WorldWideScience

Sample records for antineutrinos

  1. Antineutrino Monitoring of Thorium Reactors

    CERN Document Server

    Akindele, Oluwatomi A; Norman, Eric B

    2015-01-01

    Various groups have demonstrated that antineutrino monitoring can be successful in assessing the plutonium content in water-cooled nuclear reactors for nonproliferation applications. New reactor designs and concepts incorporate nontraditional fuels types and chemistry. Understanding how these properties affect the antineutrino emission from a reactor can extend the applicability of antineutrino monitoring.Thorium molten salt reactors (MSR) breed U-233, that if diverted constitute an IAEA direct use material. The antineutrino spectrum from the fission of U-233 has been determined, the feasibility of detecting the diversion of a significant quantity, 8 kg of U-233, within the IAEA timeliness goal of 30 days has been evaluated. The antineutrino emission from a thorium reactor operating under normal conditions is compared to a diversion scenario at a 25 meter standoff by evaluating the daily antineutrino count rate and the energy spectrum of the detected antineutrinos. It was found that the diversion of a signifi...

  2. Antineutrino oscillation study in the muon antineutrino → electron antineutrino channel at the Brookhaven accelerator

    International Nuclear Information System (INIS)

    This thesis is devoted to the E816 experiment which looked for (anti)neutrino oscillations. This experiment was performed in the neutrino beam of the Brookhaven AGS during spring 1986. Following a short recall of the theoretical and experimental status, the beam line and the apparatus are described. The analysis is exposed in details with a special emphasis on final states including at least one electromagnetic shower and one prong. Preliminary results have been obtained and show an excess of 23 ±8.7±14.6 events interpreted as charged current antineutrino electron interactions. In terms of a limit we obtain for the probability P(antineutrino muon → antineutrino electron): P<4.4% (95% C.L.)

  3. KamLAND and Solar Antineutrino Spectrum

    CERN Document Server

    Chauhan, B C; Torrente-Lujan, E; Chauhan, Bhag C.; Pulido, Joao

    2004-01-01

    We use the recent KamLAND observations to predict the solar antineutrino spectrum at some confidence limits. We find that a scaling of the antineutrino probability with respect to the magnetic field profile --in the sense that the same probability function can be reproduced by any profile with a suitable peak field value-- can be utilised to obtain a general shape of the solar antineutrino spectrum. This scaling and the upper bound on the solar antineutrino event rate, that can be derived from the data, lead to: 1) an upper bound on the solar antineutrino flux, 2) the prediction of their energy spectrum, as the normalisation of the spectrum can be obtained from the total number of antineutrino events recorded in the experiment. We get $\\phi_{\\bar\

  4. AGM2015: Antineutrino Global Map 2015

    CERN Document Server

    Usman, Shawn M; Dye, Stephen T; McDonough, William F; Learned, John G

    2015-01-01

    Every second greater than $10^{25}$ antineutrinos radiate to space from Earth, shining like a faint antineutrino star. Underground antineutrino detectors have revealed the rapidly decaying fission products inside nuclear reactors, verified the long-lived radioactivity inside our planet, and informed sensitive experiments for probing fundamental physics. Mapping the anisotropic antineutrino flux and energy spectrum advance geoscience by defining the amount and distribution of radioactive power within Earth while critically evaluating competing compositional models of the planet. We present the Antineutrino Global Map 2015 (AGM2015), an experimentally informed model of Earth's surface antineutrino flux over the 0 to 11 MeV energy spectrum, along with an assessment of systematic errors. The open source AGM2015 provides fundamental predictions for experiments, assists in strategic detector placement to determine neutrino mass hierarchy, and aids in identifying undeclared nuclear reactors. We use cosmochemically a...

  5. AGM2015: Antineutrino Global Map 2015

    Science.gov (United States)

    Usman, S. M.; Jocher, G. R.; Dye, S. T.; McDonough, W. F.; Learned, J. G.

    2015-09-01

    Every second greater than 1025 antineutrinos radiate to space from Earth, shining like a faint antineutrino star. Underground antineutrino detectors have revealed the rapidly decaying fission products inside nuclear reactors, verified the long-lived radioactivity inside our planet, and informed sensitive experiments for probing fundamental physics. Mapping the anisotropic antineutrino flux and energy spectrum advance geoscience by defining the amount and distribution of radioactive power within Earth while critically evaluating competing compositional models of the planet. We present the Antineutrino Global Map 2015 (AGM2015), an experimentally informed model of Earth’s surface antineutrino flux over the 0 to 11 MeV energy spectrum, along with an assessment of systematic errors. The open source AGM2015 provides fundamental predictions for experiments, assists in strategic detector placement to determine neutrino mass hierarchy, and aids in identifying undeclared nuclear reactors. We use cosmochemically and seismologically informed models of the radiogenic lithosphere/mantle combined with the estimated antineutrino flux, as measured by KamLAND and Borexino, to determine the Earth’s total antineutrino luminosity at . We find a dominant flux of geo-neutrinos, predict sub-equal crust and mantle contributions, with ~1% of the total flux from man-made nuclear reactors.

  6. Antineutrino Oscillations in the Atmospheric Sector

    Energy Technology Data Exchange (ETDEWEB)

    Himmel, Alexander I. [California Inst. of Technology (CalTech), Pasadena, CA (United States)

    2011-05-01

    This thesis presents measurements of the oscillations of muon antineutrinos in the atmospheric sector, where world knowledge of antineutrino oscillations lags well behind the knowledge of neutrinos, as well as a search for vμ → $\\bar{v}$μ transitions. Differences between neutrino and antineutrino oscillations could be a sign of physics beyond the Standard Model, including non-standard matter interactions or the violation of CPT symmetry. These measurements leverage the sign-selecting capabilities of the magnetized steel-scintillator MINOS detectors to analyze antineutrinos from the NuMI beam, both when it is in neutrino-mode and when it is in antineutrino-mode. Antineutrino oscillations are observed at |Δ$\\bar{m}$atm 2| = (3.36-0.40+0.46(stat) ± 0.06(syst)) x 10-3 eV2 and sin2(2$\\bar{θ}$23) = 0.860-0.12+0.11(stat) ± 0.01(syst). The oscillation parameters measured for antineutrinos and those measured by MINOS for neutrinos differ by a large enough margin that the chance of obtaining two values as discrepant as those observed is only 2%, assuming the two measurements arise from the same underlying mechanism, with the same parameter values. No evidence is seen for neutrino-to-antineutrino transitions.

  7. Antineutrino Oscillations in the Atmospheric Sector

    Energy Technology Data Exchange (ETDEWEB)

    Himmel, Alexander I.; /Caltech

    2011-05-01

    This thesis presents measurements of the oscillations of muon antineutrinos in the atmospheric sector, where world knowledge of antineutrino oscillations lags well behind the knowledge of neutrinos, as well as a search for {nu}{sub {mu}} {yields} {bar {nu}}{sub {mu}} transitions. Differences between neutrino and antineutrino oscillations could be a sign of physics beyond the Standard Model, including non-standard matter interactions or the violation of CPT symmetry. These measurements leverage the sign-selecting capabilities of the magnetized steel-scintillator MINOS detectors to analyze antineutrinos from the NuMI beam, both when it is in neutrino-mode and when it is in antineutrino-mode. Antineutrino oscillations are observed at |{Delta}{bar m}{sub atm}{sup 2}| = (3.36{sub -0.40}{sup +0.46}(stat) {+-} 0.06(syst)) x 10{sup -3} eV{sup 2} and sin{sup 2}(2{bar {theta}}{sub 23}) = 0.860{sub -0.12}{sup +0.11}(stat) {+-} 0.01(syst). The oscillation parameters measured for antineutrinos and those measured by MINOS for neutrinos differ by a large enough margin that the chance of obtaining two values as discrepant as those observed is only 2%, assuming the two measurements arise from the same underlying mechanism, with the same parameter values. No evidence is seen for neutrino-to-antineutrino transitions.

  8. Reactor Antineutrinos Signal all over the world

    CERN Document Server

    Ricci, B; Baldoncini, M; Esposito, J; Ludhova, L; Zavatarelli, S

    2014-01-01

    We present an updated estimate of reactor antineutrino signal all over the world, with particular attention to the sites proposed for existing and future geo-neutrino experiment. In our calculation we take into account the most updated data on Thermal Power for each nuclear plant, on reactor antineutrino spectra and on three neutrino oscillation mechanism.

  9. Antineutrino Geophysics with Liquid Scintillator Detectors

    CERN Document Server

    Rothschild, C G; Calaprice, F P; Rothschild, Casey G.; Chen, Mark C.; Calaprice, Frank P.

    1997-01-01

    Detecting the antineutrinos emitted by the decay of radioactive elements in the mantle and crust could provide a direct measurement of the total abundance of uranium and thorium in the Earth. In calculating the antineutrino flux at specific sites, the local geology of the crust and the background from the world's nuclear power reactors are important considerations. Employing a global crustal map, with type and thickness data, and using recent estimates of the uranium and thorium distribution in the Earth, we calculate the antineutrino event rate for two new neutrino detectors. We show that spectral features allow terrestrial antineutrino events to be identified above reactor antineutrino backgrounds and that the uranium and thorium contributions can be separately determined.

  10. Is Deuterium Nuclear Fusion Catalyzed by Antineutrinos?

    Science.gov (United States)

    Shomer, Isaac

    2010-02-01

    The hypothesis of Fischbach and Jenkins that neutrinos emitted from the sun accelerate radioactive decay is noted. It is thought that neutrinos accelerate beta decay by reacting with neutron-rich nuclides to form a beta particle and a daughter product, with no antineutrino emitted. Conversely, it is proposed that antineutrinos can react with proton-rich nuclides to cause positron decay, with no neutrino emitted. It is also proposed that the nuclear fusion of the hydrogen bomb is triggered not only by the energy of the igniting fission bomb, but by the antineutrinos created by the rapid beta decay of the daughter products in the fission process. The contemplated mechanism for antineutrino initiated fusion is the following: 1. The antineutrinos from the fission daughter products cause positron decay of deuterium by the process outlined above. 2. In a later fusion step, these positrons subsequently react with neutrons in deuterium to create antineutrinos. Electrons are unavailable to annihilate positrons in the plasma of the hydrogen bomb. 3. These antineutrinos thereafter react with more deuterium to form positrons, thereby propagating a chain reaction. )

  11. Web Application for Modeling Global Antineutrinos

    CERN Document Server

    Barna, Andrew

    2015-01-01

    Electron antineutrinos stream freely from rapidly decaying fission products within nuclear reactors and from long-lived radioactivity within Earth. Those with energy greater than 1.8 MeV are regularly observed by several kiloton-scale underground detectors. These observations estimate the amount of terrestrial radiogenic heating, monitor the operation of nuclear reactors, and measure the fundamental properties of neutrinos. The analysis of antineutrino observations at operating detectors or the planning of projects with new detectors requires information on the expected signal and background rates. We present a web application for modeling global antineutrino energy spectra and detection rates for any surface location. Antineutrino sources include all registered nuclear reactors as well as the crust and mantle of Earth. Visitors to the website may model the location and power of a hypothetical nuclear reactor, copy energy spectra, and analyze the significance of a selected signal relative to background.

  12. Daya Bay Antineutrino Detector Gas System

    CERN Document Server

    Band, H R; Chu, M-C; Heeger, K M; Kwok, M W; Shih, K; Wise, T; Xiao, Q

    2012-01-01

    The Daya Bay Antineutrino Detector gas system is designed to protect the liquid scintillator targets of the antineutrino detectors against degradation and contamination from exposure to ambient laboratory air. The gas system is also used to monitor the leak tightness of the antineutrino detector assembly. The cover gas system constantly flushes the gas volumes above the liquid scintillator with dry nitrogen to minimize oxidation of the scintillator over the five year lifetime of the experiment. This constant flush also prevents the infiltration of radon or other contaminants into these detecting liquids keeping the internal backgrounds low. Since the Daya Bay antineutrino detectors are immersed in the large water pools of the muon veto system, other gas volumes are needed to protect vital detector cables or gas lines. These volumes are also purged with dry gas. Return gas is monitored for oxygen content and humidity to provide early warning of potentially damaging leaks. The design and performance of the Daya...

  13. Reference worldwide model for antineutrinos from reactors

    OpenAIRE

    Baldoncini, Marica; Callegari, Ivan; Fiorentini, Giovanni; Mantovani, Fabio; Ricci, Barbara; Strati, Virginia; Xhixha, Gerti

    2014-01-01

    Antineutrinos produced at nuclear reactors constitute a severe source of background for the detection of geoneutrinos, which bring to the Earth's surface information about natural radioactivity in the whole planet. In this framework we provide a reference worldwide model for antineutrinos from reactors, in view of reactors operational records yearly published by the International Atomic Energy Agency (IAEA). We evaluate the expected signal from commercial reactors for ongoing (KamLAND and Bor...

  14. Antineutrino monitoring of spent nuclear fuel

    OpenAIRE

    Brdar, Vedran; Huber, Patrick; Kopp, Joachim

    2016-01-01

    Military and civilian applications of nuclear energy have left a significant amount of spent nuclear fuel over the past 70 years. Currently, in many countries world wide, the use of nuclear energy is on the rise. Therefore, the management of highly radioactive nuclear waste is a pressing issue. In this letter, we explore antineutrino detectors as a tool for monitoring and safeguarding nuclear waste material. We compute the flux and spectrum of antineutrinos emitted by spent nuclear fuel eleme...

  15. Antineutrino Geophysics with Liquid Scintillator Detectors

    OpenAIRE

    Rothschild, Casey G.; Chen, Mark C.; Calaprice, Frank P.

    1997-01-01

    Detecting the antineutrinos emitted by the decay of radioactive elements in the mantle and crust could provide a direct measurement of the total abundance of uranium and thorium in the Earth. In calculating the antineutrino flux at specific sites, the local geology of the crust and the background from the world's nuclear power reactors are important considerations. Employing a global crustal map, with type and thickness data, and using recent estimates of the uranium and thorium distribution ...

  16. Neutrino Data and Neutrino-Antineutrino Transition

    CERN Document Server

    Alexeyev, E N

    2005-01-01

    A problem, whether a neutrino-antineutrino transition could be responsible for the muon neutrino deficit found in underground experiments (Super-Kamiokande, MACRO, Soudan 2) and in the accelerator long-baseline K2K experiment, is discussed in this paper. The intention of the work is not consideration of concrete models for muon neutrino-antineutrino transition but a desire to attract an attention to another possibility of understanding the nature of the measured muon neutrino deficit in neutrino experiments.

  17. Antineutrino monitoring of spent nuclear fuel

    CERN Document Server

    Brdar, Vedran; Kopp, Joachim

    2016-01-01

    Military and civilian applications of nuclear energy have left a significant amount of spent nuclear fuel over the past 70 years. Currently, in many countries world wide, the use of nuclear energy is on the rise. Therefore, the management of highly radioactive nuclear waste is a pressing issue. In this letter, we explore antineutrino detectors as a tool for monitoring and safeguarding nuclear waste material. We compute the flux and spectrum of antineutrinos emitted by spent nuclear fuel elements as a function of time, and we illustrate the usefulness of antineutrino detectors in several benchmark scenarios. In particular, we demonstrate how a measurement of the antineutrino flux can help to re-verify the contents of a dry storage cask in case the monitoring chain by conventional means gets disrupted. We then comment on the usefulness of antineutrino detectors at long-term storage facilities such as Yucca mountain. Finally, we put forward antineutrino detection as a tool in locating underground "hot spots" in ...

  18. A Precise Measurement of Reactor Antineutrino at RENO

    Science.gov (United States)

    Jang, J. S.

    2014-06-01

    RENO is the reactor experiment to measure the neutrino mixing angle θ1 3 by observing the disappearance of the reactor antineutrino. Antineutrinos from six reactors at Yonggwang Nuclear Power Plant in Korea, are detected and compared by two identical detectors located at 294 m and 1383 m, respectively, from the center of the reactor array. The far (near) detector observes 73 (780) electron antineutrino candidate events per day after background subtraction with the precise measurement of reactor antineutrino flux. In this paper, an updated result is presented about the energy spectra of antineutrino signals in RENO detectors. A precise measurement of reactor antineutrino flux is also presented in comparison with expectations.

  19. A Precise Measurement of Reactor Antineutrino at RENO

    International Nuclear Information System (INIS)

    RENO is the reactor experiment to measure the neutrino mixing angle θ13 by observing the disappearance of the reactor antineutrino. Antineutrinos from six reactors at Yonggwang Nuclear Power Plant in Korea, are detected and compared by two identical detectors located at 294 m and 1383 m, respectively, from the center of the reactor array. The far (near) detector observes 73 (780) electron antineutrino candidate events per day after background subtraction with the precise measurement of reactor antineutrino flux. In this paper, an updated result is presented about the energy spectra of antineutrino signals in RENO detectors. A precise measurement of reactor antineutrino flux is also presented in comparison with expectations

  20. Workshop applied antineutrino physics 2007

    International Nuclear Information System (INIS)

    The 'Applied Antineutrino Physics 2007' workshop is the fourth international meeting devoted to the opening of the neutrino physics to more applied fields, such as geophysics and geochemistry, nuclear industry, as well as the nonproliferation. This meeting highlights the world efforts already engaged to exploit the single characteristics of the neutrinos for the control of the production of plutonium in the civil nuclear power reactor. The potential industrial application of the measurement of the thermal power of the nuclear plants by the neutrinos is also approached. earth neutrinos were for the first time highlighted in 2002 by the KamLAND experiment. Several international efforts are currently underway to use earth neutrinos to reveal the interior of the Earth. This meeting is an opportunity to adapt the efforts of detection to the real needs of geophysicists and geochemists (sources of radiogenic heat, potassium in the court, feathers.) Finally more futuristic topics such as the detection of nuclear explosions, of low powers, are also discussed. This document gathers only the slides of the presentations

  1. Workshop applied antineutrino physics 2007

    Energy Technology Data Exchange (ETDEWEB)

    Akiri, T.; Andrieu, B.; Anjos, J.; Argyriades, J.; Barouch, G.; Bernstein, A.; Bersillon, O.; Besida, O.; Bowden, N.; Cabrera, A.; Calmet, D.; Collar, J.; Cribier, M.; Kerret, H. de; Meijer, R. de; Dudziak, F.; Enomoto, S.; Fallot, M.; Fioni, G.; Fiorentini, G.; Gale, Ph.; Georgadze, A.; Giot, L.; Gonin, M.; Guillon, B.; Henson, C.; Jonkmans, G.; Kanamaru, S.; Kawasaki, T.; Kornoukhov, V.; Lasserre, Th.; Learned, J.G.; Lefebvre, J.; Letourneau, A.; Lhillier, D.; Lindner, M.; Lund, J.; Mantovani, F.; Mcdonough, B.; Mention, G.; Monteith, A.; Motta, D.; Mueller, Th.; Oberauer, L.; Obolensky, M.; Odrzywolek, A.; Petcov, S.; Porta, A.; Queval, R.; Reinhold, B.; Reyna, D.; Ridikas, D.; Sadler, L.; Schoenert, St.; Sida, J.L.; Sinev, V.; Suekane, F.; Suvorov, Y.; Svoboda, R.; Tang, A.; Tolich, N.; Tolich, K.; Vanka, S.; Vignaud, D.; Volpe, Ch.; Wong, H

    2007-07-01

    The 'Applied Antineutrino Physics 2007' workshop is the fourth international meeting devoted to the opening of the neutrino physics to more applied fields, such as geophysics and geochemistry, nuclear industry, as well as the nonproliferation. This meeting highlights the world efforts already engaged to exploit the single characteristics of the neutrinos for the control of the production of plutonium in the civil nuclear power reactor. The potential industrial application of the measurement of the thermal power of the nuclear plants by the neutrinos is also approached. earth neutrinos were for the first time highlighted in 2002 by the KamLAND experiment. Several international efforts are currently underway to use earth neutrinos to reveal the interior of the Earth. This meeting is an opportunity to adapt the efforts of detection to the real needs of geophysicists and geochemists (sources of radiogenic heat, potassium in the court, feathers.) Finally more futuristic topics such as the detection of nuclear explosions, of low powers, are also discussed. This document gathers only the slides of the presentations.

  2. Terrestrial and Reactor Antineutrinos in Borexino

    Science.gov (United States)

    Chen, M. C.; Calaprice, F. P.; Rothschild, C. G.

    1998-10-01

    The Earth is an abundant source of antineutrinos coming from the decay of radioactive elements in the mantle and crust. Detecting these antineutrinos is a challenge due to their small cross section and low energies. The Borexino solar neutrino experiment will also be an excellent detector for barν_e. With 300 tons of ultra-low-background liquid scintillator, surrounded by an efficient muon veto, the inverse-β-decay reaction: barνe + p arrow e^+ + n (Q = 1.8 MeV), can be exploited to detect terrestrial antineutrinos from the uranium and thorium decay chains, with little background. A direct measurement of the total uranium and thorium abundance would establish important geophysical constraints on the heat generation and thermal history of the Earth. Starting with the most recent uranium and thorium distribution and abundance data, and employing a global map of crustal type and thickness, we calculated the antineutrino fluxes for several sites. We estimate a terrestrial antineutrino event rate in Borexino of 10 events per year. This small signal can be distinguished over the neutrino background from the world's nuclear power reactors by measuring the positron energy spectrum from the barνe events. The possibility to perform a long-baseline oscillation experiment, reaching Δ m^2 ≈ 10-6 eV^2, using the nuclear reactors in Europe will also be discussed.

  3. Uncertainties in the Anti-neutrino Production at Nuclear Reactors

    OpenAIRE

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

    2008-01-01

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

  4. Applied Anti-neutrino Physics 2013

    CERN Document Server

    2013-01-01

    This year, the 9th annual Applied Antineutrino Physics Workshop will be hosted by Sejong University, at the COEX conference center in Seoul South Korea. The workshop will be held on November 1(Friday) - 2(Saturday), 2013. Conveniently for many travelers, it takes place directly after and at the same venue as the 2013 IEEE Nuclear Science Symposium (http://www.nss-mic.org/2013/NSSMain.asp) Applied Antineutrino Physics describes an ensemble of experimental and theoretical efforts which aim to use the antineutrino signal from nuclear reactors, and from the Earth itself, in order to address practical problems in nonproliferation and geology respectively. Since the 2004 inception of these workshops, groups worldwide have made considerable advances in defining and expanding the field, garnering interest from the International Atomic Energy Agency (IAEA), which administers the worlds most important nonproliferation regime, and from the geology/geophysics community. This meeting will focus on the current activi...

  5. Reactor Antineutrino Anomaly with known \\theta_{13}

    CERN Document Server

    Zhang, C; Vogel, P

    2013-01-01

    We revisit the reactor antineutrino anomaly using the recent reactor flux independent determination of sizable theta?13 by considering the full set of the absolute reactor electron antineutrino flux measurements. When normalized to the predicted flux of Mueller et al. [1], the new world average, after including results from Palo Verde, Chooz, and Double Chooz, is 0.959 +- 0.009 (experiment uncertainty) +- 0.027 (flux systematics). Including the data with kilometer baseline, the new world average is only about 1.4 sigma lower than the unity, weakening the significance of the reactor antineutrino anomaly. The upcoming results from Daya Bay, RENO, and the Double Chooz will provide further information about this issue.

  6. Antineutrino induced antikaon production off the nucleon

    CERN Document Server

    Alam, M Rafi; Athar, M Sajjad; Vacas, M J Vicente

    2011-01-01

    The charged current antikaon production off nucleons induced by antineutrinos is studied at low and intermediate energies. We extend here our previous calculation on kaon production induced by neutrinos. We have developed a microscopic model that starts from the SU(3) chiral Lagrangians and includes background terms and the resonant mechanisms associated to the lowest lying resonance in the channel, namely, the Sigma*(1385). Our results could be of interest for the background estimation of various neutrino oscillation experiments like MiniBooNE and SuperK. They can also be helpful for the planned antineutrino experiments like MINERvA, NOvA and T2K phase II and for beta-beam experiments with antineutrino energies around 1 GeV.

  7. Low-energy Antineutrinos from the Sun

    CERN Document Server

    Pastor, S; Valle, José W F; Pastor, Sergio; Semikoz, Viktor B.; Valle, Jose W.F.

    1998-01-01

    We consider the sensitivity of future neutrino experiments in the low energy region, such as BOREXINO or HELLAZ, to a solar electron antineutrino signal. We show that, if neutrino conversions within the Sun result in partial polarization of initial solar neutrino fluxes, then a new opportunity arises to observe the electron antineutrinos and thus to probe the Majorana nature of the neutrinos. This is achieved by comparing the slopes of the energy dependence of the differential neutrino electron scattering cross section for different neutrino conversion scenarios. We also show how the \

  8. Reactor antineutrino fluxes - status and challenges

    CERN Document Server

    Huber, Patrick

    2016-01-01

    In this contribution we describe the current understanding of reactor antineutrino fluxes and point out some recent developments. This is not intended to be a complete review of this vast topic but merely a selection of observations and remarks, which despite their incompleteness, will highlight the status and the challenges of this field.

  9. High flux lithium antineutrino source with variable hard spectrum

    CERN Document Server

    Lyashuk, V I

    2016-01-01

    The high flux antineutrino source with hard antineutrino spectrum based on neutron activation of 7Li and subsequent fast beta-decay (T 1/2 = 0.84 s) of the 8Li isotope with emission of antineutrino with energy up to 13 MeV - is discussed. Creation of the intensive isotope neutrino source of hard spectrum will allow to increase the detection statistics of neutrino interaction and it is especially urgent for oscillation experiments. The scheme of the proposed neutrino source is based on the continuous transport of the created 8Li to the neutrino detector, which moved away from the place of neutron activation. Analytical expressions for lithium antineutrino flux is obtained. The discussed source will ensure to increase the cross section for reactions with deuteron from several times to tens compare to the reactor antineutrino spectrum. An another unique feature of the installation is the possibility to vary smoothly the hardness of the antineutrino spectrum.

  10. Precisely determined the spent nuclear fuel antineutrino flux and spectrum for Daya Bay antineutrino experiment

    CERN Document Server

    Ma, X B; Chen, Y X; Zhong, W L; An, F P

    2015-01-01

    Spent nuclear fuel (SNF) antineutrino flux is an important source of uncertainties for a reactor neutrino flux prediction. However, if one want to determine the contribution of spent fuel, many data are needed, such as the amount of spent fuel in the pool, the time after discharged from the reactor core, the burnup of each assembly, and the antineutrino spectrum of the isotopes in the spend fuel. A method to calculate the contribution of SNF is proposed in this study. In this method, reactor simulation code verified by experiment have been used to simulate the fuel depletion by taking into account more than 2000 isotopes and fission products, the quantity of SNF in each six spend fuel pool, and the antineutrino spectrum of SNF varying with time after SNF discharged from core. Results show that the contribution of SNF to the total antineutrino flux is about 0.26%~0.34%, and the shutdown impact is about 20%. The SNF spectrum would distort the softer part of antineutrino spectra, and the maximum contribution fro...

  11. Nuclear Reactor Safeguards and Monitoring with Antineutrino Detectors

    OpenAIRE

    Bernstein, Adam; Wang, Yifang; Gratta, Giorgio; West, Todd

    2001-01-01

    Cubic-meter-sized antineutrino detectors can be used to non-intrusively, robustly and automatically monitor and safeguard a wide variety of nuclear reactor types, including power reactors, research reactors, and plutonium production reactors. Since the antineutrino spectra and relative yields of fissioning isotopes depend on the isotopic composition of the core, changes in composition can be observed without ever directly accessing the core itself. Information from a modest-sized antineutrino...

  12. The antineutrino energy structure in reactor experiments

    CERN Document Server

    Novella, P

    2015-01-01

    The recent observation of an energy structure in the reactor antineutrino spectrum is reviewed. The reactor experiments Daya Bay, Double Chooz and RENO have reported a consistent excess of antineutrinos deviating from the flux predictions, with a local significance of about 4$\\sigma$ between 4 and 6 MeV of the positron energy spectrum. The possible causes of the structure are analyzed in this work, along with the different experimental approaches developed to identify its origin. Considering the available data and results from the three experiments, the most likely explanation concerns the reactor flux predictions and the associated uncertainties. Therefore, the different current models are described and compared. The possible sources of incompleteness or inaccuracy of such models are discussed, as well as the experimental data required to improve their precision.

  13. Hanohano:A Deep Ocean Antineutrino Observatory

    CERN Document Server

    Batygov, M; Learned, J G; Matsuno, S; Pakvasa, S; Varner, G

    2008-01-01

    This paper presents the science potential of a deep ocean antineutrino observatory being developed at Hawaii and elsewhere. The observatory design allows for relocation from one site to another. Positioning the observaory some 60 km distant from a nuclear reactor complex enables preecision measurement of neutrino mixing parameters, leading to a determination of neutrino mass hierarchy and theta_13. At a mid-Pacific location, the observatory measures the flux of uranium and thorium decay series antineutrinos from earth's mantle and performs a sensitive search for a hypothetical natural fission reactor in earth's core. A subequent deployment at another mid-ocean location would test lateral homogeneity of uranium and thorium in earth's mantle. These measurements have significance for earth energy studies.

  14. JUNO: A Next Generation Reactor Antineutrino Experiment

    OpenAIRE

    Zhan, Liang

    2015-01-01

    The mass hierarchy and the CP phase are the main focus of the next generation neutrino oscillation experiments. Jiangmen Underground Neutrino Observatory (JUNO), as a medium baseline reactor antineutrino experiment, can determine the neutrino mass hierarchy independent of the CP phase. The physics potential on the mass hierarchy, and other measurements are reviewed. The preliminary design options for a 20~kton detector with an energy resolution of $3\\%/\\sqrt{E_{vis}}$ are illustrated. The mai...

  15. Nuclear reactor fissile isotopes antineutrino spectra

    OpenAIRE

    Sinev, V.

    2012-01-01

    Positron spectrum from inverse beta decay reaction on proton was measured in 1988-1990 as a result of neutrino exploration experiment. The measured spectrum has the largest statistics and lowest energy threshold between other neutrino experiments made that time at nuclear reactors. On base of the positron spectrum the standard antineutrino spectrum for typical reactor fuel composition was restored. In presented analysis the partial spectra forming this standard spectrum were extracted using s...

  16. Hanohano:A Deep Ocean Antineutrino Observatory

    OpenAIRE

    Batygov, M.; Dye, S. T.; Learned, J. G.; Matsuno, S; Pakvasa, S.; Varner, G.

    2008-01-01

    This paper presents the science potential of a deep ocean antineutrino observatory being developed at Hawaii and elsewhere. The observatory design allows for relocation from one site to another. Positioning the observaory some 60 km distant from a nuclear reactor complex enables preecision measurement of neutrino mixing parameters, leading to a determination of neutrino mass hierarchy and theta_13. At a mid-Pacific location, the observatory measures the flux of uranium and thorium decay serie...

  17. KamLAND, solar antineutrinos and the solar magnetic field

    CERN Document Server

    Chauhan, B C; Torrente-Lujan, E; Chauhan, Bhag C.; Pulido, Joao

    2003-01-01

    In this work the possibility of detecting solar electron antineutrinos produced by a solar core magnetic field from the KamLAND recent observations is investigated. We find a scaling of the antineutrino probability with respect to the magnetic field profile in the sense that the same probability function can be reproduced by any profile with a suitable peak field value. In this way the solar electron antineutrino spectrum can be unambiguosly predicted. We use this scaling and the negative results indicated by the KamLAND experiment to obtain upper bounds on the solar electron antineutrino flux. We get $\\phi_{\\bar\

  18. An improved measurement of muon antineutrino disappearance in MINOS

    OpenAIRE

    Adamson, P.; Ayres, D. S.; Backhouse, C.; Barr, G.; Bishai, M.; Blake, A.; Bock, G.J.; Boehnlein, D. J.; Bogert, D.; Cao, S. V.; Childress, S.; Coelho, J. A. B.; Corwin, L.; Cronin-Hennessy, D.; Danko, I. Z.

    2012-01-01

    We report an improved measurement of muon anti-neutrino disappearance over a distance of 735km using the MINOS detectors and the Fermilab Main Injector neutrino beam in a muon anti-neutrino enhanced configuration. From a total exposure of 2.95e20 protons on target, of which 42% have not been previously analyzed, we make the most precise measurement of the anti-neutrino "atmospheric" delta-m squared = 2.62 +0.31/-0.28 (stat.) +/- 0.09 (syst.) and constrain the anti-neutrino atmospheric mixing ...

  19. Theory of Antineutrino Monitoring of Burning MOX Plutonium Fuels

    CERN Document Server

    Hayes, A C; Nieto, Michael Martin; WIlson, W B

    2011-01-01

    This letter presents the physics and feasibility of reactor antineutrino monitoring to verify the burnup of plutonium loaded in the reactor as a Mixed Oxide (MOX) fuel. It examines the magnitude and temporal variation in the antineutrino signals expected for different MOX fuels, for the purposes of nuclear accountability and safeguards. The antineutrino signals from reactor-grade and weapons-grade MOX are shown to be distinct from those from burning low enriched uranium. Thus, antineutrino monitoring could be used to verify the destruction of plutonium in reactors, though verifying the grade of the plutonium being burned is found to be more challenging.

  20. JUNO: A Next Generation Reactor Antineutrino Experiment

    CERN Document Server

    Zhan, Liang

    2015-01-01

    The mass hierarchy and the CP phase are the main focus of the next generation neutrino oscillation experiments. Jiangmen Underground Neutrino Observatory (JUNO), as a medium baseline reactor antineutrino experiment, can determine the neutrino mass hierarchy independent of the CP phase. The physics potential on the mass hierarchy, and other measurements are reviewed. The preliminary design options for a 20~kton detector with an energy resolution of $3\\%/\\sqrt{E_{vis}}$ are illustrated. The main technical challenges on the PMT and scintillator are discussed and the corresponding R\\&D efforts are presented.

  1. Antineutrino reactor safeguards - a case study

    CERN Document Server

    Christensen, Eric; Jaffke, Patrick

    2013-01-01

    Antineutrinos have been proposed as a means of reactor safeguards for more than 30 years and there has been impressive experimental progress in neutrino detection. In this paper we conduct, for the first time, a case study of the application of antineutrino safeguards to a real-world scenario - the North Korean nuclear crisis in 1994. We derive detection limits to a partial or full core discharge in 1989 based on actual IAEA safeguards access and find that two independent methods would have yielded positive evidence for a second core with very high confidence. To generalize our results, we provide detailed estimates for the sensitivity to the plutonium content of various types of reactors, including most types of plutonium production reactors, based on detailed reactor simulations. A key finding of this study is that a wide class of reactors with a thermal power of less than 0.1-1 GWth can be safeguarded achieving IAEA goals for quantitative sensitivity and timeliness with detectors right outside the reactor ...

  2. Detection of Breeding Blankets Using Antineutrinos

    Science.gov (United States)

    Cogswell, Bernadette; Huber, Patrick

    2016-03-01

    The Plutonium Management and Disposition Agreement between the United States and Russia makes arrangements for the disposal of 34 metric tons of excess weapon-grade plutonium. Under this agreement Russia plans to dispose of its excess stocks by processing the plutonium into fuel for fast breeder reactors. To meet the disposition requirements this fuel would be burned while the fast reactors are run as burners, i.e., without a natural uranium blanket that can be used to breed plutonium surrounding the core. This talk discusses the potential application of antineutrino monitoring to the verification of the presence or absence of a breeding blanket. It is found that a 36 kg antineutrino detector, exploiting coherent elastic neutrino-nucleus scattering and made of silicon, could determine the presence of a breeding blanket at a liquid sodium cooled fast reactor at the 95% confidence level within 90 days. Such a detector would be a novel non-intrusive verification tool and could present a first application of coherent elastic neutrino-nucleus scattering to a real-world challenge.

  3. Long Distance Reactor Antineutrino Flux Monitoring

    Science.gov (United States)

    Dazeley, Steven; Bergevin, Marc; Bernstein, Adam

    2015-10-01

    The feasibility of antineutrino detection as an unambiguous and unshieldable way to detect the presence of distant nuclear reactors has been studied. While KamLAND provided a proof of concept for long distance antineutrino detection, the feasibility of detecting single reactors at distances greater than 100 km has not yet been established. Even larger detectors than KamLAND would be required for such a project. Considerations such as light attenuation, environmental impact and cost, which favor water as a detection medium, become more important as detectors get larger. We have studied both the sensitivity of water based detection media as a monitoring tool, and the scientific impact such detectors might provide. A next generation water based detector may be able to contribute to important questions in neutrino physics, such as supernova neutrinos, sterile neutrino oscillations, and non standard electroweak interactions (using a nearby compact accelerator source), while also providing a highly sensitive, and inherently unshieldable reactor monitoring tool to the non proliferation community. In this talk I will present the predicted performance of an experimental non proliferation and high-energy physics program. Lawrence Livermore National Laboratory is operated by Lawrence Livermore National Security, LLC, for the U.S. Department of Energy, National Nuclear Security Administration under Contract DE-AC52-07NA27344. Release number LLNL-ABS-674192.

  4. Testing Geological Models with Terrestrial Antineutrino Flux Measurements

    CERN Document Server

    Dye, Steve

    2009-01-01

    Uranium and thorium are the main heat producing elements in the earth. Their quantities and distributions, which specify the flux of detectable antineutrinos generated by the beta decay of their daughter isotopes, remain unmeasured. Geological models of the continental crust and the mantle predict different quantities and distributions of uranium and thorium. Many of these differences are resolvable with precision measurements of the terrestrial antineutrino flux. This precision depends on both statistical and systematic uncertainties. An unavoidable background of antineutrinos from nuclear reactors typically dominates the systematic uncertainty. This report explores in detail the capability of various operating and proposed geo-neutrino detectors for testing geological models.

  5. Hypersharp Resonant Capture of Anti-Neutrinos

    CERN Document Server

    Raghavan, R S

    2008-01-01

    Recent ideas suggest that the 18.6 keV antineutrino (nuebar) line from 2-body decay of 3H in crystals is emitted with natural width, motionally narrowed by lattice vibrations as in recoilless emission. It can be resonantly captured in 3He with geometrical cross section sigma ~10 ^ -17 cm2. A key technique solves a basic obstacle for achieving resonance--the chemical difference of H and He in metals. The low nue energy, the high sigma and the hypersharp sensitivity DELTA E/E ~10^--29 make an extraordinary tool for bench scale tests of nue theta13 oscillations and predicted Planck length limits on nuclear level widths in models of quantum gravity.

  6. Geoneutrinos and reactor antineutrinos at SNO+

    CERN Document Server

    Baldoncini, M; Wipperfurth, S A; Fiorentini, G; Mantovani, F; McDonough, W F; Ricci, B

    2016-01-01

    In the heart of the Creighton Mine near Sudbury (Canada), the SNO+ detector is foreseen to observe almost in equal proportion electron antineutrinos produced by U and Th in the Earth and by nuclear reactors. SNO+ will be the first long baseline experiment to measure a reactor signal dominated by CANDU cores ($\\sim$55\\% of the total reactor signal), which generally burn natural uranium. Approximately 18\\% of the total geoneutrino signal is generated by the U and Th present in the rocks of the Huronian Supergroup-Sudbury Basin: the 60\\% uncertainty on the signal produced by this lithologic unit plays a crucial role on the discrimination power on the mantle signal as well as on the geoneutrino spectral shape reconstruction, which can in principle provide a direct measurement of the Th/U ratio in the Earth.

  7. Estimating terrestrial uranium and thorium by antineutrino flux measurements

    Science.gov (United States)

    Dye, Stephen T.; Guillian, Eugene H.

    2008-01-01

    Uranium and thorium within the Earth produce a major portion of terrestrial heat along with a measurable flux of electron antineutrinos. These elements are key components in geophysical and geochemical models. Their quantity and distribution drive the dynamics, define the thermal history, and are a consequence of the differentiation of the Earth. Knowledge of uranium and thorium concentrations in geological reservoirs relies largely on geochemical model calculations. This article describes the methods and criteria to experimentally determine average concentrations of uranium and thorium in the continental crust and in the mantle by using site-specific measurements of the terrestrial antineutrino flux. Optimal, model-independent determinations involve significant exposures of antineutrino detectors remote from nuclear reactors at both a midcontinental and a midoceanic site. This would require major, new antineutrino detection projects. The results of such projects could yield a greatly improved understanding of the deep interior of the Earth. PMID:18172211

  8. Estimating terrestrial uranium and thorium by antineutrino flux measurements

    CERN Document Server

    Dye, Stephen T

    2008-01-01

    Uranium and thorium within the Earth produce a major portion of terrestrial heat along with a measurable flux of electron antineutrinos. These elements are key components in geophysical and geochemical models. Their quantity and distribution drive the dynamics, define the thermal history, and are a consequence of the differentiation of the Earth. Knowledge of uranium and thorium concentrations in geological reservoirs relies largely on geochemical model calculations. This research report describes the methods and criteria to experimentally determine average concentrations of uranium and thorium in the continental crust and in the mantle using site-specific measurements of the terrestrial antineutrino flux. Optimal, model-independent determinations involve significant exposures of antineutrino detectors remote from nuclear reactors at both a mid-continental and a mid-oceanic site. This would require major, new antineutrino detection projects. The results of such projects could yield a greatly improved understa...

  9. Observation of electron-antineutrino disappearance at Daya Bay

    CERN Document Server

    An, F P; Balantekin, A B; Band, H R; Beavis, D; Beriguete, W; Bishai, M; Blyth, S; Brown, R L; Cao, G F; Cao, J; Carr, R; Chan, W T; Chang, J F; Chang, Y; Chasman, C; Chen, H S; Chen, H Y; Chen, S J; Chen, S M; Chen, X C; Chen, X H; Chen, X S; Chen, Y; Chen, Y X; Cherwinka, J J; Chu, M C; Cummings, J P; Deng, Z Y; Ding, Y Y; Diwan, M V; Dong, L; Draeger, E; Du, X F; Dwyer, D A; Edwards, W R; Ely, S R; Fang, S D; Fu, J Y; Fu, Z W; Ge, L Q; Ghazikhanian, V; Gill, R L; Goett, J; Gonchar, M; Gong, G H; Gong, H; Gornushkin, Y A; Greenler, L S; Gu, W Q; Guan, M Y; Guo, X H; Hackenburg, R W; Hahn, R L; Hans, S; He, M; He, Q; He, W S; Heeger, K M; Heng, Y K; Hinrichs, P; Ho, T H; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, T; Hu, T; Huang, H X; Huang, H Z; Huang, P W; Huang, X; Huang, X T; Huber, P; Isvan, Z; Jaffe, D E; Jetter, S; Ji, X L; Ji, X P; Jiang, H J; Jiang, W Q; Jiao, J B; Johnson, R A; Kang, L; Kettell, S H; Kramer, M; Kwan, K K; Kwok, M W; Kwok, T; Lai, C Y; Lai, W C; Lai, W H; Lau, K; Lebanowski, L; Lee, J; Lee, M K P; Leitner, R; Leung, J K C; Leung, K Y; Lewis, C A; Li, B; Li, F; Li, G S; Li, J; Li, Q J; Li, S F; Li, W D; Li, X B; Li, X N; Li, X Q; Li, Y; Li, Z B; Liang, H; Liang, J; Lin, C J; Lin, G L; Lin, S K; Lin, S X; Lin, Y C; Ling, J J; Link, J M; Littenberg, L; Littlejohn, B R; Liu, B J; Liu, C; Liu, D W; Liu, H; Liu, J C; Liu, J L; Liu, S; Liu, X; Liu, Y B; Lu, C; Lu, H Q; Luk, A; Luk, K B; Luo, T; Luo, X L; Ma, L H; Ma, Q M; Ma, X B; Ma, X Y; Ma, Y Q; Mayes, B; McDonald, K T; McFarlane, M C; McKeown, R D; Meng, Y; Mohapatra, D; Morgan, J E; Nakajima, Y; Napolitano, J; Naumov, D; Nemchenok, I; Newsom, C; Ngai, H Y; Ngai, W K; Nie, Y B; Ning, Z; Ochoa-Ricoux, J P; Olshevski, A; Pagac, A; Patton, S; Pearson, C; Pec, V; Peng, J C; Piilonen, L E; Pinsky, L; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Raper, N; Rosero, R; Roskovec, B; Ruan, X C; Seilhan, B; Shao, B B; Shih, K; Steiner, H; Stoler, P; Sun, G X; Sun, J L; Tam, Y H; Tanaka, H K; Tang, X; Themann, H; Torun, Y; Trentalange, S; Tsai, O; Tsang, K V; Tsang, R H M; Tull, C; Viren, B; Virostek, S; Vorobel, V; Wang, C H; Wang, L S; Wang, L Y; Wang, L Z; Wang, M; Wang, N Y; Wang, R G; Wang, T; Wang, W; Wang, X; Wang, X; Wang, Y F; Wang, Z; Wang, Z; Wang, Z M; Webber, D M; Wei, Y D; Wen, L J; Wenman, D L; Whisnant, K; White, C G; Whitehead, L; Whitten, C A; Wilhelmi, J; Wise, T; Wong, H C; Wong, H L H; Wong, J; Worcester, E T; Wu, F F; Wu, Q; Xia, D M; Xiang, S T; Xiao, Q; Xing, Z Z; Xu, G; Xu, J; Xu, J; Xu, J L; Xu, W; Xu, Y; Xue, T; Yang, C G; Yang, L; Ye, M; Yeh, M; Yeh, Y S; Yip, K; Young, B L; Yu, Z Y; Zhan, L; Zhang, C; Zhang, F H; Zhang, J W; Zhang, Q M; Zhang, K; Zhang, Q X; Zhang, S H; Zhang, Y C; Zhang, Y H; Zhang, Y X; Zhang, Z J; Zhang, Z P; Zhang, Z Y; Zhao, J; Zhao, Q W; Zhao, Y B; Zheng, L; Zhong, W L; Zhou, L; Zhou, Z Y; Zhuang, H L; Zou, J H

    2012-01-01

    The Daya Bay Reactor Neutrino Experiment has measured a non-zero value for the neutrino mixing angle $\\theta_{13}$ with a significance of 5.2 standard deviations. Antineutrinos from six 2.9 GW$_{\\rm th}$ reactors were detected in six antineutrino detectors deployed in two near (flux-weighted baseline 470 m and 576 m) and one far (1648 m) underground experimental halls. With 55 days of data, 10416 (80376) electron antineutrino candidates were detected at the far hall (near halls). The ratio of the observed to expected number of antineutrinos at the far hall is $R=0.940\\pm 0.011({\\rm stat}) \\pm 0.004({\\rm syst})$. A rate-only analysis finds $\\sin^22\\theta_{13}=0.092\\pm 0.016({\\rm stat})\\pm0.005({\\rm syst})$ in a three-neutrino framework.

  10. First Antineutrino Oscillation Results from T2K

    CERN Document Server

    Duffy, Kirsty

    2016-01-01

    As limits improve on the neutrino mixing angles and mass-squared differences, the focus of T2K has shifted towards studying antineutrino oscillation. This will give an insight into CP violation (if P($\\bar{\

  11. Discriminating among Earth composition models using geo-antineutrinos

    OpenAIRE

    H. Nunokawa(Departamento de Física, Pontifícia Universidade Católica do Rio de Janeiro, C.P. 38071, 22452-970, Rio de Janeiro, Brazil); Teves, W. J. C.; Funchal, R. Zukanovich

    2003-01-01

    It has been estimated that the entire Earth generates heat corresponding to about 40 TW (equivalent to 10,000 nuclear power plants) which is considered to originate mainly from the radioactive decay of elements like U, Th and K, deposited in the crust and mantle of the Earth. Radioactivity of these elements produce not only heat but also antineutrinos (called geo-antineutrinos) which can be observed by terrestrial detectors. We investigate the possibility of discriminating among Earth composi...

  12. Testing Geological Models with Terrestrial Antineutrino Flux Measurements

    OpenAIRE

    Dye, Steve

    2009-01-01

    Uranium and thorium are the main heat producing elements in the earth. Their quantities and distributions, which specify the flux of detectable antineutrinos generated by the beta decay of their daughter isotopes, remain unmeasured. Geological models of the continental crust and the mantle predict different quantities and distributions of uranium and thorium. Many of these differences are resolvable with precision measurements of the terrestrial antineutrino flux. This precision depends on bo...

  13. Antineutrino analysis for continuous monitoring of nuclear reactors: Sensitivity study

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, Christopher; Erickson, Anna [Georgia Institute of Technology, Nuclear and Radiological Engineering, G. W. Woodruff School of Mechanical Engineering, 770 State St. NW, Atlanta, Georgia 30332 (United States)

    2015-10-28

    This paper explores the various contributors to uncertainty on predictions of the antineutrino source term which is used for reactor antineutrino experiments and is proposed as a safeguard mechanism for future reactor installations. The errors introduced during simulation of the reactor burnup cycle from variation in nuclear reaction cross sections, operating power, and other factors are combined with those from experimental and predicted antineutrino yields, resulting from fissions, evaluated, and compared. The most significant contributor to uncertainty on the reactor antineutrino source term when the reactor was modeled in 3D fidelity with assembly-level heterogeneity was found to be the uncertainty on the antineutrino yields. Using the reactor simulation uncertainty data, the dedicated observation of a rigorously modeled small, fast reactor by a few-ton near-field detector was estimated to offer reduction of uncertainty on antineutrino yields in the 3.0–6.5 MeV range to a few percent for the primary power-producing fuel isotopes, even with zero prior knowledge of the yields.

  14. Monitoring Nuclear Reactors with Antineutrino Detectors: The ANGRA Project

    International Nuclear Information System (INIS)

    Nuclear reactors are intense source of antineutrinos and the thermal power released in the fission process is directly related to the emitted antineutrino flux. As antineutrinos interact very weekly with matter and escape the reactor containment without any significant change in their number, measuring the antineutrino flux can give quasi real time information on the reactor status (on/off) and thermal power. Furthermore as the amount of fissile elements change during the burn up of the nuclear fuel and each fissile isotope has a characteristic antineutrino energy spectrum, measuring the antineutrino energy spectrum escaping the reactor can give also information on the composition of the nuclear fuel. These unique features make antineutrino detectors good candidates to become in the near future a new safeguards tool for monitoring nuclear reactors through counting rates and spectral antineutrino measurements. We will present the status of the ANGRA Neutrinos project, aimed at developing an antineutrino detector for monitoring nuclear reactor activity. The Angra experiment will be deployed at the Brazilian nuclear power plant Angra II. A water Cherenkov detector of one ton target will be placed in a commercial container just outside the reactor containment, about 30 m of the reactor core. The 4 GW thermal power of the Angra II reactor will provide a few thousand antineutrino inverse beta decay interactions per day. The main challenge of the experiment will be to overcome the very high cosmic ray induced background at sea level, consisting mainly of muons, neutrons, gammas and electrons. We have estimated a muon flux of the order of 350 Hz and a neutron flux of about 4 Hz (left after the polyethylene shielding) in the target region. To overcome the background the detector will consist of three subsystems: 1) a muon veto 99% efficient placed in the outer most detector layer; 2) a neutron shield 30cm thick consisting of polyethylene sheets; 3) a central detector

  15. Experimental determination of the antineutrino spectrum of the fission products of 238U

    International Nuclear Information System (INIS)

    Fission of 238U contributes about 10 % to the antineutrino emission of a pressurized water reactor. In the present thesis, the beta spectrum of the fission products of 238U was determined in an experiment at the neutron source FRM II. This beta spectrum was subsequently converted into an antineutrino spectrum. This first measurement of the antineutrino spectrum supports all current and future reactor antineutrino experiments.

  16. Experimental determination of the antineutrino spectrum of the fission products of {sup 238}U

    Energy Technology Data Exchange (ETDEWEB)

    Haag, Nils-Holger

    2013-10-09

    Fission of {sup 238}U contributes about 10 % to the antineutrino emission of a pressurized water reactor. In the present thesis, the beta spectrum of the fission products of {sup 238}U was determined in an experiment at the neutron source FRM II. This beta spectrum was subsequently converted into an antineutrino spectrum. This first measurement of the antineutrino spectrum supports all current and future reactor antineutrino experiments.

  17. Discriminating among Earth composition models using geo-antineutrinos

    CERN Document Server

    Nunokawa, H; Zukanovich-Funchal, R

    2003-01-01

    It has been estimated that the entire Earth generates heat corresponding to about 40 TW (equivalent to 10,000 nuclear power plants) which is considered to originate mainly from the radioactive decay of elements like U, Th and K, deposited in the crust and mantle of the Earth. Radioactivity of these elements produce not only heat but also antineutrinos (called geo-antineutrinos) which can be observed by terrestrial detectors. We investigate the possibility of discriminating among Earth composition models predicting different total radiogenic heat generation, by observing such geo-antineutrinos at Kamioka and Gran Sasso, assuming KamLAND and Borexino (type) detectors, respectively, at these places. By simulating the future geo-antineutrino data as well as reactor antineutrino background contributions, we try to establish to which extent we can discriminate among Earth composition models for given exposures (in units of kt$\\cdot$ yr) at these two sites on our planet. We use also information on neutrino mixing pa...

  18. KamLAND, solar antineutrinos and their magnetic moment

    CERN Document Server

    Aliani, P; Picariello, M; Torrente-Lujan, E

    2003-01-01

    We investigate the possibility of detecting solar antineutrinos with the KamLAND experiment. These antineutrinos are predicted by spin-flavor oscillations at a significant rate even if this mechanism is not the leading solution to the SNP. The recent evidence from SNO shows that a) the neutrino oscillates, only around 34% of the initial solar neutrinos arrive at the Earth as electron neutrinos and b) the conversion is mainly into active neutrinos, however a non e, mu, tau component is allowed: the fraction of oscillation into non-mu-tau neutrinos is found to be cos^2(alpha) = 0.08^{+0.20}_{-0.40}. This residual flux could include sterile neutrinos and/or the antineutrinos of the active flavors. KamLAND is potentially sensitive to antineutrinos derived from solar ^8 B neutrinos. In case of negative results, we find that KamLAND could put strict limits on the flux of solar antineutrinos, Phi(^8 B) < 1.0 times 10^4 cm^{-2} s^{-1}, more than one order of magnitude smaller than existing limits, and on their app...

  19. Yale High Energy Physics Research: Precision Studies of Reactor Antineutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Heeger, Karsten M. [Yale Univ., New Haven, CT (United States)

    2014-09-13

    This report presents experimental research at the intensity frontier of particle physics with particular focus on the study of reactor antineutrinos and the precision measurement of neutrino oscillations. The experimental neutrino physics group of Professor Heeger and Senior Scientist Band at Yale University has had leading responsibilities in the construction and operation of the Daya Bay Reactor Antineutrino Experiment and made critical contributions to the discovery of non-zero$\\theta_{13}$. Heeger and Band led the Daya Bay detector management team and are now overseeing the operations of the antineutrino detectors. Postdoctoral researchers and students in this group have made leading contributions to the Daya Bay analysis including the prediction of the reactor antineutrino flux and spectrum, the analysis of the oscillation signal, and the precision determination of the target mass yielding unprecedented precision in the relative detector uncertainty. Heeger's group is now leading an R\\&D effort towards a short-baseline oscillation experiment, called PROSPECT, at a US research reactor and the development of antineutrino detectors with advanced background discrimination.

  20. Antineutrino monitoring for the Iranian heavy water reactor

    CERN Document Server

    Christensen, Eric; Jaffke, Patrick; Shea, Thomas

    2014-01-01

    In this note we discuss the potential application of antineutrino monitoring to the Iranian heavy water reactor at Arak, the IR-40, as a non-proliferation measure. We demonstrate that an above ground detector positioned right outside the IR-40 reactor building could meet and in some cases significantly exceed the verification goals identified by IAEA for plutonium production or diversion from declared inventories. In addition to monitoring the reactor during operation, observing antineutrino emissions from long-lived fission products could also allow monitoring the reactor when it is shutdown. Antineutrino monitoring could also be used to distinguish different levels of fuel enrichment. Most importantly, these capabilities would not require a complete reactor operational history and could provide a means to re-establish continuity of knowledge in safeguards conclusions should this become necessary.

  1. A reference worldwide model for antineutrinos from reactors

    CERN Document Server

    Baldoncini, Marica; Fiorentini, Giovanni; Mantovani, Fabio; Ricci, Barbara; Strati, Virginia; Xhixha, Gerti

    2014-01-01

    Antineutrinos produced at nuclear reactors constitute a severe source of background for the detection of geoneutrinos, which bring to the Earth's surface information about natural radioactivity in the whole planet. In this framework we provide a reference worldwide model for antineutrinos from reactors, in view of reactors operational records yearly published by the International Atomic Energy Agency (IAEA). We evaluate the expected signal from commercial reactors for ongoing (KamLAND and Borexino), planned (SNO+) and proposed (Juno, RENO-50, LENA and Hanohano) experimental sites. Uncertainties related to reactor antineutrino production, propagation and detection processes are estimated using a Monte Carlo based approach, which provides an overall site dependent uncertainty on the signal in the geoneutrino energy window on the order of 3%. We also implement the off-equilibrium correction to the reference reactor spectra associated with the long-lived isotopes and we estimate a 2.4% increase of the unoscillate...

  2. Neutrino geophysics at Baksan I: possible detection of georeactor antineutrinos

    International Nuclear Information System (INIS)

    J.M. Herndon in 90s proposed a natural nuclear fission georeactor at the center of the Earth with a power output of 3 - 10 TW as an energy source to sustain the Earth magnetic field. R.S. Raghavan in 2002 pointed out that under certain condition antineutrinos generated in georeactor can be detected using massive scintillation detectors. It is considered that underground Baksan Neutrino Observatory (4880 m w.e.) as a possible site dor development in Geoneutrino physics. Here the intrinsic background level of less than 1 event/yr in a liquid scintillation ∼1000-t target detector can be achieved and the main source of background is the antineutrino flux from power reactors. It is find that this flux is ∼ 10 times lower than at KamLAND detector site and two times lower than at Gran Sasso laboratory and thus at Baksan the georeactor burning nuclear fuel by analysis of the antineutrino energy spectrum

  3. Antineutrino flux from the Laguna Verde Nuclear Power Plant

    CERN Document Server

    Chavez-Estrada, Marisol

    2015-01-01

    We present a a calculation of the antineutrino flux produced by the reactors at the Laguna Verde Nuclear Power Plant in M\\'exico, based on the antineutrino spectra produced in the decay chains of the fission fragments of the main isotopes in the reactor core, and their fission rates, that have been calculated using the DRAGON simulation code. We also present an estimate of the number of expected events in a detector made of plastic scintillator with a mass of 1 ton, at 100 m from the reactor cores.

  4. Is there a high-y anomaly in antineutrino interactions

    International Nuclear Information System (INIS)

    We have analyzed data taken in the CERN narrow-band neutrino and antineutrino beams with regard to the ''high-y anomaly'' observed by previous experiments at Fermilab. At neutrino energies between 30 and 200 GeV, the anti ν and ν charged-current cross-section ratios and muon-inelasticity distributions disagree with the earlier results. In particular, there is no evidence for energy-dependent effects in the antineutrino data which constitute an important aspect of the alleged anomaly

  5. Investigation of Large LGB Detectors for Antineutrino Detection

    CERN Document Server

    Nelson, P

    2011-01-01

    A detector material or configuration that can provide an unambiguous indication of neutron capture can substantially reduce random coincidence backgrounds in antineutrino detection and capture-gated neutron spectrometry applications. Here we investigate the performance of such a material, a composite of plastic scintillator and $^6$Li$_6^{nat}$Gd$(^{10}$BO$_{3})_{3}$:Ce (LGB) crystal shards of ~1 mm dimension and comprising 1% of the detector by mass. While it is found that the optical propagation properties of this material as currently fabricated are only marginally acceptable for antineutrino detection, its neutron capture identification ability is encouraging.

  6. Investigation of large LGB detectors for antineutrino detection

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, P. [Department of Physics, Naval Postgraduate School, Monterey, CA 93943 (United States); Bowden, N.S., E-mail: nbowden@llnl.gov [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States)

    2011-12-21

    A detector material or configuration that can provide an unambiguous indication of neutron capture can substantially reduce random coincidence backgrounds in antineutrino detection and capture-gated neutron spectrometry applications. Here we investigate the performance of such a material, a composite of plastic scintillator and {sup 6}Li{sub 6}{sup nat}Gd({sup 10}BO{sub 3}){sub 3}:Ce (LGB) crystal shards of Almost-Equal-To 1 mm dimension and comprising 1% of the detector by mass. While it is found that the optical propagation properties of this material as currently fabricated are only marginally acceptable for antineutrino detection, its neutron capture identification ability is encouraging.

  7. Measuring Antineutrino Oscillations with the MINOS Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Evans, Justin John [Univ. of Oxford (United Kingdom)

    2008-09-01

    MINOS is a long baseline neutrino oscillation experiment. A manmade beam of predominantly muon neutrinos is detected both 1 km and 735 km from the production point by two functionally identical detectors. A comparison of the energy spectra measured by the two detectors shows the energy-dependent disappearance of muon neutrinos characteristic of oscillations and allows a measurement of the parameters governing the oscillations. This thesis presents work leading to measurements of disappearance in the 6% $\\bar{v}$μ background in that beam. A calibration is developed to correct for time-dependent changes in the responses of both detectors, reducing the corresponding uncertainty on hadronic energy measurements from 1.8% to 0.4% in the near detector and from 0.8% to 0.4% in the far detector. A method of selecting charged current $\\bar{v}$μ events is developed, with purities (efficiencies) of 96.5% (74.4%) at the near detector, and 98.8% (70.9%) at the far detector in the region below 10 GeV reconstructed antineutrino energy. A method of using the measured near detector neutrino energy spectrum to predict that expected at the far detector is discussed, and developed for use in the $\\bar{v}$μ analysis. Sources of systematic uncertainty contributing to the oscillation measurements are discussed. In the far detector, 32 charged current $\\bar{v}$μ events are observed below a reconstructed energy of 30 GeV, compared to an expectation of 47.8 for Δ$\\bar{m}$atm2 = Δ$\\bar{m}$atm2, sin2(2$\\bar{θ}$23) = sin2(2θ23). This deficit, in such a low-statistics sample, makes the result difficult to interpret in the context of an oscillation parameter measurement. Possible sources for the discrepancy are discussed, concluding that considerably more data are required for a definitive solution. Running MINOS with a dedicated $\\bar

  8. Measuring Antineutrino Oscillations with the MINOS Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Evans, Justin John; /Oxford U.

    2008-09-01

    MINOS is a long baseline neutrino oscillation experiment. A manmade beam of predominantly muon neutrinos is detected both 1 km and 735 km from the production point by two functionally identical detectors. A comparison of the energy spectra measured by the two detectors shows the energy-dependent disappearance of muon neutrinos characteristic of oscillations and allows a measurement of the parameters governing the oscillations. This thesis presents work leading to measurements of disappearance in the 6% {bar {nu}}{sub {mu}} background in that beam. A calibration is developed to correct for time-dependent changes in the responses of both detectors, reducing the corresponding uncertainty on hadronic energy measurements from 1.8% to 0.4% in the near detector and from 0.8% to 0.4% in the far detector. A method of selecting charged current {bar {nu}}{sub {mu}} events is developed, with purities (efficiencies) of 96.5% (74.4%) at the near detector, and 98.8% (70.9%) at the far detector in the region below 10 GeV reconstructed antineutrino energy. A method of using the measured near detector neutrino energy spectrum to predict that expected at the far detector is discussed, and developed for use in the {bar {nu}}{sub {mu}} analysis. Sources of systematic uncertainty contributing to the oscillation measurements are discussed. In the far detector, 32 charged current {bar {nu}}{sub {mu}} events are observed below a reconstructed energy of 30 GeV, compared to an expectation of 47.8 for {Delta}{bar m}{sub atm}{sup 2} = {Delta}m{sub atm}{sup 2}, sin{sup 2}(2{bar {theta}}{sub 23}) = sin{sup 2}(2{theta}{sub 23}). This deficit, in such a low-statistics sample, makes the result difficult to interpret in the context of an oscillation parameter measurement. Possible sources for the discrepancy are discussed, concluding that considerably more data are required for a definitive solution. Running MINOS with a dedicated {bar {nu}}{sub {mu}} beam would be the ideal continuation of this

  9. Monitoring Akkuyu Nuclear Reactor Using Anti-Neutrino Flux Measurement

    CERN Document Server

    Ozturk, Sertac; Ozcan, V Erkcan; Unel, Gokhan

    2016-01-01

    We present a simulation based study for monitoring Akkuyu Nuclear Power Plant's activity using anti-neutrino flux originating from the reactor core. A water Cherenkov detector has been designed and optimization studies have been performed using Geant4 simulation toolkit. A first study for the design of a monitoring detector facility for Akkuyu Nuclear Power Plant has been discussed in this paper.

  10. Neutron capture and the antineutrino yield from nuclear reactors

    CERN Document Server

    Huber, Patrick

    2015-01-01

    We identify a new, flux-dependent correction to the antineutrino spectrum as produced in nuclear reactors. The abundance of certain nuclides, whose decay chains produce antineutrinos above the threshold for inverse beta decay, has a nonlinear dependence on the neutron flux, unlike the vast majority of antineutrino producing nuclides, whose decay rate is directly related to the fission rate. We have identified four of these so-called nonlinear nuclides and determined that they result in an antineutrino excess at low-energies below 3.2MeV, dependent on the reactor thermal neutron flux. We develop an analytic model for the size of the correction and compare it to the results of detailed reactor simulations for various real existing reactors, spanning 3 orders of magnitude in neutron flux. In a typical pressurized water reactor the resulting correction can reach 0.9% of the low energy flux which is comparable in size to other, known low-energy corrections from spent nuclear fuel and the non-equilibrium correction...

  11. Method for measuring the electron antineutrino rest mass

    Energy Technology Data Exchange (ETDEWEB)

    Lobashev, V.M.; Spivak, P.E.

    1985-10-15

    A method is proposed for measuring the tritium beta spectrum in order to determine the electron antineutrino rest mass. This method includes an electrostatic integral spectrometer with adiabatic collimation. The use of a source in the form of atomic polarized tritium in a strong magnetic field or of a gaseous molecular source is considered. (orig.).

  12. Observation of Reactor Electron Antineutrino Disappearance at RENO

    International Nuclear Information System (INIS)

    The Reactor Experiment for Neutrino Oscillation (RENO) has obtained a definitive measurement of the smallest neutrino mixing angle of θ13 by observing the disappearance of electron antineutrinos emitted from a nuclear reactor, excluding the no-oscillation hypothesis at 4.9 σ. From the deficit, the best fit value of sin22θ13 is obtained as 0.113±0.013(stat.)±0.019(syst.) based on a rate-only analysis. Antineutrinos from six 2.8 GWth reactors at the Yonggwang Nuclear Power Plant in Korea, are detected by two identical detectors at 294 m and 1383 m, respectively, from the reactor array center. In the 229 day data-taking period between 11 August 2011 and 26 March 2012, the far (near) detector observed 17102 (154088) electron antineutrino candidate events with a background fraction of 5.5% (2.7%). The ratio of observed to expected numbers of the reactor antineutrinos in the far detector is 0.920±0.009(stat.)±0.014(syst.)

