WorldWideScience

Sample records for relic neutrino abundance

  1. Dark matter relic abundance and light sterile neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Yi-Lei [Center for High Energy Physics,Peking University, Beijing 100871 (China); Zhu, Shou-hua [Center for High Energy Physics,Peking University, Beijing 100871 (China); Institute of Theoretical Physics & State Key Laboratory of Nuclear Physics and Technology,Peking University, Beijing 100871 (China); Collaborative Innovation Center of Quantum Matter,Beijing 100871 (China)

    2017-01-09

    In this paper, we calculate the relic abundance of the dark matter particles when they can annihilate into sterile neutrinos with the mass ≲100 GeV in a simple model. Unlike the usual standard calculations, the sterile neutrino may fall out of the thermal equilibrium with the thermal bath before the dark matter freezes out. In such a case, if the Yukawa coupling y{sub N} between the Higgs and the sterile neutrino is small, this process gives rise to a larger Ω{sub DM}h{sup 2} so we need a larger coupling between the dark matter and the sterile neutrino for a correct relic abundance.

  2. The physics of relic neutrinos

    International Nuclear Information System (INIS)

    Dighe, A.; Pastor, S.; Smirnov, A.

    1998-12-01

    We report on the main results presented at the workshop on the Physics of Relic Neutrinos. The study of relic neutrinos involves a broad spectrum of problems in particle physics, astrophysics and cosmology. Features of baryogenesis and leptogenesis could be imprinted in the properties of the relic neutrino sea. Relic neutrinos played a crucial role in the big bang nucleosynthesis. Being the hot component of the dark matter, they have participated in the structure formation in the universe. Although the direct detection of the sea seems impossible at this stage, there could be various indirect manifestations of these neutrinos which would allow us to study the properties of the sea both in the past and at the present epoch. (author)

  3. Prospects for relic neutrino detection

    International Nuclear Information System (INIS)

    Smith, P.F.

    1991-03-01

    The standard big bang model predicts a universal background of relic neutrinos, comparable in number density to the background microwave photons. This neutrino background is undetectable at the present time firstly because the neutrino energy is very low (10 -4 -10 -5 eV) resulting in a very low energy transfer to any conceivable detector, and secondly the low energy gives a lower interaction cross section and hence a very low event rate per unit mass. These obstacles have so far precluded any realistic proposal for relic neutrino detection. The aim of this paper is to illustrate the difficulties in detecting these neutrinos by summarizing six detection ideas which have been previously considered, indicating in each case the problems which have prevented the idea being developed into an experimental proposal. The most promising direction for further study would appear to be that of coherent interactions. So far, no investigations of this idea have resulted in a practical detection scheme, but in this paper one new variation is suggested which could in principle give an observable effect, if the necessary stringent experimental conditions could be created. It is suggested that this may become possible with the aid of foreseeable 21st century developments in nanotechnology. (author)

  4. Relic neutrino asymmetry evolution from first principles

    International Nuclear Information System (INIS)

    Bell, N.F.; Volkas, R.R.; Wong, Y.Y.Y.

    1998-09-01

    The exact Quantum Kinetic Equations for a two-flavour active-sterile neutrino system are used to provide a systematic derivation of approximate evolution equations for the relic neutrino asymmetry. An extension of the adiabatic approximation for matter-affected neutrino oscillations is developed which incorporates decoherence due to collisions. Exact and approximate expressions for the decoherence and repopulation functions are discussed. A first pass is made over the exact treatment of multi-flavour partially incoherent oscillations. (authors)

  5. Neutrino Coannihilation on Dark-Matter Relics?

    Energy Technology Data Exchange (ETDEWEB)

    Barenboim, Gabriela; /Valencia U.; Mena Requejo, Olga; Quigg, Chris; /Fermilab

    2006-04-01

    High-energy neutrinos may resonate with relic background neutralinos to form short-lived sneutrinos. In some circumstances, the decay chain that leads back to the lightest supersymmetric particle would yield few-GeV gamma rays or charged-particle signals. Although resonant coannihilation would occur at an appreciable rate in our galaxy, the signal in any foreseeable detector is unobservably small.

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

    International Nuclear Information System (INIS)

    Volpe, C.; Welzel, J.

    2007-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-07-01

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

  8. Calculation of the local density of relic neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    De Salas, P.F.; Gariazzo, S.; Pastor, S. [Instituto de Física Corpuscular (CSIC-Universitat de València), Parc Científic UV, C/ Catedrático José Beltrán, 2, E-46980 Paterna (Valencia) (Spain); Lesgourgues, J., E-mail: pabferde@ific.uv.es, E-mail: gariazzo@ific.uv.es, E-mail: Julien.Lesgourgues@physik.rwth-aachen.de, E-mail: pastor@ific.uv.es [Institute for Theoretical Particle Physics and Cosmology (TTK), RWTH Aachen University, D-52056 Aachen (Germany)

    2017-09-01

    Nonzero neutrino masses are required by the existence of flavour oscillations, with values of the order of at least 50 meV . We consider the gravitational clustering of relic neutrinos within the Milky Way, and used the N -one-body simulation technique to compute their density enhancement factor in the neighbourhood of the Earth with respect to the average cosmic density. Compared to previous similar studies, we pushed the simulation down to smaller neutrino masses, and included an improved treatment of the baryonic and dark matter distributions in the Milky Way. Our results are important for future experiments aiming at detecting the cosmic neutrino background, such as the Princeton Tritium Observatory for Light, Early-universe, Massive-neutrino Yield (PTOLEMY) proposal. We calculate the impact of neutrino clustering in the Milky Way on the expected event rate for a PTOLEMY-like experiment. We find that the effect of clustering remains negligible for the minimal normal hierarchy scenario, while it enhances the event rate by 10 to 20% (resp. a factor 1.7 to 2.5) for the minimal inverted hierarchy scenario (resp. a degenerate scenario with 150 meV masses). Finally we compute the impact on the event rate of a possible fourth sterile neutrino with a mass of 1.3 eV.

  9. Relic abundance of WIMPs in non-standard cosmological scenarios

    International Nuclear Information System (INIS)

    Yimingniyazi, W.

    2007-01-01

    In this thesis we study the relic density n χ of non--relativistic long--lived or stable particles χ in various non--standard cosmological scenarios. First, we discuss the relic density in the non--standard cosmological scenario in which the temperature is too low for the particles χ to achieve full chemical equilibrium. We also investigated the case where χ particles are non--thermally produced from the decay of heavier particles in addition to the usual thermal production. In low temperature scenario, we calculate the relic abundance starting from arbitrary initial temperatures T 0 of the radiation--dominated epoch and derive approximate solutions for the temperature dependence of the relic density which can accurately reproduces numerical results when full thermal equilibrium is not achieved. If full equilibrium is reached, our ansatz no longer reproduces the correct temperature dependence of the χ number density. However, we can contrive a semi-analytic formula which gives the correct final relic density, to an accuracy of about 3% or better, for all cross sections and initial temperatures. We also derive the lower bound on the initial temperature T 0 , assuming that the relic particle accounts for the dark matter energy density in the universe. The observed cold dark matter abundance constrains the initial temperature T 0 ≥m χ /23, where m χ is the mass of χ. Second, we discuss the χ density in the scenario where the the Hubble parameter is modified. Even in this case, an approximate formula similar to the standard one is found to be capable of predicting the final relic abundance correctly. Choosing the χ annihilation cross section such that the observed cold dark matter abundance is reproduced in standard cosmology, we constrain possible modifications of the expansion rate at T ∝m χ /20, well before Big Bang Nucleosynthesis. (orig.)

  10. Relic abundance of WIMPs in non-standard cosmological scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Yimingniyazi, W.

    2007-08-06

    In this thesis we study the relic density n{sub {chi}} of non--relativistic long--lived or stable particles {chi} in various non--standard cosmological scenarios. First, we discuss the relic density in the non--standard cosmological scenario in which the temperature is too low for the particles {chi} to achieve full chemical equilibrium. We also investigated the case where {chi} particles are non--thermally produced from the decay of heavier particles in addition to the usual thermal production. In low temperature scenario, we calculate the relic abundance starting from arbitrary initial temperatures T{sub 0} of the radiation--dominated epoch and derive approximate solutions for the temperature dependence of the relic density which can accurately reproduces numerical results when full thermal equilibrium is not achieved. If full equilibrium is reached, our ansatz no longer reproduces the correct temperature dependence of the {chi} number density. However, we can contrive a semi-analytic formula which gives the correct final relic density, to an accuracy of about 3% or better, for all cross sections and initial temperatures. We also derive the lower bound on the initial temperature T{sub 0}, assuming that the relic particle accounts for the dark matter energy density in the universe. The observed cold dark matter abundance constrains the initial temperature T{sub 0} {>=}m{sub {chi}}/23, where m{sub {chi}} is the mass of {chi}. Second, we discuss the {chi} density in the scenario where the the Hubble parameter is modified. Even in this case, an approximate formula similar to the standard one is found to be capable of predicting the final relic abundance correctly. Choosing the {chi} annihilation cross section such that the observed cold dark matter abundance is reproduced in standard cosmology, we constrain possible modifications of the expansion rate at T {proportional_to}m{sub {chi}}/20, well before Big Bang Nucleosynthesis. (orig.)

  11. Relic abundance of mass-varying cold dark matter particles

    International Nuclear Information System (INIS)

    Rosenfeld, Rogerio

    2005-01-01

    In models of coupled dark energy and dark matter the mass of the dark matter particle depends on the cosmological evolution of the dark energy field. In this Letter we exemplify in a simple model the effects of this mass variation on the relic abundance of cold dark matter

  12. Relic right-handed Dirac neutrinos and implications for detection of cosmic neutrino background

    Directory of Open Access Journals (Sweden)

    Jue Zhang

    2016-02-01

    Full Text Available It remains to be determined experimentally if massive neutrinos are Majorana or Dirac particles. In this connection, it has been recently suggested that the detection of cosmic neutrino background of left-handed neutrinos νL and right-handed antineutrinos ν‾R in future experiments of neutrino capture on beta-decaying nuclei (e.g., νe+H3→He3+e− for the PTOLEMY experiment is likely to distinguish between Majorana and Dirac neutrinos, since the capture rate is twice larger in the former case. In this paper, we investigate the possible impact of right-handed neutrinos on the capture rate, assuming that massive neutrinos are Dirac particles and both right-handed neutrinos νR and left-handed antineutrinos ν‾L can be efficiently produced in the early Universe. It turns out that the capture rate can be enhanced at most by 28% due to the presence of relic νR and ν‾L with a total number density of 95 cm−3, which should be compared to the number density 336 cm−3 of cosmic neutrino background. The enhancement has actually been limited by the latest cosmological and astrophysical bounds on the effective number of neutrino generations Neff=3.14−0.43+0.44 at the 95% confidence level. For illustration, two possible scenarios have been proposed for thermal production of right-handed neutrinos in the early Universe.

  13. PeV IceCube signals and Dark Matter relic abundance in modified cosmologies

    Science.gov (United States)

    Lambiase, G.; Mohanty, S.; Stabile, An.

    2018-04-01

    The discovery by the IceCube experiment of a high-energy astrophysical neutrino flux with energies of the order of PeV, has opened new scenarios in astroparticles physics. A possibility to explain this phenomenon is to consider the minimal models of Dark Matter (DM) decay, the 4-dimensional operator ˜ y_{α χ }\\overline{{L_{L_{α }}}} H χ , which is also able to generate the correct abundance of DM in the Universe. Assuming that the cosmological background evolves according to the standard cosmological model, it follows that the rate of DM decay Γ _χ ˜ |y_{α χ }|^2 needed to get the correct DM relic abundance (Γ _χ ˜ 10^{-58}) differs by many orders of magnitude with respect that one needed to explain the IceCube data (Γ _χ ˜ 10^{-25}), making the four-dimensional operator unsuitable. In this paper we show that assuming that the early Universe evolution is governed by a modified cosmology, the discrepancy between the two the DM decay rates can be reconciled, and both the IceCube neutrino rate and relic density can be explained in a minimal model.

  14. Effects of QCD bound states on dark matter relic abundance

    Energy Technology Data Exchange (ETDEWEB)

    Liew, Seng Pei [Department of Physics, The University of Tokyo,Bunkyo-ku, Tokyo 113-0033 (Japan); Luo, Feng [Kavli IPMU (WPI), UTIAS, The University of Tokyo,Kashiwa, Chiba 277-8583 (Japan)

    2017-02-17

    We study scenarios where there exists an exotic massive particle charged under QCD in the early Universe. We calculate the formation and dissociation rates of bound states formed by pairs of these particles, and apply the results in dark matter (DM) coannihilation scenarios, including also the Sommerfeld effect. We find that on top of the Sommerfeld enhancement, bound-state effects can further significantly increase the largest possible DM masses which can give the observed DM relic abundance, by ∼30–100% with respect to values obtained by considering the Sommerfeld effect only, for the color triplet or octet exotic particles we consider. In particular, it indicates that the Bino DM mass in the right-handed stop-Bino coannihilation scenario in the Minimal Supersymmetric extension of the Standard Model (MSSM) can reach ∼2.5 TeV, even though the potential between the stop and antistop prior to forming a bound state is repulsive. We also apply the bound-state effects in the calculations of relic abundance of long-lived or metastable massive colored particles, and discuss the implications on the BBN constraints and the abundance of a super-weakly interacting DM. The corrections for the bound-state effect when the exotic massive colored particles also carry electric charges, and the collider bounds are also discussed.

  15. Big-bang nucleosynthesis and the relic abundance of dark matter in a stau-neutralino coannihilation scenario

    International Nuclear Information System (INIS)

    Jittoh, Toshifumi; Koike, Masafumi; Sato, Joe; Yamanaka, Masato; Kohri, Kazunori; Shimomura, Takashi

    2008-01-01

    A scenario of the big-bang nucleosynthesis is analyzed within the minimal supersymmetric standard model, which is consistent with a stau-neutralino coannihilation scenario to explain the relic abundance of dark matter. We find that we can account for the possible discrepancy of the abundance of 7 Li between the observation and the prediction of the big-bang nucleosynthesis by taking the mass of the neutralino as 300 GeV and the mass difference between the stau and the neutralino as (100-120) MeV. We can therefore simultaneously explain the abundance of the dark matter and that of 7 Li by these values of parameters. The lifetime of staus in this scenario is predicted to be O(100-1000) sec.

  16. From direct detection to relic abundance: the case of proton-philic spin-dependent inelastic Dark Matter

    Energy Technology Data Exchange (ETDEWEB)

    Scopel, Stefano; Yu, Hyeonhye, E-mail: scopel@sogang.ac.kr, E-mail: skyh2yu@gmail.com [Department of Physics, Sogang University, Seoul (Korea, Republic of)

    2017-04-01

    We discuss strategies to make inferences on the thermal relic abundance of a Weakly Interacting Massive Particle (WIMP) when the same effective dimension-six operator that explains an experimental excess in direct detection is assumed to drive decoupling at freeze-out, and apply them to the explicit scenario of WIMP inelastic up-scattering with spin-dependent couplings to protons (proton-philic Spin-dependent Inelastic Dark Matter, pSIDM), a phenomenological set-up containing two Dark Matter (DM) particles χ{sub 1} and χ{sub 2} with masses m {sub χ}= m {sub χ{sub 1}} and m {sub χ{sub 2}}= m {sub χ}+δ that we have shown in a previous paper to explain the DAMA effect in compliance with the constraints from other detectors. We also update experimental constraints on pSIDM, extend the analysis to the most general spin-dependent momentum-dependent interactions allowed by non-relativistic Effective Field Theory (EFT), and consider for the WIMP velocity distribution in our Galaxy f ( v ) both a halo-independent approach and a standard Maxwellian. Under these conditions we find that the DAMA effect can be explained in terms of the particle χ{sub 1} in compliance with all the other constraints for all the analyzed EFT couplings and also for a Maxwellian f ( v ). As far as the relic abundance is concerned, we show that the problem of calculating it by using direct detection data to fix the model parameters is affected by a strong sensitivity on f ( v ) and by the degeneracy between the WIMP local density ρ{sub χ} and the WIMP-nucleon scattering cross section, since ρ{sub χ} must be rescaled with respect to the observed DM density in the neighborhood of the Sun when the calculated relic density Ω is smaller than the observed one Ω{sub 0}. As a consequence, a DM direct detection experiment is not directly sensitive to the physical cut-off scale of the EFT, but on some dimensional combination that does not depend on the actual value of Ω. However, such degeneracy

  17. Relaxing neutrino mass bounds by a running cosmological constant

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, F.; Schrempp, L.

    2007-11-15

    We establish an indirect link between relic neutrinos and the dark energy sector which originates from the vacuum energy contributions of the neutrino quantum fields. Via renormalization group effects they induce a running of the cosmological constant with time which dynamically influences the evolution of the cosmic neutrino background. We demonstrate that the resulting reduction of the relic neutrino abundance allows to largely evade current cosmological neutrino mass bounds and discuss how the scenario might be probed by the help of future large scale structure surveys and Planck data. (orig.)

  18. Relaxing neutrino mass bounds by a running cosmological constant

    International Nuclear Information System (INIS)

    Bauer, F.; Schrempp, L.

    2007-11-01

    We establish an indirect link between relic neutrinos and the dark energy sector which originates from the vacuum energy contributions of the neutrino quantum fields. Via renormalization group effects they induce a running of the cosmological constant with time which dynamically influences the evolution of the cosmic neutrino background. We demonstrate that the resulting reduction of the relic neutrino abundance allows to largely evade current cosmological neutrino mass bounds and discuss how the scenario might be probed by the help of future large scale structure surveys and Planck data. (orig.)

  19. Neutrino statistics: elementary problems and some applications

    Energy Technology Data Exchange (ETDEWEB)

    Kuchowicz, B

    1973-01-01

    The treatment of neutrinos includes neutrinos in statistical equilibrium, mathematical refinements, application to stars, the relic neutrinos in cosmology, and some unsolved problems and prospects. (JFP)

  20. Cosmological and supernova neutrinos

    Science.gov (United States)

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

    2014-06-01

    The Big Bang nucleosynthesis (BBN) and the cosmic microwave background (CMB) anisotropies are the pillars of modern cosmology. It has recently been suggested that axion which is a dark matter candidate in the framework of the standard model could condensate in the early universe and induce photon cooling before the epoch of the photon last scattering. Although this may render a solution to the overproduction problem of primordial 7Li abundance, there arises another serious difficulty of overproducing D abundance. We propose a hybrid dark matter model with both axions and relic supersymmetric (SUSY) particles to solve both overproduction problems of the primordial D and 7Li abundances simultaneously. The BBN also serves to constrain the nature of neutrinos. Considering non-thermal photons produced in the decay of the heavy sterile neutrinos due to the magnetic moment, we explore the cosmological constraint on the strength of neutrino magnetic moment consistent with the observed light element abundances. Core-collapse supernovae eject huge flux of energetic neutrinos which affect explosive nucleosynthesis of rare isotopes like 7Li, 11B, 92Nb, 138La and 180Ta and r-process elements. Several isotopes depend strongly on the neutrino flavor oscillation due to the Mikheyev-Smirnov-Wolfenstein (MSW) effect. Combining the recent experimental constraints on θ13 with predicted and observed supernova-produced abundance ratio 11B/7Li encapsulated in the presolar grains from the Murchison meteorite, we show a marginal preference for an inverted neutrino mass hierarchy. We also discuss supernova relic neutrinos (SRN) that may indicate the softness of the equation of state (EoS) of nuclear matter and adiabatic conditions of the neutrino oscillation.

  1. Cosmological and supernova neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Kajino, T. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan Department of Astronomy, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033 (Japan); Aoki, W. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Balantekin, A. B. [Department of Physics, University of Wisconsin - Madison, Wisconsin 53706 (United States); Cheoun, M.-K. [Department of Physics, Soongsil University, Seoul 156-743 (Korea, Republic of); Hayakawa, T. [Japan Atomic Energy Agency, Shirakara-Shirane 2-4, Tokai-mura, Ibaraki 319-1195 (Japan); Hidaka, J. [National Astronomical Observatory, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Hirai, Y.; Shibagaki, S. [National Astronomical Observatory, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan and Department of Astronomy, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033 (Japan); Kusakabe, M. [School of Liberal Arts and Science, Korea Aerospace University, Goyang 412-791 (Korea, Republic of); Mathews, G. J. [Department of Physics, University of Notre Dame, IN 46556 (United States); Nakamura, K. [Waseda University, Ohkubo 3-4-1, Shinjuku, Tokyo 169-8555 (Japan); Pehlivan, Y. [Mimar Sinan GSÜ, Department of Physics, Şişli, İstanbul 34380 (Turkey); Suzuki, T. [Nihon University, Sakurajosui 3-25-40, Setagaya-ku, Tokyo 156-8550 (Japan)

    2014-06-24

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

  2. Effects of sterile neutrino and extra-dimension on big bang nucleosynthesis

    Science.gov (United States)

    Jang, Dukjae; Kusakabe, Motohiko; Cheoun, Myung-Ki

    2018-04-01

    We study effects of the sterile neutrino in the five-dimensional universe on the big bang nucleosynthesis (BBN). Since the five-dimensional universe model leads to an additional term in the Friedmann equation and the energy density of the sterile neutrino increases the total energy density, this model can affect the primordial abundance via changing the cosmic expansion rate. The energy density of the sterile neutrino can be determined by a rate equation for production of the sterile neutrino. We show that not only the mixing angle and the mass of the sterile neutrino, but also a resonant effect in the oscillation between sterile and active neutrinos is important to determine a relic abundance of the sterile neutrino. In this study, we also investigate how the sterile neutrino in extra-dimensional model can affect the BBN, and constrain the parameters related to the above properties of the sterile neutrino by using the observational primordial abundances of light elements.

  3. Supernova neutrinos and explosive nucleosynthesis

    Science.gov (United States)

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

    2014-05-01

    Core-collapse supernovae eject huge amount of flux of energetic neutrinos. We studied the explosive nucleosyn-thesis in supernovae and found that several isotopes 7Li, 11B, 92Nb, 138La and 180Ta as well as r-process nuclei are affected by the neutrino interactions. The abundance of these isotopes therefore depends strongly on the neutrino flavor oscillation due to the Mikheyev-Smirnov-Wolfenstein (MSW) effect. We discuss first how to determine the neutrino temperatures in order to explain the observed solar system abundances of these isotopes, combined with Galactic chemical evolution of the light nuclei and the heavy r-process elements. We then study the effects of neutrino oscillation on their abundances, and propose a novel method to determine the still unknown neutrino oscillation parameters, mass hierarchy and θ13, simultaneously. There is recent evidence that SiC X grains from the Murchison meteorite may contain supernova-produced light elements 11B and 7Li encapsulated in the presolar grains. Combining the recent experimental constraints on θ13, we show that our method sug-gests at a marginal preference for an inverted neutrino mass hierarchy. Finally, we discuss supernova relic neutrinos that may indicate the softness of the equation of state (EoS) of nuclear matter as well as adiabatic conditions of the neutrino oscillation.

  4. Supernova neutrinos and explosive nucleosynthesis

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-05-09

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

  5. Neutrinos

    CERN Multimedia

    CERN. Geneva

    2004-01-01

    The Standard Model predicts that the neutrinos are massless and do not mix. Generic extensions of the Standard Model predict that neutrinos are massive (but, very likely, much lighter than the charged fermions). Therefore, the search for neutrino masses and mixing tests the Standard Model and probes new phasics. Measurements of various features of the fluxes of atmospheric, solar and, more recently, reactor neutrinos have provided evidence for neutrino oscillations and therefore for neutrino masses and mixing. These results have significant theoretical implications: new physics exists, and its scale can be estimated. There are interesting lessons for grand unified theories and for models of extra dimensions. The measured neutrino flavor parameters pose a challenge to flavor models.

  6. Big bang nucleosynthesis and the cosmic neutrino background

    International Nuclear Information System (INIS)

    Cao Yun; Xing Zhizhong

    2013-01-01

    We present a brief overview of the neutrino decoupling and big bang nucleosynthesis in the early universe. The big bang relic neutrinos formed one of the backgrounds of the universe. A few possible ways to directly detect the cosmic neutrino background are briefly introduced, and particular attention is paid to the relic neutrino capture on b-decaying nuclei. (authors)

  7. Prospects for the direct detection of the cosmic neutrino background

    International Nuclear Information System (INIS)

    Ringwald, Andreas

    2009-01-01

    The existence of a cosmic neutrino background - the analogue of the cosmic microwave background - is a fundamental prediction of standard big bang cosmology. Up to now, the observational evidence for its existence is rather indirect and rests entirely on cosmological observations of, e.g., the light elemental abundances, the anisotropies in the cosmic microwave background, and the large scale distribution of matter. Here, we review more direct, weak interaction based detection techniques for the cosmic neutrino background in the present epoch and in our local neighbourhood. We show that, with current technology, all proposals are still off by some orders of magnitude in sensitivity to lead to a guaranteed detection of the relic neutrinos. The most promising laboratory search, based on neutrino capture on beta decaying nuclei, may be done in future experiments designed to measure the neutrino mass through decay kinematics.

  8. Prospects for the direct detection of the cosmic neutrino background

    International Nuclear Information System (INIS)

    Ringwald, Andreas

    2009-01-01

    The existence of a cosmic neutrino background - the analogue of the cosmic microwave background - is a fundamental prediction of standard big bang cosmology. Up to now, the observational evidence for its existence is rather indirect and rests entirely on cosmological observations of, e.g., the light elemental abundances, the anisotropies in the cosmic microwave background, and the large scale distribution of matter. Here, we review more direct, weak interaction based detection techniques for the cosmic neutrino background in the present epoch and in our local neighbourhood. We show that, with current technology, all proposals are still off by some orders of magnitude in sensitivity to lead to a guaranteed detection of the relic neutrinos. The most promising laboratory search, based on neutrino capture on beta decaying nuclei, may be done in future experiments designed to measure the neutrino mass through decay kinematics. (orig.)

  9. Probing neutrino dark energy with extremely high-energy cosmic neutrinos

    International Nuclear Information System (INIS)

    Ringwald, A.; Schrempp, L.

    2006-06-01

    Recently, a new non-Standard Model neutrino interaction mediated by a light scalar field was proposed, which renders the big-bang relic neutrinos of the cosmic neutrino background a natural dark energy candidate, the so-called Neutrino Dark Energy. As a further consequence of this interaction, the neutrino masses become functions of the neutrino energy densities and are thus promoted to dynamical, time/redshift dependent quantities. Such a possible neutrino mass variation introduces a redshift dependence into the resonance energies associated with the annihilation of extremely high-energy cosmic neutrinos on relic anti-neutrinos and vice versa into Z-bosons. In general, this annihilation process is expected to lead to sizeable absorption dips in the spectra to be observed on earth by neutrino observatories operating in the relevant energy region above 10 13 GeV. In our analysis, we contrast the characteristic absorption features produced by constant and varying neutrino masses, including all thermal background effects caused by the relic neutrino motion. We firstly consider neutrinos from astrophysical sources and secondly neutrinos originating from the decomposition of topological defects using the appropriate fragmentation functions. On the one hand, independent of the nature of neutrino masses, our results illustrate the discovery potential for the cosmic neutrino background by means of relic neutrino absorption spectroscopy. On the other hand, they allow to estimate the prospects for testing its possible interpretation as source of Neutrino Dark Energy within the next decade by the neutrino observatories ANITA and LOFAR. (Orig.)

  10. (N)LSP decays and gravitino dark matter relic abundance in big divisor (nearly) SLagy D3/D7μ-split SUSY

    Science.gov (United States)

    Dhuria, Mansi; Misra, Aalok

    2013-02-01

    Using the (nearly) Ricci-flat Swiss-Cheese metric of Misra (2012) [1], in the context of a mobile space-time filling D3-brane restricted to a nearly special Lagrangian sub-manifold (in the large volume limit, the pull-back of the Kähler form close to zero and the real part of the pull-back of e, θ=π/2 times the nowhere-vanishing holomorphic three-form providing the volume form on the three-cycle) of the "big" divisor with (fluxed stacks of) space-time filling D7-branes also wrapping the "big" divisor (corresponding to a local minimum), we provide an explicit identification of the electron and the u-quark, as well as their SU (2-singlet cousins, with fermionic superpartners of four Wilson line moduli; their superpartners turn out to be very heavy, the Higgsino-mass parameter turns out to be large, one obtains one light (with a mass of 125 GeV) and one heavy Higgs and the gluino is long lived (from a collider point of view) providing a possible realization of "μ-Split Supersymmetry". By explicitly calculating the lifetimes of decays of the co-NLSPs - the first generation squark/slepton and a neutralino - to the LSP - the gravitino - as well as gravitino decays, we verify that BBN constraints relevant to the former as well as the requirement of the latter to be (more than) the age of the universe, are satisfied. For the purpose of calculation of the gravitino relic density in terms of the neutralino/slepton relic density, we evaluate the latter by evaluating the neutralino/slepton (co-)annihilation cross sections and hence show that the former satisfies the requirement for a dark matter candidate.

  11. (N)LSP decays and gravitino dark matter relic abundance in big divisor (nearly) SLagy D3/D7μ-split SUSY

    International Nuclear Information System (INIS)

    Dhuria, Mansi; Misra, Aalok

    2013-01-01

    Using the (nearly) Ricci-flat Swiss-Cheese metric of Misra (2012) [1], in the context of a mobile space–time filling D3-brane restricted to a nearly special Lagrangian sub-manifold (in the large volume limit, the pull-back of the Kähler form close to zero and the real part of the pull-back of e −iθ , θ=(π)/2 times the nowhere-vanishing holomorphic three-form providing the volume form on the three-cycle) of the “big” divisor with (fluxed stacks of) space–time filling D7-branes also wrapping the “big” divisor (corresponding to a local minimum), we provide an explicit identification of the electron and the u-quark, as well as their SU(2) L -singlet cousins, with fermionic superpartners of four Wilson line moduli; their superpartners turn out to be very heavy, the Higgsino-mass parameter turns out to be large, one obtains one light (with a mass of 125 GeV) and one heavy Higgs and the gluino is long lived (from a collider point of view) providing a possible realization of “μ-Split Supersymmetry”. By explicitly calculating the lifetimes of decays of the co-NLSPs – the first generation squark/slepton and a neutralino – to the LSP – the gravitino – as well as gravitino decays, we verify that BBN constraints relevant to the former as well as the requirement of the latter to be (more than) the age of the universe, are satisfied. For the purpose of calculation of the gravitino relic density in terms of the neutralino/slepton relic density, we evaluate the latter by evaluating the neutralino/slepton (co-)annihilation cross sections and hence show that the former satisfies the requirement for a dark matter candidate.

  12. (N)LSP decays and gravitino dark matter relic abundance in big divisor (nearly) SLagy D3/D7{mu}-split SUSY

    Energy Technology Data Exchange (ETDEWEB)

    Dhuria, Mansi, E-mail: mansidph@iitr.ernet.in [Department of Physics, Indian Institute of Technology, Roorkee 247 667, Uttaranchal (India); Misra, Aalok, E-mail: aalokfph@iitr.ernet.in [Department of Physics, Indian Institute of Technology, Roorkee 247 667, Uttaranchal (India)

    2013-02-21

    Using the (nearly) Ricci-flat Swiss-Cheese metric of Misra (2012) [1], in the context of a mobile space-time filling D3-brane restricted to a nearly special Lagrangian sub-manifold (in the large volume limit, the pull-back of the Kaehler form close to zero and the real part of the pull-back of e{sup -i{theta}}, {theta}=({pi})/2 times the nowhere-vanishing holomorphic three-form providing the volume form on the three-cycle) of the 'big' divisor with (fluxed stacks of) space-time filling D7-branes also wrapping the 'big' divisor (corresponding to a local minimum), we provide an explicit identification of the electron and the u-quark, as well as their SU(2){sub L}-singlet cousins, with fermionic superpartners of four Wilson line moduli; their superpartners turn out to be very heavy, the Higgsino-mass parameter turns out to be large, one obtains one light (with a mass of 125 GeV) and one heavy Higgs and the gluino is long lived (from a collider point of view) providing a possible realization of '{mu}-Split Supersymmetry'. By explicitly calculating the lifetimes of decays of the co-NLSPs - the first generation squark/slepton and a neutralino - to the LSP - the gravitino - as well as gravitino decays, we verify that BBN constraints relevant to the former as well as the requirement of the latter to be (more than) the age of the universe, are satisfied. For the purpose of calculation of the gravitino relic density in terms of the neutralino/slepton relic density, we evaluate the latter by evaluating the neutralino/slepton (co-)annihilation cross sections and hence show that the former satisfies the requirement for a dark matter candidate.

  13. How to detect the cosmic neutrino background?

    International Nuclear Information System (INIS)

    Ringwald, A.

    2003-01-01

    A measurement of the big bang relic neutrinos would open a new window to the early universe. We review various possibilities to detect this cosmic neutrino background and substantiate the assertion that - apart from the rather indirect evidence to be gained from cosmology and large-scale structure formation - the annihilation of ultrahigh energy cosmic neutrinos with relic anti-neutrinos (or vice versa) on the Z-resonance is a unique process having sensitivity to the relic neutrinos, if a sufficient flux at E ν i res =M Z 2 /(2m ν i )=4.10 22 eV (0.1 eV/m ν i ) exists. The associated absorption dips in the ultrahigh energy cosmic neutrino spectrum may be searched for at forthcoming neutrino and air shower detectors. The associated protons and photons may have been seen already in form of the cosmic ray events above the Greisen-Zatsepin-Kuzmin cutoff. (orig.)

  14. Dark-matter sterile neutrinos in models with a gauge singlet in the Higgs sector

    International Nuclear Information System (INIS)

    Petraki, Kalliopi; Kusenko, Alexander

    2008-01-01

    Sterile neutrino with mass of several keV can be the cosmological dark matter, can explain the observed velocities of pulsars, and can play an important role in the formation of the first stars. We describe the production of sterile neutrinos in a model with an extended Higgs sector, in which the Majorana mass term is generated by the vacuum expectation value of a gauge-singlet Higgs boson. In this model the relic abundance of sterile neutrinos does not necessarily depend on their mixing angles, the free-streaming length can be much smaller than in the case of warm dark matter produced by neutrino oscillations, and, therefore, some of the previously quoted bounds do not apply. The presence of the gauge singlet in the Higgs sector has important implications for the electroweak phase transition, baryogenesis, and the upcoming experiments at the Large Hadron Collider and a Linear Collider.

  15. Common origin of neutrino mass, dark matter and Dirac leptogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Borah, Debasish [Department of Physics, Indian Institute of Technology Guwahati, Assam 781039 (India); Dasgupta, Arnab, E-mail: dborah@iitg.ernet.in, E-mail: arnab.d@iopb.res.in [Institute of Physics, HBNI, Sachivalaya Marg, Bhubaneshwar 751005 (India)

    2016-12-01

    We study the possibility of generating tiny Dirac neutrino masses at one loop level through the scotogenic mechanism such that one of the particles going inside the loop can be a stable cold dark matter (DM) candidate. Majorana mass terms of singlet fermions as well as tree level Dirac neutrino masses are prevented by incorporating the presence of additional discrete symmetries in a minimal fashion, which also guarantee the stability of the dark matter candidate. Due to the absence of total lepton number violation, the observed baryon asymmetry of the Universe is generated through the mechanism of Dirac leptogenesis where an equal and opposite amount of leptonic asymmetry is generated in the left and right handed sectors which are prevented from equilibration due to tiny Dirac Yukawa couplings. Dark matter relic abundance is generated through its usual freeze-out at a temperature much below the scale of leptogenesis. We constrain the relevant parameter space from neutrino mass, baryon asymmetry, Planck bound on dark matter relic abundance, and latest LUX bound on spin independent DM-nucleon scattering cross section. We also discuss the charged lepton flavour violation (μ → e γ) and electric dipole moment of electron in this model in the light of the latest experimental data and constrain the parameter space of the model.

  16. Neutrino mass from Cosmology

    CERN Document Server

    Lesgourgues, Julien

    2012-01-01

    Neutrinos can play an important role in the evolution of the Universe, modifying some of the cosmological observables. In this contribution we summarize the main aspects of cosmological relic neutrinos and we describe how the precision of present cosmological data can be used to learn about neutrino properties, in particular their mass, providing complementary information to beta decay and neutrinoless double-beta decay experiments. We show how the analysis of current cosmological observations, such as the anisotropies of the cosmic microwave background or the distribution of large-scale structure, provides an upper bound on the sum of neutrino masses of order 1 eV or less, with very good perspectives from future cosmological measurements which are expected to be sensitive to neutrino masses well into the sub-eV range.

  17. Particle Astrophysics of Neutrinos

    Indian Academy of Sciences (India)

    Amol Dighe

    Energy spectra of neutrino sources. ASPERA. Page 4. Some unique features of neutrinos. The second most abundant particles in the universe. Cosmic microwave background photons: 400 / cm3. Cosmic background neutrinos: 330 / cm3. The lightest massive particles. A million times lighter than the electron. No direct mass ...

  18. Neutrinos in an expanding Universe

    International Nuclear Information System (INIS)

    Wigmans, Richard

    2015-01-01

    The Universe contains several billion neutrinos for each nucleon. In this paper, we follow the history of these relic neutrinos as the Universe expanded. At present, their typical velocity is a few hundred km/s and, therefore, their spectra are affected by gravitational forces. This may have led to a phenomenon that could explain two of todays great mysteries: The large-scale structure of the Universe and the increasing rate at which it expands. (paper)

  19. Effects of sterile neutrinos and an extra dimension on big bang nucleosynthesis

    Science.gov (United States)

    Jang, Dukjae; Kusakabe, Motohiko; Cheoun, Myung-Ki

    2018-02-01

    By assuming the existence of extra-dimensional sterile neutrinos in the big bang nucleosynthesis (BBN) epoch, we investigate the sterile neutrino (νs) effects on the BBN and constrain some parameters associated with the νs properties. First, for the cosmic expansion rate, we take into account effects of a five-dimensional bulk and intrinsic tension of the brane embedded in the bulk and constrain a key parameter of the extra dimension by using the observational element abundances. Second, effects of the νs traveling on or off the brane are considered. In this model, the effective mixing angle between a νs and an active neutrino depends on energy, which may give rise to a resonance effect on the mixing angle. Consequently, the reaction rate of the νs can be drastically changed during the cosmic evolution. We estimated abundances and temperature of the νs by solving the rate equation as a function of temperature until the sterile neutrino decoupling. We then find that the relic abundance of the νs is drastically enhanced by the extra dimension and maximized for a characteristic resonance energy Eres≳0.01 GeV . Finally, some constraints related to the νs, i.e., mixing angle and mass difference, are discussed in detail with the comparison of our BBN calculations corrected by the extra-dimensional νs to observational data on light element abundances.

  20. Neutrino mass, leptogenesis and FIMP dark matter in a U(1){sub B-L} model

    Energy Technology Data Exchange (ETDEWEB)

    Biswas, Anirban; Khan, Sarif [Harish-Chandra Research Institute, Allahabad (India); Homi Bhabha National Institute, Training School Complex, Mumbai (India); Choubey, Sandhya [Harish-Chandra Research Institute, Allahabad (India); Homi Bhabha National Institute, Training School Complex, Mumbai (India); AlbaNova University Center, Department of Theoretical Physics, School of Engineering Sciences, KTH Royal Institute of Technology, Stockholm (Sweden)

    2017-12-15

    The Standard Model (SM) is inadequate to explain the origin of tiny neutrino masses, the dark matter (DM) relic abundance and the baryon asymmetry of the Universe. In this work, to address all three puzzles, we extend the SM by a local U(1){sub B-L} gauge symmetry, three right-handed (RH) neutrinos for the cancellation of gauge anomalies and two complex scalars having non-zero U(1){sub B-L} charges. All the newly added particles become massive after the breaking of the U(1){sub B-L} symmetry by the vacuum expectation value (VEV) of one of the scalar fields φ{sub H}. The other scalar field, φ{sub DM}, which does not have any VEV, becomes automatically stable and can be a viable DM candidate. Neutrino masses are generated using the Type-I seesaw mechanism, while the required lepton asymmetry to reproduce the observed baryon asymmetry can be attained from the CP violating out of equilibrium decays of the RH neutrinos in TeV scale. More importantly within this framework, we study in detail the production of DM via the freeze-in mechanism considering all possible annihilation and decay processes. Finally, we find a situation when DM is dominantly produced from the annihilation of the RH neutrinos, which are at the same time also responsible for neutrino mass generation and leptogenesis. (orig.)

  1. Neutrino mass, leptogenesis and FIMP dark matter in a U(1)_{B-L} model

    Science.gov (United States)

    Biswas, Anirban; Choubey, Sandhya; Khan, Sarif

    2017-12-01

    The Standard Model (SM) is inadequate to explain the origin of tiny neutrino masses, the dark matter (DM) relic abundance and the baryon asymmetry of the Universe. In this work, to address all three puzzles, we extend the SM by a local U(1)_{B-L} gauge symmetry, three right-handed (RH) neutrinos for the cancellation of gauge anomalies and two complex scalars having non-zero U(1)_{B-L} charges. All the newly added particles become massive after the breaking of the U(1)_{B-L} symmetry by the vacuum expectation value (VEV) of one of the scalar fields φ _H. The other scalar field, φ _DM, which does not have any VEV, becomes automatically stable and can be a viable DM candidate. Neutrino masses are generated using the Type-I seesaw mechanism, while the required lepton asymmetry to reproduce the observed baryon asymmetry can be attained from the CP violating out of equilibrium decays of the RH neutrinos in TeV scale. More importantly within this framework, we study in detail the production of DM via the freeze-in mechanism considering all possible annihilation and decay processes. Finally, we find a situation when DM is dominantly produced from the annihilation of the RH neutrinos, which are at the same time also responsible for neutrino mass generation and leptogenesis.

  2. Relic gravitational waves and cosmology

    International Nuclear Information System (INIS)

    Grishchuk, Leonid P

    2005-01-01

    The paper begins with a brief recollection of interactions of the author with Ya B Zeldovich in the context of the study of relic gravitational waves. The principles and early results on the quantum-mechanical generation of cosmological perturbations are then summarized. The expected amplitudes of relic gravitational waves differ in various frequency windows, and therefore the techniques and prospects of their detection are distinct. One section of the paper describes the present state of efforts in direct detection of relic gravitational waves. Another section is devoted to indirect detection via the anisotropy and polarization measurements of the cosmic microwave background (CMB) radiation. It is emphasized throughout the paper that the inference about the existence and expected amount of relic gravitational waves is based on a solid theoretical foundation and the best available cosmological observations. It is also explained in great detail what went wrong with the so-called 'inflationary gravitational waves', whose amount is predicted by inflationary theorists to be negligibly small, thus depriving them of any observational significance. (reviews of topical problems)

  3. Anti-neutrino imprint in solar neutrino flare

    Science.gov (United States)

    Fargion, D.

    2006-10-01

    A future neutrino detector at megaton mass might enlarge the neutrino telescope thresholds revealing cosmic supernova background and largest solar flares (SFs) neutrinos. Indeed the solar energetic (Ep>100 MeV) flare particles (protons, α), while scattering among themselves on solar corona atmosphere must produce prompt charged pions, whose chain decays are source of a solar (electron muon) neutrino 'flare' (at tens or hundreds MeV energy). These brief (minutes) neutrino 'bursts' at largest flare peak may overcome by three to five orders of magnitude the steady atmospheric neutrino noise on the Earth, possibly leading to their detection above detection thresholds (in a full mixed three flavour state). Moreover the birth of anti-neutrinos at a few tens of MeV very clearly flares above a null thermal 'hep' anti-neutrino solar background and also above a tiny supernova relic and atmospheric noise. The largest prompt solar anti-neutrino 'burst' may be well detected in future Super Kamikande (gadolinium implemented) anti-neutrino \\bar\

  4. Neutrinos and large-scale structure

    International Nuclear Information System (INIS)

    Eisenstein, Daniel J.

    2015-01-01

    I review the use of cosmological large-scale structure to measure properties of neutrinos and other relic populations of light relativistic particles. With experiments to measure the anisotropies of the cosmic microwave anisotropies and the clustering of matter at low redshift, we now have securely measured a relativistic background with density appropriate to the cosmic neutrino background. Our limits on the mass of the neutrino continue to shrink. Experiments coming in the next decade will greatly improve the available precision on searches for the energy density of novel relativistic backgrounds and the mass of neutrinos

  5. Neutrinos and large-scale structure

    Energy Technology Data Exchange (ETDEWEB)

    Eisenstein, Daniel J. [Daniel J. Eisenstein, Harvard-Smithsonian Center for Astrophysics, 60 Garden St., MS #20, Cambridge, MA 02138 (United States)

    2015-07-15

    I review the use of cosmological large-scale structure to measure properties of neutrinos and other relic populations of light relativistic particles. With experiments to measure the anisotropies of the cosmic microwave anisotropies and the clustering of matter at low redshift, we now have securely measured a relativistic background with density appropriate to the cosmic neutrino background. Our limits on the mass of the neutrino continue to shrink. Experiments coming in the next decade will greatly improve the available precision on searches for the energy density of novel relativistic backgrounds and the mass of neutrinos.

  6. Two-loop neutrino model with exotic leptons

    Science.gov (United States)

    Okada, Hiroshi; Orikasa, Yuta

    2016-01-01

    We propose a two-loop induced neutrino mass model, in which we show some bench mark points to satisfy the observed neutrino oscillation, the constraints of lepton flavor violations, and the relic density in the coannihilation system satisfying the current upper bound on the spin independent scattering cross section with nuclei. We also discuss new sources of muon anomalous magnetic moments.

  7. Neutrino Physics

    CERN Multimedia

    CERN. Geneva; Dydak, Friedrich

    2001-01-01

    Starting from a review of theoretical concepts and experimental results in the early years of neutrino physics after Pauli's 1930 letter, today's double role of the neutrino as a cornerstone of the Standard Model and as a promising probe of physics beyond the Standard Model will be discussed. Topics comprise: - Conventional neutrino beams - Neutrinos as probes of the nucleon structure - Neutrinos from the universe - Dirac or Majorana neutrinos - Neutrino oscillations - MNS matrix - CP violation in the lepton sector - Neutrino factory.

