrino oscillations is dominating over the resonant spin flavor precession (RSFP) even in the favorable region of the spin flavor procession. Using the latest solar neutrino data, we have shown that Faraday angle is almost 10/sup -3/ times smaller. This can be interpreted as the interaction of magnetic moment of neutrino with the solar magnetic field is negligibly small as compare to the effect of matter field on the neutrino oscillation. (author)

  3. Mikheyev-Smirnov-Wolfenstein enhancement of oscillations as a possible solution to the solar-neutrino problem

    International Nuclear Information System (INIS)

    Rosen, S.P.; Gelb, J.M.

    1986-01-01

    Mikheyev and Smirnov have observed that neutrino oscillations in the Sun can be greatly enhanced through the mechanism of Wolfenstein matter oscillations. We develop a qualitative understanding of this phenomenon in the small-mixing-angle limit and carry out extensive calculations in order to apply it to the solar-neutrino problem. Our simple theoretical model agrees remarkably well with the calculations. After determining those values of Δm 2 and sin 2 2theta in the small-mixing-angle limit for which the 8 B plus 7 Be neutrino capture rate in /sup 37/Cl is suppressed by a factor 2--4, we predict the corresponding capture rate for pp plus 7 Be neutrinos in /sup 71/Ga. The gallium capture rate can range from no reduction to a factor of 10 reduction. We also determine the modified spectrum of 8 B neutrinos arriving at Earth and discuss the importance of this spectrum as a means of choosing between oscillations and the solar model as the cause of the solar-neutrino problem, and also as a means of distinguishing between different sets of oscillation parameters

  4. A model-independent approach to the search for the sun neutrino oscillations from SNO data

    International Nuclear Information System (INIS)

    Beshtoev, Kh.M.

    1996-01-01

    A model-independent approach to analyse the existence of the Sun neutrino oscillations from SNO data is proposed. The used approximations for the calculations are offered as well as a scheme to determine the existence of the neutrino oscillations

  5. Adiabatic resonant oscillations of solar neutrinos in three generations

    International Nuclear Information System (INIS)

    Kim, C.W.; Sze, W.K.

    1987-01-01

    The Mikheyev-Smirnov-Wolfenstein model of resonant solar-neutrino oscillations is discussed for three generations of leptons. Assuming adiabatic transitions, bounds for the μ- and e-neutrinos mass-squared difference Δ/sub 21,0/ are obtained as a function of the e-μ mixing angle theta 1 . The allowed region in the Δ/sub 21,0/-theta 1 plot that would solve the solar-neutrino problem is shown to be substantially larger than that of the two-generation case. In particular, the difference between the two- and three-generation cases becomes significant for theta 1 larger than --20 0

  6. Entanglement in a QFT Model of Neutrino Oscillations

    International Nuclear Information System (INIS)

    Illuminati, F.; Blasone, M.; Dell’Anno, F.; De Siena, S.

    2014-01-01

    Tools of quantum information theory can be exploited to provide a convenient description of the phenomena of particle mixing and flavor oscillations in terms of entanglement, a fundamental quantum resource. We extend such a picture to the domain of quantum field theory where, due to the nontrivial nature of flavor neutrino states, the presence of antiparticles provides additional contributions to flavor entanglement. We use a suitable entanglement measure, the concurrence, that allows extracting the two-mode (flavor) entanglement from the full multimode, multiparticle flavor neutrino states

  7. The Use of Low Temperature Detectors for Direct Measurements of the Mass of the Electron Neutrino

    Directory of Open Access Journals (Sweden)

    A. Nucciotti

    2016-01-01

    Full Text Available Recent years have witnessed many exciting breakthroughs in neutrino physics. The detection of neutrino oscillations has proved that neutrinos are massive particles, but the assessment of their absolute mass scale is still an outstanding challenge in today particle physics and cosmology. Since low temperature detectors were first proposed for neutrino physics experiments in 1984, there has been tremendous technical progress: today this technique offers the high energy resolution and scalability required to perform competitive experiments challenging the lowest electron neutrino masses. This paper reviews the thirty-year effort aimed at realizing calorimetric measurements with sub-eV neutrino mass sensitivity using low temperature detectors.

  8. Synergies between neutrino oscillation experiments: an ‘adequate’ configuration for LBNO

    International Nuclear Information System (INIS)

    Ghosh, Monojit; Ghoshal, Pomita; Goswami, Srubabati; Raut, Sushant K.

    2014-01-01

    Determination of the neutrino mass hierarchy, octant of the mixing angle θ 23 and the CP violating phase δ CP are the unsolved problems in neutrino oscillation physics today. In this paper our aim is to obtain the minimum exposure required for the proposed Long Baseline Neutrino Oscillation (LBNO) experiment to determine the above unknowns. We emphasize on the advantage of exploiting the synergies offered by the existing and upcoming long-baseline and atmospheric neutrino experiments in economising the LBNO configuration. In particular, we do a combined analysis for LBNO, T2K, NOνA and INO. We consider three prospective LBNO setups — CERN-Pyhäsalmi (2290 km), CERN-Slanic (1500 km) and CERN-Fréjus (130 km) and evaluate the adequate exposure required in each case. Our analysis shows that the exposure required from LBNO can be reduced considerably due to the synergies arising from the inclusion of the other experiments

  9. Constraining neutrino magnetic moment with solar and reactor neutrino data

    OpenAIRE

    Tortola, M. A.

    2004-01-01

    We use solar neutrino data to derive stringent bounds on Majorana neutrino transition moments (TMs). Such moments, if present, would contribute to the neutrino-electron scattering cross section and hence alter the signal observed in Super-Kamiokande. Using the latest solar neutrino data, combined with the results of the reactor experiment KamLAND, we perform a simultaneous fit of the oscillation parameters and TMs. Furthermore, we include data from the reactor experiments Rovno, TEXONO and MU...

  10. Prospects of light sterile neutrino oscillation and C P violation searches at the Fermilab Short Baseline Neutrino Facility

    Science.gov (United States)

    Cianci, D.; Furmanski, A.; Karagiorgi, G.; Ross-Lonergan, M.

    2017-09-01

    We investigate the ability of the short baseline neutrino (SBN) experimental program at Fermilab to test the globally-allowed (3 +N ) sterile neutrino oscillation parameter space. We explicitly consider the globally-allowed parameter space for the (3 +1 ), (3 +2 ), and (3 +3 ) sterile neutrino oscillation scenarios. We find that SBN can probe with 5 σ sensitivity more than 85%, 95% and 55% of the parameter space currently allowed at 99% confidence level for the (3 +1 ), (3 +2 ) and (3 +3 ) scenarios, respectively, with the (3 +N ) allowed space used in these studies closely resembling that of previous studies [J. M. Conrad, C. M. Ignarra, G. Karagiorgi, M. H. Shaevitz, and J. Spitz, Adv. High Energy Phys. 2013, 1 (2013)., 10.1155/2013/163897], calculated using the same methodology. In the case of the (3 +2 ) and (3 +3 ) scenarios, C P -violating phases appear in the oscillation probability terms, leading to observable differences in the appearance probabilities of neutrinos and antineutrinos. We explore SBN's sensitivity to those phases for the (3 +2 ) scenario through the currently planned neutrino beam running, and investigate potential improvements through additional antineutrino beam running. We show that, if antineutrino exposure is considered, for maximal values of the (3 +2 ) C P -violating phase ϕ54, SBN could be the first experiment to directly observe ˜2 σ hints of C P violation associated with an extended lepton sector.

  11. Precision Measurement of the Beryllium-7 Solar Neutrino Interaction Rate in Borexino

    Science.gov (United States)

    Saldanha, Richard Nigel

    Solar neutrinos, since their first detection nearly forty years ago, have revealed valuable information regarding the source of energy production in the Sun, and have demonstrated that neutrino oscillations are well described by the Large Mixing Angle (LMA) oscillation parameters with matter interactions due to the Mikheyev-Smirnov-Wolfenstein (MSW) effect. This thesis presents a precision measurement of the 7Be solar neutrino interaction rate within Borexino, an underground liquid scintillator detector that is designed to measure solar neutrino interactions through neutrino-electron elastic scattering. The thesis includes a detailed description of the analysis techniques developed and used for this measurement as well as an evaluation of the relevant systematic uncertainties that affect the precision of the result. The rate of neutrino-electron elastic scattering from 0.862 MeV 7Be neutrinos is determined to be 45.4 +/- 1.6 (stat) +/- 1.5 (sys) counts/day/100 ton. Due to extensive detector calibrations and improved analysis methods, the systematic uncertainty in the interaction rate has been reduced by more than a factor of two from the previous evaluation. In the no-oscillation hypothesis, the interaction rate corresponds to a 0.862 MeV 7Be electron neutrino flux of (2.75 +/- 0.13) x 10 9 cm-2 sec-1. Including the predicted neutrino flux from the Standard Solar Model yields an electron neutrino survival probability of Pee 0.51 +/- 0.07 and rules out the no-oscillation hypothesis at 5.1sigma The LMA-MSW neutrino oscillation model predicts a transition in the solar Pee value between low ( 10 MeV) energies which has not yet been experimentally confirmed. This result, in conjunction with the Standard Solar Model, represents the most precise measurement of the electron neutrino survival probability for solar neutrinos at sub-MeV energies.

  12. The oscillation probability of GeV solar neutrinos of all active species

    International Nuclear Information System (INIS)

    Gouvea, Andre de

    2001-01-01

    I discuss the oscillation probability of O(GeV) neutrinos of all active flavours produced inside the Sun and detected at the Earth. In the GeV energy regime, matter effects are potentially important both for the ''1-3'' system and the ''1-2'' system. A numerical scan of the multidimensional three-flavour parameter space is presented. One curiosity is that in the three-flavour oscillation case P αβ ≠ P βα for a large portion of the parameter space, even if the MNS matrix is real. Oscillation effects computed here may play a large role in interpreting solar WIMP search data from large neutrino telescopes

  13. Matter suppression of collective SN neutrino oscillations and stability analysis

    International Nuclear Information System (INIS)

    Saviano, N.; Chakraborty, S.; Mirizzi, A.

    2014-01-01

    We perform a detailed analysis of the supernova (SN) neutrino flavor evolution during the early time accretion phase (post-bounce time t pb ≤ 500 ms), characterizing the ν signal by recent SN hydrodynamics simulations. We find that collective oscillations induced the ν-ν interactions in the deepest SN regions are suppressed by trajectory-dependent 'multi-angle' effects associated with the dense ordinary matter. We confirm this result with a linearized stability analysis of the neutrino equations of motion in presence of realistic neutrino energy with angle distributions. (authors)

  14. Status of the Daya Bay Reactor Neutrino Oscillation Experiment

    International Nuclear Information System (INIS)

    Lin, Cheng-Ju Stephen

    2010-01-01

    The last unknown neutrino mixing angle θ 13 is one of the fundamental parameters of nature; it is also a crucial parameter for determining the sensitivity of future long-baseline experiments aimed to study CP violation in the neutrino sector. Daya Bay is a reactor neutrino oscillation experiment designed to achieve a sensitivity on the value of sin 2 (2*θ 13 ) to better than 0.01 at 90% CL. The experiment consists of multiple identical detectors placed underground at different baselines to minimize systematic errors and suppress cosmogenic backgrounds. With the baseline design, the expected anti-neutrino signal at the far site is about 360 events per day and at each of the near sites is about 1500 events per day. An overview and current status of the experiment will be presented.

  15. High intensity neutrino oscillation facilities in Europe

    Directory of Open Access Journals (Sweden)

    T. R. Edgecock

    2013-02-01

    Full Text Available The EUROnu project has studied three possible options for future, high intensity neutrino oscillation facilities in Europe. The first is a Super Beam, in which the neutrinos come from the decay of pions created by bombarding targets with a 4 MW proton beam from the CERN High Power Superconducting Proton Linac. The far detector for this facility is the 500 kt MEMPHYS water Cherenkov, located in the Fréjus tunnel. The second facility is the Neutrino Factory, in which the neutrinos come from the decay of μ^{+} and μ^{-} beams in a storage ring. The far detector in this case is a 100 kt magnetized iron neutrino detector at a baseline of 2000 km. The third option is a Beta Beam, in which the neutrinos come from the decay of beta emitting isotopes, in particular ^{6}He and ^{18}Ne, also stored in a ring. The far detector is also the MEMPHYS detector in the Fréjus tunnel. EUROnu has undertaken conceptual designs of these facilities and studied the performance of the detectors. Based on this, it has determined the physics reach of each facility, in particular for the measurement of CP violation in the lepton sector, and estimated the cost of construction. These have demonstrated that the best facility to build is the Neutrino Factory. However, if a powerful proton driver is constructed for another purpose or if the MEMPHYS detector is built for astroparticle physics, the Super Beam also becomes very attractive.

  16. Strongest gravitational waves from neutrino oscillations at supernova core bounce

    International Nuclear Information System (INIS)

    Mosquera Cuesta, H.J.; Fiuza, K.

    2004-01-01

    Resonant active-to-active (ν a →ν a ), as well as active-to-sterile (ν a →ν s ) neutrino (ν) oscillations can take place during the core bounce of a supernova collapse. Besides, over this phase, weak magnetism increases the antineutrino (anti ν) mean free path, and thus its luminosity. Because the oscillation feeds mass-energy into the target ν species, the large mass-squared difference between the species (ν a →ν s ) implies a huge amount of energy to be given off as gravitational waves (L GW ∝10 49 erg s -1 ), due to anisotropic but coherent ν flow over the oscillation length. This asymmetric ν-flux is driven by both the spin-magnetic and the universal spin-rotation coupling. The novel contribution of this paper stems from (1) the new computation of the anisotropy parameter α∝0.1-0.01, and (2) the use of the tight constraints from neutrino experiments as SNO and KamLAND, and the cosmic probe WMAP, to compute the gravitational-wave emission during neutrino oscillations in supernovae core collapse and bounce. We show that the mass of the sterile neutrino ν s that can be resonantly produced during the flavor conversions makes it a good candidate for dark matter as suggested by Fuller et al., Phys. Rev. D 68, 103002 (2003). The new spacetime strain thus estimated is still several orders of magnitude larger than those from ν diffusion (convection and cooling) or quadrupole moments of neutron star matter. This new feature turns these bursts into the more promising supernova gravitational-wave signals that may be detected by observatories as LIGO, VIRGO, etc., for distances far out to the VIRGO cluster of galaxies. (orig.)

  17. Introduction to the phenomenology of neutrino oscillations

    International Nuclear Information System (INIS)

    Snellman, H.

    2001-01-01

    These notes are aimed at introducing the freshman into the phenomenology of neutrino oscillations. I apologize to all of those that are not properly quoted in these notes. Several excellent reviews of the field exist and some are listed at the end of these notes, where appropriate references to works not included in these notes can be found. (orig.)

  18. Precision Measurement of Neutrino Oscillation Parameters with KamLAND

    Energy Technology Data Exchange (ETDEWEB)

    O' Donnell, Thomas [Univ. of California, Berkeley, CA (United States)

    2011-12-01

    This dissertation describes a measurement of the neutrino oscillation parameters m2 21, θ12 and constraints on θ13 based on a study of reactor antineutrinos at a baseline of ~ 180 km with the KamLAND detector. The data presented here was collected between April 2002 and November 2009, and amounts to a total exposure of 2.64 ± 0.07 × 1032 proton-years. For this exposure we expect 2140 ± 74(syst) antineutrino candidates from reactors, assuming standard model neutrino behavior, and 350±88(syst) candidates from background. The number observed is 1614. The ratio of background-subtracted candidates observed to expected is (NObs - NBkg)/ (NExp) = 0.59 ± 0.02(stat) ± 0.045(syst) which confirms reactor neutrino disappearance at greater than 5σ significance. Interpreting this deficit as being due to neutrino oscillation, the best-fit oscillation parameters from a three-flavor analysis are m2 21= 7.60+0.20 -0.19×10-5eV2, θ12 = 32.5 ± 2.9 degrees and sin2 θ13 = 0.025+0.035 -0.035, the 95% confidence-level upper limit on sin2 θ13 is sin2 θ13 < 0.083. Assuming CPT invariance, a combined analysis of KamLAND and solar neutrino data yields best-fit values: m2 21 = 7.60+0.20 -0.20 × 10-5eV2, θ12 = 33.5+1.0 -1.1 degrees, and sin2 θ13 = 0.013 ± 0.028 or sin2 θ13 < 0.06 at the 95% confidence level.

  19. Investigation of alternative mechanisms to neutrino oscillations in the MINOS experiment; Investigacao de Mecanismos Alternativos a Oscilacao de Neutrinos no Experimentos MINOS

    Energy Technology Data Exchange (ETDEWEB)

    de Abreu Barbosa Coelho, Joao [Campinas State Univ., Sao Paulo (Brazil)

    2012-01-01

    The neutrino oscillation model is very successful in explaining a large variety of experiments. The model is based on the premise that the neutrinos that interact through the weak force via charged current are not mass eigenstates, but a superposition of them. In general, a quantum superposition is subject to loss of coherence, so that pure states tend toward mixed states. This type of evolution is not possible within the context of isolated quantum systems because the evolution is unitary and, therefore, is invariant under time reversal. By breaking unitarity, an arrow of time is introduced and the characteristic effect for neutrinos is a damping of oscillations. In this thesis, some phenomenological decoherence and decay models are investigated, which could be observed by MINOS, a neutrino oscillation experiment that consists of measuring the neutrino flux produced in a particle accelerator 735 km away. We analyse the disappearance of muon neutrinos in MINOS. Information from other experiments is used to constrain the number of parameters, leaving only one extra parameter in each model. We assume a power law energy dependence of the decoherence parameter. The official MINOS software and simulation are used to obtain the experiment's sensitivities to the effects of unitarity breaking considered.

  20. NOvA Short-Baseline Tau Neutrino Appearance Search

    Energy Technology Data Exchange (ETDEWEB)

    Keloth, Rijeesh [Cochin U.; Aurisano, Adam [Cincinnati U.; Sousa, Alexander [Cincinnati U.; Davies, Gavin S [Indiana U.; Suter, Louise [Fermilab; Plunkett, Robert K [Fermilab

    2017-10-01

    Standard three-flavor neutrino oscillations have well explained by a wide range of neutrino experiments. However, the anomalous results, such as electron-antineutrino excess seen by LSND and MiniBooNE do not fit the three-flavor paradigm. This can be explained by an additional fourth flavor sterile neutrino at a larger scale than the existing three flavor neutrinos. The NOvA experiment consists of two finely segmented, liquid scintillator detectors operating 14 .6 mrad off-axis from the NuMI muon-neutrino beam. The Near Detector is located on the Fermilab campus, 1 km from the NuMI target, while the Far Detector is located at Ash River, MN, 810 km from the NuMI target. The NOvA experiment is primarily designed to measure electron-neutrino appearance at the Far Detector using the Near Detector to control systematic uncertainties; however, the Near Detector is well suited for searching for anomalous short-baseline oscillations. This poster will present a novel method for selecting tau neutrino interactions with high purity at the Near Detector using a convolutional neural network. Using this method, the sensitivity to anomalous short-baseline tau-neutrino appearance due to sterile neutrino oscillations will be presented.

  1. New neutrino physics and the altered shapes of solar neutrino spectra

    Science.gov (United States)

    Lopes, Ilídio

    2017-01-01

    Neutrinos coming from the Sun's core have been measured with high precision, and fundamental neutrino oscillation parameters have been determined with good accuracy. In this work, we estimate the impact that a new neutrino physics model, the so-called generalized Mikheyev-Smirnov-Wolfenstein (MSW) oscillation mechanism, has on the shape of some of leading solar neutrino spectra, some of which will be partially tested by the next generation of solar neutrino experiments. In these calculations, we use a high-precision standard solar model in good agreement with helioseismology data. We found that the neutrino spectra of the different solar nuclear reactions of the pp chains and carbon-nitrogen-oxygen cycle have quite distinct sensitivities to the new neutrino physics. The He P and 8B neutrino spectra are the ones in which their shapes are more affected when neutrinos interact with quarks in addition to electrons. The shapes of the 15O and 17F neutrino spectra are also modified, although in these cases the impact is much smaller. Finally, the impact in the shapes of the P P and 13N neutrino spectra is practically negligible.

  2. Solar opacities constrained by solar neutrinos and solar oscillations

    International Nuclear Information System (INIS)

    Cox, A.N.

    1989-01-01

    This review discusses the current situation for opacities at the solar center, the solar surface, and for the few million kelvin temperatures that occur below the convection zone. The solar center conditions are important because they are crucial for the neutrino production, which continues to be predicted about 4 times that observed. The main extinction effects there are free-free photon absorption in the electric fields of the hydrogen, helium and the CNO atoms, free electron scattering of photons, and the bound-free and bound-bound absorption of photons by iron atoms with two electrons in the 1s bound level. An assumption that the iron is condensed-out below the convection zone, and the opacity in the central regions is thereby reduced, results in about a 25 percent reduction in the central opacity but only a 5 percent reduction at the base of the convection zone. Furthermore, the p-mode solar oscillations are changed with this assumption, and do not fit the observed ones as well as for standard models. A discussion of the large effective opacity reduction by weakly interacting massive particles also results in poor agreement with observed p-mode oscillation frequencies. The much larger opacities for the solar surface layers from the Los Alamos Astrophysical Opacity Library instead of the widely used Cox and Tabor values show small improvements in oscillation frequency predictions, but the largest effect is in the discussion of p-mode stability. Solar oscillation frequencies can serve as an opacity experiment for the temperatures and densities, respectively, of a few million kelvin and between 0.1 and 10 g/cm 3 . Current oscillation frequency calculations indicate that possibly the Opacity Library values need an increase of typically 15 percent just at the bottom of the convection zone at 3 x 10 6 K. 41 refs., 15 figs., 1 tab

  3. Detection and reconstruction of short-lived particles produced by neutrino interactions in emulsion

    CERN Document Server

    Uiterwijk, J W E

    2007-01-01

    In this dissertation, several different topics related to the chorus experiment are pre- sented. The chorus experiment has been used to study neutrino oscillations using the neutrino beam at cern. The neutrino oscillation hypothesis provided an explanation for the lower than expected fluxes of solar and atmospheric neutrinos. There are three neutrino species in nature corresponding to different weak eigenstates, namely, the elec- tron neutrino (νe ), the muon neutrino (νμ ), and the tau neutrino (ντ ). The lower fluxes could be interpreted as spontaneous oscillations between electron and muon neutrinos and between muon and tau neutrinos. The chorus experiment was designed to detect oscillation of muon neutrinos into tau neutrinos with small mixing probability down to 2 · 10−4 and a mass difference square between νμ and ντ larger than 0.5 eV2 . In the last decade, several disappearance experiments have confirmed the neutrino oscillation hypothesis and showed that oscillations occur between mass eig...

  4. Quantum gravity signals in neutrino oscillations

    International Nuclear Information System (INIS)

    Sprenger, M.; Nicolini, P.; Bleicher, M.

    2011-01-01

    We investigate the effect of a Quantum Gravity-induced minimal length on neutrino oscillations. The minimal length is implemented in a phenomenological framework, allowing us to make predictions independently of any fundamental approach. We obtain clear minimal length signatures and discuss their observability in current and future experiments. We present an overview over other scenarios in which the minimal length leaves its signature and show new results concerning minimal length thermodynamics. (author)

  5. Gravitationally induced neutrino oscillation phases in static spacetimes

    International Nuclear Information System (INIS)

    Bhattacharya, T.; Habib, S.; Mottola, E.

    1999-01-01

    We critically examine the recent claim of a 'new effect' of gravitationally induced quantum mechanical phases in neutrino oscillations. Because this claim has generated some discussion in the literature we present here a straightforward calculation of the phase and clarify some of the conceptual issues involved, particularly in relation to the equivalence principle. When expressed in terms of the asymptotic energy of the neutrinos E and Schwarzschild radial coordinates r, the lowest order at which such a gravitational effect appears is (GMΔm 4 /ℎE 3 )ln(r B /r A ). copyright 1999 The American Physical Society

  6. A Sterile-Neutrino Search with the MINOS Experiment

    International Nuclear Information System (INIS)

    Rodrigues, Philip

    2010-01-01

    The MINOS experiment is a long-baseline neutrino oscillation experiment in the the NuMI beamline at Fermilab, USA. Using a near detector at 1 km distance from the neutrino production target, and a far detector at 735 km from the target, it is designed primarily to measure the disappearance of muon neutrinos. This thesis presents an analysis using MINOS data of the possibility of oscil- lation of the neutrinos in the NuMI beam to a hypothetical sterile flavour, which would have no Standard Model couplings. Such oscillations would result in a deficit in the neutral current interaction rate in the MINOS far detector relative to the expectation derived from the near detector data. The method used to identify neutral current and charged current events in the MINOS detectors is described and a new method of predicting and fitting the far detector spectrum presented, along with the effects of systematic uncertainties on the sterile neutrino oscillation analysis. Using this analysis, the fraction f s of the disappearing neutrinos that go to steriles is constrained to be below 0.15 at the 90% confidence level in the absence of electron neutrino appearance in the NuMI beam. With electron appearance at the CHOOZ limit, f s < 0.41 at 90% C.L.

  7. Using Quasi-Elastic Events to Measure Neutrino Oscillations with MINOS Detectors in the NuMI Neutrino Beam

    Energy Technology Data Exchange (ETDEWEB)

    Watabe, Masaki [Texas A & M Univ., College Station, TX (United States)

    2010-05-01

    MINOS (Main Injector Neutrino Oscillation Search) experiment has been designed to search for a change in the avor composition of a beam of muon neutrinos as they travel between the Near Detector at Fermi National Accelerator Laboratory and the Far Detector in the Soudan mine in Minnesota, 735 km from the target. The MINOS oscillation analysis is mainly performed with the charged current (CC) events and sensitive to constrain high- Δm2 values. However, the quasi-elastic (QEL) charged current interaction is dominant in the energy region important to access low- m2 values. For further improvement, the QEL oscillation analysis is performed in this dissertation. A data sample based on a total of 2.50 x 1020 POT is used for this analysis. In summary, 55 QEL-like events are observed at the Far detector while 87.06 ± 13.17 (syst:) events are expected with null oscillation hypothesis. These data are consistent with disappearance via oscillation with m2 = 2:10 0.37 (stat:) ± 0.24 (syst:) eV2 and the maximal mixing angle.

  8. Exploring flavor-dependent long-range forces in long-baseline neutrino oscillation experiments

    Science.gov (United States)

    Chatterjee, Sabya Sachi; Dasgupta, Arnab; Agarwalla, Sanjib Kumar

    2015-12-01

    The Standard Model gauge group can be extended with minimal matter content by introducing anomaly free U(1) symmetry, such as L e - L μ or L e - L τ . If the neutral gauge boson corresponding to this abelian symmetry is ultra-light, then it will give rise to flavor-dependent long-range leptonic force, which can have significant impact on neutrino oscillations. For an instance, the electrons inside the Sun can generate a flavor-dependent long-range potential at the Earth surface, which can suppress the ν μ → ν e appearance probability in terrestrial experiments. The sign of this potential is opposite for anti-neutrinos, and affects the oscillations of (anti-)neutrinos in different fashion. This feature invokes fake CP-asymmetry like the SM matter effect and can severely affect the leptonic CP-violation searches in long-baseline experiments. In this paper, we study in detail the possible impacts of these long-range flavor-diagonal neutral current interactions due to L e - L μ symmetry, when (anti-)neutrinos travel from Fermilab to Homestake (1300 km) and CERN to Pyhäsalmi (2290 km) in the context of future high-precision superbeam facilities, DUNE and LBNO respectively. If there is no signal of long-range force, DUNE (LBNO) can place stringent constraint on the effective gauge coupling α eμ < 1.9 × 10-53 (7.8 × 10-54) at 90% C.L., which is almost 30 (70) times better than the existing bound from the Super-Kamiokande experiment. We also observe that if α eμ ≥ 2 × 10-52, the CP-violation discovery reach of these future facilities vanishes completely. The mass hierarchy measurement remains robust in DUNE (LBNO) if α eμ < 5 × 10-52 (10-52).

  9. Introduction to a field-theoretical treatment of neutrino oscillations

    Indian Academy of Sciences (India)

    ... treatment of neutrino oscillations provides a beautiful and simple picture of ... This fact is best taken into account in the quantum field-theoretical approach where ..... which contain a real antineutrino of mass С , or in other words, in the limit Д.

  10. Fourier analysis of the parametric resonance in neutrino oscillations

    International Nuclear Information System (INIS)

    Koike, Masafumi; Ota, Toshihiko; Saito, Masako; Sato, Joe

    2009-01-01

    Parametric enhancement of the appearance probability of the neutrino oscillation under the inhomogeneous matter is studied. Fourier expansion of the matter density profile leads to a simple resonance condition and manifests that each Fourier mode modifies the energy spectrum of oscillation probability at around the corresponding energy; below the MSW resonance energy, a large-scale variation modifies the spectrum in high energies while a small-scale one does in low energies. In contrast to the simple parametric resonance, the enhancement of the oscillation probability is itself an slow oscillation as demonstrated by a numerical analysis with a single Fourier mode of the matter density. We derive an analytic solution to the evolution equation on the resonance energy, including the expression of frequency of the slow oscillation.

  11. Sterile neutrinos in light of recent cosmological and oscillation data: a multi-flavor scheme approach

    International Nuclear Information System (INIS)

    Melchiorri, Alessandro; Mena, Olga; Sorel, Michel; Palomares-Ruiz, Sergio; Pascoli, Silvia; Slosar, Anze

    2009-01-01

    Light sterile neutrinos might mix with the active ones and be copiously produced in the early Universe. In the present paper, a detailed multi-flavor analysis of sterile neutrino production is performed. Making some justified approximations allows us to consider not only neutrino interactions with the primeval medium and neutrino coherence breaking effects, but also oscillation effects arising from the presence of three light (mostly-active) neutrino states mixed with two heavier (mostly-sterile) states. First, we emphasize the underlying physics via an analytical description of sterile neutrino abundances that is valid for cases with small mixing between active and sterile neutrinos. Then, we study in detail the phenomenology of (3+2) sterile neutrino models in light of short-baseline oscillation data, including the LSND and MiniBooNE results. Finally, by using the information provided by this analysis, we obtain the expected sterile neutrino cosmological abundances and then contrast them with the most recent available data from Cosmic Microwave Background and Large Scale Structure observations. We conclude that (3+2) models are significantly more disfavored by the internal inconsistencies between sterile neutrino interpretations of appearance and disappearance short-baseline data themselves, rather than by the used cosmological data

  12. Measurement of neutrino flux from neutrino-electron elastic scattering

    Science.gov (United States)

    Park, J.; Aliaga, L.; Altinok, O.; Bellantoni, L.; Bercellie, A.; Betancourt, M.; Bodek, A.; Bravar, A.; Budd, H.; Cai, T.; Carneiro, M. F.; Christy, M. E.; Chvojka, J.; da Motta, H.; Dytman, S. A.; Díaz, G. A.; Eberly, B.; Felix, J.; Fields, L.; Fine, R.; Gago, A. M.; Galindo, R.; Ghosh, A.; Golan, T.; Gran, R.; Harris, D. A.; Higuera, A.; Kleykamp, J.; Kordosky, M.; Le, T.; Maher, E.; Manly, S.; Mann, W. A.; Marshall, C. M.; Martinez Caicedo, D. A.; McFarland, K. S.; McGivern, C. L.; McGowan, A. M.; Messerly, B.; Miller, J.; Mislivec, A.; Morfín, J. G.; Mousseau, J.; Naples, D.; Nelson, J. K.; Norrick, A.; Nuruzzaman; Osta, J.; Paolone, V.; Patrick, C. E.; Perdue, G. N.; Rakotondravohitra, L.; Ramirez, M. A.; Ray, H.; Ren, L.; Rimal, D.; Rodrigues, P. A.; Ruterbories, D.; Schellman, H.; Solano Salinas, C. J.; Tagg, N.; Tice, B. G.; Valencia, E.; Walton, T.; Wolcott, J.; Wospakrik, M.; Zavala, G.; Zhang, D.; Miner ν A Collaboration

    2016-06-01

    Muon-neutrino elastic scattering on electrons is an observable neutrino process whose cross section is precisely known. Consequently a measurement of this process in an accelerator-based νμ beam can improve the knowledge of the absolute neutrino flux impinging upon the detector; typically this knowledge is limited to ˜10 % due to uncertainties in hadron production and focusing. We have isolated a sample of 135 ±17 neutrino-electron elastic scattering candidates in the segmented scintillator detector of MINERvA, after subtracting backgrounds and correcting for efficiency. We show how this sample can be used to reduce the total uncertainty on the NuMI νμ flux from 9% to 6%. Our measurement provides a flux constraint that is useful to other experiments using the NuMI beam, and this technique is applicable to future neutrino beams operating at multi-GeV energies.

  13. Links between neutrino oscillations, leptogenesis, and proton decay ...

    Indian Academy of Sciences (India)

    accounts for the observed baryon asymmetry of the Universe by utilizing the process ... since the discoveries (confirmations) of the atmospheric [1] and solar neutrino oscil- lations [2,3] ... origin of their tiny masses may be at the root of the origin of matter-antimatter ..... Quite to the contrary, the minimal Higgs system provides.

  14. Solar neutrinos and nonradial solar oscillations

    International Nuclear Information System (INIS)

    Zatsepin, G.T.; Gavryuseva, E.A.; Kopysov, Yu.S.

