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1

(L{sub e}-L{sub {mu}-}L{sub {tau}}) discrete symmetry for heavy right-handed neutrinos and degenerate leptogenesis  

Science Conference Proceedings (OSTI)

The degenerate leptogenesis is studied when the degeneracy in two of the heavy right-handed neutrinos [the third one is irrelevant if {mu}-{tau} symmetry is assumed] is due to L{identical_to}(L{sub e}-L{sub {mu}-}L{sub {tau}}) discrete symmetry. It is shown that a sizable leptogenesis asymmetry ({epsilon}{>=}10{sup -6}) is possible. The level of degeneracy required also predicts the Majorana phase needed for the asymmetry and this prediction is testable since it is the same phase, which appears in the double {beta} decay. Implications of nonzero reactor angle {theta}{sub 13} are discussed. It is shown that the contribution from sin{sup 2{theta}}{sub 13} to the leptogenesis asymmetry parameter may even dominate. An accurate measurement of sin{sup 2{theta}}{sub 13} would have important implications for the mass degeneracy of heavy right-handed neutrinos.

Riazuddin [Centre for Advanced Mathematics and Physics, National University of Sciences and Technology, Rawalpindi (Pakistan) and National Centre for Physics, Quaid-i-Azam University, Islamabad (Pakistan)

2010-05-01T23:59:59.000Z

2

Atmospheric neutrino oscillations and tau neutrinos in ice  

E-Print Network (OSTI)

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

Gerardo Giordano; Olga Mena; Irina Mocioiu

2010-04-20T23:59:59.000Z

3

Tau Neutrino Appearance with a 1000 Megaparsec Baseline  

E-Print Network (OSTI)

A high-energy neutrino telescope, such as the operating AMANDA detector, may detect neutrinos produced in sources, possibly active galactic nuclei or gamma-ray bursts, distant by a thousand megaparsecs. These sources produce mostly nu_e or nu_mu neutrinos. Above 1 PeV, nu_e and nu_mu are absorbed by charged-current interactions in the Earth before reaching the opposite surface. However, the Earth never becomes opaque to nu_tau since the tau^- produced in a charged-current nu_tau interaction decays back into nu_tau before losing significant energy. This preferential penetration of tau neutrinos through the Earth above 10^14 eV provides an experimental signature for neutrino oscillations. The appearance of a nu_tau component would be evident as a flat zenith angle dependence of a source intensity at the highest neutrino energies. Such an angular dependence would indicate nu_tau mixing with a sensitivity to delta-m^2 as low as 10^-17 eV^2, for the farthest sources. In addition, the presence of tau neutrino mixing would provide the opportunity for neutrino astronomy well beyond the PeV cutoff, possibly out to the energies matching those of the highest energy protons observed above 10^20 eV.

Francis Halzen; David Saltzberg

1998-04-21T23:59:59.000Z

4

Tracing Very High Energy Tau Neutrinos from Cosmological Distances in Ice  

E-Print Network (OSTI)

Astrophysical sources of ultrahigh energy neutrinos yield tau neutrino fluxes due to neutrino oscillations. We study in detail the contribution of tau neutrinos with energies above $10^6$ GeV relative to the contribution of the other flavors. We consider several different initial neutrino fluxes and include tau neutrino regeneration in transit through the Earth and energy loss of charged leptons. We discuss signals of tau neutrinos in detectors such as IceCube, RICE and ANITA.

J. Jones; I. Mocioiu; I. Sarcevic; M. H. Reno

2004-08-04T23:59:59.000Z

5

Detecting Tau Neutrino Oscillations at PeV Energies  

E-Print Network (OSTI)

It is suggested that a large deep underocean (or ice) neutrino detector, given the presence of significant numbers of neutrinos in the PeV energy range as predicted by various models of Active Galactic Nuclei, can make unique measurements of the properties of neutrinos. It will be possible to observe the existence of the tau neutrino, measure its mixing with other flavors, in fact test the mixing pattern for all three flavors based upon the mixing parameters suggested by the atmospheric and solar neutrino data, and measure the tau neutrino cross section. The key signature is the charged current tau neutrino interaction, which produces a double cascade, one at either end of a lightly radiating track. At a few PeV these cascades would be separated by roughly 100 m, and thus be easily resolvable in next generation DUMAND-like detectors. First examples might be found in detectors presently under construction. Future applications are precise neutrino astronomy and earth tomography. This paper is an expanded version of hep-ph/9405296, for publication.

John G. Learned; Sandip Pakvasa

1994-08-16T23:59:59.000Z

6

Muon and Tau Neutrinos Spectra from Solar Flares  

E-Print Network (OSTI)

Solar neutrino flares and mixing are considered. Most power-full solar flare as the ones occurred on 23th February 1956, September 29th 1989, 28th October and on 2nd-4th November 2003 are sources of cosmic rays, X, gamma and neutrino bursts. These flares took place both on front or in the edge and in the hidden solar disk. The observed and estimated total flare energy should be a source of a prompt secondary neutrino burst originated, by proton-proton-pion production on the sun itself; a more delayed and spread neutrino flux signal arise by the solar charged flare particles reaching the terrestrial atmosphere. Our first estimates of neutrino signals in largest underground detectors hint for few events in correlation with, gamma,radio onser. Our approximated spectra for muons and taus from these rare solar eruption are shown over the most common background. The muon and tau signature is very peculiar and characteristic over electron and anti-electron neutrino fluxes. The rise of muon neutrinos will be detectable above the minimal muon threshold of 113 MeV. The rarest tau appearence will be possible only for hardest solar neutrino energies above 3.471 GeV

D. Fargion; F. Moscato

2004-05-03T23:59:59.000Z

7

The energy spectrum of tau leptons induced by the high energy Earth-skimming neutrinos  

E-Print Network (OSTI)

We present a semi-analytic calculation of the tau-lepton flux emerging from the Earth, induced by the incident high energy neutrinos interacting inside the Earth for $10^{5} \\leq E_{\

J. -J. Tseng; T. -W. Yeh; H. Athar; M. A. Huang; F. -F. Lee; G. -L. Lin

2003-05-27T23:59:59.000Z

8

Study of the tau- ---> 3h- 2h+ tau-neutrino decay  

SciTech Connect

The branching fraction of the {tau}{sup -} {yields} 3h{sup -} 2h{sup +} {nu}{sub {tau}} decay (h = {pi}, K) is measured with the BABAR detector to be (8.56 {+-} 0.05 {+-} 0.42) x 10{sup -4}, where the first error is statistical and the second systematic. The observed structure of this decay is significantly different from the phase space prediction, with the {rho} resonance playing a strong role. The decay {tau}{sup -} {yields} f{sub 1}(1285){pi}{sup -}{nu}{sub {tau}}, with the f{sub 1}(1285) meson decaying to four charged pions, is observed and the branching fraction is measured to be (3.9 {+-} 0.7 {+-} 0.5) x 10{sup -4}.

Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; /Annecy, LAPP; Grauges, E.; /Barcelona, IFAE; Palano, A.; Pappagallo, M.; Pompili, A.; /Bari U. /INFN, Bari; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; /Beijing, Inst. High Energy Phys.; Eigen, G.; Ofte, I.; Stugu, B. /Bergen U. /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /Pisa U. /INFN, Pisa /Prairie View A-M /Princeton U. /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /South Carolina U. /SLAC /Oregon U. /SLAC /SLAC /Stanford U., Phys. Dept. /SUNY, Stony Brook /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Vanderbilt U. /Victoria U. /Warwick U. /Wisconsin U., Madison /Yale U.

2005-05-04T23:59:59.000Z

9

Lepton flavor violation decays with the fourth generation neutrino  

E-Print Network (OSTI)

We investigate the lepton flavor violation decays, $\\tau \\to \\mu\\gamma$, $\\tau \\to e\\gamma$ and $\\mu \\to e\\gamma$, in the framwork of a squential fourth generation model with a heavy fourth neutrino, $\

Huo, W J; Huo, Wu-Jun; Feng, Tai-Fu

2002-01-01T23:59:59.000Z

10

Neutrino masses and heavy triplet leptons at the LHC: Testability of the type III seesaw mechanism  

Science Conference Proceedings (OSTI)

We study LHC signatures of the type III seesaw mechanism in which SU(2){sub L} triplet leptons are introduced to supply the heavy seesaw masses. To detect the signals of these heavy triplet leptons, one needs to understand their decays to standard model particles which depend on how light and heavy leptons mix with each other. We concentrate on the usual solutions with small light and heavy lepton mixing of the order of the square root of the ratio of light and heavy masses, (m{sub {nu}}/M{sub {nu}}{sub {sub R}}){sup 1/2}. This class of solutions can lead to a visible displaced vertex detectable at the LHC which can be used to distinguish small mixing and large mixing between light and heavy leptons. We show that, in this case, the couplings of light and heavy triplet leptons to gauge and Higgs bosons, which determine the decay widths and branching ratios, can be expressed in terms of light neutrino masses and their mixing. Using these relations, we study heavy triplet lepton decay patterns and production cross section at the LHC. If these heavy triplet leptons are below a TeV or so, they can be easily produced at the LHC due to their gauge interactions from being nontrivial representations of SU(2){sub L}. We consider two ideal production channels, (1) E{sup +}E{sup -}{yields}l{sup +}l{sup +}l{sup -}l{sup -}jj (l=e, {mu}, {tau}) and (2) E{sup {+-}}N{yields}l{sup {+-}}l{sup {+-}}jjjj in detail. For case 1, we find that with one or two of the light leptons being {tau} it can also be effectively studied. With judicious cuts at the LHC, the discovery of the heavy triplet leptons as high as a TeV can be achieved with 100 fb{sup -1} integrated luminosity.

Li Tong [Center for High Energy Physics, Peking University, Beijing, 100871 (China); He Xiaogang [Center for High Energy Physics, Peking University, Beijing, 100871 (China); Department of Physics and Center for Theoretical Sciences, National Taiwan University, Taipei, Taiwan (China)

2009-11-01T23:59:59.000Z

11

Glossary Item - Neutrino  

NLE Websites -- All DOE Office Websites (Extended Search)

that rarely interact with matter. Scientists know of three types of neutrinos: electron-neutrinos, muon-neutrinos and tau-neutrinos. Wolfgang Pauli first proposed the...

12

Probing Heavy-Light Neutrino Mixing in Left-Right Seesaw Models at the LHC  

E-Print Network (OSTI)

We show that in TeV-scale left-right (L-R) symmetric seesaw models, there are new dominant contributions to the collider signals of heavy Majorana neutrinos arising from the heavy-light neutrino mixing, which directly probe the seesaw matrix in a certain class of models. We propose a way to distinguish this contribution from the widely discussed one that only probes the Majorana nature of the heavy right-handed neutrinos, by analyzing some simple kinematical variables. We find that in this class of L-R seesaw models the existing LHC data already yield slightly stronger constraints on the heavy-light neutrino mixing than those derived for standard seesaw models, and the improvement will be significant as more data are collected.

Chien-Yi Chen; P. S. Bhupal Dev; R. N. Mohapatra

2013-06-10T23:59:59.000Z

13

Determining the heavy seesaw neutrino mass matrix from low-energy parameters  

E-Print Network (OSTI)

We explore how the seesaw sector in neutrino mass models may be constrained through symmetries to be completely determined in terms of low-energy mass, mixing angle and CP-violating phase observables. The key ingredients are intra-family symmetries to determine the neutrino Dirac mass matrix in terms of the charged-lepton or quark mass matrices, together with inter-family or flavor symmetries to determine diagonalization matrices. Implications for leptogenesis and collider detection of heavy neutral leptons are discussed. We show that leptogenesis can succeed in small regions of parameter space for the case where the neutrino Dirac mass matrix equals the up-quark mass matrix. The model where the neutrino Dirac mass matrix equals the charged-lepton mass matrix can yield a heavy neutral lepton as light as about 1 TeV, but detecting such a particle will be difficult.

He, Xiao-Gang; Volkas, Raymond R

2008-01-01T23:59:59.000Z

14

Determining the heavy seesaw neutrino mass matrix from low-energy parameters  

E-Print Network (OSTI)

We explore how the seesaw sector in neutrino mass models may be constrained through symmetries to be completely determined in terms of low-energy mass, mixing angle and CP-violating phase observables. The key ingredients are intra-family symmetries to determine the neutrino Dirac mass matrix in terms of the charged-lepton or quark mass matrices, together with inter-family or flavor symmetries to determine diagonalization matrices. Implications for leptogenesis and collider detection of heavy neutral leptons are discussed. We show that leptogenesis can succeed in small regions of parameter space for the case where the neutrino Dirac mass matrix equals the up-quark mass matrix. The model where the neutrino Dirac mass matrix equals the charged-lepton mass matrix can yield a heavy neutral lepton as light as about 1 TeV, but detecting such a particle will be difficult.

Xiao-Gang He; Sandy S. C. Law; Raymond R. Volkas

2008-10-07T23:59:59.000Z

15

Determining the heavy seesaw neutrino mass matrix from low-energy parameters  

Science Conference Proceedings (OSTI)

We explore how the seesaw sector in neutrino mass models may be constrained through symmetries to be completely determined in terms of low-energy mass, mixing angle and CP-violating phase observables. The key ingredients are intrafamily symmetries to determine the neutrino Dirac mass matrix in terms of the charged-lepton or quark mass matrices, together with interfamily or flavor symmetries to determine diagonalization matrices. Implications for leptogenesis and collider detection of heavy neutral leptons are discussed. We show that leptogenesis can succeed in small regions of parameter space for the case where the neutrino Dirac mass matrix equals the up-quark mass matrix. The model where the neutrino Dirac mass matrix equals the charged-lepton mass matrix can yield a heavy neutral lepton as light as about 1 TeV, but detecting such a particle will be difficult.

He Xiaogang [Department of Physics, Center for Theoretical Sciences and LeCosPA Center, National Taiwan University, Taipei 10617, Taiwan (China); Law, Sandy S. C.; Volkas, Raymond R. [School of Physics, University of Melbourne, Victoria 3010 (Australia)

2008-12-01T23:59:59.000Z

16

The role of the Higgs meson in the cosmological constraint on the mass of very heavy neutrinos  

Science Conference Proceedings (OSTI)

According to LEP experiments of the measurement of the width and height of a Z-boson peak, there are three neutrino species. However, this constraint applies only to light neutrinos with mass m 44 GeV. Because the experimental search for neutrinos on accelerators at very high energies ({ge}M{sub Z}) is a difficult problem, the investigation of indirect astrophysical effects becomes an important source of information on the properties of new particles. According to the Big Bang theory, the background of relic neutrinos also containing new species of very heavy neutrinos (if they exist) should exist in the Universe, and their annihilation in the halo of the Galaxy could lead to peculiarities in the spectrum of cosmic rays. The astrophysical constraints on the mass of heavy neutrinos were obtained by analyzing the spectra of cosmic electrons and photons and by using the idea about neutrino condensation in the time-dependent gravitational field of collapsing matter. In this paper, the authors take into account a finite mass of a Higgs meson and show how neutrino annihilation into a Higgs meson, which decays to a W pair modifies the restriction on heavy neutrino mass.

Konoplich, R.V.; Sorokina, E.V.; Khlopov, M.Yu. [Moscow Institute of Engineering Physics (Russian Federation)

1994-07-01T23:59:59.000Z

17

Tau Physics 2006: Summary & Outlook  

E-Print Network (OSTI)

A large amount of new results have been presented at TAU2006. The highlights of the workshop, the present status of a few selected topics on lepton physics (universality, QCD tests, V_{us} determination from tau decay, g-2, neutrino oscillations, lepton-flavour violation) and the prospects for future improvements are briefly summarized.

Antonio Pich

2007-02-07T23:59:59.000Z

18

Neutrino Factories  

SciTech Connect

Over the last decade there has been significant progress in developing the concepts and technologies needed to produce, capture and accelerate O(10{sup 21}) muons/year. This prepares the way for a Neutrino Factory (NF) in which high energy muons decay within the straight sections of a storage ring to produce a beam of neutrinos and anti-neutrinos. The NF concept was proposed in 1997 at a time when the discovery that the three known types of neutrino ({nu}{sub e}, {nu}{sub {mu}}, {nu}{sub {tau}}) can change their flavor as they propagate through space (neutrino oscillations) was providing a first glimpse of physics beyond the Standard Model. This development prepares the way for a new type of neutrino source: a Neutrino Factory. This article reviews the motivation, design and R&D for a Neutrino Factory.

Geer, Steve; /Fermilab

2010-01-01T23:59:59.000Z

19

neutrino.html  

NLE Websites -- All DOE Office Websites (Extended Search)

Fall 2000 Fall 2000 Tau Neutrino Evidence Announced at Fermilab This summer scientists at Fermi National Accelerator Laboratory announced the first direct evidence for the subatomic particle, the tau neutrino. The tau is an almost massless particle that carries no electric charge and barely interacts with surrounding matter. Previous experiments showed indirect evidence for its existence, but it had not been observed directly as yet. The tau is the third neutrino of the Standard Model of elementary particles, a theoretical description that groups all particles into three generations. The first electron neutrino was discovered in 1956, the muon in 1962. The Fermilab experiment responsible for the announcement is the Direct Observation of the Nu Tau (DONUT) experiment. DONUT is a collaboration of

20

Is Dark Matter Heavy Because of Electroweak Symmetry Breaking? Revisiting Heavy Neutrinos  

E-Print Network (OSTI)

A simple and well-motivated explanation for the origin of dark matter is that it consists of thermal relic particles that get their mass entirely through electroweak symmetry breaking. The simplest models implementing this possibility predict a dark matter candidate that consists of a mixture of two Dirac neutrinos with opposite isospin, and so has suppressed coupling to the Z. These models predict dark matter masses of m_{DM}~45 GeV or m_{DM}~90-95 GeV and WIMP-neutron spin-independent cross sections \\sigma_{WIMP-n}~10^{-6}-10^{-8} pb. Current direct dark matter searches are probing a portion of the parameter space of these models while future experiments sensitive to \\sigma_{WIMP-n}~10^{-8} pb will probe the remainder. An enhancement of the galactic halo gamma ray and positron flux coming from annihilations of these particles is also expected across the ~1-100 GeV range. The framework further suggests an environmental explanation of the hierarchy between the weak and Planck scales and of the small value of the cosmological constant relative to the weak scale.

Philip C. Schuster; Natalia Toro

2005-06-08T23:59:59.000Z

Note: This page contains sample records for the topic "tau neutrinos heavy" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Neutrino telescopes as a probe of active and sterile neutrino mixings  

E-Print Network (OSTI)

If the ultrahigh-energy (UHE) neutrino fluxes produced from a distant astrophysical source can be measured at a km^3-size neutrino telescope, they will provide a promising way to help determine the flavor mixing pattern of three active neutrinos. Considering the conventional UHE neutrino source with the flavor ratio \\phi_e : \\phi_\\mu : \\phi_\\tau = 1 : 2 : 0, I show that \\phi^D_e : \\phi^D_\\mu : \\phi^D_\\tau = (1 -2 \\Delta) : (1 +\\Delta) : (1 +\\Delta) holds at the detector of a neutrino telescope, where \\Delta characterizes the effect of \\mu-\\tau symmetry breaking (i.e., \\theta_13 \

Xing, Zhi-zhong

2007-01-01T23:59:59.000Z

22

Neutrino telescopes as a probe of active and sterile neutrino mixings  

E-Print Network (OSTI)

If the ultrahigh-energy (UHE) neutrino fluxes produced from a distant astrophysical source can be measured at a km^3-size neutrino telescope, they will provide a promising way to help determine the flavor mixing pattern of three active neutrinos. Considering the conventional UHE neutrino source with the flavor ratio \\phi_e : \\phi_\\mu : \\phi_\\tau = 1 : 2 : 0, I show that \\phi^D_e : \\phi^D_\\mu : \\phi^D_\\tau = (1 -2 \\Delta) : (1 +\\Delta) : (1 +\\Delta) holds at the detector of a neutrino telescope, where \\Delta characterizes the effect of \\mu-\\tau symmetry breaking (i.e., \\theta_13 \

Zhi-zhong Xing

2007-11-27T23:59:59.000Z

23

Isospin-Violating Dark Matter and Neutrinos From the Sun  

E-Print Network (OSTI)

We study the indirect detection of dark matter through neutrino flux from their annihilation in the center of the Sun, in a class of theories where the dark matter-nucleon spin-independent interactions break the isospin symmetry. We point out that, while the direct detection bounds with heavy targets like Xenon are weakened and reconciled with the positive signals in DAMA and CoGeNT experiments, the indirect detection using neutrino telescopes can impose a relatively stronger constraint and brings tension to such explanation, if the annihilation is dominated by heavy quark or $\\tau$-lepton final states. As a consequence, the qualified isospin violating dark matter candidate has to preferably annihilate into light flavors.

Shao-Long Chen; Yue Zhang

2011-06-20T23:59:59.000Z

24

MINOS Sterile Neutrino Search  

SciTech Connect

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 {nu}{sub {mu}} {yields} V{sub {tau}} 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 {approx}2.5 x 10{sup 20} 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.

Koskinen, David Jason; /University Coll. London

2009-09-01T23:59:59.000Z

25

Nucleosynthesis and Neutrinos  

SciTech Connect

Neutrinos play the critical roles in nucleosynthesis of light-to-heavy mass nuclei in core-collapse supernovae. We study the nucleosynthesis induced by neutrino interactions and find suitable average neutrino temperatures in order to explain the observed solar system abundances of several isotopes {sup 7}Li, {sup 11}B, {sup 138}La and {sup 180}Ta. These isotopes are predominantly synthesized by the supernova {nu}-process. We also study the neutrino oscillation effects on their abundances and propose a method to determine the unknown neutrino oscillation parameters, i.e. {theta}{sub 13} and mass hierarchy.

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

2011-05-06T23:59:59.000Z

26

Neutrino observations from the Sudbury Neutrino Observatory  

SciTech Connect

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.

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.

2001-09-24T23:59:59.000Z

27

Solar Neutrino Observations at the Sudbury Neutrino Observatory  

E-Print Network (OSTI)

The Sudbury Neutrino Observatory (SNO) is a 1000-tonne heavy water Cherenkov detector. Its usage of \\dto as target allows the simultaneous measurements of the $\

Poon, A W P

2002-01-01T23:59:59.000Z

28

Solar Neutrino Observations at the Sudbury Neutrino Observatory  

E-Print Network (OSTI)

The Sudbury Neutrino Observatory (SNO) is a 1000-tonne heavy water Cherenkov detector. Its usage of \\dto as target allows the simultaneous measurements of the $\

A. W. P. Poon

2002-11-06T23:59:59.000Z

29

Determining the Flavour Content of the Low-Energy Solar Neutrino Flux  

E-Print Network (OSTI)

We study the sensitivity of the HELLAZ and Borexino solar neutrino experiments on discriminating the neutrino species nu_e, anti-nu_e, nu_{mu,tau}, anti-nu_{mu,tau}, and nu_{sterile} using the difference in the recoil electron kinetic energy spectra in elastic neutrino-electron scattering. We find that one can observe a non-vanishing nu_{mu,tau} component in the solar neutrino flux, especially when the nu_e survival probability is low. Also, if the data turn out to be consistent with nu_e nu_{mu,tau} oscillations, an anti-nu_e component can be excluded effectively.

De Gouva, A; Gouvea, Andre de; Murayama, Hitoshi

2000-01-01T23:59:59.000Z

30

TAU Grupo | Open Energy Information  

Open Energy Info (EERE)

Grupo Jump to: navigation, search Name TAU Grupo Place Spain Sector Services Product String representation "Four services c ... e (TAU-Econat)." is too long. References TAU...

31

Tau tau Fusion to SUSY Higgs Bosons at a Photon Collider: Measuring tan(beta)  

E-Print Network (OSTI)

Tau tau fusion to light h and heavy H,A Higgs bosons is investigated in the Minimal Supersymmetric Standard Model (MSSM) at a photon collider as a promising channel for measuring large values of tan(beta). For standard design parameters of a photon collider an error close to unity, uniform for tan(beta) above 10, may be expected, improving on complementary measurements at LHC and e+e- linear colliders.

S. Y. Choi; J. Kalinowski; J. S. Lee; M. M. Muehlleitner; M. Spira; P. M. Zerwas

2004-07-05T23:59:59.000Z

32

Solar Neutrinos  

NLE Websites -- All DOE Office Websites (Extended Search)

Solar Neutrinos at the Conclusion of the Sudbury Neutrino Observatory Noah Oblath April 22, 2008 The study of solar neutrinos began with the idea that one could use the neutrinos...

33

Neutrino Oscillations and Blazars  

E-Print Network (OSTI)

Three independent predictions follow from postulating the existence of protons co-accelerated with electrons in extragalactic jets (i) multi-TeV gamma ray emission from nearby blazars, (ii) extragalactic cosmic ray protons up to 10^20 eV, and (iii) extragalactic neutrinos up to 5 10^18 eV. Recent gamma ray observations of Mrk 421 and Mrk 501 employing the air-Cerenkov technique are consistent with the predicted gamma ray spectrum, if one corrects for pair attenuation on the infrared background. Prediction (ii) is consistent with cosmic ray data, if one requires that jets are responsible for at least a sizable fraction of the extragalactic gamma ray background. With kubic kilometer neutrino telescopes, it will be possible to test (iii), although the muon event rates are rather low. Neutrino oscillations can increase the event rate by inducing tau-cascades removing the Earth shadowing effect.

Karl Mannheim

1998-12-22T23:59:59.000Z

34

Neutrino Oscillations and Blazars  

E-Print Network (OSTI)

Three independent predictions follow from postulating the existence of protons co-accelerated with electrons in extragalactic jets (i) multi-TeV gamma ray emission from nearby blazars, (ii) extragalactic cosmic ray protons up to ? 10 20 eV, and (iii) extragalactic neutrinos up to ? 5 10 18 eV. Recent gamma ray observations of Mrk 421 and Mrk 501 employing the air-Cerenkov technique are consistent with the predicted gamma ray spectrum, if one corrects for pair attenuation on the infrared background. Prediction (ii) is consistent with cosmic ray data, if one requires that jets are responsible for a at least a sizable fraction of the extragalactic gamma ray background. With kubic kilometer neutrino telescopes, it will be possible to test (iii), although the muon event rates are rather low. Neutrino oscillations can increase the event rate by inducing tau-cascades removing the so-called Earth shadowing effect. 1

Karl Mannheim

1999-01-01T23:59:59.000Z

35

Aspects of Neutrino Production in Supernovae  

E-Print Network (OSTI)

I discuss neutrino production in supernovae (SNe) and the detection of both Galactic core collapse events and the diffuse extra-galactic MeV neutrino background expected from the integrated history of star formation. In particular, I consider what processes might affect our expectations for both. I focus on ``rapid'' rotation, defined as leading to millisecond initial neutron star spin periods. Rotation affects the neutrino luminosity, the average neutrino energy, the duration of the Kelvin-Helmholtz cooling epoch, and the ratios of luminosities and average energies between neutrino species; it can strongly suppresses the anti-electron as well as mu, anti-mu, tau, and anti-tau neutrino fluxes relative to those for the electron neutrinos. As a result, depending on the prevalence of rapid rotation in SN progenitors through cosmic time, this may affect predictions for the MeV neutrino background and the history of nucleosynthetic enrichment. I emphasize connections between the MeV neutrino background and tracers of the star formation rate density at high redshift in other neutrino and photon wavebands.

Todd A. Thompson

2006-08-10T23:59:59.000Z

36

Theta-13 as a Probe of Mu-Tau symmetry for Leptons  

E-Print Network (OSTI)

Many experiments are being planned to measure the neutrino mixing parameter $\\theta_{13}$ using reactor as well as accelerator neutrino beams. In this note, the theoretical significance of a high precision measurement of this parameter is discussed. It is emphasized that it will provide crucial information about different ways to understand the origin of large atmospheric neutrino mixing and move us closer towards determining the neutrino mass matrix. For instance if exact $\\mu\\leftrightarrow \\tau$ symmetry in the neutrino mass matrix is assumed to be the reason for maximal $\

R. N. Mohapatra

2004-08-17T23:59:59.000Z

37

Solar Neutrino Physics  

SciTech Connect

With its heavy water target, the Sudbury Neutrino Observatory (SNO) offers the unique opportunity to measure both the 8B flux of electron neutrinos from the Sun and, independently, the flux of all active neutrino species reaching the Earth. A model-independent test of the hypothesis that neutrino oscillations are responsible for the observed solar neutrino deficit can be made by comparing the charged-current (CC) and neutral-current (NC) rates. This LDRD proposal supported the research and development necessary for an assessment of backgrounds and performance of the SNO detector and the ability to extract the NC/CC-Ratio. Particular emphasis is put upon the criteria for deployment and signal extraction from a discrete NC detector array based upon ultra-low background 3He proportional counters.

Bowles, T.J.; Brice, S.J.; Esch, E.-I.; Fowler, M.M.; Goldschmidt, A.; Hime, A.; McGirt, F.; Miller, G.G.; Thornewell, P.M.; Wilhelmy, J.B.; Wouters, J.M.

1999-07-15T23:59:59.000Z

38

Search for a new charged heavy vector boson decaying to an electron-neutrino pair in p anti-p collisions at s**(1/2) = 1.96 TeV  

SciTech Connect

We present results on a search for a heavy charged vector boson, W', decaying to an electron-neutrino pair in p{bar p} collisions at {radical}s = 1.96 TeV using a data sample corresponding to an integrated luminosity of 205 pb{sup -1}. We found no evidence of this decay channel, and set 95% confidence level limits on the production cross section times branching fraction assuming the light neutrino. We also set the limit on the W' boson mass at M{sub W'} > 788 GeV/c{sup 2}, assuming the standard model strength couplings.

Kim, Jieun; /Kyungpook Natl. U.

2005-06-01T23:59:59.000Z

39

Neutrino Oscillations with Reactor Neutrinos  

E-Print Network (OSTI)

Prospect measurements of neutrino oscillations with reactor neutrinos are reviewed in this document. The following items are described: neutrinos oscillations status, reactor neutrino experimental strategy, impact of uncertainties on the neutrino oscillation sensitivity and, finally, the experiments in the field. This is the synthesis of the talk delivered during the NOW2006 conference at Otranto (Italy) during September 2006.

Anatael Cabrera

2007-01-11T23:59:59.000Z

40

Neutrino Phenomenology  

E-Print Network (OSTI)

A general overview of neutrino physics is given, starting with a historical account of the development of our understanding of neutrinos and how they helped to unravel the structure of the Standard Model. We discuss why it is so important to establish if neutrinos are massive and the indications in favor of non-zero neutrino masses are discussed, including the recent results on atmospheric and solar neutrinos and their confirmation with artificial neutrino sources.

Esteban Roulet

2004-12-27T23:59:59.000Z

Note: This page contains sample records for the topic "tau neutrinos heavy" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Measurement of sigma(ppbar->Z) Br(Z->tau+tau-) and search for Higgs bosons decaying to tau+tau- at s**(1/2) = 1.96 TeV  

SciTech Connect

The resonant production of tau-lepton pairs is as interesting for the study of Standard Model (SM) physics as the production of lighter leptons pairs. For new phenomena, such as Higgs boson production or in case new particles beyond the SM would arise, the detection of (resonant) pairs of tau leptons becomes much more interesting. This is due to the fact that tau leptons are much heavier than the other leptons, which increases the chance that these new phenomena would be observed first in this channel. Unfortunately their clean detection is far more difficult than that of muons or electrons. The cross section times branching ratio {sigma}{center_dot} Br for the process p{bar p} {yields} Z {yields} {tau}{sup +}{tau}{sup -} was measured at {radical}s = 1.96 GeV using 1.0 fb{sup -1} of data collected by the D0 experiment. This measurement was performed in the channel in which one of the tau leptons decays to a muon and neutrinos, while the other decays either hadronically or to an electron and neutrinos. A set of 1511 events, of which about 20% estimated background, passed all selection criteria. The trigger and muon reconstruction efficiencies, as well as the efficiency for track reconstruction were obtained from data using the 'tag and probe' method on Z {yields} {mu}{sup +}{mu}{sup -} events. The multijet background was estimated from the sample of events which passed all selection criteria but in which the muon and the tau candidate had the same charge. The W {yields} {mu}{nu} + jets background was modeled by Monte Carlo simulations, but normalized to data. All the other backgrounds, as well as the efficiency for Z {yields} {tau}{sup +}{tau}{sup -} events were estimated using simulated events normalized to the theoretical calculations of cross sections at next-to-leading order or next-to-next-to-leading order. The energy of the tau candidates was corrected for the estimated response of the charged pions in the calorimeter, which is of the order 50-80%. Since the charged pion response in data was not well reproduced by the default simulation of hadronic interactions (Geisha), a different simulation (gCALOR) was used to obtain an estimated charged pion response consistent with the one measured in data. This tau energy correction method makes use of the superior resolution of the track momentum measurement compared to the resolution of the tau candidate energy as measured by the calorimeter, which leads to a better data--simulation agreement and a decrease of 10% in the resolution of the visible mass peak. The result of this measurement is {sigma}(p{bar p} {yields} Z) {center_dot} Br(Z {yields} {tau}{sup +}{tau}{sup -}) = 240 {+-} 8(stat) {+-} 12(syst) {+-} 15(lumi) pb, in good agreement with the theoretical predictions of 241.6{sub -3.2}{sup +3.6} pb [79] or 251.9{sub -12}{sup +5.1} pb [93-95], as well as with other measurements performed by the D0 and CDF experiments in all channels in which the Z boson decays leptonically [96-100]. This is the most precise Z boson cross section measurement to date performed in the tau lepton channel at hadron colliders. The analysis demonstrates the ability of the D0 experiment to identify tau leptons decaying hadronically with good efficiency and high purity, a challenging task in p{bar p} collisions where the number of jets resembling tau leptons is very high. This achievement forms a solid basis for other analyses using hadronic tau lepton decays, such as the search for the Higgs boson decaying into tau-lepton pairs, which was performed for the last part of this thesis.

Galea, Cristina Florina; /Nijmegen U.

2008-01-01T23:59:59.000Z

42

Neutrino Physics  

DOE R&D Accomplishments (OSTI)

The prediction and verification of the neutrino are reviewed, together with the V A theory for its interactions (particularly the difficulties with the apparent existence of two neutrinos and the high energy cross section). The Brookhaven experiment confirming the existence of two neutrinos and the cross section increase with momentum is then described, and future neutrino experiments are considered. (D.C.W.)

Lederman, L. M.

1963-01-09T23:59:59.000Z

43

Neutrino Oscillations and Blazars  

E-Print Network (OSTI)

Three independent predictions follow from postulating the existence of protons co-accelerated with electrons in extragalactic jets (i) multi-TeV gamma ray emission from nearby blazars, (ii) extragalactic cosmic ray protons up to ray observations of Mrk 421 and Mrk 501 employing the air-Cerenkov technique are consistent with the predicted gamma ray spectrum, if one corrects for pair attenuation on the infrared background. Prediction (ii) is consistent with cosmic ray data, if one requires that jets are responsible for the extragalactic gamma ray background above 100 MeV. With kubic kilometer neutrino telescopes, it will be possible to test (iii), although the muon event rates are rather low. Neutrino oscillations can increase the event rate by inducing tau-cascades removing the Earth shadowing effect.

Mannheim, K

1999-01-01T23:59:59.000Z

44

Measurements of the tau Mass and Mass Difference of the tau^+ and tau^- at BABAR  

SciTech Connect

The authors present the result of a precision measurement of the mass of the {tau} lepton, M{sub {tau}}, based on 423 fb{sup -1} of data recorded at the {Upsilon}(4S) resonance with the BABAR detector. Using a pseudomass endpoint method, they determine the mass to be 1776.68 {+-} 0.12(stat) {+-} 0.41(syst) MeV. They also measure the mass difference between the {tau}{sup +} and {tau}{sup -}, and obtain (M{sub {tau}{sup +}} - M{sub {tau}{sup -}})/M{sub AVG}{sup {tau}} = (-3.4 {+-} 1.3(stat) {+-} 0.3(syst)) x 10{sup -4}, where M{sub AVG}{sup {tau}} is the average value of M{sub {tau}{sup +}} and M{sub {tau}{sup -}}.

Aubert, B.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Battaglia, M.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /INFN, Naples /Naples U. /INFN, Naples /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /Pennsylvania U. /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

2009-10-30T23:59:59.000Z

45

Neutrino Oscillations  

E-Print Network (OSTI)

This review summarizes recent experimental and theoretical progress in determining neutrino mixing angles and masses through neutrino oscillations. We describe the basic physics of oscillation phenomena in vacuum and matter, as well as the status of solar, reactor, atmospheric, and accelerator neutrino experiments that probe these phenomena. The results from current global analyses of neutrino parameters are given. Future efforts that may improve the precision with which these parameters are known or probe new aspects of the neutrino mixing matrix are described.

A. B. Balantekin; W. C. Haxton

2013-03-09T23:59:59.000Z

46

Neutrino Unification  

E-Print Network (OSTI)

Present neutrino data are consistent with neutrino masses arising from a common seed at some ``neutrino unification'' scale $M_X$. Such a simple theoretical ansatz naturally leads to quasi-degenerate neutrinos that could lie in the electron-volt range with neutrino mass splittings induced by renormalization effects associated with supersymmetric thresholds. In such a scheme the leptonic analogue of the Cabibbo angle $\\theta_{\\odot}$ describing solar neutrino oscillations is nearly maximal. Its exact value is correlated with the smallness of $\\theta_{reactor}$. These features agree both with latest data on the solar neutrino spectra and with the reactor neutrino data. The two leading mass-eigenstate neutrinos present in \

P. H. Chankowski; A. Ioannisian; S. Pokorski; J. W. F Valle

2000-11-10T23:59:59.000Z

47

Particle Data Group - 2009 Particle Listings  

NLE Websites -- All DOE Office Websites (Extended Search)

for Axions (A0) and Other Very Light Bosons, Searches for Collapse Gauge and Higgs Boson table LEPTONS (e, mu, tau, neutrinos, heavy leptons ...) electron muon tau Heavy...

48

Particle Data Group - Particle Listings - 2007 update  

NLE Websites -- All DOE Office Websites (Extended Search)

for Axions (A0) and Other Very Light Bosons, Searches for Collapse Gauge and Higgs Boson table LEPTONS (e, mu, tau, neutrinos, heavy leptons ...) electron muon tau Heavy...

49

Particle Data Group - 2011 Particle Listings  

NLE Websites -- All DOE Office Websites (Extended Search)

for Axions (A0) and Other Very Light Bosons, Searches for Collapse Gauge and Higgs Boson table LEPTONS (e, mu, tau, neutrinos, heavy leptons ...) electron muon tau Heavy...

50

Evidence for Neutrino Oscillations I: Solar and Reactor Neutrinos  

E-Print Network (OSTI)

This paper discusses evidence for neutrino oscillations obtained from measurements with solar neutrinos and reactor neutrinos.

A. B. McDonald

2004-12-06T23:59:59.000Z

51

Neutrino Superbeams  

NLE Websites -- All DOE Office Websites (Extended Search)

Upgraded conventional neutrino beams: Neutrino superbeams Upgraded conventional neutrino beams: Neutrino superbeams The capabilities of greatly upgraded conventional neutrino beams and the comparison with neutrino factories is under study. This page collects together some useful working information-- and at the bottom you can find links to studies that have already been done! GROUP REPORT: Oscillation Measurements with Upgraded Conventional Neutrino Beams V. Barger et al., hep-ex/0103052 (FERMILAB-FN-703), Addendum to Report FN-692 to the Fermilab Directorate, March 5, 2001. MI upgrade limitations Conf-97-199, W. Chou NUMI low energy beam with L = 732 km uoscillation signals for point IA1 (LMA scenario) but with sin**2 2theta(13) = 0.01, from Steve Geer. NUMI medium energy beam with L = 2800 km oscillation signals for

52

Measurement of the ?[subscript e] and total [superscript 8]B solar neutrino fluxes with the Sudbury Neutrino Observatory phase-III data set  

E-Print Network (OSTI)

This paper details the solar neutrino analysis of the 385.17-day phase-III data set acquired by the Sudbury Neutrino Observatory (SNO). An array of [superscript 3]He proportional counters was installed in the heavy-water ...

Formaggio, Joseph A.

53

Sensitivity of the IceCube neutrino detector to dark matter annihilating in dwarf galaxies  

SciTech Connect

In this paper, we compare the relative sensitivities of gamma-ray and neutrino observations to the dark matter annihilation cross section in leptophilic models such as have been designed to explain PAMELA data. We investigate whether the high energy neutrino telescope IceCube will be competitive with current and upcoming searches by gamma-ray telescopes, such as the Atmospheric Cerenkov Telescopes (H.E.S.S., VERITAS, and MAGIC), or the Fermi Gamma-Ray Space Telescope, in detecting or constraining dark matter particles annihilating in dwarf spheroidal galaxies. We find that after 10 years of observation of the most promising nearby dwarfs, IceCube will have sensitivity comparable to the current sensitivity of gamma-ray telescopes only for very heavy (m{sub X} > or approx. 7 TeV) or relatively light (m{sub X} < or approx. 200 GeV) dark matter particles which annihilate primarily to {mu}{sup +{mu}-}. If dark matter particles annihilate primarily to {tau}{sup +{tau}-}, IceCube will have superior sensitivity only for dark matter particle masses below the 200 GeV threshold of current Atmospheric Cerenkov Telescopes. If dark matter annihilations proceed directly to neutrino-antineutrino pairs a substantial fraction of the time, IceCube will be competitive with gamma-ray telescopes for a much wider range of dark matter masses. K. F. would like to thank the Aspen Center for Physics and the Texas Cosmology Center, and P. S. would like to thank MCTP.

Sandick, Pearl [Theory Group and Texas Cosmology Center, University of Texas at Austin, Texas 78712 (United States); Spolyar, Douglas [Center for Particle Astrophysics, Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States); Department of Physics, University of California, Santa Cruz, California 95064 (United States); Buckley, Matthew [Department of Physics, California Institute of Technology, Pasadena, California 91125 (United States); Freese, Katherine [Michigan Center for Theoretical Physics, University of Michigan, Ann Arbor, Michigan 48109 (United States); Hooper, Dan [Center for Particle Astrophysics, Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States); Department of Astronomy and Astrophysics, University of Chicago, Chicago, Illinois 60638 (United States)

2010-04-15T23:59:59.000Z

54

The physics of heavy flavors  

SciTech Connect

We review the physics of heavy quark flavors, including weak decays, onium, tau leptons, mixing, the Kobayashi-Maskawa matrix, and CP violation in B decay. 36 refs., 12 figs.

Gilman, F.J.

1987-12-01T23:59:59.000Z

55

Neutrino Oscillometry  

E-Print Network (OSTI)

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

Vergados, J D; Novikov, Yu N

2010-01-01T23:59:59.000Z

56

Neutrino Oscillometry  

E-Print Network (OSTI)

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

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

2010-10-21T23:59:59.000Z

57

Solar Neutrinos  

DOE R&D Accomplishments (OSTI)

The prospect of studying the solar energy generation process directly by observing the solar neutrino radiation has been discussed for many years. The main difficulty with this approach is that the sun emits predominantly low energy neutrinos, and detectors for observing low fluxes of low energy neutrinos have not been developed. However, experimental techniques have been developed for observing neutrinos, and one can foresee that in the near future these techniques will be improved sufficiently in sensitivity to observe solar neutrinos. At the present several experiments are being designed and hopefully will be operating in the next year or so. We will discuss an experiment based upon a neutrino capture reaction that is the inverse of the electron-capture radioactive decay of argon-37. The method depends upon exposing a large volume of a chlorine compound, removing the radioactive argon-37 and observing the characteristic decay in a small low-level counter.

Davis, R. Jr.; Harmer, D. S.

1964-12-00T23:59:59.000Z

58

Light Sterile Neutrinos and Short Baseline Neutrino Oscillation Anomalies  

E-Print Network (OSTI)

We study two possible explanations for short baseline neutrino oscillation anomalies, such as the LSND and MiniBooNE anti-neutrino data, and for the reactor anomaly. The first scenario is the mini-seesaw mechanism with two eV-scale sterile neutrinos. We present both analytic formulas and numerical results showing that this scenario could account for the short baseline and reactor anomalies and is consistent with the observed masses and mixings of the three active neutrinos. We also show that this scenario could arise naturally from an effective theory containing a TeV-scale VEV, which could be related to other TeV-scale physics. The minimal version of the mini-seesaw relates the active-sterile mixings to five real parameters and favors an inverted hierarchy. It has the interesting property that the effective Majorana mass for neutrinoless double beta decay vanishes, while the effective masses relevant to tritium beta decay and to cosmology are respectively around 0.2 and 2.4 eV. The second scenario contains only one eV-scale sterile neutrino but with an effective non-unitary mixing matrix between the light sterile and active neutrinos. We find that though this may explain the anomalies, if the non-unitarity originates from a heavy sterile neutrino with a large (fine-tuned) mixing angle, this scenario is highly constrained by cosmological and laboratory observations.

JiJi Fan; Paul Langacker

2012-01-31T23:59:59.000Z

59

Neutrino Mass and Grand Unification  

E-Print Network (OSTI)

Seesaw mechanism appears to be the simplest and most appealing way to understand small neutrino masses observed in recent experiments. It introduces three right handed neutrinos with heavy masses to the standard model, with at least one mass required by data to be close to the scale of conventional grand unified theories. This may be a hint that the new physics scale implied by neutrino masses and grand unification of forces are one and the same. Taking this point of view seriously, I explore different ways to resolve the puzzle of large neutrino mixings in grand unified theories such as SO(10) and models based on its subgroup $SU(2)_L\\times SU(2)_R\\times SU(4)_c$.

R. N. Mohapatra

2004-12-03T23:59:59.000Z

60

Constraining nonstandard neutrino-quark interactions with solar, reactor, and accelerator data  

Science Conference Proceedings (OSTI)

We present a reanalysis of nonstandard neutrino-down-quark interactions of electron and tau neutrinos using solar, reactor, and accelerator data. In addition updating the analysis by including new solar data from SNO phase III and Borexino, as well as new KamLAND data and solar fluxes, a key role is played in our analysis by the combination of these results with the CHARM data. The latter allows us to better constrain the axial and axial-vector electron and tau-neutrino nonstandard interaction parameters characterizing the deviations from the standard model predictions.

Escrihuela, F. J.; Valle, J. W. F. [Instituto de Fisica Corpuscular-C.S.I.C./Universitat de Valencia, Campus de Paterna, Apt 22085, E-46071 Valencia (Spain); Miranda, O. G. [Departamento de Fisica, Centro de Investigacion y de Estudios Avanzados del IPN, Apartado Postal 14-740, 07000 Mexico, DF (Mexico); Tortola, M. A. [II. Institut fuer Theoretische Physik, Universitaet Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany)

2009-11-15T23:59:59.000Z

Note: This page contains sample records for the topic "tau neutrinos heavy" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Tau identification at the Tevatron  

SciTech Connect

Methods for reconstructing and identifying the hadronic decays of tau leptons with the CDF and D0 detectors at the Fermilab Tevatron collider in Run II are described. Precision electroweak measurements of W and Z gauge boson cross sections are presented as well as results of searches for physics beyond the Standard Model with hadronically decaying tau leptons in the final state.

Levy, Stephen; /Chicago U., EFI

2005-07-01T23:59:59.000Z

62

Propagation of Neutrinos through Magnetized Gamma-Ray Burst Fireball  

E-Print Network (OSTI)

The neutrino self-energy is calculated in a weakly magnetized plasma consists of electrons, protons, neutrons and their anti-particles and using this we have calculated the neutrino effective potential up to order $M^{-4}_W$. In the absence of magnetic field it reduces to the known result. We have also calculated explicitly the effective potentials for different backgrounds which may be helpful in different environments. By considering the mixing of three active neutrinos in the medium with the magnetic field we have derived the survival and conversion probabilities of neutrinos from one flavor to another and also the resonance condition is derived. As an application of the above, we considered the dense and relativistic plasma of the Gamma-Ray Bursts fireball through which neutrinos of 5-30 MeV can propagate and depending on the fireball parameters they may oscillate resonantly or non-resonantly from one flavor to another. These MeV neutrinos are produced due to stellar collapse or merger events which trigger the Gamma-Ray Burst. The fireball itself also produces MeV neutrinos due to electron positron annihilation, inverse beta decay and nucleonic bremsstrahlung. Using the three neutrino mixing and considering the best fit values of the neutrino parameters, we found that electron neutrinos are hard to oscillate to another flavors. On the other hand, the muon neutrinos and the tau neutrinos oscillate with equal probability to one another, which depends on the neutrino energy, temperature and size of the fireball. Comparison of oscillation probabilities with and without magnetic field shows that, they depend on the neutrino energy and also on the size of the fireball. By using the resonance condition, we have also estimated the resonance length of the propagating neutrinos as well as the baryon content of the fireball.