  8. Neutrino Physics

    CERN Multimedia

    CERN. Geneva. Audiovisual Unit

    2002-01-01

    Starting from a review of theoretical concepts and experimental results in the early years of neutrino physics after Pauli's 1930 letter, today's double role of the neutrino as a cornerstone of the Standard Model and as a promising probe of physics beyond the Standard Model will be discussed. Topics comprise: - Conventional neutrino beams - Neutrinos as probes of the nucleon structure - Neutrinos from the universe - Dirac or Majorana neutrinos - Neutrino oscillations - MNS matrix - CP violation in the lepton sector - Neutrino factory.

  9. Relic gravitons and viscous cosmologies

    International Nuclear Information System (INIS)

    Cataldo, Mauricio; Mella, Patricio

    2006-01-01

    Previously it was shown that there exists a class of viscous cosmological models which violate the dominant energy condition for a limited amount of time after which they are smoothly connected to the ordinary radiation era (which preserves the dominant energy conditions). This violation of the dominant energy condition at an early cosmological epoch may influence the slopes of energy spectra of relic gravitons that might be of experimental relevance. However, the bulk viscosity coefficient of these cosmologies became negative during the ordinary radiation era, and then the entropy of the sources driving the geometry decreases with time. We show that in the presence of viscous sources with a linear barotropic equation of state p=γρ we get viscous cosmological models with positive bulk viscous stress during all their evolution, and hence the matter entropy increases with the expansion time. In other words, in the framework of viscous cosmologies, there exist isotropic models compatible with the standard second law of thermodynamics which also may influence the slopes of energy spectra of relic gravitons

  10. Insights into neutrino decoupling gleaned from considerations of the role of electron mass

    Science.gov (United States)

    Grohs, E.; Fuller, George M.

    2017-10-01

    We present calculations showing how electron rest mass influences entropy flow, neutrino decoupling, and Big Bang Nucleosynthesis (BBN) in the early universe. To elucidate this physics and especially the sensitivity of BBN and related epochs to electron mass, we consider a parameter space of rest mass values larger and smaller than the accepted vacuum value. Electromagnetic equilibrium, coupled with the high entropy of the early universe, guarantees that significant numbers of electron-positron pairs are present, and dominate over the number of ionization electrons to temperatures much lower than the vacuum electron rest mass. Scattering between the electrons-positrons and the neutrinos largely controls the flow of entropy from the plasma into the neutrino seas. Moreover, the number density of electron-positron-pair targets can be exponentially sensitive to the effective in-medium electron mass. This entropy flow influences the phasing of scale factor and temperature, the charged current weak-interaction-determined neutron-to-proton ratio, and the spectral distortions in the relic neutrino energy spectra. Our calculations show the sensitivity of the physics of this epoch to three separate effects: finite electron mass, finite-temperature quantum electrodynamic (QED) effects on the plasma equation of state, and Boltzmann neutrino energy transport. The ratio of neutrino to plasma-component energy scales manifests in Cosmic Microwave Background (CMB) observables, namely the baryon density and the radiation energy density, along with the primordial helium and deuterium abundances. Our results demonstrate how the treatment of in-medium electron mass (i.e., QED effects) could translate into an important source of uncertainty in extracting neutrino and beyond-standard-model physics limits from future high-precision CMB data.

  11. Insights into neutrino decoupling gleaned from considerations of the role of electron mass

    Directory of Open Access Journals (Sweden)

    E. Grohs

    2017-10-01

    Full Text Available We present calculations showing how electron rest mass influences entropy flow, neutrino decoupling, and Big Bang Nucleosynthesis (BBN in the early universe. To elucidate this physics and especially the sensitivity of BBN and related epochs to electron mass, we consider a parameter space of rest mass values larger and smaller than the accepted vacuum value. Electromagnetic equilibrium, coupled with the high entropy of the early universe, guarantees that significant numbers of electron–positron pairs are present, and dominate over the number of ionization electrons to temperatures much lower than the vacuum electron rest mass. Scattering between the electrons–positrons and the neutrinos largely controls the flow of entropy from the plasma into the neutrino seas. Moreover, the number density of electron–positron-pair targets can be exponentially sensitive to the effective in-medium electron mass. This entropy flow influences the phasing of scale factor and temperature, the charged current weak-interaction-determined neutron-to-proton ratio, and the spectral distortions in the relic neutrino energy spectra. Our calculations show the sensitivity of the physics of this epoch to three separate effects: finite electron mass, finite-temperature quantum electrodynamic (QED effects on the plasma equation of state, and Boltzmann neutrino energy transport. The ratio of neutrino to plasma–component energy scales manifests in Cosmic Microwave Background (CMB observables, namely the baryon density and the radiation energy density, along with the primordial helium and deuterium abundances. Our results demonstrate how the treatment of in-medium electron mass (i.e., QED effects could translate into an important source of uncertainty in extracting neutrino and beyond-standard-model physics limits from future high-precision CMB data.

  12. Perspectives for Detection of a Higgsino-like Relic Neutralino

    CERN Document Server

    Bottino, A; Mignola, G; Olechowski, M; Scopel, S

    1996-01-01

    It has been conjectured by Ambrosanio, Kane, Kribs, Martin and Mrenna (AKM) that the CDF event $p \\bar p \\to e^+ e^- \\gamma \\gamma + missing E_T$ is due to a decay chain involving two neutralino states (the lightest and the next-to-lightest ones). The lightest neutralino ($\\chi_{AKM}$) has been further considered by Kane and Wells as a candidate for cold dark matter. In this paper we examine the properties of relic $\\chi_{AKM}$'s in their full parameter space, and examine the perspectives for detection by comparing theoretical predictions to sensitivities of various experimental searches. We find that for most regions of the parameter space the detectability of a relic $\\chi_{AKM}$ would require quite substantial improvements in current experimental sensitivities. The measurements of neutrino fluxes from the center of the Earth and of an excess of $\\bar{p}/p$ in cosmic rays are shown to offer some favorable perspectives for investigating a region of the the model.

  13. Multi-component fermionic dark matter and IceCube PeV scale neutrinos in left-right model with gauge unification

    Science.gov (United States)

    Borah, Debasish; Dasgupta, Arnab; Dey, Ujjal Kumar; Patra, Sudhanwa; Tomar, Gaurav

    2017-09-01

    We consider a simple extension of the minimal left-right symmetric model (LRSM) in order to explain the PeV neutrino events seen at the IceCube experiment from a heavy decaying dark matter. The dark matter sector is composed of two fermions: one at PeV scale and the other at TeV scale such that the heavier one can decay into the lighter one and two neutrinos. The gauge annihilation cross sections of PeV dark matter are not large enough to generate its relic abundance within the observed limit. We include a pair of real scalar triplets Ω L,R which can bring the thermally overproduced PeV dark matter abundance into the observed range through late time decay and consequent entropy release thereby providing a consistent way to obtain the correct relic abundance without violating the unitarity bound on dark matter mass. Another scalar field, a bitriplet under left-right gauge group is added to assist the heavier dark matter decay. The presence of an approximate global U(1) X symmetry can naturally explain the origin of tiny couplings required for long-lived nature of these decaying particles. We also show, how such an extended LRSM can be incorporated within a non-supersymmetric SO(10) model where the gauge coupling unification at a very high scale naturally accommodate a PeV scale intermediate symmetry, required to explain the PeV events at IceCube.

  14. Making the most of the relic density for dark matter searches at the LHC 14 TeV Run

    International Nuclear Information System (INIS)

    Busoni, Giorgio; Simone, Andrea De; Jacques, Thomas; Morgante, Enrico; Riotto, Antonio

    2015-01-01

    As the LHC continues to search for new weakly interacting particles, it is important to remember that the search is strongly motivated by the existence of dark matter. In view of a possible positive signal, it is essential to ask whether the newly discovered weakly interacting particle can be be assigned the label 'dark matter'. Within a given set of simplified models and modest working assumptions, we reinterpret the relic abundance bound as a relic abundance range, and compare the parameter space yielding the correct relic abundance with projections of the Run II exclusion regions. Assuming that dark matter is within the reach of the LHC, we also make the comparison with the potential 5σ discovery regions. Reversing the logic, relic density calculations can be used to optimize dark matter searches by motivating choices of parameters where the LHC can probe most deeply into the dark matter parameter space. In the event that DM is seen outside of the region giving the correct relic abundance, we will learn that either thermal relic DM is ruled out in that model, or the DM-quark coupling is suppressed relative to the DM coupling strength to other SM particles

  15. Cosmic relics from the big bang

    International Nuclear Information System (INIS)

    Hall, L.J.

    1988-12-01

    A brief introduction to the big bang picture of the early universe is given. Dark matter is discussed; particularly its implications for elementary particle physics. A classification scheme for dark matter relics is given. 21 refs., 11 figs., 1 tab

  16. Cosmic relics from the big bang

    Energy Technology Data Exchange (ETDEWEB)

    Hall, L.J.

    1988-12-01

    A brief introduction to the big bang picture of the early universe is given. Dark matter is discussed; particularly its implications for elementary particle physics. A classification scheme for dark matter relics is given. 21 refs., 11 figs., 1 tab.

  17. Indirect search for neutralino dark matter with high energy neutrinos

    International Nuclear Information System (INIS)

    Barger, V.; Halzen, Francis; Hooper, Dan; Kao, Chung

    2002-01-01

    We investigate the prospects of indirect searches for supersymmetric neutralino dark matter. Relic neutralinos gravitationally accumulate in the Sun and their annihilations produce high energy neutrinos. Muon neutrinos of this origin can be seen in large detectors such as AMANDA, IceCube, and ANTARES. We evaluate the relic density and the detection rate in several models--the minimal supersymmetric model, minimal supergravity, and supergravity with nonuniversal Higgs boson masses at the grand unification scale. We make realistic estimates for the indirect detection rates including effects of the muon detection threshold, quark hadronization, and solar absorption. We find good prospects for detection of neutralinos with mass above 200 GeV

  18. Neutrino physics

    International Nuclear Information System (INIS)

    Gil-Botella, I.

    2011-01-01

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

  19. Neutrino mass in flavor dependent gauged lepton model

    Science.gov (United States)

    Nomura, Takaaki; Okada, Hiroshi

    2018-03-01

    We study a neutrino model introducing an additional nontrivial gauged lepton symmetry where the neutrino masses are induced at two-loop level, while the first and second charged-leptons of the standard model are done at one-loop level. As a result of the model structure, we can predict one massless active neutrino, and there is a dark matter candidate. Then we discuss the neutrino mass matrix, muon anomalous magnetic moment, lepton flavor violations, oblique parameters, and relic density of dark matter, taking into account the experimental constraints.

  20. Neutrino cosmology

    International Nuclear Information System (INIS)

    Berstein, J.

    1984-01-01

    These lectures offer a self-contained review of the role of neutrinos in cosmology. The first part deals with the question 'What is a neutrino.' and describes in a historical context the theoretical ideas and experimental discoveries related to the different types of neutrinos and their properties. The basic differences between the Dirac neutrino and the Majorana neutrino are pointed out and the evidence for different neutrino 'flavours', neutrino mass, and neutrino oscillations is discussed. The second part summarizes current views on cosmology, particularly as they are affected by recent theoretical and experimental advances in high-energy particle physics. Finally, the close relationship between neutrino physics and cosmology is brought out in more detail, to show how cosmological constraints can limit the various theoretical possibilities for neutrinos and, more particularly, how increasing knowledge of neutrino properties can contribute to our understanding of the origin, history, and future of the Universe. The level is that of the beginning graduate student. (orig.)

  1. RELICS of the Cosmic Dawn

    Science.gov (United States)

    Bradac, Marusa; Coe, Dan; Strait, Victoria; Salmon, Brett; Hoag, Austin; Bradley, Larry; Ryan, Russell; Dawson, Will; Zitrin, Adi; Jones, Christine; Sharon, Keren; Trenti, Michele; Stark, Daniel; Oesch, Pascal; Lam, Danel; Carrasco Nunez, Daniela Patricia; Paterno-Mahler, Rachel; Frye, Brenda

    2018-05-01

    When did galaxies start forming stars? What is the role of distant galaxies in galaxy formation models and epoch of reionization? Recent observations indicate at least two critical puzzles in these studies. (1) First galaxies might have started forming stars earlier than previously thought (knowledge of stellar masses, ages, and star formation rates at this epoch requires measuring both rest-frame UV and optical light, which only Spitzer and HST can probe at z 6-11 for a large enough sample of typical galaxies. To address this cosmic puzzle, we propose to complete deep Spitzer imaging of the fields behind the 10 most powerful cosmic telescopes selected using HST, Spitzer, and Planck data from the RELICS and SRELICS programs (Reionization Lensing Cluster Survey; 41 clusters, 190 HST orbits, 440 Spitzer hours). 6 clusters out of 10 are still lacking deep data. This proposal will be a valuable Legacy complement to the existing IRAC deep surveys, and it will open up a new parameter space by probing the ordinary yet magnified population with much improved sample variance. The program will allow us to study stellar properties of a large number, 60 galaxies at z 6-11. Deep Spitzer data will be crucial to unambiguously measure their stellar properties (age, SFR, M*). Finally this proposal will establish the presence (or absence) of an unusually early established stellar population, as was recently observed in MACS1149JD at z 9. If confirmed in a larger sample, this result will require a paradigm shift in our understanding of the earliest star formation.

  2. RELICS of the Cosmic Dawn

    Science.gov (United States)

    Bradac, Marusa; Coe, Dan; Huang, Kuang-Han; Salmon, Brett; Hoag, Austin; Bradley, Larry; Ryan, Russell; Dawson, Will; Zitrin, Adi; Jones, Christine; Sharon, Keren; Trentu, Michele; Stark, Daniel; Bouwens, Rychard; Oesch, Pascal; Lam, Daniel; Patricia Carasco Nunez, Daniela; Paterno-Mahler, Rachel; Strait, Victoria

    2017-10-01

    When did galaxies start forming stars? What is the role of distant galaxies in galaxy formation models and epoch of reionization? Recent observations indicate at least two critical puzzles in these studies. (1) First galaxies might have started forming stars earlier than previously thought (Big Bang). (2) It is still unclear what is their star formation history and whether these galaxies can reionize the Universe. Accurate knowledge of stellar masses, ages, and star formation rates at this epoch requires measuring both rest-frame UV and optical light, which only Spitzer and HST can probe at z 6-11 for a large enough sample of typical galaxies. To address this cosmic puzzle, we propose Spitzer imaging of the fields behind the most powerful cosmic telescopes selected using HST, Spitzer, and Planck data from the RELICS and SRELICS programs (Reionization Lensing Cluster Survey; 41 clusters, 190 HST orbits, 550 Spitzer hours). This proposal will be a valuable Legacy complement to the existing IRAC deep surveys, and it will open up a new parameter space by probing the ordinary yet magnified population with much improved sample variance. The program will allow us to study stellar properties of a large number, 20 galaxies at z 6-11. Deep Spitzer data will be crucial to unambiguously measure their stellar properties (age, SFR, M*). Finally this proposal is a unique opportunity to establish the presence (or absence) of an unusually early established stellar population, as was recently observed in MACS1149JD at z 9. If confirmed, this result will require a paradigm shift in our understanding of the earliest star formation.

  3. Cosmic selection rule for the glueball dark matter relic density

    Science.gov (United States)

    Soni, Amarjit; Xiao, Huangyu; Zhang, Yue

    2017-10-01

    We point out a unique mechanism to produce the relic abundance for the glueball dark matter from a gauged SU (N )d hidden sector which is bridged to the standard model sector through heavy vectorlike quarks colored under gauge interactions from both sides. A necessary ingredient of our assumption is that the vectorlike quarks, produced either thermally or nonthermally, are abundant enough to dominate the universe for some time in the early universe. They later undergo dark color confinement and form unstable vectorlike-quarkonium states which annihilate decay and reheat the visible and dark sectors. The ratio of entropy dumped into two sectors and the final energy budget in the dark glueballs is only determined by low energy parameters, including the intrinsic scale of the dark SU (N )d , Λd, and number of dark colors, Nd, but depend weakly on parameters in the ultraviolet such as the vectorlike quark mass or the initial condition. We call this a cosmic selection rule for the glueball dark matter relic density.

  4. Neutrino mass?

    International Nuclear Information System (INIS)

    Kayser, B.

    1992-01-01

    After arguing that we should be looking for evidence of neutrino mass, we illustrate the possible consequences of neutrino mass and mixing. We then turn to the question of whether neutrinos are their own antiparticles, and to the process which may answer this question: neutrinoless double beta decay. Next, we review the proposed Mikheyev-Smirnov-Wolfenstein solution to the solar neutrino problem, and discuss models which can generate neutrino electromagnetic moments large enough to play a role in the sun. Finally, we consider how the possible 17 keV neutrino, if real, would fit in with everything we know about neutrinos. (orig.)

  5. Observing a light dark matter beam with neutrino experiments

    Science.gov (United States)

    Deniverville, Patrick; Pospelov, Maxim; Ritz, Adam

    2011-10-01

    We consider the sensitivity of fixed-target neutrino experiments at the luminosity frontier to light stable states, such as those present in models of MeV-scale dark matter. To ensure the correct thermal relic abundance, such states must annihilate via light mediators, which in turn provide an access portal for direct production in colliders or fixed targets. Indeed, this framework endows the neutrino beams produced at fixed-target facilities with a companion “dark matter beam,” which may be detected via an excess of elastic scattering events off electrons or nuclei in the (near-)detector. We study the high-luminosity proton fixed-target experiments at LSND and MiniBooNE, and determine that the ensuing sensitivity to light dark matter generally surpasses that of other direct probes. For scenarios with a kinetically-mixed U(1)' vector mediator of mass mV, we find that a large volume of parameter space is excluded for mDM˜1-5MeV, covering vector masses 2mDM≲mV≲mη and a range of kinetic mixing parameters reaching as low as κ˜10-5. The corresponding MeV-scale dark matter scenarios motivated by an explanation of the galactic 511 keV line are thus strongly constrained.

  6. Naturally light Dirac neutrino in Left-Right Symmetric Model

    Energy Technology Data Exchange (ETDEWEB)

    Borah, Debasish [Department of Physics, Indian Institute of Technology Guwahati, Assam-781039 (India); Dasgupta, Arnab, E-mail: dborah@iitg.ernet.in, E-mail: arnab.d@iopb.res.in [Institute of Physics, HBNI, Sachivalaya Marg, Bhubaneshwar-751005 (India)

    2017-06-01

    We study the possibility of generating tiny Dirac masses of neutrinos in Left-Right Symmetric Model (LRSM) without requiring the existence of any additional symmetries. The charged fermions acquire masses through a universal seesaw mechanism due to the presence of additional vector like fermions. The neutrinos acquire a one-loop Dirac mass from the same additional vector like charged leptons without requiring any additional discrete symmetries. The model can also be extended by an additional Z {sub 2} symmetry in order to have a scotogenic version of this scenario predicting a stable dark matter candidate. We show that the latest Planck upper bound on the effective number of relativistic degrees of freedom N {sub eff}=3.15 ± 0.23 tightly constrains the right sector gauge boson masses to be heavier than 3.548 TeV . This bound on gauge boson mass also affects the allowed values of right scalar doublet dark matter mass from the requirement of satisfying the Planck bound on dark matter relic abundance. We also discuss the possible implications of such a scenario in charged lepton flavour violation and generating observable electric dipole moment of leptons.

  7. Nonlinear Dynamics of the Cosmic Neutrino Background

    Science.gov (United States)

    Inman, Derek

    At least two of the three neutrino species are known to be massive, but their exact masses are currently unknown. Cosmic neutrinos decoupled from the rest of the primordial plasma early on when the Universe was over a billion times hotter than it is today. These relic particles, which have cooled and are now non-relativistic, constitute the Cosmic Neutrino Background and permeate the Universe. While they are not observable directly, their presence can be inferred by measuring the suppression of the matter power spectrum. This suppression is a linear effect caused by the large thermal velocities of neutrinos, which prevent them from collapsing gravitationally on small scales. Unfortunately, it is difficult to measure because of degeneracies with other cosmological parameters and biases arising from the fact that we typically observe point-like galaxies rather than a continous matter field. It is therefore important to look for new effects beyond linear suppression that may be more sensitive to neutrinos. This thesis contributes to the understanding of the nonlinear dynamics of the cosmological neutrino background in the following ways: (i) the development of a new injection scheme for neutrinos in cosmological N-body simulations which circumvents many issues associated with simulating neutrinos at large redshifts, (ii) the numerical study of the relative velocity field between cold dark matter and neutrinos including its reconstruction from density fields, (iii) the theoretical description of neutrinos as a dispersive fluid and its use in modelling the nonlinear evolution of the neutrino density power spectrum, (iv) the derivation of the dipole correlation function using linear response which allows for the Fermi-Dirac velocity distribution to be properly included, and (v) the numerical study and detection of the dipole correlation function in the TianNu simulation. In totality, this thesis is a comprehensive study of neutrino density and velocity fields that may

  8. Neutrino masses and neutrino oscillations

    CERN Document Server

    Di Lella, L

    2000-01-01

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

  9. GALAXY CLUSTER RADIO RELICS IN ADAPTIVE MESH REFINEMENT COSMOLOGICAL SIMULATIONS: RELIC PROPERTIES AND SCALING RELATIONSHIPS

    International Nuclear Information System (INIS)

    Skillman, Samuel W.; Hallman, Eric J.; Burns, Jack O.; Smith, Britton D.; O'Shea, Brian W.; Turk, Matthew J.

    2011-01-01

    Cosmological shocks are a critical part of large-scale structure formation, and are responsible for heating the intracluster medium in galaxy clusters. In addition, they are capable of accelerating non-thermal electrons and protons. In this work, we focus on the acceleration of electrons at shock fronts, which is thought to be responsible for radio relics-extended radio features in the vicinity of merging galaxy clusters. By combining high-resolution adaptive mesh refinement/N-body cosmological simulations with an accurate shock-finding algorithm and a model for electron acceleration, we calculate the expected synchrotron emission resulting from cosmological structure formation. We produce synthetic radio maps of a large sample of galaxy clusters and present luminosity functions and scaling relationships. With upcoming long-wavelength radio telescopes, we expect to see an abundance of radio emission associated with merger shocks in the intracluster medium. By producing observationally motivated statistics, we provide predictions that can be compared with observations to further improve our understanding of magnetic fields and electron shock acceleration.

  10. The number density of a charged relic

    International Nuclear Information System (INIS)

    Berger, C.F.; Kraml, S.; Palorini, F.

    2008-07-01

    We investigate scenarios in which a charged, long-lived scalar particle decouples from the primordial plasma in the Early Universe. We compute the number density at time of freeze-out considering both the cases of abelian and non-abelian interactions and including the effect of Sommerfeld enhancement at low initial velocity. We also discuss as extreme case the maximal cross section that fulfils the unitarity bound. We then compare these number densities to the exotic nuclei searches for stable relics and to the BBN bounds on unstable relics and draw conclusions for the cases of a stau or stop NLSP in supersymmetric models with a gravitino or axino LSP. (orig.)

  11. The number density of a charged relic

    Energy Technology Data Exchange (ETDEWEB)

    Berger, C.F. [Massachusetts Institute of Technology, Cambridge, MA (United States). Center for Theoretical Physics]|[California Univ., Santa Barbara, CA (United States). Kavli Inst. for Theoretical Physics; Covi, L. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Kraml, S. [CNRS/IN2P3, Grenoble (France). Lab. de Physique Subatomique et de Cosmologie; Palorini, F. [Lyon Univ., UCBL, CNRS/IN2P3, Villeurbanne (France). IPN de Lyon

    2008-07-15

    We investigate scenarios in which a charged, long-lived scalar particle decouples from the primordial plasma in the Early Universe. We compute the number density at time of freeze-out considering both the cases of abelian and non-abelian interactions and including the effect of Sommerfeld enhancement at low initial velocity. We also discuss as extreme case the maximal cross section that fulfils the unitarity bound. We then compare these number densities to the exotic nuclei searches for stable relics and to the BBN bounds on unstable relics and draw conclusions for the cases of a stau or stop NLSP in supersymmetric models with a gravitino or axino LSP. (orig.)

  12. Effective theories for Dark Matter interactions and the neutrino portal paradigm

    Energy Technology Data Exchange (ETDEWEB)

    Macías, Vannia González; Wudka, José [Department of Physics & Astronomy, University of California Riverside,University Av., Riverside, California 92521-0413 (United States)

    2015-07-29

    In this article we discuss a general effective-theory description of a multi-component dark sector with an unspecified non-trivial symmetry and its interactions with the Standard Model generated by the exchange of heavy mediators. We then categorize the relevant effective operators given the current experimental sensistivity where the underlying theory is weakly coupled and renormalizable, with neutral mediators: either scalars or fermions. An interesting scenario resulting from this categorization is the neutrino portal, where only fermion mediators are present, and where the dark sector consists of fermions and scalars such that the lightest dark particle is a fermion, this scenario is characterized by having naturally suppressed couplings of the DM to all SM particles except the neutrinos and has received little attention in the literature. We find that there is a wide region in parameter space allowed by the current experimental constraints (relic abundance, direct and indirect detection limits); the cleanest signature of this paradigm is the presence of monochromatic neutrino lines with energy equal to that of the DM mass, but experimental sensitivity would have to be improved significantly before this can be probed.

  13. Neutrino physics

    CERN Document Server

    Hernandez, P.

    2016-01-01

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

  14. Neutrino astrophysics

    International Nuclear Information System (INIS)

    Roulet, E.

    2001-01-01

    A general overview of neutrino physics and astrophysics 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 introduce the main scenarios to provide them a mass. The present bounds and the positive indications in favor of non-zero neutrino masses are discussed, including the recent results on atmospheric and solar neutrinos. The major role that neutrinos play in astrophysics and cosmology is illustrated. (author)

  15. The 'relics of Joan of Arc'

    DEFF Research Database (Denmark)

    Charlier, P.; Poupon, J.; Eb, A.

    2010-01-01

    Archaeological remains can provide concrete cases, making it possible to develop, refine or validate medico-legal techniques. In the case of the so-called 'Joan of Arc's relics' (a group of bone and archaeological remains known as the 'Bottle of Chinon'), 14 specialists analysed the samples such ...

  16. Neutrino Physics

    CERN Document Server

    Barenboim, G.

    2014-12-10

    The Standard Model has been incredibly successful in predicting the outcome of almost all the experiments done up so far. In it, neutrinos are mass-less. However, in recent years we have accumulated evidence pointing to tiny masses for the neutrinos (as compared to the charged leptons). These masses allow neutrinos to change their flavour and oscillate. In these lectures I review the properties of neutrinos in and beyond the Standard Model.

  17. Los Neutrinos Los Neutrinos

    Directory of Open Access Journals (Sweden)

    Julián Félix

    2012-02-01

    Full Text Available From all the proposals to understand the structure of matter, and the way the natural world is conformed, the one about neutrinos is the most enigmatic, abstract, and foreign to immediate experience; however, this is the one that has delved more deeply over the nearly eighty years since it was formulated by Wolfgang Pauli –in 1930- as a radical proposition to understand nucleon decay, and the decay of other particles, without the violation of the principle of conservation of energy and momentum at subatomic level. This proposition has evolved through the years, and from Pauli’s original idea only the basic elements remain.This article contains the tale of the hypothesis of neutrinos, its early history, its evolution up to present day, and the efforts done nowadays to study them. In summary, this is the physics of neutrinos. De todas las propuestas para entender la estructura de la materia, y la conformación del mundo natural, los neutrinos es la más enigmática, abstracta, y ajena a la experiencia inmediata; sin embargo, es la que más hondo ha ido calando a lo largo de los ya casi ochenta años de haber sido formulada por Wolfgang Pauli –en el año 1930- como una medida radical para entender el decaimiento de los nucleones, y otras partículas, sin que se violara el principio de la conservación de la energía y del momento a nivel subatómico. La propuesta ha evolucionado a lo largo de los años, y de la idea original de Pauli ya sólo lo básico permanece. En este artículo está el relato de la hipótesis de los neutrinos, su historia primera, su evolución hasta el presente, los esfuerzos que en la actualidad se realizan para estudiarlos. En breve, ésta es la física de los neutrinos.

  18. Solar neutrinos

    International Nuclear Information System (INIS)

    Phillips, R.J.N.

    1987-09-01

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

  19. Sterile neutrino

    International Nuclear Information System (INIS)

    Anon.

    2007-01-01

    Paper deals with the information on the occurrence of the fields of the sterile neutrinos (the righthanded ones) mixed with the normal neutrinos (the lefthanded ones). Both the Max Plank Radioastronomy Institute and the Los Angeles University assumes that the occurrence of the keV mass sterile neutrinos may explain the dark matter nature, the fast rotation of the observed pulsars and the reionization processes. The issues associated with the possibility to record the sterile neutrinos were analyzed in the course of the Sterile Neutrinos in Astrophysics and Cosmology Workshop (Crans Montana, March 2006 [ru

  20. Research on Splicing Method of Digital Relic Fragment Model

    Science.gov (United States)

    Yan, X.; Hu, Y.; Hou, M.

    2018-04-01

    In the course of archaeological excavation, a large number of pieces of cultural relics were unearthed, and the restoration of these fragments was done manually by traditional arts and crafts experts. In this process, cultural relics experts often try to splice the existing cultural relics, and then use adhesive to stick together the fragments of correct location, which will cause irreversible secondary damage to cultural relics. In order to minimize such damage, the surveyors combine 3D laser scanning with computer technology, and use the method of establishing digital cultural relics fragments model to make virtual splicing of cultural relics. The 3D software on the common market can basically achieve the model translation and rotation, using this two functions can be achieved manually splicing between models, mosaic records after the completion of the specific location of each piece of fragments, so as to effectively reduce the damage to the relics had tried splicing process.

  1. Neutrino factories

    International Nuclear Information System (INIS)

    Dydak, F.

    2002-01-01

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

  2. Neutrinos today

    International Nuclear Information System (INIS)

    Pontecorvo, B.; Bilen'kij, S.

    1987-01-01

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

  3. Neutrino Factory

    CERN Document Server

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

    2014-01-01

    The properties of the neutrino provide a unique window on physics beyond that described by the standard model. The study of subleading effects in neutrino oscillations, and the race to discover CP-invariance violation in the lepton sector, has begun with the recent discovery that $\\theta_{13} > 0$. The measured value of $\\theta_{13}$ is large, emphasizing the need for a facility at which the systematic uncertainties can be reduced to the percent level. The neutrino factory, in which intense neutrino beams are produced from the decay of muons, has been shown to outperform all realistic alternatives and to be capable of making measurements of the requisite precision. Its unique discovery potential arises from the fact that only at the neutrino factory is it practical to produce high-energy electron (anti)neutrino beams of the required intensity. This paper presents the conceptual design of the neutrino factory accelerator facility developed by the European Commission Framework Programme 7 EURO$\

  4. Equilibrium thermodynamics and neutrino decoupling in quasi-metric cosmology

    Science.gov (United States)

    Østvang, Dag

    2018-05-01

    The laws of thermodynamics in the expanding universe are formulated within the quasi-metric framework. The quasi-metric cosmic expansion does not directly influence momenta of material particles, so the expansion directly cools null particles only (e.g., photons). Therefore, said laws differ substantially from their counterparts in standard cosmology. Consequently, all non-null neutrino mass eigenstates are predicted to have the same energy today as they had just after neutrino decoupling in the early universe. This indicates that the predicted relic neutrino background is strongly inconsistent with detection rates measured in solar neutrino detectors (Borexino in particular). Thus quasi-metric cosmology is in violent conflict with experiment unless some exotic property of neutrinos makes the relic neutrino background essentially undetectable (e.g., if all massive mass eigenstates decay into "invisible" particles over cosmic time scales). But in absence of hard evidence in favour of the necessary exotic neutrino physics needed to resolve said conflict, the current status of quasi-metric relativity has been changed to non-viable.

  5. Dark matter relics and the expansion rate in scalar-tensor theories

    Energy Technology Data Exchange (ETDEWEB)

    Dutta, Bhaskar; Jimenez, Esteban [Mitchell Institute for Fundamental Physics and Astronomy, Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States); Zavala, Ivonne, E-mail: dutta@physics.tamu.edu, E-mail: este1985@physics.tamu.edu, E-mail: e.i.zavalacarrasco@swansea.ac.uk [Department of Physics, Swansea University, Singleton Park, Swansea, SA2 8PP (United Kingdom)

    2017-06-01

    We study the impact of a modified expansion rate on the dark matter relic abundance in a class of scalar-tensor theories. The scalar-tensor theories we consider are motivated from string theory constructions, which have conformal as well as disformally coupled matter to the scalar. We investigate the effects of such a conformal coupling to the dark matter relic abundance for a wide range of initial conditions, masses and cross-sections. We find that exploiting all possible initial conditions, the annihilation cross-section required to satisfy the dark matter content can differ from the thermal average cross-section in the standard case. We also study the expansion rate in the disformal case and find that physically relevant solutions require a nontrivial relation between the conformal and disformal functions. We study the effects of the disformal coupling in an explicit example where the disformal function is quadratic.

  6. Neutrino sunshine

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    Full text: On 10 June 1992, at the Neutrino 92 meeting in Grenada, Spain, Till Kirsten of Heidelberg's Max Planck Institute reported that neutrinos from sunshine had been seen. Most of the energy pumped out by the Sun comes from the fusion of protons into alpha particles, a process which also liberates neutrinos. While it takes about a million years for radiant energy formed in the deep interior of the Sun to fight its way to the surface, the highly penetrating neutrinos emerge almost immediately. It was in 1970 that Ray Davis and his team began taking data with a tank containing 615 tons of perchloroethylene (dry cleaning fluid) 1500 metres underground in the Homestake gold mine, South Dakota. The observed signal is consistently smaller than what is expected. This 'solar neutrino problem' was confirmed by the Kamioka mine experiment in Japan, looking at the Cherenkov light released by neutrino interactions in some 700 tons of water. However these experiments are only sensitive to a tiny high energy tail of the solar neutrino spectrum, and to understand what is going on needs measurements of the primary neutrinos from proton fusion. To get at these neutrinos, two large new detectors, using gallium and sensitive to these lower energy particles, have been built and commissioned in the past few years. The detectors are SAGE ('Soviet' American Gallium Experiment) in the Baksan Neutrino Observatory in the Caucasus, and Gallex, a team from France, Germany, Israel, Italy and the US in the Italian Gran Sasso underground Laboratory. At Grenada, Kirsten reported unmistakable signs of solar neutrinos of proton origin recorded in Gallex. SAGE and Gallex do not yet have enough data to unambiguously fix the level of primary solar neutrinos reaching the Earth, and the interpretation of the interim results tends to be subjective. However after 23 years of conditioning through watching the solar neutrinos' high energy tail, the prospect of a neutrino

  7. Massive neutrinos and cosmology

    International Nuclear Information System (INIS)

    Shandarin, S.F.

    1991-01-01

    This paper discussed the importance of the consequences of a nonzero neutrino rest mass on cosmology, perhaps, first recognized by Gershtein and Zeldovich, after the discover of the 3-K microwave background radiation MBR. Since the first works on the primordial synthesis of 4 He, it has been known that additional neutrino species increase the rate of expansion of the universe during the epoch of the primordial nucleosynthesis, which increases the yield of 4 He. Combining the results of the theory with astronomical measurements of the 4 He abundance and the estimate of the mass density of MBR, Shvartsman suggested the upper limit on the mass density of all relativistic matter at that epoch: ρ rel ≤ 5ρ MBR which eventually became the upper limit for the number of neutrino species: N ν ≤ 7. At that time, the constraints based on cosmological arguments were much stronger than one based on laboratory experiments

  8. Research and design progress of the Jinping Neutrino Experiment

    Science.gov (United States)

    Wang, Zhe

    2018-01-01

    Thanks to the 2400 m overburden and the long distance to commercial reactors, the China Jinping Underground Laboratory (CJPL) is an ideal site for low background neutrino experiments. The Jinping Neutrino Experiment will perform an in-depth research on solar neutrinos, geo-neutrinos and supernova relic neutrinos. Many efforts were devoted to the R&D of the experimental proposal. A new type of liquid scintillator, with high light-yield and Cherenkov and scintillation separation capability, is being developed. The assay and selection of low radioactive stainless-steel (SST) was carried out. A wide field-of-view of 90 degree and high-geometry-efficiency of 98% light concentrator is developed. At the same time, a 1-ton prototype is constructed and placed underground at Jinping laboratory. The simulation and analysis software, electromagnetic calorimeter function, rock damage zone simulation will also be introduced briefly.

  9. NEUTRINO MASS

    OpenAIRE

    Kayser, Boris

    1988-01-01

    This is a review article about the most recent developments on the field of neutrino mass. The first part of the review introduces the idea of neutrino masses and mixing angles, summarizes the most recent experimental data then discusses the experimental prospects and challenges in this area. The second part of the review discusses the implications of these results for particle physics and cosmology, including the origin of neutrino mass, the see-saw mechanism and sequential dominance, and la...

  10. Neutrino masses

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    Postulated in the early days of quantum mechanics by Wolfgang Pauli to make energy-momentum conservation in nuclear beta decay come out right, the neutrino has never strayed far from physicists' attention. The Moriond Workshop on Massive Neutrinos in Particle Physics and Astrophysics held recently in the French Alps showed that more than half a century after Pauli's prediction, the neutrino stubbornly refuses to yield up all its secrets

  11. Neutrino masses

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1986-04-15

    Postulated in the early days of quantum mechanics by Wolfgang Pauli to make energy-momentum conservation in nuclear beta decay come out right, the neutrino has never strayed far from physicists' attention. The Moriond Workshop on Massive Neutrinos in Particle Physics and Astrophysics held recently in the French Alps showed that more than half a century after Pauli's prediction, the neutrino stubbornly refuses to yield up all its secrets.

  12. Neutrino mass

    International Nuclear Information System (INIS)

    Robertson, R.G.H.

    1992-01-01

    Despite intensive experimental work since the neutrino's existence was proposed by Pauli 60 years ago, and its first observation by Reines and Cowan almost 40 years ago, the neutrino's fundamental properties remain elusive. Among those properties are the masses of the three known flavors, properties under charge conjugation, parity and time-reversal, and static and dynamic electromagnetic moments. Mass is perhaps the most fundamental, as it constrains the other properties. The present status of the search for neutrino mass is briefly reviewed

  13. Neutrino mass and the origin of galactic magnetic fields

    International Nuclear Information System (INIS)

    Enqvist, K.; Semikoz, V.; Shukurov, A.; Sokoloff, D.

    1993-01-01

    We compare two constraints on the strength of the cosmological primordial magnetic field: the one following from the restrictions on the Dirac neutrino spin flip in the early Universe, and another one based on the galactic dynamo theory for the Milky Way (presuming that the seed magnetic field has a relic origin). Since the magnetic field facilitates transitions between left- and right-handed neutrino states, thereby affecting 4 He production at primordial nucleosynthesis, we can obtain a guaranteed upper limit on the strength of the relic magnetic field in the protogalaxy, B c approx-lt 4x10 -9 --3x10 -13 G, depending on the neutrino magnetic moment, if we adopt the MSW explanation of the GALLEX results. On the other hand, models of the dynamo in the Milky Way indicate that the seed magnetic field should be at least 10 -11 --10 -13 G at the protogalaxy scale L=100 kpc. These upper and lower limiting ranges are marginally consistent provided the electron neutrino mass is below 0.3 eV. The results apply to a relic magnetic field produced in the early Universe by any causal mechanism before the nucleosynthesis

  14. Eclipsed neutrinos

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-05-02

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

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

    Science.gov (United States)

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

    2014-05-01

    Core-collapse supernovae eject huge amount of flux of energetic neutrinos which affect explosive nucleosynthesis of rare isotopes like 7Li, 11B, 92Nb, 138La and Ta and r-process elements. Several isotopes depend strongly on the neutrino flavor oscillation due to the Mikheyev-Smirnov-Wolfenstein (MSW) effect. We here discuss how to determine the neutrino temperatures and propose a method to determine still unknown neutrino oscillation parameters, mass hierarchy and θ13, simultaneously. Combining the recent experimental constraints on θ13 with isotopic ratios of the light elements discovered in presolar grains from the Murchison meteorite, we show that our method suggests at a marginal preference for an inverted neutrino mass hierarchy. We also discuss supernova relic neutrinos that may indicate the softness of the equation of state (EoS) of nuclear matter as well as adiabatic conditions of the neutrino oscillation.

  17. The Shroud of Turin: Relic or icon?

    International Nuclear Information System (INIS)

    Dale, W.S.A.

    1987-01-01

    The Shroud of Turin, a linen cloth on which appear the imprints of the front and back of a crucified man, can be historically traced to ca. 1354 A.D. Many believe it to be a true relic of the Passion of Christ. Many others regard it as a fake. This paper suggests a third alternative, that it is an icon dating from the 11th century. If future scientific tests, of which radiocarbon dating will be the most important, support this theory, the Shroud of Turin may well be recognized as one of the masterpieces of Christian art. (orig.)

  18. Relic gravitational waves and extended inflation

    International Nuclear Information System (INIS)

    Turner, M.S.; Wilczek, F.

    1990-01-01

    In extended inflation, a new version of inflation where the transition from an inflationary to a radiation-dominated Universe is accomplished by bubble nucleation, bubble collisions supply a potent---and potentially detectable---source of gravitational waves. The energy density in relic gravitons from bubble collisions is expected to be about 10 -5 of closure density. Their characteristic wavelength depends upon the reheating temperature T RH: λ∼(10 4 cm)[(10 14 GeV)/T RH ]. If black holes are produced by bubble collisions, they will evaporate producing shorter-wavelength gravitons

  19. Neutrino Oscillations

    Indian Academy of Sciences (India)

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

  20. Report of the Solar and Atmospheric Neutrino Working Group

    International Nuclear Information System (INIS)

    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.

    2004-01-01

    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

  1. Bound-state formation for thermal relic dark matter and unitarity

    International Nuclear Information System (INIS)

    Harling, Benedict von; Petraki, Kalliopi

    2014-01-01

    We show that the relic abundance of thermal dark matter annihilating via a long-range interaction, is significantly affected by the formation and decay of dark matter bound states in the early universe, if the dark matter mass is above a few TeV . We determine the coupling required to obtain the observed dark matter density, taking into account both the direct 2-to-2 annihilations and the formation of bound states, and provide an analytical fit. We argue that the unitarity limit on the inelastic cross-section is realized only if dark matter annihilates via a long-range interaction, and we determine the upper bound on the mass of thermal-relic dark matter to be about 197 (139) TeV for (non)-self-conjugate dark matter

  2. Heavy Right-Handed Neutrino Dark Matter and PeV Neutrinos at IceCube

    Science.gov (United States)

    Bhupal Dev, P. S.; Kazanas, D.; Mohapatra, R. N.; Teplitz, V. L.; Zhang, Yongchao

    2016-01-01

    We discuss a simple non-supersymmetric model based on the electroweak gauge group SU(2) (sub L) times SU(2) prime times U(1) (Sub B-L) where the lightest of the right-handed neutrinos, which are part of the leptonic doublet of SU(2) prime, play the role of a long-lived unstable dark matter with mass in the multi-Peta-electronvolt range. We use a resonant s-channel annihilation to obtain the correct thermal relic density and relax the unitarity bound on dark matter mass. In this model, there exists a 3-body dark matter decay mode producing tau leptons and neutrinos, which could be the source for the Peta-electronvolt cascade events observed in the IceCube experiment. The model can be tested with more precise flavor information of the highest-energy neutrino events in future data.

  3. Heavy right-handed neutrino dark matter and PeV neutrinos at IceCube

    Energy Technology Data Exchange (ETDEWEB)

    Dev, P.S. Bhupal [Max-Planck-Institut für Kernphysik,Saupfercheckweg 1, D-69117 Heidelberg (Germany); Kazanas, D. [Astrophysics Science Division, NASA Goddard Space Flight Center,Greenbelt, MD 20771 (United States); Mohapatra, R.N. [Maryland Center for Fundamental Physics, Department of Physics, University of Maryland,College Park, MD 20742 (United States); Teplitz, V.L. [Astrophysics Science Division, NASA Goddard Space Flight Center,Greenbelt, MD 20771 (United States); Department of Physics, Southern Methodist University,Dallas, TX 75205 (United States); Zhang, Yongchao [Service de Physique Théorique, Université Libre de Bruxelles,Boulevard du Triomphe, CP225, 1050 Brussels (Belgium); School of Physics, Sun Yat-Sen University,Guangzhou 510275 (China)

    2016-08-17

    We discuss a simple non-supersymmetric model based on the electroweak gauge group SU(2){sub L}×SU(2){sup ′}×U(1){sub B−L} where the lightest of the right-handed neutrinos, which are part of the leptonic doublet of SU(2){sup ′}, play the role of a long-lived unstable dark matter with mass in the multi-PeV range. We use a resonant s-channel annihilation to obtain the correct thermal relic density and relax the unitarity bound on dark matter mass. In this model, there exists a 3-body dark matter decay mode producing tau leptons and neutrinos, which could be the source for the PeV cascade events observed in the IceCube experiment. The model can be tested with more precise flavor information of the highest-energy neutrino events in future data.

  4. Solar neutrinos

    International Nuclear Information System (INIS)

    Schatzman, E.

    1983-01-01

    The solar energy is produced by a series of nuclear reactions taking place in the deep interior of the sun. Some of these reactions produce neutrinos which may be detected, the proper detection system being available. The results of the Davis experiment (with 37 Cl) are given, showing a deficiency in the solar neutrino flux. The relevant explanation is either a property of the neutrino or an important change in the physics of the solar models. The prospect of a new experiment (with 71 Ga) is important as it will decide which of the two explanations is correct [fr

  5. Neutrino Emission from Supernovae

    Science.gov (United States)

    Janka, Hans-Thomas

    Supernovae are the most powerful cosmic sources of MeV neutrinos. These elementary particles play a crucial role when the evolution of a massive star is terminated by the collapse of its core to a neutron star or a black hole and the star explodes as supernova. The release of electron neutrinos, which are abundantly produced by electron captures, accelerates the catastrophic infall and causes a gradual neutronization of the stellar plasma by converting protons to neutrons as dominant constituents of neutron star matter. The emission of neutrinos and antineutrinos of all flavors carries away the gravitational binding energy of the compact remnant and drives its evolution from the hot initial to the cold final state. The absorption of electron neutrinos and antineutrinos in the surroundings of the newly formed neutron star can power the supernova explosion and determines the conditions in the innermost supernova ejecta, making them an interesting site for the nucleosynthesis of iron-group elements and trans-iron nuclei.