  13. Electron Neutrino and Antineutrino Appearance in the MINOS Detector

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-04-01

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

  14. Improved Measurement of Electron Antineutrino Disappearance at Daya Bay

    CERN Document Server

    An, F P; Balantekin, A B; Band, H R; Beriguete, W; Bishai, M; Blyth, S; Brown, R L; Cao, G F; Cao, J; Carr, R; Chan, W T; Chang, J F; Chang, Y; Chasman, C; Chen, H S; Chen, H Y; Chen, S J; Chen, S M; Chen, X C; Chen, X H; Chen, X S; Chen, Y; Chen, Y X; Cherwinka, J J; Chu, M C; Cummings, J P; Deng, Z Y; Ding, Y Y; Diwan, M V; Dong, L; Draeger, E; Dwyer, D; Edwards, W R; Ely, S R; Fang, S D; Fu, J Y; Fu, Z W; Ge, L Q; Gill, R L; Gonchar, M; Gong, G H; Gong, H; Gornushkin, Y A; Greenler, L S; Gu, W Q; Guan, M Y; Guo, X H; Hackenburg, R W; Hahn, R L; Hans, S; He, M; He, Q; Heeger, K M; Heng, Y K; Hinrichs, P; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, T; Huang, H X; Huang, H Z; Huang, X T; Huber, P; Issakov, V; Isvan, Z; Jaffe, D E; Jetter, S; Ji, X L; Ji, X P; Jiang, H J; Jiang, W Q; Jiao, J B; Johnson, R A; Kang, L; Kettell, S H; Kramer, M; Kwan, K K; Kwok, M W; Kwok, T; Lai, C Y; Lai, W C; Lai, W H; Lau, K; Lebanowski, L; Lee, J; Leitner, R; Leung, J K C; Leung, K Y; Lewis, C A; Li, B; Li, F; Li, G S; Li, J; Li, Q J; Li, S F; Li, W D; Li, X B; Li, X N; Li, X Q; Li, Y; Li, Z B; Liang, H; Liang, J; Lin, C J; Lin, G L; Lin, S K; Lin, S X; Lin, Y C; Ling, J J; Link, J M; Littenberg, L; Littlejohn, B R; Liu, B J; Liu, D W; Liu, J C; Liu, J L; Liu, S; Liu, Y B; Lu, C; Lu, H Q; Luk, A; Luk, K B; Luo, T; Luo, X L; Ma, Q M; Ma, X B; Ma, X Y; Ma, Y Q; McDonald, K T; McFarlane, M C; McKeown, R D; Meng, Y; Mohapatra, D; Morgan, J E; Nakajima, Y; Napolitano, J; Naumov, D; Nemchenok, I; Ngai, H Y; Ngai, W K; Nie, Y B; Ning, Z; Ochoa-Ricoux, J P; Olshevski, A; Pagac, A; Patton, S; Pec, V; Peng, J C; Piilonen, L E; Pinsky, L; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Raper, N; Rosero, R; Roskovec, B; Ruan, X C; Shao, B B; Shih, K; Steiner, H; Stoler, P; Sun, G X; Sun, J L; Tam, Y H; Tanaka, H K; Tang, X; Tagg, N; Themann, H; Torun, Y; Trentalange, S; Tsai, O; Tsang, R H M; Tsang, K V; Tull, C; Tung, Y C; Viren, B; Virostek, S; Vorobel, V; Wang, C H; Wang, L S; Wang, L Y; Wang, L Z; Wang, M; Wang, N Y; Wang, R G; Wang, T; Wang, W; Wang, X; Wang, X; Wang, Y F; Wang, Z; Wang, Z; Wang, Z M; Webber, D M; Wei, Y D; Wen, L J; Wenman, D L; Whisnant, K; White, C G; Whitehead, L; Wilhelmi, J; Williamson, Y; Wise, T; Wong, H L H; Wong, J; Worcester, E T; Wu, F F; Wu, Q; Xia, D M; Xiang, S T; Xiao, Q; Xing, Z Z; Xu, J; Xu, J; Xu, J L; Xu, W; Xu, Y; Xue, T; Yang, C G; Yang, L; Ye, M; Yeh, M; Yeh, Y S; Young, B L; Yu, Z Y; Zhan, L; Zhang, C; Zhang, F H; Zhang, J W; Zhang, Q M; Zhang, Q X; Zhang, S H; Zhang, Y C; Zhang, Y H; Zhang, Y X; Zhang, Z J; Zhang, Z P; Zhang, Z Y; Zhao, J; Zhao, Q W; Zhao, Y B; Zheng, L; Zhong, W L; Zhou, L; Zhou, Z Y; Zhuang, H L; Zou, J H

    2012-01-01

    We report an improved measurement of the neutrino mixing angle $\\theta_{13}$ from the Daya Bay Reactor Neutrino Experiment. We exclude a zero value for $\\sin^22\\theta_{13}$ with a significance of 7.7 standard deviations. Electron antineutrinos from six reactors of 2.9 GW$_{\\rm th}$ were detected in six antineutrino detectors deployed in two near (flux-weighted baselines of 470 m and 576 m) and one far (1648 m) underground experimental halls. Using 139 days of data, 28909 (205308) electron antineutrino candidates were detected at the far hall (near halls). The ratio of the observed to the expected number of antineutrinos assuming no oscillations at the far hall is $0.944\\pm 0.007({\\rm stat.}) \\pm 0.003({\\rm syst.})$. An analysis of the relative rates in six detectors finds $\\sin^22\\theta_{13}=0.089\\pm 0.010({\\rm stat.})\\pm0.005({\\rm syst.})$ in a three-neutrino framework.

  15. Captures of Hot and Warm Sterile Antineutrino Dark Matter on EC-decaying Ho-163 Nuclei

    CERN Document Server

    Li, Y F

    2011-01-01

    Capturing low-energy electron antineutrinos on radioactive Ho-163 nuclei, which decay into Dy-163 via electron capture (EC), is a noteworthy opportunity to detect relic sterile antineutrinos. Such hypothetical particles are more or less implied by current experimental and cosmological data, and they might be a part of hot dark matter or a candidate for warm dark matter in the Universe. Using the isotope Ho-163 as a target and assuming reasonable active-sterile antineutrino mixing angles, we calculate the capture rate of relic electron antineutrinos against the corresponding EC-decay background in the presence of sterile antineutrinos at the sub-eV or keV mass scale. We show that the signature of hot or warm sterile antineutrino dark matter should in principle be observable, provided the target is big enough and the energy resolution is good enough.

  16. Which reactor antineutrino flux may be responsible for the anomaly?

    CERN Document Server

    Giunti, Carlo

    2016-01-01

    We investigate which among the reactor antineutrino fluxes from the decays of the fission products of $^{235}\\text{U}$, $^{238}\\text{U}$, $^{239}\\text{Pu}$, and $^{241}\\text{Pu}$ may be responsible for the reactor antineutrino anomaly. We find that it is the $^{235}\\text{U}$ flux, which contributes to the rates of all reactor neutrino experiments. From the fit of the data we obtain the precise determination $ \\sigma_{^{235}\\text{U}} = ( 6.34 \\pm 0.10 ) \\times 10^{-43} \\, \\text{cm}^2 / \\text{fission} $ of the $^{235}\\text{U}$ cross section per fission, which is more precise than the calculated value and differs from it by $2.0\\sigma$.

  17. Neutrino mass hierarchy determination at reactor antineutrino experiments

    CERN Document Server

    Yang, Guang

    2015-01-01

    After the neutrino mixing angle $\\theta_{13}$ has been precisely measured by the reactor antineutrino experiments, one of the most important open questions left in neutrino physics is the neutrino mass hierarchy. Jiangmen Underground Neutrino Observatory (JUNO) is designed to determine the neutrino mass hierarchy (MH) without exploring the matter effect. The JUNO site location is optimized to have the best sensitivity for the mass hierarchy determination. JUNO will employ a 20 kton liquid scintillator detector located in a laboratory 700 meters underground. The excellent energy resolution and PMT coverage will give us an unprecedented opportunity to reach a 3-4 $\\sigma$ precision. In this paper, the JUNO detector design and simulation work will be presented. Also, RENO-50, another medium distance reactor antineutrino experiment, will do a similar measurement. With the efforts of these experiments, it is very likely that the neutrino mass hierarchy will be determined in the next 10 years.

  18. Development of PROSPECT detectors for precision antineutrino studies

    CERN Document Server

    Norcini, Danielle

    2015-01-01

    PROSPECT, the Precision Reactor Oscillation and Spectrum Experiment, will use two segmented detectors positioned 7-20 m from the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory to measure the U-235 antineutrino spectrum and perform a search for short-baseline oscillations as a signature of eV-scale sterile neutrinos. PROSPECT has developed Li-6 loaded liquid scintillator detectors for efficient identification of reactor antineutrinos and has measured reactor and cosmogenic backgrounds in the HFIR reactor building. Multiple test detectors have been built, operated, and characterized at HFIR and elsewhere to understand the optical performance of the scintillator and pulse-shape discrimination capabilities for enhanced background rejection. The results from this R&D effort are discussed, in the context of the design and physics potential of PROSPECT.

  19. Development of an advanced antineutrino detector for reactor monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Classen, T., E-mail: classen2@llnl.gov [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Bernstein, A.; Bowden, N.S. [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Cabrera-Palmer, B. [Sandia Livermore National Laboratories, Livermore, CA 94550 (United States); Ho, A.; Jonkmans, G. [Atomic Energy of Canada, Limited, Chalk River Laboratories, Chalk River, ON (Canada); Kogler, L.; Reyna, D. [Sandia Livermore National Laboratories, Livermore, CA 94550 (United States); Sur, B. [Atomic Energy of Canada, Limited, Chalk River Laboratories, Chalk River, ON (Canada)

    2015-01-21

    Here we present the development of a compact antineutrino detector for the purpose of nuclear reactor monitoring, improving upon a previously successful design. This paper will describe the design improvements of the detector which increases the antineutrino detection efficiency threefold over the previous effort. There are two main design improvements over previous generations of detectors for nuclear reactor monitoring: dual-ended optical readout and single volume detection mass. The dual-ended optical readout eliminates the need for fiducialization and increases the uniformity of the detector's optical response. The containment of the detection mass in a single active volume provides more target mass per detector footprint, a key design criteria for operating within a nuclear power plant. This technology could allow for real-time monitoring of the evolution of a nuclear reactor core, independent of reactor operator declarations of fuel inventories, and may be of interest to the safeguards community.

  20. Charged current neutrino and antineutrino interactions in hydrogen and deuterium

    International Nuclear Information System (INIS)

    In this dissertation results are presented of two different (anti-)neutrino experiments with the Big European Bubble Chamber (BEBC) filled with hydrogen and deuterium successively and exposed to the wide band (anti-)neutrino beam at the SPS at CERN. Chapter 1 contains the description of the experimental set-up and in chapter 2 results of the experiment with BEBC filled with deuterium and exposed to the antineutrino beam are presented. The multiplicity distributions of the charged hadron shower produced in (anti-)neutrino interactions with protons and neutrons are studied and compared with the results from hadron-hadron experiments. In chapter 3 a study of the exclusive reaction γp→μ-pπ+ is presented, data being obtained from an exposure of BEBC filled with hydrogen to the wide band neutrino beam. The absolute cross-section of the dominant subchannel γp→μ-Δ++(1232) averaged over an energy range of Esub(γ) = 20-200 GeV is measured to be sigma = (0.59 +- 0.06) . 10-38 cm2. This value is in good agreement with the results of other experiments. The differential cross-section dsigma/dQ2, the Δ++ decay angular distributions and the density matrix elements are determined. The value of the axial mass determined using the Schreiner-Von Hippel parametrization of the Adler model by fitting the total cross-section is Msub(A) = 0.85 +- 0.10 GeV/c2. (Auth.)

  1. The muon system of the Daya Bay Reactor antineutrino experiment

    OpenAIRE

    An, F. P.; Carr, R; McKeown, R.D.; Qian, X.; Tsang, R. H. M.

    2015-01-01

    The Daya Bay experiment consists of functionally identical antineutrino detectors immersed in pools of ultrapure water in three well-separated underground experimental halls near two nuclear reactor complexes. These pools serve both as shields against natural, low-energy radiation, and as water Cherenkov detectors that efficiently detect cosmic muons using arrays of photomultiplier tubes. Each pool is covered by a plane of resistive plate chambers as an additional means of detecting muons. De...

  2. Estimating terrestrial uranium and thorium by antineutrino flux measurements

    OpenAIRE

    Dye, Stephen T.; Guillian, Eugene H.

    2008-01-01

    Uranium and thorium within the Earth produce a major portion of terrestrial heat along with a measurable flux of electron antineutrinos. These elements are key components in geophysical and geochemical models. Their quantity and distribution drive the dynamics, define the thermal history, and are a consequence of the differentiation of the Earth. Knowledge of uranium and thorium concentrations in geological reservoirs relies largely on geochemical model calculations. This research report desc...

  3. Science Potential of a Deep Ocean Antineutrino Observatory

    OpenAIRE

    Dye, Steve

    2006-01-01

    This paper presents science potential of a deep ocean antineutrino observatory under development at Hawaii. The observatory design allows for relocation from one site to another. Positioning the observatory some 60 km distant from a nuclear reactor complex enables precision measurement of neutrino mixing parameters, leading to a determination of neutrino mass hierarchy. At a mid-Pacific location the observatory measures the flux and ratio of uranium and thorium decay neutrinos from earth's ma...

  4. Towards Earth AntineutRino TomograpHy (EARTH)

    OpenAIRE

    de Meijer, R. J.; Smit, F. D.; Brooks, F. D.; Fearick, R. W.; Woertche, H. J.; Mantovani, F

    2006-01-01

    The programme Earth AntineutRino TomograpHy (EARTH) proposes to build ten underground facilities each hosting a telescope. Each telescope consists of many detector modules, to map the radiogenic heat sources deep in the interior of the Earth by utilising direction sensitive geoneutrino detection. Recent hypotheses target the core-mantle boundary (CMB) as a major source of natural radionuclides and therefore of radiogenic heat. A typical scale of the processes that take place at the CMB is abo...

  5. Investigation of Large LGB Detectors for Antineutrino Detection

    OpenAIRE

    Nelson, P; Bowden, N. S.

    2011-01-01

    A detector material or configuration that can provide an unambiguous indication of neutron capture can substantially reduce random coincidence backgrounds in antineutrino detection and capture-gated neutron spectrometry applications. Here we investigate the performance of such a material, a composite of plastic scintillator and $^6$Li$_6^{nat}$Gd$(^{10}$BO$_{3})_{3}$:Ce (LGB) crystal shards of ~1 mm dimension and comprising 1% of the detector by mass. While it is found that the optical propag...

  6. Neutrino Geophysics at Baksan I: Possible Detection of Georeactor Antineutrinos

    International Nuclear Information System (INIS)

    J.M. Herndon in the 1990s proposed a natural nuclear fission georeactor at the center of the Earth with a power output of 3-10 TW as an energy source to sustain the Earth magnetic field. R.S. Raghavan in 2002 pointed out that, under certain conditions, antineutrinos generated in such a georeactor can be detected using massive scintillation detectors. We consider the underground Baksan Neutrino Observatory (4800 m w.e.) as a possible site for developments in geoneutrino physics. Here, the intrinsic background level of less than 1 event/yr in a liquid scintillation ∼1000-t target detector can be achieved and the main source of background is the antineutrino flux from power reactors. We find that this flux is ∼10 times lower than at the KamLAND detector site and two times lower than at the Gran Sasso laboratory and thus at Baksan the georeactor hypothesis can be conclusively tested. We also discuss possible searches for the composition of georeactor burning nuclear fuel by analysis of the antineutrino energy spectrum

  7. Neutrino Geophysics at Baksan I: Possible Detection of Georeactor Antineutrinos

    CERN Document Server

    Domogatski, G; Mikaelyan, L A; Sinev, V

    2004-01-01

    J.M. Herndon in 90-s proposed a natural nuclear fission georeactor at the center of the Earth with a power output of 3-10 TW as an energy source to sustain the Earth magnetic field. R.S. Raghavan in 2002 y. pointed out that under certain condition antineutrinos generated in georeactor can be detected using massive scintillation detectors. We consider the underground Baksan Neutrino Observatory (4800 m.w.e.) as a possible site for developments in Geoneutrino physics. Here the intrinsic background level of less than one event/year in a liquid scintillation ~1000 target ton detector can be achieved and the main source of background is the antineutrino flux from power reactors. We find that this flux is ~10 times lower than at KamLAND detector site and two times lower than at Gran Sasso laboratory and thus at Baksan the georeactor hypothesis can be conclusively tested. We also discuss possible search for composition of georector burning nuclear fuel by analysis of the antineutrino energy spectrum.

  8. The double chooz experiment: simulation of reactor antineutrino spectra

    International Nuclear Information System (INIS)

    The Double Chooz experiment aims to study the oscillations of electron antineutrinos produced by the Chooz nuclear power station, located in France, in the Ardennes region. It will lead to an unprecedented accuracy on the value of the mixing angle θ13. Improving the current knowledge on this parameter, given by the Chooz experiment, requires a reduction of both statistical and systematic errors, that is to say not only observing a large data sample, but also controlling the experimental uncertainties involved in the production and detection of electron antineutrinos. The use of two identical detectors will cancel most of the experimental systematic uncertainties limiting the sensitivity to the value of the mixing angle. We present in this thesis, simulations of reactor antineutrino spectra that were carried out in order to control the sources of systematic uncertainty related to the production of these particles by the plant. We also discuss our work on controlling the normalization error of the experiment through the precise determination of the number of target protons by a weighing measurement and through the study of the fiducial volume of the detectors which requires an accurate modeling of neutron physics. After three years of data taking with two detectors, Double Chooz will be able to disentangle an oscillation signal for sin22θ13 ≥ 0.05 (at 3σ) or, if no oscillations are observed, to put a limit of sin22θ13 ≤ 0.03 at 90% C.L. (author)

  9. Use of Antineutrino Detectors for Nuclear Reactor Safeguards Effectiveness Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Bernstein, A; Lambert, H E; Elayat, H A; O' Connell, W J; Rexroth, P; Baldwin, G; Bowden, N; Huelskamp, R

    2006-06-05

    As described in an earlier article [1], important information regarding reactor power and the amount and type of fissile material in reactor cores can be determined by measuring the antineutrino rate and energy spectrum, using a cubic meter scale antineutrino detector at tens of meters standoff from the core. Current International Atomic Energy Agency (IAEA) safeguards techniques do not provide such real-time quantitative information regarding core power levels and isotopic composition. The possible benefits of this approach are several and have been discussed in the earlier article. One key advantage is that the method gives the inspecting agency completely independent access to real-time information on the operational status and fissile content of the core. Furthermore, the unattended and non-intrusive nature of the technology may reduce the monitoring burden on the plant operator, even though more information is being provided than is available within the current IAEA safeguards regime. Here we present a detailed analytical framework for measuring the impact that such a detector might have on IAEA safeguards, if implemented. To perform the analysis, we will use initial data from our operating detector and a standard analysis technique for safeguards regimes, developed at Lawrence Livermore National Laboratory. Because characterization of the prototype detector is still underway, and because improvements in the prototype could have important impact on safeguards performance, the results presented here should be understood to be preliminary, and not reflective of the ultimate performance of the system. The structure of this paper is as follows. Reactor safeguards and the relevant properties of antineutrino detectors are briefly reviewed. A set of hypothetical diversion scenarios are then described, and one of these is analyzed using the Lawrence Livermore National Laboratory Integrated Safeguards System Analysis Tool (LISSAT) The probability of successful

  10. Antineutrino Neutral Current Interactions in MiniBooNE

    Energy Technology Data Exchange (ETDEWEB)

    Dharmapalan, Ranjan [Univ. of Alabama, Tuscaloosa, AL (United States)

    2012-01-01

    This dissertation reports the antineutrino-nucleus neutral current elastic scattering cross section on CH2 measured by the MiniBooNE experiment located in Batavia, IL. The data set consists of 60,605 events passing the selection cuts corresponding to 10.1×1020 POT, which represents the world’s largest sample of antineutrino neutral current elastic scattering events. The final sample is more than one order of magnitude lager that the previous antineutrino NCE scattering cross section measurement reported by the BNL E734 experiment. The measurement presented in this dissertation also spans a wider range in Q2, including the low-Q2 regime where the cross section rollover is clearly visible. A X2-based minimization was performed to determine the best value of the axial mass, MA and the Pauli blocking scaling function, that matches the antineutrino NCE scattering data. However, the best fit values of MA=1.29 GeV and K=1.026 still give a relatively poor X2, which suggests that the underlying nuclear model (based largely on the relativistic Fermi gas model) may not be an accurate representation for this particular interaction. Additionally, we present a measurement of the antineutrino/neutrino-nucleus NCE scattering cross section ratio. The neutrino mode NCE sample used in this study, corresponding to 6.4 × 1020 POT, is also the world’s largest sample (also by an order of magnitude). We have demonstrated that the ratio measurement is robust, as most of the correlated errors cancel, as expected. Furthermore, this ratio also proves to be rather insensitive to variations in the axial mass and the Pauli blocking parameter. This is the first time that this ratio has been experimentally reported. We believe this measurement will aid the theoretical physics community to test various model predictions of neutrino-nucleon/nucleus interactions.

  11. The upper limit of the solar antineutrino flux according to the LSD array data

    International Nuclear Information System (INIS)

    The analysis of the experimental data obtained at the LSD liquid scintillation detector is carried out with the aim of searching the possible flux of electron antineutrinos from Sun. The most strong at present upper limit for the electron antineutrino flux of solar origin is determined: ≤ 1.0 x 105 cm-2 x s-1 (the reliability level of 90%)

  12. Antineutrino Oscillations and a Search for Non-standard Interactions with the MINOS

    Energy Technology Data Exchange (ETDEWEB)

    Isvan, Zeynep [Univ. of Pittsburgh, PA (United States)

    2012-01-01

    MINOS searches for neutrino oscillations using the disappearance of muon neutrinos from the NuMI beam at Fermilab between two detectors. The Near Detector, located near the source, measures the beam composition before flavor change occurs. The energy spectrum is measured again at the Far Detector after neutrinos travel a distance. The mixing angle and mass splitting between the second and third mass states are extracted from the energy dependent difference between the spectra at the two detectors. NuMI is able to produce an antineutrino-enhanced beam as well as a neutrino-enhanced beam. Collecting data in antineutrino-mode allows the direct measurement of antineutrino oscillation parameters. From the analysis of the antineutrino mode data we measure $|\\Delta\\bar{m}^{2}_{\\text{atm}}| = 2.62^{+0.31}_{-0.28}\\times10^{-3}\\text{eV}^{2}$ and $\\sin^{2}(2\\bar{\\theta})_{23} = 0.95^{+0.10}_{-0.11}$, which is the most precise measurement of antineutrino oscillation parameters to date. A difference between neutrino and antineutrino oscillation parameters may indicate new physics involving interactions that are not part of the Standard Model, called non-standard interactions, that alter the apparent disappearance probability. Collecting data in neutrino and antineutrino mode independently allows a direct search for non-standard interactions. In this dissertation non-standard interactions are constrained by a combined analysis of neutrino and antineutrino datasets and no evidence of such interactions is found.

  13. A study of antineutrino spectra from spent nuclear fuel at Daya Bay

    Institute of Scientific and Technical Information of China (English)

    ZHOU Bin; RUAN Xi-Chao; NIE Yang-Bo; ZHOU Zu-Ying; AN Feng-Peng; CAO Jun

    2012-01-01

    The Daya Bay Reactor Antineutrino Experiment is designed to determine the as yet unknown neutrino mixing angle,θ13,by measuring the disappearance of electron antineutrinos from several nuclear reactor cores.The projected sensitivity in sin2(2θ13) of better than 0.01 at a 90% CL should be achieved after three years of data-taking.Antineutrinos emitted from spent nuclear fuel (SNF) distort the soft part of the energy spectrum.In this article,a calculation of the antineutrino spectra from the long-life isotopes in SNF is performed.A non-equilibrium generation of long half-life isotopes during the running time of the reactor is also analyzed.Finally,we show that the antineutrino event rate contribution from SNF,which has been stored in the SNF pool for several years,may be non-negligible.

  14. Nuclear security applications of antineutrino detectors : current capabilities and future prospects.

    Energy Technology Data Exchange (ETDEWEB)

    Bernstein, A.; Goodman, M.; Baldwin, G.; Learned, J.; Lund, J.; Reyna, D.; Svaboda, R. (High Energy Physics); (LLNL); (SNL); (LANL); (Univ. of Hawaii); (Univ. of California)

    2010-12-10

    Antineutrinos are electrically neutral, nearly massless fundamental particles produced in large numbers in the cores of nuclear reactors and in nuclear explosions. In the half century since their discovery, major advances in the understanding of their properties, and in detector technology, have opened the door to a new discipline - Applied Antineutrino Physics. Because antineutrinos are inextricably linked to the process of nuclear fission, there are many applications of interest in nuclear nonproliferation. This paper presents a comprehensive survey of applied antineutrino physics relevant for nonproliferation, summarizes recent advances in the field, describes the overlap of this nascent discipline with other ongoing fundamental and applied antineutrino research, and charts a course for research and development for future applications. It is intended as a resource for policymakers, researchers, and the wider nuclear nonproliferation community.

  15. A study of antineutrino spectra from spent nuclear fuel at Daya Bay

    International Nuclear Information System (INIS)

    The Daya Bay Reactor Antineutrino Experiment is designed to determine the as yet unknown neutrino mixing angle, θ13, by measuring the disappearance of electron antineutrinos from several nuclear reactor cores. The projected sensitivity in sin2 (2θ13) of better than 0.01 at a 90% CL should be achieved after three years of data-taking. Antineutrinos emitted from spent nuclear fuel (SNF) distort the soft part of the energy spectrum. In this article, a calculation of the antineutrino spectra from the long-life isotopes in SNF is performed. A non-equilibrium generation of long half-life isotopes during the running time of the reactor is also analyzed. Finally, we show that the antineutrino event rate contribution from SNF, which has been stored in the SNF pool for several years, may be non-negligible. (authors)

  16. Long-Term Testing and Properties of Acrylic for the Daya Bay Antineutrino Detectors

    CERN Document Server

    Krohn, M; Heeger, K M

    2012-01-01

    The Daya Bay reactor antineutrino experiment has recently measured the neutrino mixing parameter sin22{\\theta}13 by observing electron antineutrino disappearance over kilometer-scale baselines using six antineutrino detectors at near and far distances from reactor cores at the Daya Bay nuclear power complex. Liquid scintillator contained in transparent target vessels is used to detect electron antineutrinos via the inverse beta-decay reaction. The Daya Bay experiment will operate for about five years yielding a precision measurement of sin22{\\theta}13. We report on long-term studies of poly(methyl methacrylate) known as acrylic, which is the primary material used in the fabrication of the target vessels for the experiment's antineutrino detectors. In these studies, acrylic samples are subjected to gaseous and liquid environmental conditions similar to those experienced during construction, transport, and operation of the Daya Bay acrylic target vessels and detectors. Mechanical and optical stability of the ac...

  17. Dilepton and trilepton production by antineutrinos and neutrinos in neon

    Science.gov (United States)

    Gerbier, G.; Bertrand, D.; Guy, J.; Marage, P.; Aderholz, M.; Armenise, N.; Bartley, J. H.; Baton, J. P.; Brisson, V.; Belusevic, R.; Brou, D.; Bullock, F. W.; Calicchio, M.; Clayton, E. F.; Coghen, T.; Cooper-Sarkar, A. M.; Erriquez, O.; Fitch, P. J.; Hulth, P. O.; Jones, G. T.; Kasper, P.; Klein, H.; Kochowski, C.; Lagraa, M.; Leighton-Davis, S.; Middleton, R.; Miller, D. B.; Mobayyen, M. M.; Morrison, D. R. O.; Neveu, M.; Nuzzo, S.; O'Neale, S.; Parker, M. A.; Petiau, P.; Sacton, J.; Sansum, R. A.; Schmitz, N.; Simopoulou, E.; Talebzadeh, M.; Varvell, K.; Vallee, C.; Vayaki, A.; Venus, W.; Wachsmuth, H.; Wells, J.; Wittek, W.; Zevgolatakos, E.

    1985-03-01

    A sample of over 25,000 fully measured neutrino and antineutrino charged current interactions in BEBC includes 192 dilepton candidates. The prompt signal after subtraction of background is 41 ±7µ+ e -, 35±7µ+µ- events frombar v interactions, and 32±7µ-µ+ events from ν interactions. There are 2 trileptons, µ-µ- e + and µ-µ-µ+. Results are compared with other experimental data and with the standard model. Limits to prompt like sign µ+ e +, µ+µ+ and µ-µ- signals are given and compared with other experiments and with theoretical calculations.

  18. Dilepton and trilepton production by antineutrinos and neutrinos in neon

    International Nuclear Information System (INIS)

    A sample of over 25,000 fully measured neutrino and antineutrino charged current interactions in BEBC includes 192 dilepton candidates. The prompt signal after subtraction of background is 41+-7 μ+e-. 35+-7 μ+μ- events from anti ν interactions, and 32+-7μ- μ+ events from ν interactions. There are 2 trileptons, μ-μ- e+ and μ-μ-μ+. Results are compared with other experimental data and with the standard mode. Limits to prompt like sign μ+e+, μ+μ+ and μ-μ- signals are given and compared with other experiments and with theoretical calculations. (orig.)

  19. Neutrino Geophysics at Baksan I: Possible Detection of Georeactor Antineutrinos

    OpenAIRE

    Domogatski, G.; Kopeikin, V.; Mikaelyan, L.; Sinev, V.

    2004-01-01

    J.M. Herndon in 90-s proposed a natural nuclear fission georeactor at the center of the Earth with a power output of 3-10 TW as an energy source to sustain the Earth magnetic field. R.S. Raghavan in 2002 y. pointed out that under certain condition antineutrinos generated in georeactor can be detected using massive scintillation detectors. We consider the underground Baksan Neutrino Observatory (4800 m.w.e.) as a possible site for developments in Geoneutrino physics. Here the intrinsic backgro...

  20. Addendum: Neutrino Mass Hierarchy Determination Using Reactor Antineutrinos

    CERN Document Server

    Ghoshal, Pomita

    2012-01-01

    We update our study of neutrino mass hierarchy determination using a high statistics reactor electron anti-neutrino experiment in the light of the recent evidences of a relatively large non-zero value of \\theta_{13} from the Daya Bay and RENO experiments. We find that there are noticeable modifications in the results, which allow a relaxation in the detector's characteristics, such as the energy resolution and exposure, required to obtain a significant sensitivity to, or to determine, the neutrino mass hierarchy in such a reactor experiment.

  1. Science Potential of a Deep Ocean Antineutrino Observatory

    CERN Document Server

    Dye, S

    2007-01-01

    This paper presents science potential of a deep ocean antineutrino observatory under development at Hawaii. The observatory design allows for relocation from one site to another. Positioning the observatory some 60 km distant from a nuclear reactor complex enables precision measurement of neutrino mixing parameters, leading to a determination of neutrino mass hierarchy. At a mid-Pacific location the observatory measures the flux and ratio of uranium and thorium decay neutrinos from earth's mantle and performs a sensitive search for a hypothetical natural fission reactor in earth's core. A subsequent deployment at another mid-ocean location would test lateral heterogeneity of uranium and thorium in earth's mantle.

  2. Experimental Study Of Terrestrial Electron Anti-neutrinos With Kamland

    CERN Document Server

    Tolich, N R

    2005-01-01

    The analysis presented here uses Kamioka Liquid scintillator Anti-Neutrino Detector (KamLAND) to measure the rate of electron anti-neutrinos, ne&d1;' s , produced from terrestrial 238U and 212Th. 238U and 212Th are thought to be the main heat source driving mantle convection in the Earth, which in turn is responsible for plate tectonics. The total terrestrial 238U and 212Th content has been estimated from Earth models and rock samples from a very small fraction of the Earth. Until now there have been no direct measurements. Since ne&d1;' s have an exceedingly small cross section, they propagate undisturbed in the Earth interior, and their measurement near the Earth surface can be used to gain information on their sources. Based on a total of (2.63 ± 0.19) × 1031 target proton-years (0.506 kton- years), the 90% confidence interval for the total number of terrestrial 238U and 212Th ne&d1;' s detected is 4 to 40. This is consistent with the best models of terrestrial 23...

  3. Contribution of recently measured nuclear data to reactor antineutrino energy spectra predictions

    International Nuclear Information System (INIS)

    This paper attempts to summarize the actual problematic of reactor antineutrino energy spectra in the frame of fundamental and applied neutrino physics. Nuclear physics is an important ingredient of reactor antineutrino experiments. These experiments are motivated by neutrino oscillations, i.e. the measure of the θ13 mixing angle. In 2011, after a new computation of the reactor antineutrino energy spectra, based on the conversion of integral data of the beta spectra from 235U, and 239;241Pu, a deficit of reactor antineutrinos measured by short baseline experiments was pointed out. This is called the 'reactor anomaly', a new puzzle in the neutrino physics area. Since then, numerous new experimental neutrino projects have emerged. In parallel, computations of the antineutrino spectra independent from the ILL data would be desirable. One possibility is the use of the summation method, summing all the contributions of the fission product beta decay branches that can be found in nuclear databases. Studies have shown that in order to obtain reliable summation antineutrino energy spectra, new nuclear physics measurements of selected fission product beta decay properties are required. In these proceedings, we will present the computation methods of reactor antineutrino energy spectra and the impact of recent beta decay measurements on summation method spectra. The link of these nuclear physics studies with short baseline line oscillation search will be drawn and new neutrino physics projects at research reactors will be briefly presented. (authors)

  4. Contribution of recently measured nuclear data to reactor antineutrino energy spectra predictions

    Directory of Open Access Journals (Sweden)

    Fallot M.

    2013-12-01

    Full Text Available This paper attempts to summarize the actual problematic of reactor antineutrino energy spectra in the frame of fundamental and applied neutrino physics. Nuclear physics is an important ingredient of reactor antineutrino experiments. These experiments are motivated by neutrino oscillations, i.e. the measure of the θ13 mixing angle. In 2011, after a new computation of the reactor antineutrino energy spectra, based on the conversion of integral data of the beta spectra from 235U, and 239;241Pu, a deficit of reactor antineutrinos measured by short baseline experiments was pointed out. This is called the “reactor anomaly”, a new puzzle in the neutrino physics area. Since then, numerous new experimental neutrino projects have emerged. In parallel, computations of the antineutrino spectra independant from the ILL data would be desirable. One possibility is the use of the summation method, summing all the contributions of the fission product beta decay branches that can be found in nuclear databases. Studies have shown that in order to obtain reliable summation antineutrino energy spectra, new nuclear physics measurements of selected fission product beta decay properties are required. In these proceedings, we will present the computation methods of reactor antineutrino energy spectra and the impact of recent beta decay measurements on summation method spectra. The link of these nuclear physics studies with short baseline line oscillation search will be drawn and new neutrino physics projects at research reactors will be briefly presented.

  5. Neutrino and antineutrino inclusive charged-current cross section measurements with the MINOS near detector

    OpenAIRE

    Adamson, P.; Andreopoulos, C.; Arms, K. E.; Armstrong, R.; Auty, D. J.; Ayres, D. S.; Backhouse, C.; Barnes, JR; Barr, G.; Barrett, W. L.; Devenish, N. E.; Falk, E.; Harris, P.G.; Hartnell, J.; et al, ...

    2010-01-01

    The energy dependence of the neutrino-iron and antineutrino-iron inclusive charged-current cross sections and their ratio have been measured using a high-statistics sample with the MINOS Near Detector exposed to the NuMI beam from the Main Injector at Fermilab. Neutrino and antineutrino fluxes were determined using a low hadronic energy subsample of charged-current events. We report measurements of neutrino-Fe (antineutrinoFe) cross section in the energy range 3-50 GeV (5-50 GeV) with precisi...

  6. Can Radiogenic Heat Sources Inside the Earth be located by their Antineutrino incoming Directions?

    CERN Document Server

    Domogatsky, G; Mikaelyan, L; Sinev, V

    2004-01-01

    Antineutrinos born in the U and Th decay chains inside the Earth (``Geoneutrinos'') carry out information on the amount and distribution of radiogenic heat sources, which is of fundamental importance for geophysics. Models of the Earth distribute U and Th masses mainly between the continental crust and the lower mantle. It has been much discussed recently that a number of detectors stationed at appropriate geographical sites can separate the crust and mantle contributions. In present work we analyze directional separation of antineutrino signals arriving from the crust and the lower mantle with only one detector. We find that with a ~30-kton liquid scintillation antineutrino spectrometer using $\\bar{{\

  7. Search for Differences in Oscillation Parameters for Atmospheric Neutrinos and Antineutrinos at Super-Kamiokande

    CERN Document Server

    Abe, K; Iida, T; Ikeda, M; Iyogi, K; Kameda, J; Koshio, Y; Kozuma, Y; Miura, M; Moriyama, S; Nakahata, M; Nakayama, S; Obayashi, Y; Sekiya, H; Shiozawa, M; Suzuki, Y; Takeda, A; Takenaga, Y; Takeuchi, Y; Ueno, K; Ueshima, K; Watanabe, H; Yamada, S; Yokozawa, T; Ishihara, C; Kaji, H; Lee, K P; Kajita, T; Kaneyuki, K; McLachlan, T; Okumura, K; Shimizu, Y; Tanimoto, N; Martens, K; Vagins, M R; Labarga, L; Magro, L M; Dufour, F; Kearns, E; Litos, M; Raaf, J L; Stone, J L; Sulak, L R; Goldhaber, M; Bays, K; Kropp, W R; Mine, S; Regis, C; Smy, M B; Sobel, H W; Ganezer, K S; Hill, J; Keig, W E; Jang, J S; Kim, J Y; Lim, I T; Albert, J B; Scholberg, K; Walter, C W; Wendell, R; Wongjirad, T M; Tasaka, S; Learned, J G; Matsuno, S; Hasegawa, T; Ishida, T; Ishii, T; Kobayashi, T; Nakadaira, T; Nakamura, K; Nishikawa, K; Nishino, H; Oyama, Y; Sakashita, K; Sekiguchi, T; Tsukamoto, T; Suzuki, A T; Minamino, A; Nakaya, T; Fukuda, Y; Itow, Y; Mitsuka, G; Tanaka, T; Jung, C K; Taylor, I; Yanagisawa, C; Ishino, H; Kibayashi, A; Mino, S; Mori, T; Sakuda, M; Toyota, H; Kuno, Y; Kim, S B; Yang, B S; Ishizuka, T; Okazawa, H; Choi, Y; Nishijima, K; Koshiba, M; Yokoyama, M; Totsuka, Y; Chen, S; Heng, Y; Yang, Z; Zhang, H; Kielczewska, D; Mijakowski, P; Connolly, K; Dziomba, M; Wilkes, R J

    2011-01-01

    We present a search for differences in the oscillations of antineutrinos and neutrinos in the Super-Kamiokande -I, -II, and -III atmospheric neutrino sample. Under a two-flavor disappearance model with separate mixing parameters between neutrinos and antineutrinos, we find no evidence for a difference in oscillation parameters. Best fit antineutrino mixing is found to be at (dm2bar, sin2 2 thetabar) = (2.0x10^-3 eV^2, 1.0) and is consistent with the overall Super-K measurement.

  8. Decay heat and anti-neutrino energy spectra in fission fragments from total absorption spectroscopy

    Science.gov (United States)

    Rykaczewski, Krzysztof

    2015-10-01

    Decay studies of over forty 238U fission products have been studied using ORNL's Modular Total Absorption Spectrometer. The results are showing increased decay heat values, by 10% to 50%, and the energy spectra of anti-neutrinos shifted towards lower energies. The latter effect is resulting in a reduced number of anti-neutrinos interacting with matter, often by tens of percent per fission product. The results for several studied nuclei will be presented and their impact on decay heat pattern in power reactors and reactor anti-neutrino physics will be discussed.

  9. An Improved Measurement of Electron Antineutrino Disappearance at Daya Bay

    CERN Document Server

    Webber, David M

    2012-01-01

    The theory of neutrino oscillations explains changes in neutrino flavor, count rates, and spectra from solar, atmospheric, accelerator, and reactor neutrinos. These oscillations are characterized by three mixing angles and two mass-squared differences. The solar mixing angle, {\\theta}_12, and the atmospheric mixing angle, {\\theta}_23, have been well measured, but until recently the neutrino mixing angle {\\theta}_13 was not well known. The Daya Bay experiment, located northeast of Hong Kong at the Guangdong Nuclear Power Complex in China, has made a precise measurement of electron antineutrino disappearance using six functionally-identical gadolinium-doped liquid scintillator-based detectors at three sites with distances between 364 and 1900 meters from six reactor cores. This proceeding describes the Daya Bay updated result, using 127 days of good run time collected between December 24, 2011 and May 11, 2012. For the far site, the ratio of the observed number of events to the expected number of events assumin...

  10. Observation of Reactor Antineutrino Disappearance at RENO and Future Plan

    International Nuclear Information System (INIS)

    Reactor Experiment for Neutrino Oscillation (RENO) in South Korea observed electron anti-neutrino disappearance using data taken from August 2011 to March 2012 (about 222 live-days) at Yonggwang nuclear reactor site. The observed deficit resulted in measuring the last unknown neutrino mixing angle, sin22θ13, as 0.113 +/- 0.013 (stat) +/- 0.019 (sys.) which is 4.9 sigma level discovery over no oscillation hypothesis. We have taken about 440 live-days of data in total so far and those data are being analyzed. The ultimate goal of RENO analysis is that we would like to reduce statistical and systematic errors down to more than half of what are now by taking data for 3 years in total and by improving analysis method and reducing background. At the end, our future project, RENO-50, is discussed

  11. Quasielastic production of polarized hyperons in antineutrino--nucleon reactions

    CERN Document Server

    Akbar, F; Athar, M Sajjad; Singh, S K

    2016-01-01

    We have studied the longitudinal and perpendicular polarizations of final hyperon($\\Lambda$,$\\Sigma$) produced in the antineutrino induced quasielastic charged current reactions on nucleon targets. The nucleon-hyperon transition form factors are determined from the experimental data on quasielastic $(\\Delta S =0)$ charged current (anti)neutrino--nucleon scattering and the semileptonic decay of neutron and hyperons assuming G--invariance, T--invariance and SU(3) symmetry. The vector transition form factors are obtained in terms of nucleon electromagnetic form factors for which various parameterizations available in literature have been used. A dipole parameterization for the axial vector form factor and the pseudoscalar transition form factor derived in terms of axial vector form factor assuming PCAC and GT relation extended to strangeness sector have been used in numerical evaluations. The flux averaged cross section and polarization observables corresponding to CERN Gargamelle experiment have been calculated...

  12. Uncertainties analysis of fission fraction for reactor antineutrino experiments using DRAGON

    CERN Document Server

    Ma, X B; Chen, Y X; Zhong, W L; An, F P

    2014-01-01

    Rising interest in nuclear reactors as a source of antineutrinos for experiments motivates validated, fast, and accessible simulation to predict reactor rates. First, DRAGON was developed to calculate the fission rates of the four most important isotopes in fissions,235U,238U,239Pu and141Pu, and it was validated for PWRs using the Takahama benchmark. The fission fraction calculation function was validated through comparing our calculation results with MIT's results. we calculate the fission fraction of the Daya Bay reactor core, and compare its with those calculated by the commercial reactor simulation program SCIENCE, which is used by the Daya Bay nuclear power plant, and the results was consist with each other. The uncertainty of the antineutrino flux by the fission fraction was studied, and the uncertainty of the antineutrino flux by the fission fraction simulation is 0.6% per core for Daya Bay antineutrino experiment.

  13. Opportunities for applied measurements using the PROSPECT antineutrino detector: reactor physics and safeguards

    Science.gov (United States)

    Bowden, Nathaniel; Prospect Collaboration

    2015-10-01

    Disagreement of reactor antineutrino spectrum and flux measurements with updated predictions indicates that we have much to learn about the complicated processes underlying antineutrino production in reactors, as well as hinting at new physics. A number of new efforts seek to address these questions, including the PROSPECT experiment planned at the HFIR research reactor. In addition to greatly advancing our understanding of reactor antineutrino emissions, PROSPECT can support a rich applied physics program. The detection technology developed for PROSPECT will enable precision antineutrino spectrum measurements close to essentially any reactor type. Here we describe how such measurements provide opportunities to probe fissile isotope and fission daughter distributions, and their potential use for reactor physics and safeguards applications. LLNL-ABS-673983. Prepared by LLNL under Contract DE-AC52-07NA27344.

  14. The Daya Bay Antineutrino Detector Filling System and Liquid Mass Measurement

    CERN Document Server

    Band, H R; Draeger, E; Heeger, K M; Hinrichs, P; Lewis, C A; Mattison, H; McFarlane, M C; Webber, D M; Wenman, D; Wang, W; Wise, T; Xiao, Q

    2013-01-01

    The Daya Bay Reactor Neutrino Experiment has measured the neutrino mixing angle \\theta_{13} to world-leading precision. The experiment uses eight antineutrino detectors filled with 20-tons of gadolinium-doped liquid scintillator to detect antineutrinos emitted from the Daya Bay nuclear power plant through the inverse beta decay reaction. The precision measurement of sin^{2}2\\theta_{13} relies on the relative antineutrino interaction rates between detectors at near (400 m) and far (roughly 1.8 km) distances from the nuclear reactors. The measured interaction rate in each detector is directly proportional to the number of protons in the liquid scintillator target. A precision detector filling system was developed to simultaneously fill the three liquid zones of the antineutrino detectors and measure the relative target mass between detectors to <0.02%. This paper describes the design, operation, and performance of the system and the resulting precision measurement of the detectors' target liquid masses.

  15. A new approach to anti-neutrino running in long baseline neutrino oscillation experiments

    CERN Document Server

    Agarwalla, Sanjib K; Link, Jonathan M; Mohapatra, Debabrata

    2010-01-01

    We study the possibility to replace the anti-neutrino run of a long baseline neutrino oscillation experiment, with anti-neutrinos from muon decay at rest. The low energy of these neutrinos allows the use of inverse beta decay for detection in a Gadolinium-doped water Cerenkov detector. We show that this approach yields a factor of five times larger anti-neutrino event sample. The resulting discovery reaches in theta_13, the mass hierarchy and leptonic CP violation are compared with those from a conventional superbeam experiment with combined neutrino and anti-neutrino running. We find that this approach yields a greatly improved reach for CP violation and theta_13 while leaving the ability to measure the mass hierarchy intact.

  16. Above-ground antineutrino detection for nuclear reactor monitoring

    International Nuclear Information System (INIS)

    Antineutrino monitoring of nuclear reactors has been demonstrated many times (Klimov et al., 1994 [1]; Bowden et al., 2009 [2]; Oguri et al., 2014 [3]), however the technique has not as of yet been developed into a useful capability for treaty verification purposes. The most notable drawback is the current requirement that detectors be deployed underground, with at least several meters-water-equivalent of shielding from cosmic radiation. In addition, the deployment of liquid-based detection media presents a challenge in reactor facilities. We are currently developing a detector system that has the potential to operate above ground and circumvent deployment problems associated with a liquid detection media: the system is composed of segments of plastic scintillator surrounded by 6LiF/ZnS:Ag. ZnS:Ag is a radio-luminescent phosphor used to detect the neutron capture products of 6Li. Because of its long decay time compared to standard plastic scintillators, pulse-shape discrimination can be used to distinguish positron and neutron interactions resulting from the inverse beta decay (IBD) of antineutrinos within the detector volume, reducing both accidental and correlated backgrounds. Segmentation further reduces backgrounds by identifying the positron's annihilation gammas, a signature that is absent for most correlated and uncorrelated backgrounds. This work explores different configurations in order to maximize the size of the detector segments without reducing the intrinsic neutron detection efficiency. We believe that this technology will ultimately be applicable to potential safeguards scenarios such as those recently described by Huber et al. (2014) [4,5

  17. Study of charged current reactions induced by muon antineutrinos

    International Nuclear Information System (INIS)

    We present in this work a study of antineutrino reactions on light targets. We have used the Gargamelle cloud chamber with a propane-freon mix. In the 2 first chapters we give a brief description of the experimental setting and we present the selection criteria of the events. In the third chapter we analyse the data for the reaction anti-ν + p → μ+ + n that preserves strangeness. We have deduced the values of the axial (MA) and vector (MV) form factors: MA = (O.92 ± 0.08) GeV and MV = (0.86 ± 0.04) GeV. In the fourth chapter we study reactions in which strange particles appear (ΔS = 1) and we have determined their production cross-sections. The elastic reaction: anti-ν + p → μ+ + Λ is studied in a more accurate manner thanks to a 3-constraint adjustment that enables the selection of events occurring on free protons. We have deduced from our data the longitudinal, orthogonal and transverse polarization of Λ, we have got respectively Pl = -0.06 ± 0.44; Pp = 0.29 ± 0.41; Pt 1.05 ± 0.30. We have also deduced the values of the total cross-section as a function of the incident antineutrino energy E: σ (0.27 ± 0.02)*E*10-38 cm-2. E has been assessed from the energy deposited in the cloud chamber and we have adjusted the cross-section with a straight line as it is expected under the assumption of scale invariance. (A.C.)

  18. Remote safeguards and monitoring of reactors with antineutrinos.

    Energy Technology Data Exchange (ETDEWEB)

    Reyna, David

    2010-10-01

    The current state-of-the-art in antineutrino detection is such that it is now possible to remotely monitor the operational status, power levels and fissile content of nuclear reactors in real-time. This non-invasive and incorruptible technique has been demonstrated at civilian power reactors in both Russia and the United States and has been of interest to the IAEA Novel Technologies Unit for several years. Expert's meetings were convened at IAEA headquarters in 2003 and again in 2008. The latter produced a report in which antineutrino detection was called a 'highly promising technology for safeguards applications' at nuclear reactors and several near-term goals and suggested developments were identified to facilitate wider applicability. Over the last few years, we have been working to achieve some of these goals and improvements. Specifically, we have already demonstrated the successful operation of non-toxic detectors and most recently, we are testing a transportable, above-ground detector system, which is fully contained within a standard 6 meter ISO container. If successful, such a system could allow easy deployment at any reactor facility around the world. As well, our previously demonstrated ability to remotely monitor the data and respond in real-time to reactor operational changes could allow the verification of operator declarations without the need for costly site-visits. As the global nuclear power industry expands around the world, the burden on maintaining operational histories and safeguarding inventories will increase greatly. Such a system for providing remote data to verify operator's declarations could greatly reduce the need for frequent site inspections while still providing a robust warning of anomalies requiring further investigation.

  19. Above-ground antineutrino detection for nuclear reactor monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Sweany, M.; Brennan, J.; Cabrera-Palmer, B.; Kiff, S.; Reyna, D.; Throckmorton, D.

    2015-01-01

    Antineutrino monitoring of nuclear reactors has been demonstrated many times (Klimov et al., 1994 [1]; Bowden et al., 2009 [2]; Oguri et al., 2014 [3]), however the technique has not as of yet been developed into a useful capability for treaty verification purposes. The most notable drawback is the current requirement that detectors be deployed underground, with at least several meters-water-equivalent of shielding from cosmic radiation. In addition, the deployment of liquid-based detection media presents a challenge in reactor facilities. We are currently developing a detector system that has the potential to operate above ground and circumvent deployment problems associated with a liquid detection media: the system is composed of segments of plastic scintillator surrounded by {sup 6}LiF/ZnS:Ag. ZnS:Ag is a radio-luminescent phosphor used to detect the neutron capture products of {sup 6}Li. Because of its long decay time compared to standard plastic scintillators, pulse-shape discrimination can be used to distinguish positron and neutron interactions resulting from the inverse beta decay (IBD) of antineutrinos within the detector volume, reducing both accidental and correlated backgrounds. Segmentation further reduces backgrounds by identifying the positron's annihilation gammas, a signature that is absent for most correlated and uncorrelated backgrounds. This work explores different configurations in order to maximize the size of the detector segments without reducing the intrinsic neutron detection efficiency. We believe that this technology will ultimately be applicable to potential safeguards scenarios such as those recently described by Huber et al. (2014) [4,5].

  20. Remote safeguards and monitoring of reactors with antineutrinos.

    Energy Technology Data Exchange (ETDEWEB)

    Kiff, Scott D.; Dazeley, Steven (Lawrence Livermore National Laboratory, Livermore, CA); Reyna, David; Cabrera-Palmer, Belkis; Bernstein, Adam (Lawrence Livermore National Laboratory, Livermore, CA); Keefer, Greg (Lawrence Livermore National Laboratory, Livermore, CA); Bowden, Nathaniel S. (Lawrence Livermore National Laboratory, Livermore, CA)

    2010-09-01

    The current state-of-the-art in antineutrino detection is such that it is now possible to remotely monitor the operational status, power levels and fissile content of nuclear reactors in real-time. This non-invasive and incorruptible technique has been demonstrated at civilian power reactors in both Russia and the United States and has been of interest to the IAEA Novel Technologies Unit for several years. Expert's meetings were convened at IAEA headquarters in 2003 and again in 2008. The latter produced a report in which antineutrino detection was called a 'highly promising technology for safeguards applications' at nuclear reactors and several near-term goals and suggested developments were identified to facilitate wider applicability. Over the last few years, we have been working to achieve some of these goals and improvements. Specifically, we have already demonstrated the successful operation of non-toxic detectors and most recently, we are testing a transportable, above-ground detector system, which is fully contained within a standard 6 meter ISO container. If successful, such a system could allow easy deployment at any reactor facility around the world. As well, our previously demonstrated ability to remotely monitor the data and respond in real-time to reactor operational changes could allow the verification of operator declarations without the need for costly site-visits. As the global nuclear power industry expands around the world, the burden on maintaining operational histories and safeguarding inventories will increase greatly. Such a system for providing remote data to verify operator's declarations could greatly reduce the need for frequent site inspections while still providing a robust warning of anomalies requiring further investigation.

  1. Detection of reactor antineutrino coherent scattering off nuclei with a two-phase noble gas detector

    OpenAIRE

    Akimov, Dmitri; Bondar, Alexander; Burenkov, Alexander; Buzulutskov, Alexei

    2009-01-01

    Estimation of the signal amplitudes and counting rates for coherent scattering of reactor antineutrino off atomic nuclei in two-phase xenon and argon detectors has been done. A conceptual design of detector based on the existing technologies and experience has been proposed. It is shown that a condensed xenon/argon two-phase detector possesses the necessary sensitivity for the use in experiment on detection of coherent scattering of the reactor antineutrino off nuclei. It is shown that a two-...

  2. Search for Lorentz invariance and CPT violation with muon antineutrinos in the MINOS Near Detector

    OpenAIRE

    Adamson, P.; Ayres, D. S.; Barr, G.; Bishai, M.; Blake, A.; Bock, G.J.; Boehnlein, D. J.; Bogert, D.; Cao, S. V.; Cavanaugh, S.; Childress, S.; Coelho, J. A. B.; Corwin, L.; Cronin-Hennessy, D.; Danko, I. Z.

    2012-01-01

    We have searched for sidereal variations in the rate of antineutrino interactions in the MINOS Near Detector. Using antineutrinos produced by the NuMI beam, we find no statistically significant sidereal modulation in the rate. When this result is placed in the context of the Standard Model Extension theory we are able to place upper limits on the coefficients defining the theory. These limits are used in combination with the results from an earlier analysis of MINOS neutrino data to further c...

  3. Recoilless Resonance Absorption of Tritium Antineutrinos and Time-Energy Uncertainty Relation

    OpenAIRE

    Bilenky, S. M.

    2007-01-01

    We discuss neutrino oscillations in an experiment with M\\"ossbauer recoilless resonance absorbtion of tritium antineutrinos, proposed recently by Raghavan. We demonstrate that small energy uncertainty of antineutrinos which ensures a large resonance absorption cross section is in a conflict with the energy uncertainty which, according to the time-energy uncertainty relation, is necessary for neutrino oscillations to happen. The search for neutrino oscillations in the M\\"ossbauer neutrino expe...

  4. Experimental determination of differential cross-sections of muonic neutrinos and muonic antineutrinos interactions

    International Nuclear Information System (INIS)

    The experimental determination of muonic neutrinos and muonic antineutrinos differential cross-sections by the analysis of pictures taken in the CERN Gargamelle heavy liquid bubble chamber is presented. The methods used to solve experimental difficulties (muon identification, hadronic energy determination) and the errors on the experimental distributions are explained in detail. Then, the structure functions in charge changing interactions of neutrinos and antineutrinos are analyzed and interpreted in terms of parton distribution inside the nucleon

  5. KamLAND Bounds on Solar Antineutrinos and neutrino transition magnetic moments

    CERN Document Server

    Torrente-Lujan, E

    2003-01-01

    We investigate the possibility of detecting solar antineutrinos with the KamLAND experiment. These antineutrinos are predicted by spin-flavor oscillations at a significant rate even if this mechanism is not the leading solution to the SNP. The recent evidence from SNO shows that the solar flux could contain a residual component including sterile neutrinos and/or the antineutrinos of the active flavors. KamLAND is sensitive to antineutrinos originated from solar ${}^8$B neutrinos. From KamLAND negative results after 145 days of data taking, we obtain model independent limits on the total flux of solar antineutrinos $\\Phi({}^8 B)< 1.1-3.5\\times 10^4 cm^{-2} s^{-1}$, more than one order of magnitude smaller than existing limits,and on their appearance probability $P<0.15%$ (95% CL). Assuming a concrete model for antineutrino production by spin-flavor precession, this upper bound implies an upper limit on the product of the intrinsic neutrino magnetic moment and the value of the solar magnetic field $\\mu B&...

  6. Present status of sensitive detector of reactor’s antineutrinos using scintillating detectors

    Energy Technology Data Exchange (ETDEWEB)

    Fajt, L.; Mamedov, F.; Přidal, P.; Špavorová, M.; Štekl, I. [Institute of Experimental and Applied Physics, CTU in Prague (Czech Republic); Belov, V.; Egorov, V. G.; Fomina, M.; Kuznetsov, A.; Ponomarev, D.; Rozova, I.; Zhitnikov, I. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Burešová, H. [ENVINET a.s., Nuvia Group, Tǐebíč (Czech Republic)

    2015-08-17

    In 2011, the reanalysis of the reactor antineutrinos spectra led to the formulation of the Reactor Antineutrino Anomaly (RAA) [1], which indicates the discrepancy between measured and expected antineutrino fluxes on short baselines. This discrepancy appears to favor the existence of the fourth “sterile” neutrino with |Δm{sup 2}|>1 eV{sup 2}. To confirm or reject this hypothesis a high sensitive antineutrino detector located close to the reactor is required. In addition to that such a detector could be used to online monitor the isotopic composition of the reactor core and to prevent illegal production and removal of{sup 239}Pu, which is the essential part of nuclear weapons. Detector DANSSino [2] already proved that even a compact antineutrino detector (∼ 1 m{sup 3}) based on polystyrene is capable of antineutrino detection in the close vicinity of a reactor core (∼ 10 m) with signal to background ratio about one. As a common activity between JINR Dubna and IEAP CTU a new prototype of detector (called S{sup 3}) has been proposed and is under construction. The construction design, selected results of Monte Carlo simulations and results of benchmark tests are presented.

  7. Captures of hot and warm sterile antineutrino dark matter on EC-decaying {sup 63}Ho nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Li, Y.F.; Xing, Zhi-zhong, E-mail: liyufeng@ihep.ac.cn, E-mail: xingzz@ihep.ac.cn [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)

    2011-08-01

    Capturing low-energy electron antineutrinos on radioactive {sup 163}Ho nuclei, which decay into {sup 163}Dy via electron capture (EC), is a noteworthy opportunity to detect relic sterile antineutrinos. Such hypothetical particles are more or less implied by current experimental and cosmological data, and they might be a part of hot dark matter or a candidate for warm dark matter in the Universe. Using the isotope {sup 163}Ho as a target and assuming reasonable active-sterile antineutrino mixing angles, we calculate the capture rate of relic electron antineutrinos against the corresponding EC-decay background in the presence of sterile antineutrinos at the sub-eV or keV mass scale. We show that the signature of hot or warm sterile antineutrino dark matter should in principle be observable, provided the target is big enough and the energy resolution is good enough.

  8. Search for electron antineutrinos associated with gravitational wave events GW150914 and GW151226 using KamLAND

    CERN Document Server

    Gando, A; Hachiya, T; Hayashi, A; Hayashida, S; Ikeda, H; Inoue, K; Ishidoshiro, K; Karino, Y; Koga, M; Matsuda, S; Mitsui, T; Nakamura, K; Obara, S; Oura, T; Ozaki, H; Shimizu, I; Shirahata, Y; Shirai, J; Suzuki, A; Takai, T; Tamae, K; Teraoka, Y; Ueshima, K; Watanabe, H; Kozolov, A; Takemoto, Y; Yoshida, S; Fushimi, K; Piepke, A; Banks, T I; Berger, B E; Fujikawa, B K; O'Donnell, T; Learned, J G; Maricic, J; Sakai, M; Winslow, L A; Krupczak, E; Ouellet, J; Efremenko, Y; Karwowski, H J; Markoff, D M; Tornow, W; Detwiler, J A; Enomoto, S; Decowski, M P

    2016-01-01

    We present a search for low energy antineutrino events coincident with the gravitational wave events GW150914 and GW151226, and the candidate event LVT151012 using KamLAND, a kiloton-scale antineutrino detector. We find no inverse beta-decay neutrino events within $\\pm 500$ seconds of either gravitational wave signal. This non-detection is used to constrain the electron antineutrino fluence and the luminosity of the astrophysical sources.

  9. Towards Earth AntineutRino TomograpHy (EARTH)

    CERN Document Server

    De Meijer, R J; Fearick, R W; Mantovani, F; Smit, F D; Wörtche, H J

    2006-01-01

    The programme Earth AntineutRino TomograpHy (EARTH) proposes to build ten underground facilities each hosting a telescope. Each telescope consists of many detector modules, to map the radiogenic heat sources deep in the interior of the Earth by utilising direction sensitive geoneutrino detection. Recent hypotheses target the core-mantle boundary (CMB) as a major source of natural radionuclides and therefore of radiogenic heat. A typical scale of the processes that take place at the CMB is about 200km. To observe these processes from the surface requires an angular resolution of about 3 degrees. EARTH aims at creating a high-resolution 3D-map of the radiogenic heat sources in the interior of the Earth. It will thereby contribute to a better understanding of a number of geophysical phenomena observed at the surface of the Earth. This condition requires a completely different approach from the monolithic detector systems as e.g. KamLAND. This paper presents, for such telescopes, the boundary conditions set by ph...

  10. Long-term testing and properties of acrylic for the Daya Bay antineutrino detectors

    Science.gov (United States)

    Krohn, M.; Littlejohn, B. R.; Heeger, K. M.

    2012-08-01

    The Daya Bay reactor antineutrino experiment has recently measured the neutrino mixing parameter sin22θ13 by observing electron antineutrino disappearance over kilometer-scale baselines using six antineutrino detectors at near and far distances from reactor cores at the Daya Bay nuclear power complex. Liquid scintillator contained in transparent target vessels is used to detect electron antineutrinos via the inverse beta-decay reaction. The Daya Bay experiment will operate for about five years yielding a precision measurement of sin22θ13. We report on long-term studies of poly(methyl methacrylate) known as acrylic, which is the primary material used in the fabrication of the target vessels for the experiment's antineutrino detectors. In these studies, acrylic samples are subjected to gaseous and liquid environmental conditions similar to those experienced during construction, transport, and operation of the Daya Bay acrylic target vessels and detectors. Mechanical and optical stability of the acrylic as well as its interaction with detector liquids is reported.

  11. Experimental determination of the antineutrino spectrum of the fission products of U238

    International Nuclear Information System (INIS)

    Accurate predictions of the antineutrino spectrum emitted by a nuclear reactor are of paramount importance for current and future reactor neutrino experiments. The antineutrinos are produced in the β - decays of the fission daughters of the four main fuel isotopes 235U, 238U, 239Pu, and 241Pu. One way to calculate the total anti νe - spectrum emitted by a fuel assembly is to experimentally determine the cumulative β-spectra emitted after fission of these four main fuel isotopes and to convert these into the corresponding anti νe-spectra. Three of the four spectra could already be determined in the 1980's, but only recently an experiment at the scientific neutron source FRM II in Garching could be performed to measure the anti νe-spectrum of 238U which contributes 10 % to the total antineutrino output of a standard PWR. With this spectrum, it is now possible to predict the antineutrino output of a reactor without the use of theoretical calculations for the contributing spectra. This talk describes the results of the experiment and discusses the impact on the current analysis of reactor neutrino experiments and the reactor antineutrino anomaly, which may give a hint on the possible existence of light sterile neutrinos.

  12. A search for low-energy neutrino and antineutrino signals correlated with gamma-ray bursts with Borexino

    CERN Document Server

    Agostini, M; Appel, S; Atroshchenko, V; Bellini, G; Benziger, J; Bick, D; Bonfini, G; Bravo, D; Caccianiga, B; Calaprice, F; Caminata, A; Carlini, M; Cavalcante, P; Chepurnov, A; Choi, K; D'Angelo, D; Davini, S; de Kerret, H; Derbin, A; Di Noto, L; Drachnev, I; Etenko, A; Fomenko, K; Franco, D; Gabriele, F; Galbiati, C; Ghiano, C; Giammarchi, M; Goeger-Neff, M; Goretti, A; Gromov, M; Hagner, C; Hungerford, E; Ianni, Aldo; Ianni, Andrea; Jany, A; Jedrzejczak, K; Jeschke, D; Kobychev, V; Korablev, D; Korga, G; Kryn, D; Laubenstein, M; Lehnert, B; Litvinovich, E; Lombardi, F; Lombardi, P; Ludhova, L; Lukyanchenko, G; Machulin, I; Manecki, S; Maneschg, W; Manuzio, G; Marcocci, S; Meroni, E; Meyer, M; Miramonti, L; Misiaszek, M; Montuschi, M; Mosteiro, P; Muratova, V; Neumair, B; Oberauer, L; Obolensky, M; Ortica, F; Pallavicini, M; Papp, L; Pocar, A; Ranucci, G; Razeto, A; Re, A; Romani, A; Roncin, R; Rossi, N; Scheonert, S; Semenov, D; Skorokhvatov, M; Smirnov, O; Sotnikov, A; Sukhotin, S; Suvorov, Y; Tartaglia, R; Testera, G; Thurn, J; Toropova, M; Unzhakov, E; Vishneva, A; Vogelaar, R B; von Feilitzsch, F; Wang, H; Weinz, S; Winter, J; Wojcik, M; Wurm, M; Yokley, Z; Zaimidoroga, O; Zavatarelli, S; Zuber, K; Zuzel, G

    2016-01-01

    A search for neutrino and antineutrino events correlated with 2,350 gamma-ray bursts (GRBs) is performed with Borexino data collected between December 2007 and November 2015. No statistically significant excess over background is observed. We look for electron antineutrinos ($\\bar{\

  13. Neutrino Geophysics at Baksan (Part II): Possible Studies of Antineutrino- and Radiogenic Heat Sources in Earth Interior

    OpenAIRE

    Domogatsky, G.; Kopeikin, V.; Mikaelyan, L.; Sinev, V.