    1980-01-01

    The problem of origin of surface solar oscillations is considered. It is assumed that generation of oscillations is performed by the solar nucleus. The necessary excitation condition for gravitational oscillations of the solar nucleus is a sharp decrease of the oscillation amplitude outside the nucleus, where the nuclear reaction rates are small and only radiation losses are considerable. It is shown that the specific singularities of gravitational wave propagation in solar entrails permit to attain a significant reduction of the oscillation amplitude. The solar entrails can serve as an effective trap for gravitational waves, if the substance of the solar nucleus is close to the state of convectional equilibrium. In order that the g 1 quadrupole mode of the solar nucleus has a period of 2h 40 min and sharply decreases in the solar mantle, it is enough that only the external part of the solar nucleus is close to the state of convectional equilibrium. Closeness of the solar nucleus to the state of convectional equilibrium is an argument in favour of its periodic mixing. Periodic mixing of the solar nucleus can serve as a cause of a low counting rate of solar neutrinos in R.Davis chlorous detector

  15. Neutrino masses and mixing

    International Nuclear Information System (INIS)

    Fogli, G.

    1998-01-01

    The paper presents an analysis of the solar neutrino problem in terms of both Mikheyev-Smirnov-Wolfenstein (MSW) and vacuum neutrino oscillations, with the inclusion of the data collected by the SuperKamiokande experiment during 306.3 days of operation. In particular, the observed energy spectrum of the recoil electrons from 8 B neutrino scattering is discussed in detail and used to constrain the mass-mixing parameter space. Going to the atmospheric neutrino anomaly, the paper performs both a two- and three-flavor analysis of the most recent SuperKamiokande atmospheric neutrino data. The variations of the zenith distributions of ν events in the presence of flavor oscillations are investigated. It is seen that fits to the SK data, with and without the addition of the CHOOZ constrains, strongly limit the parameter space. Detailed bounds in triangle graphs are reported

  16. First results with the experimental set-up at a Bugey reactor: neutrino oscillations, search of axions

    International Nuclear Information System (INIS)

    Hoummada, A.

    1982-07-01

    This work presents an experimental set-up at the Bugey PWR reactor to put into evidence neutrino oscillations. The first part describes a neutrino detector specially designed for the investigation of neutrino oscillations at two distances (13.50 m and 19 m) under the core of the reactor. Preliminary analysis are presented. The second part reports a search for axions, using the neutrino detector well-shielded volume. Created in competition with electro magnetic transitions, axion should be produced in abondance in the reactor core. This experiment excludes the existence of the axion of the standard model [fr

  17. Proposal to Measure Hadron Scattering with a Gaseous High Pressure TPC for Neutrino Oscillation Measurements

    CERN Document Server

    Andreopoulos, C; Bordoni, S; Boyd, S; Brailsford, D; Brice, S; Catanesi, G; Chen-Wishart, Z; Denner, P; Dunne, P; Giganti, C; Gonzalez Diaz, D; Haigh, J; Hamacher-Baumann, P; Hallsjo, S; Hayato, Y; Irastorza, I; Jamieson, B; Kaboth, A; Korzenev, A; Kudenko, Y; Leyton, M; Luk, K-B; Ma, W; Mahn, K; Martini, M; McCauley, N; Mermod, P; Monroe, J; Mosel, U; Nichol, R; Nieves, J; Nonnenmacher, T; Nowak, J; Parker, W; Raaf, J; Rademacker, J; Radermacher, T; Radicioni, E; Roth, S; Saakyan, R; Sanchez, F; Sgalaberna, D; Shitov, Y; Sobczyk, J; Soler, F; Touramanis, C; Valder, S; Walding, J; Ward, M; Wascko, M; Weber, A; Yokoyama, M; Zalewska, A; Ziembicki, M

    2017-01-01

    We propose to perform new measurements of proton and pion scattering on argon using a prototype High Pressure gas Time Projection Chamber (HPTPC) detector, and by doing so to develop the physics case for, and the technological readiness of, an HPTPC as a neutrino detector for accelerator neutrino oscillation searches. The motivation for this work is to improve knowledge of final state interactions, in order to ultimately achieve 1-2% systematic error on neutrino-nucleus scattering for oscillation measurements at 0.6 GeV and 2.5 GeV neutrino energy, as required for the Charge-Parity (CP) violation sensitivity projections by the Hyper-Kamiokande experiment (Hyper-K) and the Deep Underground Neutrino Experiment (DUNE). The final state interaction uncertainties in neutrino-nucleus interactions dominate cross-section systematic errors, currently 5–10% at these energies, and therefore R&D is needed to explore new approaches to achieve this substantial improvement.

  18. Detecting CP violation in a single neutrino oscillation channel at very long baselines

    International Nuclear Information System (INIS)

    Latimer, D. C.; Escamilla, J.; Ernst, D. J.

    2007-01-01

    We propose a way of detecting CP violation in a single neutrino oscillation channel at very long baselines (on the order of several thousands of kilometers), given precise knowledge of the smallest mass-squared difference. It is shown that CP violation can be characterized by a shift in L/E of the peak oscillation in the ν e -ν μ appearance channel, both in vacuum and in matter. In fact, matter effects enhance the shift at a fixed energy. We consider the case in which sub-GeV neutrinos are measured with varying baseline and also the case of a fixed baseline. For the varied baseline, accurate knowledge of the absolute neutrino flux would not be necessary; however, neutrinos must be distinguishable from antineutrinos. For the fixed baseline, it is shown that CP violation can be distinguished if the mixing angle θ 13 were known

  19. Possible energy dependence of Θ13 in neutrino oscillations

    International Nuclear Information System (INIS)

    Klinkhamer, Frans R.

    2005-01-01

    A simple three-flavor neutrino-oscillation model is discussed which has both nonzero mass differences and timelike Fermi-point splittings, together with a combined bi-maximal and trimaximal mixing pattern. One possible consequence would be new effects in ν μ →ν e oscillations, characterized by an energy-dependent effective mixing angle Θ 13 . Future experiments such as T2K and NOνA, and perhaps even the current MINOS experiment, could look for these effects

  20. A Sterile-Neutrino Search with the MINOS Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Philip [Univ. of Oxford (United Kingdom)

    2010-01-01

    The MINOS experiment is a long-baseline neutrino oscillation experiment in the the NuMI beamline at Fermilab, USA. Using a near detector at 1 km distance from the neutrino production target, and a far detector at 735 km from the target, it is designed primarily to measure the disappearance of muon neutrinos. This thesis presents an analysis using MINOS data of the possibility of oscil- lation of the neutrinos in the NuMI beam to a hypothetical sterile flavour, which would have no Standard Model couplings. Such oscillations would result in a deficit in the neutral current interaction rate in the MINOS far detector relative to the expectation derived from the near detector data. The method used to identify neutral current and charged current events in the MINOS detectors is described and a new method of predicting and fitting the far detector spectrum presented, along with the effects of systematic uncertainties on the sterile neutrino oscillation analysis. Using this analysis, the fraction fs of the disappearing neutrinos that go to steriles is constrained to be below 0.15 at the 90% confidence level in the absence of electron neutrino appearance in the NuMI beam. With electron appearance at the CHOOZ limit, fs < 0.41 at 90% C.L.

  1. Neutrino oscillations from discrete non-Abelian family symmetries

    International Nuclear Information System (INIS)

    Schmaltz, M.

    1995-01-01

    I disuss a SUSY GUT model with a non-Abelian discrete family symmetry that explains the observed hierarchical pattern of quark and lepton masses. This SO(10)xΔ(75) model predicts modified quadratic seesaw neutrino masses and mixing angles which are interesting for three reasons: (i) they offer a solution to the solar neutrino problem, (ii) the τ neutrino has the right mass for a cosmologically interesting hot dark matter candidate, and (iii) they suggest a positive result for the ν μ →ν τ oscillation searches by the CHORUS and NOMAD Collaborations. However, the model shares some problems with many other predictive GUT models of quark and lepton masses. The predictions from well-known mass and angle relations, such as the relation λ b GUT =λ τ GUT , fail in many cases. Attempts to correct these relations seem to lead to rather contrived models

  2. Neutrino burst from SN1987A and the solar-neutrino puzzle

    International Nuclear Information System (INIS)

    Arafune, J.; Fukugita, M.; Yanagida, T.; Yoshimura, M.

    1987-01-01

    The prompt ν/sub e/ signal from the supernova explosion in the Large Magellanic Cloud presumably detected by Kamiokande II does not necessarily mean that the Mikheyev-Smirnov-Wolfenstein effect on the solar-neutrino flux is not operative. The electron neutrino, once rotated to a different-flavor neutrino in the progenitor star, can come back via the matter-oscillation effect in the Earth, or a residual ν/sub e/ flux from the progenitor can directly hit the detector, saving the Mikheyev-Smirnov-Wolfenstein explanation of the solar-neutrino problem for a range of mixing parameters

  3. Sterile neutrino search in the STEREO experiment

    Energy Technology Data Exchange (ETDEWEB)

    Buck, Christian; Lindner, Manfred; Roca, Christian [MPIK (Germany)

    2016-07-01

    In neutrino oscillations, a canonical understanding has been established during the last decades after the measurement of the mixing angles θ{sub 12}, θ{sub 23}, θ{sub 13} via solar, atmospheric and, most recently, reactor neutrinos. However, the re-evaluation of the reactor neutrino theoretical flux has forced a re-analysis of most reactor neutrino measurements at short distances. This has led to an unexpected experimental deficit of neutrinos with respect to the theory that needs to be accommodated, commonly known as the ''reactor neutrino anomaly''. This deficit can be interpreted as the existence of a light sterile neutrino state into which reactor neutrinos oscillate at very short distances. The STEREO experiment aims to find an evidence of such oscillations. The ILL research reactor in Grenoble (France) operates at a power of 58MW and provides a large flux of electron antineutrinos with an energy range of a few MeV. These neutrinos will be detected in a 2000 liter organic liquid scintillator detector doped with Gadolinium and consisting of 6 cells stacked along the direction of the core. Given the proximity of the detector, neutrinos will only travel a few meters until they interact with the scintillator. The detector will be placed about 10 m from the reactor core, allowing STEREO to be sensitive to oscillations into the above mentioned neutrino sterile state. The project presents a high potential for a discovery that would impact deeply the paradigms of neutrino oscillations and in consequence the current understanding of particle physics and cosmology.

  4. Neutrinos oscillations researches near a nuclear reactor

    International Nuclear Information System (INIS)

    Laiman, M.

    1999-01-01

    This thesis deals with the research of neutrinos oscillations near the Chooz B nuclear power plant in the Ardennes. The first part presents the framework of the researches and the chosen detector. The second part details the antineutrinos flux calculus from the reactors and the calculus of the expected events. The analysis procedure is detailed in the last part from the calibration to the events selection. (A.L.B.)

  5. A framework for testing leptonic unitarity by neutrino oscillation experiments

    Energy Technology Data Exchange (ETDEWEB)

    Fong, Chee Sheng [Instituto de Física, Universidade de São Paulo,C.P. 66.318, 05315-970 São Paulo (Brazil); Minakata, Hisakazu [Department of Physics, Yachay Tech,San Miguel de Urcuquí, 100119 (Ecuador); Nunokawa, Hiroshi [Departamento de Física, Pontifícia Universidade Católica do Rio de Janeiro,C.P. 38097, 22451-900, Rio de Janeiro (Brazil)

    2017-02-22

    If leptonic unitarity is violated by new physics at an energy scale much lower than the electroweak scale, which we call low-scale unitarity violation, it has different characteristic features from those expected in unitarity violation at high-energy scales. They include maintaining flavor universality and absence of zero-distance flavor transition. We present a framework for testing such unitarity violation at low energies by neutrino oscillation experiments. Starting from the unitary 3 active plus N (arbitrary positive integer) sterile neutrino model we show that by restricting the active-sterile and sterile-sterile neutrino mass squared differences to ≳ 0.1 eV{sup 2} the oscillation probability in the (3+N) model becomes insensitive to details of the sterile sector, providing a nearly model-independent framework for testing low-scale unitarity violation. Yet, the presence of the sterile sector leaves trace as a constant probability leaking term, which distinguishes low-scale unitarity violation from the high-scale one. The non-unitary mixing matrix in the active neutrino subspace is common for the both cases. We analyze how severely the unitarity violation can be constrained in ν{sub e}-row by taking a JUNO-like setting to simulate medium baseline reactor experiments. Possible modification of the features of the (3+N) model due to matter effect is discussed to first order in the matter potential.

  6. Neutrino observations from the Sudbury Neutrino Observatory

    Energy Technology Data Exchange (ETDEWEB)

    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.

  7. Neutrino Observations from the Sudbury Neutrino Observatory

    Science.gov (United States)

    Q. R. Ahmad, R. C. Allen, T. C. Andersen, J. D. Anglin, G. B?hler, J. C. Barton, E. W. Beier, M. Bercovitch, J. Bigu, S. 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, T. H. Burritt, K. Cameron, J. Cameron, Y. D. Chan, M. Chen, H. H. Chen, X. Chen, M. C. Chon, B. T. Cleveland, E. T. H. Clifford, J. H. M. Cowan, D. F. Cowen, G. A. Cox, Y. Dai, X. Dai, F. Dalnoki-Veress, W. F. Davidson, P. J. Doe, G. Doucas, M. R. Dragowsky, C. A. Duba, F. A. Duncan, J. Dunmore, E. D. Earle, S. R. Elliott, H. C. Evans, G. T. Ewan, J. Farine, H. Fergani, A. P. Ferraris, R. J. Ford, M. M. Fowler, K. Frame, E. D. Frank, W. Frati, J. V. Germani, S. Gil, A. Goldschmidt, D. R. Grant, R. L. Hahn, A. L. Hallin, E. D. Hallman, A. Hamer, A. A. Hamian, R. U. Haq, C. K. Hargrove, P. J. Harvey, R. Hazama, R. Heaton, K. M. Heeger, W. J. Heintzelman, J. Heise, R. L. Helmer, J. D. Hepburn, H. Heron, J. Hewett, A. Hime, M. Howe, J. G. Hykawy, M. C. P. Isaac, P. Jagam, N. A. Jelley, C. Jillings, G. Jonkmans, J. Karn, P. T. Keener, K. Kirch, 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, M. M. Lowry, S. Luoma, J. Lyon, S. Majerus, H. B. Mak, A. D. Marino, N. McCauley, A. B. McDonald, D. S. McDonald, K. McFarlane, G. McGregor, W. McLatchie, R. Meijer Drees, H. Mes, 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. O'Neill, 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, J. K. Rowley, V. L. Rusu, E. Saettler, K. K. Schaffer, A. Schuelke, M. H. Schwendener, H. Seifert, M. Shatkay, J. J. Simpson, D. Sinclair, P. Skensved, A. R. Smith, M. W. E. Smith, N. Starinsky, T. D. Steiger, R. G. Stokstad, R. S. Storey, B. Sur, R. Tafirout, N. Tagg, N. W. Tanner, R. K. Taplin, M. Thorman, P. Thornewell, P. T. Trent, Y. I. Tserkovnyak, R. Van Berg, R. G. Van de Water, C. J. Virtue, C. E. Waltham, J.-X. Wang, D. L. Wark, N. West, J. B. Wilhelmy, J. F. Wilkerson, J. Wilson, P. Wittich, J. M. Wouters, and M. Yeh

    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.

  8. Detectors for the MINOS long-baseline neutrino oscillation experiment

    International Nuclear Information System (INIS)

    Ayres, D.S.

    1996-01-01

    The MINOS long-baseline experiment will use an intense neutrino beam, generated by Fermilab''s Main Injector accelerator, and 730 km flight path to search for neutrino oscillations. The 10,000 ton MINOS far detector will utilize toroidally magnetized steel plates interleaved with track chambers to reconstruct event topologies and to measure the energies of the muons, hadrons and electromagnetic showers produced by neutrino interactions. The MINOS collaboration is currently developing three alternative technologies for the track chambers: ''Iarocci'' tubes (operated in either limited streamer or saturated proportional mode), RPC''s (with either glass or ABS plates), and scintillator (either liquid or plastic) with wavelength shifting fiber readout. The technology choice will be made in mid 1997 based on the projected performance and cost of the 32,000 m 2 active detector system

  9. Neutrino masses and oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Smirnov, A Yu

    1996-11-01

    New effects related to refraction of neutrinos in different media are reviewed and implication of the effects to neutrino mass and mixing are discussed. Patterns of neutrino masses and mixing implied by existing hints/bounds are described. Recent results on neutrino mass generation are presented. They include neutrino masses in SO(10) GUT`s and models with anomalous U(1), generation of neutrino mass via neutrino-neutralino mixing, models of sterile neutrino. (author). 95 refs, 9 figs.

  10. Monochromatic neutrino beams

    International Nuclear Information System (INIS)

    Bernabeu, Jose; Burguet-Castell, Jordi; Espinoza, Catalina; Lindroos, Mats

    2005-01-01

    In the last few years spectacular results have been achieved with the demonstration of non vanishing neutrino masses and flavour mixing. The ultimate goal is the understanding of the origin of these properties from new physics. In this road, the last unknown mixing [U e3 ] must be determined. If it is proved to be non-zero, the possibility is open for Charge Conjugation-Parity (CP) violation in the lepton sector. This will require precision experiments with a very intense neutrino source. Here a novel method to create a monochromatic neutrino beam, an old dream for neutrino physics, is proposed based on the recent discovery of nuclei that decay fast through electron capture. Such nuclei will generate a monochromatic directional neutrino beam when decaying at high energy in a storage ring with long straight sections. We also show that the capacity of such a facility to discover new physics is impressive, so that fine tuning of the boosted neutrino energy allows precision measurements of the oscillation parameters even for a [U e3 ] mixing as small as 1 degree. We can thus open a window to the discovery of CP violation in neutrino oscillations

  11. Is CP violation observable in long baseline neutrino oscillation experiments?

    International Nuclear Information System (INIS)

    Tanimoto, M.

    1997-01-01

    We have studied CP violation originating from the phase of the neutrino-mixing matrix in the long baseline neutrino oscillation experiments. The direct measurement of CP violation is the difference of the transition probabilities between CP-conjugate channels. In those experiments, the CP-violating effect is not suppressed if the highest neutrino mass scale is taken to be 1 endash 5 eV, which is appropriate for the cosmological hot dark matter. Assuming the hierarchy for the neutrino masses, the upper bounds of CP violation have been calculated for three cases, in which mixings are constrained by the recent short baseline ones. The calculated upper bounds are larger than 10 -2 , which will be observable in the long baseline accelerator experiments. The matter effect, which is not CP invariant, has been also estimated in those experiments. copyright 1997 The American Physical Society

  12. Neutrino oscillations from discrete non-Abelian family symmetries

    International Nuclear Information System (INIS)

    Schmaltz, M.

    1994-11-01

    The author discusses a SUSY-GUT model with a non-Abelian discrete family symmetry that explains the observed hierarchical pattern of quark and lepton masses. This SO(10) x Δ(75) model predicts modified quadratic seesaw neutrino masses and mixing angles which are interesting for three reasons: (1) they offer a solution to the solar neutrino problem, (2) the tau neutrino has the right mass for a cosmologically interesting hot dark matter candidate, and (3) they suggest a positive result for the ν μ → ν τ oscillation searches by the CHORUS and NOMAD collaborations. However, the model shares some problems with many other predictive GUT models of quark and lepton masses. Well-known and once successful mass and angle relations, such as the SU(5) relation λ b GUT = λ t GUT , are found to be in conflict with the current experimental status. Attempts to correct these relations seem to lead to rather contrived models

  13. Neutrino oscillations in magnetically driven supernova explosions

    Energy Technology Data Exchange (ETDEWEB)

    Kawagoe, Shio; Kotake, Kei [Division of Theoretical Astronomy, National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo, 181-8588 (Japan); Takiwaki, Tomoya, E-mail: shio.k@nao.ac.jp, E-mail: takiwaki.tomoya@nao.ac.jp, E-mail: kkotake@th.nao.ac.jp [Center for Computational Astrophysics, National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo, 181-8588 (Japan)

    2009-09-01

    We investigate neutrino oscillations from core-collapse supernovae that produce magnetohydrodynamic (MHD) explosions. By calculating numerically the flavor conversion of neutrinos in the highly non-spherical envelope, we study how the explosion anisotropy has impacts on the emergent neutrino spectra through the Mikheyev-Smirnov-Wolfenstein effect. In the case of the inverted mass hierarchy with a relatively large θ{sub 13} (sin{sup 2} 2θ{sub 13} ∼> 10{sup −3}), we show that survival probabilities of ν-bar {sub e} and ν{sub e} seen from the rotational axis of the MHD supernovae (i.e., polar direction), can be significantly different from those along the equatorial direction. The event numbers of ν-bar {sub e} observed from the polar direction are predicted to show steepest decrease, reflecting the passage of the magneto-driven shock to the so-called high-resonance regions. Furthermore we point out that such a shock effect, depending on the original neutrino spectra, appears also for the low-resonance regions, which could lead to a noticeable decrease in the ν{sub e} signals. This reflects a unique nature of the magnetic explosion featuring a very early shock-arrival to the resonance regions, which is in sharp contrast to the neutrino-driven delayed supernova models. Our results suggest that the two features in the ν-bar {sub e} and ν{sub e} signals, if visible to the Super-Kamiokande for a Galactic supernova, could mark an observational signature of the magnetically driven explosions, presumably linked to the formation of magnetars and/or long-duration gamma-ray bursts.

  14. Neutrino oscillations in magnetically driven supernova explosions

    Science.gov (United States)

    Kawagoe, Shio; Takiwaki, Tomoya; Kotake, Kei

    2009-09-01

    We investigate neutrino oscillations from core-collapse supernovae that produce magnetohydrodynamic (MHD) explosions. By calculating numerically the flavor conversion of neutrinos in the highly non-spherical envelope, we study how the explosion anisotropy has impacts on the emergent neutrino spectra through the Mikheyev-Smirnov-Wolfenstein effect. In the case of the inverted mass hierarchy with a relatively large θ13 (sin2 2θ13 gtrsim 10-3), we show that survival probabilities of bar nue and νe seen from the rotational axis of the MHD supernovae (i.e., polar direction), can be significantly different from those along the equatorial direction. The event numbers of bar nue observed from the polar direction are predicted to show steepest decrease, reflecting the passage of the magneto-driven shock to the so-called high-resonance regions. Furthermore we point out that such a shock effect, depending on the original neutrino spectra, appears also for the low-resonance regions, which could lead to a noticeable decrease in the νe signals. This reflects a unique nature of the magnetic explosion featuring a very early shock-arrival to the resonance regions, which is in sharp contrast to the neutrino-driven delayed supernova models. Our results suggest that the two features in the bar nue and νe signals, if visible to the Super-Kamiokande for a Galactic supernova, could mark an observational signature of the magnetically driven explosions, presumably linked to the formation of magnetars and/or long-duration gamma-ray bursts.

  15. Oscillation sensitivity with up-going muons in lCAL at India based Neutrino Observatory (INO)

    International Nuclear Information System (INIS)

    Rawat, Kanishka; Bhatnagar, Vipin; Indumathi, D.

    2013-01-01

    The proposed magnetised Iron Calorimeter (ICAL) detector at the India-based Neutrino Observatory (INO) lab is mostly sensitive to the muon neutrinos. We present preliminary results for oscillation studies with up-going muons. We have used charge-current events with Honda flux for the analysis. Honda flux is calculated for INO-Theni site where the INO-ICAl detector will be placed. For up-going muon with 2-flavour oscillation, the parameters taken are: θ 12 = 34, θ 13 = 0, θ 23 = 45, Δm 2 31 = 7.92 x 10 -5 eV 2 , Δm 2 21 = 2.4 x 10 -3 eV 2 , δ cp = 0. We generate events using the ICAL geometry in the Nuance neutrino generator and pass the produced events through the ICAl-GEANT4 simulated detector. The muon tracks are reconstructed according to this package through a Kalman filter algorithm that returns both the magnitude and direction of the muon momentum. The sensitivity of these events to oscillations in the parent neutrino flux will be studied next

  16. Azimuthal asymmetry of recoil electrons in neutrino-electron elastic scattering as signature of neutrino nature

    Energy Technology Data Exchange (ETDEWEB)

    Sobkow, W.; Blaut, A. [University of Wroclaw, Institute of Theoretical Physics, Wroclaw (Poland)

    2016-05-15

    In this paper, we analyze the theoretically possible scenario beyond the standard model in order to show how the presence of the exotic scalar, tensor, V + A weak interactions in addition to the standard vector-axial (V - A) ones may help to distinguish the Dirac from Majorana neutrinos in the elastic scattering of an (anti)neutrino beam off the unpolarized electrons in the relativistic limit. We assume that the incoming (anti)neutrino beam comes from the polarized muon decay at rest and is the left-right chiral superposition with assigned direction of the transversal spin polarization with respect to the production plane. Our analysis is carried out for the flavour (current) neutrino eigenstates. It means that the transverse neutrino polarization estimates are the same both for the Dirac and Majorana cases. We display that the azimuthal asymmetry in the angular distribution of recoil electrons is generated by the interference terms between the standard and exotic couplings, which are proportional to the transversal (anti)neutrino spin polarization and independent of the neutrino mass. This asymmetry for the Majorana neutrinos is larger than for the Dirac ones. We also indicate the possibility of utilizing the azimuthal asymmetry measurements to search for the new CP-violating phases. Our study is based on the assumption that the possible detector (running for 1 year) has the shape of a flat circular ring, while the intense neutrino source is located in the centre of the ring and polarized perpendicularly to the ring. In addition, the large low-threshold, real-time detector is able to measure with a high resolution both the polar angle and the azimuthal angle of outgoing electron momentum. Our analysis is model-independent and consistent with the current upper limits on the non-standard couplings. (orig.)

  17. A short history of neutrinos, what we have learned about them, what we have learned using them, up to neutrino oscillations.”

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    This, the opening talk of the Kyoto conference, Neutrino 2012, attempts a brief review of the history of the neutrinos, up to neutrino oscillations, beginning with the discovery of the continuous β spectrum in 1914, to the demonstration of the tau neutrino in 2001, the contributions of the study of neutrino interactions to the evolution of the electroweak and the QCD theories, in particular the discovery of neutral currents, the demonstrations that the partons of nuclear structure are quarks, and the first quantitative confirmation of QCD in the scaling violations of deep inelastic scattering, and the structure functions of the nucleon.

  18. Physics potential of the CERN-MEMPHYS neutrino oscillation project

    International Nuclear Information System (INIS)

    Campagne, J.E.; Maltoni, M.; Mezzetto, M.; Schwetz, T.

    2006-03-01

    We consider the physics potential of CERN based neutrino oscillation experiments consisting of a Beta Beam (βB) and a Super Beam (SPL) sending neutrinos to MEMPHYS, a 440 kt water Cerenkov detector at Frejus, at a distance of 130 km from CERN. The θ 13 discovery reach and the sensitivity to CP violation are investigated, including a detailed discussion of parameter degeneracies and systematical errors. For βB and SPL sensitivities similar to the ones of the phase II of the T2K experiment (T2HK) are obtained, where the results for the CERN-MEMPHYS experiments are less affected by systematical uncertainties. We point out that by a combination of data from βB and SPL a measurement with antineutrinos is not necessary and hence the same physics results can be obtained within about half of the measurement time compared to one single experiment. Furthermore, it is shown how including data from atmospheric neutrinos in the MEMPHYS detector allows to resolve parameter degeneracies and, in particular, provides sensitivity to the neutrino mass hierarchy and the octant of θ 23 . (author)

  19. Neutrino oscillations with the full IceCube DeepCore detector

    Energy Technology Data Exchange (ETDEWEB)

    Yanez Garza, Juan Pablo [DESY, Zeuthen (Germany); Collaboration: IceCube-Collaboration

    2013-07-01

    The IceCube detector and its low energy extension, DeepCore, have recorded over 300,000 atmospheric neutrino events since completion almost two years ago. With an energy threshold of about 10 GeV and the possibility of observing different baselines between source and detector location, these events can be used to probe neutrino oscillations with unprecedented statistics. However, the measurement uncertainties, due to unknown properties of the detector and the medium where it stands, limit the sensitivity of such a study. The particular analysis under discussion is a special attempt to diminish the impact of systematic uncertainties while keeping a large high quality neutrino sample. The tools developed for it, as well as the current status of the analysis are presented.

  20. Parametric resonance in neutrino oscillation: A guide to control the effects of inhomogeneous matter density

    International Nuclear Information System (INIS)

    Koike, Masafumi; Ota, Toshihiko; Saito, Masako; Sato, Joe

    2016-01-01

    Effects of the inhomogeneous matter density on the three-generation neutrino oscillation probability are analyzed. Realistic profile of the matter density is expanded into a Fourier series. Taking in the Fourier modes one by one, we demonstrate that each mode has its corresponding target energy. The high Fourier mode selectively modifies the oscillation probability of the low-energy region. This rule is well described by the parametric resonance between the neutrino oscillation and the matter effect. The Fourier analysis gives a simple guideline to systematically control the uncertainty of the oscillation probability caused by the uncertain density of matter. Precise analysis of the oscillation probability down to the low-energy region requires accurate evaluation of the Fourier coefficients of the matter density up to the corresponding high modes.

  1. Neutrino Oscillations

    Indian Academy of Sciences (India)

    work of Takaaki Kajita and Arthur B McDonald clearly demon- strated the ... time belief that neutrinos are massless particles. .... SK is a second generation, 50,000 t wa- ..... values of the parameters of the PMNS matrix based on a global .... [13] Y Ashie et al., Evidence for an oscillatory signature in atmospheric neutrino.

  2. On the chaoticity of active-sterile neutrino oscillations in the early universe

    DEFF Research Database (Denmark)

    Braad, Poul-Erik; Hannestad, Steen

    2000-01-01

    We have investigated the evolution of the neutrino asymmetry in active-sterile neutrino oscillations in the early universe. We find that there are large regions of parameter space where the asymmetry is extremely sensitive to variations in the initial asymmetry as well as the external parameters ...... asymmetry is stochastic. We discuss the implications of our findings for Big Bang nucleosynthesis (BBN) and the cosmic microwave background (CMB)....

  3. Status and oscillation results of the OPERA experiment

    International Nuclear Information System (INIS)

    Brunet, F.

    2014-01-01

    The OPERA experiment, placed 730 km downstream the CERN neutrino beam to Gran Sasso (CNGS) in the LNGS underground laboratory, is designed to measure muon-neutrino to tau-neutrino oscillations in a direct appearance mode. The hybrid apparatus consists of an emulsion/lead target complemented by electronic detectors. Due to the target structure made of thin lead plates, OPERA is able to detect electromagnetic showers, allowing searches for tau electronic decays and for oscillations from muon-neutrino to electron-neutrino. The experimental set-up and associated facilities used to extract data recorded in the emulsion will be described, with the special procedures aimed at locating interaction vertices and detect short decay topologies. OPERA is taking data since 2008. A first nu-tau interaction candidate was already published in 2010. New results with increased statistics will be presented. In particular, an overview of the studies related to electrons will be shown. (author)

  4. Systematic uncertainties in long-baseline neutrino oscillations for large θ₁₃

    Energy Technology Data Exchange (ETDEWEB)

    Coloma, Pilar; Huber, Patrick; Kopp, Joachim; Winter, Walter

    2013-02-01

    We study the physics potential of future long-baseline neutrino oscillation experiments at large θ₁₃, focusing especially on systematic uncertainties. We discuss superbeams, \\bbeams, and neutrino factories, and for the first time compare these experiments on an equal footing with respect to systematic errors. We explicitly simulate near detectors for all experiments, we use the same implementation of systematic uncertainties for all experiments, and we fully correlate the uncertainties among detectors, oscillation channels, and beam polarizations as appropriate. As our primary performance indicator, we use the achievable precision in the measurement of the CP violating phase $\\deltacp$. We find that a neutrino factory is the only instrument that can measure $\\deltacp$ with a precision similar to that of its quark sector counterpart. All neutrino beams operating at peak energies ≳2 GeV are quite robust with respect to systematic uncertainties, whereas especially \\bbeams and \\thk suffer from large cross section uncertainties in the quasi-elastic regime, combined with their inability to measure the appearance signal cross sections at the near detector. A noteworthy exception is the combination of a γ =100 \\bbeam with an \\spl-based superbeam, in which all relevant cross sections can be measured in a self-consistent way. This provides a performance, second only to the neutrino factory. For other superbeam experiments such as \\lbno and the setups studied in the context of the \\lbne reconfiguration effort, statistics turns out to be the bottleneck. In almost all cases, the near detector is not critical to control systematics since the combined fit of appearance and disappearance data already constrains the impact of systematics to be small provided that the three active flavor oscillation framework is valid.