  6. Neutrino sunshine

    Energy Technology Data Exchange (ETDEWEB)

    Fraser, Gordon

    1992-09-15

    Most of the Sun's energy comes from the fusion of protons into deuterium. Sunshine is necessary for life, but the first evidence for the neutrinos which accompany and explain this basic process still makes science history.

  7. Supernova neutrinos

    International Nuclear Information System (INIS)

    John Beacom

    2003-01-01

    We propose that neutrino-proton elastic scattering, ν + p → ν + p, can be used for the detection of supernova neutrinos. Though the proton recoil kinetic energy spectrum is soft, with T p ≅ 2E ν 2 /M p , and the scintillation light output from slow, heavily ionizing protons is quenched, the yield above a realistic threshold is nearly as large as that from (bar ν) e + p → e + + n. In addition, the measured proton spectrum is related to the incident neutrino spectrum, which solves a long-standing problem of how to separately measure the total energy release and temperature of ν μ , ν τ , (bar ν) μ , and (bar ν) τ . The ability to detect this signal would give detectors like KamLAND and Borexino a crucial and unique role in the quest to detect supernova neutrinos

  8. Neutrino cosmology

    CERN Document Server

    Lesgourgues, Julien; Miele, Gennaro; Pastor, Sergio

    2013-01-01

    The role that neutrinos have played in the evolution of the Universe is the focus of one of the most fascinating research areas that has stemmed from the interplay between cosmology, astrophysics and particle physics. In this self-contained book, the authors bring together all aspects of the role of neutrinos in cosmology, spanning from leptogenesis to primordial nucleosynthesis, their role in CMB and structure formation, to the problem of their direct detection. The book starts by guiding the reader through aspects of fundamental neutrino physics, such as the standard cosmological model and the statistical mechanics in the expanding Universe, before discussing the history of neutrinos in chronological order from the very early stages until today. This timely book will interest graduate students and researchers in astrophysics, cosmology and particle physics, who work with either a theoretical or experimental focus.

  9. Neutrino sunshine

    International Nuclear Information System (INIS)

    Fraser, Gordon

    1992-01-01

    Most of the Sun's energy comes from the fusion of protons into deuterium. Sunshine is necessary for life, but the first evidence for the neutrinos which accompany and explain this basic process still makes science history

  10. Neutrino overview

    International Nuclear Information System (INIS)

    Haxton, W.C.

    1994-01-01

    I discuss some of the open issues in neutrino physics, emphasizing areas of intersection with astrophysics, that occupied the participants of the Snowmass Workshop on Nuclear and Particle Astrophysics and Cosmology in the Next Millenium

  11. Neutrino masses and oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Smirnov, A Yu

    1996-11-01

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

  12. Scalar modes of the relic gravitons

    CERN Document Server

    Giovannini, Massimo

    2015-01-01

    In conformally flat background geometries the long wavelength gravitons can be described in the fluid approximation and they induce scalar fluctuations both during inflation and in the subsequent radiation-dominated epoch. While this effect is minute and suppressed for a de Sitter stage of expansion, the fluctuations of the energy-momentum pseudo-tensor of the graviton fluid lead to curvature perturbations that increase with time all along the post-inflationary evolution. An explicit calculation of these effects is presented for a standard thermal history and it is shown that the growth of the curvature perturbations caused by the long wavelength modes is approximately compensated by the slope of the power spectra of the energy density, pressure and anisotropic stress of the relic gravitons.

  13. Relic gravitational waves and extended inflation

    International Nuclear Information System (INIS)

    Turner, M.S.; Wilczek, F.

    1990-08-01

    In extended inflation, a new version of inflation where the transition from the false-vacuum phase to a radiation-dominated Universe is accomplished by bubble nucleation and percolation, bubble collisions supply a potent-and potentially detectable-source of gravitational waves. The present energy density in relic gravity waves from bubble collisions is expected to be about 10(exp -5) of closure density-many orders of magnitude greater than that of the gravity waves produced by quantum fluctuations. Their characteristic wavelength depends upon the reheating temperature T(sub RH): lambda is approximately 10(exp 4) cm (10(exp 14) GeV/T(sub RH)). If large numbers of black holes are produced, a not implausible outcome, they will evaporate producing comparable amounts of shorter wavelength waves, lambda is approximately 10(exp -6) cm (T(sub RH)/10(exp 14) GeV)

  14. The refractive index of relic gravitons

    CERN Document Server

    Giovannini, Massimo

    2016-01-01

    The dynamical evolution of the refractive index of the tensor modes of the geometry produces a specific class of power spectra characterized by a blue (i.e. slightly increasing) slope which is directly determined by the competition of the slow-roll parameter and of the rate of variation of the refractive index. Throughout the conventional stages of the inflationary and post-inflationary evolution, the microwave background anisotropies measurements, the pulsar timing limits and the big-bang nucleosythesis constraints set stringent bounds on the refractive index and on its rate of variation. Within the physically allowed region of the parameter space the cosmic background of relic gravitons leads to a potentially large signal for the ground based detectors (in their advanced version) and for the proposed space-borne interferometers. Conversely, the lack of direct detection of the signal will set a qualitatively new bound on the dynamical variation of the refractive index.

  15. Supernova neutrino detection

    International Nuclear Information System (INIS)

    Selvi, M.

    2005-01-01

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

  16. Gravitino dark matter from increased thermal relic particles

    International Nuclear Information System (INIS)

    Okada, Nobuchika; Seto, Osamu

    2008-01-01

    We investigate the so-called superWIMP scenario with the gravitino as the lightest supersymmetric particle (LSP) in the context of nonstandard cosmology, in particular, brane world cosmology. As a candidate of the next-to-LSP (NLSP), we examine the slepton and the sneutrino. Brane world cosmological effects dramatically enhance the relic density of the slepton or sneutrino NLSP, so that the NLSP with mass of order 100 GeV can provide the correct abundance of gravitino dark matter through its decay. We find that with an appropriate five-dimensional Planck mass, this scenario can be realized consistently with the constraints from big bang nucleosynthesis for both NLSP candidates of the slepton and the sneutrino. The big bang nucleosynthesis constraints for the slepton NLSP are more stringent than that for the sneutrino; as the result, the gravitino must be rather warm in the slepton NLSP case. The energy density of the gravitino produced by thermal scattering is highly suppressed and negligible due to the brane world cosmological effects

  17. Neutrino oscillations in dense neutrino gases

    International Nuclear Information System (INIS)

    Samuel, S.

    1993-01-01

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

  18. Neutrino astronomy with supernova neutrinos

    Science.gov (United States)

    Brdar, Vedran; Lindner, Manfred; Xu, Xun-Jie

    2018-04-01

    Modern neutrino facilities will be able to detect a large number of neutrinos from the next Galactic supernova. We investigate the viability of the triangulation method to locate a core-collapse supernova by employing the neutrino arrival time differences at various detectors. We perform detailed numerical fits in order to determine the uncertainties of these time differences for the cases when the core collapses into a neutron star or a black hole. We provide a global picture by combining all the relevant current and future neutrino detectors. Our findings indicate that in the scenario of a neutron star formation, supernova can be located with precision of 1.5 and 3.5 degrees in declination and right ascension, respectively. For the black hole scenario, sub-degree precision can be reached.

  19. Solar neutrino

    Energy Technology Data Exchange (ETDEWEB)

    Sugimoto, D [Tokyo Univ. (Japan). Coll. of General Education

    1975-01-01

    The measurement of solar neutrino was performed by using the reaction /sup 37/cl+..nu..sub(e)..-->../sup 37/Ar+e/sup -/ by Davis et al. The argon gas produced through the above mentioned reaction in a tank containing 610 ton of C/sub 2/Cl/sub 4/ was collected and measured. The rate of production of /sup 37/Ar was 0.13+-0.20/day, and the net production rate by the solar neutrino was 0.06+-0.20/day, being corrected for background. This value corresponds to 0.5+-1.0 SNU. Theoretical calculation with the model of spherically symmetric solar development gave an expected value of 5.6 SNU, which is in contradiction with the experimental value. Reason of this discrepancy was considered. The possibility of decay of neutrino to the other particles with weak interaction is very slight. Various models of the sun were investigated, but the results were still inconsistent with the experiment. The mixing of matters in the sun may cause the reduction of neutrino. If He gas comes to the center of the sun by mixing, the reaction, /sup 3/He+/sup 3/He, progresses excessively at the center, and it produces the expansion of the core of the sun. Then, the temperature drops and the neutrino is reduced. Various models which can explain the neutrino of less than ISNU have been presented. However, other theory says that the reduction of neutrino is not expected even if the mixing is considered. A problem concerning the mixing is whether the thermal instability which causes the mixing exists. (Kato, T.).

  20. Neutrinos in cosmology

    International Nuclear Information System (INIS)

    Tayler, R.J.

    1983-01-01

    The standard model of the hot big bang cosmological theory, which appears to be in agreement, at least qualitatively, with the observed properties of the Universe, assumes that the early Universe was homogeneous and isotropic and that it has been continuously expanding from a state characterized by very high temperature and density, where matter and radiation were to a good approximation in a state of thermodynamic equilibrium. In this standard model, it is assumed that baryon number, charge number and the various lepton numbers are all conserved. Only the baryon number is non-zero and this, expressed as the ratio of the net number of baryons (baryons minus antibaryons) to the number of photons per unit volume is the undefined parameter in the model. The author discusses the importance of knowing how many types of neutrinos there are with regard to the He 4 abundance, and the implication of a small, non-zero neutrino mass. (Auth.)

  1. Experimental neutrino physics

    CERN Document Server

    Link, Jonathan M

    2018-01-01

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

  2. Sterile Neutrinos, Dark Matter, and Pulsar Velocities in Models with a Higgs Singlet

    International Nuclear Information System (INIS)

    Kusenko, Alexander

    2006-01-01

    We identify the range of parameters for which the sterile neutrinos can simultaneously explain the cosmological dark matter and the observed velocities of pulsars. To satisfy all cosmological bounds, the relic sterile neutrinos must be produced sufficiently cold. This is possible in a class of models with a gauge-singlet Higgs boson coupled to the neutrinos. Sterile dark matter can be detected by the x-ray telescopes. The presence of the singlet in the Higgs sector can be tested at the CERN Large Hadron Collider

  3. Neutrinos and Big Bang Nucleosynthesis

    Directory of Open Access Journals (Sweden)

    Gary Steigman

    2012-01-01

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

  4. Stochastic backgrounds of relic gravitons: a theoretical appraisal

    CERN Document Server

    Giovannini, Massimo

    2010-01-01

    Stochastic backgrounds or relic gravitons, if ever detected, will constitute a prima facie evidence of physical processes taking place during the earliest stages of the evolution of the plasma. The essentials of the stochastic backgrounds of relic gravitons are hereby introduced and reviewed. The pivotal observables customarily employed to infer the properties of the relic gravitons are discussed both in the framework of the $\\Lambda$CDM paradigm as well as in neighboring contexts. The complementarity between experiments measuring the polarization of the Cosmic Microwave Background (such as, for instance, WMAP, Capmap, Quad, Cbi, just to mention a few) and wide band interferometers (e.g. Virgo, Ligo, Geo, Tama) is emphasized. While the analysis of the microwave sky strongly constrains the low-frequency tail of the relic graviton spectrum, wide-band detectors are sensitive to much higher frequencies where the spectral energy density depends chiefly upon the (poorly known) rate of post-inflationary expansion.

  5. Neutrino mass and the solar neutrino problem

    International Nuclear Information System (INIS)

    Wolfenstein, L.

    1987-01-01

    Theoretical ideas about neutrino mass based on grand-unified theories are reviewed. These give the see-saw formula in which neutrino mass is inversely proportional to a large mass scale M. For M between 10/sup 11/ and 10/sup 15/ Gev the study of solar neutrinos appears to be the best probe of neutrino masses and mixings

  6. Neutrino clouds

    International Nuclear Information System (INIS)

    Stephenson Jr, G.J.; McKellar, B.H.J.

    1997-01-01

    We consider the possibility that neutrinos are coupled very weakly to an extremely light scalar boson. We first analyze the simple problem of one generation of neutrino and show that, for ranges of parameters that are allowed by existing data, such a system can have serious consequences for the evolution of stars and could impact precision laboratory measurements. We discuss the extension to more generations and show that the general conclusion remains viable. Finally, we note that, should such a scalar field be present, experiments give information about effective masses, not the masses that arise in unified field theories. (authors). 23 refs., 9 figs

  7. Neutrino clouds

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-06-01

    We consider the possibility that neutrinos are coupled very weakly to an extremely light scalar boson. We first analyze the simple problem of one generation of neutrino and show that, for ranges of parameters that are allowed by existing data, such a system can have serious consequences for the evolution of stars and could impact precision laboratory measurements. We discuss the extension to more generations and show that the general conclusion remains viable. Finally, we note that, should such a scalar field be present, experiments give information about effective masses, not the masses that arise in unified field theories. (authors). 23 refs., 9 figs.

  8. Neutrino Telescope

    International Nuclear Information System (INIS)

    Coelin Baldo, Milla

    2009-01-01

    The present volume contains the proceedings of the 13. International Workshop on 'Neutrino Telescope', 17. of the series 'Un altro modo di guardare il cielo', held in Venice at the 'Istituto Veneto di Scienze, Lettere ed Arti' from March 10 to March 13, 2009. This series started in Venice 21 years ago, in 1988, motivated by the growing interest in the exciting field of the neutrino physics and astrophysics, with the aim to bring together experimentalists and theorists and encourage discussion on the most recent results and to chart the direction of future researchers.

  9. Relic gravitational waves in the accelerating Universe

    International Nuclear Information System (INIS)

    Zhang Yang; Yuan Yefei; Zhao Wen; Chen Yingtian

    2005-01-01

    Recent observations have indicated that the Universe at the present stage is in an accelerating expansion, a process that has great implications. We evaluate the spectrum of relic gravitational waves in the current accelerating Universe and find that there are new features appearing in the resulting spectrum as compared to the decelerating models. In the low-frequency range the peak of the spectrum is now located at a frequency ν E ∼ (OMEGA m /OMEGA Λ ) 1/3 ν H , where ν H is the Hubble frequency, and there appears a new segment of spectrum between ν E and ν H . In all other intervals of frequencies ≥ν H , the spectral amplitude acquires an extra factor (OMEGA m /OMEGA Λ ), due to the current acceleration; otherwise the shape of the spectrum is similar to that in the decelerating models. The recent WMAP result of CMB anisotropies is used to normalize the amplitude for gravitational waves. The slope of the power spectrum depends sensitively on the scale factor a(τ) ∝ vertical bar τ vertical bar 1+β during the inflationary stage with β = -2 for the exact de Sitter space. With increasing β, the resulting spectrum is tilted to be flatter with more power at high frequencies, and the sensitivity of the second science run of the LIGO detectors puts a restriction on the parameter β ≤ -1.8. We also give a numerical solution which confirms these features

  10. Relic gravity waves from braneworld inflation

    International Nuclear Information System (INIS)

    Sahni, Varun; Sami, M.; Souradeep, Tarun

    2002-01-01

    We discuss a scenario in which extra dimensional effects allow a scalar field with a steep potential to play the dual role of the inflaton as well as dark energy (quintessence). The post-inflationary evolution of the universe in this scenario is generically characterized by a 'kinetic regime' during which the kinetic energy of the scalar field greatly exceeds its potential energy resulting in a 'stiff' equation of state for scalar field matter P φ ≅ρ φ . The kinetic regime precedes the radiation dominated epoch and introduces an important new feature into the spectrum of relic gravity waves created quantum mechanically during inflation. The amplitude of the gravity wave spectrum increases with the wave number for wavelengths shorter than the comoving horizon scale at the commencement of the radiative regime. This 'blue tilt' is a generic feature of models with steep potentials and imposes strong constraints on a class of inflationary braneworld models. Prospects for detection of the gravity wave background by terrestrial and space-borne gravity wave observatories such as LIGO II and LISA are discussed

  11. RNA Relics and Origin of Life

    Directory of Open Access Journals (Sweden)

    Laurent Vial

    2009-07-01

    Full Text Available A number of small RNA sequences, located in different non-coding sequences and highly preserved across the tree of life, have been suggested to be molecular fossils, of ancient (and possibly primordial origin. On the other hand, recent years have revealed the existence of ubiquitous roles for small RNA sequences in modern organisms, in functions ranging from cell regulation to antiviral activity. We propose that a single thread can be followed from the beginning of life in RNA structures selected only for stability reasons through the RNA relics and up to the current coevolution of RNA sequences; such an understanding would shed light both on the history and on the present development of the RNA machinery and interactions. After presenting the evidence (by comparing their sequences that points toward a common thread, we discuss a scenario of genome coevolution (with emphasis on viral infectious processes and finally propose a plan for the reevaluation of the stereochemical theory of the genetic code; we claim that it may still be relevant, and not only for understanding the origin of life, but also for a comprehensive picture of regulation in present-day cells.

  12. RNA Relics and Origin of Life

    Science.gov (United States)

    Demongeot, Jacques; Glade, Nicolas; Moreira, Andrés; Vial, Laurent

    2009-01-01

    A number of small RNA sequences, located in different non-coding sequences and highly preserved across the tree of life, have been suggested to be molecular fossils, of ancient (and possibly primordial) origin. On the other hand, recent years have revealed the existence of ubiquitous roles for small RNA sequences in modern organisms, in functions ranging from cell regulation to antiviral activity. We propose that a single thread can be followed from the beginning of life in RNA structures selected only for stability reasons through the RNA relics and up to the current coevolution of RNA sequences; such an understanding would shed light both on the history and on the present development of the RNA machinery and interactions. After presenting the evidence (by comparing their sequences) that points toward a common thread, we discuss a scenario of genome coevolution (with emphasis on viral infectious processes) and finally propose a plan for the reevaluation of the stereochemical theory of the genetic code; we claim that it may still be relevant, and not only for understanding the origin of life, but also for a comprehensive picture of regulation in present-day cells. PMID:20111682

  13. Boltzmann hierarchy for interacting neutrinos I: formalism

    International Nuclear Information System (INIS)

    Oldengott, Isabel M.; Rampf, Cornelius; Wong, Yvonne Y.Y.

    2015-01-01

    Starting from the collisional Boltzmann equation, we derive for the first time and from first principles the Boltzmann hierarchy for neutrinos including interactions with a scalar particle. Such interactions appear, for example, in majoron-like models of neutrino mass generation. We study two limits of the scalar mass: (i) An extremely massive scalar whose only role is to mediate an effective 4-fermion neutrino-neutrino interaction, and (ii) a massless scalar that can be produced in abundance and thus demands its own Boltzmann hierarchy. In contrast to, e.g., the first-order Boltzmann hierarchy for Thomson-scattering photons, our interacting neutrino/scalar Boltzmann hierarchies contain additional momentum-dependent collision terms arising from a non-negligible energy transfer in the neutrino-neutrino and neutrino-scalar interactions. This necessitates that we track each momentum mode of the phase space distributions individually, even if the particles were massless. Comparing our hierarchy with the commonly used (c eff 2 ,c vis 2 )-parameterisation, we find no formal correspondence between the two approaches, which raises the question of whether the latter parameterisation even has an interpretation in terms of particle scattering. Lastly, although we have invoked majoron-like models as a motivation for our study, our treatment is in fact generally applicable to all scenarios in which the neutrino and/or other ultrarelativistic fermions interact with scalar particles

  14. New light Higgs boson and short-baseline neutrino anomalies

    Science.gov (United States)

    Asaadi, J.; Church, E.; Guenette, R.; Jones, B. J. P.; Szelc, A. M.

    2018-04-01

    The low-energy excesses observed by the MiniBooNE experiment have, to date, defied a convincing explanation under the standard model even with accommodation for nonzero neutrino mass. In this paper we explore a new oscillation mechanism to explain these anomalies, invoking a light neutrinophilic Higgs boson, conceived to induce a low Dirac neutrino mass in accord with experimental limits. Beam neutrinos forward scattering off of a locally overdense relic neutrino background give rise to a novel matter effect with an energy-specific resonance. An enhanced oscillation around this resonance peak produces flavor transitions which are highly consistent with the MiniBooNE neutrino- and antineutrino-mode data sets. The model provides substantially improved χ2 values beyond either the no-oscillation hypothesis or the more commonly explored 3 +1 sterile neutrino hypothesis. This mechanism would introduce distinctive signatures at each baseline in the upcoming short-baseline neutrino program at Fermilab, presenting opportunities for further exploration.

  15. Neutrino mixing and future accelerator neutrino experiments

    International Nuclear Information System (INIS)

    Bilenky, S.M.

    1992-01-01

    No evidence for neutrino mixing has been obtained in experiments searching for oscillations with neutrinos from accelerators and reactors. The possible reason is that neutrino masses are too small to produce any sizable effects in the experiments with terrestrial neutrinos. We put forward here the point of view that the reason for that can be traced to the presence of a hierarchy of neutrino masses as well as strength of couplings between lepton families. (orig.)

  16. Relics in galaxy clusters at high radio frequencies

    Science.gov (United States)

    Kierdorf, M.; Beck, R.; Hoeft, M.; Klein, U.; van Weeren, R. J.; Forman, W. R.; Jones, C.

    2017-04-01

    Aims: We investigated the magnetic properties of radio relics located at the peripheries of galaxy clusters at high radio frequencies, where the emission is expected to be free of Faraday depolarization. The degree of polarization is a measure of the magnetic field compression and, hence, the Mach number. Polarization observations can also be used to confirm relic candidates. Methods: We observed three radio relics in galaxy clusters and one radio relic candidate at 4.85 and 8.35 GHz in total emission and linearly polarized emission with the Effelsberg 100-m telescope. In addition, we observed one radio relic candidate in X-rays with the Chandra telescope. We derived maps of polarization angle, polarization degree, and Faraday rotation measures. Results: The radio spectra of the integrated emission below 8.35 GHz can be well fitted by single power laws for all four relics. The flat spectra (spectral indices of 0.9 and 1.0) for the so-called Sausage relic in cluster CIZA J2242+53 and the so-called Toothbrush relic in cluster 1RXS 06+42 indicate that models describing the origin of relics have to include effects beyond the assumptions of diffuse shock acceleration. The spectra of the radio relics in ZwCl 0008+52 and in Abell 1612 are steep, as expected from weak shocks (Mach number ≈2.4). Polarization observations of radio relics offer a method of measuring the strength and geometry of the shock front. We find polarization degrees of more than 50% in the two prominent Mpc-sized radio relics, the Sausage and the Toothbrush, which are among the highest percentages of linear polarization detected in any extragalactic radio source to date. This is remarkable because the large beam size of the Effelsberg single-dish telescope corresponds to linear extensions of about 300 kpc at 8.35 GHz at the distances of the relics. The high degree of polarization indicates that the magnetic field vectors are almost perfectly aligned along the relic structure, as expected for shock

  17. Neutrino horn

    CERN Multimedia

    1967-01-01

    View of the new neutrino horn installed in its blockhouse from the target end. Protons pass through the 2mm hole in the centre of the small fluorescent screen, hitting the target immediately behind it. The circular tubes carry pressurized cooling water.

  18. Neutrino Oscillations

    Indian Academy of Sciences (India)

    The 2015 Nobel Prize in Physics was awarded to two physicists-Takaaki Kajita and Arthur B McDonald, whose teams discoveredthat neutrinos, which come in three flavours, changefrom one flavour to another. This discovery is a major milestonein particle physics as it gives a clear evidence of physicsbeyond the Standard ...

  19. Solar Neutrinos

    Indian Academy of Sciences (India)

    7,81. The Chlorine experiment, located in the Homestake Gold Mine in Lead, South Dakota, was the first solar neutrino experiment to be set up. A tank of. 105 gallons of perchloroethylene in which the electron neu- trino reacts with chlorine to ...

  20. Dark matter physics in neutrino specific two Higgs doublet model

    Energy Technology Data Exchange (ETDEWEB)

    Baek, Seungwon; Nomura, Takaaki [School of Physics, Korea Institute for Advanced Study,85 Hoegiro, Dongdaemun-gu, Seoul 02455 (Korea, Republic of)

    2017-03-10

    Although the seesaw mechanism is a natural explanation for the small neutrino masses, there are cases when the Majorana mass terms for the right-handed neutrinos are not allowed due to symmetry. In that case, if neutrino-specific Higgs doublet is introduced, neutrinos become Dirac particles and their small masses can be explained by its small VEV. We show that the same symmetry, which we assume a global U(1){sub X}, can also be used to explain the stability of dark matter. In our model, a new singlet scalar breaks the global symmetry spontaneously down to a discrete Z{sub 2} symmetry. The dark matter particle, lightest Z{sub 2}-odd fermion, is stabilized. We discuss the phenomenology of dark matter: relic density, direct detection, and indirect detection. We find that the relic density can be explained by a novel Goldstone boson channel or by resonance channel. In the most region of parameter space considered, the direct detections is suppressed well below the current experimental bound. Our model can be further tested in indirect detection experiments such as FermiLAT gamma ray searches or neutrinoless double beta decay experiments.

  1. Neutrino Interactions

    International Nuclear Information System (INIS)

    Kamyshkov, Yuri; Handler, Thomas

    2016-01-01

    The neutrino group of the University of Tennessee, Knoxville was involved from 05/01/2013 to 04/30/2015 in the neutrino physics research funded by DOE-HEP grant DE-SC0009861. Contributions were made to the Double Chooz nuclear reactor experiment in France where second detector was commissioned during this period and final series of measurements has been started. Although Double Chooz was smaller experimental effort than competitive Daya Bay and RENO experiments, its several advantages make it valuable for understanding of systematic errors in measurements of neutrino oscillations. Double Chooz was the first experiment among competing three that produced initial result for neutrino angle θ_1_3 measurement, giving other experiments the chance to improve measured value statistically. Graduate student Ben Rybolt defended his PhD thesis on the results of Double Chooz experiment in 2015. UT group has fulfilled all the construction and analysis commitments to Double Chooz experiment, and has withdrawn from the collaboration by the end of the mentioned period to start another experiment. Larger effort of UT neutrino group during this period was devoted to the participation in another DOE-HEP project - NOvA experiment. The 14,000-ton 'FAR' neutrino detector was commissioned in northern Minnesota in 2014 together with 300-ton 'NEAR' detector located at Fermilab. Following that, the physics measurement program has started when Fermilab accelerator complex produced the high-intensity neutrino beam propagating through Earth to detector in MInnessota. UT group contributed to NOvA detector construction and developments in several aspects. Our Research Associate Athanasios Hatzikoutelis was managing (Level 3 manager) the construction of the Detector Control System. This work was successfully accomplished in time with the commissioning of the detectors. Group was involved in the development of the on-line software and study of the signatures of the cosmic ray backgrounds

  2. Neutrino Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Kamyshkov, Yuri [Univ. of Tennesse, Knoxville, TN (United States); Handler, Thomas [Univ. of Tennesse, Knoxville, TN (United States)

    2016-10-24

    The neutrino group of the University of Tennessee, Knoxville was involved from 05/01/2013 to 04/30/2015 in the neutrino physics research funded by DOE-HEP grant DE-SC0009861. Contributions were made to the Double Chooz nuclear reactor experiment in France where second detector was commissioned during this period and final series of measurements has been started. Although Double Chooz was smaller experimental effort than competitive Daya Bay and RENO experiments, its several advantages make it valuable for understanding of systematic errors in measurements of neutrino oscillations. Double Chooz was the first experiment among competing three that produced initial result for neutrino angle θ13 measurement, giving other experiments the chance to improve measured value statistically. Graduate student Ben Rybolt defended his PhD thesis on the results of Double Chooz experiment in 2015. UT group has fulfilled all the construction and analysis commitments to Double Chooz experiment, and has withdrawn from the collaboration by the end of the mentioned period to start another experiment. Larger effort of UT neutrino group during this period was devoted to the participation in another DOE-HEP project - NOvA experiment. The 14,000-ton "FAR" neutrino detector was commissioned in northern Minnesota in 2014 together with 300-ton "NEAR" detector located at Fermilab. Following that, the physics measurement program has started when Fermilab accelerator complex produced the high-intensity neutrino beam propagating through Earth to detector in MInnessota. UT group contributed to NOvA detector construction and developments in several aspects. Our Research Associate Athanasios Hatzikoutelis was managing (Level 3 manager) the construction of the Detector Control System. This work was successfully accomplished in time with the commissioning of the detectors. Group was involved in the development of the on-line software and study of the signatures of the cosmic ray backgrounds

  3. Future neutrino experiments

    CERN Document Server

    Di Lella, L

    2001-01-01

    Future experiments to search for neutrino oscillations using neutrinos from the Sun, from reactors and accelerators are reviewed. Possible long-term developments based on neutrino factories are also described. (29 refs).

  4. 1020 eV cosmic-ray and particle physics with kilometer-scale neutrino telescopes

    International Nuclear Information System (INIS)

    Alvarez-Muniz, J.; Halzen, F.

    2001-01-01

    We show that a kilometer-scale neutrino observatory, though optimized for TeV to PeV energy, is sensitive to the neutrinos associated with super-EeV sources. These include super-heavy relics, neutrinos associated with the Greisen cutoff, and topological defects which are remnant cosmic structures associated with phase transitions in grand unified gauge theories. It is a misconception that new instruments optimized to EeV energy are required to do this important science, although this is not their primary goal. Because kilometer-scale neutrino telescopes can reject atmospheric backgrounds by establishing the very high energy of the signal events, they have sensitivity over the full solid angle, including the horizon where most of the signal is concentrated. This is important because up-going neutrino-induced muons, routinely considered in previous calculations, are absorbed by the Earth

  5. Probing Dark Energy via Neutrino and Supernova Observatories

    International Nuclear Information System (INIS)

    Hall, Lawrence; Hall, Lawrence J.; Murayama, Hitoshi; Papucci, Michele; Perez, Gilad

    2006-01-01

    A novel method for extracting cosmological evolution parameters is proposed, using a probe other than light: future observations of the diffuse anti-neutrino flux emitted from core-collapse supernovae (SNe), combined with the SN rate extracted from future SN surveys. The relic SN neutrino differential flux can be extracted by using future neutrino detectors such as Gadolinium-enriched, megaton, water detectors or 100-kiloton detectors of liquid Argon or liquid scintillator. The core-collapse SN rate can be reconstructed from direct observation of SN explosions using future precision observatories. Our method, by itself, cannot compete with the accuracy of the optical-based measurements but may serve as an important consistency check as well as a source of complementary information. The proposal does not require construction of a dedicated experiment, but rather relies on future experiments proposed for other purposes

  6. Probing Dark Energy via Neutrino and Supernova Observatories

    Energy Technology Data Exchange (ETDEWEB)

    Hall, Lawrence; Hall, Lawrence J.; Murayama, Hitoshi; Papucci, Michele; Perez, Gilad

    2006-07-10

    A novel method for extracting cosmological evolution parameters is proposed, using a probe other than light: future observations of the diffuse anti-neutrino flux emitted from core-collapse supernovae (SNe), combined with the SN rate extracted from future SN surveys. The relic SN neutrino differential flux can be extracted by using future neutrino detectors such as Gadolinium-enriched, megaton, water detectors or 100-kiloton detectors of liquid Argon or liquid scintillator. The core-collapse SN rate can be reconstructed from direct observation of SN explosions using future precision observatories. Our method, by itself, cannot compete with the accuracy of the optical-based measurements but may serve as an important consistency check as well as a source of complementary information. The proposal does not require construction of a dedicated experiment, but rather relies on future experiments proposed for other purposes.

  7. Neutrinos: Theory and Phenomenology

    Energy Technology Data Exchange (ETDEWEB)

    Parke, Stephen

    2013-10-22

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

  8. Inhomogeneous neutrino degeneracy and big bang nucleosynthesis

    International Nuclear Information System (INIS)

    Whitmire, Scott E.; Scherrer, Robert J.

    2000-01-01

    We examine big bang nucleosynthesis (BBN) in the case of inhomogeneous neutrino degeneracy, in the limit where the fluctuations are sufficiently small on large length scales that the present-day element abundances are homogeneous. We consider two representative cases: degeneracy of the electron neutrino alone and equal chemical potentials for all three neutrinos. We use a linear programming method to constrain an arbitrary distribution of the chemical potentials. For the current set of (highly restrictive) limits on the primordial element abundances, homogeneous neutrino degeneracy barely changes the allowed range of the baryon-to-photon ratio η. Inhomogeneous degeneracy allows for little change in the lower bound on η, but the upper bound in this case can be as large as η=1.1x10 -8 (only ν e degeneracy) or η=1.0x10 -9 (equal degeneracies for all three neutrinos). For the case of inhomogeneous neutrino degeneracy, we show that there is no BBN upper bound on the neutrino energy density, which is bounded in this case only by limits from structure formation and the cosmic microwave background. (c) 2000 The American Physical Society

  9. Supernova neutrinos

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    In the first part of his in-depth article on the 1987 supernova, David Schramm of the University of Chicago and the NASA/Fermilab Astrophysics Centre reviewed the background to supernovae, the composition of massive stars and the optical history of SN 1987A, and speculated on what the 1987 remnant might be. In such a Type II supernova, gravitational pressure crushes the atoms of the star's interior producing neutron matter, or even a black hole, and releasing an intense burst of neutrinos. 1987 was the first time that physicists were equipped (but not entirely ready!) to intercept these particles, and in the second part of his article, David Schramm covers the remarkable new insights from the science of supernova neutrino astronomy, born on 23 February 1987

  10. The Intermediate Neutrino Program

    CERN Document Server

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

    2015-01-01

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

  11. The Intermediate Neutrino Program

    Energy Technology Data Exchange (ETDEWEB)

    Adams, C.; et al.

    2015-03-23

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

  12. The Intermediate Neutrino Program

    Energy Technology Data Exchange (ETDEWEB)

    Adams, C. [Yale Univ., New Haven, CT (United States); Alonso, J. R. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Ankowski, A. M. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Asaadi, J. A. [Syracuse Univ., NY (United States); Ashenfelter, J. [Yale Univ., New Haven, CT (United States); Axani, S. N. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Babu, K [Oklahoma State Univ., Stillwater, OK (United States); Backhouse, C. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Band, H. R. [Yale Univ., New Haven, CT (United States); Barbeau, P. S. [Duke Univ., Durham, NC (United States); Barros, N. [Univ. of Pennsylvania, Philadelphia, PA (United States); Bernstein, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Betancourt, M. [Illinois Inst. of Technology, Chicago, IL (United States); Bishai, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Blucher, E. [Univ. of Chicago, IL (United States); Bouffard, J. [State Univ. of New York (SUNY), Albany, NY (United States); Bowden, N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Brice, S. [Illinois Inst. of Technology, Chicago, IL (United States); Bryan, C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Camilleri, L. [Columbia Univ., New York, NY (United States); Cao, J. [Inst. of High Energy Physics, Beijing (China); Carlson, J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Carr, R. E. [Columbia Univ., New York, NY (United States); Chatterjee, A. [Univ. of Texas, Arlington, TX (United States); Chen, M. [Univ. of California, Irvine, CA (United States); Chen, S. [Tsinghua Univ., Beijing (China); Chiu, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Church, E. D. [Illinois Inst. of Technology, Chicago, IL (United States); Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Collar, J. I. [Univ. of Chicago, IL (United States); Collin, G. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Conrad, J. M. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Convery, M. R. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Cooper, R. L. [Indiana Univ., Bloomington, IN (United States); Cowen, D. [Pennsylvania State Univ., University Park, PA (United States); Davoudiasl, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Gouvea, A. D. [Northwestern Univ., Evanston, IL (United States); Dean, D. J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Deichert, G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Descamps, F. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); DeYoung, T. [Michigan State Univ., East Lansing, MI (United States); Diwan, M. V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Djurcic, Z. [Argonne National Lab. (ANL), Argonne, IL (United States); Dolinski, M. J. [Drexel Univ., Philadelphia, PA (United States); Dolph, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Donnelly, B. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Dwyer, D. A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Dytman, S. [Univ. of Pittsburgh, PA (United States); Efremenko, Y. [Univ. of Tennessee, Knoxville, TN (United States); Everett, L. L. [Univ. of Wisconsin, Madison, WI (United States); Fava, A. [University of Padua, Padova (Italy); Figueroa-Feliciano, E. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Fleming, B. [Yale Univ., New Haven, CT (United States); Friedland, A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Fujikawa, B. K. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Gaisser, T. K. [Univ. of Delaware, Newark, DE (United States); Galeazzi, M. [Univ. of Miami, FL (United States); Galehouse, DC [Univ. of Akron, OH (United States); Galindo-Uribarri, A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Garvey, G. T. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gautam, S. [Tribhuvan Univ., Kirtipur (Nepal); Gilje, K. E. [Illinois Inst. of Technology, Chicago, IL (United States); Gonzalez-Garcia, M. [Stony Brook Univ., NY (United States); Goodman, M. C. [Argonne National Lab. (ANL), Argonne, IL (United States); Gordon, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Gramellini, E. [Yale Univ., New Haven, CT (United States); Green, M. P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Guglielmi, A. [University of Padua, Padova (Italy); Hackenburg, R. W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hackenburg, A. [Yale Univ., New Haven, CT (United States); Halzen, F. [Univ. of Wisconsin, Madison, WI (United States); Han, K. [Yale Univ., New Haven, CT (United States); Hans, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Harris, D. [Illinois Inst. of Technology, Chicago, IL (United States); Heeger, K. M. [Yale Univ., New Haven, CT (United States); Herman, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hill, R. [Univ. of Chicago, IL (United States); Holin, A. [Univ. College London, Bloomsbury (United Kingdom); Huber, P. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Jaffe, D. E. [Brookhaven National Lab. (BNL), Upton, NY (United States); Johnson, R. A. [Univ. of Cincinnati, OH (United States); Joshi, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Karagiorgi, G. [Univ. of Manchester (United Kingdom); Kaufman, L. J. [Indiana Univ., Bloomington, IN (United States); Kayser, B. [Illinois Inst. of Technology, Chicago, IL (United States); Kettell, S. H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Kirby, B. J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Klein, J. R. [Univ. of Texas, Arlington, TX (United States); Kolomensky, Y. G. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Kriske, R. M. [Univ. of Minnesota, Minneapolis, MN (United States); Lane, C. E. [Drexel Univ., Philadelphia, PA (United States); Langford, T. J. [Yale Univ., New Haven, CT (United States); Lankford, A. [Univ. of California, Irvine, CA (United States); Lau, K. [Univ. of Houston, TX (United States); Learned, J. G. [Univ. of Hawaii, Honolulu, HI (United States); Ling, J. [Univ. of Illinois, Urbana-Champaign, IL (United States); Link, J. M. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Lissauer, D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Littenberg, L. [Brookhaven National Lab. (BNL), Upton, NY (United States); Littlejohn, B. R. [Illinois Inst. of Technology, Chicago, IL (United States); Lockwitz, S. [Illinois Inst. of Technology, Chicago, IL (United States); Lokajicek, M. [Inst. of Physics of the Academy of Sciences of Czech Republic, Prague (Czech Republic); Louis, W. C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Luk, K. [Univ. of California, Berkeley, CA (United States); Lykken, J. [Illinois Inst. of Technology, Chicago, IL (United States); Marciano, W. J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Maricic, J. [Univ. of Hawaii, Honolulu, HI (United States); Markoff, D. M. [North Carolina Central Univ., Durham, NC (United States); Caicedo, D. A. M. [Illinois Inst. of Technology, Chicago, IL (United States); Mauger, C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mavrokoridis, K. [Univ. of Liverpool (United Kingdom); McCluskey, E. [Illinois Inst. of Technology, Chicago, IL (United States); McKeen, D. [Univ. of Washington, Seattle, WA (United States); McKeown, R. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Mills, G. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mocioiu, I. [Pennsylvania State Univ., University Park, PA (United States); Monreal, B. [Univ. of California, Santa Barbara, CA (United States); Mooney, M. R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Morfin, J. G. [Illinois Inst. of Technology, Chicago, IL (United States); Mumm, P. [National Inst. of Standards and Technology (NIST), Boulder, CO (United States); Napolitano, J. [Temple Univ., Philadelphia, PA (United States); Neilson, R. [Drexel Univ., Philadelphia, PA (United States); Nelson, J. K. [College of William and Mary, Williamsburg, VA (United States); Nessi, M. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Norcini, D. [Yale Univ., New Haven, CT (United States); Nova, F. [Univ. of Texas, Austin, TX (United States); Nygren, D. R. [Univ. of Texas, Arlington, TX (United States); Gann, GDO [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Palamara, O. [Illinois Inst. of Technology, Chicago, IL (United States); Parsa, Z. [Brookhaven National Lab. (BNL), Upton, NY (United States); Patterson, R. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Paul, P. [Stony Brook Univ., NY (United States); Pocar, A. [Univ. of Massachusetts, Amherst, MA (United States); Qian, X. [Brookhaven National Lab. (BNL), Upton, NY (United States); Raaf, J. L. [Illinois Inst. of Technology, Chicago, IL (United States); Rameika, R. [Illinois Inst. of Technology, Chicago, IL (United States); Ranucci, G. [National Inst. of Nuclear Physics, Milano (Italy); Ray, H. [Univ. of Florida, Gainesville, FL (United States); Reyna, D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Rich, G. C. [Triangle Universities Nuclear Lab., Durham, NC (United States); Rodrigues, P. [Univ. of Rochester, NY (United States); Romero, E. R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States); Rosero, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Rountree, S. D. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Rybolt, B. [Univ. of Tennessee, Knoxville, TN (United States); Sanchez, M. C. [Iowa State Univ., Ames, IA (United States); Santucci, G. [Stony Brook Univ., NY (United States); Schmitz, D. [Univ. of Chicago, IL (United States); Scholberg, K. [Duke Univ., Durham, NC (United States); Seckel, D. [Univ. of Delaware, Newark, DE (United States); Shaevitz, M. [Columbia Univ., New York, NY (United States); Shrock, R. [Stony Brook Univ., NY (United States); Smy, M. B. [Univ. of California, Irvine, CA (United States); Soderberg, M. [Syracuse Univ., NY (United States); Sonzogni, A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Sousa, A. B. [Univ. of Cincinnati, OH (United States); Spitz, J. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); John, J. M. S. [Univ. of Cincinnati, OH (United States); Stewart, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Strait, J. B. [Illinois Inst. of Technology, Chicago, IL (United States); Sullivan, G. [Univ. of Maryland, College Park, MD (United States); Svoboda, R. [Univ. of California, Davis, CA (United States); Szelc, A. M. [Yale Univ., New Haven, CT (United States); Tayloe, R. [Indiana Univ., Bloomington, IN (United States); Thomson, M. A. [Univ. of Cambridge (United Kingdom); Toups, M. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Vacheret, A. [Univ. of Oxford (United Kingdom); Vagins, M. [Univ. of California, Irvine, CA (United States); Water, R. G. V. D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Vogelaar, R. B. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Weber, M. [Bern (Switzerland); Weng, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Wetstein, M. [Univ. of Chicago, IL (United States); White, C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); White, B. R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Whitehead, L. [Univ. of Houston, TX (United States); Whittington, D. W. [Indiana Univ., Bloomington, IN (United States); Wilking, M. J. [Stony Brook Univ., NY (United States); Wilson, R. J. [Colorado State Univ., Fort Collins, CO (United States); Wilson, P. [Illinois Inst. of Technology, Chicago, IL (United States); Winklehner, D. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Winn, D. R. [Fairfield Univ., CT (United States); Worcester, E. [Brookhaven National Lab. (BNL), Upton, NY (United States); Yang, L. [Univ. of Illinois, Urbana-Champaign, IL (United States); Yeh, M [Brookhaven National Lab. (BNL), Upton, NY (United States); Yokley, Z. W. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Yoo, J. [Illinois Inst. of Technology, Chicago, IL (United States); Yu, B. [Brookhaven National Lab. (BNL), Upton, NY (United States); Yu, J. [Univ. of Texas, Arlington, TX (United States); Zhang, C. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2017-04-03

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

  13. Neutrino problems proliferate (Neutrino 94 conference report)

    International Nuclear Information System (INIS)

    Gordon, Fraser

    1994-01-01

    The enigma of the neutrino continues. More than sixty years after its hesitant prediction by Pauli and forty years after its discovery by Reines and Cowan, the neutrino still refuses to give up all its secrets. The longer we travel down the neutrino road and the more we find out about these particles, the more problems we uncover en route. The present state of the neutrino mystery was highlighted at the Neutrino 94 meeting in Eilat, Israel, from 29 May to 3 June. It was a distinguished meeting, with the first morning including one session chaired by neutrino co-discoverer Fred Reines, and an introductory talk by muon-neutrino co-discoverer Leon Lederman. One figurehead neutrino personality conspicuously absent this time was Bruno Pontecorvo, who died last year and had attended the previous conference in the series, in Grenada, Spain, in 1992

  14. Neutrino problems proliferate (Neutrino 94 conference report)

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, Fraser

    1994-09-15

    The enigma of the neutrino continues. More than sixty years after its hesitant prediction by Pauli and forty years after its discovery by Reines and Cowan, the neutrino still refuses to give up all its secrets. The longer we travel down the neutrino road and the more we find out about these particles, the more problems we uncover en route. The present state of the neutrino mystery was highlighted at the Neutrino 94 meeting in Eilat, Israel, from 29 May to 3 June. It was a distinguished meeting, with the first morning including one session chaired by neutrino co-discoverer Fred Reines, and an introductory talk by muon-neutrino co-discoverer Leon Lederman. One figurehead neutrino personality conspicuously absent this time was Bruno Pontecorvo, who died last year and had attended the previous conference in the series, in Grenada, Spain, in 1992.

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

    International Nuclear Information System (INIS)

    Foot, R.; Volkas, R.R.

    1997-01-01

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

  16. Thermal relic dark matter beyond the unitarity limit

    Energy Technology Data Exchange (ETDEWEB)

    Harigaya, Keisuke [Berkeley Center for Theoretical Physics, Department of Physics, University of California,Berkeley, CA 94720 (United States); Theoretical Physics Group, Lawrence Berkeley National Laboratory,Berkeley, CA 94720 (United States); Ibe, Masahiro [Kavli IPMU (WPI), UTIAS, The University of Tokyo,Kashiwa, Chiba 277-8583 (Japan); ICRR, The University of Tokyo,Kashiwa, Chiba 277-8582 (Japan); Kaneta, Kunio [Center for Theoretical Physics of the Universe, Institute for Basic Science (IBS),Daejeon 34051 (Korea, Republic of); Nakano, Wakutaka; Suzuki, Motoo [Kavli IPMU (WPI), UTIAS, The University of Tokyo,Kashiwa, Chiba 277-8583 (Japan); ICRR, The University of Tokyo,Kashiwa, Chiba 277-8582 (Japan)

    2016-08-25

    We discuss a simple model of thermal relic dark matter whose mass can be much larger than the so-called unitarity limit on the mass of point-like particle dark matter. The model consists of new strong dynamics with one flavor of fermions in the fundamental representation which is much heavier than the dynamical scale of the new strong dynamics. Dark matter is identified with the lightest baryonic hadron of the new dynamics. The baryonic hadrons annihilate into the mesonic hadrons of the new strong dynamics when they have large radii. Resultantly, thermal relic dark matter with a mass in the PeV range is possible.