Sarira Sahu; Nissim Fraija; Yong-Yeon Keum

2009-09-16T23:59:59.000Z

63

High Energy Neutrinos from Cosmological Gamma-Ray Burst Fireballs  

E-Print Network (OSTI)

Observations suggest that $\\gamma$-ray bursts (GRBs) are produced by the dissipation of the kinetic energy of a relativistic fireball. We show that a large fraction, $\\ge 10%$, of the fireball energy is expected to be converted by photo-meson production to a burst of $\\sim10^{14} eV$ neutrinos. A km^2 neutrino detector would observe at least several tens of events per year correlated with GRBs, and test for neutrino properties (e.g. flavor oscillations, for which upward moving $\\tau$'s would be a unique signature, and coupling to gravity) with an accuracy many orders of magnitude better than is currently possible.

Eli Waxman; John Bahcall

1997-01-30T23:59:59.000Z

64

Effect of Collective Neutrino Oscillations on the Neutrino Mechanism of Core-Collapse Supernovae  

E-Print Network (OSTI)

In the seconds after collapse of a massive star, the newborn proto-neutron star (PNS) radiates neutrinos of all flavors. The absorption of electron-type neutrinos below the radius of the stalled shockwave may drive explosions (the "neutrino mechanism"). Because the heating rate is proportional to the square of neutrino energy, flavor conversion of mu and tau neutrinos to electron-type neutrinos via collective neutrino oscillations (CnuO) may in principle increase the heating rate and drive explosions. In order to assess the potential importance of CnuO for the shock revival, we solve the steady-state boundary value problem of spherically-symmetric accretion between the PNS surface (r_nu) and the shock (r_S), including a scheme for flavor conversion via CnuO. For a given r_nu, PNS mass (M), accretion rate (Mdot), and assumed values of the neutrino energies from the PNS, we calculate the critical neutrino luminosity above which accretion is impossible and explosion results. We show that CnuO can decrease the critical luminosity by a factor of at most ~1.5, but only if the flavor conversion is fully completed inside r_S and if there is no matter suppression. The magnitude of the effect depends on the model parameters (M, Mdot, and r_nu) through the shock radius and the physical scale for flavor conversion. We quantify these dependencies and find that CnuO could lower the critical luminosity only for small M and Mdot, and large r_nu. However, for these parameter values CnuO are suppressed due to matter effects. By quantifying the importance of CnuO and matter suppression at the critical neutrino luminosity for explosion, we show in agreement with previous studies that CnuO are unlikely to affect the neutrino mechanism of core-collapse supernovae significantly.

Ondrej Pejcha; Basudeb Dasgupta; Todd A. Thompson

2011-06-28T23:59:59.000Z

65

On the 17-keV neutrino  

SciTech Connect

A brief review on the status of the 17-keV neutrino is presented. Several different experiments found spectral distortions which were consistently interpreted as evidence for a heavy neutrino admixture in [beta] decay. Recent experiments, however, rule out the existence of a 17-keV neutrino as well as escaping criticisms of earlier null results. Moreover, the majority of positive results have been reinterpreted in terms of instrumental effects, despite the need for a different explanation in each case. Anomalies persist in the low energy region of the tritium spectrum which deserve further investigation.

Hime, A.

1993-04-01T23:59:59.000Z

66

On the 17-keV neutrino  

SciTech Connect

A brief review on the status of the 17-keV neutrino is presented. Several different experiments found spectral distortions which were consistently interpreted as evidence for a heavy neutrino admixture in {beta} decay. Recent experiments, however, rule out the existence of a 17-keV neutrino as well as escaping criticisms of earlier null results. Moreover, the majority of positive results have been reinterpreted in terms of instrumental effects, despite the need for a different explanation in each case. Anomalies persist in the low energy region of the tritium spectrum which deserve further investigation.

Hime, A.

1993-04-01T23:59:59.000Z

67

Solar Neutrinos  

E-Print Network (OSTI)

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

R. G. H. Robertson

2006-02-05T23:59:59.000Z

68

Neutrino Physics: Fundamentals of Neutrino Oscillations  

E-Print Network (OSTI)

In this lecture we review some of the basic properties of neutrinos, in particular their mass and the oscillation behavior. First we discuss how to describe the neutrino mass. Then, under the assumption that neutrinos are massive and mixed, the fundamentals of the neutrino oscillations are discussed with emphasis on subtle aspects which have been overlooked in the past. We then review the terrestrial neutrino oscillation experiments in the framework of three generations of neutrinos with the standard mass hierarchy. Finally, a brief summary of the current status of the solar and atmospheric neutrino problems will be given.

C. W. Kim

1996-07-22T23:59:59.000Z

69

Search for Lepton Flavour Violating Decays Tau -> l Ks with the BABAR Detector  

SciTech Connect

We present the search for the lepton flavour violating decay {tau} {yields} lK{sup 0}{sub s} with the BaBar experiment data. This process and many other lepton flavour violating {tau} decays, like {tau} {yields} {mu}{gamma} and {tau} {yields} lll, are one of the most promising channel to search for evidence of new physics. According to the Standard Model and the neutrino mixing parameters, branching fractions are estimated well below 10{sup -14}, but many models of new physics allow for branching fractions values close to the present experimental sensitivity. This analysis is based on a data sample of 469fb{sup -1} collected by BABAR detector at the PEP-II storage ring from 1999 to 2007, equivalent to 431 millions of {tau} pairs. the BABAR experiment, initially designed for studying CP violation in B mesons, has demonstrated to be one of the most suitable environments for studying {tau} decays. The tracking system, the calorimeter and the particle identification of BABAR, together with the knowledge of the {tau} initial energy, allow an extremely powerful rejection of background events that, for this analysis, is better than 10{sup -9}. Being {tau} {yields} lK{sup 0}{sub s} a decay mode without neutrinos, the signal {tau} decay can be fully reconstructed. Kinematical constraints are used in a fit that provides a decay tree reconstruction with a high resolution. For this analysis MC simulated events play a decisive role for estimating the signal efficiency and study the residual background. High statistics MC sample are produced simulating detector conditions for different periods of data collection, in order to reduce any discrepancies with the data. When discrepancies can not be removed, we perform studies to compute a correction factor or an estimation of systematic errors that need to be included in the final measurement. A significant improvement of the current result can be reached only with a higher statistics and, therefore, with a new collider providing a luminosity from 10 to 100 times more than PEP-II. A new detector, with improved performance and able to collect data in a high background environment, is also requested to fully exploit the capability of such amount of data. In fact, only keeping the efficiency and the background as similar as possible to present ones, we will be able to scale almost linearly the estimated upper limit according to the luminosity. The strong potential of improvement for the search of lepton flavour violation {tau} decays makes the building of such a machine highly desirable.

Cenci, Riccardo; /SLAC

2009-03-20T23:59:59.000Z

70

Solar Neutrinos Before and After Neutrino 2004  

E-Print Network (OSTI)

We compare, using a three neutrino analysis, the allowed neutrino oscillation parameters and solar neutrino fluxes determined by the experimental data available Before and After Neutrino 2004. New data available after Neutrino2004 include refined KamLAND and gallium measurements. We use six different approaches to analyzing the KamLAND data. We present detailed results using all the available neutrino and anti-neutrino data for Delta m^2_{12}, tan^2 theta_{12}, sin^2 theta_{13}, and sin^2 eta (sterile fraction). Using the same complete data sets, we also present Before and After determinations of all the solar neutrino fluxes, which are treated as free parameters, an upper limit to the luminosity fraction associated with CNO neutrinos, and the predicted rate for a 7Be solar neutrino experiment. The 1 sigma (3 sigma) allowed range of Delta m^2_{21} = (8.2 +- 0.3) (^+1.0_-0.8)times 10^{-5} eV^2 is decreased by a factor of 1.7 (5), but the allowed ranges of all other neutrino oscillation parameters and neutrino fluxes are not significantly changed. Maximal mixing is disfavored at 5.8 sigma and the bound on the mixing angle theta_{13} is slightly improved to sin^2 theta_{13}reactor anti-neutrino oscillation parameters with neutrino oscillation parameters. We also show that the recent data disfavor at 91 % CL a proposed non-standard interaction description of solar neutrino oscillations.

John N. Bahcall; M. C. Gonzalez-Garcia; Carlos Pena-Garay

2004-06-28T23:59:59.000Z

71

The Neutrino Signal from Protoneutron Star Accretion and Black Hole Formation  

SciTech Connect

We discuss the formation of stellar mass black holes via protoneutron star (PNS) collapse. In the absence of an earlier explosion, the PNS collapses to a black hole due to the continued mass accretion onto the PNS. We present an analysis of the emitted neutrino spectra of all three flavors during the PNS contraction. Special attention is given to the physical conditions which depend on the input physics, e.g. the equation of state (EoS) and the progenitor model. The PNSs are modeled as the central object in core collapse simulations using general relativistic three-flavor Boltzmann neutrino transport in spherical symmetry. The simulations are launched from several massive progenitors of 40 M{omicron} and 50 M{omicron}. We analyze the electron-neutrino luminosity dependencies and construct a simple approximation for the electron-neutrino luminosity, which depends only on the physical conditions at the electron-neutrinosphere. In addition, we analyze different ({mu}, {tau})-neutrino pair-reactions separately and compare the differences during the post-bounce phases of failed core collapse supernova explosions of massive progenitors. We also investigate the connection between the increasing {mu},{tau}-neutrino luminosity and the PNS contraction during the accretion phase before black hole formation. Comparing the different post bounce phases of the progenitor models under investigation, we find large differences in the emitted neutrino spectra. These differences and the analysis of the electron-neutrino luminosity indicate a strong progenitor model dependency of the emitted neutrino signal.

Fischer, T. [University of Basel; Whitehouse, S. [University of Basel; Mezzacappa, Anthony [ORNL; Thielemann, F.-K. [University of Basel; Liebendoerfer, M. [University of Basel

2009-01-01T23:59:59.000Z

72

TAU Solar SL | Open Energy Information  

Open Energy Info (EERE)

Solar SL Jump to: navigation, search Name TAU Solar SL Place Madrid, Spain Zip 28043 Product Spanish PV project developer. References TAU Solar SL1 LinkedIn Connections...

73

Tau Trigger at the ATLAS Experiment  

Science Conference Proceedings (OSTI)

Many theoretical models, like the Standard Model or SUSY at large tan({beta}), predict Higgs bosons or new particles which decay more abundantly to final states including tau leptons than to other leptons. At the energy scale of the LHC, the identification of tau leptons, in particular in the hadronic decay mode, will be a challenging task due to an overwhelming QCD background which gives rise to jets of particles that can be hard to distinguish from hadronic tau decays. Equipped with excellent tracking and calorimetry, the ATLAS experiment has developed tau identification tools capable of working at the trigger level. This contribution presents tau trigger algorithms which exploit the main features of hadronic tau decays and describes the current tau trigger commissioning activities. Many of the SM processes being investigated at ATLAS, as well as numerous BSM searches, contain tau leptons in their final states. Being able to trigger effectively on the tau leptons in these events will contribute to the success of the ATLAS experiment. The tau trigger algorithms and monitoring infrastructure are ready for the first data, and are being tested with the data collected with cosmic muons. The development of efficiency measurements methods using QCD and Z {yields} {tau}{tau} events is well advanced.

Benslama, K.; Kalinowski, A.; /Regina U.; Belanger-Champange, C.; Brenner, R.; /Uppsala U.; Bosman, M.; Casado, P.; Osuna, C.; Perez, E.; Vorwerk, V.; /Barcelona, IFAE; Czyczula, Z.; Dam, M.; Xella, S.; /Copenhagen U.; Demers, S.; /SLAC; Farrington, S.; /Oxford U.; Igonkina, O.; /NIKHEF, Amsterdam; Kanaya, N.; Tsuno, S.; /Tokyo U.; Ptacek, E.; Reinsch, A.; Strom, David M.; Torrence, E.; /Oregon U. /Sydney U. /Lancaster U. /Birmingham U.

2011-11-09T23:59:59.000Z

74

Tau Physics 2006: Summary & Outlook  

E-Print Network (OSTI)

A large amount of new results have been presented at TAU2006. The highlights of the workshop, the present status of a few selected topics on lepton physics (universality, QCD tests, Vus determination from ? decay, g ? 2, ? oscillations, lepton-flavour violation) and the prospects for future improvements are briefly summarized. 1.

A. Pich A

2007-01-01T23:59:59.000Z

75

Neutrinos' Instant Identity Changes Could Mean Big Things for the Big Bang  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Neutrinos' Instant Identity Changes Could Mean Big Things for the Neutrinos' Instant Identity Changes Could Mean Big Things for the Big Bang Neutrinos' Instant Identity Changes Could Mean Big Things for the Big Bang July 11, 2011 - 12:23pm Addthis Scientists use the near detector to verify the intensity and purity of the muon neutrino beam leaving the Fermilab site. | Courtesy of Fermilab, photo by Peter Ginter Scientists use the near detector to verify the intensity and purity of the muon neutrino beam leaving the Fermilab site. | Courtesy of Fermilab, photo by Peter Ginter Charles Rousseaux Charles Rousseaux Senior Writer, Office of Science What are the key facts? Researchers at Fermilab have been studying neutrinos and how they might change, or oscillate, between their three different identities -- electron, muon and tau.

76

Evidence for B+ --> tau+ nu_tau Decays using Hadronic B Tags  

SciTech Connect

We present a search for the decay B{sup +} --> {tau}{sup +} {nu}{sub {tau}} using 467.8 x 10{sup 6} B{anti B} pairs collected at the {Upsilon}(4S) resonance with the BABAR detector at the SLAC PEP-II B-Factory. We select a sample of events with on completely reconstructed B{sup -} in an hadronic decay mode (B{sup -} --> D{sup (*)0}X{sup -} and B{sup -} --> J/{psi} X{sup -}). We examine the rest of the event to search for a B{sup +} --> {tau}{sup +} {nu}{sub {tau}} decay. We identify the {tau}{sup +} lepton in the following modes: {tau}{sup +} --> e{sup +} {nu}{sub e}{anti {nu}}{sub {tau}}, {tau}{sup +} --> {mu}{sup +} {nu}{sub {mu}}{anti {nu}}{sub {tau}}, {tau}{sup +} --> {pi}{sup +}{anti {nu}}{sub {tau}} and {tau}{sup +} --> {rho}{anti {nu}}{sub {tau}}. We find an excess of events with respect to expected background, which excludes the null signal hypothesis at the level of 3.3 {sigma} and can be converted to a branching fraction central value of B(B{sup +} --> {tau}{sup +} {nu}{sub {tau}})= (1.80{sup + 0.57}{sub - 0.54}(stat.) {+-} 0.26 (syst.)) x 10{sup -4}.

del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; Milanes, D.A.; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; /UC, Berkeley; Koch, H.; Schroeder, T.; /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Indian Inst. Tech., Guwahati /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

2011-08-11T23:59:59.000Z

77

Precision Measurements of Tau Lepton Decays  

SciTech Connect

Using data collected with the BABAR detector at the SLAC PEP-II electron-positron storage ring operating at a center-of-mass energy near 10.58 GeV, the branching fractions {Beta}({tau}{sup -} {yields} {pi}{sup -}{pi}{sup -}{pi}{sup +}{nu}{sub {tau}}) = (8.83 {+-} 0.01 {+-} 0.13)%, {Beta}({tau}{sup -} {yields} K{sup -}{pi}{sup -}{pi}{sup +}{nu}{sub {tau}}) = (0.273 {+-} 0.002 {+-} 0.009)%, {Beta}({tau}{sup -} {yields} K{sup -}{pi}{sup -}K{sup +}{nu}{sub {tau}}) = (0.1346 {+-} 0.0010 {+-} 0.0036)%, and {Beta}({tau}{sup -} {yields} K{sup -}K{sup -}K{sup +}{nu}{sub {tau}}) = (1.58 {+-} 0.13 {+-} 0.12) x 10{sup -5} are measured where the uncertainties are statistical and systematic, respectively. The invariant mass distribution for the {tau}{sup -} {yields} {pi}{sup -}{pi}{sup -}{pi}{sup +}{nu}{sub {tau}} {yields} K{sup -}{pi}{sup -}{pi}{sup +}{nu}{sub {tau}}, {tau}{sup -} {yields} K{sup -}{pi}{sup -}K{sup +}{nu}{sub {tau}} and {tau}{sup -} {yields} K{sup -}K{sup -}K{sup +}{nu}{sub {tau}} decays are unfolded to correct for detector effects. A measurement of {Beta}({tau}{sup -} {yields} {phi}{pi}{sup -}{nu}{sub {tau}}) = (3.42 {+-} 0.55 {+-} 0.25) x 10{sup -5}, a measurement of {Beta}({tau}{sup -} {yields} {phi}K{sup -}{nu}{sub {tau}}) = (3.39 {+-} 0.20 {+-} 0.28) x 10{sup -5} and an upper limit on {Beta}({tau}{sup -} {yields} K{sup -}K{sup -}K{sup +}{nu}{sub {tau}}[ex.{phi}]) {le} 2.5 x 10{sup -6} {at} 905 CL are determined from a binned maximum likelihood fit of the {tau}{sup -} {yields} K{sup -}{pi}{sup -}K{sup +}{nu}{sub {tau}} and {tau}{sup -} {yields} K{sup -}K{sup -}K{sup +}{nu}{sub {tau}} K{sup +}K{sup -} invariant mass distributions. The branching ratio {Beta}({tau}{sup -} {yields} K{sup -}{nu}{sub {tau}})/{Beta}({tau}{sup -} {yields} {pi}{sup -}{nu}{sub {tau}}) is measured to be (6.531 {+-} 0.056 {+-} 0.093) x 10{sup -2} from which |V{sub us}| is determined to be 0.2255 {+-} 0.0023. The branching ratio {Beta}/({tau}{sup -} {yields} {mu}{nu}{sub {tau}}{bar {nu}}{sub {mu}})/{Beta}({tau}{sup -} {yields} e{sup -} {nu}{sub {tau}}{bar {nu}}{sub e}) = (9.796 {+-} 0.016 {+-} 0.035) x 10{sup -1} is measured enabling a precision test of the Standard Model assumption of charged current lepton universality, g{sub {mu}}/g{sub e} = 1.0036 {+-} 0.0020. The branching ratios {Beta}({tau}{sup -} {yields} K{sup -}{nu}{sub {tau}})/{Beta}({tau}{sup -} {yields} e{sup -}{nu}{sub {tau}}{bar {nu}}{sub e}) = (3.882 {+-} 0.032 {+-} 0.057) x 10{sup -2}, and {Beta}({tau}{sup -} {yields} {pi}{sup -}{nu}{sub {tau}})/{Beta}({tau}{sup -} {yields} e{nu}{sub {tau}}{bar {nu}}{sub e}) = (5.9545 {+-} 0.014 {+-} 0.061) x 10{sup -1} are measured which provide additional tests of charged current lepton universality, (g{sub {tau}}/g{sub {mu}}){sub {pi}} = 0.9856 {+-} 0.0057 and (g{sub {tau}}/g{sub {mu}}){sub K} = 0.9827 {+-} 0.0086 which can be combined to give (g{sub {tau}}/g{sub {mu}}){sub {pi}/K} = 0.9850 {+-} 0.0054. Any deviation of these measurements from the expected Standard Model values would be an indication of new physics.

Nugent, Ian M.; /Victoria U.

2010-03-16T23:59:59.000Z

78

A phenomenological outlook on three-flavor atmospheric neutrino oscillations  

E-Print Network (OSTI)

The recent observations of atmospheric nu events from the Super-Kamiokande experiment are compatible with three-flavor neutrino oscillations, occurring dominantly in the nu_munu_tau channel and subdominantly in the nu_munu_e channel. We present an updated analysis of the three-flavor mass-mixing parameters consistent with the present phenomenology, including the latest 45 kTy data sample from Super-Kamiokande. A comparison with our previous results, based on 33 kTy data, shows that the oscillation evidence is strengthened, and that the neutrino mass-mixing parameters are constrained in smaller ranges.

G. L. Fogli; E. Lisi; A. Marrone; G. Scioscia

1999-04-27T23:59:59.000Z

79

Neutrino dark matter candidate in fourth generation scenarios  

E-Print Network (OSTI)

We overview the constraints on the 4th-generation neutrino dark matter candidate and investigate a possible way to make it a viable dark matter candidate. Given the LEP constraints tell us that the 4th-generation neutrino has to be rather heavy (> M_Z/2), in sharp contrast to the other three neutrinos, the underlying nature of the 4th-generation neutrino is expected to be different. We suggest that an additional gauge symmetry B-4L_4 distinguishes it from the Standard Model's three lighter neutrinos and this also facilitates promotion of the 4th-generation predominantly right-handed neutrino to a good cold dark matter candidate. It provides distinguishable predictions for the dark matter direct detection and the Large Hadron Collider experiments.

Hye-Sung Lee; Zuowei Liu; Amarjit Soni

2011-05-17T23:59:59.000Z

80

Luminescent Bolometer and Neutrino Physics  

E-Print Network (OSTI)

The luminescent bolometer, proposed in 1988, is now seriously considered for several applications in nuclear and particle physics: dark matter searches, double beta decays, low energy neutrino physics, heavy ion physics... It is also a very promising device for basic condensed-matter physics and chemistry experiments, and may lead to astrophysical applications. The luminescent bolometer is based on the simultaneous detection of light and phonons, allowing for particle identification and for a detailed study of the detector response. Digitized analysis of the signals produced in several sensors installed on the same crystal is then a very powerful tool. Superconducting sensors allow to detect the scintillation light pulse followed by the delayed front of phonons, and can be extremely sensitive leading to single photon counting in the visible range. They also provide information on the position of the event inside the absorber, and can be fast enough for all proposed applications. The luminescent bolometer, with superconducting sensors, appears extremely promising for real time $solar$ neutrino experiments based on new indium single crystal scintillators. We focus on this particular application, discussing the status of the art as well as open problems and presenting an updated description of a full scale real time solar neutrino experiment sensitive to the low energy sector. Other applications of the luminescent bolometer (e.g. spectroscopy or neutrino detection at reactors), involving indium compounds and other single crystal scintillators, are equally considered and discussed in detail.

Luis Gonzalez-Mestres

1997-11-25T23:59:59.000Z

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81

Solar Neutrinos in 2011  

E-Print Network (OSTI)

I give an overview of the recent developments in the solar neutrino field. I focus on the Borexino detector, which has uncovered the solar neutrino spectrum below 5 MeV, providing new tests and confirmation for solar neutrino oscillations. I report on the updated measurements of the 8B solar neutrino flux by water Cherenkov and organic scintillator detectors. I review the precision measurement of the 7Be solar neutrino flux by Borexino and the search for its day-night asymmetry. I present Borexino's latest result on the study of pep and CNO neutrinos. Finally, I discuss the outstanding questions in the field and future solar neutrino experiments.

Chavarria, Alvaro

2012-01-01T23:59:59.000Z

82

Light sterile neutrinos, spin flavour precession and the solar neutrino experiments  

E-Print Network (OSTI)

We generalize to three active flavours a previous two flavour model for the resonant spin flavour conversion of solar neutrinos to sterile ones, a mechanism which is added to the well known LMA one. The transition magnetic moments from the muon and tau neutrinos to the sterile play the dominant role in fixing the amount of active flavour suppression. We also show, through numerical integration of the evolution equations, that the data from all solar neutrino experiments except Borexino exhibit a clear preference for a sizable magnetic field either in the convection zone or in the core and radiation zone. This is possibly related to the fact that the data from the first set are average ones taken during a period of mostly intense solar activity, whereas in contrast Borexino data were taken during a period of quiet sun. We argue that the solar neutrino experiments are capable of tracing the possible modulation of the solar magnetic field. Those monitoring the high energy neutrinos, namely the $^8 B$ flux, appear to be sensitive to a field modulation either in the convection zone or in the core and radiation zone. Those monitoring the low energy fluxes will be sensitive to the second type of solar field profiles only. In this way Borexino alone may play an essential role, since it examines both energy sectors, although experimental redundance from other experiments will be most important.

C. R. Das; Joao Pulido; Marco Picariello

2009-02-09T23:59:59.000Z

83

Observation of Tau Decays with Two Neutral Kaons  

E-Print Network (OSTI)

We report on the observation of the decay \\Gamma ! K 0 K 0 \\Gamma in 3.11 fb \\Gamma1 of data taken with the CLEO II detector at the Cornell Electron Storage Ring. Both K 0 mesons are detected through their decays via K S ! + \\Gamma . Preliminary results on the branching fraction and on the resonant substructure are presented. In particular, we find B( \\Gamma ! K 0 K 0 \\Gamma ) = 0:083 \\Sigma 0:017 \\Sigma 0:017 %. We also comment on the sensitivity of the KK invariant mass spectrum to a non-zero tau-neutrino mass. Permanent address: University of Hawaii at Manoa y Permanent address: INP, Novosibirsk, Russia 2 I. INTRODUCTION Tau lepton decays of the type \\Gamma ! [KK] \\Gamma have been known to exist [1] for nearly a decade. However, due to the small decay width and difficulties associated with identifying kaons, little information is presently available for these decays. In this paper, we report on the observation of KK decays where both...

Balest Cho Ford; Ichep Ref; Gsl Cleo Conf; K. Cho; K. Lingel; M. Lohner; P. Rankin

1994-01-01T23:59:59.000Z

84

Lepton flavour violating Higgs Boson decays, tau --> mu gamma and B(s) --> mu+mu- in the constrained MSSM+NR with large tan beta  

E-Print Network (OSTI)

Realistic predictions are made for the rates of lepton flavour violating Higgs boson decays, tau --> mu gamma, mu --> e gamma, Bs --> mu+mu-, Bs --> tau mu and tau --> 3mu, via a top-down analysis of the Minimal Supersymmetric Standard Model(MSSM) constrained by SU(5) unification with right-handed Neutrinos and large tan beta. The third family neutrino Yukawa coupling is chosen to be of order 1, in this way our model bares a significant resemblance to supersymmetric SO(10). In this framework the large PMNS mixings result in potentially large lepton flavour violation. Our analysis predicts tau --> mu gamma and mu --> e gamma rates in the region (10^{-8}-10^{-6}) and (10^{-15}-10^{-14}) respectively. We also show that the rates for lepton flavour violating Higgs decays can be as large as 10^{-7}. The non-decoupling nature of H --> tau mu is observed which leads to its decay rate becoming comparable to that for tau --> mu gamma for large values of m_0 and M_1/2. We also find that the present bound on Bs --> mu+mu- is an important constraint on the rate of lepton flavour violating Higgs decays. The recently measured Bs-Bsbar mixing parameter Delta Ms is also investigated.

J. K. Parry

2005-10-24T23:59:59.000Z

85

STANDARD SOLAR NEUTRINOS  

E-Print Network (OSTI)

The predictions of an improved standard solar model are compared with the observations of the four solar neutrino experiments. The improved model includes premain sequence evolution, element diffusion, partial ionization effects, and all the possible nuclear reactions between the main elements. It uses updated values for the initial solar element abundances, the solar age, the solar luminosity, the nuclear reaction rates and the radiative opacities. Neither nuclear equilibrium, nor complete ionization are assumed. The calculated 8 B solar neutrino flux is consistent, within the theoretical and experimental uncertainties, with the solar neutrino flux measured by Kamiokande. The results from the 37 Cl and 71 Ga radiochemical experiments seem to suggest that the terrestrial 7 Be solar neutrino flux is much smaller than that predicted. However, the present terrestrial defecit of 7 Be solar neutrinos may be due to the use of inaccurate theoretical neutrino absorption cross sections near threshold for extracting solar neutrino fluxes from production rates. Conclusive evidence for a real deficit of 7 Be solar neutrinos will require experiments such as BOREXINO or HELLAZ. A real defecit of 7 Be solar neutrinos can be due to either astrophysical reasons or neutrino properties beyond the standard electroweak model. Only future neutrino experiments, such as SNO, Superkamiokande, BOREXINO and HELLAZ, will be able to provide conclusive evidence that the solar neutrino problem is a consequence of neutrino properties beyond the standard electroweak model. Earlier indications may be provided by long baseline neutrino oscillation experiments. 1

Arnon Dar

2008-01-01T23:59:59.000Z

86

Electric dipole moments, from e to tau  

E-Print Network (OSTI)

We derive an upper limit on the electric dipole moment (EDM) of the tau-lepton, which follows from the precision measurements of the electron EDM.

Grozin, A G; Rudenko, A S

2008-01-01T23:59:59.000Z

87

B to tau Leptonic and Semileptonic Decays  

Science Conference Proceedings (OSTI)

Decays of B mesons to states involving {tau} leptons can be used as a tool to search for the effects of new physics, such as those involving a charged Higgs boson. The experimental status of the decays B {yields} {tau}{nu} and B {yields} D{sup (*)}{tau}{nu} is discussed, together with limits on new physics effects from current results. Leptonic and semileptonic decays of B mesons into states involving {tau} leptons remain experimentally challenging, but can prove a useful tool for constraining Standard Model parameters, and also offer to constrain the effects of any new physics that may exist including the presence of a charged Higgs boson.

Barrett, M.; /Brunel U.

2011-11-17T23:59:59.000Z

88

Neutrino mass, a status report  

SciTech Connect

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.

Robertson, R.G.H.

1993-08-01T23:59:59.000Z

89

Experimental Neutrino Physics: Final Report  

Science Conference Proceedings (OSTI)

Experimental studies of neutrino properties, with particular emphasis on neutrino oscillation, mass and mixing parameters. This research was pursued by means of underground detectors for reactor anti-neutrinos, measuring the flux and energy spectra of the neutrinos. More recent investigations have been aimed and developing detector technologies for a long-baseline neutrino experiment (LBNE) using a neutrino beam from Fermilab.

Lane, Charles E.; Maricic, Jelena

2012-09-05T23:59:59.000Z

90

Neutrino Nucleosynthesis in Supernovae  

Science Conference Proceedings (OSTI)

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

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

2009-05-04T23:59:59.000Z

91

Selected Topics in Tau Physics from BaBar  

SciTech Connect

Selected results from {tau} analyses performed using the BABAR detector at the SLAC National Accelerator Laboratory are presented. A precise measurement of the {tau} mass and the {tau}{sup +}{tau}{sup -} mass difference is undertaken using the hadronic decay mode {tau}{sup {+-}} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup {+-}}{nu}{sub {tau}}. In addition an investigation into the strange decay modes {tau}{sup -} {yields} K{sub S}{sup 0}{pi}{sup -}{pi}{sup 0}{nu}{sub {tau}} and {tau}{sup -} {yields} K{sub S}{sup 0}{pi}{sup -}{nu}{sub {tau}} is also presented, including a fit to the {tau}{sup -} {yields} K{sub S}{sup 0}{pi}{sup -}{nu}{sub {tau}} invariant mass spectrum. Precise values for M(K*(892)) and {Lambda}(K*(892)) are obtained.

Paramesvaran, S.; /Royal Holloway, U. of London

2012-04-06T23:59:59.000Z

92

BNL | Neutrino Research History  

NLE Websites -- All DOE Office Websites (Extended Search)

Brookhaven Neutrino Research Brookhaven Neutrino Research image of neutrinos Tens of billions of neutrinos are passing through every square centimeter of the Earth's surface right now. A Ghost-Particle Retrospective Neutrinos, ghostlike particles that flooded the universe just moments after the Big Bang, are born in the hearts of stars and other nuclear reactions. Untouched by electromagnetism and nearly as fast as light, neutrinos pass practically unhindered through everything from planets to people, only rarely responding to the weak nuclear force and the even weaker gravity. In fact, at any given moment, tens of billions of neutrinos are passing through every square centimeter of the Earth's surface. Neutrino Research News photomultiplier tubes New Results from Daya Bay: Tracking the Disappearance of Ghostlike

93

Outlook on Neutrino Physics  

E-Print Network (OSTI)

Some of the hot topics in neutrino physics are discussed, with particular emphasis on neutrino oscillations. After proposing credibility criteria for assessing various claimed effects, particular stress is laid on the solar neutrino deficit, which seems unlikely to have an astrophysical explanation. Comments are also made on the possibility of atmospheric neutrino oscillations and on the LSND experiment, as well as cosmological aspects of neutrinos and neutralinos. Several of the central issues in neutrino physics may be resolved by the new generation of experiments now underway, such as CHORUS, NOMAD and Superkamiokande, and in preparation, such as SNO and a new round of accelerator- and reactor-based neutrino-oscillation experiments. At the end, there is a brief review of ways in which present and future CERN experiments may be able to contribute to answering outstanding questions in neutrino physics.

John Ellis

1996-11-29T23:59:59.000Z

94

Measurement of tau lepton branching fractions  

SciTech Connect

We present {tau}{sup {minus}} lepton branching fraction measurements based on data from the TPC/Two-Gamma detector at PEP. Using a sample of{tau}{sup {minus}} {yields} {nu}{sub {tau}}K{sup {minus}}{pi}{sup +}{pi}{sup {minus}} events, we examine the resonance structure of the K{sup {minus}}{pi}{sup +}{pi}{sup {minus}} system and obtain the first measurements of branching fractions for {tau}{sup {minus}} {yields} {nu}{sub {tau}}K{sub 1}{sup {minus}}(1270) and {tau}{sup {minus}} {yields} {nu}{sub {tau}}K{sub 1}{sup {minus}}(1400). We also describe a complete set of branching fraction measurements in which all the decays of the {tau}{sup {minus}} lepton are separated into classes defined by the identities of the charged particles and an estimate of the number of neutrals. This is the first such global measurement with decay classes defined by the four possible charged particle species, e, {mu}, {pi}, and K.

Nicol, N.A.

1993-09-30T23:59:59.000Z

95

Neutrino-electron scattering in a magnetic field with allowance for polarizations of electrons  

Science Conference Proceedings (OSTI)

We present an analytic formula for differential cross section (DCS) of neutrino-electron scattering (NES) in a magnetic field (MF) with allowance for longitudinal polarizations of initial and final electrons (IAFE). The DCS of NES in a MF is sensitive to the spin variable of the IAFE and to the direction of the incident and scattered neutrinos (IASN) momenta. Spin asymmetries and field effects in NES in a MF enable us to use initial electrons having a left-hand circular polarization (LHCP) as polarized electron targets in detectors for detection of low-energy neutrinos or relic neutrinos and for distinguishing neutrino flavor (NF). In general, gas consisting of only electrons having a LHCP and gas consisting of only electrons having a right-hand circular polarization (RHCP) are heated by neutrinos asymmetrically. The asymmetry of heating (AH) is sensitive to NF, MF strength, energies (Landau quantum numbers and third components of the momenta) of IAFE, final electron chemical potential, the final temperature of gas consisting of only electrons having a LHCP (RHCP), polar angles of IASN momenta, the difference between the azimuthal angles of IASN momenta, the angle {phi}, and IASN energies. In the heating process of electrons by neutrinos the dominant role belongs to electron neutrinos compared with the contribution of muon (tauon) neutrinos. Electrons having a LHCP in NES in a MF are heated by {nu}{sub e} and {nu}{sub {mu}}({nu}{sub {tau}}) unequally when both the IASN fly along or against the MF direction. For magnetars and neutrinos of 1 MeV energy, within the considered kinematics, the AH in an electron neutrino-electron scattering is 2.23 times that in a muon neutrino-electron scattering or in a tauon neutrino-electron scattering.

Guseinov, V. A. [Department of General and Theoretical Physics, Nakhchivan State University, AZ 7000, Nakhchivan (Azerbaijan); Laboratory of Physical Research, Nakhchivan Division of Azerbaijan National Academy of Sciences, AZ 7000, Nakhchivan (Azerbaijan); Jafarov, I. G. [Department of Theoretical Physics and Astrophysics, Azerbaijan State Pedagogical University, Baku (Azerbaijan); Gasimova, R. E. [Department of General and Theoretical Physics, Nakhchivan State University, AZ 7000, Nakhchivan (Azerbaijan)

2007-04-01T23:59:59.000Z

96

Neutrino Oscillation Physics  

Science Conference Proceedings (OSTI)

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. Neutrinos and photons are by far the most abundant elementary particles in the universe. Thus, if we would like to comprehend the universe, we must understand the neutrinos. Of course, studying the neutrinos is challenging, since the only known forces through which these electrically-neutral leptons interact are the weak force and gravity. Consequently, interactions of neutrinos in a detector are very rare events, so that very large detectors and intense neutrino sources are needed to make experiments feasible. Nevertheless, we have confirmed that the weak interactions of neutrinos are correctly described by the Standard Model (SM) of elementary particle physics. Moreover, in the last 14 years, we have discovered that neutrinos have nonzero masses, and that leptons mix. These discoveries have been based on the observation that neutrinos can change from one 'flavor' to another - the phenomenon known as neutrino oscillation. We shall explain the physics of neutrino oscillation, deriving the probability of oscillation in a new way. We shall also provide a very brief guide to references that can be used to study some major neutrino-physics topics other than neutrino oscillation.

Kayser, Boris

2012-06-01T23:59:59.000Z

97

Introduction to Neutrino Physics  

SciTech Connect

I present a basic introduction to the physics of the neutrino, with emphasis on experimental results and developments.

Linares, Edgar Casimiro [Division de Ciencias e Ingenierias Campus Leon, Loma del Bosque 103 Col. Lomas del Campestre, C.P. 37150 Leon (Mexico) and Centro de Investigaciones Energeticas Medioambientales y Tecnologicas, Av. Complutense, 22, C.P. 28040, Madrid (Spain)

2009-04-30T23:59:59.000Z

98

Fundamental neutrino experiments  

E-Print Network (OSTI)

We review fundamental open problems in neutrino physics and propose two basic experiments for their possible resolution.

Ruggero Maria Santilli

2006-11-06T23:59:59.000Z

99

Revising the solution of the neutrino oscillation parameter degeneracies at neutrino factories  

SciTech Connect

In the context of neutrino factories, we review the solution of the degeneracies in the neutrino oscillation parameters. In particular, we have set limits to sin{sup 2}2{theta}{sub 13} in order to accomplish the unambiguous determination of {theta}{sub 23} and {delta}. We have performed two different analysis. In the first, at a baseline of 3000 km, we simulate a measurement of the channels {nu}{sub e}{yields}{nu}{sub {mu}}, {nu}{sub e}{yields}{nu}{sub {tau}}, and {nu}{sub {mu}}{yields}{nu}{sub {mu}}, combined with their respective conjugate ones, with a muon energy of 50 GeV and a running time of five years. In the second, we merge the simulated data obtained at L=3000 km with the measurement of {nu}{sub e}{yields}{nu}{sub {mu}} channel at 7250 km, the so-called 'magic baseline.' In both cases, we have studied the impact of varying the {nu}{sub {tau}} detector efficiency-mass product ({epsilon}{sub {nu}{tau}xM{tau}}), at 3000 km, keeping unchanged the {nu}{sub {mu}} detector mass and its efficiency. At L=3000 km, we found the existence of degenerate zones, that correspond to values of {theta}{sub 13}, which are equal or almost equal to the true ones. These zones are extremely difficult to discard, even when we increase the number of events. However, in the second scenario, this difficulty is overcome, demonstrating the relevance of the 'magic baseline'. From this scenario, the best limits of sin{sup 2}2{theta}{sub 13}, reached at 3{sigma}, for sin{sup 2}2{theta}{sub 23}=0.95, 0.975, and 0.99 are: 0.008, 0.015, and 0.045, respectively, obtained at {delta}=0, and considering ({epsilon}{sub {nu}{tau}xM{tau}}){approx_equal}125, which is 5 times the initial efficiency-mass combination.

Gago, A. M.; Jones Perez, J. [Seccion Fisica, Departamento de Ciencias, Pontificia Universidad Catolica del Peru, Apartado 1761, Lima (Peru)

2007-02-01T23:59:59.000Z

100

Solar neutrino oscillations  

Science Conference Proceedings (OSTI)

The special properties of solar neutrinos that render this flux so uniquely important in searches for neutrino masses and flavor mixing are reviewed. The effects of matter, including density fluctuations and turbulence, on solar neutrino oscillations are explained through analogies with more familiar atomic physics phenomena.

Haxton, W.C.

1993-12-31T23:59:59.000Z

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101

Solar neutrino physics: Sensitivity to light dark matter particles  

E-Print Network (OSTI)

Neutrinos are produced in several neutrino nuclear reactions of the proton-proton chain and carbon-nitrogen-oxygen cycle that take place at different radius of the Sun's core. Hence, measurements of solar neutrino fluxes provide a precise determination of the local temperature. The accumulation of non-annihilating light dark matter particles (with masses between 5 GeV and 16 GeV in the Sun produces a change in the local solar structure, namely, a decrease in the central temperature of a few percent. This variation depends on the properties of the dark matter particles, such as the mass of the particle and its spin-independent scattering cross-section on baryon-nuclei, specifically, the scattering with helium, oxygen, and nitrogen among other heavy elements. This temperature effect can be measured in almost all solar neutrino fluxes. In particular, by comparing the neutrino fluxes generated by stellar models with current observations, namely 8B neutrino fluxes, we find that non-annihilating dark matter particles with a mass smaller than 10 GeV and a spin-independent scattering cross-section with heavy baryon-nuclei larger than 3 x 10^{-37} cm^-2 produce a variation in the 8B neutrino fluxes that would be in conflict with current measurements.

Ilidio Lopes; Joseph Silk

2013-09-29T23:59:59.000Z

102

Measurement of the $?_e$ and Total $^{8}$B Solar Neutrino Fluxes with the Sudbury Neutrino Observatory Phase I Data Set  

E-Print Network (OSTI)

This article provides the complete description of results from the Phase I data set of the Sudbury Neutrino Observatory (SNO). The Phase I data set is based on a 0.65 kt-year exposure of heavy water to the solar $^8$B neutrino flux. Included here are details of the SNO physics and detector model, evaluations of systematic uncertainties, and estimates of backgrounds. Also discussed are SNO's approach to statistical extraction of the signals from the three neutrino reactions (charged current, neutral current, and elastic scattering) and the results of a search for a day-night asymmetry in the $\

SNO Collaboration

2006-10-13T23:59:59.000Z

103

Neutrino Spectroscopy with Atoms and Molecules  

E-Print Network (OSTI)

We give a comprehensive account of our proposed experimental method of using atoms or molecules in order to measure parameters of neutrinos still undetermined; the absolute mass scale, the mass hierarchy pattern (normal or inverted), the neutrino mass type (Majorana or Dirac), and the CP violating phases including Majorana phases. There are advantages of atomic targets, due to the closeness of available atomic energies to anticipated neutrino masses, over nuclear target experiments. Disadvantage of using atomic targets, the smallness of rates, is overcome by the macro-coherent amplification mechanism. The atomic or molecular process we use is a cooperative deexcitation of a collective body of atoms in a metastable level |e> emitting a neutrino pair and a photon; |e> -> |g> + gamma + nu_i nu_j where nu_i's are neutrino mass eigenstates. The macro-coherence is developed by trigger laser irradiation. We discuss aspects of the macro-coherence development by setting up the master equation for the target quantum state and propagating electric field. With a choice of heavy target atom or molecule such as Xe or I_2 that has a large M1 x E1 matrix element between |e> and |g>, we show that one can determine three neutrino masses along with the mass hierarchy pattern by measuring the photon spectral shape. If one uses a target of available energy of a fraction of 1 eV, Majorana CP phases may be determined. Our master equation, when applied to E1 x E1 transition such as pH_2 vibrational transition Xv=1 -> 0, can describe explosive PSR events in which most of the energy stored in |e> is released within a few nanoseconds. The present paper is intended to be self-contained explaining some details related theoretical works in the past, and further reports new simulations and our ongoing experimental efforts of the project to realize the neutrino mass spectroscopy using atoms/molecules.

Atsushi Fukumi; Susumu Kuma; Yuki Miyamoto; Kyo Nakajima; Itsuo Nakano; Hajime Nanjo; Chiaki Ohae; Noboru Sasao; Minoru Tanaka; Takashi Taniguchi; Satoshi Uetake; Tomonari Wakabayashi; Takuya Yamaguchi; Akihiro Yoshimi; Motohiko Yoshimura

2012-11-21T23:59:59.000Z

104

Identifying heavy Higgs bosons  

SciTech Connect

Two techniques for identifying heavy Higgs bosons produced at SSC energies are discussed. In the first, the Higgs boson decays into ZZ, with one Z decaying into an e-pair or ..mu..-pair and the other into a neutrino pair. In the second, the production of the Higgs boson by WW fusion is tagged by detecting the quarks that produced the bremsstrahlung virtual W's. The associated Higgs decay is identified by one leptonic and one hadronic decay. Both methods appear capable of finding a heavy Higgs boson provided the SSC design parameters are achieved. 16 refs., 2 figs., 2 tabs.

Cahn, R.N.

1986-06-01T23:59:59.000Z

105

SNO: solving the mystery of the missing neutrinos  

DOE Green Energy (OSTI)

The end of an era came on 28 November 2006 when the Sudbury Neutrino Observatory (SNO) finally stopped data-taking after eight exciting years of discoveries. During this time the Observatory saw evidence that neutrinos, produced in the fusion of hydrogen in the solar core, change flavour while passing through the Sun on their way to the Earth. This observation explained the longstanding puzzle as to why previous experiments had seen fewer solar neutrinos than predicted and confirmed that these elusive particles have mass. Solar neutrinos were first detected in Ray Davis's radiochemical experiment in 1967, for which discovery he shared the 2002 Nobel Prize in Physics. Surprisingly he found only about a third of the number predicted from models of the Sun's output. This deficit, the so-called Solar Neutrino Problem, was confirmed by Kamiokande-II while other experiments saw related deficits of solar neutrinos. A possible explanation for this deficit, suggested by Gribov and Pontecorvo in 1969, was that some of the electron-type neutrinos, which are produced in the Sun, had ''oscillated'' into neutrinos that could not be detected in the Davis detector. The oscillation mechanism requires that neutrinos have non-zero mass. The unique advantage, which was pointed out by the late Herb Chen in 1985, of using heavy water (D{sub 2}O) to detect the neutrinos from {sup 8}B decays in the solar fusion process is that it enables both the number of electron-type and of all types of neutrinos to be measured. A comparison of the flux of electron-type neutrinos to that of all flavours could then reveal whether flavour transformation is the cause of the solar neutrino deficit. In heavy water neutrinos of all types can break a deuteron apart into its constituent proton and neutron (neutral-current reaction), while only electron-type neutrinos can change the deuteron into two protons and release an electron (charged-current reaction). SNO was designed by scientists from Canada, the USA and the UK to attain a detection rate of about 10 solar neutrinos per day using 1000 tonnes of heavy water. Neutrino interactions were detected by 9,456 photomultiplier tubes surrounding the heavy water, which was contained in a 12-m diameter acrylic sphere. This sphere was surrounded by 7000 tonnes of ultra-pure water to shield against radioactivity. Figure 1 shows the layout of the SNO detector, which is located about 2 km underground in Inco's Creighton nickel mine near Sudbury in Canada, to all but eliminate cosmic rays from reaching the detector. The pattern of hit photomultiplier tubes following the creation of an electron by an electron-type neutrino is shown in Figure 2.

Jelley, Nick; Poon, Alan

2007-03-30T23:59:59.000Z

106

Supernova neutrinos and nucleosynthesis  

E-Print Network (OSTI)

Observations of metal-poor stars indicate that at least two different nucleosynthesis sites contribute to the production of r-process elements. One site is responsible for the production of light r-process elements Zproduction of these elements. We explore this possibility by performing nucleosynthesis calculations based on long term Boltzmann neutrino transport simulations. They are based on an Equation of State that reproduces recent constrains on the nuclear symmetry energy. We predict that the early ejecta is neutron-rich with Ye ~ 0.48, it becomes proton rich around 4 s and reaches Ye = 0.586 at 9 s when our simulation stops. The nucleosynthesis in this model produces elements between Zn and Mo, including 92Mo. The elemental abundances are consistent with the observations of the metal-poor star HD 12263. For the elements between Ge and Mo, we produce mainly the neutron-deficient isotopes. This prediction can be confirmed by observations of isotopic abundances in metal-poor stars. No elements heavier than Mo (Z=42) and no heavy r-process elements are produced in our calculations.