    2004-01-01

    Antineutrinos born inside the Earth (``geoneutrinos'') carry out information of fundamental importance for understanding of the origin and evolution of our planet. We show that Baksan Neutrino Observatory is one of the best sites for detection and analysis of geoneutrinos using large liquid scintillation spectrometer. Also we present a short story of concept of Earth as antineutrino source (1960 - 2004 yy)

  14. aCORN: A Measurement of the Beta-Antineutrino Correlation in Neutron Decay

    Science.gov (United States)

    Jones, Gordon

    2015-10-01

    The aCORN experiment has measured the electron-antineutrino angular correlation coefficient (the ``a'' coefficient) in free neutron decay. aCORN uses the dependence of the recoil proton momentum on the opening angle between the electron and the neutrino to form an asymmetry. The apparatus accepts decays where the antineutrino is restricted to two momentum groups having equal solid angle. In this geometry, proton time of flight distinguishes between decays with a large or small opening angle between the electron and the antineutrino. The correlation coefficient is determined from the asymmetry between two branches of the time of flight spectrum. The asymmetry was measured on the NG-6 neutron beam at the NIST Center for Neutron Research (NCNR), and a subsequent measurement has been started on the higher flux NG-C beam. An overview of the method and systematic effects will be presented, including results from the NG-6 dataset. National Science Foundation.

  15. Antineutrino emission and gamma background characteristics from a thermal research reactor

    CERN Document Server

    Bui, V M; Fallot, M; Communeau, V; Cormon, S; Estienne, M; Lenoir, M; Peuvrel, N; Shiba, T; Cucoanes, A S; Elnimr, M; Martino, J; Onillon, A; Porta, A; Pronost, G; Remoto, A; Thiolliere, N; Yermia, F; Zakari-Issoufou, A -A

    2016-01-01

    The detailed understanding of the antineutrino emission from research reactors is mandatory for any high sensitivity experiments either for fundamental or applied neutrino physics, as well as a good control of the gamma and neutron backgrounds induced by the reactor operation. In this article, the antineutrino emission associated to a thermal research reactor: the OSIRIS reactor located in Saclay, France, is computed in a first part. The calculation is performed with the summation method, which sums all the contributions of the beta decay branches of the fission products, coupled for the first time with a complete core model of the OSIRIS reactor core. The MCNP Utility for Reactor Evolution code was used, allowing to take into account the contributions of all beta decayers in-core. This calculation is representative of the isotopic contributions to the antineutrino flux which can be found at research reactors with a standard 19.75\\% enrichment in $^{235}$U. In addition, the required off-equilibrium correction...

  16. A Possible Detection of the Cosmic Antineutrino Background in the Presence of Flavor Effects

    CERN Document Server

    Li, Y F

    2011-01-01

    Lusignoli and Vignati have recently pointed out that it is in principle possible to directly detect the cosmic antineutrino background by using the rather stable isotope holmium-163 as a target, which can decay into dysprosium-163 via electron capture (EC) with a very small energy release. In this paper we calculate the rate of the relic antineutrino capture on holmium-163 nuclei against the corresponding EC decay rate by taking account of different neutrino mass hierarchies and reasonable values of theta_13. We show that such flavor effects are appreciable and even important in some cases, and stress that a calorimetric measurement of the cosmic antineutrino background might be feasible in the future.

  17. Monitoring nuclear reactors with anti-neutrino detectors: the ANGRA project

    Energy Technology Data Exchange (ETDEWEB)

    Chimenti, Pietro; Leigui, Marcelo Augusto [UFABC - Universidade Federal do ABC. Rua Santa Adelia, 166. Bairro Bangu. Santo Andre - SP (Brazil); Anjos, Joao; Azzi, Gabriel; Rafael, Gama; Ademarlaudo, Barbosa; Lima, Herman; VAZ, Mario; Villar, Arthur [Centro Brasileiro de Pesquisas Fisicas - CBPF, Rua Dr. Xavier Sigaud, 150, Urca, Rio de Janeiro, RJ - 22290-180 (Brazil); Gonzales, Luis Fernando; Bezerra, Thiago; Kemp, Ernesto [Unicamp, State University of Campinas, Cidade Universitaria ' Zeferino Vaz' , Barao Geraldo - Campinas, Sao Paulo (Brazil); Nunokawa, Hiroshi [Department of Physics, Pontifical Catholic University - PUC, Rua Marques de Sao Vicente, 225, 22451-900 Gavea - Rio de Janeiro - RJ (Brazil); Guedes, Germano; Faria, Paulo Cesar [Universidade Estadual de Feira de Santana - UEFS, Avenida Transnordestina, Novo Horizonte (Brazil); Pepe, Iuri [Universidade Federal da Bahia - UFBA (Brazil)

    2010-07-01

    We describe the status of the ANGRA Project, aimed at developing an anti-neutrino detector for monitoring nuclear reactors. Indeed the detection of anti-neutrinos provides a unique handle for non-invasive measurements of the nuclear fuel. This kind of measurements are of deep interest for developing new safeguards tools which may help in nuclear non-proliferation programs. The ANGRA experiment, placed at about 30 m from the core of the 4 GW Brazilian nuclear power reactor ANGRA II, is based on a water Cherenkov detector with about one ton target mass. A few thousand antineutrino interactions per day are expected. The latest results from simulations and the status of the construction are presented. (authors)

  18. A search for neutrino-antineutrino mass inequality by means of sterile neutrino oscillometry

    Science.gov (United States)

    Smirnov, M. V.; Loo, K. K.; Novikov, Yu. N.; Trzaska, W. H.; Wurm, M.

    2015-11-01

    The investigation of the oscillation pattern induced by the sterile neutrinos might determine the oscillation parameters, and at the same time, allow to probe CPT symmetry in the leptonic sector through neutrino-antineutrino mass inequality. We propose to use a large scintillation detector like JUNO or LENA to detect electron neutrinos and electron antineutrinos from MCi electron capture or beta decay sources. Our calculations indicate that such an experiment is realistic and could be performed in parallel to the current research plans for JUNO and RENO. Requiring at least 5σ confidence level and assuming the values of the oscillation parameters indicated by the current global fit, we would be able to detect neutrino-antineutrino mass inequality of the order of 0.5% or larger, which would imply a signal of CPT anomalies.

  19. Neutrino and antineutrino charge-exchange reactions on 12C

    International Nuclear Information System (INIS)

    We extend the formalism of weak interaction processes, obtaining new expressions for the transition rates, which greatly facilitate numerical calculations, for both neutrino-nucleus reactions and muon capture. Explicit violation of the conserved vector current hypothesis by the Coulomb field, as well as development of a sum-rule approach for inclusive cross sections, has been worked out. We have done a thorough study of exclusive (ground-state) properties of 12B and 12N within the projected quasiparticle random phase approximation (PQRPA). Good agreement with experimental data achieved in this way put into evidence the limitations of the standard RPA and QRPA models, which come from the inability of the RPA to open the p3/2 shell and from the nonconservation of the number of particles in the QRPA. The inclusive neutrino/antineutrino (ν/ν-tilde) reactions 12C(ν,e-)12N and 12C(ν-tilde,e+)12B are calculated within both the PQRPA and the relativistic QRPA. It is found that (i) the magnitudes of the resulting cross sections are close to the sum-rule limit at low energy, but significantly smaller than this limit at high energies, for both ν and ν-tilde; (ii) they increase steadily when the size of the configuration space is augmented, particularly for ν/ν-tilde energies >200 MeV; and (iii) they converge for sufficiently large configuration space and final-state spin. The quasi-elastic 12C(ν,μ-)12N cross section recently measured in the MiniBooNE experiment is briefly discussed. We study the decomposition of the inclusive cross section based on the degree of forbiddenness of different multipoles. A few words are dedicated to the ν/ν-tilde-12C charge-exchange reactions related to astrophysical applications.

  20. A Experiment to Determine the Mass of the Electron Antineutrino.

    Science.gov (United States)

    Sur, Bhaskar

    The fact that neutrinos may have mass has attracted considerable attention in recent years both on the theoretical and experimental forefronts. The advent of Grand Unified Theories, the candidacy of neutrinos as dark matter, the proposed neutrino oscillation (and MSW effect) solution to the Solar Neutrino Puzzle and the observance of neutrinos from Supernova 1987A have further stimulated experimental efforts to directly probe neutrino masses by looking for dynamical effects. The technique of examining the end -point spectrum of Tritium beta-decay has long been used in this vein. The recent report of a positive electron antineutrino mass of 30 +/- 2 ev by the ITEP group in Moscow and the subsequent results from Los Alamos, Zurich and Japan which are in conflict with this value have stirred some controversy in this field. The present experiment uses a technique which is different from the usual magnetic-electrostatic analysis of the beta-spectrum employed by most groups--that of sperical electrostatic retarding field analysis. This method yields an integrated spectrum of the source and because of this and the large solid angle of acceptance of the spectrometer, the experiment yields very good statistics. Also the proposed source in this case is frozen T_2 for which the various correction factors can be estimated very accurately. The design, construction and testing of the spectrometer is described in detail in this dissertation as is the procedure used for fitting the data and calculating the correction factors to be applied to it. Due to a series of unfortunate accidents, the experiment has not yet been completed, but having proved that the intrinsic (point source) resolution is only 5 to 10 ev, the total efficiency about 2% and the background count rate about 20 counts per second, the experiment is expected to yield a mass limit of the order of 20 ev when run with a source of strength of about 30 milliCurie for a few days in the very near future.

  1. Reactor and Antineutrino Spectrum Calculations for the Double Chooz First Phase Results

    International Nuclear Information System (INIS)

    The Double Chooz reactor oscillation experiment is designed to search for a non-vanishing value of the mixing angle θ13. For the first phase of the experiment with only the far detector running, the reactor electron antineutrino flux is normalized via reactor simulation. For this first phase and from its last results, Double Chooz observed an evidence for a reactor electron antineutrino disappearance. In 227.93 days of far detector live time, we obtained sin22θ13=0.109±0.030(stat)±0.025(syst). This result excludes the no-oscillation hypothesis at 99.8% CL

  2. First test of Lorentz violation with a reactor-based antineutrino experiment

    International Nuclear Information System (INIS)

    We present a search for Lorentz violation with 8249 candidate electron antineutrino events taken by the Double Chooz experiment in 227.9 live days of running. This analysis, featuring a search for a sidereal time dependence of the events, is the first test of Lorentz invariance using a reactor-based antineutrino source. No sidereal variation is present in the data and the disappearance results are consistent with sidereal time independent oscillations. Under the Standard-Model Extension, we set the first limits on 14 Lorentz violating coefficients associated with transitions between electron and tau flavor, and set two competitive limits associated with transitions between electron and muon flavor. (authors)

  3. Antineutrino Background from Spent Fuel Storage in sensitive Searches for theta_13 at Reactors

    CERN Document Server

    Kopeikin, V; Sinev, V

    2004-01-01

    Sensitive searches for antineutrino oscillations in atmospheric mass parameter region much discussed in recent years are based on accurate comparison of the inverse beta decay positron spectra measured in two (or more) detectors, far and near, stationed e.g. at ~1000 m and ~100 m from the reactor(s). We show that antineutrinos emitted from the stored irradiated fuel can differently distort the soft part of positron spectra measured in the far and near detector and thus mimic (or hide) the oscillation signal

  4. Antineutrino Background from Spent Fuel Storage in sensitive Searches for theta_13 at Reactors

    OpenAIRE

    Kopeikin, V.; Mikaelyan, L.; Sinev, V.

    2004-01-01

    Sensitive searches for antineutrino oscillations in atmospheric mass parameter region much discussed in recent years are based on accurate comparison of the inverse beta decay positron spectra measured in two (or more) detectors, far and near, stationed e.g. at ~1000 m and ~100 m from the reactor(s). We show that antineutrinos emitted from the stored irradiated fuel can differently distort the soft part of positron spectra measured in the far and near detector and thus mimic (or hide) the osc...

  5. Experimental Determination of the Antineutrino Spectrum of the Fission Products of $^{238}$U

    CERN Document Server

    Haag, N; Hofmann, M; Oberauer, L; Potzel, W; Schreckenbach, K; Wagner, F M

    2013-01-01

    An experiment was performed at the scientific neutron source FRM II in Garching to determine the cumulative antineutrino spectrum of the fission products of $^{238}$U. This was achieved by irradiating target foils of natural uranium with a thermal and a fast neutron beam and recording the emitted $\\beta$-spectra with a gamma-suppressing electron-telescope. The obtained $\\beta$-spectrum of the fission products of $^{235}$U was normalized to the data of the magnetic spectrometer BILL of $^{235}$U. This method strongly reduces systematic errors in the $^{238}$U measurement. The $\\beta$-spectrum of $^{238}$U was converted into the corresponding antineutrino spectrum. The final $\\bar\

  6. First Test of Lorentz Violation with a Reactor-based Antineutrino Experiment

    CERN Document Server

    Abe, Y; Anjos, J C dos; Bergevin, M; Bernstein, A; Bezerra, T J C; Bezrukhov, L; Blucher, E; Bowden, N S; Buck, C; Busenitz, J; Cabrera, A; Caden, E; Camilleri, L; Carr, R; Cerrada, M; Chang, P -J; Chimenti, P; Classen, T; Collin, A P; Conover, E; Conrad, J M; Crespo-Anadón, J I; Crum, K; Cucoanes, A; D'Agostino, M V; Damon, E; Dawson, J V; Dazeley, S; Dietrich, D; Djurcic, Z; Dracos, M; Durand, V; Ebert, J; Efremenko, Y; Elnimr, M; Erickson, A; Fallot, M; Fechner, M; von Feilitzsch, F; Felde, J; Fischer, V; Franco, D; Franke, A J; Franke, M; Furuta, H; Gama, R; Gil-Botella, I; Giot, L; Göger-Neff, M; Gonzalez, L F G; Goodman, M C; Goon, J TM; Greiner, D; Haag, N; Habib, S; Hagner, C; Hara, T; Hartmann, F X; Haser, J; Hatzikoutelis, A; Hayakawa, T; Hofmann, M; Horton-Smith, G A; Ishitsuka, M; Jochum, J; Jollet, C; Jones, C L; Kaether, F; Kalousis, L N; Kamyshkov, Y; Kaplan, D M; Katori, T; Kawasaki, T; Keefer, G; Kemp, E; de Kerret, H; Konno, T; Kryn, D; Kuze, M; Lachenmaier, T; Lane, C E; Lasserre, T; Letourneau, A; Lhuillier, D; Lima, H P; Lindner, M; López-Castanõ, J M; LoSecco, J M; Lubsandorzhiev, B K; Lucht, S; McKee, D; Maeda, J; Maesano, C N; Mariani, C; Maricic, J; Martino, J; Matsubara, T; Mention, G; Meregaglia, A; Meyer, M; Miletic, T; Milincic, R; Miyata, H; Mueller, Th A; Nagasaka, Y; Nakajima, K; Novella, P; Obolensky, M; Oberauer, L; Onillon, A; Osborn, A; Ostrovskiy, I; Palomares, C; Pepe, I M; Perasso, S; Perrin, P; Pfahler, P; Porta, A; Potzel, W; Pronost, G; Reichenbacher, J; Reinhold, B; Remoto, A; Röhling, M; Roncin, R; Roth, S; Rybolt, B; Sakamoto, Y; Santorelli, R; Sato, F; Schönert, S; Schoppmann, S; Schwetz, T; Shaevitz, M H; Shrestha, D; Sida, J -L; Sinev, V; Skorokhvatov, M; Smith, E; Spitz, J; Stahl, A; Stancu, I; Stokes, L F F; Strait, M; Stüken, A; Suekane, F; Sukhotin, S; Sumiyoshi, T; Sun, Y; Terao, K; Tonazzo, A; Toups, M; Thi, H H Trinh; Valdiviesso, G; Veyssiere, C; Wagner, S; Watanabe, H; White, B; Wiebusch, C; Winslow, L; Worcester, M; Wurm, M; Yanovitch, E; Yermia, F; Zimmer, V

    2012-01-01

    We present a search for Lorentz violation with 8249 candidate electron antineutrino events taken by the Double Chooz experiment in 227.9 live days of running. This analysis, featuring a search for a sidereal time dependence of the events, is the first test of Lorentz invariance using a reactor-based antineutrino source. No sidereal variation is present in the data and the disappearance results are consistent with sidereal time independent oscillations. Under the Standard-Model Extension (SME), we set the first limits on fourteen Lorentz violating coefficients associated with transitions between electron and tau flavor, and set two competitive limits associated with transitions between electron and muon flavor.

  7. Large scale Gd-beta-diketonate based organic liquid scintillator production for antineutrino detection

    CERN Document Server

    Aberle, C; Gramlich, B; Hartmann, F X; Lindner, M; Schönert, S; Schwan, U; Wagner, S; Watanabe, H

    2011-01-01

    Over the course of several decades organic liquid scintillators form the basis for successful neutrino detectors. For electron antineutrino detection at nuclear reactor plants, gadolinium loaded liquid scintillators provide efficient background suppression. In the Double Chooz reactor antineutrino experiment a newly developed gadolinium-loaded scintillator is utilized for the first time. Its large scale production and characterization as well as the creation of an additional metalfree scintillator are presented. Both organic liquids are used in the inner part of the Double Chooz detectors.

  8. Nuclear effect study on nucleon structure functions, in comparison with antineutrino interactions on neon and deuterium

    International Nuclear Information System (INIS)

    We have studied the nuclear effects on high energy antineutrino charged current interactions by comparing the data which were taken in the Bubble Chamber BEBC filled with Neon and Deuterium. On the one hand, the study of nuclear reinteractions gave us the possibility to estimate the formation time of hadrons. On the other hand, the comparison of structure functions does not show any significant difference between Neon and Deuterium. Though this result does not contradict the effects observed with charged leptons by the EMC and SLAC experiments, it is strongly incompatible with certain theoretical interpretations which implied a stronger effect in antineutrino interactions

  9. Low Energy Antineutrino Detection Using Neutrino Capture on EC Decaying Nuclei

    CERN Document Server

    Cocco, Alfredo G; Messina, Marcello

    2009-01-01

    In this paper we present a study of the interaction of low energy electron antineutrino on nuclei that undergo electron capture. We show that the two corresponding crossed reactions have a sizeable cross section and are both suitable for detection of low energy antineutrino. However, only in case very specific conditions on the Q-value of the decay are met or significant improvements on the performances of ion storage rings are achieved, these reactions could be exploited in the future to address the long standing problem of a direct detection of Cosmological Neutrino Background.

  10. Precise measurement of neutrino and anti-neutrino differential cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Tzanov, M.; Naples, D.; Boyd, S.; McDonald, J.; Radescu, V.; Adams, T.; Alton, A.; Avvakumov, S.; deBarbaro, L.; deBarbaro, P.; Bernstein, R.H.; Bodek, A.; Bolton, T.; Brau, J.; Buchholz, D.; Budd, H.; Bugel, L.; Conrad, J.; Drucker, R.B.; Fleming, B.T.; Frey, R.; /Pittsburgh U. /Cincinnati U. /Columbia U. /Fermilab /Kansas State U. /Northwestern

    2005-09-01

    The NuTeV experiment at Fermilab has obtained a unique high statistics sample of neutrino and anti-neutrino interactions using its high-energy sign-selected beam. We present a measurement of the differential cross section for charged-current neutrino and anti-neutrino scattering from iron. Structure functions, F{sub 2}(x,Q{sup 2}) and xF{sub 3}(x,Q{sup 2}), are determined by fitting the inelasticity, y, dependence of the cross sections. This measurement has significantly improved systematic precision as a consequence of more precise understanding of hadron and muon energy scales.

  11. Improved Measurement of the Reactor Antineutrino Flux and Spectrum at Daya Bay

    CERN Document Server

    An, F P; Band, H R; Bishai, M; Blyth, S; Cao, D; Cao, G F; Cao, J; Cen, W R; Chan, Y L; Chang, J F; Chang, L C; Chang, Y; Chen, H S; Chen, Q Y; Chen, S M; Chen, Y X; Chen, Y; Cheng, J -H; Cheng, J; Cheng, Y P; Cheng, Z K; Cherwinka, J J; Chu, M C; Chukanov, A; Cummings, J P; de Arcos, J; Deng, Z Y; Ding, X F; Ding, Y Y; Diwan, M V; Dolgareva, M; Dove, J; Dwyer, D A; Edwards, W R; Gill, R; Gonchar, M; Gong, G H; Gong, H; Grassi, M; Gu, W Q; Guan, M Y; Guo, L; Guo, R P; Guo, X H; Guo, Z; Hackenburg, R W; Han, R; Hans, S; He, M; Heeger, K M; Heng, Y K; Higuera, A; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, T; Hu, W; Huang, E C; Huang, H X; Huang, X T; Huber, P; Huo, W; Hussain, G; Jaffe, D E; Jaffke, P; Jen, K L; Jetter, S; Ji, X P; Ji, X L; Jiao, J B; Johnson, R A; Joshi, J; Kang, L; Kettell, S H; Kohn, S; Kramer, M; Kwan, K K; Kwok, M W; Kwok, T; Langford, T J; Lau, K; Lebanowski, L; Lee, J; Lee, J H C; Lei, R T; Leitner, R; Li, C; Li, D J; Li, F; Li, G S; Li, Q J; Li, S; Li, S C; Li, W D; Li, X N; Li, Y F; Li, Z B; Liang, H; Lin, C J; Lin, G L; Lin, S; Lin, S K; Lin, Y -C; Ling, J J; Link, J M; Littenberg, L; Littlejohn, B R; Liu, D W; Liu, J L; Liu, J C; Loh, C W; Lu, C; Lu, H Q; Lu, J S; Luk, K B; Lv, Z; Ma, Q M; Ma, X Y; Ma, X B; Ma, Y Q; Malyshkin, Y; Caicedo, D A Martinez; McDonald, K T; McKeown, R D; Mitchell, I; Mooney, M; Nakajima, Y; Napolitano, J; Naumov, D; Naumova, E; Ngai, H Y; Ning, Z; Ochoa-Ricoux, J P; Olshevskiy, A; Pan, H -R; Park, J; Patton, S; Pec, V; Peng, J C; Pinsky, L; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Raper, N; Ren, J; Rosero, R; Roskovec, B; Ruan, X C; Steiner, H; Sun, G X; Sun, J L; Tang, W; Taychenachev, D; Treskov, K; Tsang, K V; Tull, C E; Viaux, N; Viren, B; Vorobel, V; Wang, C H; Wang, M; Wang, N Y; Wang, R G; Wang, W; Wang, X; Wang, Y F; Wang, Z; Wang, Z; Wang, Z M; Wei, H Y; Wen, L J; Whisnant, K; White, C G; Whitehead, L; Wise, T; Wong, H L H; Wong, S C F; Worcester, E; Wu, C -H; Wu, Q; Wu, W J; Xia, D M; Xia, J K; Xing, Z Z; Xu, J Y; Xu, J L; Xu, Y; Xue, T; Yang, C G; Yang, H; Yang, L; Yang, M S; Yang, M T; Ye, M; Ye, Z; Yeh, M; Young, B L; Yu, Z Y; Zeng, S; Zhan, L; Zhang, C; Zhang, H H; Zhang, J W; Zhang, Q M; Zhang, X T; Zhang, Y M; Zhang, Y X; Zhang, Y M; Zhang, Z J; Zhang, Z Y; Zhang, Z P; Zhao, J; Zhao, Q W; Zhao, Y B; Zhong, W L; Zhou, L; Zhou, N; Zhuang, H L; Zou, J H

    2016-01-01

    A new measurement of the reactor antineutrino flux and energy spectrum by the Daya Bay reactor neutrino experiment is reported. The antineutrinos were generated by six 2.9 GW$_{\\mathrm{th}}$ nuclear reactors and detected by eight antineutrino detectors deployed in two near (510~m and 560~m flux-weighted baselines) and one far (1580~m flux-weighted baseline) underground experimental halls. With 621 days of data, more than 1.2 million inverse beta decay (IBD) candidates were detected. The IBD yield in the eight detectors was measured, and the ratio of measured to predicted flux was found to be $0.946\\pm0.020$ ($0.992\\pm0.021$) for the Huber+Mueller (ILL+Vogel) model. A 2.9 $\\sigma$ deviation was found in the measured IBD positron energy spectrum compared to the predictions. In particular, an excess of events in the region of 4-6~MeV was found in the measured spectrum, with a local significance of 4.4 $\\sigma$. A reactor antineutrino spectrum weighted by the IBD cross section is extracted for model-independent p...

  12. Simulation results of liquid and plastic scintillator detectors for reactor antineutrino detection - A comparison

    Science.gov (United States)

    Kashyap, V. K. S.; Pant, L. M.; Mohanty, A. K.; Datar, V. M.

    2016-03-01

    A simulation study of two kinds of scintillation detectors has been done using GEANT4. We compare plastic scintillator and liquid scintillator based designs for detecting electron antineutrinos emitted from the core of reactors. The motivation for this study is to set up an experiment at the research reactor facility at BARC for very short baseline neutrino oscillation study and remote reactor monitoring.

  13. The Improved Measurement of Electron-antineutrino Disappearance at Daya Bay

    CERN Document Server

    Dwyer, Daniel A

    2013-01-01

    With 2.5x the previously reported exposure, the Daya Bay experiment has improved the measurement of the neutrino mixing parameter sin^2(2theta_13) = 0.089+-0.010(stat)+-0.005(syst). Reactor anti-neutrinos were produced by six 2.9 GW(th) commercial power reactors, and measured by six 20-ton target-mass detectors of identical design. A total of 234,217 anti-neutrino candidates were detected in 127 days of exposure. An anti-neutrino rate of 0.944+-0.007(stat)+-0.003(syst) was measured by three detectors at a flux-weighted average distance of 1648 m from the reactors, relative to two detectors at 470 m and one detector at 576 m. Detector design and depth underground limited the background to 5+-0.3% (far detectors) and 2+-0.2% (near detectors) of the candidate signals. The improved precision confirms the initial measurement of reactor anti-neutrino disappearance, and continues to be the most precise measurement of theta_13.

  14. The relativistic Green's function model in charged-current quasielastic neutrino and antineutrino scattering at MINER$\

    OpenAIRE

    Meucci, Andrea; Giusti, Carlotta

    2014-01-01

    The analysis of charged-current quasielastic neutrino and antineutrino-nucleus scattering cross sections requires relativistic theoretical descriptions also accounting for the role of final-state interactions. We compare the results of the relativistic Green's function model with the data recently published by the MINER$\

  15. Search for Time-Independent Lorentz Violation using Muon Neutrino to Muon Antineutrino Transitions in MINOS

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, P.; et al.

    2016-05-10

    Data from the MINOS experiment has been used to search for mixing between muon neutrinos and muon antineutrinos using a time-independent Lorentz-violating formalism derived from the Standard-Model Extension (SME). MINOS is uniquely capable of searching for muon neutrino-antineutrino mixing given its long baseline and ability to distinguish between neutrinos and antineutrinos on an event-by-event basis. Neutrino and antineutrino interactions were observed in the MINOS Near and Far Detectors from an exposure of 10.56$\\times10^{20}$ protons-on-target from the NuMI neutrino-optimized beam. No evidence was found for such transitions and new, highly stringent limits were placed on the SME coefficients governing them. We place the first limits on the SME parameters $(c_{L})^{TT}_{\\mu\\mu} $ and $(c_{L})^{TT}_{\\tau\\tau}$ at $-8.4\\times10^{-23} < (c_{L})^{TT}_{\\mu\\mu} < 8.0\\times10^{-23}$ and $-8.0\\times10^{-23} < (c_{L})^{TT}_{\\tau\\tau} < 8.4\\times10^{-23}$, and the world's best limits on the $\\tilde{g}^{ZT}_{\\mu\\overline{\\mu}}$ and $\\tilde{g}^{ZT}_{\\tau\\overline{\\tau}}$ parameters at $|\\tilde{g}^{ZT}_{\\mu\\overline{\\mu}}| < 3.3\\times 10^{-23}$ and $|\\tilde{g}^{ZT}_{\\tau\\overline{\\tau}}| < 3.3\\times 10^{-23}$, all limits quoted at $3\\sigma$.

  16. Neutrino and antineutrino inclusive charged-current cross section measurement with the MINOS near detector

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, Debdatta; /Pittsburgh U.

    2009-03-01

    This thesis presents the measurement of energy dependence of the neutrino-nucleon inclusive charged current cross section on an isoscalar target in the range 3-50 GeV for neutrinos and 5-50 GeV energy range for antineutrinos. The data set was collected with the MINOS Near Detector using the wide band NuMI beam at Fermilab. The size of the charged current sample is 1.94 x 10{sup 6} neutrino events and 1.60 x 10{sup 5} antineutrino events. The flux has been extracted using a low hadronic energy sub-sample of the charged current events. The energy dependence of the cross section is obtained by dividing the charged current sample with the extracted flux. The neutrino and antineutrino cross section exhibits a linear dependence on energy at high energy but shows deviations from linear behavior at low energy. We also present a measurement of the ratio of antineutrino to neutrino inclusive cross section.

  17. Measurements of atmospheric neutrinos and antineutrinos in the MINOS Far Detector

    CERN Document Server

    Adamson, P; Barr, G; Bishai, M; Blake, A S T; Bock, G J; Boehnlein, D J; Bogert, D; Cao, S V; Chapman, J D; Childress, S; Coelho, J A B; Corwin, L; Cronin-Hennessy, D; Danko, I Z; de Jong, J K; Devenish, N E; Diwan, M V; Escobar, C O; Evans, J J; Falk, E; Feldman, G J; Frohne, M V; Gallagher, H R; Gomes, R A; Goodman, M C; Gouffon, P; Graf, N; Gran, R; Grzelak, K; Habig, A; Hartnell, J; Hatcher, R; Himmel, A; Holin, A; Hylen, J; Irwin, G M; Isvan, Z; Jaffe, D E; James, C; Jensen, D; Kafka, T; Kasahara, S M S; Koizumi, G; Kopp, S; Kordosky, M; Kreymer, A; Lang, K; Ling, J; Litchfield, P J; Loiacono, L; Lucas, P; Mann, W A; Marshak, M L; Mathis, M; Mayer, N; Medeiros, M M; Mehdiyev, R; Meier, J R; Messier, M D; Miller, W H; Mishra, S R; Mitchell, J; Moore, C D; Mualem, L; Mufson, S; Musser, J; Naples, D; Nelson, J K; Newman, H B; Nichol, R J; Nowak, J A; Oliver, W P; Orchanian, M; Pahlka, R B; Paley, J; Patterson, R B; Pawloski, G; Phan-Budd, S; Plunkett, R K; Qiu, X; Radovic, A; Ratchford, J; Rebel, B; Rosenfeld, C; Rubin, H A; Sanchez, M C; Schneps, J; Schreckenberger, A; Schreiner, P; Sharma, R; Sousa, A; Speakman, B; Strait, M; Tagg, N; Talaga, R L; Thomas, J; Thomson, M A; Toner, R; Torretta, D; Tzanakos, G; Urheim, J; Vahle, P; Viren, B; Walding, J J; Weber, A; Webb, R C; White, C; Whitehead, L; Wojcicki, S G; Zhang, K; Zwaska, R

    2012-01-01

    This paper reports measurements of atmospheric neutrino and antineutrino interactions in the MINOS Far Detector, based on 2553 live-days (37.9 kton-years) of data. A total of 2072 candidate events are observed. These are separated into 905 contained-vertex muons and 466 neutrino-induced rock-muons, both produced by charged-current $\

  18. Simulation results of liquid and plastic scintillator detectors for reactor antineutrino detection - A comparison

    International Nuclear Information System (INIS)

    A simulation study of two kinds of scintillation detectors has been done using GEANT4. We compare plastic scintillator and liquid scintillator based designs for detecting electron antineutrinos emitted from the core of reactors. The motivation for this study is to set up an experiment at the research reactor facility at BARC for very short baseline neutrino oscillation study and remote reactor monitoring

  19. A new measurement of antineutrino oscillation with the full detector configuration at Daya Bay

    CERN Document Server

    An, F.P.; Band, H.R.; Bishai, M.; Blyth, S.; Butorov, I.; Cao, G.F.; Cao, J.; Cen, W.R.; Chan, Y.L.; Chang, J.F.; Chang, L.C.; Chang, Y.; Chen, H.S.; Chen, Q.Y.; Chen, S.M.; Chen, Y.X.; Chen, Y.; Cheng, J.H.; Cheng, J.; Cheng, Y.P.; Cherwinka, J.J.; Chu, M.C.; Cummings, J.P.; de Arcos, J.; Deng, Z.Y.; Ding, X.F.; Ding, Y.Y.; Diwan, M.V.; Draeger, E.; Dwyer, D.A.; Edwards, W.R.; Ely, S.R.; Gill, R.; Gonchar, M.; Gong, G.H.; Gong, H.; Grassi, M.; Gu, W.Q.; Guan, M.Y.; Guo, L.; Guo, X.H.; Hackenburg, R.W.; Han, R.; Hans, S.; He, M.; Heeger, K.M.; Heng, Y.K.; Hor, Y.K.; Hsiung, Y.B.; Hu, B.Z.; Hu, L.M.; Hu, L.J.; Hu, T.; Hu, W.; Huang, E.C.; Huang, H.X.; Huang, X.T.; Huber, P.; Hussain, G.; Jaffe, D.E.; Jaffke, P.; Jen, K.L.; Jetter, S.; Ji, X.P.; Ji, X.L.; Jiao, J.B.; Johnson, R.A.; Kang, L.; Kettell, S.H.; Kramer, M.; Kwan, K.K.; Kwok, M.W.; Kwok, T.; Langford, T.J.; Lau, K.; Lebanowski, L.; Lee, J.; Lei, R.T.; Leitner, R.; Leung, A.; Leung, J.K.C.; Lewis, C.A.; Li, D.J.; Li, F.; Li, G.S.; Li, Q.J.; Li, S.C.; Li, W.D.; Li, X.N.; Li, X.Q.; Li, Y.F.; Li, Z.B.; Liang, H.; Lin, C.J.; Lin, G.L.; Lin, P.Y.; Lin, S.K.; Ling, J.J.; Link, J.M.; Littenberg, L.; Littlejohn, B.R.; Liu, D.W.; Liu, H.; Liu, J.L.; Liu, J.C.; Liu, S.S.; Lu, C.; Lu, H.Q.; Lu, J.S.; Luk, K.B.; Ma, Q.M.; Ma, X.Y.; Ma, X.B.; Ma, Y.Q.; McDonald, K.T.; McKeown, R.D.; Meng, Y.; Mitchell, I.; Kebwaro, J.Monari; Nakajima, Y.; Napolitano, J.; Naumov, D.; Naumova, E.; Ngai, H.Y.; Ning, Z.; Ochoa-Ricoux, J.P.; Olshevski, A.; Patton, S.; Pec, V.; Peng, J.C.; Piilonen, L.E.; Pinsky, L.; Pun, C.S.J.; Qi, F.Z.; Qi, M.; Qian, X.; Raper, N.; Ren, B.; Ren, J.; Rosero, R.; Roskovec, B.; Ruan, X.C.; Shao, B.B.; Steiner, H.; Sun, G.X.; Sun, J.L.; Tang, W.; Themann, H.; Tsang, K.V.; Tull, C.E.; Tung, Y.C.; Viaux, N.; Viren, B.; Vorobel, V.; Wang, C.H.; Wang, M.; Wang, N.Y.; Wang, R.G.; Wang, W.; Wang, W.W.; Wang, X.; Wang, Y.F.; Wang, Z.; Wang, Z.; Wang, Z.M.; Wei, H.Y.; Wen, L.J.; Whisnant, K.; White, C.G.; Whitehead, L.; Wise, T.; Wong, H.L.H.; Wong, S.C.F.; Worcester, E.; Wu, Q.; Xia, D.M.; Xia, J.K.; Xia, X.; Xing, Z.Z.; Xu, J.Y.; Xu, J.L.; Xu, J.; Xu, Y.; Xue, T.; Yan, J.; Yang, C.G.; Yang, L.; Yang, M.S.; Yang, M.T.; Ye, M.; Yeh, M.; Yeh, Y.S.; Young, B.L.; Yu, G.Y.; Yu, Z.Y.; Zang, S.L.; Zhan, L.; Zhang, C.; Zhang, H.H.; Zhang, J.W.; Zhang, Q.M.; Zhang, Y.M.; Zhang, Y.X.; Zhang, Y.M.; Zhang, Z.J.; Zhang, Z.Y.; Zhang, Z.P.; Zhao, J.; Zhao, Q.W.; Zhao, Y.F.; Zhao, Y.B.; Zheng, L.; Zhong, W.L.; Zhou, L.; Zhou, N.; Zhuang, H.L.; Zou, J.H.

    2015-01-01

    We report a new measurement of electron antineutrino disappearance using the fully-constructed Daya Bay Reactor Neutrino Experiment. The final two of eight antineutrino detectors were installed in the summer of 2012. Including the 404 days of data collected from October 2012 to November 2013 resulted in a total exposure of 6.9$\\times$10$^5$ GW$_{\\rm th}$-ton-days, a 3.6 times increase over our previous results. Improvements in energy calibration limited variations between detectors to 0.2%. Removal of six $^{241}$Am-$^{13}$C radioactive calibration sources reduced the background by a factor of two for the detectors in the experimental hall furthest from the reactors. Direct prediction of the antineutrino signal in the far detectors based on the measurements in the near detectors explicitly minimized the dependence of the measurement on models of reactor antineutrino emission. The uncertainties in our estimates of $\\sin^{2}2\\theta_{13}$ and $|\\Delta m^2_{ee}|$ were halved as a result of these improvements. Ana...

  20. Measurement of the Reactor Antineutrino Flux and Spectrum at Daya Bay

    CERN Document Server

    An, F P; Band, H R; Bishai, M; Blyth, S; Butorov, I; Cao, D; Cao, G F; Cao, J; Cen, W R; Chan, Y L; Chang, J F; Chang, L C; Chang, Y; Chen, H S; Chen, Q Y; Chen, S M; Chen, Y X; Chen, Y; Cheng, J H; Cheng, J; Cheng, Y P; Cherwinka, J J; Chu, M C; Cummings, J P; de Arcos, J; Deng, Z Y; Ding, X F; Ding, Y Y; Diwan, M V; Dove, J; Draeger, E; Dwyer, D A; Edwards, W R; Ely, S R; Gill, R; Gonchar, M; Gong, G H; Gong, H; Grassi, M; Gu, W Q; Guan, M Y; Guo, L; Guo, X H; Hackenburg, R W; Han, R; Hans, S; He, M; Heeger, K M; Heng, Y K; Higuera, A; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, L M; Hu, L J; Hu, T; Hu, W; Huang, E C; Huang, H X; Huang, X T; Huber, P; Hussain, G; Jaffe, D E; Jaffke, P; Jen, K L; Jetter, S; Ji, X P; Ji, X L; Jiao, J B; Johnson, R A; Kang, L; Kettell, S H; Kohn, S; Kramer, M; Kwan, K K; Kwok, M W; Kwok, T; Langford, T J; Lau, K; Lebanowski, L; Lee, J; Lei, R T; Leitner, R; Leung, K Y; Leung, J K C; Lewis, C A; Li, D J; Li, F; Li, G S; Li, Q J; Li, S C; Li, W D; Li, X N; Li, X Q; Li, Y F; Li, Z B; Liang, H; Lin, C J; Lin, G L; Lin, P Y; Lin, S K; Ling, J J; Link, J M; Littenberg, L; Littlejohn, B R; Liu, D W; Liu, H; Liu, J L; Liu, J C; Liu, S S; Lu, C; Lu, H Q; Lu, J S; Luk, K B; Ma, Q M; Ma, X Y; Ma, X B; Ma, Y Q; Caicedo, D A Martinez; McDonald, K T; McKeown, R D; Meng, Y; Mitchell, I; Kebwaro, J Monari; Nakajima, Y; Napolitano, J; Naumov, D; Naumova, E; Ngai, H Y; Ning, Z; Ochoa-Ricoux, J P; Olshevski, A; Pan, H -R; Park, J; Patton, S; Pec, V; Peng, J C; Piilonen, L E; Pinsky, L; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Raper, N; Ren, B; Ren, J; Rosero, R; Roskovec, B; Ruan, X C; Shao, B B; Steiner, H; Sun, G X; Sun, J L; Tang, W; Taychenachev, D; Tsang, K V; Tull, C E; Tung, Y C; Viaux, N; Viren, B; Vorobel, V; Wang, C H; Wang, M; Wang, N Y; Wang, R G; Wang, W; Wang, W W; Wang, X; Wang, Y F; Wang, Z; Wang, Z M; Wei, H Y; Wen, L J; Whisnant, K; White, C G; Whitehead, L; Wise, T; Wong, H L H; Wong, S C F; Worcester, E; Wu, Q; Xia, D M; Xia, J K; Xia, X; Xing, Z Z; Xu, J Y; Xu, J L; Xu, J; Xu, Y; Xue, T; Yan, J; Yang, C G; Yang, L; Yang, M S; Yang, M T; Ye, M; Yeh, M; Young, B L; Yu, G Y; Yu, Z Y; Zang, S L; Zhan, L; Zhang, C; Zhang, H H; Zhang, J W; Zhang, Q M; Zhang, Y M; Zhang, Y X; Zhang, Z J; Zhang, Z Y; Zhang, Z P; Zhao, J; Zhao, Q W; Zhao, Y F; Zhao, Y B; Zheng, L; Zhong, W L; Zhou, L; Zhou, N; Zhuang, H L; Zou, J H

    2015-01-01

    This Letter reports a measurement of the flux and energy spectrum of electron antineutrinos from six 2.9~GW$_{th}$ nuclear reactors with six detectors deployed in two near (effective baselines 512~m and 561~m) and one far (1,579~m) underground experimental halls in the Daya Bay experiment. Using 217 days of data, 296,721 and 41,589 inverse beta decay (IBD) candidates were detected in the near and far halls, respectively. The measured IBD yield is (1.55 $\\pm$ 0.04) $\\times$ 10$^{-18}$~cm$^2$/GW/day or (5.92 $\\pm$ 0.14) $\\times$ 10$^{-43}$~cm$^2$/fission. This flux measurement is consistent with previous short-baseline reactor antineutrino experiments and is $0.946\\pm0.022$ ($0.991\\pm0.023$) relative to the flux predicted with the Huber+Mueller (ILL+Vogel) fissile antineutrino model. The measured IBD positron energy spectrum deviates from both spectral predictions by more than 2$\\sigma$ over the full energy range with a local significance of up to $\\sim$4$\\sigma$ between 4-6 MeV. A reactor antineutrino spectrum...

  1. Search for time-independent Lorentz violation using muon neutrino to muon antineutrino transitions in MINOS

    CERN Document Server

    Adamson, P; Aurisano, A; Barr, G; Bishai, M; Blake, A; Bock, G J; Bogert, D; Cao, S V; Carroll, T J; Castromonte, C M; Chen, R; Childress, S; Coelho, J A B; Corwin, L; Cronin-Hennessy, D; de Jong, J K; de Rijck, S; Devan, A V; Devenish, N E; Diwan, M V; Escobar, C O; Evans, J J; Falk, E; Feldman, G J; Flanagan, W; Frohne, M V; Gabrielyan, M; Gallagher, H R; Germani, S; Gomes, R A; Goodman, M C; Gouffon, P; Graf, N; Gran, R; Grzelak, K; Habig, A; Hahn, S R; Hartnell, J; Hatcher, R; Holin, A; Huang, J; Hylen, J; Irwin, G M; Isvan, Z; James, C; Jensen, D; Kafka, T; Kasahara, S M S; Koizumi, G; Kordosky, M; Kreymer, A; Lang, K; Ling, J; Litchfield, P J; Lucas, P; Mann, W A; Marshak, M L; Mayer, N; McGivern, C; Medeiros, M M; Mehdiyev, R; Meier, J R; Messier, M D; Miller, W H; Mishra, S R; Sher, S Moed; Moore, C D; Mualem, L; Musser, J; Naples, D; Nelson, J K; Newman, H B; Nichol, R J; Nowak, J A; O'Connor, J; Orchanian, M; Pahlka, R B; Paley, J; Patterson, R B; Pawloski, G; Perch, A; Pfützner, M M; Phan, D D; Phan-Budd, S; Plunkett, R K; Poonthottathil, N; Qiu, X; Radovic, A; Rebel, B; Rosenfeld, C; Rubin, H A; Sail, P; Sanchez, M C; Schneps, J; Schreckenberger, A; Schreiner, P; Sharma, R; Sousa, A; Tagg, N; Talaga, R L; Thomas, J; Thomson, M A; Tian, X; Timmons, A; Todd, J; Tognini, S C; Toner, R; Torretta, D; Tzanakos, G; Urheim, J; Vahle, P; Viren, B; Weber, A; Webb, R C; White, C; Whitehead, L; Whitehead, L H; Wojcicki, S G; Zwaska, R

    2016-01-01

    Data from the MINOS experiment has been used to search for mixing between muon neutrinos and muon antineutrinos using a time-independent Lorentz-violating formalism derived from the Standard-Model Extension (SME). MINOS is uniquely capable of searching for muon neutrino-antineutrino mixing given its long baseline and ability to distinguish between neutrinos and antineutrinos on an event-by-event basis. Neutrino and antineutrino interactions were observed in the MINOS Near and Far Detectors from an exposure of 10.56$\\times10^{20}$ protons-on-target from the NuMI neutrino-optimized beam. No evidence was found for such transitions and new, highly stringent limits were placed on the SME coefficients governing them. We place the first limits on the SME parameters $(c_{L})^{TT}_{\\mu\\mu} $ and $(c_{L})^{TT}_{\\tau\\tau}$ at $-8.4\\times10^{-23} < (c_{L})^{TT}_{\\mu\\mu} < 8.0\\times10^{-23}$ and $-8.0\\times10^{-23} < (c_{L})^{TT}_{\\tau\\tau} < 8.4\\times10^{-23}$, and the world's best limits on the $\\tilde{g}^{Z...

  2. Hybrid method to resolve the neutrino mass hierarchy by supernova (anti)neutrino induced reactions

    Science.gov (United States)

    Vale, D.; Rauscher, T.; Paar, N.

    2016-02-01

    We introduce a hybrid method to determine the neutrino mass hierarchy by simultaneous measurements of responses of at least two detectors to antineutrino and neutrino fluxes from accretion and cooling phases of core-collapse supernovae. The (anti)neutrino-nucleus cross sections for 56Fe and 208Pb are calculated in the framework of the relativistic nuclear energy density functional and weak interaction Hamiltonian, while the cross sections for inelastic scattering on free protons p(bar nue,e+)n are obtained using heavy-baryon chiral perturbation theory. The modelling of (anti)neutrino fluxes emitted from a protoneutron star in a core-collapse supernova include collective and Mikheyev-Smirnov-Wolfenstein effects inside the exploding star. The particle emission rates from the elementary decay modes of the daughter nuclei are calculated for normal and inverted neutrino mass hierarchy. It is shown that simultaneous use of (anti)neutrino detectors with different target material allows to determine the neutrino mass hierarchy from the ratios of νe- and bar nue-induced particle emissions. This hybrid method favors neutrinos from the supernova cooling phase and the implementation of detectors with heavier target nuclei (208Pb) for the neutrino sector, while for antineutrinos the use of free protons in mineral oil or water is the appropriate choice.

  3. Total Absorption Spectroscopy of Fission Fragments Relevant for Reactor Antineutrino Spectra and Decay Heat Calculations

    Directory of Open Access Journals (Sweden)

    Porta A.

    2016-01-01

    Full Text Available Beta decay of fission products is at the origin of decay heat and antineutrino emission in nuclear reactors. Decay heat represents about 7% of the reactor power during operation and strongly impacts reactor safety. Reactor antineutrino detection is used in several fundamental neutrino physics experiments and it can also be used for reactor monitoring and non-proliferation purposes. 92,93Rb are two fission products of importance in reactor antineutrino spectra and decay heat, but their β-decay properties are not well known. New measurements of 92,93Rb β-decay properties have been performed at the IGISOL facility (Jyväskylä, Finland using Total Absorption Spectroscopy (TAS. TAS is complementary to techniques based on Germanium detectors. It implies the use of a calorimeter to measure the total gamma intensity de-exciting each level in the daughter nucleus providing a direct measurement of the beta feeding. In these proceedings we present preliminary results for 93Rb, our measured beta feedings for 92Rb and we show the impact of these results on reactor antineutrino spectra and decay heat calculations.

  4. Total Absorption Spectroscopy of Fission Fragments Relevant for Reactor Antineutrino Spectra and Decay Heat Calculations

    Science.gov (United States)

    Porta, A.; Zakari-Issoufou, A.-A.; Fallot, M.; Algora, A.; Tain, J. L.; Valencia, E.; Rice, S.; Bui, V. M.; Cormon, S.; Estienne, M.; Agramunt, J.; Äystö, J.; Bowry, M.; Briz, J. A.; Caballero-Folch, R.; Cano-Ott, D.; Cucouanes, A.; Elomaa, V.-V.; Eronen, T.; Estévez, E.; Farrelly, G. F.; Garcia, A. R.; Gelletly, W.; Gomez-Hornillos, M. B.; Gorlychev, V.; Hakala, J.; Jokinen, A.; Jordan, M. D.; Kankainen, A.; Karvonen, P.; Kolhinen, V. S.; Kondev, F. G.; Martinez, T.; Mendoza, E.; Molina, F.; Moore, I.; Perez-Cerdán, A. B.; Podolyák, Zs.; Penttilä, H.; Regan, P. H.; Reponen, M.; Rissanen, J.; Rubio, B.; Shiba, T.; Sonzogni, A. A.; Weber, C.

    2016-03-01

    Beta decay of fission products is at the origin of decay heat and antineutrino emission in nuclear reactors. Decay heat represents about 7% of the reactor power during operation and strongly impacts reactor safety. Reactor antineutrino detection is used in several fundamental neutrino physics experiments and it can also be used for reactor monitoring and non-proliferation purposes. 92,93Rb are two fission products of importance in reactor antineutrino spectra and decay heat, but their β-decay properties are not well known. New measurements of 92,93Rb β-decay properties have been performed at the IGISOL facility (Jyväskylä, Finland) using Total Absorption Spectroscopy (TAS). TAS is complementary to techniques based on Germanium detectors. It implies the use of a calorimeter to measure the total gamma intensity de-exciting each level in the daughter nucleus providing a direct measurement of the beta feeding. In these proceedings we present preliminary results for 93Rb, our measured beta feedings for 92Rb and we show the impact of these results on reactor antineutrino spectra and decay heat calculations.

  5. New Decay Data Sub-library for Calculation of Nuclear Reactors Antineutrino Spectra

    Science.gov (United States)

    Sonzogni, Alejandro; McCutchan, Elizabeth; Johnson, Timothy

    2015-10-01

    The ENDF/B-VII.1 decay data sub-library contains up-to-date decay properties for all known nuclides and can be used in a wide variety of applications such as decay heat, delayed nu-bar and astrophysics. We have recently completed an upgrade to the ENDF/B-VII.1 decay data sub-library in order to better calculate antineutrino spectra from fission of actinide nuclides. This sub-library has been used to identify the main contributors to the antineutrino spectra as well as to derive a systematic behavior of the energy integrated spectra similar to that of the beta-delayed neutron multiplicities. The main improvements have been the use of the TAGS data from Algora et al and Greenwood et al, as well as some of the single beta spectrum data from Rudstam et al to obtain beta minus level feedings. Additionally, we have calculated the antineutrino spectra for neutron energies higher than thermal, needed for highly-enriched uranium cores, such as the HFIR in ORNL that will be used in the PROSPECT experiment. These calculations are relevant since the high precision beta spectra which are used in many antineutrino calculations were measured at thermal energies. The impact of the fission yield data on these calculations will be discussed. This work was sponsored by the Office of Nuclear Physics, Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-98CH10886.

  6. First Measurement of the Muon Anti-Neutrino Charged Current Quasielastic Double-Differential Cross-Section

    Energy Technology Data Exchange (ETDEWEB)

    Grange, Joseph M. [Univ. of Florida, Gainesville, FL (United States)

    2013-01-01

    This dissertation presents the first measurement of the muon antineutrino charged current quasi-elastic double-differential cross section. These data significantly extend the knowledge of neutrino and antineutrino interactions in the GeV range, a region that has recently come under scrutiny due to a number of conflicting experimental results. To maximize the precision of this measurement, three novel techniques were employed to measure the neutrino background component of the data set. Representing the first measurements of the neutrino contribution to an accelerator-based antineutrino beam in the absence of a magnetic field, the successful execution of these techniques carry implications for current and future neutrino experiments.

  7. Energy dependence of total cross sections for neutrino and antineutrino interactions are energies below 35 GeV

    International Nuclear Information System (INIS)

    Further analysis of experimental data obtained in neutrino IHEP-ITEP experiment in Serpukhov is presented. Energy dependences of total cross sections for neutrino-nucleon and antineutrino-nucleon charged-current interactions in the energy range 5-35 GeV have been obtained. There is a tendency for a slow decrease of neutrino cross section with energy increase and a slope constancy of antineutrino cross section. It agrees well with QCD predictions

  8. Determination of the fission coefficients in thermal nuclear reactors for antineutrino detection

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Lenilson M. [Coordenacao dos Programas de Pos-Graduacao de Engenharia (PEN/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Cabral, Ronaldo G., E-mail: rgcabral@ime.eb.b [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil); Anjos, Joao C.C. dos, E-mail: janjos@cbpf.b [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil). Dept. GLN - G

    2011-07-01

    The nuclear reactors in operation periodically need to change their fuel. It is during this process that these reactors are more vulnerable to occurring of several situations of fuel diversion, thus the monitoring of the nuclear installations is indispensable to avoid events of this nature. Considering this fact, the most promissory technique to be used for the nuclear safeguard for the nonproliferation of nuclear weapons, it is based on the detection and spectroscopy of antineutrino from fissions that occur in the nuclear reactors. The detection and spectroscopy of antineutrino, they both depend on the single contribution for the total number of fission of each actinide in the core reactor, these contributions receive the name of fission coefficients. The goal of this research is to show the computational and mathematical modeling used to determinate these coefficients for PWR reactors. (author)

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

    CERN Document Server

    Li, Yu-Feng

    2014-01-01

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

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

    International Nuclear Information System (INIS)

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

  11. Target Mass Monitoring and Instrumentation in the Daya Bay Antineutrino Detectors

    CERN Document Server

    Band, Henry R; Greenler, Lee S; Heeger, Karsten M; Hinrichs, Paul; Kang, Li; Lewis, Christine; Li, Shanfeng; Lin, Shengxin; McFarlane, Michael C; Wang, Wei; Webber, David M; Wei, Yadong; Wise, Thomas; Xiao, Qiang; Yang, Li; Zhang, Zhijian

    2012-01-01

    The Daya Bay experiment measures sin^2 2{\\theta}_13 using functionally identical antineutrino detectors located at distances of 300 to 2000 meters from the Daya Bay nuclear power complex. Each detector consists of three nested fluid volumes surrounded by photomultiplier tubes. These volumes are coupled to overflow tanks on top of the detector to allow for thermal expansion of the liquid. Antineutrinos are detected through the inverse beta decay reaction on the proton-rich scintillator target. A precise and continuous measurement of the detector's central target mass is achieved by monitoring the the fluid level in the overflow tanks with cameras and ultrasonic and capacitive sensors. In addition, the monitoring system records detector temperature and levelness at multiple positions. This monitoring information allows the precise determination of the detectors' effective number of target protons during data taking. We present the design, calibration, installation and in-situ tests of the Daya Bay real-time ant...

  12. Measurement of antineutrino oscillation with the full detector configuration at Daya Bay

    CERN Document Server

    Grassi, Marco

    2016-01-01

    In this poster, we present the latest measurement of electron antineutrino disappearance using the fully constructed Daya Bay Reactor Neutrino Experiment. A total exposure of $6.9 \\times 10^5$ GW$_{\\mathrm{th}}$ ton days was achieved in November 2013 after 617 day of data taking. The most precise estimates to date of the neutrino mass and mixing parameters $|\\Delta \\mathrm{m}^2_{ee}|$ and $\\sin^2 2 \\theta_{13}$ were obtained with an analysis of the relative antineutrino rates and energy spectra between detectors. The value of the two parameters was found to be $\\sin^2 2 \\theta_{13} = 0.084 \\pm 0.005$ and $|\\Delta \\mathrm{m}^2_{ee}| = (2.42 \\pm 0.11) \\times 10^{-3}\\,\\mathrm{eV}^2$. This report focuses in particular on describing how improvements in the calibration and in the energy response model contributed to achieve this result.

  13. Quasielastic neutrino and antineutrino interaction at the Serpukhov accelerator (IHEP-ITEP collaboration)

    International Nuclear Information System (INIS)

    Preliminary results on the energy dependence of quasielastic differential and total cross-sections for neutrino and antineutrino scattering in the νsub(μ)n → μ-p and anti νsub(μ)p → μ+n interactions in the energy region 3 <= E <= 30 GeV obtined in the aluminium spark chamber detector are presented. The data are compared with the predictions of classical V-A theory with current vector conservation assumption. The best fit parameters for axial mass are Msub(A)=1.00+-0.07 and Msub(A)=1.04+-0.08 from the neutrino and antineutrino data respectively. It is shown that experimental data are in good agreement with the predictions of the standart V-A theory

  14. Search for Perturbations of Nuclear Decay Rates Induced by Reactor Electron Antineutrinos

    CERN Document Server

    Barnes, V E; Bryan, C D; Cinko, N; Deichert, G G; Gruenwald, J T; Heim, J M; Kaplan, H B; LaZur, R; Neff, D; Nistor, J M; Sahelijo, N; Fischbach, E

    2016-01-01

    We report the results of an experiment conducted near the High Flux Isotope Reactor of Oak Ridge National Laboratory, designed to address the question of whether a flux of reactor-generated electron antineutrinos can alter the rates of weak nuclear interaction-induced decays for Mn-54, Na-22, and Co-60. This experiment, while quite sensitive, cannot exclude perturbations less than one or two parts in $10^4$ in $\\beta$ decay (or electron capture) processes, in the presence of an antineutrino flux of $3\\times 10^{12}$ cm$^{-2}$ s$^{-1}$. The present experimental methods are applicable to a wide range of isotopes. Improved sensitivity in future experiments may be possible if we can understand and reduce the dominant systematic uncertainties.

  15. The Physics and Nuclear Nonproliferation Goals of WATCHMAN: A WAter CHerenkov Monitor for ANtineutrinos

    CERN Document Server

    Askins, M; Bernstein, A; Dazeley, S; Dye, S T; Handler, T; Hatzikoutelis, A; Hellfeld, D; Jaffke, P; Kamyshkov, Y; Land, B J; Learned, J G; Marleau, P; Mauger, C; Gann, G D Orebi; Roecker, C; Rountree, S D; Shokair, T M; Smy, M B; Svoboda, R; Sweany, M; Vagins, M R; van Bibber, K A; Vogelaar, R B; Wetstein, M J; Yeh, M

    2015-01-01

    This article describes the physics and nonproliferation goals of WATCHMAN, the WAter Cherenkov Monitor for ANtineutrinos. The baseline WATCHMAN design is a kiloton scale gadolinium-doped (Gd) light water Cherenkov detector, placed 13 kilometers from a civil nuclear reactor in the United States. In its first deployment phase, WATCHMAN will be used to remotely detect a change in the operational status of the reactor, providing a first- ever demonstration of the potential of large Gd-doped water detectors for remote reactor monitoring for future international nuclear nonproliferation applications. During its first phase, the detector will provide a critical large-scale test of the ability to tag neutrons and thus distinguish low energy electron neutrinos and antineutrinos. This would make WATCHMAN the only detector capable of providing both direction and flavor identification of supernova neutrinos. It would also be the third largest supernova detector, and the largest underground in the western hemisphere. In a...

  16. Method of Fission Product Beta Spectra Measurements for Predicting Reactor Anti-neutrino Emission

    OpenAIRE

    Asner, D. M.; Burns, K; Campbell, L. W.; Greenfield, B.; Kos, M. S.; Orrell, J. L.; Schram, M.; VanDevender, B.; Wood, L. S.; Wootan, D. W.

    2014-01-01

    The nuclear fission process that occurs in the core of nuclear reactors results in unstable, neutron rich fission products that subsequently beta decay and emit electron anti-neutrinos. These reactor neutrinos have served neutrino physics research from the initial discovery of the neutrino to current precision measurements of neutrino mixing angles. The prediction of the absolute flux and energy spectrum of the emitted reactor neutrinos hinges upon a series of seminal papers based on measurem...

  17. Hybrid method to resolve the neutrino mass hierarchy by supernova (anti)neutrino induced reactions

    CERN Document Server

    Vale, D; Paar, N

    2015-01-01

    We introduce a hybrid method to determine the neutrino mass hierarchy by simultaneous measurements of responses of at least two detectors to antineutrino and neutrino fluxes from accretion and cooling phases of core-collapse supernovae. The (anti)neutrino-nucleus cross sections for $^{56}$Fe and $^{208}$Pb are calculated in the framework of the relativistic nuclear energy density functional and weak interaction Hamiltonian, while the cross sections for inelastic scattering on free protons $\\mathrm{p}(\\bar{\

  18. Advances toward a transportable antineutrino detector system for reactor monitoring and safeguards

    Energy Technology Data Exchange (ETDEWEB)

    Reyna, D. [Sandia National Laboratories, Livermore, CA 94550 (United States); Bernstein, A. [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Lund, J.; Kiff, S.; Cabrera-Palmer, B. [Sandia National Laboratories, Livermore, CA 94550 (United States); Bowden, N. S.; Dazeley, S.; Keefer, G. [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States)

    2011-07-01

    Nuclear reactors have served as the neutrino source for many fundamental physics experiments. The techniques developed by these experiments make it possible to use these very weakly interacting particles for a practical purpose. The large flux of antineutrinos that leaves a reactor carries information about two quantities of interest for safeguards: the reactor power and fissile inventory. Our SNL/LLNL collaboration has demonstrated that such antineutrino based monitoring is feasible using a relatively small cubic meter scale liquid scintillator detector at tens of meters standoff from a commercial Pressurized Water Reactor (PWR). With little or no burden on the plant operator we have been able to remotely and automatically monitor the reactor operational status (on/off), power level, and fuel burnup. The initial detector was deployed in an underground gallery that lies directly under the containment dome of an operating PWR. The gallery is 25 meters from the reactor core center, is rarely accessed by plant personnel, and provides a muon-screening effect of some 20-30 meters of water equivalent earth and concrete overburden. Unfortunately, many reactor facilities do not contain an equivalent underground location. We have therefore attempted to construct a complete detector system which would be capable of operating in an aboveground location and could be transported to a reactor facility with relative ease. A standard 6-meter shipping container was used as our transportable laboratory - containing active and passive shielding components, the antineutrino detector and all electronics, as well as climate control systems. This aboveground system was deployed and tested at the San Onofre Nuclear Generating Station (SONGS) in southern California in 2010 and early 2011. We will first present an overview of the initial demonstrations of our below ground detector. Then we will describe the aboveground system and the technological developments of the two antineutrino

  19. Improved limit on the electron-antineutrino rest mass from tritium ß-decay

    OpenAIRE

    Weinheimer, Christian; Przyrembel, Michael; Backe, Hartmut; H. Barth; Bonn, Jochen; Degen, Beate; Edling, Thomas; Fischer, H.; Fleischmann, L.; Grooß, Jens-Uwe; Haid, R.; Hermanni, Antje; Kube, Gero; Leiderer, Paul; Loeken, Thomas

    1993-01-01

    The endpoint region of the β-spectrum of tritium was remeasured by an electrostatic spectrometer with magnetic guiding field. It enabled the search for a rest mass of the electron-antineutrino with improved precision. The result is m2v=−39±34stat±15syst(eV/c2)2, from which an upper limit of mv

  20. How Unequal Fluxes of High Energy Astrophysical Neutrinos and Antineutrinos can Fake New Physics

    CERN Document Server

    Nunokawa, Hiroshi; Funchal, Renata Zukanovich

    2016-01-01

    Flavor ratios of very high energy astrophysical neutrinos, which can be studied at the Earth by a neutrino telescope such as IceCube, can serve to diagnose their production mechanism at the astrophysical source. The flavor ratios for neutrinos and antineutrinos can be quite different as we do not know how they are produced in the astrophysical environment. Due to this uncertainty the neutrino and antineutrino flavor ratios at the Earth also could be quite different. Nonetheless, it is generally assumed that flavor ratios for neutrinos and antineutrinos are the same at the Earth, in fitting the high energy astrophysical neutrino data. This is a reasonable assumption for the limited statistics for the data we currently have. However, in the future the fit must be performed allowing for a possible discrepancy in these two fractions in order to be able to disentangle different production mechanisms at the source from new physics in the neutrino sector. To reinforce this issue, in this work we show that a wrong as...

  1. Supernova Relic Electron Neutrinos and anti-Neutrinos in future Large-scale Observatories

    CERN Document Server

    Volpe, C

    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 anti-neutrinos 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 electron neutrino and anti-neutrino fluxes and on the number of events for electron neutrinos on carbon, oxygen and argon, as well as electron anti-neutrinos on protons, 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 propert...

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

    International Nuclear Information System (INIS)

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

  3. Lithium antineutrino source in the tandem scheme of the accelerator and neutron producting tungsten target

    CERN Document Server

    Lyashuk, V I

    2016-01-01

    The antineutrinos of the neutron rich 8Li isotope is characterized by hard and good defined spectrum - averaged energy is 6.5 MeV and maximal - up to 13 MeV. An intensive antineutrino source with such parameters can be unique instrument for neutrino investigations and especially for search of sterile neutrinos. The 8Li can be produced by (n,gamma)-activation of 7Li isotope. The proposed scheme of the antineutrino source is based on the lithium blanket around the accelerator neutron producting target. We propose to use heavy water solution of the lithium hydroxide instead of lithium in metallic state. Such solution for lithium blanket substance ensure the large perspectives in real steps for creation of this installation. An analyses of neutron fields in the blanket and distribution of 8Li creation allows to propose the next principal steps in the construction of the lithium blanket. We propose to enclose the blanket volume isolating it's central part with more high 8Li production. This solution allows to decr...

  4. Inquiry into antineutrino angular distribution in the experiments on polarized neutron β-decay

    International Nuclear Information System (INIS)

    So far as γ-radiation unescapably accompanies β-decay and thereby the final state of neutron β-decay involves photon beside proton, electron and antineutrino, i.e., not three but four particles, the antineutrino kinematics cannot be reconstructed unambiguously when the proton and electron momenta are given only, the γ-radiation momenta being unknown. Consequently, in the experiments on the polarized neutron β-decay where the electron and proton momentum distributions are observed only, without registering the γ-radiation, the asymmetry factor B of the antineutrino angular distribution cannot be acquired rigorously, but the B value is to be estimated only on the average by drawing into consideration the expectation (mean) value and the dispersion ΔB. The correspondent unavoidable ambiguities in B attainment amount to several percent which is significant for the now-a-days experimental attempts to obtain the B value with the very high precision ∼ (0.1 - 1) %. With allowance for the electromagnetic interaction, experimental measurement of the electron and proton momentum distributions is seen also to be instructive to verify with high accuracy the gA value obtained previously from the electron angular distribution

  5. Upper limit on the cross section for reactor antineutrinos changing 22Na decay rates

    CERN Document Server

    de Meijer, R J

    2014-01-01

    In this paper we present results of a long-term observation of the decay of 22Na in the presence of a nuclear fission reactor. The measurements were made outside the containment wall of and underneath the Koeberg nuclear power plant near Cape Town, South Africa. Antineutrino fluxes ranged from ~5*10^11 to 1.6*10^13 cm^-2 s^-1 during this period. We show that the coincidence summing technique provides a sensitive tool to measure a change in the total decay constant as well as the branching ratio between EC and beta+ decay of 22Na to the first excited state in 22Ne. We observe a relative change in count rate between reactor-ON and reactor-OFF equal to (-0.51+/-0.11)*10^-4. After evaluating possible systematic uncertainties we conclude that the effect is either due to a hidden instrumental cause or due to an interaction between antineutrinos and the 22Na nucleus. An upper limit of ~0.03 barn has been deduced for observing any change in the decay rate of 22Na due to antineutrino interactions.