  5. Magnus expansion and three-neutrino oscillations in matter

    International Nuclear Information System (INIS)

    Cabral-Rosetti, L G; Aguilar-Arevalo, A A; D'Olivo, J C

    2006-01-01

    We present a semi-analytical derivation of the survival probability of solar neutrinos in the three generation scheme, based on the Magnus approximation of the evolution operator of a three level system, and assuming a mass hierarchy among neutrino mass eigenstates. We have used an exponential profile for the solar electron density in our approximation. The different interesting density regions that appear throughout the propagation are analyzed. Finally, some comments on the allowed regions in the solar neutrino parameter space are addressed

  6. Magnus expansion and three-neutrino oscillations in matter

    Energy Technology Data Exchange (ETDEWEB)

    Cabral-Rosetti, L G [Departamento de Posgrado, Centro Interdisciplinario de Investigacion y Docencia en Educacion Tecnica (CIIDET), Av. Universidad 282 Pte., Col. Centro, A. Postal 752, C.P. 76000, Santiago de Queretaro, Qro. (Mexico); Aguilar-Arevalo, A A [Instituto de Ciencias Nucleares, Departameto de Fisica de Altas EnergIas, Universidad Nacional Autonoma de Mexico (ICN-UNAM). Apartado Postal 70-543, 04510 Mexico, D. F. (Mexico); D' Olivo, J C [Instituto de Ciencias Nucleares, Departameto de Fisica de Altas EnergIas, Universidad Nacional Autonoma de Mexico (ICN-UNAM). Apartado Postal 70-543, 04510 Mexico, D. F. (Mexico)

    2006-05-15

    We present a semi-analytical derivation of the survival probability of solar neutrinos in the three generation scheme, based on the Magnus approximation of the evolution operator of a three level system, and assuming a mass hierarchy among neutrino mass eigenstates. We have used an exponential profile for the solar electron density in our approximation. The different interesting density regions that appear throughout the propagation are analyzed. Finally, some comments on the allowed regions in the solar neutrino parameter space are addressed.

  7. Neutrino factories

    International Nuclear Information System (INIS)

    Dydak, F.

    2002-01-01

    The discovery of neutrino oscillations marks a major milestone in the history of neutrino physics, and opens a window to what lies beyond the Standard Model. Many current and forthcoming experiments will answer open questions; however, a major step forward, up to and possibly including CP violation in the neutrino mixing matrix, will be offered by the neutrino beams from a neutrino factory. The neutrino factory is a new concept for producing neutrino beams of unprecedented quality in terms of intensity, flavour composition, and precision of the beam parameters. These beams enable the exploration of otherwise inaccessible domains in neutrino oscillation physics by exploiting baselines of planetary dimensions. Suitable detectors pose formidable challenges but seem within reach with only moderate extrapolations from existing technologies. Although the main physics attraction of the neutrino factory is in the area of neutrino oscillations, an interesting spectrum of further opportunities ranging from high-precision, high-rate neutrino scattering to physics with high-intensity stopped muons comes with it

  8. On Analytic Solution of resonant Mixing for Solar Neutrino Oscillations

    OpenAIRE

    Masatoshi, ITO; Takao, KANEKO; Masami, NAKAGAWA; Department of Physics, Meijo University; Department of Physics, Meijo University; Department of Physics, Meijo University

    1988-01-01

    Behavior of resonant mixing in matter-enhancing region for solar neutrino oscillation, the Mikheyev-Smirnov-Wolfenstein mechanism, is reanalyzed by means of an analytic treatment recently proposed. We give solutions in terms of confluent hypergeometric functions, which agree with "exact" solutions of coupled differential equations.

  9. Particle Identification in the T2K TPCs and study of the electron neutrino component in the T2K neutrino beam

    International Nuclear Information System (INIS)

    Giganti, Claudio

    2010-01-01

    This thesis describes the work done on the TPCs of the Near Detector of the T2K experiment. T2K is an experiment installed in Japan and its main purpose is the measurement of the last angle of the neutrino mixing matrix, Θ 13 . The other two angles of the matrix have already been measured in the last years, through the phenomenon of the neutrino oscillations, showing that the neutrinos have masses different from zero. The measurement of the missing angle Θ 13 is of fundamental importance for the neutrino physics as, if this angle is different from zero, CP violation in the lepton sector can occur. Up to now only upper limits on the value of Θ 13 exist: the aim of T2K is to measure this angle or to put upper limits on it with a sensitivity 20 times better than the current limit. This measurement will be done measuring the appearance at the far detector, SuperKamiokande, of electron neutrinos in the muon neutrino beam produced at JPARC. The main background to the measurement of Θ 13 is the electron neutrinos produced together with the muon neutrinos in the beam: this component, expected to be of the order of 1% of the total neutrino flux, has to be measured at the T2K Near Detector, before the oscillations. This can be done selecting neutrino interactions in the Near Detector tracker and using the TPC particle identification capabilities to distinguish electrons from muons. This allows to select a sample of electron neutrino interactions and to measure their spectrum at the Near Detector. During this thesis I have developed the methods to perform the particle identification in the TPCs: the method is based on the measurement of the truncated mean of the energy deposited by the charged particles in the gas: at the typical energy of the T2K neutrinos the difference in the deposited energy between muons and electrons is of the order of 40% and for this reason a resolution better than 10% is needed to distinguish the two particles: as we will show in the thesis, with

  10. GPS survey in long baseline neutrino-oscillation measurement

    CERN Document Server

    Noumi, H; Inagaki, T; Hasegawa, T; Katoh, Y; Kohama, M; Kurodai, M; Kusano, E; Maruyama, T; Minakawa, M; Nakamura, K; Nishikawa, K; Sakuda, M; Suzuki, Y; Takasaki, M; Tanaka, K H; Yamanoi, Y; 10.1109/TNS.2004.836042

    2004-01-01

    We made a series of surveys to obtain neutrino beam line direction toward SuperKamiokande (SK) at a distance of 250 km for the long- baseline neutrino oscillation experiment at KEK. We found that the beam line is directed to SK within 0.03 mr and 0.09 mr (in sigma) in the horizontal and vertical directions, respectively. During beam operation, we monitored the muon distribution from secondary pions produced at the target and collected by a magnetic horn system. We found that the horn system functions like a lens of a point-to- parallel optics with magnification of approximately -100 and the focal length of 2.3 m. Namely, a small displacement of the primary beam position at the target is magnified about a factor -100 at the muon centroid, while the centroid position is almost stable against a change of the incident angle of the primary beam. Therefore, the muon centroid can be a useful monitor of the neutrino beam direction. We could determine the muon centroid within 6 mm and 12 mm in horizontal and vertical ...

  11. Search for GeV-Scale Sterile Neutrinos Responsible for Active Neutrino Oscillations and Baryon Asymmetry of the Universe

    Directory of Open Access Journals (Sweden)

    S. N. Gninenko

    2012-01-01

    Full Text Available Standard Model fails to explain neutrino oscillations, dark matter, and baryon asymmetry of the Universe. All these problems can be solved with three sterile neutrinos added to SM. Quite remarkably, if sterile neutrino masses are well below the electroweak scale, this modification—Neutrino Minimal Standard Model (νMSM—can be tested experimentally. We discuss a new experiment on search for decays of GeV-scale sterile neutrinos, which are responsible for the matter-antimatter asymmetry generation and for the active neutrino masses. If lighter than 2 GeV, these particles can be produced in decays of charm mesons generated by high energy protons in a target, and subsequently decay into SM particles. To fully explore this sector of νMSM, the new experiment requires data obtained with at least 1020 incident protons on target (achievable at CERN SPS in future and a big volume detector constructed from a large amount of identical single modules, with a total sterile neutrino decay length of few kilometers. The preliminary feasibility study for the proposed experiment shows that it has sensitivity which may either lead to the discovery of new particles below the Fermi scale—right-handed partners of neutrinos—or rule out seesaw sterile neutrinos with masses below 2 GeV.

  12. Neutrino mass and oscillation angle phenomena within the asymmetric left-right models

    International Nuclear Information System (INIS)

    Boyarkin, O.; Rein, D.

    1994-07-01

    The light and heavy Majorana neutrinos which appear naturally in SU(2) L x SU(2) R x U(1) B-L model are investigated. The exact solutions are presented for the system of two neutrinos with multipole moments propagating through magnetic and matter fields. The cross section of the reaction e - e - → W - k W - n calculated and its dependence on the mass of the right-handed neutrino and the oscillation angle is investigated. The process e + e - → W + k W - n is also included in our analysis. (author). 26 refs, 9 figs

  13. Neutrinos and Einstein

    CERN Document Server

    Suzuki, Yoichiro

    2005-01-01

    A tiny neutrino mass is a clue to the physics beyond the standard model of elementary particle physics. The primary cosmic rays, mostly protons, are created and accelerated to the relativistic energy in supernova remnants. They traverse the universe and reach the earth. The incoming primary cosmic rays interact with the earth's atmosphere to produce secondary particles, which subsequently decay into neutrinos, called atmospheric neutrinos. The atmospheric neutrinos have shown the evidence of the finite neutrino masses through the phenomena called neutrino oscillations. Neutrinos are detected by large detectors underground like, for example, Super-Kamiokande, SNO and KamLAND. Those detectors use large photomultiplier tubes, which make use of the photo-electric effect to convert photons created by the interaction of neutrinos to electrons to form electric pulses. Neutrinos are therefore created and detected by "Einstein" and have step forward beyond the current physics. Neutrinos may also carry a hit to the ori...

  14. Neutrino sunshine

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    deficit is taken very seriously, and has led to ideas of neutrino oscillations, and oscillation resonances. If the different neutrino varieties - electron, muon and tau - have a mass, then they can oscillate between themselves. A neutrino beam starting off as pure muon-type, for example, would change its composition as it went along. Setting limits on this behaviour is an important objective in neutrino experiments, with 'long baseline' studies - beams covering a long distance between source and detector, playing a vital role. Lincoln Wolfenstein, one of the architects of the new neutrino oscillation scenarios, says 'it is still not clear whether neutrinos have masses or not'. Laboratory experiments try to measure these masses, but so far only upper Unfits have been established. These studies are beginning to reach the limit of their sensitivity and are unlikely to improve drastically. 'But there is indirect evidence,' says Wolfenstein, 'that neutrinos are much lighter.' The solar neutrino problem is really to solar neutrino opportunity,' he continues. Future experiments with gallium and other new neutrino detection techniques, coupled with new high energy neutrino studies, will answer the question

  15. Observation of Muon Neutrino Charged Current Events in an Off-Axis Horn-Focused Neutrino Beam Using the NOvA Prototype Detector

    Energy Technology Data Exchange (ETDEWEB)

    Diaz, Enrique Arrieta [Michigan State Univ., East Lansing, MI (United States)

    2014-01-01

    The NOνA is a long base-line neutrino oscillation experiment. It will study the oscillations between muon and electron neutrinos through the Earth. NOνA consists of two detectors separated by 810 km. Each detector will measure the electron neutrino content of the neutrino (NuMI) beam. Differences between the measurements will reveal details about the oscillation channel. The NOνA collaboration built a prototype detector on the surface at Fermilab in order to develop calibration, simulation, and reconstruction tools, using real data. This 220 ton detector is 110 mrad off the NuMI beam axis. This off-axis location allows the observation of neutrino interactions with energies around 2 GeV, where neutrinos come predominantly from charged kaon decays. During the period between October 2011 and April 2012, the prototype detector collected neutrino data from 1.67 × 1020 protons on target delivered by the NuMI beam. This analysis selected a number of candidate charged current muon neutrino events from the prototype data, which is 30% lower than predicted by the NOνA Monte Carlo simulation. The analysis suggests that the discrepancy comes from an over estimation of the neutrino flux in the Monte Carlo simulation, and in particular, from neutrinos generated in charged kaon decays. The ratio of measured divided by the simulated flux of muon neutrinos coming from charged kaon decays is: 0.70+0.108 -0.094. The NOνA collaboration may use the findings of this analysis to introduce a more accurate prediction of the neutrino flux produced by the NuMI beam in future Monte Carlo simulations.

  16. nuPRISM: An experimental method to remove neutrino interaction uncertainties from oscillation experiments

    CERN Multimedia

    CERN. Geneva

    2014-01-01

    Future experiments propose to make precision measurements of parameters in the neutrino mixing matrix, including the possibly maximal mixing angle theta23, and an unknown CP violating phase, dCP, by comparing the event rate of neutrinos and antineutrinos observed close to, and far from the source. Such "near to far" extrapolation methods must achieve percent level understanding of neutrino and antineutrino interactions; the interaction determines the relationship between experimental observables and the oscillation probability which depends on the neutrino energy. However, recent developments over the last 5 years demonstrate that our understanding of neutrino interactions is insufficient. In particular, the interaction of neutrinos on correlated pairs of nucleons has only recently been added to neutrino interaction simulations. The identification of these processes as interactions on a single nucleon results in a significant bias to the measured mixing parameters, even when near detector i...

  17. Neutrino Factory

    CERN Document Server

    Bogomilov, M; 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; Mokhov, N; Neuffer, D; Popovic, M; Strait, J; Striganov, S; Morfín, J  G; Wands, R; Snopok, P; Bogacz, 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

    2014-01-01

    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 $\\theta_{13} > 0$. The measured value of $\\theta_{13}$ 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$\

  18. Matter effects in upward-going muons and sterile neutrino oscillations

    CERN Document Server

    Ambrosio, M; Auriemma, G; Bakari, D; Baldini, A; Barbarino, G C; Barish, B C; Battistoni, G; Becherini, Y; Bellotti, R; Bemporad, C; Bernardini, P; Bilokon, H; Bisi, V; Bloise, C; Bower, C; Brigida, M; Bussino, S; Cafagna, F; Calicchio, M; Campana, D; Carboni, M; Caruso, R; Cecchini, S; Cei, F; Chiarella, V; Choudhary, B C; Coutu, S; De Cataldo, G; Dekhissi, H; De Marzo, C; De Mitri, I; Derkaoui, J E; De Vincenzi, M; Di Credico, A; Erriquez, O; Favuzzi, C; Forti, C; Fusco, P; Giacomelli, G; Giannini, G; Giglietto, N; Giorgini, M; Grassi, M; Gray, L; Grillo, A; Guarino, F; Gustavino, C; Habig, A; Hanson, K; Heinz, R; Iarocci, Enzo; Katsavounidis, E; Katsavounidis, I; Kearns, E T; Kim, H; Kyriazopoulou, S; Lammanna, E; Lane, C; Levins, D S; Lipari, P; Longley, N P; Longo, M J; Loparco, F; Maaroufi, F; Mancarella, G; Mandrioli, G; Margiotta, A; Marini, A; Martello, D; Marzari-Chiesa, A; Mazziotta, M N; Michael, D G; Mikheyev, S P; Miller, L; Monacelli, P; Montaruli, T; Monteno, M; Mufson, S L; Musser, J; Nicolò, D; Nolty, R; Orth, C; Osteria, G; Palamara, O; Patera, V; Patrizii, L; Pazzi, R; Peck, C W; Perrone, L; Petrera, S; Pistilli, P; Popa, V; Rainó, A; Reynoldson, J; Ronga, F; Rrhioua, A; Satriano, C; Scapparone, E; Scholberg, K; Sciubba, A; Serra, P; Sioli, M; Sirri, G; Sitta, M; Spinelli, P; Spinetti, M; Spurio, M; Steinberg, R; Stone, J L; Sulak, Lawrence R; Surdo, A; Tarle, G; Togo, V; Vakili, M; Walter, C W; Webb, R

    2001-01-01

    The angular distribution of upward-going muons produced by atmospheric neutrinos in the rock below the MACRO detector shows anomalies in good agreement with two flavor nu /sub mu / to nu /sub tau / oscillations with maximum mixing and Delta m/sup 2/ around 0.0024 eV/sup 2/. Exploiting the dependence of magnitude of the matter effect on the oscillation channel, and using a set of 809 upward-going muons observed in MACRO, we show that the two flavor nu /sub mu / to nu /sub s/ oscillation is disfavored with 99% C.L. with respect to nu /sub mu / to nu /sub tau /. (29 refs).

  19. Search for neutrino oscillations at the palo verde nuclear reactors

    Science.gov (United States)

    Boehm; Busenitz; Cook; Gratta; Henrikson; Kornis; Lawrence; Lee; McKinny; Miller; Novikov; Piepke; Ritchie; Tracy; Vogel; Wang; Wolf

    2000-04-24

    We report on the initial results from a measurement of the antineutrino flux and spectrum at a distance of about 800 m from the three reactors of the Palo Verde Nuclear Generating Station using a segmented gadolinium-loaded scintillation detector. We find that the antineutrino flux agrees with that predicted in the absence of oscillations excluding at 90% C.L. nu;(e)-nu;(x) oscillations with Deltam(2)>1.12x10(-3) eV(2) for maximal mixing and sin (2)2straight theta>0.21 for large Deltam(2). Our results support the conclusion that the atmospheric neutrino oscillations observed by Super-Kamiokande do not involve nu(e).

  20. Updated global 3+1 analysis of short-baseline neutrino oscillations

    Science.gov (United States)

    Gariazzo, S.; Giunti, C.; Laveder, M.; Li, Y. F.

    2017-06-01

    We present the results of an updated fit of short-baseline neutrino oscillation data in the framework of 3+1 active-sterile neutrino mixing. We first consider ν e and {\\overline{ν}}_e disappearance in the light of the Gallium and reactor anomalies. We discuss the implications of the recent measurement of the reactor {\\overline{ν}}_e spectrum in the NEOS experiment, which shifts the allowed regions of the parameter space towards smaller values of | U e4|2. The β-decay constraints of the Mainz and Troitsk experiments allow us to limit the oscillation length between about 2 cm and 7 m at 3 σ for neutrinos with an energy of 1 MeV. The corresponding oscillations can be discovered in a model-independent way in ongoing reactor and source experiments by measuring ν e and {\\overline{ν}}_e disappearance as a function of distance. We then consider the global fit of the data on short-baseline {}_{ν_{μ}}^{(-)}{\\to}_{ν_e}^{(-)} transitions in the light of the LSND anomaly, taking into account the constraints from {}_{ν_e}^{(-)} and {}_{ν_{μ}}^{(-)} disappearance experiments, including the recent data of the MINOS and IceCube experiments. The combination of the NEOS constraints on | U e4|2 and the MINOS and IceCube constraints on | U μ4|2 lead to an unacceptable appearance-disappearance tension which becomes tolerable only in a pragmatic fit which neglects the MiniBooNE low-energy anomaly. The minimization of the global χ 2 in the space of the four mixing parameters Δ m 41 2 , | U e4|2, | U μ4|2, and | U τ4|2 leads to three allowed regions with narrow Δ m 41 2 widths at Δ m 41 2 ≈ 1.7 (best-fit), 1.3 (at 2 σ), 2.4 (at 3 σ) eV2. The effective amplitude of short-baseline {}_{ν_{μ}}^{(-)}{\\to}_{ν_e}^{(-)} oscillations is limited by 0.00048 ≲ sin2 2 ϑ eμ ≲ 0.0020 at 3 σ. The restrictions of the allowed regions of the mixing parameters with respect to our previous global fits are mainly due to the NEOS constraints. We present a comparison of the

  1. New (anti)neutrino results from the T2K experiment on CP violation in the lepton sector

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    T2K is a long-baseline neutrino experiment in which a muon neutrino beam produced by J-PARC in Tokai is sent 295 km across Japan to the Super-Kamiokande detector, to study neutrino oscillations via the disappearance of muon neutrinos and the appearance of electron neutrinos. Since the start of operations in 2010, T2K has conclusively observed muon neutrino to electron neutrino oscillations, opening the door to the observation of CP violation in neutrino mixing, and performed the most precise measurement of the muon neutrino disappearance parameters. In a joint analysis between these two modes, T2K placed its first constraints on the CP-violating phase delta. Starting in 2014, T2K has been running primarily with an antineutrino beam in order to study the corresponding antineutrino oscillations, resulting in leading measurements of the muon antineutrino disappearance parameters. The joint analysis of neutrino and antineutrino data indicates that CP-conserving parameters lie outside the 90% confidence interval....

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

    International Nuclear Information System (INIS)

    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

  3. Solar neutrino observations and neutrino oscillations

    International Nuclear Information System (INIS)

    Kuo, T.K.; Pantaleone, J.

    1990-01-01

    The results of recent Kamiokande-II and 37 Cl solar-neutrino experiments are quantitatively analyzed assuming the Mikheyev-Smirnov-Wolfenstein solution to the solar-neutrino problem. It is found that the parameter region known as the ''large mass'' solution to the solar-neutrino problem is disfavored by a little more than 1 σ while the ''small mass'' and ''large angle'' solutions are in good agreement at this level. The implications on this analysis from time variations in the data are discussed

  4. Study of the wave packet treatment of neutrino oscillation at Daya Bay

    Science.gov (United States)

    Daya Bay Collaboration

    2017-09-01

    The disappearance of reactor \\bar{ν }_e observed by the Daya Bay experiment is examined in the framework of a model in which the neutrino is described by a wave packet with a relative intrinsic momentum dispersion σ _{rel}. Three pairs of nuclear reactors and eight antineutrino detectors, each with good energy resolution, distributed among three experimental halls, supply a high-statistics sample of \\bar{ν }_e acquired at nine different baselines. This provides a unique platform to test the effects which arise from the wave packet treatment of neutrino oscillation. The modified survival probability formula was used to fit Daya Bay data, providing the first experimental limits: 2.38 × 10^{-17}< σ _{rel} < 0.23. Treating the dimensions of the reactor cores and detectors as constraints, the limits are improved: 10^{-14} ≲ σ _ {rel} < 0.23, and an upper limit of σ _ {rel}<0.20 (which corresponds to σ _x ≳ 10^{-11} {cm }) is obtained. All limits correspond to a 95% C.L. Furthermore, the effect due to the wave packet nature of neutrino oscillation is found to be insignificant for reactor antineutrinos detected by the Daya Bay experiment thus ensuring an unbiased measurement of the oscillation parameters sin ^22θ _{13} and Δ m^2_{32} within the plane wave model.

  5. Tests of Lorentz and CPT violation with MiniBooNE neutrino oscillation excesses

    International Nuclear Information System (INIS)

    Katori, Teppei

    2014-01-01

    Lorentz and CPT symmetry violaton is a predicted phenomenon of Planck–scale physics. Various types of data are analyzed to search for Lorentz violation under the Standard–Model Extension (SME) framework, including neutrino oscillation data. MiniBooNE is a short–baseline neutrino oscillation experiment at Fermilab. The measured excesses from MiniBooNE cannot be reconciled within the neutrino Standard Model (vSM); thus it might be a signal of new physics, such as Lorentz violation. We have analyzed the sidereal time dependence of MiniBooNE data for signals of the possible sidereal time dependence of the ocillation signals. we find that the v e appearance data prefer a sidereal time–independent solution, and the v-bar e appearance data slightly prefer a sidereal time–dependent solution, however, the statistical significance is not high to claim the discovery. Limits of order 10 −20 GeV are placed on combinations of SME coefficients

  6. Non-cyclic phases for neutrino oscillations in quantum field theory

    International Nuclear Information System (INIS)

    Blasone, Massimo; Capolupo, Antonio; Celeghini, Enrico; Vitiello, Giuseppe

    2009-01-01

    We show the presence of non-cyclic phases for oscillating neutrinos in the context of quantum field theory. Such phases carry information about the non-perturbative vacuum structure associated with the field mixing. By subtracting the condensate contribution of the flavor vacuum, the previously studied quantum mechanics geometric phase is recovered.

  7. Is the neutrino as changeable as a weather vane?

    CERN Multimedia

    2003-01-01

    We conclude the first part of our feature on the CNGS project with a sneak preview of next week's articles. The neutrino is something of a headache for physicists, who have come to wonder whether the muon neutrino is capable of changing into a tau neutrino. This hypothesis would explain the deficit of muon neutrinos in the atmosphere. When cosmic rays interact with the nuclei of atoms from the upper atmosphere, two kinds of neutrino are produced: muon neutrinos and electron neutrinos. Measurements have shown that there are fewer muon neutrinos than would normally have been expected. In 1998, the Super Kamiokande experiment in Japan revealed that the oscillation (or transformation) of muon neutrinos into tau neutrinos could be responsible for this shortfall, an idea which was supported, shortly afterwards, by the K2K (KEK to Kamioka) experiment. The main purpose of the experiments at the CNGS (CERN Neutrinos to Gran Sasso) project is to demonstrate this oscillation, which is thought to occur over long distan...

  8. THE POTENTIAL FOR NEUTRINO PHYSICS AT MUON COLLIDERS AND DEDICATED HIGH CURRENT MUON STORAGE RINGS

    International Nuclear Information System (INIS)

    BIGI, I.; BOLTON, T.; FORMAGGIO, J.; HARRIS, D.; MORFIN, J.; SPENTZOURIS, P.; YU, J.; KAYSER, B.; KING, B.J.; MCFARLAND, K.; PETROV, A.; SCHELLMAN, H.; VELASCO, M.; SHROCK, R.

    2000-01-01

    Conceptual design studies are underway for both muon colliders and high-current non-colliding muon storage rings that have the potential to become the first true neutrino factories. Muon decays in long straight sections of the storage rings would produce uniquely intense and precisely characterized two-component neutrino beams--muon neutrinos plus electron antineutrinos from negative muon decays and electron neutrinos plus muon antineutrinos from positive muons. This article presents a long-term overview of the prospects for these facilities to greatly extend the capabilities for accelerator-based neutrino physics studies for both high rate and long baseline neutrino experiments. As the first major physics topic, recent experimental results involving neutrino oscillations have motivated a vigorous design effort towards dedicated neutrino factories that would store muon beams of energies 50 GeV or below. These facilities hold the promise of neutrino oscillation experiments with baselines up to intercontinental distances and utilizing well understood beams that contain, for the first time, a substantial component of multi-GeV electron-flavored neutrinos. In deference to the active and fast-moving nature of neutrino oscillation studies, the discussion of long baseline physics at neutrino factories has been limited to a concise general overview of the relevant theory, detector technologies, beam properties, experimental goals and potential physics capabilities. The remainder of the article is devoted to the complementary high rate neutrino experiments that would study neutrino-nucleon and neutrino-electron scattering and would be performed at high performance detectors placed as close as is practical to the neutrino production straight section of muon storage rings in order to exploit beams with transverse dimensions as small as a few tens of centimeters

  9. THE POTENTIAL FOR NEUTRINO PHYSICS AT MUON COLLIDERS AND DEDICATED HIGH CURRENT MUON STORAGE RINGS

    Energy Technology Data Exchange (ETDEWEB)

    BIGI,I.; BOLTON,T.; FORMAGGIO,J.; HARRIS,D.; MORFIN,J.; SPENTZOURIS,P.; YU,J.; KAYSER,B.; KING,B.J.; MCFARLAND,K.; PETROV,A.; SCHELLMAN,H.; VELASCO,M.; SHROCK,R.

    2000-05-11

    Conceptual design studies are underway for both muon colliders and high-current non-colliding muon storage rings that have the potential to become the first true neutrino factories. Muon decays in long straight sections of the storage rings would produce uniquely intense and precisely characterized two-component neutrino beams--muon neutrinos plus electron antineutrinos from negative muon decays and electron neutrinos plus muon antineutrinos from positive muons. This article presents a long-term overview of the prospects for these facilities to greatly extend the capabilities for accelerator-based neutrino physics studies for both high rate and long baseline neutrino experiments. As the first major physics topic, recent experimental results involving neutrino oscillations have motivated a vigorous design effort towards dedicated neutrino factories that would store muon beams of energies 50 GeV or below. These facilities hold the promise of neutrino oscillation experiments with baselines up to intercontinental distances and utilizing well understood beams that contain, for the first time, a substantial component of multi-GeV electron-flavored neutrinos. In deference to the active and fast-moving nature of neutrino oscillation studies, the discussion of long baseline physics at neutrino factories has been limited to a concise general overview of the relevant theory, detector technologies, beam properties, experimental goals and potential physics capabilities. The remainder of the article is devoted to the complementary high rate neutrino experiments that would study neutrino-nucleon and neutrino-electron scattering and would be performed at high performance detectors placed as close as is practical to the neutrino production straight section of muon storage rings in order to exploit beams with transverse dimensions as small as a few tens of centimeters.

  10. Sudbury neutrino observatory proposal

    International Nuclear Information System (INIS)

    Ewan, G.T.; Evans, H.C.; Lee, H.W.

    1987-10-01

    This report is a proposal by the Sudbury Neutrino Observatory (SNO) collaboration to develop a world class laboratory for neutrino astrophysics. This observatory would contain a large volume heavy water detector which would have the potential to measure both the electron-neutrino flux from the sun and the total solar neutrino flux independent of neutrino type. It will therefore be possible to test models of solar energy generation and, independently, to search for neutrino oscillations with a sensitivity many orders of magnitude greater than that of terrestrial experiments. It will also be possible to search for spectral distortion produced by neutrino oscillations in the dense matter of the sun. Finally the proposed detector would be sensitive to neutrinos from a stellar collapse and would detect neutrinos of all types thus providing detailed information on the masses of muon- and tau-neutrinos. The neutrino detector would contain 1000 tons of D20 and would be located more than 2000 m below ground in the Creighton mine near Sudbury. The operation and performance of the proposed detector are described and the laboratory design is presented. Construction schedules and responsibilities and the planned program of technical studies by the SNO collaboration are outlined. Finally, the total capital cost is estimated to be $35M Canadian and the annual operating cost, after construction, would be $1.8 M Canadian, including the insurance costs of the heavy water

  11. Neutrino physics

    International Nuclear Information System (INIS)

    Gil-Botella, I.

    2011-01-01

    The fundamental properties of neutrinos are reviewed in these lectures. The first part is focused on the basic characteristics of neutrinos in the Standard Model and how neutrinos are detected. Neutrino masses and oscillations are introduced and a summary of the most important experimental results on neutrino oscillations to date is provided. Then, present and future experimental proposals are discussed, including new precision reactor and accelerator experiments. Finally, different approaches for measuring the neutrino mass and the nature (Majorana or Dirac), of neutrinos are reviewed. The detection of neutrinos from supernovae explosions and the information that this measurement can provide are also summarized at the end. (author)

  12. A large liquid scintillator detector for a long baseline neutrino oscillation experiment

    International Nuclear Information System (INIS)

    Border, P.; Cushman, P.; Heller, K.; Maxam, D.; Nelson, J.K.; Ruddick, K.; Rusack, R.; Schwienhorst, R.; Berg, T.; Chase, T.; Hansen, M.; Bower, C.; Hatcher, R.; Heinz, R.; Miller, L.; Mufson, S.

    2001-01-01

    We present the concept and design of a liquid scintillator detector for a long-baseline neutrino oscillation experiment. Neutrinos interact in 2.5 cm thick steel plates alternating with 2.0 cm thick planes of liquid scintillator. The scintillator is contained in multicell PVC extrusions containing individual 2 cmx3 cm cells up to 8 m long. Readout of the scintillation light is via wavelength-shifting fibers which transport light to pixellated photodetectors at one end of the cells

  13. Lifting degeneracies in the oscillation parameters by a neutrino factory

    International Nuclear Information System (INIS)

    Aoki, Mayumi; Hagiwara, Kaoru; Okamura, Naotoshi

    2005-01-01

    We study the potential of a very long baseline neutrino oscillation experiment with a neutrino factory and a large segmented water-Cerenkov calorimeter detector in resolving the degeneracies in the neutrino oscillation parameters; the sign of the larger mass-squared difference δm 13 2 , the sign of vertical bar U μ3 vertical bar 2 (=sin 2 θ ATM )-1/2, and a possible two-fold ambiguity in the determination of the CP phase δ MNS . We find that the above problems can be resolved even if the particle charges are not measured. The following results are obtained in our exploratory study for a neutrino factory which delivers 10 21 decaying μ + and μ - at 10 GeV and a 100 kton detector which is placed 2100 km away and is capable of measuring the event energy and distinguishing e + /- from μ + /-, but not their charges. The sign of δm 13 2 can be determined for 4 vertical bar U e3 vertical bar 2 (1- vertical bar U e3 vertical bar 2 )=sin 2 2θ RCT -bar 0.008. That of sin 2 θ ATM -1/2 can be resolved for sin 2 2θ ATM =0.96 when sin 2 2θ RCT -bar 0.06. The CP-violating phase δ MNS can be uniquely constrained for sin 2 2θ RCT -bar 0.02 if its true value is around 90 o or 270 o , while it can be constrained for sin 2 2θ RCT -bar 0.03 if its true value is around 0 deg. or 180 deg

  14. A review of matter oscillations and solar neutrinos

    International Nuclear Information System (INIS)

    Rosen, S.P.

    1986-01-01

    We review the theory of the Mikheyev-Smirnov-Wolfenstein effect, and examine its consequences for the solar neutrino problem. Using a two-flavor model, we discuss the solutions in the Δ 2 -sin 2 2Θ parameter space for the 37 Cl experiment, and describe their predictions for the 71 Ga experiment and for the spectrum of electron-neutrinos arriving at earth. 18 refs

  15. Neutrinos today

    International Nuclear Information System (INIS)

    Pontecorvo, B.; Bilen'kij, S.

    1987-01-01

    After the famous 1983 discovery of intermediate W, Z 0 bosons it may be stated with certainty that W, Z 0 are entirely responsible for the production of neutrinos and for their interactions. Neutrino physics notions are presented from this point of view in the first four introductory, quite elementary, paragraphs of the paper. The following seven paragraphs are more sophisticated. They are devoted to the neutrino mass and neutrino mixing question, which is the most actual problem in today neutrino physics. Vacuum neutrino oscillations, matter neutrino oscillations and netrinoless double-decay are considered. Solar neutrino physics is discussed in some detail from the point of view of vacuum and matter neutrino oscillations. The role played by neutrinos in the Universe is briefly considered. In the last paragraph there discussed the probable observation by different groups of neutrinos connected with the Supernova 1987 A: the first observation of gravitational star collapse (at least the general rehearsal of such observation) opens up a new era in astronomy of today exerimental physics and astrophysics is presented at the end of the paper in the form of a Table

  16. Treatment of solar neutrino-oscillations in solar matter. The MSW effect

    International Nuclear Information System (INIS)

    Messiah, A.