G. Martnez-Pinedo; T. Fischer; L. Huther

2013-09-21T23:59:59.000Z

107

Electronic branching ratio of the. tau. lepton  

Science Conference Proceedings (OSTI)

Using data accumulated by the CLEO I detector operating at the Cornell Electron Storage Ring, we have measured the ratio {ital R}={Gamma}({tau}{r arrow}{ital e}{bar {nu}}{sub {ital e}}{nu}{sub {tau}})/{Gamma}{sub 1}, where {Gamma}{sub 1} is the {tau} decay rate to final states with one charged particle. We find {ital R}=0.2231{plus minus}0.0044{plus minus}0.0073 where the first error is statistical and the second is systematic. Together with the measured topological one-charged-particle branching fraction, this yields the branching fraction of the {tau} lepton to electrons, {ital B}{sub {ital e}}=0.192{plus minus}0.004{plus minus}0.006.

Ammar, R.; Baringer, P.; Coppage, D.; Davis, R.; Kelly, M.; Kwak, N.; Lam, H.; Ro, S.; Kubota, Y.; Lattery, M.; Nelson, J.K.; Perticone, D.; Poling, R.; Schrenk, S.; Wang, R.; Alam, M.S.; Kim, I.J.; Nemati, B.; Romero, V.; Sun, C.R.; Wang, P.; Zoeller, M.M.; Crawford, G.; Fulton, R.; Gan, K.K.; Kagan, H.; Kass, R.; Lee, J.; Malchow, R.; Morrow, F.; Sung, M.K.; Whitmore, J.; Wilson, P.; Butler, F.; Fu, X.; Kalbfleisch, G.; Lambrecht, M.; Skubic, P.; Snow, J.; Wang, P.; Bortoletto, D.; Brown, D.N.; Dominick, J.; McIlwain, R.L.; Miller, D.H.; Modesitt, M.; Shibata, E.I.; Schaffner, S.F.; Shipsey, I.P.J.; Battle, M.; Ernst, J.; Kroha, H.; Roberts, S.; Sparks, K.; Thorndike, E.H.; Wang, C.; Stroynowski, R.; Artuso, M.; Goldberg, M.; Haupt, T.; Horwitz, N.; Kennett, R.; Moneti, G.C.; Playfer, S.; Rozen, Y.; Rubin, P.; Skwarnicki, T.; Stone, S.; Thulasidas, M.; Yao, W.; Zhu, G.; Barnes, A.V.; Bartelt, J.; Csorna, S.E.; Jain, V.; Letson, T.; Mestayer, M.D.; Akerib, D.S.; Barish, B.; Chadha, M.; (CLEO Collaboration)

1992-06-01T23:59:59.000Z

108

Martin Perl and the Tau Lepton  

Office of Scientific and Technical Information (OSTI)

Martin Perl and the Tau Lepton Martin Perl and the Tau Lepton Resources with Additional Information 'Martin L. Perl, a professor at the Stanford Linear Accelerator Center (SLAC), [was] awarded the 1995 Nobel Prize in physics ... for his 1975 discovery of a new elementary particle known as the tau lepton. ... The tau lepton is a superheavy cousin of the electron, the carrier of electrical current in household appliances. The two particles are identical in all respects except that the tau is more than 3,500 times heavier than the electron and survives less than a trillionth of a second, whereas the electron is stable. Martin Perl Courtesy AIP Emilio Segrè Visual Archives, W.F. Meggers Gallery of Nobel Laureates In the mid-1970s, working at the Stanford Positron-Electron Asymmetric Ring (SPEAR) in collaboration with 30 other physicists from SLAC and Lawrence Berkeley National Laboratory, Perl began to find events recorded by the detector that could not be explained by any of the known subatomic particles. After more than a year of analysis, Perl was able to convince the rest of his research team that they were in fact observing a new and different type of elementary particle, which he named the 'tau'.

109

Solar neutrino detection  

SciTech Connect

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

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

2009-04-30T23:59:59.000Z

110

Solar neutrino detection  

E-Print Network (OSTI)

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

Lino Miramonti

2009-01-22T23:59:59.000Z

111

Spectroscopy of Solar Neutrinos  

E-Print Network (OSTI)

In the last years, liquid-scintillator detectors have opened a new window for the observation of low-energetic astrophysical neutrino sources. In 2007, the solar neutrino experiment Borexino began its data-taking in the Gran Sasso underground laboratory. High energy resolution and excellent radioactive background conditions in the detector allow the first-time spectroscopic measurement of solar neutrinos in the sub-MeV energy regime. The experimental results of the Beryllium-7 neutrino flux measurements as well as the prospects for the detection of solar Boron-8, pep and CNO neutrinos are presented in the context of the currently discussed ambiguities in solar metallicity. In addition, the potential of the future SNO+ and LENA experiments for high-precision solar neutrino spectroscopy will be outlined.

Michael Wurm; Franz von Feilitzsch; Marianne Goeger-Neff; Tobias Lachenmaier; Timo Lewke; Quirin Meindl; Randoplh Moellenberg; Lothar Oberauer; Walter Potzel; Marc Tippmann; Christoph Traunsteiner; Juergen Winter

2010-04-06T23:59:59.000Z

112

Tau longitudinal polarization in B{yields}D{tau}{nu} and its role in the search for the charged Higgs boson  

Science Conference Proceedings (OSTI)

We study the longitudinal polarization of the tau lepton in B{yields}D{tau}{nu} decay. After discussing possible sensitivities of {tau} decay modes to the {tau} polarization, we examine the effect of charged Higgs boson on the {tau} polarization in B{yields}D{tau}{nu}. We find a relation between the decay rate and the {tau} polarization, and clarify the role of the {tau} polarization measurement in the search for the charged Higgs boson.

Tanaka, Minoru; Watanabe, Ryoutaro [Department of Physics, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043 (Japan)

2010-08-01T23:59:59.000Z

113

Neutrinos from Gamma Ray Bursts  

E-Print Network (OSTI)

We show that the detection of neutrinos from a typical gamma ray burst requires a kilometer-scale detector. We argue that large bursts should be visible with the neutrino telescopes under construction. We emphasize the 3 techniques by which neutrino telescopes can perform this search: by triggering on i) bursts of muons from muon neutrinos, ii) muons from air cascades initiated by high energy gamma rays and iii) showers made by relatively low energy ($\\simeq 100\\,\\mev$) electron neutrinos. Timing of neutrino-photon coincidences may yield a measurement of the neutrino mass to order $10^{-5}$~eV, an interesting range in light of the solar neutrino anomaly.

F. Halzen; G. Jaczko

1996-02-07T23:59:59.000Z

114

NEUTRINOS, OLD AND NEW  

SciTech Connect

Results are reported from a series of experiments that led to the conclusion that neutrinos exist in 4 states. (C.H.)

Reines, F.

1963-08-30T23:59:59.000Z

115

Neutrino Factory Feasibility Study  

NLE Websites -- All DOE Office Websites (Extended Search)

Witherell's Letter (Postscript) Final Version of the Neutrino Source Study Report (PDF) Organization Chart (Postscript) Two Day Meeting at Fermilab on February 15-16, 2000...

116

Neutrino-nucleus interactions  

SciTech Connect

The study of neutrino oscillations has necessitated a new generation of neutrino experiments that are exploring neutrino-nuclear scattering processes. We focus in particular on charged-current quasi-elastic scattering, a particularly important channel that has been extensively investigated both in the bubble-chamber era and by current experiments. Recent results have led to theoretical reexamination of this process. We review the standard picture of quasi-elastic scattering as developed in electron scattering, review and discuss experimental results, and discuss additional nuclear effects such as exchange currents and short-range correlations that may play a significant role in neutrino-nucleus scattering.

Gallagher, H.; /Tufts U.; Garvey, G.; /Los Alamos; Zeller, G.P.; /Fermilab

2011-01-01T23:59:59.000Z

117

Phenomenology of neutrino oscillations  

Science Conference Proceedings (OSTI)

see that the statistical uncertainty is the least for the super-Kamioka (SK) water Cerenkov detector, which is thus presaging the era of precision neutrino physics.

118

Solar neutrino Research  

NLE Websites -- All DOE Office Websites (Extended Search)

the neutrino detector. The pioneering experiments conducted in the Homestake Mine, Lead, South Dakota, led to the awarding of the 2002 Nobel Prize in Physics to Raymond Davis,...

119

Search for pair production of the scalar top quark in muon plus tau final states  

SciTech Connect

We present a search for the pair production of scalar top quarks ({tilde t}{sub 1}), the lightest supersymmetric partners of the top quarks, in p{bar p} collisions at a center-of-mass energy of 1.96 TeV, using data corresponding to an integrated luminosity of 7.3 fb{sup -1} collected with the D0 experiment at the Fermilab Tevatron Collider. Each scalar top quark is assumed to decay into a b quark, a charged lepton, and a scalar neutrino ({tilde {nu}}). We investigate final states arising from {tilde t}{sub 1}{ovr {tilde t}{sub 1}} {yields} b{bar b}{mu}{tau}{tilde {nu}}{tilde {nu}} and {tilde t}{sub 1}{ovr {tilde t}{sub 1}} {yields} b{bar b}{tau}{tau}{tilde {nu}}{tilde {nu}}. With no significant excess of events observed above the background expected from the standard model, we set exclusion limits on this production process in the (M{sub {tilde t}{sub 1}}, M{sub {tilde {nu}}}) plane.

Abazov V. M.; Abbott B.; Acharya B. S.; Adams M.; Adams T.; Alexeev G. D.; Alkhazov G.; Alton A.; Alverson G.; Aoki M.; Askew A.; Asman B.; Atkins S.; Atramentov O.; Augsten K.; Avila C.; BackusMayes J.; Badaud F.; Bagby L.; Baldin B.; Bandurin D. V.; Banerjee S.; Barberis E.; Baringer P.; Barreto J.; Bartlett J. F.; Bassler U.; Bazterra V.; Bean A.; Begalli M.; Belanger-Champagne C.; Bellantoni L.; Beri S. B.; Bernardi G.; Bernhard R.; Bertram I.; Besancon M.; Beuselinck R.; Bezzubov V. A.; Bhat P. C.; Bhatia S.; Bhatnagar V.; Blazey G.; Blessing S.; Bloom K.; Boehnlein A.; Boline D.; Boos E. E.; Borissov G.; Bose T.; Brandt A.; Brandt O.; Brock R.; Brooijmans G.; Bross A.; Brown D.; Brown J.; Bu X. B.; Buehler M.; Buescher V.; Bunichev V.; Burdin S.; Burnett T. H.; Buszello C. P.; Calpas B.; Camacho-Perez E.; Carrasco-Lizarraga M. A.; Casey B. C. K.; Castilla-Valdez H.; Chakrabarti S.; Chakraborty D.; Chan K. M.; Chandra A.; Chapon E.; Chen G.; Chevalier-Thery S.; Cho D. K.; Cho S. W.; Choi S.; Choudhary B.; Cihangir S.; Claes D.; Clutter J.; Cooke M.; Cooper W. E.; Corcoran M.; Couderc F.; Cousinou M. -C.; Croc A.; Cutts D.; Das A.; Davies G.; de Jong S. J.; De La Cruz-Burelo E.; Deliot F.; Demina R.; Denisov D.; Denisov S. P.; Desai S.; Deterre C.; DeVaughan K.; Diehl H. T.; Diesburg M.; Ding P. F.; Dominguez A.; Dorland T.; Dubey A.; Dudko L. V.; Duggan D.; Duperrin A.; Dutt S.; Dyshkant A.; Eads M.; Edmunds D.; Ellison J.; Elvira V. D.; Enari Y.; Evans H.; Evdokimov A.; Evdokimov V. N.; Facini G.; Ferbel T.; Fiedler F.; Filthaut F.; Fisher W.; Fisk H. E.; Fortner M.; Fox H.; Fuess S.; Garcia-Bellido A.; Garcia-Guerra G. A.; Gavrilov V.; Gay P.; Geng W.; Gerbaudo D.; Gerber C. E.; Gershtein Y.; Ginther G.; Golovanov G.; Goussiou A.; Grannis P. D.; Greder S.; Greenlee H.; Greenwood Z. D.; Gregores E. M.; Grenier G.; Gris Ph.; Grivaz J. -F.; Grohsjean A.; Gruenendahl S.; Gruenewald M. W.; Guillemin T.; Gutierrez G.; Gutierrez P.; Haas A.; Hagopian S.; Haley J.; Han L.; Harder K.; Harel A.; Hauptman J. M.; Hays J.; Head T.; Hebbeker T.; Hedin D.; Hegab H.; Heinson A. P.; Heintz U.; Hensel C.; Heredia-De La Cruz I.; Herner K.; Hesketh G.; Hildreth M. D.; Hirosky R.; Hoang T.; Hobbs J. D.; Hoeneisen B.; Hohlfeld M.; Hubacek Z.; Hynek V.; Iashvili I.; Ilchenko Y.; Illingworth R.; Ito A. S.; Jabeen S.; Jaffre M.; Jamin D.; Jayasinghe A.; Jesik R.; Johns K.; Johnson M.; Jonckheere A.; Jonsson P.; Joshi J.; Jung A. W.; Juste A.; Kaadze K.; Kajfasz E.; Karmanov D.; Kasper P. A.; Katsanos I.; Kehoe R.; Kermiche S.; Khalatyan N.; Khanov A.; Kharchilava A.; Kharzheev Y. N.; Kohli J. M.; Kozelov A. V.; Kraus J.; Kulikov S.; Kumar A.; Kupco A.; Kurca T.; Kuzmin V. A.; Lammers S.; Landsberg G.; Lebrun P.; Lee H. S.; Lee S. W.; Lee W. M.; Lellouch J.; Li H.; Li L.; Li Q. Z.; Lietti S. M.; Lim J. K.; Lincoln D.; Linnemann J.; Lipaev V. V.; Lipton R.; Liu Y.; Lobodenko A.; Lokajicek M.; Lopes de Sa R.; Lubatti H. J.; Luna-Garcia R.; Lyon A. L.; Maciel A. K. A.; Mackin D.; Madar R.; Magana-Villalba R.; Malik S.; Malyshev V. L.; Maravin Y.; Martinez-Ortega J.; McCarthy R.; McGivern C. L.; Meijer M. M.; Melnitchouk A.; Menezes D.; Mercadante P. G.; Merkin M.; et al.

2012-04-20T23:59:59.000Z

120

Heavy flavor production from photons and hadrons  

Science Conference Proceedings (OSTI)

The present state of the production and observation of hadrons containing heavy quarks or antiquarks as valence constituents, in reactions initiated by real and (space-like) virtual photon or by hadron beams is discussed. Heavy flavor production in e/sup +/e/sup -/ annihilation, which is well covered in a number of recent review papers is not discussed, and similarly, neutrino production is omitted due to the different (flavor-changing) mechanisms that are involved in those reactions. Heavy flavors from spacelike photons, heavy flavors from real photons, and heavy flavors from hadron-hadron collisions are discussed. (WHK)

Heusch, C.A.

1982-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "tau neutrinos heavy" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Monte Carlo Neutrino Oscillations  

E-Print Network (OSTI)

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

James P. Kneller; Gail C. McLaughlin

2005-09-29T23:59:59.000Z

122

Neutrino Counter Nuclear Weapon  

E-Print Network (OSTI)

Radiations produced by neutrino-antineutrino annihilation at the Z0 pole can be used to heat up the primary stage of a thermonuclear warhead and can in principle detonate the device remotely. Neutrino-antineutrino annihilation can also be used as a tactical assault weapon to target hideouts that are unreachable by conventional means.

Alfred Tang

2008-05-26T23:59:59.000Z

123

SNO Data: Results from Experiments at the Sudbury Neutrino Observatory  

DOE Data Explorer (OSTI)

The Sudbury Neutrino Observatory (SNO) was built 6800 feet under ground, in INCO's Creighton mine near Sudbury, Ontario. SNO is a heavy-water Cherenkov detector that is designed to detect neutrinos produced by fusion reactions in the sun. It uses 1000 tonnes of heavy water, on loan from Atomic Energy of Canada Limited (AECL), contained in a 12 meter diameter acrylic vessel. Neutrinos react with the heavy water (D2O) to produce flashes of light called Cherenkov radiation. This light is then detected by an array of 9600 photomultiplier tubes mounted on a geodesic support structure surrounding the heavy water vessel. The detector is immersed in light (normal) water within a 30 meter barrel-shaped cavity (the size of a 10 story building!) excavated from Norite rock. Located in the deepest part of the mine, the overburden of rock shields the detector from cosmic rays. The detector laboratory is extremely clean to reduce background signals from radioactive elements present in the mine dust which would otherwise hide the very weak signal from neutrinos. (From http://www.sno.phy.queensu.ca/]

The SNO website provides access to various datasets. See also the SNO Image Catalog at http://www.sno.phy.queensu.ca/sno/images/ and computer-generated images of SNO events at http://www.sno.phy.queensu.ca/sno/events/ and the list of published papers.

124

Determining Reactor Neutrino Flux  

E-Print Network (OSTI)

Flux is an important source of uncertainties for a reactor neutrino experiment. It is determined from thermal power measurements, reactor core simulation, and knowledge of neutrino spectra of fuel isotopes. Past reactor neutrino experiments have determined the flux to (2-3)% precision. Precision measurements of mixing angle $\\theta_{13}$ by reactor neutrino experiments in the coming years will use near-far detector configurations. Most uncertainties from reactor will be canceled out. Understanding of the correlation of uncertainties is required for $\\theta_{13}$ experiments. Precise determination of reactor neutrino flux will also improve the sensitivity of the non-proliferation monitoring and future reactor experiments. We will discuss the flux calculation and recent progresses.

Cao, Jun

2011-01-01T23:59:59.000Z

125

Determining Reactor Neutrino Flux  

E-Print Network (OSTI)

Flux is an important source of uncertainties for a reactor neutrino experiment. It is determined from thermal power measurements, reactor core simulation, and knowledge of neutrino spectra of fuel isotopes. Past reactor neutrino experiments have determined the flux to (2-3)% precision. Precision measurements of mixing angle $\\theta_{13}$ by reactor neutrino experiments in the coming years will use near-far detector configurations. Most uncertainties from reactor will be canceled out. Understanding of the correlation of uncertainties is required for $\\theta_{13}$ experiments. Precise determination of reactor neutrino flux will also improve the sensitivity of the non-proliferation monitoring and future reactor experiments. We will discuss the flux calculation and recent progresses.

Jun Cao

2011-01-12T23:59:59.000Z

126

Mass Hierarchy via Mossbauer and Reactor Neutrinos  

E-Print Network (OSTI)

We show how one could determine the neutrino mass hierarchy with Mossbauer neutrinos and also revisit the question of whether the hierarchy can be determined with reactor neutrinos.

Stephen Parke; Hisakazu Minakata; Hiroshi Nunokawa; Renata Zukanovich Funchal

2008-12-10T23:59:59.000Z

127

A Search for B+ ---> tau+ neutrino(tau) recoiling against B- ---> D0 l- anti-nu(l) X  

SciTech Connect

The fundamental pursuit of physics has always been a deeper understanding of nature's workings. In the last fifty years this pursuit has culminated in a view of the universe as a complex tapestry woven from only a few fundamental particles and interactions. This description of the universe, the Standard Model of Particle Physics, has been highly successful at predicting the behavior of these particles and interactions. However, the model leaves many questions unanswered and the hope is that many precise tests of its predictions will yield inconsistencies, windows into new physical principles. The search for processes that are allowed by the Standard Model but inherently rare provides fruitful ground for such a test. The large sample of B mesons available from the PEP-II/BABAR B-factory furnishes an opportunity to test Standard Model predictions via rare B meson decay modes.

Sekula, Stephen Jacob; /Wisconsin U., Madison /SLAC

2005-05-06T23:59:59.000Z

128

Solar neutrinos: Probing the sun or neutrinos  

SciTech Connect

The decade of the 1990's should prove to be a landmark period for the study of solar neutrino physics. Current observations show 2-3 times fewer neutrinos coming from the sun than are theoretically expected. As we enter the decade, new experiments are poised to attempt and discover whether this deficit is a problem with our understanding of how the sun works, is a hint of new neutrino properties beyond those predicted by the standard model of particle physics, or perhaps a combination of both. This paper will review the current status of the field and point out how future measurements should help solve this interesting puzzle. 11 refs., 3 figs., 1 tab.

Wilkerson, J.F.

1991-01-01T23:59:59.000Z

129

Search for Second-Class Currents in tau- -> omega.pi-.nu_tau  

SciTech Connect

We report an analysis of {tau}{sup -} decaying into {omega}{pi}{sup -} {nu}{sub {tau}} with {omega} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0} using a data sample containing nearly 320 million {tau} pairs collected with the BABAR detector at the PEP-II B-Factory. We find no evidence for second-class currents and we set an upper limit of 0.69% at 90% confidence level for the fraction of second-class currents in this decay mode.

Aubert, B.

2009-04-22T23:59:59.000Z

130

The strong coupling from tau decays without prejudice  

E-Print Network (OSTI)

We review our recent determination of the strong coupling \\alpha_s from the OPAL data for non-strange hadronic tau decays. We find that \\alpha_s(m^2_\\tau) =0.325+-0.018 using fixed-order perturbation theory, and \\alpha_s(m^2_\\tau)=0.347+-0.025 using contour-improved perturbation theory. At present, these values supersede any earlier determinations of the strong coupling from hadronic tau decays, including those from ALEPH data.

Boito, Diogo; Jamin, Matthias; Mahdavi, Andisheh; Maltman, Kim; Osborne, James; Peris, Santiago

2012-01-01T23:59:59.000Z

131

Review of Recent Neutrino Physics Research  

E-Print Network (OSTI)

We review recent research in neutrino physics, including neutrino oscillations to test time reversal and CP symmetry violations, the measurement of parameters in the U matrix, sterile neutrino emission causing pulsar kicks, and neutrino energies in the neutrinosphere.

Leonard S. Kisslinger

2013-06-17T23:59:59.000Z

132

Reactor Neutrino Experiments  

E-Print Network (OSTI)

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

Jun Cao

2007-12-06T23:59:59.000Z

133

Solar Neutrino Measurements  

E-Print Network (OSTI)

A review of solar neutrino experiments is provided, including experimental measurements to date and proposed future measurements. Experiments to date have provided a clear determination that solar neutrinos are undergoing flavor transformation and that the dominant mechanism for this transformation is oscillation. The mixing parameters are well defined and limits are placed on sub-dominant modes. The measurements also provide strong confirmation of solar model calculations. New experiments under development will study neutrino oscillation parameters and sub-dominant modes with greater precision and will investigate solar fluxes further, concentrating primarily on the low energy pp, $^7$Be, pep and CNO reactions.

A. B. McDonald

2004-06-10T23:59:59.000Z

134

Low Energy Neutrino Measurements  

E-Print Network (OSTI)

Low Energy solar neutrino detection plays a fundamental role in understanding both solar astrophysics and particle physics. After introducing the open questions on both fields, we review here the major results of the last two years and expectations for the near future from Borexino, Super-Kamiokande, SNO and KamLAND experiments as well as from upcoming (SNO+) and planned (LENA) experiments. Scintillator neutrino detectors are also powerful antineutrino detectors such as those emitted by the Earth crust and mantle. First measurements of geo-neutrinos have occurred and can bring fundamental contribution in understanding the geophysics of the planet.

Davide D'Angelo

2012-11-22T23:59:59.000Z

135

Leptogenesis with Dirac Neutrinos  

E-Print Network (OSTI)

We describe a "neutrinogenesis" mechanism whereby, in the presence of right-handed neutrinos with sufficiently small pure Dirac masses, (B+L)-violating sphaleron processes create the baryon asymmetry of the Universe, even when B=L=0 initially. It is shown that the resulting neutrino mass constraints are easily fulfilled by the neutrino masses suggested by current experiments. We present a simple toy model which uses this mechanism to produce the observed baryon asymmetry of the Universe. (PostScript Errors corrected in latest Version).

Karin Dick; Manfred Lindner; Michael Ratz; David Wright

1999-07-30T23:59:59.000Z

136

Search for Charged Higgs Boson Decays of the Top Quark Using Hadronic tau Decays  

SciTech Connect

We present the result of a search for charged Higgs boson decays of the top quark, produced in p{bar p} collisions at {radical}s = 1.8 TeV. When the charged Higgs boson is heavy and decays to a {tau} lepton, which subsequently decays hadronically, the resulting events have a unique signature: large missing transverse energy and the low-charged-multiplicity {tau}. Data collected in 1992 and 1993 at the Collider Detector at Fermilab, corresponding to 18.7 {+-} 0.7 pb{sup -1}, exclude new regions of combined top quark and charged Higgs boson mass, in extensions to the standard model with two Higgs doublets.

Abe, F.

1996-01-01T23:59:59.000Z

137

Solar Neutrino Measurements  

E-Print Network (OSTI)

Abstract. A review of solar neutrino experiments is provided, including experimental measurements to date and proposed future measurements. Experiments to date have provided a clear determination that solar neutrinos are undergoing flavor transformation and that the dominant mechanism for this transformation is oscillation. The mixing parameters are well defined and limits are placed on subdominant modes. The measurements also provide strong confirmation of solar model calculations. New experiments under development will study neutrino oscillation parameters and sub-dominant modes with greater precision and will investigate solar fluxes further, concentrating primarily on the low energy pp, 7Be, pep and CNO reactions. PACS numbers: 26.65+t, 95.55.Vj, 95.85.Ry, 96.60.Vg, 14.60.PqSolar Neutrino Measurements 2 1.

A. B. Mcdonald

2004-01-01T23:59:59.000Z

138

Fast Light, Fast Neutrinos?  

E-Print Network (OSTI)

Light has been observed with group velocities both faster and slower than the speed of light. The recent report from OPERA of superluminal 17 GeV neutrinos may describe a similar phenomenon.

Cahill, Kevin

2011-01-01T23:59:59.000Z

139

SOLAR NEUTRINOS. II. EXPERIMENTAL  

SciTech Connect

A method is described for observing solar neutrinos from the reaction Cl/ sup 37/( nu ,e/sup -/)Ar/sup 37/ in C/sub 2/Cl/sub 4/. Two 5 00-gal tanks of C/ sub 2/Cl/sub 4/ were placed in a limestone mine (1800 m.w.e.) and the resulting Ar/sup 37/ activity induced by cosmic mesons( mu ) was measured to determine the necessary conditions for solar neutrino observations. (R.E.U.)

Davis, R. Jr.

1964-03-16T23:59:59.000Z

140

Radiochemical solar neutrino experiments  

E-Print Network (OSTI)

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

V. N. Gavrin; B. T. Cleveland

2007-03-06T23:59:59.000Z

Note: This page contains sample records for the topic "tau neutrinos heavy" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Tuning and Analysis Utilities (TAU) | Argonne Leadership Computing Facility  

NLE Websites -- All DOE Office Websites (Extended Search)

Data Storage & File Systems Data Storage & File Systems Compiling & Linking Queueing & Running Jobs Data Transfer Debugging & Profiling Performance Tools & APIs Tuning MPI on BG/Q Tuning and Analysis Utilities (TAU) HPCToolkit HPCTW mpiP gprof Profiling Tools Darshan PAPI BG/Q Performance Counters BGPM Openspeedshop Scalasca BG/Q DGEMM Performance Software & Libraries IBM References Intrepid/Challenger/Surveyor Tukey Eureka / Gadzooks Policies Documentation Feedback Please provide feedback to help guide us as we continue to build documentation for our new computing resource. [Feedback Form] Tuning and Analysis Utilities (TAU) References TAU Project Site TAU Instrumentation Methods TAU Compilation Options TAU Fortran Instrumentation FAQ TAU Leap to Petascale 2009 Presentation

142

Lepton flavour violating Higgs and tau to mu gamma  

E-Print Network (OSTI)

We update phenomenological constraints on a Two Higgs Doublet Model with lepton flavour non-conserving Yukawa couplings. We review that $\\tan \\beta$ is ambiguous in such "Type III" models, and define it from the $\\tau$ Yukawa coupling. The neutral scalars $\\phi$ could be searched for at hadron colliders in $ \\phi \\to \\tau \\bar{\\mu}$, and are constrained by the rare decay $\\tau \\to \\mu \\gamma$. The Feynman diagrams for the collider process, with Higgs production via gluon fusion, are similar to the two-loop "Barr-Zee" diagrams which contribute to $\\tau \\to \\mu \\gamma$. Some "tuning" is required to obtain a collider cross-section of order the Standard Model expectation for $\\sigma (gg \\to h_{SM} \\to \\tau^+ \\tau^-)$, while agreeing with the current bound from $\\tau \\to \\mu \\gamma$.

Sacha Davidson; Gerald Grenier

2010-01-04T23:59:59.000Z

143

Sterile Neutrino Fits to Short-Baseline Neutrino Oscillation Measurements  

E-Print Network (OSTI)

This paper reviews short-baseline oscillation experiments as interpreted within the context of one, two, and three sterile neutrino models associated with additional neutrino mass states in the ~1?eV range. Appearance and ...

Conrad, J. M.

2013-01-01T23:59:59.000Z

144

Neutrino oscillations in nuclear media  

E-Print Network (OSTI)

On basis of effective interactions of charged lepton and hadron currents, we obtain an effective interacting Hamiltonian of neutrinos in nuclear media up to the leading order. Using this effective Hamiltonian, we study neutrino mixing and oscillations in nuclear media and strong magnetic fields. We compute neutrino mixing angle and mass squared difference, and find the pattern of vacuum neutrino oscillations is modified in magnetized nuclear media. Comparing with the vacuum neutrino oscillation, we find that for high-energy neutrinos, neutrino oscillations are suppressed in the presence of nuclear media. In the general case of neutral nuclear media with the presence of electrons, we calculate the mixing angle and mass squared difference, and discuss the resonance and level-crossing in neutrino oscillations.

Iman Motie; She-Sheng Xue

2011-04-14T23:59:59.000Z

145

How do Uncertainties in the Surface Chemical Abundances of the Sun Affect the Predicted Solar Neutrino Fluxes?  

E-Print Network (OSTI)

We show that uncertainties in the values of the surface heavy element abundances of the Sun are the largest source of the theoretical uncertainty in calculating the p-p, pep, 8B, 13N, 15O, and 17F solar neutrino fluxes. We evaluate for the first time the sensitivity (partial derivative) of each solar neutrino flux with respect to the surface abundance of each element. We then calculate the uncertainties in each neutrino flux using `conservative (preferred)' and `optimistic' estimates for the uncertainties in the element abundances. The total conservative (optimistic) composition uncertainty in the predicted 8B neutrino flux is 11.6% (5.0%) when sensitivities to individual element abundances are used. The traditional method that lumps all abundances into a single quantity (total heavy element to hydrogen ratio, Z/X) yields a larger uncertainty, 20%. The uncertainties in the carbon, oxygen, neon, silicon, sulphur, and iron abundances all make significant contributions to the uncertainties in calculating solar neutrino fluxes; the uncertainties of different elements are most important for different neutrino fluxes. The uncertainty in the iron abundance is the largest source of the estimated composition uncertainties of the important 7Be and 8B solar neutrinos. Carbon is the largest contributor to the uncertainty in the calculation of the p-p, 13N, and 15O neutrino fluxes. However, for all neutrino fluxes, several elements contribute comparable amounts to the total composition uncertainty.

John N. Bahcall; Aldo M. Serenelli

2004-12-03T23:59:59.000Z

146

Studying neutrino oscillations using quasi-elastic events in MINOS  

SciTech Connect

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 {nu}{sub {mu}} {yields} {nu}{sub {tau}} oscillations and make a measurement on the oscillation parameters, {Delta}m{sub 23}{sup 2} and sin{sup 2} 2{theta}{sub 23}, via a {nu}{sub {mu}} 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 {mu} 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 {Delta}m{sub 23}{sup 2} and sin{sup 2} 2{theta}{sub 23} 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 {Delta}m{sub 23}{sup 2} = 2.91{sub -0.53}{sup +0.49}(stat){sub -0.09}{sup +0.08}(sys) x 10{sup -3} eV{sup 2} and sin{sup 2} 2{theta}{sub 23} = 0.990{sub -0.180}(stat){sub -0.030}(sys).

Kumaratunga, Sujeewa Terasita; /Minnesota U.

2008-02-01T23:59:59.000Z

147

Determining the neutrino mass hierarchy  

Science Conference Proceedings (OSTI)

In this proceedings I review the physics that future experiments will use to determine the neutrino mass hierarchy.

Parke, Stephen J.; /Fermilab

2006-07-01T23:59:59.000Z

148

Neutrinos: Windows to New Physics  

E-Print Network (OSTI)

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

R. D. Peccei

2006-09-20T23:59:59.000Z

149

Solar Neutrino Matter Effects Redux  

E-Print Network (OSTI)

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

A. B. Balantekin; A. Malkus

2011-09-24T23:59:59.000Z

150

Radiative inverse seesaw neutrino mass and dark matter  

SciTech Connect

Seesaw mechanism provides a natural explanation of light neutrino masses through suppression of heavy seesaw scale. In inverse seesaw models the seesaw scale can be much lower than that in the usual seesaw models. If terms inducing seesaw masses are further induced by loop corrections, the seesaw scale can be lowered to be in the range probed by experiments at the LHC without fine tuning. This talk, presented by X-G He, discuss models constructed in a recent preprint by us (arxiv:201207.6308) in which neutrino masses are generated at two loop level through inverse seesaw mechanism. These models also naturally have dark matter candidates. Although the recent data from Xenon100 put stringent constraint on the models, they can be consistent with data on neutrino masses, mixing, dark matter relic density and direct detection.

Guo Gang [INPAC, Department of Physics and Shanghai Key Laboratory for Particle Physics and Cosmology Shanghai Jiao Tong University, Shanghai (China); He Xiaogang [INPAC, Department of Physics and Shanghai Key Laboratory for Particle Physics and Cosmology Shanghai Jiao Tong University, Shanghai (China) and Department of Physics, National Tsing Hua University, and NCTS, Hsinchu, Taiwan (China); Li Guannan [INPAC, Department of Physics and Shanghai Key Laboratory for Particle Physics and Cosmology Shanghai Jiao Tong University, Shanghai, Taiwan (China)

2013-05-23T23:59:59.000Z

151

Light Sterile Neutrino from extra dimensions and Four-Neutrino Solutions to Neutrino Anomalies  

E-Print Network (OSTI)

We propose a four-neutrino model which can reconcile the existing data coming from underground experiments in terms of neutrino oscillations, together with the hint from the LSND experiment and a possible neutrino contribution to the hot dark matter of the Universe. It applies the idea that extra compact dimensions, probed only by gravity and possibly gauge-singlet fields, can lower the fundamental scales such as the Planck, string or unification scales. Our fourth light neutrino $\

A. Ioannisian; J. W. F. Valle

1999-11-14T23:59:59.000Z

152

First Measurement of the Branching Fraction of the Decay $\\psi(2S) \\to \\tau\\tau$  

E-Print Network (OSTI)

The branching fraction of the psi(2S) decay into tau pair has been measured for the first time using the BES detector at the Beijing Electron-Positron Collider. The result is $B_{\\tau\\tau}=(2.71\\pm 0.43 \\pm 0.55) \\times 10^{-3}$, where the first error is statistical and the second is systematic. This value, along with those for the branching fractions into e+e- and mu+mu of this resonance, satisfy well the relation predicted by the sequential lepton hypothesis. Combining all these values with the leptonic width of the resonance the total width of the psi(2S) is determined to be $(252 \\pm 37)$ keV.

Bai, J Z; Bian, J G; Blum, I K; Chen, G P; Chen, H F; Chen, J; Chen Jia Chao; Chen, Y; Chen, Y B; Chen, Y Q; Cheng Bao Sen; Cui, X Z; Ding, H L; Dong, L Y; Du, Z Z; Dunwoodie, W M; Gao, C S; Gao, M L; Gao, S Q; Gratton, P; Gu, J H; Gu, S D; Gu, W X; Gu, Y F; Guo, Z J; Guo, Y N; Han, S W; Han, Y; Harris, F A; He, J; He, J T; He, K L; He, M; Heng, Y K; Hitlin, D G; Hu, G Y; Hu, H M; Hu, J L; Hu, Q H; Hu, T; Hu Xiao Qing; Huang, G S; Huang, Y Z; Izen, J M; Jiang, C H; Jin, Y; Jones, B D; Ju, X; Ke, Z J; Kelsey, M H; Kim, B K; Kong, D; Lai, Y F; Lang, P F; Lankford, A J; Li, C G; Li, D; Li, H B; Li, J; Li, J C; Li, P Q; Li, R B; Li, W; Li, W G; Li, X H; Li Xiao Nan; Liu, H M; Liu, J; Liu, R G; Liu, Y; Lou, X C; Lowery, B; Lu, F; Lu, J G; Luo, X L; Ma, E C; Ma, J M; Malchow, R; Mao, H S; Mao, Z P; Meng, X C; Nie, J; Olsen, S L; Oyang, J Y T; Paluselli, D; Pan, L J; Panetta, J; Porter, F; Qi, N D; Qi, X R; Qian, C D; Qiu, J F; Qu, Y H; Que, Y K; Rong, G; Schernau, M; Shao, Y Y; Shen, B W; Shen, D L; Shen, H; Shen, X Y; Sheng, H Y; Shi, H Z; Song, X F; Standifird, J; Sun, F; Sun, H S; Sun, Y; Sun, Y Z; Tang, S Q; Toki, W; Tong, G L; Varner, G S; Wang, F; Wang, L S; Wang, L Z; Wang, M; Wang, P; Wang, P L; Wang, S M; Wang, T J; Wang, Y Y; Weaver, M; Wei, C L; Wu, J M; Wu, N; Wu, Y G; Xi, D M; Xia, X M; Xie, P P; Xie, Y; Xie, Y H; Xu, G F; Xue, S T; Yan, J; Yan, W G; Yang, C M; Yang, C Y; Yang, H X; Yang, J; Yang, W; Yang, X F; Ye, M H; Ye Shu Wei; Ye, Y X; Yu, C S; Yu, C X; Yu, G W; Yu Yu Hei; Yu, Z Q; Yuan, C Z; Yuan, Y; Zhang Bing Yun; Zhang, C; Zhang, C C; Zhang, D H; Zhang, H L; Zhang, J; Zhang, J W; Zhang, L; Zhang, L S; Zhang, P; Zhang, Q J; Zhang, S Q; Zhang, X Y; Zhang, Y Y; Zhao, D X; Zhao, H W; Zhao Jia Wei; Zhao, M; Zhao Wei Ren; Zhao, Z G; Zheng Jian Ping; Zheng Lin Sheng; Zheng Zhi Peng; Zhou, B Q; Zhou, G P; Zhou, H S; Zhou, L; Zhu, K J; Zhu, Q M; Zhu, Y C; Zhu, Y S; Zhuang, B A

2002-01-01T23:59:59.000Z

153

The CDF-II tau physics program triggers, tau ID and preliminary results  

SciTech Connect

The study of processes containing {tau} leptons in the final state will play an important role at Tevatron Run II. Such final states will be relevant both for electroweak studies and measurements as well as in searches for physics beyond the Standard Model. The present paper discusses the physics opportunities and challenges related to the implementation of new set of triggers able to select events containing tau candidates in the final state. They illustrate, in particular, the physics capabilities for a variety of new physics scenarios such as supersymmetry (SUSY), SUSY with Rp-parity violation, with Bilinear parity violation or models with the violation of lepton flavor. Finally, they present the first Run II results obtained using some of the described tau triggers.

C. Pagliarone et al.

2003-11-03T23:59:59.000Z

154

Entanglement in neutrino oscillations  

E-Print Network (OSTI)

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

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

2007-07-30T23:59:59.000Z

155

Cosmic coincidences and relic neutrinos  

E-Print Network (OSTI)

A simple phenomenological description for the energy transfer between a variable cosmological constant (CC) and a gas of relic neutrinos in an expanding universe can account for a near coincidence between the neutrino and dark-energy densities to hold over a significant portion of the history of the universe. Although such a cosmological setup may promote neutrinos to mass-varying particles, both with slow and quick neutrino mass changing with the expansion of the universe naturally implemented in the model, it also works equally well for static neutrino masses. We also stress what sort of models for variable CC can potentially underpin the above scenario.

R. Horvat

2006-12-04T23:59:59.000Z

156

Neutrino oscillations in an SO(10) supersymmetric grand unified theory with U(2)xU(1){sup n} family symmetry  

Science Conference Proceedings (OSTI)

In a previous paper we analyzed fermion masses (focusing on neutrino masses and mixing angles) in an SO(10) SUSY GUT with U(2)xU(1){sup n} family symmetry. The model is ''natural'' containing all operators in the Lagrangian consistent with the states and their charges. With minimal family symmetry breaking vacuum expectation values (VEVs) the model is also predictive giving a unique solution to atmospheric (with maximal {nu}{sub {mu}}{yields}{nu}{sub {tau}} mixing) and solar (with SMA MSW {nu}{sub e}{yields}{nu}{sub s} mixing) neutrino oscillations. In this paper we analyze the case of general family breaking VEVs. We now find several new solutions for three, four, and five neutrinos. For three neutrinos we now obtain SMA MSW, LMA MSW, or vacuum oscillation solutions for solar neutrinos. In all three cases the atmospheric data are described by maximal {nu}{sub {mu}}{yields}{nu}{sub {tau}} mixing. In the four and five neutrino cases, in addition to fitting atmospheric and solar data as before, we are now able to fit LSND data. All this is obtained with the additional parameters coming from the family symmetry breaking VEVs, providing only minor changes in the charged fermion fits. (c) 2000 The American Physical Society.

Blazek, T. [Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208 (United States); Raby, S. [Department of Physics, The Ohio State University, 174 W. 18th Ave., Columbus, Ohio 43210 (United States); Tobe, K. [Department of Physics, The Ohio State University, 174 W. 18th Ave., Columbus, Ohio 43210 (United States)

2000-09-01T23:59:59.000Z

157

Frederick Reines and the Neutrino  

Office of Scientific and Technical Information (OSTI)

Frederick Reines and the Detection of the Neutrino Frederick Reines and the Detection of the Neutrino Resources with Additional Information '[Frederick] Reines - known among scientists as the "father of neutrino physics" - won the Nobel Prize for physics in 1995 ["for the detection of the neutrino"], nearly 40 years after his neutrino experiments changed the world of physics and set in motion a new way of looking at the universe. ... Frederick Reines Courtesy University of California Irvine Until Reines's discovery, physicists had only theorized the existence of the neutrino - and physicists believed the tiny particles would never be detected. Reines's research laid the groundwork for new avenues of physics inquiry and hundreds of physics experiments that have tested central theories about the structure of our cosmos. The neutrino is one of the tiny spinning particles that are the building blocks of nature. ...

158

New Results on Solar Neutrinos  

E-Print Network (OSTI)

This paper reviews the constraints on the solar neutrino mixing parameters with data collected by the Homestake, SAGE, GALLEX, Kamiokande, SuperKamiokande, Borexino and SNO experiments. An emphasis will be given to the global solar neutrino analyses in terms of matter-enhanced oscillation of two and three active flavors. The results to-date, including both solar model dependent and independent measurements, indicate that electron neutrinos are changing to other active types on route to the Earth from the Sun. The total flux of solar neutrinos is found to be in very good agreement with solar model calculations. Today, solar neutrino measurements focus on greater accuracy for mixing parameters and on better sensitivity to low neutrino energies. This article also summarizes near future prospects in the field of solar neutrino physics.

Alain Bellerive

2010-12-11T23:59:59.000Z

159

New Results on Solar Neutrinos  

E-Print Network (OSTI)

This paper reviews the constraints on the solar neutrino mixing parameters with data collected by the Homestake, SAGE, GALLEX, Kamiokande, SuperKamiokande, Borexino and SNO experiments. An emphasis will be given to the global solar neutrino analyses in terms of matter-enhanced oscillation of two and three active flavors. The results to-date, including both solar model dependent and independent measurements, indicate that electron neutrinos are changing to other active types on route to the Earth from the Sun. The total flux of solar neutrinos is found to be in very good agreement with solar model calculations. Today, solar neutrino measurements focus on greater accuracy for mixing parameters and on better sensitivity to low neutrino energies. This article also summarizes near future prospects in the field of solar neutrino physics.

Bellerive, Alain

2010-01-01T23:59:59.000Z

160

A Search for Neutrinoless Tau Decays to Three Leptons  

SciTech Connect

Using approximately 350 million {tau}{sup +}{tau}{sup -} pair events recorded with the BaBar detector at the Stanford Linear Accelerator Center between 1999 and 2006, a search has been made for neutrinoless, lepton-flavor violating tau decays to three lighter leptons. All six decay modes consistent with conservation of electric charge and energy have been considered. With signal selection efficiencies of 5-12%, we obtain 90% confidence level upper limits on the branching fraction {Beta}({tau} {yields} {ell}{ell}{ell}) in the range (4-8) x 10{sup -8}.

Kolb, Jeffrey A.; /Oregon U. /SLAC

2008-09-24T23:59:59.000Z

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161

Signals, backgrounds and calibrations in the Sudbury Neutrino Observatory  

Science Conference Proceedings (OSTI)

The Sudbury Neutrino Observatory is a large underground neutrino detector which is presently under construction

Bhaskar Sur; The SNO Collaboration

1995-01-01T23:59:59.000Z

162

New Neutrinos Algal Biofuels  

E-Print Network (OSTI)

New Neutrinos Algal Biofuels Charged-Particle Vision Primordial Soup LOS ALAMOS SCIENCE biofuels to run our cars, but if it costs $10 per gallon and requires petroleum products for production seven billion people, the nation seeks a competitive alternative to crude oil. Biofuel is a popular

163

Deviations from Tri-Bimaximal Neutrino Mixing Using Type II Seesaw  

E-Print Network (OSTI)

We study the possibility of generating deviations from tri-bimaximal (TBM) neutrino mixing to explain the non-zero reactor mixing angle within the framework of both type I and type II seesaw mechanisms. The type I seesaw term gives rise to the $\\mu-\\tau$ symmetric TBM pattern of neutrino mass matrix as predicted by generic flavor symmetry models like $A_4$ whereas the type II seesaw term gives rise to the required deviations from TBM pattern to explain the non-zero $\\theta_{13}$. Considering extremal values of Majorana CP phases such that the neutrino mass eigenvalues have the structure $(m_1, -m_2, m_3)$ and $(m_1, m_2, m_3)$, we numerically fit the type I seesaw term by taking oscillation as well as cosmology data and then compute the predictions for neutrino parameters after the type II seesaw term is introduced. We consider a minimal structure of the type II seesaw term and check whether the predictions for neutrino parameters lie in the $3\\sigma$ range. We also outline two possible flavor symmetry models to justify the minimal structure of the type II seesaw term considered in the analysis.

Debasish Borah

2013-07-09T23:59:59.000Z

164

Raymond Davis Jr., Solar Neutrinos, and the Solar Neutrino Problems  

Office of Scientific and Technical Information (OSTI)

Raymond Davis, Jr., Solar Neutrinos, Raymond Davis, Jr., Solar Neutrinos, and the Solar Neutrino Problem Resources with Additional Information Raymond Davis, Jr. Photo Courtesy of Brookhaven National Laboratory (BNL) Raymond Davis, Jr., who conducted research in the Chemistry Department at Brookhaven National Laboratory (BNL) from 1948 through 1984, was awarded the 2002 Nobel Prize in Physics "for pioneering contributions to astrophysics, in particular for the detection of cosmic neutrinos." Dr. Davis is also a recipient of the 2003 Fermi Award. He was the first scientist to detect solar neutrinos, ghostlike particles produced in the nuclear reactions that power the sun. "Neutrinos are fascinating particles, so tiny and fast that they can pass straight through everything, even the earth itself, without even slowing down," said Davis. "When I began my work, I was intrigued by the idea of learning something new. The interesting thing about doing new experiments is that you never know what the answer is going to be!"

165

Precision Solar Neutrino Measurements with the Sudbury Neutrino Observatory  

Science Conference Proceedings (OSTI)

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

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

2007-10-26T23:59:59.000Z

166

Minimal Neutrino Texture with Neutrino Mass Ratio and Cabibbo Angle  

E-Print Network (OSTI)

We present neutrino mass matrix textures in a minimal framework of the type-I seesaw mechanism where two right-handed Majorana neutrinos are introduced in order to reproduce experimental results of neutrino oscillations. The textures can lead to experimentally favored leptonic mixing angles described by the tri-bimaximal mixing with one additional rotation. We present minimal and next to minimal textures for the normal mass hierarchy case in a context of the texture zero. A minimal texture in the inverted hierarchy case is also constructed, which does not have any vanishing entries in a Dirac neutrino mass matrix. We also discuss some cases that model parameters in the textures are supposed to be a neutrino mass ratio and/or the Cabibbo angle. Predicted regions of mixing angles, a leptonic CP-violation parameter, and an effective mass for the neutrino-less double beta decay are presented in all textures.