  17. Neutrino 2004: Collection of Presentations

    International Nuclear Information System (INIS)

    2004-01-01

    The scientific program covers the latest developments in neutrino physics, astrophysics and related topics through a set of invited talks and 2 poster sessions. The following issues are addressed: - solar neutrinos, - atmospheric neutrinos, - short and long baseline experiments, - neutrino oscillations, - double beta decay, - direct neutrino mass limits, - theory for neutrino masses, neutrino telescopes and ultra-high energy neutrinos, - dark matter searches, - neutrino in astrophysics and cosmology, and - future projects beams and experiments

  18. Neutrino 2004: Collection of Presentations

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    The scientific program covers the latest developments in neutrino physics, astrophysics and related topics through a set of invited talks and 2 poster sessions. The following issues are addressed: - solar neutrinos, - atmospheric neutrinos, - short and long baseline experiments, - neutrino oscillations, - double beta decay, - direct neutrino mass limits, - theory for neutrino masses, neutrino telescopes and ultra-high energy neutrinos, - dark matter searches, - neutrino in astrophysics and cosmology, and - future projects beams and experiments.

  19. ABSOLUTE NEUTRINO MASSES

    DEFF Research Database (Denmark)

    Schechter, J.; Shahid, M. N.

    2012-01-01

    We discuss the possibility of using experiments timing the propagation of neutrino beams over large distances to help determine the absolute masses of the three neutrinos.......We discuss the possibility of using experiments timing the propagation of neutrino beams over large distances to help determine the absolute masses of the three neutrinos....

  20. Working Group Report: Neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    de Gouvea, A.; Pitts, K.; Scholberg, K.; Zeller, G. P. [et al.

    2013-10-16

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

  1. Underground neutrino astronomy

    International Nuclear Information System (INIS)

    Schramm, D.N.

    1983-02-01

    A review is made of possible astronomical neutrino sources detectable with underground facilities. Comments are made about solar neutrinos and gravitational-collapse neutrinos, and particular emphasis is placed on ultra-high-energy astronomical neutrino sources. An appendix mentions the exotic possibility of monopolonium

  2. Introduction to massive neutrinos

    International Nuclear Information System (INIS)

    Kayser, B.

    1984-01-01

    We discuss the theoretical ideas which make it natural to expect that neutrinos do indeed have mass. Then we focus on the physical consequences of neutrino mass, including neutrino oscillation and other phenomena whose observation would be very interesting, and would serve to demonstrate that neutrinos are indeed massive. We comment on the legitimacy of comparing results from different types of experiments. Finally, we consider the question of whether neutrinos are their own antiparticles. We explain what this question means, discuss the nature of a neutrino which is its own antiparticles, and consider how one might determine experimentally whether neutrinos are their own antiparticles or not

  3. Neutrinos in Nuclear Physics

    Energy Technology Data Exchange (ETDEWEB)

    McKeown, Bob [bmck@jlab.org

    2015-06-01

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

  4. APPLICATION OF 3D MODEL OF CULTURAL RELICS IN VIRTUAL RESTORATION

    Directory of Open Access Journals (Sweden)

    S. Zhao

    2018-04-01

    Full Text Available In the traditional cultural relics splicing process, in order to identify the correct spatial location of the cultural relics debris, experts need to manually splice the existing debris. The repeated contact between debris can easily cause secondary damage to the cultural relics. In this paper, the application process of 3D model of cultural relic in virtual restoration is put forward, and the relevant processes and ideas are verified with the example of Terracotta Warriors data. Through the combination of traditional cultural relics restoration methods and computer virtual reality technology, virtual restoration of high-precision 3D models of cultural relics can provide a scientific reference for virtual restoration, avoiding the secondary damage to the cultural relics caused by improper restoration. The efficiency and safety of the preservation and restoration of cultural relics have been improved.

  5. Application of 3d Model of Cultural Relics in Virtual Restoration

    Science.gov (United States)

    Zhao, S.; Hou, M.; Hu, Y.; Zhao, Q.

    2018-04-01

    In the traditional cultural relics splicing process, in order to identify the correct spatial location of the cultural relics debris, experts need to manually splice the existing debris. The repeated contact between debris can easily cause secondary damage to the cultural relics. In this paper, the application process of 3D model of cultural relic in virtual restoration is put forward, and the relevant processes and ideas are verified with the example of Terracotta Warriors data. Through the combination of traditional cultural relics restoration methods and computer virtual reality technology, virtual restoration of high-precision 3D models of cultural relics can provide a scientific reference for virtual restoration, avoiding the secondary damage to the cultural relics caused by improper restoration. The efficiency and safety of the preservation and restoration of cultural relics have been improved.

  6. Neutrinos and Einstein

    CERN Document Server

    Suzuki, Yoichiro

    2005-01-01

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

  7. 50 years of neutrinos

    CERN Document Server

    Goldhaber, M

    1980-01-01

    On December 4 1930, Wolfgang Pauli addressed an "open letter" to Lise Meitner and others attending a physics meeting, suggesting the neutrino as a way out of the difficulties confronted in beta rays research, especially by the existence of a continuous beta spectrum. He proposed a new particle later called the neutrino. The prehistory leading up to Pauli's letter will be reviewed, as well as the later discovery of the electron-neutrino followed by the muon-neutrino. There are now believed to be three different types of neutrino and their anti-particles. Neutrinos have a spin 1/2; but only one spin component has been found in nature: neutrinos go forward as "left-handed" screws and anti-neutrinos as "right-handed" ones. A question still not convincingly resolved today is wether neutrinos have a mass different from zero and, if they do, what consequences this would have for the behaviour of neutrinos and for cosmology.

  8. The solar neutrinos epopee

    CERN Document Server

    Lasserre, T

    2003-01-01

    The 2002 year has been fruitful for the neutrino physics. First, the Sudbury Neutrino Observatory (SNO) experiment has shown that the electron neutrinos nu sub e emitted by the sun are converted into muon neutrinos (nu submu) and tau neutrinos (nu subtau), thus closing the 30 years old problem of solar neutrinos deficit. This discovery validates the model of nuclear energy production inside the sun but it shakes the theory describing the weak interactions between the fundamental constituents of matter. This theory considers the neutrinos (and the photons) as massless particles, while the taste conversion phenomenon necessarily implies that neutrinos have a mass. In October 2000, the Universe exploration by the cosmic neutrinos is jointly recognized by R. Davis (USA) and M. Koshiba (Japan) who received the Nobel price of physics. Finally, in December 2000, the KamLAND experiment quantitatively demonstrated the neutrinos metamorphosis by detecting a deficit in the flux of electron antineutrinos coming from the ...

  9. Mixed Inert scalar triplet dark matter, radiative neutrino masses and leptogenesis

    Directory of Open Access Journals (Sweden)

    Wen-Bin Lu

    2017-11-01

    Full Text Available The neutral component of an inert scalar multiplet with hypercharge can provide a stable dark matter particle when its real and imaginary parts have a splitting mass spectrum. Otherwise, a tree-level dark-matter-nucleon scattering mediated by the Z boson will be much above the experimental limit. In this paper we focus on a mixed inert scalar triplet dark matter scenario where a complex scalar triplet with hypercharge can mix with another real scalar triplet without hypercharge through their renormalizable coupling to the standard model Higgs doublet. We consider three specified cases that carry most of the relevant features of the full parameter space: (i the neutral component of the real triplet dominates the dark matter particle, (ii the neutral component of the complex triplet dominates the dark matter particle; and (iii the neutral components of the real and complex triplets equally constitute the dark matter particle. Subject to the dark matter relic abundance and direct detection constraint, we perform a systematic study on the allowed parameter space with particular emphasis on the interplay among triplet-doublet terms and gauge interactions. In the presence of these mixed inert scalar triplets, some heavy Dirac fermions composed of inert fermion doublets can be utilized to generate a tiny Majorana neutrino mass term at one-loop level and realize a successful leptogenesis for explaining the cosmic baryon asymmetry.

  10. Round table discussion of future Solar Neutrino Program

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    The discussion of the future neutrino program includes a critique of the chlorine-37 experiment and the necessary continued effort, the astronomical and cosmological implications of the various nonstandard models, future programs in laboratory experiments and theoretical calculations on reaction cross sections, opacities, convections, and observations of elemental abundances on the Sun and the meteorites, and lastly the program in solar neutrino research

  11. Neutrino physics in heaven

    International Nuclear Information System (INIS)

    Raffelt, G.

    2005-01-01

    After a brief overview of the usual topics that connect astrophysics and cosmology with neutrino physics I will focus on two main themes. First, what can we learn from the neutrino signal of a future galactic supernova, in particular about the neutrino mass ordering. Second, what can we learn about neutrino properties from cosmological observables, notably about the neutrino absolute mass scale from cosmological large-scale structure observables. (author)

  12. Two lectures on neutrinos

    International Nuclear Information System (INIS)

    Ramond, P.

    1992-01-01

    These notes are based on two lectures delivered at the School. A general description of neutrinos is presented, first in purely kinematic terms, then in the context of the Standard Model, focusing on the role of the global lepton numbers. Standard Model extensions with massive neutrinos are cataloged. Several popular mass matrices for neutrinos, and their consequences are presented. They proceed to give an extended discussion of neutrino oscillations in matter, and apply the results to the solar neutrinos

  13. Workshop: Neutrino telescopes

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    Despite being the most elusive of the known particles, neutrinos provide vital new physics insights. Most neutrino knowledge so far has come from studies using beams from reactors and accelerators, but in recent years important new contributions have resulted from investigation of natural neutrinos from cosmic rays, nearby stars (the sun), or distant sources, such as the 1987 supernova. The supernova observations marked the start of a new era in neutrino astronomy, but neutrino telescopes were anyway assured of an important ongoing role

  14. Workshop: Neutrino telescopes

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1990-05-15

    Despite being the most elusive of the known particles, neutrinos provide vital new physics insights. Most neutrino knowledge so far has come from studies using beams from reactors and accelerators, but in recent years important new contributions have resulted from investigation of natural neutrinos from cosmic rays, nearby stars (the sun), or distant sources, such as the 1987 supernova. The supernova observations marked the start of a new era in neutrino astronomy, but neutrino telescopes were anyway assured of an important ongoing role.

  15. Collective neutrino oscillations and neutrino wave packets

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-09-01

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

  16. Radiative corrections for the direct detection of neutralino dark matter and its relic density

    Energy Technology Data Exchange (ETDEWEB)

    Steppeler, Patrick Norbert

    2016-07-01

    entering the Boltzmann equation in many scenarios of the MSSM. The Boltzmann equation allows to determine the neutralino relic density, i.e. to predict their present abundance. This prediction can be checked experimentally and is thus of great phenomenological relevance. Measurements of the temperature fluctuations of the cosmic microwave background permit to determine the relic density precisely. Comparing the theoretical prediction with the experimental finding allows to exclude large fractions of the MSSM parameter space. In order to maximally benefit from the experimental precision, it is necessary to minimise theoretical uncertainties and to include the aforementioned radiative corrections. The radiative corrections to the elastic neutralino-nucleon scattering and the corresponding relic density have been implemented into the numerical package Dark matter at next-to-leading order. With the help of this program, we perform a phenomenological investigation and analyse the impact of the radiative corrections. It turns out that the neutralino relic density depends not on a single but a multitude of gaugino (co)annihilation processes in parallel quite often. The calculated radiative corrections lead to a relative shift of the relic density of up to 10%, which is significantly larger than the experimental uncertainty (±2% at the 1σ confidence level) and demonstrates that these corrections should be included when identifying the cosmologically preferred region of the MSSM. Moreover, we investigate the relation between the relic density and the neutralino-nucleon cross sections. In the spin-independent case, the inclusion of radiative corrections leads to a relative shift roughly +14% in comparison to a tree-level calculation. This shift is comparable to typical recent nuclear uncertainties, which influence the prediction as well. The spin-dependent cross section is subject to even larger shifts and modified by up to -50% by radiative corrections.

  17. Quantum state correction of relic gravitons from quantum gravity

    OpenAIRE

    Rosales, Jose-Luis

    1996-01-01

    The semiclassical approach to quantum gravity would yield the Schroedinger formalism for the wave function of metric perturbations or gravitons plus quantum gravity correcting terms in pure gravity; thus, in the inflationary scenario, we should expect correcting effects to the relic graviton (Zel'dovich) spectrum of the order (H/mPl)^2.

  18. Radiological data acquisition, investigation and evaluation of mining relics

    International Nuclear Information System (INIS)

    1992-01-01

    Within the scope of a Federal Project, the environmental radioactivity and the radon concentration in buildings caused by mining relics in the new Federal Lands of Germany are investigated. In the first phase of the project, about 8000 relics of former mining were identified by analysing existing documents, categorised, and recorded in a special data bank. Thereby, 'areas of suspicion' of 1500 km 2 spaciously defined in the beginning could be reduced to 'areas of investigation' of 250 km 2 now to be examined in close coordination with the land and district authorities by a programme gradually adapted to the radiological significance of the relics. Experience with site-specific measuring programmes have already been gained through three pilot projects at typical sites of former mining activities. Recommendations of the German Radiation Protection Commission serve for the evaluation of the results. By the measuring programme for radon in buildings of mining and geological predestined regions more than 25000 buildings of 210 communities have been investigated. The results confirm the expected prevailing influence of the geologic underground on the radon concentration. Extreme values are observed where direct connections additionally exist to mining relics in the ground. (orig./HP) With 11 figs. in annex [de

  19. Late Quaternary sea level and environmental changes from relic ...

    Indian Academy of Sciences (India)

    Relic carbonate deposits along the western margin of India occur as dolomite crusts, aragonite sands (pelletal / oolitic) and aragonite-cemented limestones, oyster shells, corals, encrusted coralline algal and foraminiferal-dominated nodules. The petrology and mineralogy of the deposits indicate that except for aragonite ...

  20. Dusty Relic to Shining Treasure: Embedded in a Multicultural Environment

    Science.gov (United States)

    Avery, Beth Fuseler; Batman, Cindy

    2014-01-01

    Far from being dusty old relics who are guardians of the book, embedded librarians need to be proactively leading students through the digital maze of the virtual library. Working with students more than 7,000 miles away changed perceptions of how to teach and learn, and how people interact online. We will share how as embedded librarians we…

  1. Cold dark matter plus not-so-clumpy dark relics

    NARCIS (Netherlands)

    Diamanti, R.; Ando, S.; Gariazzo, S.; Mena, O.; Weniger, C.

    Various particle physics models suggest that, besides the (nearly) cold dark matter that accounts for current observations, additional but sub-dominant dark relics might exist. These could be warm, hot, or even contribute as dark radiation. We present here a comprehensive study of two-component dark

  2. Proto-ribosome: a theoretical approach based on RNA relics

    OpenAIRE

    Demongeot, Jacques

    2017-01-01

    We describe in this paper, based on already published articles, a contribution to the theory postulating the existence of a proto-ribosome, which could have appeared early at the origin of life and we discuss the interest of this notion in an evolutionary perspective, taking into account the existence of possible RNA relics of this proto-ribosome.

  3. Relic gravitational waves and the generalized second law

    International Nuclear Information System (INIS)

    Izquierdo, German; Pavon, Diego

    2004-01-01

    The generalized second law of gravitational thermodynamics is applied to the present era of accelerated expansion of the Universe. In spite of the fact that the entropy of matter and relic gravitational waves inside the event horizon diminish, the mentioned law is fulfilled provided that the expression for the entropy density of the gravitational waves satisfies a certain condition

  4. Solar Neutrinos

    Directory of Open Access Journals (Sweden)

    V. Antonelli

    2013-01-01

    relevant indications on the fundamental interactions among particles. After reviewing the striking results of the last two decades, which were determinant to solve the long standing solar neutrino puzzle and refine the Standard Solar Model, we focus our attention on the more recent results in this field and on the experiments presently running or planned for the near future. The main focus at the moment is to improve the knowledge of the mass and mixing pattern and especially to study in detail the lowest energy part of the spectrum, which represents most of the solar neutrino spectrum but is still a partially unexplored realm. We discuss this research project and the way in which present and future experiments could contribute to make the theoretical framework more complete and stable, understanding the origin of some “anomalies” that seem to emerge from the data and contributing to answer some present questions, like the exact mechanism of the vacuum to matter transition and the solution of the so-called solar metallicity problem.

  5. A Zoo of Radio Relics: Cluster Cores to Filaments Ruta Kale1,2 ...

    Indian Academy of Sciences (India)

    Abstract. Radio relics in galaxy clusters can be electrons accelerated at cluster merger shocks or adiabatically compressed fossil radio cocoons or dying radio galaxies. The spectral evolution of radio relics is affected by the surrounding thermal plasma. We present a low frequency study of three radio relics representing ...

  6. Imprints of relic gravitational waves in cosmic microwave background radiation

    International Nuclear Information System (INIS)

    Baskaran, D.; Grishchuk, L. P.; Polnarev, A. G.

    2006-01-01

    A strong variable gravitational field of the very early Universe inevitably generates relic gravitational waves by amplifying their zero-point quantum oscillations. We begin our discussion by contrasting the concepts of relic gravitational waves and inflationary 'tensor modes'. We explain and summarize the properties of relic gravitational waves that are needed to derive their effects on cosmic microwave background (CMB) temperature and polarization anisotropies. The radiation field is characterized by four invariants I, V, E, B. We reduce the radiative transfer equations to a single integral equation of Voltairre type and solve it analytically and numerically. We formulate the correlation functions C l XX ' for X, X ' =T, E, B and derive their amplitudes, shapes and oscillatory features. Although all of our main conclusions are supported by exact numerical calculations, we obtain them, in effect, analytically by developing and using accurate approximations. We show that the TE correlation at lower l's must be negative (i.e. an anticorrelation), if it is caused by gravitational waves, and positive if it is caused by density perturbations. This difference in TE correlation may be a signature more valuable observationally than the lack or presence of the BB correlation, since the TE signal is about 100 times stronger than the expected BB signal. We discuss the detection by WMAP of the TE anticorrelation at l≅30 and show that such an anticorrelation is possible only in the presence of a significant amount of relic gravitational waves (within the framework of all other common assumptions). We propose models containing considerable amounts of relic gravitational waves that are consistent with the measured TT, TE and EE correlations

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

    International Nuclear Information System (INIS)

    Acero-Ortega, Mario Andres

    2009-01-01

    data showed a very low compatibility, so we did not use the I.L.L. data for additional analyses. Our fit of the S.R.S. experiment gave very small values of the goodness-of-fit, indicating that the data are incompatible with the oscillations hypothesis, as well as with the no oscillations hypothesis. We do not have any explanation for this result. From the analysis of the Gosgen experiment, we obtained upper limits for the mixing parameters, excluding the region with sin 2 2θ ≥ 0.3 and Δm ≥ 0.05 eV 2 at 3σ C.L.. With the combination of these data with those of Gallium, Bugey and Chooz, we found that the hint of neutrino oscillations persists with 0.03 ≤ sin 2 2θ ≤ 0.07 and Δm 2 ≅ 1.93 eV 2 , with a good compatibility of the data. However, the no oscillations hypothesis cannot be excluded. Motivated by these results, in the second part of this work we studied cosmological constrains on a light non-thermal sterile neutrino. We fitted up-to-date cosmological data with an extended LCDM model, including light relics with a mass in the range 0.1-10 eV. We obtained constrains on the current density and velocity dispersion of those relics, as well as constrains on their mass, assuming that they consist either of early decoupled thermal relics, or of non-resonantly produced sterile neutrinos. Our results are useful to constrain particle-motivated models with three active neutrinos and one extra light species. We got, for instance, that at the 3σ confidence level, a sterile neutrino with mass m s = 2 eV can be accommodated with the data provided that it is thermally distributed with T s /T id ν ≤ 0.8 (with T id ν the temperature of neutrinos in the instantaneous decoupling limit), or is non-resonantly produced with ΔN eff ≤ 0.5. The bounds become dramatically tighter when the mass increases. For m s ≤ 0.9 eV and at the same confidence level, the data is still compatible with a standard thermalized neutrino. (author)

  8. The physics of neutrinos

    CERN Document Server

    Barger, Vernon D; Whisnant, Kerry

    2012-01-01

    The physics of neutrinos- uncharged elementary particles that are key to helping us better understand the nature of our universe - is one of the most exciting frontiers of modern science. This book provides a comprehensive overview of neutrino physics today and explores promising new avenues of inquiry that could lead to future breakthroughs. The Physics of Neutrinos begins with a concise history of the field and a tutorial on the fundamental properties of neutrinos, and goes on to discuss how the three neutrino types interchange identities as they propagate from their sources to detectors. The book shows how studies of neutrinos produced by such phenomena as cosmic rays in the atmosphere and nuclear reactions in the solar interior provide striking evidence that neutrinos have mass, and it traces our astounding progress in deciphering the baffling experimental findings involving neutrinos. The discovery of neutrino mass offers the first indication of a new kind of physics that goes beyond the Standard Model ...

  9. Neutrino GDR meeting

    International Nuclear Information System (INIS)

    Aguilar-Saavedra, J.A.; Camilleri, L.; Mention, G.; VanElewyck, V.; Verderi, M.; Blondel, A.; Augier, C.; Bellefon, A. de; Coc, A.; Duchesneau, D.; Favier, J.; Lesgourgues, J.; Payet, J.

    2006-01-01

    The purpose of the neutrino GDR (research program coordination) is to federate the activities of French research teams devoted to studying the neutrino. The presentations have been organized on 2 days. A review of the present status of the theoretical and experimental knowledge on neutrinos on a worldwide basis has been made on the first day while the second day has been dedicated to reporting the activities of the 5 following working groups: 1) determination of neutrino parameters, 2) physics beyond the standard model, 3) neutrinos in the universe, 4) neutrino detection, and 5) common tools. During the first day the American neutrino research program has been presented through the description of the 2 neutrino detection systems: Nova and Minor. The following neutrino experiments involving nuclear reactors: Chooz (France), Daya-bay (China), Reno (Korea) and Angra (Brazil) have also been reviewed. This document is made up of the slides of the presentations

  10. Molybdenum solar neutrino experiment

    International Nuclear Information System (INIS)

    Wolfsberg, K.; Cowan, G.A.; Bryant, E.A.

    1984-01-01

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

  11. Thermal dark matter through the Dirac neutrino portal

    Science.gov (United States)

    Batell, Brian; Han, Tao; McKeen, David; Haghi, Barmak Shams Es

    2018-04-01

    We study a simple model of thermal dark matter annihilating to standard model neutrinos via the neutrino portal. A (pseudo-)Dirac sterile neutrino serves as a mediator between the visible and the dark sectors, while an approximate lepton number symmetry allows for a large neutrino Yukawa coupling and, in turn, efficient dark matter annihilation. The dark sector consists of two particles, a Dirac fermion and complex scalar, charged under a symmetry that ensures the stability of the dark matter. A generic prediction of the model is a sterile neutrino with a large active-sterile mixing angle that decays primarily invisibly. We derive existing constraints and future projections from direct detection experiments, colliders, rare meson and tau decays, electroweak precision tests, and small scale structure observations. Along with these phenomenological tests, we investigate the consequences of perturbativity and scalar mass fine tuning on the model parameter space. A simple, conservative scheme to confront the various tests with the thermal relic target is outlined, and we demonstrate that much of the cosmologically-motivated parameter space is already constrained. We also identify new probes of this scenario such as multibody kaon decays and Drell-Yan production of W bosons at the LHC.

  12. The neutrino mirror

    International Nuclear Information System (INIS)

    Vannucci, F.

    2003-09-01

    The neutrino is not an elementary particle like others, it is the most stunning of all: the neutrino is undetectable by itself, we have only indirect evidences of its existence, but the neutrino is essential to explain the weak interaction, to understand why matter triumphed over anti-matter just after the Big-bang, or to solve the riddle of the hidden mass of the universe. This book is a popular work dedicated to the neutrino from its discovery in beta decays to the most recent theories such as neutrino oscillations, and via the worldwide experiments dedicated to the study of the neutrinos. (A.C.)

  13. Lepton asymmetry, neutrino spectral distortions, and big bang nucleosynthesis

    Science.gov (United States)

    Grohs, E.; Fuller, George M.; Kishimoto, C. T.; Paris, Mark W.

    2017-03-01

    We calculate Boltzmann neutrino energy transport with self-consistently coupled nuclear reactions through the weak-decoupling-nucleosynthesis epoch in an early universe with significant lepton numbers. We find that the presence of lepton asymmetry enhances processes which give rise to nonthermal neutrino spectral distortions. Our results reveal how asymmetries in energy and entropy density uniquely evolve for different transport processes and neutrino flavors. The enhanced distortions in the neutrino spectra alter the expected big bang nucleosynthesis light element abundance yields relative to those in the standard Fermi-Dirac neutrino distribution cases. These yields, sensitive to the shapes of the neutrino energy spectra, are also sensitive to the phasing of the growth of distortions and entropy flow with time/scale factor. We analyze these issues and speculate on new sensitivity limits of deuterium and helium to lepton number.

  14. Neutrino mass, a status report

    International Nuclear Information System (INIS)

    Robertson, R.G.H.

    1993-01-01

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

  15. Experimental Neutrino Physics: Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Lane, Charles E.; Maricic, Jelena

    2012-09-05

    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.

  16. Big bang nucleosynthesis with Gaussian inhomogeneous neutrino degeneracy

    International Nuclear Information System (INIS)

    Stirling, Spencer D.; Scherrer, Robert J.

    2002-01-01

    We consider the effect of inhomogeneous neutrino degeneracy on big bang nucleosynthesis for the case where the distribution of neutrino chemical potentials is given by a Gaussian. The chemical potential fluctuations are taken to be isocurvature, so that only inhomogeneities in the electron chemical potential are relevant. Then the final element abundances are a function only of the baryon-photon ratio η, the effective number of additional neutrinos ΔN ν , the mean electron neutrino degeneracy parameter ξ-bar, and the rms fluctuation of the degeneracy parameter, σ ξ . We find that for fixed η, ΔN ν , and ξ-bar, the abundances of 4 He, D, and 7 Li are, in general, increasing functions of σ ξ . Hence, the effect of adding a Gaussian distribution for the electron neutrino degeneracy parameter is to decrease the allowed range for η. We show that this result can be generalized to a wide variety of distributions for ξ

  17. Neutrino Physics at Drexel

    Energy Technology Data Exchange (ETDEWEB)

    Lane, Charles [Drexel Univ., Philadelphia, PA (United States); Dolinski, Michelle [Drexel Univ., Philadelphia, PA (United States); Neilson, Russell [Drexel Univ., Philadelphia, PA (United States)

    2017-07-11

    Our primary goal is to improve the understanding of the properties and interactions of neutrinos. We are pursuing this by means of the DUNE long-baseline and PROSPECT short-baseline neutrino experiments. For DUNE, a neutrino beam from Fermilab will be detected at the SURF facility in South Dakota, with the aim of determining the neutrino mass hierarchy (the mass ordering of neutrino flavors), and a measurement or limit on CP-violation via neutrinos. Our near-term experimental goal is to improve the characterization of the neutrino beam by measurements of muons produced as a byproduct of neutrino beam generation, to quantify the beam composition and flux. The short-range neutrino program has the aim of using the HFIR reactor at Oak Ridge as a neutrino source, with a detector placed nearby to find if there are short-distance oscillations to sterile neutrino flavors, and to resolve the 'reactor neutrino spectral anomaly' which has shown up as an unexplained 'bump' in the neutrino energy spectrum in recent experiments.

  18. Dilaton could affect abundance of dark matter particles

    CERN Multimedia

    2007-01-01

    "The amount of dark matter left over from the early universe may be less than previously believed. new research shows that the "relic abundance" of stable dark matter particles such as the neutralino may be reduced as compared to standard cosmology theories due to the effects of the "dilaton", a particle with zero spin in the gravitational sector of strings." (1 page)

  19. Stau relic density at the big-bang nucleosynthesis era in the coannihilation scenario and a solution to the Li7 problem

    Science.gov (United States)

    Jittoh, Toshifumi; Kohri, Kazunori; Koike, Masafumi; Sato, Joe; Shimomura, Takashi; Yamanaka, Masato

    2010-12-01

    We calculate the relic density of stau at the big-bang nucleosynthesis era in the coannihilation scenario of the minimal supersymmetric standard model. In this scenario, stau can be long lived and have significance in the remediation of light elements abundances. The freeze-out of stau is corroborated by solving the Boltzmann equation numerically, and the parameter dependence of the relic density is investigated. The possibility of solving the Li7 problem is examined by taking account into the long-lived stau. By adopting an observational value of Li7 in [J. Meléndez and I. Ramírez, Astrophys. J. 615, L33 (2004).ASJOAB0004-637X10.1086/425962], we get minimal supersymmetric standard model parameter space in which abundances of both dark matter and all of the light elements are reproduced in accordance with observations. We also address the influence of intergenerational mixing on our calculation.

  20. arXiv Squeezed relic photons beyond the horizon

    CERN Document Server

    Giovannini, Massimo

    2017-11-14

    Owing to the analogy with the ordinary photons in the visible range of the electromagnetic spectrum, the Glauber theory is generalized to address the quantum coherence of the gauge field fluctuations parametrically amplified during an inflationary stage of expansion. The first and second degrees of quantum coherence of relic photons are then computed beyond the effective horizon defined by the evolution of the susceptibility. In the zero-delay limit the Hanbury Brown-Twiss correlations exhibit a super-Poissonian statistics which is however different from the conventional results of the single-mode approximation customarily employed, in quantum optics, to classify the coherence properties of visible light. While in the case of large-scale curvature perturbations the degrees of quantum coherence coincide with the naive expectation of the single-mode approximation, the net degree of second-order coherence computed for the relic photons diminishes thanks to the effect of the polarizations. We suggest that the Han...

  1. The Neutrinos Saga

    International Nuclear Information System (INIS)

    La Souchere, Marie-Christine de; Moran, John

    2009-04-01

    The author proposes a history of the discovery and study of neutrinos. This history starts shortly after the discovery of radioactivity in 1896 with the observation of an inhomogeneous deceleration of electrons in the radioactive source which raised an issue of shortage of energy. Pauli then introduced the idea of a ghost particle which could preserve the principle of energy conservation and also the issue of statistics related to the laws of quantum mechanics. Works by the Joliot-Curies and Chadwick resulted in the identification of a neutral particle, first called a neutron, and then neutrino. The author then reports experiments performed to highlight neutrinos, and to identify different forms of neutrinos: muon, tau, lepton. She also addresses questions raised by solar neutrinos, experiments proving the metamorphosis of electron neutrinos into muon neutrinos. She discusses the interest of neutrino as cosmic messengers as they are emitted by various cosmic events, and also as a way to study dark matter

  2. Ghost basis for neutrino

    International Nuclear Information System (INIS)

    Novello, M.

    1976-07-01

    A class of solutions of DIRAC'S equation in gravitational fields for ghost neutrinos is given. Comments are restricted to the neutrino cosmological model recently found by M. Novello e I.D. Soares [pt

  3. Cosmological constraints on the amplitude of relic gravitational waves

    International Nuclear Information System (INIS)

    Novosyadlij, B.; Apunevich, S.

    2005-01-01

    The evolution of the amplitude of relic gravitational waves (RGW) generated in early Universe has been analyzed. The analytical approximation is presented for angular power spectrum of cosmic microwave background anisotropies caused by gravitational waves through Sachs-Wolfe effect. The estimate of the most probable value for this amplitude was obtained on the basis of observation data on cosmic microwave background anisotropies from COBE, WMAP and BOOMERanG experiments along with large-scale structure observations

  4. Could unstable relic particles distort the microwave background radiation?

    International Nuclear Information System (INIS)

    Dar, A.; Loeb, A.; Nussinov, S.

    1989-01-01

    Three general classes of possible scenarios for the recently reported distortion of the microwave background radiation (MBR) via decaying relic weakly interacting particles are analyzed. The analysis shows that such particles could not reheat the universe and cause the spectral distortion of the MBR. Gravitational processes such as the early formation of massive black holes may still be plausible energy sources for producing the reported spectral distortion of the MBR at an early cosmological epoch. 24 references

  5. Determination of absolute neutrino masses from Z-bursts

    International Nuclear Information System (INIS)

    Fodor, Z.

    2001-05-01

    Ultrahigh energy neutrinos (UHEν) scatter on cosmological relic neutrinos (Rν) producing Z bosons, which can decay hadronically producing protons (Z-burst). We compare the predicted proton spectrum with the observed ultrahigh energy cosmic ray (UHECR) spectrum and determine the mass of the heaviest Rν via a maximum likelihood analysis. Our mass prediction depends on the origin of the power-like part of the UHECR spectrum: m ν = 2.34 -0.84 +1.29 eV for Galactic halo and 0.26 -0.14 +0.20 eV for extragalactic (EG) origin. The second mass, with a lower bound of 0.06 eV on the 95% confidence level (CL), is compatible with a hierarchical ν mass scenario with the largest mass suggested by the atmospheric ν oscillation. The necessary UHEν flux is compatible with present upper limits and should be detected in the near future. (orig.)

  6. Again on neutrino oscillations

    International Nuclear Information System (INIS)

    Bilenky, S.M.; Pontecorvo, B.

    1976-01-01

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

  7. Leptogenesis and neutrino masses

    International Nuclear Information System (INIS)

    Pluemacher, M.

    2004-01-01

    Thermal leptogenesis explains the baryon asymmetry of the universe by the out-of-equilibrium decays of heavy right-handed neutrinos. In the minimal seesaw model this leads to interesting implications for light neutrino properties. In particular, quasi-degenerate light neutrino masses are incompatible with leptogenesis. An upper bound on light neutrino masses of 0.1 eV can be derived, which will be tested by forthcoming laboratory experiments and cosmology. (author)

  8. Neutrino masses and mixings

    International Nuclear Information System (INIS)

    Wolfenstein, L.

    1991-01-01

    Theoretical prejudices, cosmology, and neutrino oscillation experiments all suggest neutrino mass are far below present direct experimental limits. Four interesting scenarios and their implications are discussed: (1) a 17 keV ν τ , (2) a 30 ev ν τ making up the dark matter, (3) a 10 -3 ev ν μ to solve the solar neutrino problem, and (4) a three-neutrino MSW solution

  9. Geo-neutrino Observation

    International Nuclear Information System (INIS)

    Dye, S. T.; Alderman, M.; Batygov, M.; Learned, J. G.; Matsuno, S.; Mahoney, J. M.; Pakvasa, S.; Rosen, M.; Smith, S.; Varner, G.; McDonough, W. F.

    2009-01-01

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

  10. Towards neutrino astronomy

    International Nuclear Information System (INIS)

    Lagage, P.O.; Spiro, M.

    1985-01-01

    Neutrino sources are numerous and varied; the sun, a supernova explosion, the cosmic radiation interaction with interstellar medium are neutrino or antineutrino sources. The aim of this article is to overview the international projects of neutrino detection while giving the preference to the experimental side of the detection [fr

  11. Neutrino disintegration of deuterium

    International Nuclear Information System (INIS)

    Ying, S.; Haxton, W.; Henley, E.M.

    1989-01-01

    We calculate the rate of both neutral- and charged-current neutrino and antineutrino disintegration of deuterium. These rates are of interest for solar 8 B and hep ( 3 He + p) spectra and supernovae neutrinos, and are relevant for the Sudbury Neutrino Observatory (SNO)

  12. Reconstructing Neutrino Mass Spectrum

    OpenAIRE

    Smirnov, A. Yu.

    1999-01-01

    Reconstruction of the neutrino mass spectrum and lepton mixing is one of the fundamental problems of particle physics. In this connection we consider two central topics: (i) the origin of large lepton mixing, (ii) possible existence of new (sterile) neutrino states. We discuss also possible relation between large mixing and existence of sterile neutrinos.

  13. Solar neutrinos and gravity

    International Nuclear Information System (INIS)

    Kuo, T.K.

    2001-01-01

    We review the possibility that the solar neutrino problem can be explained by neutrinos violating the equivalence principle. It is found that such a scenario can be ruled out when one takes into account data from high energy accelerator neutrino experiments

  14. CERN: Neutrino facelift

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1991-11-15

    With the termination this summer of the CHARM II neutrino experiment at the SPS proton synchrotron, CERN's 30- year tradition of neutrino physics came to a temporary halt. However with these enigmatic particles playing a vital role in today's Standard Model but continually reluctant to give up all their secrets, neutrino physics will continue to be in the forefront of this research.

  15. Neutrino oscillations and neutrino-electron scattering

    International Nuclear Information System (INIS)

    Kayser, B.; Rosen, S.P.

    1980-10-01

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

  16. Neutrino observations from the Sudbury Neutrino Observatory

    Energy Technology Data Exchange (ETDEWEB)

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

    2001-09-24

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

  17. Neutrino Observations from the Sudbury Neutrino Observatory

    Science.gov (United States)

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

    2001-09-24

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

  18. Frontiers in neutrino physics - Transparencies

    International Nuclear Information System (INIS)

    Akhmedov, E.; Balantekin, B.; Conrad, J.; Engel, J.; Fogli, G.; Giunti, C.; Espinoza, C.; Lasserre, T.; Lazauskas, R.; Lhuiller, D.; Lindner, M.; Martinez-Pinedo, G.; Martini, M.; McLaughlin, G.; Mirizzi, A.; Pehlivan, Y.; Petcov, S.; Qian, Y.; Serenelli, A.; Stancu, I.; Surman, R.; Vaananen, D.; Vissani, F.; Vogel, P.

    2012-01-01

    This document gathers the slides of the presentations. The purpose of the conference was to discuss the last advances in neutrino physics. The presentations dealt with: -) the measurement of the neutrino velocity, -) neutrino oscillations, -) anomaly in solar models and neutrinos, -) double beta decay, -) self refraction of neutrinos, -) cosmic neutrinos, -) antineutrino spectra from reactors, and -) some aspects of neutrino physics with radioactive ion beams. (A.C.)

  19. LSND neutrino oscillation results

    International Nuclear Information System (INIS)

    Louis, W.C.

    1996-01-01

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

  20. Neutrino book

    International Nuclear Information System (INIS)

    Spiro, Michel

    1995-01-01

    André Rousset's book (in French - Gargamelle et les Courants Neutres - Ecole des Mines de Paris) tells the story of Gargamelle and the discovery at CERN in 1973 of neutral currents, the cornerstone of the electroweak theory. This vital discovery helped to give credence to the Standard Model of particle physics. Rousset is both an observer and one of the key figures in the story. His book is lively and well documented; in it he uses archive material to ensure the accuracy of his information on dates, choices and decisions. After an introduction to particle physics which puts into perspective the electroweak theory unifying weak and electromagnetic interactions, Rousset comes straight to the point. From the late 1950s onwards he was involved in the construction of the first heavy liquid bubble chambers by the BP1, BP2 and BP3 teams at the Ecole Polytechnique in Paris. For Gargamelle a bigger laboratory was needed, and it was at the CEA (French Atomic Energy Commission) in Saclay that the chamber was designed by teams from the Saturne accelerator and the Ecole Polytechnique. However, the decision to build Gargamelle was taken in 1965 through the impetus of André Lagarrigue, in defiance of the normal CERN procedures. Gargamelle was then in competition with the other big bubble chamber project, BEBC; was it really necessary to build two big chambers? The decision by Francis Perrin and the CEA to contribute ''generously'' to the project was probably what swung the decision. Construction took five years, during which many problems were encountered, right up to the fault in the main part of the chamber which caused delays and, a few years later, was to prove fatal to the detector. As Rousset correctly states, Gargamelle was probably the first big detector designed to be built on industrial lines, in direct cooperation with industry. The reward: the first neutrino interaction was photographed on 28 January 1971

  1. Case for neutrino oscillations

    International Nuclear Information System (INIS)

    Ramond, P.

    1982-01-01

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

  2. Sudbury neutrino observatory proposal

    International Nuclear Information System (INIS)

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

    1987-10-01

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

  3. Supernova nucleosynthesis and the physics of neutrino oscillation

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-11-20

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

  4. Supernova nucleosynthesis and the physics of neutrino oscillation

    Science.gov (United States)

    Kajino, Toshitaka

    2012-11-01

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

  5. Minimalistic Neutrino Mass Model

    CERN Document Server

    De Gouvêa, A; Gouvea, Andre de

    2001-01-01

    We consider the simplest model which solves the solar and atmospheric neutrino puzzles, in the sense that it contains the smallest amount of beyond the Standard Model ingredients. The solar neutrino data is accounted for by Planck-mass effects while the atmospheric neutrino anomaly is due to the existence of a single right-handed neutrino at an intermediate mass scale between 10^9 GeV and 10^14 GeV. Even though the neutrino mixing angles are not exactly predicted, they can be naturally large, which agrees well with the current experimental situation. Furthermore, the amount of lepton asymmetry produced in the early universe by the decay of the right-handed neutrino is very predictive and may be enough to explain the current baryon-to-photon ratio if the right-handed neutrinos are produced out of thermal equilibrium. One definitive test for the model is the search for anomalous seasonal effects at Borexino.

  6. Neutrinos (1/3)

    CERN Multimedia

    CERN. Geneva

    2013-01-01

    The neutrino, the lightest and most weakly interacting particle of the Standard Model has revealed itself as the messenger of very exciting news in particle physics: there is Physics Beyond the Standard Model. All this thanks to the quantum-mechanical phenomenon of flavour oscillations which is intrinsically connected to the question of neutrino mass and which has been observed in neutrinos produced in natural sources, like the Sun and the Earth's atmosphere, as well as with human made neutrino beams at accelerator and reactors. The purpose of these lectures is to overview some aspects of the phenomenology of massive neutrinos. I will present the simplest extensions for adding neutrino masses to the SM, and then I will describe the phenomenology associated with neutrino oscillations in vacuum and in matter and its present signatures.

  7. Light sterile neutrino sensitivity at the nuSTORM facility

    CERN Document Server

    Adey, D; Ankenbrandt, C.M.; Asfandiyarov, R.; Back, J.J.; Barker, G.; Baussan, E.; Bayes, R.; Bhadra, S.; Blackmore, V.; Blondel, A.; Bogacz, S.A.; Booth, C.; Boyd, S.B.; Bramsiepe, S.G.; Bravar, A.; Brice, S.J.; Bross, A.D.; Cadoux, F.; Cease, H.; Cervera, A.; Cobb, J.; Colling, D.; Coloma, P.; Coney, L.; Dobbs, A.; Dobson, J.; Donini, A.; Dornan, P.; Dracos, M.; Dufour, F.; Edgecock, R.; Geelhoed, M.; Uchida, M.A.; Ghosh, T.; Gomez-Cadenas, J.J.; de Gouvea, A.; Haesler, A.; Hanson, G.; Harrison, P.F.; Hartz, M.; Hernandez, P.; Hernando Morata, J.A.; Hodgson, P.; Huber, P.; Izmaylov, A.; Karadzhov, Y.; Kobilarcik, T.; Kopp, J.; Kormos, L.; Korzenev, A.; Kuno, Y.; Kurup, A.; Kyberd, P.; Lagrange, J.B.; Laing, A.; Liu, A.; Link, J.M.; Long, K.; Mahn, K.; Mariani, C.; Martin, C.; Martin, J.; McCauley, N.; McDonald, K.T.; Mena, O.; Mishra, S.R.; Mokhov, N.; Morfin, J.; Mori, Y.; Murray, W.; Neuffer, D.; Nichol, R.; Noah, E.; Palmer, M.A.; Parke, S.; Pascoli, S.; Pasternak, J.; Plunkett, R.; Popovic, M.; Ratoff, P.; Ravonel, M.; Rayner, M.; Ricciardi, S.; Rogers, C.; Rubinov, P.; Santos, E.; Sato, A.; Sen, T.; Scantamburlo, E.; Sedgbeer, J.K.; Smith, D.R.; Smith, P.J.; Sobczyk, J.T.; Sby, L.; Soler, F.J.P.; Sorel, M.; Snopok, P.; Stamoulis, P.; Stanco, L.; Striganov, S.; Tanaka, H.A.; Taylor, I.J.; Touramanis, C.; Tunnell, C.D.; Uchida, Y.; Vassilopoulos, N.; Wascko, M.O.; Weber, A.; Wilking, M.J.; Wildner, E.; Winter, W.

    2014-01-01

    A facility that can deliver beams of electron and muon neutrinos from the decay of a stored muon beam has the potential to unambiguously resolve the issue of the evidence for light sterile neutrinos that arises in short-baseline neutrino oscillation experiments and from estimates of the effective number of neutrino flavors from fits to cosmological data. In this paper, we show that the nuSTORM facility, with stored muons of 3.8 GeV/c $\\pm$ 10%, will be able to carry out a conclusive muon neutrino appearance search for sterile neutrinos and test the LSND and MiniBooNE experimental signals with 10$\\sigma$ sensitivity, even assuming conservative estimates for the systematic uncertainties. This experiment would add greatly to our knowledge of the contribution of light sterile neutrinos to the number of effective neutrino flavors from the abundance of primordial helium production and from constraints on neutrino energy density from the cosmic microwave background. The appearance search is complemented by a simulta...

  8. Supernova neutrinos, giant resonances, and nucleosynthesis

    International Nuclear Information System (INIS)

    Haxton, W.