    1986-01-01

    Mikheyev and Smirnov, following Wolfenstein's theory of neutrino oscillations in the presence of matter, have found that the change of flavour of solar neutrinos may be spectacularly enhanced in the presence of solar matter, when the parameters of the neutrino mass operator fall in a suitable range (MSW effect). It is shown that this effect can be readily deduced from the adiatic solution of the equation of flavour evolution. A complete study of the two-flavour case is given, permitting to calculate, for any set of values of the mass operator parameters, the ν e suppression factor at the site of detection on earth. The adiabatic approximation holds over a wide range of the parameters, leading to especially simple expressions. Our calculations cover the whole range, including domains where the adiabatic approximation is no longer valid. Some of the results, presented in a form most suited for an analysis of solar neutrino experiments, are displayed for illustration and discussed. 7 refs

  17. Sterile Neutrino Search with MINOS

    International Nuclear Information System (INIS)

    Devan, Alena V.

    2015-01-01

    MINOS, Main Injector Neutrino Oscillation Search, is a long-baseline neutrino oscillation experiment in the NuMI muon neutrino beam at the Fermi National Accelerator Laboratory in Batavia, IL. It consists of two detectors, a near detector positioned 1 km from the source of the beam and a far detector 734 km away in Minnesota. MINOS is primarily designed to observe muon neutrino disappearance resulting from three flavor oscillations. The Standard Model of Particle Physics predicts that neutrinos oscillate between three active flavors as they propagate through space. This means that a muon-type neutrino has a certain probability to later interact as a different type of neutrino. In the standard picture, the neutrino oscillation probabilities depend only on three neutrino flavors and two mass splittings, Δm 2 . An anomaly was observed by the LSND and MiniBooNE experiments that suggests the existence of a fourth, sterile neutrino flavor that does not interact through any of the known Standard Model interactions. Oscillations into a theoretical sterile flavor may be observed by a deficit in neutral current interactions in the MINOS detectors. A distortion in the charged current energy spectrum might also be visible if oscillations into the sterile flavor are driven by a large mass-squared difference, Δm s 2 ~ 1 eV 2 . The results of the 2013 sterile neutrino search are presented here.

  18. Neutrino physics

    CERN Document Server

    Hernandez, P.

    2016-01-01

    This is the writeup of the lectures on neutrino physics delivered at various schools: TASI and Trieste in 2013 and the CERN-Latin American School in 2015. The topics discussed in this lecture include: general properties of neutrinos in the SM, the theory of neutrino masses and mixings (Dirac and Majorana), neutrino oscillations both in vacuum and in matter, as well as an overview of the experimental evidence for neutrino masses and of the prospects in neutrino oscillation physics. We also briefly review the relevance of neutri- nos in leptogenesis and in beyond-the-Standard-Model physics.

  19. Solar neutrino oscillation parameters after SNO Phase-III and SAGE Part-III

    International Nuclear Information System (INIS)

    Yang Ping; Liu Qiuyu

    2009-01-01

    We analyse the recently published results from solar neutrino experiments SNO Phase-III and SAGE Part-III and show their constraints on solar neutrino oscillation parameters, especially for the mixing angle θ 12 . Through a global analysis using all existing data from SK, SNO, Ga and Cl radiochemical experiments and long base line reactor experiment KamLAND , we obtain the parameters Δm 12 2 =7.684 -0.208 +0.212 x 10 -5 eV 2 , tan 2 θ 12 =0.440 -0.057 +0.059 . We also find that the discrepancy between the KamLAND and solar neutrino results can be reduced by choosing a small non-zero value for the mixing angle θ 13 . (authors)

  20. Search for neutrino oscillations in the MINOS experiment by using quasi-elastic interactions

    Energy Technology Data Exchange (ETDEWEB)

    Piteira, Rodolphe [Univ. Pierre et Marie Curie, Paris (France)

    2005-09-29

    The enthusiasm of the scientific community for studying oscillations of neutrinos is equaled only by the mass of their detectors. The MINOS experiment determines and compares the near spectrum of muonic neutrinos from the NUMI beam to the far one, in order to measure two oscillation parameters: Δm$2\\atop{23}$ and sin2 (2θ23). The spectra are obtained by analyzing the charged current interactions which difficulty lies in identifying the interactions products (e.g. muons). An alternative method identifying the traces of muons, bent by the magnetic field of the detectors, and determining their energies is presented in this manuscript. The sensitivity of the detectors is optimal for the quasi-elastic interactions, for which a selection method is proposed, to study their oscillation. Even though it reduces the statistics, such a study introduces fewer systematic errors, constituting the ideal method on the long range.

  1. Experimental neutrino physics

    CERN Document Server

    Link, Jonathan M

    2018-01-01

    Neutrinos have a smaller mass than any other known particle and are the subject of intense recent studies, as well as this book. The author provides a coherent introduction to the necessary theoretical background and experimental methods used by modern neutrino physicists. It’s designed as a one-stop reference addressing what is currently known about the neutrino hypothesis, discovery of the neutrino, theory of weak interactions, solar neutrino puzzle, and neutrino oscillation. It then gives a detailed account of practical approaches for study of precision oscillations, neutrino mass and other neutrino properties, sterile neutrinos, and neutrino messengers from space and Earth’s interior.

  2. Study of the wave packet treatment of neutrino oscillation at Daya Bay

    Energy Technology Data Exchange (ETDEWEB)

    An, F.P. [East China Univ. of Science and Technology, Shanghai (China). Inst. of Modern Physics; Balantekin, A.B. [Wisconsin Univ., Madison, WI (United States); Band, H.R. [Yale Univ., New Haven, CT (United States). Dept. of Physics; Collaboration: Daya Bay Collaboration; and others

    2017-09-15

    The disappearance of reactor anti ν{sub e} observed by the Daya Bay experiment is examined in the framework of a model in which the neutrino is described by a wave packet with a relative intrinsic momentum dispersion σ{sub rel}. Three pairs of nuclear reactors and eight antineutrino detectors, each with good energy resolution, distributed among three experimental halls, supply a high-statistics sample of anti ν{sub e} acquired at nine different baselines. This provides a unique platform to test the effects which arise from the wave packet treatment of neutrino oscillation. The modified survival probability formula was used to fit Daya Bay data, providing the first experimental limits: 2.38 x 10{sup -17} < σ{sub rel} < 0.23. Treating the dimensions of the reactor cores and detectors as constraints, the limits are improved: 10{sup -14} or similar 10{sup -11} cm) is obtained. All limits correspond to a 95% C.L. Furthermore, the effect due to the wave packet nature of neutrino oscillation is found to be insignificant for reactor antineutrinos detected by the Daya Bay experiment thus ensuring an unbiased measurement of the oscillation parameters sin{sup 2}2θ{sub 13} and Δm{sup 2}{sub 32} within the plane wave model. (orig.)

  3. Neutrino-electron scattering and the choice between different MSW solutions of the solar neutrino problem

    International Nuclear Information System (INIS)

    Rosen, S.P.; Gelb, J.M.

    1987-01-01

    We consider the scattering of solar neutrinos by electrons as a means for distinguishing between MSW solutions of the solar neutrino problem. In terms of the ratio R between the observed cross-section and that for pure electron-type neutrinos, we find that some correlation between the value R and the appropriate solution. 9 refs., 3 figs

  4. Search for “anomalies” from neutrino and anti-neutrino oscillations at $\\Delta_m^{2} ≈ 1eV^{2}$ with muon spectrometers and large LAr–TPC imaging detectors

    CERN Document Server

    Antonello, M; Baibussinov, B; Bilokon, H; Boffelli, F; Bonesini, M; Calligarich, E; Canci, N; Centro, S; Cesana, A; Cieslik, K; Cline, D B; Cocco, A G; Dequal, D; Dermenev, A; Dolfini, R; De Gerone, M; Dussoni, S; Farnese, C; Fava, A; Ferrari, A; Fiorillo, G; Garvey, G T; Gatti, F; Gibin, D; Gninenko, S; Guber, F; Guglielmi, A; Haranczyk, M; Holeczek, J; Ivashkin, A; Kirsanov, M; Kisiel, J; Kochanek, I; Kurepin, A; Łagoda, J; Lucchini, G; Louis, W C; Mania, S; Mannocchi, G; Marchini, S; Matveev, V; Menegolli, A; Meng, G; Mills, G B; Montanari, C; Nicoletto, M; Otwinowski, S; Palczewski, T J; Passardi, G; Perfetto, F; Picchi, P; Pietropaolo, F; Płonski, P; Rappoldi, A; Raselli, G L; Rossella, M; Rubbia, C; Sala, P; Scaramelli, A; Segreto, E; Stefan, D; Stepaniak, J; Sulej, R; Suvorova, O; Terrani, M; Tlisov, D; Van de Water, R G; Trinchero, G; Turcato, M; Varanini, F; Ventura, S; Vignoli, C; Wang, H G; Yang, X; Zani, A; Zaremba, K; Benettoni, M; Bernardini, P; Bertolin, A; Bozza, C; Brugnera, R; Cecchetti, A; Cecchini, S; Collazuol, G; Creti, P; Dal Corso, F; De Mitri, I; De Robertis, G; De Serio, M; Degli Esposti, L; Di Ferdinando, D; Dore, U; Dusini, S; Fabbricatore, P; Fanin, C; Fini, R A; Fiore, G; Garfagnini, A; Giacomelli, G; Giacomelli, R; Grella, G; Guandalini, C; Guerzoni, M; Kose, U; Laurenti, G; Laveder, M; Lippi, I; Loddo, F; Longhin, A; Loverre, P; Mancarella, G; Mandrioli, G; Margiotta, A; Marsella, G; Mauri, N; Medinaceli, E; Mengucci, A; Mezzetto, M; Michinelli, R; Muciaccia, M T; Orecchini, D; Paoloni, A; Pastore, A; Patrizii, L; Pozzato, M; Rescigno, R; Rosa, G; Simone, S; Sioli, M; Sirri, G; Spurio, M; Stanco, L; Stellacci, S; Surdo, A; Tenti, M; Togo, V; Ventura, M; Zago, M

    2012-01-01

    This proposal describes an experimental search for sterile neutrinos beyond the Standard Model with a new CERN-SPS neutrino beam. The experiment is based on two identical LAr-TPC's followed by magnetized spectrometers, observing the electron and muon neutrino events at 1600 and 300 m from the proton target. This project will exploit the ICARUS T600, moved from LNGS to the CERN "Far" position. An additional 1/4 of the T600 detector will be constructed and located in the "Near" position. Two spectrometers will be placed downstream of the two LAr-TPC detectors to greatly complement the physics capabilities. Spectrometers will exploit a classical dipole magnetic field with iron slabs, and a new concept air-magnet, to perform charge identification and muon momentum measurements in a wide energy range over a large transverse area. In the two positions, the radial and energy spectra of the nu_e beam are practically identical. Comparing the two detectors, in absence of oscillations, all cross sections and experimenta...

  5. Exact series solution to the two flavor neutrino oscillation problem in matter

    International Nuclear Information System (INIS)

    Blennow, Mattias; Ohlsson, Tommy

    2004-01-01

    In this paper, we present a real nonlinear differential equation for the two flavor neutrino oscillation problem in matter with an arbitrary density profile. We also present an exact series solution to this nonlinear differential equation. In addition, we investigate numerically the convergence of this solution for different matter density profiles such as constant and linear profiles as well as the Preliminary Reference Earth Model describing the Earth's matter density profile. Finally, we discuss other methods used for solving the neutrino flavor evolution problem

  6. Neutrino mass, a status report

    International Nuclear Information System (INIS)

    Robertson, R.G.H.

    1993-01-01

    Experimental approaches to neutrino mass include kinematic mass measurements, neutrino oscillation searches at rectors and accelerators, solar neutrinos, atmospheric neutrinos, and single and double beta decay. The solar neutrino results yield fairly strong and consistent indications that neutrino oscillations are occurring. Other evidence for new physics is less consistent and convincing

  7. Sterile Neutrino Search with MINOS

    Energy Technology Data Exchange (ETDEWEB)

    Devan, Alena V. [College of William and Mary, Williamsburg, VA (United States)

    2015-08-01

    MINOS, Main Injector Neutrino Oscillation Search, is a long-baseline neutrino oscillation experiment in the NuMI muon neutrino beam at the Fermi National Accelerator Laboratory in Batavia, IL. It consists of two detectors, a near detector positioned 1 km from the source of the beam and a far detector 734 km away in Minnesota. MINOS is primarily designed to observe muon neutrino disappearance resulting from three flavor oscillations. The Standard Model of Particle Physics predicts that neutrinos oscillate between three active flavors as they propagate through space. This means that a muon-type neutrino has a certain probability to later interact as a different type of neutrino. In the standard picture, the neutrino oscillation probabilities depend only on three neutrino flavors and two mass splittings, Δm2. An anomaly was observed by the LSND and MiniBooNE experiments that suggests the existence of a fourth, sterile neutrino flavor that does not interact through any of the known Standard Model interactions. Oscillations into a theoretical sterile flavor may be observed by a deficit in neutral current interactions in the MINOS detectors. A distortion in the charged current energy spectrum might also be visible if oscillations into the sterile flavor are driven by a large mass-squared difference, ms2 ~ 1 eV2. The results of the 2013 sterile neutrino search are presented here.

  8. Short-baseline electron antineutrino disappearance study by using neutrino sources from {sup 13}C + {sup 9}Be reaction

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Jae Won; Cheoun, Myung-Ki [Department of Physics and Origin of Matter and Evolution of Galaxies (OMEG) Institute, Soongsil University, Seoul 156-743 (Korea, Republic of); Kajino, Toshitaka [Division of Theoretical Astronomy, National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588 (Japan); Hayakawa, Takehito, E-mail: shine8199@skku.edu, E-mail: cheoun@ssu.ac.kr, E-mail: kajino@nao.ac.jp, E-mail: hayakawa.takehito@qst.go.jp [Quantum Beam Science Directorate (QUBS), Japan Atomic Energy Agency (JAEA), 2-4 Shirane, Shirakata, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan)

    2017-04-01

    To investigate the existence of sterile neutrino, we propose a new neutrino production method using {sup 13}C beams and a {sup 9}Be target for short-baseline electron antineutrino (ν-bar {sub e} ) disappearance study. The production of secondary unstable isotopes which can emit neutrinos from the {sup 13}C + {sup 9}Be reaction is calculated with three different nucleus-nucleus (AA) reaction models. Different isotope yields are obtained using these models, but the results of the neutrino flux are found to have unanimous similarities. This feature gives an opportunity to study neutrino oscillation through shape analysis. In this work, expected neutrino flux and event rates are discussed in detail through intensive simulation of the light ion collision reaction and the neutrino flux from the beta decay of unstable isotopes followed by this collision. Together with the reactor and accelerator anomalies, the present proposed ν-bar {sub e} source is shown to be a practically alternative test of the existence of the Δ m {sup 2} ∼ 1 eV{sup 2} scale sterile neutrino.

  9. Neutrino oscillation in the matter, in the context of tree families

    International Nuclear Information System (INIS)

    Bellandi, J.; Guzzo, M.M.

    1994-01-01

    From the equation of time evolution of three neutrino families system, in presence of matter, an analytical solution is derived for probability amplitude of transition between flavors. Particular cases, mixing between two families at constant matter density, and oscillations between three families in the vacuum, are obtained from the general solution

  10. Search for sterile neutrinos at a new short-baseline CERN neutrino beam

    International Nuclear Information System (INIS)

    Mauri, N.

    2014-01-01

    In the last few years the experimental results on neutrino/anti-neutrino oscillations at Short-Baseline (SBL) showed a tension with several phenomenological models. The recent and carefully recomputed anti-neutrino fluxes from nuclear reactors have further increased this tension drawing a picture not fully compatible with the 3 neutrino oscillation scenario. A sterile neutrino is a neutral lepton which does not couple with W/Z bosons. it is not an exotic particle, its existence being a natural consequence of neutrinos having a non-zero mass. Sterile neutrinos can mix with the active ones through additional mass eigenstates, with no necessary mass scale. We will present an experimental search for sterile neutrinos with a new CERN-SPS neutrino beam using muon spectrometers and large LAr detectors. To definitely clarify the physics issue, the proposed experiment will study oscillations in a muon neutrino / antineutrino beam both in appearance and disappearance modes, exploring the Δm 2 ∼ 1 eV 2 range

  11. Probing Neutrino Mass Hierarchy with Supernova

    International Nuclear Information System (INIS)

    Chakraborty, Sovan

    2013-01-01

    The rise time of electron antineutrino lightcurve from a Galactic supernova (SN), observable at the IceCube Cherenkov detector, can provide signature of the neutrino mass hierarchy at “large” 1-3 leptonic mixing angle ϑ 13 . In the early accretion phase of the SN, the neutrino oscillations are nontrivial. Due to the matter suppression of collective effects at these early post bounce times, only the MSW resonances in the outer layers of the SN influence the neutrino flux. When the oscillations are taken into account, the signal in IceCube shows sufficiently fast rise time for the inverted mass hierarchy compared to the normal hierarchy. An investigation with an extensive set of stellar core-collapse simulations, provides both qualitative and quantitative robustness of these features. Thus opening another avenue to explore the neutrino mass hierarchy with the rise time of a supernova burst

  12. Solar neutrinos

    International Nuclear Information System (INIS)

    Phillips, R.J.N.

    1987-09-01

    The problem with solar neutrinos is that there seem to be too few of them, at least near the top end of the spectrum, since the 37 Cl detector finds only about 35% of the standard predicted flux. Various kinds of explanation have been offered: (a) the standard solar model is wrong, (b) neutrinos decay, (c) neutrinos have magnetic moments, (d) neutrinos oscillate. The paper surveys developments in each of these areas, especially the possible enhancement of neutrino oscillations by matter effects and adiabatic level crossing. The prospects for further independent experiments are also discussed. (author)

  13. Measurement of theta13 with reactor neutrinos

    International Nuclear Information System (INIS)

    Heeger, Karsten M.; Freedman, Stuart J.; Kadel, Richard W.; Luk, Kam-Biu

    2004-01-01

    Recent experimental results have provided unambiguous evidence that neutrinos have a small but finite mass and mix from one type into another. The phenomenon of neutrino mixing is characterized by the coupling between the neutrino flavor (nu e,mu,tau ) and mass eigenstates (nu 1,2,3 ) and the associated mixing angles. Previous neutrino oscillation experiments have determined two of the three mixing angles in the neutrino mixing matrix, U MNSP . Using multiple neutrino detectors placed at different distances from a nuclear power plant, a future reactor neutrino experiment has the potential to discover and measure the coupling of the electron neutrino flavor to the third mass eigenstate, U e3 , the last undetermined element of the neutrino mixing matrix

  14. Detecting the (quasi-) two-body decays of /τ leptons in short-baseline neutrino oscillation experiments

    Science.gov (United States)

    Asratyan, A.; Balatz, M.; Boehnlein, D.; Childres, S.; Davidenko, G.; Dolgolenko, A.; Dzyubenko, G.; Kaftanov, V.; Kubantsev, M.; Reay, N. W.; Musser, J.; Rosenfeld, C.; Stanton, N. R.; Thun, R.; Tzanakos, G. S.; Verebryusov, V.; Vishnyakov, V.

    1999-05-01

    Novel detector schemes are proposed for the short-baseline neutrino experiments of next generation, aimed at exploring the large- Δm 2 domain of ν μ→ν τ oscillations in the appearance mode. These schemes emphasize good spectrometry for charged particles and for electromagnetic showers and efficient reconstruction of π0→ γγ decays. The basic elements are a sequence of relatively thin emulsion targets, immersed in magnetic field and interspersed with electronic trackers, and a fine-grained electromagnetic calorimeter built of lead glass. These elements act as an integral whole in reconstructing the electromagnetic showers. This conceptual scheme shows good performance in identifying the τ (quasi-) two-body decays by their characteristic kinematics and in selecting the electronic decays of the τ.

  15. Detecting the (quasi-) two-body decays of τ leptons in short-baseline neutrino oscillation experiments

    International Nuclear Information System (INIS)

    Asratyan, A.; Balatz, M.; Boehnlein, D.; Childres, S.; Davidenko, G.; Dolgolenko, A.; Dzyubenko, G.; Kaftanov, V.; Kubantsev, M.; Reay, N.W.; Musser, J.; Rosenfeld, C.; Stanton, N.R.; Thun, R.; Tzanakos, G.S.; Verebryusov, V.; Vishnyakov, V.

    1999-01-01

    Novel detector schemes are proposed for the short-baseline neutrino experiments of next generation, aimed at exploring the large-Δm 2 domain of ν μ →ν τ oscillations in the appearance mode. These schemes emphasize good spectrometry for charged particles and for electromagnetic showers and efficient reconstruction of π 0 →γγ decays. The basic elements are a sequence of relatively thin emulsion targets, immersed in magnetic field and interspersed with electronic trackers, and a fine-grained electromagnetic calorimeter built of lead glass. These elements act as an integral whole in reconstructing the electromagnetic showers. This conceptual scheme shows good performance in identifying the τ (quasi-) two-body decays by their characteristic kinematics and in selecting the electronic decays of the τ

  16. Neutrino oscillation provides clues to dark matter and signals from the chilled universe

    CERN Multimedia

    2006-01-01

    The new verification that oscillations exists and neutrinos have mass though not detectible easy provides the first clue to extra dimensions, dark matter, hyperspace and chilled universe acting as a platform below it. (1/2 page)

  17. Neutrino Scattering Uncertainties and their Role in Long Baseline Oscillation Experiments

    International Nuclear Information System (INIS)

    D.A. Harris; G. Blazey; Arie Bodek; D. Boehnlein; S. Boyd; William Brooks; Antje Bruell; Howard S. Budd; R. Burnstein; D. Casper; A. Chakravorty; Michael Christy; Jesse Chvojka; M.A.C. Cummings; P. deBarbaro; D. Drakoulakos; J. Dunmore; Rolf Ent; Hugh Gallagher; David Gaskell; Ronald Gilman; Charles Glashausser; Wendy Hinton; Xiaodong Jiang; T. Kafka; O. Kamaev; Cynthia Keppel; M. Kostin; Sergey Kulagin; Gerfried Kumbartzki; Steven Manly; W.A. Mann; Kevin Mcfarland-porter; Wolodymyr Melnitchouk; Jorge Morfin; D. Naples; John Nelson; Gabriel Niculescu; Maria-ioana Niculescu; W. Oliver; Michael Paolone; Emmanuel Paschos; A. Pla-Dalmau; Ronald Ransome; C. Regis; P. Rubinov; V. Rykalin; Willis Sakumoto; P. Shanahan; N. Solomey; P. Spentzouris; P. Stamoulis; G. Tzanakos; Stephen Wood; F.X. Yumiceva; B. Ziemer; M. Zois

    2004-01-01

    The field of oscillation physics is about to make an enormous leap forward in statistical precision: first through the MINOS experiment in the coming year, and later through the NOvA and T2K experiments. Because of the relatively poor understanding of neutrino interactions in the energy ranges of these experiments, there are systematics that can arise in interpreting far detector data that can be as large as or even larger than the expected statistical uncertainties. We describe how these systematic errors arise, and how specific measurements in a dedicated neutrino scattering experiment like MINERvA can reduce the cross section systematic errors to well below the statistical errors

  18. Non-unitarity, sterile neutrinos, and non-standard neutrino interactions

    Energy Technology Data Exchange (ETDEWEB)

    Blennow, Mattias [Department of Theoretical Physics, School of Engineering Sciences, KTH Royal Institute of Technology, Albanova University Center, 106 91 Stockholm (Sweden); Coloma, Pilar [Theoretical Physics Department, Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510 (United States); Fernandez-Martinez, Enrique; Hernandez-Garcia, Josu [Departamento de Física Teórica, Universidad Autónoma de Madrid, Cantoblanco E-28049 Madrid (Spain); Instituto de Física Teórica UAM/CSIC, Calle Nicolás Cabrera 13-15, Cantoblanco E-28049 Madrid (Spain); Lopez-Pavon, Jacobo [INFN, Sezione di Genova, via Dodecaneso 33, 16146 Genova (Italy); CERN, Theoretical Physics Department, Geneva (Switzerland)

    2017-04-27

    The simplest Standard Model extension to explain neutrino masses involves the addition of right-handed neutrinos. At some level, this extension will impact neutrino oscillation searches. In this work we explore the differences and similarities between the case in which these neutrinos are kinematically accessible (sterile neutrinos) or not (mixing matrix non-unitarity). We clarify apparent inconsistencies in the present literature when using different parametrizations to describe these effects and recast both limits in the popular neutrino non-standard interaction (NSI) formalism. We find that, in the limit in which sterile oscillations are averaged out at the near detector, their effects at the far detector coincide with non-unitarity at leading order, even in presence of a matter potential. We also summarize the present bounds existing in both limits and compare them with the expected sensitivities of near-future facilities taking the DUNE proposal as a benchmark. We conclude that non-unitarity effects are too constrained to impact present or near future neutrino oscillation facilities but that sterile neutrinos can play an important role at long baseline experiments. The role of the near detector is also discussed in detail.

  19. Linear stability analysis of collective neutrino oscillations without spurious modes

    Science.gov (United States)

    Morinaga, Taiki; Yamada, Shoichi

    2018-01-01

    Collective neutrino oscillations are induced by the presence of neutrinos themselves. As such, they are intrinsically nonlinear phenomena and are much more complex than linear counterparts such as the vacuum or Mikheyev-Smirnov-Wolfenstein oscillations. They obey integro-differential equations, for which it is also very challenging to obtain numerical solutions. If one focuses on the onset of collective oscillations, on the other hand, the equations can be linearized and the technique of linear analysis can be employed. Unfortunately, however, it is well known that such an analysis, when applied with discretizations of continuous angular distributions, suffers from the appearance of so-called spurious modes: unphysical eigenmodes of the discretized linear equations. In this paper, we analyze in detail the origin of these unphysical modes and present a simple solution to this annoying problem. We find that the spurious modes originate from the artificial production of pole singularities instead of a branch cut on the Riemann surface by the discretizations. The branching point singularities on the Riemann surface for the original nondiscretized equations can be recovered by approximating the angular distributions with polynomials and then performing the integrals analytically. We demonstrate for some examples that this simple prescription does remove the spurious modes. We also propose an even simpler method: a piecewise linear approximation to the angular distribution. It is shown that the same methodology is applicable to the multienergy case as well as to the dispersion relation approach that was proposed very recently.

  20. The ideal neutrino beams

    CERN Document Server

    Lindroos, Mats

    2009-01-01

    The advance in neutrino oscillation physics is driven by the availability of well characterized and high flux neutrino beams. The three present options for the next generation neutrino oscillation facility are super beams, neutrino factories and beta-beams. A super-beam is a very high intensity classical neutrino beam generated by protons impinging on a target where the neutrinos are generated by the secondary particles decaying in a tunnel down streams of the target. In a neutrino factory the neutrinos are generated from muons decaying in a storage ring with long straight sections pointing towards the detectors. In a beta-beam the neutrinos are also originating from decay in a storage ring but the decaying particles are radioactive ions rather than muons. I will in this presentation review the three options and discuss the pros and cons of each. The present joint design effort for a future high intensity neutrino oscillation in Europe within a common EU supported design study, EURONU, will also be presented....

  1. Neutrino oscillations from warped flavor symmetry: Predictions for long baseline experiments T2K, NOvA, and DUNE

    Science.gov (United States)

    Pasquini, Pedro; Chuliá, Salvador Centelles; Valle, J. W. F.

    2017-05-01

    Here we study the pattern of neutrino oscillations emerging from a previously proposed warped standard model construction incorporating Δ (27 ) flavor symmetry [J. High Energy Phys. 01 (2016) 007, 10.1007/JHEP01(2016)007]. In addition to a complete description of fermion masses, the model predicts the lepton mixing matrix in terms of two parameters. The good measurement of θ13 makes these two parameters tightly correlated, leading to an approximate one-parameter description of neutrino oscillations. We find secondary minima for the C P phase absent in the general unconstrained oscillation scenario and determine the fourfold degenerate sharp correlation between the physical C P phase δC P and the atmospheric mixing angle θ23. This implies that maximal θ23 correlates with maximal leptonic C P violation. We perform a realistic estimate of the total neutrino and antineutrino event numbers expected at long baseline oscillation experiments T2K, NOvA, and the upcoming DUNE proposal. We show how an improved knowledge of the C P phase will probe the model in a significant way.

  2. Collective neutrino flavor transitions in supernovae: analytical and numerical aspects

    International Nuclear Information System (INIS)

    Fogli, G L; Marrone, A; Mirizzi, A; Lisi, E

    2008-01-01

    Non-linear effects on supernova neutrino oscillations, associated with neutrino-neutrino interactions, are known to induce collective flavor transformations near the supernova core for θ 13 ≠ 0. For typical electron density profiles (as taken from shock-wave simulations at a few seconds after bounce) these transformations precede ordinary matter effects, and become more amenable to both numerical computations and analytical interpretations in inverted hierarchy-while they basically vanish in normal hierarchy. We numerically evolve the neutrino density matrix in the region relevant for self-interaction effects, using thermal spectra and a representative value sin 2 θ 13 = 10 -4 . Our results neatly show the collective phenomena of synchronization, bipolar oscillations, and spectral split, with analytically understandable features. They also suggest that averaging over neutrino trajectories plays a minor role in the final outcome. The split/swap of (anti)neutrino spectra emerges as an unmistakable signature of the inverted neutrino hierarchy

  3. Search for oscillations of a long-lived muon neutrino beam: a status report

    International Nuclear Information System (INIS)

    Sulak, L.R.; Soukas, A.; Wanderer, P.