Yusuke Shimizu; Ryo Takahashi; Morimitsu Tanimoto

2012-12-24T23:59:59.000Z

167

On the Detection of the Free Neutrino  

DOE R&D Accomplishments (OSTI)

The experiment previously proposed [to Detect the Free Neutrino] has been initiated, with a Hanford pile as a neutrino source. It appears probable that neutrino detection has been accomplished, and confirmatory work is in progress. (K.S.)

Reines, F.; Cowan, C. L., Jr.

1953-08-06T23:59:59.000Z

168

Octahedral Symmetry with Geometrical Breaking: New Prediction for Neutrino Mixing Angle theta_{13} and CP Violation  

E-Print Network (OSTI)

We propose octahedral group O_h as the family symmetry of neutrino-lepton sector, with subgroups Z_2(mu-tau) x Z_2(solar) and Z_4^l as the residual symmetries of neutrinos and charged leptons, respectively. We find that O_h is a minimal group which contains the subgroups Z_2(mu-tau) x Z_2(solar) and Z_4^l for realizing the bimaximal mixings theta_{23} = theta_{12} = 45^o. We present geometric interpretations of O_h and its residual symmetries, and further construct a natural geometrical breaking of Z_4^l. Our theory makes truly simple new predictions of a relatively large reactor angle, theta_{13} = 45^o - theta_{12} = 7.9^o - 14.0^o (3 sigma), the maximal atmospheric angle theta_{23} = 45^o, and the maximal Dirac CP violation delta_D = +-90^o. These agree well with the current neutrino data, and will be further probed by the on-going and upcoming oscillation experiments.

He, Hong-Jian

2012-01-01T23:59:59.000Z

169

Octahedral Symmetry with Geometrical Breaking: New Prediction for Neutrino Mixing Angle theta_{13} and CP Violation  

E-Print Network (OSTI)

We propose octahedral group O_h as the family symmetry of neutrino-lepton sector. We find that O_h contains subgroups Z_2(mu-tau) x Z_2(solar) and Z_4^l for realizing the bimaximal (BM) mixings, theta_{23} = theta_{12} = 45^o and theta_{13}=0^o, where Z_2(mu-tau) x Z_2(solar) and Z_4^l serve as the residual symmetries of neutrinos and charged leptons, respectively. We present geometric interpretations of BM mixing in the octahedron, and construct natural geometrical breaking of Z_4^l, leading to nontrivial deviations from the BM mixings. Our theory makes truly simple predictions of a relatively large reactor angle, theta_{13} = 45^o - theta_{12} = 7.5^o - 13.7^o (3 sigma), the nearly maximal atmospheric angle and the approximate maximal Dirac CP violation. These agree well with the current neutrino data, and will be further probed by the on-going and upcoming oscillation experiments.

Hong-Jian He; Xun-Jie Xu

2012-03-13T23:59:59.000Z

170

Solar neutrino experiments: An update  

Science Conference Proceedings (OSTI)

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

Hahn, R.L.

1993-12-31T23:59:59.000Z

171

Low-energy solar anti-neutrinos  

E-Print Network (OSTI)

If neutrino conversions within the Sun result in partial polarization of initial solar neutrino fluxes, then a new opportunity arises to observe the anti-\

V. B. Semikoz; S. Pastor; J. W. F. Valle

1998-08-13T23:59:59.000Z

172

Light Sterile Neutrinos: A White Paper  

E-Print Network (OSTI)

This white paper addresses the hypothesis of light sterile neutrinos based on recent anomalies observed in neutrino experiments and the latest astrophysical data.

K. N. Abazajian; M. A. Acero; S. K. Agarwalla; A. A. Aguilar-Arevalo; C. H. Albright; S. Antusch; C. A. Arguelles; A. B. Balantekin; G. Barenboim; V. Barger; P. Bernardini; F. Bezrukov; O. E. Bjaelde; S. A. Bogacz; N. S. Bowden; A. Boyarsky; A. Bravar; D. Bravo Berguno; S. J. Brice; A. D. Bross; B. Caccianiga; F. Cavanna; E. J. Chun; B. T. Cleveland; A. P. Collin; P. Coloma; J. M. Conrad; M. Cribier; A. S. Cucoanes; J. C. D'Olivo; S. Das; A. de Gouvea; A. V. Derbin; R. Dharmapalan; J. S. Diaz; X. J. Ding; Z. Djurcic; A. Donini; D. Duchesneau; H. Ejiri; S. R. Elliott; D. J. Ernst; A. Esmaili; J. J. Evans; E. Fernandez-Martinez; E. Figueroa-Feliciano; B. T. Fleming; J. A. Formaggio; D. Franco; J. Gaffiot; R. Gandhi; Y. Gao; G. T. Garvey; V. N. Gavrin; P. Ghoshal; D. Gibin; C. Giunti; S. N. Gninenko; V. V. Gorbachev; D. S. Gorbunov; R. Guenette; A. Guglielmi; F. Halzen; J. Hamann; S. Hannestad; W. Haxton; K. M. Heeger; R. Henning; P. Hernandez; P. Huber; W. Huelsnitz; A. Ianni; T. V. Ibragimova; Y. Karadzhov; G. Karagiorgi; G. Keefer; Y. D. Kim; J. Kopp; V. N. Kornoukhov; A. Kusenko; P. Kyberd; P. Langacker; Th. Lasserre; M. Laveder; A. Letourneau; D. Lhuillier; Y. F. Li; M. Lindner; J. M. Link; B. L. Littlejohn; P. Lombardi; K. Long; J. Lopez-Pavon; W. C. Louis; L. Ludhova; J. D. Lykken; P. A. N. Machado; M. Maltoni; W. A. Mann; D. Marfatia; C. Mariani; V. A. Matveev; N. E. Mavromatos; A. Melchiorri; D. Meloni; O. Mena; G. Mention; A. Merle; E. Meroni; M. Mezzetto; G. B. Mills; D. Minic; L. Miramonti; D. Mohapatra; R. N. Mohapatra; C. Montanari; Y. Mori; Th. A. Mueller; H. P. Mumm; V. Muratova; A. E. Nelson; J. S. Nico; E. Noah; J. Nowak; O. Yu. Smirnov; M. Obolensky; S. Pakvasa; O. Palamara; M. Pallavicini; S. Pascoli; L. Patrizii; Z. Pavlovic; O. L. G. Peres; H. Pessard; F. Pietropaolo; M. L. Pitt; M. Popovic; J. Pradler; G. Ranucci; H. Ray; S. Razzaque; B. Rebel; R. G. H. Robertson; W. Rodejohann; S. D. Rountree; C. Rubbia; O. Ruchayskiy; P. R. Sala; K. Scholberg; T. Schwetz; M. H. Shaevitz; M. Shaposhnikov; R. Shrock; S. Simone; M. Skorokhvatov; M. Sorel; A. Sousa; D. N. Spergel; J. Spitz; L. Stanco; I. Stancu; A. Suzuki; T. Takeuchi; I. Tamborra; J. Tang; G. Testera; X. C. Tian; A. Tonazzo; C. D. Tunnell; R. G. Van de Water; L. Verde; E. P. Veretenkin; C. Vignoli; M. Vivier; R. B. Vogelaar; M. O. Wascko; J. F. Wilkerson; W. Winter; Y. Y. Y. Wong; T. T. Yanagida; O. Yasuda; M. Yeh; F. Yermia; Z. W. Yokley; G. P. Zeller; L. Zhan; H. Zhang

2012-04-18T23:59:59.000Z

173

Commissioning of the calorimetry in the ATLAS tau trigger system  

E-Print Network (OSTI)

Calorimeters are fundamental in the three levels of the ATLAS tau trigger system. The first level trigger (L1) uses the electromagnetic (e.m.) and hadronic (had) calorimeters to make its decision. In the High Level Triggers (HLT), these systems are also crucial: both the second level trigger (L2) and the third level trigger (Event Filter -EF) heavily exploit the calorimeter based information to identify tau leptons decaying hadronically. Whilst the granularity of the first level is coarse, the second and third level triggers have the final full detector read-out. This contribution focuses on the commissioning of the calorimetry in the three levels of the tau trigger in real data. Efficiency measurements with respect to tau candidates reconstructed by the offline algorithms, and distributions of calorimeter based tau information reconstructed at trigger level, are compared to prediction of the Monte Carlo and the trigger performance in first data assessed.

Sfyrla, Anna; The ATLAS collaboration

2010-01-01T23:59:59.000Z

174

Commissioning of the calorimetry in the ATLAS tau trigger system  

E-Print Network (OSTI)

Calorimeters are fundamental in the three levels of the ATLAS tau trigger system. The first level trigger (L1) uses the electromagnetic (EM) and hadronic (HAD) calorimeters to make its decision. In the High Level Triggers (HLT), these systems are also crucial: both the second level trigger (L2) and the third level trigger (Event Filter -EF) heavily exploit the calorimeter based information to identify tau leptons decaying hadronically. Whilst the granularity of the first level is coarse, the second and third level triggers have the final full detector read-out. This contribution focuses on the commissioning of the calorimetry in the three levels of the tau trigger in real data. Efficiency measurements with respect to tau candidates reconstructed by the offline algorithms, and distributions of calorimeter based tau information reconstructed at trigger level, are compared to prediction of the Monte Carlo and the trigger performance in first data assessed.

Sfyrla, Anna; The ATLAS collaboration

2010-01-01T23:59:59.000Z

175

Neutrino Opacities in Nuclear Matter  

E-Print Network (OSTI)

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

Adam Burrows; Sanjay Reddy; Todd A. Thompson

2004-04-21T23:59:59.000Z

176

Limits on Neutrino-Neutrino Scattering in the Early Universe  

E-Print Network (OSTI)

In the standard model neutrinos are assumed to have streamed across the Universe since they last scattered at the weak decoupling epoch when the temperature of the standard-model plasma was ~MeV. The shear stress of free-streaming neutrinos imprints itself gravitationally on the Cosmic Microwave Background (CMB) and makes the CMB a sensitive probe of neutrino scattering. Yet, the presence of nonstandard physics in the neutrino sector may alter this standard chronology and delay neutrino free-streaming until a much later epoch. We use observations of the CMB to constrain the strength of neutrino self-interactions G_eff and put limits on new physics in the neutrino sector from the early Universe. Recent measurements of the CMB at large multipoles made by the Planck satellite and high-l experiments are critical for probing this physics. Within the context of conventional LambdaCDM parameters cosmological data are compatible with G_eff cooled to as low as ~25 eV. Intriguingly, we also find an alternative cosmology compatible with cosmological data in which neutrinos scatter off each other until z~10^4 with a preferred interaction strength in a narrow region around G_eff = 1/(10 MeV)^2. This distinct self-interacting neutrino cosmology is characterized by somewhat lower values of both the scalar spectral index and the amplitude of primordial fluctuations. While we phrase our discussion here in terms of a specific scenario in which a late onset of neutrino free-streaming could occur, our constraints on the neutrino visibility function are very general.

Francis-Yan Cyr-Racine; Kris Sigurdson

2013-06-06T23:59:59.000Z

177

Neutrino Factory Feasibility Study  

NLE Websites -- All DOE Office Websites (Extended Search)

6-1 - 6-1 - April 15 th , 2000 6. Cooling 6.1 Introduction The goal of this six-month study is an integrated design for a neutrino source, subject to realistic engineering constraints. As will become evident, the coupling between the cooling-channel design and the design of the upstream components is critical to achieving the best performance. Nevertheless, to make sufficiently rapid progress it has been necessary to design the various components semi-independently, then optimize and iterate to converge towards an integrated design. While we have not yet arrived at a fully optimized design, we have studied sufficiently the cooling channels described below to determine that their performance is limited primarily by the performance of the current phase-rotation and buncher designs. While the designs presented here suffice for an entry-level neutrino factory (10

178

Predictions for the Cosmogenic Neutrino Flux in Light of New Data from the Pierre Auger Observatory  

E-Print Network (OSTI)

The Pierre Auger Observatory (PAO) has measured the spectrum and composition of the ultrahigh energy cosmic rays with unprecedented precision. We use these measurements to constrain their spectrum and composition as injected from their sources and, in turn, use these results to estimate the spectrum of cosmogenic neutrinos generated in their propagation through intergalactic space. We find that the PAO measurements can be well fit if the injected cosmic rays consist entirely of nuclei with masses in the intermediate (C, N, O) to heavy (Fe, Si) range. A mixture of protons and heavier species is also acceptable but (on the basis of existing hadronic interaction models) injection of pure light nuclei (p, He) results in unacceptable fits to the new elongation rate data. The expected spectrum of cosmogenic neutrinos can vary considerably, depending on the precise spectrum and chemical composition injected from the cosmic ray sources. In the models where heavy nuclei dominate the cosmic ray spectrum and few dissociated protons exceed GZK energies, the cosmogenic neutrino flux can be suppressed by up to two orders of magnitude relative to the all-proton prediction, making its detection beyond the reach of current and planned neutrino telescopes. Other models consistent with the data, however, are proton-dominated with only a small (1-10%) admixture of heavy nuclei and predict an associated cosmogenic flux within the reach of upcoming experiments. Thus a detection or non-detection of cosmogenic neutrinos can assist in discriminating between these possibilities.

Luis A. Anchordoqui; Haim Goldberg; Dan Hooper; Subir Sarkar; Andrew M. Taylor

2007-09-05T23:59:59.000Z

179

Higgs boson coupling sensitivity at the LHC using H->tau tau decays  

E-Print Network (OSTI)

We investigate the potential for measuring the relative couplings of a low-mass Higgs boson at the Large Hadron Collider using WH, ZH, and ttbarH production, where the Higgs boson decays to tau-lepton pairs. With 100/fb of sqrt(s) = 14 TeV pp collision data we find that these modes can improve sensitivity to coupling-ratio measurements of a Higgs boson with a mass of about 125 GeV/c^2.

Boddy, Christopher; Hays, Christopher

2012-01-01T23:59:59.000Z

180

Tuning and Analysis Utilities (TAU) on BG/P Systems | Argonne Leadership  

NLE Websites -- All DOE Office Websites (Extended Search)

and Analysis Utilities (TAU) on BG/P Systems and Analysis Utilities (TAU) on BG/P Systems References TAU Project Site TAU Instrumentation Methods TAU Compilation Options TAU Fortran Instrumentation FAQ TAU Leap to Petascale 2009 Presentation TAU Workshop 2009 Introduction The TAU (Tuning and Analysis Utilities) Performance System is a portable profiling and tracing toolkit for performance analysis of parallel programs written in Fortran, C, C++, Java, Python. TAU gathers performance information while a program executes through instrumentation of functions, methods, basic blocks, and statements. The instrumentation consists of calls to TAU library routines which can be incorporated into a program in several ways: automatic instrumentation of the code at the source level using the Program Database Toolkit (PDT)

Note: This page contains sample records for the topic "tau neutrinos heavy" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Measurement of the tau- to eta pi-pi+pi-nu tau Branching Fraction and a Search for a Second-Class Current in the tau- to eta'(958)pi-nu tau Decay  

SciTech Connect

The {tau}{sup -} {yields} {eta}{pi}{sup -}{pi}{sup +}{pi}{sup -}{nu}{sub {tau}} decay with the {eta} {yields} {gamma}{gamma} mode is studied using 384 fb{sup -1} of data collected by the BABAR detector. The branching fraction is measured to be (1.60 {+-} 0.05 {+-} 0.11) x 10{sup -4}. It is found that {tau}{sup -} {yields} f{sub 1}(1285){pi}{sup -} {nu}{sub {tau}} {yields} {eta}{pi}{sup -}{pi}{sup +}{pi}{sup -}{nu}{sub {tau}} is the dominant decay mode with a branching fraction of (1.11 {+-} 0.06 {+-} 0.05) x 10{sup -4}. The first error on the branching fractions is statistical and the second systematic. In addition, a 90% confidence level upper limit on the branching fraction of the {tau}{sup -} {yields} {eta}{prime}(958){pi}{sup -}{nu}{sub {tau}} decay is measured to be 7.2 x 10{sup -6}. This last decay proceeds through a second-class current and is expected to be forbidden in the limit of isospin symmetry.

Aubert, B.; Bona, M.; Boutigny, D.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prudent, X.; Tisserand, V.; Zghiche, A.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Lopez, L.; Palano, A.; Pappagallo, M.; /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Abrams, G.S.; Battaglia, M.; Brown, David Nathan; Button-Shafer, J.; /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /Frascati /Genoa U. /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Karlsruhe U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /Paris U., VI-VII /Pennsylvania U. /Perugia U. /Pisa U. /Princeton U. /INFN, Rome /Rostock U. /Rutherford /DSM, DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison /Yale U.

2008-03-24T23:59:59.000Z

182

Historic Sudbury Neutrino Observatory Data, Carried by ESnet, Lives on at  

NLE Websites -- All DOE Office Websites (Extended Search)

Historic Sudbury Historic Sudbury Neutrino Observatory Data, Carried by ESnet, Lives on at NERSC Historic Sudbury Neutrino Observatory Data, Carried by ESnet, Lives on at NERSC January 26, 2010 | Tags: Astrophysics Contact: Linda Vu, lvu@lbl.gov, +1 510 486 2402 SNO.jpg SNO onsists of an 18-meters-in-diameter stainless steel geodesic sphere inside of which is an acrylic vessel filled with 1000 tons of heavy water (deuterium oxide or D2O). Attached to the sphere are 9,522 ultra-sensitive light-sensors called photomultiplier tubes. When neutrinos passing through the heavy water interact with deuterium nuclei, flashes of light are emitted. The photomultiplier tubes detect these light flashes and convert them into electronic signals that scientists can analyze for the presence

183

Geomagnetic Effects on Atmospheric Neutrinos  

E-Print Network (OSTI)

Geomagnetic effects distort the zenith angle distribution of sub--GeV and few--GeV atmospheric neutrinos, breaking the up--down symmetry that would be present in the absence of neutrino oscillations and without a geomagnetic field. The geomagnetic effects also produce a characteristic azimuthal dependence of the $\

Paolo Lipari; T. K. Gaisser; Todor Stanev

1998-03-09T23:59:59.000Z

184

Solar Hydrogen Burning and Neutrinos  

E-Print Network (OSTI)

We summarize the current status of laboratory measurements of nuclear cross sections of the pp chain and CN cycle. We discuss the connections between such measurements, predictions of solar neutrino fluxes, and the conclusion that solar neutrinos oscillate before reaching earth.

W. C. Haxton; P. D. Parker; C. E. Rolfs

2005-01-10T23:59:59.000Z

185

Off-shell OPERA neutrinos  

E-Print Network (OSTI)

In the OPERA experiment, superluminal propagation of neutrinos can occur if one of the neutrino masses is extremely small. However the effect only has appreciable amplitude at energies of order this mass and thus has negligible overlap with the multi-GeV scale of the experiment.

Tim R. Morris

2011-10-14T23:59:59.000Z

186

Observation of Geo-Neutrinos  

E-Print Network (OSTI)

Geo-neutrinos, electron anti-neutrinos produced in beta decays of naturally occurring radioactive isotopes in the Earth, are a unique direct probe of our planet's interior. We report the first observation at more than 3$\\sigma$ C.L. of geo-neutrinos, performed with the Borexino detector at Laboratori Nazionali del Gran Sasso. Anti-neutrinos are detected through the neutron inverse beta decay reaction. With a 252.6 ton-yr fiducial exposure after all selection cuts, we detected 9.9^{+4.1}_{-3.4}(^{+14.6}_{-8.2}) geo-neutrino events, with errors corresponding to a 68.3%(99.73%) C.L. From the $\\ln{\\cal{L}}$ profile, the statistical significance of the Borexino geo-neutrino observation corresponds to a 99.997% C.L. Our measurement of the geo-neutrinos rate is 3.9^{+1.6}_{-1.3}(^{+5.8}_{-3.2}) events/(100ton-yr). This measurement rejects the hypothesis of an active geo-reactor in the Earth's core with a power above 3 TW at 95% C.L. The observed prompt positron spectrum above 2.6 MeV is compatible with that expected from european nuclear reactors (mean base line of approximately 1000 km). Our measurement of reactor anti-neutrinos excludes the non-oscillation hypothesis at 99.60% C.L.

Borexino Collaboration

2010-03-01T23:59:59.000Z

187

Review of Solar Neutrino Experiments  

E-Print Network (OSTI)

This paper reviews the constraints on the solar neutrino mixing parameters with data collected by the Homestake, SAGE, GALLEX, Kamiokande, SuperKamiokande, and SNO experiments. An emphasis will be given to the global solar neutrino analyses in terms of matter-enhanced oscillation of two active flavors. The results to-date, including both solar model dependent and independent measurements, indicate that electron neutrinos are changing to other active types on route to the Earth from the Sun. The total flux of solar neutrinos is found to be in very good agreement with solar model calculations. Future measurements will focus on greater accuracy for mixing parameters and on better sensitivity to low neutrino energies.

Alain Bellerive

2003-12-16T23:59:59.000Z

188

The Daya Bay Reactor Neutrino Experiment Sees Evidence that Electron...  

Office of Science (SC) Website

Neutrino Experiment Sees Evidence that Electron Neutrinos Turn into Muon Neutrinos Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP...

189

neutrino_mixing_s805.dvi  

NLE Websites -- All DOE Office Websites (Extended Search)

NEUTRINO NEUTRINO PHYSICS AS EXPLORED BY FLAVOR CHANGE Written May 2002 by B. Kayser (Fermilab). I. The physics of flavor change: The rather convincing evidence that atmospheric neutrinos change from one flavor to another has now been joined by new, very strong evidence that the solar neutrinos do this as well. Neutrino flavor change implies that neutrinos have nonzero masses. That is, there is a spectrum of three or more neutrino mass eigenstates, ν 1 , ν 2 , ν 3 , . . ., that are the analogues of the charged-lepton mass eigenstates, e, µ, and τ . Neutrino flavor change also implies leptonic mixing. That is, the weak interaction coupling the W boson to a charged lepton and a neutrino can couple any charged-lepton mass eigenstate α to any neutrino mass eigenstate ν i . Here, α = e, µ, or τ , and e is the electron, etc. Leptonic W + decay can yield a particular + α in association with any ν i . The amplitude

190

Search for CP Violation in the Decay tau- \\to pi- K^0_S (>= 0 pi0) nu_tau  

SciTech Connect

We report a search for CP violation in the decay {tau}{sup -} {yields} {pi}{sup -}K{sub S}{sup 0}({>=} 0{pi}{sup 0}){nu}{sub {tau}} using a dataset of 437 million {tau} lepton pairs, corresponding to an integrated luminosity of 476 fb{sup -1}, collected with the BABAR detector at the PEP-II asymmetric energy e{sup +}e{sup -} storage rings. The CP-violating decay-rate asymmetry is determined to be (-0.45 {+-} 0.24 {+-} 0.11)%, approximately three standard deviations from the Standard Model prediction of (0.33 {+-} 0.01)%.

Lees, J.P.; Poireau, V.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; /INFN, Bari /Bari U.; Milanes, D.A.; /INFN, Bari; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; /Bergen U.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; /UC, Berkeley; Koch, H.; Schroeder, T.; /Ruhr U., Bochum; Asgeirsson, D.J.; Hearty, C.; Mattison, T.S.; McKenna, J.A.; /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /Indian Inst. Tech., Guwahati /Harvard U. /Harvey Mudd Coll. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Paris U., VI-VII /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /Pisa U. /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas Nuclear Corp., Austin /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

2012-02-16T23:59:59.000Z

191

Almost Degenerate Neutrinos with Maximal Mixing  

E-Print Network (OSTI)

If the upper limit on the effective (Majorana) neutrino mass from neutrinoless double beta decay experiments is confirmed to be much less than an electron-volt, then one way to reconcile it with the degenerate neutrino mass pattern suggested recently to explain the observed deficit of solar and atmospheric neutrinos as well as neutrinos as HDM is to postulate that there be maximal mixing among the three light (or two) neutrinos. This suggestion is advanced in this paper and is analysed.

R. N. Mohapatra; S. Nussinov

1994-11-11T23:59:59.000Z

192

Study of High-multiplicity 3-prong and 5-prong Tau Decays at BaBar  

SciTech Connect

We present measurements of the branching fractions of 3-prong and 5-prong {tau} decay modes using a sample of 430 million {tau} lepton pairs, corresponding to an integrated luminosity of 468 fb{sup -1}, collected with the BABAR detector at the PEP-II asymmetric energy e{sup +}e{sup -} storage rings. The {tau}{sup -} {yields} (3{pi}){sup -} {eta}{nu}{sub {tau}}, {tau}{sup -} {yields} (3{pi}){sup -} {yields} {omega}{nu}{sub {tau}} and {tau}{sup -} {yields} {pi}{sup -} f{sub 1}(1285){nu}{sub {tau}} branching fractions are presented as well as a new limit on the branching fraction of the isospin-forbidden, second-class current {tau}{sup -} {yields} {pi}{sup -} {eta}{prime}(958){nu}{sub {tau}} decay. We find no evidence for charged kaons in these decay modes and place the first upper limits on their branching fractions.

Lees, J.P

2012-06-01T23:59:59.000Z

193

Measurement of \\mathcal{B}(\\tau^{-}\\-->\\bar{K^{0}}\\pi^{-}\  

SciTech Connect

A preliminary measurement of the branching fraction {Beta}({tau}{sup -} {yields} K{sub S}{sup 0}{pi}{sup -}{nu}{sub {tau}}) is made using 384.6 fb{sup -1} of e{sup +}e{sup -} collision data provided by the PEP-II collider, operating primarily at {radical}s = 10.58 GeV, and recorded using the BABAR detector. From this they measure: {Beta}({tau}{sup -} {yields} {bar K}{sup 0}{pi}{sup -}{nu}{sub {tau}}) = (0.840 {+-} 0.004(stat) {+-} 0.023(syst))%. This result is the most precise measurement to date and is consistent with the world average.

Wren, A

2008-08-13T23:59:59.000Z

194

Solar Neutrinos: Status and Prospects  

E-Print Network (OSTI)

We describe the current status of solar neutrino measurements and of the theory -- both neutrino physics and solar astrophysics -- employed in interpreting measurements. Important recent developments include Super-Kamiokande's determination of the neutrino-electron elastic scattering rate for 8B neutrinos to 3%; the latest SNO global analysis in which the inclusion of low-energy data from SNO I and II significantly narrowed the range of allowed values for the neutrino mixing angle theta12; Borexino results for both the 7Be and pep neutrino fluxes, the first direct measurements constraining the rate of ppI and ppII burning in the Sun; global reanalyses of solar neutrino data that take into account new reactor results on theta13; a new decadal evaluation of the nuclear physics of the pp chain and CNO cycle defining best values and uncertainties in the nuclear microphysics input to solar models; recognition of an emerging discrepancy between two tests of solar metallicity, helioseismological mappings of the soun...

Robertson, W C Haxton R G Hamish

2012-01-01T23:59:59.000Z

195

High-energy atmospheric neutrinos  

E-Print Network (OSTI)

High-energy neutrinos, arising from decays of mesons that were produced through the cosmic rays collisions with air nuclei, form unavoidable background noise in the astrophysical neutrino detection problem. The atmospheric neutrino flux above 1 PeV should be supposedly dominated by the contribution of charmed particle decays. These (prompt) neutrinos originated from decays of massive and shortlived particles, $D^\\pm$, $D^0$, $\\bar{D}{}^0$, $D_s^\\pm$, $\\Lambda^+_c$, form the most uncertain fraction of the high-energy atmospheric neutrino flux because of poor explored processes of the charm production. Besides, an ambiguity in high-energy behavior of pion and especially kaon production cross sections for nucleon-nucleus collisions may affect essentially the calculated neutrino flux. There is the energy region where above flux uncertainties superimpose. A new calculation presented here reveals sizable differences, up to the factor of 1.8 above 1 TeV, in muon neutrino flux predictions obtained with usage of known...

Sinegovsky, S I; Sinegovskaya, T S

2010-01-01T23:59:59.000Z

196

High-energy atmospheric neutrinos  

E-Print Network (OSTI)

High-energy neutrinos, arising from decays of mesons that were produced through the cosmic rays collisions with air nuclei, form unavoidable background noise in the astrophysical neutrino detection problem. The atmospheric neutrino flux above 1 PeV should be supposedly dominated by the contribution of charmed particle decays. These (prompt) neutrinos originated from decays of massive and shortlived particles, $D^\\pm$, $D^0$, $\\bar{D}{}^0$, $D_s^\\pm$, $\\Lambda^+_c$, form the most uncertain fraction of the high-energy atmospheric neutrino flux because of poor explored processes of the charm production. Besides, an ambiguity in high-energy behavior of pion and especially kaon production cross sections for nucleon-nucleus collisions may affect essentially the calculated neutrino flux. There is the energy region where above flux uncertainties superimpose. A new calculation presented here reveals sizable differences, up to the factor of 1.8 above 1 TeV, in muon neutrino flux predictions obtained with usage of known hadronic models, SIBYLL 2.1 and QGSJET-II. The atmospheric neutrino flux in the energy range $10-10^7$ GeV was computed within the 1D approach to solve nuclear cascade equations in the atmosphere, which takes into account non-scaling behavior of the inclusive cross-sections for the particle production, the rise of total inelastic hadron-nucleus cross-sections and nonpower-law character of the primary cosmic ray spectrum. This approach was recently tested in the atmospheric muon flux calculations [1]. The results of the neutrino flux calculations are compared with the Frejus, AMANDA-II and IceCube measurement data.

S. I. Sinegovsky; A. A. Kochanov; T. S. Sinegovskaya

2010-10-12T23:59:59.000Z

197

Neutrinos in Cosmology and Astrophysics  

E-Print Network (OSTI)

We briefly review the recent developments in neutrino physics and astrophysics which have import for frontline research in nuclear physics. These developments, we argue, tie nuclear physics to exciting developments in observational cosmology and astrophysics in new ways. Moreover, the behavior of neutrinos in dense matter is itself a fundamental problem in many-body quantum mechanics, in some ways akin to well-known issues in nuclear matter and nuclei, and in some ways radically different, especially because of nonlinearity and quantum de-coherence. The self-interacting neutrino gas is the only many body system driven by the weak interactions.

A. B. Balantekin; G. M. Fuller

2013-03-15T23:59:59.000Z

198

Evidence for neutrino oscillations in the Sudbury Neutrino Observatory  

E-Print Network (OSTI)

ux in the Standard Solar Model of the Sun. The long-standingwithin the solar core (inner ?20% of the Suns radius). Thesolar neutrino ?ux probe the nuclear fusion reactions fueling the Sun.

Marino, Alysia Diane

2004-01-01T23:59:59.000Z

199

The neutrino process and neutrino r-process  

SciTech Connect

Almost all of the 3 {center dot} 10{sup 53} ergs released in a core-collapse supernova is carried off by the neutrinos emitted from the cooling neutron star. These neutrinos can excite nuclei in the mantle of the star by their neutral and charged current reactions, leading to the spallation of nucleonsa and {alpha}-particles and the production of new daughter nuclei, I will describe rather detailed network calculations that suggest this neutrino process'' is an important nucleosynthesis mechanisms that may be responsible for the galactic abundances of {sup 7}Li, {sup 11}B, {sup 19}F, {sup 138}La, {sup 180}Ta, and a number of other nuclei. I also discuss the possibility of an r-process in the He zone of a low-Z progenitor that could be driven, in part, by neutrinos.

Haxton, W.C.

1991-01-01T23:59:59.000Z

200

The neutrino process and neutrino r-process  

SciTech Connect

Almost all of the 3 {center_dot} 10{sup 53} ergs released in a core-collapse supernova is carried off by the neutrinos emitted from the cooling neutron star. These neutrinos can excite nuclei in the mantle of the star by their neutral and charged current reactions, leading to the spallation of nucleonsa and {alpha}-particles and the production of new daughter nuclei, I will describe rather detailed network calculations that suggest this ``neutrino process`` is an important nucleosynthesis mechanisms that may be responsible for the galactic abundances of {sup 7}Li, {sup 11}B, {sup 19}F, {sup 138}La, {sup 180}Ta, and a number of other nuclei. I also discuss the possibility of an r-process in the He zone of a low-Z progenitor that could be driven, in part, by neutrinos.

Haxton, W.C.

1991-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "tau neutrinos heavy" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Constraining neutrino magnetic moment with solar and reactor neutrino data  

E-Print Network (OSTI)

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 MUNU in our analysis, improving significantly the current constraints on TMs. A comparison with previous works shows that our bounds are the strongest and most general results presented up to now. Finally, we perform a simulation of the future Borexino experiment and show that it will improve the bounds from today's data by order of magnitude.

M. A. Tortola

2004-01-19T23:59:59.000Z

202

Evidence for neutrino oscillations in the Sudbury Neutrino Observatory  

E-Print Network (OSTI)

the neutrinos from a nuclear reactor by the Cl 37 ( , e ? )the Savannah River nuclear reactor in 1956 [9]. Here Reinessources include nuclear reactors and the decays of cosmic-

Marino, Alysia Diane

2004-01-01T23:59:59.000Z

203

Neutrino Physics at the Turn of the Millenium  

E-Print Network (OSTI)

Recent solar & atmospheric nu-data strongly indicate need for physics beyond the Standard Model. I review the ways of reconciling them in terms of 3-nu oscillations. Though not implied by data, bi-maximal nu-mixing models emerge as a possibility. SUSY with broken R-parity provides an attractive way to incorporate it, opening the possibility of testing nu-anomalies at high- energy colliders such as the LHC or at the upcoming long-baseline or nu- factory experiments. Reconciling, in addition, the LSND hint requires a fourth, light sterile neutrino, nus. The simplest are the most symmetric scenarios, in which 2 of the 4 neutrinos are maximally-mixed and lie at the LSND scale, while the others are at the solar scale. The lightness of nus, the nearly maximal atmospheric mixing, and the solar/atmospheric splittings all follow naturally from the assumed lepton-number symmetry and its breaking. These basic schemes can be distinguished at neutral-current-sensitive solar & atmospheric neutrino experiments such as SNO. However underground experiments have not yet proven neutrino masses, as there are many alternatives. For example flavour changing interactions can play an important role in the explanation of solar and contained atmospheric data and could be tested e.g through \\mu \\to e + \\gamma, \\mu-e conversion in nuclei, unaccompanied by neutrino-less double beta decay. Conversely, a short-lived numu might play a role in the explanation of the atmospheric data. Finally, in the presence of a nus, a long-lived heavy nutau could delay the time at which the matter and radiation contributions to the energy density of the Universe become equal, reducing density fluctuations on smaller scales, thus saving the standard CDM scenario, while the light nue, numu and nus would explain the solar & atmospheric data.

J. W. F. Valle

1999-11-03T23:59:59.000Z

204

Neutrino mass hierarchy extraction using atmospheric neutrinos in ice  

E-Print Network (OSTI)

We show that the measurements of 10 GeV atmospheric neutrinos by an upcoming array of densely packed phototubes buried deep inside the IceCube detector at the South Pole can be used to determine the neutrino mass hierarchy for values of sin^2(2theta13) close to the present bound, if the hierarchy is normal. These results are obtained for an exposure of 100 Mton years and systematic uncertainties up to 10%.

Olga Mena; Irina Mocioiu; Soebur Razzaque

2008-03-20T23:59:59.000Z

205

Neutrino-pair emission from nuclear de-excitation in core-collapse supernova simulations  

E-Print Network (OSTI)

We study the impact of neutrino-pair production from the de-excitation of highly excited heavy nuclei on core-collapse supernova simulations, following the evolution up to several 100 ms after core bounce. Our study is based on the AGILE-Boltztran supernova code, which features general relativistic radiation hydrodynamics and accurate three-flavor Boltzmann neutrino transport in spherical symmetry. In our simulations the nuclear de-excitation process is described in two different ways. At first we follow the approach proposed by Fuller and Meyer [Astrophys. J. 376,701 (1991)], which is based on strength functions derived in the framework of the nuclear Fermi-gas model of non-interacting nucleons. Secondly, we parametrize the allowed and forbidden strength distributions in accordance with measurements for selected nuclear ground states. We determine the de-excitation strength by applying the Brink hypothesis and detailed balance. For both approaches, we find that nuclear de-excitation has no effect on the supernova dynamics. However, we find that nuclear de-excitation is the leading source for the production of electron antineutrinos as well as heavy-lepton flavor (anti)neutrinos during the collapse phase. At sufficiently high densities, the associated neutrino spectra are influenced by interactions with the surrounding matter, making proper simulations of neutrino transport important for the determination of the neutrino-energy loss rate. We find that even including nuclear de-excitations, the energy loss during the collapse phase is overwhelmingly dominated by electron neutrinos produced by electron captures.

Tobias Fischer; Karlheinz Langanke; Gabriel Martinez-Pinedo

2013-09-17T23:59:59.000Z

206

neutrino-properties-web.dvi  

NLE Websites -- All DOE Office Websites (Extended Search)

THE THE NEUTRINO PROPERTIES LISTINGS Revised August 2013 by P. Vogel (Caltech) and A. Piepke (University of Alabama). The following Listings concern measurements of various properties of neutrinos. Nearly all of the measurements, all of which so far are limits, actually concern superpositions of the mass eigenstates ν i , which are in turn related to the weak eigenstates ν ℓ , via the neutrino mixing matrix |ν ℓ = i U ℓi |ν i . In the analogous case of quark mixing via the CKM matrix, the smallness of the off-diagonal terms (small mixing angles) permits a "dominant eigenstate" approximation. However, the results of neutrino oscillation searches show that the mixing matrix contains two large mixing angles and a third angle that is not exceedingly small. We cannot, therefore, associate any particular state |ν i with any particular lepton label e, µ or τ . Nevertheless,

207

Neutrinos interacting with Polarizable Media  

E-Print Network (OSTI)

We study Cherenkov and transition radiation of neutral spin 1/2 particles which carry magnetic moments or electric dipole moments. In particular, we estimate the radiation caused by the solar neutrino flux in dielectric media.

W. Grimus; H. Neufeld

1994-10-20T23:59:59.000Z

208

Neutrino capital of the world  

E-Print Network (OSTI)

Neutrinos are ubiquitous particles, but they don't like to mingle. Each second, billions of them pass through our bodies, slicing imperceptibly through our delicate internal organs. They can barrel through the sun, stars, ...

Johnson, Carolyn Y., 1980-

2004-01-01T23:59:59.000Z

209

The Fermilab neutrino beam program  

Science Conference Proceedings (OSTI)

This talk presents an overview of the Fermilab Neutrino Beam Program. Results from completed experiments as well as the status and outlook for current experiments is given. Emphasis is given to current activities towards planning for a future program.

Rameika, Regina A.; /Fermilab

2007-01-01T23:59:59.000Z

210

Lepton Universality, |V(Us)| and Search for Second Class Current in Tau Decays  

SciTech Connect

Several hundred million {tau} decays have been studied with the BABAR detector at the PEP-II e{sup +}e{sup -} collider at the SLAC National Accelerator Laboratory. Recent results on Charged Current Lepton Universality and two independent measurements of |V{sub us}| using {tau}{sup -} {yields} e{sup -}{bar {nu}}{sub e}{nu}{sub {tau}}, {mu}{sup -}{bar {nu}}{sub {mu}}{nu}{sub {tau}}, {pi}{sup -}{nu}{sub {tau}}, K{sup -} {nu}{sub {tau}} and K{sub S}{sup 0}{pi}{sup -} {nu}{sub {tau}} decays, and a search for Second Class Current in {tau}{sup -} {yields} {pi}{sup -} {omega}{nu}{sub {tau}} decays are presented, where the charge conjugate decay modes are also implied.

Banerjee, Swagato; /Victoria U.

2011-11-10T23:59:59.000Z

211

Probing Radiative Solar Neutrinos Decays  

E-Print Network (OSTI)

Motivated by a pilot experiment conducted by F.Vannucci et al. during a solar eclipse, we work out the geometry governing the radiative decays of solar neutrinos. Surprisingly, although a smaller proportion of the photons can be detected, the case of strongly non-degenerate neutrinos brings better limits in terms of the fundamental couplings. We advocate satellite-based experiments to improve the sensitivity.

Frre, J M

1998-01-01T23:59:59.000Z

212

Solar Neutrinos: Status and Prospects  

E-Print Network (OSTI)

We describe the current status of solar neutrino measurements and of the theory -- both neutrino physics and solar astrophysics -- employed in interpreting measurements. Important recent developments include Super-Kamiokande's determination of the neutrino-electron elastic scattering rate for 8B neutrinos to 3%; the latest SNO global analysis in which the inclusion of low-energy data from SNO I and II significantly narrowed the range of allowed values for the neutrino mixing angle theta12; Borexino results for both the 7Be and pep neutrino fluxes, the first direct measurements constraining the rate of ppI and ppII burning in the Sun; global reanalyses of solar neutrino data that take into account new reactor results on theta13; a new decadal evaluation of the nuclear physics of the pp chain and CNO cycle defining best values and uncertainties in the nuclear microphysics input to solar models; recognition of an emerging discrepancy between two tests of solar metallicity, helioseismological mappings of the sound speed in the solar interior, and analyses of the metal photoabsorption lines based on our best current description of the Sun's photosphere; a new round of standard solar model calculations optimized to agree either with helioseismology or with the new photospheric analysis; and, motivated by the solar abundance problem, the development of nonstandard, accreting solar models, in order to investigate possible consequences of the metal segregation that occurred in the proto-solar disk. We review this progress and describe how new experiments such as SNO+ could help us further exploit neutrinos as a unique probe of stellar interiors.

W. C. Haxton; R. G. Hamish Robertson; Aldo M. Serenelli

2012-08-28T23:59:59.000Z

213

Solar mass-varying neutrino oscillations  

E-Print Network (OSTI)

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

V. Barger; Patrick Huber; Danny Marfatia

2005-02-21T23:59:59.000Z

214

Masatoshi Koshiba and Cosmic Neutrinos  

Office of Scientific and Technical Information (OSTI)

Masatoshi Koshiba and Cosmic Neutrinos Masatoshi Koshiba and Cosmic Neutrinos Resources with Additional Information Masatoshi Koshiba Courtesy of Sebastian Brandt 'The 2002 Nobel Prize in Physics has been awarded to ... Masatoshi Koshiba of the International Center for Elementary Particle Physics at the University of Tokyo in Japan, ... "for pioneering contributions to astrophysics, in particular for the detection of cosmic neutrinos." ... Neutrinos are important in astrophysics since they might have played a considerable role in shaping early galaxies; they are the form of energy coming directly from the solar core; and they account for the largest share of energy released during supernova explosions....'1 ...Koshiba, professor emeritus at the University of Tokyo, received his doctorate from the University of Rochester in [1955]. This year [2000], he is the co-recipient of the Wolf Prize in Physics, considered second only to the Nobel Prize in prestige, for his discovery that neutrinos have mass. Neutrinos are tiny particles smaller than atoms, and Koshiba's discovery is being hailed for its ramifications in the study of astronomical objects and the fundamental properties of matter, helping scientists to understand the birth of the universe. Koshiba started his career as a research associate at the University of Rochester, then went on to teach at the University of Tokyo." 2

215

Atmospheric Neutrinos in the MINOS Far Detector  

Science Conference Proceedings (OSTI)

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

Howcroft, Caius L.F.; /Cambridge U.

2004-12-01T23:59:59.000Z

216

Neutrino factories: realization and physics potential  

SciTech Connect

Neutrino Factories offer an exciting option for the long-term neutrino physics program. This new type of neutrino facility will provide beams with unique properties. Low systematic uncertainties at a Neutrino Factory, together with a unique and precisely known neutrino flavor content, will enable neutrino oscillation measurements to be made with unprecedented sensitivity and precision. Over recent years, the resulting neutrino factory physics potential has been discussed extensively in the literature. In addition, over the last six years the R&D necessary to realize a Neutrino Factory has been progressing, and has developed into a significant international activity. It is expected that, within about five more years, the initial phase of this R&D program will be complete and, if the community chooses to build this new type of neutrino source within the following decade, neutrino factory technology will be ready for the final R&D phase prior to construction. In this paper (1) an overview is given of the technical ingredients needed for a Neutrino Factory, (2) beam properties are described, (3) the resulting neutrino oscillation physics potential is summarized, (4) a more detailed description is given for one representative Neutrino Factory design, and (5) the ongoing R&D program is summarized, and future plans briefly described.

Geer, S.; /Fermilab; Zisman, M.S.; /LBL, Berkeley

2006-12-01T23:59:59.000Z

217

Measurement of Cabibbo suppressed decays of the $\\tau$ lepton  

E-Print Network (OSTI)

Branching ratios for the dominant Cabibbo-suppressed decays of the \\tau lepton have been measured by CLEO~II in e^+ e^- annihilation at CESR (\\sqrt{s} \\sim 10.6~GeV) using kaons with momenta below 0.7\\ \\rm GeV/c. The inclusive branching ratio into one charged kaon is (1.60 \\pm 0.12 \\pm 0.19)\\%. For the exclusive decays, B(\\tau \\to K^-) = (0.66 \\pm 0.07 \\pm 0.09)\\%, B(\\tau \\to K^- \\pi^0) = (0.51 \\pm 0.10 \\pm 0.07)\\%, and, based on three events, B(\\tau \\to K^- \\pi^0 \\pi^0) < 0.3\\% at the 90\\% confidence level. These represent significant improvements over previous results. B(\\tau\\to K^- \\pi^0) is measured for the first time with exclusive \\pi^0 reconstruction. hardcopies with figures can be obtained by writing to: Pam Morehouse preprint secretary Newman Lab Cornell University Ithaca, NY 14853 or by sending mail to: preprints@lns62.lns.cornell.edu

Battle, M; Kwon, Y; Roberts, S; Thorndike, E H; Wang, C H; Dominick, J; Lambrecht, M; Sanghera, S; Shelkov, V; Skwarnicki, T; Stroynowski, R; Volobuev, I P; Wei, G; Zadorozhny, P; Artuso, M; Goldberg, M; He, D; Horwitz, N; Kennett, R; Mountain, R; Moneti, G C; Muheim, F; Mukhin, Y; Playfer, S; Rozen, Y; Stone, S; Thulasidas, M; Vasseur, G; Zhu, G; Bartelt, J; Csorna, S E; Egyed, Z; Jain, V; Kinoshita, K; Edwards, K W; Ogg, M; Britton, D I; Hyatt, E R F; MacFarlane, D B; Patel, P M; Akerib, D S; Barish, B C; Chadha, M; Chan, S; Cowen, D F; Eigen, G; Miller, J S; O'Grady, C; Urheim, J; Weinstein, A J; Acosta, D; Athanas, M; Masek, G E; Paar, H P; Sivertz, M; Gronberg, J B; Kutschke, R; Menary, S R; Morrison, R J; Nakanishi, S; Nelson, H N; Nelson, T K; Qiao, C; Richman, J D; Ryd, A; Tajima, H; Sperka, D; Witherell, M S; Procario, M; Balest, R; Cho, K; Daoudi, M; Ford, W T; Johnson, D R; Lingel, K; Lohner, M; Rankin, P; Smith, J G; Alexander, J P; Bebek, C; Berkelman, K; Bloom, K; Browder, T E; Cassel, David G; Cho, H A; Coffman, D M; Drell, P S; Ehrlich, R; Gaidarev, P B; Galik, R S; Garca-Sciveres, M; Geiser, B; Gittelman, B; Gray, S W; Hartill, D L; Heltsley, B K; Jones, C D; Jones, S L; Kandaswamy, J; Katayama, N; Kim, P C; Kreinick, D L; Ludwig, G S; Masui, J; Mevissen, J; Mistry, N B; Ng, C R; Nordberg, E; Patterson, J R; Peterson, D; Riley, D; Salman, S; Sapper, M; Wrthwein, F; Avery, P; Freyberger, A P; Rodrguez, J; Stephens, R; Yang, S; Yelton, J; Cinabro, D; Henderson, S; Liu, T; Saulnier, M; Wilson, R; Yamamoto, H; Bergfeld, T; Eisenstein, B I; Gollin, G; Ong, B; Palmer, M; Selen, M; Thaler, J J; Sadoff, A J; Ammar, R; Ball, S; Baringer, P; Bean, A; Besson, D; Coppage, D; Copty, N K; Davis, R; Hancock, N; Kelly, M; Kwak, N; Lam, H; Kubota, Y; Lattery, M; Nelson, J K; Patton, S; Perticone, D; Poling, R A; Savinov, V; Schrenk, S; Wang, R; Alam, M S; Kim, I J; Nemati, B; O'Neill, J J; Severini, H; Sun, C R; Zoeller, M M; Crawford, G; Daubenmier, C M; Fulton, R; Fujino, D; Gan, K K; Honscheid, K; Kagan, H; Kass, R; Lee, J; Malchow, R L; Skovpen, Y; Sung, M; White, C; Butler, F; Fu, X; Kalbfleisch, G R; Ross, W R; Skubic, P L; Snow, J; Wang, P L; Wood, M; Brown, D N; Fast, J; McIlwain, R L; Miao, T; Miller, D H; Modesitt, M; Payne, D; Shibata, E I; Shipsey, I P J; Wang Pei Ning

1994-01-01T23:59:59.000Z

218

Solar Neutrino Oscillation Parameters in Experiments with Reactor Anti-Neutrinos  

E-Print Network (OSTI)

We review the current status of the solar neutrino oscillation parameters. We discuss the conditions under which measurements from future solar neutrino experiments would determine the oscillation parameters precisely. Finally we expound the potential of long baseline reactor anti-neutrino experiments in measuring the solar neutrino oscillation parameters.