  6. Neutrino-antineutrino mass splitting in the Standard Model and baryogenesis

    CERN Document Server

    Fujikawa, Kazuo

    2014-01-01

    On the basis of a previously proposed mechanism of neutrino-antineutrino mass splitting in the Standard Model, which is Lorentz and $SU(2)\\times U(1)$ invariant but non-local to evade $CPT$ theorem, we discuss the possible implications of neutrino-antineutrino mass splitting on neutrino physics and baryogenesis. It is shown that non-locality within a distance scale of the Planck length, that may not be fatal to unitarity in generic effective theory, can generate the neutrino-antineutrino mass splitting of the order of observed neutrino mass differences, which is tested in oscillation experiments, and non-negligible baryon asymmetry depending on the estimate of sphaleron dynamics. The one-loop order induced electron-positron mass splitting in the Standard Model is shown to be finite and estimated at $\\sim 10^{-20}$ eV, well below the experimental bound $< 10^{-2}$ eV. The induced $CPT$ violation in the $K$-meson in the Standard Model is expected to be even smaller and well below the experimental bound $|m_{...

  7. Neutrino–antineutrino mass splitting in the Standard Model and baryogenesis

    Directory of Open Access Journals (Sweden)

    Kazuo Fujikawa

    2015-04-01

    Full Text Available On the basis of a previously proposed mechanism of neutrino–antineutrino mass splitting in the Standard Model, which is Lorentz and SU(2×U(1 invariant but non-local to evade the CPT theorem, we discuss the possible implications of neutrino–antineutrino mass splitting on neutrino physics and baryogenesis. It is shown that non-locality within a distance scale of the Planck length, that may not be fatal to unitarity in a generic effective theory, can generate the neutrino–antineutrino mass splitting of the order of the observed neutrino mass differences, which is tested in oscillation experiments, and a non-negligible baryon asymmetry depending on the estimate of sphaleron dynamics. The one-loop order induced electron–positron mass splitting in the Standard Model is shown to be finite and estimated at ∼10−20 eV, well below the experimental bound <10−2 eV. The induced CPT violation in the K-meson in the Standard Model is expected to be even smaller and well below the experimental bound |mK−mK¯|<0.44×10−18 GeV.

  8. Quasi-elastic interactions and one-pion production by neutrinos and anti-neutrinos on a deuterium target

    International Nuclear Information System (INIS)

    In this thesis, the weak charged current interactions of neutrinos and antineutrinos with nucleons are described, in which the neutrino scatters in a quasi-elastic way with the nucleon, leaving an excited nucleon state. The experiments have been performed in the bubble chamber BEBC, filled with deuterium and exposed to the CERN Wide Band (anti-)neutrino beams. This gave the opportunity to study both interactions on protons and on neutrons separately, whereas the measurement of the exclusive channels could be performed with a high precision. After a short introduction of the relevant theories (standard model; QCD; one-pion production models; FKR quark model), the experimental set-up at CERN is described as well as the bubble chamber picture facility in Amsterdam. Next, results of the neutrino and antineutrino experiments are given followed by a comparison with theory. (Auth.)

  9. Design and tests of a data acquisition system for the Angra anti-neutrinos detector

    International Nuclear Information System (INIS)

    Full text: We describe the design of a Data Acquisition System (DAQ) for the Angra antineutrino project, aimed at developing an antineutrino detector to monitor nuclear reactors through the detection of antineutrino counting rates and spectral measurements. The experiment, presently under construction, will take place at the Brazilian nuclear power plant Angra II and will detect antineutrinos generated in the fusion process of the nuclear reactor fuel. The DAQ system is designed to be able to digitize and to store all the analog signals coming from the photomultiplier tubes (PMT), after going through the front-end electronics. It is composed of VME standard electronic modules. We focus here on the design of a new VME data acquisition card (NDAQ), which will be part of the Angra DAQ. This card is composed of eight analog-to-digital channels (ADC), each one featuring 10 bits of vertical resolution and 125 MHz of sampling rate. In order to measure time between events, or between PMT pulses, an 82 ps resolution time-to-digital converter (TDC) is also included in the card. Other NDAQ features are: one 512K x 8 bits Static RAM for on-board data storage, reprogrammable data processing circuit (through the use of a Field Programmable Gate Array - FPGA), standalone operation (connecting to any computer via USB port) and a 512K x 32 bits output buffer, used to reduce dead time in the data flow. The card allows VME block read cycles, reaching the usual bandwidth of more than 20 MB/s. Considering the worst-case estimated event rate of 1kHz, comprising neutrino and muons events, the Angra project must be able to deal with 10 MB/s event rate, which is safely below the card bandwidth. The design uses off-the-shelf devices from worldwide semiconductor companies. A software framework for the DAQ is developed for Linux platforms by using standard scientific tools and languages like ROOT and C++. The NDAQ design is currently under tests. The design and preliminary results, using

  10. Neutrino mass bound in the standard scenario for supernova electronic antineutrino emission

    OpenAIRE

    Pagliaroli, Giulia; Rossi-Torres, Fernando; Vissani, Francesco

    2010-01-01

    Based on recent improvements of the supernova electron antineutrino emission model, we update the limit on neutrino mass from the SN1987A data collected by Kamiokande-II, IMB and Baksan. We derive the limit of 5.8 eV at 95 % CL, that we show to be remarkably insensitive to the astrophysical uncertainties. Also we evaluate the ultimate mass sensitivity of this method for a detector like Super-Kamiokande. We find that the bound lies in the sub-eV region, 0.8 eV at 95 % CL being a typical outcom...

  11. Terrestrial matter effects on reactor antineutrino oscillations at JUNO or RENO-50: how small is small?

    OpenAIRE

    Li, Yu-Feng; Wang, Yifang; Xing, Zhi-zhong

    2016-01-01

    We have carefully examined, in both analytical and numerical ways, how small the terrestrial matter effects can be in a given medium-baseline reactor antineutrino oscillation experiment like JUNO or RENO-50. Taking the ongoing JUNO experiment for example, we show that the inclusion of terrestrial matter effects may reduce the sensitivity of the neutrino mass ordering measurement by \\Delta \\chi^2_{\\rm MO} \\simeq 0.6, and a neglect of such effects may shift the best-fit values of the flavor mix...

  12. Recent Results of the Relativistic Green's Function Model in Quasielastic Neutrino and Antineutrino-Nucleus Scattering

    CERN Document Server

    Giusti, Carlotta

    2014-01-01

    The analysis of quasielastic neutrino and antineutrino-nucleus scattering cross sections requires relativistic theoretical descriptions also accounting for the role of final-state interactions (FSI). In the relativistic Green's function (RGF) model FSI are described by a complex optical potential where the imaginary part recovers the contribution of final-state channels that are not included in other models based on the impulse approximation. The RGF results are compared with the data recently published by the MiniBooNE and MINER$\

  13. An assessment of antineutrino detection as a tool for monitoring nuclear explosions

    Energy Technology Data Exchange (ETDEWEB)

    Adam Bernstein; Todd West; Vipin Gupta

    1999-06-01

    The antineutrino is the only real-time nuclear signature from a fission explosion that propagates great distances through air, water, and ground. The size and sensitivity of antineutrino detectors has increased dramatically in the last decade, and will continue to do so in the next, thanks in part to the renewed interest in neutrino physics brought on by the recent discovery that neutrinos may have mass. The evolution of antineutrino detectors, and the evident interest of the signature as a means for monitoring nuclear tests motivates this review of the capabilities of existing and possible future detectors as test ban verification tools. The authors find that existing liquid scintillator ionization detectors, operating a few tens of meters below the Earth's surface and containing a few thousand tons of active material, could be used to monitor an area of a few square kilometers for nuclear explosions at the 1 kt level. Purified water Cerenkov detectors of sizes comparable to existing detectors (50,000 m{sup 3}) could be used to detect 1 kt explosions at distances of a few tens of kilometers. If neutron-absorbing dopants such as sodium chloride or gadolinium could be added to purified water, the resulting background reduction would allow extension of the range for sensitivity to a pulse of 10 antineutrino events from a 1 kt explosion out to approximately 1000 km. Beyond 1000 km, backgrounds from the world's nuclear reactors would become prohibitively large. The engineering hurdles for such detectors would be formidable. The size of a doped detector operating at the 100 km range, suitable for cooperative monitoring of existing nuclear test sites, is about 60 times that of the largest existing water detector, and would require a factor of several dozen more photomultiplier tubes than what is now used in large scale physics experiments. At a price per phototube of $1000, capital costs would amount to several billions of dollars, even for a detector at this

  14. Further Evidence for the Decay K+ to pi+ neutrino-antineutrino

    CERN Document Server

    Adler, S; Bergbusch, P; Blackmore, E W; Bryman, D A; Chen, S; Chiang, I H; Diwan, M V; Frank, J S; Haggerty, J S; Hu, J; Inagaki, T; Ito, M; Jain, V; Kabe, S; Kettell, S H; Kitching, P; Kobayashi, M; Komatsubara, T K; Konaka, A; Kuno, Y; Kuriki, M; Li, K K; Littenberg, L S; MacDonald, J A; Meyers, P D; Mildenberger, J; Miyajima, M; Muramatsu, N; Nakano, T; Ng, C; Ng, S; Numao, T; Poutissou, J M; Poutissou, R; Redlinger, G; Sato, T; Shimada, K; Shimoyama, T; Shinkawa, T; Shoemaker, F C; Stone, J R; Strand, R C; Sugimoto, S; Tamagawa, Y; Witzig, C; Yoshimura, Y

    2002-01-01

    Additional evidence for the rare kaon decay K+ to pi+ neutrino-antineutrino has been found in a new data set with comparable sensitivity to the previously reported result. One new event was observed in the pion momentum region examined, 211

  15. Proposed Search for a Fourth Neutrino with a PBq Antineutrino Source

    International Nuclear Information System (INIS)

    Several observed anomalies in neutrino oscillation data can be explained by a hypothetical fourth neutrino separated from the three standard neutrinos by a squared mass difference of a few eV2. We show that this hypothesis can be tested with a PBq (ten kilocurie scale) 144Ce or 106Ru antineutrino beta source deployed at the center of a large low background liquid scintillator detector. In particular, the compact size of such a source could yield an energy-dependent oscillating pattern in event spatial distribution that would unambiguously determine neutrino mass differences and mixing angles.

  16. A side-by-side comparison of Daya Bay antineutrino detectors

    CERN Document Server

    An, F P; Bai, J Z; Balantekin, A B; Band, H R; Beriguete, W; Bishai, M; Blyth, S; Brown, R L; Cao, G F; Cao, J; Carr, R; Chang, J F; Chang, Y; Chasman, C; Chen, H S; Chen, S J; Chen, S M; Chen, X C; Chen, X H; Chen, X S; Chen, Y; Cherwinka, J J; Chu, M C; Cummings, J P; Deng, Z Y; Ding, Y Y; Diwan, M V; Draeger, E; Du, X F; Dwyer, D; Edwards, W R; Ely, S R; Fang, S D; Fu, J Y; Fu, Z W; Ge, L Q; Gill, R L; Gonchar, M; Gong, G H; Gong, H; Gornushkin, Y A; Greenler, L S; Gu, W Q; Guan, M Y; Guo, X H; Hackenburg, R W; Hahn, R L; Hans, S; Hao, H F; He, M; He, Q; He, W S; Heeger, K M; Heng, Y K; Hinrichs, P; Ho, T H; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, T; Hu, T; Huang, H X; Huang, H Z; Huang, P W; Huang, X; Huang, X T; Huber, P; Jaffe, D E; Jetter, S; Ji, X L; Ji, X P; Jiang, H J; Jiang, W Q; Jiao, J B; Johnson, R A; Kang, L; Kettell, S H; Kramer, M; Kwan, K K; Kwok, M W; Kwok, T; Lai, C Y; Lai, W C; Lai, W H; Lau, K; Lebanowski, L; Lee, M K P; Leitner, R; Leung, J K C; Leung, K Y; Lewis, C A; Li, F; Li, G S; Li, J; Li, Q J; Li, S F; Li, W D; Li, X B; Li, X N; Li, X Q; Li, Y; Li, Z B; Liang, H; Lin, C J; Lin, G L; Lin, S K; Lin, S X; Lin, Y C; Ling, J J; Link, J M; Littenberg, L; Littlejohn, B R; Liu, B J; Liu, D W; Liu, J C; Liu, J L; Liu, S; Liu, X; Liu, Y B; Lu, C; Lu, H Q; Luk, A; Luk, K B; Luo, X L; Ma, L H; Ma, Q M; Ma, X Y; Ma, Y Q; Mayes, B; McDonald, K T; McFarlane, M C; McKeown, R D; Meng, Y; Mohapatra, D; Nakajima, Y; Napolitano, J; Naumov, D; Nemchenok, I; Newsom, C; Ngai, H Y; Ngai, W K; Nie, Y B; Ning, Z; Ochoa-Ricoux, J P; Olshevski, A; Pagac, A; Patton, S; Pec, V; Peng, J C; Piilonen, L E; Pinsky, L; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Rosero, R; Roskovec, B; Ruan, X C; Seilhan, B; Shao, B B; Shih, K; Steiner, H; Stoler, P; Sun, G X; Sun, J L; Tam, Y H; Tanaka, H K; Tang, X; Torun, Y; Trentalange, S; Tsai, O; Tsang, K V; Tsang, R H M; Tull, C; Viren, B; Vorobel, V; Wang, C H; Wang, L S; Wang, L Y; Wang, M; Wang, N Y; Wang, R G; Wang, W; Wang, X; Wang, Y F; Wang, Z; Wang, Z; Wang, Z M; Webber, D M; Wei, Y D; Wen, L J; Wenman, D L; Whisnant, K; White, C G; Whitehead, L; Wilhelmi, J; Wise, T; Wong, H L H; Wong, J; Wu, F F; Wu, Q; Xi, J B; Xia, D M; Xiao, Q; Xing, Z Z; Xu, G; Xu, J; Xu, J; Xu, J L; Xu, Y; Xue, T; Yang, C G; Yang, L; Ye, M; Yeh, M; Yeh, Y S; Young, B L; Yu, Z Y; Zhan, L; Zhang, C; Zhang, F H; Zhang, J W; Zhang, Q M; Zhang, S H; Zhang, Y C; Zhang, Y H; Zhang, Y X; Zhang, Z J; Zhang, Z P; Zhang, Z Y; Zhao, H; Zhao, J; Zhao, Q W; Zhao, Y B; Zheng, L; Zhong, W L; Zhou, L; Zhou, Y Z; Zhou, Z Y; Zhuang, H L; Zou, J H

    2012-01-01

    The Daya Bay Reactor Neutrino Experiment is designed to determine precisely the neutrino mixing angle $\\theta_{13}$ with a sensitivity better than 0.01 in the parameter sin$^22\\theta_{13}$ at the 90% confidence level. To achieve this goal, the collaboration will build eight functionally identical antineutrino detectors. The first two detectors have been constructed, installed and commissioned in Experimental Hall 1, with steady data-taking beginning September 23, 2011. A comparison of the data collected over the subsequent three months indicates that the detectors are functionally identical, and that detector-related systematic uncertainties exceed requirements.

  17. Neutron \\beta-decay as the origin of IceCube's PeV (anti)neutrinos

    CERN Document Server

    Anchordoqui, Luis A

    2014-01-01

    Motivated by the indications of a possible deficit of muon tracks in the first three-year equivalent dataset of IceCube we investigate the possibility that the astrophysical (anti)neutrino flux (in the PeV energy range) could originate from \\beta-decay of relativistic neutrons. We show that to accommodate IceCube observations it is necessary that only \\sim 10% of the emitted cosmic rays in the energy decade 10^{8.5} \\alt E_{CR}/GeV \\alt 10^{9.5}$, yielding antineutrinos on Earth (10^{5.5} \\alt E_{\\bar \

  18. Light collection and pulse-shape discrimination in elongated scintillator cells for the PROSPECT reactor antineutrino experiment

    International Nuclear Information System (INIS)

    A meter-long, 23-liter EJ-309 liquid scintillator detector has been constructed to study the light collection and pulse-shape discrimination performance of elongated scintillator cells for the PROSPECT reactor antineutrino experiment. The magnitude and uniformity of light collection and neutron-gamma discrimination power in the energy range of antineutrino inverse beta decay products have been studied using gamma and spontaneous fission calibration sources deployed along the cell axis. We also study neutron-gamma discrimination and light collection abilities for differing PMT and reflector configurations. Key design features for optimizing MeV-scale response and background rejection capabilities are identified

  19. Light Collection and Pulse-Shape Discrimination in Elongated Scintillator Cells for the PROSPECT Reactor Antineutrino Experiment

    CERN Document Server

    Ashenfelter, J; Band, H R; Barclay, G; Bass, C D; Berish, D; Bowden, N S; Bowes, A; Brodsky, J P; Bryan, C D; Cherwinka, J J; Chu, R; Classen, T; Commeford, K; Davee, D; Dean, D; Deichert, G; Diwan, M V; Dolinski, M J; Dolph, J; Dwyer, D A; Gaison, J K; Galindo-Uribarri, A; Gilje, K; Glenn, A; Goddard, B W; Green, M; Han, K; Hans, S; Heeger, K M; Heffron, B; Jaffe, D E; Langford, T J; Littlejohn, B R; Caicedo, D A Martinez; McKeown, R D; Mendenhall, M P; Mueller, P; Mumm, H P; Napolitano, J; Neilson, R; Norcini, D; Pushin, D; Qian, X; Romero, E; Rosero, R; Saldana, L; Seilhan, B S; Sharma, R; Sheets, S; Stemen, N T; Surukuchi, P T; Varner, R L; Viren, B; Wang, W; White, B; White, C; Wilhelmi, J; Williams, C; Wise, T; Yao, H; Yeh, M; Yen, Y -R; Zangakis, G; Zhang, C; Zhang, X

    2015-01-01

    A meter-long, 23-liter EJ-309 liquid scintillator detector has been constructed to study the light collection and pulse-shape discrimination performance of elongated scintillator cells for the PROSPECT reactor antineutrino experiment. The magnitude and uniformity of light collection and neutron/gamma discrimination power in the energy range of antineutrino inverse beta decay products have been studied using gamma and spontaneous fission calibration sources deployed along the cell long axis. We also study neutron-gamma discrimination and light collection abilities for differing PMT and reflector configurations. Key design features for optimizing MeV-scale response and background rejection capabilities are identified.

  20. Charged current antineutrino reactions from 12C at MiniBooNE energies

    International Nuclear Information System (INIS)

    A study of charged current induced antineutrino interactions from nuclei has been done for the intermediate energy antineutrinos and applied to 12C, relevant for ongoing experiment by MiniBooNE collaboration. The calculations have been done for the quasielastic and inelastic lepton production as well as for the incoherent and the coherent pion production processes. The calculations are done in local density approximation. In the case of the quasielastic reaction the effects of Pauli blocking, Fermi motion effects, renormalization of weak transition strengths in nuclear medium and the Coulomb distortion of the outgoing lepton have been taken into account. For the inelastic processes the calculations have been done in the Δ dominance model and take into account the effect of Pauli blocking, Fermi motion of the nucleon, and renormalization of Δ properties in a nuclear medium. The effect of final state interactions of pions is also taken into account. The numerical results for the total cross sections for the charged current quasielastic scattering and incoherent pion production processes are compared with earlier experimental results available in freon and freon-propane. It is found that nuclear medium effects give strong reduction in the cross sections leading to satisfactory agreement with the available data

  1. Model-independent determination of the axial mass parameter in quasielastic antineutrino-nucleon scattering

    CERN Document Server

    Bhattacharya, Bhubanjyoti; Tropiano, Anthony J

    2015-01-01

    Understanding the charged current quasielestic (CCQE) neutrino-nucleus interaction is important for precision studies of neutrino oscillations. The theoretical description of the interaction depends on the combination of a nuclear model with the knowledge of form factors. While the former has received considerable attention, the latter, in particular the axial form factor, is implemented using the historical dipole model. Instead, we use a model-independent approach, presented in a previous study, to analyze the muon antineutrino CCQE mineral oil data published by the MiniBooNE collaboration. We combine the cross section for scattering of antineutrinos off protons in carbon and hydrogen, using the same axial form factor for both. The extracted value of the axial mass parameter $m_A = 0.84^{+0.12}_{-0.04} \\pm {0.11} \\, {\\rm GeV}$ is in very good agreement with the model-independent value extracted from MiniBooNE's neutrino data. Going beyond a one-parameter description of the axial form factor, we extract valu...

  2. Simulation results for light propagation in the central detector for the Angra anti-neutrinos experiment

    International Nuclear Information System (INIS)

    Full text: An antineutrino detector to be installed in the surrounding area of the Angra II nuclear reactor in Angra dos Reis is currently under development. The related experiment is intended to create a new tool capable of measuring the antineutrino flux coming from the reactor, making use of detection system placed near the reactor dome, and correlate it to the nuclear fuel fission and burn-up. The proposed detector is a box- shaped volume filled with water doped with 0.2% Gadolinium. The photons generated by the passage of particles are collected by 40 photomultiplier tubes (PMT). Aiming to evaluate the importance of reflecting inner surfaces and to provide directives concerning the best positioning of the PMTs inside the detector, a simulation of light propagation in its active volume has been done. Photons are supposed to be point-like entities traveling in straight lines. In the simulation, we investigate the overall photon counting efficiency by analyzing the number of reflections and the length travelled by the photons before being collected or absorbed, as well as the distribution of these photons in different configurations of the PMTs. Different light reflecting structures around the PMTs are also simulated, in order to find those that reduce the probability for a photon to be bounced back to the direction from which it was emitted. We show that a configuration in which the photon emission direction is preserved may be used as VETO for cosmic events. (author)

  3. New antineutrino energy spectra predictions from the summation of beta decay branches of the fission products

    CERN Document Server

    Fallot, M; Estienne, M; Algora, A; Bui, V M; Cucoanes, A; Elnimr, M; Giot, L; Jordan, D; Martino, J; Onillon, A; Porta, A; Pronost, G; Taín, J L; Yermia, F; Zakari-Issoufou, A -A

    2012-01-01

    In this paper, we study the impact of the inclusion of the recently measured beta decay properties of the $^{102;104;105;106;107}$Tc, $^{105}$Mo, and $^{101}$Nb nuclei in an updated calculation of the antineutrino energy spectra of the four fissible isotopes $^{235, 238}$U, and $^{239,241}$Pu. These actinides are the main contributors to the fission processes in Pressurized Water Reactors. The beta feeding probabilities of the above-mentioned Tc, Mo and Nb isotopes have been found to play a major role in the $\\gamma$ component of the decay heat of $^{239}$Pu, solving a large part of the $\\gamma$ discrepancy in the 4 to 3000\\,s range. They have been measured using the Total Absorption Technique (TAS), avoiding the Pandemonium effect. The calculations are performed using the information available nowadays in the nuclear databases, summing all the contributions of the beta decay branches of the fission products. Our results provide a new prediction of the antineutrino energy spectra of $^{235}$U, $^{239,241}$Pu ...

  4. First Observations of Separated Atmospheric Muon Neutrino and Muon Anti-Neutrino Events in the MINOS Detector

    CERN Document Server

    Adamson, P; Allison, W W M; Alner, G J; Anderson, K; Andreopoulos, C; Andrews, M; Andrews, R; Arroyo, C; Avvakumov, S; Ayres, D S; Baller, B; Barish, B; Barker, M A; Barnes, P D; Barr, G; Barrett, W L; Beall, E; Becker, B R; Belias, A; Bergfeld, T; Bernstein, R H; Bhattacharya, D; Bishai, M; Blake, A; Bocean, V; Bock, B; Bock, G J; Bogert, D; Border, P M; Bower, C; Boyd, S; Buckley-Geer, E; Byon-Wagner, A; Böhm, J; Böhnlein, D J; Cabrera, A; Chapman, J D; Chase, T R; Chernichenko, S K; Childress, S; Choudhary, B C; Cobb, J H; Cossairt, J D; Courant, H; Crane, D A; Culling, A J; Dawson, J W; De Muth, D M; De Santo, A; Dierckxsens, M; Diwan, M V; Dorman, M; Drake, G; Ducar, R; Durkin, T; Erwin, A R; Escobar, C O; Evans, J; Fackler, O D; Falk-Harris, E; Feldman, G J; Felt, N; Fields, T H; Ford, R; Frohne, M V; Gallagher, H R; Gebhard, M; Godley, A; Gogos, J; Goodman, M C; Gornushkin, Yu; Gouffon, P; Grashorn, E; Grossman, N; Grudzinski, J J; Grzelak, K; Guarino, V; Habig, A; Halsall, R; Hanson, J; Harris, D; Harris, P G; Hartnell, J; Hartouni, E P; Hatcher, R; Heller, K; Hill, N; Ho, Y; Howcroft, C; Hylen, J; Ignatenko, M A; Indurthy, D; Irwin, G M; James, C; Jenner, L; Jensen, D; Joffe-Minor, T M; Kafka, T; Kang, H J; Kasahara, S M; Kilmer, J; Kim, H; Koizumi, G; Kopp, S; Kordosky, M; Koskinen, D J; Kostin, M; Krakauer, D A; Kumaratunga, S; Ladran, A S; Lang, K; Laughton, C; Lebedev, A; Lee, R; Lee, W Y; Libkind, M A; Litchfield, P J; Litchfield, R P; Liu, J; Longley, N P; Lucas, P; Luebke, W; Madani, S; Maher, E; Makeev, V; Mann, W A; Marchionni, A; Marino, A D; Marshak, M L; Marshall, J S; McDonald, J; McGowan, A; Meier, J R; Merzon, G I; Messier, M D; Michael, D G; Milburn, R H; Miller, J L; Miller, W H; Mishra, S R; Miyagawa, P S; Moore, Cristopher; Morf, J; Morse, R; Mualem, L; Mufson, S; Murgia, S; Murtagh, M J; Musser, J; Naples, D; Nelson, C; Nelson, J K; Newman, H B; Nezrick, F A; Nichol, R J; Nicholls, T C; Ochoa-Ricoux, J P; Oliver, J; Oliver, W P; Onuchin, V A; Osiecki, T; Ospanov, R; Paley, J; Paolone, V; Para, A; Patzak, T; Pavlovich, Z; Pearce, G F; Pearson, N; Peck, C W; Perry, C; Peterson, E A; Petyt, D A; Ping, H; Piteira, R; Pla-Dalmau, A; Plunkett, R K; Price, L E; Proga, M; Pushka, D R; Rahman, D; Rameika, R A; Raufer, T M; Read, A L; Rebel, B; Reyna, D E; Rosenfeld, C; Rubin, H A; Ruddick, K; Ryabov, V A; Saakyan, R; Sanchez, M C; Saoulidou, N; Schneps, J; Schoessow, P V; Schreiner, P; Schwienhorst, R; Semenov, V K; Seun, S M; Shanahan, P; Shield, P D; Smart, W; Smirnitsky, A V; Smith, C; Smith, P N; Sousa, A; Speakman, B; Stamoulis, P; Stefanik, A; Sullivan, P; Swan, J M; Symes, P A; Tagg, N; Talaga, R L; Tetteh-Lartey, E; Thomas, J; Thompson, J; Thomson, M A; Thron, J L; Trendler, R; Trevor, J; Trostin, I; Tsarev, V A; Tzanakos, G S; Urheim, J; Vahle, P; Vakili, M; Vaziri, K; Velissaris, C; Verebryusov, V; Viren, B; Wai, L; Ward, C P; Ward, D R; Watabe, M; Webb, R C; Weber, A; Wehmann, A; West, N; White, C; White, R F; Wojcicki, S G; Wright, D M; Wu, Q K; Yan, W G; Yang, T; Yumiceva, F X; Yun, J C; Zheng, H; Zois, M; Zwaska, R

    2006-01-01

    The complete 5.4 kton MINOS far detector has been taking data since the beginning of August 2003 at a depth of 2070 meters water-equivalent in the Soudan mine, Minnesota. This paper presents the first MINOS observations of muon neutrino and muon anti-neutrino charged-current atmospheric neutrino interactions based on an exposure of 418 days. The ratio of upward to downward-going events in the data is compared to the Monte Carlo expectation in the absence of neutrino oscillations giving: R_data(up/down)/R_MC(up/down) = 0.62^{+0.19}_{-0.14} (stat.) +- 0.02 (sys.). An extended maximum likelihood analysis of the observed L/E distributions excludes the null hypothesis of no neutrino oscillations at the 98 % confidence level. Using the curvature of the observed muons in the 1.3 T MINOS magnetic field muon neutrino and muon anti-neutrino interactions are separated. The ratio of muon neutrino to muon anti-neutrino events in the data is compared to the Monte Carlo expectation assuming neutrinos and anti-neutrinos osci...

  5. Measurement of the Antineutrino Double-Differential Charged-Current Quasi-Elastic Scattering Cross Section at MINERvA

    Energy Technology Data Exchange (ETDEWEB)

    Patrick, Cheryl [Northwestern U.

    2016-01-01

    Next-generation neutrino oscillation experiments, such as DUNE and Hyper-Kamiokande, hope to measure charge-parity (CP) violation in the lepton sector. In order to do this, they must dramatically reduce their current levels of uncertainty, particularly those due to neutrino-nucleus interaction models. As CP violation is a measure of the difference between the oscillation properties of neutrinos and antineutrinos, data about how the less-studied antineutrinos interact is especially valuable. We present the MINERvA experiment's first double-differential scattering cross sections for antineutrinos on scintillator, in the few-GeV range relevant to experiments such as DUNE and NOvA. We also present total antineutrino-scintillator quasi-elastic cross sections as a function of energy, which we compare to measurements from previous experiments. As well as being useful to help reduce oscillation experiments' uncertainty, our data can also be used to study the prevalence of various cor relation and final-state interaction effects within the nucleus. We compare to models produced by different model generators, and are able to draw first conclusions about the predictions of these models.

  6. Status of Development of Antineutrino Detector for Short Baseline Experiment at the HANARO Research Reactor

    International Nuclear Information System (INIS)

    As the burnup proceeds, the neutrino energy spectrum deviates from the initial one. Also the rate of antineutrino production is correlated to the amount of specific fissile elements in the reactor core. By monitoring the antineutrinos during the fission process in the reactor core, scientists can estimate the variation of fissile material. A recent report published by the Department of Safeguards of IAEA also said that a short baseline (SBL) neutrino detector has intrinsic characteristics for monitoring status, operation power and nuclear fuel composition ratio in real time outside the containment building of the nuclear reactor with no-interference mode. Also many reactor neutrino experiments have searched for neutrino flavor oscillation by measuring the electron antineutrinos produced in a nuclear reactor. Since the KamLAND experiments in 2002 gave a precise observation, the neutrino flavor oscillation model has been accepted as an actual phenomenon. One of the interesting issues on reactor neutrino is an anomaly in that an event number of measured neutrinos shows a deficit of 6% compared with the expectation, which means that there should be an undetected sterile neutrino in addition to the known three flavors. It should be created in the flavor oscillations, and does not participate in a weak interaction. The recent high precision and high statistics data from Double Chooz, Daya Bay and RENO experiments may imply this. The research project, which is funded by National Research Foundation of Korea (NRF), started on June, 2012, is developing a short baseline neutrino detector close to the HANARO research reactor, and the technology for reactor monitoring by measuring precisely the neutrino energy spectrum. It is also developing a liquid scintillator containing metals that have large neutron capture cross section, and pulse shape discrimination methods. We will then have a more flexible technology that can detect reactor neutrinos overground. A prototype detector

  7. Status of Development of Antineutrino Detector for Short Baseline Experiment at the HANARO Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Gwangmin; Han, Boyoung; Kim, Hongjoo [KAERI, Daejeon(Korea, Republic of); and others

    2014-05-15

    As the burnup proceeds, the neutrino energy spectrum deviates from the initial one. Also the rate of antineutrino production is correlated to the amount of specific fissile elements in the reactor core. By monitoring the antineutrinos during the fission process in the reactor core, scientists can estimate the variation of fissile material. A recent report published by the Department of Safeguards of IAEA also said that a short baseline (SBL) neutrino detector has intrinsic characteristics for monitoring status, operation power and nuclear fuel composition ratio in real time outside the containment building of the nuclear reactor with no-interference mode. Also many reactor neutrino experiments have searched for neutrino flavor oscillation by measuring the electron antineutrinos produced in a nuclear reactor. Since the KamLAND experiments in 2002 gave a precise observation, the neutrino flavor oscillation model has been accepted as an actual phenomenon. One of the interesting issues on reactor neutrino is an anomaly in that an event number of measured neutrinos shows a deficit of 6% compared with the expectation, which means that there should be an undetected sterile neutrino in addition to the known three flavors. It should be created in the flavor oscillations, and does not participate in a weak interaction. The recent high precision and high statistics data from Double Chooz, Daya Bay and RENO experiments may imply this. The research project, which is funded by National Research Foundation of Korea (NRF), started on June, 2012, is developing a short baseline neutrino detector close to the HANARO research reactor, and the technology for reactor monitoring by measuring precisely the neutrino energy spectrum. It is also developing a liquid scintillator containing metals that have large neutron capture cross section, and pulse shape discrimination methods. We will then have a more flexible technology that can detect reactor neutrinos overground. A prototype detector

  8. Measurement of muon neutrino and antineutrino induced single neutral pion production cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Colin E. [Yale Univ., New Haven, CT (United States)

    2011-05-01

    Elucidating the nature of neutrino oscillation continues to be a goal in the vanguard of the efforts of physics experiment. As neutrino oscillation searches seek an increasingly elusive signal, a thorough understanding of the possible backgrounds becomes ever more important. Measurements of neutrino-nucleus interaction cross sections are key to this understanding. Searches for νμ → νe oscillation - a channel that may yield insight into the vanishingly small mixing parameter θ13, CP violation, and the neutrino mass hierarchy - are particularly susceptible to contamination from neutral current single π0 (NC 1π0) production. Unfortunately, the available data concerning NC 1π0 production are limited in scope and statistics. Without satisfactory constraints, theoretical models of NC 1π0 production yield substantially differing predictions in the critical Eν ~ 1 GeV regime. Additional investigation of this interaction can ameliorate the current deficiencies. The Mini Booster Neutrino Experiment (MiniBooNE) is a short-baseline neutrino oscillation search operating at the Fermi National Accelerator Laboratory (Fermilab). While the oscillation search is the principal charge of the MiniBooNE collaboration, the extensive data (~ 106 neutrino events) offer a rich resource with which to conduct neutrino cross section measurements. This work concerns the measurement of both neutrino and antineutrino NC 1π0 production cross sections at MiniBooNE. The size of the event samples used in the analysis exceeds that of all other similar experiments combined by an order of magnitude. We present the first measurements of the absolute NC 1π0 cross section as well as the first differential cross sections in both neutrino and antineutrino mode. Specifically, we measure single differential cross sections with respect to pion momentum and pion angle. We find the

  9. Development of A Prototype Short Baseline Detector for Antineutrinos from the HANARO Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Eunju; Kim, Jinyu; Kim, Yeongduk [KAERI, Daejeon (Korea, Republic of); and others

    2013-05-15

    The neutrons then cause more fissions, and the daughter nuclei decay emitting an antineutrino with each decay. Because neutrino can penetrate every thick matters composed of heavy concrete, lead and metals and so on, it is considered to be a promising monitoring probe for civil nuclear facilities and nuclear inventories. In fission process of the reactor core, uranium-235 produces antineutrinos in greater abundance than plutonium-239 over a certain energy range. As burnup proceeds, the neutrino energy spectrum deviates from an initial one. Recent report published by the Department of Safeguards of IAEA also said that a short baseline (SBL) neutrino detector has an intrinsic characteristics for monitoring status, operation power, nuclear fuel composition ratio in real time outside the containment building of the nuclear reactor with no-interference mode. Since KamLAND experiments in 2002 gave a precise observation, neutrino flavor oscillation model has been accepted to be an actual phenomenon. One of interesting issues on the reactor neutrino is an anomaly that number of measured neutrinos shows a deficit of 6% comparing with the expectation, which means that there should be an undetected sterile neutrino in addition to the known three flavors. It should be created in the flavor oscillations and does not participate in a weak interaction. The recent high precision and high statistics data from Double Chooz, Daya Bay and RENO experiments may imply it. This research develops a short baseline neutrino detector and the technology for reactor monitoring by measuring precisely the neutrino energy spectrum with a detector located close to the HANARO research reactor. Also it will develop a liquid scintillator containing metals which has large neutron capture cross section, and pulse shape discrimination methods, then we will have a more flexible technology which can detect reactor neutrinos at overground. Reactor antineutrino experiment is under preparation for the

  10. Consistent analysis of neutral- and charged-current (anti)neutrino scattering off carbon

    International Nuclear Information System (INIS)

    Good understanding of the cross sections for (anti)neutrino scattering off nuclear targets in the few-GeV energy region is a prerequisite for the correct interpretation of results of ongoing and planned oscillation experiments. To clarify a possible source of disagreement between recent measurements of the cross sections on carbon, we analyze the available data within an approach based on the realistic spectral function of carbon, treating neutral-current elastic (NCE) and charged-current quasielastic (CCQE) processes on equal footing. We show that the axial mass from the shape analysis of the MiniBooNE data is in good agreement with the results reported by the BNL E734 and NOMAD Collaborations. However, the combined analysis of the NCE and CCQE data does not seem to support the contribution of multinucleon final states being large enough to explain the normalization of the MiniBooNE-reported cross sections

  11. Terrestrial matter effects on reactor antineutrino oscillations at JUNO or RENO-50: how small is small?

    CERN Document Server

    Li, Yu-Feng; Xing, Zhi-zhong

    2016-01-01

    We have carefully examined, in both analytical and numerical ways, how small the terrestrial matter effects can be in a given medium-baseline reactor antineutrino oscillation experiment like JUNO or RENO-50. Taking the ongoing JUNO experiment for example, we show that the inclusion of terrestrial matter effects may reduce the sensitivity of the neutrino mass ordering measurement by \\Delta \\chi^2_{\\rm MO} \\simeq 0.6, and a neglect of such effects may shift the best-fit values of the flavor mixing angle \\theta_{12} and the neutrino mass-squared difference \\Delta_{21} by about 1\\sigma to 2\\sigma in the future data analysis. In addition, a preliminary estimate indicates that a 2\\sigma sensitivity of establishing the terrestrial matter effects can be achieved for about 10 years of data taking at JUNO with the help of a proper near detector implementation.

  12. Nuclear disintegration modes research with missing antineutrino in the Frejus detector

    International Nuclear Information System (INIS)

    The Frejus detector is a 900 tons fine grained calorimeter built in order to look for nucleon decay. It has reached a fiducial sensitivity of 1.3 kt. year after four years of data taking. In this thesis the decay modes with a missing anti-neutrino and one meson are studied. The analyses of all the meson decay channels are described, in particular those where the final state involves only photons or a muon due to K+ decay. The topological and kinematical cuts are different for all the channels; the detection efficiency computed by Monte -Carlo simulation ranges from 10% to 16%. The background is due to atmospheric neutrino interactions in the detector, and is estimated from a simulation. Data are consistent with the calculated background, which is smaller or close to one event per decay channel. Lower nucleon lifetime limits are obtained, which range from 0.9 1031 to 2.9 1031 years

  13. Anharmonicity of internal atomic oscillation and effective antineutrino mass evaluation from gaseous molecular tritium \\beta -decay

    CERN Document Server

    Lokhov, Alexey V

    2016-01-01

    Data analysis of the next generation effective antineutrino mass measurement experiment KATRIN requires reliable knowledge of systematic corrections. In particular, the width of the daughter molecular ion excitation spectrum rovibrational band should be known with a better then 1% precision. Very precise ab initio quantum calculations exist, and we compare them with the well known tritium molecule parameters within the framework of a phenomenological model. The rovibrational band width with accuracy of a few percent is interpreted as a result of the zero-point atomic oscillation in the harmonic potential. The Morse interatomic potential is used to investigate the impact of anharmonic atomic oscillations. The calculated corrections cannot account for the difference between the ab initio quantum calculations and the phenomenological model.

  14. Neutrino Spin-Flavor Conversions and Electron Antineutrino emission from the Sun with Random Magnetic Field

    CERN Document Server

    Semikoz, V B; Popov, V Yu; Rez, A I; Sokoloff, D D

    2000-01-01

    The magnetic field in the solar convective zone has a random small-scale component with the r.m.s. value substancially exceeding the strength of a regular large-scale field. For two Majorana neutrino flavors and two helicities in the presence of a neutrino transition magnetic moment and nonzero neutrino mixing we analize the displacement of the allowed (Delta m^2 - sin^2 2theta)-parameter region reconciled for all Underground experiments with solar neutrinos in dependence on the r.m.s. magnetic field value b. In contrary with the RSFP scenario with a regular large-scale magnetic field, we find an effective production of electron antineutrinos in the Sun even for small neutrino mixing through the cascade conversions like nu_eL -> \\bar{nu}_muR -> forbidden while opening LOW MSW as the allowed one from the non-observation of 100 kG and correlation lengths shorter than L_0 < 1000 km.

  15. SEARCH FOR EXTRATERRESTRIAL ANTINEUTRINO SOURCES WITH THE KamLAND DETECTOR

    International Nuclear Information System (INIS)

    We present the results of a search for extraterrestrial electron antineutrinos (ν-bare's) in the energy range 8.3 MeV ν-bare 8B solar νe's converting into ν-bare's at 5.3 × 10–5 (90% CL), if we assume an undistorted ν-bare shape. This limit corresponds to a solar ν-bare flux of 93 cm–2 s–1 or an event rate of 1.6 events (kton – year)–1 above the energy threshold (Eν-bare>=8.3 MeV). The present data also allows us to set more stringent limits on the diffuse supernova neutrino flux and on the annihilation rates for light dark matter particles.

  16. Four-neutrino analysis of 1.5km-baseline reactor antineutrino oscillations

    CERN Document Server

    Kang, Sin Kyu; Ko, Young-Ju; Siyeon, Kim

    2014-01-01

    The masses of sterile neutrinos are not yet known, and depending on the orders of magnitudes, their existence may explain reactor anomalies or the spectral shape of reactor neutrino events at 1.5km-baseline detector. Here, we present four-neutrino analysis of the results announced by RENO and Daya Bay, which performed the definitive measurements of $\\theta_{13}$ based on the disappearance of reactor antineutrinos at km-order baselines. Our results using 3+1 scheme include the exclusion curve of $\\Delta m^2_{41}$ vs. $\\theta_{14}$ and the adjustment of $\\theta_{13}$ due to correlation with $\\theta_{14}$. The value of $\\theta_{13}$ obtained by RENO and Daya Bay with a three-neutrino oscillation analysis is included in the $1\\sigma$ interval of $\\theta_{13}$ allowed by our four-neutrino analysis.

  17. aCORN: An experiment to measure the electron-antineutrino correlation in neutron decay

    International Nuclear Information System (INIS)

    The aCORN experiment is designed to make a precision (<1%) measurement of the electron-antineutrino angular correlation (a-coefficient) in neutron beta decay. It uses a new method proposed in 1996 by Yerozolimsky and Mostovoy. Electrons and recoil protons from neutron decay in a cold beam are detected in coincidence. The momenta of the particles are selected so that the protons form two kinematically distinct time-of-flight groups as a function of electron energy. The count rate asymmetry in these two groups is proportional to the a-coefficient. Precision spectroscopy of the protons is not required. The apparatus is currently under construction. It will be integrated and tested at the Indiana University Cyclotron Facility (IUCF) and then moved to the NIST Center for Neutron Research for the initial physics run.

  18. Neutrino mass bound in the standard scenario for supernova electronic antineutrino emission

    CERN Document Server

    Pagliaroli, Giulia; Vissani, Francesco

    2010-01-01

    Based on recent improvements of the supernova electron antineutrino emission model, we update the limit on neutrino mass from the SN1987A data collected by Kamiokande-II, IMB and Baksan. We derive the limit of 5.8 eV at 95 % CL, that we show to be remarkably insensitive to the astrophysical uncertainties. Also we evaluate the ultimate mass sensitivity of this method for a detector like Super-Kamiokande. We find that the bound lies in the sub-eV region, 0.8 eV at 95 % CL being a typical outcome, competitive with the values that are presently probed in laboratory. However, this bound is subject to strong statistical fluctuations, correlated to the characteristics of the first few events detected. We briefly comment on the prospects offered by future detectors.

  19. Consistent analysis of neutral- and charged-current (anti)neutrino scattering off carbon

    CERN Document Server

    Ankowski, Artur M

    2013-01-01

    Good understanding of the cross sections for (anti)neutrino scattering off nuclear targets in the few-GeV energy region is a prerequisite for the correct interpretation of results of ongoing and planned oscillation experiments. To clarify a possible source of disagreement between recent measurements of the cross sections on carbon, we analyze the available data within an approach based on the realistic spectral function of carbon, treating neutral-current elastic (NCE) and charged-current quasielastic (CCQE) processes on equal footing. We show that the axial mass from the shape analysis of the MiniBooNE data is in good agreement with the results reported by the BNL E734 and NOMAD Collaborations. However, the combined analysis of the NCE and CCQE data does not seem to support the contribution of multinucleon final states being large enough to explain the normalization of the MiniBooNE-reported cross sections.

  20. Neutrino-Antineutrino Mass Splitting in the Standard Model: Neutrino Oscillation and Baryogenesis

    Science.gov (United States)

    Fujikawa, Kazuo; Tureanu, Anca

    By adding a neutrino mass term to the Standard Model, which is Lorentz and SU(2) × U(1) invariant but nonlocal to evade CPT theorem, it is shown that nonlocality within a distance scale of the Planck length, that may not be fatal to unitarity in generic effective theory, can generate the neutrino-antineutrino mass splitting of the order of observed neutrino mass differences, which is tested in oscillation experiments, and non-negligible baryon asymmetry depending on the estimate of sphaleron dynamics. The one-loop order induced electron-positron mass splitting in the Standard Model is shown to be finite and estimated at ˜ 10-20 eV, well below the experimental bound bar{K}}| < 0.44 × 10^{-18} GeV.

  1. A new anti-neutrino detection technique based on positronium tagging with plastic scintillators

    CERN Document Server

    Consolati, G; Jollet, C; Meregaglia, A; Minotti, A; Perasso, S; Tonazzo, A

    2015-01-01

    The main signature for anti-neutrino detection in reactor and geo-neutrino experiments based on scintillators is provided by the space-time coincidence of positron and neutron produced in the Inverse Beta Decay reaction. Such a signature strongly suppresses backgrounds and allows for measurements performed underground with a relatively high signal-to-background ratio. In an aboveground environment, however, the twofold coincidence technique is not sufficient to efficiently reject the high background rate induced by cosmogenic events. Enhancing the positron-neutron twofold coincidence efficiency has the potential to pave the way future aboveground detectors for reactor monitoring. We propose a new detection scheme based on a threefold coincidence, between the positron ionization, the ortho-positronium (o-Ps) decay, and the neutron capture, in a sandwich detector with alternated layers of plastic scintillator and aerogel powder. We present the results of a set of dedicated measurements on the achievable light y...

  2. Measurement of Muon Antineutrino Quasi-Elastic Scattering on a Hydrocarbon Target at E_{\

    CERN Document Server

    Fields, L; Aliaga, L; Altinok, O; Bodek, A; Boehnlein, D; Bradford, R; Brooks, W K; Budd, H; Butkevich, A; Caicedo, D A M; Castromonte, C M; Christy, M E; da Motta, H; Damiani, D S; Danko, I; Datta, M; Day, M; DeMaat, R; Devan, J; Diaz, G A; Dytman, S A; Eberly, B; Edmondson, D A; Felix, J; Fitzpatrick, T; Fiorentini, G A; Gago, A M; Gallagher, H; Gobbi, B; Gran, R; Harris, D A; Higuera, A; Howley, I J; Hurtado, K; Jerkins, M; Kafka, T; Kanter, M O; Keppel, C; Kordosky, M; Krajeski, A H; Kulagin, S A; Le, T; Leister, A G; Maggi, G; Maher, E; Manly, S; Mann, W A; Marshall, C M; McFarland, K S; McGivern, C L; McGowan, A M; Mislivec, A; Morfin, J G; Mousseau, J; Naples, D; Nelson, J K; Niculescu, G; Niculescu, I; Ochoa, N; O'Connor, C D; Osta, J; Palomino, J L; Paolone, V; Park, J; Patrick, C E; Perdue, G N; Pena, C; Rakotondravohitra, L; Ransome, R D; Ray, H; Ren, L; Rodrigues, P A; Sassin, K E; Schellman, H; Schmitz, D W; Schneider, R M; Schulte, E C; Sedita, P; Simon, C; Snider, F D; Snyder, M C; Sobczyk, J T; Salinas, C J Solano; Tagg, N; Tan, W; Tice, B G; Tzanakos, G; Velasquez, J P; Walding, J; Walton, T; Wolcott, J; Wolthuis, B A; Zavala, G; Zhang, D; Ziemer, B P

    2013-01-01

    We have isolated muon anti-neutrino charged-current quasi-elastic interactions occurring in the segmented scintillator tracking region of the MINERvA detector running in the NuMI neutrino beam at Fermilab. We measure the flux-averaged differential cross-section, d{\\sigma}/dQ^2, and compare to several theoretical models of quasi-elastic scattering. Good agreement is obtained with a model where the nucleon axial mass, M_A, is set to 0.99 GeV/c^2 but the nucleon vector form factors are modified to account for the observed enhancement, relative to the free nucleon case, of the cross-section for the exchange of transversely polarized photons in electron-nucleus scattering. Our data at higher Q^2 favor this interpretation over an alternative in which the axial mass is increased.

  3. Study on the 6He β-decay with account for second-class currents and antineutrino mass

    International Nuclear Information System (INIS)

    The effects of the rest mass of electron antineutrino are studied taking into account the induced tensor form factor Ft of second kind current according to the Weinberg classification in the course of 6He nucleus β-decay. The contribution of mν and Ft into the electron-antineutrino angular correlation coefficient Aeν and degree of longitudinal polarization of decay electrons. It is shown that in the case of mν difference from zero independently of second kind current account Aeν coefficient both at the begining and end of the β spectrum asymptotically tends to zero. It is noted that qualitatively new experiments on measurement of the e-ν correlation for pure Gamov-Teller transitions with the 1% accuracy being planned for the nearest future will permit to considerably improve the available estimations by the Ft form factor value

  4. Total neutrino and antineutrino charged current cross section measurements in 100, 160, and 200 GeV narrow band beams

    International Nuclear Information System (INIS)

    Neutrino and antineutrino total charged current cross sections on iron were measured in the 100, 160, and 200 GeV narrow band beams at the CERN SPS in the energy range 10 to 200 GeV. Assuming σ/E to be constant, the values corrected for non-isoscalarity are σν/E=(0.686 ±0.019)x10-38 cm2/(GeV . nucleon) and σν/E=(0.339±0.010)x10-38 cm2/(GeV . nucleon). Between 50 and 150 GeV no energy dependence of σ/E was observed within ±3% for neutrino and ±4% for antineutrino interactions. (orig.)

  5. Comment on Phys. Rev. Lett. 108, 191802 (2012): "Observation of Reactor Electron Antineutrino Disappearance in the RENO Experiment"

    CERN Document Server

    Lasserre, Thierry; Cribier, Michel; Collin, Antoine; Durand, Vincent; Fischer, Vincent; Gaffiot, Jonathan; Lhuillier, David; Letourneau, Alain; Vivier, Matthieu

    2012-01-01

    The RENO experiment recently reported the disappearance of reactor electron antineutrinos consistent with neutrino oscillations, with a significance of 4.9 standard deviations. The published ratio of observed to expected number of antineutrinos in the far detector is R=0.920 +-0.009(stat.) +-0.014(syst.) and corresponds to sin^2 2theta13 = 0.113 +-0.013(stat.) +-0.019(syst), using a rate-only analysis. In this letter we reanalyze the data and we find a ratio R=0.903 +-0.01(stat.), leading to sin^2 2theta13 = 0.135. Moreover we show that the sin^2 2theta13 measurement still depend of the prompt high energy bound beyond 4 MeV, contrarily to the expectation based on neutrino oscillation.

  6. Integrated readout of organic scintillator and ZnS:Ag/6LiF for segmented antineutrino detectors.

    Energy Technology Data Exchange (ETDEWEB)

    Kiff, Scott D.; Reyna, David; Monahan, James; Bowden, Nathaniel S.

    2010-11-01

    Antineutrino detection using inverse beta decay conversion has demonstrated the capability to measure nuclear reactor power and fissile material content for nuclear safeguards. Current efforts focus on aboveground deployment scenarios, for which highly efficient capture and identification of neutrons is needed to measure the anticipated antineutrino event rates in an elevated background environment. In this submission, we report on initial characterization of a new scintillation-based segmented design that uses layers of ZnS:Ag/{sup 6}LiF and an integrated readout technique to capture and identify neutrons created in the inverse beta decay reaction. Laboratory studies with multiple organic scintillator and ZnS:Ag/{sup 6}LiF configurations reliably identify {sup 6}Li neutron captures in 60 cm-long segments using pulse shape discrimination.

  7. Integrated readout of organic scintillator and ZnS:Ag/6LiF for segmented antineutrino detectors.

    Energy Technology Data Exchange (ETDEWEB)

    Kiff, Scott D.; Reyna, David; Monahan, James (Drexel University, Philadelphia, PA); Bowden, Nathaniel S. (Lawrence Livermore National Laboratory, Livermore, CA)

    2010-10-01

    Antineutrino detection using inverse beta decay conversion has demonstrated the capability to measure nuclear reactor power and fissile material content for nuclear safeguards. Current efforts focus on aboveground deployment scenarios, for which highly efficient capture and identification of neutrons is needed to measure the anticipated antineutrino event rates in an elevated background environment. In this submission, we report on initial characterization of a new scintillation-based segmented design that uses layers of ZnS:Ag/{sup 6}LiF and an integrated readout technique to capture and identify neutrons created in the inverse beta decay reaction. Laboratory studies with multiple organic scintillator and ZnS:Ag/{sup 6}LiF configurations reliably identify {sup 6}Li neutron captures in 60 cm-long segments using pulse shape discrimination.

  8. Neutron detection and identification using ZnS:Ag/{sup 6}LiF in segmented antineutrino detectors

    Energy Technology Data Exchange (ETDEWEB)

    Kiff, Scott D., E-mail: skiff@sandia.gov [Sandia National Laboratories, 7011 East Avenue, Livermore, CA 94550 (United States); Bowden, Nathaniel [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550 (United States); Lund, Jim; Reyna, David [Sandia National Laboratories, 7011 East Avenue, Livermore, CA 94550 (United States)

    2011-10-01

    Antineutrino detection using inverse beta-decay conversion has demonstrated capability to measure nuclear reactor power and fissile material content for nuclear safeguards. Current efforts focus on aboveground deployment scenarios, for which a successful background rejection strategy will be needed to measure the anticipated antineutrino event rates. In this paper, we report on initial studies to quantify the intrinsic capture efficiency and particle identification capabilities of a new scintillation-based segmented design that uses layers of ZnS:Ag/{sup 6}LiF to capture and identify neutrons created in the inverse beta-decay reaction. Laboratory efficiency measurements are consistent with MCNP5 calculations, estimating {sup 6}Li neutron conversion efficiency above 50% for practical full-scale detector configurations.

  9. Background for Terrestrial Antineutrino Investigations: Scientific Basis of Knowledge on the Composition of the Deep Interior of the Earth

    OpenAIRE

    Herndon, J. Marvin

    2004-01-01

    I present from a historical perspective a logical progression of understanding, related to the composition of the deep interior of the Earth, that comes from fundamental discoveries and from discoveries of fundamental quantitative relationships in nature. By following step by step the reasoning from that understanding, one might begin to appreciate what is not yet known that pertains to recent interest in geo-antineutrinos and also what should be investigated to further advance that understan...

  10. Film data processing system of the antineutrino experiment in the HYDRA system on the BESM-6 computer

    International Nuclear Information System (INIS)

    Described is the system for mathematical processing of the film data of an antineutrino experiment. The system is based on the HYDRA system with the use of a modular principle. Functionally the mathematical processing system is divided into three parts: primary data processing, geometrical reconstruction of events, and kinematic balance. Use of the said system makes it possible to quickly and efficiently process the film data from measuring devices

  11. A feasibility study of boron-loaded liquid scintillator for the detection of electron anti-neutrinos

    CERN Document Server

    Wang, S C; Leung, R W S; Wang, S L; Chang, C Y; Chen Chi Ping; Cheng, K C; Ho, T I; Lai, W P; Liu, H M; Mao, Z P; Shih, I C; Wong, H T; Yu, Z Q

    1999-01-01

    Boron-loaded liquid scintillator offers some potential advantages as a detector for electron anti-neutrinos. A research program was carried out with the objective of developing such scintillators. The crucial feature is the pulse shape discrimination properties following the neutron capture by sup 1 sup 0 B. Results of the R and D efforts are presented. The feasibility and the technical difficulties of carrying out a full-scale neutrino experiment based on this approach are discussed. (author)

  12. Method of fission product beta spectra measurements for predicting reactor anti-neutrino emission

    International Nuclear Information System (INIS)

    The nuclear fission process that occurs in the core of nuclear reactors results in unstable, neutron-rich fission products that subsequently beta decay and emit electron antineutrinos. These reactor neutrinos have served neutrino physics research from the initial discovery of the neutrino to today's precision measurements of neutrino mixing angles. The prediction of the absolute flux and energy spectrum of the emitted reactor neutrinos hinges upon a series of seminal papers based on measurements performed in the 1970s and 1980s. The steadily improving reactor neutrino measurement techniques and recent reconsiderations of the agreement between the predicted and observed reactor neutrino flux motivates revisiting the underlying beta spectra measurements. A method is proposed to use an accelerator proton beam delivered to an engineered target to yield a neutron field tailored to reproduce the neutron energy spectrum present in the core of an operating nuclear reactor. Foils of the primary reactor fissionable isotopes placed in this tailored neutron flux will ultimately emit beta particles from the resultant fission products. Measurement of these beta particles in a time projection chamber with a perpendicular magnetic field provides a distinctive set of systematic considerations for comparison to the original seminal beta spectra measurements. Ancillary measurements such as gamma-ray emission and post-irradiation radiochemical analysis will further constrain the absolute normalization of beta emissions per fission. The requirements for unfolding the beta spectra measured with this method into a predicted reactor neutrino spectrum are explored.

  13. A new anti-neutrino detection technique based on positronium tagging with plastic scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Consolati, G. [Department of Aerospace Science and Technology, Politecnico di Milano, via La Masa 34, 20156 Milano (Italy); Franco, D., E-mail: dfranco@in2p3.fr [APC, Univ. Paris Diderot, CNRS/IN2P3, CEA/Irfu, Obs. de Paris, Sorbonne Paris Cité, 75205 Paris (France); Jollet, C. [IPHC, Université de Strasbourg, CNRS/IN2P3, 67037 Strasbourg (France); Meregaglia, A., E-mail: amerega@in2p3.fr [IPHC, Université de Strasbourg, CNRS/IN2P3, 67037 Strasbourg (France); Minotti, A. [IPHC, Université de Strasbourg, CNRS/IN2P3, 67037 Strasbourg (France); Perasso, S.; Tonazzo, A. [APC, Univ. Paris Diderot, CNRS/IN2P3, CEA/Irfu, Obs. de Paris, Sorbonne Paris Cité, 75205 Paris (France)

    2015-09-21

    The main signature for anti-neutrino detection in reactor and geo-neutrino experiments based on scintillators is provided by the space–time coincidence of positron and neutron produced in the Inverse Beta Decay reaction. Such a signature strongly suppresses backgrounds and allows for measurements performed underground with a relatively high signal-to-background ratio. In an aboveground environment, however, the twofold coincidence technique is not sufficient to efficiently reject the high background rate induced by cosmogenic events. Enhancing the positron–neutron twofold coincidence efficiency may pave the way to future aboveground detectors for reactor monitoring. We propose a new detection scheme based on a threefold coincidence, among the positron ionization, the ortho-positronium (o-Ps) decay, and the neutron capture, in a sandwich detector with alternated layers of plastic scintillator and aerogel powder. We present the results of a set of dedicated measurements on the achievable light yield and on the o-Ps formation and lifetime. The efficiencies for signal detection and background rejection of a preliminary detector design are also discussed.

  14. Nonstandard interaction effects on neutrino parameters at medium-baseline reactor antineutrino experiments

    International Nuclear Information System (INIS)

    Precision measurements of leptonic mixing parameters and the determination of the neutrino mass hierarchy are the primary goals of the forthcoming medium-baseline reactor antineutrino experiments, such as JUNO and RENO-50. In this work, we investigate the impact of nonstandard neutrino interactions (NSIs) on the measurements of {sin2θ12,Δm212} and {sin2θ13,Δm312}, and on the sensitivity to the neutrino mass hierarchy, at the medium-baseline reactor experiments by assuming a typical experimental setup. It turns out that the true mixing parameter sin2θ12 can be excluded at a more than 3σ level if the NSI parameter εeμ or εeτ is as large as 2% in the most optimistic case. However, the discovery reach of NSI effects has been found to be small, and depends crucially on the CP-violating phases. Finally, we show that NSI effects could enhance or reduce the discrimination power of the JUNO and RENO-50 experiments between the normal and inverted neutrino mass hierarchies

  15. A new anti-neutrino detection technique based on positronium tagging with plastic scintillators

    International Nuclear Information System (INIS)

    The main signature for anti-neutrino detection in reactor and geo-neutrino experiments based on scintillators is provided by the space–time coincidence of positron and neutron produced in the Inverse Beta Decay reaction. Such a signature strongly suppresses backgrounds and allows for measurements performed underground with a relatively high signal-to-background ratio. In an aboveground environment, however, the twofold coincidence technique is not sufficient to efficiently reject the high background rate induced by cosmogenic events. Enhancing the positron–neutron twofold coincidence efficiency may pave the way to future aboveground detectors for reactor monitoring. We propose a new detection scheme based on a threefold coincidence, among the positron ionization, the ortho-positronium (o-Ps) decay, and the neutron capture, in a sandwich detector with alternated layers of plastic scintillator and aerogel powder. We present the results of a set of dedicated measurements on the achievable light yield and on the o-Ps formation and lifetime. The efficiencies for signal detection and background rejection of a preliminary detector design are also discussed

  16. Study of neutral current reactions with production of a pion induced by muon antineutrinos

    International Nuclear Information System (INIS)

    In this work we have studied the 4 production reactions of a pion induced by muon anti-neutrino collisions with nucleons: anti-νμp → anti-νμpπ0 or anti-νμnπ+ and anti-νμn → anti-νμnπ0 or anti-νμpπ-. We have processed experimental data from the Gargamelle cloud chamber to assess the pion production cross-sections. Our results are consistent with the theoretical predictions of the Adler model and of the Fogli and Nardulli model within the framework of the Weinberg and Salam unified theory. As for the isospin structure of the weak hadronic neutral current, the iso-vectorial component is highlighted in the invariant mass spectra in the channels pπ0 and pπ-. Our results show that the isospin structure is not purely isoscalar or purely iso-vectorial but rather a mix of I = 0 and I = 1. We confirm that the sign of the product of the 2 coupling constants uL*dL is negative. (A.C.)

  17. Contribution of Recently Measured Nuclear Data to Reactor Antineutrino Energy Spectra Predictions

    International Nuclear Information System (INIS)

    The aim of this work is to study the impact of the inclusion of the recently measured β decay properties of the 102,104,105,106,107Tc, 105Mo, and 101Nb nuclei in the calculation of the antineutrino (anti-ν) energy spectra arising after the fissions of the four main fissile isotopes 235,238U, and 239,241Pu in PWRs. These β feeding probabilities, measured using the Total Absorption Technique (TAS) at the JYFL facility of Jyväskylä, have been found to play a major role in the γ component of the decay heat for 239Pu in the 4-3000 s range. Following the fission product summation method, the calculation was performed using the MCNP Utility Reactor Evolution code (MURE) coupled to the experimental spectra built from β decay properties of the fission products taken from evaluated databases. These latest TAS data are found to have a significant effect on the Pu isotope energy spectra and on the spectrum of 238U showing the importance of their measurement for a better assessment of the reactor anti-ν energy spectrum, as well as importance for fundamental neutrino physics experiments and neutrino applied physics

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

    International Nuclear Information System (INIS)

    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 νe and ν-bare fluxes and on the number of events for νe + C12, νe + O16, νe + Ar40 and ν-bare + 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)

  19. Method of fission product beta spectra measurements for predicting reactor anti-neutrino emission

    International Nuclear Information System (INIS)

    The nuclear fission process that occurs in the core of nuclear reactors results in unstable, neutron-rich fission products that subsequently beta decay and emit electron antineutrinos. These reactor neutrinos have served neutrino physics research from the initial discovery of the neutrino to today's precision measurements of neutrino mixing angles. The prediction of the absolute flux and energy spectrum of the emitted reactor neutrinos hinges upon a series of seminal papers based on measurements performed in the 1970s and 1980s. The steadily improving reactor neutrino measurement techniques and recent reconsiderations of the agreement between the predicted and observed reactor neutrino flux motivates revisiting the underlying beta spectra measurements. A method is proposed to use an accelerator proton beam delivered to an engineered target to yield a neutron field tailored to reproduce the neutron energy spectrum present in the core of an operating nuclear reactor. Foils of the primary reactor fissionable isotopes placed in this tailored neutron flux will ultimately emit beta particles from the resultant fission products. Measurement of these beta particles in a time projection chamber with a perpendicular magnetic field provides a distinctive set of systematic considerations for comparison to the original seminal beta spectra measurements. Ancillary measurements such as gamma-ray emission and post-irradiation radiochemical analysis will further constrain the absolute normalization of beta emissions per fission. The requirements for unfolding the beta spectra measured with this method into a predicted reactor neutrino spectrum are explored

  20. Geneva University: Observation of electron-antineutrino disappearance at Daya Bay

    CERN Document Server

    Université de Genève

    2012-01-01

    GENEVA UNIVERSITY École de physique Département de physique nucléaire et corspusculaire 24, quai Ernest-Ansermet 1211 Genève 4 Tél.: (022) 379 62 73 Fax: (022) 379 69 92 Monday 19 March 2012 COLLOQUE DE PHYSIQUE 5 p.m. - École de Physique, Auditoire Stueckelberg Observation of electron-antineutrino disappearance at Daya Bay  Professor Yifang Wang Institute of High Energy Physics of the Chinese Academy of Sciences Beijing The Daya Bay Reactor Neutrino Experiment, a multinational collaboration operating in the south of China, today reported the first results of its search for the last, most elusive piece of a long-standing puzzle: how is it that neutrinos can appear to vanish as they travel? The surprising answer opens a gateway to a new understanding of fundamental physics and may eventually solve the riddle of why there is far more ordinary matter than antimatter in the Universe today....