    1977-01-01

    A study of the time evolution of a long-lived ν/sub mu/ beam is being performed at Brookhaven National Laboratory (Experiment 704). The proton momentum (1.5 GeV/c 2 ) is chosen to concentrate the ν/sub mu/ flux at very low energy where all background reactions are kinematically suppressed. Sensitivity to oscillations at large proper times tau varies as l/p (where l is the flight length and p is the momentum of the neutrino) is greatly enhanced by the resulting low neutrino momentum. Transformations ν/sub mu/ → ν/sub e/ are sensed via ν/sub e/n → e - p. An early exploratory test using the neutrino detector of the BNL elastic neutrino-proton scattering experiment will be run during 1977. A 200 ton detector for a definitive experiment is also discussed. 14 references

  4. Probing neutrino oscillations jointly in long and very long baseline experiments

    International Nuclear Information System (INIS)

    Wang, Y.F.; Whisnant, K.; Young Binglin; Xiong Zhaohua; Yang Jinmin

    2002-01-01

    We examine the prospects of making a joint analysis of neutrino oscillations at two baselines with neutrino superbeams. Assuming narrow band superbeams and a 100 kiloton water Cherenkov calorimeter, we calculate the event rates and sensitivities to the matter effect, the signs of the neutrino mass differences, the CP phase, and the mixing angle θ 13 . Taking into account all possible experimental errors under general consideration, we explore the optimum cases of a narrow band beam to measure the matter effect and the CP violation effect at all baselines up to 3000 km. We then focus on two specific baselines, a long baseline of 300 km and a very long baseline of 2100 km, and analyze their joint capabilities. We find that the joint analysis can offer extra leverage to resolve some of the ambiguities that are associated with the measurement at a single baseline

  5. Eclipsed neutrinos

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    Full text: The total solar eclipse visible in Southern Asia on 24 October provided an opportunity for an unusual physics experiment. At face value, the levels of solar neutrinos detected on the Earth's surface are difficult to understand and suggest that perhaps the composition of solar neutrinos oscillates between different neutrino types on their journey. In this way neutrinos originating in the Sun as electrontype could convert into heavy neutrinos, which could subsequently disintegrate into an electron-neutrino and a photon. In certain neutrino scenarios, such a photon would have an energy corresponding to that of visible light, and in principle should be detectable if there are enough of them. The problem is that they would normally be swamped by the copious photons of sunlight. The 24 October solar eclipse provided a chance to check this out. A team led by François Vannucci, spokesman of the Nomad neutrino experiment at CERN, en route to the 'Rencontres du Vietnam' physics meeting in Ho Chi Minh Ville, set up a CCD-equipped telescope. To insure against cloud cover, a second telescope followed the eclipse in the desert of Rajastan, India, where the eclipse was to last only half as long, but the chance of cloud was minimal. No background solar signal was seen, or, expressed in physics terms, if solar radiation has any heavy neutrino component, then less than a millionth of it disintegrates into an electron neutrino and a visible photon before it arrives at the Earth. The negative result also has implications for candidate massive, unstable neutrinos from other sources, notably a component of the missing 'dark matter' of the Universe. The next such eclipse should be visible in North Asia in 1997, when hopefully better measurements will be made

  6. Measurement of Atmospheric Neutrino Oscillations at 6-56 GeV with IceCube DeepCore

    Science.gov (United States)

    Aartsen, M. G.; Ackermann, M.; Adams, J.; Aguilar, J. A.; Ahlers, M.; Ahrens, M.; Al Samarai, I.; Altmann, D.; Andeen, K.; Anderson, T.; Ansseau, I.; Anton, G.; Argüelles, C.; Auffenberg, J.; Axani, S.; Bagherpour, H.; Bai, X.; Barron, J. P.; Barwick, S. W.; Baum, V.; Bay, R.; Beatty, J. J.; Becker Tjus, J.; Becker, K.-H.; BenZvi, S.; Berley, D.; Bernardini, E.; Besson, D. Z.; Binder, G.; Bindig, D.; Blaufuss, E.; Blot, S.; Bohm, C.; Börner, M.; Bos, F.; Bose, D.; Böser, S.; Botner, O.; Bourbeau, J.; Bradascio, F.; Braun, J.; Brayeur, L.; Brenzke, M.; Bretz, H.-P.; Bron, S.; Brostean-Kaiser, J.; Burgman, A.; Carver, T.; Casey, J.; Casier, M.; Cheung, E.; Chirkin, D.; Christov, A.; Clark, K.; Classen, L.; Coenders, S.; Collin, G. H.; Conrad, J. M.; Cowen, D. F.; Cross, R.; Day, M.; de André, J. P. A. M.; De Clercq, C.; DeLaunay, J. J.; Dembinski, H.; De Ridder, S.; Desiati, P.; de Vries, K. D.; de Wasseige, G.; de With, M.; DeYoung, T.; Díaz-Vélez, J. C.; di Lorenzo, V.; Dujmovic, H.; Dumm, J. P.; Dunkman, M.; Eberhardt, B.; Ehrhardt, T.; Eichmann, B.; Eller, P.; Evenson, P. A.; Fahey, S.; Fazely, A. R.; Felde, J.; Filimonov, K.; Finley, C.; Flis, S.; Franckowiak, A.; Friedman, E.; Fuchs, T.; Gaisser, T. K.; Gallagher, J.; Gerhardt, L.; Ghorbani, K.; Giang, W.; Glauch, T.; Glüsenkamp, T.; Goldschmidt, A.; Gonzalez, J. G.; Grant, D.; Griffith, Z.; Haack, C.; Hallgren, A.; Halzen, F.; Hanson, K.; Hebecker, D.; Heereman, D.; Helbing, K.; Hellauer, R.; Hickford, S.; Hignight, J.; Hill, G. C.; Hoffman, K. D.; Hoffmann, R.; Hokanson-Fasig, B.; Hoshina, K.; Huang, F.; Huber, M.; Hultqvist, K.; Hünnefeld, M.; In, S.; Ishihara, A.; Jacobi, E.; Japaridze, G. S.; Jeong, M.; Jero, K.; Jones, B. J. P.; Kalaczynski, P.; Kang, W.; Kappes, A.; Karg, T.; Karle, A.; Katz, U.; Kauer, M.; Keivani, A.; Kelley, J. L.; Kheirandish, A.; Kim, J.; Kim, M.; Kintscher, T.; Kiryluk, J.; Kittler, T.; Klein, S. R.; Kohnen, G.; Koirala, R.; Kolanoski, H.; Köpke, L.; Kopper, C.; Kopper, S.; Koschinsky, J. P.; Koskinen, D. J.; Kowalski, M.; Krings, K.; Kroll, M.; Krückl, G.; Kunnen, J.; Kunwar, S.; Kurahashi, N.; Kuwabara, T.; Kyriacou, A.; Labare, M.; Lanfranchi, J. L.; Larson, M. J.; Lauber, F.; Lennarz, D.; Lesiak-Bzdak, M.; Leuermann, M.; Liu, Q. R.; Lu, L.; Lünemann, J.; Luszczak, W.; Madsen, J.; Maggi, G.; Mahn, K. B. M.; Mancina, S.; Maruyama, R.; Mase, K.; Maunu, R.; McNally, F.; Meagher, K.; Medici, M.; Meier, M.; Menne, T.; Merino, G.; Meures, T.; Miarecki, S.; Micallef, J.; Momenté, G.; Montaruli, T.; Moore, R. W.; Moulai, M.; Nahnhauer, R.; Nakarmi, P.; Naumann, U.; Neer, G.; Niederhausen, H.; Nowicki, S. C.; Nygren, D. R.; Obertacke Pollmann, A.; Olivas, A.; O'Murchadha, A.; Palczewski, T.; Pandya, H.; Pankova, D. V.; Peiffer, P.; Pepper, J. A.; Pérez de los Heros, C.; Pieloth, D.; Pinat, E.; Plum, M.; Price, P. B.; Przybylski, G. T.; Raab, C.; Rädel, L.; Rameez, M.; Rawlins, K.; Rea, I. C.; Reimann, R.; Relethford, B.; Relich, M.; Resconi, E.; Rhode, W.; Richman, M.; Robertson, S.; Rongen, M.; Rott, C.; Ruhe, T.; Ryckbosch, D.; Rysewyk, D.; Sälzer, T.; Sanchez Herrera, S. E.; Sandrock, A.; Sandroos, J.; Sarkar, S.; Sarkar, S.; Satalecka, K.; Schlunder, P.; Schmidt, T.; Schneider, A.; Schoenen, S.; Schöneberg, S.; Schumacher, L.; Seckel, D.; Seunarine, S.; Soedingrekso, J.; Soldin, D.; Song, M.; Spiczak, G. M.; Spiering, C.; Stachurska, J.; Stamatikos, M.; Stanev, T.; Stasik, A.; Stettner, J.; Steuer, A.; Stezelberger, T.; Stokstad, R. G.; Stößl, A.; Strotjohann, N. L.; Sullivan, G. W.; Sutherland, M.; Taboada, I.; Tatar, J.; Tenholt, F.; Ter-Antonyan, S.; Terliuk, A.; Tešić, G.; Tilav, S.; Toale, P. A.; Tobin, M. N.; Toscano, S.; Tosi, D.; Tselengidou, M.; Tung, C. F.; Turcati, A.; Turley, C. F.; Ty, B.; Unger, E.; Usner, M.; Vandenbroucke, J.; Van Driessche, W.; van Eijndhoven, N.; Vanheule, S.; van Santen, J.; Vehring, M.; Vogel, E.; Vraeghe, M.; Walck, C.; Wallace, A.; Wallraff, M.; Wandler, F. D.; Wandkowsky, N.; Waza, A.; Weaver, C.; Weiss, M. J.; Wendt, C.; Werthebach, J.; Westerhoff, S.; Whelan, B. J.; Wiebe, K.; Wiebusch, C. H.; Wille, L.; Williams, D. R.; Wills, L.; Wolf, M.; Wood, J.; Wood, T. R.; Woolsey, E.; Woschnagg, K.; Xu, D. L.; Xu, X. W.; Xu, Y.; Yanez, J. P.; Yodh, G.; Yoshida, S.; Yuan, T.; Zoll, M.; IceCube Collaboration

    2018-02-01

    We present a measurement of the atmospheric neutrino oscillation parameters using three years of data from the IceCube Neutrino Observatory. The DeepCore infill array in the center of IceCube enables the detection and reconstruction of neutrinos produced by the interaction of cosmic rays in Earth's atmosphere at energies as low as ˜5 GeV . That energy threshold permits measurements of muon neutrino disappearance, over a range of baselines up to the diameter of the Earth, probing the same range of L /Eν as long-baseline experiments but with substantially higher-energy neutrinos. This analysis uses neutrinos from the full sky with reconstructed energies from 5.6 to 56 GeV. We measure Δ m322=2.31-0.13+0.11×10-3 eV2 and sin2θ23=0.5 1-0.09+0.07, assuming normal neutrino mass ordering. These results are consistent with, and of similar precision to, those from accelerator- and reactor-based experiments.

  7. Pathlength distributions of atmospheric neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Gaisser, T.K.; Stanev, Todor

    1999-01-01

    We discuss the distribution of the production heights of atmospheric neutrinos as a function of zenith angle and neutrino energy. The distributions can be used as the input for evaluation of neutrino propagation under various hypotheses for neutrino flavor oscillations. Their use may alter substantially the estimates of the oscillation parameters for almost horizontal atmospheric neutrinos.

  8. The solar neutrino problem

    International Nuclear Information System (INIS)

    Zatsepin, G.

    1982-01-01

    The problem of missing solar neutrinos is reviewed and discussed. The experiments of the 70s show a solar neutrino flux to be 4 times lower than the flux predicted by the standard model of the Sun. The three possible origins of this contradiction are analysed: the cross sections of nuclear reactions going on in the internal region of the Sun must be remeasured; the unknown properties of neutrino, like neutrino oscillation or decay, must be investigated theoretically and experimentally; or the standard model of the Sun must be changed, e.g. by a periodically pulsating star model or by a model describing periodic admixtures of He-3 to the central region of the Sun. Some new models and newly proposed experiments are described. The importance of new electronic detection methods of neutrinos is underlined. (D.Gy.)

  9. Neutrino properties and neutral currents with their participation

    International Nuclear Information System (INIS)

    Tsukerman, I.S.

    1979-01-01

    Data on the neutrino properties and neutral current with their participation, published in 1977-78 are presented in the lecture. Experimental and cosmological limitations on mass, life time and neutrino oscillations are discussed. Heavy lepton properties and their relation to neutrino are considered. Neutral current data in neutrino-electron, neutrino-proton interactions and in anti νsub(μ)N interactions on nuclei are analyzed. Results of investigations of neutral currents in processes with π meson and strange particle production are given. The lecture material is based on the results presented at the last four international comferences on high energy physics

  10. Mikheyev-Smirnov-Wolfenstein effect in electron-neutrino scattering experiments

    International Nuclear Information System (INIS)

    Bahcall, J.N.; Gelb, J.M.; Rosen, S.P.

    1987-01-01

    We calculate the influence of resonant neutrino scattering [the Mikheyev-Smirnov-Wolfenstein (MSW) effect] in the Sun and in the Earth on measurable quantities in solar-neutrino--electron scattering experiments. The MSW effect reduces the expected rate for 8 B-neutrino--electron scattering by a factor that ranges from --0.8 to --0.2 if resonant scattering is the correct explanation for the discrepancy between observation and calculation in the /sup 37/Cl experiment. The Earth can produce a significant diurnal effect for certain values of the neutrino mixing angle and mass difference

  11. Sterile Neutrinos in Cold Climates

    International Nuclear Information System (INIS)

    Jones, Benjamin J.P.

    2015-01-01

    Measurements of neutrino oscillations at short baselines contain an intriguing set of experimental anomalies that may be suggestive of new physics such as the existence of sterile neutrinos. This three-part thesis presents research directed towards understanding these anomalies and searching for sterile neutrino oscillations. Part I contains a theoretical discussion of neutrino coherence properties. The open-quantum-system picture of neutrino beams, which allows a rigorous prediction of coherence distances for accelerator neutrinos, is presented. Validity of the standard treatment of active and sterile neutrino oscillations at short baselines is verified, and non-standard coherence loss effects at longer baselines are predicted. Part II concerns liquid argon detector development for the MicroBooNE experiment, which will search for short-baseline oscillations in the Booster Neutrino Beam at Fermilab. Topics include characterization and installation of the MicroBooNE optical system; test-stand measurements of liquid argon optical properties with dissolved impurities; optimization of wavelength-shifting coatings for liquid argon scintillation light detection; testing and deployment of high-voltage surge arrestors to protect TPC field cages; and software development for optical and TPC simulation and reconstruction. Part III presents a search for sterile neutrinos using the IceCube neutrino telescope, which has collected a large sample of atmospheric-neutrino-induced events in the 1-10 TeV energy range. Sterile neutrinos would modify the detected neutrino flux shape via MSW-resonant oscillations. Following a careful treatment of systematic uncertainties in the sample, no evidence for MSW-resonant oscillations is observed, and exclusion limits on 3+1 model parameter space are derived. Under the mixing assumptions made, the 90% confidence level exclusion limit extends to sin 2 2θ 24 ≤ 0.02 at m 2 ~ 0.3 eV 2 , and the LSND and MiniBooNE allowed regions are excluded at

  12. The search for neutrino oscillations in the appearance mode nu/sub μ/ → nu/sub e/ for neutrino energies near the muon threshold

    International Nuclear Information System (INIS)

    Huang, Ying-Chiang.

    1986-12-01

    To investigate the possibility of neutrino oscillation, a search for the exclusive mode, nu/sub μ/ → nu/sub e/, was performed at LAMPF. The reactions studied were nu/sub μ/ + C → μ - + X; μ - → e - + anti nu/sub e/ + nu/sub μ/, and nu/sub e/ + C → e - + X (if nu/sub μ/ → nu/sub e/). The detector was located at an effective distance of 20 m from the water target. The beam was composed primarily of muon-neutrinos from pion decay, and the neutrino flux (of mean energy 150 MeV) was computed to be 6.2 x 10 5 nu/cm 2 -sec for 20 μA of proton beam on our target. We saw no evidence for oscillations, and were able to set upper limits sin 2 (2Θ) ≤ 8.8 x 10 -3 (90% C.L.) (in the limit of large Δm 2 ) and Δm 2 sin(2Θ) ≤ 0.59 eV 2 (in the limit of small Δm 2 )

  13. Neutrinos in Nuclear Physics

    Energy Technology Data Exchange (ETDEWEB)

    McKeown, Bob [bmck@jlab.org

    2015-06-01

    Since the discovery of nuclear beta decay, nuclear physicists have studied the weak interaction and the nature of neutrinos. Many recent and current experiments have been focused on the elucidation of neutrino oscillations and neutrino mass. The quest for the absolute value of neutrino mass continues with higher precision studies of the tritium beta decay spectrum near the endpoint. Neutrino oscillations are studied through measurements of reactor neutrinos as a function of baseline and energy. And experiments searching for neutrinoless double beta decay seek to discover violation of lepton number and establish the Majorana nature of neutrino masses.

  14. Measurement of the electroweak coupling of neutrinos and antineutrinos on electrons

    International Nuclear Information System (INIS)

    Jonker, M.

    1983-01-01

    This thesis describes the analysis of the events induced by elastic scattering of neutrinos and antineutrinos on electrons and interprets the results in terms of the coupling strength of (anti)neutrino on electrons. The data for this analysis were obtained with the electronic calorimeter of the CHARM (Amsterdam, Cern, Hamburg, Moscow, Rome) collaboration during the wide band neutrino beam exposures of 1979, 1980 and 1981 in the neutrino facility of the SPS (Super Proton Synchrotron) at CERN (Conseil Europeen pour la Recherche Nucleaire, Geneva, Switzerland). In chapter 1 a historical overview of the early neutrino physics and a description of the phenomenological Lagrangian is given, followed by an introduction to the electroweak unification model. The neutrino detector of the CHARM collaboration is described in chapter 2. Chapter 3 deals with the on-line monitoring system of this detector which has been under the responsibility of the author. The wide band neutrino facility of the CERN SPS is described in chapter 4, followed by a discussion of the experimental method to measure the neutrino energy spectra of the neutrino beams. The electromagnetic shower development process is reviewed in chapter 5 and is followed by a description of the technique that was used to separate showers of electromagnetic and hadronic origin. Chapter 6 discusses the observed signal of the (anti)neutrinos scattering on electrons and interprets these events in terms of the parameters related to the strength of the coupling of neutrinos to electrons. (Auth.)

  15. New phenomena in neutrino physics

    International Nuclear Information System (INIS)

    Kopp, Joachim

    2009-01-01

    In this thesis, we discuss two new concepts in neutrino physics: The neutrino Moessbauer effect and non-standard neutrino interactions. We show that neutrinos emitted and absorbed in recoil-free processes (Moessbauer neutrinos) can oscillate in spite of their near monochromaticity. We support this statement by quantum mechanical wave packet arguments and by a quantum field theoretical (QFT) calculation of the combined rate of Moessbauer neutrino emission, propagation and absorption. The QFT approach does not require any a priori assumptions on the neutrino wave function, and it allows us to include a realistic treatment of the different mechanisms leading to broadening of the emission and absorption lines. In the second part of this work, we study the phenomenology of non-standard neutrino interactions (NSI). We classifying the allowed NSI operators according to their impact on future oscillation experiments and present numerical results for the NSI sensitivities of reactor, superbeam and neutrino factory experiments. We point out that NSI could mimic standard oscillation effects, and might therefore lead to incorrect fit values for the oscillation parameters. For the case of the neutrino factory, we perform a detailed optimisation study to determine the optimum muon energy and detector configuration. (orig.)

  16. New phenomena in neutrino physics

    Energy Technology Data Exchange (ETDEWEB)

    Kopp, Joachim

    2009-04-15

    In this thesis, we discuss two new concepts in neutrino physics: The neutrino Moessbauer effect and non-standard neutrino interactions. We show that neutrinos emitted and absorbed in recoil-free processes (Moessbauer neutrinos) can oscillate in spite of their near monochromaticity. We support this statement by quantum mechanical wave packet arguments and by a quantum field theoretical (QFT) calculation of the combined rate of Moessbauer neutrino emission, propagation and absorption. The QFT approach does not require any a priori assumptions on the neutrino wave function, and it allows us to include a realistic treatment of the different mechanisms leading to broadening of the emission and absorption lines. In the second part of this work, we study the phenomenology of non-standard neutrino interactions (NSI). We classifying the allowed NSI operators according to their impact on future oscillation experiments and present numerical results for the NSI sensitivities of reactor, superbeam and neutrino factory experiments. We point out that NSI could mimic standard oscillation effects, and might therefore lead to incorrect fit values for the oscillation parameters. For the case of the neutrino factory, we perform a detailed optimisation study to determine the optimum muon energy and detector configuration. (orig.)

  17. Neutrino mass hierarchy and three-flavor spectral splits of supernova neutrinos

    International Nuclear Information System (INIS)

    Dasgupta, Basudeb; Mirizzi, Alessandro; Tomas, Ricard; Tamborra, Irene

    2010-01-01

    It was recently realized that three-flavor effects could peculiarly modify the development of spectral splits induced by collective oscillations, for supernova neutrinos emitted during the cooling phase of a protoneutron star. We systematically explore this case, explaining how the impact of these three-flavor effects depends on the ordering of the neutrino masses. In inverted mass hierarchy, the solar mass splitting gives rise to instabilities in regions of the (anti)neutrino energy spectra that were otherwise stable under the leading two-flavor evolution governed by the atmospheric mass splitting and by the 1-3 mixing angle. As a consequence, the high-energy spectral splits found in the electron (anti)neutrino spectra disappear, and are transferred to other flavors. Imperfect adiabaticity leads to smearing of spectral swap features. In normal mass hierarchy, the three-flavor and the two-flavor instabilities act in the same region of the neutrino energy spectrum, leading to only minor departures from the two-flavor treatment.

  18. Density fluctuation effects on collective neutrino oscillations in O-Ne-Mg core-collapse supernovae

    International Nuclear Information System (INIS)

    Cherry, John F.; Fuller, George M.; Wu Mengru; Qian Yongzhong; Carlson, J.; Duan Huaiyu

    2011-01-01

    We investigate the effect of matter density fluctuations on supernova collective neutrino flavor oscillations. In particular, we use full multiangle, three-flavor, self-consistent simulations of the evolution of the neutrino flavor field in the envelope of an O-Ne-Mg core-collapse supernova at shock breakout (neutronization neutrino burst) to study the effect of the matter density ''bump'' left by the He-burning shell. We find a seemingly counterintuitive increase in the overall ν e survival probability created by this matter density feature. We discuss this behavior in terms of the interplay between the matter density profile and neutrino collective effects. While our results give new insights into this interplay, they also suggest an immediate consequence for supernova neutrino burst detection: it will be difficult to use a burst signal to extract information on fossil burning shells or other fluctuations of this scale in the matter density profile. Consistent with previous studies, our results also show that the interplay of neutrino self-coupling and matter fluctuation could cause a significant increase in the ν e survival probability at very low energy.

  19. Probing Neutrino Properties with Long-Baseline Neutrino Beams

    International Nuclear Information System (INIS)

    Marino, Alysia

    2015-01-01

    This final report on an Early Career Award grant began in April 15, 2010 and concluded on April 14, 2015. Alysia Marino's research is focussed on making precise measurements of neutrino properties using intense accelerator-generated neutrino beams. As a part of this grant, she is collaborating on the Tokai-to-Kamioka (T2K) long-baseline neutrino experiment, currently taking data in Japan, and on the Deep Underground Neutrino Experiment (DUNE) design effort for a future Long-Baseline Neutrino Facility (LBNF) in the US. She is also a member of the NA61/SHINE particle production experiment at CERN, but as that effort is supported by other funds, it will not be discussed further here. T2K was designed to search for the disappearance of muon neutrinos (?_?) and the appearance of electron neutrinos (?_e), using a beam of muon neutrino beam that travels 295 km across Japan towards the Super-Kamiokande detector. In 2011 T2K first reported indications of ?_e appearance, a previously unobserved mode of neutrino oscillations. In the past year, T2K has published a combined analysis of ?_? disappearance and ?_e appearance, and began collecting taking data with a beam of anti-neutrinos, instead of neutrinos, to search for hints of violation of the CP symmetry of the universe. The proposed DUNE experiment has similar physics goals to T2K, but will be much more sensitive due to its more massive detectors and new higher-intensity neutrino beam. This effort will be very high-priority particle physics project in the US over the next decade.

  20. Atmospheric neutrino oscillation analysis with external constraints in Super-Kamiokande I-IV

    Science.gov (United States)

    Abe, K.; Bronner, C.; Haga, Y.; Hayato, Y.; Ikeda, M.; Iyogi, K.; Kameda, J.; Kato, Y.; Kishimoto, Y.; Marti, Ll.; Miura, M.; Moriyama, S.; Nakahata, M.; Nakajima, T.; Nakano, Y.; Nakayama, S.; Okajima, Y.; Orii, A.; Pronost, G.; Sekiya, H.; Shiozawa, M.; Sonoda, Y.; Takeda, A.; Takenaka, A.; Tanaka, H.; Tasaka, S.; Tomura, T.; Akutsu, R.; Irvine, T.; Kajita, T.; Kametani, I.; Kaneyuki, K.; Nishimura, Y.; Okumura, K.; Richard, E.; Tsui, K. M.; Labarga, L.; Fernandez, P.; Blaszczyk, F. d. M.; Gustafson, J.; Kachulis, C.; Kearns, E.; Raaf, J. L.; Stone, J. L.; Sulak, L. R.; Berkman, S.; Tobayama, S.; Goldhaber, M.; Carminati, G.; Elnimr, M.; Kropp, W. R.; Mine, S.; Locke, S.; Renshaw, A.; Smy, M. B.; Sobel, H. W.; Takhistov, V.; Weatherly, P.; Ganezer, K. S.; Hartfiel, B. L.; Hill, J.; Hong, N.; Kim, J. Y.; Lim, I. T.; Park, R. G.; Akiri, T.; Himmel, A.; Li, Z.; O'Sullivan, E.; Scholberg, K.; Walter, C. W.; Wongjirad, T.; Ishizuka, T.; Nakamura, T.; Jang, J. S.; Choi, K.; Learned, J. G.; Matsuno, S.; Smith, S. N.; Amey, J.; Litchfield, R. P.; Ma, W. Y.; Uchida, Y.; Wascko, M. O.; Cao, S.; Friend, M.; Hasegawa, T.; Ishida, T.; Ishii, T.; Kobayashi, T.; Nakadaira, T.; Nakamura, K.; Oyama, Y.; Sakashita, K.; Sekiguchi, T.; Tsukamoto, T.; Abe, KE.; Hasegawa, M.; Suzuki, A. T.; Takeuchi, Y.; Yano, T.; Hayashino, T.; Hirota, S.; Huang, K.; Ieki, K.; Jiang, M.; Kikawa, T.; Nakamura, KE.; Nakaya, T.; Patel, N. D.; Suzuki, K.; Takahashi, S.; Wendell, R. A.; Anthony, L. H. V.; McCauley, N.; Pritchard, A.; Fukuda, Y.; Itow, Y.; Mitsuka, G.; Murase, M.; Muto, F.; Suzuki, T.; Mijakowski, P.; Frankiewicz, K.; Hignight, J.; Imber, J.; Jung, C. K.; Li, X.; Palomino, J. L.; Santucci, G.; Vilela, C.; Wilking, M. J.; Yanagisawa, C.; Ito, S.; Fukuda, D.; Ishino, H.; Kayano, T.; Kibayashi, A.; Koshio, Y.; Mori, T.; Nagata, H.; Sakuda, M.; Xu, C.; Kuno, Y.; Wark, D.; Di Lodovico, F.; Richards, B.; Tacik, R.; Kim, S. B.; Cole, A.; Thompson, L.; Okazawa, H.; Choi, Y.; Ito, K.; Nishijima, K.; Koshiba, M.; Totsuka, Y.; Suda, Y.; Yokoyama, M.; Calland, R. G.; Hartz, M.; Martens, K.; Quilain, B.; Simpson, C.; Suzuki, Y.; Vagins, M. R.; Hamabe, D.; Kuze, M.; Yoshida, T.; Ishitsuka, M.; Martin, J. F.; Nantais, C. M.; de Perio, P.; Tanaka, H. A.; Konaka, A.; Chen, S.; Wan, L.; Zhang, Y.; Wilkes, R. J.; Minamino, A.; Super-Kamiokande Collaboration

    2018-04-01

    An analysis of atmospheric neutrino data from all four run periods of Super-Kamiokande optimized for sensitivity to the neutrino mass hierarchy is presented. Confidence intervals for Δ m322 , sin2θ23, sin2θ13 and δC P are presented for normal neutrino mass hierarchy and inverted neutrino mass hierarchy hypotheses, based on atmospheric neutrino data alone. Additional constraints from reactor data on θ13 and from published binned T2K data on muon neutrino disappearance and electron neutrino appearance are added to the atmospheric neutrino fit to give enhanced constraints on the above parameters. Over the range of parameters allowed at 90% confidence level, the normal mass hierarchy is favored by between 91.9% and 94.5% based on the combined Super-Kamiokande plus T2K result.

  1. Evidence and Search for Sterile Neutrinos at Accelerators

    Directory of Open Access Journals (Sweden)

    W. C. Louis

    2013-01-01

    Full Text Available The LSND short-baseline neutrino experiment has published evidence for antineutrino oscillations at a mass scale of ~1 eV2. The MiniBooNE experiment, designed to test this evidence for oscillations at an order of magnitude higher neutrino energy and distance, observes excesses of events in both neutrino mode and antineutrino mode. While the MiniBooNE neutrino excess has a neutrino energy spectrum that is softer than expected from LSND, the MiniBooNE antineutrino excess is consistent with neutrino oscillations and with the LSND oscillation signal. When combined with oscillation measurements at the solar and atmospheric mass scales, assuming that the LSND and MiniBooNE signals are due to neutrino oscillations, these experiments imply the existence of more than three neutrino mass states and, therefore, one or more sterile neutrinos. Such sterile neutrinos, if proven to exist, would have a big impact on particle physics, nuclear physics, and astrophysics and would contribute to the dark matter of the universe. Future experiments under construction or proposed at Fermilab, ORNL, CERN, and in Japan will provide a definitive test of short-baseline neutrino oscillations and will have the capability of proving the existence of sterile neutrinos.

  2. CrossRef Neutrino factory proton driver and target design

    CERN Document Server

    Garoby, Roland; Thomason, John; Davenne, Tristan; Caretta, Ottone; Back, John J

    2016-01-01

    Neutrinos are very elusive particles belonging to the lepton family. They exist in different types corresponding to the different charged leptons, namely electrons, muons and taus. Contrary to electrons, neutrinos hardly interact with matter which makes them very difficult to detect and study. To the best of today’s knowledge, neutrinos have hardly any mass and they can change from one type to another (so-called “neutrino oscillation”). Most physicists think that this oscillation occurs because neutrinos have mass. A Neutrino Factory [1] is a special facility producing a large amount of neutrinos every year (typically 10$^{21}$ neutrinos/year). Its main purpose is to study the change of type of neutrinos between the place where they are generated and a remote location. In a Neutrino Factory, neutrinos result from the decay of muons, unstable particles with a mean lifetime of 2.2 $\\mu$s in their rest frame. Sharp beams of high energy neutrinos are obtained at the end of the long straight sections of a mu...

  3. Study of Neutrino Interactions in MINOS

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Richa [Panjab Univ., Chandigarh (India)

    2014-01-01

    MINOS stands for Main Injector Neutrino Oscillation Search. It is a long baseline experiment located in the USA and is composed of two detectors. The Near Detector is at Fermilab, 1 km from the source of neutrinos. The Far Detector is in Minnesota at a distance of 735 km from the source. Both detectors are steel scintillator tracking calorimeters. MINOS searches for neutrino oscillations by comparing the neutrino energy spectrum at the Far Detector with that obtained from a prediction based on the spectrum at the Near Detector. The primary aim of MINOS is to measure the atmospheric oscillation parameters Δm2 32 and θ23. CPT symmetry requires that these parameters should be same for neutrinos and antineutrinos. Di erences between neutrino and antineutrino oscillations would be an indication of new physics beyond the neutrino-Standard Model ( SM). Additionally, violation of Lorentz or CPT symmetry could also give rise to oscillations di erent from that expected from the SM predictions, such as neutrino to antineutrino transitions.

  4. First events from the CNGS neutrino beam detected in the OPERA experiment

    CERN Document Server

    Acquafredda, R.; Ambrosio, M.; Anokhina, A.; Aoki, S.; Ariga, A.; Arrabito, L.; Autiero, D.; Badertscher, A.; Bergnoli, A.; Bersani Greggio, F.; Besnier, M.; Beyer, M.; Bondil-Blin, S.; Borer, K.; Boucrot, J.; Boyarkin, V.; Bozza, C.; Brugnera, R.; Buontempo, S.; Caffari, Y.; Campagne, Jean-Eric; Carlus, B.; Carrara, E.; Cazes, A.; Chaussard, L.; Chernyavsky, M.; Chiarella, V.; Chon-Sen, N.; Chukanov, A.; Ciesielski, R.; Consiglio, L.; Cozzi, M.; Dal Corso, F.; D'Ambrosio, N.; Damet, J.; De Lellis, G.; Declais, Y.; Descombes, T.; De Serio, M.; Di Capua, F.; Di Ferdinando, D.; Di Giovanni, A.; Di Marco, N.; Di Troia, C.; Dmitrievski, S.; Dracos, M.; Duchesneau, D.; Dulach, B.; Dusini, S.; Ebert, J.; Enikeev, R.; Ereditato, A.; Esposito, L.S.; Fanin, C.; Favier, J.; Felici, G.; Ferber, T.; Fournier, L.; Franceschi, A.; Frekers, D.; Fukuda, T.; Fukushima, C.; Galkin, V.I.; Galkin, V.A.; Gallet, R.; Garfagnini, A.; Gaudiot, G.; Giacomelli, G.; Giarmana, O.; Giorgini, M.; Girard, L.; Girerd, C.; Goellnitz, C.; Goldberg, J.; Gornoushkin, Y.; Grella, G.; Grianti, F.; Guerin, C.; Guler, M.; Gustavino, C.; Hagner, C.; Hamane, T.; Hara, T.; Hauger, M.; Hess, M.; Hoshino, K.; Ieva, M.; Incurvati, M.; Jakovcic, K.; Janicsko Csathy, J.; Janutta, B.; Jollet, C.; Juget, F.; Kazuyama, M.; Kim, S.H.; Kimura, M.; Knuesel, J.; Kodama, K.; Kolev, D.; Komatsu, M.; Kose, U.; Krasnoperov, A.; Kreslo, I.; Krumstein, Z.; Laktineh, I.; de La Taille, C.; Le Flour, T.; Lieunard, S.; Ljubicic, A.; Longhin, A.; Malgin, A.; Manai, K.; Mandrioli, G.; Mantello, U.; Marotta, A.; Marteau, J.; Martin-Chassard, G.; Matveev, V.; Messina, M.; Meyer, L.; Micanovic, S.; Migliozzi, P.; Miyamoto, S.; Monacelli, Piero; Monteiro, I.; Morishima, K.; Moser, U.; Muciaccia, M.T.; Mugnier, P.; Naganawa, N.; Nakamura, M.; Nakano, T.; Napolitano, T.; Natsume, M.; Niwa, K.; Nonoyama, Y.; Nozdrin, A.; Ogawa, S.; Olchevski, A.; Orlandi, D.; Ossetski, D.; Paoloni, A.; Park, B.D.; Park, I.G.; Pastore, A.; Patrizii, L.; Pellegrino, L.; Pessard, H.; Pilipenko, V.; Pistillo, C.; Polukhina, N.; Pozzato, M.; Pretzl, K.; Publichenko, P.; Raux, L.; Repellin, J.P.; Roganova, T.; Romano, G.; Rosa, G.; Rubbia, A.; Ryasny, V.; Ryazhskaya, O.; Ryzhikov, D.; Sadovski, A.; Sanelli, C.; Sato, O.; Sato, Y.; Saveliev, V.; Savvinov, N.; Sazhina, G.; Schembri, A.; Schmidt Parzefall, W.; Schroeder, H.; Schutz, H.U.; Scotto Lavina, L.; Sewing, J.; Shibuya, H.; Simone, S.; Sioli, M.; Sirignano, C.; Sirri, G.; Song, J.S.; Spaeti, R.; Spinetti, M.; Stanco, L.; Starkov, N.; Stipcevic, M.; Strolin, Paolo Emilio; Sugonyaev, V.; Takahashi, S.; Tereschenko, V.; Terranova, F.; Tezuka, I.; Tioukov, V.; Tikhomirov, I.; Tolun, P.; Toshito, T.; Tsarev, V.; Tsenov, R.; Ugolino, U.; Ushida, N.; Van Beek, G.; Verguilov, V.; Vilain, P.; Votano, L.; Vuilleumier, J.L.; Waelchli, T.; Waldi, R.; Weber, M.; Wilquet, G.; Wonsak, B.; Wurth, R.; Wurtz, J.; Yakushev, V.; Yoon, C.S.; Zaitsev, Y.; Zamboni, I.; Zimmerman, R.