Sandhya Choubey

2004-02-27T23:59:59.000Z

219

Los Alamos Science, Number 25 -- 1997: Celebrating the Neutrino  

DOE R&D Accomplishments (OSTI)

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.

Cooper, N. G. [ed.

1997-00-00T23:59:59.000Z

220

Measurement of theta13 with reactor neutrinos  

E-Print Network (OSTI)

? detectors ~1 km nuclear reactor Figure 2. Concept of a 2-Measurement of ? 13 with Reactor Neutrinos K.M. Heeger a ,power plant, a future reactor neutrino experiment has the

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

2004-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "tau neutrinos heavy" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Solar Neutrinos: Models, Observations, and New Opportunities  

E-Print Network (OSTI)

I discuss the development and resolution of the solar neutrino problem, as well as opportunities now open to us to extend our knowledge of main-sequence stellar evolution and neutrino astrophysics.

W. C. Haxton

2007-10-11T23:59:59.000Z

222

Neutrino mixing, flavor states and dark energy  

E-Print Network (OSTI)

We shortly summarize the quantum field theory formalism for the neutrino mixing and report on recent results showing that the vacuum condensate induced by neutrino mixing can be interpreted as a dark energy component of the Universe.

M. Blasone; A. Capolupo; S. Capozziello; G. Vitiello

2007-11-06T23:59:59.000Z

223

Measurement of the branching fraction for $\\tau\\to\\eta K\  

SciTech Connect

The authors report on analyses of tau lepton decays {tau}{sup -} {yields} {eta}K{sup -}{nu}{sub {tau}} and {tau}{sup -} {yields} {eta}{pi}{sup -}{nu}{sub {tau}}, with {eta} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0}, using 470 fb{sup -1} of data from the BABAR experiment at PEP-II, collected at center-of-mass energies at and near the {Upsilon}(4S) resonance. They measure the branching fraction for the {tau}{sup -} {yields} {eta}K{sup -}{nu}{sub {tau}} decay mode, {Beta}({tau}{sup -} {yields} {eta}K{sup -}{nu}{sub {tau}}) = (1.42 {+-} 0.11(stat) {+-} 0.07(syst)) x 10{sup -4}, and report a 95% confidence level upper limit for the second-class current process {tau}{sup -} {yields} {eta}{pi}{sup -}{nu}{sub {tau}}, {Beta}({tau}{sup -} {yields} {eta}{pi}{sup -}{nu}{sub {tau}}) < 9.9 x 10{sup -5}.

del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Battaglia, M.; Brown, D.N.; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; Tanabe, T.; /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Indian Inst. Tech., Guwahati /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Paris U., VI-VII /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

2011-08-12T23:59:59.000Z

224

Solar neutrinos with three flavor mixings  

SciTech Connect

The recent{sup 71}Ga solar neutrino observation is combined with the {sup 37}Cl and Kamiokande-II observations in an analysis for neutrino masses and mixings. The allowed parameter region is found for matter enhanced mixings among all three neutrino flavors. Distortions of the solar neutrino spectrum unique to three flavors are possible and may be observed in continuing and next generation experiments.

Harley, D.; Pantaleone, J. [Washington Univ., Seattle, WA (United States). Inst. for Nuclear Theory; Kuo, T.K. [Purdue Univ., Lafayette, IN (United States). Dept. of Physics

1992-12-31T23:59:59.000Z

225

Solar neutrinos with three flavor mixings  

SciTech Connect

The recent[sup 71]Ga solar neutrino observation is combined with the [sup 37]Cl and Kamiokande-II observations in an analysis for neutrino masses and mixings. The allowed parameter region is found for matter enhanced mixings among all three neutrino flavors. Distortions of the solar neutrino spectrum unique to three flavors are possible and may be observed in continuing and next generation experiments.

Harley, D.; Pantaleone, J. (Washington Univ., Seattle, WA (United States). Inst. for Nuclear Theory); Kuo, T.K. (Purdue Univ., Lafayette, IN (United States). Dept. of Physics)

1992-01-01T23:59:59.000Z

226

Atmospheric neutrino flux at INO site  

Science Conference Proceedings (OSTI)

To illustrate the calculation of the atmospheric neutrino flux, we briefly explain our calculation scheme and important components, such as primary cosmic ray spectra, interaction model, and geomagnetic model. Then, we calculate the atmospheric neutrino flux at INO site in our calculation scheme. We compare the calculated atmospheric neutrino fluxes predicted at INO with those at other major neutrino detector sites, especially that at SK site.

Honda, Morihiro [Institute for Cosmic Ray Research, University of Tokyo, 5-1-5 Kashiwa-no-ha, Kashiwa, Chiba 277-8582 (Japan)

2011-11-23T23:59:59.000Z

227

Neutrino magnetic moment in a magnetized plasma  

E-Print Network (OSTI)

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

N. V. Mikheev; E. N. Narynskaya

2010-11-08T23:59:59.000Z

228

On Ultrahigh-energy Neutrino Scattering  

E-Print Network (OSTI)

We predict the neutrino-nucleon cross section at ultrahigh energies relevant in connection with the search for high-energy cosmic neutrinos. Our investigation, employing the color-dipole picture, among other things allows us to quantitatively determine which fraction of the ultrahigh-energy neutrino-nucleon cross section stems from the saturation versus the color transparency region. We disagree with various results in the literature that predict a strong suppression of the neutrino-nucleon cross section at ultrahigh energies.

Kuroda, Masaaki

2013-01-01T23:59:59.000Z

229

Dark energy induced by neutrino mixing  

E-Print Network (OSTI)

The energy content of the vacuum condensate induced by the neutrino mixing is interpreted as dynamically evolving dark energy.

Antonio Capolupo; Salvatore Capozziello; Giuseppe Vitiello

2006-12-05T23:59:59.000Z

230

The Lake Baikal neutrino experiment: selected results  

E-Print Network (OSTI)

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

BAIKAL Collaboration; V. Balkanov

2000-01-10T23:59:59.000Z

231

Neutrino Masses and Oscillations: Triumphs and Challenges  

E-Print Network (OSTI)

The recent progress in establishing the existence of finite neutrino masses and mixing between generations of neutrinos has been remarkable, if not astounding. The combined results from studies of atmospheric neutrinos, solar neutrinos, and reactor antineutrinos paint an intriguing picture for theorists and provide clear motivation for future experimental studies. In this review, we summarize the status of experimental and theoretical work in this field and explore the future opportunities that emerge in light of recent discoveries.

R. D. McKeown; P. Vogel

2004-02-03T23:59:59.000Z

232

Solar Neutrinos with Super-Kamiokande  

E-Print Network (OSTI)

The discrepancy of the measured solar neutrino flux compared to the predictions of the standard solar model may be explained by the neutrino flavor oscillation hypothesis. A more direct and less model-dependent test of this hypothesis is a measurement of the distortion of the shape of the solar neutrino energy spectrum. Super-Kamiokande studies the energy spectrum of recoil electrons from solar neutrino scattering in water above 5.5 MeV.

Smy, M B

1999-01-01T23:59:59.000Z

233

Studies of the Strange Hadronic Tau Decay Tau- to K0(S) Pi- Nu-Tau Using the BaBar Detector  

SciTech Connect

A study of the decay {tau}{sup -} {yields} K{sub S}{sup 0}{pi}{sup -} {nu}{sub {tau}} (K{sub S}{sup 0} {yields} {pi}{sup +}{pi}{sup -}) using the BABAR detector is presented. Using 124.4 fb{sup -1} of data we measure {Beta}({tau}{sup -} {yields} {bar K}{sup 0}{pi}{sup -}{nu}{sub {tau}}) = (0.830 {+-} 0.005(stat) {+-} 0.042(syst))%, which is the world's most precise measurement to date of this branching ratio, and is consistent with the current world average. This preliminary result, unlike most of the {Beta}({tau}{sup -} {yields} {bar K}{sup 0}{pi}{sup -}{nu}{sub {tau}}) measurements already published, is systematics dominated and so the biggest future improvement to this number should come from reducing the systematic uncertainties in the analysis. A study of the K{pi} mass spectrum, from which the strange (K{pi}) spectral function can be measured, reveals excess contributions above the K*(892) tail at higher K{pi} mass. While in the past this has been thought to be due to K*(892) - K*(1410) interference, we find that the K*(1410), whose branching ratio to K{pi} is approximately 7%, seems insufficient to explain the excess mass observed in the data. Instead, we perform a fit using a K*(892) - K*(1680) interference model and find better agreement. The discrepancy that remains could be due to an s-wave contribution to the interference that is not parameterized in the model used, and/or detector smearing that is not accounted for in our fit. We also attempt to find an s-wave contribution to the K{pi} mass spectrum by searching for an sp-interference effect. While we find a hint that such an effect exists, we have neither the confidence in the statistics nor systematics in the higher K{pi} mass region to announce an observation. We conclude that it would be a worthwhile study to pursue.

Lyon, Andrew J.; /Manchester U. /SLAC

2006-01-27T23:59:59.000Z

234

Neutrino properties from reactor and accelerator experiments  

E-Print Network (OSTI)

In this talk, I discuss the general theory of neutrino oscillation experiments, putting special emphasis on the momentum distribution of the incoming neutrino beam. Then I discuss recent neutrino oscillation experiments, viz., LSND, KARMEN and CHOOZ. Experiments foreseeable in the near future have also been discussed at the end.

Pal, P B

1998-01-01T23:59:59.000Z

235

Neutrinos and Non-proliferation in Europe  

E-Print Network (OSTI)

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

Cribier, Michel

2006-01-01T23:59:59.000Z

236

SOLAR NEUTRINOS: WHERE WE ARE JOHN BAHCALL  

E-Print Network (OSTI)

SOLAR NEUTRINOS: WHERE WE ARE JOHN BAHCALL Institute for Advanced Study, Princeton, NJ 08540 This talk compares standard model predictions for solar neutrino experiments with the results of actual a standard solar model. I emphasize the importance of recent analyses in which the neutrino fluxes

Bahcall, John

237

Neutrino oscillations present status and outlook  

E-Print Network (OSTI)

I summarize the status of three-flavour neutrino oscillations with date of Oct. 2007, and provide an outlook for the developments to be expected in the near future. Furthermore, I discuss the status of sterile neutrino oscillation interpretations of the LSND anomaly in the light of recent MiniBooNE results, and comment on implications for the future neutrino oscillation program.

Schwetz, Thomas

2008-01-01T23:59:59.000Z

238

Neutrino oscillations: present status and outlook  

E-Print Network (OSTI)

I summarize the status of three-flavour neutrino oscillations with date of Oct. 2007, and provide an outlook for the developments to be expected in the near future. Furthermore, I discuss the status of sterile neutrino oscillation interpretations of the LSND anomaly in the light of recent MiniBooNE results, and comment on implications for the future neutrino oscillation program.

Thomas Schwetz

2007-10-26T23:59:59.000Z

239

Neutrino oscillations: present status and outlook  

Science Conference Proceedings (OSTI)

I summarize the status of three-flavour neutrino oscillations with date of Oct. 2007, and provide an outlook for the developments to be expected in the near future. Furthermore, I discuss the status of sterile neutrino oscillation interpretations of the LSND anomaly in the light of recent MiniBooNE results, and comment on implications for the future neutrino oscillation program.

Schwetz, Thomas [Physics Department, Theory Division, CERN, CH-1211 Geneva 23 (Switzerland)

2008-02-21T23:59:59.000Z

240

Reactor-based Neutrino Oscillation Experiments  

E-Print Network (OSTI)

The status of neutrino oscillation searches employing nuclear reactors as sources is reviewed. This technique, a direct continuation of the experiments that proved the existence of neutrinos, is today an essential tool in investigating the indications of oscillations found in studying neutrinos produced in the sun and in the earth's atmosphere. The low-energy of the reactor \

Carlo Bemporad; Giorgio Gratta; Petr Vogel

2001-07-26T23:59:59.000Z

Note: This page contains sample records for the topic "tau neutrinos heavy" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Neutrinos from Gamma Ray Bursts  

E-Print Network (OSTI)

The observed fluxes of cosmic rays and gamma rays are used to infer the maximum allowed high-energy neutrino flux allowed for Gamma Ray Bursts (GRBs), following Mannheim, Protheroe, and Rachen (2000). It is shown that if GRBs produce the ultrahigh-energy cosmic rays, they should contribute (a) at least 10% of the extragalactic gamma ray background between 3 MeV and 30 GeV, contrary to their observed energy flux which is only a minute fraction of this flux, and (b) a cumulative neutrino flux a factor of 20 below the AMANDA (Neutrino 2000) limit on isotropic neutrinos. This could have two implications, either GRBs do not produce the ultrahigh energy cosmic rays or that the GRBs are strongly beamed and emit most of their power at energies well above 100 GeV implausibly increasing the energy requirements, but consistent with the marginal detections of a few low-redshift GRBs by MILAGRITO, HEGRA-AIROBICC, and the Tibet-Array. All crucial measurements to test the models will be available in the next few years. These are measurements of (i) high-energy neutrinos with AMANDA-ICECUBE or an enlarged ANTARES/NESTOR ocean detector, (ii) GRB redshifts from HETE-2 follow-up studies, and (iii) GRB spectra above 10 GeV with low-threshold imaging air Cherenkov telescopes such as MAGIC and the space telescopes AGILE and GLAST.

Karl Mannheim

2000-10-18T23:59:59.000Z

242

Computational studies of tau protein : implications for the pathogenesis and treatment of neurodegenerative diseases  

E-Print Network (OSTI)

Tau protein is the primary constituent of protein aggregates known as neurofibrillary tangles, a pathological hallmark of Alzheimer's disease (AD). Previous studies suggest that tau protein may play a contributing role in ...

Huang, Austin V., 1980-

2009-01-01T23:59:59.000Z

243

Do hep neutrinos affect the solar neutrino energy spectrum?  

E-Print Network (OSTI)

If the low energy cross section for 3He + p goes to 4He + e + nu_e, the `hep' reaction, is > 20 times larger than the best (but uncertain) theoretical estimates, then this reaction could significantly influence the electron energy spectrum produced by solar neutrino interactions and measured in the SuperKamiokande, SNO, and ICARUS experiments. We compare predicted energy spectra for different assumed hep fluxes and different neutrino oscillation scenarios with the observed SuperKamiokande spectrum. The spectra with enhanced hep contributions provide better fits to the SuperKamiokande data.

John Bahcall; Plamen Krastev

1998-07-29T23:59:59.000Z

244

Neutrino oscillations in noisy media  

SciTech Connect

The authors develop the Redfield equation for delta-correlated gaussian noise and apply it to the case of two neutrino flavor or spin precession in the presence of a noisy matter density or magnetic field, respectively. The criteria under which physical fluctuations can be well approximated by the delta-correlated gaussian noise for the above cases are examined. Current limits on the possible neutrino magnetic moment and solar magnetic field suggest that a reasonably noisy solar magnetic field would not appreciably affect the solar electron neutrino flux. However, if the solar electron density has fluctuations of a few percent of the local density and a small enough correlation length, the MSW effect is suppressed for a range of parameters.

Loreti, F.N.; Balantekin, A.B.

1994-05-27T23:59:59.000Z

245

On solar neutrino fluxes in radiochemical experiments  

E-Print Network (OSTI)

We analyze fluctuations of the solar neutrino flux using data from the Homestake, GALLEX, GNO, SAGE and Super Kamiokande experiments. Spectral analysis and direct quantitative estimations show that the most stable variation of the solar neutrino flux is a quasi-five-year periodicity. The revised values of the mean solar neutrino flux are presented in Table 4. They were used to estimate the observed pp-flux of the solar electron neutrinos near the Earth. We consider two alternative explanations for the origin of a variable component of the solar neutrino deficit.

R. N. Ikhsanov; Yu. N. Gnedin; E. V. Miletsky

2005-12-08T23:59:59.000Z

246

Measuring Neutrinos with the ANTARES Telescope  

Science Conference Proceedings (OSTI)

The ANTARES underwater neutrino telescope has been taking data since construction began in 2006. The telescope, completed in May of 2008, detects the Cerenkov radiation of charged leptons produced by high energy neutrinos interacting in or around the detector. The lepton trajectory is reconstructed with high precision, revealing the direction of the incoming neutrino. The performance of the detector will be discussed and recent data showing muons, electromagnetic showers and atmospheric neutrinos will be presented. Studies have been underway to search for neutrino point sources in the ANTARES data since 2007. Results from these studies will be presented, and the sensitivity of the telescope will be discussed.

Reed, Corey [National Institute for Subatomic Physics (Nikhef), Amsterdam (Netherlands)

2009-12-17T23:59:59.000Z

247

First search for atmospheric and extraterrestrial neutrino-induced cascades with the IceCube detector  

SciTech Connect

We report on the first search for atmospheric and for diffuse astrophysical neutrino-induced showers (cascades) in the IceCube detector using 257 days of data collected in the year 2007-2008 with 22 strings active. A total of 14 events with energies above 16 TeV remained after event selections in the diffuse analysis, with an expected total background contribution of 8.3{+-}3.6. At 90% confidence we set an upper limit of E{sup 2}{Phi}{sub 90%CL}<3.6x10{sup -7} GeV{center_dot}cm{sup -2}{center_dot}s{sup -1}{center_dot}sr{sup -1} on the diffuse flux of neutrinos of all flavors in the energy range between 24 TeV and 6.6 PeV assuming that {Phi}{proportional_to}E{sup -2} and the flavor composition of the {nu}{sub e} ratio {nu}{sub {mu}} ratio {nu}{sub {tau}} flux is 1 ratio 1 ratio 1 at the Earth. The atmospheric neutrino analysis was optimized for lower energies. A total of 12 events were observed with energies above 5 TeV. The observed number of events is consistent with the expected background, within the uncertainties.

Abbasi, R.; Aguilar, J. A.; Andeen, K.; Baker, M.; BenZvi, S.; Berghaus, P.; Braun, J.; Chirkin, D.; Desiati, P.; Diaz-Velez, J. C.; Dumm, J. P.; Eisch, J.; Gladstone, L.; Grullon, S.; Halzen, F.; Hill, G. C.; Hoshina, K.; Jacobsen, J.; Karle, A.; Kelley, J. L. [Department of Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States)

2011-10-01T23:59:59.000Z

248

Pair Production of Tau Sneutrinos at Linear Colliders  

E-Print Network (OSTI)

The pair production of tau sneutrinos in $e^{+}e^{-}$ collisions and their subsequent decays are studied in a framework of the supersymmetric extension of the standard model. We present an analysis for the parameter space (BR vs. mass) which could be explored at the future high energy $e^{+}e^{-}$ colliders.

Ari, V

2010-01-01T23:59:59.000Z

249

Validating Quicksand: Schema Versioning in \\tauXSchema  

Science Conference Proceedings (OSTI)

The W3C XML Schema recommendation defines the structure and data types for XML documents, but lacks explicit support for time-varying XML documents or for a time-varying schema. In previous work we introduced \\tauXSchema which is an infrastructure and ...

Curtis Dyreson; Richard T. Snodgrass; Faiz Currim; Sabah Currim; Shailesh Joshi

2006-04-01T23:59:59.000Z

250

Hadronic decays of the tau lepton: Theoretical outlook  

E-Print Network (OSTI)

The structure of the form factors stemmed from the hadronization of QCD currents in the energy region of the resonances can be explored through the analyses of exclusive hadronic decays of the tau lepton. I give a short review on the later theoretical progress achieved in the description of experimental data.

J. Portoles

2007-02-13T23:59:59.000Z

251

Solar neutrinos and the sun  

E-Print Network (OSTI)

We present updated standard solar models (SSMs) that incorporate the latest results for nuclear fusion rates, recently published. We show helioseismic results for high and low metallicity compositions and also for an alternative set of solar abundance, derived from 3D model atmospheres, which give intermediate results. For the high and low metallicity models, we show that current solar neutrino data can not differentiate between models and that a measurement of the CNO fluxes is necessary to achieve that goal. A few additional implications of a hypothetical measurement of CNO neutrinos, both in terms of solar and stellar physics, are discussed.

Aldo Serenelli

2011-09-12T23:59:59.000Z

252

Stimulated Neutrino Transformation Through Turbulence  

E-Print Network (OSTI)

We derive an analytical solution for the flavor evolution of a neutrino through a turbulent density profile which is found to accurately predict the amplitude and transition wavelength of numerical solutions on a case-by-case basis. The evolution is seen to strongly depend upon those Fourier modes in the turbulence which are approximately the same as the splitting between neutrino eigenvalues and, unexpectedly, we also find a dependence upon the long wavelength modes when the ratio of their amplitude and the wavenumber is of order, or greater than, the first root of the Bessel function $J_0$.

Kelly M. Patton; James P. Kneller; Gail C. McLaughlin

2013-10-21T23:59:59.000Z

253

Solar neutrinos and the sun  

E-Print Network (OSTI)

We present updated standard solar models (SSMs) that incorporate the latest results for nuclear fusion rates, recently published. We show helioseismic results for high and low metallicity compositions and also for an alternative set of solar abundance, derived from 3D model atmospheres, which give intermediate results. For the high and low metallicity models, we show that current solar neutrino data can not differentiate between models and that a measurement of the CNO fluxes is necessary to achieve that goal. A few additional implications of a hypothetical measurement of CNO neutrinos, both in terms of solar and stellar physics, are discussed.

Serenelli, Aldo

2011-01-01T23:59:59.000Z

254

Searching for sterile neutrinos in ice  

E-Print Network (OSTI)

Oscillation interpretation of the results from the LSND, MiniBooNE and some other experiments requires existence of sterile neutrino with mass $\\sim 1$ eV and mixing with the active neutrinos $|U_{\\mu 0}|^2 \\sim (0.02 - 0.04)$. It has been realized some time ago that existence of such a neutrino affects significantly the fluxes of atmospheric neutrinos in the TeV range which can be tested by the IceCube Neutrino Observatory. In view of the first IceCube data release we have revisited the oscillations of high energy atmospheric neutrinos in the presence of one sterile neutrino. Properties of the oscillation probabilities are studied in details for various mixing schemes both analytically and numerically. The energy spectra and angular distributions of the $\

Soebur Razzaque; A. Yu. Smirnov

2011-04-07T23:59:59.000Z

255

Progress in the physics of massive neutrinos  

E-Print Network (OSTI)

The current status of the physics of massive neutrinos is reviewed with a forward-looking emphasis. The article begins with the general phenomenology of neutrino oscillations in vacuum and matter and documents the experimental evidence for oscillations of solar, reactor, atmospheric and accelerator neutrinos. Both active and sterile oscillation possibilities are considered. The impact of cosmology (BBN, CMB, leptogenesis) and astrophysics (supernovae, highest energy cosmic rays) on neutrino observables and vice versa, is evaluated. The predictions of grand unified, radiative and other models of neutrino mass are discussed. Ways of determining the unknown parameters of three-neutrino oscillations are assessed, taking into account eight-fold degeneracies in parameters that yield the same oscillation probabilities, as well as ways to determine the absolute neutrino mass scale (from beta-decay, neutrinoless double-beta decay, large scale structure and Z-bursts). Critical unknowns at present are the amplitude of \

V. Barger; D. Marfatia; K. Whisnant

2003-08-12T23:59:59.000Z

256

IMPACTS OF COLLECTIVE NEUTRINO OSCILLATIONS ON CORE-COLLAPSE SUPERNOVA EXPLOSIONS  

Science Conference Proceedings (OSTI)

By performing a series of one- and two-dimensional (1D and 2D) hydrodynamic simulations with spectral neutrino transport, we study possible impacts of collective neutrino oscillations on the dynamics of core-collapse supernovae. To model the spectral swapping, which is one of the possible outcome of the collective neutrino oscillations, we parameterize the onset time when the spectral swap begins, the radius where the spectral swap occurs, and the threshold energy above which the spectral interchange between heavy-lepton neutrinos and electron/anti-electron neutrinos takes place. By doing so, we systematically study how the neutrino heating enhanced by the spectral swapping could affect the shock evolution as well as the matter ejection. We also investigate the progenitor dependence using a suite of progenitor models (13, 15, 20, and 25 M{sub sun}). We find that there is a critical heating rate induced by the spectral swapping that triggers explosions, and which significantly differs between the progenitors. The critical heating rate is generally smaller for 2D than for 1D due to the multidimensionality that enhances the neutrino heating efficiency. For the progenitors employed in this paper, the final remnant masses are estimated to range between 1.1-1.5 M{sub sun}. For our 2D model of the 15 M{sub sun} progenitor, we find a set of oscillation parameters that could account for strong supernova explosions ({approx}10{sup 51} erg), simultaneously leaving behind a remnant mass close to {approx}1.4 M{sub sun}.

Suwa, Yudai [Yukawa Institute for Theoretical Physics, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto 606-8502 (Japan); Kotake, Kei [Division of Theoretical Astronomy, National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588 (Japan); Takiwaki, Tomoya [Center for Computational Astrophysics, National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588 (Japan); Liebendoerfer, Matthias [Department of Physics, University of Basel, Klingelbergstr. 82, CH-4056 Basel (Switzerland); Sato, Katsuhiko, E-mail: suwa@yukawa.kyoto-u.ac.jp [The Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa, Chiba 277-8568 (Japan)

2011-09-10T23:59:59.000Z

257

Light Sterile Neutrinos and Short Baseline Neutrino Oscillation Anomalies  

E-Print Network (OSTI)

We study two possible explanations for short baseline neutrino oscillation anomalies, such as the LSND and MiniBooNE anti-neutrino data, and for the reactor anomaly. The first scenario is the mini-seesaw mechanism with two eV-scale sterile neutrinos. We present both analytic formulas and numerical results showing that this scenario could account for the short baseline and reactor anomalies and is consistent with the observed masses and mixings of the three active neutrinos. We also show that this scenario could arise naturally from an effective theory containing a TeV-scale VEV, which could be related to other TeV-scale physics. The minimal version of the mini-seesaw relates the active-sterile mixings to five real parameters and favors an inverted hierarchy. It has the interesting property that the effective Majorana mass for neutrinoless double beta decay vanishes, while the effective masses relevant to tritium beta decay and to cosmology are respectively around 0.2 and 2.4 eV. The second scenario contains o...

Fan, JiJi

2012-01-01T23:59:59.000Z

258

The Neutrino Eye: A Megaton Low Energy Neutrino  

E-Print Network (OSTI)

, despite the evident truth of that statement, the history of the water Cherenkov detectors demonstrates requirements. After all, there are million ton oil tankers, and there are oil platforms of much larger.4.4 Supernovae Out to 2Mpc The entire history of extra­solar neutrino astronomy consists of the the few second

Learned, John

259

Solar Neutrinos: Solved and Unsolved Problems John N. Bahcall  

E-Print Network (OSTI)

Chapter 10 Solar Neutrinos: Solved and Unsolved Problems John N. Bahcall Institute for Advanced study solar neutrinos? What does the combined standard model (solar plus electroweak) predict for solar neutrinos? Why are the calculations of neutrino fluxes robust? What are the three solar neutrino problems

Bahcall, John

260

WHY DO SOLAR NEUTRINO EXPERIMENTS BELOW J. N. BAHCALL  

E-Print Network (OSTI)

V. The rare 8 B neutrino ux is the only solar neutrino source for which measurements of the energy have been quantities for low energy solar neutrinos is impor- tant and can be used to constrain models of the neutrino that can do everything. I think we should be happy if a low energy solar neutrino experiment can measure

Bahcall, John

Note: This page contains sample records for the topic "tau neutrinos heavy" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

WHY DO SOLAR NEUTRINO EXPERIMENTS BELOW J. N. BAHCALL  

E-Print Network (OSTI)

V. The rare 8 B neutrino flux is the only solar neutrino source for which measurements of the energy have been quantities for low energy solar neutrinos is impor- tant and can be used to constrain models of the neutrino that can do everything. I think we should be happy if a low energy solar neutrino experiment can measure

Bahcall, John

262

Heavy Oil Projects  

NLE Websites -- All DOE Office Websites (Extended Search)

Select Reports from Heavy Oil Projects Project Number Performer Title Heavy Oil Recovery US (NIPERBDM-0225) BDM-Oklahoma, Inc. Feasibility Study of Heavy Oil Recovery in the...

263

Lepton flavor violating Higgs bosons and {tau}{yields}{mu}{gamma}  

SciTech Connect

We update phenomenological constraints on a two Higgs doublet model with lepton flavor nonconserving Yukawa couplings. We review that tan{beta} is ambiguous in such 'type III' models, and define it from the {tau} Yukawa coupling. The neutral scalars {phi} could be searched for at hadron colliders in {phi}{yields}{tau}{mu} and are constrained by the rare decay {tau}{yields}{mu}{gamma}. The Feynman diagrams for the collider process, with Higgs production via gluon fusion, are similar to the two-loop ''Barr-Zee'' diagrams, which contribute to {tau}{yields}{mu}{gamma}. Some ''tuning'' is required to obtain a collider cross section of order the standard model expectation for {sigma}(gg{yields}h{sub SM{yields}{tau}}{sup +{tau}-}), while agreeing with the current bound from {tau}{yields}{mu}{gamma}.

Davidson, Sacha; Grenier, Gerald [IPNL, Universite de Lyon, Universite Lyon 1, CNRS/IN2P3, 4 rue E. Fermi 69622 Villeurbanne cedex (France)

2010-05-01T23:59:59.000Z

264

Probing the Absolute Mass Scale of Neutrinos  

SciTech Connect

The experimental efforts of the Neutrino Physics Group at MIT center primarily around the exploration of neutrino mass and its significance within the context of nuclear physics, particle physics, and cosmology. The group has played a prominent role in the Sudbury Neutrino Observatory, a neutrino experiment dedicated to measure neutrino oscillations from 8B neutrinos created in the sun. The group is now focusing its efforts in the measurement of the neutrino mass directly via the use of tritium beta decay. The MIT group has primary responsibilities in the Karlsruhe Tritium Neutrino mass experiment, expected to begin data taking by 2013. Specifically, the MIT group is responsible for the design and development of the global Monte Carlo framework to be used by the KATRIN collaboration, as well as responsibilities directly associated with the construction of the focal plane detector. In addition, the MIT group is sponsoring a new research endeavor for neutrino mass measurements, known as Project 8, to push beyond the limitations of current neutrino mass experiments.

Prof. Joseph A. Formaggio

2011-10-12T23:59:59.000Z

265

Neutrino-2008: Where are we? Where are we going?  

E-Print Network (OSTI)

Our present knowledge of neutrinos can be summarized in terms of the "standard neutrino scenario". Phenomenology of this scenario as well as attempts to uncover physics behind neutrino mass and mixing are described. Goals of future studies include complete reconstruction of the neutrino mass and flavor spectrum, further test of the standard scenario and search for new physics beyond it. Developments of new experimental techniques may lead to construction of new neutrino detectors from table-top to multi-Megaton scales which will open new horizons in the field. With detection of neutrino bursts from the Galactic supernova and high energy cosmic neutrinos neutrino astrophysics will enter qualitatively new phase. Neutrinos and LHC (and future colliders), neutrino astronomy, neutrino structure of the Universe, and probably, neutrino technologies will be among leading topics of research.

Alexei Yu. Smirnov

2008-10-15T23:59:59.000Z

266

Neutrino-2008: Where are we? Where are we going?  

E-Print Network (OSTI)

Our present knowledge of neutrinos can be summarized in terms of the "standard neutrino scenario". Phenomenology of this scenario as well as attempts to uncover physics behind neutrino mass and mixing are described. Goals of future studies include complete reconstruction of the neutrino mass and flavor spectrum, further test of the standard scenario and search for new physics beyond it. Developments of new experimental techniques may lead to construction of new neutrino detectors from table-top to multi-Megaton scales which will open new horizons in the field. With detection of neutrino bursts from the Galactic supernova and high energy cosmic neutrinos neutrino astrophysics will enter qualitatively new phase. Neutrinos and LHC (and future colliders), neutrino astronomy, neutrino structure of the Universe, and probably, neutrino technologies will be among leading topics of research.

Smirnov, Alexei Yu

2008-01-01T23:59:59.000Z

267

Report of the Solar and Atmospheric Neutrino Working Group  

E-Print Network (OSTI)

Solar Neutrino Experiments 3.1 Testing the Model of the Sun . . . . . . . . . . . . . . . . . . . . .propagate from solar center to surface, the Suns changingsolar neutrino projectusing neutrinos to understand the Sun.

2004-01-01T23:59:59.000Z

268

Experimental Requirements to Determine the Neutrino Mass Hierarchy Using Reactor Neutrinos  

E-Print Network (OSTI)

This paper presents experimental requirements to determine the neutrino mass hierarchy using reactor neutrinos. The detector shall be located at a baseline around 58 km from the reactor(s) to measure the energy spectrum of electron antineutrinos ($\\bar{\

Liang Zhan; Yifang Wang; Jun Cao; Liangjian Wen

2009-01-20T23:59:59.000Z

269

Measurement of the cosmic ray and neutrino-induced muon flux at the Sudbury neutrino observatory  

E-Print Network (OSTI)

Results are reported on the measurement of the atmospheric neutrino-induced muon flux at a depth of 2 kilometers below the Earths surface from 1229 days of operation of the Sudbury Neutrino Observatory (SNO). By measuring ...

Formaggio, Joseph A.

270

Search for muon neutrinos from Gamma-Ray Bursts with the IceCube neutrino telescope  

E-Print Network (OSTI)

the University of California. Search for muon neutrinos fromSearch for muon neutrinos from Gamma-Ray Bursts with theWe present the results of searches for high-energy muon

Abbasi, R.

2010-01-01T23:59:59.000Z

271

Blazing Cerenkov Flashes at the Horizons by Cosmic Rays and Neutrinos Induced Air-Showers  

E-Print Network (OSTI)

High Energy Cosmic Rays (C.R.) versus Neutrino and Neutralino induced Air-Shower maybe tested at Horizons by their muons, gamma and Cerenkov blazing signals. Inclined and Horizontal C.R. Showers (70-90 zenith angle) produce secondary (gamma, e+, e-) mostly suppressed by high column atmosphere depth. Earliest shower Cherenkov photons are diluted by large distances and by air opacity, while secondary penetrating muons and their successive decay into electrons and gamma, may revive additional Cerenkov lights. GeVs gamma telescopes at the top of the mountains or in Space may detect at horizons PeVs up to EeV C.R. and their secondaries. Details on arrival angle and column depth, shower shape, timing signature of photon flash intensity, may inform us on the altitude interaction and primary UHECR composition. Below the horizons, at zenith angle among copious single albedo muons, rare up-going showers traced by muon bundles would give evidence of rare tau Earth-Skimming neutrinos, at EeVs energies. Their rate may be comparable with 6.3 PeVs anti-neutrino electron induced air-shower (mostly hadronic) originated above and also below horizons, in interposed atmosphere by W resonance at Glashow peak. Additional and complementary UHE SUSY neutralinos at tens PeVs-EeV energy may blaze, by its characteristic electromagnetic signature. Their secondary shower blazing Cerenkov lights and distances might be disentangled from UHECR by Stereoscopic Telescopes such as Magic ones or Hess array experiment. The horizontal detection sensitivity of Magic in the present set up (if totally devoted to the Horizons Shower search) maybe already be comparable to AMANDA underground neutrino detector at PeVs energies.

D. Fargion

2004-12-21T23:59:59.000Z

272

Majorana neutrino mass matrices with three texture zeros and the sterile neutrino  

E-Print Network (OSTI)

As a consequence of the LSND anomaly and other hints of an eV scale sterile neutrino from particle physics and cosmology, the neutrino sector of the standard model of particle physics has to be extended and the smallest extension is the (3+1) model, i.e. three active neutrinos plus one sterile one. In this work we study the neutrino mass matrix $M_\

Yongchao Zhang

2013-01-30T23:59:59.000Z

273

Search for neutrinos from Gamma-Ray Bursts with the Baikal neutrino telescope NT200  

E-Print Network (OSTI)

We present an analysis of neutrinos detected with the Baikal neutrino telescope NT200 for correlations with gamma-ray bursts (GRB). No neutrino events correlated with GRB were observed. Assuming a Waxman-Bahcall spectrum, a neutrino flux upper limit of {\\bf $E^2 \\Phi Green's Function fluence limit for this search, which extends two orders of magnitude beyond the energy range of the Super-Kamiokande limit.

Avrorin, A

2009-01-01T23:59:59.000Z

274

If sterile neutrinos exist, how can one determine the total solar neutrino fluxes?  

E-Print Network (OSTI)

The 8B solar neutrino flux inferred from a global analysis of solar neutrino experiments is within 11% (1 sigma) of the predicted standard solar model value if only active neutrinos exist, but could be as large as 1.7 times the standard prediction if sterile neutrinos exist. We show that the total 8B neutrino flux (active plus sterile neutrinos) can be determined experimentally to about 10% (1 sigma) by combining charged current measurements made with the KamLAND reactor experiment and with the SNO CC solar neutrino experiment, provided the LMA neutrino oscillation solution is correct and the simulated performance of KamLAND is valid. Including also SNO NC data, the sterile component of the 8B neutrino flux can be measured by this method to an accuracy of about 12% (1 sigma) of the standard solar model flux. Combining Super-Kamiokande and KamLAND measurements and assuming the oscillations occur only among active neutrinos, the 8B neutrino flux can be measured to 6% (1 sigma); the total flux can be measured to an accuracy of about 9%. The total 7Be solar neutrino flux can be determined to an accuracy of about 28% (1 sigma) by combining measurements made with the KamLAND, SNO, and gallium neutrino experiments. One can determine the total 7Be neutrino flux to a one sigma accuracy of about 11% or better by comparing data from the KamLAND experiment and the BOREXINO solar neutrino experiment provided both detectors work as expected. The pp neutrino flux can be determined to about 15% using data from the gallium, KamLAND, BOREXINO, and SNO experiments.

John N. Bahcall; M. C. Gonzalez-Garcia; C. Pena-Garay

2002-04-16T23:59:59.000Z

275

Neutrino and Antineutrino Cross sections at MiniBooNE  

SciTech Connect

The MiniBooNE experiment has reported a number of high statistics neutrino and anti-neutrino cross sections -among which are the charged current quasi-elastic (CCQE) and neutral current elastic (NCE) neutrino scattering on mineral oil (CH2). Recently a study of the neutrino contamination of the anti-neutrino beam has concluded and the analysis of the anti-neutrino CCQE and NCE scattering is ongoing.

Dharmapalan, Ranjan; /Alabama U.

2011-10-01T23:59:59.000Z

276

Determination of alpha_s from tau decays  

E-Print Network (OSTI)

Hadronic tau decays offer the possibility of determining the strong coupling alpha_s at relatively low energy. Precisely for this reason, however, good control over the perturbative QCD corrections, the non-perturbative condensate contributions in the framework of the operator product expansion (OPE), as well as the corrections going beyond the OPE, the duality violations (DVs), is required. On the perturbative QCD side, the contour-improved versus fixed-order resummation of the series is still an issue, and will be discussed. Regarding the analysis, self-consistent fits to the data including all theory parameters have to be performed, and this is also explained in some detail. The fit quantities are moment integrals of the tau spectral function data in a certain energy window and care should be taken to have acceptable perturbative behaviour of those moments as well as control over higher-dimensional operator corrections in the OPE.

Jamin, Matthias

2013-01-01T23:59:59.000Z

277

Evidence for an excess of B -> D(*) Tau Nu decays  

E-Print Network (OSTI)

Based on the full BaBar data sample, we report improved measurements of the ratios R(D(*)) = B(B -> D(*) Tau Nu)/B(B -> D(*) l Nu), where l is either e or mu. These ratios are sensitive to new physics contributions in the form of a charged Higgs boson. We measure R(D) = 0.440 +- 0.058 +- 0.042 and R(D*) = 0.332 +- 0.024 +- 0.018, which exceed the Standard Model expectations by 2.0 sigma and 2.7 sigma, respectively. Taken together, our results disagree with these expectations at the 3.4 sigma level. This excess cannot be explained by a charged Higgs boson in the type II two-Higgs-doublet model. We also report the observation of the decay B -> D Tau Nu, with a significance of 6.8 sigma.

,

2012-01-01T23:59:59.000Z

278

Daya Bay Reactor Neutrino Project at NERSC  

NLE Websites -- All DOE Office Websites (Extended Search)

Daya Bay Reactor Neutrino Daya Bay Reactor Neutrino Experiment Daya Bay Reactor Neutrino Experiment Daya Bay is an international neutrino-oscillation experiment designed to determine the last unknown neutrino mixing angle θ13 using anti-neutrinos produced by the Daya Bay and Ling Ao Nuclear Power Plant reactors. The experiment is being built by blasting three kilometers of tunnel through the granite rock under the mountains where the power plants are located. Data collection is now scheduled to start in in 2011. On the PDSF cluster at NERSC, Daya Bay performs simulations of the detectors, reactors, and surrounding mountains to help design and anticipate detector properties and behavior. Once real data are available, Daya Bay will be using NERSC to analyze data and NERSC HPSS will be the central U.S. repository for all raw

279

Dynamical Collective Calculation of Supernova Neutrino Signals  

SciTech Connect

We present the first calculations with three flavors of collective and shock wave effects for neutrino propagation in core-collapse supernovae using hydrodynamical density profiles and the S matrix formalism. We explore the interplay between the neutrino-neutrino interaction and the effects of multiple resonances upon the time signal of positrons in supernova observatories. A specific signature is found for the inverted hierarchy and a large third neutrino mixing angle and we predict, in this case, a dearth of lower energy positrons in Cherenkov detectors midway through the neutrino signal and the simultaneous revelation of valuable information about the original fluxes. We show that this feature is also observable with current generation neutrino detectors at the level of several sigmas.

Gava, Jerome; Kneller, James; Volpe, Cristina; McLaughlin, G. C. [Institut de Physique Nucleaire, F-91406 Orsay cedex, CNRS/IN2P3 and University of Paris-XI (France); Department of Physics, North Carolina State University, Raleigh, North Carolina 27695-8202 (United States)

2009-08-14T23:59:59.000Z

280

Large Extra Dimensions, Sterile Neutrinos and Solar Neutrino Data  

Science Conference Proceedings (OSTI)

Solar, atmospheric, and LSND neutrino oscillation results require a light sterile neutrino, {nu}{sub B} , which can exist in the bulk of extra dimensions. Solar {nu}{sub e} , confined to the brane, can oscillate in the vacuum to the zero mode of {nu}{sub B} and via successive Mikheyev-Smirnov-Wolfenstein transitions to Kaluza-Klein states of {nu}{sub B} . This new way to fit solar data is provided by both low and intermediate string scale models. From average rates seen in the three types of solar experiments, the Super-Kamiokande spectrum is predicted with 73% probability, but dips characteristic of the 0.06 mm extra dimension should be seen in the SNO spectrum.

Caldwell, D. O.; Mohapatra, R. N.; Yellin, S. J.

2001-07-23T23:59:59.000Z

Note: This page contains sample records for the topic "tau neutrinos heavy" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

The Palo Verde Reactor Neutrino Experiment A Test for Long Baseline Neutrino Oscillations  

E-Print Network (OSTI)

:1. Our range of sensitivity is tuned to test the š¯ $ še solution of the atmospheric neutrino anomaly. 11 The Palo Verde Reactor Neutrino Experiment A Test for Long Baseline Neutrino Oscillations 94305 e Palo Verde Nuclear Generating Station,Tonopah AZ 85354 Our collaboration has installed a long

Piepke, Andreas G.

282

Exotic Solutions to the Solar Neutrino Problem and Some Implications for Low Energy Solar Neutrino Experiments  

E-Print Network (OSTI)

In this talk, I review, from the phenomenological point of view, solutions to the solar neutrino problem, which are not provided by the conventional neutrino oscillation induced by mass and flavor mixing, and show that they can provide a good fit to the observed data. I also consider some simple implications for low energy solar neutrino experiments.

H. Nunokawa

2001-05-03T23:59:59.000Z

283

Status of the Daya Bay Reactor Neutrino Oscillation Experiment  

E-Print Network (OSTI)

Status of the Daya Bay Reactor Neutrino OscillationCheng-Ju Lin The Daya Bay reactor neutrino experiment [1] isneutrinos from the nuclear reactors at different baselines.

Lin, Cheng-Ju Stephen

2011-01-01T23:59:59.000Z

284

Status of the Daya Bay Reactor Neutrino Oscillation Experiment  

E-Print Network (OSTI)

neutrinos from the nuclear reactors at different baselines.will be commissioned Nuclear Reactor Anti-neutrino detectorthe nuclear power complex has two pairs of reactor cores (

Lin, Cheng-Ju Stephen

2011-01-01T23:59:59.000Z

285

Measuring neutrino oscillation parameters using $\  

SciTech Connect

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 ({Delta}m{sub atm}{sup 2} and sin{sup 2} 2{theta}{sub atm}). The oscillation signal consists of an energy-dependent deficit of {nu}{sub {mu}} 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 {nu}{sub {mu}}-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 {nu}{sub {mu}}-disappearance analysis, incorporating this new estimator were: {Delta}m{sup 2} = 2.32{sub -0.08}{sup +0.12} x 10{sup -3} eV{sup 2}, sin {sup 2} 2{theta} > 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 {nu}}{sub {mu}} beam, yielded somewhat different best-fit parameters {Delta}{bar m}{sup 2} = (3.36{sub -0.40}{sup +0.46}(stat.) {+-} 0.06(syst.)) x 10{sup -3}eV{sup 2}, sin{sup 2} 2{bar {theta}} = 0.86{sub -0.12}{sup _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.

Backhouse, Christopher James; /Oxford U.

2011-02-01T23:59:59.000Z

286

Pion condensation in a dense neutrino gas  

E-Print Network (OSTI)

We argue that using an equilibrated gas of neutrinos it is possible to probe the phase diagram of QCD for finite isospin and small baryon chemical potentials. We discuss this region of the phase diagram in detail and demonstrate that for large enough neutrino densities a Bose-Einstein condensate of positively charged pions arises. Moreover, we show that for nonzero neutrino density the degeneracy in the lifetimes and masses of the charged pions is lifted.

Hiroaki Abuki; Tomas Brauner; Harmen J. Warringa

2009-01-16T23:59:59.000Z

287

Nuclear correction factors from neutrino DIS  

E-Print Network (OSTI)

Neutrino Deep Inelastic Scattering on nuclei is an essential process to constrain the strange quark parton distribution functions in the proton. The critical component on the way to using the neutrino DIS data in a proton PDF analysis is understanding the nuclear effects in parton distribution functions. We parametrize these effects by nuclear parton distribution functions and we use this framework to analyze the consistency of neutrino DIS data with other nuclear data.

K. Kovarik

2011-07-15T23:59:59.000Z

288

Nuclear correction factors from neutrino DIS  

E-Print Network (OSTI)

Neutrino Deep Inelastic Scattering on nuclei is an essential process to constrain the strange quark parton distribution functions in the proton. The critical component on the way to using the neutrino DIS data in a proton PDF analysis is understanding the nuclear effects in parton distribution functions. We parametrize these effects by nuclear parton distribution functions and we use this framework to analyze the consistency of neutrino DIS data with other nuclear data.

Kovarik, K

2011-01-01T23:59:59.000Z

289

Neutrino Factory Designs and R&D  

E-Print Network (OSTI)

European, Japanese, and US Neutrino Factory designs are presented. The main R&D issues, and the associated R&D programs, are discussed.

S. Geer

2002-07-15T23:59:59.000Z

290

Search for Neutrinos from the Sun  

DOE R&D Accomplishments (OSTI)

A solar neutrino detection system has been built to observe the neutrino radiation from the sun. The detector uses 3,900,000 liters of tetrachloroethylene as the neutrino capturing medium. Argon is removed from the liquid by sweeping with helium gas, and counted in a small low level proportional counter. The recovery efficiency of the system was tested with Ar{sup 36} by the isotope dilution method, and also with Ar{sup 37} produced in the liquid by fast neutrons. These tests demonstrate that Ar{sup 37} produced in the liquid by neutrino capture can be removed with a 95 percent efficiency by the procedure used.