  1. Supernova neutrinos and antineutrinos: ternary luminosity diagram and spectral split patterns

    International Nuclear Information System (INIS)

    In core-collapse supernovae, the νe and ν-bar e species may experience collective flavor swaps to non-electron species νx, within energy intervals limited by relatively sharp boundaries (''splits''). These phenomena appear to depend sensitively upon the initial energy spectra and luminosities. We investigate the effect of generic variations of the fractional luminosities (le, lē, lx) with respect to the usual ''energy equipartition'' case (1/6, 1/6, 1/6), within an early-time supernova scenario with fixed thermal spectra and total luminosity. We represent the constraint le+lē+4lx = 1 in a ternary diagram, which is explored via numerical experiments (in single-angle approximation) over an evenly-spaced grid of points. In inverted hierarchy, single splits arise in most cases, but an abrupt transition to double splits is observed for a few points surrounding the equipartition one. In normal hierarchy, collective effects turn out to be unobservable at all grid points but one, where single splits occur. Admissible deviations from equipartition may thus induce dramatic changes in the shape of supernova (anti)neutrino spectra. The observed patterns are interpreted in terms of initial flavor polarization vectors (defining boundaries for the single/double split transitions), lepton number conservation, and minimization of potential energy

  2. Nonstandard interaction effects on neutrino parameters at medium-baseline reactor antineutrino experiments

    CERN Document Server

    Ohlsson, Tommy; Zhou, Shun

    2014-01-01

    Precision measurements of leptonic mixing parameters and the determination of the neutrino mass hierarchy are the primary goals of the forthcoming medium-baseline reactor antineutrino experiments, such as JUNO and RENO-50. In this work, we investigate the impact of nonstandard neutrino interactions (NSIs) on the measurements of {sin^2 theta_{12}, Delta m^2_{21}} and {sin^2 theta_{13}, Delta m^2_{31}}, and on the sensitivity to the neutrino mass hierarchy, at the medium-baseline reactor experiments by assuming a typical experimental setup. It turns out that the true mixing parameter sin^2 theta_{12} can be excluded at a more than 3 sigma level if the NSI parameter varepsilon_{e mu} or varepsilon_{e tau} is as large as 2% in the most optimistic case. However, the discovery reach of NSI effects has been found to be small, and depends crucially on the CP-violating phases. Finally, we show that NSI effects could enhance or reduce the discrimination power of the JUNO and RENO-50 experiments between the normal and i...

  3. Observation of Energy and Baseline Dependent Reactor Antineutrino Disappearance in the RENO Experiment

    Science.gov (United States)

    Choi, J. H.; Choi, W. Q.; Choi, Y.; Jang, H. I.; Jang, J. S.; Jeon, E. J.; Joo, K. K.; Kim, B. R.; Kim, H. S.; Kim, J. Y.; Kim, S. B.; Kim, S. Y.; Kim, W.; Kim, Y. D.; Ko, Y.; Lee, D. H.; Lim, I. T.; Pac, M. Y.; Park, I. G.; Park, J. S.; Park, R. G.; Seo, H.; Seo, S. H.; Seon, Y. G.; Shin, C. D.; Siyeon, K.; Yang, J. H.; Yeo, I. S.; Yu, I.; RENO Collaboration

    2016-05-01

    The RENO experiment has analyzed about 500 live days of data to observe an energy dependent disappearance of reactor ν¯e by comparing their prompt signal spectra measured in two identical near and far detectors. In the period between August of 2011 and January of 2013, the far (near) detector observed 31 541 (290 775) electron antineutrino candidate events with a background fraction of 4.9% (2.8%). The measured prompt spectra show an excess of reactor ν¯e around 5 MeV relative to the prediction from a most commonly used model. A clear energy and baseline dependent disappearance of reactor ν¯e is observed in the deficit of the observed number of ν¯e. Based on the measured far-to-near ratio of prompt spectra, we obtain sin22 θ13=0.082 ±0.009 (stat)±0.006 (syst) and |Δ mee 2|=[2.6 2-0.23+0.21(stat)-0.13+0.12(syst)]×10-3 eV2 .

  4. Earth Radioactivity Measurements with a Deep Ocean Anti-neutrino Observatory

    CERN Document Server

    Dye, S T; Learned, J G; Maricic, J; Matsuno, S; Pakvasa, S; Varner, G; Wilcox, M

    2006-01-01

    We consider the detector size, location, depth, backgrounds, and radio-purity required of a mid-Pacific deep-ocean instrument to accomplish the twin goals of making a definitive measurement of the electron anti-neutrino flux due to uranium and thorium decays from Earth's mantle and core, and of testing the hypothesis for a natural nuclear reactor at the core of Earth. We take the experience with the KamLAND detector in Japan as our baseline for sensitivity and background estimates. We conclude that an instrument adequate to accomplish these tasks should have an exposure of at least 10 kilotonne-years (kT-y), should be placed at least at 4 km depth, may be located close to the Hawaiian Islands (no significant background from them), and should aim for KamLAND radio-purity levels, except for radon where it should be improved by a factor of at least 40. With an exposure of 10 kT-y we should achieve a 24% measurement of the U/Th content of the mantle plus core. Exposure at multiple ocean locations for testing late...

  5. Method of fission product beta spectra measurements for predicting reactor anti-neutrino emission

    Energy Technology Data Exchange (ETDEWEB)

    Asner, David M.; Burns, Kimberly A.; Campbell, Luke W.; Greenfield, Bryce A.; Kos, Marek S.; Orrell, John L.; Schram, Malachi; VanDevender, Brent A.; Wood, Lynn S.; Wootan, David W.

    2015-03-01

    The nuclear fission process that occurs in the core of nuclear reactors results in unstable, neutron-rich fission products that subsequently beta decay and emit electron antineutrinos. These reactor neutrinos have served neutrino physics research from the initial discovery of the neutrino to today's precision measurements of neutrino mixing angles. The prediction of the absolute flux and energy spectrum of the emitted reactor neutrinos hinges upon a series of seminal papers based on measurements performed in the 1970s and 1980s. The steadily improving reactor neutrino measurement techniques and recent reconsiderations of the agreement between the predicted and observed reactor neutrino flux motivates revisiting the underlying beta spectra measurements. A method is proposed to use an accelerator proton beam delivered to an engineered target to yield a neutron field tailored to reproduce the neutron energy spectrum present in the core of an operating nuclear reactor. Foils of the primary reactor fissionable isotopes placed in this tailored neutron flux will ultimately emit beta particles from the resultant fission products. Measurement of these beta particles in a time projection chamber with a perpendicular magnetic field provides a distinctive set of systematic considerations for comparison to the original seminal beta spectra measurements. Ancillary measurements such as gamma-ray emission and post-irradiation radiochemical analysis will further constrain the absolute normalization of beta emissions per fission. The requirements for unfolding the beta spectra measured with this method into a predicted reactor neutrino spectrum are explored.

  6. Data processing and storage in the Daya Bay Reactor Antineutrino Experiment

    CERN Document Server

    He, Miao

    2015-01-01

    The Daya Bay Reactor Antineutrino Experiment reported the first observation of the non-zero neutrino mixing angle $\\theta_{13}$ using the first 55 days of data. It has also provided the most precise measurement of $\\theta_{13}$ with the extended data to 621 days. Daya Bay will keep running for another 3 years or so. There is about 100 TB raw data produced per year, as well as several copies of reconstruction data with similar volume to the raw data for each copy. The raw data is transferred to Daya Bay onsite and two offsite clusters: IHEP in Beijing and LBNL in California, with a short latency. There is quasi-real-time data processing at both onsite and offsite clusters, for the purpose of data quality monitoring, detector calibration and preliminary data analyses. The physics data production took place a couple of times per year according to the physics analysis plan. This paper will introduce the data movement and storage, data processing and monitoring, and the automation of the calibration.

  7. Measurement of Muon Antineutrino Oscillations with an Accelerator-Produced Off-Axis Beam.

    Science.gov (United States)

    Abe, K; Andreopoulos, C; Antonova, M; Aoki, S; Ariga, A; Assylbekov, S; Autiero, D; Barbi, M; Barker, G J; Barr, G; Bartet-Friburg, P; Batkiewicz, M; Bay, F; Berardi, V; Berkman, S; Bhadra, S; Blondel, A; Bolognesi, S; Bordoni, S; Boyd, S B; Brailsford, D; Bravar, A; Bronner, C; Buizza Avanzini, M; Calland, R G; Cao, S; Caravaca Rodríguez, J; Cartwright, S L; Castillo, R; Catanesi, M G; Cervera, A; Cherdack, D; Chikuma, N; Christodoulou, G; Clifton, A; Coleman, J; Collazuol, G; Cremonesi, L; Dabrowska, A; De Rosa, G; Dealtry, T; Denner, P F; Dennis, S R; Densham, C; Dewhurst, D; Di Lodovico, F; Di Luise, S; Dolan, S; Drapier, O; Duffy, K E; Dumarchez, J; Dytman, S; Dziewiecki, M; Emery-Schrenk, S; Ereditato, A; Feusels, T; Finch, A J; Fiorentini, G A; Friend, M; Fujii, Y; Fukuda, D; Fukuda, Y; Furmanski, A P; Galymov, V; Garcia, A; Giffin, S G; Giganti, C; Gizzarelli, F; Gonin, M; Grant, N; Hadley, D R; Haegel, L; Haigh, M D; Hamilton, P; Hansen, D; Hara, T; Hartz, M; Hasegawa, T; Hastings, N C; Hayashino, T; Hayato, Y; Helmer, R L; Hierholzer, M; Hillairet, A; Himmel, A; Hiraki, T; Hirota, S; Hogan, M; Holeczek, J; Horikawa, S; Hosomi, F; Huang, K; Ichikawa, A K; Ieki, K; Ikeda, M; Imber, J; Insler, J; Intonti, R A; Irvine, T J; Ishida, T; Ishii, T; Iwai, E; Iwamoto, K; Izmaylov, A; Jacob, A; Jamieson, B; Jiang, M; Johnson, S; Jo, J H; Jonsson, P; Jung, C K; Kabirnezhad, M; Kaboth, A C; Kajita, T; Kakuno, H; Kameda, J; Karlen, D; Karpikov, I; Katori, T; Kearns, E; Khabibullin, M; Khotjantsev, A; Kielczewska, D; Kikawa, T; Kim, H; Kim, J; King, S; Kisiel, J; Knight, A; Knox, A; Kobayashi, T; Koch, L; Koga, T; Konaka, A; Kondo, K; Kopylov, A; Kormos, L L; Korzenev, A; Koshio, Y; Kropp, W; Kudenko, Y; Kurjata, R; Kutter, T; Lagoda, J; Lamont, I; Larkin, E; Laveder, M; Lawe, M; Lazos, M; Lindner, T; Liptak, Z J; Litchfield, R P; Li, X; Longhin, A; Lopez, J P; Ludovici, L; Lu, X; Magaletti, L; Mahn, K; Malek, M; Manly, S; Marino, A D; Marteau, J; Martin, J F; Martins, P; Martynenko, S; Maruyama, T; Matveev, V; Mavrokoridis, K; Ma, W Y; Mazzucato, E; McCarthy, M; McCauley, N; McFarland, K S; McGrew, C; Mefodiev, A; Mezzetto, M; Mijakowski, P; Minamino, A; Mineev, O; Mine, S; Missert, A; Miura, M; Moriyama, S; Mueller, Th A; Murphy, S; Myslik, J; Nakadaira, T; Nakahata, M; Nakamura, K G; Nakamura, K; Nakamura, K D; Nakayama, S; Nakaya, T; Nakayoshi, K; Nantais, C; Nielsen, C; Nirkko, M; Nishikawa, K; Nishimura, Y; Nowak, J; O'Keeffe, H M; Ohta, R; Okumura, K; Okusawa, T; Oryszczak, W; Oser, S M; Ovsyannikova, T; Owen, R A; Oyama, Y; Palladino, V; Palomino, J L; Paolone, V; Patel, N D; Pavin, M; Payne, D; Perkin, J D; Petrov, Y; Pickard, L; Pickering, L; Pinzon Guerra, E S; Pistillo, C; Popov, B; Posiadala-Zezula, M; Poutissou, J-M; Poutissou, R; Przewlocki, P; Quilain, B; Radicioni, E; Ratoff, P N; Ravonel, M; Rayner, M A M; Redij, A; Reinherz-Aronis, E; Riccio, C; Rojas, P; Rondio, E; Roth, S; Rubbia, A; Rychter, A; Sacco, R; Sakashita, K; Sánchez, F; Sato, F; Scantamburlo, E; Scholberg, K; Schoppmann, S; Schwehr, J; Scott, M; Seiya, Y; Sekiguchi, T; Sekiya, H; Sgalaberna, D; Shah, R; Shaikhiev, A; Shaker, F; Shaw, D; Shiozawa, M; Shirahige, T; Short, S; Smy, M; Sobczyk, J T; Sorel, M; Southwell, L; Stamoulis, P; Steinmann, J; Stewart, T; Suda, Y; Suvorov, S; Suzuki, A; Suzuki, K; Suzuki, S Y; Suzuki, Y; Tacik, R; Tada, M; Takahashi, S; Takeda, A; Takeuchi, Y; Tanaka, H K; Tanaka, H A; Terhorst, D; Terri, R; Thakore, T; Thompson, L F; Tobayama, S; Toki, W; Tomura, T; Touramanis, C; Tsukamoto, T; Tzanov, M; Uchida, Y; Vacheret, A; Vagins, M; Vallari, Z; Vasseur, G; Wachala, T; Wakamatsu, K; Walter, C W; Wark, D; Warzycha, W; Wascko, M O; Weber, A; Wendell, R; Wilkes, R J; Wilking, M J; Wilkinson, C; Wilson, J R; Wilson, R J; Yamada, Y; Yamamoto, K; Yamamoto, M; Yanagisawa, C; Yano, T; Yen, S; Yershov, N; Yokoyama, M; Yoo, J; Yoshida, K; Yuan, T; Yu, M; Zalewska, A; Zalipska, J; Zambelli, L; Zaremba, K; Ziembicki, M; Zimmerman, E D; Zito, M; Żmuda, J

    2016-05-01

    T2K reports its first measurements of the parameters governing the disappearance of ν[over ¯]_{μ} in an off-axis beam due to flavor change induced by neutrino oscillations. The quasimonochromatic ν[over ¯]_{μ} beam, produced with a peak energy of 0.6 GeV at J-PARC, is observed at the far detector Super-Kamiokande, 295 km away, where the ν[over ¯]_{μ} survival probability is expected to be minimal. Using a data set corresponding to 4.01×10^{20} protons on target, 34 fully contained μ-like events were observed. The best-fit oscillation parameters are sin^{2}(θ[over ¯]_{23})=0.45 and |Δm[over ¯]_{32}^{2}|=2.51×10^{-3}  eV^{2} with 68% confidence intervals of 0.38-0.64 and 2.26-2.80×10^{-3}  eV^{2}, respectively. These results are in agreement with existing antineutrino parameter measurements and also with the ν_{μ} disappearance parameters measured by T2K. PMID:27203315

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

    CERN Document Server

    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...

  9. Neutrino-antineutrino Mass Splitting in the Standard Model: Neutrino Oscillation and Baryogenesis

    CERN Document Server

    Fujikawa, Kazuo

    2015-01-01

    By adding a neutrino mass term to the Standard Model, which is Lorentz and $SU(2)\\times U(1)$ invariant but non-local to evade $CPT$ theorem, it is shown that non-locality within a distance scale of the Planck length, that may not be fatal to unitarity in generic effective theory, can generate the neutrino-antineutrino mass splitting of the order of observed neutrino mass differences, which is tested in oscillation experiments, and non-negligible baryon asymmetry depending on the estimate of sphaleron dynamics. The one-loop order induced electron-positron mass splitting in the Standard Model is shown to be finite and estimated at $\\sim 10^{-20}$ eV, well below the experimental bound $< 10^{-2}$ eV. The induced $CPT$ violation in the $K$-meson in the Standard Model is expected to be even smaller and well below the experimental bound $|m_{K}-m_{\\bar{K}}|<0.44\\times 10^{-18}$ GeV.

  10. Contribution of Recently Measured Nuclear Data to Reactor Antineutrino Energy Spectra Predictions

    Energy Technology Data Exchange (ETDEWEB)

    Estienne, M., E-mail: magali.estienne@subatech.in2p3.fr [SUBATECH, CNRS/IN2P3, Université de Nantes, Ecole des Mines de Nantes, F-44307 Nantes (France); Fallot, M.; Cormon, S. [SUBATECH, CNRS/IN2P3, Université de Nantes, Ecole des Mines de Nantes, F-44307 Nantes (France); Algora, A. [IFIC (CSIC-Univ. Valencia), Valencia (Spain); Institute of Nuclear Research, Debrecen (Hungary); Bui, V.M.; Cucoanes, A.; Elnimr, M.; Giot, L. [SUBATECH, CNRS/IN2P3, Université de Nantes, Ecole des Mines de Nantes, F-44307 Nantes (France); Jordan, D. [IFIC (CSIC-Univ. Valencia), Valencia (Spain); Martino, J.; Onillon, A.; Porta, A.; Pronost, G.; Remoto, A. [SUBATECH, CNRS/IN2P3, Université de Nantes, Ecole des Mines de Nantes, F-44307 Nantes (France); Taín, J.L. [IFIC (CSIC-Univ. Valencia), Valencia (Spain); Yermia, F.; Zakari-Issoufou, A.-A. [SUBATECH, CNRS/IN2P3, Université de Nantes, Ecole des Mines de Nantes, F-44307 Nantes (France)

    2014-06-15

    The aim of this work is to study the impact of the inclusion of the recently measured β decay properties of the {sup 102,104,105,106,107}Tc, {sup 105}Mo, and {sup 101}Nb nuclei in the calculation of the antineutrino (anti-ν) energy spectra arising after the fissions of the four main fissile isotopes {sup 235,238}U, and {sup 239,241}Pu in PWRs. These β feeding probabilities, measured using the Total Absorption Technique (TAS) at the JYFL facility of Jyväskylä, have been found to play a major role in the γ component of the decay heat for {sup 239}Pu in the 4-3000 s range. Following the fission product summation method, the calculation was performed using the MCNP Utility Reactor Evolution code (MURE) coupled to the experimental spectra built from β decay properties of the fission products taken from evaluated databases. These latest TAS data are found to have a significant effect on the Pu isotope energy spectra and on the spectrum of {sup 238}U showing the importance of their measurement for a better assessment of the reactor anti-ν energy spectrum, as well as importance for fundamental neutrino physics experiments and neutrino applied physics.

  11. π0, rho0 ω0 production in high energy neutrino and antineutrino interactions

    International Nuclear Information System (INIS)

    The work presented in this thesis is concerned with the hadronic shower in the neutrino and antineutrino interactions of the high energy charged-current type. The π0 particles issued from this hadronic shower are analysed and the rho0 and ω0 production rate are determined in view to try to understand the quark fragmentation process, that is to say the QCD theory relative to the quark confinement problem. The experimental device is described in the chapter II. Chapter III is dealing with the analysis of the exposures obtained with this device, together with the incident neutrino energy determination methods and a general description of the final data characteristics. The π0 production is studied from the decay γ observed in the bubble chamber. The existing different methods are analyzed and compared with the used one. The π0 properties are studied in detail. In chapter 5, the rho0 and ω0 resonance production rate is calculated, using the previous chapter results. Finally, chapter 6 summarizes the thesis conclusions

  12. The diffuse neutrino flux from supernovae: upper limit on the electron neutrino component from the non-observation of antineutrinos at SuperKamiokande

    CERN Document Server

    Lunardini, C

    2006-01-01

    I derive an upper bound on the electron neutrino component of the diffuse supernova neutrino flux from the constraint on the antineutrino component at SuperKamiokande. The connection between antineutrino and neutrino channels is due to the similarity of the muon and tau neutrino and antineutrino fluxes produced in a supernova, and to the conversion of these species into electron neutrinos and antineutrinos inside the star. The limit on the electron neutrino flux is 5.5 cm^-2 s^-1 above 19.3 MeV of neutrino energy, and is stronger than the direct limit from LSD by three orders of magnitude. It represents the minimal sensitivity required at future direct searches, and is intriguingly close to the reach of the SNO and ICARUS experiments. The electron neutrino flux will have a lower bound if the electron antineutrino flux is measured. Indicatively, the first can be smaller than the second at most by a factor of 2-3 depending on the details of the neutrino spectra at production.

  13. Asymmetry in the neutrino and anti-neutrino reactions in a nuclear medium

    International Nuclear Information System (INIS)

    We study the effect of the density-dependent axial and vector form factors on the electron–neutrino (νe) and anti-neutrino (ν¯e) reactions for a nucleon in nuclear matter or in 12C. The nucleon form factors in free space are presumed to be modified for a bound nucleon in a nuclear medium. We adopt the density-dependent form factors calculated by the quark–meson coupling (QMC) model, and apply them to the νe and ν¯e induced reactions with the initial energy E=8–80 MeV. We find that the total νe cross sections on 12C as well as on a nucleon in nuclear matter are reduced by about 5% at the nuclear saturation density, ρ0. This reduction is caused by the modification of the nucleon structure in matter. Although the density effect for both cases is relatively small, it is comparable with the effect of Coulomb distortion on the outgoing lepton in the ν-reaction. In contrast, the density effect on the ν¯e reaction reduces the cross section significantly in both nuclear matter and 12C cases, and the amount maximally becomes of about 35% around ρ0. Such large asymmetry in the νe and ν¯e cross sections, which seems to be nearly independent of the target, is originated from the differences in the helicities of ν¯e and νe. It is expected that the asymmetry influences the r-process and also the neutrino-process nucleosynthesis in core-collapse supernovae

  14. Experimental results on one-pion neutral current reaction in all channels induced by antineutrinos at CERN PS

    Science.gov (United States)

    Erriques, O.; Fogli-Muciaccia, M. T.; Natali, S.; Nuzzo, S.; Halsteinslid, A.; Myklebost, K.; Rognebakke, A.; Bonetti, S.; Cavalli, D.; Pullia, A.; Rollier, M.; Engel, J. P.; Guyonnet, J. L.; Huss, D.; Paty, M.; Riester, J. L.; Gamba, D.; Marzari-Chiesa, A.; Riccati, L.; Romero, A.; Bullock, F. W.; Henderson, R. C. W.; Jones, T. W.

    1980-12-01

    Single pion production, in antineutrino-nucleon interactions via the neutral current, has been studied in the bubble chamber Gargamelle, filled with propane. Complete analysis of the secondaries, including π0,s, has allowed a detailed study of all channels. After background and nuclear corrections, results are obtained which can be interpreted in terms of isospin structure of the neutral weak current and of the Salam-Weinberg angle. Agreement is found with the currently accepted value of sin 2θW and the data suggest an important contribution of I = {3}/{2} final states.

  15. Experimental results on one-pion neutral current reaction in all channels induced by antineutrinos at CERN PS

    CERN Document Server

    Erriquez, O; Bullock, F W; Cavalli, D; Engel, J P; Fogli-Muciaccia, M T; Gamba, D; Guyonnet, J L; Halsteinslid, A; Henderson, R C W; Huss, D; Jones, T W; Marzari-Chiesa, A; Myklebost, K; Natali, S; Nuzzo, S; Paty, M; Pullia, A; Riccati, L; Riester, J L; Rognebakke, A; Rollier, M; Romero, A

    1980-01-01

    Single pion production, in antineutrino-nucleon interactions via the neutral current, has been studied in the bubble chamber Gargamelle, filled with propane. Complete analysis of the secondaries, including pi /sup 0/'s, has allowed a detailed study of all channels. After background and nuclear corrections, results are obtained which can be interpreted in terms of isospin structure of the neutral weak current and of the Salam-Weinberg angle. Agreement is found with the currently accepted value of sin/sup 2/ theta /sub w/ and the data suggest an important contribution of I=/sup 3///sub 2/ final states. (11 refs).

  16. Adaptation of the kinematic program for an antineutrino experiment in the ''HYDRA'' system With the BESM-6 computer

    International Nuclear Information System (INIS)

    A KINEMATIKA program is structurally described and is aimed at kinematic fitting of V0-particles and γ-quanta in each event studied during anti-neutrino experiment. The program contains 17 modules and, due to the fact that it exceeds main memory of the BESM-6 computer, the program has been divided into seven segments. Each segment is briefly described. A computer time to process an event with up to four hypotheses on the type of interaction does not exceed 30-40 seconds

  17. A method for an improved measurement of the electron-antineutrino correlation in free neutron beta decay

    International Nuclear Information System (INIS)

    The angular correlation between the beta electron and antineutrino in nuclear beta decay is characterized by the dimensionless parameter a. The value of a for free neutron decay, when combined with other neutron decay parameters, can be used to determine the weak vector and axial vector coupling constants gV and gA and test the validity and self-consistency of the Electroweak Standard Model. Previous experiments that measured a in neutron decay relied on precise proton spectroscopy and were limited by systematic effects at about the 5% level. We present a new approach to measuring a for which systematic uncertainties promise to be much smaller

  18. Search for sub-eV sterile neutrinos in the precision multiple baselines reactor antineutrino oscillation experiments

    Directory of Open Access Journals (Sweden)

    Shu Luo

    2015-10-01

    Full Text Available According to different effects on neutrino oscillations, the unitarity violation in the MNSP matrix can be classified into the direct unitarity violation and the indirect unitarity violation which are induced by the existence of the light and the heavy sterile neutrinos respectively. Of which sub-eV sterile neutrinos are of most interesting. We study in this paper the possibility of searching for sub-eV sterile neutrinos in the precision reactor antineutrino oscillation experiments with three different baselines at around 500 m, 2 km and 60 km. We find that the antineutrino survival probabilities obtained in the reactor experiments are sensitive only to the direct unitarity violation and offer very concentrated sensitivity to the two parameters θ14 and Δm412. If such light sterile neutrinos do exist, the active–sterile mixing angle θ14 could be acquired by the combined rate analysis at all the three baselines and the mass-squared difference Δm412 could be obtained by taking the Fourier transformation to the L/E spectrum. Of course, for such measurements to succeed, both high energy resolution and large statistics are essentially important.

  19. Global Analysis of the Source and Detector Nonstandard Interactions Using the Short Baseline Neutrino- and Antineutrino-Electron Scattering Data

    CERN Document Server

    Khan, Amir N

    2016-01-01

    We present a global analysis of the semileptonic and purely Leptonic nonuniversal and flavor-changing nonstandard neutrino interactions in all the known short-baseline neutrino- and antineutrino-electron scattering experiments. The nonstandard effects at the source and at the detector can be more transparent in these experiments because of the negligibly small ratio between the baselines and the neutrino energies, which is not enough for the neutrinos to oscillate, and thus can be sensitive to the new physics at the both ends. We use data from two electron-neutrino electron scattering experiments and six electron-antineutrino electron scattering experiments and combine them to find the best fits on the nonstandard parameters using the source-only, detector-only analyses, and then find the interplay between the two cases. The bounds obtained in some cases are stronger and new, in some cases comparable to the current ones, and in the other cases weaker. For instance, the bound obtained from the interplay betwee...

  20. Messung der Impulsverteilung der Antiquarks im Nukleon aus der inklusiven tiefinelastischen Antineutrino Nukleon Reaktion ueber geladene Stroeme

    CERN Document Server

    Klasen, Hans Peter

    1981-01-01

    In this thesis the antiquark momentum distribution in the nucleus as a function of x and Q2 is determined. This determination is based on the measurement of the differential cross-section at high y for inclusive antineutrino nucleon charged current interactions. The portion of antineutrino scattering off quarks is corrected by the also measured neutrino cross-section. For the measurement of the cross-section 150 000 anti v- und 35 000 v-events, which were produced in the CERN wide band beam, in the energy range from 20 GeV to 160 GeV and 27 000 anti v- and 63 000 v-events measured in the narrow band beam in the energy range from 20 GeV to 200 GeV are used. The measurement was performed with the detector of the CERN-Dortmund-Heidelberg-Saclay collaboration. The detector serves at the same time as target, as hadron energy calorimeter and as muon spectrometer. The measured antiquark momentum distribution shows a strong rise for x<0.1 as a function of Q2. It will be shown that this scaling violation cannot be ...

  1. Measurement of the mixing leptonic parameter θ13 at the Double Chooz reactor antineutrino experiment

    International Nuclear Information System (INIS)

    The Double Chooz experiment aims at measuring the neutrino mixing parameter θ13 by studying the oscillations of de ν-bare produced by the Chooz nuclear reactors located in France. The experimental concept consists in comparing the signal of two identical 10.3 m3 detectors, allowing to cancel most of the experimental systematic uncertainties. The near detector, whose goal is the flux normalization and a measurement without oscillation, is expected to be delivered in 2013. The farthest detector from the source is taking data since April 2011 and is sensitive to θ13, which is expected to affect both the rate and the shape of the measured de ν-bare. In this thesis, are first presented the Double Chooz experiment, with its ν-bare source, its detection method, and the expected signal and backgrounds. In order to perform a selection, important quantities have to be reconstructed, calibrated, and saved in data files. The channel time offsets determination, the energy and vertex reconstruction algorithm CocoReco, the reconstruction packages of the Common Trunk, and the light trees maker Cheetah are especially presented. Concerning the data analysis, all the selection cuts and results for signal and backgrounds are discussed, particularly the multiplicity cut, the multiple off time window method, the lithium veto cut, and the cosmogenic 9Li background studies. The Double Chooz experiment observed 8,249 de -bare candidates in 227.93 days in its far detector only. The reactor antineutrino flux prediction used the Bugey 4 flux measurement after correction for differences in core composition. The expectation in case of no-oscillation is 8,937 events and this deficit is interpreted as evidence for ν-bare disappearance. From a rate and shape analysis, is found sin22θ = 0,109± 0,030 (stat) ± 0,025 (syst), with Δm231 = 2,32 x 10-3 eV2, while the no-oscillation hypothesis is even excluded at 2.9 σ. (author)

  2. Anti-Neutrino Charged Current Quasi-Elastic Scattering in MINER$\

    Energy Technology Data Exchange (ETDEWEB)

    Chvojka, Jesse John [Univ. of Rochester, NY (United States)

    2012-01-01

    in neutrino interactions. We present the first cross-section measurement for MINER A, the differential cross-section dσ/dQ2 for muon anti-neutrino CCQE scattering on polystyrene scintillator (CH) as well as comparisons to several final state models.

  3. Effects of Fission Yield Data in the Calculation of Antineutrino Spectra for 235U (n ,fission) at Thermal and Fast Neutron Energies

    Science.gov (United States)

    Sonzogni, A. A.; McCutchan, E. A.; Johnson, T. D.; Dimitriou, P.

    2016-04-01

    Fission yields form an integral part of the prediction of antineutrino spectra generated by nuclear reactors, but little attention has been paid to the quality and reliability of the data used in current calculations. Following a critical review of the thermal and fast ENDF/B-VII.1 235U 235 fission yields, deficiencies are identified and improved yields are obtained, based on corrections of erroneous yields, consistency between decay and fission yield data, and updated isomeric ratios. These corrected yields are used to calculate antineutrino spectra using the summation method. An anomalous value for the thermal fission yield of 86Ge generates an excess of antineutrinos at 5-7 MeV, a feature which is no longer present when the corrected yields are used. Thermal spectra calculated with two distinct fission yield libraries (corrected ENDF/B and JEFF) differ by up to 6% in the 0-7 MeV energy window, allowing for a basic estimate of the uncertainty involved in the fission yield component of summation calculations. Finally, the fast neutron antineutrino spectrum is calculated, which at the moment can only be obtained with the summation method and may be relevant for short baseline reactor experiments using highly enriched uranium fuel.

  4. Effects of Fission Yield Data in the Calculation of Antineutrino Spectra for ^{235}U(n,fission) at Thermal and Fast Neutron Energies.

    Science.gov (United States)

    Sonzogni, A A; McCutchan, E A; Johnson, T D; Dimitriou, P

    2016-04-01

    Fission yields form an integral part of the prediction of antineutrino spectra generated by nuclear reactors, but little attention has been paid to the quality and reliability of the data used in current calculations. Following a critical review of the thermal and fast ENDF/B-VII.1 ^{235}U fission yields, deficiencies are identified and improved yields are obtained, based on corrections of erroneous yields, consistency between decay and fission yield data, and updated isomeric ratios. These corrected yields are used to calculate antineutrino spectra using the summation method. An anomalous value for the thermal fission yield of ^{86}Ge generates an excess of antineutrinos at 5-7 MeV, a feature which is no longer present when the corrected yields are used. Thermal spectra calculated with two distinct fission yield libraries (corrected ENDF/B and JEFF) differ by up to 6% in the 0-7 MeV energy window, allowing for a basic estimate of the uncertainty involved in the fission yield component of summation calculations. Finally, the fast neutron antineutrino spectrum is calculated, which at the moment can only be obtained with the summation method and may be relevant for short baseline reactor experiments using highly enriched uranium fuel. PMID:27081973

  5. Muon storage rings for a beam-systematic-free measurement of neutrino and antineutrino cross-sections at low energy

    CERN Document Server

    Navas-Concha, S

    2002-01-01

    Precision neutrino cross-section measurements at low energies will be necessary to improve the results of the current and future big neutrino experiments. In order to achieve precision neutrino cross- sections, that will yield a comprehensive understand of the underlying physics, a rather extended program will be required: (1) measurement from kinematical thresholds up to a few GeV; (2) well known and controlled neutrino flux; (3) study of neutrinos and antineutrinos and possibly nu /sub e/ and nu /sub mu / flavors; (4) on several nuclear target; (5) with detectors capable of exclusive final state reconstruction. While the "standard" choice advocated relies on currently existing or on future "traditional" neutrino beams, that will provide very high intensities at near sites, we advocate that neutrinos from muon storage rings provide a better choice to criterias (1)-(3). The currently available statistics from the CERN AD and the FNAL-Debuncher would provide statistical precisions better than 10% in typ. 200 M...

  6. Anharmonicity of internal atomic oscillation and effective antineutrino mass evaluation from gaseous molecular tritium β-decay

    Science.gov (United States)

    Lokhov, Alexey V.; Titov, Nikita A.

    2016-07-01

    Data analysis of the next-generation effective antineutrino mass measurement experiment KATRIN requires reliable knowledge of systematic corrections. In particular, the width of the daughter molecular ion excitation spectrum rovibrational band should be known with better than 1% precision. Very precise ab initio quantum calculations exist, and we compare them with the well-known tritium molecule parameters within the framework of a phenomenological model. The rovibrational band width with accuracy of a few percent is interpreted as a result of the zero-point atomic oscillation in the harmonic potential. The Morse interatomic potential is used to investigate the impact of anharmonic atomic oscillations. The calculated corrections cannot account for the difference between the ab initio quantum calculations and the phenomenological model.

  7. Electron Antineutrino Disappearance at KamLAND and JUNO as Decisive Tests of the Short Baseline Anti-nu_mu to Anti-nu_e Appearance Anomaly

    CERN Document Server

    Conrad, J M

    2013-01-01

    The IsoDAR antineutrino source, which produces a flux from 8Li isotope decay at rest, when paired with the proposed JUNO (Jiangmen Underground Neutrino Observatory) detector, has unprecedented sensitivity to anti-nu_e disappearance for oscillations at high Delta m^2. Assuming CPT invariance, the sensitive region for anti-nu_e disappearance can be used to restrict the allowed parameter space of an anti-nu_mu to anti-nu_e appearance signal. The 5 sigma sensitivity of this experiment covers the entire anti-nu_mu to anti-nu_e allowed parameter space from a combined fit to short-baseline experiments. This represents a decisive test of the LSND and MiniBooNE antineutrino appearance signals within all models that are $CPT$ invariant. Running IsoDAR at KamLAND restricts a large part of the appearance signal region in a similar way.

  8. Analytical orbit calculation of the INS air-core π√2 β-ray spectrometer for the measurement of electron anti-neutrino mass

    International Nuclear Information System (INIS)

    For the measurement of electron anti-neutrino rest mass with the INS air-core(iron-free) β-ray spectrometer, the orbit calculations were carried out for the case of simultaneous use of an extended source and a position-sensitive electron counter. Analytical calculation up to the 3rd-order approximation results in design parameters of 16cm x 7cm source area, 0.095% transmission, 4% momentum acceptance and 67.60 and 4.190 tilt angles of the source and the detector planes, respectively, for 0.05% momentum resolution. These values imply a 7 times larger sensitivity to the electron anti-neutrino mass than in the recent experiment by ITEP group. (author)

  9. Off-shell effects in the relativistic mean field model and their role in CC (anti)neutrino scattering at MiniBooNE kinematics

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, M.V., E-mail: martin.inrne@gmail.com [Grupo de Física Nuclear, Departamento de Física Atómica, Molecular y Nuclear, Facultad de Ciencias Físicas, Universidad Complutense de Madrid, CEI Moncloa, Madrid E-28040 (Spain); Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, Sofia 1784 (Bulgaria); González-Jiménez, R.; Caballero, J.A. [Departamento de Física Atómica, Molecular y Nuclear, Universidad de Sevilla, 41080 Sevilla (Spain); Barbaro, M.B. [Dipartimento di Fisica, Università di Torino and INFN, Sezione di Torino, Via P. Giuria 1, 10125 Torino (Italy); Donnelly, T.W. [Center for Theoretical Physics, Laboratory for Nuclear Science and Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Udías, J.M. [Grupo de Física Nuclear, Departamento de Física Atómica, Molecular y Nuclear, Facultad de Ciencias Físicas, Universidad Complutense de Madrid, CEI Moncloa, Madrid E-28040 (Spain)

    2013-11-25

    The relativistic mean field (RMF) model is used to describe nucleons in the nucleus and thereby to evaluate the effects of having dynamically off-shell spinors. Compared with free, on-shell nucleons as employed in some other models, within the RMF nucleons are described by relativistic spinors with strongly enhanced lower components. In this work it is seen that for MiniBooNE kinematics, neutrino charged-current quasielastic cross sections show some sensitivity to these off-shell effects, while for the antineutrino-nucleus case the total cross sections are seen to be essentially independent of the enhancement of the lower components. As was found to be the case when comparing the RMF results with the neutrino-nucleus data, the present impulse approximation predictions within the RMF also fall short of the MiniBooNE antineutrino-nucleus data.

  10. Les expériences Nucifer et Stéréo : étude des antineutrinos de réacteurs à courte distance

    OpenAIRE

    Pequignot, Maxime

    2015-01-01

    In spite of a faint interaction with their environment, neutrinos can be now clearly detected thanks to a proven technology based on liquid scintillators and photomultiplier tubes. The advances made these last years allow to reduce the size and the complexity of the detectors and therefore naturally lead to the first applications with these particles. As the first experiment to be placed at 7.2 m of a nuclear core, the Nucifer detector demonstrates the possibility of counting antineutrinos co...

  11. CeLAND: search for a 4th light neutrino state with a 3 PBq 144Ce-144Pr electron antineutrino generator in KamLAND

    CERN Document Server

    Gando, A; Hayashida, S; Ikeda, H; Inoue, K; Ishidoshiro, K; Ishikawa, H; Koga, M; Matsuda, R; Matsuda, S; Mitsui, T; Motoki, D; Nakamura, K; Oki, Y; Otani, M; Shimizu, I; Shirai, J; Suekane, F; Suzuki, A; Takemoto, Y; Tamae, K; Ueshima, K; Watanabe, H; Xu, B D; Yamada, S; Yamauchi, Y; Yoshida, H; Cribier, M; Durero, M; Fischer, V; Gaffiot, J; Jonqueres, N; Kouchner, A; Lasserre, T; Leterme, D; Letourneau, A; Lhuillier, D; Mention, G; Rampal, G; Scola, L; Veyssiere, Ch; Vivier, M; Yala, P; Berger, B E; Kozlov, A; Banks, T; Dwyer, D; Fujikawa, B K; Han, K; Kolomensky, Yu G; Mei, Y; O'Donnell, T; Decowski, P; Markoff, D M; Yoshida, S; Kornoukhov, V N; Gelis, T V M; Tikhomirov, G V; Learned, J G; Maricic, J; Matsuno, S; Milincic, R; Karwowski, H J; Efremenko, Y; Detwiler, A; Enomoto, S

    2013-01-01

    The reactor neutrino and gallium anomalies can be tested with a 3-4 PBq (75-100 kCi scale) 144Ce-144Pr antineutrino beta-source deployed at the center or next to a large low-background liquid scintillator detector. The antineutrino generator will be produced by the Russian reprocessing plant PA Mayak as early as 2014, transported to Japan, and deployed in the Kamioka Liquid Scintillator Anti-Neutrino Detector (KamLAND) as early as 2015. KamLAND's 13 m diameter target volume provides a suitable environment to measure the energy and position dependence of the detected neutrino flux. A characteristic oscillation pattern would be visible for a baseline of about 10 m or less, providing a very clean signal of neutrino disappearance into a yet-unknown, sterile neutrino state. This will provide a comprehensive test of the electron dissaperance neutrino anomalies and could lead to the discovery of a 4th neutrino state for Delta_m^2 > 0.1 eV^2 and sin^2(2theta) > 0.05.

  12. Precise Measurement of Dimuon Production Cross-Sections in muon neutrino Fe and muon antineutrino Fe Deep Inelastic Scattering at the Tevatron

    CERN Document Server

    Goncharov, M; Alton, A; Bolton, T; Goldman, J; Spentzouris, P; Conrad, J; Fleming, B T; Formaggio, J A; Koutsoliotas, S; Kim, J H; McNulty, C; Romosan, A; Shaevitz, M H; Stern, E G; Vaitaitis, A G; Zimmerman, E D; Johnson, R A; Vakili, M; Suwonjandee, N; Bernstein, R H; Bugel, L; Lamm, M J; Marsh, W; Nienaber, P; Yu, J; De Barbaro, L; Buchholz, D; Schellman, H; Zeller, G P; Brau, J E; Drucker, R B; Frey, R; Mason, D; McDonald, J E; Naples, D; Tzanov, M; Avvakumov, S; De Barbaro, P; Bodek, Arie; Budd, H S; Harris, D A; McFarland, K S; Sakumoto, W K; Yang, U K

    2001-01-01

    We present measurements of the semi-inclusive cross-sections for muon neutrino and muon antineutrino-nucleon deep inelastic scattering interactions with two oppositely charged muons in the final state. These events dominantly arise from production of a charm quark during the scattering process. The measurement was obtained from the analysis of 5102 muon neutrino-induced and 1458 muon antineutrino-induced events collected with the NuTeV detector exposed to a sign-selected beam at the Fermilab Tevatron. We also extract a cross-section measurement from a re-analysis of 5030 muon neutrino-induced and 1060 muon antineutrino-induced vents collected from the exposure of the same detector to a quad-triplet beam by the CCFR experiment. The results are combined to obtain the most statistically precise measurement of neutrino-induced dimuon production cross-sections to date. These measurements should be of broad use to phenomenologists interested in the dynamics of charm production, the strangeness content of the nucleo...

  13. Measurement of Neutrino and Antineutrino Charged-Current Inclusive Cross Sections with the MINERvA Detector

    Energy Technology Data Exchange (ETDEWEB)

    Devan, Joshua D. [College of William and Mary, Williamsburg, VA (United States)

    2015-01-01

    Neutrinos are a nearly massless, neutral particle in the Standard Model that only interact via the weak interaction. Experimental confirmation of neutrino oscillations, in which a neutrino created as a particular type (electron, muon or tau) can be observed as a different type after propagating some distance, earned the 2015 Nobel Prize in Physics. Neutrino oscillation experiments rely on accurate measurements of neutrino interactions with matter, such as that presented here. Neutrinos also provide a unique probe of the nucleus, complementary to electron scattering experiments. This thesis presents a measurement of the charged-current inclusive cross section for muon neutrinos and antineutrinos in the energy range 2 to 50 GeV with the MINERvA detector. MINERvA is a neutrino scattering experiment in the NuMI neutrino beam at Fermilab, near Chicago. A cross section measures the probability of an interaction occurring, measured here as a function of neutrino energy. To extract a cross section from data, the observed rate of interactions is corrected for detector efficiency and divided by the number of scattering nucleons in the target and the flux of neutrinos in the beam. The neutrino flux is determined with the low-$\

  14. A computer study of the experimental feasibility of observing the nuclear excitation of 7Li by reactor antineutrinos

    Science.gov (United States)

    Avignone, F. T.; Donnelly, T. W.

    1981-01-01

    A computer study of the feasibility of observing the 0.478 MeV γ-ray following the antineutrino excitation of 7Li has been carried out in a simple geometry involving two large Ge detectors placed on the axis inside a 20 kg target of natural lithium. The background γ-ray flux was assumed to be that observed by Fiorini and his co-workers in their search for neutrinoless double beta decay of 76Ge. The target was assumed to be inside a rectangular live shield of NaI(Tl) which has a wall thickness of 10.16 cm. The results for the Weinberg-Salam model clearly show that the direct observation of this reaction is feasible even if the background is almost two orders of magnitude more intense than the background observed by Fiorini et al. This conclusion was found to be valid even if most of the background originates inside the cryostat itself. If the background is no more than three times as intense as that observed by Fiorini et al., the excitation can at least be observed with a larger target and with no NaI(Tl) annulus.

  15. Neutral current quasielastic (anti)neutrino scattering beyond the Fermi gas model at MiniBooNE and BNL kinematics

    CERN Document Server

    Ivanov, M V; Barbaro, M B; Giusti, C; Meucci, A; Caballero, J A; Gonzalez-Jimenez, R; de Guerra, E Moya; Udias, J M

    2015-01-01

    Neutral current quasielastic (anti)neutrino scattering cross sections on a $^{12}$C target are analyzed using a realistic spectral function $S(p,E)$ that gives a scaling function in accordance with the ($e,e'$) scattering data. The spectral function accounts for the nucleon-nucleon (NN) correlations by using natural orbitals (NOs) from the Jastrow correlation method and has a realistic energy dependence. The standard value of the axial mass $M_A= 1.032$ GeV is used in all calculations. The role of the final-state interaction (FSI) on the spectral and scaling functions, as well as on the cross sections is accounted for. A comparison of the calculations with the empirical data of the MiniBooNE and BNL experiments is performed. Our results are analyzed in comparison with those when NN correlations are not included, and also with results from other theoretical approaches, such as the relativistic Fermi gas (RFG), the relativistic mean field (RMF), the relativistic Green's function (RGF), as well as with the Super...

  16. Measurements of cross-section of charge current inclusive of antineutrino scattering off nucleons using carbon, iron, lead and scintillator at MINER$\

    Energy Technology Data Exchange (ETDEWEB)

    Rakotondravohitra, Laza [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2015-08-18

    Neutrino physics is one of the most active fields in the domaine of high energy physics during the last century. The need of precise measurement of neutrino-nucleus interactions required by the neutrino oscillation experiments is a an exiting step. These measurements of cross-section are more than essential for neutrino oscillation experiment. Over the year, many measurements from varieties of experiments have been presented. MINERνA is one of the world leaders in measuring cross-section of neutrino and antineutrino -nucleus interactions. MINERνA is a neutrino-nucleus scattering experiment installed in the few-GeV NuMI beam line at Fermilab. In order to study nuclear dependence, MINERνA is endowed with different types of solid nuclear targets as well are liquid targets such as helium and water. This thesis presents measurements of cross-section of antineutrino scattering off nucleons using a variety of solid nuclear targets, carbon, iron, lead and also polystyrene scintillator (CH). The data set of antineutrino used for this analysis was taken between March and July 2010 with a total of 1.60X1020 protons on target. Charged current inclusive interactions were selected by requiring a positive muon and kinematics limitation of acceptance of the muon spectrometer are applied. The analysis requires neutrino energy between 2GeV et 20GeV and the angle of muon θmu < 17degree . The absolute cross-section # as function of neutrino energy and the differential cross-section dσ/ dxbj measured and shown the corresponding systematics for each nuclear targets. Data results are compared with prediction of the models implemented in the neutrino events generators GENIE 2.6.2 used by the experiment.

  17. Reactor anti-neutrinos: measurement of the θ13 leptonic mixing angle and search for potential sterile neutrinos

    International Nuclear Information System (INIS)

    The Double Chooz experiment aims to measure the θ13 mixing angle through the disappearance -induced by the oscillation phenomenon - of anti-neutrinos produced by the Chooz nuclear reactors. In order to reduce systematic uncertainties, the experiment relies on the relative comparison of detected signals in two identical liquid scintillator detectors. The near one, giving the normalization of the emitted flux, is currently being built and will be delivered in spring 2014. The far detector, sensitive to θ13, is located at about one kilometer and is taking data since 2011. In this first phase of the experiment, the far detector data are compared to a prediction of the emitted neutrino flux to estimate θ13. In this thesis, the Double Chooz experiment and its analysis are presented, especially the background studies and the rejection of parasitic signals due to light emitted by photo-multipliers. Neutron fluxes between the different detector volumes impact the definition of the fiducial volume of neutrino interactions and the efficiency of detection. Detailed studies of these effects are presented. As part of the Double Chooz experiment, studies were performed to improve the prediction of neutrino flux emitted by reactors. This work revealed a deficit of observed neutrino rates in the short baseline experiments of last decades. This deficit could be explained by an oscillation to a sterile state. The Stereo project aims to observe a typical signature of oscillations: the distortion of neutrino spectra both in energy and baseline. This thesis presents the detector concept and simulations as well as sensitivity studies. Background sources and the foreseen shielding are also discussed. (author)

  18. Study of the prospective usefulness of the detection of antineutrinos to monitor nuclear power plants for non proliferation purpose

    International Nuclear Information System (INIS)

    The field of applied neutrino physics has shown new developments in the last decade. Indeed, the antineutrinos (ne) emitted by a nuclear power plant depend on the composition of the fuel: thus their detection could be exploited for determining the isotopic composition of the reactor fuel. The International Atomic Energy Agency (IAEA) has expressed its interest in the potentialities of this detection as a new safeguard tool and has created an Ad Hoc working group devoted to this study. Our aim is to determine on the one hand, the current sensitivity reached with the ne detection and on the other hand, the sensitivity required to be useful to the IAEA and then we deduce the required performances required for a cubic meter detector. We will first present the physics on which our feasibility study relies: the neutrinos, the b-decay of the fission products (FP) and their conversion into ne spectra. We will then present our simulation tools: we use a package called MCNP Utility for Reactor Evolution (MURE), initially developed by CNRS/IN2P3 labs to study Generation IV reactors. Thanks to MURE coupled with nuclear data bases, we build the ne spectra by summing the FP contributions. The method is the only one that allows the ne spectra calculations associated to future reactors: we will present the predicted spectra for various innovative fuels. We then calculate the emitted ne associated to various concepts of current and future nuclear reactors in order to determine the sensitivity of the ne probe to various diversion scenarios, taking neutronics into account. The reactor studied are Canadian Deuterium, Pebble Bed Reactor and Fast Breeder Reactor. (author)

  19. Neutron radiative capture reactions on nuclei of relevance to 0νββ, dark matter and neutrino/antineutrino searches

    Directory of Open Access Journals (Sweden)

    Tornow W.

    2015-01-01

    Full Text Available A program is underway at the Triangle Universities Nuclear Laboratory (TUNL to measure the neutron capture cross section in the 0.5 to 15 MeV energy range on nuclei whose radioactive daughters could potentially create backgrounds in searches for rare events. Here, we refer to neutrino-less double-beta decay and dark-matter searches, and to detectors built for neutrino and/or antineutrino studies. Neutron capture cross-section data obtained by using the activation method are reported for 40Ar, 74,76Ge, 128,130Te and 136Xe and compared to model calculations and evaluations.

  20. Electron Antineutrino Disappearance at KamLAND and JUNO as Decisive Tests of the Short Baseline Anti-nu_mu to Anti-nu_e Appearance Anomaly

    OpenAIRE

    Conrad, J. M.; Shaevitz, M. H.

    2013-01-01

    The IsoDAR antineutrino source, which produces a flux from 8Li isotope decay at rest, when paired with the proposed JUNO (Jiangmen Underground Neutrino Observatory) detector, has unprecedented sensitivity to anti-nu_e disappearance for oscillations at high Delta m^2. Assuming CPT invariance, the sensitive region for anti-nu_e disappearance can be used to restrict the allowed parameter space of an anti-nu_mu to anti-nu_e appearance signal. The 5 sigma sensitivity of this experiment covers the ...

  1. Probing of the neutrino magnetic moment at the level of 10-22 μB with an intense tritium source of (anti)neutrino and helium target (project)

    International Nuclear Information System (INIS)

    We present research results of the preparation project for the experimental measurement of the (anti)neutrino magnetic moment at the level of 10-12 μB using an intense tritium source of antineutrinos and a liquid helium scintillation detector. The neutrino detection in the scintillation detector is based on the scattering of neutrinos by the electrons of the helium atoms that produces fast electrons able to ionize and exciting helium atoms. The detection of the atomic radiation emitted during the relaxation process of the helium atoms and the knowledge of its parameters will allow us to conclude on the neutrino properties

  2. Probing of the neutrino magnetic moment at the level of 10{sup -22} μ{sub B} with an intense tritium source of (anti)neutrino and helium target (project)

    Energy Technology Data Exchange (ETDEWEB)

    Martemyanov, V.P.; Aleshin, V.I.; Tarasenko, V.G.; Tsinoev, V.G.; Sabelnikov, A.A. [NRC Kurchatov Institute, Moscow (Russian Federation); Yukhimchuk, A.A.; Popov, V.V.; Baluev, V.V.; Golubkov, A.N.; Klevtsov, V.G.; Kuryakin, A.V.; Sitdikov, D.T. [RFNC VNIIEF, Sarov (Russian Federation); Bogdanova, L.N. [SSC RF ITEP, Moscow (Russian Federation)

    2015-03-15

    We present research results of the preparation project for the experimental measurement of the (anti)neutrino magnetic moment at the level of 10{sup -12} μ{sub B} using an intense tritium source of antineutrinos and a liquid helium scintillation detector. The neutrino detection in the scintillation detector is based on the scattering of neutrinos by the electrons of the helium atoms that produces fast electrons able to ionize and exciting helium atoms. The detection of the atomic radiation emitted during the relaxation process of the helium atoms and the knowledge of its parameters will allow us to conclude on the neutrino properties.

  3. Measurement of neutrino mixing angle θ13 and mass difference Δ mee2 from reactor antineutrino disappearance in the RENO experiment

    Science.gov (United States)

    Kim, Soo-Bong

    2016-07-01

    RENO (Reactor Experiment for Neutrino Oscillation) made a definitive measurement of the smallest neutrino mixing angle θ13 in 2012, based on the disappearance of reactor electron antineutrinos. The experiment has obtained a more precise value of the mixing angle and the first result on neutrino mass difference Δ mee2 from an energy and baseline dependent reactor neutrino disappearance using ∼500 days of data. Based on the ratio of inverse-beta-decay (IBD) prompt spectra measured in two identical far and near detectors, we obtain sin2 ⁡ (2θ13) = 0.082 ± 0.009 (stat .) ± 0.006 (syst .) and | Δ mee2 | = [2.62-0.23+0.21 (stat .)-0.13+0.12 (syst .) ] ×10-3 eV2. An excess of reactor antineutrinos near 5 MeV is observed in the measured prompt spectrum with respect to the most commonly used models. The excess is found to be consistent with coming from reactors. A successful measurement of θ13 is also made in an IBD event sample with a delayed signal of neutron capture on hydrogen. A precise value of θ13 would provide important information on determination of the leptonic CP phase if combined with a result of an accelerator neutrino beam experiment.

  4. A PRECISION MEASUREMENT OF THE NEUTRINO MIXING ANGLE THETA (SUB 13) USING REACTOR ANTINEUTRINOS AT DAYA BAY.

    Energy Technology Data Exchange (ETDEWEB)

    KETTELL, S.; ET AL.

    2006-10-16

    This document describes the design of the Daya Bay reactor neutrino experiment. Recent discoveries in neutrino physics have shown that the Standard Model of particle physics is incomplete. The observation of neutrino oscillations has unequivocally demonstrated that the masses of neutrinos are nonzero. The smallness of the neutrino masses (<2 eV) and the two surprisingly large mixing angles measured have thus far provided important clues and constraints to extensions of the Standard Model. The third mixing angle, {delta}{sub 13}, is small and has not yet been determined; the current experimental bound is sin{sup 2} 2{theta}{sub 13} < 0.17 at 90% confidence level (from Chooz) for {Delta}m{sub 31}{sup 2} = 2.5 x 10{sup -3} eV{sup 2}. It is important to measure this angle to provide further insight on how to extend the Standard Model. A precision measurement of sin{sup 2} 2{theta}{sub 13} using nuclear reactors has been recommended by the 2004 APS Multi-divisional Study on the Future of Neutrino Physics as well as a recent Neutrino Scientific Assessment Group (NUSAG) report. We propose to perform a precision measurement of this mixing angle by searching for the disappearance of electron antineutrinos from the nuclear reactor complex in Daya Bay, China. A reactor-based determination of sin{sup 2} 2{theta}{sub 13} will be vital in resolving the neutrino-mass hierarchy and future measurements of CP violation in the lepton sector because this technique cleanly separates {theta}{sub 13} from CP violation and effects of neutrino propagation in the earth. A reactor-based determination of sin{sup 2} 2{theta}{sub 13} will provide important, complementary information to that from long-baseline, accelerator-based experiments. The goal of the Daya Bay experiment is to reach a sensitivity of 0.01 or better in sin{sup 2} 2{theta}{sub 13} at 90% confidence level.

  5. Reactor antineutrino experiments

    CERN Document Server

    Lu, Haoqi

    2014-01-01

    Neutrinos are elementary particles in the standard model of particle physics. There are 3 flavors of neutrinos that oscillate among themselves. Their oscillation can be described by a 3$\\times$3 unitary matrix, containing three mixing angles $\\theta_{12}$, $\\theta_{23}$, $\\theta_{13}$, and one CP phase. Both $\\theta_{12}$ and $\\theta_{23}$ are known from previous experiments. $\\theta_{13}$ was unknown just two years ago. The Daya Bay experiment gave the first definitive non-zero value in 2012. An improved measurement of the oscillation amplitude $\\sin^{2}2(\\theta_{13})$ = $0.090^{+0.008}_{-0.009}$ and the first direct measurement of the $\\bar\

  6. New measurements of the antineutrino-spin asymmetry in beta decay of the neutron and restrictions on the mass of a right-handed gauge boson

    International Nuclear Information System (INIS)

    The results of new measurements of the neutron antineutrino spin asymmetry coefficient B in the beta decay of polarized neutrons are considered. The measurements were carried out on the polarized neutron vertical channel of the WWR-M-Gatchina reactor. Basing on the combination of the results of measurements of the observed asymmetry P · B 0.6617 ± 0.0044 with those of the measurements on the neutron beam polarization P = (66.88 ± 0.22)% the value B = 0.9894 ± 0.0083 is obtained. This value implies that the mass of a hypothetical right-handed charged gauge boson in the left-right symmetric model of the weak interaction is greater than 281 GeV/c2 (90% CL). The conclusion on the agreement of this value with restrictions from muon decay and direct searches for an additional vector boson W is made. 9 refs., 1 tab., 5 figs

  7. Determination of the nucleon structure functions in the study of the inclusive charged current interactions of neutrinos and antineutrinos in iron between 30 and 200 GeV

    International Nuclear Information System (INIS)

    In the deep inelastic neutrino scattering experiment of the CERN-Dortmund-Heidelberg-Saclay collaboration realized on the CERN SPS narrow band beam, we have measured 23000 charged current neutrino and 6200 antineutrino interactions. The structure functions of the nucleon have been extracted from the differential cross sections on iron and compared with parton model predictions. The total cross sections and the fraction of momentum carried by the antiquarks in the nucleon have been measured as function of the neutrino energy. The structure functions obtained for different Q2 bins show significant deviations from scale invariance. The data are in agreement with QCD predictions for a value of the scale parameter Λ between 300 and 700 MeV

  8. Measurement of the neutral to charged current cross section ratios in neutrino and antineutrino nucleon interactions and determination of the Weinberg angle

    International Nuclear Information System (INIS)

    The cross section ratios of neutral and charged current interactions induced by neutrinos and antineutrinos in iron have been measured in the 200 GeV narrow-band beam at the CERN SPS. We find Rsub(ν)=0.301+-0.007 and Rsub(anti ν)=0.363+-0.015 for a hadron energy cut of 10 GeV. The results are in agreement with the standard model of electroweak interactions. In the MS renormalization scheme at the scale of the W boson mass sin2Osub(w)(msub(w))=0.226+-0.012 is obtained, where the error represents the experimental uncertainty. The theoretical uncertainty is estimated to be Δ sind2Osub(w)=+-0.006. (orig.)

  9. Electron antineutrino disappearance at KamLAND and JUNO as decisive tests of the short baseline ν stretchy="false">¯μ→ν stretchy="false">¯e appearance anomaly

    Science.gov (United States)

    Conrad, J. M.; Shaevitz, M. H.

    2014-03-01

    The IsoDAR antineutrino source, which produces a flux from Li8 isotope decay at rest, when paired with the proposed Jiangmen Underground Neutrino Observatory detector, has unprecedented sensitivity to ν ¯e disappearance for oscillations at high Δm2. Assuming charge conjugation, parity transformation, and time reversal (CPT) invariance, the sensitive region for ν ¯e disappearance can be used to restrict the allowed parameter space of a ν ¯μ→ν ¯e appearance signal. The 5σ sensitivity of this experiment covers the entire ν ¯μ→ν ¯e allowed parameter space from a combined fit to short-baseline experiments. This represents a decisive test of the LSND neutrino experiment and MiniBooNE antineutrino appearance signals within all models that are CPT invariant. Running IsoDAR at KamLAND restricts a large part of the appearance signal region in a similar way.

  10. The measurement of the total cross section for deep inelastic neutrino-iron and antineutrino-iron reactions with charge exchange

    International Nuclear Information System (INIS)

    The cross section for deep inelastic neutrino-iron and antineutrino-iron charge-exchange reactions was determined. The experiment was performed in the CERN-NBB at hadron beam momenta of 100 GeV/c, 160 GeV/c, and 200 GeV/c with both polarities. The events were registrated with the improved CDHS detector. The flux determination ensued indirectly via the measurement of the hadron flux respectively the muon flux. The neutrino flux determined by both methods agrees well. Within the accessible neutrino energy range (10 GeV ν ν = 0.331±0.003±0.009 ( . 10-38 cm2 (nucl. . GeV)-1), σν/Eν = 0.703±0.002±0.019 ( . 10-38 cm2 (nucl. . GeV)-1), and σ sub(anti ν)/σν = 0.471±0.005±0.007. The first error indication means the statistical, the second the systematical error. The systematic error is mainly conditioned by uncertainties in the flux determination. (orig./HSI)

  11. Coherent production of single pions and ρ mesons in charged-current interactions of neutrinos and antineutrinos on neon nuclei at the Fermilab Tevatron

    International Nuclear Information System (INIS)

    The coherent production of π and ρ mesons in νμ(bar νμ)--neon charged-current interactions has been studied using the Fermilab 15-foot bubble chamber filled with a heavy Ne-H2 mix and exposed to the Teva- tron quadrupole triplet (anti)neutrino beam. The νμ (bar νμ) beam had an average energy of 80 GeV (70 GeV). From a sample corresponding to approximately 28 000 charged-current interactions, net signals of (53±9) μ±πminus-plus coherent events and (19±7) μ±πminus-plusπ0 coherent events are extracted. For E>10 GeV, the coherent pion production cross section is determined to be (3.2±0.7)x10-38 cm2 per neon nucleus whereas the coherent ρ production cross section is (2.1±0.8)x10-38 cm2 per neon nucleus. These cross sections and the kinematical characteristics of the coherent events at |t|2 are found to be in general agreement with the predictions of a model based on the hadron dominance and, in the pion case, on the partially conserved axial-vector current hypothesis. Also discussed is the coherent production of systems consisting of three pions

  12. Cross sections for neutrino and antineutrino induced pion production on hydrocarbon in the few-GeV region using MINERvA

    CERN Document Server

    McGivern, C L; Eberly, B; Aliaga, L; Altinok, O; Bellantoni, L; Bercellie, A; Betancourt, M; Bodek, A; Bravar, A; Budd, H; Cai, T; Carneiro, M F; Christy, M E; da Motta, H; Dytman, S A; Diaz, G A; Endress, E; Felix, J; Fields, L; Fine, R; Galindo, R; Gallagher, H; Golan, T; Gran, R; Harris, D A; Higuera, A; Hurtado, K; Kiveni, M; Kleykamp, J; Kordosky, M; Maher, E; Manly, S; Mann, W A; Marshall, C M; Caicedo, D A Martinez; McFarland, K S; McGowan, A M; Messerly, B; Miller, J; Mislivec, A; Morfin, J G; Mousseau, J; Naples, D; Nelson, J K; Norrick, A; Nuruzzaman,; Paolone, V; Park, J; Patrick, C E; Perdue, G N; Rakotondravohitra, L; Ramirez, M A; Ransome, R D; Ray, H; Ren, L; Rimal, D; Rodrigues, P A; Ruterbories, D; Schellman, H; Schmitz, D W; Simon, C; Salinas, C J Solano; Falero, S Sanchez; Tice, B G; Valencia, E; Walton, T; Wolcott, J; Wospakrik, M; Zhang, D

    2016-01-01

    Separate samples of charged-current pion production events representing two semi-inclusive channels nu_mu-CC(pi+) and anu_mu-CC(pi0) have been obtained using neutrino and antineutrino exposures of the MINERvA detector. Distributions in kinematic variables based upon muon-track reconstructions are analyzed and compared for the two samples. The differential cross sections for muon production angle, muon momentum, and four-momentum transfer Q2, are reported, and cross sections versus neutrino energy are obtained. Comparisons with predictions of current neutrino event generators are used to clarify the role of the Delta(1232) and higher-mass baryon resonances in CC pion production and to show the importance of pion final-state interactions. For the nu_mu-CC(pi+) (anu_mu-CC(pi0)) sample, the absolute data rate is observed to lie below (above) the predictions of some of the event generators by amounts that are typically 1-to-2 sigma. However the generators are able to reproduce the shapes of the differential cross ...

  13. 3-flavor and 4-flavor implications of the latest T2K and NOνA electron (anti-)neutrino appearance results

    Science.gov (United States)

    Palazzo, Antonio

    2016-06-01

    The two long-baseline experiments T2K and NO νA have recently presented new findings. T2K has shown the first νbare appearance data while NO νA has released the first νe appearance results. These data are of particular importance because they allow us to probe for the first time in a direct (or manifest) way the leptonic CP-violation. In fact, it is the first time that a hint of CP-violation arises from the comparison of the observations of neutrinos and antineutrinos. We consider the implications of such new results both for the standard 3-flavor framework and for the non-standard 3 + 1 scheme involving one sterile neutrino species. The 3-flavor analysis shows a consolidation of the previous trends, namely a slight preference for sin ⁡ δ statistical significance close to 90% C.L., and a mild preference (at more than 68% C.L.) for the normal hierarchy. In a 3 + 1 framework, the data constrain two CP-phases (δ13 ≡ δ and δ14), which exhibit a slight preference for the common value δ13 ≃δ14 ≃ - π / 2. Interestingly, in the enlarged four neutrino scheme the preference for the normal hierarchy found within the 3-flavor framework completely disappears. This indicates that light sterile neutrinos may constitute a potential source of fragility in the capability of the two LBL experiments of discriminating the neutrino mass hierarchy.