    1990-01-01

    Almost all of the 3·10 53 ergs liberated in a core collapse supernova is radiated as neutrinos by the cooling neutron star. The neutrinos can excite nuclei in the mantle of the star by their neutral and charged current reactions. I argue that the resulting spallation reactions are an important nucleosynthesis mechanism that may be responsible for the galactic abundances of 7 Li, 11 B, 19 F, 138 La, 180 Ta, and approximately a dozen other light nuclei. 18 refs., 1 fig., 1 tab

  9. Neutrino physics with JUNO

    Science.gov (United States)

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

    2016-03-01

    The Jiangmen Underground Neutrino Observatory (JUNO), a 20 kton multi-purpose underground liquid scintillator detector, was proposed with the determination of the neutrino mass hierarchy (MH) as a primary physics goal. The excellent energy resolution and the large fiducial volume anticipated for the JUNO detector offer exciting opportunities for addressing many important topics in neutrino and astro-particle physics. In this document, we present the physics motivations and the anticipated performance of the JUNO detector for various proposed measurements. Following an introduction summarizing the current status and open issues in neutrino physics, we discuss how the detection of antineutrinos generated by a cluster of nuclear power plants allows the determination of the neutrino MH at a 3-4σ significance with six years of running of JUNO. The measurement of antineutrino spectrum with excellent energy resolution will also lead to the precise determination of the neutrino oscillation parameters {{sin}}2{θ }12, {{Δ }}{m}212, and | {{Δ }}{m}{ee}2| to an accuracy of better than 1%, which will play a crucial role in the future unitarity test of the MNSP matrix. The JUNO detector is capable of observing not only antineutrinos from the power plants, but also neutrinos/antineutrinos from terrestrial and extra-terrestrial sources, including supernova burst neutrinos, diffuse supernova neutrino background, geoneutrinos, atmospheric neutrinos, and solar neutrinos. As a result of JUNO's large size, excellent energy resolution, and vertex reconstruction capability, interesting new data on these topics can be collected. For example, a neutrino burst from a typical core-collapse supernova at a distance of 10 kpc would lead to ˜5000 inverse-beta-decay events and ˜2000 all-flavor neutrino-proton ES events in JUNO, which are of crucial importance for understanding the mechanism of supernova explosion and for exploring novel phenomena such as collective neutrino oscillations

  10. Pathlength distributions of atmospheric neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Gaisser, T.K.; Stanev, Todor

    1999-01-01

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

  11. Properties of neutrinos: Recent results

    International Nuclear Information System (INIS)

    Robertson, R.G.H.

    1987-01-01

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

  12. The case for mixed dark matter from sterile neutrinos

    International Nuclear Information System (INIS)

    Lello, Louis; Boyanovsky, Daniel

    2016-01-01

    Sterile neutrinos are SU(2) singlets that mix with active neutrinos via a mass matrix, its diagonalization leads to mass eigenstates that couple via standard model vertices. We study the cosmological production of heavy neutrinos via standard model charged and neutral current vertices under a minimal set of assumptions: i) the mass basis contains a hierarchy of heavy neutrinos , ii) these have very small mixing angles with the active (flavor) neutrinos, iii) standard model particles, including light (active-like) neutrinos are in thermal equilibrium. If kinematically allowed, the same weak interaction processes that produce active-like neutrinos also produce the heavier species. We introduce the quantum kinetic equations that describe their production, freeze out and decay and discuss the various processes that lead to their production in a wide range of temperatures assessing their feasibility as dark matter candidates. The final distribution function at freeze-out is a mixture of the result of the various production processes. We identify processes in which finite temperature collective excitations may lead to the production of the heavy species. As a specific example, we consider the production of heavy neutrinos in the mass range M h ∼< 140 MeV from pion decay shortly after the QCD crossover including finite temperature corrections to the pion form factors and mass. We consider the different decay channels that allow for the production of heavy neutrinos showing that their frozen distribution functions exhibit effects from ''kinematic entanglement'' and argue for their viability as mixed dark matter candidates. We discuss abundance, phase space density and stability constraints and argue that heavy neutrinos with lifetime τ> 1/ H 0 freeze out of local thermal equilibrium, and conjecture that those with lifetimes τ || 1/ H 0 may undergo cascade decay into lighter DM candidates and/or inject non-LTE neutrinos into the cosmic neutrino

  13. The case for mixed dark matter from sterile neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Lello, Louis; Boyanovsky, Daniel, E-mail: lal81@pitt.edu, E-mail: boyan@pitt.edu [Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260 (United States)

    2016-06-01

    Sterile neutrinos are SU(2) singlets that mix with active neutrinos via a mass matrix, its diagonalization leads to mass eigenstates that couple via standard model vertices. We study the cosmological production of heavy neutrinos via standard model charged and neutral current vertices under a minimal set of assumptions: i) the mass basis contains a hierarchy of heavy neutrinos , ii) these have very small mixing angles with the active (flavor) neutrinos, iii) standard model particles, including light (active-like) neutrinos are in thermal equilibrium. If kinematically allowed, the same weak interaction processes that produce active-like neutrinos also produce the heavier species. We introduce the quantum kinetic equations that describe their production, freeze out and decay and discuss the various processes that lead to their production in a wide range of temperatures assessing their feasibility as dark matter candidates. The final distribution function at freeze-out is a mixture of the result of the various production processes. We identify processes in which finite temperature collective excitations may lead to the production of the heavy species. As a specific example, we consider the production of heavy neutrinos in the mass range M {sub h} ∼< 140 MeV from pion decay shortly after the QCD crossover including finite temperature corrections to the pion form factors and mass. We consider the different decay channels that allow for the production of heavy neutrinos showing that their frozen distribution functions exhibit effects from ''kinematic entanglement'' and argue for their viability as mixed dark matter candidates. We discuss abundance, phase space density and stability constraints and argue that heavy neutrinos with lifetime τ> 1/ H {sub 0} freeze out of local thermal equilibrium, and conjecture that those with lifetimes τ || 1/ H {sub 0} may undergo cascade decay into lighter DM candidates and/or inject non-LTE neutrinos into the

  14. Solar neutrino observations and neutrino oscillations

    International Nuclear Information System (INIS)

    Kuo, T.K.; Pantaleone, J.

    1990-01-01

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

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

    International Nuclear Information System (INIS)

    Blennow, Mattias; Edsjö, Joakim; Ohlsson, Tommy

    2011-01-01

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

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

    International Nuclear Information System (INIS)

    Blennow, Mattias; Edsjoe, Joakim; Ohlsson, Tommy

    2006-01-01

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

  17. Exploration and implementation of ontology-based cultural relic knowledge map integration platform

    Science.gov (United States)

    Yang, Weiqiang; Dong, Yiqiang

    2018-05-01

    To help designers to better carry out creative design and improve the ability of searching traditional cultural relic information, the ontology-based knowledge map construction method was explored and an integrated platform for cultural relic knowledge map was developed. First of all, the construction method of the ontology of cultural relics was put forward, and the construction of the knowledge map of cultural relics was completed based on the constructed cultural relic otology. Then, a personalized semantic retrieval framework for creative design was proposed. Finally, the integrated platform of the knowledge map of cultural relics was designed and realized. The platform was divided into two parts. One was the foreground display system, which was used for designers to search and browse cultural relics. The other was the background management system, which was for cultural experts to manage cultural relics' knowledge. The research results showed that the platform designed could improve the retrieval ability of cultural relic information. To sum up, the platform can provide a good support for the designer's creative design.

  18. Cold dark matter plus not-so-clumpy dark relics

    International Nuclear Information System (INIS)

    Diamanti, Roberta; Ando, Shin'ichiro; Weniger, Christoph; Gariazzo, Stefano; Mena, Olga

    2017-01-01

    Various particle physics models suggest that, besides the (nearly) cold dark matter that accounts for current observations, additional but sub-dominant dark relics might exist. These could be warm, hot, or even contribute as dark radiation. We present here a comprehensive study of two-component dark matter scenarios, where the first component is assumed to be cold, and the second is a non-cold thermal relic. Considering the cases where the non-cold dark matter species could be either a fermion or a boson, we derive consistent upper limits on the non-cold dark relic energy density for a very large range of velocity dispersions, covering the entire range from dark radiation to cold dark matter. To this end, we employ the latest Planck Cosmic Microwave Background data, the recent BOSS DR11 and other Baryon Acoustic Oscillation measurements, and also constraints on the number of Milky Way satellites, the latter of which provides a measure of the suppression of the matter power spectrum at the smallest scales due to the free-streaming of the non-cold dark matter component. We present the results on the fraction f ncdm of non-cold dark matter with respect to the total dark matter for different ranges of the non-cold dark matter masses. We find that the 2σ limits for non-cold dark matter particles with masses in the range 1–10 keV are f ncdm ≤0.29 (0.23) for fermions (bosons), and for masses in the 10–100 keV range they are f ncdm ≤0.43 (0.45), respectively.

  19. Cold dark matter plus not-so-clumpy dark relics

    Energy Technology Data Exchange (ETDEWEB)

    Diamanti, Roberta; Ando, Shin' ichiro; Weniger, Christoph [GRAPPA, Institute of Physics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam (Netherlands); Gariazzo, Stefano; Mena, Olga, E-mail: r.diamanti@uva.nl, E-mail: s.ando@uva.nl, E-mail: gariazzo@to.infn.it, E-mail: omena@ific.uv.es, E-mail: c.weniger@uva.nl [Instituto de Física Corpuscular (IFIC), CSIC-Universitat de Valencia, Apartado de Correos 22085, E-46071, Valencia (Spain)

    2017-06-01

    Various particle physics models suggest that, besides the (nearly) cold dark matter that accounts for current observations, additional but sub-dominant dark relics might exist. These could be warm, hot, or even contribute as dark radiation. We present here a comprehensive study of two-component dark matter scenarios, where the first component is assumed to be cold, and the second is a non-cold thermal relic. Considering the cases where the non-cold dark matter species could be either a fermion or a boson, we derive consistent upper limits on the non-cold dark relic energy density for a very large range of velocity dispersions, covering the entire range from dark radiation to cold dark matter. To this end, we employ the latest Planck Cosmic Microwave Background data, the recent BOSS DR11 and other Baryon Acoustic Oscillation measurements, and also constraints on the number of Milky Way satellites, the latter of which provides a measure of the suppression of the matter power spectrum at the smallest scales due to the free-streaming of the non-cold dark matter component. We present the results on the fraction f {sub ncdm} of non-cold dark matter with respect to the total dark matter for different ranges of the non-cold dark matter masses. We find that the 2σ limits for non-cold dark matter particles with masses in the range 1–10 keV are f {sub ncdm}≤0.29 (0.23) for fermions (bosons), and for masses in the 10–100 keV range they are f {sub ncdm}≤0.43 (0.45), respectively.

  20. MINOS Sterile Neutrino Search

    Energy Technology Data Exchange (ETDEWEB)

    Koskinen, David Jason [Univ. College London, Bloomsbury (United Kingdom)

    2009-02-01

    The Main Injector Neutrino Oscillation Search (MINOS) is a long-baseline accelerator neutrino experiment designed to measure properties of neutrino oscillation. Using a high intensity muon neutrino beam, produced by the Neutrinos at Main Injector (NuMI) complex at Fermilab, MINOS makes two measurements of neutrino interactions. The first measurement is made using the Near Detector situated at Fermilab and the second is made using the Far Detector located in the Soudan Underground laboratory in northern Minnesota. The primary goal of MINOS is to verify, and measure the properties of, neutrino oscillation between the two detectors using the v μ→ Vτ transition. A complementary measurement can be made to search for the existence of sterile neutrinos; an oft theorized, but experimentally unvalidated particle. The following thesis will show the results of a sterile neutrino search using MINOS RunI and RunII data totaling ~2.5 x 1020 protons on target. Due to the theoretical nature of sterile neutrinos, complete formalism that covers transition probabilities for the three known active states with the addition of a sterile state is also presented.

  1. The ideal neutrino beams

    CERN Document Server

    Lindroos, Mats

    2009-01-01

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

  2. The ideal neutrino beams

    Science.gov (United States)

    Lindroos, Mats

    2009-06-01

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

  3. Sudbury Neutrino Observatory

    International Nuclear Information System (INIS)

    Beier, E.W.

    1992-03-01

    This document is a technical progress report on work performed at the University of Pennsylvania during the current year on the Sudbury Neutrino Observatory project. The motivation for the experiment is the measurement of neutrinos emitted by the sun. The Sudbury Neutrino Observatory (SNO) is a second generation dedicated solar neutrino experiment which will extend the results of our work with the Kamiokande II detector by measuring three reactions of neutrinos rather than the single reaction measured by the Kamiokande experiment. The collaborative project includes physicists from Canada, the United Kingdom, and the United States. Full funding for the construction of this facility was obtained in January 1990, and its construction is estimated to take five years. The motivation for the SNO experiment is to study the fundamental properties of neutrinos, in particular the mass and mixing parameters, which remain undetermined after decades of experiments in neutrino physics utilizing accelerators and reactors as sources of neutrinos. To continue the study of neutrino properties it is necessary to use the sun as a neutrino source. The long distance to the sun makes the search for neutrino mass sensitive to much smaller mass than can be studied with terrestrial sources. Furthermore, the matter density in the sun is sufficiently large to enhance the effects of small mixing between electron neutrinos and mu or tau neutrinos. This experiment, when combined with the results of the radiochemical 37 Cl and 71 Ga experiments and the Kamiokande II experiment, should extend our knowledge of these fundamental particles, and as a byproduct, improve our understanding of energy generation in the sun

  4. Higgs enhancement for the dark matter relic density

    Science.gov (United States)

    Harz, Julia; Petraki, Kalliopi

    2018-04-01

    We consider the long-range effect of the Higgs on the density of thermal-relic dark matter. While the electroweak gauge boson and gluon exchange have been previously studied, the Higgs is typically thought to mediate only contact interactions. We show that the Sommerfeld enhancement due to a 125 GeV Higgs can deplete TeV-scale dark matter significantly and describe how the interplay between the Higgs and other mediators influences this effect. We discuss the importance of the Higgs enhancement in the minimal supersymmetric standard model and its implications for experiments.

  5. Investigation of laser cleaning on bronze cultural relics

    International Nuclear Information System (INIS)

    Ling, Xiulan; Wang, Gao; Zhang, Chen

    2016-01-01

    The effects of laser cleaning on the corrosion layers of bronze cultural relics were studied using a pulsed fiber laser. The laser cleaning threshold value of the corrosion layers was obtained. It was found that the corrosion layer was removed successfully by employing a laser fluence value of 0.32 J cm −2 and scanning for three times. To obtain experimental evidence, laser con-focal scanning microscopy, scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS), laser induced breakdown spectroscopy (LIBS) and laser Raman spectroscopy were employed to investigate the cleaning efficiency of corrosion layers on specimens. (paper)

  6. Acquire information about neutrino parameters by detecting supernova neutrinos

    OpenAIRE

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

    2010-01-01

    We consider the supernova shock effects, the Mikheyev-Smirnov-Wolfenstein (MSW) effects, the collective effects, and the Earth matter effects in the detection of type II supernova neutrinos on the Earth. It is found that the event number of supernova neutrinos depends on the neutrino mass hierarchy, the neutrino mixing angle $\\theta_{13}$, and neutrino masses. Therefore, we propose possible methods to identify the mass hierarchy and acquire information about $\\theta_{13}$ and neutrino masses ...

  7. A combined treatment of neutrino decay and neutrino oscillations

    International Nuclear Information System (INIS)

    Lindner, Manfred; Ohlsson, Tommy; Winter, Walter

    2001-01-01

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

  8. Neutrino oscillations make their first appearance in OPERA

    CERN Multimedia

    CERN Bulletin

    2010-01-01

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

  9. Detecting supernova neutrinos in Daya Bay Neutrino Laboratory

    International Nuclear Information System (INIS)

    Huang Mingyang; Guo Xinheng; Yang Binglin

    2011-01-01

    While detecting supernova neutrinos in the Daya Bay neutrino laboratory, several supernova neutrino effects need to be considered, including the supernova shock effects, the neutrino collective effects, the Mikheyev-Smirnov-Wolfenstein (MSW) effects, and the Earth matter effects. The phenomena of neutrino oscillation is affected by the above effects. Using some ratios of the event numbers of different supernova neutrinos, we propose some possible methods to identify the mass hierarchy and acquire information about the neutrino mixing angle θ13 and neutrino masses. (authors)

  10. Acquiring information about neutrino parameters by detecting supernova neutrinos

    Science.gov (United States)

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

    2010-08-01

    We consider the supernova shock effects, the Mikheyev-Smirnov-Wolfenstein effects, the collective effects, and the Earth matter effects in the detection of type II supernova neutrinos on the Earth. It is found that the event number of supernova neutrinos depends on the neutrino mass hierarchy, the neutrino mixing angle θ13, and neutrino masses. Therefore, we propose possible methods to identify the mass hierarchy and acquire information about θ13 and neutrino masses by detecting supernova neutrinos. We apply these methods to some current neutrino experiments.

  11. Neutrinos and dark energy

    International Nuclear Information System (INIS)

    Schrempp, L.

    2008-02-01

    From the observed late-time acceleration of cosmic expansion arises the quest for the nature of Dark Energy. As has been widely discussed, the cosmic neutrino background naturally qualifies for a connection with the Dark Energy sector and as a result could play a key role for the origin of cosmic acceleration. In this thesis we explore various theoretical aspects and phenomenological consequences arising from non-standard neutrino interactions, which dynamically link the cosmic neutrino background and a slowly-evolving scalar field of the dark sector. In the considered scenario, known as Neutrino Dark Energy, the complex interplay between the neutrinos and the scalar field not only allows to explain cosmic acceleration, but intriguingly, as a distinct signature, also gives rise to dynamical, time-dependent neutrino masses. In a first analysis, we thoroughly investigate an astrophysical high energy neutrino process which is sensitive to neutrino masses. We work out, both semi-analytically and numerically, the generic clear-cut signatures arising from a possible time variation of neutrino masses which we compare to the corresponding results for constant neutrino masses. Finally, we demonstrate that even for the lowest possible neutrino mass scale, it is feasible for the radio telescope LOFAR to reveal a variation of neutrino masses and therefore to probe the nature of Dark Energy within the next decade. A second independent analysis deals with the recently challenged stability of Neutrino Dark Energy against the strong growth of hydrodynamic perturbations, driven by the new scalar force felt between neutrinos. Within the framework of linear cosmological perturbation theory, we derive the equation of motion of the neutrino perturbations in a model-independent way. This equation allows to deduce an analytical stability condition which translates into a comfortable upper bound on the scalar-neutrino coupling which is determined by the ratio of the densities in cold dark

  12. Neutrinos and dark energy

    Energy Technology Data Exchange (ETDEWEB)

    Schrempp, L.

    2008-02-15

    From the observed late-time acceleration of cosmic expansion arises the quest for the nature of Dark Energy. As has been widely discussed, the cosmic neutrino background naturally qualifies for a connection with the Dark Energy sector and as a result could play a key role for the origin of cosmic acceleration. In this thesis we explore various theoretical aspects and phenomenological consequences arising from non-standard neutrino interactions, which dynamically link the cosmic neutrino background and a slowly-evolving scalar field of the dark sector. In the considered scenario, known as Neutrino Dark Energy, the complex interplay between the neutrinos and the scalar field not only allows to explain cosmic acceleration, but intriguingly, as a distinct signature, also gives rise to dynamical, time-dependent neutrino masses. In a first analysis, we thoroughly investigate an astrophysical high energy neutrino process which is sensitive to neutrino masses. We work out, both semi-analytically and numerically, the generic clear-cut signatures arising from a possible time variation of neutrino masses which we compare to the corresponding results for constant neutrino masses. Finally, we demonstrate that even for the lowest possible neutrino mass scale, it is feasible for the radio telescope LOFAR to reveal a variation of neutrino masses and therefore to probe the nature of Dark Energy within the next decade. A second independent analysis deals with the recently challenged stability of Neutrino Dark Energy against the strong growth of hydrodynamic perturbations, driven by the new scalar force felt between neutrinos. Within the framework of linear cosmological perturbation theory, we derive the equation of motion of the neutrino perturbations in a model-independent way. This equation allows to deduce an analytical stability condition which translates into a comfortable upper bound on the scalar-neutrino coupling which is determined by the ratio of the densities in cold dark

  13. Study of electroweak vacuum stability from extended Higgs portal of dark matter and neutrinos

    Science.gov (United States)

    Ghosh, Purusottam; Saha, Abhijit Kumar; Sil, Arunansu

    2018-04-01

    We investigate the electroweak vacuum stability in an extended version of the Standard Model that incorporates two additional singlet scalar fields and three right-handed neutrinos. One of these extra scalars plays the role of dark matter, while the other scalar not only helps make the electroweak vacuum stable but also opens up the low-mass window of the scalar singlet dark matter (<500 GeV ). We consider the effect of large neutrino Yukawa coupling on the running of Higgs quartic coupling. We have analyzed the constraints on the model and identified the range of parameter space that is consistent with the neutrino mass, appropriate relic density, and direct search limits from the latest XENON 1T preliminary result as well as realized the stability of the electroweak vacuum up to the Planck scale.

  14. Three Dirac neutrinos

    International Nuclear Information System (INIS)

    Joshipura, A.S.; Rindani, S.D.

    1991-01-01

    The consequences of imposing an exact L e +L τ -L μ symmetry on a 6x6 matrix describing neutrino masses are discussed. The presence of right-handed neutrinos avoids the need of introducing any SU(2) Higgs triplet. Hence the conflict with the CERN LEP data on the Z width found in earlier models with L e +L τ -L μ symmetry is avoided. The L e +L τ -L μ symmetry provides an interesting realization of a recent proposal of Glashow to accommodate the 17-keV Dirac neutrino in the SU(2)xU(1) theory. All the neutrinos in this model are Dirac particles. The solar-neutrino problem can be solved in an extension of the model which generates a large (∼10 -11 μ B ) magnetic moment for the electron neutrino

  15. Neutrino mass matrix

    International Nuclear Information System (INIS)

    Strobel, E.L.

    1985-01-01

    Given the many conflicting experimental results, examination is made of the neutrino mass matrix in order to determine possible masses and mixings. It is assumed that the Dirac mass matrix for the electron, muon, and tau neutrinos is similar in form to those of the quarks and charged leptons, and that the smallness of the observed neutrino masses results from the Gell-Mann-Ramond-Slansky mechanism. Analysis of masses and mixings for the neutrinos is performed using general structures for the Majorana mass matrix. It is shown that if certain tentative experimental results concerning the neutrino masses and mixing angles are confirmed, significant limitations may be placed on the Majorana mass matrix. The most satisfactory simple assumption concerning the Majorana mass matrix is that it is approximately proportional to the Dirac mass matrix. A very recent experimental neutrino mass result and its implications are discussed. Some general properties of matrices with structure similar to the Dirac mass matrices are discussed

  16. Galactic neutrino communication

    Energy Technology Data Exchange (ETDEWEB)

    Learned, John G. [Department of Physics and Astronomy, University of Hawaii, 2505 Correa Road, Honolulu, HI 96822 (United States)], E-mail: jgl@phys.hawaii.edu; Pakvasa, Sandip [Department of Physics and Astronomy, University of Hawaii, 2505 Correa Road, Honolulu, HI 96822 (United States)], E-mail: pakvasa@phys.hawaii.edu; Zee, A. [Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106 (United States)], E-mail: zee@kitp.ucsb.edu

    2009-01-12

    We examine the possibility to employ neutrinos to communicate within the galaxy. We discuss various issues associated with transmission and reception, and suggest that the resonant neutrino energy near 6.3 PeV may be most appropriate. In one scheme we propose to make Z deg. particles in an overtaking e{sup +}-e{sup -} collider such that the resulting decay neutrinos are near the W{sup -} resonance on electrons in the laboratory. Information is encoded via time structure of the beam. In another scheme we propose to use a 30 PeV pion accelerator to create neutrino or anti-neutrino beams. The latter encodes information via the beam CP state as well as timing. Moreover the latter beam requires far less power, and can be accomplished with presently foreseeable technology. Such signals from an advanced civilization, should they exist, will be eminently detectable in existing neutrino detectors.

  17. Solar neutrino detection

    International Nuclear Information System (INIS)

    Miramonti, Lino

    2009-01-01

    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.

  18. Visible neutrino decay at DUNE

    Energy Technology Data Exchange (ETDEWEB)

    Coloma, Pilar [Fermilab; Peres, Orlando G. [ICTP, Trieste

    2017-05-09

    If the heaviest neutrino mass eigenstate is unstable, its decay modes could include lighter neutrino eigenstates. In this case part of the decay products could be visible, as they would interact at neutrino detectors via mixing. At neutrino oscillation experiments, a characteristic signature of such \\emph{visible neutrino decay} would be an apparent excess of events at low energies. We focus on a simple phenomenological model in which the heaviest neutrino decays as $\

  19. Improved determination of sterile neutrino dark matter spectrum

    International Nuclear Information System (INIS)

    Ghiglieri, J.; Laine, M.

    2015-01-01

    The putative recent indication of an unidentified 3.55 keV X-ray line in certain astrophysical sources is taken as a motivation for an improved theoretical computation of the cosmological abundance of 7.1 keV sterile neutrinos. If the line is interpreted as resulting from the decay of Warm Dark Matter, the mass and mixing angle of the sterile neutrino are known. Our computation then permits for a determination of the lepton asymmetry that is needed for producing the correct abundance via the Shi-Fuller mechanism, as well as for an estimate of the non-equilibrium spectrum of the sterile neutrinos. The latter plays a role in structure formation simulations. Results are presented for different flavour structures of the neutrino Yukawa couplings and for different types of pre-existing lepton asymmetries, accounting properly for the charge neutrality of the plasma and incorporating approximately hadronic contributions.

  20. Detecting Solar Neutrino Flare in Megaton and km3 detectors

    International Nuclear Information System (INIS)

    Fargion, Daniele; Di Giacomo, Paola

    2009-01-01

    To foresee a solar flare neutrino signal we infer its upper and lower bound. The upper bound was derived since a few years by general energy equipartition arguments on observed solar particle flare. The lower bound, the most compelling one for any guarantee neutrino signal, is derived by most recent records of hard Gamma bump due to solar flare on January 2005 (by neutral pion decay). Because neutral and charged pions (made by hadron scattering in the flare) are born on the same foot, their link is compelling: the observed gamma flux [Grechnev V.V. et al., (arXiv:0806.4424), Solar Physics, Vol. 1, October, (2008), 252] reflects into a corresponding one for the neutrinos, almost one to one. Moreover while gamma photons might be absorbed (in deep corona) or at least reduced inside the flaring plasma, the secondaries neutrino are not. So pion neutrinos should be even more abundant than gamma ones. Tens-hundred MeV neutrinos may cross undisturbed the whole Sun, doubling at least their rate respect a unique solar-side for gamma flare. Therefore we obtain minimal bounds opening a windows for neutrino astronomy, already at the edge of present but quite within near future Megaton neutrino detectors. Such detectors are considered mostly to reveal cosmic supernova background or rare Local Group (few Mpc) Supernovas events [Matthew D. Kistler et al. (0810.1959v1)]. However rarest (once a decade), brief (a few minutes) powerful solar neutrino 'flare' may shine and they may overcome by two to three order of magnitude the corresponding steady atmospheric neutrino noise on the Earth, leading in largest Neutrino detector at least to one or to meaning-full few events clustered signals. The voice of such a solar anti-neutrino flare component at a few tens MeVs may induce an inverse beta decay over a vanishing anti-neutrino solar background. Megaton or even inner ten Megaton Ice Cube detector at ten GeV threshold may also reveal traces in hardest energy of solar flares. Icecube

  1. Neutrino Physics at Fermilab

    International Nuclear Information System (INIS)

    Federspiel, F.; Garvey, G.; Louis, W.C.; Mills, G.B.; Tayloe, R.; Sandberg, V.; Sapp, B.; White, D.H.

    1999-01-01

    The Liquid Scintillator Neutrino Detector (LSND), located at the LANSCE (formerly LAMPF) linear accelerator at Los Alamos National Laboratory, has seen evidence for the oscillation of neutrinos, and hence neutrino mass. That discovery was the impetus for this LDRD project, begun in 1996. The goal of this project was to define the appropriate technologies to use in a follow up experiment and to set in place the requirements for such an experiment

  2. Neutrinos from gravitational collapse

    International Nuclear Information System (INIS)

    Mayle, R.; Wilson, J.R.; Schramm, D.N.

    1986-05-01

    Detailed calculations are made of the neutrino spectra emitted during gravitational collapse events (Type II supernovae). Those aspects of the neutrino signal which are relatively independent of the collapse model and those aspects which are sensitive to model details are discussed. The easier-to-detect high energy tail of the emitted neutrinos has been calculated using the Boltzmann equation which is compared with the result of the traditional multi-group flux limited diffusion calculations. 8 figs., 28 refs

  3. Beta rays and neutrinos

    International Nuclear Information System (INIS)

    Adams, S.F.

    1992-01-01

    It was over 30 years between the first observation of the enigmatic process of beta decay and the first postulation of the neutrino. It took a further 26 years until the first neutrino was detected and yet another 27 until the electroweak theory was confirmed by the discovery of W and Z particles. This article traces some of the puzzles and paradoxes associated with the history of the neutrino. (author)

  4. CERN: Neutrino facelift

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    With the termination this summer of the CHARM II neutrino experiment at the SPS proton synchrotron, CERN's 30- year tradition of neutrino physics came to a temporary halt. However with these enigmatic particles playing a vital role in today's Standard Model but continually reluctant to give up all their secrets, neutrino physics will continue to be in the forefront of this research

  5. Neutrinos in the Electron

    International Nuclear Information System (INIS)

    Koschmieder, E. L.

    2007-01-01

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

  6. Neutrino Oscillation Physics

    International Nuclear Information System (INIS)

    Kayser, Boris

    2014-01-01

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

  7. Neutrino properties from cosmology

    DEFF Research Database (Denmark)

    Hannestad, S.

    2013-01-01

    In recent years precision cosmology has become an increasingly powerful probe of particle physics. Perhaps the prime example of this is the very stringent cosmological upper bound on the neutrino mass. However, other aspects of neutrino physics, such as their decoupling history and possible non......-standard interactions, can also be probed using observations of cosmic structure. Here, I review the current status of cosmological bounds on neutrino properties and discuss the potential of future observations, for example by the recently approved EUCLID mission, to precisely measure neutrino properties....

  8. Solar neutrino experiments

    International Nuclear Information System (INIS)

    Hampel, W.

    1996-01-01

    The present status of experimental solar neutrino research is reviewed. Updated results from the Homestake, Kamiokande, GALLEX and SAGE detectors all show a deficit when compared to recent standard solar model calculations. Two of these detectors, GALLEX and SAGE, have recently been checked with artificial 51 Cr neutrino sources. It is shown that astrophysical scenarios to solve the solar neutrino problems are not favoured by the data. There is hope that the results of forthcoming solar neutrino experiments can provide the answers to the open questions. (author) 6 figs., 3 tabs., 36 refs

  9. Neutrino Oscillation Physics

    Energy Technology Data Exchange (ETDEWEB)

    Kayser, Boris [Fermilab (United States)

    2014-07-01

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

  10. Neutrinos in supernovae

    International Nuclear Information System (INIS)

    Cooperstein, J.

    1986-10-01

    The role of neutrinos in Type II supernovae is discussed. An overall view of the neutrino luminosity as expected theoretically is presented. The different weak interactions involved are assessed from the standpoint of how they exchange energy, momentum, and lepton number. Particular attention is paid to entropy generation and the path to thermal and chemical equilibration, and to the phenomenon of trapping. Various methods used to calculate the neutrino flows are considered. These include trapping and leakage schemes, distribution-averaged transfer, and multi-energy group methods. The information obtained from the neutrinos caught from Supernova 1987a is briefly evaluated. 55 refs., 7 figs

  11. Neutrinos in astrophysics

    CERN Document Server

    Rees, Martin J

    1980-01-01

    The amount of 4He synthesised in the "big bang" is sensitive to the early particle content and to the expansion rate. If there was indeed a "big bang", surprisingly strong conclusions can be drawn about the number of species of neutrinos, and about the possibility that such particles have non-zero rest mass. The dynamics of supernovae are sensitive to the det~ils of neutrino physics; such explosions would yield IO L-1053 ergs of -v IO Mev neutrinos, in a burst lasting a few milliseconds. Galactic nuclei, cosmic ray sources and other high energy cosmic phenomena could yield a low background of~ 10 Gev neutrinos.

  12. Question of neutrino mass

    International Nuclear Information System (INIS)

    Branco, G.C.; Senjanovic, G.

    1978-01-01

    We investigate the question of neutrino mass in theories in which neutrinos are four-component Dirac particles. Our analysis is done in the framework of left-right--symmetric theories. The requirement of calculability and natural smallness of neutrino mass leads to the following constraints: (i) left and right charged weak currents must be ''orthogonal'' to each other, and (ii) there should be no W/sub L/-W/sub R/ mixing at the three level. Finally, we exhibit a model in which, due to the existence of an unbroken symmetry of the total Lagrangian, the electron and muon neutrinos remain massless to all orders in perturbation theory

  13. The Baikal Neutrino Telescope

    International Nuclear Information System (INIS)

    Aynutdinov, V. M.; Balkanov, V. A.; Belolaptikov, I. A.; Bezrukov, L. B.; Borschev, D. A.; Budnev, N. M.; Burmistrov, K. V.; Danilchenko, I. A.; Davidov, Ya. I.; Domogatsky, G. V.; Doroshenko, A. A.; Dyachok, A. N.; Dzhilkibaev, Zh.-A. M.; Fialkovsky, S. V.; Gaponenko, O. N.; Golubkov, K. V.; Gress, O. A.; Gress, T. I.; Grishin, O. V.; Klabukov, A. M.

    2006-01-01

    We review the present status of the Baikal Neutrino Experiment and present results of a search for upward-going atmospheric neutrinos and magnetic monopoles obtained with the detector NT200. The results of a search for very high energy neutrinos are presented and an upper limit on the extraterrestrial diffuse neutrino flux is obtained. We describe the strategy of upgrading the NT200 to NT200+ and creating a detector on the Gigaton scale at Lake Baikal. The first results obtained with the new NT200+ detector as a basic cell of a future Gigaton detector are presented

  14. Solar neutrino experiments

    Energy Technology Data Exchange (ETDEWEB)

    Hampel, W [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany)

    1996-11-01

    The present status of experimental solar neutrino research is reviewed. Updated results from the Homestake, Kamiokande, GALLEX and SAGE detectors all show a deficit when compared to recent standard solar model calculations. Two of these detectors, GALLEX and SAGE, have recently been checked with artificial {sup 51}Cr neutrino sources. It is shown that astrophysical scenarios to solve the solar neutrino problems are not favoured by the data. There is hope that the results of forthcoming solar neutrino experiments can provide the answers to the open questions. (author) 6 figs., 3 tabs., 36 refs.

  15. Decays of supernova neutrinos

    International Nuclear Information System (INIS)

    Lindner, Manfred; Ohlsson, Tommy; Winter, Walter

    2002-01-01

    Supernova neutrinos could be well-suited for probing neutrino decay, since decay may be observed even for very small decay rates or coupling constants. We will introduce an effective operator framework for the combined description of neutrino decay and neutrino oscillations for supernova neutrinos, which can especially take into account two properties: one is the radially symmetric neutrino flux, allowing a decay product to be re-directed towards the observer even if the parent neutrino had a different original direction of propagation. The other is decoherence because of the long baselines for coherently produced neutrinos. We will demonstrate how to use this effective theory to calculate the time-dependent fluxes at the detector. In addition, we will show the implications of a Majoron-like decay model. As a result, we will demonstrate that for certain parameter values one may observe some effects which could also mimic signals similar to the ones expected from supernova models, making it in general harder to separate neutrino and supernova properties

  16. Neutrino-induced nucleosynthesis in core-collapse supernovae

    International Nuclear Information System (INIS)

    Hartmann, D.H.; Haxton, W.C.; Hoffman, R.D.; Woosley, S.E.; California Univ., Santa Cruz, CA

    1990-01-01

    Almost all of the 3·10 53 ergs liberated in a core collapse supernova is radiated as neutrinos by the cooling neutron star. The neutrinos can excite nuclei in the mantle of the star by their neutral and charged current reactions. The resulting spallation reactions are an important nuleosynthesis mechanism that may be responsible for the galactic abundances of 7 Li, 11 B, 19 F, 138 La, 180 Ta, and number of other nuclei. 10 refs., 1 fig., 1 tab

  17. Light sterile neutrino sensitivity at the nuSTORM facility

    Energy Technology Data Exchange (ETDEWEB)

    Adey, D.; Agarwalla, S. K.; Ankenbrandt, C. M.; Asfandiyarov, R.; Back, J. J.; Barker, G.; Baussan, E.; Bayes, R.; Bhadra, S.; Blackmore, V.; Blondel, A.; Bogacz, S. A.; Booth, C.; Boyd, S. B.; Bramsiepe, S. G.; Bravar, A.; Brice, S. J.; Bross, A. D.; Cadoux, F.; Cease, H.; Cervera, A.; Cobb, J.; Colling, D.; Coloma, P.; Coney, L.; Dobbs, A.; Dobson, J.; Donini, A.; Dornan, P.; Dracos, M.; Dufour, F.; Edgecock, R.; Geelhoed, M.; Uchida, M. A.; Ghosh, T.; Gómez-Cadenas, J. J.; de Gouvêa, A.; Haesler, A.; Hanson, G.; Harrison, P. F.; Hartz, M.; Hernández, P.; Hernando Morata, J. A.; Hodgson, P.; Huber, P.; Izmaylov, A.; Karadzhov, Y.; Kobilarcik, T.; Kopp, J.; Kormos, L.; Korzenev, A.; Kuno, Y.; Kurup, A.; Kyberd, P.; Lagrange, J. B.; Laing, A.; Liu, A.; Link, J. M.; Long, K.; Mahn, K.; Mariani, C.; Martin, C.; Martin, J.; McCauley, N.; McDonald, K. T.; Mena, O.; Mishra, S. R.; Mokhov, N.; Morfín, J.; Mori, Y.; Murray, W.; Neuffer, D.; Nichol, R.; Noah, E.; Palmer, M. A.; Parke, S.; Pascoli, S.; Pasternak, J.; Plunkett, R.; Popovic, M.; Ratoff, P.; Ravonel, M.; Rayner, M.; Ricciardi, S.; Rogers, C.; Rubinov, P.; Santos, E.; Sato, A.; Sen, T.; Scantamburlo, E.; Sedgbeer, J. K.; Smith, D. R.; Smith, P. J.; Sobczyk, J. T.; Søby, L.; Soler, F. J. P.; Sorel, M.; Snopok, P.; Stamoulis, P.; Stanco, L.; Striganov, S.; Tanaka, H. A.; Taylor, I. J.; Touramanis, C.; Tunnell, C. D.; Uchida, Y.; Vassilopoulos, N.; Wascko, M. O.; Weber, A.; Wilking, M. J.; Wildner, E.; Winter, W.

    2014-04-01

    A facility that can deliver beams of electron and muon neutrinos from the decay of a stored muon beam has the potential to unambiguously resolve the issue of the evidence for light sterile neutrinos that arises in short-baseline neutrino oscillation experiments and from estimates of the effective number of neutrino flavors from fits to cosmological data. In this paper, we show that the nuSTORM facility, with stored muons of 3.8GeV/c±10%, will be able to carry out a conclusive muon neutrino appearance search for sterile neutrinos and test the LSND and MiniBooNE experimental signals with 10σ sensitivity, even assuming conservative estimates for the systematic uncertainties. This experiment would add greatly to our knowledge of the contribution of light sterile neutrinos to the number of effective neutrino flavors from the abundance of primordial helium production and from constraints on neutrino energy density from the cosmic microwave background. The appearance search is complemented by a simultaneous muon neutrino disappearance analysis that will facilitate tests of various sterile neutrino models.

  18. SCRMS: An RFID and Sensor Web-Enabled Smart Cultural Relics Management System.

    Science.gov (United States)

    Xiao, Changjiang; Chen, Nengcheng; Li, Dandan; Lv, You; Gong, Jianya

    2016-12-30

    Cultural relics represent national or even global resources of inestimable value. How to efficiently manage and preserve these cultural relics is a vitally important issue. To achieve this goal, this study proposed, designed, and implemented an RFID and Sensor Web-enabled smart cultural relics management system (SCRMS). In this system, active photovoltaic subtle energy-powered Radio Frequency Identification (RFID) is used for long-range contactless identification and lifecycle management of cultural relics during their storage and circulation. In addition, different types of ambient sensors are integrated with the RFID tags and deployed around cultural relics to monitor their environmental parameters, helping to ensure that they remain in good condition. An Android-based smart mobile application, as middleware, is used in collaboration with RFID readers to collect information and provide convenient management for the circulation of cultural relics. Moreover, multiple sensing techniques are taken advantage of simultaneously for preservation of cultural relics. The proposed system was successfully applied to a museum in the Yongding District, Fujian Province, China, demonstrating its feasibility and advantages for smart and efficient management and preservation of cultural relics.

  19. SCRMS: An RFID and Sensor Web-Enabled Smart Cultural Relics Management System

    Directory of Open Access Journals (Sweden)

    Changjiang Xiao

    2016-12-01

    Full Text Available Cultural relics represent national or even global resources of inestimable value. How to efficiently manage and preserve these cultural relics is a vitally important issue. To achieve this goal, this study proposed, designed, and implemented an RFID and Sensor Web–enabled smart cultural relics management system (SCRMS. In this system, active photovoltaic subtle energy-powered Radio Frequency Identification (RFID is used for long-range contactless identification and lifecycle management of cultural relics during their storage and circulation. In addition, different types of ambient sensors are integrated with the RFID tags and deployed around cultural relics to monitor their environmental parameters, helping to ensure that they remain in good condition. An Android-based smart mobile application, as middleware, is used in collaboration with RFID readers to collect information and provide convenient management for the circulation of cultural relics. Moreover, multiple sensing techniques are taken advantage of simultaneously for preservation of cultural relics. The proposed system was successfully applied to a museum in the Yongding District, Fujian Province, China, demonstrating its feasibility and advantages for smart and efficient management and preservation of cultural relics.

  20. Explosive nucleosynthesis in a neutrino-driven core collapse supernova

    International Nuclear Information System (INIS)

    Fujimoto, Shin-ichiro; Kotake, Kei; Hashimoto, Masa-aki; Ono, Masaomi; Ohnishi, Naofumi

    2010-01-01

    We investigate explosive nucleosynthesis in a delayed neutrino-driven, supernova explosion aided by standing accretion shock instability (SASI), based on two-dimensional hydrodynamic simulations of the explosion of a 15 M · star. We take into accounts neutrino heating and cooling as well as change in electron fraction due to weak interactions appropriately, in the two-dimensional simulations. We assume the isotropic emission of neutrinos from the neutrino spheres with given luminosities. and the Fermi-Dirac distribution of given temperatures. We find that the stalled shock revives due to the neutrino heating aided by SASI for cases with L νe ≥3.9x10 52 ergss -1 and the as-pherical shock passes through the outer layers of the star (≥10,000 km), with the explosion energies of ∼10 51 ergs.Next we examine abundances and masses of the supernova ejecta. We find that masses of the ejecta and 56 Ni correlate with the neutrino luminosity, and 56 Ni mass is comparable to that observed in SN 1987A. We also find that abundance pattern of the supernova ejecta is similar to that of the solar system, for cases with high explosion energies of >10 51 ergs. We emphasize that 64 Zn, which is underproduced in the spherical case, is abundantly produced in slightly neutron-rich ejecta.

  1. Accelerator studies of neutrino oscillations

    CERN Document Server

    Ereditato, A

    2000-01-01

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

  2. Twin radio relics in the nearby low-mass galaxy cluster Abell 168

    Science.gov (United States)

    Dwarakanath, K. S.; Parekh, V.; Kale, R.; George, L. T.

    2018-06-01

    We report the discovery of twin radio relics in the outskirts of the low-mass merging galaxy cluster Abell 168 (redshift=0.045). One of the relics is elongated with a linear extent ˜800 kpc and projected width of ˜80 kpc and is located ˜900 kpc towards the north of the cluster centre, oriented roughly perpendicular to the major axis of the X-ray emission. The second relic is ring-shaped with a size ˜220 kpc and is located near the inner edge of the elongated relic at a distance of ˜600 kpc from the cluster centre. These radio sources were imaged at 323 and 608 MHz with the Giant Meterwave Radio Telescope and at 1520 MHz with the Karl G. Jansky Very Large Array (VLA). The elongated relic was detected at all frequencies, with a radio power of 1.38 ± 0.14 × 1023 W Hz-1 at 1.4 GHz and a power law in the frequency range 70-1500 MHz (S ∝ να, α = -1.1 ± 0.04). This radio power is in good agreement with that expected from the known empirical relation between the radio powers of relics and host cluster masses. This is the lowest mass (M500 = 1.24 × 1014 M⊙) cluster in which relics due to merger shocks are detected. The ring-shaped relic has a steeper spectral index (α) of -1.74 ± 0.29 in the frequency range 100-600 MHz. We propose this relic to be an old plasma, revived due to adiabatic compression by the outgoing shock that produced the elongated relic.

  3. Measurements of neutrino mass

    International Nuclear Information System (INIS)

    Robertson, R.G.H.

    1985-01-01

    Direct experimental information of neutrino mass as derived from the study of nuclear and elementary-particle weak decays is reviewed. Topics include tritium beta decay; the 3 He-T mass difference; electron capture decay of 163 Ho and 158 Tb; and limits on massive neutrinos from cosmology. 38 references

  4. Wroclaw neutrino event generator

    International Nuclear Information System (INIS)

    Nowak, J A

    2006-01-01

    A neutrino event generator developed by the Wroclaw Neutrino Group is described. The physical models included in the generator are discussed and illustrated with the results of simulations. The considered processes are quasi-elastic scattering and pion production modelled by combining the Δ resonance excitation and deep inelastic scattering

  5. Neutrino bounds from leptogenesis

    International Nuclear Information System (INIS)

    Hambye, T.

    2005-01-01

    Through leptogenesis, baryogenesis could have the same origin as neutrino masses. Emphasis is put on the conditions which, in order that this mechanism works, need to be fulfilled by the neutrino masses as well as by the heavy state masses. The model dependence of these conditions is discussed

  6. Neutrino flavor entanglement

    Energy Technology Data Exchange (ETDEWEB)

    Blasone, Massimo [Dipartimento di Fisica, Università degli Studi di Salerno, Via Ponte don Melillo, I-84084 Fisciano (Italy); INFN Sezione di Napoli, Gruppo collegato di Salerno (Italy); Dell' Anno, Fabio; De Siena, Silvio; Illuminati, Fabrizio [Dipartimento di Ingegneria Industriale, Università degli Studi di Salerno, Via Ponte don Melillo, I-84084 Fisciano (Italy)

    2013-04-15

    Neutrino oscillations can be equivalently described in terms of (dynamical) entanglement of neutrino flavor modes. We review previous results derived in the context of quantum mechanics and extend them to the quantum field theory framework, were a rich structure of quantum correlations appears.

