Science.gov

Sample records for 7be solar neutrino

  1. High precision 7Be solar neutrinos measurement and day night effect obtained with Borexino

    NASA Astrophysics Data System (ADS)

    Testera, G.; Bellini, G.; Benziger, J.; Bick, D.; Bonetti, S.; Bonfini, G.; Caccianiga, B.; Cadonati, L.; Calaprice, F.; Carraro, C.; Chavarria, A.; D'Angelo, D.; Derbin, A.; Etenko, A.; Fomenko, K.; Franco, D.; Galbiati, C.; Gazzana, S.; Ghiano, C.; Giammarchi, M.; Göger-Neff, M.; Goretti, A.; Grandi, L.; Guardincerri, E.; Hardy, S.; Ianni, Aldo; Ianni, Andrea; Korablev, D.; Kobychev, V.; Korga, G.; Koshio, Y.; Kryn, D.; Laubenstein, M.; Leung, M.; Lewke, T.; Litvinovich, E.; Loer, B.; Lombardi, P.; Lombardi, F.; Ludhova, L.; Machulin, I.; Manecki, S.; Maneschg, W.; Manuzio, G.; Meindl, Q.; Meroni, E.; Miramonti, L.; Misiaszek, M.; Montanari, D.; Mosteiro, P.; Muratova, V.; Oberauer, L.; Obolensky, M.; Ortica, F.; Pallavicini, M.; Papp, L.; Pena-Garay, C.; Perasso, L.; Perasso, S.; Pocar, A.; Raghavan, R. S.; Ranucci, G.; Razeto, A.; Romani, A.; Sabelnikov, A.; Saldanha, R.; Salvo, C.; Schönert, S.; Simgen, H.; Skorokhvatov, M.; Smirnov, O.; Sotnikov, A.; Sukhotin, S.; Suvorov, Y.; Tartaglia, R.; Vignaud, D.; Vogelaar, R. B.; von Feilitzsch, F.; Winter, J.; Wojcik, M.; Wurm, M.; Zaimidoroga, O.; Zavatarelli, S.; Zuzel, G.

    2012-11-01

    We report the direct measurement of the 7Be solar neutrino signal rate performed with the Borexino detector at the Laboratori Nazionali del Gran Sasso and the search for a day-night asymmetry of this interaction rate. The interaction rate of the 0.862 MeV 7Be neutrinos is 46±1.6(stat)-1.6+1.5(syst) counts/(day · 100 ton). The hypothesis of no oscillation for this solar neutrinos is inconsistent with our measurement at the 5.8σ C.L. Our result is the first direct measurement of solar neutrinos with an accuracy better than 5%. We report the survival probability for solar νe in the transition region between matter-enhanced and vacuum-driven oscillations. The measured day night asymmetry is Adn=0.001±0.012 (stat)±0.007 (syst), in agreement with the predicition of MSW-LMA neutrino [13] oscillations. This result discourages MSW oscillations with mixing parameters in the LOW region at more than 8.5σ, meaning that this region is, for the first time, strongly rejected without the assumption of CPT symmetry. The result can also be used to constrain some neutrino oscillation scenarios involving new physics.

  2. Absence of a day-night asymmetry in the 7Be solar neutrino rate in Borexino

    NASA Astrophysics Data System (ADS)

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

    2012-01-01

    We report the result of a search for a day-night asymmetry in the 7Be solar neutrino interaction rate in the Borexino detector at the Laboratori Nazionali del Gran Sasso (LNGS) in Italy. The measured asymmetry is Adn = 0.001 ± 0.012 (stat) ± 0.007 (syst), in agreement with the prediction of MSW-LMA solution for neutrino oscillations. This result disfavors MSW oscillations with mixing parameters in the LOW region at more than 8.5 σ. This region is, for the first time, strongly disfavored without the use of reactor anti-neutrino data and therefore the assumption of CPT symmetry. The result can also be used to constrain some neutrino oscillation scenarios involving new physics.