  14. The electron antineutrino angular correlation coefficient a in free neutron decay. Testing the standard model with the aSPECT-spectrometer

    International Nuclear Information System (INIS)

    The β-decay of free neutrons is a strongly over-determined process in the Standard Model (SM) of Particle Physics and is described by a multitude of observables. Some of those observables are sensitive to physics beyond the SM. For example, the correlation coefficients of the involved particles belong to them. The spectrometer aSPECT was designed to measure precisely the shape of the proton energy spectrum and to extract from it the electron anti-neutrino angular correlation coefficient a. A first test period (2005/2006) showed the ''proof-of-principles''. The limiting influence of uncontrollable background conditions in the spectrometer made it impossible to extract a reliable value for the coefficient a (published in 2008). A second measurement cycle (2007/2008) aimed to under-run the relative accuracy of previous experiments (δa)/(a)=5%. I performed the analysis of the data taken there which is the emphasis of this doctoral thesis. A central point are background studies. The systematic impact of background on a was reduced to (δa(syst.))/(a)=0.61 %. The statistical accuracy of the analyzed measurements is (δa(stat.))/(a)∼1.4 %. Besides, saturation effects of the detector electronics were investigated which were initially observed. These turned out not to be correctable on a sufficient level. An applicable idea how to avoid the saturation effects is discussed in the last chapter. (orig.)

  15. Measurement of the angular correlation coefficient a between electron and antineutrino in neutron β-decay with the spectrometer aSPECT

    International Nuclear Information System (INIS)

    Neutron β-decay is parametrized by several measurable correlation coefficients which are used to determine parameters of the Standard Model and to search for new physics. The aim of the retardation spectrometer aSPECT is to measure the electron-antineutrino angular correlation coefficient a with an unprecedented accuracy of well below 1%. The coefficient is extracted from a high precision measurement of the proton energy spectrum. A central point of this PhD thesis is the analysis of the background, motivated by the observations of discharges during the beam time of 2011, and an earlier indication for a dependence on the retardation potential. During this thesis, several measurements were conducted off-line, without ionizing particles from neutron decay. An 'internal' background (X-rays and ions) was identified. It has an influence of 10-5 to 10-4 on Δa/a depending on the vacuum level (∼10-9 mbar) and the spectrometer settings. Within the analysis of the data from the beam time in 2013, a model was built to correct for backgrounds present in neutron decay experiment, taking into account its time dependence. The correction is about 3% on the coefficient for standard settings and vacuum but it can reach 7% for unfavorable settings. To reduce the background, a drift electric field was applied close to the maximum of the retardation potential. Additional measurements performed during this beam time included tests of systematics, in particular the edge effect (beam profile) and different electrode settings. In order to obtain the final result, the analysis has to be extended by including the different corrections and by comparing with simulations of the systematic effects. (author)

  16. Étude du potentiel de la détection des antineutrinos pour la surveillance des réacteurs nucléaires à des fins de lutte contre la prolifération.

    OpenAIRE

    Cormon, Sandrine

    2012-01-01

    Ces dernières années, la physique des neutrinos a présenté de nouvelles perspectives de physique appliquée. En effet, les antineutrinos (ne) émis par une centrale nucléaire dépendent du combustible : leur détection constituerait donc une sonde permettant de déterminer la composition isotopique du coeur. L'Agence Internationale de l'Énergie Atomique (AIEA) a montré son intérêt pour le potentiel de cette détection comme nouvel outil au profit de son département des Garanties et a créé un groupe...

  17. Evolved Models for Elementary Particles and Atoms Require Alternating Neutrino/Antineutrino Pairs Along Interlocked or Looped Strings. Traveling Waves, TW, and Standing Waves, SW, Alternate at Nodal Notches

    Science.gov (United States)

    McLeod, Roger David; McLeod, David Matthew

    2009-05-01

    Our hydrogen atom interacts with a neutron star. Its stringy TW/SW electron is cut by a neutrino scissor that instantly becomes its end anti-node. The string has one extra neutrino in 100,000. Antimatter remains concealed. Our Dumbo Proton of a TW state is similarly cut. Inside the star, electron string/spring compresses 100,000 and 1836 times more, to proton's linear mass density. Electrostatics encourages that caboose, stringy electron, to couple with a cut proton. Linear charge densities neutralize while composite length contracts 20%. The writhing string evicts an antineutrino at closure on Pauli's authority, becoming Mickey Neutron, with looped quarks. Unstable Mickey Neutron has his ear notch forced into an ear notch of stable Dumbo Proton, achieving immortality in this deuteron marriage. Tritium is in a m'enage a trois. Alpha Nucleus has a # grid. Meta state Ne-20 predicts alpha eviction to O-16. Schr"odinger finally prevails, so string theory and Wave Mechanics can prosper.

  18. Neutrino and Antineutrino Interactions in Deuterium

    CERN Multimedia

    2002-01-01

    This experiment uses BEBC filled with deuterium and exposed to the wide-band neutrino beam N1. The use of deuterium as the target material allows to study interactions on both neutrons and protons. The charge of the target nucleon can be inferred from the number of positive and negative particles in the final state. \\\\ \\\\ Some of the physics aims of this experiment are to measure separately the cross sections @s^n and @s^p on neutrons and protons to determine the structure functions F|n(x,Q|2) and F|p(x,Q|2), the fragmentation functions D(z,Q|2) and the ratio of neutral to charged current interactions. \\\\ \\\\ Additional problems under investigation are the production of nucleon isobars, and of resonances in general, the production of strange and of charmed particles, and the problems of deuterium structure.

  19. Tests of Lorentz violation in muon antineutrino to electron antineutrino oscillations

    CERN Document Server

    Auerbach, L B; Caldwell, D O; Church, E D; Cochran, A K; Donahue, J B; Fazely, A R; Garvey, G T; Gunasingha, R M; Imlay, R L; Katori, T; Louis, W C; McIlhany, K L; Metcalf, W J; Mills, G B; Sandberg, V D; Smith, D; Stancu, I; Strossman, W H; Tayloe, R; Sung, M; Vernon, W; White, D H; Yellin, S

    2005-01-01

    A recently developed Standard-Model Extension (SME) formalism for neutrino oscillations that includes Lorentz and CPT violation is used to analyze the sidereal time variation of the neutrino event excess measured by the Liquid Scintillator Neutrino Detector (LSND) experiment. The LSND experiment, performed at Los Alamos National Laboratory, observed an excess, consistent with neutrino oscillations, of ${\\bar\

  20. Nuclear Reactor Monitoring With an Above Ground Antineutrino Detector

    Science.gov (United States)

    Classen, Timothy

    2011-04-01

    Technology to detect νe 's emitted from nuclear reactors has existed for more than 50 years. This technology has been used in a range of experiments probing the neutrino parameter space. A continuing effort has been made at LLNL to test whether this technology may be used for a more practical purpose, the monitoring of nuclear reactors with a focus on safeguarding dangerous nuclear materials. As part of this role a new detector is being developed for deployment above ground at the Point Lepreau Nuclear Generating Station in New Brunswick Canada. The detector will observe a reactor core through a full start-up phase, to determine how well it can measure changes in nuclear fuel composition. This talk will focus on the challenges of the experiment, and how the techniques of fundamental neutrino research may be used to overcome them. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  1. Recent Developments in Neutrino/Antineutrino-Nucleus Interactions

    Directory of Open Access Journals (Sweden)

    Jorge G. Morfín

    2012-01-01

    Full Text Available Recent experimental results and developments in the theoretical treatment of neutrino-nucleus interactions in the energy range of 1–10 GeV are discussed. Difficulties in extracting neutrino-nucleon cross sections from neutrino-nucleus scattering data are explained and significance of understanding nuclear effects for neutrino oscillation experiments is stressed. Detailed discussions of the status of two-body current contribution in the kinematic region dominated by quasielastic scattering and specific features of partonic nuclear effects in weak DIS scattering are presented.

  2. Theoretical Antineutrino Detection, Direction and Ranging at Long Distances

    CERN Document Server

    Jocher, G R; Dobbs, B M; Dye, S T; Learned, J A Georges III J G; Mulliss, C L; Usman, S

    2013-01-01

    In this paper we introduce the concept of what we call "NUDAR" (NeUtrino Direction and Ranging), making the point that measurements of the observed energy and direction vectors can be employed to passively deduce the exact three-dimensional location and thermal power of geophysical and anthropogenic neutrino sources from even a single detector. We present the most precise background estimates to date, all handled in full three dimensions, as functions of depth and geographical location. For the present calculations, we consider a hypothetical 138 kiloton detector which can be transported to an ocean site and deployed to an operational depth. We present a Bayesian estimation framework to incorporate any a priori knowledge of the reactor that we are trying to detect, as well as the estimated uncertainty in the background and the oscillation parameters. Most importantly, we fully employ the knowledge of the reactor spectrum and the distance-dependent effects of neutrino oscillations on such spectra. The latter, ...

  3. Computer-aided design and construction of an antineutrino detector

    International Nuclear Information System (INIS)

    The Bugey group is setting-up a new detector for another neutrino oscillation experiment. This thesis reports on the different steps concerning its realisation. Light yield, light transmission and pulse shape discrimination properties of NE 320 a new liquid scintillator loaded with 0.15% of Lithium 6 allow to realise a large volume detector (3 x 600 l) with an order of magnitude increase in sensitivity. The benefit of the neutron capture on Lithium 6 has been conserved owing to the segmentation of the whole detector volume in 98 cells and to energy resolution and pulse shape discrimination properties of the liquid. The efficiency is expected to be 0.5 and the essential component of the background is the natural activity of the scintillator. This makes this detector the most performant for neutrino oscillation experiment at reactor

  4. Study of charmed-quark production by antineutrinos

    International Nuclear Information System (INIS)

    This Letter presents the x and y distributions of events with visible strange particles produced in charged-current nu-barp interactions. It is shown that charmed-particle production via the process nu-bar/sub μ/s-bar→μ+c-bar is required. Using a simple model, we obtain, for the proton, ∫xs-bar(x)dx=0.007 +- 0.002 and ∫xs-bar(x)dx/∫xu(x)dx=0.019 +- 0.006 in the kinematic region 0.05< x< or =0.8 and 0.1< y< or =0.8. Moreover, these observations require a significant left-handed component for the (/sup c//sub s/) doublet

  5. Azimuthal asymmetry of hadrons produced in antineutrino reactions

    International Nuclear Information System (INIS)

    Preliminary results on an azimuthal asymmetry of the hadrons about the current direction in ν-barNe interactions for π- distributions are reported. The distributions of γ show a bremstrahlung effect from the muon. (author)

  6. Dimuon events produced in high energy antineutrino interactions observed in BEBC

    International Nuclear Information System (INIS)

    A study is presented of dimuon events from an exposure of BEBC to a wide band anti ν beam from the CERN SPS. These data double the available statistics on anti ν induced dilepton events observed in bubble chambers. The relative production rate and V0 yield have been measured and found to agree with previous experiments. The analysis of several kinematical variables shows that the gros features of the data agree with the predictions of the GIM model. Some indication exists that part of the signal could be due to quasi elastic production of the 'beautiful baryon', but the statistical significance is too weak to draw definitive conclusions. (orig.)

  7. Determination of the neutral to charged current cross-section ratio for antineutrino interactions on protons

    International Nuclear Information System (INIS)

    An exposure of BEBC equipped with the hydrogen-filled TST to the anti νsub(μ) wide band beam at the CERN SPS has been used to study anti νsub(μ) interactions on free protons. About 700 neutral induced interactions on free protons. About 700 neutral induced interactions have been observed inside the hydrogen and separated into charged current, neutral current and neutral hadron interactions using a multivariate discriminant analysis based on the kinematics of the events. The neutral to charged current cross-section ratio has been determined to be Rsub(p)anti ν = 0.33 +- 0.04. When combined with the value of Rsub(p)sup(ν) previously determined in the same experiment, the result is compatible with the prediction of the standard SU(2) X U(1) model for sin2thetasub(W) = 0.24sub(-0.08)sup(+0.06) and rho = 1.07sub(-0.08)sup(+0.06). Fixing the parameter rho = 1 yields sin2thetasub(W) = 0.18 +- 0.04. (orig.)

  8. Determination of the neutral to charged current cross-section ratio for antineutrino interactions on protons

    Science.gov (United States)

    Moreels, J.; Van Doninck, W.; Alamatsaz, H.; Armenise, N.; Azemoon, T.; Bartley, J. H.; Baton, J. P.; Belusevic, R.; Bertrand, D.; Brisson, V.; Calicchio, M.; Colley, D. C.; Cooper, A. M.; Erriquez, O.; Fogli-muciaccia, M. T.; Gerbier, G.; Guy, J. G.; Jones, G. T.; Kochowski, C.; Michette, A. G.; Natali, S.; Neveu, M.; Nuzzo, S.; O'Neale, S.; Parker, M. A.; Petiau, P.; Ruggieri, F.; Sacton, J.; Sewell, S.; Tyndel, M.; Vander Velde, G.; Venus, W.; Vortuba, M. F.; BEBC TST Neutrino Collaboration

    1984-04-01

    An exposure of BEBC equipped with the hydrogen-filled TST to the overlinevμ wide band beam at the CERN SPS has been used to study overlinevμ interactions on free protons. About neutral induced interactions have been observed inside the hydrogen and separated into charged current, neutral current and neutral hadron interactions using a multivariate discriminant analysis based on the kinematics of the events. The neutral to charged current cross-section ratio has been determined to be R poverlinev = 0.33 ± 0.04 . When combined with the value of Rpv previously determined in the same experiment, the result is compatible with the prediction of the standard SU (2) × U (1) model for sin 2θW = 0.24 -0.08+0.06 and ρ = 1.07 -0.08+0.06. Fixing the parameter ρ = 1 yields sin 2θW = 0.18 ± 0.04.

  9. Dimuon events produced in high energy antineutrino interactions observed in BEBC

    Science.gov (United States)

    Armenise, N.; Calicchio, M.; Erriquez, O.; Fogli-Muciaccia, M. T.; Natali, S.; Nuzzo, S.; Romano, F.; Belusevic, R.; Colley, D. C.; Jones, G. T.; Lowe, L.; O'Neale, S.; Sewell, S. J.; Votruba, M. F.; Bertrand, D.; Sacton, J.; Vander Velde-Wilquet, C.; Van Doninck, W.; Wilquet, G.; Brisson, V.; Francois, T.; Kluberg, L.; Petiau, P.; Cooper, A. M.; Guy, J. G.; Michette, A. G.; Tyndel, M.; Venus, W.; Gerbier, G.; Alitti, J.; Baton, J. P.; Iori, M.; Kochowski, C.; Neveu, M.; Baker, N. J.; Bartley, J. H.; BEBC “TST” Neutrino Collaboration

    1980-08-01

    A study is presented of dimuon events from an exposure of BEBC to a wide band overlineν beam from the CERN SPS. These data double the available statistics on overlineν induced dilepton events observed in bubble chambers. The relative production rate and V 0 yield have been measured and found to agree with previous experiments. The analysis of several kinematical variables shows that the gros features of the data agree with the predictions of the GIM model. Some indication exists that part of the signal could be due to quasi elastic production of the “beautiful baryon”, but the statistical significance is too weak to draw definitive conclusions.

  10. Total cross section of neutrino(antineutrino) radiative scattering on deuteron with accounting of neutrino spectra

    International Nuclear Information System (INIS)

    The analytical expression of total cross section σγ of the process γ(anti γ)+d → ν(anti ν)+d+γ, where ν=νsub(e), νsub(μ) or νsub(tau) is obtained. Cross section averaging over the spectrum of reactor anti νsub(e) is performed. A possibility of recording the investigated process is discussed. Numerical estimations of delta sub(γ) cross section in the Glashow-salam-Weinbera (GSW) model for reactor anti ν flow fsub(anti ν) approximately 8x1013 anti νsub(e)/cmsup(2)xs are performed. The form of reactor anti νsub(e) spectrum is taken into account. The numerical estimation results are presented in the graphical form. The σ sub(γ) value at minimum energy of the detected photon ωsub(min)=0.5 MeV in the GSM model constitutes approximately 0.63x10-19 cm2, which taking into account the detector weight of 10 t provides about 485 events per year

  11. Study of muon neutrino and muon antineutrino disappearance with the NOvA neutrino oscillation experiment

    Energy Technology Data Exchange (ETDEWEB)

    Pawloski, Gregory [Univ. of Minnesota, Minneapolis, MN (United States)

    2014-06-30

    The primary goal of this working group is to study the disappearance rate of νμ charged current events in order to measure the mixing angle θ23 and the magnitude of the neutrino mass square splitting Δm 232.

  12. Monte-Carlo simulations on the antineutrino detection in heavy ion collisions

    International Nuclear Information System (INIS)

    Aim of the present thesis was to study, how far a large-area neutron detector with high efficiency operated at the Corporation for Heavy Ion Research in Darmstadt can also by applied for experiments on the sub-threshold antineutron production in heavy ion reactions for the study of the equation of state of highly excited nuclear matter. The experimental part consisted in the partition at the construction, the taking into operation, and the calibration measurements of the target-detector system, as well at the experiments with the LAND detector for the study of the Coulomb excitation of 136Xe projectiles in the reaction 136Xe+208Pb at 700 respectively 800 MeV/u. Studies on the suppression of neutron events against antineutron events in the data acquisition in a typical SIS/LAND experiment on the antineutron production in heavy ion collisions were performed. The possibilities available on the level of the hardware trigger for the suppression of (multiple) neutron events were studied. Thereby resulted a reachable suppression factor of ≅ 10-3. Studies on the off-line analysis of antineutron events exhibited problems, which base on the high matter density in the detector. (orig./HSI)

  13. Study of the neutral current properties in the semileptonic inclusive neutrino and antineutrino nucleon interaction

    International Nuclear Information System (INIS)

    In the dechromatic neutron beam of the CERN-SPS results obtained with the CHARM detector from the deep inelastic inclusive neutrino-nucleon scattering were analyzed according to following reactions: #betta#sub(μ)(anti #betta#sub(μ))+N->μ-(μ+) + hadrons and #betta#sub(μ)(anti #betta#sub(μ))+N->#betta#sub(μ)(anti #betta#sub(μ)) + hadrons. The aim of these studies was the determination of the coupling of neutral currents in the weak interaction. All data can be well described by the standard model for the unification of the electrogmagnetic and weak interaction in connection with the quarkparton model, if a Weinberg angle of sin2deltasub(w)=0.222+-0.016 is assumed. (orig./HSI)

  14. Single photon production induced by (anti)neutrino neutral current scattering on nucleons and nuclear targets

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez-Ruso, L.; Nieves, J. [Instituto de Física Corpuscular (IFIC), Centro Mixto CSIC-Universidad de Valencia, Institutos de Investigación de Paterna, E-46071 Valencia (Spain); Wang, E. [Instituto de Física Corpuscular (IFIC), Centro Mixto CSIC-Universidad de Valencia, Institutos de Investigación de Paterna, E-46071 Valencia (Spain); Department of Physics, Zhengzhou University, Zhengzhou, Henan 450001 (China)

    2015-10-15

    We review our theoretical approach to neutral current photon emission on nucleons and nuclei in the few-GeV energy region, relevant for neutrino oscillation experiments. These reactions are dominated by the weak excitation of the Δ(1232) resonance but there are also important non-resonant contributions. We have also included terms mediated by nucleon excitations from the second resonance region. On nuclei, Pauli blocking, Fermi motion and the in-medium Δ resonance broadening have been taken into account for both incoherent and coherent reaction channels. With this model, the number and distributions of photon events at the MiniBooNE and T2K experiments have been obtained. We have also compared to the NOMAD upper limit at higher energies. The implications of our findings and future perspectives are discussed.

  15. Discovery of the τ lepton and electron antineutrino awarded the 1995 Nobel Physics Prize

    International Nuclear Information System (INIS)

    American physicists Martin Perl and Fredrick Reines shared the 1995 Nobel Prize for physics for the discoveries of two of nature's most remarkable subatomic particles. Their pioneering contributions in lepton physics under-pinned subsequent developments in establishing the present picture of matter at the lepton-quark level

  16. Neutral strange particle production in neutrino and antineutrino charged-current interactions on neon

    International Nuclear Information System (INIS)

    A study has been made of neutral strange particle production in νμNe and bar νμNe charged-current interactions at a higher energy than any previous study. The experiment was done at the Fermilab Tevatron using the 15-ft. bubble chamber, and the data sample consists of 814(154) observed neutral strange particles from 6263(1115) ν(bar ν) charged-current events. For the ν beam (average event energy left-angle Eν right-angle=150 GeV), the average multiplicities per charged-current event have been measured to be 0.408±0.048 for K0, 0.127±0.014 for Λ, and 0.015±0.005 for bar Λ, which are significantly greater than for lower-energy experiments. The dependence of rates on kinematical variables has been measured, and shows that both K0 and Λ production increase strongly with Eν, W2, Q2, and yB. Compared to lower-energy experiments, single-particle distributions indicate that there is much more K0 production for xF>-0.2, and the enhanced Λ production spans most of the kinematic region. bar Λ production is mostly in the region |xF|F>-0.2 there is a significant excess of Λ production over the model's prediction. The Λ hyperons are found to be polarized in the production plane

  17. Relativistic model of 2p-2h meson exchange currents in (anti)neutrino scattering

    CERN Document Server

    Simo, I Ruiz; Barbaro, M B; De Pace, A; Caballero, J A; Donnelly, T W

    2016-01-01

    We develop a model of relativistic, charged meson-exchange currents (MEC) for neutrino-nucleus interactions. The two-body current is the sum of seagull, pion-in-flight, pion-pole and $\\Delta$-pole operators. These operators are obtained from the weak pion-production amplitudes for the nucleon derived in the non-linear $\\sigma$-model together with weak excitation of the $\\Delta(1232)$ resonance and its subsequent decay into $N\\pi$. With these currents we compute the five 2p-2h response functions contributing to $(\

  18. Comparative investigation of spin asymmetry in elastic neutrino-, antineutrino- and electro-proton scattering

    International Nuclear Information System (INIS)

    Various spin asymmetries in the processes of the ν(ν-tilde)p- and eL,p-p-elastic scattering on the polarized and nonpolarized proton target are studied with an account of the weak and electromagnetic form factors of the GEp, GMp and gVp, gAp proton, including the gAp(s) isoscalar axial-vector and fVp neutral weak magnetic contributions. It is shown that comparative studies on these asymmetries in dependence on the energy of the incident lepton and yield proton may present valuable information on the strange quark content αs|p> and αγ5s|p> of the proton magnetic moment

  19. Experimental study of invariance violations in neutrino and antineutrino reactions at high energy

    International Nuclear Information System (INIS)

    This work is dedicated to the study of the structure functions in neutrino-nucleon interactions and to the interpretation of observed violations of scaling invariance. The first chapter describes the experimental setting, the Cargamelle cloud chamber has been used. The second chapter presents the data analysis, the event selection methodology, the muon identification and the energy correction that takes into account the non-detected particles. We also present the bi-dimensional x and q2 distribution of events that is necessary to the determination of the structure functions. In the third chapter we detail the theoretical basis of our analysis: we define relevant kinematic variables and we discuss the scale invariance in the light of the quark-parton model. The violations of the scale invariance are considered first in the formalism of quantum chromodynamics and then in the view of higher twist or mass corrections. The fourth chapter deals with the experimental determination of the structure functions and of the violations of the scaling invariance. (A.C.)

  20. One meson π0 final state study in neutral current neutrino and antineutrino interactions

    International Nuclear Information System (INIS)

    Neutral pion production by weak neutral currents was observed in the CERN-GARGAMELLE neutrino experiment. The aim of the analysis was the measurement of the ratios R(ν) and R(antiν) of neutral-current to charged-current cross sections. The background due to neutron interactions was computed. A lower and an upper limit of the background was obtained. Bounds on the ratios R(ν) and R(antiν) are given using these limits: 0.11< R(ν)<0.22; 0.16< R(antiν)<0.52. Theoretical predictions for R(ν) were obtained in the framework of the Weinberg-Salam model. It is not possible to compare the experimental result with these theoretical evaluation because of nuclear corrections

  1. Single photon production induced by (anti)neutrino neutral current scattering on nucleons and nuclear targets

    International Nuclear Information System (INIS)

    We review our theoretical approach to neutral current photon emission on nucleons and nuclei in the few-GeV energy region, relevant for neutrino oscillation experiments. These reactions are dominated by the weak excitation of the Δ(1232) resonance but there are also important non-resonant contributions. We have also included terms mediated by nucleon excitations from the second resonance region. On nuclei, Pauli blocking, Fermi motion and the in-medium Δ resonance broadening have been taken into account for both incoherent and coherent reaction channels. With this model, the number and distributions of photon events at the MiniBooNE and T2K experiments have been obtained. We have also compared to the NOMAD upper limit at higher energies. The implications of our findings and future perspectives are discussed

  2. DANSS: Detector of the reactor AntiNeutrino based on Solid Scintillator

    CERN Document Server

    Alekseev, I; Brudanin, V; Danilov, M; Egorov, V; Filosofov, D; Fomina, M; Hons, Z; Kazartsev, S; Kobyakin, A; Kuznetsov, A; Machikhiliyan, I; Medvedev, D; Nesterov, V; Olshevsky, A; Ponomarev, D; Rozova, I; Rumyantseva, N; Rusinov, V; Salamatin, A; Shevchik, Ye; Shirchenko, M; Shitov, Yu; Skrobova, N; Starostin, A; Svirida, D; Tarkovsky, E; Tikhomirov, I; Vlasek, J; Zhitnikov, I; Zinatulina, D

    2016-01-01

    The DANSS project is aimed at creating a relatively compact neutrino spectrometer which does not contain any flammable or other dangerous liquids and may therefore be located very close to the core of an industrial power reactor. As a result, it is expected that high neutrino flux would provide about 15,000 IBD interactions per day in the detector with a sensitive volume of 1 m$^3$. High segmentation of the plastic scintillator will allow to suppress a background down to a 1% level. Numerous tests performed with a simplified pilot prototype DANSSino under a 3 GW$_{th}$ reactor of the Kalinin NPP have demonstrated operability of the chosen design. The DANSS detector surrounded with a composite shield is movable by means of a special lifting gear, varying the distance to the reactor core in a range from 10 m to 12 m. Due to this feature, it could be used not only for the reactor monitoring, but also for fundamental research including short-range neutrino oscillations to the sterile state. Supposing one-year mea...

  3. A search for muon neutrino and antineutrino disappearance in the Booster Neutrino Beam

    Energy Technology Data Exchange (ETDEWEB)

    Mahn, Kendall Brianna McConnel; /Columbia U.

    2009-04-01

    This dissertation presents a search for {mu}{sub {nu}} and {bar {mu}{sub {nu}}} disappearance with the MiniBooNE experiment in the {Delta}m{sup 2} region of a few eV{sup 2}. Disappearance measurements in this oscillation region constrain sterile neutrino models and CPT violation in the lepton sector. Fits to the shape of the {mu}{sub {nu}} and {bar {mu}{sub {nu}}} energy spectra reveal no evidence for disappearance in either mode. This is the first test of {bar {mu}{sub {nu}}} disappearance between {Delta}m{sup 2} = 0:1 -- 10 eV2. In addition, prospects for performing a joint analysis using the SciBooNE detector in conjunction with MiniBooNE are discussed.

  4. Untersuchung der Eigenschaften neutraler Stroeme in der semileptonischen inklusiven Neutrino und Antineutrino Nukleon Wechselwirkung

    CERN Document Server

    Kroger, Bernd

    1981-01-01

    In the dechromatic neutron beam of the CERN-SPS results obtained with the CHARM detector from the deep inelastic inclusive neutrino-nucleon scattering were analyzed according to following reactions: #betta#sub(μ)(anti #betta#sub(μ))+N->μ-(μ+) + hadrons and #betta#sub(μ)(anti #betta#sub(μ))+N->#betta#sub(μ)(anti #betta#sub(μ)) + hadrons. The aim of these studies was the determination of the coupling of neutral currents in the weak interaction. All data can be well described by the standard model for the unification of the electrogmagnetic and weak interaction in connection with the quarkparton model, if a Weinberg angle of sin2deltasub(w)=0.222+-0.016 is assumed. (orig./HSI)

  5. Search for Muon Neutrino and Antineutrino Disappearance in MiniBooNE

    International Nuclear Information System (INIS)

    The MiniBooNE Collaboration reports a search for νμ and νμ disappearance in the Δm2 region of 0.5-40 eV2. These measurements are important for constraining models with extra types of neutrinos, extra dimensions, and CPT violation. Fits to the shape of the νμ and νμ energy spectra reveal no evidence for disappearance at the 90% confidence level (C.L.) in either mode. The test of νμ disappearance probes a region below Δm2=40 eV2 never explored before.

  6. Charged-current neutrino and antineutrino scattering off Cd-116 described by Skyrme forces

    Czech Academy of Sciences Publication Activity Database

    Almosly, W.; Carlsson, B. G.; Dobaczewski, J.; Suhonen, J.; Toivanen, J.; Veselý, Petr; Ydrefors, E.

    2014-01-01

    Roč. 89, č. 2 (2014), 024308. ISSN 0556-2813 Institutional support: RVO:61389005 Keywords : double-beta decay * nuclear structure Subject RIV: BE - Theoretical Physics Impact factor: 3.733, year: 2014

  7. Background for Terrestrial Antineutrino Investigations: Radionuclide Distribution, Georeactor Fission Events, and Boundary Conditions on Fission Power Production

    OpenAIRE

    Herndon, J. Marvin; Edgerley, Dennis A.

    2005-01-01

    Estimated masses of fissioning and non-fissioning radioactive elements and their respective distributions within the Earth are presented, based upon the fundamental identity of the components of the interior 82% of the Earth, the endo-Earth, with corresponding components of the Abee enstatite chondrite meteorite. Within limits of existing data, the following generalizations concerning the endo-Earth radionuclides can be made: (1) Most of the K-40 may be expected to exist in combination with o...

  8. Measurement of the electron-antineutrino angular correlation coefficient a in neutron beta decay with the spectrometer aSPECT

    Energy Technology Data Exchange (ETDEWEB)

    Petzoldt, G.

    2007-08-29

    In the four beam times we performed at the FRM-II, we were able to show that the spectrometer works in principle and that a determination of a with it is possible. A set of routines has been written for decoding and analyzing the raw data. The routines are written in C using the ROOT libraries and can be easily adapted or expanded. We have found a reliable way to extract the proton count rates from the data by building pulseheight spectra for each measurement, subtracting background measurements from those and fitting the resulting peak with a Gaussian. The background of the measurements was studied in detail. The background caused by electrons from neutron decay is very well understood and conforms quantitatively to our expectation. Due to the spatial resolution of our detector and the time resolution provided by our DAQ electronics, we were able to study correlated electron-proton pairs from one neutron decay event. They form a clearly visible peak in a time- and channel-distance spectrum, which can be shifted in the channel-dimension by varying the voltages applied to the lower and upper E x B electrodes. Performing a pulseheight analysis for both involved particles allowed us to obtain a fairly clean energy spectrum of the background caused by electrons from neutron decay in our detector. Using these correlations for data analysis may be of interest for future neutron decay experiments which use segmented detectors. (orig.)

  9. Measurement of the electron-antineutrino angular correlation coefficient a in neutron beta decay with the spectrometer aSPECT

    International Nuclear Information System (INIS)

    In the four beam times we performed at the FRM-II, we were able to show that the spectrometer works in principle and that a determination of a with it is possible. A set of routines has been written for decoding and analyzing the raw data. The routines are written in C using the ROOT libraries and can be easily adapted or expanded. We have found a reliable way to extract the proton count rates from the data by building pulseheight spectra for each measurement, subtracting background measurements from those and fitting the resulting peak with a Gaussian. The background of the measurements was studied in detail. The background caused by electrons from neutron decay is very well understood and conforms quantitatively to our expectation. Due to the spatial resolution of our detector and the time resolution provided by our DAQ electronics, we were able to study correlated electron-proton pairs from one neutron decay event. They form a clearly visible peak in a time- and channel-distance spectrum, which can be shifted in the channel-dimension by varying the voltages applied to the lower and upper E x B electrodes. Performing a pulseheight analysis for both involved particles allowed us to obtain a fairly clean energy spectrum of the background caused by electrons from neutron decay in our detector. Using these correlations for data analysis may be of interest for future neutron decay experiments which use segmented detectors. (orig.)

  10. 6Li-loaded directionally sensitive anti-neutrino detector for possible geo-neutrinographic imaging applications

    Science.gov (United States)

    Tanaka, H. K. M.; Watanabe, H.

    2014-04-01

    Despite the latent and unique benefits of imaging uranium and thorium's distribution in the earth's interior, previously proposed experimental techniques used to identify the incoming geo-neutrino's direction are not applicable to practical imaging due to the high miss-identification in a neutrino's track reconstruction. After performing experimental studies and Monte-Carlo simulations, we confirmed that a significant improvement is possible in neutrino tracking identification with a 6Li-loaded neutrino detector. For possible imaging applications, we also explore the feasibility of producing geo-neutrinographic images of gigantic magmatic reservoirs and deep structure in the mantle. We anticipate and plan to apply these newly designed detectors to radiographic imaging of the Earth's interior, monitoring of nuclear reactors, and tracking astrophysical sources of neutrinos.

  11. Background for Terrestrial Antineutrino Investigations: Radionuclide Distribution, Georeactor Fission Events, and Boundary Conditions on Fission Power Production

    CERN Document Server

    Herndon, J M; Edgerley, Dennis A.

    2005-01-01

    Estimated masses of fissioning and non-fissioning radioactive elements and their respective distributions within the Earth are presented, based upon the fundamental identity of the components of the interior 82% of the Earth, the endo-Earth, with corresponding components of the Abee enstatite chondrite meteorite. Within limits of existing data, the following generalizations concerning the endo-Earth radionuclides can be made: (1) Most of the K-40 may be expected to exist in combination with oxygen in the silicates of the lower mantle, perhaps being confined to the upper region of the lower mantle where it transitions to the upper mantle; (2) Uranium may be expected to exist at the center of the Earth where it may undergo self-sustaining nuclear fission chain reactions, but there is a possibility that some non-fissioning uranium may be found scattered diffusely within the core floaters which are composed of CaS and MgS; and, (3) Thorium may be expected to occur within the core floaters at the core-mantle bound...

  12. Measurement of the electron antineutrino angular correlation coefficient a with the neutron decay spectrometer aSPECT

    Energy Technology Data Exchange (ETDEWEB)

    Simson, Martin

    2010-09-21

    This thesis describes measurements with the retardation spectrometer aSPECT at the Institut Laue-Langevin in Grenoble. The goal of the measurement is to determine the angular correlation coefficient a from the form of the proton recoil spectrum in the decay of the free neutron in order to determine a precise value for the ratio of the weak axial vector and vector coupling constants of the nucleon. A big improvement was achieved with the use of a silicon drift detector which was used here for the first time to detect low energetic protons. A saturation effect of the electronics that was only discovered during the analysis of the data from neutron decay proved to be not correctable. The findings from analysis, simulations and test experiments gained in this work should allow a measurement of a with high precision in a future beamtime. (orig.)

  13. Performances and stability of a 2.4 ton Gd organic liquid scintillator target for antineutrino detection

    CERN Document Server

    Barabanov, I R; Cattadori, C; Danilov, N A; Di Vacri, A; Krilov, Yu S; Ioannucci, L; Yanovich, E A; Aglietta, M; Bonardi, A; Bruno, G; Fulgione, W; Kemp, E; Malguin, A S; Porta, A; Selvi, M

    2008-01-01

    In this work we report the performances and the chemical and physical properties of a (2 x 1.2) ton organic liquid scintillator target doped with Gd up to ~0.1%, and the results of a 2 year long stability survey. In particular we have monitored the amount of both Gd and primary fluor actually in solution, the optical and fluorescent properties of the Gd-doped liquid scintillator (GdLS) and its performances as a neutron detector, namely neutron capture efficiency and average capture time. The experimental survey is ongoing, the target being continuously monitored. After two years from the doping time the performances of the Gd-doped liquid scintillator do not show any hint of degradation and instability; this conclusion comes both from the laboratory measurements and from the "in-tank" measurements. This is the largest stable Gd-doped organic liquid scintillator target ever produced and continuously operated for a long period.

  14. Measurement of the electron antineutrino angular correlation coefficient a with the neutron decay spectrometer aSPECT

    International Nuclear Information System (INIS)

    This thesis describes measurements with the retardation spectrometer aSPECT at the Institut Laue-Langevin in Grenoble. The goal of the measurement is to determine the angular correlation coefficient a from the form of the proton recoil spectrum in the decay of the free neutron in order to determine a precise value for the ratio of the weak axial vector and vector coupling constants of the nucleon. A big improvement was achieved with the use of a silicon drift detector which was used here for the first time to detect low energetic protons. A saturation effect of the electronics that was only discovered during the analysis of the data from neutron decay proved to be not correctable. The findings from analysis, simulations and test experiments gained in this work should allow a measurement of a with high precision in a future beamtime. (orig.)

  15. Production of W+ with an anomalous magnetic moment via the collision of an ultrahigh-energy (antineutrino on a target nucleon

    Directory of Open Access Journals (Sweden)

    R. M. García-Hidalgo

    2005-01-01

    Full Text Available Se discute la producción de bosones WŦ en procesos de dispersión muy inelásticos (VlVl + N → lŦ + WŦ + X (N: P protón, N neutrón, en el contexto de un modelos electrodebil, en el cual las autointeracciones bosónicas pueden ser diferentes de las prescritas por el modelo estándar de la interacción electrodebil. Se presentan resultados que muestran las fuerte dependencia de la sección transeversal en el momento dipolar magnético anómalo • del W§. Se muestra que inclusive pequeñas desviaciones del valor del modelo estándar k(k = 1 podrían implicar grandes desviaciones en el valor de la sección transversal de la producción de bosones WŦ a través de la colisión de un (anti neutrino ultraenergético sobre un nucleón blanco. Sin embargo, el incremento de los valores de la sección transversal no es suficientemente grande para ser detectable.

  16. Study of the k+ to pi+, neutrino, anti-neutrino decay in the momentum region p(pi+) < 199 MeV/C

    Energy Technology Data Exchange (ETDEWEB)

    Artamonov, A.V.; Bassalleck, B.; Bhuyan, B.; Blackmore, E.W.; Bryman, D.A.; Chen, S.; Chiang, I.-H.; Christidi, I.-A.; Cooper, P.S.; Diwan, M.V.; Frank, J.S.; /Serpukhov, IHEP /New Mexico U. /Brookhaven /TRIUMF /British Columbia U. /Tsinghua U., Beijing /SUNY, Stony Brook /Fermilab /Kyoto U. /KEK, Tsukuba /Moscow, INR

    2009-01-01

    Experiment E949 at Brookhaven National Laboratory has observed three candidate events for the decay K{sup +} {yields} {pi}{sup +}{nu}{bar {nu}} in the pion momentum region 140 < P{sub {pi}} < 199 MeV/c in a exposure of 1.71 x 10{sup 12} stopped kaons with an estimated total background of 0.93 {+-} 0.17(stat.){sub -0.24}{sup +0.32}(syst.) events. Combination of this observation with previous results, assuming a pion spectrum as predicted by the standard model, produces a branching fraction of {beta} = (1.73{sub -1.05}{sup +1.15}) x 10{sup -10}. We also give the interpretation of the combined results for alternative model of the decay K{sup +} {yields} {pi}{sup +} + nothing.

  17. Low-energy (anti)neutrino physics with Borexino: Neutrinos from the primary proton-proton fusion process in the Sun

    CERN Document Server

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

    2015-01-01

    The Sun is fueled by a series of nuclear reactions that produce the energy that makes it shine. The primary reaction is the fusion of two protons into a deuteron, a positron and a neutrino. These neutrinos constitute the vast majority of neutrinos reaching Earth, providing us with key information about what goes on at the core of our star. Several experiments have now confirmed the observation of neutrino oscillations by detecting neutrinos from secondary nuclear processes in the Sun; this is the first direct spectral measurement of the neutrinos from the keystone proton-proton fusion. This observation is a crucial step towards the completion of the spectroscopy of pp-chain neutrinos, as well as further validation of the LMA-MSW model of neutrino oscillations.

  18. JUNO: a General Purpose Experiment for Neutrino Physics

    CERN Document Server

    Grassi, Marco

    2016-01-01

    JUNO is a 20 kt Liquid Scintillator Antineutrino Detector currently under construction in the south of China. This report reviews JUNO's physics programme related to all neutrino sources but reactor antineutrinos, namely neutrinos from supernova burst, solar neutrinos and geoneutrinos.

  19. Earthquake Forecast via Neutrino Tomography

    OpenAIRE

    Wang, Bin(Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, China); Chen, Ya-Zheng; Li, Xue-Qian

    2010-01-01

    We discuss the possibility of forecasting earthquakes by means of (anti)neutrino tomography. Antineutrinos emitted from reactors are used as a probe. As the antineutrinos traverse through a region prone to earthquakes, observable variations in the matter effect on the antineutrino oscillation would provide a tomography of the vicinity of the region. In this preliminary work, we adopt a simplified model for the geometrical profile and matter density in a fault zone. We calculate the survival p...

  20. Production of events with two or three muons in the final state during the interaction on nucleons of neutrinos and anti-neutrinos of the CERN narrow band beam with a maximum energy of 200 GeV

    International Nuclear Information System (INIS)

    A study was made of the production of dimuons and trimuons in the neutrino interactions using the data of the CDHS (CERN-Dortmund-Heidelberg-Saclay Cooperation) experiment taken in the CERN narrow band beam. The analysis of the quick results (since the statistics are weak) leads to significant conclusions on these events: 1) the c quark fragmentation function is approximately flat, 2) the production of heavy leptons, if this exists, only represents a very small part of the charged currents (10-4 approximately). 3) the pair production of charmed quarks can explain some of the dimuons of same sign, the greater part of these events coming from the semi leptonic disintegration of pions and kaons (π→μν,K → μν) produced in the hadronic jet. 4) any other process (for instance the production of b quarks) is very weak (-3 of the charged currents)

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

    CERN Document Server

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

    2012-01-01

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

  2. Results and Prospects from T2K

    CERN Document Server

    Duffy, Kirsty

    2016-01-01

    As measurements of the neutrino oscillation parameters improve it is becoming more interesting to study antineutrino oscillations, to investigate CP and CPT violation in the lepton sector and nonstandard matter effects. We present the most recent T2K antineutrino oscillation results, from data collected using a muon antineutrino-enhanced neutrino beam corresponding to 4.01E20 protons on target. The first analysis of electron antineutrino appearance at T2K is presented, as well as world-leading measurements of the dominant oscillation parameters for muon antineutrino disappearance. T2K measures $\\sin^2(\\bar{\\theta}_{23}) = 0.46^{+0.14}_{-0.06}$ and $\\Delta \\bar{m}^2_{32} = 2.50^{+0.3}_{-0.2} \\times 10^{-3} \\mbox{eV}^2$, which is consistent with previous T2K measurements of the neutrino oscillation parameters and existing antineutrino measurements.

  3. Neutrinos and Energetics of the Earth

    OpenAIRE

    Fiorentini, G.; Mantovani, F.; Ricci, B.

    2002-01-01

    We estimate terrestrial antineutrino and neutrino fluxes according to different models of Earth composition. We find large variations, corresponding to uncertainties on the estimated $U$, $Th$ and $K$ abundances in the mantle. Information on the mantle composition can be derived from antineutrino flux measurements after subtracting the crust contribution. This requires a good description of the crust composition in the region of the detector site. Measurements of terrestrial antineutrinos wil...

  4. A Search for Nucleon Decay via $n \\rightarrow \\bar{\

    OpenAIRE

    Collaboration, Super-Kamiokande; :; Abe, K.; Hayato, Y.; Iida, T; Iyogi, K.; Kameda, J.; Koshio, Y.; Kozuma, Y.; Marti, Ll.; Miura, M.; Moriyama, S.; Nakahata, M.(University of Tokyo, Institute for Cosmic Ray Research, Kamioka Observatory, Kamioka, Japan); Nakayama, S.; Obayashi, Y.

    2013-01-01

    We present the results of searches for nucleon decay via bound neutron to antineutrino plus pizero and proton to antineutrino plus piplus using data from a combined 172.8 kiloton-years exposure of Super-Kamiokande-I, -II, and -III. We set lower limits on the partial lifetime for each of these modes. For antineutrino pizero, the partial lifetime is >1.1x10^{33} years; for antineutrino piplus, the partial lifetime is >3.9x10^{32} years at 90% confidence level.

  5. Single neutral pion production by charged-current $\\bar{\

    CERN Document Server

    Aliaga, L; Bercellie, A; Bodek, A; Bravar, A; Brooks, W K; Butkevich, A; Caicedo, D A Martinez; Carneiro, M F; Christy, M E; Chvojka, J; da Motta, H; Devan, J; Dytman, S A; Díaz, G A; Eberly, B; Felix, J; Fields, L; Fine, R; Gago, A M; Gallagher, H; Gran, R; Harris, D A; Higuera, A; Hurtado, K; Kordosky, M; Le, T; Maher, E; Manly, S; Mann, W A; Marshall, C M; McFarland, K S; McGivern, C L; McGowan, A M; Miller, J; Morfín, J G; Mousseau, J; Nelson, J K; Norrick, A; Osta, J; Palomino, J L; Paolone, V; Park, J; Patrick, C E; Perdue, G N; Rakotondravohitra, L; Ramirez, M A; Ransome, R D; Ray, H; Ren, L; Rodrigues, P A; Ruterbories, D; Schellman, H; Schmitz, D W; Sobczyk, J T; Salinas, C J Solano; Tagg, N; Tice, B G; Valencia, E; Walton, T; Wolcott, J; Yepes-Ramirez, H; Zavala, G; Zhang, D; Ziemer, B P

    2015-01-01

    Single neutral pion production via muon antineutrino charged-current interactions in plastic scintillator (CH) is studied using the \\minerva detector exposed to the NuMI low-energy, wideband antineutrino beam at Fermilab. Measurement of this process constrains models of neutral pion production in nuclei, which is important because the neutral-current analog is a background for $\\bar{\

  6. The detector system of the Daya Bay reactor neutrino experiment

    Science.gov (United States)

    An, F. P.; Bai, J. Z.; Balantekin, A. B.; Band, H. R.; Beavis, D.; Beriguete, W.; Bishai, M.; Blyth, S.; Brown, R. L.; Butorov, I.; Cao, D.; Cao, G. F.; Cao, J.; Carr, R.; Cen, W. R.; Chan, W. T.; Chan, Y. L.; Chang, J. F.; Chang, L. C.; Chang, Y.; Chasman, C.; Chen, H. Y.; Chen, H. S.; Chen, M. J.; Chen, Q. Y.; Chen, S. J.; Chen, S. M.; Chen, X. C.; Chen, X. H.; Chen, X. S.; Chen, Y. X.; Chen, Y.; Cheng, J. H.; Cheng, J.; Cheng, Y. P.; Cherwinka, J. J.; Chidzik, S.; Chow, K.; Chu, M. C.; Cummings, J. P.; de Arcos, J.; Deng, Z. Y.; Ding, X. F.; Ding, Y. Y.; Diwan, M. V.; Dong, L.; Dove, J.; Draeger, E.; Du, X. F.; Dwyer, D. A.; Edwards, W. R.; Ely, S. R.; Fang, S. D.; Fu, J. Y.; Fu, Z. W.; Ge, L. Q.; Ghazikhanian, V.; Gill, R.; Goett, J.; Gonchar, M.; Gong, G. H.; Gong, H.; Gornushkin, Y. A.; Grassi, M.; Greenler, L. S.; Gu, W. Q.; Guan, M. Y.; Guo, R. P.; Guo, X. H.; Hackenburg, R. W.; Hahn, R. L.; Han, R.; Hans, S.; He, M.; He, Q.; He, W. S.; Heeger, K. M.; Heng, Y. K.; Higuera, A.; Hinrichs, P.; Ho, T. H.; Hoff, M.; Hor, Y. K.; Hsiung, Y. B.; Hu, B. Z.; Hu, L. M.; Hu, L. J.; Hu, T.; Hu, W.; Huang, E. C.; Huang, H. Z.; Huang, H. X.; Huang, P. W.; Huang, X.; Huang, X. T.; Huber, P.; Hussain, G.; Isvan, Z.; Jaffe, D. E.; Jaffke, P.; Jen, K. L.; Jetter, S.; Ji, X. P.; Ji, X. L.; Jiang, H. J.; Jiang, W. Q.; Jiao, J. B.; Johnson, R. A.; Joseph, J.; Kang, L.; Kettell, S. H.; Kohn, S.; Kramer, M.; Kwan, K. K.; Kwok, M. W.; Kwok, T.; Lai, C. Y.; Lai, W. C.; Lai, W. H.; Langford, T. J.; Lau, K.; Lebanowski, L.; Lee, J.; Lee, M. K. P.; Lei, R. T.; Leitner, R.; Leung, J. K. C.; Lewis, C. A.; Li, B.; Li, C.; Li, D. J.; Li, F.; Li, G. S.; Li, J.; Li, N. Y.; Li, Q. J.; Li, S. F.; Li, S. C.; Li, W. D.; Li, X. B.; Li, X. N.; Li, X. Q.; Li, Y.; Li, Y. F.; Li, Z. B.; Liang, H.; Liang, J.; Lin, C. J.; Lin, G. L.; Lin, P. Y.; Lin, S. X.; Lin, S. K.; Lin, Y. C.; Ling, J. J.; Link, J. M.; Littenberg, L.; Littlejohn, B. R.; Liu, B. J.; Liu, C.; Liu, D. W.; Liu, H.; Liu, J. L.; Liu, J. C.; Liu, S.; Liu, S. S.; Liu, X.; Liu, Y. B.; Lu, C.; Lu, H. Q.; Lu, J. S.; Luk, A.; Luk, K. B.; Luo, T.; Luo, X. L.; Ma, L. H.; Ma, Q. M.; Ma, X. Y.; Ma, X. B.; Ma, Y. Q.; Mayes, B.; McDonald, K. T.; McFarlane, M. C.; McKeown, R. D.; Meng, Y.; Mitchell, I.; Mohapatra, D.; Monari Kebwaro, J.; Morgan, J. E.; Nakajima, Y.; Napolitano, J.; Naumov, D.; Naumova, E.; Newsom, C.; Ngai, H. Y.; Ngai, W. K.; Nie, Y. B.; Ning, Z.; Ochoa-Ricoux, J. P.; Olshevskiy, A.; Pagac, A.; Pan, H.-R.; Patton, S.; Pearson, C.; Pec, V.; Peng, J. C.; Piilonen, L. E.; Pinsky, L.; Pun, C. S. J.; Qi, F. Z.; Qi, M.; Qian, X.; Raper, N.; Ren, B.; Ren, J.; Rosero, R.; Roskovec, B.; Ruan, X. C.; Sands, W. R.; Seilhan, B.; Shao, B. B.; Shih, K.; Song, W. Y.; Steiner, H.; Stoler, P.; Stuart, M.; Sun, G. X.; Sun, J. L.; Tagg, N.; Tam, Y. H.; Tanaka, H. K.; Tang, W.; Tang, X.; Taychenachev, D.; Themann, H.; Torun, Y.; Trentalange, S.; Tsai, O.; Tsang, K. V.; Tsang, R. H. M.; Tull, C. E.; Tung, Y. C.; Viaux, N.; Viren, B.; Virostek, S.; Vorobel, V.; Wang, C. H.; Wang, L. S.; Wang, L. Y.; Wang, L. Z.; Wang, M.; Wang, N. Y.; Wang, R. G.; Wang, T.; Wang, W.; Wang, W. W.; Wang, X. T.; Wang, X.; Wang, Y. F.; Wang, Z.; Wang, Z.; Wang, Z. M.; Webber, D. M.; Wei, H. Y.; Wei, Y. D.; Wen, L. J.; Wenman, D. L.; Whisnant, K.; White, C. G.; Whitehead, L.; Whitten, C. A.; Wilhelmi, J.; Wise, T.; Wong, H. C.; Wong, H. L. H.; Wong, J.; Wong, S. C. F.; Worcester, E.; Wu, F. F.; Wu, Q.; Xia, D. M.; Xia, J. K.; Xiang, S. T.; Xiao, Q.; Xing, Z. Z.; Xu, G.; Xu, J. Y.; Xu, J. L.; Xu, J.; Xu, W.; Xu, Y.; Xue, T.; Yan, J.; Yang, C. G.; Yang, L.; Yang, M. S.; Yang, M. T.; Ye, M.; Yeh, M.; Yeh, Y. S.; Yip, K.; Young, B. L.; Yu, G. Y.; Yu, Z. Y.; Zeng, S.; Zhan, L.; Zhang, C.; Zhang, F. H.; Zhang, H. H.; Zhang, J. W.; Zhang, K.; Zhang, Q. X.; Zhang, Q. M.; Zhang, S. H.; Zhang, X. T.; Zhang, Y. C.; Zhang, Y. H.; Zhang, Y. M.; Zhang, Y. X.; Zhang, Y. M.; Zhang, Z. J.; Zhang, Z. Y.; Zhang, Z. P.; Zhao, J.; Zhao, Q. W.; Zhao, Y. F.; Zhao, Y. B.; Zheng, L.; Zhong, W. L.; Zhou, L.; Zhou, N.; Zhou, Z. Y.; Zhuang, H. L.; Zimmerman, S.; Zou, J. H.

    2016-03-01

    The Daya Bay experiment was the first to report simultaneous measurements of reactor antineutrinos at multiple baselines leading to the discovery of νbare oscillations over km-baselines. Subsequent data has provided the world's most precise measurement of sin2 2θ13 and the effective mass splitting Δ mee2. The experiment is located in Daya Bay, China where the cluster of six nuclear reactors is among the world's most prolific sources of electron antineutrinos. Multiple antineutrino detectors are deployed in three underground water pools at different distances from the reactor cores to search for deviations in the antineutrino rate and energy spectrum due to neutrino mixing. Instrumented with photomultiplier tubes, the water pools serve as shielding against natural radioactivity from the surrounding rock and provide efficient muon tagging. Arrays of resistive plate chambers over the top of each pool provide additional muon detection. The antineutrino detectors were specifically designed for measurements of the antineutrino flux with minimal systematic uncertainty. Relative detector efficiencies between the near and far detectors are known to better than 0.2%. With the unblinding of the final two detectors' baselines and target masses, a complete description and comparison of the eight antineutrino detectors can now be presented. This paper describes the Daya Bay detector systems, consisting of eight antineutrino detectors in three instrumented water pools in three underground halls, and their operation through the first year of eight detector data-taking.

  7. Nuclear reactors Monitoring using neutrinos detectors1

    International Nuclear Information System (INIS)

    We study the feasibility to use antineutrinos detectors for monitoring of nuclear reactors. Using a simple model of fission shower with two components, we illustrate how the numbers of antineutrinos detected at a distance L from the reactor depend on the composition of the nuclear combustible and how it could be used for nuclear safeguards policy.

  8. Testing the schemes of lepton charge conservation law in the neutrino experiments

    International Nuclear Information System (INIS)

    In terms of various model about conservation of lepton charge one studied processes involving leptons of two first generations simultaneously. On the basis of the current (V-A)- and (V+A)-interactions of weak currents one derived and analyzed cross sections of reactions of inelastic neutrino (antineutrino)-electron and neutrino(antineutrino)-muon scatterings with regard of spiralities of charged leptons

  9. Neutrino-4 experiment on the search for a sterile neutrino at the SM-3 reactor

    Energy Technology Data Exchange (ETDEWEB)

    Serebrov, A. P., E-mail: serebrov@pnpi.spb.ru; Ivochkin, V. G.; Samoylov, R. M.; Fomin, A. K.; Zinoviev, V. G.; Neustroev, P. V.; Golovtsov, V. L.; Gruzinsky, N. V.; Solovey, V. A.; Chernyi, A. V.; Zherebtsov, O. M. [National Research Centre “Kurchatov Institute,”, Konstantinov Petersburg Nuclear Physics Institute (Russian Federation); Martemyanov, V. P.; Tsinoev, V. G.; Tarasenkov, V. G.; Aleshin, V. I. [National Research Centre “Kurchatov Institute,” (Russian Federation); Petelin, A. L.; Pavlov, S. V.; Izhutov, A. L.; Sazontov, S. A.; Ryazanov, D. K. [State Scientific Centre Research Institute of Atomic Reactors (Russian Federation); and others

    2015-10-15

    In view of the possibility of the existence of a sterile neutrino, test measurements of the dependence of the reactor antineutrino flux on the distance from the reactor core has been performed on SM-2 reactor with the Neutrino-2 detector model in the range of 6–11 m. Prospects of the search for reactor antineutrinos at short distances have been discussed.

  10. Neutrino science and applications

    International Nuclear Information System (INIS)

    50 years of fundamental antineutrino detection experiments at nuclear reactors have laid the groundwork for a new discipline - Applied Antineutrino Physics. Using well known detection methods, we and others worldwide have shown that antineutrino detectors can be used to monitor the operational status, power, and fissile content of reactors, non-intrusively and in real time. These capabilities are potentially relevant for global nonproliferation and nuclear materials control regimes. In the past few years, we have begun to explore several approaches to improving antineutrino detection. If successful, these could reduce detector footprints by a factor of ten, permit above-ground detection of reactor antineutrinos, or increase the standoff detection capability for small reactors out to hundreds of kilometers. I will describe our current and proposed activities in these areas of research, and point to the many connections of this work to ongoing efforts in fundamental neutrino science and particle astrophysics. (author)

  11. Sensitivity and Discovery Potential of the PROSPECT Experiment

    CERN Document Server

    ,

    2015-01-01

    Measurements of the reactor antineutrino flux and spectrum compared to model predictions have revealed an apparent deficit in the interaction rates of reactor antineutrinos and an unexpected spectral deviation. PROSPECT, the Precision Reactor Oscillation Spectrum measurement, is designed to make a precision measurement of the antineutrino spectrum from a research reactor and search for signs of an eV-scale sterile neutrino. PROSPECT will be located at the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory and make use of a Highly Enriched Uranium reactor for a measurement of the pure U-235 antineutrino spectrum. An absolute measurement of this spectrum will constrain reactor models and improve our understanding of the reactor antineutrino spectrum. Additionally, the planned 3-ton lithium-doped liquid scintillator detector is ideally suited to perform a search for sterile neutrinos. This talk will focus on the sensitivity and discovery potential of PROSPECT and the detector design to achieve the...

  12. Geoneutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Machulin, I. N., E-mail: machulin@lngs.infn.it [National Research Center Kurchatov Institute (Russian Federation); Collaboration: Borexino Collaboration

    2015-12-15

    Academician M.A. Markov in the 1960s first proposed detecting the electron antineutrino in the reaction of inverse beta decay on a proton to study the processes inside the Earth. The radioactive isotopes {sup 238}U, {sup 232}Th, and {sup 40}K present in our planet decay with radiation of neutrinos (antineutrinos). Neutrinos that are produced reach the Earth’s surface practically without absorption and carry information about the internal structure of the planet. However, because of the smallness of the antineutrino fluxes and interaction cross sections with matter, antineutrinos of geological origin were first registered in only two experiments (Borexino and Kamland) in recent years. The experimental observation of antineutrinos from the isotope decays in the depths of the Earth is the only way to study the radiation in our planetary interior.

  13. Physical Review Letters

    OpenAIRE

    An, F. P.; Bai, J. Z.; Balantekin, A. B.; Band, H. R.; Beavis, D; Beriguete, W.; Bishai, M.; Blyth, S.; Boddy, K; Brown, R. L.; Cai, B.; Cao, G. F.; J. Cao; Carr, R.; Chan, W. T.

    2012-01-01

    The Daya Bay Reactor Neutrino Experiment has measured a nonzero value for the neutrino mixing angle 0(13) with a significance of 5.2 standard deviations. Antineutrinos from six 2.9 GW(th) reactors were detected in six antineutrino detectors deployed in two near (flux-weighted baseline 470 m and 576 m) and one far (1648 m) underground experimental halls. With a 43 000 ton-GW(th)-day live-time exposure in 55 days, 10 416 (80 376) electron-antineutrino candidates were detected at the far hall (n...

  14. The PROSPECT Physics Program

    CERN Document Server

    Ashenfelter, J; Band, H R; Barclay, G; Bass, C D; Berish, D; Bowden, N S; Bowes, A; Bryan, C D; Brodsky, J P; Cherwinka, J J; Chu, R; Classen, T; Commeford, K; Davee, D; Dean, D; Deichert, G; Diwan, M V; Dolinski, M J; Dolph, J; Gaison, J K; Galindo-Uribarri, A; Gilje, K; Glenn, A; Goddard, B W; Green, M; Han, K; Hans, S; Heeger, K M; Heffron, B; Jaffe, D E; Jones, D; Langford, T J; Littlejohn, B R; Caicedo, D A Martinez; McKeown, R D; Mendenhall, M P; Mueller, P; Mumm, H P; Napolitano, J; Neilson, R; Norcini, D; Pushin, D; Qian, X; Romero, E; Rosero, R; Seilhan, B S; Sharma, R; Sheets, S; Surukuchi, P T; Varner, R L; Viren, B; Wang, W; White, B; White, C; Wilhelmi, J; Williams, C; Wise, T; Yao, H; Yeh, M; Yen, Y -R; Zangakis, G; Zhang, C; Zhang, X

    2015-01-01

    The Precision Reactor Oscillation and Spectrum Experiment, PROSPECT, is designed to make a precise measurement of the antineutrino spectrum from a highly-enriched uranium reactor and probe eV-scale sterile neutrinos by searching for neutrino oscillations over meter-long distances. PROSPECT is conceived as a 2-phase experiment utilizing segmented $^6$Li-doped liquid scintillator detectors for both efficient detection of reactor antineutrinos through the inverse beta decay reaction and excellent background discrimination. PROSPECT Phase I consists of a movable 3-ton antineutrino detector at distances of 7 - 12 m from the reactor core. It will probe the best-fit point of the $\

  15. Charakterisierung der Double Chooz–Photomultiplier

    OpenAIRE

    Huth, L.

    2012-01-01

    The Double Chooz (DC) experiment is a reactor electron anti-neutrino oscillation experiment, which is located in France. The main goal of DC is to measure the last unknown neutrino mixing angle θ13 of the transformation matrix UPNMS using electron anti-neutrinos, produced by two identical nuclear reactors. The detection of an electron anti-neutrino takes place via light emission produced in the inverse β-decay. This light is detected by photomultipliers. The electronics in the base of the pho...

  16. Photomultiplier Tube System for the Daya Bay Experiment

    International Nuclear Information System (INIS)

    The Daya Bay Reactor Neutrino Experiment is designed to measure sin2(2θ13) to 0.01 by performing a relative measurement of electron antineutrino events via inverse β decay in the near and far detectors. The antineutrino detectors will be placed in water pools and surrounded by at least 2.5m of water to suppress background. The water pools also serve as Cherenkov detectors for tagging cosmic-ray muons that can generate background. Details of the photomultiplier tube assemblies used in the antineutrino detectors and the water Cherenkov counters are presented.

  17. The detector system of the Daya Bay reactor neutrino experiment

    OpenAIRE

    An, F. P.; Carr, R; McKeown, R.D.; Tsang, R. H. M.; Wu, F. F.

    2016-01-01

    The Daya Bay experiment was the first to report simultaneous measurements of reactor antineutrinos at multiple baselines leading to the discovery of ν¯e oscillations over km-baselines. Subsequent data has provided the world׳s most precise measurement of sin^2 2θ_(13) and the effective mass splitting Δm^2_(ee). The experiment is located in Daya Bay, China where the cluster of six nuclear reactors is among the world׳s most prolific sources of electron antineutrinos. Multiple antineutrino detect...

  18. Direct extraction of nuclear effects in quasielastic scattering on carbon

    CERN Document Server

    Wilkinson, Callum

    2016-01-01

    The differences between neutrino and antineutrino CCQE cross sections measured on hydrocarbon targets are due to fundamental differences in the cross section, different neutrino and antineutrino fluxes from the same beamline, and the additional interactions on hydrogen for antineutrinos that are absent for neutrinos. In this analysis we correct for the former two differences to extract a constraint on the ratio of the CCQE cross section for free and bound protons from MINERvA and MiniBooNE data. This measures nuclear effects in carbon, and we compare this measurement to models.

  19. Ultra-high energy neutrino dispersion in plasma and radiative transition $\

    CERN Document Server

    Kuznetsov, A V; Shitova, A M

    2011-01-01

    Qualitative analysis of additional energy of neutrino and antineutrino in plasma is performed. A general expression for the neutrino self-energy operator is obtained in the case of ultra-high energies when the local limit of the weak interaction is not valid. The neutrino and antineutrino additional energy in plasma is calculated using the dependence of the $W$ and $Z$--boson propagators on the momentum transferred. The kinematical region for the neutrino radiative transition (the so-called "neutrino spin light") is established for some important astrophysical cases. For high energy neutrino and antineutrino, dominating transition channels in plasma, $\

  20. Solid electron sources for the energy scale monitoring in the KATRIN experiment

    CERN Document Server

    Zbořil, Miroslav; Vénos, D

    The KArlsruhe TRItium Neutrino (KATRIN) experiment represents a next-generation tritium $\\beta$-decay experiment designed to perform a high precision direct measurement of the electron anti-neutrino mass m($\

  1. Hidden Glashow resonance in neutrino-nucleus collisions

    CERN Document Server

    Alikhanov, I

    2015-01-01

    Today it is widely believed that $s$-channel excitation of an on-shell~$W$ boson, commonly known as the Glashow resonance, can be initiated in matter only by the electron antineutrino in the process $\\bar\

  2. magnetic horn

    CERN Multimedia

    Neutrinos and antineutrinos are ideal for probing the weak force because it is effectively the only force they feel. How were they made? Protons fired into a metal target produce a tangle of secondary particles. A magnetic horn like this one, invented by Simon Van der Meer, selected pions and focused them into a sharp beam. Pions decay into muons and neutrinos or antineutrinos. The muons were stopped in a wall of 3000 tons of iron and 1000 tons of concrete, leaving the neutrinos or antineutrinos to reach the Gargamelle bubble chamber. A simple change of magnetic field direction on the horn flipped between focusing positively- or negatively-charged pion beams, and so between neutrinos and antineutrinos.

  3. Quest for the Nuclear Georeactor

    OpenAIRE

    de Meijer, R. J.; van der Graaf, E. R.; Jungmann, K. P.

    2004-01-01

    The paper focuses on a proposal for an underground antineutrino antenna to further develop the dectection of these particles as a tool to map the distribution of radiogenic heat sources, such as the natural radionuclides and a hypothetical nuclear georeactor.