  7. Neutrino flavor entanglement

    International Nuclear Information System (INIS)

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

    2013-01-01

    Neutrino oscillations can be equivalently described in terms of (dynamical) entanglement of neutrino flavor modes. We review previous results derived in the context of quantum mechanics and extend them to the quantum field theory framework, were a rich structure of quantum correlations appears

  8. Neutrinos (3/3)

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    In this course, the basic features of neutrino physics are reviewed, pointing to the very special characteristics of this elusive particle and to the related open questions. Emphasis is given to the neutrino oscillation mechanism and to the state of the art of the experimental studies, mostly in relation to the many interesting results obtained in the last years.

  9. Neutrinos (2/3)

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    In this course, the basic features of neutrino physics are reviewed, pointing to the very special characteristics of this elusive particle and to the related open questions. Emphasis is given to the neutrino oscillation mechanism and to the state of the art of the experimental studies, mostly in relation to the many interesting results obtained in the last years.

  10. Neutrinos (1/3)

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    In this course, the basic features of neutrino physics are reviewed, pointing to the very special characteristics of this elusive particle and to the related open questions. Emphasis is given to the neutrino oscillation mechanism and to the state of the art of the experimental studies, mostly in relation to the many interesting results obtained in the last years.

  11. Experimental Neutrino Physics

    Energy Technology Data Exchange (ETDEWEB)

    Wilkes, Richard Jeffrey [Univ. of Washington, Seattle, WA (United States)

    2017-11-15

    The University of Washington (UW) HEP neutrino group performed experimental research on the physics of neutrinos, using the capabilities offered by the T2K Experiment and the Super-Kamiokande Neutrino Observatory. The UW group included senior investigator R. J. Wilkes, two PhD students, four MS degree students, and a research engineer, all of whom are members of the international scientific collaborations for T2K and Super-Kamiokande. During the period of support, within T2K we pursued new precision studies sensitive to new physics, going beyond the limits of current measurements of the fundamental neutrino oscillation parameters (mass differences and mixing angles). We began efforts to measure (or significantly determine the absence of) 1 the CP-violating phase parameter δCP and determine the neutrino mass hierarchy. Using the Super-Kamiokande (SK) detector we pursued newly increased precision in measurement of neutrino oscillation parameters with atmospheric neutrinos, and extended the current reach in searches for proton decay, in addition to running the most sensitive supernova watch instrument [Scholberg 2012], performing other astrophysical neutrino studies, and analyzing beam-induced events from T2K. Overall, the research addressed central questions in the field of particle physics. It included the training of graduate students (both PhD and professional MS degree students), and postdoctoral researchers. Undergraduate students also participated as laboratory assistants.

  12. The solar neutrino problem

    International Nuclear Information System (INIS)

    Roxburgh, I.W.

    1981-01-01

    The problems posed by the low flux of neutrinos from the sun detected by Davis and coworkers are reviewed. Several proposals have been advanced to resolve these problems and the more reasonable (in the author's opinion) are presented. Recent claims that the neutrino may have finite mass are also considered. (orig.)

  13. Atmospheric neutrino fluxes

    International Nuclear Information System (INIS)

    Perkins, D.H.

    1984-01-01

    The atmospheric neutrino fluxes, which are responsible for the main background in proton decay experiments, have been calculated by two independent methods. There are discrepancies between the two sets of results regarding latitude effects and up-down asymmetries, especially for neutrino energies Esub(ν) < 1 GeV. (author)

  14. Perturbed S3 neutrinos

    DEFF Research Database (Denmark)

    jora, Renata; Schechter, Joseph; Naeem Shahid, M.

    2009-01-01

    We study the effects of the perturbation which violates the permutation symmetry of three Majorana neutrinos but preserves the well known (23) interchange symmetry. This is done in the presenceof an arbitrary Majorana phase which serves to insure the degeneracy of the three neutrinos at the unper...... at the unperturbed level....

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

    International Nuclear Information System (INIS)

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

    2000-01-01

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

  16. Neutrino nucleosynthesis in supernovae: Shell model predictions

    International Nuclear Information System (INIS)

    Haxton, W.C.

    1989-01-01

    Almost all of the 3 · 10 53 ergs liberated in a core collapse supernova is radiated as neutrinos by the cooling neutron star. I will argue that these neutrinos interact with nuclei in the ejected shells of the supernovae to produce new elements. It appears that this nucleosynthesis mechanism is responsible for the galactic abundances of 7 Li, 11 B, 19 F, 138 La, and 180 Ta, and contributes significantly to the abundances of about 15 other light nuclei. I discuss shell model predictions for the charged and neutral current allowed and first-forbidden responses of the parent nuclei, as well as the spallation processes that produce the new elements. 18 refs., 1 fig., 1 tab

  17. Physics of neutrino flavor transformation through matter-neutrino resonances

    Science.gov (United States)

    Wu, Meng-Ru; Duan, Huaiyu; Qian, Yong-Zhong

    2016-01-01

    In astrophysical environments such as core-collapse supernovae and neutron star-neutron star or neutron star-black hole mergers where dense neutrino media are present, matter-neutrino resonances (MNRs) can occur when the neutrino propagation potentials due to neutrino-electron and neutrino-neutrino forward scattering nearly cancel each other. We show that neutrino flavor transformation through MNRs can be explained by multiple adiabatic solutions similar to the Mikheyev-Smirnov-Wolfenstein mechanism. We find that for the normal neutrino mass hierarchy, neutrino flavor evolution through MNRs can be sensitive to the shape of neutrino spectra and the adiabaticity of the system, but such sensitivity is absent for the inverted hierarchy.

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

    International Nuclear Information System (INIS)

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

    2009-01-01

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

  19. The solar neutrino problem

    International Nuclear Information System (INIS)

    Zatsepin, G.

    1982-01-01

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

  20. Neutrino masses and mixing

    International Nuclear Information System (INIS)

    Fogli, G.

    1998-01-01

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

  1. Abundances in galaxies

    International Nuclear Information System (INIS)

    Pagel, B.E.J.

    1991-01-01

    Standard (or mildly inhomogeneous) Big Bang nucleosynthesis theory is well confirmed by abundance measurements of light elements up to 7 Li and the resulting upper limit to the number of neutrino families confirmed in accelerator experiments. Extreme inhomogeneous models with a closure density in form of baryons seem to be ruled out and there is no evidence for a cosmic 'floor' to 9 Be or heavier elements predicted in some versions of those models. Galaxies show a correlation between luminous mass and abundance of carbon and heavier elements, usually attributed to escape of hot gas from shallow potential wells. Uncertainties include the role of dark matter and biparametric behaviour of ellipticals. Spirals have radial gradients which may arise from a variety of causes. In our own Galaxy one can distinguish three stellar populations - disk, halo and bulge - characterised by differing metallicity distribution functions. Differential abundance effects are found among different elements in stars as a function of metallicity and presumably age, notably in the ratio of oxygen and α-particle elements to iron. These may eventually be exploitable to set a time scale for the formation of the halo, bulge and disk. (orig.)

  2. Molecular relics from chemical evolution and the origin of life

    International Nuclear Information System (INIS)

    Chela Flores, J.

    1994-04-01

    The main hypothesis proposed in this work intends to remove the difficulty that arises from the conjecture that the RNA world may have left molecular relics that may still be extant in the angiosperms. We discuss whether it is possible to envisage a possible evolutionary pathway of the RNA replicators spanning the vast time span separating the first appearance of the angiosperms, late in the Mesozoic era (the Lower Cretaceous), from the most likely suberas in which the RNA world may have occurred, namely the Hadean/Early Archean. In order to address this question we suggest that through horizontal gene transfer, as well as through a series of symbiosis of the precursor cell of the land plants, the genes of the replicases (RNA-directed RNA polymerases) associated with putative DNA-independent RNA replicators may have been transferred vertically, eventually becoming specific to the angiosperms. (author). Refs, 7 tabs

  3. Nuclear weak interactions, supernova nucleosynthesis and neutrino oscillation

    Science.gov (United States)

    Kajino, Toshitaka

    2013-07-01

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

  4. Hardron production and neutrino beams

    Science.gov (United States)

    Guglielmi, A.

    2006-11-01

    The precise measurements of the neutrino mixing parameters in the oscillation experiments at accelerators require new high-intensity and high-purity neutrino beams. Ancillary hadron-production measurements are then needed as inputs to precise calculation of neutrino beams and of atmospheric neutrino fluxes.

  5. Sudbury neutrino observatory

    International Nuclear Information System (INIS)

    Ewan, G.T.; Mak, H.B.; Robertson, B.C.

    1985-07-01

    This report discusses the proposal to construct a unique neutrino observatory. The observatory would contain a Cerenkov detector which would be located 2070 m below the earth's surface in an INCO mine at Creighton near Sudbury and would contain 1000 tons of D20 which is an excellent target material. Neutrinos carry detailed information in their spectra on the reactions taking place deep in the interstellar interior and also provide information on supernova explosions. In addition to their role as astrophysical probes a knowledge of the properties of neutrinos is crucial to theories of grand unification. There are three main objectives of the laboratory. The prime objective will be to study B electron neutrinos from the sun by a direct counting method that will measure their energy and direction. The second major objective will be to establish if electron neutrinos change into other neutrino species in transit from the sun to the earth. Finally it is hoped to be able to observe a supernova with the proposed detector. The features of the Sudbury Neutrino Observatory which make it unique are its high sensitivity to electron neutrinos and its ability to detect all other types of neutrinos of energy greater than 2.2 MeV. In section II of this proposal the major physics objectives are discussed in greater detail. A conceptual design for the detector, and measurements and calculations which establish the feasibility of the neutrino experiments are presented in section III. Section IV is comprised of a discussion on the possible location of the laboratory and Section V contains a brief indication of the main areas to be studied in Phase II of the design study

  6. The Sudbury neutrino observatory

    International Nuclear Information System (INIS)

    McLatchie, W.; Earle, E.D.

    1987-08-01

    This report initially discusses the Homestake Mine Experiment, South Dakota, U.S.A. which has been detecting neutrinos in 38 x 10 litre vats of cleaning fluid containing chlorine since the 1960's. The interation between neutrinos and chlorine produces argon so the number of neutrinos over time can be calculated. However, the number of neutrinos which have been detected represent only one third to one quarter of the expected number i.e. 11 per month rather than 48. It is postulated that the electron-neutrinos originating in the solar core could change into muon- or tau-neutrinos during passage through the high electron densities of the sun. The 'low' results at Homestake could thus be explained by the fact that the experiment is only sensitive to electron-neutrinos. The construction of a heavy water detector is therefore proposed as it would be able to determine the energy of the neutrinos, their time of arrival at the detector and their direction. It is proposed to build the detector at Creighton mine near Sudbury at a depth of 6800 feet below ground level thus shielding the detector from cosmic rays which would completely obscure the neutrino signals from the detector. The report then discusses the facility itself, the budget estimate and the social and economic impact on the surrounding area. At the time of publication the proposal for the Sudbury Neutrino Observatory was due to be submitted for peer review by Oct. 1, 1987 and then to various granting bodies charged with the funding of scientific research in Canada, the U.S.A. and Britain

  7. Relic density and CMB constraints on dark matter annihilation with Sommerfeld enhancement

    International Nuclear Information System (INIS)

    Zavala, Jesus; White, Simon D. M.; Vogelsberger, Mark

    2010-01-01

    We calculate how the relic density of dark matter particles is altered when their annihilation is enhanced by the Sommerfeld mechanism due to a Yukawa interaction between the annihilating particles. Maintaining a dark matter abundance consistent with current observational bounds requires the normalization of the s-wave annihilation cross section to be decreased compared to a model without enhancement. The level of suppression depends on the specific parameters of the particle model, with the kinetic decoupling temperature having the most effect. We find that the cross section can be reduced by as much as an order of magnitude for extreme cases. We also compute the μ-type distortion of the CMB energy spectrum caused by energy injection from such Sommerfeld-enhanced annihilation. Our results indicate that in the vicinity of resonances, associated with bound states, distortions can be large enough to be excluded by the upper limit |μ|≤9.0x10 -5 found by the FIRAS (Far Infrared Absolute Spectrophotometer) instrument on the COBE (Cosmic Background Explorer) satellite.

  8. The physics of massive neutrinos

    CERN Document Server

    Kayser, Boris; Perrier, Frederic

    1989-01-01

    This book explains the physics and phenomenology of massive neutrinos. The authors argue that neutrino mass is not unlikely and consider briefly the search for evidence of this mass in decay processes before they examine the physics and phenomenology of neutrino oscillation. The physics of Majorana neutrinos (neutrinos which are their own antiparticles) is then discussed. This volume requires of the reader only a knowledge of quantum mechanics and of very elementary quantum field theory.

  9. Status of Heavy Neutrino Experiments

    CERN Document Server

    Wynne, Benjamin; The ATLAS collaboration

    2017-01-01

    The observation of neutrino oscillations raises the possibility that there exist additional, undiscovered high-mass neutrinos, giving mass to Standard Model neutrinos via the seesaw mechanism. By pushing the collider energy frontier at the LHC, the possibility arises that these heavy neutrinos may be produced and identified. We summarise the latest LHC results of searches for heavy neutrinos in a variety of final states.

  10. Lepton flavor violation and scalar dark matter in a radiative model of neutrino masses

    Energy Technology Data Exchange (ETDEWEB)

    Esch, Sonja; Klasen, Michael; Lamprea, David R. [Westfaelische Wilhelms-Universitaet Muenster, Institut fuer Theoretische Physik, Muenster (Germany); Yaguna, Carlos E. [Universidad Pedagogica y Tecnologica de Colombia, Escuela de Fisica, Tunja (Colombia)

    2018-02-15

    We consider a simple extension of the Standard Model that can account for the dark matter and explain the existence of neutrino masses. The model includes a vector-like doublet of SU(2), a singlet fermion, and two scalar singlets, all of them odd under a new Z{sub 2} symmetry. Neutrino masses are generated radiatively by one-loop processes involving the new fields, while the dark matter candidate is the lightest neutral particle among them. We focus specifically on the case where the dark matter particle is one of the scalars and its relic density is determined by its Yukawa interactions. The phenomenology of this setup, including neutrino masses, dark matter and lepton flavor violation, is analyzed in some detail. We find that the dark matter mass must be below 600 GeV to satisfy the relic density constraint. Lepton flavor violating processes are shown to provide the most promising way to test this scenario. Future μ → 3e and μ-e conversion experiments, in particular, have the potential to probe the entire viable parameter space of this model. (orig.)

  11. Neutrinos at CERN

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    CERN's long and distinguished neutrino tradition began in 1958 at the then new 500 MeV synchrocyclotron (SC) with the first observation of the decay of a charged pion into an electron and a neutrino. At that time, the first ideas on the special (vector/axial vector) structure of the weak interactions had been put forward by Feynman and Gell-Mann and by Marshak and Sudarshan, but the continual non-observation of that charged pion decay was holding up progress. This decay is only one part in ten thousand, and is masked by the dominant muon-neutrino channel. A special telescope was built to pick up the high energy electrons from the pion decay. In 1962 came another SC neutrino success, with the first measurement of the decay of a charged pion into a neutral one, with emission of an electron and a neutrino. Meanwhile the main thrust of CERN's neutrino effort was taking shape at the PS. By the close of 1960, CERN had decided to attack neutrino physics using several detectors - a 1m heavy liquid bubble chamber from Andre Lagarrigue's team in Paris, a CERN 1 m heavy liquid bubble chamber, and a hybrid chamber/counter from a group led by Helmut Faissner

  12. Neutrino Oscillations Physics

    Science.gov (United States)

    Fogli, Gianluigi

    2005-06-01

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

  13. Monochromatic neutrino beams

    International Nuclear Information System (INIS)

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

    2005-01-01

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

  14. Another shock for the Bullet cluster, and the source of seed electrons for radio relics

    Science.gov (United States)

    Shimwell, Timothy W.; Markevitch, Maxim; Brown, Shea; Feretti, Luigina; Gaensler, B. M.; Johnston-Hollitt, M.; Lage, Craig; Srinivasan, Raghav

    2015-05-01

    With Australia Telescope Compact Array observations, we detect a highly elongated Mpc-scale diffuse radio source on the eastern periphery of the Bullet cluster 1E 0657-55.8, which we argue has the positional, spectral and polarimetric characteristics of a radio relic. This powerful relic (2.3 ± 0.1 × 1025 W Hz-1) consists of a bright northern bulb and a faint linear tail. The bulb emits 94 per cent of the observed radio flux and has the highest surface brightness of any known relic. Exactly coincident with the linear tail, we find a sharp X-ray surface brightness edge in the deep Chandra image of the cluster - a signature of a shock front in the hot intracluster medium (ICM), located on the opposite side of the cluster to the famous bow shock. This new example of an X-ray shock coincident with a relic further supports the hypothesis that shocks in the outer regions of clusters can form relics via diffusive shock (re-)acceleration. Intriguingly, our new relic suggests that seed electrons for reacceleration are coming from a local remnant of a radio galaxy, which we are lucky to catch before its complete disruption. If this scenario, in which a relic forms when a shock crosses a well-defined region of the ICM polluted with aged relativistic plasma - as opposed to the usual assumption that seeds are uniformly mixed in the ICM - is also the case for other relics, this may explain a number of peculiar properties of peripheral relics.

  15. Sudbury neutrino observatory

    International Nuclear Information System (INIS)

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

    1986-10-01

    This report is a supplement to a report (SNO-85-3 (Sudbury Neutrino Observatory)) which contained the results of a feasibility study on the construction of a deep underground neutrino observatory based on a 1000 ton heavy water Cerenkov detector. Neutrinos carry detailed information in their spectra on the reactions taking place deep in the interstellar interior and also provide information on supernova explosions. In addition to their role as astrophysical probes, a knowledge of the properties of neutrinos is crucial to theories of grand unification. The Sudbury Neutrino Observatory is unique in its high sensitivity to electron neutrinos and its ability to detect all other types of neutrinos of energy greater than 2.2 MeV. The results of the July 1985 study indicated that the project is technically feasible in that the proposed detector can measure the direction and energy of electron neutrinos above 7 MeV and the scientific programs will make significant contributions to physics and astrophysics. This present report contains new information obtained since the 1985 feasibility study. The enhanced conversion of neutrinos in the sun and the new physics that could be learned using the heavy water detector are discussed in the physics section. The other sections will discuss progress in the areas of practical importance in achieving the physics objectives such as new techniques to measure, monitor and remove low levels of radioactivity in detector components, ideas on calibration of the detector and so forth. The section entitled Administration contains a membership list of the working groups within the SNO collaboration

  16. CONFERENCE: Neutrino mass

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    The successes in capturing neutrinos from last year's supernova underlined the usefulness of large underground detectors for this sort of physics, and ambitious new projects are now in the pipeline. Meanwhile another approach to cosmic neutrino detection, carefully prepared during the past decade, has now taken its first experimental steps. DUMAND - Deep Underwater Muon and Neutrino Detector - aims to use the ocean as the active medium, tracking particles with arrays of photomultipliers picking up the tiny nanosecond flashes of blue Cherenkov light emitted by cosmic particles as they pass through seawater

  17. CONFERENCE: Neutrino mass

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1988-06-15

    The successes in capturing neutrinos from last year's supernova underlined the usefulness of large underground detectors for this sort of physics, and ambitious new projects are now in the pipeline. Meanwhile another approach to cosmic neutrino detection, carefully prepared during the past decade, has now taken its first experimental steps. DUMAND - Deep Underwater Muon and Neutrino Detector - aims to use the ocean as the active medium, tracking particles with arrays of photomultipliers picking up the tiny nanosecond flashes of blue Cherenkov light emitted by cosmic particles as they pass through seawater.

  18. Results from neutrino experiments

    International Nuclear Information System (INIS)

    Smirnov, A.Yu.

    1993-11-01

    Recent (first or/and the best) results from the neutrino experiments are reviewed and their implications for the theory are discussed. The sense of the experiments is the searching for neutrino masses, mixing and interactions beyond the standard model. Present laboratory experiments give upper bounds on the masses and the mixing which are at the level of predictions of the ''electroweak see-saw''. Positive indications of nonzero lepton mixing follow from studies of the solar and atmospheric neutrinos. (author). 95 refs, 11 figs

  19. Neutrino mass experiments

    International Nuclear Information System (INIS)

    Robertson, R.G.H.

    1989-01-01

    The current status of the experimental search for neutrino mass is reviewed, with emphasis on direct kinematic methods. Simpson and Hime report finding new evidence for a 17-keV neutrino in the β decay of 3 H and 35 S. The situation concerning the electron neutrino mass as measured in tritium beta decay has not changed significantly in the last two years. We discuss the ''model independent'' lower limit of 17 eV obtained by the ITEP group in light of existing data on the 3 H-- 3 He mass difference. 42 refs., 1 fig., 1 tab

  20. Testing for new physics: neutrinos and the primordial power spectrum

    Energy Technology Data Exchange (ETDEWEB)

    Canac, Nicolas; Abazajian, Kevork N. [Department of Physics, University of California at Irvine, Irvine, CA 92697 (United States); Aslanyan, Grigor [Berkeley Center for Cosmological Physics, University of California, Berkeley, CA 94720 (United States); Easther, Richard [Department of Physics, University of Auckland, Private Bag 92019, Auckland (New Zealand); Price, Layne C., E-mail: ncanac@uci.edu, E-mail: aslanyan@berkeley.edu, E-mail: kevork@uci.edu, E-mail: r.easther@auckland.ac.nz, E-mail: laynep@andrew.cmu.edu [McWilliams Center for Cosmology, Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213 (United States)

    2016-09-01

    We test the sensitivity of neutrino parameter constraints from combinations of CMB and LSS data sets to the assumed form of the primordial power spectrum (PPS) using Bayesian model selection. Significantly, none of the tested combinations, including recent high-precision local measurements of H{sub 0} and cluster abundances, indicate a signal for massive neutrinos or extra relativistic degrees of freedom. For PPS models with a large, but fixed number of degrees of freedom, neutrino parameter constraints do not change significantly if the location of any features in the PPS are allowed to vary, although neutrino constraints are more sensitive to PPS features if they are known a priori to exist at fixed intervals in log k . Although there is no support for a non-standard neutrino sector from constraints on both neutrino mass and relativistic energy density, we see surprisingly strong evidence for features in the PPS when it is constrained with data from Planck 2015, SZ cluster counts, and recent high-precision local measurements of H{sub 0}. Conversely combining Planck with matter power spectrum and BAO measurements yields a much weaker constraint. Given that this result is sensitive to the choice of data this tension between SZ cluster counts, Planck and H{sub 0} measurements is likely an indication of unmodeled systematic bias that mimics PPS features, rather than new physics in the PPS or neutrino sector.

  1. Discussion of impact of relics activation on protection and utilization approaches-take the old summer palace as an example

    Science.gov (United States)

    Xiaoqi, J.

    2015-08-01

    As the popularization of cultural relics and the rapid development of cultural tourism industry, a large number of cultural relic tourism resources goes into public eyes. Activation of relics has became an important way for tourist to contact and understand culture relics. The way of how to properly interpret the historical sense and cultural uniqueness to the masses of tourists in order to achieve social service functions of relic resources has always been research focal point of site protection and utilization, so nowadays it has important significance to protection and utilization of heritage resources in our country. From the point of activation of relics and based on the analysis of resource characteristic, the paper in depth discuss ways of activation of relics of the Old Summer Palace, in order to provide reference for sustainable development of sites tourism in China.

  2. Analysis on the environment of cultural relic as tourist attraction--take Yungang Grottoes as an example

    Science.gov (United States)

    Xiangdong, Zhu; Jie, Bai

    2018-03-01

    Cultural relic resources are precious non-renewable resources and an important cornerstone for the development of cultural relic tourism. With the rapid development of tourism industry, the native environment of cultural relics is being squeezed constantly. Meanwhile, under the economic interests, cultural relic’s protection and heritage tourism contradictions continue to intensify. The present era which the architectural style is convergence, cultural relics protection is simplistic, restore historical sites blindly and other. In the historical process of economic development and the acceleration of new-type urbanization, the heritage industry faces the dual tasks and development challenges. As cultural relic protection workers, investigation of the utilization of cultural relic’s tourist attractions, investigation and analysis of the Yungang Grottoes, indicating cultural relics as a tourist attraction, not only to strengthen the protection of ontology, also should attach importance to the coordinated development of the protection of cultural relics and the utilization of tourism.

  3. Neutrino physics present and future

    CERN Multimedia

    CERN. Geneva

    2006-01-01

    Our understanding of neutrinos has been revolutionized by the discovery that they have nonzero masses and very large mixing. We will explain the phenomenology of massive neutrinos, including neutrino oscillation in vacuum and in matter, and the physics of neutrinos that are their own antiparticles. We will review the evidence for neutrino masses and mixing, and summarize what has been learned about the neutrinos so far. Identifying the very interesting open questions raised by the discovery of neutrino mass, we will discuss how these questions may be answered through future experiments. Finally, we will consider the possibility that CP violation by neutrinos is the key to understanding the matter-antimatter asymmetry of the universe, and discuss the see-saw theory of why neutrino masses are so tiny.

  4. Mirror model for sterile neutrinos

    International Nuclear Information System (INIS)

    Berezinsky, Veniamin; Narayan, Mohan; Vissani, Francesco

    2003-01-01

    Sterile neutrinos are studied as subdominant contribution to solar neutrino physics. The mirror-matter neutrinos are considered as sterile neutrinos. We use the symmetric mirror model with gravitational communication between mirror and visible sectors. This communication term provides mixing between visible and mirror neutrinos with the basic scale μ=v EW 2 /M Pl =2.5x10 -6 eV, where v EW =174 GeV is the vacuum expectation value of the standard electroweak group and M Pl is the Planckian mass. It is demonstrated that each mass eigenstate of active neutrinos splits into two states separated by small Δm 2 . Unsuppressed oscillations between active and sterile neutrinos (ν a ↔ν s ) occur only in transitions between each of these close pairs ('windows'). These oscillations are characterized by very small Δm 2 and can suppress the flux and distort spectrum of pp-neutrinos in detectable way. The other observable effect is anomalous seasonal variation of neutrino flux, which appears in LMA solution. The considered subdominant neutrino oscillations ν a ↔ν s can reveal itself as big effects in observations of supernova neutrinos and high-energy (HE) neutrinos. In the case of HE neutrinos they can provide a very large diffuse flux of active neutrinos unconstrained by the e-m cascade upper limit

  5. A Virtual Reconstruction Methodology for Archaeological Heritage in East Asia – Practical Experience from the Re-relic Program in China

    Directory of Open Access Journals (Sweden)

    Yan He

    2013-11-01

    Full Text Available There is as much abundance of archaeological heritage in East Asia as there is diversity in the methodology for its reconstruction and representation. The Re-relic program in China recognizes the uniqueness of archaeological heritage in East Asia and has developed a tailored virtual reconstruction methodology that is both scientifically robust and popular for public interpretation. The theoretical consideration and field experience over the years shall contribute to the global understanding of the value and technique in virtual reconstruction, while testifying to the very principles of Seville Charter.

  6. Geo-Neutrinos

    International Nuclear Information System (INIS)

    Dye, S.T.

    2009-01-01

    This paper briefly reviews recent developments in the field of geo-neutrinos. It describes current and future detection projects, discusses modeling projects, suggests an observational program, and visits geo-reactor hypotheses.

  7. Geo-Neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Dye, S.T. [Department of Physics and Astronomy, University of Hawaii at Manoa, 2505 Correa Road, Honolulu, Hawaii, 96822 (United States); College of Natural Sciences, Hawaii Pacific University, 45-045 Kamehameha Highway, Kaneohe, Hawaii, 96744 (United States)

    2009-03-15

    This paper briefly reviews recent developments in the field of geo-neutrinos. It describes current and future detection projects, discusses modeling projects, suggests an observational program, and visits geo-reactor hypotheses.

  8. The World of Neutrinos

    Indian Academy of Sciences (India)

    4. Their detection ... He + light. +2νe. Neutrinos needed to conserve energy, momentum, angular momentum .... almost massless. (at least a million times lighter than electrons) only weak .... Signals of physics beyond the Standard Model.

  9. Results from atmospheric neutrinos

    Indian Academy of Sciences (India)

    Africa and South India first detected the natural neutrinos and observed .... lucky coincidences, such as the angular diameter of the moon and sun being ... (where there is some peaking due to longer flight paths for pions in the atmosphere).

  10. Neutrinos: ghosts of matter

    CERN Multimedia

    Wark, Dave

    2005-01-01

    The discovery that neutrinos have masse and can oscillate between different flavours was one of the major breakthroughts in particle physics in the past decade, but there is much about these mysterious particles that we still do not understand

  11. Neutrino mass: Recent results

    International Nuclear Information System (INIS)

    Robertson, R.G.H.

    1989-01-01

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

  12. Neutrino beam plasma instability

    Indian Academy of Sciences (India)

    positron or electron–proton plasma in the context of early universe, stars and supernova ... proper. Of course, in their later work on kinetic theory (KT) [5] of neutrino plasma inter- .... for electron also with additional electric potential term.

  13. Gravitational Waves and Neutrinos

    OpenAIRE

    Sturani, Riccardo

    2018-01-01

    We give an overview about the recent detection of gravitational waves by the Advanced LIGO first and second observing runs and by Advanced Virgo, with emphasis on the prospects for multi-messenger astronomy involving neutrinos detections.

  14. Perspectives in Neutrino Physics

    CERN Document Server

    Altarelli, Guido

    2011-01-01

    This is a Concluding Talk, not a Summary of the Conference. I will discuss some of the highlights that particularly impressed me (a subjective choice) and make some comments on the status and the prospects of neutrino mass and mixing.

  15. Neutrinos, on your marks...!

    CERN Multimedia

    2006-01-01

    As the Bulletin was about to be released, the CNGS team was ready to produce its first neutrinos. The gradual commissioning of the installation should result in the production of a nominal beam during the month of August.

  16. Introduction to neutrino physics

    International Nuclear Information System (INIS)

    Naumov, D.V.

    2011-01-01

    This is a manuscript of lectures presented by the author at the Baikal Summer School on Physics of Elementary Particles and Astrophysics 2010. The lectures are intended mainly for students and young researchers as an introductory course of neutrino physics

  17. External meeting: KATRIN - direct measurement of neutrino masses with sub-eV sensitivity

    CERN Multimedia

    2007-01-01

    GENEVA UNIVERSITY - ECOLE DE PHYSIQUE Département de physique nucléaire et corspusculaire 24, Quai Ernest-Ansermet 1211 GENEVE 4 - Tél : 022 379 62 73 - Fax: 022 379 69 92 Wednesday 18 April 2007 PARTICLE PHYSICS SEMINAR at 17:00 - Stückelberg Auditorium KATRIN - direct measurement of neutrino masses with sub-eV sensitivity by Prof. Guido Drexlin, Karlsruhe Institute of Technology KIT The major scientific objective of the international Karlsruhe Tritum Neutrino (KATRIN) Experiment is the model independent measurement of the electron neutrino mass in tritium beta decay with a sensitivity of 200 meV. In the cosmological context, this allows an investigation of whether massive relic neutrinos left over from the Big Bang play a specific role as hot dark matter in the evolution of large scale structures of the universe. In particle physics KATRIN will allow for discrimination between different neutrino mass models (either of quasi-degenerate or hierarchical pattern).The key components of KATRIN comprise...

  18. Effective Majorana neutrino decay

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, Lucia [Instituto de Fisica, Facultad de Ingenieria,Universidad de la Republica, Montevideo (Uruguay); Romero, Ismael; Peressutti, Javier; Sampayo, Oscar A. [Universidad Nacional de Mar del Plata, Departamento de Fisica, Instituto de Investigaciones Fisicas de Mar del Plata (IFIMAR) CONICET, UNMDP, Mar del Plata (Argentina)

    2016-08-15

    We study the decay of heavy sterile Majorana neutrinos according to the interactions obtained from an effective general theory. We describe the two- and three-body decays for a wide range of neutrino masses. The results obtained and presented in this work could be useful for the study of the production and detection of these particles in a variety of high energy physics experiments and astrophysical observations. We show in different figures the dominant branching ratios and the total decay width. (orig.)

  19. Neutrino physics and accelerators

    International Nuclear Information System (INIS)

    Kaftanov, V.

    1978-01-01

    The history is described of experiments aimed at the study of direct neutrino-matter interactions conducted in the past twenty years. Experiments are outlined carried out with the objective of proving the existence of the intermediate W meson which had been predicted by the weak interaction theory. The methods of obtaining neutrino beams using accelerators and the detectors used are briefly shown. Also described are experiments to be conducted in the near future in different laboratories. (Z.J.)

  20. Massive neutrinos in astrophysics

    International Nuclear Information System (INIS)

    Qadir, A.

    1982-08-01

    Massive neutrinos are among the big hopes of cosmologists. If they happen to have the right mass they can close the Universe, explain the motion of galaxies in clusters, provide galactic halos and even, possibly, explain galaxy formation. Tremaine and Gunn have argued that massive neutrinos cannot do all these things. I will explain, here, what some of us believe is wrong with their arguments. (author)

  1. Mass relation for neutrinos

    Science.gov (United States)

    Babu; Barr

    2000-08-07

    A generalization of the well-known Georgi-Jarlskog relation (m(&mgr;)/m(tau)) = 3(m(s)/m(b)) to neutrinos is found in the context of SO(10). This new relation is (m(nu(&mgr;))/m(nu(tau))) = 16(m(c)/m(t)), which is consistent with present data, assuming the Mikheyev-Smirnov-Wolfenstein solution to the solar neutrino problem.

  2. Radiative Majorana Neutrino Masses

    OpenAIRE

    Hou, Wei-Shu; Wong, Gwo-Guang

    1994-01-01

    We present new radiative mechanisms for generating Majorana neutrino masses, within an extension of the standard model that successfully generates radiative charged lepton masses, order by order, from heavy sequential leptons. Only the new sequential neutral lepton has a right-handed partner, and its Majorana mass provides the seed for Majorana neutrino mass generation. Saturating the cosmological bound of $50$ eV with $m_{\

  3. Mass Relation for Neutrinos

    International Nuclear Information System (INIS)

    Babu, K. S.; Barr, S. M.

    2000-01-01

    A generalization of the well-known Georgi-Jarlskog relation (m μ /m τ ) =3(m s /m b ) to neutrinos is found in the context of SO(10) . This new relation is (m ν μ /m ν τ )=16(m c /m t ) , which is consistent with present data, assuming the Mikheyev-Smirnov-Wolfenstein solution to the solar neutrino problem. (c) 2000 The American Physical Society

  4. Neutrinos: Heavy water detector

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    The proponents of the Sudbury Neutrino Observatory (SNO) received a welcome Christmas present when William Winegard, Canadian Minister for Science and Technology announced the final details of the funding for this project, totalling 48 million Canadian dollars and including contributions from the US and the UK. The SNO experiment will extend significantly the study of solar neutrinos, using some 1,000 tonnes of heavy water to be installed more than two kilometres below ground in a nickel mine at Sudbury, Ontario

  5. Features of neutrino mixing

    Science.gov (United States)

    Chiu, S. H.; Kuo, T. K.

    2018-03-01

    The elements (squared) of the neutrino mixing matrix are found to satisfy, as functions of the induced mass, a set of differential equations. They show clearly the dominance of pole terms when the neutrino masses "cross." Using the known vacuum mixing parameters as initial conditions, it is found that these equations have very good approximate solutions, for all values of the induced mass. The results are applicable to long baseline experiments.

  6. The solar neutrino problem

    International Nuclear Information System (INIS)

    Bahcall, J.N.

    1986-01-01

    The observed capture rate for solar neutrinos in the /sup 37/Cl detector is lower than the predicted capture rate. This discrepancy between theory and observation is known as the 'solar neutrino problem.' The author reviews the basic elements in this problem: the detector efficiency, the theory of stellar (solar) evolution, the nuclear physics of energy generation, and the uncertainties in the predictions. He also answers the questions of: So What? and What Next?

  7. An Account of Translation of Relics: the Writings of Alonso de Cartagena

    Directory of Open Access Journals (Sweden)

    Luis Fernández Gallardo

    2018-01-01

    Full Text Available The narratives of translation of relics is a genre of devotional literature that didn´t develop extensively in Medieval Castile. But Alonso de Cartagena contributed to it remarkably. In 1453, during a pastoral visit, he decided to move the relics of St. Juliana to a more honorable place. He wrote an account of these facts that adjusts strictly to the features of the genre. This vernacular text contains an exposition about the cult of saints and their relics, which has an intense Thomist inspiration: it sets theological questions with precision and clarity. The provisions on the decoration of the chapel of the relics offer an interesting testimony of the debate on religious image which is then developed in Castile.

  8. a Review of Digital Watermarking and Copyright Control Technology for Cultural Relics

    Science.gov (United States)

    Liu, H.; Hou, M.; Hu, Y.

    2018-04-01

    With the rapid growth of the application and sharing of the 3-D model data in the protection of cultural relics, the problem of Shared security and copyright control of the three-dimensional model of cultural relics is becoming increasingly prominent. Followed by a digital watermarking copyright control has become the frontier technology of 3-D model security protection of cultural relics and effective means, related technology research and application in recent years also got further development. 3-D model based on cultural relics digital watermarking and copyright control technology, introduces the research background and demand, its unique characteristics were described, and its development and application of the algorithm are discussed, and the prospects of the future development trend and some problems and the solution.

  9. “The Godly Greedy Appetite”: New Relic Circulation in the Early Modern World

    Directory of Open Access Journals (Sweden)

    Igor Pérez Tostado

    2017-05-01

    Full Text Available Having lost all monasteries and a good deal of its medieval Christian movable assets, England became one of the greatest producers of new Catholic relics during the sixteenth and seventeenth centuries. This article aims to look, from a material point of view, at the circulation and consumption of English relics on the Catholic continent. In this case, these products were created because of violence and circulated as an answer to it. Gifts and the exchange of relics served to obtain support for the exiled Catholics and for the institutions providing for their education created in the continent, and allowed them to participate in the necropolitics of the Spanish Monarchy. Relics, artifacts and printed and manuscript narratives brought back from all over the world helped construct a selfimage of an English Catholic as a necrocommunity imbued by a sense of historical continuity and connected to a global imagined community.

  10. Neutrino physics with DARWIN

    Science.gov (United States)

    Benabderrahmane, M. L.

    2017-09-01

    DARWIN (DARk matter WImp search with liquid xenoN) will be a multi-ton dark matter detector with the primary goal of exploring the entire experimentally accessible parameter space for weakly interacting massive particles (WIMPs) over a wide mass-range. With its 40 tonne active liquid xenon target, low-energy threshold and ultra-low background level, DARWIN can also search for other rare interactions. Here we present its sensitivity to low-energy solar neutrinos and to neutrinoless double beta decay. In a low-energy window of 2-30 keV a rate of 105/year, from pp and 7Be neutrinos can be reached. Such a measurement, with 1% precision will allow testing neutrinos models. DARWIN could also reach a competitive half-life sensitivity of 8.5 · 1027 y to the neutrinoless double beta decay (0νββ) of 136Xe after an exposure of 140 t×y of natural xenon. Nuclear recoils from coherent scattering of solar neutrinos will limit the sensitivity to WIMP masses below 5 GeV/c2, and the event rate from 8B neutrinos would range from a few to a few tens of events per tonne and year, depending on the energy threshold of the detector. Deviations from the predicted but yet unmeasured neutrino flux would be an indication for physics beyond the Standard Model

  11. The Sudbury Neutrino Observatory

    International Nuclear Information System (INIS)

    Norman, E.B.; Chan, Y.D.; Garcia, A.; Lesko, K.T.; Smith, A.R.; Stokstad, R.G.; Zlimen, I.; Evans, H.C.; Ewan, G.T.; Hallin, A.; Lee, H.W.; Leslie, J.R.; MacArthur, J.D.; Mak, H.B.; McDonald, A.B.; McLatchie, W.; Robertson, B.C.; Skensved, P.; Sur, B.; Jagam, P.; Law, J.; Ollerhead, R.W.; Simpson, J.J.; Wang, J.X.; Tanner, N.W.; Jelley, N.A.; Barton, J.C.; Doucas, G.; Hooper, E.W.; Knox, A.B.; Moorhead, M.E.; Omori, M.; Trent, P.T.; Wark, D.L.

    1992-11-01

    Two experiments now in progress have reported measurements of the flux of high energy neutrinos from the Sun. Since about 1970, Davis and his co-workers have been using a 37 Cl-based detector to measure the 7 Be and 8 B solar neutrino flux and have found it to be at least a factor of three lower than that predicted by the Standard Solar Model (SSM). The Kamiokande collaborations has been taking data since 1986 using a large light-water Cerenkov detector and have confirmed that the flux is about two times lower than predicted. Recent results from the SAGE and GALLEX gallium-based detectors show that there is also a deficit of the low energy pp solar neutrinos. These discrepancies between experiment and theory could arise because of inadequacies in the theoretical models of solar energy generation or because of previously unobserved properties of neutrinos. The Sudbury Neutrino Observatory (SNO) will provide the information necessary to decide which of these solutions to the ''solar neutrino problem'' is correct

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

    International Nuclear Information System (INIS)

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

    1987-01-01

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

  13. Neutrino confinement in collapsing stellar cores

    International Nuclear Information System (INIS)

    Chung, K.C.

    1987-01-01

    Neutrino confinement is expected to occur in the core of highly evolved stars, leading to the formation of a degenerate neutrino gas. The main neutrino sources are briefly reviewed and the neutrino processes relevant to the neutrino opacity in the stellar matter are discussed. Implications for the equation of state of neutrino-trapped matter are examined. (author) [pt

  14. Relic gravitational waves from light primordial black holes

    International Nuclear Information System (INIS)

    Dolgov, Alexander D.; Ejlli, Damian

    2011-01-01

    The energy density of relic gravitational waves (GWs) emitted by primordial black holes (PBHs) is calculated. We estimate the intensity of GWs produced at quantum and classical scattering of PBHs, the classical graviton emission from the PBH binaries in the early Universe, and the graviton emission due to PBH evaporation. If nonrelativistic PBHs dominated the cosmological energy density prior to their evaporation, the probability of formation of dense clusters of PBHs and their binaries in such clusters would be significant and the energy density of the generated gravitational waves in the present-day universe could exceed that produced by other known mechanisms. The intensity of these gravitational waves would be maximal in the GHz frequency band of the spectrum or higher and makes their observation very difficult by present detectors but also gives a rather good possibility to investigate it by present and future high-frequency gravitational waves electromagnetic detectors. However, the low-frequency part of the spectrum in the range f∼0.1-10 Hz may be detectable by the planned space interferometers DECIGO/BBO. For sufficiently long duration of the PBH matter-dominated stage, the cosmological energy fraction of GWs from inflation would be noticeably diluted.

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

    CERN Multimedia

    CERN. Geneva

    2015-01-01

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

  16. Physics of neutrino flavor transformation through matter–neutrino resonances

    Directory of Open Access Journals (Sweden)

    Meng-Ru Wu

    2016-01-01

    Full Text Available In astrophysical environments such as core-collapse supernovae and neutron star–neutron star or neutron star–black hole mergers where dense neutrino media are present, matter–neutrino resonances (MNRs can occur when the neutrino propagation potentials due to neutrino–electron and neutrino–neutrino forward scattering nearly cancel each other. We show that neutrino flavor transformation through MNRs can be explained by multiple adiabatic solutions similar to the Mikheyev–Smirnov–Wolfenstein mechanism. We find that for the normal neutrino mass hierarchy, neutrino flavor evolution through MNRs can be sensitive to the shape of neutrino spectra and the adiabaticity of the system, but such sensitivity is absent for the inverted hierarchy.

  17. Physics of neutrino flavor transformation through matter–neutrino resonances

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Meng-Ru, E-mail: mwu@theorie.ikp.physik.tu-darmstadt.de [Institut für Kernphysik (Theoriezentrum), Technische Universität Darmstadt, Schlossgartenstraße 2, 64289 Darmstadt (Germany); Duan, Huaiyu, E-mail: duan@unm.edu [Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131 (United States); Qian, Yong-Zhong, E-mail: qian@physics.umn.edu [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States)

    2016-01-10

    In astrophysical environments such as core-collapse supernovae and neutron star–neutron star or neutron star–black hole mergers where dense neutrino media are present, matter–neutrino resonances (MNRs) can occur when the neutrino propagation potentials due to neutrino–electron and neutrino–neutrino forward scattering nearly cancel each other. We show that neutrino flavor transformation through MNRs can be explained by multiple adiabatic solutions similar to the Mikheyev–Smirnov–Wolfenstein mechanism. We find that for the normal neutrino mass hierarchy, neutrino flavor evolution through MNRs can be sensitive to the shape of neutrino spectra and the adiabaticity of the system, but such sensitivity is absent for the inverted hierarchy.

  18. Neutrino magnetic moment contribution to the neutrino-deuteron reaction

    International Nuclear Information System (INIS)

    Tsuji, K.; Nakamura, S.; Sato, T.; Kubodera, K.; Myhrer, F.

    2004-01-01

    We study the effect of the neutrino magnetic moment on the neutrino-deuteron breakup reaction, using a method called the standard nuclear physics approach, which has already been well tested for several electroweak processes involving the deuteron

  19. Mapping the ecological dimensions and potential distributions of endangered relic shrubs in western Ordos biodiversity center.

    Science.gov (United States)

    Zhu, Geng-Ping; Li, Hui-Qi; Zhao, Li; Man, Liang; Liu, Qiang

    2016-05-20

    Potential distributions of endemic relic shrubs in western Ordos were poorly mapped, which hindered our implementation of proper conservation. Here we investigated the applicability of ecological niche modeling for endangered relic shrubs to detect areas of priority for biodiversity conservation and analyze differences in ecological niche spaces used by relic shrubs. We applied ordination and niche modeling techniques to assess main environmental drivers of five endemic relic shrubs in western Ordos, namely, Ammopiptanthus mongolicus, Amygdalus mongolica, Helianthemum songaricum, Potaninia mongolica, and Tetraena mongolica. We calculated niche overlap metrics in gridded environmental spaces and compared geographical projections of ecological niches to determine similarities and differences of niches occupied by relic shrubs. All studied taxa presented different responses to environmental factors, which resulted in a unique combination of niche conditions. Precipitation availability and soil quality characteristics play important roles in the distributions of most shrubs. Each relic shrub is constrained by a unique set of environmental conditions, the distribution of one species cannot be implied by the distribution of another, highlighting the inadequacy of one-fits-all type of conservation measure. Our stacked habitat suitability maps revealed regions around Yellow River, which are highly suitable for most species, thereby providing high conservation value.