    2006-01-01

    The OPERA neutrino detector at the underground Gran Sasso Laboratory (LNGS) was designed to perform the first detection of neutrino oscillations in appearance mode, through the study of nu_mu to nu_tau oscillations. The apparatus consists of a lead/emulsion-film target complemented by electronic detectors. It is placed in the high-energy, long-baseline CERN to LNGS beam (CNGS) 730 km away from the neutrino source. In August 2006 a first run with CNGS neutrinos was successfully conducted. A first sample of neutrino events was collected, statistically consistent with the integrated beam intensity. After a brief description of the beam and of the various sub-detectors, we report on the achievement of this milestone, presenting the first data and some analysis results.

  5. Electron-neutrino scattering off nuclei from two different theoretical perspectives

    Science.gov (United States)

    Martini, M.; Jachowicz, N.; Ericson, M.; Pandey, V.; Van Cuyck, T.; Van Dessel, N.

    2016-07-01

    We analyze charged-current electron-neutrino cross sections on carbon. We consider two different theoretical approaches, on one hand the continuum random phase approximation (CRPA) which allows a description of giant resonances and quasielastic excitations, on the other hand the RPA-based calculations which are able to describe multinucleon emission and coherent and incoherent pion production as well as quasielastic excitations. We compare the two approaches in the genuine quasielastic channel, and find a satisfactory agreement between them at large energies while at low energies the collective giant resonances show up only in the CRPA approach. We also compare electron-neutrino cross sections with the corresponding muon-neutrino ones in order to investigate the impact of the different charged-lepton masses. Finally, restricting to the RPA-based approach, we compare the sum of quasielastic, multinucleon emission, coherent, and incoherent one-pion production cross sections (folded with the electron-neutrino T2K flux) with the charged-current inclusive electron-neutrino differential cross sections on carbon measured by T2K. We find a good agreement with the data. The multinucleon component is needed in order to reproduce the T2K electron-neutrino inclusive cross sections.

  6. Interpreting OPERA results on superluminal neutrino

    CERN Document Server

    Giudice, Gian F; Strumia, Alessandro

    2012-01-01

    OPERA has claimed the discovery of superluminal propagation of neutrinos. We analyze the consistency of this claim with previous tests of special relativity. We find that reconciling the OPERA measurement with information from SN1987a and from neutrino oscillations requires stringent conditions. The superluminal limit velocity of neutrinos must be nearly flavor independent, must decrease steeply in the low-energy domain, and its energy dependence must depart from a simple power law. We construct illustrative models that satisfy these conditions, by introducing Lorentz violation in a sector with light sterile neutrinos. We point out that, quite generically, electroweak quantum corrections transfer the information of superluminal neutrino properties into Lorentz violations in the electron and muon sector, in apparent conflict with experimental data.

  7. Solar neutrino results and Violation of the Equivalence Principle An analysis of the existing data and predictions for SNO

    CERN Document Server

    Majumdar, D; Sil, A; Majumdar, Debasish; Raychaudhuri, Amitava; Sil, Arunansu

    2001-01-01

    Violation of the Equivalence Principle (VEP) can lead to neutrino oscillation through the non-diagonal coupling of neutrino flavor eigenstates with the gravitational field. The neutrino energy dependence of this oscillation probability is different from that of the usual mass-mixing neutrino oscillations. In this work we explore, in detail, the viability of the VEP hypothesis as a solution to the solar neutrino problem in a two generation scenario with both the active and sterile neutrino alternatives, choosing these states to be massless. To obtain the best-fit values of the oscillation parameters we perform a chi square analysis for the total rates of solar neutrinos seen at the Chlorine (Homestake), Gallium (Gallex and SAGE), Kamiokande, and SuperKamiokande (SK) experiments. We find that the goodness of these fits is never satisfactory. It markedly improves if the Chlorine data is excluded from the analysis, especially for VEP transformation to sterile neutrinos. The 1117-day SK data for recoil electron sp...

  8. The KASKA project - a Japanese medium-baseline reactor-neutrino oscillation experiment to measure the mixing angle $\\theta_{13}$ -

    OpenAIRE

    Kuze, Masahiro; Collaboration, for the KASKA

    2005-01-01

    A new reactor-neutrino oscillation experiment, KASKA, is proposed to measure the unknown neutrino-mixing angle $\\theta_{13}$ using the world's most powerful Kashiwazaki-Kariwa nuclear power station. It will measure a very small deficit of reactor-neutrino flux using three identical detectors, two placed just close to the sources and one at a distance of about 1.8km. Its conceptual design and physics reach are discussed.

  9. Super-Kamiokande Solar Neutrino Results and NSI Analysis

    Science.gov (United States)

    Weatherly, Pierce; Super-Kamiokande Collaboration

    2017-09-01

    Super-Kamiokande (SK) detects the Cerenkov light from elastic scattering of solar 8B neutrinos with electrons in its ultra-pure water. The directionality, energy, and timing of the recoil electrons determines the interaction rate, the flight path, as well as the energy dependence of the 8B neutrinos’ electron-flavor survival probability P ee . While the P ee below 1 MeV is equivalent to averaged vacuum neutrino flavor oscillations, the P ee above 7 MeV is suppressed by the Mikheyev-Smirnov-Wolfenstein (MSW) resonance resulting from the interaction of the solar neutrinos with solar matter. In the same way, Earth matter effects influence Pee, leading to an apparent Day/Night effect. Non-standard interactions (NSI) extend the MSW model to include interactions between the quarks in matter and neutrinos, thereby modifying P ee . We present the signatures of matter effects on solar neutrinos in Super-Kamiokande and present limits on NSI parameters, in particular couplings to the down quark.

  10. Neutrinoless double beta decay and the solar neutrino problem

    International Nuclear Information System (INIS)

    Petcov, S.T.; Smirnov, A.Yu.

    1993-10-01

    The MSW or vacuum oscillation solution of the solar neutrino problem can be reconciled with possible existence of the (ββ) oν decay with a half-line corresponding to an effective Majorana mass of the electron neutrino modul m ee approx. (0.1 - 1.0) eV. The phenomenological consequences of such a possibility are analyzed and the implications for the mechanisms of neutrino mass generation are considered. (author). 31 refs, 2 figs

  11. MUNU: study of the neutrino-electron scattering; MUNU: etude de la diffusion neutrino-electron

    Energy Technology Data Exchange (ETDEWEB)

    Cerna, C

    2000-11-01

    MUNU is an experiment dedicated to electron-neutrino scattering studies and in particular to neutrino magnetic moment search at a nuclear power plant in Bugey (France). MUNU is based on a gaseous time projection chamber (TPC) immersed in 8 tons of liquid scintillator acting as an active anti-Compton shielding. A preliminary analysis of the first results of this experiment corresponding to about 24 days of data collecting draws a line on the value of the neutrino magnetic moment: {mu}{sub {nu}}-bar{sub {sub e}} {<=} 1.97 10{sup -10} {mu}{sub B} (68% confidence level). All along this work, it is shown that the combined use of a TPC and of a light detection system is valuable for discriminating particles and for discarding signals from background noise.

  12. Neutrino mixing and future accelerator neutrino experiments

    International Nuclear Information System (INIS)

    Bilenky, S.M.

    1992-01-01

    No evidence for neutrino mixing has been obtained in experiments searching for oscillations with neutrinos from accelerators and reactors. The possible reason is that neutrino masses are too small to produce any sizable effects in the experiments with terrestrial neutrinos. We put forward here the point of view that the reason for that can be traced to the presence of a hierarchy of neutrino masses as well as strength of couplings between lepton families. (orig.)

  13. Detecting supernova neutrinos in Daya Bay Neutrino Laboratory

    International Nuclear Information System (INIS)

    Huang Mingyang; Guo Xinheng; Yang Binglin

    2011-01-01

    While detecting supernova neutrinos in the Daya Bay neutrino laboratory, several supernova neutrino effects need to be considered, including the supernova shock effects, the neutrino collective effects, the Mikheyev-Smirnov-Wolfenstein (MSW) effects, and the Earth matter effects. The phenomena of neutrino oscillation is affected by the above effects. Using some ratios of the event numbers of different supernova neutrinos, we propose some possible methods to identify the mass hierarchy and acquire information about the neutrino mixing angle θ13 and neutrino masses. (authors)

  14. Measurement of Neutrino Oscillation Parameters Using Anti-fiducial Charged Current Events in MINOS

    Energy Technology Data Exchange (ETDEWEB)

    Strait, Matthew Levy [Univ. of Minnesota, Minneapolis, MN (United States)

    2010-09-01

    Abstract The Main Injector Neutrino Oscillation Search (MINOS) obse rves the disappearance of muon neutrinos as they propagate in the long baseline Neutri nos at the Main Injector (NuMI) beam. MINOS consists of two detectors. The near detector sam ples the initial composition of the beam. The far detector, 735 km away, looks for an energy-d ependent deficit in the neutrino spectrum. This energy-dependent deficit is interpreted as q uantum mechanical oscillations be- tween neutrino flavors. A measurement is made of the effective two-neutrino mixing parameters Δ m 2 ≈ Δ m 2 23 and sin 2 2 θ ≈ sin 2 2 θ 23 . The primary MINOS analysis uses charged current events in the fiducial volume of the far detector. This analysis uses the roughly equal-sized sample of events that fails the fiducial cut, consisting of interact ions outside the fiducial region of the detector and in the surrounding rock. These events provide a n independent and complementary measurement, albeit weaker due to incomplete reconstructi on of the events. This analysis reports on an exposure of 7 . 25 × 10 20 protons-on-target. Due to poor energy resolution, the meas urement of sin 2 2 θ is much weaker than established results, but the measuremen t of sin 2 2 θ > 0 . 56 at 90% confidence is consistent with the accepted value. The measur ement of Δ m 2 is much stronger. Assuming sin 2 2 θ = 1 , Δ m 2 = (2 . 20 ± 0 . 18[stat] ± 0 . 14[syst]) × 10 - -3 eV 2 .

  15. MINOS Sterile Neutrino Search

    Energy Technology Data Exchange (ETDEWEB)

    Koskinen, David Jason [Univ. College London, Bloomsbury (United Kingdom)

    2009-02-01

    The Main Injector Neutrino Oscillation Search (MINOS) is a long-baseline accelerator neutrino experiment designed to measure properties of neutrino oscillation. Using a high intensity muon neutrino beam, produced by the Neutrinos at Main Injector (NuMI) complex at Fermilab, MINOS makes two measurements of neutrino interactions. The first measurement is made using the Near Detector situated at Fermilab and the second is made using the Far Detector located in the Soudan Underground laboratory in northern Minnesota. The primary goal of MINOS is to verify, and measure the properties of, neutrino oscillation between the two detectors using the v μ→ Vτ transition. A complementary measurement can be made to search for the existence of sterile neutrinos; an oft theorized, but experimentally unvalidated particle. The following thesis will show the results of a sterile neutrino search using MINOS RunI and RunII data totaling ~2.5 x 1020 protons on target. Due to the theoretical nature of sterile neutrinos, complete formalism that covers transition probabilities for the three known active states with the addition of a sterile state is also presented.

  16. Neutrino Physics

    CERN Multimedia

    CERN. Geneva; Dydak, Friedrich

    2001-01-01

    Starting from a review of theoretical concepts and experimental results in the early years of neutrino physics after Pauli's 1930 letter, today's double role of the neutrino as a cornerstone of the Standard Model and as a promising probe of physics beyond the Standard Model will be discussed. Topics comprise: - Conventional neutrino beams - Neutrinos as probes of the nucleon structure - Neutrinos from the universe - Dirac or Majorana neutrinos - Neutrino oscillations - MNS matrix - CP violation in the lepton sector - Neutrino factory.

  17. Neutrino Physics

    CERN Multimedia

    CERN. Geneva. Audiovisual Unit

    2002-01-01

    Starting from a review of theoretical concepts and experimental results in the early years of neutrino physics after Pauli's 1930 letter, today's double role of the neutrino as a cornerstone of the Standard Model and as a promising probe of physics beyond the Standard Model will be discussed. Topics comprise: - Conventional neutrino beams - Neutrinos as probes of the nucleon structure - Neutrinos from the universe - Dirac or Majorana neutrinos - Neutrino oscillations - MNS matrix - CP violation in the lepton sector - Neutrino factory.

  18. Reines-Cowan team discovery of the electron neutrino

    International Nuclear Information System (INIS)

    Kruse, Herald W.

    2011-01-01

    Personal perspective and recollections by the author discuss the Reines-Cowan team discovery of the electron neutrino at a Savannah River reactor in 1956. First presented at the Neutrino Santa Fe 2006 Conference.

  19. Neutrinos (1/3)

    CERN Multimedia

    CERN. Geneva

    2013-01-01

    The neutrino, the lightest and most weakly interacting particle of the Standard Model has revealed itself as the messenger of very exciting news in particle physics: there is Physics Beyond the Standard Model. All this thanks to the quantum-mechanical phenomenon of flavour oscillations which is intrinsically connected to the question of neutrino mass and which has been observed in neutrinos produced in natural sources, like the Sun and the Earth's atmosphere, as well as with human made neutrino beams at accelerator and reactors. The purpose of these lectures is to overview some aspects of the phenomenology of massive neutrinos. I will present the simplest extensions for adding neutrino masses to the SM, and then I will describe the phenomenology associated with neutrino oscillations in vacuum and in matter and its present signatures.

  20. Sterile Neutrinos in Cold Climates

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Benjamin J.P. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    2015-09-01

    Measurements of neutrino oscillations at short baselines contain an intriguing set of experimental anomalies that may be suggestive of new physics such as the existence of sterile neutrinos. This three-part thesis presents research directed towards understanding these anomalies and searching for sterile neutrino oscillations. Part I contains a theoretical discussion of neutrino coherence properties. The open-quantum-system picture of neutrino beams, which allows a rigorous prediction of coherence distances for accelerator neutrinos, is presented. Validity of the standard treatment of active and sterile neutrino oscillations at short baselines is verified, and non-standard coherence loss effects at longer baselines are predicted. Part II concerns liquid argon detector development for the MicroBooNE experiment, which will search for short-baseline oscillations in the Booster Neutrino Beam at Fermilab. Topics include characterization and installation of the MicroBooNE optical system; test-stand measurements of liquid argon optical properties with dissolved impurities; optimization of wavelength-shifting coatings for liquid argon scintillation light detection; testing and deployment of high-voltage surge arrestors to protect TPC field cages; and software development for optical and TPC simulation and reconstruction. Part III presents a search for sterile neutrinos using the IceCube neutrino telescope, which has collected a large sample of atmospheric-neutrino-induced events in the 1-10 TeV energy range. Sterile neutrinos would modify the detected neutrino flux shape via MSW-resonant oscillations. Following a careful treatment of systematic uncertainties in the sample, no evidence for MSW-resonant oscillations is observed, and exclusion limits on 3+1 model parameter space are derived. Under the mixing assumptions made, the 90% confidence level exclusion limit extends to sin224 ≤ 0.02 at m2 ~ 0.3 eV2, and the LSND and Mini

  1. Acceleration and propagation of cosmic rays. Production, oscillation and detection of neutrinos

    International Nuclear Information System (INIS)

    Lagage, P.O.

    1987-01-01

    This thesis is devoted to studies on cosmic rays and neutrinos, particles astrophysically relevant. In recent years, the old problem of cosmic-ray acceleration and propagation has become alive again, with the discovery of the diffusive shock acceleration mechanism, and with the first measurements of the cosmic-ray antiproton flux, which appears to be higher than expected. I have shown that the new acceleration mechanism was slow and I have calculated the maximum energy that can be reached by particles accelerated in various astrophysical sites. I have also studied in detail a cosmic-ray propagation model which takes into account the antiproton measurements. Neutrino astronomy is a field much more recent and in rapid expansion, thanks to a convergence of interests between astrophysicists and elementary particle physicists. Several large neutrino detectors already exist; really huge ones are in project. I have studied the possible impact of the high energy (> 1 TeV) neutrino astronomy on models of cosmic-ray sources such as Cygnus X3. Comparing the low energy (∼ 10 MeV) cosmic-ray antineutrinos with other sources of neutrinos and antineutrinos (sun, supernova, earth ...), I have pointed out that the antineutrino background resulting from all the nuclear power-stations of the planet was sizeable. This background is a nuisance for some astrophysical applications but could be useful for studies on vacuum or matter neutrino oscillations (MSW effect). I have also examined the MSW effect in another context: the travel through the earth of neutrinos from the supernova explosion SN1987a [fr

  2. Neutrino oscillation parameter sampling with MonteCUBES

    Science.gov (United States)

    Blennow, Mattias; Fernandez-Martinez, Enrique

    2010-01-01

    We present MonteCUBES ("Monte Carlo Utility Based Experiment Simulator"), a software package designed to sample the neutrino oscillation parameter space through Markov Chain Monte Carlo algorithms. MonteCUBES makes use of the GLoBES software so that the existing experiment definitions for GLoBES, describing long baseline and reactor experiments, can be used with MonteCUBES. MonteCUBES consists of two main parts: The first is a C library, written as a plug-in for GLoBES, implementing the Markov Chain Monte Carlo algorithm to sample the parameter space. The second part is a user-friendly graphical Matlab interface to easily read, analyze, plot and export the results of the parameter space sampling. Program summaryProgram title: MonteCUBES (Monte Carlo Utility Based Experiment Simulator) Catalogue identifier: AEFJ_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEFJ_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU General Public Licence No. of lines in distributed program, including test data, etc.: 69 634 No. of bytes in distributed program, including test data, etc.: 3 980 776 Distribution format: tar.gz Programming language: C Computer: MonteCUBES builds and installs on 32 bit and 64 bit Linux systems where GLoBES is installed Operating system: 32 bit and 64 bit Linux RAM: Typically a few MBs Classification: 11.1 External routines: GLoBES [1,2] and routines/libraries used by GLoBES Subprograms used:Cat Id ADZI_v1_0, Title GLoBES, Reference CPC 177 (2007) 439 Nature of problem: Since neutrino masses do not appear in the standard model of particle physics, many models of neutrino masses also induce other types of new physics, which could affect the outcome of neutrino oscillation experiments. In general, these new physics imply high-dimensional parameter spaces that are difficult to explore using classical methods such as multi-dimensional projections and minimizations, such as those

  3. Progress in neutrino oscillation searches and their implications

    Indian Academy of Sciences (India)

    is maximal (irrespective of the value of mixing angle in vacuum) for an electron density .... From this decay chain one expects the number of muon neutrinos to be about twice that ..... [11] M Honda, T Kajita, S Midorikawa and K Kasahara, Phys.

  4. The mass of the electron neutrino and electron capture in 163Ho

    International Nuclear Information System (INIS)

    Yasumi, S.; Rajasekaran, G.; Ando, M.; Ochiai, F.; Ikeda, H.; Ohta, T.; Stefan, P.M.; Maruyama, M.; Nashimoto, N.; Fujioka, M.; Ishii, K.; Shinozuka, T.; Sera, K.; Omori, T.; Izawa, G.; Yagi, M.; Masumoto, K.; Shima, K.

    1983-01-01

    To determine the mass of the electron neutrino, electron capture in 163 Ho was studied. From the intensity of M X-rays and the total number of 163 Ho atoms in a source, as determined by the PIXE method, the partial M-capture half life of 163 Ho was estimated to be (4.5 +- 1.5) x 10 4 yr. A relation between the Q-value of 163 Ho and the mass of the electron neutrino was obtained. (orig.)

  5. Possible Tau Appearance Experiment with Atmospheric Neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Stanev, Todor

    1999-12-27

    We suggest an experimental measurement that could detect the appearance of tau neutrinos due to {nu}{sub {mu}}{yields}{nu}{sub {tau}} oscillations of atmospheric neutrinos by measuring the energy spectra of neutrino induced showers. {tau} neutrinos deposit a large fraction of their energy in showers generated by {nu}{sub {tau}} charge current interactions and the subsequent {tau} -lepton decay. The appearance of {nu}{sub {tau}} will enhance the spectrum of neutrino induced showers in energy ranges corresponding to the neutrino oscillation parameters. A shower rate lower than the ''no oscillation'' prediction is an indication for {nu}{sub {mu}}{yields}{nu}{sub s} oscillations. (c) 1999 The American Physical Society.

  6. Future neutrino experiments

    CERN Document Server

    Di Lella, L

    2001-01-01

    Future experiments to search for neutrino oscillations using neutrinos from the Sun, from reactors and accelerators are reviewed. Possible long-term developments based on neutrino factories are also described. (29 refs).

  7. A search for neutrino–antineutrino mass inequality by means of sterile neutrino oscillometry

    Energy Technology Data Exchange (ETDEWEB)

    Smirnov, M.V., E-mail: gear8mike@gmail.com [Department of Physics, University of Jyväskylä, 40014 Jyväskylä (Finland); St. Petersburg State University, 198504 Peterhof, St. Petersburg (Russian Federation); Loo, K.K. [Department of Physics, University of Jyväskylä, 40014 Jyväskylä (Finland); Novikov, Yu.N. [St. Petersburg State University, 198504 Peterhof, St. Petersburg (Russian Federation); Petersburg Nuclear Physics Institute, 188300 Gatchina, St. Petersburg (Russian Federation); Trzaska, W.H. [Department of Physics, University of Jyväskylä, 40014 Jyväskylä (Finland); Wurm, M. [Johannes Gutenberg University Mainz, 55099 Mainz (Germany)

    2015-11-15

    The investigation of the oscillation pattern induced by the sterile neutrinos might determine the oscillation parameters, and at the same time, allow to probe CPT symmetry in the leptonic sector through neutrino–antineutrino mass inequality. We propose to use a large scintillation detector like JUNO or LENA to detect electron neutrinos and electron antineutrinos from MCi electron capture or beta decay sources. Our calculations indicate that such an experiment is realistic and could be performed in parallel to the current research plans for JUNO and RENO. Requiring at least 5σ confidence level and assuming the values of the oscillation parameters indicated by the current global fit, we would be able to detect neutrino–antineutrino mass inequality of the order of 0.5% or larger, which would imply a signal of CPT anomalies.

  8. Atmospheric Neutrinos in the MINOS Far Detector

    Energy Technology Data Exchange (ETDEWEB)

    Howcroft, Caius Leo Frederick [Univ. of Cambridge (United Kingdom)

    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 vμ and $\\bar{v}$μ 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.

  9. Observation of muon-electron pairs in neutrino reactions

    International Nuclear Information System (INIS)

    Hoffmann, D.

    1980-05-01

    The present thesis describes the observation of muon-electron pairs in neutrino reactions. This experiment was performed using an optical multiplate spark chamber in the broad band neutrino beam of the CERN proton synchrotron. (orig.) [de

  10. Acceleration and propagation of cosmic radiation. Production, oscillation and detection of neutrinos

    International Nuclear Information System (INIS)

    Lagage, P.-O.

    1987-06-01

    In recent years, the old problem of cosmic-ray acceleration and propagation has become alive again, with the discovery of the diffusive shock acceleration mechanism, and with the first measurements of the cosmic-ray antiproton flux, which appears to be higher than expected. I have shown that the new acceleration mechanism was slow and I have calculated the maximum energy that can be reached by particles accelerated in various astrophysical sites. I have also studied in detail a cosmic-ray propagation model which takes into account the antiproton measurements. Neutrino astronomy is a field much more recent and in rapid expansion, thanks to a convergence of interests between astrophysicists and elementary particle physicists. Several large neutrino detectors already exist; really huge ones are in project. I have studied the possible impact of the high energy (> 1 TeV) neutrino astronomy on models of cosmic-ray sources such as Cygnus X3. Comparing the low energy (∼ 10 MeV) cosmic-ray antineutrinos with other sources of neutrinos and antineutrinos (sun, supernova, earth...), I have pointed out that the antineutrino background resulting from all the nuclear power-stations of the planet was sizeable. This background is a nuisance for some astrophysical applications but could be useful for studies on vacuum or matter neutrino oscillations (MSW effect). I have also examined the MSW effect in another context: the travel through the earth of neutrinos from the supernova explosion SN1987a [fr

  11. Precision positioning of SuperKamiokande with GPS for a long-baseline neutrino oscillation experiment

    International Nuclear Information System (INIS)

    Noumi, H.; Ieiri, M.; Ishii, H.; Katoh, Y.; Minakawa, M.; Nakamura, K.; Nishikawa, K.; Suzuki, Y.; Takasaki, M.; Tanaka, K.H.; Yamanoi, Y.; Kurodai, M.; Kasa, H.; Yoshimura, K.

    1997-01-01

    A positioning of the neutrino detector superkamiokande (SK) was made for a long-baseline neutrino oscillation experiment planned at KEK. For positioning, global positioning system (GPS) was employed. It has been demonstrated that GPS is of practical use for measuring the positions of SK and KEK, being 250 km distance from each other, to a better resolution. The geodetic coordinates at the SK center were obtained to be Lat. 36 25'32.5862'' N., Long. 137 18'37.1241'' E., H. 371.839 m in the global ellipsoidal coordinate system, WGS-84. The obtained coordinates are based on the coordinates given at a triangulation point at the KEK site. The present work will be fed back for constructing the neutrino beam line. (orig.)

  12. Letter on intent to build an off-axis detector to study nu sub m sub u-> nu sub e oscillations with the NuMI neutrino beam. Version 6.0

    CERN Document Server

    Ayres, D; Guarino, V; Joffe-Minor, T M; Reyna, D; Talaga, R; Thron, J

    2003-01-01

    The question of neutrino masses is of fundamental importance. Neutrino oscillations seem to be the only tool available to us to unravel the pattern of neutrino masses and, perhaps, shed some light on the origin of masses in general. The NuMI neutrino beam line and the MINOS experiment represent a major investment of US High Energy Physics in the area of neutrino physics. the forthcoming results could decisively establish neutrino oscillations as the underlying physics mechanism for the atmospheric nu submu deficit and provide a precise measurement of the corresponding oscillation parameters, DELTA m sub 3 sub 2 sup 2 and sin sup 2 2 theta sub 2 sub 3. This, however, is just a beginning of a long journey into uncharted territories. The key to these new territories is the detection of nu submu -> nu sub e oscillations associated with the atmospheric nu submu deficit, controlled by the little known mixing angle sin sup 2 2 theta sub 1 sub 3. A precise measurement of the amplitude of these oscillations will enabl...

  13. Experimental constraints on a minimal and nonminimal violation of the equivalence principle in the oscillations of massive neutrinos

    International Nuclear Information System (INIS)

    Gasperini, M.; Istituto Nazionale di Fisica Nucleare, Sezione di Torino, Torino, Italy)

    1989-01-01

    The negative results of the oscillations experiments are discussed with the hypothesis that the various neutrino types are not universally coupled to gravity. In this case the transition probabiltiy between two different flavor eigenstates may be affected by the local gravitational field present in a terrestrial laboratory, and the contribution of gravity can interfere, in general, with the mass contribution to the oscillation process. In particular it is shown that even a strong violation of the equivalence principle could be compatible with the experimental data, provided the gravity-induced energy splitting is balanced by a suitable neutrino mass difference

  14. Lepton mixing and the 'solar neutrino puzzle'

    International Nuclear Information System (INIS)

    Bilenky, S.M.; Pontecorvo, B.

    1977-01-01

    The results of the well-known solar neutrino experiments in which the Cl-Ar method was employed are discussed; the results of this experiment gave a too-small neutrino signal and were referred to as the 'solar neutrino puzzle'. A number of explanations have been offered to account for the results, but it is stated that the explanation in terms of lepton mixing and neutrino sterility is attractive in terms of present day elementary particle physics and much more natural than the other explanations offered. Headings are as follows: neutrino oscillations and lepton charge, oscillations and solar neutrino experiments, lepton mixing according to old and present ideas, neutrino oscillations and the 'solar neutrino puzzle'. (U.K.)

  15. The ideal neutrino beams

    Science.gov (United States)

    Lindroos, Mats

    2009-06-01

    The advance in neutrino oscillation physics is driven by the availability of well characterized and high flux neutrino beams. The three present options for the next generation neutrino oscillation facility are super beams, neutrino factories and beta-beams. A super-beam is a very high intensity classical neutrino beam generated by protons impinging on a target where the neutrinos are generated by the secondary particles decaying in a tunnel down streams of the target. In a neutrino factory the neutrinos are generated from muons decaying in a storage ring with long straight sections pointing towards the detectors. In a beta-beam the neutrinos are also originating from decay in a storage ring but the decaying particles are radioactive ions rather than muons. I will in this presentation review the three options and discuss the pros and cons of each. The present joint design effort for a future high intensity neutrino oscillation in Europe within a common EU supported design study, EURONU, will also be presented. The design study will explore the physics reach, the detectors, the feasibility, the safety issues and the cost for each of the options so that the the community can take a decision on what to build when the facilities presently under exploitation and construction have to be replaced.

  16. Search for neutrino oscillation anti νμ→ anti νe with the KARMEN experiment

    International Nuclear Information System (INIS)

    Rapp, J.M.

    1996-04-01

    The neutrino experiment KARMEN at the neutron spallation source ISIS at the Rutherford Appleton Laboratory in England makes use of neutrinos generated by the decay chain of π + produced in the spallation process. The π + and the subsequent μ + decay at rest generates ν μ , ν e and anti ν μ which are emitted isotropically with equal intensity and well defined energies (E ν e from the π - decay chain is less than 0.1%. The unique time structure of the ISIS proton synchrotron allows a separation of ν μ from anti ν μ and ν e by time measurement. The KARMEN-detector is a large volume calorimeter of 67 m 3 liquid organic scintillator, situated about 17 m from the ν-source, investigating neutrino-nucleus interactions at low energies. Cross sections of nuclear excitations through the charged and neutral weak currents spectroscopic quality and the μ-e-universality is tested at energies less than 53 MeV. Further objectives of KARMEN are the search for neutrino flavour oscillations and lepton number violating decays of pions and muons. This work presents the limits for anti ν μ → anti ν e oscillations in the appearance channel obtained after five years of measuring time (July 90-July 95). The data are predominantly evaluated on the basis of a multi-parameter maximum likelihood analysis. (orig.)

  17. Determining neutrino mass hierarchy from electron disappearance at a low energy neutrino factory

    International Nuclear Information System (INIS)

    Raut, Sushant K.

    2013-01-01

    Reactor neutrino experiments have recently measured the value of θ 13 , to be non-zero and moderately large. This makes the determination of the neutrino mass hierarchy possible. However, our lack of knowledge of δ CP results in a parameter degeneracy, which makes this task difficult. The electron neutrino disappearance probability does not depend on δ CP . Therefore, in principle, it is possible to determine the hierarchy independently of δ CP using this channel. Previous studies of neutrino factories have not considered this channel, because the effect of systematics in electron disappearance is substantial. However, we show that for the moderately large value of θ 13 measured, hierarchy determination is possible in spite of systematic effects. We consider a low energy neutrino factory (LENF) setup with a totally active scintillator detector (TASD) with charge-identification. We optimize the setup in muon energy and baseline, for different allowed values of θ 13 and runtime. We find that a LENF with baseline of around 1300 km and muon energy around 3-4 GeV is well suited for hierarchy determination. For the RENO best-fit value of θ 13 , this setup can determine the hierarchy at 5ω, for all values of δ CP and for both hierarchies. (author)

  18. Proton driver optimization for new-generation neutrino superbeams to search for sub-leading νμ→νe oscillations (θ13 angle)

    International Nuclear Information System (INIS)

    Ferrari, A; Rubbia, A; Rubbia, C; Sala, P R

    2002-01-01

    In this paper, we perform a systematic study of particle production and neutrino yields for different incident proton energies E p and baselines L, with the aim of optimizing the parameters of a neutrino beam for the investigation of θ 13 -driven neutrino oscillations in the Δm 2 range allowed by Superkamiokande results. We study the neutrino energy spectra in the 'relevant' region of the first maximum of the oscillation at a given baseline L. We find that to each baseline L corresponds an 'optimal' proton energy E p which minimizes the required integrated proton intensity needed to observe a fixed number of oscillated events. In addition, we find that the neutrino event rate in the relevant region scales approximately linearly with the proton energy. Hence, baselines L and proton energies E p can be adjusted and the performance for neutrino oscillation searches will remain approximately unchanged provided that the product of the proton energy times the number of protons on target remains constant. We apply these ideas to the specific cases of 2.2, 4.4, 20, 50 and 400 GeV protons. We simulate focusing systems that are designed to best capture the secondary pions of the 'optimal' energy. We compute the expected sensitivities to sin 2 2θ 13 for the various configurations by assuming the existence of new-generation accelerators able to deliver integrated proton intensities on target times the proton energy of the order of O(5x10 23 ) GeVxpot/year

  19. Neutrino physics at LAMPF

    International Nuclear Information System (INIS)

    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 μ/ → /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 π + at rest. It is also useful to realize that, on average, an 800-MeV proton from LAMPF produces about 0.1 π + decaying at rest. 16 refs., 5 figs., 4 tabs

  20. Neutrino Oscillations

    Indian Academy of Sciences (India)

    The 2015 Nobel Prize in Physics was awarded to two physicists-Takaaki Kajita and Arthur B McDonald, whose teams discoveredthat neutrinos, which come in three flavours, changefrom one flavour to another. This discovery is a major milestonein particle physics as it gives a clear evidence of physicsbeyond the Standard ...