  3. Development of InP solid state detector and liquid scintillator containing metal complex for measurement of pp/7Be solar neutrinos and neutrinoless double beta decay

    NASA Astrophysics Data System (ADS)

    Fukuda, Yoshiyuki; Moriyama, Shigetaka

    2012-07-01

    A large volume solid state detector using a semi-insulating Indium Phosphide (InP) wafer have been developed for measurement of pp/7Be solar neutrinos. Basic performance such as the charge collection efficiency and the energy resolution were measured by 60% and 20%, respectively. In order to detect two gammas (115keV and 497keV) from neutrino capture, we have designed hybrid detector which consist InP detector and liquid xenon scintillator for IPNOS experiment. New InP detector with thin electrode (Cr 50Å- Au 50Å). For another possibility, an organic liquid scintillator containing indium complex and zirconium complex were studied for a measurement of low energy solar neutrinos and neutrinosless double beta decay, respectively. Benzonitrile was chosen as a solvent because of good solubility for the quinolinolato complexes (2 wt%) and of good light yield for the scintillation induced by gamma-ray irradiation. The photo-luminescence emission spectra of InQ3 and ZrQ4 in benzonitrile was measured and liquid scintillator cocktail using InQ3 and ZrQ4 (50mg) in benzonitrile solutions (20 mL) with secondary scintillators with PPO (100mg) and POPOP (10mg) was made. The energy spectra of incident gammas were measured, and they are first results of the gamma-ray energy spectra using luminescent of metal complexes.

  4. Solar Neutrinos

    DOE R&D Accomplishments Database

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

    1964-12-01

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

  5. Solar Neutrino Problem

    DOE R&D Accomplishments Database

    Davis, R. Jr.; Evans, J. C.; Cleveland, B. T.

    1978-04-28

    A summary of the results of the Brookhaven solar neutrino experiment is given and discussed in relation to solar model calculations. A review is given of the merits of various new solar neutrino detectors that were proposed.

  6. Solar neutrino detection

    SciTech Connect

    Miramonti, Lino

    2009-04-30

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

  7. Neutrino decay and solar neutrino seasonal effect

    NASA Astrophysics Data System (ADS)

    Picoreti, R.; Guzzo, M. M.; de Holanda, P. C.; Peres, O. L. G.

    2016-10-01

    We consider the possibility of solar neutrino decay as a sub-leading effect on their propagation between production and detection. Using current oscillation data, we set a new lower bound to the ν2 neutrino lifetime at τ2 /m2 ≥ 7.2 ×10-4s .eV-1 at 99% C.L. Also, we show how seasonal variations in the solar neutrino data can give interesting additional information about neutrino lifetime.

  8. Astroparticle physics with solar neutrinos

    PubMed Central

    NAKAHATA, Masayuki

    2011-01-01

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

  9. Astroparticle physics with solar neutrinos.

    PubMed

    Nakahata, Masayuki

    2011-01-01

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

  10. Solar Neutrino Physics

    SciTech Connect

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

    1999-07-15

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

  11. Solar neutrino with Borexino: Results and perspectives

    NASA Astrophysics Data System (ADS)

    Smirnov, O.; Bellini, G.; Benziger, J.; Bick, D.; Bonfini, G.; Bravo, D.; Caccianiga, B.; 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.; Fiorentini, G.; Galbiati, C.; Gazzana, S.; Ghiano, C.; Giammarchi, M.; Göger-Neff, M.; Goretti, A.; 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.; Mantovani, F.; Marcocci, S.; Meindl, Q.; Meroni, E.; Meyer, M.; Miramonti, L.; Misiaszek, M.; Mosteiro, P.; Muratova, V.; Oberauer, L.; Obolensky, M.; Ortica, F.; Otis, K.; Pallavicini, M.; Papp, L.; Perasso, L.; Pocar, A.; Ranucci, G.; Razeto, A.; Re, A.; Ricci, B.; Romani, A.; Rossi, N.; Saldanha, R.; Salvo, C.; Schönert, S.; Simgen, H.; Skorokhvatov, M.; 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.