Davis, Raymond Jr.

1968-09-00T23:59:59.000Z

291

Boron abundance and solar neutrino spectrum distortion  

E-Print Network (OSTI)

The presence of neutrinos from Boron decay in the flux observed on Earth is attested by the observation of their energy spectrum. Possible distortions of the spectrum investigated in current detectors are often interpreted in terms of evidence in favour or against various schemes of neutrino oscillations. We stress here that a distortion of the spectrum at high energies could also result from an increase in the ratio of neutrinos originating from ($^3$He+p) and $^8$B reactions. While a $^8$B neutrino depletion would contribute to this effect, an increase in the Hep contribution seems also needed to reproduce the preliminary data.

R. Escribano; J. -M. Frere; A. Gevaert; D. Monderen

1998-05-06T23:59:59.000Z

292

Review of Solar and Reactor Neutrinos  

E-Print Network (OSTI)

Over the last several years, experiments have conclusively demonstrated that neutrinos are massive and that they mix. There is now direct evidence for $\

A. W. P. Poon

2005-09-19T23:59:59.000Z

293

Gamma Ray Burst Neutrinos Probing Quantum Gravity  

E-Print Network (OSTI)

Very high energy, short wavelength, neutrinos may interact with the space-time foam predicted by theories of quantum gravity. They would propagate like light through a crystal lattice and be delayed, with the delay depending on the energy. This will appear to the observer as a violation of Lorenz invariance. Back of the envelope calculations imply that observations of neutrinos produced by gamma ray bursts may reach Planck-scale sensitivity. We revisit the problem considering two essential complications: the imprecise timing of the neutrinos associated with their poorly understood production mechanism in the source and the indirect nature of their energy measurement made by high energy neutrino telescopes.

M. C. Gonzalez-Garcia; F. Halzen

2006-11-28T23:59:59.000Z

294

Majorana Neutrino Masses from Flavor Symmetries  

E-Print Network (OSTI)

In this talk we discuss the implications of the Minimal Supersymmetric Standard Model augmented by a single U(1) anomalous family symmetry for neutrino masses and mixing angles. The left-handed neutrino states are provided with Majorana masses through a dimension-five operator in the absence of right handed neutrino components. Assuming symmetric lepton mass matrices, the model predicts inverse hierarchical neutrino mass spectrum, theta_13=0 and large mixing while at the same time it provides acceptable mass matrices for the charged fermions.

A. Psallidas

2005-05-11T23:59:59.000Z

295

Neutrino Factory Physics Study: Two Day Meeting  

NLE Websites -- All DOE Office Websites (Extended Search)

Two-Day Meeting The Fermilab Directorate has requested a 6 month study to assess the physics capabilities of neutrino factories as a function of their energies, intensities,...

296

Neutrino Physics at a Muon Collider  

NLE Websites -- All DOE Office Websites (Extended Search)

Physics at a Muon Collider The intense muon beams needed for high luminosity muon colliders produce intense beams of neutrinos. Dedicated muon storage rings with long straight...

297

Collective Neutrino Flavor Transformation In Supernovae  

E-Print Network (OSTI)

We examine coherent active-active channel neutrino flavor evolution in environments where neutrino-neutrino forward scattering can engender large-scale collective flavor transformation. We point out a key quantity, the "total effective energy", which is conserved in several important regimes. Using this concept, we analyze collective neutrino and antineutrino flavor oscillation in the "synchronized" mode and what we term the "bi-polar" mode. We thereby are able to explain why large collective flavor mixing can develop on short timescales even when vacuum mixing angles are small in, e.g., a dense gas of initially pure $\

Huaiyu Duan; George M. Fuller; Yong-Zhong Qian

2005-11-09T23:59:59.000Z

298

3.8 The Missing Solar Neutrinos  

NLE Websites -- All DOE Office Websites (Extended Search)

phenomenon was first suggested by observations at the oldest solar neutrino detector (in South Dakota), for which Raymond Davis of Brookhaven National Laboratory won the 2000 Wolf...

299

The ANTARES underwater neutrino telescope  

E-Print Network (OSTI)

ANTARES is the first undersea neutrino telescope. It is in its complete configuration since May 2008 at about 2.5 km below the sea surface close to Marseille. Data from 12 lines are being analyzed and are producing first results. Here we discuss first analysis results for 5 lines and 10 lines, and we also comment on the performance of the full detector. We show that the detector has capabilities for discriminating upgoing neutrino events from the much larger amount of downgoing atmospheric muons and that data and simulation are in good agreement. We then discuss the physics reach of the detector for what concerns point-like source and dark matter searches.

Teresa Montaruli; for the ANTARES Collaboration

2008-10-21T23:59:59.000Z

300

Neutrino Mass and Flavour Models  

E-Print Network (OSTI)

We survey some of the recent promising developments in the search for the theory behind neutrino mass and tri-bimaximal mixing, and indeed all fermion masses and mixing. We focus in particular on models with discrete family symmetry and unification, and show how such models can also solve the SUSY flavour and CP problems. We also discuss the theoretical implications of the measurement of a non-zero reactor angle, as hinted at by recent experimental measurements.

King, Stephen F

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "tau neutrinos heavy" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Neutrino Mass and Flavour Models  

E-Print Network (OSTI)

We survey some of the recent promising developments in the search for the theory behind neutrino mass and tri-bimaximal mixing, and indeed all fermion masses and mixing. We focus in particular on models with discrete family symmetry and unification, and show how such models can also solve the SUSY flavour and CP problems. We also discuss the theoretical implications of the measurement of a non-zero reactor angle, as hinted at by recent experimental measurements.

Stephen F King

2009-09-16T23:59:59.000Z

302

Graphene, neutrino mass and oscillation  

E-Print Network (OSTI)

A resolution of the Abraham-Minkowski dilemma is presented that other constant velocities can play the role of c in the theory of relativity. For example, in 2005 electrons of graphene were discovered to behave as if the coefficient is a Fermi velocity. Then we propose a conjecture for neutrinos to avoid the contradiction among two-component theory, negative rest mass-square and oscillation.

Z. Y. Wang

2009-09-10T23:59:59.000Z

303

Higgs boson decay into heavy quarks and heavy leptons: higher order corrections  

E-Print Network (OSTI)

Theoretical predictions for the decay width of Standard Model Higgs boson into bottom quarks and tau-leptons, in the case when M_HHiggs boson into bb and tau+tau- are discussed.

Kim, Victor T

2010-01-01T23:59:59.000Z

304

The Solar Neutrino Problem - An Update  

E-Print Network (OSTI)

The $^8$B solar neutrino flux as measured by Super-Kamiokande is consistent with the $^{37}$Ar production rate in $^{37}$Cl at Homestake. GALLEX and SAGE, continue to observe $^{71}$Ge production rates in $^{71}$Ga that are consistent with the minimal signal expected from the solar luminosity. The observed $^8$B solar neutrino flux is in good agreement with that predicted by the standard solar model of Dar and Shaviv with nuclear reaction rates that are supported by recent measurements of nuclear fusion cross sections at low energies. The measurements of Super-Kamiokande, SAGE and GALLEX suggest that the expected the pep, $^7$Be and NO solar neutrino fluxes are strongly suppressed. This can be explained by neutrino oscillations and the Mikheyev-Smirnov-Wolfenstein effect. Since neither a flavor change, nor a terrestrial variation, nor a spectral distortion of the $^8$B solar neutrino flux has been observed yet, the solar neutrino problem does not provide conclusive evidence for neutrino properties beyond the standard electroweak model. The deviations of the experimental results from those predicted by the standard solar models may reflect the approximate nature of of solar models and of our knowledge of nuclear reaction rates, radiation transport and particle diffusion in dense stellar plasmas. Only future observations of spectral distortions, or terrestrial modulation or flavor change of solar neutrinos in solar neutrino experiments, such as Super-Kamiokande, SNO, Borexino and HELLAZ will be able to establish that neutrino properties beyond the minimal standard electroweak model are responsible for the solar neutrino problem.

Arnon Dar; Giora Shaviv

1998-08-11T23:59:59.000Z

305

Long Baseline Neutrino Beams and Large Detectors  

SciTech Connect

It is amazing to acknowledge that in roughly 70 years from when the existence of the neutrino was postulated, we are now contemplating investigating the mysteries of this particle (or particles) requiring and utilizing detectors of 300 ktons , distances of 1,000-2,000 kilometers, beam intensities of megawatts and underground depth of 5,000 feet. This evolution has evolved slowly, from the experimental discovery of the neutrino in 1956, to the demonstration that there were two neutrinos in 1962 and three and only three by 1991. The great excitement occurred in the 2000's coming from the study of solar and atmospheric neutrinos in which neutrinos were observed to oscillate and therefore have mass. Although the absolute mass of any of the neutrinos has yet to be determined (the upper limit is less than I electron volt) the difference in this square of these masses has been measured, yielding a value of (2.3 {+-} .2) 10{sup -3} ev{sup 2} for atmospheric neutrinos and (7.6 {+-} .2) 10{sup -5} ev{sup 2} for solar neutrinos. In addition their mixing angles were found to be 45{sup o} for atmospheric neutrinos and 34{sup o} for solar neutrinos. This present state of knowledge on neutrinos is pictorially displayed in Fig. 1. Of course, mixing between flavors had already been observed in the quark sector as exemplified by the Cabbibo-Kobayashi-Meskawa Matrix. It was therefore natural to extend this formalism to the lepton sector involving unitary 3 x 3 matrices and one CP violating phase. This is shown in Fig. 2 for the two sectors, quark and leptons including the Jarlskog invariant (J).

Samios,N.P.

2008-10-27T23:59:59.000Z

306

Applying Bayesian Neural Networks to Separate Neutrino Events from Backgrounds in Reactor Neutrino Experiments  

E-Print Network (OSTI)

A toy detector has been designed to simulate central detectors in reactor neutrino experiments in the paper. The samples of neutrino events and three major backgrounds from the Monte-Carlo simulation of the toy detector are generated in the signal region. The Bayesian Neural Networks(BNN) are applied to separate neutrino events from backgrounds in reactor neutrino experiments. As a result, the most neutrino events and uncorrelated background events in the signal region can be identified with BNN, and the part events each of the fast neutron and $^{8}$He/$^{9}$Li backgrounds in the signal region can be identified with BNN. Then, the signal to noise ratio in the signal region is enhanced with BNN. The neutrino discrimination increases with the increase of the neutrino rate in the training sample. However, the background discriminations decrease with the decrease of the background rate in the training sample.

Ye Xu; Yixiong Meng; Weiwei Xu

2008-08-02T23:59:59.000Z

307

Extremely High Energy Neutrinos, Neutrino Hot Dark Matter, and the Highest Energy Cosmic Rays  

E-Print Network (OSTI)

Extremely high energy (up to 10**(22) eV) cosmic neutrino beams initiate high energy particle cascades in the background of relic neutrinos from the Big Bang. We perform numerical calculations to show that such cascades could contribute more than 10% to the observed cosmic ray flux above 10**(19) eV if neutrinos have masses in the electron volt range. The required intensity of primary neutrinos could be consistent with astrophysical models for their production if the maximum neutrino energy reaches to 10**(22) eV and the massive neutrino dark matter is locally clustered. Future observations of ultra high energy cosmic rays will lead to an indirect but practical search for neutrino dark matter.

Shigeru Yoshida; Guenter Sigl; Sangjin Lee

1998-08-14T23:59:59.000Z

308

Performance of the ATLAS tau trigger with 7 TeV collision data at the LHC  

E-Print Network (OSTI)

Tau leptons are a fundamental ingredient in the discovery of new physics at the LHC. The reconstruction of hadronic tau decays at the trigger level, although a very challenging task in proton-proton collision environments, allows us to double the sample of tau decays collected, and provides additional discovery power to final states which include tau leptons. In this contribution we show the understanding of the tau trigger system using data collected with the ATLAS detector at the LHC in proton-proton collisions at a center-of-mass energy of 7 TeV. We present the most relevant quantities used in the different stages of the trigger selection, and the trigger efficiencies as a function of ET using tau-like QCD events passing the offline reconstruction and identification selection.

Robinson, M; The ATLAS collaboration

2010-01-01T23:59:59.000Z

309

Jack Steinberger and the Muon-Neutrino  

Office of Scientific and Technical Information (OSTI)

Jack Steinberger and the Muon-Neutrino Resources with Additional Information Jack Steinberger Photograph by Harry Sticker, courtesy AIP Emilio Segre Visual Archives, Physics Today Collection In an interview, Jack Steinberger spoke about his 1988 Nobel Prize winning research. He states "I did an experiment, together with several other people at Brookhaven National Laboratory ... which showed that there is a second kind of neutrino. The neutrino has elementary particles. Elementary particles exist in families of particles ... . At the time, the elementary particles which were involved were the electrons and the neutrino. ... [W]e required the [BNL] accelerator, which was the effort of very many people, ... and this allowed [us] to make a beam of these neutrinos, and we were able to convince ourselves that these neutrinos were not the same kind of neutrinos as those which had been seen before. They were associated with not electrons, but with something called [muons]. So we were able to understand that there is a different neutrino associated with the [muon] than with the electron.

310

Why Are Neutrinos Light? -- An Alternative  

SciTech Connect

We review the recent proposal that neutrinos are light because their masses are proportional to a low scale, f, of lepton flavor symmetry breaking. This mechanism is testable because the resulting pseudo-Goldstone bosons, of mass m_G, couple strongly with the neutrinos, affecting the acoustic oscillations during the eV era of the early universe that generate the peaks in the CMB radiation. Characteristic signals result over a very wide range of (f, m_G) because of a change in the total relativistic energy density and because the neutrinos scatter rather than free-stream. Thermodynamics allows a precise calculation of the signal, so that observations would not only confirm the late-time neutrino mass mechanism, but could also determine whether the neutrino spectrum is degenerate, inverted or hierarchical and whether the neutrinos are Dirac or Majorana. The flavor symmetries could also give light sterile states. If the masses of the sterile neutrinos turn on after the MeV era, the LSND oscillations can be explained without upsetting big bang nucleosynthesis, and, since the sterile states decay to lighter neutrinos and pseudo-Goldstones, without giving too much hot dark matter.

Hall, Lawrence J.; Oliver, Steven J.

2004-09-23T23:59:59.000Z

311

Consistency of 8B neutrino spectra  

E-Print Network (OSTI)

We identify and quantify systematic effects not accounted for in two previous measurements of the alpha-alpha relative-energy distribution in the beta decay of 8B, which can explain the apparent disagreement with respect to two newer measurements. This settles a current dispute concerning the shape of the 8B neutrino spectrum of importance to solar-neutrino studies.

Oliver S. Kirsebom; Hans O. U. Fynbo; Riccardo Raabe; Karsten Riisager; Thomas Roger

2012-11-15T23:59:59.000Z

312

Variations in the Solar Neutrino Flux  

DOE R&D Accomplishments (OSTI)

Observations are reported from the chlorine solar neutrino detector in the Homestake Gold Mine, South Dakota, USA. They extend from 1970 to 1985 and yield an average neutrino capture rate of 2.1 +- 0.3 SNU. The results from 1977 to 1985 show an anti-correlation with the solar activity cycle, and an apparent increased rate during large solar flares.

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

1987-08-02T23:59:59.000Z

313

Big World of Small Neutrinos Hitoshi Murayama  

E-Print Network (OSTI)

· Finally discovered by Cowan and Reines using a nuclear reactor in 1958 · Massless Neutrinos, Phys. Rev. 48, 391 (1935) Bohr: At the present stage of atomic theory, however, we may say that we have Colloquium 11 Anti-Neutrinos are Right-handed · CPT theorem in quantum field theory ­ C: interchange

Murayama, Hitoshi

314

Neutrino Balls and Gamma-Ray Bursts  

E-Print Network (OSTI)

We propose a mechanism by which the neutrino emission from a supernova-type explosion can be converted into a gamma-ray burst of total energy $\\sim 10^{50}$ ergs. This occurs naturally if the explosion is situated inside a ball of trapped neutrinos, which in turn may lie at a galactic core. There are possible unique signatures of this scenario.

B. Holdom; R. A. Malaney

1993-06-17T23:59:59.000Z

315

A measurement of the branching fraction B(tau$^{+}$ --> h$^{-}$ $\\pi$sup(0) $\  

E-Print Network (OSTI)

Using data from the CLEO II detector at CESR, we measure {\\cal B}(\\tau^\\pm\\rightarrow h^\\pm\\pi^0\

Artuso, M; He, D; Horwitz, N; Kennett, R; Mountain, R; Moneti, G C; Muheim, F; Mukhin, Y; Playfer, S; Rozen, Y; Stone, S; Thulasidas, M; Vasseur, G; Xing, X; Zhu, G; Bartelt, J; Csorna, S E; Egyed, Z; Jain, V; Kinoshita, K; Barish, B; Chadha, M; Chan, S; Cowen, D F; Eigen, G; Miller, J S; O'Grady, C; Urheim, J; Weinstein, A J; Acosta, D; Athanas, M; Masek, G; Paar, H P; Sivertz, M; Gronberg, J; Kutschke, R; Menary, S; Morrison, R J; Nakanishi, S; Nelson, H N; Nelson, T K; Qiao, C; Richman, J D; Ryd, A; Tajima, H; Sperka, D; Witherell, M S; Procario, M; Balest, R; Cho, K; Daoudi, M; Ford, W T; Johnson, D R; Lingel, K; Lohner, M; Rankin, P; Smith, J G; Alexander, J P; Bebek, C; Berkelman, K; Bloom, K; Browder, T E; Cassel, D G; Cho, H A; Coffman, D M; Crowcroft, D S; Drell, P S; Ehrlich, R; Gaidarev, P; Galik, R S; Garca-Sciveres, M; Geiser, B; Gittelman, B; Gray, S W; Hartill, D L; Heltsley, B K; Jones, C D; Jones, S L; Kandaswamy, J; Katayama, N; Kim, P C; Kreinick, D L; Ludwig, G S; Masui, J; Mevissen, J; Mistry, N B; Ng, C R; Nordberg, E; Patterson, J R; Peterson, D; Riley, D; Salman, S; Sapper, M; Wrthwein, F; Avery, P; Freyberger, A; Rodrguez, J; Stephens, R; Yang, S; Yelton, J; Cinabro, D; Henderson, S; Liu, T; Saulnier, M; Wilson, R; Yamamoto, H; Bergfeld, T; Eisenstein, B I; Gollin, G; Ong, B; Palmer, M; Selen, M; Thaler, J J; Edwards, K W; Ogg, M; Spaan, B; Bellerive, A; Britton, D I; Hyatt, E R F; MacFarlane, D B; Patel, P M; Sadoff, A J; Ammar, R; Ball, S; Baringer, P; Bean, A; Besson, D; Coppage, D; Copty, N; Davis, R; Hancock, N; Kelly, M; Kotov, S; Kravchenko, I; Kwak, N; Lam, H; Kubota, Y; Lattery, M; Momayezi, M; Nelson, J K; Patton, S; Perticone, D; Poling, R; Savinov, V; Schrenk, S; Wang, R; Alam, M S; Kim, I J; Nemati, B; O'Neill, J J; Severini, H; Sun, C R; Zoeller, M M; Crawford, G; Daubenmier, C M; Fulton, R; Fujino, D; Gan, K K; Honscheid, K; Kagan, H; Kass, R; Lee, J; Malchow, R; Skovpen, Y; Sung, M; White, C; Butler, F; Fu, X; Kalbfleisch, G; Ross, W R; Skubic, P L; Wood, M; Fast, J; McIlwain, R L; Miao, T; Miller, D H; Modesitt, M; Payne, D; Shibata, E I; Shipsey, I P J; Wang, P N; Battle, M; Ernst, J; Gibbons, L; Kwon, Y; Roberts, S; Thorndike, E H; Wang, C H; Dominick, J; Lambrecht, M; Sanghera, S; Shelkov, V; Skwarnicki, T; Stroynowski, R; Volobuev, I P; Wei, G; Zadorozhny, P

1994-01-01T23:59:59.000Z

316

Form invariance and symmetry in the neutrino mass matrix  

SciTech Connect

We present the general form of the unitary matrices keeping invariant the Majorana neutrino mass matrix of specific texture suitable for explaining oscillation data. In the case of the tri-bimaximal pattern with two degenerate masses, we give a specific realization of the underlying U(1) symmetry which can be uplifted to a symmetry in a complete theory including charged leptons. For this, we present a model with three light SM-like Higgs doublets and one heavy Higgs triplet and find that one can accommodate the hierarchy of the charged-lepton masses. The lepton mass spectrum can also be achieved in another model extending the SM with three SM-singlet scalars transforming nontrivially under the flavor symmetry. We discuss how such a model has room for generating enough baryon asymmetry through leptogenesis in the framework of type-I and -II seesaw mechanisms.

Lashin, E. I. [Department of Physics and Astronomy, College of Science, King Saud University, Riyadh (Saudi Arabia); Ain Shams University, Faculty of Science, Cairo 11566 (Egypt); Nasri, S.; Malkawi, E. [Department of Physics, UAE University, P.O. Box 17551, Al-Ain (United Arab Emirates); Chamoun, N. [Physics Department, HIAST, P.O. Box 31983, Damascus (Syrian Arab Republic)

2011-01-01T23:59:59.000Z

317

Neutrino background flux from sources of ultrahigh-energy cosmic-ray nuclei  

Science Conference Proceedings (OSTI)

Motivated by Pierre Auger Observatory results favoring a heavy nuclear composition for ultrahigh-energy (UHE) cosmic rays, we investigate implications for the cumulative neutrino background. The requirement that nuclei not be photodisintegrated constrains their interactions in sources, therefore limiting neutrino production via photomeson interactions. Assuming a dN{sub CR}/dE{sub CR{proportional_to}}E{sub CR}{sup -2} injection spectrum and photodisintegration via the giant dipole resonance, the background flux of neutrinos is lower than E{sub {nu}}{sup 2{Phi}}{sub {nu}{approx}1}0{sup -9} GeV cm{sup -2} s{sup -1} sr{sup -1} if UHE nuclei ubiquitously survive in their sources. This is smaller than the analogous Waxman-Bahcall flux for UHE protons by about 1 order of magnitude and is below the projected IceCube sensitivity. If IceCube detects a neutrino background, it could be due to other sources, e.g., hadronuclear interactions of lower-energy cosmic rays; if it does not, this supports our strong restrictions on the properties of sources of UHE nuclei.

Murase, Kohta [Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto, 606-8502 (Japan); CCAPP, Ohio State University, Columbus, Ohio 43210 (United States); Beacom, John F. [CCAPP, Ohio State University, Columbus, Ohio 43210 (United States); Department of Physics, Ohio State University, Columbus, Ohio 43210 (United States); Department of Astronomy, Ohio State University, Columbus, Ohio 43210 (United States)

2010-06-15T23:59:59.000Z

318

Resolving Standard and Nonstandard CP Violation Phases in Neutrino Oscillations  

SciTech Connect

Neutrino oscillations can exhibit extra CP violation effects, beyond those expected from the standard Kobayashi-Maskawa phase delta, if non-standard neutrino interactions are at play. We show that it is possible to disentangle the two CP violating effects by measuring muon neutrino appearance using a near-far two detector setting in a neutrino factory experiment.

Gago, A. M. [Seccion Fisica, Departamento de Ciencias, Pontificia Universidad Catolica del Peru, Apartado 1761, Lima (Peru); Minakata, H.; Uchinami, S. [Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397 (Japan); Nunokawa, H. [Departamento de Fisica, Pontificia Universidade Catolica do Rio de Janeiro, C. P. 38071, 22452-970, Rio de Janeiro (Brazil); Zukanovich Funchal, R. [Instituto de Fisica, Universidade de Sao Paulo, C. P. 66.318, 05315-970 Sao Paulo (Brazil)

2010-03-30T23:59:59.000Z

319

Solar neutrino measurements in Super-Kamiokande-I  

E-Print Network (OSTI)

The details of Super--Kamiokande--I's solar neutrino analysis are given. Solar neutrino measurement in Super--Kamiokande is a high statistics collection of $^8$B solar neutrinos via neutrino-electron scattering. The analysis method and results of the 1496 day data sample are presented. The final oscillation results for the data are also presented.

Super-Kamiokande Collaboration

2005-08-27T23:59:59.000Z

320

Opportunities for Neutrino Physics at the Spallation Neutron Source (SNS)  

E-Print Network (OSTI)

In this paper we discuss opportunities for a neutrino program at the Spallation Neutrons Source (SNS) being commissioning at ORNL. Possible investigations can include study of neutrino-nuclear cross sections in the energy rage important for supernova dynamics and neutrino nucleosynthesis, search for neutrino-nucleus coherent scattering, and various tests of the standard model of electro-weak interactions.

Yu Efremenko; W R Hix

2008-07-17T23:59:59.000Z

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321

Overview of the LBNE Neutrino Beam  

Science Conference Proceedings (OSTI)

The Long Baseline Neutrino Experiment (LBNE) will utilize a neutrino beamline facility located at Fermilab. The facility is designed to aim a beam of neutrinos toward a detector placed at the Deep Underground Science and Engineering Laboratory (DUSEL) in South Dakota. The neutrinos are produced in a three-step process. First, protons from the Main Injector hit a solid target and produce mesons. Then, the charged mesons are focused by a set of focusing horns into the decay pipe, towards the far detector. Finally, the mesons that enter the decay pipe decay into neutrinos. The parameters of the facility were determined by an amalgam of the physics goals, the Monte Carlo modeling of the facility, and the experience gained by operating the NuMI facility at Fermilab. The initial beam power is expected to be {approx}700 kW, however some of the parameters were chosen to be able to deal with a beam power of 2.3 MW.

Moore, C.D.; He, Yun; Hurh, Patrick; Hylen, James; Lundberg, Byron; McGee, Mike; Misek, Joel; Mokhov, Nikolai V.; Papadimitriou, Vaia; Plunkett, Rob; Schultz, Ryan; /Fermilab

2011-03-22T23:59:59.000Z

322

Noncommutative Theory in Light of Neutrino Oscillation  

E-Print Network (OSTI)

Solar neutrino problem and atmospheric neutrino anomaly which are both long-standing issues studied intensively by physicists in the past several decades, are reckoned to be able to be solved simultaneously in the framework of the assumption of the neutrino oscillation. For the presence of the Lorentz invariance in the Standard Model, the massless neutrino can't have flavor mixing and oscillation. However, we exploit the q-deformed noncommutative theory to derive a general modified dispersion relation, which implies some violation of the Lorentz invariance. Then it is found that the application of the q-deformed dispersion relation to the neutrino oscillation can provide a sound explanation for the current data from the reactor and long baseline experiments.

Shao-Xia Chen; Zhao-Yu Yang

2003-12-07T23:59:59.000Z

323

Solar neutrinos and the solar composition problem  

E-Print Network (OSTI)

Standard solar models (SSM) are facing nowadays a new puzzle: the solar composition problem. New determinations of solar metal abundances lead SSM calculations to conflict with helioseismological measurements, showing discrepancies that extend from the convection zone to the solar core and can not be easily assigned to deficiencies in the modelling of the solar convection zone. We present updated solar neutrino fluxes and uncertainties for two SSM with high (old) and low (new) solar metallicity determinations. The uncertainties in iron and carbon abundances are the largest contribution to the uncertainties of the solar neutrino fluxes. The uncertainty on the ^14N+p -> ^15O+g rate is the largest of the non-composition uncertainties to the CNO neutrino fluxes. We propose an independent method to help identify which SSM is the correct one. Present neutrino data can not distinguish the solar neutrino predictions of both models but ongoing measurements can help to solve the puzzle.

Carlos Pena-Garay; Aldo Serenelli

2008-11-16T23:59:59.000Z

324

Unified Graphical Summary of Neutrino Mixing Parameters  

E-Print Network (OSTI)

The neutrino mixing parameters are presented in a number of different ways by the various experiments, e.g. SuperKamiokande, K2K, SNO, KamLAND and Chooz and also by the Particle Data Group. In this paper, we argue that presenting the data in terms of $\\sin^2 \\theta$, where $\\theta$ is the mixing angle appropriate for a given experiment has a direct physical interpretation. For current atmospheric, solar and reactor neutrino experiments, the $\\sin^2 \\theta$'s are effectively the probability of finding a given flavor in a particular neutrino mass eigenstate. The given flavor and particular mass eigenstate varies from experiment to experiment, however, the use of $\\sin^2 \\theta$ provides a unified picture of all the data. Using this unified picture we present a graphical way to represent these neutrino mixing parameters which includes the uncertainties. All of this is performed in the context of the present experimental status of three neutrino oscillations.

Olga Mena; Stephen Parke

2003-12-10T23:59:59.000Z

325

A search for sterile neutrinos in MINOS  

SciTech Connect

MINOS, the Main Injector Neutrino Oscillation Search, is a long baseline neutrino oscillation experiment based at Fermilab National Accelerator Laboratory. The experiment uses a 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 attain a very high precision for parameters in the atmospheric sector of neutrino oscillations. In addition to precisely determining {Delta}m{sub 23}{sup 2} and {theta}{sub 23} through the disappearance of {nu}{sub {mu}}, MINOS is able to measure {nu}{sub {mu}} {yields} {nu}{sub sterile} by looking for a deficit in the number of neutral current interactions seen in the Far detector. In this thesis, we present the results of a search for sterile neutrinos in MINOS.

Osiecki, Thomas Henry; /Texas U.

2007-12-01T23:59:59.000Z

326

Solar neutrinos and the solar composition problem  

E-Print Network (OSTI)

Standard solar models (SSM) are facing nowadays a new puzzle: the solar composition problem. New determinations of solar metal abundances lead SSM calculations to conflict with helioseismological measurements, showing discrepancies that extend from the convection zone to the solar core and can not be easily assigned to deficiencies in the modelling of the solar convection zone. We present updated solar neutrino fluxes and uncertainties for two SSM with high (old) and low (new) solar metallicity determinations. The uncertainties in iron and carbon abundances are the largest contribution to the uncertainties of the solar neutrino fluxes. The uncertainty on the ^14N+p -> ^15O+g rate is the largest of the non-composition uncertainties to the CNO neutrino fluxes. We propose an independent method to help identify which SSM is the correct one. Present neutrino data can not distinguish the solar neutrino predictions of both models but ongoing measurements can help to solve the puzzle.

Pena-Garay, Carlos

2008-01-01T23:59:59.000Z

327

Neutrino astronomy with the MACRO detector  

E-Print Network (OSTI)

High energy gamma ray astronomy is now a well established field and several sources have been discovered in the region from a few GeV up to several TeV. If sources involving hadronic processes exist, the production of photons would be accompanied by neutrinos too. Other possible neutrino sources could be related to the annihilation of WIMPs at the center of galaxies with black holes. We present the results of a search for point-like sources using 1100 upward-going muons produced by neutrino interactions in the rock below and inside the MACRO detector in the underground Gran Sasso Laboratory. These data show no evidence for a possible neutrino point-like source or for possible correlations between gamma ray bursts and neutrinos. They have been used to set flux upper limits for candidate point-like sources which are in the range 10^-14-10^-15 cm-2 s-1.

M. Ambrosio

2000-02-26T23:59:59.000Z

328

RELIABILITY CONSIDERATIONS OF ELECTRONICS COMPONENTS FOR THE DEEP UNDERWATER MUON AND NEUTRINO DETECTION SYSTEM  

E-Print Network (OSTI)

Considerations for the Dtep Underwater Muon and NeutrinoPresented at the Deep Underwater Huon and Neutrino DetectionCOMPONENTS FOR THE DEEP UNDERWATER MUON AND NEUTRINO

Leskovar, B.

2010-01-01T23:59:59.000Z

329

Asymmetry and cross-section in e sup + e sup minus yields. tau. sup +. tau. sup minus from radical s = 52 to 57 GeV  

SciTech Connect

The reaction e{sup {plus}}e{sup {minus}} {yields} {tau}{sup {plus}}{tau}- was studied at center-of-mass energies of 52, 55, 56, and 57 GeV in the AMY detector, located on the TRISTAN storage ring at KEK, Japan. Creation of {tau}-lepton pairs in e{sup {plus}}e{sup {minus}} collisions is an excellent test of the Standard Model. The forward-backward asymmetry is a particularly sensitive test, since the measurement depends not only on the number of events, but also on the distribution of these events. Measurements of the total production cross-section, {sigma}{sub {tau}{tau}}, and the differential cross-section, d{sigma}{sub {tau}}/d{Omega}, were made using data contained in a total integrated luminosity of 17.65 pb{sup {minus}1}. Total measured cross sections at each energy were in agreement with predictions from the Standard Model. The forward-backward asymmetry in the polar production angle, A{sub fb}, was obtained from the differential cross-section. At the average energy of {radical}s {equals} 55.16 GeV, it was determined that A{sub fb} {equals} {minus}0.33 {plus minus} 0.09. This is in good agreement with the Standard Model prediction of A{sub fb (Std. Mod.)} {equals} {minus}0.30 at this energy. Values of the weak coupling constants, g{sub V}{sup {tau}}g{sub V}{sup e} and g{sub A}{sup {tau}}g{sub A}{sup e}, were extracted from the measured asymmetry with the results g{sub V}{sup {tau}}g{sub V}{sup e} {equals} {minus}0.12 {plus minus} 0.08 and g{sub A}{sup {tau}}g{sub A}{sup e} {equals} 0.28 {plus minus} 0.08, in agreement with the Standard Model values of g{sub V}{sup {tau}}g{sub V}{sup e} (Std. Mod.) {equals} 0.0016 and g{sub A}{sup {tau}}g{sub A}{sup e} (Std. Mod.) 0.25. Lower limits on the QED cutoff parameters, {Lambda}{plus minus}, were obtained from the measured cross-section.

Malchow, R.L.

1989-01-01T23:59:59.000Z

330

Detection of the Neutrino Fluxes from Several Sources  

E-Print Network (OSTI)

It is considered the detection of neutrinos moving from the opposite directions. The states of the particle of the detector interacting with the neutrinos are connected with the P-transformation. Hence only a half of neutrinos gives contribution into the superposition of the neutrino states. Taking into account the effect of the opposite neutrino directions the total neutrino flux from several sources are in the range 0.5--1 of that without the effect. The neutrino flux from nuclear reactors measured in the KamLAND experiment is $0.611\\pm 0.085 {\\rm (stat)} \\pm 0.041 {\\rm (syst)} $ of the expected flux. Calculations for the conditions of the KamLAND experiment yield the neutrino flux taking into account the effect of the opposite neutrino directions, 0.555, of that without the effect that may account for the neutrino flux observed in the KamLAND experiment.

D. L. Khokhlov

2003-02-19T23:59:59.000Z

331

SAGE: Solar Neutrino Data from SAGE, the Russian-American Gallium Solar Neutrino Experiment  

DOE Data Explorer (OSTI)

SAGE is a solar neutrino experiment based on the reaction 71Ga + n goes to 71Ge + e-. The 71Ge atoms are chemically extracted from a 50-metric ton target of Ga metal and concentrated in a sample of germane gas mixed with xenon. The atoms are then individually counted by observing their decay back to 71Ga in a small proportional counter. The distinguishing feature of the experiment is its ability to detect the low-energy neutrinos from proton-proton fusion. These neutrinos, which are made in the primary reaction that provides the Sun's energy, are the major component of the solar neutrino flux and have not been observed in any other way. To shield the experiment from cosmic rays, it is located deep underground in a specially built facility at the Baksan Neutrino Observatory in the northern Caucasus mountains of Russia. Nearly 100 measurements of the solar neutrino flux have been made during 1990-2000, and their combined result is a neutrino capture rate that is well below the prediction of the Standard Solar Model. The significant suppression of the solar neutrino flux that SAGE and other solar neutrino experiments have observed gives a strong indication for the existence of neutrino oscillations. [copied from the SAGE homepage at http://ewi.npl.washington.edu/SAGE/SAGE.html

SAGE Collaboration

332

A road map to solar neutrino fluxes, neutrino oscillation parameters, and tests for new physics  

E-Print Network (OSTI)

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 1.02 +- 0.02 (1 sigma) times the flux predicted by the BP00 standard solar model; the 7Be neutrino flux is 0.93^{+0.25}_{-0.63} the predicted flux; and the ^8B flux is 1.01 +- 0.04 the predicted flux. The neutrino oscillation parameters are: Delta m^2 = 7.3^{+0.4}_{-0.6}\\times 10^{-5} eV^2 and tan^2 theta_{12} = 0.41 +- 0.04. 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 at low energies. A future 7Be nu-e scattering experiment accurate to +- 10 % can reduce the uncertainty in the experimentally determined 7Be neutrino flux by a factor of four and the uncertainty in the p-p neutrino flux by a factor of 2.5 (to +- 0.8 %). A future p-p experiment must be accurate to better than +- 3 % to shrink the uncertainty in tan^2 theta_{12} by more than 15 %. The idea that the Sun shines because of nuclear fusion reactions can be tested accurately by comparing the observed photon luminosity of the Sun with the luminosity inferred from measurements of solar neutrino fluxes. Based upon quantitative analyses of present and simulated future experiments, we answer the question: Why perform low-energy solar neutrino experiments?

John N. Bahcall; Carlos Pena-Garay

2003-05-15T23:59:59.000Z

333

Discrete symmetries and neutrino masses  

SciTech Connect

We constructed a model of neutrino masses using Froggatt-Nielsen mechanism with U(1)xZ{sub 3}xZ{sub 2} flavor symmetry. The model predicts that (2/3)m{sub 2}/m{sub 3}{approx}{radical}(2)sin{theta}{sub 13} at lepton number violating scale M{sub 1}. It is shown that the small values for m{sub 2}/m{sub 3} and sin{theta}{sub 13} are consequences of breaking discrete symmetries.

Siyeon, Kim [Department of Physics, Chung-Ang University, Seoul 156-756 (Korea, Republic of)

2005-02-01T23:59:59.000Z

334

Particle Data Group - 2012 Particle Listings  

NLE Websites -- All DOE Office Websites (Extended Search)

Cut-off date for this update was January 15, 2012. Cut-off date for this update was January 15, 2012. GAUGE AND HIGGS BOSONS (gamma, g, W, Z, ...) gamma g (gluon) graviton W boson Z boson Higgs Bosons (H0 and H+-), Searches for Heavy Bosons, Other Than Higgs Bosons, Searches for (rev.) Axions (A0) and Other Very Light Bosons, Searches for (rev.) Collapse Gauge and Higgs Boson table LEPTONS (e, mu, tau, neutrinos, heavy leptons ...) electron muon tau Heavy Charged Lepton Searches Introduction to the Neutrino Properties Listings (rev.) Neutrino Properties Number of Neutrino Types Double-beta Decay Note on Neutrinoless Double-beta Decay (rev.) Introduction to Three-Neutrino Mixing Parameters Listings Neutrino Mixing (rev.) Heavy Neutral Leptons, Searches for Collapse Leptons table QUARKS (u, d, s, c, b, t, ...) Note on the Quark Masses (rev.)

335

Particle Data Group - 2008 Particle Listings  

NLE Websites -- All DOE Office Websites (Extended Search)

GAUGE AND HIGGS BOSONS (gamma, g, W, Z, ...) gamma g (gluon) graviton W boson Z boson Higgs Bosons (H0 and H+-), Searches for Heavy Bosons, Other Than Higgs Bosons, Searches for Axions (A0) and Other Very Light Bosons, Searches for Collapse Gauge and Higgs Boson table LEPTONS (e, mu, tau, neutrinos, heavy leptons ...) electron muon tau Heavy Charged Lepton Searches Introduction to the Neutrino Properties Listings Neutrino Properties Number of Neutrino Types Double-beta Decay Note on Neutrinoless Double-beta Decay Neutrino Mixing Solar Neutrinos Review Heavy Neutral Leptons, Searches for Collapse Leptons table QUARKS (u, d, s, c, b, t, ...) Note on the Quark Masses LIGHT QUARKS --- u, d, s c quark b quark t quark b' quark (4**th Generation) t' quark (4**th Generation) Free Quark Searches

336

Particle Data Group - 2013 Particle Listings  

NLE Websites -- All DOE Office Websites (Extended Search)

. . and 2013 partial update for the 2014 edition. Cut-off date for this update was January 15, 2013. GAUGE AND HIGGS BOSONS (gamma, g, W, Z, ...) gamma g (gluon) graviton W boson Z boson Higgs Bosons (H0 and H+-) Heavy Bosons, Other Than Higgs Bosons, Searches for (rev.) Axions (A0) and Other Very Light Bosons, Searches for (rev.) Collapse Gauge and Higgs Boson table LEPTONS (e, mu, tau, neutrinos, heavy leptons ...) electron muon tau Heavy Charged Lepton Searches Introduction to the Neutrino Properties Listings (rev.) Neutrino Properties Number of Neutrino Types Double-beta Decay Note on Neutrinoless Double-beta Decay (rev.) Introduction to Three-Neutrino Mixing Parameters Listings Neutrino Mixing (rev.) Heavy Neutral Leptons, Searches for Collapse Leptons table QUARKS (u, d, s, c, b, t, ...)

337

Particle Data Group - 2010 Particle Listings  

NLE Websites -- All DOE Office Websites (Extended Search)

GAUGE AND HIGGS BOSONS (gamma, g, W, Z, ...) gamma g (gluon) graviton W boson Z boson Higgs Bosons (H0 and H+-), Searches for Heavy Bosons, Other Than Higgs Bosons, Searches for Axions (A0) and Other Very Light Bosons, Searches for Collapse Gauge and Higgs Boson table LEPTONS (e, mu, tau, neutrinos, heavy leptons ...) electron muon tau Heavy Charged Lepton Searches Introduction to the Neutrino Properties Listings Neutrino Properties Number of Neutrino Types Double-beta Decay Note on Neutrinoless Double-beta Decay Introduction to Three-Neutrino Mixing Parameters Listings Neutrino Mixing Heavy Neutral Leptons, Searches for Collapse Leptons table QUARKS (u, d, s, c, b, t, ...) Note on the Quark Masses LIGHT QUARKS --- u, d, s c quark b quark t quark b' quark (4**th Generation)

338

Search for Higgs bosons decaying to tau(+)tau(-) pairs in p(p)over-bar collisions at root s=1.96 TeV  

Science Conference Proceedings (OSTI)

We present a search for the production of neutral Higgs bosons decaying into {tau}{sup +}{tau}{sup -} pairs in p{bar p} collisions at a center-of-mass energy of 1.96 TeV. The data, corresponding to an integrated luminosity of 5.4 fb{sup -1}, were collected by the D0 experiment at the Fermilab Tevatron Collider. We set upper limits at the 95% C.L. on the product of production cross section and branching ratio for a scalar resonance decaying into {tau}{sup +}{tau}{sup -} pairs, and we interpret these limits as limits on the production of Higgs bosons in the minimal supersymmetric standard model (MSSM) and as constraints in the MSSM parameter space.

Abazov, V.M.; Abazov, V. M.; Abbott, B.; Achary, B. S.; Adams, M.; Adams, T.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Alverson, G.; Alves, G. A.; Aoki, M.; Arov, M.; Askew, A.; Asman, B.; Atramentov, O.; Avila, C.; BackusMayes, J.; Badaud, F.; Bagby, L.; Baldin, B.; Bandurin, D. V.; Banerjee, S.; Barberis, E.; Baringer, P.; Barreto, J.; Bartlett, J. F.; Bassler, U.; Bazterra, V.; Beale, S.; Bean, A.; Begalli, M.; Begel, M.; Belanger-Champagne, C.; Bellantoni, L.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Bertram, I.; Besancon, M.; Beuselinck, R.; Bezzubov, V. A.; Bhat, P. C.; Bhatnagar, V.; Blazey, G.; Blessing, S.; Bloom, K.; Boehnlein, A.; Boline, D.; Boos, E. E.; Borissov, G.; Bose, T.; Brandt, A.; Brandt, O.; Brock, R.; Brooijmans, G.; Bross, A.; Brown, D.; Brown, J.; Bu, X. B.; Buehler, M.; Buescher, V.; Bunichev, V.; Burdin, S.; Burnett, T. H.; Buszello, C. P.; Calpas, B.; Camacho-Perez, E.; Carrasco-Lizarraga, M. A.; Casey, B. C. K.; Castilla-Valdez, H.; Chakrabarti, S.; Chakraborty, D.; Chan, K. M.; Chandra, A.; Chen, G.; Chevalier-Thery, S.; Cho, D. K.; Cho, S. W.; Choi, S.; Choudhary, B.; Cihangir, S.; Claes, D.; Clutter, J.; Cooke, M.; Cooper, W. E.; Corcoran, M.; Couderc, F.; Cousinou, M. -C.; Croc, A.; Cutts, D.; Das, A.; Davies, G.; De, K.; de Jong, S. J.; De La Cruz-Burelo, E.; Deliot, F.; Demarteau, M.; Demina, R.; Denisov, D.; Denisov, S. P.; Desai, S.; Deterre, C.; DeVaughan, K.; Diehl, H. T.; Diesburg, M.; Ding, P. F.; Dominguez, A.; Dorland, T.; Dubey, A.; Dudko, L. V.; Duggan, D.; Duperrin, A.; Dutt, S.; Dyshkant, A.; Eads, M.; Edmunds, D.; Ellison, J.; Elvira, V. D.; Enari, Y.; Evans, H.; Evdokimov, A.; Evdokimov, V. N.; Facini, G.; Ferbel, T.; Fiedler, F.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Fortner, M.; Fox, H.; Fuess, S.; Garcia-Bellido, A.; Gavrilov, V.; Gay, P.; Geng, W.; Gerbaudo, D.; Gerber, C. E.; Gershtein, Y.; Ginther, G.; Golovanov, G.; Goussiou, A.; Grannis, P. D.; Greder, S.; Greenlee, H.; Greenwood, Z. D.; Gregores, E. M.; Grenier, G.; Gris, Ph.; Grivaz, J. -F.; Grohsjea, A.; Gruenendahl, S.; Gruenewald, M. W.; Guillemin, T.; Guo, F.; Gutierrez, G.; Gutierrez, P.; Haas, A.; Hagopia, S.; Haley, J.; Hang, L.; Harder, K.; Harein, A.; Hauptman, J. M.; Hays, J.; Head, T.; Hebbeker, T.; Hedin, D.; Hegab, H.; Heinson, A. P.; Heintz, U.; Hensel, C.; Heredia-De La Cruz, I.; Herner, K.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hoangau, T.; Hobbs, J. D.; Hoeneisen, B.; Hohlfeld, M.; Hubacek, Z.; Huske, N.; Hynek, V.; Lashvili, I.; Ilchenko, Y.; Illingworth, R.; Ito, A. S.; Jabeen, S.; Jaffre, M.; Jamin, D.; Jayasinghe, A.; Jesik, R.; Johns, K.; Johnson, M.; Johnston, D.; Jonckheere, A.; Jonsson, P.; Joshi, J.; Jung, A. W.; Juste, A.; Kaadze, K.; Kajfasz, E.; Karmanov, D.; Kasper, P. A.; Katsanos, I. I.; Kehoe, R.; Kermiche, S.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y. N.; Kirby, M. H.; Kohli, J. M.; Kozelov, A. V.; Kraus, J.; Kulikov, S.; Kumar, A.; Kupco, A.; Kurca, T.; Kuzmin, V. A.; Kvita, J.; Lammers, S.; Landsberg, G.; Lebrun, P.; Lee, H. S.; Lee, S. W.; Lee, W. M.; Lellouch, J.; Li, L.; Li, Q. Z.; Lietti, S. M.; Lim, J. K.; Lincoln, D.; Linnemann, J.; Lipaev, V. V.; Lipton, R.; Liu, Y.; Liu, Z.; Lobodenko, A.; Lokajicek, M.; de Sa, R. Lopes; Lubatti, H. J.; Luna-Garcia, R.; Lyon, A. L.; Maciel, A. K. A.; Mackin, D.; Madar, R.; Magana-Villalba, R.; Malik, S.; Malyshev, V. L.; Maravin, Y.; Martinez-Ortega, J.; McCarthy, R.; McGivern, C. L.; Meijer, M. M.; Melnitchouk, A.; Menezes, D.; Mercadante, P. G.; Merkin, M.; Meyer, A.; Meyer, J.; et al.