  1. EFFECTS OF NEUTRINO ELECTROMAGNETIC FORM FACTORS ON NEUTRINO INTERACTION WITH FINITE TEMPERATURE ELECTRON MATTERS

    Directory of Open Access Journals (Sweden)

    Anto Sulaksono

    2011-11-01

    Full Text Available The differential cross-section of neutrino interaction with dense and warm electron gasses has been calculated by takinginto account the neutrino electromagnetic form factors. The significant effect of electromagnetic properties of neutrinocan be found if the neutrino dipole moment, μ ν , is ≥ 5.10-9 μB and neutrino charge radius, Rv, is ≥ 5.10-6 MeV-1. Theimportance of the retarded correction, detailed balance and Pauli blocking factors is shown and analyzed. Many-bodyeffects on the target matter which are included via random phase approximation (RPA correlation as well as photoneffective mass are also investigated.

  2. Exact and approximate formulas for neutrino mixing and oscillations with non-standard interactions

    International Nuclear Information System (INIS)

    Meloni, Davide; Ohlsson, Tommy; Zhang, He

    2009-01-01

    We present, both exactly and approximately, a complete set of mappings between the vacuum (or fundamental) leptonic mixing parameters and the effective ones in matter with non-standard neutrino interaction (NSI) effects included. Within the three-flavor neutrino framework and a constant matter density profile, a full set of sum rules is established, which enables us to reconstruct the moduli of the effective leptonic mixing matrix elements, in terms of the vacuum mixing parameters in order to reproduce the neutrino oscillation probabilities for future long-baseline experiments. Very compact, but quite accurate, approximate mappings are obtained based on series expansions in the neutrino mass hierarchy parameter η ≡ Δm 2 21 /Δm 2 31 , the vacuum leptonic mixing parameter s 13 ≡ sin θ 13 , and the NSI parameters ε αβ . A detailed numerical analysis about how the NSIs affect the smallest leptonic mixing angle θ 13 , the deviation of the leptonic mixing angle θ 23 from its maximal mixing value, and the transition probabilities useful for future experiments are performed using our analytical results.

  3. Mikheyev-Smirnov-Wolfenstein effect with flavor-changing neutrino interactions

    International Nuclear Information System (INIS)

    Roulet, E.

    1991-01-01

    We consider the effect that flavor-nondiagonal neutrino interactions with matter have on the resonant ν oscillations. It is shown that, even in the absence of ν mixing in a vacuum, an efficient conversion of the electron neutrinos from the Sun to another ν flavor can result if the strength of this interaction is ∼10 -2 G F . We show how this can be implemented in the minimal supersymmetric standard model with R-parity breaking. Here, the L-violating couplings induce neutrino masses, mixings, and the flavor-nondiagonal neutrino interactions that can provide a Mikheyev-Smirnov-Wolfenstein-like solution to the solar-neutrino problem even for negligible vacuum mixings

  4. Very long baseline neutrino oscillation experiments for precise measurments of oscillation parameters and search for n Mu yields n epsilon.

    CERN Document Server

    Diwan, M; Brennan, M; Chen, M C; Fernow, R; Marciano, W; Weng, W

    2002-01-01

    Brookhaven National Laboratory and collaborators started a neutrino working group to identify new opportunities in the field of neutrino oscillations and explore how our laboratory facilities can be used to explore this field of research. The memo to the working group and the charge are included in Appendix I. This report is the result of the deliberations of the working group. Previously, we wrote a letter of intent to build a new high intensity neutrino beam at BNL. A new intense proton beam will be used to produce a conventional horn focused neutrino beam directed at a detector located in either the Homestake mine in Lead, South Dakota at 2540 km or the Waste Isolation Pilot Plant (WIPP) in Carlsbad, NM at 2880 km. As a continuation of the study that produced the letter of intent, this report examines several items in more detail. We mainly concentrate on the use of water Cherenltov detectors because of their size, resolution, and background rejection capability, and cost. We examine the prospects of build...

  5. A study of the interactions of high energy electron-neutrinos

    International Nuclear Information System (INIS)

    Nieuwenhuis, C.H.M.

    1986-01-01

    This thesis describes an analysis of electron-neutrino and anti-neutrino interactions with nuclei. The data were collected with the calorimeter of the Amsterdam-CERN-Hamburg-Moscow-Rome (CHARM) group in a beam dump exposure to 400 GeV/c protons from the CERN SPS in 1982. The predictions of the Standard Model for the quantities measured in this experiment are given. The results of the analysis of events without a primary muon in the final state are given in the form of an experimental y-distribution. The measured quantities are compared with the predictions of the theory and the measurements of other experiments. Presented are the cross-section ratio of neutral current and charged current electron-neutrino induced events, the prompt CC ν(anti ν) e interaction rate, the prompt (ν e +anti ν e )/(ν μ +anti ν μ ) flux ratio, the energy dependence of the prompt electron-neutrino flux and a measurement of the DantiD cross-section times semileptonic branching ratio based on prompt electron-neutrino interactions. (Auth.)

  6. From cosmic OPERA to neutrino ballet

    CERN Multimedia

    2006-01-01

    View of the OPERA detector (on the CNGS facility) with its two identical Super Modules, each of which contains one target section and one spectrometer.As the CNGS (CERN Neutrinos to Gran Sasso) project prepares to send its high intensity neutrino beam, some 730 km away in Italy, the OPERA collaboration is beginning to commission its electronic detectors in the underground Gran Sasso National Laboratory (LNGS). OPERA is ready to come on stage. Based in the INFN Gran Sasso National Laboratory, 732 km from CERN, the experiment will commission its electronic detectors with the high intensity neutrino beam sent by CNGS (see Bulletin n°29-30/2006). The OPERA Collaboration, which comprises 170 physicists from 35 research institutes and universities worldwide, aims to clear up the mystery of neutrino oscillation. The installation of the OPERA detector began in 2003 in Hall C of the underground laboratory at the LNGS. The detector is made of two identical Super Modules, each one containing one target section and ...

  7. Search for neutrino oscillations νμ→ντ in the decay channel: τ→ρ of the NOMAD experiment

    International Nuclear Information System (INIS)

    Besson, N.

    1999-10-01

    The purpose of the NOMAD experiment is to find the oscillations of muon-neutrinos into tau-neutrinos by detecting the presence of tau-neutrinos in a beam made up essentially of muon-neutrinos. The first part of this thesis is dedicated to neutrinos, to the open questions in neutrino physics and gives the elements necessary to understand the oscillation phenomenon. The second part presents the principle on which is based the NOMAD experiment and the NOMAD detector is described. NOMAD detector is made up of 49 big drift chambers. The data collected allow the reconstruction of interaction vertex, of tracks of charged particles and give accurate values of energies and impulses involved in the process. A very important point is the alignment of the chambers and their efficiency. This thesis is a contribution to the improvement of reconstruction methods. The aim of NOMAD detector is to reveal the presence of tau-neutrino by detecting the decay products of the τ - issued from the current charged interaction of the tau-neutrino with the target. 5 channels of the τ - decay are opened to NOMAD detector but the hadronic channel: τ - → ρ - is the most interesting because of its high branching ratio (25.3%). The fourth part describes the analysis methods which are based on various decay topologies of ρ. (A.C.)

  8. Present and future oscillation experiments at reactors

    International Nuclear Information System (INIS)

    Mikaehlyan, L.A.

    2001-01-01

    A report is presented on recent progress and developments (since the NANP'99 Conference) in the current and future long baseline (∼100 - 800 km) oscillation experiments at reactors. These experiments, under certain assumptions, can fully reconstruct the internal mass structure of the electron neutrino and provide a laboratory test of solar and atmospheric neutrino problems

  9. Solar neutrino problem accounting for self-consistent magnetohydrodynamics solution for solar magnetic fields

    International Nuclear Information System (INIS)

    Miranda, O.G.; Pena-Garay, C.; Valle, J.W.F.; Rashba, T.I.; Semikoz, V.B.

    2001-01-01

    The analysis of the resonant spin-flavour (RSF) solutions to the solar neutrino problem in the framework of the simplest analytical solutions to the solar magnetohydrodynamics (MHD) equations is presented. We performed the global fit of the recent solar neutrino data, including event rates as well as zenith angle distributions and recoil electron spectra induced by solar neutrino interactions in Superkamiokande. We compare quantitatively our simplest MHD-RSF fit with vacuum oscillation (VAC) and MSW-type (SMA, LMA and LOW) solutions to the solar neutrino problem using a common well-calibrated theoretical calculation and fit procedure and find MHD-RSF fit to be somewhat better than those obtained for the favored neutrino oscillation solutions. We made the predictions for future experiments (e.g., SNO) to disentangle the MHD-RSF scenario from other scenarios

  10. Non-Unitarity, sterile neutrinos, and Non-Standard neutrino Interactions

    CERN Document Server

    Blennow, Mattias; Fernandez-Martinez, Enrique; Hernandez-Garcia, Josu; Lopez-Pavon, Jacobo

    2017-04-27

    The simplest Standard Model extension to explain neutrino masses involves the addition of right-handed neutrinos. At some level, this extension will impact neutrino oscillation searches. In this work we explore the differences and similarities between the case in which these neutrinos are kinematically accessible (sterile neutrinos) or not (mixing matrix non-unitarity). We clarify apparent inconsistencies in the present literature when using different parametrizations to describe these effects and recast both limits in the popular neutrino non-standard interaction (NSI) formal- ism. We find that, in the limit in which sterile oscillations are averaged out at the near detector, their effects at the far detector coincide with non-unitarity at leading order, even in presence of a matter potential. We also summarize the present bounds existing in both limits and compare them with the expected sensitivities of near-future facilities taking the DUNE proposal as a bench- mark. We conclude that non-unitarity effects ...

  11. Study of the expected performance of the T2K experiment on muon neutrino to electron neutrino oscillation using data from K2K experiment

    International Nuclear Information System (INIS)

    Fechner, M.

    2006-05-01

    T2K is a neutrino oscillation experiment that will use the intense 2.5 degrees off-axis ν μ beam produced at J-PARC (Japan). The far detector is Super-Kamiokande (SK), the 50 kt water Cherenkov detector located 295 km from J-PARC. The goal is to search for ν e appearance, which will bring new information on θ 13 . The main background for ν e appearance comes from intrinsic beam ν e events (∼ 55%), and from mis-identified neutral current π 0 events (∼ 45%); near detectors are needed to measure these background components before oscillation. A detector complex (2KM) including a water Cherenkov detector, located ∼ 1.8 km away from the source is under active study. This distance is advantageous because the neutrino spectrum is only a few percent different from that of SK, thereby reducing extrapolation systematics. In order to match SK performance, the water Cherenkov detector was designed with ∼ 5600 8-inch photo-multiplier tubes, after studies based on full simulation tuned to K2K data. The water Cherenkov reconstruction algorithms, mainly particle identification and e/π 0 separation, were also studied at 2KM. Studies of ν e appearance in the water Cherenkov detector show that using simple scaling extrapolation we conservatively predict 23.0 ± 8.0% (stat + syst) background events at SK for 5. 10 21 p.o.t., in excellent agreement with the 23.8 background events obtained from an independent simulation of SK. The 2KM detector can achieve background subtraction to better than 10% accuracy, sufficient for T2K phase I. Detailed sensitivity studies, including all the relevant sources of systematics, show that the 2KM detector improves the sensitivity to sin 2 (2θ 13 ) down to ∼ 1.4. 10 -2 at 90% CL. (author)

  12. Muon-Neutrino Electron Elastic Scattering and a Search for the Muon-Neutrino Magnetic Moment in the NOvA Near Detector

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Biao [Southern Methodist U.

    2017-01-01

    We use the NOvA near detector and the NuMI beam at Fermilab to study the neutrino- electron elastic scattering and the muon neutrino magnetic process beyond the Standard Model physics. The particle identications of neutrino on electron elastic scattering are trained by using the multi-layer neural networks. This thesis provides a general discussion of this technique and shows a good agreement between data and MC for the neutrino-electron elastic weak scattering. So that beneting from the precise cross-section of this channel, we are able to tune the neutrino beam ux simulation in the future. Giving the exposure of 3:62 1020 POT in the NOvA near detector, we report 1:58 10

  13. Supernova neutrinos and explosive nucleosynthesis

    Science.gov (United States)

    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 θ13, 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 θ13, 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.

  14. Supernova neutrinos and explosive nucleosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Kajino, T. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan and Department of Astronomy, Graduate School of Science, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033 (Japan); Aoki, W. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Cheoun, M.-K. [Department of Physics, Soongsil University, Seoul 156-743 (Korea, Republic of); Hayakawa, T. [Japan Atomic Energy Agency, Shirakara-Shirane 2-4, Tokai-mura, Ibaraki 319-1195 (Japan); Hidaka, J.; Hirai, Y.; Shibagaki, S. [National Astronomical Observatory, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Mathews, G. J. [Center for Astrophysics, Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Nakamura, K. [Faculty of Science and Engineering, Waseda University, Ohkubo 3-4-1, Shinjuku, Tokyo 169-8555 (Japan); Suzuki, T. [Department of Physics, College of Humanities and Sciences, Nihon University, Sakurajosui 3-25-40, Setagaya-ku, Tokyo 156-8550 (Japan)

    2014-05-09

    Core-collapse supernovae eject huge amount of flux of energetic neutrinos. We studied the explosive nucleosyn-thesis in supernovae and found that several isotopes {sup 7}Li, {sup 11}B, {sup 92}Nb, {sup 138}La and {sup 180}Ta 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 θ{sub 13}, simultaneously. There is recent evidence that SiC X grains from the Murchison meteorite may contain supernova-produced light elements {sup 11}B and {sup 7}Li encapsulated in the presolar grains. Combining the recent experimental constraints on θ{sub 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.

  15. Parameter degeneracies in neutrino oscillation measurement of leptonic CP and T violation

    International Nuclear Information System (INIS)

    Minakata, Hisakazu; Nunokawa, Hiroshi; Parke, Stephen

    2002-01-01

    The measurement of the mixing angle θ 13 , sign of Δm 13 2 , and the CP or T violating phase δ is fraught with ambiguities in neutrino oscillation. In this paper we give an analytic treatment of the parameter degeneracies associated with measuring the ν μ →ν e probability and its CP and/or T conjugates. For CP violation, we give explicit solutions to allow us to obtain the regions where there exist twofold and fourfold degeneracies. We calculate the fractional differences, (Δθ/θ-bar), between the allowed solutions which may be used to compare with the expected sensitivities of the experiments. For T violation we show that there is always a complete degeneracy between solutions with positive and negative Δm 13 2 which arises due to a symmetry and cannot be removed by observing one neutrino oscillation probability and its T conjugate. Thus there is always a fourfold parameter degeneracy apart from exceptional points. Explicit solutions are also given and the fractional differences are computed. The biprobability CP/T trajectory diagrams are extensively used to illuminate the nature of the degeneracies

  16. Mirror model for sterile neutrinos

    International Nuclear Information System (INIS)

    Berezinsky, Veniamin; Narayan, Mohan; Vissani, Francesco

    2003-01-01

    Sterile neutrinos are studied as subdominant contribution to solar neutrino physics. The mirror-matter neutrinos are considered as sterile neutrinos. We use the symmetric mirror model with gravitational communication between mirror and visible sectors. This communication term provides mixing between visible and mirror neutrinos with the basic scale μ=v EW 2 /M Pl =2.5x10 -6 eV, where v EW =174 GeV is the vacuum expectation value of the standard electroweak group and M Pl is the Planckian mass. It is demonstrated that each mass eigenstate of active neutrinos splits into two states separated by small Δm 2 . Unsuppressed oscillations between active and sterile neutrinos (ν a ↔ν s ) occur only in transitions between each of these close pairs ('windows'). These oscillations are characterized by very small Δm 2 and can suppress the flux and distort spectrum of pp-neutrinos in detectable way. The other observable effect is anomalous seasonal variation of neutrino flux, which appears in LMA solution. The considered subdominant neutrino oscillations ν a ↔ν s can reveal itself as big effects in observations of supernova neutrinos and high-energy (HE) neutrinos. In the case of HE neutrinos they can provide a very large diffuse flux of active neutrinos unconstrained by the e-m cascade upper limit

  17. A letter of intent for a neutrino scattering experiment on the booster neutrino meanline: FINeSSE

    Energy Technology Data Exchange (ETDEWEB)

    Fleming, B.T.; Tayloe, R.; /Indiana U. /Yale U.

    2005-03-01

    The experiment described in this Letter of Intent provides a decisive measurement of {Delta}s, the spin of the nucleon carried by strange quarks. This is crucial as, after more than thirty years of study, the spin contribution of strange quarks to the nucleon is still not understood. The interpretation of {Delta}s measurements from inclusive Deep Inelastic Scattering (DIS) experiments using charged leptons suffers from two questionable techniques; an assumption of SU(3)-flavor symmetry, and an extrapolation into unmeasured kinematic regions, both of which provide ample room for uncertain theoretical errors in the results. The results of recent semi-inclusive DIS data from HERMES paint a somewhat different picture of the contribution of strange quarks to the nucleon spin than do the inclusive results, but since HERMES does not make use of either of the above-mentioned techniques, then the results are somewhat incomparable. What is required is a measurement directly probing the spin contribution of the strange quarks in the nucleon. Neutrino experiments provide a theoretically clean and robust method of determining {Delta}s by comparing the neutral current interaction, which is isoscalar plus isovector, to the charged current interaction, which is strictly isovector. A past experiment, E734, performed at Brookhaven National Laboratory, has pioneered this effort. Building on what they have learned, we present an experiment which achieves a measurement to {+-} 0.025 using neutrino scattering, and {+-} 0.04 using anti-neutrino scattering, significantly better than past measurements. The combination of the neutrino and anti-neutrino data, when combined with the results of the parity-violating electron-nucleon scattering data, will produce the most significant result for {Delta}s. This experiment can also measure neutrino cross sections in the energy range required for accelerator-based precision oscillation measurements. Accurate measurements of cross sections have been

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

    International Nuclear Information System (INIS)

    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

  19. The experimental status of neutrino masses and mixings

    International Nuclear Information System (INIS)

    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 indications that neutrino oscillations are occurring. Other evidence for new physics is less consistent and convincing

  20. Sterile neutrinos beyond LSND at the neutrino factory

    International Nuclear Information System (INIS)

    Meloni, Davide; Tang Jian; Winter, Walter

    2010-01-01

    We discuss the effects of one additional sterile neutrino at the Neutrino Factory. Compared to earlier analyses, which have been motivated by Liquid Scintillator Neutrino Detector (LSND) results, we do not impose any constraint on the additional mass squared splitting. This means that the additional mass eigenstate could, with small mixings, be located among the known ones, as it is suggested by the recent analysis of cosmological data. We use a self-consistent framework at the Neutrino Factory without any constraints on the new parameters. We demonstrate for a combined short and long baseline setup that near detectors can provide the expected sensitivity at the LSND-motivated Δm 41 2 -range, while some sensitivity can also be obtained in the region of the atmospheric mass splitting from the long baselines. We point out that limits on such very light sterile neutrinos may also be obtained from a reanalysis of atmospheric and solar neutrino oscillation data, as well as from supernova neutrino observations. In the second part of the analysis, we compare our sensitivity with the existing literature using additional assumptions, such as |Δm 41 2 |>>|Δm 31 2 |, leading to averaging of the fast oscillations in the far detectors. We demonstrate that while the Neutrino Factory has excellent sensitivity compared to existing studies using similar assumptions, one has to be very careful interpreting these results for a combined short and long baseline setup where oscillations could occur in the near detectors. We also test the impact of additional ν τ detectors at the short and long baselines, and we do not find a substantial improvement of the sensitivities.

  1. Measurement of the Cosmic Ray and Neutrino-Induced Muon Flux at the Sudbury Neutrino Observatory

    Science.gov (United States)

    SNO collaboration; Aharmim, B.; Ahmed, S. N.; Andersen, T. C.; Anthony, A. E.; Barros, N.; Beier, E. W.; Bellerive, A.; Beltran, B.; Bergevin, M.; Biller, S. D.; Boudjemline, K.; Boulay, M. G.; Burritt, T. H.; Cai, B.; Chan, Y. D.; Chen, M.; Chon, M. C.; Cleveland, B. T.; Cox-Mobrand, G. A.; Currat, C. A.; Dai, X.; Dalnoki-Veress, F.; Deng, H.; Detwiler, J.; Doe, P. J.; Dosanjh, R. S.; Doucas, G.; Drouin, P.-L.; Duncan, F. A.; Dunford, M.; Elliott, S. R.; Evans, H. C.; Ewan, G. T.; Farine, J.; Fergani, H.; Fleurot, F.; Ford, R. J.; Formaggio, J. A.; Gagnon, N.; Goon, J. TM.; Grant, D. R.; Guillian, E.; Habib, S.; Hahn, R. L.; Hallin, A. L.; Hallman, E. D.; Hargrove, C. K.; Harvey, P. J.; Harvey, P. J.; Heeger, K. M.; Heintzelman, W. J.; Heise, J.; Helmer, R. L.; Hemingway, R. J.; Henning, R.; Hime, A.; Howard, C.; Howe, M. A.; Huang, M.; Jamieson, B.; Jelley, N. A.; Klein, J. R.; Kos, M.; Kruger, A.; Kraus, C.; Krauss, C. B.; Kutter, T.; Kyba, C. C. M.; Lange, R.; Law, J.; Lawson, I. T.; Lesko, K. T.; Leslie, J. R.; Levine, I.; Loach, J. C.; Luoma, S.; MacLellan, R.; Majerus, S.; Mak, H. B.; Maneira, J.; Marino, A. D.; Martin, R.; McCauley, N.; McDonald, A. B.; McGee, S.; Mifflin, C.; Miller, M. L.; Monreal, B.; Monroe, J.; Noble, A. J.; Oblath, N. S.; Okada, C. E.; O'Keeffe, H. M.; Opachich, Y.; Orebi Gann, G. D.; Oser, S. M.; Ott, R. A.; Peeters, S. J. M.; Poon, A. W. P.; Prior, G.; Rielage, K.; Robertson, B. C.; Robertson, R. G. H.; Rollin, E.; Schwendener, M. H.; Secrest, J. A.; Seibert, S. R.; Simard, O.; Simpson, J. J.; Sinclair, D.; Skensved, P.; Smith, M. W. E.; Sonley, T. J.; Steiger, T. D.; Stonehill, L. C.; Tagg, N.; Tesic, G.; Tolich, N.; Tsui, T.; Van de Water, R. G.; VanDevender, B. A.; Virtue, C. J.; Waller, D.; Waltham, C. E.; Wan Chan Tseung, H.; Wark, D. L.; Watson, P.; Wendland, J.; West, N.; Wilkerson, J. F.; Wilson, J. R.; Wouters, J. M.; Wright, A.; Yeh, M.; Zhang, F.; Zuber, K.

    2009-07-10

    Results are reported on the measurement of the atmospheric neutrino-induced muon flux at a depth of 2 kilometers below the Earth's surface from 1229 days of operation of the Sudbury Neutrino Observatory (SNO). By measuring the flux of through-going muons as a function of zenith angle, the SNO experiment can distinguish between the oscillated and un-oscillated portion of the neutrino flux. A total of 514 muon-like events are measured between -1 {le} cos {theta}{sub zenith} 0.4 in a total exposure of 2.30 x 10{sup 14} cm{sup 2} s. The measured flux normalization is 1.22 {+-} 0.09 times the Bartol three-dimensional flux prediction. This is the first measurement of the neutrino-induced flux where neutrino oscillations are minimized. The zenith distribution is consistent with previously measured atmospheric neutrino oscillation parameters. The cosmic ray muon flux at SNO with zenith angle cos {theta}{sub zenith} > 0.4 is measured to be (3.31 {+-} 0.01 (stat.) {+-} 0.09 (sys.)) x 10{sup -10} {micro}/s/cm{sup 2}.

  2. Los Alamos Science, Number 25 -- 1997: Celebrating the neutrino

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, N.G. [ed.

    1997-12-31

    This issue is devoted to the neutrino and its remaining mysteries. It is divided into the following areas: (1) The Reines-Cowan experiment -- detecting the poltergeist; (2) The oscillating neutrino -- an introduction to neutrino masses and mixing; (3) A brief history of neutrino experiments at LAMPF; (4) A thousand eyes -- the story of LSND (Los Alamos neutrino oscillation experiment); (5) The evidence for oscillations; (6) The nature of neutrinos in muon decay and physics beyond the Standard Model; (7) Exorcising ghosts -- in pursuit of the missing solar neutrinos; (8) MSW -- a possible solution to the solar neutrino problem; (8) Neutrinos and supernovae; and (9) Dark matter and massive neutrinos.

  3. Los Alamos Science, Number 25 -- 1997: Celebrating the neutrino

    International Nuclear Information System (INIS)

    Cooper, N.G.

    1997-01-01

    This issue is devoted to the neutrino and its remaining mysteries. It is divided into the following areas: (1) The Reines-Cowan experiment -- detecting the poltergeist; (2) The oscillating neutrino -- an introduction to neutrino masses and mixing; (3) A brief history of neutrino experiments at LAMPF; (4) A thousand eyes -- the story of LSND (Los Alamos neutrino oscillation experiment); (5) The evidence for oscillations; (6) The nature of neutrinos in muon decay and physics beyond the Standard Model; (7) Exorcising ghosts -- in pursuit of the missing solar neutrinos; (8) MSW -- a possible solution to the solar neutrino problem; (8) Neutrinos and supernovae; and (9) Dark matter and massive neutrinos

  4. Searching for Sterile Neutrinos with MINOS

    Energy Technology Data Exchange (ETDEWEB)

    Timmons, Ashley [Manchester U.

    2016-01-01

    This document presents the latest results for a 3+1 sterile neutrino search using the $10.56 \\times 10^{20}$ protons-on-target data set taken from 2005 - 2012. By searching for oscillations driven by a large mass splitting, MINOS is sensitive to the existence of sterile neutrinos through any energy dependent deviations using a charged current sample, as well as looking at any relative deficit between neutral current events between the far and near detectors. This document will discuss the novel analysis that enabled a search for sterile neutrinos setting a limit in the previously unexplored regions in the parameter space $\\{\\Delta m^{2}_{41}, \\sin^2\\theta_{24}\\}$. The results presented can be compared to the parameter space suggested by LSND and MiniBooNE and complements other previous experimental searches for sterile neutrinos in the electron neutrino appearance channel.

  5. Neutrinos

    CERN Multimedia

    CERN. Geneva

    2004-01-01

    The Standard Model predicts that the neutrinos are massless and do not mix. Generic extensions of the Standard Model predict that neutrinos are massive (but, very likely, much lighter than the charged fermions). Therefore, the search for neutrino masses and mixing tests the Standard Model and probes new phasics. Measurements of various features of the fluxes of atmospheric, solar and, more recently, reactor neutrinos have provided evidence for neutrino oscillations and therefore for neutrino masses and mixing. These results have significant theoretical implications: new physics exists, and its scale can be estimated. There are interesting lessons for grand unified theories and for models of extra dimensions. The measured neutrino flavor parameters pose a challenge to flavor models.

  6. Search for νμ→ντ neutrino oscillations in the τ-→e-ν-bareντ decay channel in the Nomad experiment at CERN

    International Nuclear Information System (INIS)

    Popov, B.A.

    1998-05-01

    This work has been done in the framework of the NOMAD experiment at CERN. It is devoted to the ν μ → ν τ oscillation search in the τ - → e - ν-bar e ν τ decay channel. After a brief reminder on the neutrino properties and a short review of the experimental searches for neutrino oscillations, the description of the NOMAD experiment is given. The event reconstruction in the NOMAD experiment is presented with a special emphasis put on the electron identification and reconstruction. The track model used for the charged track reconstruction is described in details. The algorithm developed to treat electron trajectories in the NOMAD setup based on the sub-detector matching technique and the breakpoint search algorithm is presented. The quality of the reconstruction of the kinematics of neutrino interactions is illustrated. It is shown that the currently used detector simulation program cannot reproduce precisely the behaviour of the hadronic jet observed in the NOMAD real data especially in the plane perpendicular to the incoming neutrino direction. To overcome this problem simulations based on the real data are used whenever possible. The method based on the likelihood ratio is developed to discriminate a signal from a background. A selection of ν e CC candidates from the NOMAD '96 data set is performed using this technique. 1842 events are extracted with a selection efficiency of (38.5 ± 0.5%) while the background contamination is estimated to be less than 0.5%. This number of events is compatible with our expectations: 1891 ± 25(stat)± 95(syst). No sign of possible ν μ → ν e oscillation signal corresponding to the LSND solution in the large Δm 2 region is observed in the NOMAD data. Finally, the preliminary analysis of the ν μ → ν τ oscillation search in the τ - → e - ν-bar e ν τ decay channel using the data collected during the '96 run is presented. It is shown that currently the contribution of this decay channel to the sensitivity

  7. Neutrinos: from the Workshop to the Factory

    CERN Multimedia

    2001-01-01

    Over the next 5 years much work will be done to reach a theoretical and practical description of a neutrino factory. How could this project turn out to be an interesting future option for CERN? Neutrino beams travelling from CERN to the Canary Islands? And to the Svalbard archipelago in Norway? Or even to the Pyhaesalmi Mine in Finland? Why neutrinos? And why so far? The answers provide one of CERN's next challenging options: the construction of a high-energy muon storage ring to provide neutrino beams. This project, nicknamed 'neutrino factory', now figures in CERN's middle term plan as a recognized and supported research and development project. International collaborations, with other European laboratories and also with America and Japan, are now being set up. Long baseline locations for neutrino oscillations studies at a CERN based neutrino factory. Early in its history, LEP established that there exist just three kinds of light neutrinos, those associated with the electron, muon, and tau leptons. For a...

  8. 7Be solar neutrino measurement with KamLAND

    Science.gov (United States)

    Gando, A.; Gando, Y.; Hanakago, H.; Ikeda, H.; Inoue, K.; Ishidoshiro, K.; Ishikawa, H.; Kishimoto, Y.; Koga, M.; Matsuda, R.; Matsuda, S.; Mitsui, T.; Motoki, D.; Nakajima, K.; Nakamura, K.; Obata, A.; Oki, A.; Oki, Y.; Otani, M.; Shimizu, I.; Shirai, J.; Suzuki, A.; Tamae, K.; Ueshima, K.; Watanabe, H.; Xu, B. D.; Yamada, S.; Yamauchi, Y.; Yoshida, H.; Kozlov, A.; Takemoto, Y.; Yoshida, S.; Grant, C.; Keefer, G.; McKee, D. W.; Piepke, A.; Banks, T. I.; Bloxham, T.; Freedman, S. J.; Fujikawa, B. K.; Han, K.; Hsu, L.; Ichimura, K.; Murayama, H.; O'Donnell, T.; Steiner, H. M.; Winslow, L. A.; Dwyer, D.; Mauger, C.; McKeown, R. D.; Zhang, C.; Berger, B. E.; Lane, C. E.; Maricic, J.; Miletic, T.; Learned, J. G.; Sakai, M.; Horton-Smith, G. A.; Tang, A.; Downum, K. E.; Tolich, K.; Efremenko, Y.; Kamyshkov, Y.; Perevozchikov, O.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Detwiler, J. A.; Enomoto, S.; Heeger, K.; Decowski, M. P.; KamLAND Collaboration

    2015-11-01

    We report a measurement of the neutrino-electron elastic scattering rate of 862 keV 7Be solar neutrinos based on a 165.4 kt d exposure of KamLAND. The observed rate is 582 ±94 (kt d)-1, which corresponds to an 862-keV 7Be solar neutrino flux of (3.26 ±0.52 ) ×109cm-2s-1 , assuming a pure electron-flavor flux. Comparing this flux with the standard solar model prediction and further assuming three-flavor mixing, a νe survival probability of 0.66 ±0.15 is determined from the KamLAND data. Utilizing a global three-flavor oscillation analysis, we obtain a total 7Be solar neutrino flux of (5.82 ±1.02 ) ×109cm-2s-1 , which is consistent with the standard solar model predictions.

  9. Precision Measurement of the Be7 Solar Neutrino Interaction Rate in Borexino

    Science.gov (United States)

    Bellini, G.; Benziger, J.; Bick, D.; Bonetti, S.; Bonfini, G.; Buizza Avanzini, M.; Caccianiga, B.; Cadonati, L.; Calaprice, F.; Carraro, C.; Cavalcante, P.; Chavarria, A.; D'Angelo, D.; Davini, S.; Derbin, A.; Etenko, A.; Fomenko, K.; Franco, D.; Galbiati, C.; Gazzana, S.; Ghiano, C.; Giammarchi, M.; Goeger-Neff, M.; Goretti, A.; Grandi, L.; Guardincerri, E.; Hardy, S.; Ianni, Aldo; Ianni, Andrea; Kobychev, V.; Korablev, D.; Korga, G.; Koshio, Y.; Kryn, D.; Laubenstein, M.; Lewke, T.; Litvinovich, E.; Loer, B.; Lombardi, F.; Lombardi, P.; Ludhova, L.; Machulin, I.; Manecki, S.; Maneschg, W.; Manuzio, G.; Meindl, Q.; Meroni, E.; Miramonti, L.; Misiaszek, M.; Montanari, D.; Mosteiro, P.; Muratova, V.; Oberauer, L.; Obolensky, M.; Ortica, F.; Pallavicini, M.; Papp, L.; Peña-Garay, C.; Perasso, L.; Perasso, S.; Pocar, A.; Raghavan, R. S.; Ranucci, G.; Razeto, A.; Re, A.; Romani, A.; Sabelnikov, A.; 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.