  20. Flower symbolism and the cult of relics in medieval Serbia

    Directory of Open Access Journals (Sweden)

    Popović Danica

    2008-01-01

    Full Text Available The Life of archbishop Eustathios I [Jevstatije] (1279-1286, deserving head of the medieval Serbian Church and a saint, is a very interesting source for studying the cult of relics with the Serbs. This is not surprising considering that the Life was penned by one of the most illustrious of Eustathios' successors on the church throne, Daniel II [Danilo], a learned Athonite and unquestionable master of the hagiographie literary genre. In his account of the life of his distinguished predecessor, Daniel describes extensively the events constituting the key stage in the glorification of a saint, namely Eustathios' death and posthumous occurrences at his grave. As most holy men, Eustathios foresaw his own death, and he departed from this world serenely. He was buried, with due honours, in the 'marble grave' he had prepared for himself in the cathedral church of Holy Saviour at Žiča. In keeping with the well-established saint-making process, a few years after the funeral 'extraordinary signs' began to occur at the archbishop's grave, in this particular case, candlelight and a multitude of murmuring voices followed by the miraculous cure of an incurably ill person. These occurrences preceded the great miracle which, to the best of my knowledge, is unparalleled in the medieval Serbian practice of relic veneration. Namely, 'one day they found growing from his marble grave three flowers endowed with wondrous beauty and impossible to liken to anything else. For, indeed, they were not of earthly humidity or of union with flowers that grow from earth; but, o wonder, how a dry stone standing for so long in the church could send forth fragrant flowers, to the renewal of the sanctified one's body'. Flower metaphors occur in the Service to the holy archbishop Eustathios, yet another piece penned by Daniel II, notably in his paraphrases of Psalm 92, 12-14 ('The righteous shall flourish like the palm tree: he shall grow like a cedar in Lebanon. These that be

  1. Unifying leptogenesis, dark matter and high-energy neutrinos with right-handed neutrino mixing via Higgs portal

    Energy Technology Data Exchange (ETDEWEB)

    Bari, Pasquale Di; Ludl, Patrick Otto [Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ (United Kingdom); Palomares-Ruiz, Sergio [Instituto de Física Corpuscular (IFIC), CSIC-Universitat de València,Apartado de Correos 22085, E-46071 Valencia (Spain)

    2016-11-21

    We revisit a model in which neutrino masses and mixing are described by a two right-handed (RH) neutrino seesaw scenario, implying a strictly hierarchical light neutrino spectrum. A third decoupled RH neutrino, N{sub DM} with mass M{sub DM}, plays the role of cold dark matter (DM) and is produced by the mixing with a source RH neutrino, N{sub S} with mass M{sub S}, induced by Higgs portal interactions. The same interactions are also responsible for N{sub DM} decays. We discuss in detail the constraints coming from DM abundance and stability conditions showing that in the hierarchical case, for M{sub DM}≫M{sub S}, there is an allowed window on M{sub DM} values necessarily implying a contribution, from DM decays, to the high-energy neutrino flux recently detected by IceCube. We also show how the model can explain the matter-antimatter asymmetry of the Universe via leptogenesis in the quasi-degenerate limit. In this case, the DM mass should be within the range 300 GeV ≲M{sub S}neutrino flux and show the predicted event spectrum for two exemplary cases. Although DM decays, with a relatively hard spectrum, cannot account for all the IceCube high-energy data, we illustrate how this extra source of high-energy neutrinos could reasonably explain some potential features in the observed spectrum. In this way, this represents a unified scenario for leptogenesis and DM that could be tested during the next years with more high-energy neutrino events.

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

    OpenAIRE

    Tortola, M. A.

    2004-01-01

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

  3. Determination of the Atmospheric Neutrino Fluxes from Atmospheric Neutrino Data

    NARCIS (Netherlands)

    Gonzalez-Garcia, M. C.; Maltoni, M.; Rojo, J.

    2006-01-01

    The precise knowledge of the atmospheric neutrino fluxes is a key ingredient in the interpretation of the results from any atmospheric neutrino experiment. In the standard atmospheric neutrino data analysis, these fluxes are theoretical inputs obtained from sophisticated numerical calculations based

  4. Symplectic symmetry of the neutrino mass for many neutrino flavors

    International Nuclear Information System (INIS)

    Oeztuerk, N.; Ankara Univ.

    2001-01-01

    The algebraic structure of the neutrino mass Hamiltonian is presented for two neutrino flavors considering both Dirac and Majorana mass terms. It is shown that the algebra is Sp(8) and also discussed how the algebraic structure generalizes for the case of more than two neutrino flavors. (orig.)

  5. Neutrino Factory: status and prospects

    International Nuclear Information System (INIS)

    Long, K.

    2011-01-01

    The properties of the neutrino provide a unique window on physics beyond that described by the Standard Model. The study of sub-leading effects in neutrino oscillations has begun with the race to measure θ 13 consensus is emerging within the international community that a novel neutrino source is required to allow sensitive searches for leptonic CP violation to be carried out and the neutrino mass-hierarchy to be determined. The Neutrino Factory, in which intense neutrino beams are produced from the decay of muons, has been shown to out-perform the other proposed facilities. The physics case for the Neutrino Factory will be reviewed and the baseline design of the facility being developed by the International Design Study for the Neutrino Factory (the IDS-NF) collaboration will be described.

  6. Steps towards the Neutrino Factory

    International Nuclear Information System (INIS)

    Long, K.

    2012-01-01

    The properties of the neutrino provide a unique window on physics beyond that described by the Standard Model. The study of sub-leading effects in neutrino oscillations has begun with the race to measure θ 13 . A consensus is emerging within the international community that a novel neutrino source is required to allow sensitive searches for leptonic CP violation to be carried out and the neutrino mass-hierarchy to be determined. The Neutrino Factory, in which intense neutrino beams are produced from the decay of muons, has been shown to out-perform the other proposed facilities. The physics case for the Neutrino Factory will be reviewed and the baseline design of the facility being developed by the International Design Study for the Neutrino Factory (the IDS-NF) collaboration will be described.

  7. Experimental studies of neutrino oscillations

    CERN Document Server

    Kajita, Takaaki

    2016-01-01

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

  8. CrossRef Neutrino factories

    CERN Document Server

    Wildner, Elena

    2016-01-01

    Neutrinos are produced by many processes in our universe. These elusive particles reach the earth having a certain energy permitting them to react with nuclei in detectors that are specifically designed to probe their properties. However, to get higher intensities and higher energy neutrinos for better statistics and better physics reach, the use of accelerators is necessary to advance in the field of neutrino research. To produce neutrinos with an accelerator, one needs to send a high power beam onto a target to get particles or isotopes that produce neutrinos with the required properties, by decay. The parent particles have to be collected and prepared for injection into an accelerating structure. Accelerator-based experiments can tune the energy of the produced neutrinos by boosting and controlling the energy of the parent particle. The produced neutrinos will travel the distance between the source and the detector, generally through earth; the distance the neutrino travels through earth, the energy of the...

  9. Simulating nonlinear neutrino flavor evolution

    Science.gov (United States)

    Duan, H.; Fuller, G. M.; Carlson, J.

    2008-10-01

    We discuss a new kind of astrophysical transport problem: the coherent evolution of neutrino flavor in core collapse supernovae. Solution of this problem requires a numerical approach which can simulate accurately the quantum mechanical coupling of intersecting neutrino trajectories and the associated nonlinearity which characterizes neutrino flavor conversion. We describe here the two codes developed to attack this problem. We also describe the surprising phenomena revealed by these numerical calculations. Chief among these is that the nonlinearities in the problem can engineer neutrino flavor transformation which is dramatically different to that in standard Mikheyev Smirnov Wolfenstein treatments. This happens even though the neutrino mass-squared differences are measured to be small, and even when neutrino self-coupling is sub-dominant. Our numerical work has revealed potential signatures which, if detected in the neutrino burst from a Galactic core collapse event, could reveal heretofore unmeasurable properties of the neutrinos, such as the mass hierarchy and vacuum mixing angle θ13.

  10. Catching the Highest Energy Neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Stanev, Todor [Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States)

    2011-08-15

    We briefly discuss the possible sources of ultrahigh energy neutrinos and the methods for their detection. Then we present the results obtained by different experiments for detection of the highest energy neutrinos.

  11. Dark matter and neutrino mass from the smallest non-Abelian chiral dark sector

    Science.gov (United States)

    Berryman, Jeffrey M.; de Gouvêa, André; Kelly, Kevin J.; Zhang, Yue

    2017-10-01

    All pieces of concrete evidence for phenomena outside the standard model (SM)—neutrino masses and dark matter—are consistent with the existence of new degrees of freedom that interact very weakly, if at all, with those in the SM. We propose that these new degrees of freedom organize themselves into a simple dark sector, a chiral S U (3 )×S U (2 ) gauge theory with the smallest nontrivial fermion content. Similar to the SM, the dark S U (2 ) is spontaneously broken while the dark S U (3 ) confines at low energies. At the renormalizable level, the dark sector contains massless fermions—dark leptons—and stable massive particles—dark protons. We find that dark protons with masses between 10 and 100 TeV satisfy all current cosmological and astrophysical observations concerning dark matter even if dark protons are a symmetric thermal relic. The dark leptons play the role of right-handed neutrinos and allow simple realizations of the seesaw mechanism or the possibility that neutrinos are Dirac fermions. In the latter case, neutrino masses are also parametrically different from charged-fermion masses and the lightest neutrino is predicted to be massless. Since the new "neutrino" and "dark-matter" degrees of freedom interact with one another, these two new-physics phenomena are intertwined. Dark leptons play a nontrivial role in early Universe cosmology while indirect searches for dark matter involve, decisively, dark-matter annihilations into dark leptons. These, in turn, may lead to observable signatures at high-energy neutrino and gamma-ray observatories, especially once one accounts for the potential Sommerfeld enhancement of the annihilation cross section, derived from the low-energy dark-sector effective theory, a possibility we explore quantitatively in some detail.

  12. Physics of the neutrino mass

    International Nuclear Information System (INIS)

    Mohapatra, R N

    2004-01-01

    Recent neutrino oscillation experiments have yielded valuable information on the nature of neutrino masses and mixings and qualify as the first evidence for physics beyond the standard model. Even though we are far from a complete understanding of the new physics implied by them, there are many useful hints. As the next precision era in neutrino physics is about to be launched, we review the physics of neutrino mass: what we have learned and what we are going to learn

  13. The sun and the neutrinos

    International Nuclear Information System (INIS)

    Forgacsne Dajka, E.

    2000-01-01

    A review of the solar neutrino puzzle is given. The main processes in the sun, the pp-chain and the CNO cycle are described. The solar neutrino puzzle, i.e. the fact that the detected amount of neutrinos coming from the sun is less than the amount predicted by the solar model is discussed. The first generation solar neutrino experiments are presented. (K.A.)

  14. Eighty years of neutrino physics

    International Nuclear Information System (INIS)

    Roy, D.P.

    2009-01-01

    This is a pedagogical overview of neutrino physics from the invention of neutrino by Pauli in 1930 to the precise measurement of neutrino mass and mixing parameters via neutrino oscillation experiments in recent years. I have tried to pitch it at the level of undergraduate students, occasionally cutting corners to avoid the use of advanced mathematical tools. I hope it will be useful in introducing this exciting field to a broad group of young physicists. (author)

  15. Relics of the cosmological quark-hadron phase transition

    International Nuclear Information System (INIS)

    Sinha, Bikash

    2001-01-01

    In this talk I will not dwell further on the nature of the Q -> H transition, Instead, I will simply assume that it is a phase transition, and further, a first-order phase transition, in which case, there is a possibility that a particular kind of relics called quark nuggets (QNs) containing a large fraction of the net baryon number of the universe may have been formed at the end of such a phase transition. The QNs would have tremendous implications for cosmology and astrophysics. In particular, they can be a good candidate for the baryonic dark matter in the universe provided they can survive up to the present epoch. The QNs which survived and floating around the universe, is there any connection with the recently discovered MACHOs between the earth and the Large Magellanic clouds. The QNs are hypothesized to be made of 'strange matter' which is composed of a roughly equal mixture of u, d, and s quarks at a density ≥ nuclear density. It has been hypothesized that at zero temperature and zero pressure the true ground state of hadronic matter could be SM rather than 56 Fe, the energy per baryon in SM could be lower that in ordinary nuclear matter. The latter would, however, still be effectively stable against decay would require high order simultaneous weak interaction process with a life-time much greater than the age of the universe. For certain ranges of values of parameters involved, namely, the QCD fine structure constant (α c ), mass of the strange quark (m s ), the vacuum bag energy (B), the hypothesis of SM being the absolutely stable of hadronic matter has been found to be quite plausible. (author)

  16. Gravitationally confined relativistic neutrinos

    Science.gov (United States)

    Vayenas, C. G.; Fokas, A. S.; Grigoriou, D.

    2017-09-01

    Combining special relativity, the equivalence principle, and Newton’s universal gravitational law with gravitational rather than rest masses, one finds that gravitational interactions between relativistic neutrinos with kinetic energies above 50 MeV are very strong and can lead to the formation of gravitationally confined composite structures with the mass and other properties of hadrons. One may model such structures by considering three neutrinos moving symmetrically on a circular orbit under the influence of their gravitational attraction, and by assuming quantization of their angular momentum, as in the Bohr model of the H atom. The model contains no adjustable parameters and its solution, using a neutrino rest mass of 0.05 eV/c2, leads to composite state radii close to 1 fm and composite state masses close to 1 GeV/c2. Similar models of relativistic rotating electron - neutrino pairs give a mass of 81 GeV/c2, close to that of W bosons. This novel mechanism of generating mass suggests that the Higgs mass generation mechanism can be modeled as a latent gravitational field which gets activated by relativistic neutrinos.

  17. The CERN Neutrino Platform

    CERN Document Server

    Bordoni, Stefania

    2018-01-01

    The long-baseline neutrino programme has been classified as one of the four highest-priority sci- entific objectives in 2013 by the European Strategy for Particle Physics. The Neutrino Platform is the CERN venture to foster and support the next generation of accelerator-based neutrino os- cillation experiments. Part of the present CERN Medium-Term Plan, the Neutrino Platform provide facilities to develop and prototype the next generation of neutrino detectors and contribute to unify the European neu- trino community towards the US and Japanese projects. A significative effort is made on R&D; for LAr TPC technologies: two big LAr TPC prototypes for the DUNE far detector are under con- struction at CERN. Those detectors will be exposed in 2018 to an entirely new and NP-dedicated beam-line from the SPS which will provide electron, muon and hadron beams with energies in the range of sub-GeV to a few GeV. Other projects are also presently under development: one can cite the refurbishing and shipping to the US ...

  18. Bruno Pontecorvo and solar neutrinos

    International Nuclear Information System (INIS)

    MCDONALD, A. B.

    2014-01-01

    Bruno Pontecorvo had a very substantial impact on measurements of solar neutrinos, proposing a technique in 1948 that led to measurements by Davis and proposing that neutrinos could oscillate, a process that has been found to influence observed fluxes substantially. The past history and future prospects of solar neutrino measurements are reviewed, including a discussion of the contributions by Pontecorvo.

  19. Neutrinos from the Milky Way

    NARCIS (Netherlands)

    Visser, Erwin Lourens

    2015-01-01

    A guaranteed source of neutrinos is the production in cosmic ray interactions with the interstellar matter in our Galaxy. The signal has never been detected however and only an upper limit on this flux of neutrinos has been published by the AMANDA-II detector. The ANTARES neutrino telescope, located

  20. Neutrino mass sum-rule

    Science.gov (United States)

    Damanik, Asan

    2018-03-01

    Neutrino mass sum-rele is a very important research subject from theoretical side because neutrino oscillation experiment only gave us two squared-mass differences and three mixing angles. We review neutrino mass sum-rule in literature that have been reported by many authors and discuss its phenomenological implications.

  1. Matter effects in neutrino oscillations

    International Nuclear Information System (INIS)

    Dass, G.V.

    1989-01-01

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

  2. Systems of neutrinos with mass

    International Nuclear Information System (INIS)

    Groot, S.R. de

    1984-01-01

    From the formalism of relativistic kinetic theory and the weak interaction Lagrangian the volume viscosity of a massive neutrino system is derived. Its value is calculated as a function of the neutrino mass and the temperature. Its role in the way of expanding or contraction of neutrino clouds in the universe is discussed. (Author) [pt

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

    International Nuclear Information System (INIS)

    Leung, C.N.

    1987-01-01

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

  4. Determination of the atmospheric neutrino fluxes from atmospheric neutrino data

    International Nuclear Information System (INIS)

    Gonzalez-Garcia, C.; Maltoni, M.; Rojo, J.

    2006-06-01

    The precise knowledge of the atmospheric neutrino fluxes is a key ingredient in the interpretation of the results from any atmospheric neutrino experiment. In the standard data analysis, these fluxes are theoretical inputs obtained from sophisticated numerical calculations based on the convolution of the primary cosmic ray spectrum with the expected yield of neutrinos per incident cosmic ray. In this work we present an alternative approach to the determination of the atmospheric neutrino fluxes based on the direct extraction from the experimental data on neutrino event rates. The extraction is achieved by means of a combination of artificial neural networks as interpolants and Monte Carlo methods for faithful error estimation. (author)

  5. Determination of the atmospheric neutrino fluxes from atmospheric neutrino data

    International Nuclear Information System (INIS)

    Gonzalez-Garcia, Concepcion; Maltoni, Michele; Rojo, Joan

    2006-01-01

    The precise knowledge of the atmospheric neutrino fluxes is a key ingredient in the interpretation of the results from any atmospheric neutrino experiment. In the standard data analysis, these fluxes are theoretical inputs obtained from sophisticated numerical calculations based on the convolution of the primary cosmic ray spectrum with the expected yield of neutrinos per incident cosmic ray. In this work we present an alternative approach to the determination of the atmospheric neutrino fluxes based on the direct extraction from the experimental data on neutrino event rates. The extraction is achieved by means of a combination of artificial neural networks as interpolants and Monte Carlo methods for faithful error estimation

  6. Supernova Neutrino-Process and Implication in Neutrino Oscillation

    Science.gov (United States)

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

    2012-08-01

    We studied the supernova nucleosynthesis induced by neutrino interactions and found that several isotopes of rare elements like 7Li, 11B, 138La, 180Ta and many others are predominantly produced by the neutrino-process in core-collapse supernovae. These isotopes are strongly affected by the neutrino flavor oscillation due to the MSW (Mikheyev-Smirnov-Wolfenstein) effect. We here propose a new novel method to determine the unknown neutrino oscillation parameters, θ13 and mass hierarchy simultaneously from the supernova neutrino-process, combined with the r-process for heavy-element synthsis and the Galactic chemical evolution on light nuclei.

  7. Geometric phase of neutrinos: Differences between Dirac and Majorana neutrinos

    Science.gov (United States)

    Capolupo, A.; Giampaolo, S. M.; Hiesmayr, B. C.; Vitiello, G.

    2018-05-01

    We analyze the non-cyclic geometric phase for neutrinos. We find that the geometric phase and the total phase associated to the mixing phenomenon provide a theoretical tool to distinguish between Dirac and Majorana neutrinos. Our results hold for neutrinos propagating in vacuum and through the matter. We feed the values of the experimental parameters in our formulas in order to make contact with experiments. Although it remains an open question how the geometric phase of neutrinos could be detected, our theoretical results may open new scenarios in the investigation of the neutrino nature.

  8. TURBULENT COSMIC-RAY REACCELERATION AT RADIO RELICS AND HALOS IN CLUSTERS OF GALAXIES

    International Nuclear Information System (INIS)

    Fujita, Yutaka; Takizawa, Motokazu; Yamazaki, Ryo; Akamatsu, Hiroki; Ohno, Hiroshi

    2015-01-01

    Radio relics are synchrotron emission found on the periphery of galaxy clusters. From the position and the morphology, it is often believed that the relics are generated by cosmic-ray (CR) electrons accelerated at shocks through a diffusive shock acceleration (DSA) mechanism. However, some radio relics have harder spectra than the prediction of the standard DSA model. One example is observed in the cluster 1RXS J0603.3+4214, which is often called the “Toothbrush Cluster.” Interestingly, the position of the relic is shifted from that of a possible shock. In this study, we show that these discrepancies in the spectrum and the position can be solved if turbulent (re)acceleration is very effective behind the shock. This means that for some relics turbulent reacceleration may be the main mechanism to produce high-energy electrons, contrary to the common belief that it is the DSA. Moreover, we show that for efficient reacceleration, the effective mean free path of the electrons has to be much smaller than their Coulomb mean free path. We also study the merging cluster 1E 0657−56, or the “Bullet Cluster,” in which a radio relic has not been found at the position of the prominent shock ahead of the bullet. We indicate that a possible relic at the shock is obscured by the observed large radio halo that is generated by strong turbulence behind the shock. We propose a simple explanation of the morphological differences of radio emission among the Toothbrush, the Bullet, and the Sausage (CIZA J2242.8+5301) Clusters

  9. Neutrino mixing and big bang nucleosynthesis

    Science.gov (United States)

    Bell, Nicole

    2003-04-01

    We analyse active-active neutrino mixing in the early universe and show that transformation of neutrino-antineutrino asymmetries between flavours is unavoidable when neutrino mixing angles are large. This process is a standard Mikheyev-Smirnov-Wolfenstein flavour transformation, modified by the synchronisation of momentum states which results from neutrino-neutrino forward scattering. The new constraints placed on neutrino asymmetries eliminate the possibility of degenerate big bang nucleosynthesis.Implications of active-sterile neutrino mixing will also be reviewed.

  10. Workshop on low energy neutrino physics

    International Nuclear Information System (INIS)

    2009-01-01

    The main topics of the workshop are: the determination of the neutrino mixing angle theta-13, the experiments concerning the monitoring of reactors based on the measurement of neutrino spectra, solar neutrinos, supernovae neutrinos, geo-neutrinos, neutrino properties, neutrinoless double beta decay and future low energy neutrino detectors. This document gathers together the program of the workshop, the slides of the presentations, some abstracts and some posters

  11. Neutrino magnetic moments and the solar neutrino problem

    Energy Technology Data Exchange (ETDEWEB)

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

    1994-08-01

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

  12. Neutrino magnetic moments and the solar neutrino problem

    International Nuclear Information System (INIS)

    Akhmedov, E.Kh.; Valencia Univ.

    1994-01-01

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

  13. Signatures of the neutrino mass hierarchy in supernova neutrinos

    International Nuclear Information System (INIS)

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

    2015-01-01

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

  14. Entanglement in neutrino oscillations

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-03-15

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

  15. Neutrino physics: Summary talk

    International Nuclear Information System (INIS)

    Marciano, W.J.

    1989-04-01

    This paper is organized as follows: First, I describe the state of neutrino phenomenology. Emphasis is placed on sin 2 θ W , its present status and future prospects. In addition, some signatures of ''new physics'' are described. Then, kaon physics at Fermilab is briefly discussed. I concentrate on the interesting rare decay K L → π 0 e + e - which may be a clean probe direct CP violation. Neutrino mass, mixing, and electromagnetic moments are surveyed. There, I describe the present state and future direction of accelerator based experiments. Finally, I conclude with an outlook on the future. Throughout this summary, I have drawn from and incorporated ideas discussed by other speakers at this workshop. However, I have tried to combine their ideas with my own perspective on neutrino physics and where it is headed. 49 refs., 3 figs., 4 tabs

  16. Neutrino physics after boomerang

    International Nuclear Information System (INIS)

    Hannestad, Steen

    2001-01-01

    A new generation of Cosmic Microwave Background Radiation (CMBR) experiments are currently providing the first precision measurements of fluctuations in the CMBR. These fluctuations hold information about all the fundamental cosmological parameters, and the experiments have already confirmed beyond reasonable doubt that the geometry of the universe is very close to being flat. The new CMBR experiments can also be used to probe particle physics beyond the standard model. For instance, data from the new Boomerang experiment yield an upper limit on the effective number of neutrinos present at recombination, N ν ≤ 13 (95% C.L.). This already puts significant constraints on many non-standard neutrino scenarios, such as the possible bulk neutrino modes expected in theories with large extra dimensions. The upcoming satellite experiments will improve the sensitivity of the CMBR by almost an order of magnitude and make the CMBR an excellent laboratory for precision particle physics

  17. Phenomenology of atmospheric neutrinos

    Directory of Open Access Journals (Sweden)

    Fedynitch Anatoli

    2016-01-01

    Full Text Available The detection of astrophysical neutrinos, certainly a break-through result, introduced new experimental challenges and fundamental questions about acceleration mechanisms of cosmic rays. On one hand IceCube succeeded in finding an unambiguous proof for the existence of a diffuse astrophysical neutrino flux, on the other hand the precise determination of its spectral index and normalization requires a better knowledge about the atmospheric background at hundreds of TeV and PeV energies. Atmospheric neutrinos in this energy range originate mostly from decays of heavy-flavor mesons, which production in the phase space relevant for prompt leptons is uncertain. Current accelerator-based experiments are limited by detector acceptance and not so much by the collision energy. This paper recaps phenomenological aspects of atmospheric leptons and calculation methods, linking recent progress in flux predictions with particle physics at colliders, in particular the Large Hadron Collider.

  18. Astrophysics and neutrinos

    CERN Document Server

    Harigel, G G

    1997-01-01

    This seminar is primarily intended for CERN guides. The formation of sun-like stars, their life cycle, and their final destiny will be explained in simple terms, appropriate for the majority of our visitors. An overview of the nuclear reaction chains in our sun will presented (Standard Solar Model), with special emphasis on the production of neutrinos and their measurement in underground detectors. These detectors are also able to record high-energy cosmic neutrinos. Since many properties of neutrinos are still unknown, a brief description of table-top and nuclear reactor experiments is included, as well as those using beams from particle accelerators. Measurements with a variety of space telescopes complement the knowledge of our universe, previously limited to the visible range of the electromagnetic spectrum.

  19. Entanglement in neutrino oscillations

    International Nuclear Information System (INIS)

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

    2009-01-01

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

  20. Toward observational neutrino astrophysics

    International Nuclear Information System (INIS)

    Koshiba, M.

    1988-01-01

    It is true that: (1) The first observation of the neutrino burst from the supernova SN1987a by Kamiokande-II which was immediately confirmed by IBM; and (2) the first real-time, directional, and spectral observation of solar 8 B neutrinos also by Kamiokande-II could perhaps be considered as signalling the birth of observational astrophysics. The field, however, is still in its infancy and is crying out for tender loving care. Namely, while the construction of astronomy requires the time and the direction of the signal and that of astrophysics requires, in addition to the spectral information, the observations of (1) could not give the directional information and the results of both (1) and (2) are still suffering from the meager statistics. How do we remedy this situation to let this new born science of observational neutrino astrophysics grow healthy. This is what the author addresses in this talk. 15 refs., 8 figs

  1. Neutrinos and supernova collapse

    International Nuclear Information System (INIS)

    Colgate, S.A.; Petschek, A.G.

    1980-01-01

    The neutrino emission resulting from stellar collapse and supernova formation is reviewed. The electron capture and consequent neutronization of the collapsing stellar matter at the end of evolution determines both the initial adiabat of core collapse as well as the trapped lepton fraction. The initial lepton fraction, Y/sub l/ = .48 supplies the pressure for neutral support of the star at the Chandrasekhar limit. High trapping values, Y/sub l/ = .4, lead to soft core collapses; low values to harder collapses. The value of Y/sub l/ is presently in dispute. The neutrino emission from initial electron capture is relatively small. A strong core-bounce shock releases both electron neutrino as well as thermal muon and tau neutrinos. Subsequent neutrino emission and cooling can sometimes lead to an unstable buoyancy gradient in the core in which case unstable core overturn is expected. Calculations have already shown the importance of the largest possible eddy or equivalently the lowest mode of overturn. Present models of low lepton trapping ratio lead to high entropy creation by the reflected shock and the stabilization of the core matter against overturn. In such cases the exterior matter must cool below an entropy of approximately s/k approx. = 2 to become unstable. This may require too long a time approximately one second for neutrino cooling from a neutrinosphere at rho approx. = 2 x 10 12 g cm -3 . On the other hand, high values of Y/sub l/ such as .4 lead to softer bounces at lower density and values of the critical stabilizing entropy of 3 or higher. Under such circumstances, core overturn can still occur

  2. Neutrino oscillation: status and outlooks

    International Nuclear Information System (INIS)

    Nedelec, P.

    1994-01-01

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

  3. Detection of the neutrino

    International Nuclear Information System (INIS)

    Reines, F.

    1989-01-01

    Using the nuclear bomb developed at Los Alamos as an intense source of neutrinos, the author aimed to build a detector suitable to observe this newly predicted particle for the first time during his work there in the early 1950s. He chose to work on the reaction of beta decay inversion. The discovery of organic liquid scintillation counters brought the possibility of neutrino detection one place closer. Delayed coincidence between positron and neutron capture pulses were planned as a way to eliminate background signals. Experiments finally went ahead using nuclear reactors rather than bombs and was successful although many problems with shielding, and the sheer scale of the apparatus were encountered. (UK)

  4. Baryogenesis and neutrino masses

    International Nuclear Information System (INIS)

    Peccei, R.D.

    1992-01-01

    The erasure of any preexisting B+L asymmetry in the universe in its late stages suggests that the B asymmetry observed today either originated at the electroweak scale or it arose from an original L asymmetry. For the latter case to be viable either neutrino masses are much below the eV scale or the L asymmetry itself is generated at an intermediate scale. Several features of the generation of a B asymmetry via an L asymmetry are discussed, including the interesting possibility that the present baryon asymmetry in the universe originates as a result of CP violating phases in the neutrino mass matrix

  5. Geo-neutrino review

    International Nuclear Information System (INIS)

    Tolich, N.

    2012-01-01

    The principal source of energy for dynamic processes of the earth, such as plate tectonics is thought to come from the radioactive decays of 238 U, 232 Th, and 40 K within the earth. These decays produce electron-antineutrinos, so-called geo-neutrinos, the measurement of which near the earth's surface allows for a direct measure of the total radiogenic heat production in the earth. The KamLAND and Borexino experiments have both measured a geo-neutrino flux significantly greater than zero. As shown in these proceedings, more precise future measurements will significantly constrain earth composition models.

  6. Atmospheric neutrino fluxes

    International Nuclear Information System (INIS)

    Honda, M.; Kasahara, K.; Hidaka, K.; Midorikawa, S.

    1990-02-01

    A detailed Monte Carlo simulation of neutrino fluxes of atmospheric origin is made taking into account the muon polarization effect on neutrinos from muon decay. We calculate the fluxes with energies above 3 MeV for future experiments. There still remains a significant discrepancy between the calculated (ν e +antiν e )/(ν μ +antiν μ ) ratio and that observed by the Kamiokande group. However, the ratio evaluated at the Frejus site shows a good agreement with the data. (author)

  7. Neutrino oscillations at LAMPF

    International Nuclear Information System (INIS)

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

    1985-01-01

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

  8. Towards absolute neutrino masses

    Energy Technology Data Exchange (ETDEWEB)

    Vogel, Petr [Kellogg Radiation Laboratory 106-38, Caltech, Pasadena, CA 91125 (United States)

    2007-06-15

    Various ways of determining the absolute neutrino masses are briefly reviewed and their sensitivities compared. The apparent tension between the announced but unconfirmed observation of the 0{nu}{beta}{beta} decay and the neutrino mass upper limit based on observational cosmology is used as an example of what could happen eventually. The possibility of a 'nonstandard' mechanism of the 0{nu}{beta}{beta} decay is stressed and the ways of deciding which of the possible mechanisms is actually operational are described. The importance of the 0{nu}{beta}{beta} nuclear matrix elements is discussed and their uncertainty estimated.

  9. Neutrino interactions with nuclei

    CERN Document Server

    Martini, M; Ericson, M; Marteau, J

    2009-01-01

    We present a model for neutrino-nucleus scattering in the energy region relevant for present and forthcoming neutrino-oscillation experiments. The model is based on the RPA treatment of the nuclear responses in the quasi-elastic and Delta-resonance region. It includes also in a phenomenological way nucleon knock-out. It aims at the description, within a single framework, of several final state channels i.e. quasi-elastic, incoherent and coherent one-pion production and two- or several-nucleon knock-out.

  10. Neutrino properties from cosmology

    CERN Multimedia

    CERN. Geneva

    2013-01-01

    Future, massive large-scale structure survey have been presented and approved.On the theory side, a significant effort has bene devoted to achieve better modeling of small scale clustering that is of cosmological non-linearities. As a result it has become clear that forthcoming cosmological data have enough statitsical power to detect the effect of non-zero neutrino mass (even at the lower mass scale limit imposed by oscillations) and to constrain the absolute neutrino mass scale.Cosmological data can also constrain the numb...

  11. Sterile Neutrino Search with MINOS

    International Nuclear Information System (INIS)

    Devan, Alena V.

    2015-01-01

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

  12. Sterile Neutrino Search with MINOS

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-08-01

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

  13. Experimental data on solar neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Ludhova, Livia [INFN, Milano (Italy)

    2016-04-15

    Neutrino physics continues to be a very active research field, full of opened fundamental questions reaching even beyond the Standard Model of elementary particles and towards a possible new physics. Solar neutrinos have played a fundamental historical role in the discovery of the phenomenon of neutrino oscillations and thus non-zero neutrino mass. Even today, the study of solar neutrinos provides an important insight both into the neutrino as well as into the stellar and solar physics. In this section we give an overview of the most important solar-neutrino measurements from the historical ones up to the most recent ones. We cover the results from the experiments using radio-chemic (Homestake, SAGE, GNO, GALLEX), water Cherenkov (Kamiokande, Super-Kamiokande, SNO), and the liquid-scintillator (Borexino, KamLAND) detection techniques. (orig.)

  14. Beam and experiments summary [neutrino studies

    CERN Document Server

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

    2000-01-01

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

  15. Right-handed neutrino dark matter under the B−L gauge interaction

    Energy Technology Data Exchange (ETDEWEB)

    Kaneta, Kunio [Center for Theoretical Physics of the Universe, Institute for Basic Science,Daejeon 34051 (Korea, Republic of); Kang, Zhaofeng [School of Physics, Korea Institute for Advanced Study,Seoul 02455 (Korea, Republic of); Lee, Hye-Sung [Center for Theoretical Physics of the Universe, Institute for Basic Science,Daejeon 34051 (Korea, Republic of)

    2017-02-07

    We study the right-handed neutrino (RHN) dark matter candidate in the minimal U(1){sub B−L} gauge extension of the standard model. The U(1){sub B−L} gauge symmetry offers three RHNs which can address the origin of the neutrino mass, the relic dark matter, and the matter-antimatter asymmetry of the universe. The lightest among the three is taken as the dark matter candidate, which is under the B−L gauge interaction. We investigate various scenarios for this dark matter candidate with the correct relic density by means of the freeze-out or freeze-in mechanism. A viable RHN dark matter mass lies in a wide range including keV to TeV scale. We emphasize the sub-electroweak scale light B−L gauge boson case, and identify the parameter region motivated from the dark matter physics, which can be tested with the planned experiments including the CERN SHiP experiment.

  16. An Experimentalist's Overview of Solar Neutrinos

    Science.gov (United States)

    Oser, Scott M.

    2012-02-01

    Four decades of solar neutrino research have demonstrated that solar models do a remarkable job of predicting the neutrino fluxes from the Sun, to the extent that solar neutrinos can now serve as a calibrated neutrino source for experiments to understand neutrino oscillations and mixing. In this review article I will highlight the most significant experimental results, with emphasis on the latest model-independent measurements from the Sudbury Neutrino Observatory. The solar neutrino fluxes are seen to be generally well-determined experimentally, with no indications of time variability, while future experiments will elucidate the lower energy part of the neutrino spectrum, especially pep and CNO neutrinos.

  17. An Experimentalist's Overview of Solar Neutrinos

    International Nuclear Information System (INIS)

    Oser, Scott M

    2012-01-01

    Four decades of solar neutrino research have demonstrated that solar models do a remarkable job of predicting the neutrino fluxes from the Sun, to the extent that solar neutrinos can now serve as a calibrated neutrino source for experiments to understand neutrino oscillations and mixing. In this review article I will highlight the most significant experimental results, with emphasis on the latest model-independent measurements from the Sudbury Neutrino Observatory. The solar neutrino fluxes are seen to be generally well-determined experimentally, with no indications of time variability, while future experiments will elucidate the lower energy part of the neutrino spectrum, especially pep and CNO neutrinos.

  18. Neutrino oscillations in the early universe

    International Nuclear Information System (INIS)

    Enqvist, K.

    1990-01-01

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

  19. Three flavour oscillation interpretation of neutrino data

    Indian Academy of Sciences (India)

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

  20. Non-thermal production of minimal dark matter via right-handed neutrino decay

    International Nuclear Information System (INIS)

    Aoki, Mayumi; Toma, Takashi; Vicente, Avelino

    2015-01-01

    Minimal Dark Matter (MDM) stands as one of the simplest dark matter scenarios. In MDM models, annihilation and co-annihilation processes among the members of the MDM multiplet are usually very efficient, pushing the dark matter mass above O(10) TeV in order to reproduce the observed dark matter relic density. Motivated by this little drawback, in this paper we consider an extension of the MDM scenario by three right-handed neutrinos. Two specific choices for the MDM multiplet are studied: a fermionic SU(2) L quintuplet and a scalar SU(2) L septuplet. The lightest right-handed neutrino, with tiny Yukawa couplings, never reaches thermal equilibrium in the early universe and is produced by freeze-in. This creates a link between dark matter and neutrino physics: dark matter can be non-thermally produced by the decay of the lightest right-handed neutrino after freeze-out, allowing to lower significantly the dark matter mass. We discuss the phenomenology of the non-thermally produced MDM and, taking into account significant Sommerfeld corrections, we find that the dark matter mass must have some specific values in order not to be in conflict with the current bounds from gamma-ray observations

  1. Can sterile neutrinos be ruled out as warm dark matter candidates?

    CERN Document Server

    Viel, M; Hähnelt, M G; Matarrese, S; Riotto, Antonio; Viel, Matteo; Lesgourgues, Julien; Haehnelt, Martin G.; Matarrese, Sabino; Riotto, Antonio

    2006-01-01

    We present constraints on the mass of Warm Dark Matter (WDM) particles from a combined analysis of the matter power spectrum inferred from the SDSS (Sloan Digital Sky Survey) Lyman-alpha flux power spectrum at 2.2 10 keV (2 sigma) if the WDM consists of sterile neutrinos and m_wdm > 2 keV (2 sigma) for early decoupled thermal relics. These results significantly improve our previous estimates based on high-resolution Lyman-alpha forest data at lower redshift. Our new limits are consistent with those of Seljak et al. (2006), albeit ~ 30 % smaller. If we combine this bound with the constraint derived from X-ray flux observations in the Coma cluster periphery (Boyarsky et al.), we find that the only allowed sterile neutrino mass is ~ 10 keV (in the standard production scenario with non-resonant neutrino oscillations). Adding constraints based on X-ray fluxes from the Andromeda galaxy or the Milky Way, we find that dark matter particles cannot be sterile neutrinos, unless the latter are produced by resonant oscill...

  2. Non-thermal production of minimal dark matter via right-handed neutrino decay

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, Mayumi [Institute for Theoretical Physics, Kanazawa University,Kanazawa 920-1192 (Japan); Toma, Takashi [Laboratoire de Physique Théorique, CNRS - UMR 8627, Université de Paris-Sud 11,F-91405 Orsay Cedex (France); Vicente, Avelino [IFPA, Dep. AGO, Université de Liège,Bat B5, Sart-Tilman B-4000 Liège 1 (Belgium); Instituto de Física Corpuscular, CSIC-Universitat de València,Apdo. 22085, E-46071 Valencia (Spain)

    2015-09-29

    Minimal Dark Matter (MDM) stands as one of the simplest dark matter scenarios. In MDM models, annihilation and co-annihilation processes among the members of the MDM multiplet are usually very efficient, pushing the dark matter mass above O(10) TeV in order to reproduce the observed dark matter relic density. Motivated by this little drawback, in this paper we consider an extension of the MDM scenario by three right-handed neutrinos. Two specific choices for the MDM multiplet are studied: a fermionic SU(2){sub L} quintuplet and a scalar SU(2){sub L} septuplet. The lightest right-handed neutrino, with tiny Yukawa couplings, never reaches thermal equilibrium in the early universe and is produced by freeze-in. This creates a link between dark matter and neutrino physics: dark matter can be non-thermally produced by the decay of the lightest right-handed neutrino after freeze-out, allowing to lower significantly the dark matter mass. We discuss the phenomenology of the non-thermally produced MDM and, taking into account significant Sommerfeld corrections, we find that the dark matter mass must have some specific values in order not to be in conflict with the current bounds from gamma-ray observations.

  3. Non-thermal production of minimal dark matter via right-handed neutrino decay

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, Mayumi [Institute for Theoretical Physics, Kanazawa University, Kanazawa 920-1192 (Japan); Toma, Takashi [Laboratoire de Physique Théorique, CNRS - UMR 8627, Université de Paris-Sud 11, F-91405 Orsay Cedex (France); Vicente, Avelino, E-mail: mayumi@hep.s.kanazawa-u.ac.jp, E-mail: takashi.toma@th.u-psud.fr, E-mail: Avelino.Vicente@ulg.ac.be [IFPA, Dep. AGO, Université de Liège, Bat B5, Sart-Tilman B-4000 Liège 1 (Belgium)

    2015-09-01

    Minimal Dark Matter (MDM) stands as one of the simplest dark matter scenarios. In MDM models, annihilation and co-annihilation processes among the members of the MDM multiplet are usually very efficient, pushing the dark matter mass above O(10) TeV in order to reproduce the observed dark matter relic density. Motivated by this little drawback, in this paper we consider an extension of the MDM scenario by three right-handed neutrinos. Two specific choices for the MDM multiplet are studied: a fermionic SU(2){sub L} quintuplet and a scalar SU(2){sub L} septuplet. The lightest right-handed neutrino, with tiny Yukawa couplings, never reaches thermal equilibrium in the early universe and is produced by freeze-in. This creates a link between dark matter and neutrino physics: dark matter can be non-thermally produced by the decay of the lightest right-handed neutrino after freeze-out, allowing to lower significantly the dark matter mass. We discuss the phenomenology of the non-thermally produced MDM and, taking into account significant Sommerfeld corrections, we find that the dark matter mass must have some specific values in order not to be in conflict with the current bounds from gamma-ray observations.

  4. Neutrino oscillation experiments

    International Nuclear Information System (INIS)

    Camilleri, L.

    1996-01-01

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

  5. Supernovae and neutrinos

    International Nuclear Information System (INIS)

    John F. Beacom

    2002-01-01

    A long-standing problem in supernova physics is how to measure the total energy and temperature of ν μ , ν τ , (bar ν) μ , and (bar ν) τ . While of the highest importance, this is very difficult because these flavors only have neutral-current detector interactions. We propose that neutrino-proton elastic scattering, ν + p → ν + p, can be used for the detection of supernova neutrinos in scintillator detectors. It should be emphasized immediately that the dominant signal is on free protons. Though the proton recoil kinetic energy spectrum is soft, with T p ≅ 2E ν 2 /M p , and the scintillation light output from slow, heavily ionizing protons is quenched, the yield above a realistic threshold is nearly as large as that from (bar ν) e + p → e + + n. In addition, the measured proton spectrum is related to the incident neutrino spectrum. The ability to detect this signal would give detectors like KamLAND and Borexino a crucial and unique role in the quest to detect supernova neutrinos

  6. Long baseline neutrino experiments

    Indian Academy of Sciences (India)

    Atmospheric neutrino experiments (IMB, Kamiokande, Super-Kamiokande (SK)) show that νµ created in cosmic ray interactions with atmospheric nuclei are being converted into ντ but νe created in such interactions are unaffected. SK measure- ment of νµ and νe event rates as functions of zenith angle is the key ...

  7. Baikal - neutrino trap

    International Nuclear Information System (INIS)

    Domogatskij, G.

    1984-01-01

    For recording cosmic neutrinos the installation is considered of a detector in the depths of the Baikal lake with a capacity of up to 10 6 m 3 in the shape of a crystalline lattice with photoelectron multipliers placed in its nodes. (J.B.)

  8. Telecommunication with neutrino beams

    International Nuclear Information System (INIS)

    Saenz, A.W.; Ueberall, H.; Kelly, F.J.; Padgett, D.W.; Seeman, N.

    1977-01-01

    Collimated neutrino beams in the energy range 1 to 100 gigaelectron volts, now available from high-energy proton accelerators, are proposed as a potential means for telecommunication over global distances. Quantitative estimates of the feasibility of this proposal based on a particular detector configuration are presented

  9. Chlorine solar neutrino experiment

    International Nuclear Information System (INIS)

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

    1984-01-01

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

  10. NEUTRINOS: Moriond spotlight

    Energy Technology Data Exchange (ETDEWEB)

    Petcov, S. T.

    1991-05-15

    The regular 'Rencontres de Moriond' meetings in the French Alps, which celebrate their 25th anniversary this year, have a strong tradition of reflecting new trends in physics thinking and January's session on 'Tests of Fundamental Laws in Physics' was no exception. The spotlight this time fell on the neutrino sector, a branch of physics frequently in evolution, if not controversial.

  11. Atmospheric neutrino challenges

    Energy Technology Data Exchange (ETDEWEB)

    Stanev, Todor [Bartol Research Institute, University of Delaware, Newark, DE 19716 (United States)

    2005-08-15

    We briefly review the improvements in the predictions of atmospheric neutrino fluxes since the NOW2000 workshop. In spite of the great progress of the calculational technique the predictions are still not exact because of the uncertainties in the two major sets of input - cosmic ray flux and hadronic interactions on light nuclei.

  12. CERN Neutrino Platform Hardware

    CERN Document Server

    Nelson, Kevin

    2017-01-01

    My summer research was broadly in CERN's neutrino platform hardware efforts. This project had two main components: detector assembly and data analysis work for ICARUS. Specifically, I worked on assembly for the ProtoDUNE project and monitored the safety of ICARUS as it was transported to Fermilab by analyzing the accelerometer data from its move.