    2015-03-01

    Borexino is a unique detector able to perform measurement of solar neutrinos fluxes in the energy region around 1 MeV or below due to its low level of radioactive background. It was constructed at the LNGS underground laboratory with a goal of solar 7Be neutrino flux measurement with 5% precision. The goal has been successfully achieved marking the end of the first stage of the experiment. A number of other important measurements of solar neutrino fluxes have been performed during the first stage. Recently the collaboration conducted successful liquid scintillator repurification campaign aiming to reduce main contaminants in the sub-MeV energy range. With the new levels of radiopurity Borexino can improve existing and challenge a number of new measurements including: improvement of the results on the Solar and terrestrial neutrino fluxes measurements; measurement of pp and CNO solar neutrino fluxes; search for non-standard interactions of neutrino; study of the neutrino oscillations on the short baseline with an artificial neutrino source (search for sterile neutrino) in context of SOX project.

  12. Solar Neutrinos. II. Experimental

    DOE R&D Accomplishments Database

    Davis, Raymond Jr.

    1964-01-01

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

  13. Experimental data on solar neutrinos

    NASA Astrophysics Data System (ADS)

    Ludhova, Livia

    2016-04-01

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

  14. Report of the Solar and Atmospheric Neutrino Working Group

    SciTech Connect

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

    2004-10-22

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

  15. Oscillations of solar atmosphere neutrinos

    SciTech Connect

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

    2006-11-01

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

  16. Solar Neutrinos, SNO and SNOLAB

    NASA Astrophysics Data System (ADS)

    McDonald, A. B.

    2007-06-01

    The Sudbury Neutrino Observatory has completed operation in its third phase with an array of neutron detectors in 1000 tonnes of heavy water and Cherenkov light detection 2 km underground in INCO's Creighton mine near Sudbury, Ontario, Canada. Data from the third phase is now being analyzed. In the first two phases of the project reported previously, the neutral current reaction on deuterium was used to determine the total flux of active neutrinos and the charged current reaction on deuterium provided a measure of the flux and energy spectrum of solar electron neutrinos. The flux of electron neutrinos was found to be only about one third of the total flux, providing clear evidence of neutrino flavour change. The total flux of active neutrinos was found to be in agreement with solar model calculations. The underground laboratory is being expanded to create an international facility known as SNOLAB that will be completed at the end of 2007. Proposed future experiments for the detection of lower energy solar neutrinos, geo-neutrinos, dark matter and double beta decay are described.

  17. Report on solar neutrino experiments

    SciTech Connect

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

    1984-01-01

    A summary is given of the status of solar neutrino research that includes results of the Brookhaven chlorine detector, a discussion of the development of the gallium, bromine, and lithium radiochemical detectors, and some proposals for direct counting detectors. The gallium and bromine radiochemical detectors are developed and are capable of giving critical information of interest about neutrino physics and the fusion reactions in the interior of the sun. A plan for building these detectors is outlined and a rough cost estimate is given. A review is given of the plans in the Soviet Union in solar neutrino research.

  18. Status of solar neutrino experiments

    SciTech Connect

    Beier, E.W.; Davis, R. Jr.; Kim, S.B. . Dept. of Physics); Elliott, S.R. ); Jelley, N. )

    1990-01-01

    A summary of the status of four solar neutrino experiments is presented. The Homestake {sup 37}Cl data are presented and the possible time dependence of the data is addressed. Data from 1040 days of operation of the Kamiokande II detector are presented next. The status of the {sup 71}Ga experiment in the Baksan Neutrino Observatory, which has operated for a short time, is discussed. The summary concludes with a discussion of the status of the Sudbury Neutrino Observatory, which has been under construction since the beginning of 1990. 7 refs., 6 figs.

  19. Solar mass-varying neutrino oscillations.

    PubMed

    Barger, V; Huber, Patrick; Marfatia, Danny

    2005-11-18

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

  20. Status of the Borexino Solar Neutrino Experiment, 2006

    SciTech Connect

    McCarty, Kevin B.