    2011-09-01

    The rate of neutrino-electron elastic scattering interactions from 862 keV Be7 solar neutrinos in Borexino is determined to be 46.0±1.5(stat)-1.6+1.5(syst)counts/(day·100ton). This corresponds to a νe-equivalent Be7 solar neutrino flux of (3.10±0.15)×109cm-2s-1 and, under the assumption of νe transition to other active neutrino flavours, yields an electron neutrino survival probability of 0.51±0.07 at 862 keV. The no flavor change hypothesis is ruled out at 5.0σ. A global solar neutrino analysis with free fluxes determines Φpp=6.06-0.06+0.02×1010cm-2s-1 and ΦCNOMikheyev-Smirnov-Wolfenstein large mixing angle neutrino oscillation model is experimentally tested at low energy.

  10. nuSTORM - Neutrinos from STORed Muons: Proposal to the Fermilab PAC

    CERN Document Server

    Adey, D.; Ankenbrandt, C.M.; Asfandiyarov, R.; Back, J.J.; Barker, G.; Baussan, E.; Bayes, R.; Bhadra, S.; Blackmore, V.; Blondel, A.; Bogacz, S.A.; Booth, C.; Boyd, S.B.; Bravar, A.; Brice, S.J.; Bross, A.D.; Cadoux, F.; Cease, H.; Cervera, A.; Cobb, J.; Colling, D.; Coloma, P.; Coney, L.; Dobbs, A.; Dobson, J.; Donini, A.; Dornan, P.; Dracos, M.; Dufour, F.; Edgecock, R.; Evans, J.; Geelhoed, M.; George, M.A.; Ghosh, T.; Gomez-Cadenas, J.J.; de Gouvea, A.; Haesler, A.; Hanson, G.; Harrison, P.F.; Hartz, M.; Hernandez, P.; Hernando Morata, J.A.; Hodgson, P.; Huber, P.; Izmaylov, A.; Karadzhov, Y.; Kobilarcik, T.; Kopp, J.; Kormos, L.; Korzenev, A.; Kuno, Y.; Kurup, A.; Kyberd, P.; Lagrange, J.B.; Laing, A.; Liu, A.; Link, J.M.; Long, K.; Mahn, K.; Mariani, C.; Martin, C.; Martin, J.; McCauley, N.; McDonald, K.T.; Mena, O.; Mishra, S.R.; Mokhov, N.; Morfin, J.; Mori, Y.; Murray, W.; Neuffer, D.; Nichol, R.; Noah, E.; Parke, S.; Palmer, M.A.; Pascoli, S.; Pasternak, J.; Popovic, M.; Ratoff, P.; Ravonel, M.; Rayner, M.; Ricciardi, S.; Rogers, C.; Rubinov, P.; Santos, E.; Sato, A.; Sen, T.; Scantamburlo, E.; Sedgbeer, J.K.; Smith, D.R.; Smith, P.J.; Sobczyk, J.T.; Soby, L.; Soler, F.J.P.; Soldner-Rembold, S.; Sorel, M.; Snopok, P.; Stamoulis, P.; Stanco, L.; Striganov, S.; Tanaka, H.A.; Taylor, I.J.; Touramanis, C.; Tunnell, C.D.; Uchida, Y.; Vassilopoulos, N.; Wascko, M.O.; Weber, A.; Wilking, M.J.; Wildner, E.; Winter, W.; Yang, U.K.

    2013-01-01

    The nuSTORM facility has been designed to deliver beams of electron neutrinos and muon neutrinos (and their anti-particles) from the decay of a stored muon beam with a central momentum of 3.8 GeV/c and a momentum acceptance of 10%. The facility is unique in that it will: 1. Allow searches for sterile neutrinos of exquisite sensitivity to be carried out; 2. Serve future long- and short-baseline neutrino-oscillation programs by providing definitive measurements of electron neutrino and muon neutrino scattering cross sections off nuclei with percent-level precision; and 3. Constitutes the crucial first step in the development of muon accelerators as a powerful new technique for particle physics. The document describes the facility in detail and demonstrates its physics capabilities. This document was submitted to the Fermilab Physics Advisory Committee in consideration for Stage I approval.

  11. Two Light Sterile Neutrinos that Mix Maximally with Each Other and Moderately with Three Active Neutrinos

    International Nuclear Information System (INIS)

    Krolikowski, W.

    2004-01-01

    Since the 3+1 neutrino models with one light sterile neutrino turn out to be not very effective, at least two light sterile neutrinos may be needed to reconcile the solar and atmospheric neutrino experiments with the LSND result, if this is confirmed by the ongoing MiniBooNE experiment (and when the CPT invariance is assumed to hold for neutrino oscillations). We present an attractive 3+2 neutrino model, where two light sterile neutrinos mix maximally with each other, in analogy to the observed maximal mixing of muon and tauon active neutrinos. But, while the mixing of ν e and (ν μ - ν τ )/√2 is observed as large (though not maximal), the mixing of ν e with the corresponding combination of two light sterile neutrinos is expected to be only moderate because of the reported smallness of LSND oscillation amplitude. The presented model turns out, however, not to be more effective in explaining the hypothetic LSND result than the simplest 3+1 neutrino model. On the other hand, in the considered 3+2 model, the deviations from conventional oscillations of three active neutrinos appear to be minimal within a larger class of 3+2 models. (author)

  12. Possibility of measuring Adler angles in charged current single pion neutrino-nucleus interactions

    Science.gov (United States)

    Sánchez, F.

    2016-05-01

    Uncertainties in modeling neutrino-nucleus interactions are a major contribution to systematic errors in long-baseline neutrino oscillation experiments. Accurate modeling of neutrino interactions requires additional experimental observables such as the Adler angles which carry information about the polarization of the Δ resonance and the interference with nonresonant single pion production. The Adler angles were measured with limited statistics in bubble chamber neutrino experiments as well as in electron-proton scattering experiments. We discuss the viability of measuring these angles in neutrino interactions with nuclei.

  13. The issue of mass generation: the search for the Higgs boson in the D0 experiment at the proton-antiproton collider of Fermilab and the measurement of neutrino oscillation with OPERA

    International Nuclear Information System (INIS)

    Lucotte, A.

    2004-09-01

    The first part is dedicated to the theoretical aspects of the mechanism of mass generation in the standard model. The implications of this mechanism in the experimental field concerning the Higgs boson search and neutrinos are detailed. The second part presents the D0 experiment at the Tevatron (Fermilab) and describes in a detailed way the forward pre-shower (FPS) that is a sub-detector of D0 whose aim is to identify the electrons. FPS has required a specific triggering system linked to a data acquisition line. The third part is devoted to the Opera experiment that is planned to operate in 2006. The purpose of this experiment is to confirm the oscillations of muon neutrinos and tau neutrinos through the direct detection of a tau lepton in the pure beam of muon neutrinos produced in CERN. The author describes his contribution to the design and testing of the front-end read electronics of the Opera scintillator tracker. (A.C.)

  14. Status of non-standard neutrino interactions

    International Nuclear Information System (INIS)

    Ohlsson, Tommy

    2013-01-01

    The phenomenon of neutrino oscillations has been established as the leading mechanism behind neutrino flavor transitions, providing solid experimental evidence that neutrinos are massive and lepton flavors are mixed. Here we review sub-leading effects in neutrino flavor transitions known as non-standard neutrino interactions (NSIs), which is currently the most explored description for effects beyond the standard paradigm of neutrino oscillations. In particular, we report on the phenomenology of NSIs and their experimental and phenomenological bounds as well as an outlook for future sensitivity and discovery reach. (review article)

  15. Gif 2011 school: neutrinos. Slides of the presentations

    International Nuclear Information System (INIS)

    Smirnov, A.; Pascoli, S.; Piquemal, F.; Lasserre, T.; Kouchner, A.; Patzak, T.; Lavignac, S.; Volpe, C.; Katsanevas, S.; Rubbia, A.

    2012-01-01

    This document gathers the slides of the lectures given at the GIF 2011 school. These lectures were pedagogical reviews of both theoretical and experimental physics around neutrino issues. There were 9 lectures: 1) the origin of the neutrino mass, 2) theory of neutrino oscillations, 3) measuring the neutrino mass, 4) measuring the neutrino oscillation parameters, 5) astronomy with neutrinos, 6) the story of the neutrino, 7) neutrinos beyond the standard model, 8) neutrinos in cosmology, and 9) future experiments. (A.C.)

  16. Angular distribution in electron-neutrino scattering and the anomalous magnetic moment of the neutrino

    International Nuclear Information System (INIS)

    Barut, A.O.; Aydin, Z.Z.

    1988-08-01

    Some implications of the anomalous magnetic moment a υ of the neutrino are discussed, in particular the differential cross-sections of the electron-neutrino (antineutrino) scattering, (υ e and υ μ ), of the magnetic model is compared with the standard model in order to set better limits on a υ . (author). 18 refs, 2 figs

  17. Studies of neutrino properties at nuclear reactors. Present status and future

    CERN Document Server

    Mikaehlyan, L A

    2002-01-01

    The state and prospects of the experiments at nuclear reactors on the search for the neutrino mass, mixing and magnetic moments, identification whereof would prove the existence of events behind the standard model limits, are considered. The CHOOZ experiment established with complete determination, that the nu sub e -> nu sub x channel is not predominant in the atmospheric neutrino oscillations. The KamLAND may become the first among the experiments with the neutrino earth sources, wherein the oscillation effect will be determined; the contributions of the m sub 1 and m sub 2 masses to the electron neutrino is established and solution of the solar neutrino problem is found. The Kr2Det experiment with its high sensitivity to the small mixing angles may identify the contribution of the m sub 3 mass to the nu sub e or establish a new more exact limit on its value. These studies rest upon the unprecedented improvement of the reverse beta-decay registration methods

  18. Muon neutrino disappearance at MINOS

    International Nuclear Information System (INIS)

    Armstrong, R.

    2009-01-01

    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 Δm 32 2 = 2.45 +0.12 -0.12 x 10 -3 eV 2 and sin 2 (2θ 32 ) = 1.00 -0.04 +0.00 (> 0.90 at 90% confidence level).

  19. Equation-of-state dependent features in shock-oscillation modulated neutrino and gravitational-wave signals from supernovae

    Science.gov (United States)

    Marek, A.; Janka, H.-T.; Müller, E.

    2009-03-01

    We present two-dimensional (axisymmetric) neutrino-hydrodynamic simulations of the long-time accretion phase of a 15 M_⊙ progenitor star after core bounce and before the launch of a supernova explosion, when non-radial hydrodynamic instabilities like convection occur in different regions of the collapsing stellar core and the standing accretion shock instability (SASI) leads to large-amplitude oscillations of the stalled shock with a period of tens of milliseconds. Our simulations were performed with the Prometheus-Vertex code, which includes a multi-flavor, energy-dependent neutrino transport scheme and employs an effective relativistic gravitational potential. Testing the influence of a stiff and a soft equation of state for hot neutron star matter, we find that the non-radial mass motions in the supernova core impose a time variability on the neutrino and gravitational-wave signals with larger amplitudes, as well as higher frequencies in the case of a more compact nascent neutron star. After the prompt shock-breakout burst of electron neutrinos, a more compact accreting remnant produces higher neutrino luminosities and higher mean neutrino energies. The observable neutrino emission in the SASI sloshing direction exhibits a modulation of several ten percent in the luminosities and around 1 MeV in the mean energies with most power at typical SASI frequencies between roughly 20 and 100 Hz. The modulation is caused by quasi-periodic variations in the mass accretion rate of the neutron star in each hemisphere. At times later than ~50-100 ms after bounce, the gravitational-wave amplitude is dominated by the growing low-frequency (⪉200 Hz) signal associated with anisotropic neutrino emission. A high-frequency wave signal results from nonradial gas flows in the outer layers of the anisotropically accreting neutron star. Right after bounce such nonradial mass motions occur due to prompt post-shock convection in both considered cases and contribute mostly to the early

  20. Sterile Neutrino Search in the NOvA Far Detector

    Energy Technology Data Exchange (ETDEWEB)

    Edayath, Sijith [Cochin U.; Aurisano, Adam [Cincinnati U.; Sousa, Alexandre [Cincinnati U.; Davies, Gavin [Indiana U.; Suter, Louise [Fermilab; Yang, Shaokai [Cincinnati U.

    2017-10-03

    The majority of neutrino oscillation experiments have obtained evidence for neutrino oscillations that are compatible with the three-flavor model. Explaining anomalous results from short-baseline experiments, such as LSND and MiniBooNE, in terms of neutrino oscillations requires the existence of sterile neutrinos. The search for sterile neutrino mixing conducted in NOvA uses a long baseline of 810 km between Near Detector (ND) at Fermilab and Far Detector (FD) in Minnesota. The signal for sterile neutrino oscillations is a deficit of neutral-current neutrino interactions at the FD with respect to the ND prediction. In this document, We will present the analysis improvements that we are implementing for future NC sterile neutrino searches with NOvA. These include: improved modelling of our detector response; the inclusion of NC 2p2h interaction modelling; implementing a better energy reconstruction techniques; and including possible oscillation due to sterile neutrinos in the ND . This improvements enable us to do a simultaneous ND-FD shape fit of the NC energy spectrum covering a wider sterile mass range than previous analyses.

  1. Gravity wave and neutrino bursts from stellar collapse: A sensitive test of neutrino masses

    International Nuclear Information System (INIS)

    Arnaud, N.; Barsuglia, M.; Bizouard, M.A.; Cavalier, F.; Davier, M.; Hello, P.; Pradier, T.

    2002-01-01

    New methods are proposed with the goal to determine absolute neutrino masses from the simultaneous observation of the bursts of neutrinos and gravitational waves emitted during a stellar collapse. It is shown that the neutronization electron neutrino flash and the maximum amplitude of the gravitational wave signal are tightly synchronized with the bounce occurring at the end of the core collapse on a time scale better than 1 ms. The existing underground neutrino detectors (SuperKamiokande, SNO,...) and the gravity wave antennas soon to operate (LIGO, VIRGO,...) are well matched in their performance for detecting galactic supernovae and for making use of the proposed approach. Several methods are described, which apply to the different scenarios depending on neutrino mixing. Given the present knowledge on neutrino oscillations, the methods proposed are sensitive to a mass range where neutrinos would essentially be mass degenerate. The 95% C.L. upper limit which can be achieved varies from 0.75 eV/c 2 for large ν e survival probabilities to 1.1 eV/c 2 when in practice all ν e 's convert into ν μ 's or ν τ 's. The sensitivity is nearly independent of the supernova distance

  2. The liquid scintillator neutrino detector and LAMPF neutrino source

    Energy Technology Data Exchange (ETDEWEB)

    Athanassopoulos, C.; Auerbach, L.B.; Bauer, D.; Bolton, R.D.; Burman, R.L.; Cohen, I.; Caldwell, D.O.; Dieterle, B.D.; Donahue, J.B.; Eisner, A.M.; Fazely, A.; Federspiel, F.J.; Garvey, G.T.; Gray, M.; Gunasingha, R.M.; Highland, V.; Imlay, R.; Johnston, K.; Kim, H.J.; Louis, W.C.; Lu, A.; Margulies, J.; Mills, G.B.; McIlhany, K.; Metcalf, W.; Reeder, R.A.; Sandberg, V.; Schillaci, M.; Smith, D.; Stancu, I.; Strossman, W.; Tayloe, R.; VanDalen, G.J.; Vernon, W.; Wang, Y.-X.; White, D.H.; Whitehouse, D.; Works, D.; Xiao, Y.; Yellin, S. [California Univ., Riverside, CA (United States)]|[University of California, San Diego, CA 92093 (United States)]|[University of California, Santa Barbara, CA 93106 (United States)]|[University of California, Intercampus Institute for Research at Particle Accelerators, Stanford, CA 94309 (United States)]|[Embry Riddle Aeronautical University, Prescott, AZ 86301 (United States)]|[Linfield College, McMinnville, OR 97128 (United States)]|[Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)]|[Louisiana State University, Baton Rouge, LA 70803 (United States)]|[Louisiana Tech University, Ruston, LA 71272 (United States)]|[University of New Mexico, Albuquerque, NM 87131 (United States)]|[Southern University, Baton Rouge, LA 70813 (United States)]|[Temple University, Philadelphia, PA 19122 (United States)

    1997-03-21

    A search for neutrino oscillations of the type {nu}{sub {mu}}{yields}{nu}{sub e} has been conducted at the Los Alamos Meson Physics Facility using {nu}{sub {mu}} from muon decay at rest. Evidence for this transition has been reported previously. This paper discusses in detail the experimental setup, detector operation and neutrino source, including aspects relevant to oscillation searches in the muon decay-at-rest and pion decay in flight channels. (orig.).

  3. Sub aqueous electronics of neutrino detector; Podvodnaya ehlektronika nejtrinnogo detektora

    Energy Technology Data Exchange (ETDEWEB)

    Borisovets, B A; Donskikh, L A; Klabukov, A M [and others

    1996-12-31

    Paper describes the systems of measuring electronics of NT-200 neutrino detector designed to carry out investigations in the field of neutrino astrophysics. Correlation measuring electronics unit are presented by two two-level discriminators and coincidence circuit is studied. 6-channel unit of electronic chain covering time-code number recording is designed for data communication into the computer. detector calibration mode is described. 3 refs.

  4. Flavor ratios of extragalactic neutrinos and neutrino shortcuts in extra dimensions

    Energy Technology Data Exchange (ETDEWEB)

    Aeikens, Elke; Päs, Heinrich [Fakultät für Physik, Technische Universität Dortmund,44221 Dortmund (Germany); Pakvasa, Sandip [Department of Physics & Astronomy, University of Hawaii,Honolulu, HI 96822 (United States); Sicking, Philipp [Fakultät für Physik, Technische Universität Dortmund,44221 Dortmund (Germany)

    2015-10-02

    The recent measurement of high energy extragalactic neutrinos by the IceCube Collaboration has opened a new window to probe non-standard neutrino properties. Among other effects, sterile neutrino altered dispersion relations (ADRs) due to shortcuts in an extra dimension can significantly affect astrophysical flavor ratios. We discuss two limiting cases of this effect, first active-sterile neutrino oscillations with a constant ADR potential and second an MSW-like resonant conversion arising from geodesics oscillating around the brane in an asymmetrically warped extra dimension. We demonstrate that the second case has the potential to suppress significantly the flux of specific flavors such as ν{sub μ} or ν{sub τ} at high energies.

  5. Flavor ratios of extragalactic neutrinos and neutrino shortcuts in extra dimensions

    Energy Technology Data Exchange (ETDEWEB)

    Aeikens, Elke; Päs, Heinrich; Sicking, Philipp [Fakultät für Physik, Technische Universität Dortmund, 44221 Dortmund (Germany); Pakvasa, Sandip, E-mail: elke.aeikens@tu-dortmund.de, E-mail: heinrich.paes@tu-dortmund.de, E-mail: pakvasa@phys.hawaii.edu, E-mail: philipp.sicking@tu-dortmund.de [Department of Physics and Astronomy, University of Hawaii, Honolulu, HI 96822 (United States)

    2015-10-01

    The recent measurement of high energy extragalactic neutrinos by the IceCube Collaboration has opened a new window to probe non-standard neutrino properties. Among other effects, sterile neutrino altered dispersion relations (ADRs) due to shortcuts in an extra dimension can significantly affect astrophysical flavor ratios. We discuss two limiting cases of this effect, first active-sterile neutrino oscillations with a constant ADR potential and second an MSW-like resonant conversion arising from geodesics oscillating around the brane in an asymmetrically warped extra dimension. We demonstrate that the second case has the potential to suppress significantly the flux of specific flavors such as ν{sub μ} or ν{sub τ} at high energies.

  6. Neutral-current detection in the Sudbury Neutrino Observatory

    International Nuclear Information System (INIS)

    Bowles, T.J.; Doe, P.J.; Fowler, M.M.; Hime, A.; Robertson, R.G.H.; Thornewell, P.M.; Wilhelmy, J.B.; Wilkerson, J.F.; Wouters, J.M.

    1993-01-01

    The Sudbury Neutrino Observatory (SNO) will have the capability of detecting all active species of neutrinos with energies greater than 2.2 MeV by the neutral-current disintegration of deuterium. The comparison of this rate with the rate of inverse beta decay of the deuteron will yield a nearly model-independent answer to the question of whether electron neutrinos from the sun oscillate into mu or tau neutrinos. The signal of a neutral-current interaction is the liberation of a free neutron in the heavy-water detector, and we discuss a technique employing 3 He proportional counters for registering these neutrons, particularly from the standpoint of the ultra-low backgrounds needed

  7. Do high-energy neutrinos travel faster than photons in a discrete space-time?

    Energy Technology Data Exchange (ETDEWEB)

    Xue Shesheng, E-mail: xue@icra.it [ICRANeT, Piazzale della Repubblica, 10-65122, Pescara, Physics Department, University of Rome ' ' La Sapienza' ' , Rome (Italy)

    2011-12-06

    The recent OPERA measurement of high-energy neutrino velocity, once independently verified, implies new physics in the neutrino sector. We revisit the theoretical inconsistency of the fundamental high-energy cutoff attributing to quantum gravity with the parity-violating gauge symmetry of local quantum field theory describing neutrinos. This inconsistency suggests high-dimension operators of neutrino interactions. Based on these studies, we try to view the OPERA result, high-energy neutrino oscillations and indicate to observe the restoration of parity conservation by measuring the asymmetry of high-energy neutrinos colliding with left- and right-handed polarized electrons.

  8. Neutrino Physics

    CERN Document Server

    Barenboim, G.

    2014-12-10

    The Standard Model has been incredibly successful in predicting the outcome of almost all the experiments done up so far. In it, neutrinos are mass-less. However, in recent years we have accumulated evidence pointing to tiny masses for the neutrinos (as compared to the charged leptons). These masses allow neutrinos to change their flavour and oscillate. In these lectures I review the properties of neutrinos in and beyond the Standard Model.

  9. Latest Results from the Daya Bay Reactor Neutrino Experiment

    CERN Multimedia

    CERN. Geneva

    2014-01-01

    Among all the fundamental particles that have been experimentally observed, neutrinos remain one of the least understood. The Daya Bay Reactor Neutrino Experiment in China consists of eight identical detectors placed underground at different baselines from three groups of nuclear reactors, a configuration that is ideally suited for studying the properties of these elusive particles. This talk will present three sets of results that have just recently been released by the Daya Bay Collaboration: (i) a precision measurement of the oscillation parameters that drive the disappearance of electron antineutrinos at short baselines, (ii) a search for sterile neutrino mixing, and (iii) a high-statistics determination of the absolute flux and spectrum of reactor-produced electron antineutrinos. All of these results extend the limits of our knowledge in their respective areas and thus shed new light on neutrinos and the physics that surround them.

  10. Interaction of electron neutrino with LSD detector

    Science.gov (United States)

    Ryazhskaya, O. G.; Semenov, S. V.

    2016-06-01

    The interaction of electron neutrino flux, originating in the rotational collapse mechanism on the first stage of Supernova burst, with the LSD detector components, such as 56Fe (a large amount of this metal is included in as shielding material) and liquid scintillator barNnH2n+2, is being investigated. Both charged and neutral channels of neutrino reaction with 12barN and 56Fe are considered. Experimental data, giving the possibility to extract information for nuclear matrix elements calculation are used. The number of signals, produced in LSD by the neutrino pulse of Supernova 1987A is determined. The obtained results are in good agreement with experimental data.

  11. Reconstruction et analyse des gerbes électromagnétiques dans l'expérience OPERA et étude des oscillations neutrino avec détection d'électrons

    CERN Document Server

    Brunet, Florian

    An international program is ongoing to measure the neutrino oscillation phenomenon and to determine the neutrino mixing matrix (MNSP) parameters. OPERA is a long-baseline neutrino experiment located at the Gran Sasso Laboratory in Italy, 730~km from CERN, downstream in the CNGS neutrino beam. The OPERA experiment is designed and optimised for a direct appearance search of νµ → ντ oscillations. It can also detect the νµ → νe oscillation driven by sin(2θ13)2 , where θ13 is the last mixing angle finally measured by the Daya Bay, RENO, and Double Chooz experiments in 2012. To observe the presence of ντ interactions in the beam, the OPERA detector is composed of calorimetric targets made of a modular structure called the "brick": a sandwich of lead plates interspaced with emulsion layers. The latter allows reconstructing tracks of charged particles produced in the neutrino interactions with a micrometric resolution. The search for the νµ → νe oscillation signal is based on the capability of ide...

  12. Search for neutrino oscillations {nu}{sub {mu}}{yields}{nu}{sub {tau}} in the decay channel: {tau}{yields}{rho} of the NOMAD experiment; Recherche d'oscillations de neutrinos {nu}{sub {mu}}{yields}{nu}{sub {tau}} dans le canal de desintegration {tau}{yields}{rho} aupres de l'experience NOMAD au Cern

    Energy Technology Data Exchange (ETDEWEB)

    Besson, N

    1999-10-01

    The purpose of the NOMAD experiment is to find the oscillations of muon-neutrinos into tau-neutrinos by detecting the presence of tau-neutrinos in a beam made up essentially of muon-neutrinos. The first part of this thesis is dedicated to neutrinos, to the open questions in neutrino physics and gives the elements necessary to understand the oscillation phenomenon. The second part presents the principle on which is based the NOMAD experiment and the NOMAD detector is described. NOMAD detector is made up of 49 big drift chambers. The data collected allow the reconstruction of interaction vertex, of tracks of charged particles and give accurate values of energies and impulses involved in the process. A very important point is the alignment of the chambers and their efficiency. This thesis is a contribution to the improvement of reconstruction methods. The aim of NOMAD detector is to reveal the presence of tau-neutrino by detecting the decay products of the {tau}{sup -} issued from the current charged interaction of the tau-neutrino with the target. 5 channels of the {tau}{sup -} decay are opened to NOMAD detector but the hadronic channel: {tau}{sup -} {yields} {rho}{sup -} is the most interesting because of its high branching ratio (25.3%). The fourth part describes the analysis methods which are based on various decay topologies of {rho}. (A.C.)

  13. Extracting limits for the difuse non-electron neutrino flux from SNO data

    Energy Technology Data Exchange (ETDEWEB)

    Miguez, B.S.R.; Kemp, E.; Peres, O.L.G. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Inst. de Fisica Gleb Wataghin

    2009-07-01

    Full text. There is a prediction of a diffuse neutrino flux yield from the time integration of all supernova already exploded in the past governed by stellar formation and supernovae occurrence rates. The spectral characteristics of these neutrinos differ from those from recent supernovae mainly in two features: the reduction in their fluxes and their energy 'redshift' due the expansion of the universe. Thus, despite the fact that one single supernova is a transient state, their cumulative effect produces a steady flux of diffuse neutrinos everywhere in universe. These neutrinos have never been observed before. Only upper limits on their fluxes have been reported by the collaborations operating neutrino telescopes. Recently the SNO experiment have made an analysis where the total flux of diffuse electron neutrinos has an upper limit of phi{sub e} <= 61-93 cm{sup -2} s{sup -1}, depending on a specific supernova model. At the present, the best limit for the diffuse flux of non-electron neutrinos is phi{sub x} <= 10{sub 4} cm{sup -2} s{sup -1}, resulted from an analysis of the Super-Kamiokande data. In this work we have extended the SNO analysis including the elastic scattering on electrons via neutral current interactions to extract information on diffuse flux of the non-electron neutrino flavours (i.e. muon and tauon neutrinos). We make a comparison among our results and others from different experiments (LVD, SK, LSD). (author)

  14. Neutrino magnetic moments and the solar neutrino problem

    Energy Technology Data Exchange (ETDEWEB)

    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.

  15. Neutrino magnetic moments and the solar neutrino problem

    International Nuclear Information System (INIS)

    Akhmedov, E.Kh.; Valencia Univ.

    1994-01-01

    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 2θ 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 ν e 's

  16. Prospects for very large, sensitive water Cherenkov detectors for proton decay and neutrino oscillations search

    International Nuclear Information System (INIS)

    Cline, D.B.

    1982-01-01

    We discuss the possibility of constructing large water Cherenkov detectors with mass 10 5 to 10 6 tons that would be sensitive to a few hundred MeV - few GeV energy release. The 10 5 ton detector would be suitable for a search for certain proton decay modes whereas the 10 6 ton detector would act as an active shield for the proton decay detector and as a nu/sub e/, nu/sub μ/ and possibly nu/sub tau/ interaction detector. The neutrino physics would include a sensitive search for neutrino oscillations using atmospheric neutrinos. The location of this detector could be in the deep ocean near Hawaii or in a deep trench between Cuba and Haiti or perhaps deep lakes like Superior or Baikal if flexible containers are used

  17. PINGU sensitivity to neutrino mass hierarchy

    International Nuclear Information System (INIS)

    Groß, Andreas

    2014-01-01

    Determination of the neutrino mass hierarchy (NMH) is among the most fundamental questions in particle physics. Recent measurements of 1) a large mixing angle between the first and the third neutrino mass eigenstates and 2) the first observation of atmospheric neutrino oscillations at tens of GeV with neutrino telescopes, open the intriguing new possibility to exploit matter effects in neutrino oscillation to determine the neutrino mass hierarchy. A further extension of IceCube/DeepCore called PINGU (Precision IceCube Next Generation Upgrade) has been recently envisioned with the ultimate goal to measure neutrino mass hierarchy. PINGU would consist of additional IceCube-like strings of detectors deployed in the deepest and cleanest ice in the center of IceCube. More densely deployed instrumentation would provide a threshold substantially below 10 GeV and enhance the sensitivity to the mass hierarchy signal in atmospheric neutrinos. Here we discuss an estimate of the PINGU sensitivity to the mass hierarchy determined using an approximation with an Asimov dataset and an oscillation parameter fit

  18. Search for sterile neutrinos with IceCube DeepCore

    Energy Technology Data Exchange (ETDEWEB)

    Terliuk, Andrii [DESY, Platanenallee 6, 15738 Zeuthen (Germany); Collaboration: IceCube-Collaboration

    2016-07-01

    The DeepCore detector is a sub-array of the IceCube Neutrino Observatory that lowers the energy threshold for neutrino detection down to approximately 10 GeV. DeepCore is used for a variety of studies including atmospheric neutrino oscillations. The standard three-neutrino oscillation paradigm is tested using the DeepCore detector by searching for an additional light, sterile neutrino with a mass on the order of 1 eV. Sterile neutrinos do not interact with the ordinary matter, however they can be mixed with the three active neutrino states. Such mixture changes the picture of standard neutrino oscillations for atmospheric neutrinos with energies below 100 GeV. The capabilities of DeepCore detector to measure such sterile neutrino mixing will be presented in this talk.

  19. Hunting for a massive neutrino

    CERN Document Server

    AUTHOR|(CDS)2108802

    1997-01-01

    A great effort is devoted by many groups of physicists all over the world to give an answer to the following question: Is the neutrino massive ? This question has profound implications with particle physics, astrophysics and cosmology, in relation to the so-called Dark Matter puzzle. The neutrino oscillation process, in particular, can only occur if the neutrino is massive. An overview of the neutrino mass measurements, of the oscillation formalism and experiments will be given, also in connection with the present experimental programme at CERN with the two experiments CHORUS and NOMAD.

  20. Analytical approximations for matter effects on CP violation in the accelerator-based neutrino oscillations with E≲1 GeV

    Energy Technology Data Exchange (ETDEWEB)

    Xing, Zhi-zhong [Institute of High Energy Physics, Chinese Academy of Sciences,Beijing 100049 (China); School of Physical Sciences, University of Chinese Academy of Sciences,Beijing 100049 (China); Center for High Energy Physics, Peking University,Beijing 100080 (China); Zhu, Jing-yu [Institute of High Energy Physics, Chinese Academy of Sciences,Beijing 100049 (China)

    2016-07-04

    Given an accelerator-based neutrino experiment with the beam energy E≲1 GeV, we expand the probabilities of ν{sub μ}→ν{sub e} and ν̄{sub μ}→ν̄{sub e} oscillations in matter in terms of two small quantities Δ{sub 21}/Δ{sub 31} and A/Δ{sub 31}, where Δ{sub 21}≡m{sub 2}{sup 2}−m{sub 1}{sup 2} and Δ{sub 31}≡m{sub 3}{sup 2}−m{sub 1}{sup 2} are the neutrino mass-squared differences, and A measures the strength of terrestrial matter effects. Our analytical approximations are numerically more accurate than those made by Freund in this energy region, and thus they are particularly applicable for the study of leptonic CP violation in the low-energy MOMENT, ESSνSM and T2K oscillation experiments. As a by-product, the new analytical approximations help us to easily understand why the matter-corrected Jarlskog parameter J̃ peaks at the resonance energy E{sub ∗}≃0.14 GeV (or 0.12 GeV) for the normal (or inverted) neutrino mass hierarchy, and how the three Dirac unitarity triangles are deformed due to the terrestrial matter contamination. We also affirm that a medium-baseline neutrino oscillation experiment with the beam energy E lying in the E{sub ∗}≲E≲2E{sub ∗} range is capable of exploring leptonic CP violation with little matter-induced suppression.