  4. Independent Measurement of Theta13 via Neutron Capture on Hydrogen at Daya Bay

    CERN Document Server

    An, F P; Band, H R; Beriguete, W; Bishai, M; Blyth, S; Butorov, I; Cao, G F; Cao, J; Chan, Y L; Chang, J F; Chang, L C; Chang, Y; Chasman, C; Chen, H; Chen, Q Y; Chen, S M; Chen, X; Chen, Y X; Chen, Y; Cheng, Y P; Cherwinka, J J; Chu, M C; Cummings, J P; de Arcos, J; Deng, Z Y; Ding, Y Y; Diwan, M V; Draeger, E; Du, X F; Dwyer, D A; Edwards, W R; Ely, S R; Fu, J Y; Ge, L Q; Gill, R; Gonchar, M; Gong, G H; Gong, H; Gornushkin, Y A; Gu, W Q; Guan, M Y; Guo, X H; Hackenburg, R W; Han, G H; Hans, S; He, M; Heeger, K M; Heng, Y K; Hinrichs, P; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, L M; Hu, L J; Hu, T; Hu, W; Huang, E; Huang, H; Huang, X T; Huber, P; Hussain, G; Isvan, Z; Jaffe, D E; Jaffke, P; Jen, K L; Jetter, S; Ji, X P; Ji, X L; Jiang, H J; Jiao, J B; Johnson, R A; Kang, L; Kettell, S H; Kramer, M; Kwan, K K; Kwok, M W; Kwok, T; Lai, W C; Lau, K; Lebanowski, L; Lee, J; Lei, R T; Leitner, R; Leung, A; Leung, J K C; Lewis, C A; Li, D J; Li, F; Li, G S; Li, Q J; Li, W D; Li, X N; Li, X Q; Li, Y F; Li, Z B; Liang, H; Lin, C J; Lin, G L; Lin, P Y; Lin, S K; Lin, Y C; Ling, J J; Link, J M; Littenberg, L; Littlejohn, B R; Liu, D W; Liu, H; Liu, J L; Liu, J C; Liu, S S; Liu, Y B; Lu, C; Lu, H Q; Luk, K -B; Ma, Q M; Ma, X Y; Ma, X B; Ma, Y Q; McDonald, K T; McFarlane, M C; McKeown, R D; Meng, Y; Mitchell, I; Kebwaro, J Monari; Nakajima, Y; Napolitano, J; Naumov, D; Naumova, E; Nemchenok, I; Ngai, H Y; Ning, Z; Ochoa-Ricoux, J P; Olshevski, A; Patton, S; Pec, V; Peng, J C; Piilonen, L E; Pinsky, L; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Raper, N; Ren, B; Ren, J; Rosero, R; Roskovec, B; Ruan, X C; Shao, B B; Steiner, H; Sun, G X; Sun, J L; Y,; Tam, H; Tang, X; Themann, H; Tsang, K V; Tsang, R H M; Tull, C E; Tung, Y C; Viren, B; Vorobel, V; Wang, C H; Wang, L S; Wang, L Y; Wang, M; Wang, N Y; Wang, R G; Wang, W; Wang, W W; Wang, X; Wang, Y F; Wang, Z; Wang, Z M; Webber, D M; Wei, H Y; Wei, Y D; Wen, L J; Whisnant, K; White, C G; Whitehead, L; Wise, T; Wong, H L H; Wong, S C F; Worcester, E; Wu, Q; Xia, D M; Xia, J K; Xia, X; Xing, Z Z; Xu, J Y; Xu, J L; Xu, J; Xu, Y; Xue, T; Yan, J; Yang, C C; Yang, L; Yang, M S; Yang, M T; Ye, M; Yeh, M; Yeh, Y S; Young, B L; Yu, G Y; Yu, J Y; Yu, Z Y; Zang, S L; Zeng, B; Zhan, L; Zhang, C; Zhang, F H; Zhang, J W; Zhang, Q M; Zhang, Q; Zhang, S H; Zhang, Y C; Zhang, Y M; Zhang, Y H; Zhang, Y X; Zhang, Z J; Zhang, Z Y; Zhang, Z P; Zhao, J; Zhao, Q W; Zhao, Y; Zhao, Y B; Zheng, L; Zhong, W L; Zhou, L; Zhou, Z Y; Zhuang, H L; Zou, J H

    2014-01-01

    A new measurement of the $\\theta_{13}$ mixing angle has been obtained at the Daya Bay Reactor Neutrino Experiment via the detection of inverse beta decays tagged by neutron capture on hydrogen. The antineutrino events for hydrogen capture are distinct from those for gadolinium capture with largely different systematic uncertainties, allowing a determination independent of the gadolinium-capture result and an improvement on the precision of $\\theta_{13}$ measurement. With a 217-day antineutrino data set obtained with six antineutrino detectors and from six 2.9 GW$_{th}$ reactors, the rate deficit observed at the far hall is interpreted as $\\sin^22\\theta_{13}=0.083\\pm0.018$ in the three-flavor oscillation model. When combined with the gadolinium-capture result from Daya Bay, we obtain $\\sin^22\\theta_{13}=0.089\\pm0.008$ as the final result for the six-antineutrino-detector configuration of the Daya Bay experiment.

  5. Search for stellar gravitational collapse by MACRO: Characteristics and results

    International Nuclear Information System (INIS)

    The first MACRO lower supermodule has been sensitive to antineutrinos from stellar gravitational collapse since spring 1989. The results with the 44 tonnes of liquid scintillator which have been instrumented to search for stellar gravitational collapse are discussed here. (orig.)

  6. Neutrino oscillations

    International Nuclear Information System (INIS)

    Lecture notes on neutrino oscillations are given, including some background about neutrino mixing and masses, descriptions of flavour oscillations and experimental attempts to detect them, matter effects and neutrino-antineutrino oscillations. (U.K.)

  7. Disappearing neutrinos at KamLAND suport the case for neutrino mass

    CERN Multimedia

    Johnson, G

    2002-01-01

    Measurements from KamLAND, show that anti-neutrinos emanating from nearby nuclear reactors are "disappearing," which indicates they have mass and can oscillate or change from one type to another (2 pages)

  8. Reactor Neutrino Spectra

    CERN Document Server

    Hayes, A C

    2016-01-01

    We present a review of the antineutrino spectra emitted from reactors. Knowledge of these and their associated uncertainties are crucial for neutrino oscillation studies. The spectra used to-date have been determined by either conversion of measured electron spectra to antineutrino spectra or by summing over all of the thousands of transitions that makeup the spectra using modern databases as input. The uncertainties in the subdominant corrections to beta-decay plague both methods, and we provide estimates of these uncertainties. Improving on current knowledge of the antineutrino spectra from reactors will require new experiments. Such experiments would also address the so-called reactor neutrino anomaly and the possible origin of the shoulder observed in the antineutrino spectra measured in recent high-statistics reactor neutrino experiments.

  9. A new MC-based method to evaluate the fission fraction uncertainty at reactor neutrino experiment

    OpenAIRE

    Ma, X. B.; Qiu, R. M.; Y. X. Chen

    2016-01-01

    Uncertainties of fission fraction is an important uncertainty source for the antineutrino flux prediction in a reactor antineutrino experiment. A new MC-based method of evaluating the covariance coefficients between isotopes was proposed. It was found that the covariance coefficients will varying with reactor burnup and which may change from positive to negative because of fissioning balance effect, for example, the covariance coefficient between $^{235}$U and $^{239}$Pu changes from 0.15 to ...

  10. Limits on CPT violation from solar neutrinos

    CERN Document Server

    Diaz, Jorge S

    2016-01-01

    Violations of CPT invariance can induce neutrino-to-antineutrino transitions. We study this effect for solar neutrinos and use the upper bound on the solar neutrino-to-antineutrino transition probability from the KamLAND experiment to constrain CPT-symmetry-violating coefficients of the general Standard-Model Extension. The long propagation distance from the Sun to the Earth allows us to improve existing limits by factors ranging from about a thousand to $10^{11}$.

  11. Limits on C P T violation from solar neutrinos

    Science.gov (United States)

    Díaz, Jorge S.; Schwetz, Thomas

    2016-05-01

    Violations of C P T invariance can induce neutrino-to-antineutrino transitions. We study this effect for solar neutrinos and use the upper bound on the solar neutrino-to-antineutrino transition probability from the KamLAND experiment to constrain C P T -symmetry-violating coefficients of the general Standard-Model Extension. The long propagation distance from the Sun to the Earth allows us to improve existing limits by factors ranging from about a thousand to 1011 .

  12. Limits on Active to Sterile Neutrino Oscillations from Disappearance Searches in the MINOS, Daya Bay, and Bugey-3 Experiments

    OpenAIRE

    Bay, Daya; Collaborations, MINOS+; :; Adamson, P.; An, F. P.; Anghel, I.(University of Illinois at Chicago (UIC), Chicago, U.S.A); Aurisano, A.; Balantekin, A. B.; Band, H R.; Barr, G.; Bishai, M.; Blake, A.; Bock, S. Blyth G. J.; Bogert, D.; Cao, D.

    2016-01-01

    Searches for a light sterile neutrino have been independently performed by the MINOS and the Daya Bay experiments using the muon (anti)neutrino and electron antineutrino disappearance channels, respectively. In this Letter, results from both experiments are combined with those from the Bugey-3 reactor neutrino experiment to constrain oscillations into light sterile neutrinos. The three experiments are sensitive to complementary regions of parameter space, enabling the combined analysis to pro...

  13. Improved Search for a Light Sterile Neutrino with the Full Configuration of the Daya Bay Experiment

    OpenAIRE

    The Daya Bay collaboration; An, F. P.; Balantekin, A. B.; Band, H R.; Bishai, M.; Blyth, S.; Cao, D.; Cao, G. F.; Cao, J; Cen, W. R.; Chan, Y.L.; Chang, J. F.; Chang, L. C.; Chang, Y.; Chen, H. S.

    2016-01-01

    This Letter reports an improved search for light sterile neutrino mixing in the electron antineutrino disappearance channel with the full configuration of the Daya Bay Reactor Neutrino Experiment. With an additional 404 days of data collected in eight antineutrino detectors, this search benefits from 3.6 times the statistics available to the previous publication, as well as from improvements in energy calibration and background reduction. A relative comparison of the rate and energy spectrum ...

  14. New measurement of θ_(13) via neutron capture on hydrogen at Daya Bay

    OpenAIRE

    An, F. P.; McKeown, R. D.

    2016-01-01

    This article reports an improved independent measurement of neutrino mixing angle θ_(13) at the Daya Bay Reactor Neutrino Experiment. Electron antineutrinos were identified by inverse β-decays with the emitted neutron captured by hydrogen, yielding a data set with principally distinct uncertainties from that with neutrons captured by gadolinium. With the final two of eight antineutrino detectors installed, this study used 621 days of data including the previously reported 217-day data set wit...

  15. Time-Energy Uncertainty Relations for Neutrino Oscillation and M\\"Ossbauer Neutrino Experiment

    OpenAIRE

    Bilenky, S. M.; von Feilitzsch, F.; Potzel, W.

    2008-01-01

    Using the Mandelstam-Tamm method we derive time-energy uncertainty relations for neutrino oscillations. We demonstrate that the small energy uncertainty of antineutrinos in a recently considered experiment with recoilless resonant (M\\"ossbauer) production and absorption of tritium antineutrinos is in conflict with the energy uncertainty which, according to the time-energy uncertainty relation, is necessary for neutrino oscillations to happen. A M\\"ossbauer neutrino experiment could provide a ...

  16. The first result of the neutrino magnetic moment measurement in the GEMMA experiment

    CERN Document Server

    Beda, A G; Demidova, E V; Egorov, V G; Gavrilov, M G; Shirchenko, M V; Starostin, A S; Vylov, T

    2007-01-01

    The first result of the neutrino magnetic moment measurement at the Kalininskaya Nuclear Power Plant (KNPP) with the GEMMA spectrometer is presented. An antineutrino-electron scattering is investigated. A high-purity germanium detector of 1.5 kg placed 13.9 m away from the 3 GW reactor core is used in the spectrometer. The antineutrino flux is $2.73\\times 10^{13} \

  17. Resonant scattering and charm showers in ultrahigh-energy neutrino interactions

    Science.gov (United States)

    Wilczek, F.

    1985-01-01

    Electron antineutrinos with energy of about 7 x 10 to the 6th GeV have much-enhanced cross sections due to W-boson production off electrons. Possible signals due to cosmic-ray sources are estimated. Higher-energy antineutrinos can efficiently produce a W accompanied by radiation. Another possibility, which could lead to shadowing at modest depths, is resonant production of a charged Higgs particle. The importance of muon production by charm showers in rock is pointed out.

  18. Supernova Early Warning in Daya Bay Reactor Neutrino Experiment

    OpenAIRE

    Hanyu Wei for the Daya Bay collaboration

    2013-01-01

    Providing an early warning of a galactic supernova using neutrino signals is of importance in studying both supernova dynamics and neutrino physics. The Daya Bay reactor neutrino experiment, with a unique feature of multiple liquid scintillator detectors separated in space, is sensitive to the full energy spectrum of supernova burst electron-antineutrinos. By deploying 8 Antineutrino Detectors (ADs) in three different experimental halls, we obtain a more powerful and prompt rejection of muon ...

  19. Do solar neutrinos constrain the electromagnetic properties of the neutrino?

    OpenAIRE

    Friedland, Alexander

    2005-01-01

    It is of great interest whether the recent KamLAND bound on the flux of electron antineutrinos from the Sun constrains the electromagnetic properties of the neutrino. We examine the efficiency of the electron antineutrino production in the solar magnetic fields, assuming the neutrinos are Majorana particles with a relatively large transition moment. We consider fields both in the radiative and convective zones of the Sun, with physically plausible strengths, and take into account the recently...

  20. Black Holes and Gravitational Properties of Antimatter

    OpenAIRE

    Hajdukovic, Dragan Slavkov

    2006-01-01

    The gravitational properties of antimatter are still a secret of nature. One outstanding possibility is that there is a gravitational repulsion between matter and antimatter (in short we call it antigravity). We argue that in the case of antigravity the collapse of a black hole doesn't end with singularity and that deep inside the horizon, the gravitational field may be sufficiently strong to create (from the vacuum) neutrino-antineutrino pairs of all flavours. The created antineutrinos (neut...

  1. Neutral Current $\

    CERN Document Server

    Chauhan, S; Singh, S K

    2011-01-01

    We calculate cross sections for the neutral current induced neutrino/antineutrino reaction from $^{208}Pb$ target and applied it to study Supernova neutrino event rates. The calculations are done in local density approximation taking into account Pauli blocking, Fermi motion effects and renormalization of weak transition strengths in the nuclear medium. The numerical results for the neutrino nucleus total cross sections have been averaged over the various Supernova neutrino/antineutrino fluxes available in literature.

  2. Weak production of strange particles off the nucleon

    CERN Document Server

    Alam, M Rafi; Athar, M Sajjad; Alvarez-Ruso, L; Vacas, M J Vicente

    2013-01-01

    The strange particle production off the nucleon induced by neutrinos and antineutrinos is investigated at low and intermediate energies. We develop a microscopic model based on the SU(3) chiral Lagrangian. The studied mechanisms are the main source of single kaon production for (anti)neutrino energies up to 1.5 GeV. Using this model we have also studied the associated production of kaons and hyperons. The cross sections are large enough to be measured by experiments such as MINER$\

  3. Neutrino transition magnetic moments and the solar magnetic field on the light of the Kamland evidence

    CERN Document Server

    Antonelli, V; Picariello, M; Pulido, J; Torrente-Lujan, E

    2003-01-01

    We present here a recopilation of recent results about the possibility of detecting solar electron antineutrinos produced by solar core and convective magnetic fields. These antineutrinos are predicted by spin-flavor oscillations at a significant rate even if this mechanism is not the leading solution to the SNP. Using the recent Kamland results and assuming a concrete model for antineutrino production by spin-flavor precession in the convective zone based on chaotic magnetic fields,we obtain bounds on the flux of solar antineutrinos, on the average conversion neutrino-antineutrino probability and on intrinsic neutrino magnetic moment. In the most conservative case, $\\mu\\lsim 2.5\\times 10^{-11} \\mu_B$ (95% CL). When studying the effects of a core magnetic field, we find in the weak limit a scaling of the antineutrino probability with respect to the magnetic field profile in the sense that the same probability function can be reproduced by any profile with a suitable peak field value. In this way the solar ele...

  4. Intensive neutrino source on the base of lithium converter

    CERN Document Server

    Lyashuk, V I

    2015-01-01

    An intensive antineutrino source with a hard spectrum (with energy up to 13 MeV, average energy 6.5 MeV) can be realized on the base of beta-decay of short living isotope 8Li (0.84 s). The 8Li isotope (generated in activation of 7Li isotope) is a prime perspective antineutrino source owing to the hard antineutrino spectrum and square dependence of cross section on the energy. Up today nuclear reactors are the most intensive neutrino sources. Antineutrino reactor spectra have large uncertainties in the summary antineutrino spectrum at energy E>6 MeV. Use of 8Li isotope allows to decrease sharply the uncertainties or to exclude it completely. An intensive neutron fluxes are requested for rapid generation of 8Li isotope. The installations on the base of nuclear reactors can be an alternative for nuclear reactors as traditional neutron sources. It is possible creation of neutrino sources another in principle: on the base of tandem of accelerators, neutron generating targets and lithium converter. An intensive neu...

  5. PROSPECT - A precision oscillation and spectrum experiment

    CERN Document Server

    ,

    2015-01-01

    Segmented antineutrino detectors placed near a compact research reactor provide an excellent opportunity to probe short-baseline neutrino oscillations and precisely measure the reactor antineutrino spectrum. Close proximity to a reactor combined with minimal overburden yield a high background environment that must be managed through shielding and detector technology. PROSPECT is a new experimental effort to detect reactor antineutrinos from the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory, managed by UT Battelle for the U.S. Department of Energy. The detector will use novel lithium-loaded liquid scintillator capable of neutron/gamma pulse shape discrimination and neutron capture tagging. These enhancements improve the ability to identify neutrino inverse-beta decays and reject background events in analysis. Results from these efforts will be covered along with their implications for an oscillation search and a precision spectrum measurement.

  6. Search for a Light Sterile Neutrino at Daya Bay

    CERN Document Server

    An, F P; Band, H R; Beriguete, W; Bishai, M; Blyth, S; Butorov, I; Cao, G F; Cao, J; Chan, Y L; Chang, J F; Chang, L C; Chang, Y; Chasman, C; Chen, H; Chen, Q Y; Chen, S M; Chen, X; Chen, Y X; Chen, Y; Cheng, Y P; Cherwinka, J J; Chu, M C; Cummings, J P; de Arcos, J; Deng, Z Y; Ding, Y Y; Diwan, M V; Draeger, E; Du, X F; Dwyer, D A; Edwards, W R; Ely, S R; Fu, J Y; Ge, L Q; Gill, R; Gonchar, M; Gong, G H; Gong, H; Grassi, M; Gu, W Q; Guan, M Y; Guo, X H; Hackenburg, R W; Han, G H; Hans, S; He, M; Heeger, K M; Heng, Y K; Hinrichs, P; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, L M; Hu, L J; Hu, T; Hu, W; Huang, E C; Huang, H; Huang, X T; Huber, P; Hussain, G; Isvan, Z; Jaffe, D E; Jaffke, P; Jen, K L; Jetter, S; Ji, X P; Ji, X L; Jiang, H J; Jiao, J B; Johnson, R A; Kang, L; Kettell, S H; Kramer, M; Kwan, K K; Kwok, M W; Kwok, T; Lai, W C; Lau, K; Lebanowski, L; Lee, J; Lei, R T; Leitner, R; Leung, A; Leung, J K C; Lewis, C A; Li, D J; Li, F; Li, G S; Li, Q J; Li, W D; Li, X N; Li, X Q; Li, Y F; Li, Z B; Liang, H; Lin, C J; Lin, G L; Lin, P Y; Lin, S K; Lin, Y C; Ling, J J; Link, J M; Littenberg, L; Littlejohn, B R; Liu, D W; Liu, H; Liu, J L; Liu, J C; Liu, S S; Liu, Y B; Lu, C; Lu, H Q; Luk, K B; Ma, Q M; Ma, X Y; Ma, X B; Ma, Y Q; McDonald, K T; McFarlane, M C; McKeown, R D; Meng, Y; Mitchell, I; Kebwaro, J Monari; Nakajima, Y; Napolitano, J; Naumov, D; Naumova, E; Nemchenok, I; Ngai, H Y; Ning, Z; Ochoa-Ricoux, J P; Olshevski, A; Patton, S; Pec, V; Peng, J C; Piilonen, L E; Pinsky, L; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Raper, N; Ren, B; Ren, J; Rosero, R; Roskovec, B; Ruan, X C; Shao, B B; Steiner, H; Sun, G X; Sun, J L; Tam, Y H; Tang, X; Themann, H; Tsang, K V; Tsang, R H M; Tull, C E; Tung, Y C; Viren, B; Vorobel, V; Wang, C H; Wang, L S; Wang, L Y; Wang, M; Wang, N Y; Wang, R G; Wang, W; Wang, W W; Wang, X; Wang, Y F; Wang, Z; Wang, Z M; Webber, D M; Wei, H Y; Wei, Y D; Wen, L J; Whisnant, K; White, C G; Whitehead, L; Wise, T; Wong, H L H; Wong, S C F; Worcester, E; Wu, Q; Xia, D M; Xia, J K; Xia, X; Xing, Z Z; Xu, J Y; Xu, J L; Xu, J; Xu, Y; Xue, T; Yan, J; Yang, C C; Yang, L; Yang, M S; Yang, M T; Ye, M; Yeh, M; Yeh, Y S; Young, B L; Yu, G Y; Yu, J Y; Yu, Z Y; Zang, S L; Zeng, B; Zhan, L; Zhang, C; Zhang, F H; Zhang, J W; Zhang, Q M; Zhang, Q; Zhang, S H; Zhang, Y C; Zhang, Y M; Zhang, Y H; Zhang, Y X; Zhang, Z J; Zhang, Z Y; Zhang, Z P; Zhao, J; Zhao, Q W; Zhao, Y; Zhao, Y B; Zheng, L; Zhong, W L; Zhou, L; Zhou, Z Y; Zhuang, H L; Zou, J H

    2014-01-01

    A search for light sterile neutrino mixing was performed with the first 217 days of data from the Daya Bay Reactor Antineutrino Experiment. The experiment's unique configuration of multiple baselines from six 2.9~GW$_{\\rm th}$ nuclear reactors to six antineutrino detectors deployed in two near (effective baselines 512~m and 561~m) and one far (1579~m) underground experimental halls makes it possible to test for oscillations to a fourth (sterile) neutrino in the $10^{\\rm -3}~{\\rm eV}^{2} < |\\Delta m_{41}^{2}| < 0.3~{\\rm eV}^{2}$ range. The relative spectral distortion due to electron antineutrino disappearance was found to be consistent with that of the three-flavor oscillation model. The derived limits on $\\sin^22\\theta_{14}$ cover the $10^{-3}~{\\rm eV}^{2} \\lesssim |\\Delta m^{2}_{41}| \\lesssim 0.1~{\\rm eV}^{2}$ region, which was largely unexplored.

  7. New measurement of $\\theta_{13}$ via neutron capture on hydrogen at Daya Bay

    CERN Document Server

    An, F P; Band, H R; Bishai, M; Blyth, S; Cao, D; Cao, G F; Cao, J; Cen, W R; Chan, Y L; Chang, J F; Chang, L C; Chang, Y; Chen, H S; Chen, Q Y; Chen, S M; Chen, Y X; Chen, Y; Cheng, J H; Cheng, J -H; Cheng, J; Cheng, Y P; Cheng, Z K; Cherwinka, J J; Chu, M C; Chukanov, A; Cummings, J P; de Arcos, J; Deng, Z Y; Ding, X F; Ding, Y Y; Diwan, M V; Dolgareva, M; Dove, J; Dwyer, D A; Edwards, W R; Gill, R; Gonchar, M; Gong, G H; Gong, H; Grassi, M; Gu, W Q; Guan, M Y; Guo, L; Guo, R P; Guo, X H; Guo, Z; Hackenburg, R W; Han, R; Hans, S; He, M; Heeger, K M; Heng, Y K; Higuera, A; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, T; Hu, W; Huang, E C; Huang, H X; Huang, X T; Huber, P; Huo, W; Hussain, G; Jaffe, D E; Jaffke, P; Jen, K L; Jetter, S; Ji, X P; Ji, X L; Jiao, J B; Johnson, R A; Joshi, J; Kang, L; Kettell, S H; Kohn, S; Kramer, M; Kwan, K K; Kwok, M W; Kwok, T; Langford, T J; Lau, K; Lebanowski, L; Lee, J; Lee, J H C; Lei, R T; Leitner, R; Leung, J K C; Li, C; Li, D J; Li, F; Li, G S; Li, Q J; Li, S; Li, S C; Li, W D; Li, X N; Li, Y F; Li, Z B; Liang, H; Lin, C J; Lin, G L; Lin, S; Lin, S K; Lin, Y -C; Ling, J J; Link, J M; Littenberg, L; Littlejohn, B R; Liu, D W; Liu, J J; Liu, J L; Liu, J C; Loh, C W; Lu, C; Lu, H Q; Lu, J S; Luk, K B; Lv, Z; Ma, Q M; Ma, X Y; Ma, X B; Ma, Y Q; Malyshkin, Y; Caicedo, D A Martinez; McDonald, K T; McKeown, R D; Mitchell, I; Mooney, M; Nakajima, Y; Napolitano, J; Naumov, D; Naumova, E; Ngai, H Y; Ning, Z; Ochoa-Ricoux, J P; Olshevskiy, A; Pan, H -R; Park, J; Patton, S; Pec, V; Peng, J C; Pinsky, L; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Raper, N; Ren, J; Rosero, R; Roskovec, B; Ruan, X C; Steiner, H; Sun, G X; Sun, J L; Tang, W; Taychenachev, D; Konstantin, T; Tsang, K V; Tull, C E; Viaux, N; Viren, B; Vorobel, V; Wang, C H; Wang, M; Wang, N Y; Wang, R G; Wang, W; Wang, W W; Wang, X; Wang, Y F; Wang, Z; Wang, Z M; Wei, H Y; Wen, L J; Whisnant, K; White, C G; Whitehead, L; Wise, T; Wong, H L H; Wong, S C F; Worcester, E; Wu, C -H; Wu, Q; Xia, D M; Xia, J K; Xing, Z Z; Xu, J Y; Xu, J L; Xu, J; Xu, Y; Xue, T; Yan, J; Yang, C G; Yang, H; Yang, L; Yang, M S; Yang, M T; Ye, M; Ye, Z; Yeh, M; Young, B L; Yu, G Y; Yu, Z Y; Zhan, L; Zhang, C; Zhang, H H; Zhang, J W; Zhang, Q M; Zhang, X T; Zhang, Y M; Zhang, Y X; Zhang, Z J; Zhang, Z Y; Zhang, Z P; Zhao, J; Zhao, Q W; Zhao, Y F; Zhao, Y B; Zhong, W L; Zhou, L; Zhou, N; Zhuang, H L; Zou, J H

    2016-01-01

    This article reports an improved independent measurement of neutrino mixing angle $\\theta_{13}$ at the Daya Bay Reactor Neutrino Experiment. Electron antineutrinos were identified by inverse $\\beta$-decays with the emitted neutron captured by hydrogen, yielding a data-set with principally distinct uncertainties from that with neutrons captured by gadolinium. With the final two of eight antineutrino detectors installed, this study used 621 days of data including the previously reported 217-day data set with six detectors. The dominant statistical uncertainty was reduced by 49%. Intensive studies of the cosmogenic muon-induced $^9$Li and fast neutron backgrounds and the neutron-capture energy selection efficiency, resulted in a reduction of the systematic uncertainty by 26%. The deficit in the detected number of antineutrinos at the far detectors relative to the expected number based on the near detectors yielded $\\sin^22\\theta_{13} = 0.071 \\pm 0.011$ in the three-neutrino-oscillation framework. The combination...

  8. Recent results from RENO

    Science.gov (United States)

    Park, Jungsic

    2014-06-01

    RENO (Reactor Experiment for Neutrino Oscillation) is an experiment to measure the smallest neutrino mixing angle theta θ13 using electron antineutrinos emitted from the Yonggwang (now Hanbit) nuclear power plant in Korea. Antineutrinos from six 2.8 GWth reactors are detected and compared by two detectors located at 294 m and 1384 m, respectively, from the reactor array center. Based on 402 days of data taken between 11 August 2011 and 13 October 2012, the ratio of observed to expected numbers of antineutrino at the far detector is 0.929 ± 0.006(stat.) ± 0.009(syst.). From the deficit, we determine sin22θ13 = 0.100±0.010(staṫ)±0.015(sysṫ), 5.6σ significant signal, based on a rate only analysis.

  9. Recent results from RENO

    International Nuclear Information System (INIS)

    RENO (Reactor Experiment for Neutrino Oscillation) is an experiment to measure the smallest neutrino mixing angle theta θ13 using electron antineutrinos emitted from the Yonggwang (now Hanbit) nuclear power plant in Korea. Antineutrinos from six 2.8 GWth reactors are detected and compared by two detectors located at 294 m and 1384 m, respectively, from the reactor array center. Based on 402 days of data taken between 11 August 2011 and 13 October 2012, the ratio of observed to expected numbers of antineutrino at the far detector is 0.929 ± 0.006(stat.) ± 0.009(syst.). From the deficit, we determine sin22θ13 = 0.100±0.010(stat)±0.015(syst), 5.6σ significant signal, based on a rate only analysis

  10. Getting the Most Neutrinos out of IsoDAR

    CERN Document Server

    Ciuffoli, Emilio; Mohammed, Hosam; Zhao, Fengyi; Deliyergiyev, Maksym

    2016-01-01

    Several experimental collaborations worldwide intend to test sterile neutrino models by measuring the disappearance of antineutrinos produced via isotope decay at rest (IsoDAR). The most advanced of these proposals have very similar setups, in which a proton beam strikes a target yielding neutrons which are absorbed by a high isotopic purity 7Li converter, yielding 8Li whose resulting decay yields the antineutrinos. In this note, we use FLUKA and GEANT4 simulations to investigate three proposed modifications of this standard proposal. In the first, the 7Li is replaced with 7Li compounds including a deuterium moderator. In the second, a gap is placed between the target and the converter to reduce the neutron bounce-back. Finally, we consider cooling the converter with liquid nitrogen. We find that these modifications can increase the antineutrino yield by as much as 50 percent. The first also substantially reduces the quantity of high purity 7Li which is needed.

  11. Improved Search for a Light Sterile Neutrino with the Full Configuration of the Daya Bay Experiment

    CERN Document Server

    An, F P; Band, H R; Bishai, M; Blyth, S; Cao, D; Cao, G F; Cao, J; Cen, W R; Chan, Y L; Chang, J F; Chang, L C; Chang, Y; Chen, H S; Chen, Q Y; Chen, S M; Chen, Y X; Chen, Y; Cheng, J -H; Cheng, J; Cheng, Y P; Cheng, Z K; Cherwinka, J J; Chu, M C; Chukanov, A; Cummings, J P; de Arcos, J; Deng, Z Y; Ding, X F; Ding, Y Y; Diwan, M V; Dolgareva, M; Dove, J; Dwyer, D A; Edwards, W R; Gill, R; Gonchar, M; Gong, G H; Gong, H; Grassi, M; Gu, W Q; Guan, M Y; Guo, L; Guo, R P; Guo, X H; Guo, Z; Hackenburg, R W; Han, R; Hans, S; He, M; Heeger, K M; Heng, Y K; Higuera, A; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, T; Hu, W; Huang, E C; Huang, H X; Huang, X T; Huber, P; Huo, W; Hussain, G; Jaffe, D E; Jaffke, P; Jen, K L; Jetter, S; Ji, X P; Ji, X L; Jiao, J B; Johnson, R A; Joshi, J; Kang, L; Kettell, S H; Kohn, S; Kramer, M; Kwan, K K; Kwok, M W; Kwok, T; Langford, T J; Lau, K; Lebanowski, L; Lee, J; Lee, J H C; Lei, R T; Leitner, R; Leung, J K C; Li, C; Li, D J; Li, F; Li, G S; Li, Q J; Li, S; Li, S C; Li, W D; Li, X N; Li, Y F; Li, Z B; Liang, H; Lin, C J; Lin, G L; Lin, S; Lin, S K; Lin, Y -C; Ling, J J; Link, J M; Littenberg, L; Littlejohn, B R; Liu, D W; Liu, J L; Liu, J C; Loh, C W; Lu, C; Lu, H Q; Lu, J S; Luk, K B; Lv, Z; Ma, Q M; Ma, X Y; Ma, X B; Ma, Y Q; Malyshkin, Y; Caicedo, D A Martinez; McDonald, K T; McKeown, R D; Mitchell, I; Mooney, M; Nakajima, Y; Napolitano, J; Naumov, D; Naumova, E; Ngai, H Y; Ning, Z; Ochoa-Ricoux, J P; Olshevskiy, A; Pan, H -R; Park, J; Patton, S; Pec, V; Peng, J C; Pinsky, L; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Raper, N; Ren, J; Rosero, R; Roskovec, B; Ruan, X C; Steiner, H; Sun, G X; Sun, J L; Tang, W; Taychenachev, D; Treskov, K; Tsang, K V; Tull, C E; Viaux, N; Viren, B; Vorobel, V; Wang, C H; Wang, M; Wang, N Y; Wang, R G; Wang, W; Wang, X; Wang, Y F; Wang, Z; Wang, Z; Wang, Z M; Wei, H Y; Wen, L J; Whisnant, K; White, C G; Whitehead, L; Wise, T; Wong, H L H; Wong, S C F; Worcester, E; Wu, C -H; Wu, Q; Wu, W J; Xia, D M; Xia, J K; Xing, Z Z; Xu, J Y; Xu, J L; Xu, Y; Xue, T; Yang, C G; Yang, H; Yang, L; Yang, M S; Yang, M T; Ye, M; Ye, Z; Yeh, M; Young, B L; Yu, Z Y; Zeng, S; Zhan, L; Zhang, C; Zhang, H H; Zhang, J W; Zhang, Q M; Zhang, X T; Zhang, Y M; Zhang, Y X; Zhang, Y M; Zhang, Z J; Zhang, Z Y; Zhang, Z P; Zhao, J; Zhao, Q W; Zhao, Y B; Zhong, W L; Zhou, L; Zhou, N; Zhuang, H L; Zou, J H

    2016-01-01

    This Letter reports an improved search for light sterile neutrino mixing in the electron antineutrino disappearance channel with the full configuration of the Daya Bay Reactor Neutrino Experiment. With an additional 404 days of data collected in eight antineutrino detectors, this search benefits from 3.6 times the statistics available to the previous publication, as well as from improvements in energy calibration and background reduction. A relative comparison of the rate and energy spectrum of reactor antineutrinos in the three experimental halls yields no evidence of sterile neutrino mixing in the $2\\times10^{-4}$~eV$^{2} \\lesssim |\\Delta m^{2}_{41}| \\lesssim 0.3$~eV$^{2}$ mass range. The resulting limits on $\\sin^{2}2\\theta_{14}$ are improved by approximately a factor of two over previous results and constitute the most stringent constraints to date in the $|\\Delta m^{2}_{41}| \\lesssim 0.2$ eV$^{2}$ region.

  12. SoLid: Search for Oscillation with a 6Li Detector at the BR2 research reactor

    CERN Document Server

    Michiels, Ianthe

    2016-01-01

    In the past decades, various nuclear reactor neutrino experiments have measured a deficit in the flux of antineutrinos coming from the reactor at short reactor-detector distances, when compared to theoretical calculations. One of the experiments designed to investigate this reactor antineutrino anomaly is the SoLid experiment. It uses the compact BR2 research reactor from the SCK-CEN in Mol, Belgium, to perform reactor antineutrino flux measurements at very short baseline. These proceedings discuss the general detection concepts of the SoLid experiment and its novel detector technology. The performance of the SoLid design is demonstrated with some results of the analysis of the data gathered with the experiment's first large scale test module, SM1.

  13. The first phase of the MARE project in Milano

    International Nuclear Information System (INIS)

    The international project 'Microcalorimeter Arrays for a Rhenium Experiment' (MARE) aims at the direct and calorimetric measurement of the electron anti-neutrino mass with sub-electronvolt sensitivity. The experimental strategy consists in studying the beta spectrum of 187Re near the end-point looking for the spectral distortion expected for a finite anti-neutrino mass. The MARE project has a staged approach: in the final experimental phase (MARE-2), several large arrays with as many as 10 000 detectors each will be deployed to collect the statistics required to probe the anti-neutrino mass with a sensitivity of at least 0.2 eV, comparable to the one expected for the Katrin experiment (KATRIN LoI, 2001, ). In the short term, smaller scale experiments are planned to reach sensitivities of the order of 1 eV (MARE-1). This contribution reports on the Milano group activity for the MARE project.

  14. A new MC-based method to evaluate the fission fraction uncertainty at reactor neutrino experiment

    CERN Document Server

    Ma, X B; Chen, Y X

    2016-01-01

    Uncertainties of fission fraction is an important uncertainty source for the antineutrino flux prediction in a reactor antineutrino experiment. A new MC-based method of evaluating the covariance coefficients between isotopes was proposed. It was found that the covariance coefficients will varying with reactor burnup and which may change from positive to negative because of fissioning balance effect, for example, the covariance coefficient between $^{235}$U and $^{239}$Pu changes from 0.15 to -0.13. Using the equation between fission fraction and atomic density, the consistent of uncertainty of fission fraction and the covariance matrix were obtained. The antineutrino flux uncertainty is 0.55\\% which does not vary with reactor burnup, and the new value is about 8.3\\% smaller.

  15. The Origin and Implications of the Shoulder in Reactor Neutrino Spectra

    CERN Document Server

    Hayes, A C; Garvey, G T; Ibeling, Duligur; Jungman, Gerard; Kawano, T; Mills, Robert W

    2015-01-01

    We analyze within a nuclear database framework the shoulder observed in the antineutrino spectra in current reactor experiments. We find that the ENDF/B-VII.1 database predicts that the antineutrino shoulder arises from an analogous shoulder in the aggregate fission beta spectra. In contrast, the JEFF-3.1.1 database does not predict a shoulder. We consider several possible origins of the shoulder, and find possible explanations. For example, there could be a problem with the measured aggregate beta spectra, or the harder neutron spectrum at a light-water power reactor could affect the distribution of beta-decaying isotopes. In addition to the fissile actinides, we find that $^{238}$U could also play a significant role in distorting the total antineutrino spectrum. Distinguishing these and quantifying whether there is an anomaly associated with measured reactor neutrino signals will require new short-baseline experiments, both at thermal reactors and at reactors with a sizable epithermal neutron component.

  16. LAMPF neutrino experiment to test muon number conservation

    International Nuclear Information System (INIS)

    The need for a muon number conservation law separate from lepton number conservation is mandated by the absence of neutrinoless muon-electron transitions. The form of the muon number conservation law, however, is not determined by these considerations. A search was made for electron antineutrinos coming from positive muon decays, which would be allowed by a multiplicative formulation of muon number conservation, but not by an additive formulation. The LAMPF beam dump was used as a source of positive muons decaying at rest; electron antineutrinos were detected via inverse beta decay in a six-ton water Cerenkov counter. No excess of events above known backgrounds was seen; a limit was placed on the branching ratio for positive muon decay to electron antineutrinos of R -40 cm2 is in good agreement with the calculated value of 0.48 x 10-40 cm2

  17. Neutrino and Electron-positron Pair Emission from Phase-induced Collapse of Neutron Stars to Quark Stars

    CERN Document Server

    Cheng, K S

    2010-01-01

    We study the energy released from phase-transition induced collapse of neutron stars, which results in large amplitude stellar oscillations. To model this process we use a Newtonian hydrodynamic code, with a high resolution shock-capturing scheme. The physical process considered is a sudden phase transition from normal nuclear matter to a mixed phase of quark and nuclear matter. We show that both the temperature and the density at the neutrinosphere oscillate with time. However, they are nearly 180 degree out of phase. Consequently, extremely intense, pulsating neutrino/antineutrino and leptonic pair fluxes will be emitted. During this stage several mass ejecta can be ejected from the stellar surface by the neutrinos and antineutrinos. These ejecta can be further accelerated to relativistic speeds by the electron/positron pairs, created by the neutrino and antineutrino annihilation outside the stellar surface. We suggest that this process may be a possible mechanism for short Gamma-Ray Bursts.

  18. Reactor (nu)over-bar(e) disappearance in the Double Chooz experiment

    OpenAIRE

    Abe, Y; Aberle, C.; dos Anjos, J. C.; Barriere, J.C.; Bergevin, M.; Bernstein, A; Bezerra, T. J. C.; Bezrukhov, L.; Blucher, E.; Bowden, N. S.; Buck, C.; Busenitz, J.; Cabrera, A.; Caden, E; Camilleri, L.

    2012-01-01

    The Double Chooz experiment has observed 8249 candidate electron antineutrino events in 227.93 live days with 33.71 GW-ton-years (reactor power X detector mass X live time) exposure using a 10.3 m(3) fiducial volume detector located at 1050 m from the reactor cores of the Chooz nuclear power plant in France. The expectation in case of theta(13) = 0 is 8937 events. The deficit is interpreted as evidence of electron antineutrino disappearance. From a rate plus spectral shape analysis we find si...

  19. Science & Technology Review July/August 2008

    Energy Technology Data Exchange (ETDEWEB)

    Bearinger, J P

    2008-05-27

    This months issue has the following articles: (1) Science Translated for the Greater Good--Commentary by Steven D. Liedle; (2) The New Face of Industrial Partnerships--An entrepreneurial spirit is blossoming at Lawrence Livermore; (3) Monitoring a Nuclear Weapon from the Inside--Livermore researchers are developing tiny sensors to warn of detrimental chemical and physical changes inside nuclear warheads; (4) Simulating the Biomolecular Structure of Nanometer-Size Particles--Grand Challenge simulations reveal the size and structure of nanolipoprotein particles used to study membrane proteins; and (5) Antineutrino Detectors Improve Reactor Safeguards--Antineutrino detectors track the consumption and production of fissile materials inside nuclear reactors.

  20. Neutrino geophysics with KamLAND and future prospects

    OpenAIRE

    Enomoto, S.; Ohtani, E.; Inoue, K.; Suzuki, A.

    2005-01-01

    The Kamioka liquid scintillator anti-neutrino detector (KamLAND) is a low-energy and low-background neutrino detector which could be a useful probe for determining the U and Th abundances of the Earth. We constructed a model of the Earth in order to evaluate the rate of geologically produced anti-neutrinos (geo-neutrinos) detectable by KamLAND. We found that KamLAND can be used to determine the absolute abundances of U and Th in the Earth with an accuracy sufficient for placing important cons...

  1. The Kr2Det project: Search for mass-3 state contribution |U_{e3}|^2 to the electron neutrino using a one reactor - two detector oscillation experiment at Krasnoyarsk underground site

    OpenAIRE

    Martemianov, V.; Mikaelyan, L.; Sinev, V.; Kopeikin, V.; Kozlov, Yu.

    2002-01-01

    The main physical goal of the project is to search with reactor antineutrinos for small mixing angle oscillations in the atmospheric mass parameter region around {\\Delta}m^{2}_{atm} ~ 2.5 10^{-3} eV^2 in order to find the element U_{e3} of the neutrino mixing matrix or to set a new more stringent constraint (U_{e3} is the contribution of mass-3 state to the electron neutrino flavor state). To achieve this we propose a "one reactor - two detector" experiment: two identical antineutrino spectro...

  2. Recent result from RENO

    Science.gov (United States)

    Seo, Hyunkwan; RENO Collaboration

    2016-05-01

    The Reactor Experiment for Neutrino Oscillation (RENO) started data-taking from August, 2011 and has measured the smallest neutrino mixing angle θ13 by observing the disappearance of reactor antineutrinos. Antineutrinos from the six reactors at Hanbit Nuclear Power Plant in Korea are detected and compared by the two identical detectors located in the near and far distances from the reactor array center. We present new results on precisely measured sin 22θ13 value and |Δm2 ee| based on spectral analysis using the 800 days of data sample, which are taken from August, 2011 to Dec., 2013.

  3. Time-Energy Uncertainty Relations for Neutrino Oscillation and M\\"Ossbauer Neutrino Experiment

    CERN Document Server

    Bilenky, S M; Potzel, W

    2008-01-01

    Using the Mandelstam-Tamm method we derive time-energy uncertainty relations for neutrino oscillations. We demonstrate that the small energy uncertainty of antineutrinos in a recently considered experiment with recoilless resonant (M\\"ossbauer) production and absorption of tritium antineutrinos is in conflict with the energy uncertainty which, according to the time-energy uncertainty relation, is necessary for neutrino oscillations to happen. A M\\"ossbauer neutrino experiment could provide a unique possibility to test the applicability of the time-energy uncertainty relation to neutrino oscillations and to reveal the true nature of neutrino oscillations.

  4. A new strategy for probing the Majorana neutrino CP violating phases and masses1

    International Nuclear Information System (INIS)

    We propose a new strategy for detecting the CP-violating phases and the effective mass of muon Majorana neutrinos by measuring observables associated with neutrino-antineutrino oscillations in π± decays. Within the generic framework of quantum field theory, we compute the non-factorizable probability for producing a pair of same-charged muons in π± decays as a distinctive signature of νμ-ν-barμ oscillations. Using the neutrino-antineutrino oscillation probability reported by MINOS collaboration, a new stringent bound on the effective muon-neutrino mass is derived.

  5. Reactor θ13 Results and Recent Results from FNAL Neutrino Experiments

    International Nuclear Information System (INIS)

    The past year has been very exciting for neutrino physics. The last mixing angle, θ13, has been measured by a number of experiments and is quite large. These experiments will, hopefully, continue reducing systematic and statistical errors in anticipation of statistically significant CP violation experiments. At Fermilab, MiniBooNE has finished its data run and has new results for electron antineutrino excesses; MINOS has done a combined fit for their νμ disappearance measurements for neutrinos and antineutrinos (which are now consistent) and presented results for a sterile neutrino search; and Minerνa has presented its first cross section results

  6. Geoneutrino Analysis in KamLAND: Input and Desiderata

    CERN Document Server

    Fogli, G L; Palazzo, A; Rotunno, A M

    2004-01-01

    The Kamioka Liquid scintillator Anti-Neutrino Detector (KamLAND) is collecting antineutrino events generated by nuclear reactors and by Thorium and Uranium decay in the Earth interior. We comment on a systematic approach to the evaluation of the geo-neutrino contribution and of its uncertainties in KamLAND, taking into account geophysical and geochemical indications, estimates, and data. The results can help to improve both the neutrino oscillation analysis and the knowledge of the Earth interior. Input and desiderata for future geoneutrino analyses are identified.

  7. DANSS Experiment Data Acquisition System

    OpenAIRE

    Hons, Zdenek; Vlášek, Jakub

    2016-01-01

    DANSS (Detector of the reactor AntiNeutrino based on Solid Scintillator) is a project aiming to measure a spectrum of reactor antineutrinos using inverse beta decay (IBD) in a plastic scintillator. The detector is located close to an industrial nuclear reactor core and is covered by passive and active shielding. It is expected to detect about 15000 IBD events per day. Light from the detector is sensed by PMT and SiPM. This paper describes the data acquisition system used for data readout of t...

  8. Vector and Axial Form Factors Applied to Neutrino Quasielastic Scattering

    CERN Document Server

    Budd, H; Arrington, J

    2005-01-01

    We calculate the quasielastic cross sections for neutrino scattering on nucleons using up to date fits to the nucleon elastic electromagnetic form factors GEp, GEn, GMp, GMn, and weak form factors. We show the extraction of Fa for neutrino experiments. We show how well \\minerva, a new approved experiment at FNAL, can measure Fa. We show the that Fa has a different contribution to the anti-neutrino cross section, and how the anti-neutrino data can be used to check Fa extracted from neutrino scattering.

  9. Neutrino Mixing Discriminates Geo-reactor Models

    CERN Document Server

    Dye, S T

    2009-01-01

    Geo-reactor models suggest the existence of natural nuclear reactors at different deep-earth locations with loosely defined output power. Reactor fission products undergo beta decay with the emission of electron antineutrinos, which routinely escape the earth. Neutrino mixing distorts the energy spectrum of the electron antineutrinos. Characteristics of the distorted spectrum observed at the earth's surface could specify the location of a geo-reactor, discriminating the models and facilitating more precise power measurement. The existence of a geo-reactor with known position could enable a precision measurement of the neutrino oscillation parameter delta-mass-squared.

  10. Neutrino oscillations under gravity: mass independent oscillation

    OpenAIRE

    Mukhopadhyay, Banibrata

    2003-01-01

    I discuss the possibility of neutrino oscillation in presence of gravity. In this respect I consider the propagation of neutrinos in the early phase of universe and around black holes. It is seen that whether the rest masses of a neutrino and corresponding anti-neutrino are considered to be same or not due to space-time curvature effect non-zero oscillation probability between the neutrino and anti-neutrino states comes out. Therefore I can conclude that under gravity neutrino oscillation tak...

  11. Target studies for the production of lithium8 for neutrino physics using a low energy cyclotron

    OpenAIRE

    Bungau, Adriana; Barlow, Roger; Shaevitz, Michael; Conrad, Janet; Spitz, Joshua

    2012-01-01

    Lithium 8 is a short lived beta emitter producing a high energy anti-neutrino, which is very suitable for making several measurements of fundamental quantities. It is proposed to produce Lithium 8 with a commercially available 60 MeV cyclotron using protons or alpha particles on a Beryllium 9 target. We have used the GEANT4 program to model these processes, and calculate the anti-neutrino fluxes that could be obtained in a practical system. We also calculate the production of undesirable cont...

  12. IsoDAR Neutrino Experiment Simulation with Proton and Deuteron Beams

    CERN Document Server

    Zhao, Fengyi; Han, Chengdong; Fu, Qiang; Chen, Xurong

    2015-01-01

    In this paper we consider high-intensity source of electron antineutrinos from the production and subsequent decay of 8Li. It opens a wide range of possible searches for beyond standard model physics via studies of the inverse beta decay interaction. In IsoDAR experiments Lithium 8 is a short lived beta emitter producing a high intensity anti-neutrinos, which is very suitable for making several important neutrino experiments. In this paper we used the GEANT4 program. to simulate neutrino production using proton and deuteron beams. We find that the neutrino production rate is about 3 times from deuteron beam than from proton beam in low energy region.

  13. Results and Prospects from the Daya Bay Reactor Neutrino Experiment

    CERN Document Server

    Higuera, A

    2016-01-01

    The Daya Bay reactor experiment has reported the most precise measurement of sin$^{2}2\\theta_{13}$ and $\\Delta m^{2}_{ee}$ by using a data set with the fully constructed design of 8 antineutrino detectors (ADs). We also report on a new independent measurement of sin$^{2}2\\theta_{13}$ from neutron capture on hydrogen, which confirms the results using gadolinium caputres. Several other analyses are also performed, including a measurements on the absolute reactor antineutrino flux and a search for light sterile neutrinos. Prospects for new analyses such as searching for CPT/LI violation at Daya Bay are ongoing.

  14. Data analysis in beta-spectroscopy with cryogenic detectors

    CERN Document Server

    Fontanelli, F; Gatti, F; Swift, A M; Vitale, S

    1999-01-01

    In the environment of the 'Manu' experiment for the electron anti-neutrino mass determination with microcalorimeters, we developed a full system to analyze data and extract sensible results. Here we report on data simulation and analysis. We show that, with a single detector with the energy resolution we obtained up to now (15 eV RMS) and a rate of 1 Hz, we may put an upper limit to the electron anti-neutrino mass of the order of 20 eV at 95% C.L. in three months of data taking.

  15. Supernova neutrino signals by liquid Argon detector and neutrino magnetic moment

    CERN Document Server

    Yoshida, Takashi; Kimura, Keiichi; Kawagoe, Shio; Kajino, Toshitaka; Yokomakura, Hidekazu

    2011-01-01

    We study electron-neutrino and electron-antineutrino signals from a supernova with strong magnetic field detected by a 100 kton liquid Ar detector. The change of neutrino flavors by resonant spin-flavor conversions, matter effects, and neutrino self-interactions are taken into account. Different neutrino signals, characterized by neutronization burst event and the total event numbers of electron-neutrinos and electron-antineutrinos, are expected with different neutrino oscillation parameters and neutrino magnetic moment. Observations of supernova neutrino signals by a 100 kton liquid Ar detector would constrain oscillation parameters as well as neutrino magnetic moment in either normal and inverted mass hierarchies.

  16. Geo-neutrinos

    Directory of Open Access Journals (Sweden)

    L. Ludhova

    2012-08-01

    Full Text Available Geo-neutrinos, electron anti-neutrinos produced in β-decays of naturally occurring radioactive isotopes in the Earth, are a unique direct probe of our planet's interior. After a brief introduction about the Earth (mostly for physicists and the very basics about the neutrinos and anti-neutrinos (mostly for geologists, I describe the geo-neutrinos' properties and the main aims of their study. An overview of the latest experimental results obtained by KamLand and Borexino experiments is provided. A short overview of future perspectives of this new inter-disciplinary field is given.

  17. Review article "Geo-neutrinos"

    Directory of Open Access Journals (Sweden)

    L. Ludhova

    2012-12-01

    Full Text Available Geo-neutrinos, electron anti-neutrinos produced in β-decays of naturally occurring radioactive isotopes in the Earth, are a unique direct probe of our planet's interior. After a brief introduction about the Earth (mostly for physicists and the very basics about the neutrinos and anti-neutrinos (mostly for geologists, I describe the geo-neutrino properties and the main aims of their study. An overview of the latest experimental results obtained by KamLAND and Borexino experiments is provided. A short overview of future perspectives of this new inter-disciplinary field is given.

  18. Manual Calibration System for Daya Bay Reactor Neutrino Experiment

    Institute of Scientific and Technical Information of China (English)

    HUANG; Han-xiong; RUAN; Xi-chao; REN; Jie; LV; Yin-long; FAN; Cheng-jun; CHEN; Yan-nan; WANG; Zhao-hui; ZHOU; Zu-ying; HOU; Long; ZHANG; Jia-wen; ZHANG; Yin-hong; YU; Chao-ju; HE; Wei; ZHOU; Bin

    2012-01-01

    <正>The neutrino mixing angle θ13 with a significance of 7.7 standard deviations has been published by the Daya Bay anti-neutrino experiment collaboration in 2012. To understand the non-uniformity and the energy non-linearity of the anti-neutrino detector (AD), a calibration campaign for the AD1 with the Manual Calibration System (MCS) has been finished. The aim of this calibration plan is to deploy the calibration sources to any positions inside the Inner Acrylic Vessel (IAV), to study detail properties of AD.

  19. Weak Strangeness and Eta Production

    CERN Document Server

    Alam, M Rafi; Alvarez-Ruso, Luis; Simo, I Ruiz; Vacas, M J Vicente; Singh, S K

    2013-01-01

    We have studied strange particle production off nucleons through $\\Delta S =0 $ and $|\\Delta S| = 1$ channels, and specifically single kaon/antikaon, eta, associated particle production for neutrino/antineutrino induced processes as well as antineutrino induced single hyperon production processes. We have developed a microscopical model based on the SU(3) chiral Lagrangians. The basic parameters of the model are $f_\\pi$, the pion decay constant, Cabibbo angle, the proton and neutron magnetic moments and the axial vector coupling constants for the baryons octet. For antikaon production we have also included $\\Sigma^*(1385)$ resonance and for eta production $S_{11}(1535)$ and $S_{11}(1650)$ resonances are included.

  20. Weak production of strange particles off the nucleon

    Energy Technology Data Exchange (ETDEWEB)

    Alam, M. Rafi; Athar, M. Sajjad [Department of Physics, Aligarh Muslim University, Aligarh-202 002 (India); Simo, I. Ruiz [Dipartimento di Fisica, Universitá degli Studi di Trento Via Sommarive 14, Povo (Trento) I-38123 (Italy); Alvarez-Ruso, L.; Vacas, M. J. Vicente [Departamento de Física Teórica and Instituto de Física Corpuscular, Centro Mixto Universidad de Valencia-CSIC, E-46071 Valencia (Spain)

    2015-05-15

    The strange particle production off the nucleon induced by neutrinos and antineutrinos is investigated at low and intermediate energies. We develop a microscopic model based on the SU(3) chiral Lagrangian. The studied mechanisms are the main source of single kaon production for (anti)neutrino energies up to 1.5 GeV. Using this model we have also studied the associated production of kaons and hyperons. The cross sections are large enough to be measured by experiments such as MINERνA, T2K and NOνA.

  1. Supernova SN1987A Bound on Neutrino Spectra for R-Process Nucleosynthesis

    CERN Document Server

    Horowitz, C J

    2002-01-01

    The neutrino driven wind during a core collapse supernova is an attractive site for r-process nucleosynthesis. The electron fraction $Y_e$ in the wind depends on observable neutrino energies and luminosities. The mean antineutrino energy is limited by supernova SN1987A data while lepton number conservation constrains the ratio of antineutrino to neutrino luminosities. If $Y_e$, in the wind, is to be suitable for rapid neutron capture nucleosynthesis, then the mean electron neutrino energy may be significantly lower then that predicted in present supernova simulations, or there may be new neutrino physics such as oscillations to sterile neutrinos.

  2. Exact expressions and improved approximations for interaction rates of neutrinos with free nucleons in a high-temperature, high-density gas

    Science.gov (United States)

    Schinder, Paul J.

    1990-01-01

    The exact expressions needed in the neutrino transport equations for scattering of all three flavors of neutrinos and antineutrinos off free protons and neutrons, and for electron neutrino absorption on neutrons and electron antineutrino absorption on protons, are derived under the assumption that nucleons are noninteracting particles. The standard approximations even with corrections for degeneracy, are found to be poor fits to the exact results. Improved approximations are constructed which are adequate for nondegenerate nucleons for neutrino energies from 1 to 160 MeV and temperatures from 1 to 50 MeV.

  3. Monte Carlo simulation of the Neutrino-4 experiment

    Science.gov (United States)

    Serebrov, A. P.; Fomin, A. K.; Onegin, M. S.; Ivochkin, V. G.; Matrosov, L. N.

    2015-12-01

    Monte Carlo simulation of the two-section reactor antineutrino detector of the Neutrino-4 experiment is carried out. The scintillation-type detector is based on the inverse beta-decay reaction. The antineutrino is recorded by two successive signals from the positron and the neutron. The simulation of the detector sections and the active shielding is performed. As a result of the simulation, the distributions of photomultiplier signals from the positron and the neutron are obtained. The efficiency of the detector depending on the signal recording thresholds is calculated.

  4. Monte Carlo simulation of the Neutrino-4 experiment

    Energy Technology Data Exchange (ETDEWEB)

    Serebrov, A. P., E-mail: serebrov@pnpi.spb.ru; Fomin, A. K.; Onegin, M. S.; Ivochkin, V. G.; Matrosov, L. N. [National Research Center Kurchatov Institute, Petersburg Nuclear Physics Institute (Russian Federation)

    2015-12-15

    Monte Carlo simulation of the two-section reactor antineutrino detector of the Neutrino-4 experiment is carried out. The scintillation-type detector is based on the inverse beta-decay reaction. The antineutrino is recorded by two successive signals from the positron and the neutron. The simulation of the detector sections and the active shielding is performed. As a result of the simulation, the distributions of photomultiplier signals from the positron and the neutron are obtained. The efficiency of the detector depending on the signal recording thresholds is calculated.

  5. Measurement of fission products β decay properties using a total absorption spectrometer

    Science.gov (United States)

    Zakari-Issoufou, A.-A.; Porta, A.; Fallot, M.; Algora, A.; Tain, J. L.; Valencia, E.; Rice, S.; Agramunt, J.; Äystö, J.; Bowry, M.; Bui, V. M.; Caballero-Folch, R.; Cano-Ott, D.; Eloma, V.; Estévez, E.; Farrelly, G. F.; Garcia, A.; Gelletly, W.; Gomez-Hornillos, M. B.; Gorlychev, V.; Hakala, J.; Jokinen, A.; Jordan, M. D.; Kankainen, A.; Kondev, F. G.; Martinez, T.; Mendoza, E.; Molina, F.; Moore, I.; Perez, A.; Podolyak, Zs.; Penttilä, H.; Regan, P. H.; Rissanen, J.; Rubio, B.; Weber, C.

    2013-12-01

    In a nuclear reactor, the β decay of fission fragments is at the origin of decay heat and antineutrino flux. These quantities are not well known while they are very important for reactor safety and for our understanding of neutrino physics. One reason for the discrepancies observed in the estimation of the decay heat and antineutrinos flux coming from reactors could be linked with the Pandemonium effect. New measurements have been performed at the JYFL facility of Jyväskylä with a Total Absorption Spectrometer (TAS) in order to circumvent this effect. An overview of the TAS technique and first results from the 2009 measurement campaign will be presented.

  6. Towards an axiomatic model of fundamental interactions at Planck scale

    CERN Document Server

    Kiselev, Arthemy V

    2014-01-01

    By exploring possible physical sense of notions, structures, and logic in a class of noncommutative geometries, we try to unify the four fundamental interactions within an axiomatic quantum picture. We identify the objects and algebraic operations which could properly encode the formation and structure of sub-atomic particles, antimatter, annihilation, CP-symmetry violation, mass endowment mechanism, three lepton-neutrino matchings, spin, helicity and chirality, electric charge and electromagnetism, as well as the weak and strong interaction between particles, admissible transition mechanisms (e.g., muon to muon neutrino, electron, and electron antineutrino), and decays (e.g., neutron to proton, electron, and electron antineutrino).

  7. MiniBooNE as related to Windows on the Universe

    Energy Technology Data Exchange (ETDEWEB)

    Stefanski, Ray; /Fermilab

    2009-12-01

    The measurement of absolute neutrino and anti-neutrino cross-sections, the observation of a 'low energy anomaly' in the neutrino sector, the constraints placed on the LSND effect by a non-observation of neutrino oscillations, the search for neutrino and anti-neutrino appearance, and for the possible existence of new heavy particles makes MiniBooNE a major contributor to the current view of the Universe. This paper addresses specific model constraints set by the MiniBooNE data, and explores expectations for further remaining analysis of the data.

  8. Experiment finds one in a billion

    CERN Multimedia

    Peach, Kenneth J

    1997-01-01

    The E787 collaboration has witnessed the rarest decay of a particle ever observed. Using the AGS at Brookhaven, USA, the team detected a single event caused by the decay of a positive K-meson to a possible pi-meson, a neutrino and an antineutrino (1/2 page).

  9. Calculating Pi Using the Monte Carlo Method

    Science.gov (United States)

    Williamson, Timothy

    2013-01-01

    During the summer of 2012, I had the opportunity to participate in a research experience for teachers at the center for sustainable energy at Notre Dame University (RET @ cSEND) working with Professor John LoSecco on the problem of using antineutrino detection to accurately determine the fuel makeup and operating power of nuclear reactors. During…

  10. Electron and Muon production cross-sections in quasielastic ν(ν¯)-Nucleus scattering for Eν < 1GeV

    Science.gov (United States)

    Akbar, F.; Alam, M. Rafi; Athar, M. Sajjad; Chauhan, S.; Singh, S. K.; Zaidi, F.

    2015-10-01

    In this paper, we have studied (anti)neutrino induced charged current quasielastic (CCQE) scattering from some nuclear targets in the energy region of Eν FGM) available in the literature. The results for (anti)neutrino-nucleus scattering cross-section per interacting nucleons are compared with the corresponding results in free nucleon case.

  11. Correlated background and impact on the measurement of θ13 with the Double Chooz detector

    International Nuclear Information System (INIS)

    The Double Chooz experiment uses antineutrinos emitted from the Chooz nuclear power plant (France) to measure the oscillation mixing parameter θ13. By using two detectors at different baselines, a precise measurement of antineutrinos disappearance is anticipated. The Far detector has been taking physics data since April 2011, while the Near detector is under construction. Data from April 13, 2011 to March 30, 2012 taken with the Far detector only have been analyzed and an indication for antineutrino disappearance, consistent with the current neutrino oscillation hypothesis, has been found. The best fit value for the neutrino mixing parameter sin2(2θ13) is 0.109 ± 0.030(stat.) ± 0.025(syst.). This thesis present an accurate description of the Double Chooz experiment, with particular emphasis on the Far detector and its acquisition system. The main focus of the thesis is the accurate study of the correlated background affecting the Double Chooz antineutrinos sample and its impact on the measurement of the mixing parameter θ13. A general overview of the current experimental scenario which aim to the characterization of the neutrino oscillation is also provided, focusing on the recent results obtained in this field. (author)

  12. 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.

  13. High statistics neutrino dimuon production

    CERN Document Server

    Rander, J S

    1980-01-01

    Reviews the work-in-progress on neutrino and antineutrino dimuon production studies within the CDHS collaboration. A sample of 10000 opposite sign dimuons, collected in nu and nu WBB runs at the CERN- SPS, have recently been measured and are under analysis. (10 refs).

  14. Physics of Nuclear Antishadowing

    OpenAIRE

    Schmidt, Ivan

    2005-01-01

    Shadowing and antishadowing of the electromagnetic nuclear structure functions are produced by the coherence of multiscattering quark nuclear processes. This picture leads to substantially different antishadowing for charged and neutral current processes, particularly in anti-neutrino reactions, thus affecting the extraction of the weak-mixing angle $\\sin^2\\theta_W$.

  15. Higgs-boson production together with neutrino pair at e+e- colliders

    International Nuclear Information System (INIS)

    The cross section for production of supersymmetric neutral Higgs boson in association with a neutrino-antineutrino muon pair in e+e- annihilation are calculated, i.e. e+e- → νμν-barμHi0 via different propagators. (author)

  16. New tests for neutrinos in low-energy solar experiments

    CERN Document Server

    Pastor, S

    1999-01-01

    We show how future solar neutrino experiments in the low energy region can be used to test novel neutrino properties. Information on the Majorana nature or neutrino magnetic moments can be extracted from the observation of electron anti-neutrinos from the Sun and the measurement of an azimuthal asymmetry in the total number of events, respectively.