  13. Neutrino oscillation experiments

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-11-01

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

  14. Aspects of neutrino astrophysics

    NARCIS (Netherlands)

    de Graaf, Tjeerd

    1969-01-01

    Neutrino-astrofysica lS een onderdeel van de hoge-energieastrofysica, het interdis onderzoekgebied waar de resultaten van de van elementaire deeltjes in verband worden gebracht met 1n de astrofysica. Aan de ene kant kunnen astrofysische bronnen worden voor onderzoekingen naar het van elementaire

  15. Direct neutrino mass measurements

    Energy Technology Data Exchange (ETDEWEB)

    Weinheimer, Christian, E-mail: weinheimer@uni-muenster.de [Westfaelische Wilhelms-Universitaet, Institut fuer Kernphysik (Germany)

    2013-03-15

    Direct neutrino mass experiments are complementary to searches for neutrinoless double {beta}-decay and to analyses of cosmological data. The previous tritium beta decay experiments at Mainz and at Troitsk have achieved upper limits on the neutrino mass of about 2 eV/c{sup 2} . The KATRIN experiment under construction will improve the neutrino mass sensitivity down to 200 meV/c{sup 2} by increasing strongly the statistics and-at the same time-reducing the systematic uncertainties. Huge improvements have been made to operate the system extremely stably and at very low background rate. The latter comprises new methods to reject secondary electrons from the walls as well as to avoid and to eject electrons stored in traps. As an alternative to tritium {beta}-decay experiments cryo-bolometers investigating the endpoint region of {sup 187}Re {beta}-decay or the electron capture of {sup 163}Ho are being developed. This article briefly reviews the current status of the direct neutrino mass measurements.

  16. COLA with massive neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Wright, Bill S.; Winther, Hans A.; Koyama, Kazuya, E-mail: bill.wright@port.ac.uk, E-mail: hans.winther@port.ac.uk, E-mail: kazuya.koyama@port.ac.uk [Institute of Cosmology and Gravitation, University of Portsmouth, Dennis Sciama Building, Burnaby Road, Portsmouth, Hampshire, PO1 3FX (United Kingdom)

    2017-10-01

    The effect of massive neutrinos on the growth of cold dark matter perturbations acts as a scale-dependent Newton's constant and leads to scale-dependent growth factors just as we often find in models of gravity beyond General Relativity. We show how to compute growth factors for ΛCDM and general modified gravity cosmologies combined with massive neutrinos in Lagrangian perturbation theory for use in COLA and extensions thereof. We implement this together with the grid-based massive neutrino method of Brandbyge and Hannestad in MG-PICOLA and compare COLA simulations to full N -body simulations of ΛCDM and f ( R ) gravity with massive neutrinos. Our implementation is computationally cheap if the underlying cosmology already has scale-dependent growth factors and it is shown to be able to produce results that match N -body to percent level accuracy for both the total and CDM matter power-spectra up to k ∼< 1 h /Mpc.

  17. Neutrino oscillation study in the muon neutrino → electron neutrino channel at the Brookhaven accelerator

    International Nuclear Information System (INIS)

    Astier, P.

    1987-09-01

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

  18. The first observations of wide-band interferometers and the spectra of relic gravitons

    CERN Document Server

    Giovannini, Massimo

    2016-01-01

    Stochastic backgrounds of relic gravitons of cosmological origin extend from frequencies of the order of the aHz up to the GHz range. Since the temperature and polarization anisotropies constrain the low frequency normalization of the spectra, in the concordance paradigm the strain amplitude corresponding to the frequency window of wide-band interferometers turns out to be, approximately, nine orders of magnitude smaller than the astounding signal recently reported and attributed to a binary black hole merger. The backgrounds of relic gravitons expected from the early Universe are compared with the stochastic foregrounds stemming from the estimated multiplicity of the astrophysical sources. It is suggested that while the astrophysical foregrounds are likely to dominate between few Hz and 10 kHz, relic gravitons with frequencies exceeding 100 kHz represent a potentially uncontaminated signal for the next generation of high-frequency detectors currently under scrutiny.

  19. Neutrino Oscillation Experiment at JHF

    CERN Multimedia

    2002-01-01

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

  20. New phenomena in neutrino physics

    Energy Technology Data Exchange (ETDEWEB)

    Kopp, Joachim

    2009-04-15

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

  1. New phenomena in neutrino physics

    International Nuclear Information System (INIS)

    Kopp, Joachim

    2009-01-01

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

  2. Radio observations of the double-relic galaxy cluster Abell 1240

    Science.gov (United States)

    Hoang, D. N.; Shimwell, T. W.; van Weeren, R. J.; Intema, H. T.; Röttgering, H. J. A.; Andrade-Santos, F.; Akamatsu, H.; Bonafede, A.; Brunetti, G.; Dawson, W. A.; Golovich, N.; Best, P. N.; Botteon, A.; Brüggen, M.; Cassano, R.; de Gasperin, F.; Hoeft, M.; Stroe, A.; White, G. J.

    2018-05-01

    We present LOFAR 120 - 168 MHz images of the merging galaxy cluster Abell 1240 that hosts double radio relics. In combination with the GMRT 595 - 629 MHz and VLA 2 - 4 GHz data, we characterised the spectral and polarimetric properties of the radio emission. The spectral indices for the relics steepen from their outer edges towards the cluster centre and the electric field vectors are approximately perpendicular to the major axes of the relics. The results are consistent with the picture that these relics trace large-scale shocks propagating outwards during the merger. Assuming diffusive shock acceleration (DSA), we obtain shock Mach numbers of M=2.4 and 2.3 for the northern and southern shocks, respectively. For M≲ 3 shocks, a pre-existing population of mildly relativistic electrons is required to explain the brightness of the relics due to the high (>10 per cent) particle acceleration efficiency required. However, for M≳ 4 shocks the required efficiency is ≳ 1% and ≳ 0.5%, respectively, which is low enough for shock acceleration directly from the thermal pool. We used the fractional polarization to constrain the viewing angle to ≥53 ± 3° and ≥39 ± 5° for the northern and southern shocks, respectively. We found no evidence for diffuse emission in the cluster central region. If the halo spans the entire region between the relics (˜1.8 Mpc) our upper limit on the power is P1.4GHz = (1.4 ± 0.6) × 1023 W Hz-1 which is approximately equal to the anticipated flux from a cluster of this mass. However, if the halo is smaller than this, our constraints on the power imply that the halo is underluminous.

  3. Sterile Neutrinos in Cold Climates

    International Nuclear Information System (INIS)

    Jones, Benjamin J.P.

    2015-01-01

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

  4. Identifying the neutrino mass spectrum from a supernova neutrino burst

    International Nuclear Information System (INIS)

    Dighe, A.S.; Smirnov, A.Yu.

    1999-12-01

    We study the role that the future detection of the neutrino burst from a galactic supernova can play in the reconstruction of the neutrino mass spectrum. We consider all possible 3ν mass and flavor spectra which describe the solar and atmospheric neutrino data. For each of these spectra we find the observable effects of the supernova neutrino conversions both in the matter of the star and the earth. We show that studies of the electron neutrino and antineutrino spectra as well as observations of the neutral current effects from supernova will allow us (i) to identify the solar neutrino solution, (ii) to determine the type of mass hierarchy (normal or inverted) and (iii) to probe the mixing vertical bar U e3 vertical bar 2 to values as low as 10 -4 - 10 -3 . (author)

  5. Probing Neutrino Properties with Long-Baseline Neutrino Beams

    International Nuclear Information System (INIS)

    Marino, Alysia

    2015-01-01

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

  6. High energy neutrinos: sources and fluxes

    Energy Technology Data Exchange (ETDEWEB)

    Stanev, Todor [Bartol Research Institute, Department of Physics and Astronomy, University of Delaware, Newark DE 19716 (United States)

    2006-05-15

    We discuss briefly the potential sources of high energy astrophysical neutrinos and show estimates of the neutrino fluxes that they can produce. A special attention is paid to the connection between the highest energy cosmic rays and astrophysical neutrinos.

  7. Mixing of fourth-generation neutrinos

    International Nuclear Information System (INIS)

    Nussinov, S.

    1987-01-01

    This paper reviews some of the constraints on the mixing of massive decaying neutrinos. Some of the possible implications for neutrino physics of the recent supernova, and in particular the apparent overabundance of neutrino energy, are discussed

  8. Non-unitary neutrino propagation from neutrino decay

    Energy Technology Data Exchange (ETDEWEB)

    Berryman, Jeffrey M., E-mail: jeffreyberryman2012@u.northwestern.edu [Northwestern University, Department of Physics & Astronomy, 2145 Sheridan Road, Evanston, IL 60208 (United States); Gouvêa, André de; Hernández, Daniel [Northwestern University, Department of Physics & Astronomy, 2145 Sheridan Road, Evanston, IL 60208 (United States); Oliveira, Roberto L.N. [Northwestern University, Department of Physics & Astronomy, 2145 Sheridan Road, Evanston, IL 60208 (United States); Instituto de Física Gleb Wataghin Universidade Estadual de Campinas, UNICAMP 13083-970, Campinas, São Paulo (Brazil)

    2015-03-06

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

  9. Non-unitary neutrino propagation from neutrino decay

    International Nuclear Information System (INIS)

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

    2015-01-01

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

  10. Neutrino oscillations and the seesaw origin of neutrino mass

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-07-15

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

  11. When neutrinos attack - the impact of agressive neutrinos in astrophysics.

    Science.gov (United States)

    Kneller, James

    2004-11-01

    Of all the constituents within the standard model of particle physics our understanding of the neutrino has benefited the most from the interaction of astrophysics and `terraphysics'. Much has been learned about the properties of the neutrino from each: experiments here on Earth temper our appreciation of the role that neutrinos play in the cosmos while astrophysics can provide the densities and temperatures in which the neutrinos do more than simply flee. But their reluctance to interact means that it is not until we venture into the most extreme environments of astrophysics that we observe neutrinos pushing back' as hard as they are being pushed'. We review two sites where this occurs: the early Universe and the accretion disk, engines' of gamma ray bursts. Neutrinos play an important role in the evolution of the early Universe with a particular focus upon the electron neutrino in determining the primordial elemental composition via its participation in the most important reaction at that time. Within gamma ray burst accretion disks we again see the electron neutrinos at work in the nuclear reactions and through their function as the coolant' for the disk. Removal of the disk energy, and its deposition into the remnants of the massive star surrounding the disk, may lead to the formation of highly relativistic jets that will later be observed as the burst. We show what has been learned so far about the neutrino and its properties from the study of such environments and discuss where future research is heading.

  12. Matter-neutrino resonance in a multiangle neutrino bulb model

    Science.gov (United States)

    Vlasenko, Alexey; McLaughlin, G. C.

    2018-04-01

    Simulations of neutrino flavor evolution in compact merger environments have shown that neutrino flavor, and hence nucleosynthesis, can be strongly affected by the presence of matter-neutrino resonances (MNRs), where there is a cancelation between the matter and the neutrino potential. Simulations performed thus far follow flavor evolution along a single neutrino trajectory, but self-consistency requires all trajectories to be treated simultaneously, and it has not been known whether MNR phenomena would still occur in multiangle models. In this paper, we present the first fully multi-angle calculations of MNR. We find that familiar MNR phenomena, where neutrinos transform to a greater extent than anti-neutrinos and a feedback mechanism maintains the cancellation between the matter and neutrino potential, still occurs for a subset of angular bins, although the flavor transformation is not as efficient as in the single-angle case. In addition, we find other types of flavor transformation that are not seen in single-angle simulations. These flavor transformation phenomena appear to be robust and are present for a wide range of model parameters, as long as an MNR is present. Although computational constraints currently limit us to models with spherical symmetry, our results suggest that the presence of an MNR generally leads to large-scale neutrino flavor evolution in multiangle systems.

  13. Gauge Trimming of Neutrino Masses

    International Nuclear Information System (INIS)

    Chen, Mu-Chun; de Gouvea, Andre; Dobrescu, Bogdan A.

    2006-01-01

    We show that under a new U(1) gauge symmetry, which is non-anomalous in the presence of one ''right-handed neutrino'' per generation and consistent with the standard model Yukawa couplings, the most general fermion charges are determined in terms of four rational parameters. This generalization of the B-L symmetry with generation-dependent lepton charges leads to neutrino masses induced by operators of high dimensionality. Neutrino masses are thus naturally small without invoking physics at energies above the TeV scale, whether neutrinos are Majorana or Dirac fermions. This ''Leptocratic'' Model predicts the existence of light quasi-sterile neutrinos with consequences for cosmology, and implies that collider experiments may reveal the origin of neutrino masses

  14. Solar neutrino experiments: An update

    International Nuclear Information System (INIS)

    Hahn, R.L.

    1993-01-01

    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 37 Cl Homestake detector, the realtime Kamiokande detector, and the different forms of radiochemical 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

  15. Low Energy Neutrino Cross Sections

    International Nuclear Information System (INIS)

    Zeller, G.P.

    2004-01-01

    Present atmospheric and accelerator based neutrino oscillation experiments operate at low neutrino energies (Ev ∼ 1 GeV) to access the relevant regions of oscillation parameter space. As such, they require precise knowledge of the cross sections for neutrino-nucleon interactions in the sub-to-few GeV range. At these energies, neutrinos predominantly interact via quasi-elastic (QE) or single pion production processes, which historically have not been as well studied as the deep inelastic scattering reactions that dominate at higher energies.Data on low energy neutrino cross sections come mainly from bubble chamber, spark chamber, and emulsion experiments that collected their data decades ago. Despite relatively poor statistics and large neutrino flux uncertainties, these measurements provide an important and necessary constraint on Monte Carlo models in present use. The following sections discuss the current status of QE, resonant single pion, coherent pion, and single kaon production cross section measurements at low energy

  16. Solar neutrino experiments: An update

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, R.L.

    1993-12-31

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

  17. Reactor Neutrino Detection for Non Proliferation with the NUCIFER Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Bouvet, L. [CEA, Centre de Saclay, IRFU, Gif-sur-Yvette, (France); Bouvier, S.; Bui, V. M. [Laboratoire Subatech, Ecole des Mines, Nantes Cedex 3 (France); others, and

    2012-06-15

    Neutrinos are the most abundant matter particles in the Universe. Thoroughly investigated in basic science, the neutrino field is now delivering first applications to the monitoring of nuclear reactors. The neutrinos are emitted in the decay chain of the fission products; therefore measuring their flux provides real-time information, directly related to the fission process occurring in the reactor core. Because of the very weak interaction of neutrinos with matter a neutrino detector can stand outside the core containment vessel and provide a non-intrusive and inherently tamper resistant measurement. After a brief review of the existing data and worldwide projects, we present the NUCIFER experiment. The active part of the detector is a tank filled up with one ton of Gadolinium-doped liquid scintillator. Sixteen photomultiplier tubes, isolated from the liquid by an acrylic buffer, read out the light produced by the interaction of a neutrino with the protons of the liquid. The tank is surrounded by plastic scintillator plates to veto the cosmic rays. Then polyethylene and lead shielding suppress the background coming from external neutrons and gamma rays respectively. The NUCIFER detector has been designed for an optimal compromise between the detection performances and the specifications of operation in a safeguards regime. Its global footprint is 2.8 m x 2.8 m and it can monitor remotely the nuclear power plant thermal power and Plutonium content with very little maintenance on years scale. The experiment is currently installed near the OSIRIS research reactor (70 MWth) at CEA, in Saclay, France. First data are expected by May 2012. This work is done in contact with the IAEA/SGTN division that is currently investigating the potentiality of neutrinos as a novel safeguards tool. A dedicated working group has been created in 2010 to coordinate the simulation effort of various reactor types as well as the development of dedicated detectors and define and eventually

  18. Neutrino oscillations. Theory and experiment

    International Nuclear Information System (INIS)

    Beshtoev, Kh.M.

    2001-01-01

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

  19. Muon colliders and neutrino factories

    Energy Technology Data Exchange (ETDEWEB)

    Geer, S.; /Fermilab

    2010-09-01

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

  20. Sterile neutrinos in the milky way

    DEFF Research Database (Denmark)

    Riemer-Sørensen, Signe; Hansen, Steen Harle; Pedersen, K.

    2006-01-01

    Cosmology: Dark Matter, Elementary Particles, Neutrinos, X-Rays: Diffuse Background Udgivelsesdato: May 30......Cosmology: Dark Matter, Elementary Particles, Neutrinos, X-Rays: Diffuse Background Udgivelsesdato: May 30...

  1. Neutrino clouds and dark matter

    International Nuclear Information System (INIS)

    Goldman, T.; McKellar, B.H.J.; Stephenson, G.J. Jr.

    1996-01-01

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

  2. Sterile neutrinos as dark matter

    International Nuclear Information System (INIS)

    Dodelson, S.; Widrow, L.M.

    1994-01-01

    The simplest model that can accommodate a viable nonbaryonic dark matter candidate is the standard electroweak theory with the addition of right-handed (sterile) neutrinos. We consider a single generation of neutrinos with a Dirac mass μ and a Majorana mass M for the right-handed component. If M much-gt μ (standard hot dark matter corresponds to M=0), then sterile neutrinos are produced via oscillations in the early Universe with energy density independent of M. However, M is crucial in determining the large scale structure of the Universe; for M∼100 eV, sterile neutrinos make an excellent warm dark matter candidate

  3. Double success for neutrino lab

    CERN Multimedia

    2010-01-01

    "The Gran Sasso National Laboratory in Italy is celebrating two key developments in the field of neutrino physics. Number one is the first ever detection, by the OPERA experiement, of possible tau neutrino that has switched its identity from a muon neutrino as it travelled form its origins at CERN in Switzerland to the Italian lab. Number two is the successful start-up of the ICARUS detector, which, like OPERA, is designed to study neutrinos that "oscillate" between types" (0.5 pages)

  4. Neutrino oscillation measurements with reactors

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-11-01

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

  5. Nonstandard neutrino interactions in supernovae

    Science.gov (United States)

    Stapleford, Charles J.; Väänänen, Daavid J.; Kneller, James P.; McLaughlin, Gail C.; Shapiro, Brandon T.

    2016-11-01

    Nonstandard interactions (NSI) of neutrinos with matter can significantly alter neutrino flavor evolution in supernovae with the potential to impact explosion dynamics, nucleosynthesis, and the neutrinos signal. In this paper, we explore, both numerically and analytically, the landscape of neutrino flavor transformation effects in supernovae due to NSI and find a new, heretofore unseen transformation processes can occur. These new transformations can take place with NSI strengths well below current experimental limits. Within a broad swath of NSI parameter space, we observe symmetric and standard matter-neutrino resonances for supernovae neutrinos, a transformation effect previously only seen in compact object merger scenarios; in another region of the parameter space we find the NSI can induce neutrino collective effects in scenarios where none would appear with only the standard case of neutrino oscillation physics; and in a third region the NSI can lead to the disappearance of the high density Mikheyev-Smirnov-Wolfenstein resonance. Using a variety of analytical tools, we are able to describe quantitatively the numerical results allowing us to partition the NSI parameter according to the transformation processes observed. Our results indicate nonstandard interactions of supernova neutrinos provide a sensitive probe of beyond the Standard Model physics complementary to present and future terrestrial experiments.

  6. Neutrino geophysics - a future possibility

    International Nuclear Information System (INIS)

    Kiss, Dezsoe

    1988-01-01

    The history and basic properties of the neutrinos are reviewed. A new idea: neutrino tomography of the Earth interior is discussed in detail. The main contradiction: the high pervasivity of neutrinos, which makes possible the transillumination of the Earth, and the gigantic technical problems of detection caused by the small cross section is pointed out. The proposed possibilities of detection (radiowaves, sound, muons and Cherenkov light emitted by neutrinos) are described. Proposed futuristic technical ideas (mobile muon detectors aboard trucks, floating proton accelerators of 100 km circumference, moving in the ocean) and supposed geological aims (Earth's core, internal density anomalies, quarries of minerals and crude oil) are discussed. (D.Gy.) 5 figs

  7. Magnus approximation in neutrino oscillations

    International Nuclear Information System (INIS)

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

    2011-01-01

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

  8. Supernova neutrino detection in LZ

    Science.gov (United States)

    Khaitan, D.

    2018-02-01

    In the first 10 seconds of a core-collapse supernova, almost all of its progenitor's gravitational potential, O(1053 ergs), is carried away in the form of neutrinos. These neutrinos, with O(10 MeV) kinetic energy, can interact via coherent elastic neutrino-nucleus scattering (CEνNS) depositing O(1 keV) in detectors. In this work we describe the performances of low-background dark matter detectors, such as LUX-ZEPLIN (LZ), optimized for detecting low-energy depositions, in detecting these neutrino interactions. For instance, a 27 Msolar supernova at 10 kpc is expected to produce ~350 neutrino interactions in the 7-tonne liquid xenon active volume of LZ. Based on the LS220 EoS neutrino flux model for a SN, the Noble Element Simulation Technique (NEST), and predicted CEνNS cross-sections for xenon, to study energy deposition and detection of SN neutrinos in LZ. We simulate the response of the LZ data acquisition system (DAQ) and demonstrate its capability and limitations in handling this interaction rate. We present an overview of the LZ detector, focusing on the benefits of liquid xenon for supernova neutrino detection. We discuss energy deposition and detector response simulations and their results. We present an analysis technique to reconstruct the total number of neutrinos and the time of the supernova core bounce.

  9. 50 Years of Neutrino Physics

    International Nuclear Information System (INIS)

    Zralek, M.

    2010-01-01

    Some important topics from history of neutrino physics over the last fifty years are discussed. History of neutrinos is older, at 4 th December 2010 it will be eightieth anniversary of the neutrino birth. In that day W. Pauli wrote the famous letter to participants of the physics conference at Tubingen with the suggestion that '' there could exist in the nuclei electrically neutral particle ''. We will concentrate mostly on the 50 years of neutrino history just to show the long tradition of the Zakopane Theoretical School. (author)

  10. Hunting for a massive neutrino

    CERN Document Server

    AUTHOR|(CDS)2108802

    1997-01-01

    A great effort is devoted by many groups of physicists all over the world to give an answer to the following question: Is the neutrino massive ? This question has profound implications with particle physics, astrophysics and cosmology, in relation to the so-called Dark Matter puzzle. The neutrino oscillation process, in particular, can only occur if the neutrino is massive. An overview of the neutrino mass measurements, of the oscillation formalism and experiments will be given, also in connection with the present experimental programme at CERN with the two experiments CHORUS and NOMAD.

  11. Radiochemical solar neutrino experiments

    International Nuclear Information System (INIS)

    Rich, R.; Spiro, M.

    1993-01-01

    This review covers the three presently running radiochemical solar neutrino experiments, namely the Chlorine, SAGE, and GALLEX experiments. The focus of the review is on a discussion of statistical consistency checks of the available data. The chlorine radiochemical experiment is conceptually simple and shows no strong indication of any statistical anomalies. It still forms the basis of the solar neutrino problem. Each of the two gallium experiments show internal statistical consistency. SAGE's recent preliminary results are consistent with the published GALLEX results. If this convergence is confirmed by a more definitive analysis, this would suggest that the combined result of the two gallium experiments, SAGE and GALLEX, be used for comparisons with theoretical expectations. 5 refs., 15 figs

  12. Caverns for neutrino physicists

    International Nuclear Information System (INIS)

    Duffaut, P.

    2005-01-01

    Since more than 20 years, particle physicists are using underground facilities to catch cosmic neutrinos and to get rid of other parasitic cosmic radiations. The observation of significant numbers of neutrinos requires the use of large volume caverns at important depths. This article presents such existing facilities in the US, France, Italy, UK, Spain, Japan (Kamioka), Russia and India and the different projects in competition for the setting up of a mega-ton detector with a volume of 1 million m 3 of water (DUSEL project in the US, MEMPHYS project in France, Hyperkamiokande in Japan). Several suitable underground spaces are available in these countries (abandoned mines, tunnels) but each has its advantages and drawbacks in terms of rock mechanics, access and seismicity. (J.S.)

  13. Testing the Big Bang: Light elements, neutrinos, dark matter and large-scale structure

    Science.gov (United States)

    Schramm, David N.

    1991-01-01

    Several experimental and observational tests of the standard cosmological model are examined. In particular, a detailed discussion is presented regarding: (1) nucleosynthesis, the light element abundances, and neutrino counting; (2) the dark matter problems; and (3) the formation of galaxies and large-scale structure. Comments are made on the possible implications of the recent solar neutrino experimental results for cosmology. An appendix briefly discusses the 17 keV thing and the cosmological and astrophysical constraints on it.

  14. Electromagnetic properties of neutrinos

    International Nuclear Information System (INIS)

    Ould-Saada, F.

    1996-01-01

    Electromagnetic properties of neutrinos and their implications are discussed, and the experimental situation summarised. Spin precession in solar magnetic fields presents a solution of the solar neutrino problem. A magnetic moment, μ ν , of the order of 10 -11 μ B would be needed. In the simplest extension of the standard model, with no-vanishing neutrino masses, dipole moment interactions are allowed through higher order processes. A neutrino mass of ≅10 eV would give μ ν ≅10 -18 μ B , much smaller than the present experimental upper limit of 2x10 -10 μ B . Although model-dependent, upper bounds on dipole moments from astrophysics and cosmology are 10 to 100 times more stringent. Any values of μ ν , larger than the SM predictions, would then signal the onset of new physics. Among the processes sensitive to the magnetic moment, νe - scattering presents two advantages: it is a pure weak, theoretically well understood process, and the recoil electron can be easily measured. A hypothetical electromagnetic contribution to the cross-section would dominate at low energies. A low background detector, MUNU, being built at the Bugey nuclear reactor is presented.It is based on a gas TPC, surrounded by a scintillator. The threshold on the electron recoil energy can be set very low, around 500 keV, giving the experiment a good sensitivity to the magnetic moment of the ν e , extending down to 2x10 -11 μ B . (author) 15 figs., 5 tabs., 96 refs

  15. The challenge of neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Sutton, Christine

    1995-09-15

    Neutrinos'', Maurice Goldhaber once remarked, ''are remarkable particles: they induce courage in theoreticians and perseverance in experimenters''. They are also no strangers to controversy, for they were in a sense born amidst it, and as recent work on neutrino oscillations demonstrates they continue to fuel debate. This is of course largely to do with the fact that neutrinos have no electric charge and experience only the weak nuclear force, making them supremely difficult to detect. The debates surrounding neutrinos began in the first decades of the 20th century, before the particle had even been thought of. Studies pioneered by Lise Meitner and Otto Hahn suggested that the electrons emitted in beta-decay emerged with discrete energies. In these experiments a spectrometer bent the electrons according to their energy, and a photographic plate detected the electrons emerging through a movable slit, so yielding ''lines'' at various energies. But when James Chadwick used a point counter instead of a photographic plate, he could not find ''the ghost of a line''. Instead, he convinced himself that the energy of the beta-decay electrons varies continuously up to a maximum, with peaks (''lines'') at only a few energies. And he was able to explain how the photographic technique could ''fake'' lines through its great sensitivity to small changes in intensity. The First World War interrupted these investigations, but afterwards arguments between a continuous energy spectrum and discrete lines continued until 1927, when Charles Drummond Ellis and William Wooster at Cambridge published results from a definitive experiment in which they measured the total electron energy in a single decay process. If the electrons always started out with the same energy but lost varying amounts in subsidiary processes to give many lines, as Meitner believed, then the result would equal the maximum at the end of the spectrum.

  16. NEUTRINOS: Moriond spotlight

    International Nuclear Information System (INIS)

    Petcov, S.T.

    1991-01-01

    The regular 'Rencontres de Moriond' meetings in the French Alps, which celebrate their 25th anniversary this year, have a strong tradition of reflecting new trends in physics thinking and January's session on 'Tests of Fundamental Laws in Physics' was no exception. The spotlight this time fell on the neutrino sector, a branch of physics frequently in evolution, if not controversial

  17. Electromagnetic properties of neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Ould-Saada, F [Zurich Univ. (Switzerland). Inst. fuer Physik

    1996-11-01

    Electromagnetic properties of neutrinos and their implications are discussed, and the experimental situation summarised. Spin precession in solar magnetic fields presents a solution of the solar neutrino problem. A magnetic moment, {mu}{sub {nu}}, of the order of 10{sup -11} {mu}{sub B} would be needed. In the simplest extension of the standard model, with no-vanishing neutrino masses, dipole moment interactions are allowed through higher order processes. A neutrino mass of {approx_equal}10 eV would give {mu}{sub {nu}}{approx_equal}10{sup -18} {mu}{sub B}, much smaller than the present experimental upper limit of 2x10{sup -10} {mu}{sub B}. Although model-dependent, upper bounds on dipole moments from astrophysics and cosmology are 10 to 100 times more stringent. Any values of {mu}{sub {nu}}, larger than the SM predictions, would then signal the onset of new physics. Among the processes sensitive to the magnetic moment, {nu}e{sup -} scattering presents two advantages: it is a pure weak, theoretically well understood process, and the recoil electron can be easily measured. A hypothetical electromagnetic contribution to the cross-section would dominate at low energies. A low background detector, MUNU, being built at the Bugey nuclear reactor is presented.It is based on a gas TPC, surrounded by a scintillator. The threshold on the electron recoil energy can be set very low, around 500 keV, giving the experiment a good sensitivity to the magnetic moment of the {nu}{sub e}, extending down to 2x10{sup -11} {mu}{sub B}. (author) 15 figs., 5 tabs., 96 refs.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-01-01

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

  19. Anarchy and neutrino physics

    Energy Technology Data Exchange (ETDEWEB)

    Fortin, Jean-François; Giasson, Nicolas; Marleau, Luc [Département de Physique, de Génie Physique et d’Optique,Université Laval, Québec, QC G1V 0A6 (Canada)

    2017-04-21

    The neutrino sector of a seesaw-extended Standard Model is investigated under the anarchy hypothesis. The previously derived probability density functions for neutrino masses and mixings, which characterize the type I-III seesaw ensemble of N×N complex random matrices, are used to extract information on the relevant physical parameters. For N=2 and N=3, the distributions of the light neutrino masses, as well as the mixing angles and phases, are obtained using numerical integration methods. A systematic comparison with the much simpler type II seesaw ensemble is also performed to point out the fundamental differences between the two ensembles. It is found that the type I-III seesaw ensemble is better suited to accommodate experimental data. Moreover, the results indicate a strong preference for the mass splitting associated to normal hierarchy. However, since all permutations of the singular values are found to be equally probable for a particular mass splitting, predictions regarding the hierarchy of the mass spectrum remains out of reach in the framework of anarchy.

  20. Neutrino physics with SHIP

    CERN Document Server

    van Herwijnen, Eric

    2016-01-01

    SHIP is a new general purpose fixed target facility, whose Technical Proposal has been recently reviewed by the CERN SPS Committee. It recommended that the experiment proceed further to a Comprehensive Design phase. In its initial phase, the 400 GeV proton beam extracted from the SPS will be dumped on a heavy target with the aim of integrating 2×1020 POT (Protons On Target) in 5 years. A dedicated detector, based on a long vacuum tank followed by a spectrometer and particle identification detectors, will allow probing a variety of models with light long-lived exotic particles and masses below O(10) GeV/c 2 . The main focus will be the physics of the so-called Hidden Portals. The sensitivity to Heavy Neutrinos will allow to probe for the first time the mass range between the kaon and the charm meson mass, and a range of couplings for which Baryogenesis and active neutrino masses could also be explained. Another dedicated detector will allow the study of neutrino cross-sections and angular distributions. ντ ...

  1. Neutrino physics at LAMPF

    International Nuclear Information System (INIS)

    Garvey, G.T.

    1989-01-01

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

  2. Convoluted ν-Signals on 114Cd Isotope from Astrophysical and Laboratory Neutrino Sources

    Directory of Open Access Journals (Sweden)

    Vaitsa Tsakstara

    2015-01-01

    Full Text Available At first, we evaluate scattering cross sections of low, and intermediate-energy neutrinos scattered off the 114 Cd isotope, the most abundant Cd isotope present also in the COBRA detector (CdTe and CdZnTe materials which aims to search for double beta decay events and neutrino observations at Gran Sasso laboratory (LNGS. The coherent ν-nucleus channel addressed here is the dominant reaction channel of the neutral current ν-nucleus scattering. Our ν-nucleus cross sections (calculated with a refinement of the quasiparticle random-phase approximation, QRPA refer to the gs→gs transitions for ν-energies εν≤100 MeV. Subsequently, simulated ν-signals on 114 Cd isotope are derived. Towards this purpose, the required folded cross section comes out of simulation techniques by employing several low, and intermediate-energy neutrino distributions of the astrophysical ν-sources, like the solar, supernova, and Earth neutrinos, as well as the laboratory neutrinos, the reactor neutrinos, the pion-muon stopped neutrinos, and the β-beam neutrinos.

  3. Relating the baryon asymmetry to the thermal relic dark matter density

    International Nuclear Information System (INIS)

    McDonald, John

    2011-01-01

    We present a generic framework, baryomorphosis, which modifies the baryon asymmetry to be naturally of the order of a typical thermal relic weakly interacting massive particle (WIMP) density. We consider a simple scalar-based model to show how this is possible. This model introduces a sector in which a large initial baryon asymmetry is injected into particles ('annihilons'), φ B , φ-circumflex B , of mass ∼100 GeV-1 TeV. φ B φ-circumflex B annihilations convert the initial φ B , φ-circumflex B asymmetry to a final asymmetry with a thermal relic WIMP-like density. This subsequently decays to a conventional baryon asymmetry whose magnitude is naturally related to the density of thermal relic WIMP dark matter. In this way the two coincidences of baryons and dark matter, i.e. why their densities are similar to each other and why they are both similar to a WIMP thermal relic density (the 'WIMP miracle'), may be understood. The model may be tested by the production of annihilons at colliders.

  4. The Variable and Changing Status of Performance Art Relics and Artifacts in Museum Collections

    DEFF Research Database (Denmark)

    Cone, Louise

    2017-01-01

    The status of an artwork in a museum collection is variable and contingent upon factors and parameters that are specific not only to the logic of the museum world but also to factors extrinsic to the museum. In particular older performance art 'relics' are subject to contextual interpretations...

  5. a Method of 3d Measurement and Reconstruction for Cultural Relics in Museums

    Science.gov (United States)

    Zheng, S.; Zhou, Y.; Huang, R.; Zhou, L.; Xu, X.; Wang, C.

    2012-07-01

    Three-dimensional measurement and reconstruction during conservation and restoration of cultural relics have become an essential part of a modem museum regular work. Although many kinds of methods including laser scanning, computer vision and close-range photogrammetry have been put forward, but problems still exist, such as contradiction between cost and good result, time and fine effect. Aimed at these problems, this paper proposed a structure-light based method for 3D measurement and reconstruction of cultural relics in museums. Firstly, based on structure-light principle, digitalization hardware has been built and with its help, dense point cloud of cultural relics' surface can be easily acquired. To produce accurate 3D geometry model from point cloud data, multi processing algorithms have been developed and corresponding software has been implemented whose functions include blunder detection and removal, point cloud alignment and merge, 3D mesh construction and simplification. Finally, high-resolution images are captured and the alignment of these images and 3D geometry model is conducted and realistic, accurate 3D model is constructed. Based on such method, a complete system including hardware and software are built. Multi-kinds of cultural relics have been used to test this method and results prove its own feature such as high efficiency, high accuracy, easy operation and so on.

  6. Relics of short distance effects for the neutron electric dipole moment

    International Nuclear Information System (INIS)

    Eeg, J.O.

    1982-12-01

    The Feynman diagrams which dominate the estimates of the electric dipole moment of the neutron with Kobayashi-Maskawa CP violation are considered. The extracted long distance contributions and the relics of short distance contributions are shown to be complementary and of the same magnitude, resulting in mod(Dsub(n)/e) approximately = (10 - 31 - 10 - 30 ) cm. (Auth.)

  7. Ultra-cold WIMPs relics of non-standard pre-BBN cosmologies

    CERN Document Server

    Gelmini, Graciela B

    2008-01-01

    We point out that in scenarios in which the Universe evolves in a non-standard manner during and after the kinetic decoupling of weakly interacting massive particles (WIMPs), these relics can be much colder than in standard cosmological scenarios (i.e. can be ultra-cold), possibly leading to the formation of smaller first objects in hierarchical structure formation scenarios.

  8. New neutrino oscillation results from NOVA

    CERN Multimedia

    CERN. Geneva

    2018-01-01

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

  9. Flipped Heavy Neutrinos from the Solar Neutrino Problem to Baryogenesis

    CERN Document Server

    Ellis, Jonathan Richard; Olive, Keith A

    1993-01-01

    We discuss baryogenesis using the flipped $SU(5)$ model for lepton mass matrices. We show that the generalized see-saw mechanism in this model can not only provide MSW neutrino mixing suitable for solving the solar neutrino problem, and supply a hot dark matter candidate ($\

  10. JUNO. Determination of the neutrino mass hierarchy using reactor neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Wonsak, Bjoern [Hamburg University, Inst. Exp. Phys., Hamburg (Germany)

    2015-07-01

    The Jiangmen Underground Neutrino Observatory (JUNO) is a medium-baseline reactor neutrino experiment located in China. Its aim is to determine the neutrino mass hierarchy at more than 3 sigma significance after six years of data taking by using a 20kt liquid scintillator detector. To achieve this goal, an energy resolution of less than 3%/√(E) is necessary, creating strict requirements on the detector design and the liquid scintillator. Moreover, JUNO will be the only experiment in the near future able to measure the solar mixing parameters with a precision of better than 1%. This is at the same level as our current knowledge on flavour mixing in the quark sector, marking an important milestone of neutrino physics. In addition, supernova neutrinos, geo-neutrinos, sterile neutrinos as well as solar and atmospheric neutrinos can be studied. JUNO was approved in 2013 and the construction of the underground facility started early this year. In this talk the status of the experiment and its prospects is discussed.

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

    Science.gov (United States)

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

    2004-06-01

    The Homestake result is about ˜2σ lower than the Ar-production rate, QAr, predicted by the large mixing angle (LMA) Mikheyev-Smirnov-Wolfenstein solution of the solar neutrino problem. Also there is no apparent upturn of the energy spectrum (R≡Nobs/NSSM) at low energies in SNO and Super-Kamiokande. Both these facts can be explained if a light, Δm201˜(0.2 2)×10-5 eV2, sterile neutrino exists which mixes very weakly with active neutrinos: sin2 2α˜(10-5 10-3). We perform both the analytical and numerical study of the conversion effects in the system of two active neutrinos with the LMA parameters and one weakly mixed sterile neutrino. The presence of sterile neutrino leads to a dip in the survival probability in the intermediate energy range E=(0.5 5) MeV thus suppressing the Be, or/and pep, CNO, as well as B electron neutrino fluxes. Apart from diminishing QAr it leads to decrease of the Ge-production rate and may lead to the decrease of the BOREXINO signal as well as the CC/NC ratio at SNO. Future studies of the solar neutrinos by SNO, SK, BOREXINO, and KamLAND as well as by the new low energy experiments will allow us to check this possibility.

  12. Looking for Cosmic Neutrino Background

    Directory of Open Access Journals (Sweden)

    Chiaki eYanagisawa

    2014-06-01

    Full Text Available Since the discovery of neutrino oscillation in atmospheric neutrinos by the Super-Kamiokande experiment in 1998, study of neutrinos has been one of exciting fields in high-energy physics. All the mixing angles were measured. Quests for 1 measurements of the remaining parameters, the lightest neutrino mass, the CP violating phase(s, and the sign of mass splitting between the mass eigenstates m3 and m1, and 2 better measurements to determine whether the mixing angle theta23 is less than pi/4, are in progress in a well-controlled manner. Determining the nature of neutrinos, whether they are Dirac or Majorana particles is also in progress with continuous improvement. On the other hand, although the ideas of detecting cosmic neutrino background have been discussed since 1960s, there has not been a serious concerted effort to achieve this goal. One of the reasons is that it is extremely difficult to detect such low energy neutrinos from the Big Bang. While there has been tremendous accumulation of information on Cosmic Microwave Background since its discovery in 1965, there is no direct evidence for Cosmic Neutrino Background. The importance of detecting Cosmic Neutrino Background is that, although detailed studies of Big Bang Nucleosynthesis and Cosmic Microwave Background give information of the early Universe at ~a few minutes old and ~300 k years old, respectively, observation of Cosmic Neutrino Background allows us to study the early Universe at $sim$ 1 sec old. This article reviews progress made in the past 50 years on detection methods of Cosmic Neutrino Background.

  13. On the absence of radio haloes in clusters with double relics

    Science.gov (United States)

    Bonafede, A.; Cassano, R.; Brüggen, M.; Ogrean, G. A.; Riseley, C. J.; Cuciti, V.; de Gasperin, F.; Golovich, N.; Kale, R.; Venturi, T.; van Weeren, R. J.; Wik, D. R.; Wittman, D.

    2017-09-01

    Pairs of radio relics are believed to form during cluster mergers, and are best observed when the merger occurs in the plane of the sky. Mergers can also produce radio haloes, through complex processes likely linked to turbulent re-acceleration of cosmic ray electrons. However, only some clusters with double relics also show a radio halo. Here, we present a novel method to derive upper limits on the radio halo emission, and analyse archival X-ray Chandra data, as well as galaxy velocity dispersions and lensing data, in order to understand the key parameter that switches on radio halo emission. We place upper limits on the halo power below the P1.4 GHz-M500 correlation for some clusters, confirming that clusters with double relics have different radio properties. Computing X-ray morphological indicators, we find that clusters with double relics are associated with the most disturbed clusters. We also investigate the role of different mass-ratios and time-since-merger. Data do not indicate that the merger mass-ratio has an impact on the presence or absence of radio haloes (the null hypothesis that the clusters belong to the same group cannot be rejected). However, the data suggest that the absence of radio haloes could be associated with early and late mergers, but the sample is too small to perform a statistical test. Our study is limited by the small number of clusters with double relics. Future surveys with LOFAR, ASKAP, MeerKat and SKA will provide larger samples to better address this issue.

  14. Freeze-in production of sterile neutrino dark matter in U(1){sub B−L} model

    Energy Technology Data Exchange (ETDEWEB)

    Biswas, Anirban; Gupta, Aritra [Harish-Chandra Research Institute,Chhatnag Road, Jhunsi, Allahabad 211 019 (India)

    2016-09-27

    With the advent of new and more sensitive direct detection experiments, scope for a thermal WIMP explanation of dark matter (DM) has become extremely constricted. The non-observation of thermal WIMP in these experiments has put a strong upper bound on WIMP-nucleon scattering cross section and within a few years it is likely to overlap with the coherent neutrino-nucleon cross section. Hence in all probability, DM may have some non-thermal origin. In this work we explore in detail this possibility of a non-thermal sterile neutrino DM within the framework of U(1){sub B−L} model. The U(1){sub B−L} model on the other hand is a well-motivated and minimal way of extending the standard model so that it can explain the neutrino masses via Type-I see-saw mechanism. We have shown, besides explaining the neutrino mass, it can also accommodate a non-thermal sterile neutrino DM with correct relic density. In contrast with the existing literature, we have found that W{sup ±} decay can also be a dominant production mode of the sterile neutrino DM. To obtain the comoving number density of dark matter, we have solved here a coupled set of Boltzmann equations considering all possible decay as well as annihilation production modes of the sterile neutrino dark matter. The framework developed here though has been done for a U(1){sub B−L} model, can be applied quite generally for any models with an extra neutral gauge boson and a fermionic non-thermal dark matter.

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

    Science.gov (United States)

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

    2016-06-01

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

  16. Radiative neutrino mass model with degenerate right-handed neutrinos

    International Nuclear Information System (INIS)

    Kashiwase, Shoichi; Suematsu, Daijiro

    2016-01-01

    The radiative neutrino mass model can relate neutrino masses and dark matter at a TeV scale. If we apply this model to thermal leptogenesis, we need to consider resonant leptogenesis at that scale. It requires both finely degenerate masses for the right-handed neutrinos and a tiny neutrino Yukawa coupling. We propose an extension of the model with a U(1) gauge symmetry, in which these conditions are shown to be simultaneously realized through a TeV scale symmetry breaking. Moreover, this extension can bring about a small quartic scalar coupling between the Higgs doublet scalar and an inert doublet scalar which characterizes the radiative neutrino mass generation. It also is the origin of the Z 2 symmetry which guarantees the stability of dark matter. Several assumptions which are independently supposed in the original model are closely connected through this extension. (orig.)

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

    International Nuclear Information System (INIS)

    Takahashi, Keitaro; Sato, Katsuhiko

    2003-01-01

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

  18. Identifying the neutrino mass hierarchy with supernova neutrinos

    International Nuclear Information System (INIS)

    Tomas, Ricard

    2006-01-01

    We review how a high-statistics observation of the neutrino signal from a future galactic core-collapse supernova (SN) may be used to discriminate between different neutrino mixing scenarios. We discuss two complementary methods that allow for the positive identification of the mass hierarchy without knowledge of the emitted neutrino fluxes, provided that the 13-mixing angle is large, sin 2 θ 13 -5 . These two approaches are the observation of modulations in the neutrino spectra by Earth matter effects or by the passage of shock waves through the SN envelope. If the value of the 13-mixing angle is unknown, using additionally the information encoded in the prompt neutronization ν e burst-a robust feature found in all modern SN simulations-can be sufficient to fix both the neutrino hierarchy and to decide whether θ 13 is 'small' or 'large'

  19. Sterile neutrino constraints from cosmology

    DEFF Research Database (Denmark)

    Hamann, Jan; Hannestad, Steen; Raffelt, Georg G.

    2012-01-01

    The presence of light particles beyond the standard model's three neutrino species can profoundly impact the physics of decoupling and primordial nucleosynthesis. I review the observational signatures of extra light species, present constraints from recent data, and discuss the implications of po...... of possible sterile neutrinos with O(eV)-masses for cosmology....

  20. CERN neutrino project on target

    CERN Multimedia

    2005-01-01

    Scientists at CERN announced the completion of the target assembly for the CERN neutrinos to Gran Sasso project, CNGS. On schedule for start-up in May 2006, CNGS will send a beam of neutrinos through the Earth to the Gran Sasso laboratory 730 km away in Italy in a bid to unravel the mysteries of nature's most elusive particles (½ page)