2012-02-01T23:59:59.000Z

339

Measuring Active-Sterile Neutrino Oscillations with a Stopped Pion Neutrino Source  

E-Print Network (OSTI)

The question of the existence of light sterile neutrinos is of great interest in many areas of particle physics, astrophysics, and cosmology. Furthermore, should the MiniBooNE experiment at Fermilab confirm the LSND oscillation signal, then new measurements are required to identify the mechanism responsible for these oscillations. Possibilities include sterile neutrinos, CP or CPT violation, variable mass neutrinos, Lorentz violation, and extra dimensions. In this paper, we consider an experiment at a stopped pion neutrino source to determine if active-sterile neutrino oscillations with delta-m greater than 0.1 eV2 can account for the signal. By exploiting stopped pi+ decay to produce a monoenergetic nu_mu source, and measuring the rate of the neutral current reaction nu_x + 12C -> nu_x +12C* as a function of distance from the source, we show that a convincing test for active-sterile neutrino oscillations can be performed.

G. T. Garvey; A. Green; C. Green; W. C. Louis; G. B. Mills; G. McGregor; H. Ray; R. Schirato; R. G. Van de Water; D. H. White

2005-01-03T23:59:59.000Z

340

The SNO Solar Neutrino Data, Neutrinoless Double Beta-Decay and Neutrino Mass Spectrum  

E-Print Network (OSTI)

Assuming 3 neutrino mixing and massive Majorana neutrinos, we analyze the implications of the results of the solar neutrino experiments, including the latest SNO data, which favor the LMA MSW solution of the solar neutrino problem with \\tan^2 \\theta_sol | in neutrinoless double beta decay. For \\cos (2 \\theta_sol) \\geq 0.26, which follows from the analysis of the new solar neutrino data, we find significant lower limits on || in the cases of quasi-degenerate and inverted hierarchy neutrino mass spectrum, || \\geq 0.035 eV and || \\geq 8.5 10^-3 eV, respectively. If the spectrum is hierarchical the upper limit holds || \\leq 8.2 10^-3 eV. Correspondingly, not only a measured value of || \

S. Pascoli; S. T. Petcov

2002-05-02T23:59:59.000Z

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341

Solving the Solar Neutrino Problem 2 km Underground -- the Sudbury Neutrino Observatory  

E-Print Network (OSTI)

The Sudbury Neutrino Observatory (SNO) is capable of measuring simultaneously the flux of electron-type neutrinos and the total flux of all active flavours of neutrinos originating from the Sun. A model-independent test of neutrino flavour transformation was performed by comparing these two measurements. Assuming an undistorted neutrino energy spectrum, this transformation has been definitively demonstrated in the pure D2O phase of the SNO experiment. In the second phase with dissolved NaCl in the D2O, the total active solar neutrino flux was measured without any assumption on the energy dependence of flavour transformation. In this talk, results from these measurements, their physics implications and the current status of the SNO experiment are presented.

A. W. P. Poon; for the SNO Collaboration

2003-11-30T23:59:59.000Z

342

Solar neutrinos: beyond standard solar models  

E-Print Network (OSTI)

After a short survey of the physics of solar neutrinos, giving an overview of hydrogen burning reactions, predictions of standard solar models and results of solar neutrino experiments, we discuss the solar-model-independent indications in favour of non-standard neutrino properties. The experimental results look to be in contradiction with each other, even disregarding some experiment: unless electron neutrinos disappear in their trip from the sun to the earth, the fluxes of intermediate energy neutrinos (those from 7Be electron capture and from the CNO cycle) result to be unphysically negative, or anyway extremely reduced with respect to standard solar model predictions. Next we review extensively non-standard solar models built as attempts to solve the solar neutrino puzzle. The dependence of the central solar temperature on chemical composition, opacity, age and on the values of the astrophysical S-factors for hydrogen-burning reactions is carefully investigated. Also, possible modifications of the branching among the various pp-chains in view of nuclear physics uncertainties are examined. Assuming standard neutrinos, all solar models examined fail in reconciling theory with experiments, even when the physical and chemical inputs are radically changed with respect to present knowledge and even if some of the experimental results are discarded.

V. Castellani; S. Degl'Innocenti; G. Fiorentini; M. Lissia; B. Ricci

1996-06-30T23:59:59.000Z

343

The status of the solar neutrino problem  

Science Conference Proceedings (OSTI)

Perhaps the most outstanding discrepancy between prediction and measurements in current particle physics comes from the solar neutrino problem, in which a large deficit of high-energy solar neutrinos is observed. Many Nonstandard Solar Models have been invoked to try to reduce the predicted flux, but all have run into problems in trying to reproduce other measured parameters (e.g., the luminosity) of the Sun. Other explanations involving new physics such as neutrino decay and neutrino oscillations, etc. have also been proffered. Again, most of these explanations have been ruled out by either laboratory or astrophysical measurements. It appears that perhaps the most likely particle physics solution is that of matter enhanced neutrino oscillation, the Mikheyev-Smirnov-Wolfenstein (MSW) oscillations. Two new radiochemical gallium experiments, which have a low enough threshold to be sensitive to the dominant flux of low-energy p-p neutrinos, now also report a deficit and also favor a particle physics solution. The next generation of solar experiments promise to finally resolve the source of the ``solar neutrino problem`` by the end of this decade.

Bowles, T.J.

1993-12-01T23:59:59.000Z

344

Improving the estimation of Kendall's tau when censoring affects only one of the variables  

Science Conference Proceedings (OSTI)

This paper considers the estimation of Kendall's tau for bivariate data (X,Y) when only Y is subject to right-censoring. Although @t is estimable under weak regularity conditions, the estimators proposed by Brown et al. [1974. Nonparametric tests of ... Keywords: Censoring, Conditional distribution, Copula, Covariate, Generalized Kaplan-Meier estimator, Kendall's tau, Lifetime data

David Beaudoin; Thierry Duchesne; Christian Genest

2007-08-01T23:59:59.000Z

345

Search for the Baryon and Lepton Number Violating Decays tau to Lambda h  

SciTech Connect

The authors have searched for the violation of baryon number B and lepton number L in the (B-L)-conserving modes {tau}{sup -} {yields} {bar {Lambda}}{sup 0}{pi}{sup -} and {tau}{sup -} {yields} {bar {Lambda}}{sup 0}K{sup -} as well as the (B-L)-violating modes {tau}{sup -} {yields} {Lambda}{sup 0}{pi}{sup -} and {tau}{sup -} {yields} {Lambda}{sup 0}K{sup -} using 237 fb{sup -1} of data collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} storage ring. They do not observe any signal and determine preliminary upper limits on the branching fractions {Beta}({tau}{sup -} {yields} {bar {Lambda}}{sup 0}{pi}{sup -}) < 5.9 x 10{sup -8}, {Beta}({tau}{sup -} {yields} {Lambda}{sup 0}{pi}{sup -}) < 5.8 x 10{sup -8}, {Beta}({tau}{sup -} {yields} {bar {Lambda}}{sup 0}K{sup -}) < 7.2 x 10{sup -8}, and {Beta}({tau}{sup -} {yields} {Lambda}{sup 0}K{sup -}) < 15 x 10{sup -8} at 90% confidence level.

Aubert, B.

2006-11-28T23:59:59.000Z

346

Neutrino chirality flip in a supernova and the bound on the neutrino magnetic moment  

E-Print Network (OSTI)

The neutrino chirality-flip process under the conditions of the supernova core is investigated in detail with the plasma polarization effects in the photon propagator taken into account. It is shown that the contribution of the proton fraction of plasma is essential. New upper bounds on the neutrino magnetic moment are obtained: mu_nu flip. The best astrophysical upper bound on the neutrino magnetic moment is improved by the factor of 3 to 7.

A. V. Kuznetsov; N. V. Mikheev

2006-06-25T23:59:59.000Z

347

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

Science Conference Proceedings (OSTI)

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 {Delta}m{sub 23}{sup 2} = (2.32{sub -0.08}{sup +0.12}) x 10{sup -3} eV{sup 2}/c{sup 4} and the mixing angle sin{sup 2}(2{theta}{sub 32}) > 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 7.2{sigma} and the neutrino quantum decoherence hypothesis is disfavored at 9.0{sigma}.

Coleman, Stephen James; /William-Mary Coll.

2011-01-01T23:59:59.000Z

348

Scalar neutrinos at the LHC  

Science Conference Proceedings (OSTI)

We study a softly broken supersymmetric model whose gauge symmetry is that of the standard model gauge group times an extra Abelian symmetry U(1){sup '}. We call this gauge-extended model the U(1){sup '} model, and we study a U(1){sup '} model with a secluded sector such that neutrinos acquire Dirac masses via higher-dimensional terms allowed by the U(1){sup '} invariance. In this model the {mu} term of the minimal supersymmetric model (MSSM) is dynamically induced by the vacuum expectation value of a singlet scalar. In addition, the model contains exotic particles necessary for anomaly cancellation, and extra singlet bosons for achieving correct Z{sup '}/Z mass hierarchy. The neutrinos are charged under U(1){sup '}, and thus, their production and decay channels differ from those in the MSSM in strength and topology. We implement the model into standard packages and perform a detailed analysis of sneutrino production and decay at the Large Hadron Collider, for various mass scenarios, concentrating on three types of signals: (1) 0l+MET, (2) 2l+MET, and (3) 4l+MET. We compare the results with those of the MSSM whenever possible, and analyze the standard model background for each signal. The sneutrino production and decays provide clear signatures enabling distinction of the U(1){sup '} model from the MSSM at the LHC.

Demir, Durmus A. [Department of Physics, Izmir Institute of Technology, IZTECH, TR35430 Izmir, Turkey, (Turkey); Frank, Mariana [Department of Physics, Concordia University, 7141 Sherbrooke St. West, Montreal, Quebec, Canada H4B 1R6, (Canada); Selbuz, Levent [Department of Physics, Izmir Institute of Technology, IZTECH, TR35430 Izmir, Turkey, (Turkey); Department of Engineering Physics, Ankara University, TR06100 Ankara (Turkey); Turan, Ismail [Ottawa-Carleton Institute of Physics, Carleton University, 1125 Colonel By Drive Ottawa, Ontario, K1S 5B6 (Canada)

2011-05-01T23:59:59.000Z

349

Measuring Neutrino Oscillations with Nuclear Reactors  

SciTech Connect

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 crucial information on 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.

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

2007-10-26T23:59:59.000Z

350

Dirac Neutrino Masses from Generalized Supersymmetry Breaking  

SciTech Connect

We demonstrate that Dirac neutrino masses in the experimentally preferred range are generated within supersymmetric gauge extensions of the standard model with a generalized supersymmetry breaking sector. If the superpotential neutrino Yukawa terms are forbidden by the gauge symmetry [such as a U(1){sup '}], sub-eV scale effective Dirac mass terms can arise at tree level from hard supersymmetry breaking Yukawa couplings, or at one loop due to nonanalytic soft supersymmetry breaking trilinear scalar couplings. The radiative neutrino magnetic and electric dipole moments vanish at one-loop order.

Demir, Durmus A.; Everett, Lisa L.; Langacker, Paul [Department of Physics, Izmir Institute of Technology, IZTECH, TR35430 Izmir (Turkey); Deutsches Elektronen-Synchrotron, DESY, D-22603 Hamburg (Germany); Department of Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States); School of Natural Sciences, Institute for Advanced Study, Einstein Drive, Princeton, New Jersey 08540 (United States)

2008-03-07T23:59:59.000Z

351

Neutrino Capture Reactions on $^{40}$Ar  

E-Print Network (OSTI)

Gamow-Teller (GT) strength in $^{40}$Ar is studied by shell-model calculations with monopole-based universal intearction, which has tensor components of $\\pi$\\rho$-meson exchanges. Calculated GT strength is found to be consistent with the experimental data obtained by recent ($p, n$) reactions. Neutrino capture cross sections on $^{40}$Ar for solar neutrinos from $^{8}$B are found to be enhanced compared with previous calculations. The reaction cross sections for multipoles other than $0^{+}$ and $1^{+}$ are obtained by random-phase approximation (RPA). Their contributions become important for neutrino energies larger than 50 MeV.

Toshio Suzuki; Michio Honma

2012-11-17T23:59:59.000Z

352

Neutrino-Accelerated Hot Hydrogen Burning  

E-Print Network (OSTI)

We examine the effects of significant electron anti-neutrino fluxes on hydrogen burning. Specifically, we find that the bottleneck weak nuclear reactions in the traditional pp-chain and the hot CNO cycle can be accelerated by anti-neutrino capture, increasing the energy generation rate. We also discuss how anti-neutrino capture reactions can alter the conditions for break out into the rp-process. We speculate on the impact of these considerations for the evolution and dynamics of collapsing very- and super- massive compact objects.

Chad T. Kishimoto; George M. Fuller

2006-06-23T23:59:59.000Z

353

NEUTRINO SPECTRA FROM ACCRETION DISKS: NEUTRINO GENERAL RELATIVISTIC EFFECTS AND THE CONSEQUENCES FOR NUCLEOSYNTHESIS  

Science Conference Proceedings (OSTI)

Black hole (BH) accretion disks have been proposed as good candidates for a range of interesting nucleosynthesis, including the r-process. The presence of the BH influences the neutrino fluxes and affects the nucleosynthesis resulting from the interaction of the emitted neutrinos and hot outflowing material ejected from the disk. We study the impact of general relativistic effects on the neutrinos emitted from BH accretion disks. We present abundances obtained by considering null geodesics and energy shifts for two different disk models. We find that both the bending of the neutrino trajectories and the energy shifts have important consequences for the nucleosynthetic outcome.

Caballero, O. L.; McLaughlin, G. C. [Department of Physics, North Carolina State University, Raleigh, NC 27695 (United States); Surman, R., E-mail: lcaballe@uw.edu, E-mail: olcaball@ncsu.edu, E-mail: gail_mclaughlin@ncsu.edu, E-mail: surmanr@union.edu [Department of Physics and Astronomy, Union College, Schenectady, NY 12308 (United States)

2012-02-01T23:59:59.000Z

354

Neutrino Spectra from Accretion Disks: Neutrino General Relativistic Effects and the Consequences for Nucleosynthesis  

E-Print Network (OSTI)

Black hole accretion disks have been proposed as good candidates for a range of interesting nucleosynthesis, including the r-process. The presence of the black hole influences the neutrino fluxes and affects the nucleosynthesis resulting from the interaction of the emitted neutrinos and hot outflowing material ejected from the disk. We study the impact of general relativistic effects on the neutrinos emitted from black hole accretion disks. We present abundances obtained by considering null geodesics and energy shifts for two different disk models. We find that both the bending of the neutrino trajectories and the energy shifts have important consequences for the nucleosynthetic outcome

O. L Caballero; G. C. McLaughlin; R. Surman

2011-05-31T23:59:59.000Z

355

Measurement of the nue and Total 8B Solar Neutrino Fluxes with theSudbury Neutrino Observatory Phase I Data Set  

SciTech Connect

This article provides the complete description of resultsfrom the Phase I data set of the Sudbury Neutrino Observatory (SNO). ThePhase I data set is based on a 0.65 kt-year exposure of heavy water tothe solar 8B neutrino flux. Included here are details of the SNO physicsand detector model, evaluations of systematic uncertainties, andestimates of backgrounds. Also discussed are SNO's approach tostatistical extraction of the signals from the three neutrino reactions(charged current, neutral current, and elastic scattering) and theresults of a search for a day-night asymmetry in the ?e flux. Under theassumption that the 8B spectrum is undistorted, the measurements fromthis phase yield a solar ?e flux of ?(?e) =1.76+0.05?0.05(stat.)+0.09?0.09 (syst.) x 106 cm?2 s?1, and a non-?ecomponent ?(? mu) = 3.41+0.45?0.45(stat.)+0.48?0.45 (syst.) x 106 cm?2s?1. The sum of these components provides a total flux in excellentagreement with the predictions of Standard Solar Models. The day-nightasymmetry in the ?e flux is found to be Ae = 7.0 +- 4.9 (stat.)+1.3?1.2percent (sys.), when the asymmetry in the total flux is constrained to bezero.

Aharmim, B.; Ahmad, Q.R.; Ahmed, S.N.; Allen, R.C.; Andersen,T.C.; Anglin, J.D.; Buehler, G.; Barton, J.C.; Beier, E.W.; Bercovitch,M.; Bergevin, 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.; Burritt, T.H.; Cameron, J.; Chan, Y.D.; Chen, H.H.; Chen, M.; Chen, X.; Cleveland, B.T.; Cowan, J.H.M.; Cowen, D.F.; Cox, G.A.; Currat, C.A.; Dai, X.; Dalnoki-Veress, F.; Davidson, W.F.; Deng, H.; DiMarco, M.; 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.; Fleurot, F.; Ford, R.J.; Formaggio, J.A.; Fowler, M.M.; Frame, K.; Frank, E.D.; Frati, W.; Gagnon,N.; Germani, J.V.; Gil, S.; Goldschmidt, A.; Goon, J.T.M.; Graham, K.; Grant, D.R.; Guillian, E.; 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.; Henning, R.; Hepburn, J.D.; Heron, H.; Hewett, J.; Hime,A.; Howard, C.; Howe, M.A.; Huang, M.; Hykawy, J.G.; Isaac, M.C.P.; Jagam, P.; Jamieson, B.; Jelley, N.A.; Jillings, C.; Jonkmans, G.; Kazkaz, K.; Keener, P.T.; Kirch, K.; Klein, J.R.; Knox, A.B.; Komar,R.J.; Kormos, L.L.; Kos, M.; Kouzes, R.; Krueger, A.; Kraus, C.; Krauss,C.B.; Kutter, T.; Kyba, C.C.M.; Labranche, H.; Lange, R.; Law, J.; Lawson, I.T.; Lay, M.; Lee, H.W.; Lesko, K.T.; Leslie, J.R.; Levine, I.; Loach, J.C.; Locke, W.; Luoma, S.; Lyon, J.; MacLellan, R.; Majerus, S.; Mak, H.B.; Maneira, J.; Marino, A.D.; Martin, R.; McCauley, N.; McDonald,A.B.; McDonald, D.S.; McFarlane, K.; McGee, S.; McGregor, G.; MeijerDrees, R.; Mes, H.; Mifflin, C.; Miknaitis, K.K.S.; Miller, M.L.; Milton,G.; Moffat, B.A.; Monreal, B.; Moorhead, M.; Morrissette, B.; Nally,C.W.; Neubauer, M.S.; et al.

2007-02-01T23:59:59.000Z

356

A Measurement of Neutrino Charged Current Interactions and a Search for Muon Neutrino Disappearance with the Fermilab Booster Neutrino Beam  

SciTech Connect

In this thesis, we report on a measurement of muon neutrino inclusive charged current interactions on carbon in the few GeV region, using the Fermilab Booster Neutrino Beam. The all neutrino mode data collected in the SciBooNE experiment is used for this analysis. We collected high-statistics CC interaction sample at SciBooNE, and extracted energy dependent inclusive charged current interaction rates and cross sections for a wide energy range from 0.25 GeV to {approx}3 GeV. We measure the interaction rates with 6-15% precision, and the cross sections with 10-30% precision. We also made an energy integrated measurements, with the precisions of 3% for the rate, and 8% for the cross section measurements. This is the first measurement of the CC inclusive cross section on carbon around 1 GeV. This inclusive interaction measurement is nearly free from effects of hadron re-interactions in the nucleus. Hence, it is complementary to other exclusive cross section measurements, and essential to understand the neutrino interaction cross sections in the few GeV region, which is relevant to ongoing and future neutrino oscillation experiments. This analysis also provides the normalization for SciBooNE's previous cross section ratio measurements for charged current coherent pion production and neutral current neutral pion production. Then, a precise comparison between our previous measurements and the model predictions becomes possible. The result of the interaction rate measurement is used to constrain the product of the neutrino flux and the cross section at the other experiment on the Fermilab Booster Neutrino Beam: Mini-BooNE. We conducted a search for short-baseline muon neutrino disappearance using data both from SciBooNE and MiniBooNE, to test a possible neutrino oscillation with sterile neutrinos which is suggested by the LSND experiment. With this constraint by SciBooNE, we significantly reduced the flux and the cross section uncertainties at MiniBooNE, and achieved the world best sensitivity for the {nu}{sub {mu}} disappearance at 0.5 < {Delta}m{sup 2} < 30 (eV{sup 2}). We found no significant oscillation signal, and set one of the world strongest limits for the sterile neutrino models.

Nakajima, Yasuhiro; /Kyoto U.

2011-01-01T23:59:59.000Z

357

A Measurement of Neutrino Charged Current Interactions and a Search for Muon Neutrino Disappearance with the Fermilab Booster Neutrino Beam  

SciTech Connect

In this thesis, we report on a measurement of muon neutrino inclusive charged current interactions on carbon in the few GeV region, using the Fermilab Booster Neutrino Beam. The all neutrino mode data collected in the SciBooNE experiment is used for this analysis. We collected high-statistics CC interaction sample at SciBooNE, and extracted energy dependent inclusive charged current interaction rates and cross sections for a wide energy range from 0.25 GeV to {approx}3 GeV. We measure the interaction rates with 6-15% precision, and the cross sections with 10-30% precision. We also made an energy integrated measurements, with the precisions of 3% for the rate, and 8% for the cross section measurements. This is the first measurement of the CC inclusive cross section on carbon around 1 GeV. This inclusive interaction measurement is nearly free from effects of hadron re-interactions in the nucleus. Hence, it is complementary to other exclusive cross section measurements, and essential to understand the neutrino interaction cross sections in the few GeV region, which is relevant to ongoing and future neutrino oscillation experiments. This analysis also provides the normalization for SciBooNE's previous cross section ratio measurements for charged current coherent pion production and neutral current neutral pion production. Then, a precise comparison between our previous measurements and the model predictions becomes possible. The result of the interaction rate measurement is used to constrain the product of the neutrino flux and the cross section at the other experiment on the Fermilab Booster Neutrino Beam: Mini-BooNE. We conducted a search for short-baseline muon neutrino disappearance using data both from SciBooNE and MiniBooNE, to test a possible neutrino oscillation with sterile neutrinos which is suggested by the LSND experiment. With this constraint by SciBooNE, we significantly reduced the flux and the cross section uncertainties at MiniBooNE, and achieved the world best sensitivity for the {nu}{sub {mu}} disappearance at 0.5 < {Delta}m{sup 2} < 30 (eV{sup 2}). We found no significant oscillation signal, and set one of the world strongest limits for the sterile neutrino models.

Nakajima, Yasuhiro; /Kyoto U.

2011-01-01T23:59:59.000Z

358

Longevity Problem of Sterile Neutrino Dark Matter  

E-Print Network (OSTI)

Sterile neutrino dark matter of mass O(1-10) keV decays into an active neutrino and an X-ray photon, and the non-observation of the corresponding X-ray line requires the sterile neutrino to be more long-lived than estimated based on the seesaw formula : the longevity problem. We show that, if one or more of the B-L Higgs fields are charged under a flavor symmetry (or discrete R symmetry), the split mass spectrum for the right-handed neutrinos as well as the required longevity is naturally realized. We provide several examples in which the predicted the X-ray flux is just below the current bound.

Hiroyuki Ishida; Kwang Sik Jeong; Fuminobu Takahashi

2013-09-12T23:59:59.000Z

359

Precision spectroscopy with reactor anti-neutrinos  

E-Print Network (OSTI)

In this work we present an accurate parameterization of the anti-neutrino flux produced by the isotopes 235U, 239Pu and 241Pu in nuclear reactors. We determine the coefficients of this parameterization, as well as their covariance matrix, by performing a fit to spectra inferred from experimentally measured beta spectra. Subsequently we show that flux shape uncertainties play only a minor role in the KamLAND experiment, however, we find that future reactor neutrino experiments to measure the mixing angle $\\theta_{13}$ are sensitive to the fine details of the reactor neutrino spectra. Finally, we investigate the possibility to determine the isotopic composition in nuclear reactors through an anti-neutrino measurement. We find that with a 3 month exposure of a one ton detector the isotope fractions and the thermal reactor power can be determined at a few percent accuracy, which may open the possibility of an application for safeguard or non-proliferation objectives.

Huber, P; Huber, Patrick; Schwetz, Thomas

2004-01-01T23:59:59.000Z

360

QLC relation and neutrino mass hierarchy  

E-Print Network (OSTI)

neutrino mass matrix is generated at high energies, s 12 = cneutrino mass matrix is generated at low energy scales. Ontrino mass matrix is generated at some high energy scale. We

Ferrandis, Javier

2009-01-01T23:59:59.000Z

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361

Experimental and phenomenological status of neutrino ... - Springer  

Science Conference Proceedings (OSTI)

1 kt water Cerenkov and a fine grained water tube with scintillation fibre 6 ton detector. This way the neutrino flux is accurately known. The final result of the.

362

Neutrino Oscillation Experiments at Nuclear Reactors  

E-Print Network (OSTI)

In this paper I give an overview of the status of neutrino oscillation experiments performed using nuclear reactors as sources of neutrinos. I review the present generation of experiments (Chooz and Palo Verde) with baselines of about 1 km as well as the next generation that will search for oscillations with a baseline of about 100 km. While the present detectors provide essential input towards the understanding of the atmospheric neutrino anomaly, in the future, the KamLAND reactor experiment represents our best opportunity to study very small mass neutrino mixing in laboratory conditions. In addition KamLAND with its very large fiducial mass and low energy threshold, will also be sensitive to a broad range of different physics.

Giorgio Gratta

1999-05-06T23:59:59.000Z

363

Neutrino nuclear response and photo nuclear reaction  

E-Print Network (OSTI)

Photo nuclear reactions are shown to be used for studying neutrino/weak nuclear responses involved in astro-neutrino nuclear interactions and double beta decays. Charged current weak responses for ground and excited states are studied by using photo nuclear reactions through isobaric analog states of those states, while neutral current weak responses for excited states are studied by using photo nuclear reactions through the excited states. The weak interaction strengths are studied by measuring the cross sections of the photo nuclear reactions, and the spin and parity of the state are studied by measuring angular correlations of particles emitted from the photo nuclear reactions. Medium-energy polarized photons obtained from laser photons scattered off GeV electrons are very useful. Nuclear responses studied by photo nuclear reactions are used to evaluate neutrino/weak nuclear responses, i.e. nuclear beta and double beta matrix elements and neutrino nuclear interactions, and to verify theoretical calculation...

Ejiri, H; Boswell, M; Young, A

2013-01-01T23:59:59.000Z

364

Neutrino nuclear response and photo nuclear reaction  

E-Print Network (OSTI)

Photo nuclear reactions are shown to be used for studying neutrino/weak nuclear responses involved in astro-neutrino nuclear interactions and double beta decays. Charged current weak responses for ground and excited states are studied by using photo nuclear reactions through isobaric analog states of those states, while neutral current weak responses for excited states are studied by using photo nuclear reactions through the excited states. The weak interaction strengths are studied by measuring the cross sections of the photo nuclear reactions, and the spin and parity of the state are studied by measuring angular correlations of particles emitted from the photo nuclear reactions. Medium-energy polarized photons obtained from laser photons scattered off GeV electrons are very useful. Nuclear responses studied by photo nuclear reactions are used to evaluate neutrino/weak nuclear responses, i.e. nuclear beta and double beta matrix elements and neutrino nuclear interactions, and to verify theoretical calculations for them.

H. Ejiri; A. I. Titov; M. Boswell; A. Young

2013-11-10T23:59:59.000Z

365

BNL | Long Baseline Neutrino Experiment (LBNE)  

NLE Websites -- All DOE Office Websites (Extended Search)

through the Earth's mantle before striking its target at the Homestake Mine in Lead, South Dakota. This distance, not much more than a blink for speedy neutrinos, gives the...

366

Protoneutron star evolution and the neutrino-driven wind in general relativistic neutrino radiation hydrodynamics simulations  

SciTech Connect

Massive stars end their lives in explosions with kinetic energies on the order of 10{sup 51} erg. Immediately after the explosion has been launched, a region of low density and high entropy forms behind the ejecta, which is continuously subject to neutrino heating. The neutrinos emitted from the remnant at the center, the protoneutron star (PNS), heat the material above the PNS surface. This heat is partly converted into kinetic energy, and the material accelerates to an outflow that is known as the neutrino-driven wind. For the first time we simulate the collapse, bounce, explosion, and the neutrino-driven wind phases consistently over more than 20 s. Our numerical model is based on spherically symmetric general relativistic radiation hydrodynamics using spectral three-flavor Boltzmann neutrino transport. In simulations where no explosions are obtained naturally, we model neutrino-driven explosions for low- and intermediate-mass Fe-core progenitor stars by enhancing the charged current reaction rates. In the case of a special progenitor star, the 8.8 M{circle_dot} O-Ne-Mg-core, the explosion in spherical symmetry was obtained without enhanced opacities. The post-explosion evolution is in qualitative agreement with static steady-state and parametrized dynamic models of the neutrino-driven wind. On the other hand, we generally find lower neutrino luminosities and mean neutrino energies, as well as a different evolutionary behavior of the neutrino luminosities and mean neutrino energies. The neutrino-driven wind is proton-rich for more than 10 s and the contraction of the PNS differs from the assumptions made for the conditions at the inner boundary in previous neutrino-driven wind studies. Despite the moderately high entropies of about 100 k{sub B}/baryon and the fast expansion timescales, the conditions found in our models are unlikely to favor r-process nucleosynthesis. The simulations are carried out until the neutrino-driven wind settles down to a quasi-stationary state. About 5 s after the bounce, the peak temperature inside the PNS already starts to decrease because of the continued deleptonization. This moment determines the beginning of a cooling phase dominated by the emission of neutrinos. We discuss the physical conditions of the quasi-static PNS evolution and take the effects of deleptonization and mass accretion from early fallback into account.

Fischer, T. [University of Basel; Mezzacappa, Anthony [ORNL; Thielemann, F.-K. [University of Basel; Liebendoerfer, M. [University of Basel; Whitehouse, S. [University of Basel

2010-01-01T23:59:59.000Z

367

Megaton Water Cerenkov Detectors and Astrophysical Neutrinos  

E-Print Network (OSTI)

Although formal proposals have not yet been made, the UNO and Hyper-Kamiokande projects are being developed to follow-up the tremendously successful program at Super-Kamiokande using a detector that is 20-50 times larger. The potential of such a detector to continue the study of astrophysical neutrinos is considered and contrasted with the program for cubic kilometer neutrino observatories.

Maury Goodman

2005-01-21T23:59:59.000Z

368

Megaton Water Cerenkov Detectors and Astrophysical Neutrinos  

E-Print Network (OSTI)

Although formal proposals have not yet been made, the UNO and Hyper-Kamiokande projects are being developed to follow-up the tremendously successful program at Super-Kamiokande using a detector that is 20-50 times larger. The potential of such a detector to continue the study of astrophysical neutrinos is considered and contrasted with the program for cubic kilometer neutrino observatories. 1.

M. Goodman A

2005-01-01T23:59:59.000Z

369

Neutrino Factory Physics Study Plots  

NLE Websites -- All DOE Office Websites (Extended Search)

Plots Plots Kerrys Plot Area Rajas Plot Area Superbeams draft report Steves Talk at the 2 day meeting for the neutrino factory physics study, 17-18 Feb, 2000. sin2 2theta(13) reach summary plot Superbeam plots Fig. 3 for superbeams paper Very long baseline conventional beam setup at FNAL Decay channel length versus baseline for conventional beams at FNAL Pion decay fraction versus baseline for conventional beams at FNAL Superbeam sin**2 2theta(13) sensitivity vs E and L: Rate table for WBB, LAr Superbeam sin**2 2theta(13) sensitivity vs E and L: Rate table for NBB, water C NUMI medium energy beam, baseline 2800 km, s2 2theta(13) = 0.01 NUMI medium energy beam, baseline 2800 km, s2 2theta(13) = 0.04 Draft paper Figures for entry level and beyond paper Fig. X1 Wrong-sign muon CC interaction spectrum versus muon

370

Earthquake Forecast via Neutrino Tomography  

E-Print Network (OSTI)

We discuss the possibility of forecasting earthquakes by means of (anti)neutrino tomography. Antineutrinos emitted from reactors are used as a probe. As the antineutrinos traverse through a region prone to earthquakes, observable variations in the matter effect on the antineutrino oscillation would provide a tomography of the vicinity of the region. In this preliminary work, we adopt a simplified model for the geometrical profile and matter density in a fault zone. We calculate the survival probability of electron antineutrinos for cases without and with an anomalous accumulation of electrons which can be considered as a clear signal of the coming earthquake, at the geological region with a fault zone, and find that the variation may reach as much as 3% for $\\bar \

Bin Wang; Ya-Zheng Chen; Xue-Qian Li

2010-01-17T23:59:59.000Z

371

Status of the LBNE Neutrino Beamline  

SciTech Connect

The Long Baseline Neutrino Experiment (LBNE) will utilize a neutrino beamline facility located at Fermilab to carry out a compelling research program in neutrino physics. The facility will aim a beam of neutrinos toward a detector placed at the Homestake Mine in South Dakota. The neutrinos are produced in a three-step process. First, protons from the Main Injector (60-120 GeV) hit a solid target and produce mesons. Then, the charged mesons are focused by a set of focusing horns into the decay pipe, towards the far detector. Finally, the mesons that enter the decay pipe decay into neutrinos. The parameters of the facility were determined taking into account several factors including the physics goals, the Monte Carlo modeling of the facility, spacial and radiological constraints and the experience gained by operating the NuMI facility at Fermilab. The initial beam power is expected to be {approx}700 kW, however some of the parameters were chosen to be able to deal with a beam power of 2.3 MW. We discuss here the status of the conceptual design and the associated challenges.

Papadimitriou, Vaia; /Fermilab

2011-12-01T23:59:59.000Z

372

Accelerator-based neutrino oscillation experiments  

SciTech Connect

Neutrino oscillations were first discovered by experiments looking at neutrinos coming from extra-terrestrial sources, namely the sun and the atmosphere, but we will be depending on earth-based sources to take many of the next steps in this field. This article describes what has been learned so far from accelerator-based neutrino oscillation experiments, and then describe very generally what the next accelerator-based steps are. In section 2 the article discusses how one uses an accelerator to make a neutrino beam, in particular, one made from decays in flight of charged pions. There are several different neutrino detection methods currently in use, or under development. In section 3 these are presented, with a description of the general concept, an example of such a detector, and then a brief discussion of the outstanding issues associated with this detection technique. Finally, section 4 describes how the measurements of oscillation probabilities are made. This includes a description of the near detector technique and how it can be used to make the most precise measurements of neutrino oscillations.

Harris, Deborah A.; /Fermilab

2007-12-01T23:59:59.000Z

373

Radiochemical Solar Neutrino Experiments - Successful and Otherwise.  

SciTech Connect

Over the years, several different radiochemical systems have been proposed as solar neutrino detectors. Of these, two achieved operating status and obtained important results that helped to define the current field of neutrino physics: the first solar-neutrino experiment, the Chlorine Detector ({sup 37}Cl) that was developed by chemist Raymond Davis and colleagues at the Homestake Mine, and the subsequent Gallium ({sup 71}Ga) Detectors that were operated by (a) the SAGE collaboration at the Baksan Laboratory and (b) the GALLEX/GNO collaborations at the Gran Sasso National Laboratory. These experiments have been extensively discussed in the literature and in many previous International Neutrino Conferences. In this paper, I present important updates to the results from SAGE and GALLEX/GNO. I also review the principles of the radiochemical detectors and briefly describe several different detectors that have been proposed. In light of the well-known successes that have been subsequently obtained by real-time neutrino detectors such as Kamiokande, Super-Kamiokande, SNO, and KamLAND, I do not anticipate that any new radiochemical neutrino detectors will be built. At present, only SAGE is still operating; the Chlorine and GNO radiochemical detectors have been decommissioned and dismantled.

Hahn,R.L.

2008-05-25T23:59:59.000Z

374

Solar neutrino analysis of Super-Kamiokande  

E-Print Network (OSTI)

Super-Kamiokande-IV data taking began in September of 2008, and with upgraded electronics and improvements to water system dynamics, calibration and analysis techniques, a clear solar neutrino signal could be extracted at recoil electron kinetic energies as low as 3.5 MeV. The SK-IV extracted solar neutrino flux between 3.5 and 19.5 MeV is found to be (2.36$\\pm$0.02(stat.)$\\pm$0.04(syst.))$\\times 10^6$ /(cm$^2$sec). The SK combined recoil electron energy spectrum favors distortions predicted by standard neutrino flavour oscillation parameters over a flat suppression at 1$\\sigma$ level. A maximum likelihood fit to the amplitude of the expected solar zenith angle variation of the elastic neutrino-electron scattering rate in SK, results in a day/night asymmetry of $-3.2\\pm1.1$(stat.)$\\pm$0.5(syst.)$%$. The 2.7 $\\sigma$ significance of non-zero asymmetry is the first indication of the regeneration of electron type solar neutrinos as they travel through Earth's matter. A fit to all solar neutrino data and KamLAND yields $\\sin^2 \\theta_{12} = 0.304 \\pm 0.013$, $\\sin^2 \\theta_{13} = 0.031^{+0.017}_{-0.015}$ and $\\Delta m^2_{21} = 7.45^{+0.20}_{-0.19} \\times 10^{-5} {\\rm eV}^2$.

Hiroyuki Sekiya; for the Super-Kamiokande Collaboration

2013-07-14T23:59:59.000Z

375

Theory of Neutrinos: A White Paper  

E-Print Network (OSTI)

During 2004, four divisions of the American Physical Society commissioned a study of neutrino physics to take stock of where the field is at the moment and where it is going in the near and far future. Several working groups looked at various aspects of this vast field. The summary was published as a main report entitled ``The Neutrino Matrix'' accompanied by short 50 page versions of the report of each working group. Theoretical research in this field has been quite extensive and touches many areas and the short 50 page report provided only a brief summary and overview of few of the important points. The theory discussion group felt that it may be of value to the community to publish the entire study as a white paper and the result is the current article. After a brief overview of the present knowledge of neutrino masses and mixing and some popular ways to probe the new physics implied by recent data, the white paper summarizes what can be learned about physics beyond the Standard Model from the various proposed neutrino experiments. It also comments on the impact of the experiments on our understanding of the origin of the matter-antimatter asymmetry of the Universe and the basic nature of neutrino interactions as well as the existence of possible additional neutrinos. Extensive references to original literature are provided.

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

2005-10-17T23:59:59.000Z

376

Neutrino Beams for Scattering Experiment  

NLE Websites -- All DOE Office Websites (Extended Search)

Options for Neutrino Scattering Measurements Options for Neutrino Scattering Measurements Draft Skeleton Table Beam Characteristics K2K CERN AD FNAL Debuncher FNAL Booster NuMI LE NuMI ME NuMI HE Peak E(nu) (GeV) X X ~2.5 1 3.5 7.5 13 Maximum E(nu) (GeV) (->1% peak rate) X X 8.9 3 50 50+ 50+ Nu(mu) CC Rate (per ton-year) X 1.4 0 5,000 210,000 1,100,000 2,000,000 Nubar(mu) CC Rate (per ton-year) X 3.4 ~18 (Time Separated) ~360 (Prompt) 1,000 21,000 32,000 20,000 Nu(e) CC Rate (per ton-year) X 0 0 1 2,300 9,500 12,000 Nubar(e) CC Rate (per ton-year) X 0.4 ~18 (Time Separated) 0.5 630 660 600 Flux uncertainty X X 10% 10% 20% 20% 20% QE events / 100 ton-years X 169 nubar(mu) 47 nu(mu) 17 nubar(e) 525 nubar(e) 500,000 nu(mu) 100,000 nu(mu) X X X Floor space (m**2) X X New Hall New Hall 20 x 2.5 20 x 2.5 20 x 2.5 Run Type X X Parasitic Parasitic Parasitic Parasitic Parasitic

377

Measuring the Higgs Boson's Parity Using tau -> rho nu  

SciTech Connect

We present a very promising method for a measurement of the Higgs boson parity using the H/A {yields} {tau}{sup +}{tau}{sup -} {yields} {rho}{sup +}{bar {nu}}{sub {tau}}{rho}{sup -}{nu}{sub {tau}} {yields} {pi}{sup +}{pi}{sup 0} {bar {nu}}{sub {tau}} {pi}{sup -}{pi}{sup 0} {nu}{sub {tau}} decay chain. The method is both model independent and independent of the Higgs production mechanism. Angular distributions of the {tau} decay products which are sensitive to the Higgs boson parity are defined and are found to be measurable using typical properties of a future detector for an e{sup +}e{sup -} linear collider. The prospects for the measurement of the parity of a Higgs boson with a mass of 120 GeV are quantified for the case of e{sup +}e{sup -} collisions of 500 GeV center of mass energy with an integrated luminosity of 500fb{sup -1}. The Standard Model Higgsstrahlung production process is used as an example.

Bower, Gary

2002-08-08T23:59:59.000Z

378

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

E-Print Network (OSTI)

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 + -...

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

2003-01-01T23:59:59.000Z

379

The Palo Verde Reactor Neutrino Experiment A Test for Long Baseline Neutrino Oscillations  

E-Print Network (OSTI)

\\Gamma3 eV 2 and sin 2 2\\Theta ! 0:1. Our range of sensitivity is tuned to test the š ¯ $ š e solutionThe Palo Verde Reactor Neutrino Experiment A Test for Long Baseline Neutrino Oscillations Presented 85287 S. Pittalwala, R. Wilferd, S. Young Palo Verde Nuclear Generating Station, Tonopah AZ 85354 Our

Piepke, Andreas G.

380

Spectroscopy of low energy solar neutrinos by MOON -Mo Observatory Of Neutrinos-  

E-Print Network (OSTI)

Spectroscopy of low energy solar neutrinos by MOON -Mo Observatory Of Neutrinos- R. Hazamaa , P Be solar 's. The present status of MOON for the low energy solar experiment is briefly discussed the pp solar flux with good accuracy. 1. INTRODUCTION Realtime studies of the high-energy component of 8

Washington at Seattle, University of

Note: This page contains sample records for the topic "tau neutrinos heavy" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

HEAVY-ION RADIOGRAPHY AND HEAVY-ION COMPUTED TOMOGRAPHY  

E-Print Network (OSTI)

In: Biological and Medical Research with Accelerated Heavyeds. Biological and Medical Research with Accelerated HeavyIn: Biological and Medical Research with Accelerated Heavy

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

382

Cosmological bounds on neutrino degeneracy improved by flavor oscillations  

E-Print Network (OSTI)

We study three-flavor neutrino oscillations in the early universe in the presence of neutrino chemical potentials. We take into account all effects from the background medium, i.e. collisional damping, the refractive effects from charged leptons, and in particular neutrino self-interactions that synchronize the neutrino oscillations. We find that effective flavor equilibrium between all active neutrino species is established well before the big-bang nucleosynthesis (BBN) epoch if the neutrino oscillation parameters are in the range indicated by the atmospheric neutrino data and by the large mixing angle (LMA) MSW solution of the solar neutrino problem. For the other solutions of the solar neutrino problem, partial flavor equilibrium may be achieved if the angle theta_13 is close to the experimental limit tan^2(theta_13)radiation contribution from degenerate neutrinos is limited to such low values that it is neither observable in the large-scale structure of the universe nor in the anisotropies of the cosmic microwave background radiation. Existing limits and possible future measurements, for example in KATRIN, of the absolute neutrino mass scale will provide unambiguous information on the cosmic neutrino mass density, essentially free of the uncertainty of the neutrino chemical. potentials.

A. D. Dolgov; S. H. Hansen; S. Pastor; S. T. Petcov; G. G. Raffelt; D. V. Semikoz

2002-01-30T23:59:59.000Z

383

Effect of microtubule-associated protein tau in dynamics of single-headed motor proteins KIF1A  

E-Print Network (OSTI)

Intracellular transport based on molecular motors and its regulation are crucial to the functioning of cells. Filamentary tracks of the cells are abundantly decorated with non-motile microtubule-associated proteins, such as tau. Motivated by experiments on kinesin-tau interactions [Dixit et al. Science 319, 1086 (2008)] we developed a stochastic model of interacting single-headed motor proteins KIF1A that also takes into account the interactions between motor proteins and tau molecules. Our model reproduce experimental observations and predicts significant effects of tau on bound time and run length which suggest an important role of tau in regulation of kinesin-based transport.

J. Sparacino; M. G. Faras; P. W. Lamberti

2013-02-11T23:59:59.000Z

384

Science and Technology of BOREXINO: A Real Time Detector for Low Energy Solar Neutrinos SOLAR NEUTRINOS  

E-Print Network (OSTI)

BOREXINO, a real-time device for low energy neutrino spectroscopy is nearing completion of construction in the underground laboratories at Gran Sasso, Italy (LNGS). The experiment's goal is the direct measurement of the flux of 7Be solar neutrinos of all flavors via neutrino-electron scattering in an ultra-pure scintillation liquid. Seeded by a series of innovations which were brought to fruition by large scale operation of a 4-ton test detector at LNGS, a new technology has been developed for BOREXINO. It enables sub-MeV solar neutrino spectroscopy for the first time. This paper describes the design of BOREXINO, the various facilities essential to its operation, its spectroscopic and background suppression capabilities and a prognosis of the impact of its results towards resolving the solar neutrino problem. BOREXINO will also address several other frontier questions in particle physics, astrophysics and geophysics.

Borexino Collaboration; G. Alimonti

2000-12-11T23:59:59.000Z

385

Search for Second-Class Currents in \\tau^-\\to\\omega\\pi^-\  

SciTech Connect

We report on an analysis of {tau}{sup -} decaying into {omega}{pi}{sup -}{nu}{sub {tau}} with {omega} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0} using data containing nearly 320 million tau pairs collected with the BABAR detector at the PEP-II asymmetric energy B-Factory. We find no evidence for second-class currents and set an upper limit at 0.69% at a 90% confidence level for the ratio of second- to first-class currents.

Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Lopez, L.; Palano, Antimo; Pappagallo, M.; /Bari U. /INFN, Bari; Eigen, G.; Stugu, Bjarne; Sun, L.; /Bergen U.; Abrams, G.S.; Battaglia, M.; Brown, D.N.; Cahn, Robert N.; Jacobsen, R.G.; /LBL, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /Consorzio Milano Ricerche /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Napoli Seconda U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /INFN, Pisa /Princeton U. /Banca di Roma /Frascati /Rostock U. /Rutherford /DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

2008-09-03T23:59:59.000Z

386

Signals of CPT Violation and Non-Locality in Future Neutrino Oscillation Experiments  

E-Print Network (OSTI)

We investigate the sensitivities of future neutrino oscillation experiments for measuring the neutrino mass squared differences and leptonic mixing angles independently with neutrinos and anti-neutrinos. We update the expected sensitivities of Neutrino Factories to the ``atmospheric'' (anti-)neutrino parameters using an optimized setup. A dedicated beta-Beam facility, in combination with a SPMIN reactor experiment, could give excellent sensitivities also to the ``solar'' parameters, for neutrinos and anti-neutrinos respectively. A signal of a different mass matrix for neutrinos and anti-neutrinos would imply CPT violation and non-locality of the underlying particle theory.

Antusch, S

2008-01-01T23:59:59.000Z

387

Signals of CPT Violation and Non-Locality in Future Neutrino Oscillation Experiments  

E-Print Network (OSTI)

We investigate the sensitivities of future neutrino oscillation experiments for measuring the neutrino mass squared differences and leptonic mixing angles independently with neutrinos and anti-neutrinos. We update the expected sensitivities of Neutrino Factories to the "atmospheric" (anti-)neutrino parameters using an optimized setup. A dedicated beta-Beam facility, in combination with a SPMIN reactor experiment, could give excellent sensitivities also to the "solar" parameters, for neutrinos and anti-neutrinos respectively. A signal of a different mass matrix for neutrinos and anti-neutrinos would imply CPT violation and non-locality of the underlying particle theory.

S. Antusch; E. Fernandez-Martinez

2008-04-17T23:59:59.000Z

388

Fermilab | Recovery Act | Long-baseline neutrino research  

NLE Websites -- All DOE Office Websites (Extended Search)

Long-baseline neutrino research Long-baseline neutrino research The proposed long-baseline neutrino project will place a particle detector at great depth underground to study neutrinos from an intense beam generated several states away. Researchers from six American laboratories and more than two dozen universities, most in the United States, have proposed plans to generate an intense beam of neutrinos at Fermilab and to place the detector in the Homestake Gold Mine near Lead, South Dakota. It would be the world's deepest underground laboratory, hosting experiments as deep as 8,000 feet underground. Neutrinos are the most abundant but perhaps least understood particles in our galaxy. Scientists hope to observe the neutrinos changing from one type to another as they travel. Studying a neutrino beam at two locations a

389

Report of the APS Neutrino Study Reactor Working Group  

E-Print Network (OSTI)

the A P S Neutrino Study Reactor Working Group E. Abouzaid,2004 Contents Introduction A Reactor E x p e r i m e n t to3 Strategies to Improve on Past Reactor Neutrino Oscillation

2004-01-01T23:59:59.000Z

390

Low-multiplicity Burst Search at the Sudbury Neutrino Observatory  

E-Print Network (OSTI)

Results are reported from a search for low-multiplicity neutrino bursts in the Sudbury Neutrino Observatory. Such bursts could indicate the detection of a nearby core-collapse supernova explosion. The data were taken from ...