  17. Charged current neutrino interactions below 30 GeV

    International Nuclear Information System (INIS)

    Charged current data of spark chamber neutrino experiment at 70 GeV Serpukhov accelerator (10200 events in ν beam and 3600 events in anti ν beam with energies up to 30 GeV) have been analyzed. Total neutrino and antineutrino cross sections and v-distributions are obtained

  18. Probing the Earth's interior with the LENA detector

    CERN Document Server

    Hochmuth, K A; Fields, B D; Undagoitia, T M; Oberauer, L; Potzel, W; Wurm, M; Hochmuth, Kathrin A.; Feilitzsch, Franz v.; Fields, Brian D.; Undagoitia, Teresa Marrodan; Oberauer, Lothar; Potzel, Walter; Wurm, Michael

    2006-01-01

    A future large-volume liquid scintillator detector such as the proposed 50 kton LENA (Low Energy Neutrino Astronomy) detector would provide a high-statistics measurement of terrestrial antineutrinos originating from $\\beta$-decays of the uranium and thorium chains. Additionally, the neutron is scattered in the forward direction in the detection reaction $\\bar\

  19. Light Sterile Neutrinos, Lepton Number Violating Interactions and the LSND Anomaly

    CERN Document Server

    Babu, K S; Mocioiu, Irina; Pakvasa, Sandip

    2016-01-01

    We develop the consequences of introducing a purely leptonic, lepton number violating non-standard interaction (NSI) and standard model neutrino mixing with a fourth, sterile neutrino in the analysis of short-baseline, neutrino experiments. We focus on the muon decay at rest (DAR) result from the Liquid Scintillation Neutrino Experiment (LSND) and the Karlsruhe and Rutherford Medium Energy Neutrino Experiment (KARMEN). We make a comprehensive analysis of lepton number violating, NSI effective operators and find nine that affect muon decay relevant to LSND results. Two of these preserve the standard model (SM) value 3/4 for the Michel rho and delta parameters and, overall, show favorable agreement with precision data and the electron anti-neutrino signal from LSND data. We display theoretical models that lead to these two effective operators. In the model we choose to apply to DAR data, both electron anti-neutrino appearance from muon anti-neutrino oscillation and electron anti-neutrino survival after producti...

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

    CERN Multimedia

    2002-01-01

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

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

    CERN Document Server

    Sobków, W

    2015-01-01

    In this paper, we show how a presence of the exotic scalar, tensor weak interactions in addition to the standard vector-axial (V-A) one may help to distinguish the Dirac from Majorana neutrinos in the elastic scattering of (anti)neutrino beam off the unpolarized electrons in the limit of vanishing (anti)neutrino mass. We assume that the incoming (anti)neutrino beam comes from the polarized muon decay at rest and is the left-right chiral mixture with assigned direction of the transversal spin polarization with respect to the production plane. We display that the azimuthal asymmetry in the angular distribution of recoil electrons is generated by the interference terms between the standard and exotic couplings, which are proportional to the transversal (anti)neutrino spin polarization and independent of the neutrino mass. This asymmetry for the Majorana neutrinos is distinct from the one for the Dirac neutrinos through the absence of interference between the standard and tensor couplings. Additionally, the inter...

  2. Earthquake forecast via neutrino tomography

    Institute of Scientific and Technical Information of China (English)

    WANG Bin; CHEN Ya-Zheng; LI Xue-Qian

    2011-01-01

    We discuss the possibility of forecasting earthquakes by means of (anti)neutrino tomography. An- tineutrinos emitted from reactors are used as a probe. As the antineutrinos traverse through a region prone to earthquakes, observable variations in the matter effect on the antineutrino oscillation would provide a tomog- raphy of the vicinity of the region. In this preliminary work, we adopt a simplified model for the geometrical profile and matter density in a fault zone. We calculate the survival probability of electron antineutrinos for cases without and with an anomalous accumulation of electrons which can be considered as a clear signal of the coming earthquake, at the geological region with a fault zone, and find that the variation may reach as much as 3% for ν emitted from a reactor. The case for a ν beam from a neutrino factory is also investigated, and it is noted that, because of the typically high energy associated with such neutrinos, the oscillation length is too large and the resultant variation is not practically observable. Our conclusion is that with the present reactor facilities and detection techniques, it is still a difficult task to make an earthquake forecast using such a scheme, though it seems to be possible from a theoretical point of view while ignoring some uncertainties. However, with the development of the geology, especially the knowledge about the fault zone, and with the improvement of the detection techniques, etc., there is hope that a medium-term earthquake forecast would be feasible.

  3. Charge Conjugation Violation in Supernovae and The Neutron Shortage for R-Process Nucelosynthesis

    CERN Document Server

    Horowitz, C J; Li, Gang

    2000-01-01

    Core collapse supernovae are dominated by energy transport from neutrinos. Therefore, some supernova properties could depend on symetries and features of the standard model weak interactions. The cross section for neutrino capture is larger than that for antineutrino capture by one term of order the neutrino energy over the nucleon mass. This reduces the ratio of neutrons to protons in the $\

  4. Earthquake forecast via neutrino tomography

    International Nuclear Information System (INIS)

    We discuss the possibility of forecasting earthquakes by means of (anti) neutrino tomography. Antineutrinos emitted from reactors are used as a probe. As the antineutrinos traverse through a region prone to earthquakes, observable variations in the matter effect on the antineutrino oscillation would provide a tomography of the vicinity of the region. In this preliminary work, we adopt a simplified model for the geometrical profile and matter density in a fault zone. We calculate the survival probability of electron antineutrinos for cases without and with an anomalous accumulation of electrons which can be considered as a clear signal of the coming earthquake, at the geological region with a fault zone, and find that the variation may reach as much as 3% for (anti nu)e emitted from a reactor. The case for a νe beam from a neutrino factory is also investigated, and it is noted that, because of the typically high energy associated with such neutrinos, the oscillation length is too large and the resultant variation is not practically observable. Our conclusion is that with the present reactor facilities and detection techniques, it is still a difficult task to make an earthquake forecast using such a scheme, though it seems to be possible from a theoretical point of view while ignoring some uncertainties. However, with the development of the geology, especially the knowledge about the fault zone, and with the improvement of the detection techniques, etc., there is hope that a medium-term earthquake forecast would be feasible. (authors)

  5. Some measurements for determining strangeness matrix elements in the nucleon

    Energy Technology Data Exchange (ETDEWEB)

    Henley, E.M.; Pollock, S.J.; Ying, S. [Washington Univ., Seattle, WA (United States); Frederico, T. [Centro Tecnico Aeroespacial (CTA-IEAv), Sao Jose dos Campos, SP (Brazil). Inst. de Estudos Avancados; Krein, [Universidade Estadual Paulista, Sao Paulo, SP (Brazil). Inst. de Fisica Teorica; Williams, A.G. [Florida State Univ., Tallahassee, FL (United States)

    1991-12-31

    Some experiments to measure strangeness matrix elements of the proton are proposed. Two of these suggestions are described in some detail, namely electro-production of phi mesons and the difference between neutrino and antineutrino scattering for isospin zero targets such as deuterium.

  6. Some measurements for determining strangeness matrix elements in the nucleon

    Energy Technology Data Exchange (ETDEWEB)

    Henley, E.M.; Pollock, S.J.; Ying, S. (Washington Univ., Seattle, WA (United States)); Frederico, T. (Centro Tecnico Aeroespacial (CTA-IEAv), Sao Jose dos Campos, SP (Brazil). Inst. de Estudos Avancados); Krein, (Universidade Estadual Paulista, Sao Paulo, SP (Brazil). Inst. de Fisica Teorica); Williams, A.G. (Florida State Univ., Tallahassee, FL (United States))

    1991-01-01

    Some experiments to measure strangeness matrix elements of the proton are proposed. Two of these suggestions are described in some detail, namely electro-production of phi mesons and the difference between neutrino and antineutrino scattering for isospin zero targets such as deuterium.

  7. Spin and electroweak effects in the neutrino-electron interaction

    International Nuclear Information System (INIS)

    The experimental data on elastic ν-baree- scattering with reactor antineutrinos are also analysed. νe- and ν-bare- scattering are highly sensitive to values of the EM moments of neutrinos. The results obtained give following bounds on the values of neutrino EM moments: f2ν(0), g2ν(0) -11

  8. Towards a 13 measurement

    Indian Academy of Sciences (India)

    Kam-Biu Luk

    2012-11-01

    Reactor-based antineutrino experiments hold the promise of providing an unambiguous determination of the neutrino mixing angle 13. At present, Daya Bay, Double Chooz and RENO are such experiments being set up for this purpose. In this paper, the status and prospects of these three initiatives are presented.

  9. Beta decay of fission products for the non-proliferation and decay heat of nuclear reactors

    International Nuclear Information System (INIS)

    Today, nuclear energy represents a non-negligible part of the global energy market, most likely a rolling wheel to grow in the coming decades. Reactors of the future must face the criteria including additional economic but also safety, non-proliferation, optimized fuel management and responsible management of nuclear waste. In the framework of this thesis, studies on non-proliferation of nuclear weapons are discussed in the context of research and development of a new potential tool for monitoring nuclear reactors, the detection of reactor antineutrinos, because the properties of these particles may be of interest for the International Agency of Atomic Energy (IAEA), in charge of the verification of the compliance by States with their safeguards obligations as well as on matters relating to international peace and security. The IAEA encouraged its member states to carry on a feasibility study. A first study of non-proliferation is performed with a simulation, using a proliferating scenario with a CANDU reactor and the associated antineutrinos emission. We derive a prediction of the sensitivity of an antineutrino detector of modest size for the purpose of the diversion of a significant amount of plutonium. A second study was realized as part of the Nucifer project, an antineutrino detector placed nearby the OSIRIS research reactor. The Nucifer antineutrino detector is dedicated to non-proliferation with an optimized efficiency, designed to be a demonstrator for the IAEA. The simulation of the OSIRIS reactor is developed here for calculating the emission of antineutrinos which will be compared with the data measured by the detector and also for characterizing the level of background noises emitted by the reactor detected in Nucifer. In general, the reactor antineutrinos are emitted during radioactive decay of fission products. These radioactive decays are also the cause of the decay heat emitted after the shutdown of a nuclear reactor of which the estimation is an

  10. Expected geoneutrino signal at JUNO

    Science.gov (United States)

    Strati, Virginia; Baldoncini, Marica; Callegari, Ivan; Mantovani, Fabio; McDonough, William F.; Ricci, Barbara; Xhixha, Gerti

    2015-12-01

    Constraints on the Earth's composition and on its radiogenic energy budget come from the detection of geoneutrinos. The Kamioka Liquid scintillator Antineutrino Detector (KamLAND) and Borexino experiments recently reported the geoneutrino flux, which reflects the amount and distribution of U and Th inside the Earth. The Jiangmen Underground Neutrino Observatory (JUNO) neutrino experiment, designed as a 20 kton liquid scintillator detector, will be built in an underground laboratory in South China about 53 km from the Yangjiang and Taishan nuclear power plants, each one having a planned thermal power of approximately 18 GW. Given the large detector mass and the intense reactor antineutrino flux, JUNO aims not only to collect high statistics antineutrino signals from reactors but also to address the challenge of discriminating the geoneutrino signal from the reactor background. The predicted geoneutrino signal at JUNO is terrestrial neutrino unit (TNU), based on the existing reference Earth model, with the dominant source of uncertainty coming from the modeling of the compositional variability in the local upper crust that surrounds (out to approximately 500 km) the detector. A special focus is dedicated to the 6° × 4° local crust surrounding the detector which is estimated to contribute for the 44% of the signal. On the basis of a worldwide reference model for reactor antineutrinos, the ratio between reactor antineutrino and geoneutrino signals in the geoneutrino energy window is estimated to be 0.7 considering reactors operating in year 2013 and reaches a value of 8.9 by adding the contribution of the future nuclear power plants. In order to extract useful information about the mantle's composition, a refinement of the abundance and distribution of U and Th in the local crust is required, with particular attention to the geochemical characterization of the accessible upper crust where 47% of the expected geoneutrino signal originates and this region contributes

  11. Estudo da Oscilação de Neutrinos Muônicos Usando Dados Atmosféricos e de Acelerador nos Experimentos MINOS e MINOS+

    Energy Technology Data Exchange (ETDEWEB)

    Medeiros, Michelle Mesquita de [Federal Univ. of Goiás, Goiania, GO (Brazil)

    2015-01-01

    The MINOS (Main Injector Neutrino Oscillation Search) and MINOS+ experiments were designed to study neutrino oscillations using a muon neutrino beam which is detected in two different locations, in the Near Detector and in the Far Detector. The distance between the detectors allows the beam neutrinos to oscillate to a different flavor. Therefore, a disappearance of the muon neutrinos from the beam is observed in the Far Detector. The Far Detector has a special apparatus which makes possible the selection of atmospheric neutrinos and antineutrinos. These come from interactions of cosmic rays with the Earth’s atmosphere. Both detectors have a magnetic field, allowing the distiction between neutrinos and antineutrinos interactions. This thesis presents the first combined analysis of data from the MINOS and MINOS+ experiments. We have analyzed the combined neutrino energy spectrum from the complete MINOS beam data and the first, more energetic, MINOS+ beam data. The disappearance of the muon neutrinos was observed and the data has shown to be congruent with the oscillation model. Beyond that, we have measured the atmospheric oscillation parameters of the beam and atmospheric neutrinos and antineutrinos from MINOS combined with the atmospheric neutrinos and antineutrinos from MINOS+. Assuming the same oscillation parameters for both neutrinos and antineutrinos, the best fit is obtained for inverted hierarchy and lower octant with Δm2 32 = 2:37 X 10-3 eV2 and sin2 θ 23 = 0:43, and the limits m2 32 = [2,29 - 2,49] 10-3 eV2 (68%) and sin2 θ23 = 0.36 - 0.66 (90%). These results are the most precise measurement of the neutrinos mass splitting using muon neutrino disappearance data only.

  12. Research and Development for a Gadolinium Doped Water Cherenkov Detector

    CERN Document Server

    Renshaw, Andrew

    2012-01-01

    The proposed introduction of a soluble gadolinium (Gd) compound into water Cherenkov detectors can result in a high efficiency for the detection of free neutrons capturing on the Gd. The delayed 8 MeV gamma cascades produced by these captures, in coincidence with a prompt positron signal, serve to uniquely identify electron antineutrinos interacting via inverse beta decay. Such coincidence detection can reduce backgrounds, allowing a large Gd-enhanced water Cherenkov detector to make the first observation of supernova relic neutrinos and high precision measurements of Japan's reactor antineutrino flux, while still allowing for all current physics studies to be continued. Now, a dedicated Gd test facility is operating in the Kamioka Mine. This new facility houses everything needed to successfully operate a Gd doped water Cherenkov detector. Successful running of this facility will demonstrate that adding Gd salt to SK is both safe for the detector and is capable of delivering the expected physics benefits.

  13. Improved estimate of the cross section for inverse beta decay

    CERN Document Server

    Ankowski, Artur M

    2016-01-01

    The hypothesis of the conserved vector current, relating the vector weak and isovector electromagnetic currents, plays a fundamental role in quantitative description of neutrino interactions. Despite being experimentally confirmed with great precision, it is not fully implemented in existing calculations of the cross section for inverse beta decay, the dominant mechanism of antineutrino scattering at energies below a few tens of MeV. In this article, I estimate the corresponding cross section and its uncertainty, ensuring conservation of the vector current. While converging to previous calculations at energies of several MeV, the obtained result is appreciably lower and predicts more directional positron production near the reaction threshold. These findings suggest that in the current estimate of the flux of geologically produced antineutrinos the 232Th and 238U components may be underestimated by 6.1 and 3.7%, respectively. The proposed search for light sterile neutrinos using a 144Ce--144Pr source is predi...

  14. On relativistic kinetic theory

    International Nuclear Information System (INIS)

    The principles of relativistic quantum kinetic theory are outlined. The transport equation, which the relativistic Wigner distribution function should satisfy, is explicitly given for systems of particles without internal degrees of freedom. Subsequently the linear theory, leading to linear laws for the transport processes, is developed. In particular the collision brackets are expressed in terms of collision integrals. As a characteristic example recent work on neutrino-antineutrino mixtures is reviewed. The numerical values of the transport coefficients obtained are of importance for the evolution of the universe during the lepton era, which lasted from 10-4 to 10 seconds after the hot big bang. It is found that during that era neutrinos and antineutrinos may separate in temperature fields, rather than annihilate each other. This result would constitute a first indication of how matter and antimatter may get spatially apart. (Auth.)

  15. A design outline for a Cherenkoff neutrino observatory

    CERN Document Server

    Bonvin, E

    2003-01-01

    An economical procedure to upgrade the existing Fairport water Cherenkoff detector is described. The detector will lower its energy threshold by increased photocoverage and light yield. Furthermore, by addition of a Gd salt it will become sensitive to neutrons produced by the inverse beta decay of anti-neutrinos on protons. The new detector can then take advantage of the existence of the Perry power nuclear reactor, located 12.9km away, as a large source of anti-neutrinos. The present gap in the exclusion plot of the neutrino oscillation parameters ($\\Delta m^2$ from $2\\times 10^{-4}$ to $10^{-2} eV^2$) may be explored and closed within 12-18 months of run-time. The detector will be able to observe other types of neutrino sources (Boron-8 solar, atmospheric, and supernova) with unprecedented advantages. The low threshold also will allow searching for exotic modes of proton-decay.

  16. Single neutral pion production by charged-current ν¯μ interactions on hydrocarbon at 〈Eν〉=3.6 GeV

    Directory of Open Access Journals (Sweden)

    T. Le

    2015-10-01

    Full Text Available Single neutral pion production via muon antineutrino charged-current interactions in plastic scintillator (CH is studied using the MINERvA detector exposed to the NuMI low-energy, wideband antineutrino beam at Fermilab. Measurement of this process constrains models of neutral pion production in nuclei, which is important because the neutral-current analog is a background for ν¯e appearance oscillation experiments. The differential cross sections for π0 momentum and production angle, for events with a single observed π0 and no charged pions, are presented and compared to model predictions. These results comprise the first measurement of the π0 kinematics for this process.

  17. Characterization of positronium properties in doped liquid scintillators

    Science.gov (United States)

    Consolati, G.; Franco, D.; Hans, S.; Jollet, C.; Meregaglia, A.; Perasso, S.; Tonazzo, A.; Yeh, M.

    2013-12-01

    Orthopositronium (o-Ps) formation and decay can replace the annihilation process, when a positron interacts in liquid scintillator media. The delay induced by the positronium decay represents either a potential signature for antineutrino detection, via inverse β decay, or to identify and suppress positron background, as recently demonstrated by the Borexino experiment. The formation probability and decay time of o-Ps depend strongly on the surrounding material. In this paper, we characterize the o-Ps properties in liquid scintillators as function of concentrations of gadolinium, lithium, neodymium, and tellurium dopers used by present and future neutrino experiments. In particular, gadolinium and lithium are high neutron cross section isotopes, widely used in reactor antineutrino experiments, while neodymium and tellurium are double β decay emitters, employed to investigates the Majorana neutrino nature. Future neutrino experiments may profit from the performed measurements to tune the preparation of the scintillator in order to maximize the o-Ps signature, and therefore the discrimination power.

  18. First charged current data from the CERN-Dortmund-Heidelberg-Saclay neutrino experiment

    International Nuclear Information System (INIS)

    The CDHS Collaboration has analyzed data taken in the CERN narrow-band antineutrino and neutrino beams. From 12000 antineutrino and 36000 neutrino charged current events at neutrino energies between 30 GeV and 200 GeV, we obtain the average inelasticity and the cross-section ratio sigma antisub(ν)/sigmasub(ν) as a function of neutrino energy. On the basis of these data we cannot confirm the high y anomaly observed by previous experiments at Fermilab. Instead, the measured average inelasticity in anti neutrino reactions and the ratio of charged current total cross-sections sigma anti sub(ν)/sigma%sub(ν) are compatible with no energy variation within their errors in the energy range 30+. (orig.)

  19. Uncovering the Matter-Neutrino Resonance

    CERN Document Server

    Vaananen, D

    2015-01-01

    Matter Neutrino Resonances (MNRs) can drastically modify neutrino flavor evolution in astrophysical environments and may significantly impact nucleosynthesis. Here we further investigate the underlying physics of MNR type flavor transitions. We provide generalized resonance conditions and make analytical predictions for the behavior of the system. We discuss the adiabatic evolution of these transitions, considering both Symmetric and Standard scenarios. Symmetric MNR transitions differ from Standard MNR transitions in that both neutrinos and antineutrinos can completely transform to other flavors simultaneously. We provide an example of the simplest system in which such transitions can occur with a neutrino and an antineutrino having a single energy and emission angle. We further apply linearized stability analysis to predict the location of self-induced nutation type (or bipolar) oscillations due to neutrino-neutrino interactions in the regions where MNR is ineffective. In all cases, we compare our analytica...

  20. A search for cosmogenic production of β-neutron emitting radionuclides in water

    Science.gov (United States)

    Dazeley, S.; Askins, M.; Bergevin, M.; Bernstein, A.; Bowden, N. S.; Shokair, T. M.; Jaffke, P.; Rountree, S. D.; Sweany, M.

    2016-06-01

    Here we present the first results of WATCHBOY, a water Cherenkov detector designed to measure the yield of β-neutron emitting radionuclides produced by cosmic ray muons in water. In addition to the β-neutron measurement, we also provide a first look at isolating single-β producing radionuclides following muon-induced hadronic showers as a check of the detection capabilities of WATCHBOY. The data taken over 207 live days indicates a 9Li production yield upper limit of 1.9 ×10-7μ-1g-1cm2 at ~400 m water equivalent (m.w.e.) overburden at the 90% confidence level. In this work the 9Li signal in WATCHBOY was used as a proxy for the combined search for 9Li and 8He production. This result will provide a constraint on estimates of antineutrino-like backgrounds in future water-based antineutrino detectors.

  1. GEMMA experiment: three years of the search for the neutrino magnetic moment

    CERN Document Server

    Beda, A G; Demidova, E V; Egorov, V G; Medvedev, D V; Shirchenko, M V; Starostin, A S; Vylov, Ts

    2009-01-01

    The result of the 3-year neutrino magnetic moment measurement at the Kalinin Nuclear Power Plant with the GEMMA spectrometer is presented. Antineutrino-electron scattering is investigated. A high-purity germanium detector of 1.5 kg placed at a distance of 13.9 m from the 3 GW(th) reactor core is used in the spectrometer. The antineutrino flux is 2.7E13 1/scm/s. The differential method is used to extract (nu-e) electromagnetic scattering events. The scattered electron spectra taken in 5184+6798 and 1853+1021 hours for the reactor ON and OFF periods are compared. The upper limit for the neutrino magnetic moment < 3.2E-11 Bohr magneton at 90% CL is derived from the data processing.

  2. Upper limit on the neutrino magnetic moment from three years of data from the GEMMA spectrometer

    CERN Document Server

    Beda, A G; Egorov, V G; Medvedev, D V; Pogosov, V S; Shirchenko, M V; Starostin, A S

    2010-01-01

    The result of the 3-year neutrino magnetic moment measurement at the Kalinin Nuclear Power Plant with the GEMMA spectrometer is presented. Antineutrino-electron scattering is investigated. A HPGe detector of 1.5 kg placed at a distance of 13.9 m from the 3 GW_th reactor core is used in the spectrometer. The antineutrino flux is 2.7x10^13 1/cm^2/s. The differential method is used to extract nu-e electromagnetic scattering events. The scattered electron spectra taken in 5184+6798 and 1853+1021 hours for the reactor ON and OFF periods are compared. The upper limits at 90% CL for the neutrino magnetic moment with and without atomic ionization mechanism were found to be 5.0x10^-12 and 3.2x10^-11 Bohr magnetons, respectively.

  3. Pulse shape discrimination capability of metal-loaded organic liquid scintillators for a short-baseline reactor neutrino experiment

    Science.gov (United States)

    Kim, B. R.; Han, B. Y.; Jeon, E. J.; Joo, K. K.; Kang, Jeongsoo; Khan, N.; Kim, H. J.; Kim, Hyunsoo; Kim, J. Y.; Siyeon, Kim; Kim, S. C.; Kim, Yeongduk; Ko, Y. J.; Lee, Jaison; Lee, Jeong-Yeon; Lee, J. Y.; Ma, K. J.; Park, Hyeonseo; Park, H. K.; Park, K. S.; Seo, K. M.; Seon, Gwang-Min; Yeo, I. S.; Yeo, K. M.

    2015-05-01

    A new short-baseline (SBL) reactor neutrino experiment is proposed to investigate a reactor anti-neutrino anomaly. A liquid scintillator (LS) is used to detect anti-neutrinos emitted from a Hanaro reactor, and the pulse shape discrimination (PSD) ability of the metal-loaded organic LSs is evaluated on small-scale laboratory samples. PSD can be affected by selecting different base solvents, and several of the LSs used two different organic base solvents, such as linear alkyl benzene and di-isopropylnaphthalene. For the metallic content, gadolinium (Gd) or lithium (6Li) was loaded into a home-made organic LS and into a commercially available liquid scintillation cocktail. A feasibility study was performed for the PSD using several different liquid scintillation cocktails. In this work, the preparation and the PSD characteristics of a promising candidate, which will be used in an above-ground environment, are summarized and presented.

  4. Neutrino Physics with JUNO

    CERN Document Server

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

    2015-01-01

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

  5. Self-induced conversion in dense neutrino gases: Pendulum in flavour space

    CERN Document Server

    Hannestad, S; Sigl, G; Wong, Y Y Y

    2006-01-01

    Neutrino-neutrino interactions can lead to collective flavour conversion effects in supernovae and in the early universe. We demonstrate that the case of "bipolar" oscillations, where a dense gas of neutrinos and antineutrinos in equal numbers completely converts from one flavour to another even if the mixing angle is small, is equivalent to a pendulum in flavour space. Bipolar flavour conversion corresponds to the swinging of the pendulum, which begins in an unstable upright position (the initial flavour), and passes through momentarily the vertically downward position (the other flavour) in the course of its motion. The time scale to complete one cycle of oscillation depends logarithmically on the vacuum mixing angle. Likewise, the presence of an ordinary medium can be shown analytically to contribute to a logarithmic increase in the bipolar conversion period. We further find that a more complex (and realistic) system of unequal numbers of neutrinos and antineutrinos is analogous to a spinning top subject t...

  6. A search for cosmogenic production of $\\beta$-neutron emitting radionuclides in water

    CERN Document Server

    Dazeley, S; Bergevin, M; Bernstein, A; Bowden, N S; Jaffke, P; Rountree, S D; Shokair, T M; Sweany, M

    2015-01-01

    Here we present the first results of WATCHBOY, a water Cherenkov detector designed to measure the yield of $\\beta$-neutron emitting radionuclides produced by cosmic ray muons in water. In addition to the $\\beta$-neutron measurement, we also provide a first look at isolating single-$\\beta$ producing radionuclides following showering muons as a check of the detection capabilities of WATCHBOY. The data taken over $207$ live days indicates a $^{9}$Li production yield upper limit of $1.9\\times10^{-7}\\mu^{-1}g^{-1}\\mathrm{cm}^2$ at $\\sim400$ meters water equivalent (m.w.e.) overburden at the $90\\%$ confidence level. In this work the $^{9}$Li signal in WATCHBOY was used as a proxy for the combined search for $^{9}$Li and $^{8}$He production. This result will provide a constraint on estimates of antineutrino-like backgrounds in future water-based antineutrino detectors.

  7. Neutrino Gravitational Redshift and the Electron Fraction Above Nascent Neutron Stars

    CERN Document Server

    Fuller, G M

    1996-01-01

    Neutrinos emitted from near the surface of the hot proto-neutron star produced by a supernova explosion may be subject to significant gravitational redshift at late times. Electron antineutrinos decouple deeper in the gravitational potential well of the neutron star than do the electron neutrinos, so that the electron antineutrinos experience a larger redshift effect than do the electron neutrinos. We show how this differential redshift can increase the electron fraction Ye in the neutrino-heated ejecta from the neutron star. Any r-process nucleosynthesis originating in the neutrino-heated ejecta would require a low Ye, implying that the differential redshift effect cannot be too large. In turn, this effect may allow nucleosynthesis to probe the nuclear equation of state parameters which set the neutron star radius and surface density scale height at times of order tpb = 10 to 25 s after core bounce.

  8. DANSS Experiment Data Acquisition System

    CERN Document Server

    Hons, Zdenek

    2016-01-01

    DANSS (Detector of the reactor AntiNeutrino based on Solid Scintillator) is a project aiming to measure a spectrum of reactor antineutrinos using inverse beta decay (IBD) in a plastic scintillator. The detector is located close to an industrial nuclear reactor core and is covered by passive and active shielding. It is expected to detect about 15000 IBD events per day. Light from the detector is sensed by PMT and SiPM. This paper describes the data acquisition system used for data readout of the 50 detector PMT channels and active shielding. Theoretical approach to the data acquisition is described and two possible solutions using QDCs and digitizers are discussed. Also described are the results of the DAQ performance during routine data taking operation of the detector.

  9. Monochromatic neutrinos from massive fourth generation neutrino annihilation in the Sun and Earth

    International Nuclear Information System (INIS)

    Accumulation inside the Earth and Sun of heavy (with the mass of 50 GeV) primordial neutrinos and antineutrinos of the fourth generation and their successive annihilation is considered. The minimal estimations of annihilational fluxes of monochromatic e, μ, τ neutrinos (neutrinos and antineutrinos) with the energy of 50 GeV are 4.1·10-6cm-2·s-1 from the Earth core and 1.1·10-7cm-2·s-1 from the Sun core. That makes the analysis of underground neutrino observatory data the additional source of information on the existence of massive stable 4th generation neutrino. It is shown that due to the kinetic equilibrium between the influx of the neutrinos and their annihilation the existence of new U(1)-gauge interaction of the 4th generation neutrino does not virtually influence the estimations of annihilational e-, μ-, τ-neutrino fluxes

  10. Characterization of positronium properties in doped liquid scintillators

    CERN Document Server

    Consolati, G; Hans, S; Jollet, C; Meregaglia, A; Perasso, S; Tonazzo, A; Yeh, M

    2013-01-01

    Ortho-positronium (o-Ps) formation and decay can replace the annihilation process, when positron interacts in liquid scintillator media. The delay induced by the positronium decay represents either a potential signature for anti-neutrino detection, via inverse beta decay, or to identify and suppress positron background, as recently demonstrated by the Borexino experiment. The formation probability and decay time of o-Ps depend strongly on the surrounding material. In this paper, we characterize the o-Ps properties in liquid scintillators as function of concentrations of gadolinium, lithium, neodymium, and tellurium, dopers used by present and future neutrino experiments. In particular, gadolinium and lithium are high neutron cross section isotopes, widely used in reactor anti-neutrino experiments, while neodymium and tellurium are double beta decay emitters, employed to investigates the Majorana neutrino nature. Future neutrino experiments may profit from the performed measurements to tune the preparation of ...

  11. LSND reloaded

    CERN Document Server

    Agarwalla, Sanjib K

    2010-01-01

    In view of the recent result from the anti-neutrino run of MiniBooNE, we suggest to repeat the original Liquid Scintillator Neutrino Detector (LSND) experiment using Super-Kamiokande, doped with Gadolinium, as detector. Due to the more than 100 times larger detector mass offered by Super-Kamiokande, the neutrino source requires a proton beam power of less than 300kW at a proton energy around a 1GeV. A one year run of this setup can corroborate or refute both the LSND and MiniBooNE claims at more than 5 sigma confidence level. If a signal is observed, the large size of Super-Kamiokande combined with its good ability to determine the position of an anti-neutrino event allows to establish the characteristic baseline dependence of oscillation.

  12. The Diffuse Supernova Neutrino Background

    CERN Document Server

    Beacom, John F

    2010-01-01

    The Diffuse Supernova Neutrino Background (DSNB) is the weak glow of MeV neutrinos and antineutrinos from distant core-collapse supernovae. The DSNB has not been detected yet, but the Super-Kamiokande (SK) 2003 upper limit on the electron antineutrino flux is close to predictions, now quite precise, based on astrophysical data. If SK is modified with dissolved gadolinium to reduce detector backgrounds and increase the energy range for analysis, then it should detect the DSNB at a rate of a few events per year, providing a new probe of supernova neutrino emission and the cosmic core-collapse rate. If the DSNB is not detected, then new physics will be required. Neutrino astronomy, while uniquely powerful, has proven extremely difficult -- only the Sun and the nearby Supernova 1987A have been detected to date -- so the promise of detecting new sources soon is exciting indeed.

  13. Neutrinos as Hot or Warm Dark Matter

    CERN Document Server

    Li, Y F

    2011-01-01

    Both active and sterile sub-eV neutrinos can serve for hot dark matter (DM). On the other hand, keV sterile neutrinos could be a good candidate for warm DM. The beta-decaying (e.g., H-3 and Ru-106) and EC-decaying (e.g., Ho-163) nuclei are considered as the most promising targets to capture those extremely low energy neutrinos and antineutrinos, respectively. We calculate the capture rates of relic electron neutrinos and antineutrinos against the corresponding beta-decay or EC-decay backgrounds in different flavor mixing schemes. We stress that such direct laboratory measurements of hot or warm DM might not be hopeless in the long term.

  14. Search for Sterile Neutrinos with a Radioactive Source at Daya Bay

    CERN Document Server

    Dwyer, D A; Littlejohn, B R; Vogel, P

    2011-01-01

    The far site detector complex of the Daya Bay reactor experiment is proposed as a location to search for sterile neutrinos with > eV mass. Antineutrinos from a 500 kCi 144Ce-144Pr beta-decay source (DeltaQ=2.996 MeV) would be detected by four identical 20-ton antineutrino targets. The site layout allows flexible source placement; several specific source locations are discussed. In one year, the 3+1 sterile neutrino hypothesis can be tested at essentially the full suggested range of the parameters Delta m^2_{new} and sin^22theta_{new} (90% C.L.). The backgrounds from six nuclear reactors at >1.6 km distance are shown to be manageable. Advantages of performing the experiment at the Daya Bay far site are described.

  15. Sterile neutrino analysis of reactor-neutrino oscillation

    CERN Document Server

    Kang, S K; Ko, Y; Siyeon, K

    2013-01-01

    Sterile neutrinos are one candidate to explain anomalies in neutrino oscillations. The mass-difference-driving oscillation between flavors can be probed only within specific combinations of baseline and flight energy. For a neutrino whose mass is completely unknown, it is necessary to scan all available ranges in spectrum and all accessible baselines. Here, we present four-neutrino analysis of the results announced by RENO and Daya Bay, which performed the definitive measurements of $\\theta_{13}$ based on the disappearance of the inverse-beta-decay antineutrino at km-order baselines. Our results within 3+1 scheme include the exclusion curve of $\\Delta m_{41}$ vs. $\\theta_{14}$, and the adjustment of $\\theta_{13}$ due to the contribution of $\\theta_{14}$ to the disappearance of electron antineutrinos.

  16. Neutrino oscillations in magnetically driven supernova explosions

    CERN Document Server

    Kawagoe, Shio; Kotake, Kei

    2009-01-01

    We investigate neutrino oscillations from core-collapse supernovae that produce magnetohydrodynamic (MHD) explosions. By calculating numerically the flavor conversion of neutrinos in the highly non-spherical envelope, we study how the explosion anisotropy has impacts on the emergent neutrino spectra through the Mikheyev-Smirnov-Wolfenstein effect. In the case of the inverted mass hierarcy with a relatively large theta_(13), we show that survival probabilities of electron type neutrinos and antineutrinos seen from the rotational axis of the MHD supernovae (i.e., polar direction), can be significantly different from those along the equatorial direction. The event numbers of electron type antineutrinos observed from the polar direction are predicted to show steepest decrease, reflecting the passage of the magneto-driven shock to the so-called high-resonance regions. Furthermore we point out that such a shock effect, depending on the original neutrino spectra, appears also for the low-resonance regions, which lea...

  17. A geoneutrino experiment at Homestake

    CERN Document Server

    Tolich, N; Currat, C A; Decowski, M P; Fujikawa, B K; Henning, R; Lesko, K T; Poon, A W P; Tolich, K; Wang, J

    2006-01-01

    A significant fraction of the 44TW of heat dissipation from the Earth's interior is believed to originate from the decays of terrestrial uranium and thorium. The only estimates of this radiogenic heat, which is the driving force for mantle convection, come from Earth models based on meteorites, and have large systematic errors. The detection of electron antineutrinos produced by these uranium and thorium decays would allow a more direct measure of the total uranium and thorium content, and hence radiogenic heat production in the Earth. We discuss the prospect of building an electron antineutrino detector approximately 700m^3 in size in the Homestake mine at the 4850' level. This would allow us to make a measurement of the total uranium and thorium content with a statistical error less than the systematic error from our current knowledge of neutrino oscillation parameters. It would also allow us to test the hypothesis of a naturally occurring nuclear reactor at the center of the Earth.

  18. JUNO Conceptual Design Report

    CERN Document Server

    Adam, T; An, G P; An, Q; Anfimov, N; Antonelli, V; Baldoncini, M; Baussan, E; Bellato, M; Bezrukov, L; Bick, D; Blyth, S; Brigatti, A; Brugière, T; Brugnera, R; Avanzini, M Buizza; Busto, J; Cabrera, A; Clerbaux, B; Cai, H; Cai, X; Cao, D W; Cao, G F; Cao, J; Chang, J F; Chang, Y; Chen, M M; Chen, P P; Chen, Q Y; Chen, S; Chen, S J; Chen, S M; Chen, X; Chen, Y X; Cheng, Y P; Chukanov, A; D'Angelo, D; de Kerret, H; Deng, Z; Deng, Z Y; Ding, X F; Ding, Y Y; Djurcic, Z; Dmitrievsky, S; Dolgareva, M; Dornic, D; Doroshkevich, E; Dracos, M; Drapier, O; Dusini, S; Enqvist, T; Favart, L; Fan, D H; Fang, C; Fang, J; Fang, X; Fedoseev, D; Fiorentini, G; Ford, R; Formozov, A; G, H N; Garfagnini, A; Gaudiot, G; Genster, C; Giammarchi, M; Gonchar, M; Gong, G H; Gong, H; Gonin, M; Gornushkin, Y; Grassi, M; Grewing, C; Gromov, V; Gu, M H; Guan, M Y; Guarino, V; Guo, G D; Guo, W L; Guo, X H; Göger-Neff, M; Hackspacher, P; Hagner, C; Han, R; Han, Z G; Hao, J J; He, M; Hellgartner, D; Heng, Y K; Hong, D J; Hou, S J; Hsiung, Y; Hu, B; Hu, J; Hu, S Y; Hu, T; Hu, W; Huang, H X; Huang, X T; Huang, X Z; Huo, L; Huo, W J; Ioannisian, A; Ioannisyan, D; Jeitler, M; Jen, K; Jetter, S; Ji, X D; Ji, X L; Jian, S Y; Jiang, D; Jiang, X S; Jollet, C; Kaiser, M; Kan, B W; Kang, L; Karagounis, M; Kazarian, N; Kettell, S; Korablev, D; Krasnoperov, A; Krokhaleva, S; Krumshteyn, Z; Kruth, A; Kuusiniemi, P; Lachenmaier, T; Lei, L P; Lei, R T; Lei, X C; Leitner, R; Lenz, F; Li, C; Li, F; Li, F L; Li, J X; Li, N; Li, S F; Li, T; Li, W D; Li, W G; Li, X L; Li, X M; Li, X N; Li, X Y; Li, Y; Li, Y F; Li, Z B; Liang, H; Liang, J J; Licciardi, M; Lin, G; Lin, S X; Lin, T; Lin, Y; Lippi, I; Liu, G; Liu, H; Liu, H B; Liu, J C; Liu, J L; Liu, J Y; Liu, Q; Liu, S B; Liu, S L; Liu, Y Y; Lombardi, P; Long, Y B; Lorenz, S; Lu, C; Lu, F; Lu, H Q; Lu, J B; Lu, J G; Lu, J S; Lubsandorzhiev, B; Lubsandorzhiev, S; Ludhova, L; Luo, F J; Luo, S; Lv, Z P; Lyashuk, V; Ma, Q M; Ma, S; Ma, X B; Ma, X Y; Mantovani, F; Mao, Y J; Mari, S; Mayilyan, D; Meng, G; Meregaglia, A; Meroni, E; Mezzetto, M; Min, J; Miramonti, L; Montuschi, M; Morozov, N; Mueller, T; Muralidharan, P; Naumov, D; Naumova, E; Nemchenok, I; Ning, Z; Nunokawa, H; Oberauer, L; Ochoa, P; Olshevskiy, A; Ortica, F; Pan, H; Paoloni, A; Parkalian, N; Parmeggiano, S; Pec, V; Pelliccia, N; Peng, H P; Poussot, P; Prummer, S; Qi, F Z; Qi, M; Qian, S; Qian, X H; Qiao, H; Qin, Z H; Ranucci, G; Re, A; Ren, B; Ren, J; Rezinko, T; Ricci, B; Robens, M; Romani, A; Roskovec, B; Ruan, X C; Ruan, X D; Rybnikov, A; Sadovsky, A; Saggese, P; Salamanna, G; Sawatzki, J; Schuler, J; Selyunin, A; Shi, G; Shi, J Y; Shi, Y J; Sinev, V; Sirignano, C; Smirnov, O; Soiron, M; Stahl, A; Stanco, L; Steinmann, J; Strati, V; Sun, G X; Sun, X L; Sun, Y J; Sun, Y Z; Taichenachev, D; Tang, J; Tietzsch, A; Tkachev, I; Trzaska, W H; Tung, Y; VOLPE, C; Vorobel, V; Votano, L; Wang, C; Wang, C S; Wang, G L; Wang, H X; Wang, M; Wang, R G; Wang, S G; Wang, W; Wang, W W; Wang, Y; Wang, Y F; Wang, Y Q; Wang, Z; Wang, Z G; Wang, Z M; Wang, Z Y; Wei, W; Wei, Y D; Weifels, M; Wen, L J; Wen, Y J; Wiebusch, C; Wong, C F; Wonsak, B; Wu, C; Wu, Q; Wu, Z; Wurm, M; Wurtz, J; Xi, Y F; Xia, D M; Xia, J K; Xiao, M J; Xie, Y G; Xu, J; Xu, J L; Xu, L Y; Xu, Y; Yang, Y; Yermia, F; Yan, B J; Yan, X B; Yang, C G; Yang, C W; Yang, H B; Yang, L; Yang, M T; Yang, Y J; Yang, Y Z; Yanovich, E; Yao, Y; Ye, M; Ye, X C; Yegin, U; You, Z Y; Yu, B X; Yu, C X; Yu, C Y; Yu, G Y; Yu, Z Y; Yuan, Y; Yuan, Z X; Zen, P; Zeng, S; Zeng, T X; Zhan, L; Zhang, C C; Zhang, F Y; Zhang, G Q; Zhang, H H; Zhang, J; Zhang, J B; Zhang, J W; Zhang, K; Zhang, P; Zhang, Q M; Zhang, T; Zhang, X; Zhang, X M; Zhang, Y H; Zhang, Y J; Zhang, Y M; Zhang, Y N; Zhang, Y P; Zhang, Y Y; Zhang, Z J; Zhang, Z Y; Zhao, J; Zhao, M; Zhao, T C; Zhao, Y B; Zheng, H; Zheng, M S; Zheng, X Y; Zheng, Y H; Zhong, W L; Zhou, G R; Zhou, J; Zhou, L; Zhou, N; Zhou, R; Zhou, S; Zhou, W X; Zhou, X; Zhou, Y; Zhu, H W; Zhu, K J; Zhuang, H L; Zong, L; Zou, J H; van Waasen, S

    2015-01-01

    The Jiangmen Underground Neutrino Observatory (JUNO) is proposed to determine the neutrino mass hierarchy using an underground liquid scintillator detector. It is located 53 km away from both Yangjiang and Taishan Nuclear Power Plants in Guangdong, China. The experimental hall, spanning more than 50 meters, is under a granite mountain of over 700 m overburden. Within six years of running, the detection of reactor antineutrinos from Yangjiang and Taishan Nuclear Power Plants can resolve the neutrino mass hierarchy at a confidence level of 3-4$\\sigma$. Meanwhile, the excellent energy resolution and large fiducial volume will lead to precise determination of the neutrino oscillation parameters $\\sin^2\\theta_{12}$, $\\Delta m^2_{21}$, and $|\\Delta m^2_{ee}|$ to an accuracy of better than 1%. As a multipurpose underground neutrino observatory, the JUNO detector can also observe neutrinos/antineutrinos from terrestrial and extra-terrestrial sources, including the supernova burst neutrinos, diffused supernova neutrin...

  19. The 5 MeV bump - a nuclear whodunit mystery

    CERN Document Server

    Huber, Patrick

    2016-01-01

    We perform a combined analysis of recent NEOS and Daya Bay data on the reactor antineutrino spectrum. This analysis includes approximately 1.5 million antineutrino events, which is the largest neutrino event sample analyzed to date. We use a double ratio which cancels flux model dependence and related uncertainties as well as the effects of the detector response model. We find at 3-4 standard deviation significance level, that plutonium-239 and plutonium-241 are disfavored as the single source for the the so-called 5 MeV bump. This analysis method has general applicability and in particular with higher statistics data sets will be able to shed significant light on the issue of the bump. With some caveat this also should allow to improve the sensitivity for sterile neutrino searches in NEOS.

  20. Limits on Active to Sterile Neutrino Oscillations from Disappearance Searches in the MINOS, Daya Bay, and Bugey-3 Experiments

    CERN Document Server

    Bay, The Daya; Adamson, P; An, F P; Anghel, I; Aurisano, A; Balantekin, A B; Band, H R; Barr, G; Bishai, M; Blake, A; Bock, S Blyth G J; Bogert, D; Cao, D; Cao, G F; Cao, J; Cao, S V; Carroll, T J; Castromonte, C M; Cen, W R; Chan, Y L; Chang, J F; Chang, L C; Chang, Y; Chen, H S; Chen, Q Y; Chen, R; Chen, S M; Chen, Y; Chen, Y X; Cheng, J; Cheng, J -H; Chen, Y P; Cheng, Z K; Cherwinka, J J; Childress, S; Chu, M C; Chukanov, A; Coelho, J A B; Corwin, L; Cronin-Hennessy, D; Cummings, J P; de Arcos, J; De Rijck, S; Deng, Z Y; Devan, A V; Devenish, N E; Ding, X F; Ding, Y Y; Diwan, M V; Dolgareva, M; Dove, J; Dwyer, D A; Edwards, W R; Escobar, C O; Evans, J J; Falk, E; Feldman, G J; Flanagan, W; Frohne, M V; Gabrielyan, M; Gallagher, H R; Germani, S; Gill, R; Gomes, R A; Gonchar, M; Gong, G H; Gong, H; Goodman, M C; Gouffon, P; Graf, N; Gran, R; Grassi, M; Grzelak, K; Gu, W Q; Guan, M Y; Guo, L; Guo, R P; Guo, X H; Guo, Z; Habig, A; Hackenburg, R W; Hahn, S R; Han, R; Hans, S; Hartnell, J; Hatcher, R; He, M; Heeger, K M; Heng, Y K; Higuera, A; Holin, A; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, T; Hu, W; Huang, E C; Huang, H X; Huang, J; Huang, X T; Huber, P; Huo, W; Hussain, G; Hylen, J; Irwin, G M; Isvan, Z; Jaffe, D E; Jaffke, P; James, C; Jen, K L; Jensen, D; Jetter, S; Ji, X L; Ji, X P; Jiao, J B; Johnson, R A; de Jong, J K; Joshi, J; Kafka, T; Kang, L; Kasahara, S M S; Kettell, S H; Kohn, S; Koizumi, G; Kordosky, M; Kramer, M; Kreymer, A; Kwan, 1 K K; Kwok, M W; Kwok, T; Lang, K; Langford, T J; Lau, K; Lebanowski, L; Lee, J; Lee, J H C; Lei, R T; Leitner, R; Leung, J K C; Li, C; Li, D J; Li, F; Li, G S; Li, Q J; Li, S; Li, S C; Li, W D; Li, X N; Li, Y F; Li, Z B; Liang, H; Lin, C J; Lin, G L; Lin, S; Lin, S K; Lin, Y -C; Link, J J Ling J M; Litchfield, P J; Littenberg, L; Littlejohn, B R; Liu, D W; Liu, J C; Liu, J L; Loh, C W; Lu, C; Lu, H Q; Lu, J S; Lucas, P; Luk, K B; Lv, Z; Ma, Q M; Ma, X B; Ma, X Y; Ma, Y Q; Malyshkin, Y; Mann, W A; Marshak, M L; Caicedo, D A Martinez; Mayer, N; McDonald, K T; McGivern, C; McKeown, R D; Medeiros, M M; Mehdiyev, R; Meier, J R; Messier, M D; Miller, W H; Mishra, S R; Mitchell, I; Mooney, M; Moore, C D; Mualem, L; Musser, J; Nakajima, Y; Naples, D; Napolitano, J; Naumov, D; Naumova, E; Nelson, J K; Newman, H B; Ngai, H Y; Nichol, R J; Ning, Z; Nowak, A; O'Connor, J; Ochoa-Ricoux, J P; Olshevskiy, A; Orchanian, M; R.,; Pahlka, R B; Paley, J; Pan, H -R; Park, J; Patterson, R B; Patton, S; Pawloski, G; Pec, V; Peng, J C; Perch, A; Pfutzner, M M; Phan, D D; Phan-Budd, S; Pinsky, L; Plunkett, R K; Poonthottathil, N; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Qiu, X; Radovic, A; Raper, N; Rebel, B; Ren, J; Rosenfeld, C; Rosero, R; Roskovec, B; Ruan, X C; Rubin, H A; Sail, P; Sanchez, M C; Schneps, J; Schreckenberger, A; Schreiner, P; Sharma, R; Sher, S Moed; Sousa, A; Steiner, H; Sun, G X; Sun, J L; Tagg, N; Talaga, R L; Tang, W; Taychenachev, D; Thomas, J; Thomson, M A; Timmons, X Tian A; Todd, J; Tognini, S C; Toner, R; Torretta, D; Treskov, K; Tsang, K V; Tull, C E; Tzanakos, G; Urheim, J; Vahle, P; Viaux, N; Viren, B; Vorobel, V; Wang, C H; Wang, M; Wang, N Y; Wang, R G; Wang, W; Wang, X; Wang, Y F; Wang, Z; Wang, Z M; Webb, R C; Weber, A; Wei, H Y; Wen, L J; Whisnant, K; White, C; Whitehead, L Whitehead L H; Wise, T; Wojcicki, S G; Wong, H L H; Wong, S C F; Worcester, E; Wu, C -H; Wu, Q; Wu, W J; Xia, D M; Xia, J K; Xing, Z Z; Xu, J L; Xu, J Y; Xu, Y; Xue, T; Yang, C G; Yang, H; Yang, L; Yang, M S; Yang, M T; Ye., M; Ye, Z; Yeh, M; Young, B L; Yu, Z Y; Zeng, S; Zhang, L ZhanC; Zhang, H H; Zhang, J W; Zhang, Q M; Zhang, X T; Zhang, Y M; Zhang, Y X; Zhang, Z J; Zhang, Z P; Zhang, Z Y; Zhao, J; Zhao, Q W; Zhao, Y B; Zhong, W L; Zhou, L; Zhou, N; Zhuang, H L; Zou, J H

    2016-01-01

    Searches for a light sterile neutrino have been independently performed by the MINOS and the Daya Bay experiments using the muon (anti)neutrino and electron antineutrino disappearance channels, respectively. In this Letter, results from both experiments are combined with those from the Bugey-3 reactor neutrino experiment to constrain oscillations into light sterile neutrinos. The three experiments are sensitive to complementary regions of parameter space, enabling the combined analysis to probe regions allowed by the LSND and MiniBooNE experiments in a minimally extended four-neutrino flavor framework. Stringent limits on $\\sin^2 2\\theta_{\\mu e}$ are set over six orders of magnitude in the sterile mass-squared splitting $\\Delta m^2_{41}$. The sterile-neutrino mixing phase space allowed by the LSND and MiniBooNE experiments is excluded for $\\Delta m^2_{41} < 0.8$ eV$^2$ at 95\\% C.L.

  1. KamLAND: A reactor neutrino experiment testing the solar neutrino anomaly

    International Nuclear Information System (INIS)

    KamLAND is a 1000 ton liquid scintillation detector currently under construction in the Kamioka mine in Japan. This underground site, with its large overburden of 2700 mw.e., is conveniently located at a distance of 150-210 km to several Japanese nuclear power stations. A measurement of the flux and energy spectrum of the electron anti-neutrinos, emitted by those reactors, will allow us to test the Large Mixing Angle Solution of the solar neutrino anomaly by performing a disappearance search for anti-neutrino oscillations. We will hence, for the first time, provide a completely solar model independent test of this particle physics solution of the solar neutrino problem. Data taking is expected to commence in 2001

  2. Gamow-Teller strength distributions and neutrino energy loss rates due to chromium isotopes in stellar matter

    CERN Document Server

    Nabi, Jameel-Un; Fayaz, Muhammad

    2016-01-01

    Gamow-Teller transitions in isotopes of chromium play a consequential role in the presupernova evolution of massive stars. $\\beta$-decay and electron capture rates on chromium isotopes significantly affect the time rate of change of lepton fraction ($\\dot{Y_{e}}$). Fine-tuning of this parameter is one of the key for simulating a successful supernova explosion. The (anti)neutrinos produced as a result of electron capture and $\\beta$-decay are transparent to stellar matter during presupernova phases. They carry away energy and this result in cooling the stellar core. In this paper we present the calculations of Gamow-Teller strength distributions and (anti)neutrino energy loss rates due to weak interactions on chromium isotopes of astrophysical importance. We compare our results with measured data and previous calculations wherever available.

  3. Neutrino nucleus cross sections

    CERN Document Server

    Athar, M Sajjad; Singh, S K; Vacas, M J Vicente

    2008-01-01

    We present the results of our calculation which has been performed to study the nuclear effects in the quasielastic, inelastic and deep inelastic scattering of neutrinos(antineutrinos) from nuclear targets. These calculations are done in the local density approximation. We take into account the effect of Pauli blocking, Fermi motion, Coulomb effect, renormalization of weak transition strengths in the nuclear medium in the case of the quasielastic reaction. The inelastic reaction leading to production of pions is calculated in a $\\Delta $- dominance model taking into account the renormalization of $\\Delta$ properties in the nuclear medium and the final state interaction effects of the outgoing pions with the residual nucleus. We discuss the nuclear effects in the $F_{3}^{A}(x)$ structure function in the deep inelastic neutrino(antineutrino) reaction using a relativistic framework to describe the nucleon spectral function in the nucleus.

  4. The weak mixing angle from low energy neutrino measurements: a global update

    CERN Document Server

    Canas, B C; Miranda, O G; Tortola, M; Valle, J W F

    2016-01-01

    Taking into account recent theoretical and experimental inputs on reactor fluxes we reconsider the determination of the weak mixing angle from low energy experiments. We perform a global analysis to all available neutrino-electron scattering data from reactor antineutrino experiments, obtaining sin^2(theta_W) = 0.252 \\pm 0.030. We discuss the impact of the new theoretical prediction for the neutrino spectrum, the new measurement of the reactor antineutrino spectrum by the Daya Bay collaboration, as well as the effect of radiative corrections. We also reanalyze the measurements of the nu_e-e cross section at accelerator experiments including radiative corrections. By combining reactor and accelerator data we obtain an improved determination for the weak mixing angle, sin^2(theta_W) = 0.254 \\pm 0.024.

  5. NuTeV structure function measurement

    Energy Technology Data Exchange (ETDEWEB)

    Tzanov, M.; /Pittsburgh U.

    2005-07-01

    The NuTeV experiment obtained high statistics samples of neutrino and antineutrino charged current events during the 1996-1997 Fermilab fixed target run. The experiment combines sign-selected neutrino and antineutrino beams and the upgraded CCFR iron-scintillator neutrino detector. A precision continuous calibration beam was used to determine the muon and hadron energy scales to a precision of 0.7% and 0.43% respectively. The structure functions F{sub 2}(x, Q{sup 2}) and xF{sub 3}(x, Q{sup 2}) obtained by fitting the y-dependence of the sum and the difference of the {nu} and {bar {nu}} differential cross sections are presented.

  6. Measurement of fission products β decay properties using a total absorption spectrometer

    Directory of Open Access Journals (Sweden)

    Zakari-Issoufou A.-A.

    2013-12-01

    Full Text Available In a nuclear reactor, the β decay of fission fragments is at the origin of decay heat and antineutrino flux. These quantities are not well known while they are very important for reactor safety and for our understanding of neutrino physics. One reason for the discrepancies observed in the estimation of the decay heat and antineutrinos flux coming from reactors could be linked with the Pandemonium effect. New measurements have been performed at the JYFL facility of Jyväskylä with a Total Absorption Spectrometer (TAS in order to circumvent this effect. An overview of the TAS technique and first results from the 2009 measurement campaign will be presented.

  7. Recent Borexino results and prospects for the near future

    CERN Document Server

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

    2014-01-01

    The Borexino experiment, located in the Gran Sasso National Laboratory, is an organic liquid scintillator detector conceived for the real time spectroscopy of low energy solar neutrinos. The data taking campaign phase I (2007 - 2010) has allowed the first independent measurements of 7Be, 8B and pep fluxes as well as the first measurement of anti-neutrinos from the earth. After a purification of the scintillator, Borexino is now in phase II since 2011. We review here the recent results achieved during 2013, concerning the seasonal modulation in the 7Be signal, the study of cosmogenic backgrounds and the updated measurement of geo-neutrinos. We also review the upcoming measurements from phase II data (pp, pep, CNO) and the project SOX devoted to the study of sterile neutrinos via the use of a 51Cr neutrino source and a 144Ce-144Pr antineutrino source placed in close proximity of the active material.

  8. Gamow-Teller strength distributions and neutrino energy loss rates due to chromium isotopes in stellar matter

    Science.gov (United States)

    Nabi, Jameel-Un; Shehzadi, Ramoona; Fayaz, Muhammad

    2016-03-01

    Gamow-Teller transitions in isotopes of chromium play a consequential role in the presupernova evolution of massive stars. β-decay and electron capture rates on chromium isotopes significantly affect the time rate of change of lepton fraction (dot{Ye}). Fine-tuning of this parameter is one of the key for simulating a successful supernova explosion. The (anti)neutrinos produced as a result of electron capture and β-decay are transparent to stellar matter during presupernova phases. They carry away energy and this result in cooling the stellar core. In this paper we present the calculations of Gamow-Teller strength distributions and (anti)neutrino energy loss rates due to weak interactions on chromium isotopes of astrophysical importance. We compare our results with measured data and previous calculations wherever available.

  9. Towards neutrino transport with flavor mixing in supernovae: the Liouville operator

    CERN Document Server

    Cardall, Christian Y

    2009-01-01

    The calculation of neutrino decoupling from nuclear matter requires a transport formalism capable of handling both collisions and flavor mixing. The first steps towards such a formalism are the construction of neutrino and antineutrino "distribution matrices," and a determination of the Liouville equations they satisfy in the noninteracting case. These steps are accomplished through study of a Wigner-transformed "density function," the mean value of paired neutrino quantum field operators.

  10. Development and Mass Production of a Mixture of LAB- and DIN-based Gadolinium-loaded Liquid Scintillator for the NEOS Short-baseline Neutrino Experiment

    OpenAIRE

    Kim, Ba Ro(Department of Physics, Chonnam National University, Gwangju 500-757, Republic of Korea); Han, Boyoung; Jeon, Eun-ju; Joo, Kyung Kwang; Kim, H. J.; Kim, Hyunsoo; Kim, Jinyu; Kim, Yeongduk; Ko, Youngju; Lee, Jaison; Lee, Jooyoung; Lee, Moohyun; Ma, Kyungju; Oh, Yoomin; Park, Hyangkyu

    2015-01-01

    A new experiment, which is called as NEOS (NEutrino Oscillation at Short baseline), is proposed on the site of Hanbit reactors at Yonggwang, South Korea, to investigate a reactor antineutrino anomaly. A homogeneous NEOS detector having a 1000-L target volume has been constructed and deployed at the tendon gallery ~25 m away from the reactor core. A linear alkylbenzene (LAB) is used as a main base solvent of the NEOS detector. Furthermore, a di-isopropylnaphthalene (DIN) is added to improve th...

  11. The CONNIE experiment

    CERN Document Server

    Aguilar-Arevalo, A; Bonifazi, C; Butner, M; Cancelo, G; Vazquez, A Castaneda; Vergara, B Cervantes; Chavez, C R; Da Motta, H; D'Olivo, J C; Anjos, J Dos; Estrada, J; Moroni, G Fernandez; Ford, R; Foguel, A; Torres, K P Hernandez; Izraelevitch, F; Kavner, A; Kilminster, B; Kuk, K; Lima, H P; Makler, M; Molina, J; Moreno-Granados, G; Moro, J M; Paolini, E E; Haro, M Sofo; Tiffenberg, J; Trillaud, F; Wagner, S

    2016-01-01

    The CONNIE experiment uses fully depleted, high resistivity CCDs as particle detectors in an attempt to measure for the first time the Coherent Neutrino-Nucleus Elastic Scattering of antineutrinos from a nuclear reactor with silicon nuclei.This talk, given at the XV Mexican Workshop on Particles and Fields (MWPF), discussed the potential of CONNIE to perform this measurement, the installation progress at the Angra dos Reis nuclear power plant, as well as the plans for future upgrades.

  12. Neutrino oscillation measurements with reactors

    OpenAIRE

    McKeown, R.D.

    2010-01-01

    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 current...

  13. Measuring Neutrino Oscillations with Nuclear Reactors

    OpenAIRE

    McKeown, R.D.

    2007-01-01

    Since the first direct observations of antineutrino events by Reines and Cowan in the 1950's [1], nuclear reactors have been an important tool in the study of neutrino properties. More recently, the study of neutrino oscillations has been a very active area of research. The pioneering observation of oscillations by the KamLAND experiment has provided crucial information on the neutrino mixing matrix. New experiments to study the remaining unknown mixing angle are currently under development. ...

  14. A Second Detector Focusing on the Second Oscillation Maximum at an Off-axis Location to Enhance the Mass Hierarchy Discovery Potential in LBNE10

    OpenAIRE

    Qian, X.; Ling, J. J.; McKeown, R.D.; Wang, W.; Worcester, E.; Zhang, C.

    2013-01-01

    The Long Baseline Neutrino Oscillation Experiment (LBNE) is proposed to determine the neutrino mass hierarchy and measure the CP phase in the leptonic sector. The current design of LBNE Phase I consists of a 10 kt liquid argon time projection chamber (LBNE10). The neutrino-antineutrino asymmetry in the electron-neutrino appearance probability has contributions from both the CP phase and the matter effect. For this reason, experimental sensitivity to the mass hierarchy depends both on the true...

  15. A Conserved Vector Current test using low energy beta-beams

    OpenAIRE

    Balantekin, A. B.; de Jesus, J. H.; Lazauskas, R.; Volpe, C.

    2006-01-01

    We discuss the possibility of testing the weak currents and, in particular, the weak magnetism term through the measurement of the electron anti-neutrinos capture by protons at a low energy beta-beam facility. We analyze the sensitivity using both the total number of events and the angular distribution of the positrons emitted in a water Cerenkov detector. We show that the weak magnetism form factor might be determined with better than several percent accuracy using the angular distribution. ...

  16. A search for flavor-changing non-standard neutrino interactions by MINOS

    CERN Document Server

    Adamson, P; Bishai, M; Blake, A; Bock, G J; Bogert, D; Cao, S V; Cherdack, D; Childress, S; Coelho, J A B; Corwin, L; Cronin-Hennessy, D; de Jong, J K; Devan, A V; Devenish, N E; Diwan, M V; Escobar, C O; Evans, J J; Falk, E; Feldman, G J; Frohne, M V; Gallagher, H R; Gomes, R A; Goodman, M C; Gouffon, P; Graf, N; Gran, R; Grzelak, K; Habig, A; Hartnell, J; Hatcher, R; Himmel, A; Holin, A; Hylen, J; Irwin, G M; Isvan, Z; James, C; Jensen, D; Kafka, T; Kasahara, S M S; Koizumi, G; Kordosky, M; Kreymer, A; Lang, K; Ling, J; Litchfield, P J; Lucas, P; Mann, W A; Marshak, M L; Mathis, M; Mayer, N; Medeiros, M M; Mehdiyev, R; Meier, J R; Messier, M D; Miller, W H; Mishra, S R; Sher, S Moed; Moore, C D; Mualem, L; Mufson, S; Musser, J; Naples, D; Nelson, J K; Newman, H B; Nichol, R J; Nowak, J A; Oliver, W P; Orchanian, M; Pahlka, R B; Paley, J; Patterson, R B; Pawloski, G; Phan-Budd, S; Plunkett, R K; Qiu, X; Radovic, A; Rebel, B; Rosenfeld, C; Rubin, H A; Sanchez, M C; Schneps, J; Schreckenberger, A; Schreiner, P; Sharma, R; Sousa, A; Tagg, N; Talaga, R L; Thomas, J; Thomson, M A; Toner, R; Torretta, D; Tzanakos, G; Urheim, J; Vahle, P; Viren, B; Weber, A; Webb, R C; White, C; Whitehead, L; Wojcicki, S G; Zwaska, R

    2013-01-01

    We report new constraints on flavor-changing non-standard neutrino interactions (NSI) using data from the MINOS experiment. We analyzed a combined set of beam neutrino and antineutrino data, and found no evidence for deviations from standard neutrino mixing. The observed energy spectra constrain the NSI parameter to the range $-0.20 < \\varepsilon_{\\mu\\tau} < 0.07\\;\\text{(90% C.L.)}$

  17. The action of neutrino ponderomotive force on supernova dynamics

    OpenAIRE

    Esposito, S.

    1999-01-01

    Collective interactions of a beam of neutrinos/antineutrinos traversing a dense magnetized plasma of electrons/positrons, protons and neutrons are studied with particular reference to the case of a Supernova. We find that the ponderomotive force exerted by neutrinos gives, contrary to expectations, a negligible contribution to the revival of the shock for a successful Supernova explosion, although new types of convection and plasma cooling processes induced by the ponderomotive force could be...

  18. Theory of Neutrino-Atom Collisions: The History, Present Status, and BSM Physics

    International Nuclear Information System (INIS)

    An overview of the current theoretical studies on neutrino-atom scattering processes is presented. The ionization channel of these processes, which is studied in experiments searching for neutrino magnetic moments, is brought into focus. Recent developments in the theory of atomic ionization by impact of reactor antineutrinos are discussed. It is shown that the stepping approximation is well applicable for the data analysis practically down to the ionization threshold

  19. The dark-matter world: Are there dark-matter galaxies?

    OpenAIRE

    Hwang, W-Y. Pauchy

    2011-01-01

    We attempt to answer whether neutrinos and antineutrinos, such as those in the cosmic neutrino background, would clusterize among themselves or even with other dark-matter particles, under certain time span, say 1 Gyr. With neutrino masses in place, the similarity with the ordinary matter increases and so is our confidence for neutrino clustering if time is long enough. In particular, the clusterings could happen with some seeds (cf. see the text for definition), the chance in the dark-matter...

  20. Qualification Tests of 474 Photomultiplier Tubes for the Inner Detector of the Double Chooz Experiment

    OpenAIRE

    Bauer, C; Borger, E.; Hofacker , R.; Jänner, K.; Kaether, F.; Langbrandtner, C.; Lindner, M.; Lucht, S.; Reissfelder, M.; Schoenert, S.; Stüken, A.; Wiebusch, C.

    2011-01-01

    The hemispherical 10" photomultiplier tube (PMT) R7081 from Hamamatsu Photonics K.K. (HPK) is used in various experiments in particle and astroparticle physics. We describe the test and calibration of 474 PMTs for the reactor antineutrino experiment Double Chooz. The unique test setup at Max-Planck-Institut f\\"ur Kernphysik Heidelberg (MPIK) allows one to calibrate 30 PMTs simultaneously and to characterize the single photo electron response, transit time spread, linear behaviour and saturati...