Chen, Min

391

doi:10.1093/nar/gkr195 Regulation of the alternative splicing of tau exon 10 by SC35 and Dyrk1A  

E-Print Network (OSTI)

Abnormal alternative splicing of tau exon 10 results in imbalance of 3R-tau and 4R-tau expression, which is sufficient to cause neurofibrillary degeneration. Splicing factor SC35, a member of the superfamily of the serine/arginine-rich (SR) proteins, promotes tau exon 10 inclusion. The molecular mechanism by which SC35 participates in tau exon 10 splicing remains elusive. In the present study, we found that tau pre-mRNA was coprecipitated by SC35 tagged with HA. Mutation of the SC35-like exonic splicing enhancer located at exon 10 of tau affected both the binding of SC35 to tau pre-mRNA and promotion of tau exon 10 inclusion, suggesting that SC35 acts on the SC35-like exonic splicing enhancer to promote tau exon 10 inclusion. Dyrk1A (dual-specificity tyrosine-phosphorylated and regulated kinase 1A) phosphorylated SC35 in vitro and interacted with it in cultured cells. Overexpression of Dyrk1A suppressed SC350s ability to promote tau exon 10 inclusion. Downregulation of Dyrk1A promoted 4R-tau expression. Therefore, upregulation of Dyrk1A in Down syndrome brain or Alzheimers brain may cause dysregulation of tau exon 10 splicing through SC35, and probably together with other splicing factors, leading to the imbalance in 3R-tau and 4R-tau expression, which may initiate or accelerate tau pathology and cause neurofibrillary degeneration in the diseases.

Wei Qian; Hongwei Liang; Jianhua Shi; Nana Jin; Inge Grundke-iqbal; Khalid Iqbal; Cheng-xin Gong; Fei Liu

2010-01-01T23:59:59.000Z

392

Search for new heavy charged gauge bosons  

SciTech Connect

Additional gauge bosons are introduced in many theoretical extensions to the Standard Model. A search for a new heavy charged gauge boson W{prime} decaying into an electron and a neutrino is presented. The data used in this analysis was taken with the D0 detector at the Fermilab proton-antiproton collider at a center-of-mass energy of 1.96 TeV and corresponds to an integrated luminosity of about 1 fb{sup -1}. Since no significant excess is observed in the data, an upper limit is set on the production cross section times branching fraction {sigma}{sub W{prime}}xBr (W{prime} {yields} e{nu}). Using this limit, a W{prime} boson with mass below {approx}1 TeV can be excluded at the 95% confidence level assuming that the new boson has the same couplings to fermions as the Standard Model W boson.

Magass, Carsten Martin; /RWTH Aachen U.

2007-11-01T23:59:59.000Z

393

Core-Collapse Supernovae Induced by Anisotropic Neutrino Radiation  

E-Print Network (OSTI)

We demonstrate the important role of anisotropic neutrino radiation on the mechanism of core-collapse supernova explosions. Through a new parameter study with a fixed radiation field of neutrinos, we show that prolate explosions caused by globally anisotropic neutrino radiation is the most effective mechanism of increasing the explosion energy when the total neutrino luminosity is given. This is suggestive of the fact that the expanding materials of SN 1987A has a prolate geometry.

Yuko Motizuki; Hideki Madokoro; Tetsuya Shimizu

2004-06-11T23:59:59.000Z

394

Atmospheric neutrino flux at INO, South Pole and Pyhsalmi  

E-Print Network (OSTI)

We present the calculation of the atmospheric neutrino fluxes for the neutrino experiments proposed at INO, South Pole and Pyh\\"asalmi. Neutrino fluxes have been obtained using ATMNC, a simulation code for cosmic ray in the atmosphere. Even using the same primary flux model and the interaction model, the calculated atmospheric neutrino fluxes are different for the different sites due to the geomagnetic field. The prediction of these fluxes in the present paper would be quite useful in the experimental analysis.

M. Sajjad Athar; M. Honda; T. Kajita; K. Kasahara; S. Midorikawa

2012-10-18T23:59:59.000Z

395

Probing Active to Sterile Neutrino Oscillations in the LENS Detector  

E-Print Network (OSTI)

Sterile neutrino conversion in meter scale baselines can be sensitively probed using monoenergetic, sub-MeV, flavor pure e-neutrinos from an artificial MCi source and the unique technology of LENS designed to oberve the low energy solar neutrino spectrum via tagged CC e-neutrino capture in 115-In. Active-sterile oscillations can be directly observed in the granular LENS detector itself to critically test and extend resuls of short baseline accelerator and reactor experiments.

Christian Grieb; Jonathan Link; R. S. Raghavan

2006-11-13T23:59:59.000Z

396

Multinucleon Ejection Model for Two Body Current Neutrino Interactions  

Science Conference Proceedings (OSTI)

A model is proposed to describe nucleons ejected from a nucleus as a result of two-body-current neutrino interactions. The model can be easily implemented in Monte Carlo neutrino event generators. Various possibilities to measure the two-body-current contribution are discussed. The model can help identify genuine charge current quasielastic events and allow for a better determination of the systematic error on neutrino energy reconstruction in neutrino oscillation experiments.

Sobczyk, Jan T.; /Fermilab

2012-06-01T23:59:59.000Z

397

A Sterile Neutrino Search with Kaon Decay-at-rest  

E-Print Network (OSTI)

Monoenergetic muon neutrinos (235.5 MeV) from positive kaon decay-at-rest are considered as a source for an electron neutrino appearance search. In combination with a liquid argon time projection chamber based detector, such a source could provide discovery-level sensitivity to the neutrino oscillation parameter space indicative of a sterile neutrino. Current and future intense >3 GeV kinetic energy proton facilities around the world can be employed for this experimental concept.

J. Spitz

2012-03-27T23:59:59.000Z

398

Neutrino experiments in Physics Department of Rome Sapienza University  

E-Print Network (OSTI)

This paper describes the history of experimental neutrino physics in the physics department of Rome Sapienza University

Dore, Ubaldo

2013-01-01T23:59:59.000Z

399

Sterile Neutrino Search Using China Advanced Research Reactor  

E-Print Network (OSTI)

We study the feasibility of a sterile neutrino search at the China Advanced Research Reactor by measuring $\\bar {\

Guo, Gang; Ji, Xiangdong; Liu, Jianglai; Xi, Zhaoxu; Zhang, Huanqiao

2013-01-01T23:59:59.000Z

400

Confronting mass-varying neutrinos with MiniBooNE  

E-Print Network (OSTI)

We study the proposal that mass-varying neutrinos could provide an explanation for the LSND signal for \\bar\

V. Barger; D. Marfatia; K. Whisnant

2005-09-16T23:59:59.000Z

Note: This page contains sample records for the topic "tau neutrinos heavy" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Conformal Neutrinos: an Alternative to the See-saw Mechanism  

E-Print Network (OSTI)

We analyze a scenario where the right-handed neutrinos make part of a strongly coupled conformal field theory and acquire an anomalous dimension \\gamma1/2 giving rise to an inverse see-saw mechanism. In this case light sterile neutrinos do appear and neutrino oscillation experiments are able to probe our model.

Gero von Gersdorff; Mariano Quiros

2008-12-30T23:59:59.000Z

402

Constraint on super-luminal neutrinos from vacuum Cerenkov processes  

E-Print Network (OSTI)

We examine the Cerenkov-like emission of $e^+ e^-$ from muon super-luminal muon neutrinos assuming a quadratic energy dependence of the neutrino velocity arising from Lorentz violating interactions. We find that with the OPERA result for the neutrino-photon velocity difference, the decay length for the process $\

Subhendra Mohanty; Soumya Rao

2011-11-11T23:59:59.000Z

403

Spin light mode of massive neutrino radiative decay in matter  

E-Print Network (OSTI)

Using the exact solutions for the Dirac neutrino wave function in presence of matter we study the spin light mode in the process of neutrino transition from initial heavier to final lighter state. The spin light is emitted due to the neutrino nonzero transitional magnetic moment.

Alexander Grigoriev; Alexey Lokhov; Alexander Studenikin

2009-12-31T23:59:59.000Z

404

Uncertainties in the Anti-neutrino Production at Nuclear Reactors  

E-Print Network (OSTI)

Anti-neutrino emission rates from nuclear reactors are determined from thermal power measurements and fission rate calculations. The uncertainties in these quantities for commercial power plants and their impact on the calculated interaction rates in electron anti-neutrino detectors is examined. We discuss reactor-to-reactor correlations between the leading uncertainties and their relevance to reactor anti-neutrino experiments.

Z. Djurcic; J. A. Detwiler; A. Piepke; V. R. Foster Jr.; L. Miller; G. Gratta

2008-08-06T23:59:59.000Z

405

Uncertainties in the Anti-neutrino Production at Nuclear Reactors  

E-Print Network (OSTI)

Anti-neutrino emission rates from nuclear reactors are determined from thermal power measurements and fission rate calculations. The uncertainties in these quantities for commercial power plants and their impact on the calculated interaction rates in electron anti-neutrino detectors is examined. We discuss reactor-to-reactor correlations between the leading uncertainties and their relevance to reactor anti-neutrino experiments.

Djurcic, Z; Piepke, A; Foster, V R; Miller, L; Gratta, G

2008-01-01T23:59:59.000Z

406

Future neutrino oscillation facilities: physics priorities and open issues  

E-Print Network (OSTI)

The recent discovery that neutrinos have mass opens a wide new field of experimentation. Accelerator-made neutrinos are essential. Ideas for future facilities include superbeams beta-beams and neutrino factories, each associated with one or several options for detector systems. A summary of the perceived virtues and shortcomings of these options, and a number of open questions, are presented.

Alain Blondel

2006-01-19T23:59:59.000Z

407

Original neutrino fluxes and hidden mass in the universe  

Science Conference Proceedings (OSTI)

The status of neutrino experiments in connection with the fundamental problem of searches for a signal from dark matter is discussed. Limits on the magnitude of the effect of dark-matter-particle annihilation in the Sun that were obtained with neutrino telescopes are presented. In particular, the first results from the NT-200 Baikal Deep Underwater Neutrino Telescope are described.

Suvorova, O. V., E-mail: suvorova@cpc.inr.ac.ru [Russian Academy of Sciences, Institute for Nuclear Research (Russian Federation)

2011-01-15T23:59:59.000Z

408

Block Heavy Hitters  

E-Print Network (OSTI)

e study a natural generalization of the heavy hitters problem in thestreaming context. We term this generalization *block heavy hitters* and define it as follows. We are to stream over a matrix$A$, and report all *rows* ...

Andoni, Alexandr

2008-05-02T23:59:59.000Z

409

A study of tau identification with the CMS detector at the LHC  

E-Print Network (OSTI)

In this thesis I explore the identification of [tau] leptons from simulated reconstructed data that will be collected by the Compact Muon Solenoid (CMS) detector on the Large Hadron Collider (LHC) at CERN. The two components ...

Ilten, Philip James

2008-01-01T23:59:59.000Z

410

Limits on tau lepton-flavor violating decays into three charged leptons  

E-Print Network (OSTI)

A search for the neutrinoless, lepton-flavor violating decay of the ? [tau] lepton into three charged leptons has been performed using an integrated luminosity of 468??fb-1 [fb superscript -1] collected with the BABAR ...

Cowan, Ray Franklin

411

Search for Higgs decays to tau lepton pairs at the Tevatron  

E-Print Network (OSTI)

We present a search for neutral supersymmetric Higgs bosons decaying to tau+tau- pairs produced in ppbar collisions at sqrt{s}=1.96 TeV. The data have been collected with the CDF II and D0 detectors at the Tevatron collider at Fermilab (1 fb^-1 of integrated luminosity per experiment). No significant excess above the standard model backgrounds is observed. We set exclusion limits on the Higgs production cross-section times the branching fraction of its decay to tau+tau- pairs for Higgs masses in the range from 90 to 250 GeV/c^2. We also set exclusion limits on MSSM parameters m_A and tan_beta in several benchmark scenarios.

I. Kravchenko; for the CDF; D0 Collaborations

2007-10-26T23:59:59.000Z

412

Search for the Higgs boson in lepton, tau and jets final states  

E-Print Network (OSTI)

We present a search for the standard model Higgs boson in final states with an electron or muon and a hadronically decaying tau lepton in association with two or more jets using 9.7 fb^{-1} of Run II Fermilab Tevatron Collider data collected with the D0 detector. The analysis is sensitive to Higgs boson production via gluon fusion, associated vector boson production, and vector boson fusion, followed by the Higgs boson decay to tau lepton pairs or to W boson pairs. The ratios of 95% C.L. upper limits on the cross section times branching ratio to those predicted by the standard model are obtained for orthogonal subsamples that are enriched in either H -> tau tau decays or H -> WW decays, and for the combination of these subsample limits. The observed and expected limit ratios for the combined subsamples at a Higgs boson mass of 125 GeV are 11.3 and 9.0 respectively.

D0 Collaboration

2012-11-29T23:59:59.000Z

413

Effects of W/sub R/ and charged Higgs in the leptonic decay of /tau/  

Science Conference Proceedings (OSTI)

Experimental test of the existence of the right-hand W boson and the charged Higgs particle is suggested. The experiment involves measurement of muon polarization from the decay of polarized /tau/'s. 8 refs., 2 figs., 1 tab.

Tsai, Yung Su

1989-07-01T23:59:59.000Z

414

Selection of tau leptons with the CDF Run 2 trigger system  

SciTech Connect

We have implemented triggers for hadronically decaying tau leptons within a framework of the CDF Run 2 trigger system. We describe the triggers, along with their physics motivations, and report on their initial performance.

A. Anastassov; S. Baroiant; M. Chertok

2003-07-01T23:59:59.000Z

415

A Search for the Decay Modes B +/- to h +/- tau l  

SciTech Connect

We present a search for the lepton flavor violating decay modes B{sup {+-}} {yields} h{sup {+-}} {tau}{ell} (h = K, {pi}; {ell} = e, {mu}) using the BABAR data sample, which corresponds to 472 million B{bar B} pairs. The search uses events where one B meson is fully reconstructed in one of several hadronic final states. Using the momenta of the reconstructed B, h, and {ell} candidates, we are able to fully determine the {tau} four-momentum. The resulting {tau} candidate mass is our main discriminant against combinatorial background. We see no evidence for B{sup {+-}} {yields} h{sup {+-}} {tau}{ell} decays and set a 90% confidence level upper limit on each branching fraction at the level of a few times 10{sup -5}.

Lees, J.P.

2012-07-20T23:59:59.000Z

416

Neutrino Propagation in a Strongly Magnetized Medium  

E-Print Network (OSTI)

We derive general expressions at the one-loop level for the coefficients of the covariant structure of the neutrino self-energy in the presence of a constant magnetic field. The neutrino energy spectrum and index of refraction are obtained for neutral and charged media in the strong-field limit ($M_{W}\\gg \\sqrt{B}\\gg m_{e},T,\\mu ,| \\mathbf{p}| $) using the lowest Landau level approximation. The results found within the lowest Landau level approximation are numerically validated, summing in all Landau levels, for strong $B\\gg T^{2}$ and weakly-strong $B \\gtrsim T^{2}$ fields. The neutrino energy in leading order of the Fermi coupling constant is expressed as the sum of three terms: a kinetic-energy term, a term of interaction between the magnetic field and an induced neutrino magnetic moment, and a rest-energy term. The leading radiative correction to the kinetic-energy term depends linearly on the magnetic field strength and is independent of the chemical potential. The other two terms are only present in a charged medium. For strong and weakly-strong fields, it is found that the field-dependent correction to the neutrino energy in a neutral medium is much larger than the thermal one. Possible applications to cosmology and astrophysics are considered.

E. Elizalde; E. J. Ferrer; V. de la Incera

2004-04-26T23:59:59.000Z

417

The ANTARES neutrino telescope: a status report  

E-Print Network (OSTI)

ANTARES is a large volume neutrino telescope currently under construction off La Seyne-sur-mer, France, at 2475m depth. Neutrino telescopes aim at detecting neutrinos as a new probe for a sky study at energies greater than 1 TeV. The detection principle relies on the observation, using photomultipliers, of the Cherenkov light emitted by charged leptons induced by neutrino interactions in the surrounding detector medium. Since late January 2007, the ANTARES detector consists of 5 lines, comprising 75 optical detectors each, connected to the shore via a 40 km long undersea cable. The data from these lines not only allow an extensive study of the detector properties but also the reconstruction of downward going cosmic ray muons and the search for the first upward going neutrino induced muons.The operation of these lines follows on from that of the ANTARES instrumentation line, which has provided data for more than a year on the detector stability and the environmental conditions. The full 12 line detector is planned to be fully operational early 2008.

A. Kouchner; for the Antares collaboration

2007-10-01T23:59:59.000Z

418

Effects of Environment Dependence of Neutrino Mass versus Solar and Reactor Neutrino Data  

E-Print Network (OSTI)

In this work we study the phenomenological consequences of the environment dependence of neutrino mass on solar and reactor neutrino phenomenology. Such dependence can be induced, for example, by Yukawa interactions with a light scalar particle which couples to neutrinos and matter and it is expected, among others, in mass varying neutrino scenarios. Under the assumption of one mass scale dominance, we perform a global analysis of solar and KamLAND neutrino data which depends on 4 parameters: the two standard oscillation parameters, Delta m^2 and tan^2(theta), and two new coefficients, which parameterize the environment dependence of the neutrino mass. We find that, generically, the inclusion of the environment dependent terms does not lead to a very statistically significant improvement on the description of the data in the most favoured MSW LMA (or LMA-I) region. It does, however, substantially improve the fit in the high-Delta m^2 LMA (or LMA-II) region which can be allowed at 98.9% CL. Conversely the analysis allow us to place stringent constraints on the size of the environment dependence terms, which can be translated on a bound on the product of the effective neutrino-scalar (lambda^\

M. C. Gonzalez-Garcia; P. C. de Holanda; R. Zukanovich Funchal

2005-11-08T23:59:59.000Z

419

Neutrino mass hierarchy determination and other physics potential of medium-baseline reactor neutrino oscillation experiments  

E-Print Network (OSTI)

Medium-baseline reactor neutrino oscillation experiments (MBRO) have been proposed to determine the neutrino mass hierarchy (MH) and to make precise measurements of the neutrino oscillation parameters. With sufficient statistics, better than ~3%/\\sqrt{E} energy resolution and well understood energy non-linearity, MH can be determined by analyzing oscillation signals driven by the atmospheric mass-squared difference in the survival spectrum of reactor antineutrinos. With such high performance MBRO detectors, oscillation parameters, such as \\sin^22\\theta_{12}, \\Delta m^2_{21}, and \\Delta m^2_{32}, can be measured to sub-percent level, which enables a future test of the PMNS matrix unitarity to ~1% level and helps the forthcoming neutrinoless double beta decay experiments to constrain the allowed values. Combined with results from the next generation long-baseline beam neutrino and atmospheric neutrino oscillation experiments, the MH determination sensitivity can reach higher levels. In addition to the neutrino oscillation physics, MBRO detectors can also be utilized to study geoneutrinos, astrophysical neutrinos and proton decay. We propose to start a U.S. R&D program to identify, quantify and fulfill the key challenges essential for the success of MBRO experiments.

A. B. Balantekin; H. Band; R. Betts; J. J. Cherwinka; J. A. Detwiler; S. Dye; K. M. Heeger; R. Johnson; S. H. Kettell; K. Lau; J. G. Learned; C. J. Lin; J. J. Ling; B. Littlejohn; D. W. Liu; K. B. Luk; J. Maricic; K. McDonald; R. D. McKeown; J. Napolitano; J. C. Peng; X. Qian; N. Tolich; W. Wang; C. White; M. Yeh; C. Zhang; T. Zhao

2013-07-28T23:59:59.000Z

420

VERTICAL STRUCTURE OF NEUTRINO-DOMINATED ACCRETION DISKS AND NEUTRINO TRANSPORT IN THE DISKS  

SciTech Connect

We investigate the vertical structure of neutrino-dominated accretion disks by self-consistently considering the detailed microphysics, such as the neutrino transport, the vertical hydrostatic equilibrium, the conservation of lepton number, as well as the balance between neutrino cooling, advection cooling, and viscosity heating. After obtaining the emitting spectra of neutrinos and antineutrinos by solving the one-dimensional Boltzmann equation of neutrino and antineutrino transport in the disk, we calculate the neutrino/antineutrino luminosity and their annihilation luminosity. We find that the total neutrino and antineutrino luminosity is about 10{sup 54} erg s{sup -1} and their annihilation luminosity is about 5 Multiplication-Sign 10{sup 51} erg s{sup -1} with an extreme accretion rate 10 M{sub Sun} s{sup -1} and an alpha viscosity {alpha} = 0.1. In addition, we find that the annihilation luminosity is sensitive to the accretion rate and will not exceed 10{sup 50} erg s{sup -1}, which is not sufficient to power the fireball of most energetic gamma-ray bursts (GRBs) if the accretion rate is lower than 1 M{sub Sun} s{sup -1}. Therefore, the effects of the spin of the black hole or/and the magnetic field in the accretion flow might play a role in powering the central engine of GRBs.

Pan Zhen; Yuan Yefei, E-mail: yfyuan@ustc.edu.cn [Key Laboratory for Research in Galaxies and Cosmology CAS, Department of Astronomy, University of Science and Technology of China, Hefei, Anhui 230026 (China)

2012-11-10T23:59:59.000Z

Note: This page contains sample records for the topic "tau neutrinos heavy" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

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

E-Print Network (OSTI)

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 energy and position resolution. Both spherical gaseous and cylindrical liquid detectors are studied. Different source candidates are considered.

J. D. Vergados; Yu. N. Novikov

2010-06-19T23:59:59.000Z

422

Tau protein binds to microtubules through a flexible array of distributed weak sites. Z Cell Biol  

E-Print Network (OSTI)

Abstract. Tau protein plays a role in the extension and maintenance of neuronal processes through a direct association with microtubules. To characterize the nature of this association, we have synthesized a collection of tau protein fragments and studied their binding properties. The relatively weak affinity of tau protein for microtubules (ti10- ' M) is concentrated in a large region containing three or four 18 amino acid repeated binding elements. These are separated by apparently flexible but less conserved linker sequences of 13-14 amino acids that do not bind. Within the repeats, the binding energy for microtubules is delocalized and derives from a series of weak interactions contributed by small groups of amino acids. These unusual char acteristics suggest tau protein can assume multiple conformations and can pivot and perhaps migrate on the surface of the microtubule. The flexible structure of the tau protein binding interaction may allow it to be easily displaced from the microtubule lattice and may have important consequences for its function. TAU protein is a microtubule-associated protein present In brain and other neuronal tissues (Binder et al., 1985; Drubin et al., 1986; Weingarten et al., 1975). It is found in the axonal microtubules of mature neurons (Binder et al., 1985) and in the axonlike elongated neurite processes synthesized by differentiating neurons in culture

Karena Butner; Marc W. Kirschner

1991-01-01T23:59:59.000Z

423

Storage of ultracold neutrons in the UCN$\\tau$ magneto-gravitational trap  

E-Print Network (OSTI)

The UCN$\\tau$ experiment is designed to measure the lifetime $\\tau_{n}$ of the free neutron by trapping ultracold neutrons (UCN) in a magneto-gravitational trap. An asymmetric bowl-shaped NdFeB magnet Halbach array confines low-field-seeking UCN within the apparatus, and a set of electromagnetic coils in a toroidal geometry provide a background "holding" field to eliminate depolarization-induced UCN loss caused by magnetic field nodes. We present a measurement of the storage time $\\tau_{store}$ of the trap by storing UCN for various times, and counting the survivors. The data are consistent with a single exponential decay, and we find $\\tau_{store}=860\\pm19$ s: within $1 \\sigma$ of current global averages for $\\tau_{n}$. The storage time with the holding field deactiveated is found to be $\\tau_{store}=470 \\pm 160$ s; this decreased storage time is due to the loss of UCN which undergo Majorana spin-flips while being stored. We discuss plans to increase the statistical sensitivity of the measurement and investi...

Salvat, D J; Barlow, D; Broussard, L J; Bowman, J D; Callahan, N B; Clayton, S M; Cude-Woods, C; Currie, S; Dees, E B; Fox, W; Hickerson, K P; Holley, A T; Liu, C -Y; Makela, M; Medina, J; Morley, D J; Morris, C L; Penttila, S I; Ramsey, J; Saunders, A; Seestrom, S J; Sjue, S K L; Slaughter, B A; Sharapov, E I; Vanderwerp, J; VornDick, B; Walstrom, P L; Wang, Z; Womack, T L; Young, A R

2013-01-01T23:59:59.000Z

424

The US Long Baseline Neutrino Experiment Study  

Science Conference Proceedings (OSTI)

The US Long Baseline Neutrino Experiment Study was commissioned jointly by Brookhaven National Laboratory (BNL)and Fermi National Accelerator Laboratory (FNAL) to investigate the potential for future U.S. based long baseline neutrino oscillation experiments using MW class conventional neutrino beams that can be produced at FNAL. The experimental baselines are based on two possible detector locations: 1) off?axis to the existing FNAL NuMI beamline at baselines of 700 to 810 km and 2) NSF's proposed future Deep Underground Science and Engineering Laboratory (DUSEL) at baselines greater than 1000 km. Two detector technologies are considered: a megaton class Water Cherenkov detector deployed deep underground at a DUSEL site

Mary Bishai; US Long Baseline Study Group

2008-01-01T23:59:59.000Z

425

Detecting Solar Neutrino Flares and Flavors  

E-Print Network (OSTI)

Intense solar flares originated in sun spots produce high energy particles (protons, $\\alpha$) well observable by satellites and ground-based detectors. The flare onset produces signals in different energy bands (radio, X, gamma and neutrons). The most powerful solar flares as the ones occurred on 23 February 1956, 29 September 1989 and the more recent on October 28th, and the 2nd, 4th, 13th of November 2003 released in sharp times the largest flare energies (${E}_{FL} \\simeq {10}^{31}\\div {10}^{32} erg). The high energy solar flare protons scatter within the solar corona and they must be source of a prompt neutrino burst through the production of charged pions. Later on, solar flare particles hitting the atmosphere may marginally increase the atmospheric neutrino flux. The prompt solar neutrino flare may be detected in the largest underground $\

D. Fargion

2003-12-01T23:59:59.000Z

426

Discovering New Light States at Neutrino Experiments  

SciTech Connect

Experiments designed to measure neutrino oscillations also provide major opportunities for discovering very weakly coupled states. In order to produce neutrinos, experiments such as LSND collide thousands of Coulombs of protons into fixed targets, while MINOS and MiniBooNE also focus and then dump beams of muons. The neutrino detectors beyond these beam dumps are therefore an excellent arena in which to look for long-lived pseudoscalars or for vector bosons that kinetically mix with the photon. We show that these experiments have significant sensitivity beyond previous beam dumps, and are able to partially close the gap between laboratory experiments and supernovae constraints on pseudoscalars. Future upgrades to the NuMI beamline and Project X will lead to even greater opportunities for discovery. We also discuss thin target experiments with muon beams, such as those available in COMPASS, and show that they constitute a powerful probe for leptophilic PNGBs.

Essig, Rouven; /SLAC; Harnik, Roni; /Fermilab; Kaplan, Jared; /SLAC; Toro, Natalia; /Stanford U., Phys. Dept.

2011-08-11T23:59:59.000Z

427

Nuclear Propelled Vessels and Neutrino Oscillation Experiments  

E-Print Network (OSTI)

We study the effect of naval nuclear reactors on the study of neutrino oscillations. We find that the presence of naval reactors at unknown locations and times may limit the accuracy of future very long baseline reactor-based neutrino oscillation experiments. At the same time we argue that a nuclear powered surface ship such as a large Russian ice-breaker may provide an ideal source for precision experiments. While the relatively low reactor power would in this case require a larger detector, the source could be conveniently located at essentially any distance from a detector built at an underground location near a shore in a region of the world far away from other nuclear installations. The variable baseline would allow for a precise measurement of backgrounds and greatly reduced systematics from reactor flux and detector efficiency. In addition, once the oscillation measurement is completed, the detector could perform geological neutrino and astrophysical measurements with minimal reactor background.

J. Detwiler; G. Gratta; N. Tolich; Y. Uchida

2002-06-29T23:59:59.000Z

428

Solar Neutrino Measurement at SK-III  

E-Print Network (OSTI)

The full Super-Kamiokande-III data-taking period, which ran from August of 2006 through August of 2008, yielded 298 live days worth of solar neutrino data with a lower total energy threshold of 4.5 MeV. During this period we made many improvements to the experiment's hardware and software, with particular emphasis on its water purification system and Monte Carlo simulations. As a result of these efforts, we have significantly reduced the low energy backgrounds as compared to earlier periods of detector operation, cut the systematic errors by nearly a factor of two, and achieved a 4.5 MeV energy threshold for the solar neutrino analysis. In this presentation, I will present the preliminary SK-III solar neutrino measurement results.

The Super-Kamiokande Collaboration; :; B. S. Yang

2009-09-30T23:59:59.000Z

429

Probing Exotic Physics With Supernova Neutrinos  

Science Conference Proceedings (OSTI)

Future galactic supernovae will provide an extremely long baseline for studying the properties and interactions of neutrinos. In this paper, we discuss the possibility of using such an event to constrain (or discover) the effects of exotic physics in scenarios that are not currently constrained and are not accessible with reactor or solar neutrino experiments. In particular, we focus on the cases of neutrino decay and quantum decoherence. We calculate the expected signal from a core-collapse supernova in both current and future water Cerenkov, scintillating, and liquid argon detectors, and find that such observations will be capable of distinguishing between many of these scenarios. Additionally, future detectors will be capable of making strong, model-independent conclusions by examining events associated with a galactic supernova's neutronization burst.

Kelso, Chris; Hooper, Dan

2010-09-01T23:59:59.000Z

430

NEUTRINO PROCESSES IN PARTIALLY DEGENERATE NEUTRON MATTER  

Science Conference Proceedings (OSTI)

We investigate neutrino processes for conditions reached in simulations of core-collapse supernovae. In regions where neutrino-matter interactions play an important role, matter is partially degenerate, and we extend earlier work that addressed the degenerate regime. We derive expressions for the spin structure factor in neutron matter, which is a key quantity required for evaluating rates of neutrino processes. We show that, for essentially all conditions encountered in the post-bounce phase of core-collapse supernovae, it is a very good approximation to calculate the spin relaxation rates in the nondegenerate limit. We calculate spin relaxation rates based on chiral effective field theory interactions and find that they are typically a factor of two smaller than those obtained using the standard one-pion-exchange interaction alone.

Bacca, S.; Hally, K. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V6T 2A3 (Canada); Liebendoerfer, M.; Perego, A. [Department of Physics, University of Basel, Klingelbergstr. 82, 4056 Basel (Switzerland); Pethick, C. J. [Niels Bohr International Academy, Niels Bohr Institute, Blegdamsvej 17, DK-2100 Copenhagen O (Denmark); Schwenk, A. [ExtreMe Matter Institute EMMI, GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, D-64291 Darmstadt (Germany)

2012-10-10T23:59:59.000Z

431

Countintg Extra Dimensions: Magnetic Cherenkov Radiation from High Energy Neutrinos  

E-Print Network (OSTI)

In theories which require a space of dimension d>4, there is a natural mechanism of suppressing neutrino masses: while Standard Model fields are confined to a 3-brane, right handed neutrinos live in the bulk. Due to Kaluza-Klein excitations, the effective magnetic moments of neutrinos are enhanced. The effective magnetic moment is a monotonically growing function of the energy of the neutrino: consequently, high energy neutrinos can emit observable amounts of magnetic Cherenkov radiation. By observing the energy dependence of the magnetic Cherenkov radiation, one may be able to determine the number of compactified dimensions.

G. Domokos; Andrea Erdas; S. Kovesi-Domokos

2002-12-30T23:59:59.000Z

432

Report of the Solar and Atmospheric Neutrino Working Group  

SciTech Connect

The highest priority of the Solar and Atmospheric Neutrino Experiment Working Group is the development of a real-time, precision experiment that measures the pp solar neutrino flux. A measurement of the pp solar neutrino flux, in comparison with the existing precision measurements of the high energy {sup 8}B neutrino flux, will demonstrate the transition between vacuum and matter-dominated oscillations, thereby quantitatively testing a fundamental prediction of the standard scenario of neutrino flavor transformation. The initial solar neutrino beam is pure {nu}{sub e}, which also permits sensitive tests for sterile neutrinos. The pp experiment will also permit a significantly improved determination of {theta}{sub 12} and, together with other solar neutrino measurements, either a measurement of {theta}{sub 13} or a constraint a factor of two lower than existing bounds. In combination with the essential pre-requisite experiments that will measure the {sup 7}Be solar neutrino flux with a precision of 5%, a measurement of the pp solar neutrino flux will constitute a sensitive test for non-standard energy generation mechanisms within the Sun. The Standard Solar Model predicts that the pp and {sup 7}Be neutrinos together constitute more than 98% of the solar neutrino flux. The comparison of the solar luminosity measured via neutrinos to that measured via photons will test for any unknown energy generation mechanisms within the nearest star. A precise measurement of the pp neutrino flux (predicted to be 92% of the total flux) will also test stringently the theory of stellar evolution since the Standard Solar Model predicts the pp flux with a theoretical uncertainty of 1%. We also find that an atmospheric neutrino experiment capable of resolving the mass hierarchy is a high priority. Atmospheric neutrino experiments may be the only alternative to very long baseline accelerator experiments as a way of resolving this fundamental question. Such an experiment could be a very large scale water Cerenkov detector, or a magnetized detector with flavor and antiflavor sensitivity. Additional priorities are nuclear physics measurements which will reduce the uncertainties in the predictions of the Standard Solar Model, and similar supporting measurements for atmospheric neutrinos (cosmic ray fluxes, magnetic fields, etc.). We note as well that the detectors for both solar and atmospheric neutrino measurements can serve as multipurpose detectors, with capabilities of discovering dark matter, relic supernova neutrinos, proton decay, or as targets for long baseline accelerator neutrino experiments.

Back, H.; Bahcall, J.N.; Bernabeu, J.; Boulay, M.G.; Bowles, T.; Calaprice, F.; Champagne, A.; Freedman, S.; Gai, M.; Galbiati, C.; Gallagher, H.; Gonzalez-Garcia, C.; Hahn, R.L.; Heeger, K.M.; Hime, A.; Jung, C.K.; Klein, J.R.; Koike, M.; Lanou, R.; Learned, J.G.; Lesko, K.T.; Losecco, J.; Maltoni, M.; Mann, A.; McKinsey, D.; Palomares-Ruiz, S.; Pena-Garay, C.; Petcov, S.T.; Piepke, A.; Pitt, M.; Raghavan, R.; Robertson, R.G.H.; Scholberg, K.; Sobel, H.W.; Takeuchi, T.; Vogelaar, R.; Wolfenstein, L.

2004-10-22T23:59:59.000Z

433

Could One Find Petroleum Using Neutrino Oscillations in Matter?  

E-Print Network (OSTI)

In neutrino physics, it is now widely believed that neutrino oscillations are influenced by the presence of matter, modifying the energy spectrum produced by a neutrino beam traversing the Earth. Here, we will discuss the reverse problem, i.e. what could be learned about the Earth's interior from a single neutrino baseline energy spectrum, especially about the Earth's mantle. We will use a statistical analysis with a low-energy neutrino beam under very optimistic assumptions. At the end, we will note that it is hard to find petroleum with such a method, though it is not too far away from technical feasibility.

Tommy Ohlsson; Walter Winter

2001-11-20T23:59:59.000Z

434

Search for charged Higgs bosons decaying via H+ -> tau nu in top quark pair events using pp collision data at sqrt(s) = 7 TeV with the ATLAS detector  

Science Conference Proceedings (OSTI)

The results of a search for charged Higgs bosons are presented. The analysis is based on 4.6 fb{sup -1} of proton-proton collision data at {radical}s = 7 TeV collected by the ATLAS experiment at the Large Hadron Collider, using top quark pair events with a {tau} lepton in the final state. The data are consistent with the expected background from Standard Model processes. Assuming that the branching ratio of the charged Higgs boson to a {tau} lepton and a neutrino is 100%, this leads to upper limits on the branching ratio of top quark decays to a b quark and a charged Higgs boson between 5% and 1% for charged Higgs boson masses ranging from 90 GeV to 160 GeV, respectively. In the context of the m{sub h}{sup max} scenario of the MSSM, tan {beta} above 12-26, as well as between 1 and 2-6, can be excluded for charged Higgs boson masses between 90 GeV and 150 GeV.

Aad, Georges; Abbott, Brad; Abdallah, Jalal; Abdel Khalek, Samah; Abdelalim, Ahmed Ali; Abdinov, Ovsat; Abi, Babak; Abolins, Maris; AbouZeid, Ossama; Abramowicz, Halina; Abreu, Henso; /SUNY, Albany /Alberta U. /Ankara U. /Dumlupinar U. /Gazi U. /TOBB ETU, Ankara /TAEK, Ankara /Annecy, LAPP /Argonne /Arizona U. /Texas U., Arlington

2012-04-01T23:59:59.000Z

435

Planetary influence on the young Sun's evolution: the solar neutrino probe  

E-Print Network (OSTI)

Recent observations of solar twin stars with planetary systems like the Sun, have uncovered that these present a peculiar surface chemical composition. This is believed to be related to the formation of earth-like planets. This suggests that twin stars have a radiative interior that is richer in heavy elements than their envelopes. Moreover, the current standard solar model does not fully agree with the helioseismology data and solar neutrino flux measurements. In this work, we find that this agreement can improve if the Sun has mass loss during the pre-main sequence, as was previously shown by other groups. Despite this better agreement, the internal composition of the Sun is still uncertain, especially for elements heavier than helium. With the goal of inferring the chemical abundance of the solar interior, we tested several chemical compositions. We found that heavy element abundances influence the sound speed and solar neutrinos equally. Nevertheless, the carbon-nitrogen-oxygen (CNO;13N, 15O and 17F) neut...

Lopes, Ilidio

2013-01-01T23:59:59.000Z

436

Neutrino Event Rates from Gamma Ray Bursts  

E-Print Network (OSTI)

We recalculate the diffuse flux of high energy neutrinos produced by Gamma Ray Bursts (GRB) in the relativistic fireball model. Although we confirm that the average single burst produces only ~10^{-2} high energy neutrino events in a detector with 1 km^2 effective area, i.e. about 10 events per year, we show that the observed rate is dominated by burst-to-burst fluctuations which are very large. We find event rates that are expected to be larger by one order of magnitude, likely more, which are dominated by a few very bright bursts. This greatly simplifies their detection.

F. Halzen; D. W. Hooper

1999-08-12T23:59:59.000Z

437

Oscillation Solutions to Solar Neutrino Problem  

E-Print Network (OSTI)

The current status of oscillation solutions to the Solar Neutrino Problem is reviewed. Four oscillation solutions are discussed in the light of 708d Superkamiokande data: MSW, Just-So VO, VO with Energy-Independent Suppression (EIS) and Resonant-Spin-Flavor-Precession (RSFP). Only EIS VO is strongly disfavoured by the global rates, mostly due to the Homestake data. Vacuum oscillations give an interesting solution which explains high-energy excess of events observed by Superkamiokande and predicts {\\em semi-annual} seasonal variation of $Be$-neutrino flux. There are indications to these variations in the GALLEX and Homestake data. No direct evidence for oscillation is found yet.

V. Berezinsky

1999-04-07T23:59:59.000Z

438

Oscillation solutions to solar neutrino problem  

E-Print Network (OSTI)

The current status of oscillation solutions to the Solar Neutrino Problem is reviewed. Four oscillation solutions are discussed in the light of 708d Superkamiokande data: MSW, Just-So VO, VO with Energy-Independent Suppression (EIS) and Resonant-Spin-Flavor-Precession (RSFP). Only EIS VO is strongly disfavoured by the global rates, mostly due to the Homestake data. Vacuum oscillations give an interesting solution which explains high-energy excess of events observed by Superkamiokande and predicts {\\em semi-annual} seasonal variation of $Be$-neutrino flux. There are indications to these variations in the GALLEX and Homestake data. No direct evidence for oscillation is found yet.

Berezinsky, Veniamin Sergeevich

2000-01-01T23:59:59.000Z

439

Neutrino absortion cross sections in supernova environment  

E-Print Network (OSTI)

We study charged-current neutrino cross sections on neutronrich nuclei in the mass $A\\sim60$ region. Special attention is paid to environmental effects, i.e. finite temperature and density, on the cross sections. As these effects are largest for small neutrino energies, it is sufficient to study only the Gamow-Teller (GT) contributions to the cross sections. The relevant GT strength distributions are derived from large-scale shell model calculations. We find that the low-energy cross sections are enhanced at finite temperatures. However, for $(\

J. M. Sampaio; K. Langanke; G. Martinez-Pinedo

2001-04-04T23:59:59.000Z

440

Neutrinoless double beta decay and neutrino masses  

SciTech Connect

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

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

2012-07-27T23:59:59.000Z

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441

The Daya Bay Reactor Neutrino Experiment Sees Evidence that Electron  

NLE Websites -- All DOE Office Websites (Extended Search)

Science Highlights » 2013 Science Highlights » 2013 » The Daya Bay Reactor Neutrino Experiment Sees Evidence that Electron Neutrinos Turn into Muon Neutrinos High Energy Physics (HEP) HEP Home About Research Facilities Science Highlights Benefits of HEP Funding Opportunities Advisory Committees News & Resources Contact Information High Energy Physics U.S. Department of Energy SC-25/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3624 F: (301) 903-2597 E: sc.hep@science.doe.gov More Information » June 2013 The Daya Bay Reactor Neutrino Experiment Sees Evidence that Electron Neutrinos Turn into Muon Neutrinos Surprisingly large effect greatly increases the probability that new neutrino experiments will be able to see the differences between matter and

442

SNIF: A Futuristic Neutrino Probe for Undeclared Nuclear Fission Reactors  

E-Print Network (OSTI)

Today reactor neutrino experiments are at the cutting edge of fundamental research in particle physics. Understanding the neutrino is far from complete, but thanks to the impressive progress in this field over the last 15 years, a few research groups are seriously considering that neutrinos could be useful for society. The International Atomic Energy Agency (IAEA) works with its Member States to promote safe, secure and peaceful nuclear technologies. In a context of international tension and nuclear renaissance, neutrino detectors could help IAEA to enforce the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). In this article we discuss a futuristic neutrino application to detect and localize an undeclared nuclear reactor from across borders. The SNIF (Secret Neutrino Interactions Finder) concept proposes to use a few hundred thousand tons neutrino detectors to unveil clandestine fission reactors. Beyond previous studies we provide estimates of all known background sources as a function of the detecto...

Lasserre, Thierry; Mention, Guillaume; Reboulleau, Romain; Cribier, Michel; Letourneau, Alain; Lhuillier, David

2010-01-01T23:59:59.000Z

443

FEASIBILITY STUDY II OF A MUON BASED NEUTRINO SOURCE.  

SciTech Connect

The concept of using a muon storage ring to provide a well characterized beam of muon and electron neutrinos (a Neutrino Factory) has been under study for a number of years now at various laboratories throughout the world. The physics program of a Neutrino Factoryis focused on the relatively unexplored neutrino sector. In conjunction with a detector located a suitable distance from the neutrino source, the facility would make valuable contributions to the study of neutrino masses and lepton mixing. A Neutrino Factory is expected to improve the measurement accuracy of sin{sup 2}(2{theta}{sub 23}) and {Delta}m{sup 2}{sub 32} and provide measurements of sin{sup 2}(2{theta}{sub 13}) and the sign of {Delta}m{sup 2}{sub 32}. It may also be able to measure CP violation in the lepton sector.

GALLARDO,J.C.; OZAKI,S.; PALMER,R.B.; ZISMAN,M.

2001-06-30T23:59:59.000Z

444

Detecting neutrinos from black hole-neutron star mergers  

Science Conference Proceedings (OSTI)

While it is well known that neutrinos are emitted from standard core collapse protoneutron star supernovae, less attention has been focused on neutrinos from accretion disks. These disks occur in some supernovae (i.e. collapsars) as well as in compact object mergers, and they emit neutrinos with similar properties to those from protoneutron star supernovae. These disks and their neutrinos play an important role in our understanding of gamma ray bursts as well as the nucleosynthesis they produce. We study a disk that forms in the merger of a black hole and a neutron star and examine the neutrino fluxes, luminosities and neutrino surfaces for the disk. We also estimate the number of events that would be registered in current and proposed supernova neutrino detectors if such an event were to occur in the Galaxy.

Caballero, O. L.; McLaughlin, G. C.; Surman, R. [Department of Physics, North Carolina State University, Raleigh, North Carolina 27695 (United States); Department of Physics and Astronomy, Union College, Schenectady, New York 12308 (United States)

2009-12-15T23:59:59.000Z

445

Detecting neutrinos from black hole neutron stars mergers  

E-Print Network (OSTI)

While it is well known that neutrinos are emitted from standard core collapse protoneutron star supernovae, less attention has been focused on neutrinos from accretion disks. These disks occur in some supernovae (i.e. "collapsars") as well as in compact object mergers, and they emit neutrinos with similar properties to those from protoneutron star supernovae. These disks and their neutrinos play an important role in our understanding of gamma ray bursts as well as the nucleosynthesis they produce. We study a disk that forms in the merger of a black hole and a neutron star and examine the neutrino fluxes, luminosities and neutrino surfaces for the disk. We also estimate the number of events that would be registered in current and proposed supernova neutrino detectors if such an event were to occur in the Galaxy.

O. L. Caballero; G. C. McLaughlin; R. Surman

2009-10-08T23:59:59.000Z

446

Testing Mass Varying Neutrino With Short Gamma Ray Burst  

E-Print Network (OSTI)

In this paper we study the possibility of probing for the absolute neutrino mass and its variation with short Gamma Ray Burst (GRB). We have calculated the flight time difference between a massive neutrino and a photon in two different approaches to mass varying neutrinos. Firstly we parametrize the neutrino mass as a function of redshift in a model independent way, then we consider two specific models where the neutrino mass varies during the evolution of the Quintessence fields. Our calculations show in general the value of the time delay is changed substantially relative to a constant neutrino mass. Furthermore our numerical results show that the flight time delay in these models is expected to be larger than the duration time of the short GRB, which opens a possibility of testing the scenario of mass varying neutrino with the short GRB.

Hong Li; Zigao Dai; Xinmin Zhang

2004-11-17T23:59:59.000Z

447

Ultra high energy neutrino-nucleon cross section from cosmic ray experiments and neutrino telescopes  

E-Print Network (OSTI)

We deduce the cosmogenic neutrino flux by jointly analysing ultra high energy cosmic ray data from HiRes-I and II, AGASA and the Pierre Auger Observatory. We make two determinations of the neutrino flux by using a model-dependent method and a model-independent method. The former is well-known, and involves the use of a power-law injection spectrum. The latter is a regularized unfolding procedure. We then use neutrino flux bounds obtained by the RICE experiment to constrain the neutrino-nucleon inelastic cross section at energies inaccessible at colliders. The cross section bounds obtained using the cosmogenic fluxes derived by unfolding are the most model-independent bounds to date.

V. Barger; Patrick Huber; Danny Marfatia

2006-06-29T23:59:59.000Z

448

Search for muon neutrinos from Gamma-Ray Bursts with the IceCube neutrino telescope  

E-Print Network (OSTI)

2009, GCN: The Gamma ray bursts Coordinates Network, http://for muon neutrinos from Gamma-Ray Bursts with the IceCubeMereghetti, S. 2004, in Gamma-ray Bursts: 30 Years of

Abbasi, R.

2010-01-01T23:59:59.000Z

449

Addendum: The SNO Solar Neutrino Data, Neutrinoless Double Beta-Decay and Neutrino Mass Spectrum  

E-Print Network (OSTI)

We update our earlier study in [1], which was inspired by the 2002 SNO data, on the implications of the results of the solar neutrino experiments for the predictions of the effective Majorana mass in neutrinoless double beta-decay, ||. We obtain predictions for || using the values of the neutrino oscillation parameters, obtained in the analyzes of the presently available solar neutrino data, including the just published data from the salt phase of the SNO experiment, the atmospheric neu