    2006-11-17

    The Borexino experiment is designed to measure the flux of 7Be solar neutrinos. The experiment, having a 100-ton fiducial volume of organic liquid scintillator, should detect roughly 35 neutrinos per day in the energy range 250 - 1300 keV, a range lower than that of any previous real-time neutrino detector. Though the 862-keV 7Be neutrinos make up roughly 10% of the total solar neutrino flux, they have not previously been directly observed. Their energy is at a delicate point for confirmation of the vacuum-to-matter oscillation transition. In these proceedings, I will present the status of the Borexino experiment as of August 2006, as we prepare for final filling of the detector.

  1. Solar photons, phonons and neutrinos

    NASA Astrophysics Data System (ADS)

    Chitre, S. M.

    1998-06-01

    The inside of the Sun is not directly accessible to observations. Nonetheless, it is possible to construct a reasonable picture of its interior with the help of the theory of stellar structure along with the input physics describing a multitude of processes occurring inside the Sun. In order to check the validity of these theoretical models there have been valiant attempts to measure the flux of neutrinos generated in the Sun's energy-generating core. The solar neutrino event rates reported by all the experiments to date have been consistently lower than those predicted by standard solar models. There is now a complementary probe, furnished by the accurately measured helioseismic data which provides stringent constraints on the physical conditions prevailing inside the Sun. It turns out that the helioseismically inferred density and sound speed profiles throughout the Sun's internal layers are close to those obtained with a standard solar model. A cooler solar core is, therefore, not a viable solution to account for the deficit in the measured neutrino fluxes. This leads one to the unavoidable conclusion that the solution to the solar neutrino puzzle should be sought in the realm of particle physics.

  2. The impact of Borexino on the solar and neutrino physics

    NASA Astrophysics Data System (ADS)

    Bellini, Gianpaolo

    2016-07-01

    The Borexino detector is characterized by a very low background level due to an unprecedented radio-purity, which allows to study the entire spectrum of solar neutrinos from very low energies (∼150 keV). The solar neutrino rates from pp, 7Be, pep, 8B (with a threshold down to 3 MeV) and a stringent limit of the CNO cycle rate have been already measured. In addition evidences of a null day/night asymmetry and of the solar neutrino flux seasonal variation have been reached. The contribution provided until now by Borexino in understanding the neutrino oscillation phenomenon concerns the first evidence of the oscillation in vacuum and the determination of the νe survival probability in vacuum: these results validate the paradigmatic MSW model in the vacuum regime. The Borexino results are also in good agreement with the Standard Solar Model predictions, but the metallicity puzzle is still unsolved. In addition the pp flux measured by Borexino shows a good agreement with the Solar luminosity. Evidence of geo-neutrinos has been also obtained at the level of 5.9σ C.L. Borexino is still taking data in order to: upgrade the precision of the solar neutrino rates already measured, increase the sensitivity to the neutrino flux from the CNO cycle and hopefully measure it (very challenging), and test the existence of very short base-line neutrino oscillations.

  3. Precision Solar Neutrino Measurements with the Sudbury Neutrino Observatory

    SciTech Connect

    Oblath, Noah

    2007-10-26

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

  4. Variations in the Solar Neutrino Flux

    DOE R&D Accomplishments Database

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

    1987-08-02

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

  5. John Bahcall and the Solar Neutrino Problem

    NASA Astrophysics Data System (ADS)

    Bahcall, Neta

    2016-03-01

    ``I feel like dancing'', cheered John Bahcall upon hearing the exciting news from the SNO experiment in 2001. The results confirmed, with remarkable accuracy, John's 40-year effort to predict the rate of neutrinos from the Sun based on sophisticated Solar models. What began in 1962 by John Bahcall and Ray Davis as a pioneering project to test and confirm how the Sun shines, quickly turned into a four-decade-long mystery of the `Solar Neutrino Problem': John's models predicted a higher rate of neutrinos than detected by Davis and follow-up experiments. Was the theory of the Sun wrong? Were John's calculations in error? Were the neutrino experiments wrong? John worked tirelessly to understand the physics behind the Solar Neutrino Problem; he led the efforts to greatly increase the accurately of the solar model, to understand its seismology and neutrino fluxes, to use the neutrino fluxes as a test for new physics, and to advocate for important new experiments. It slowly became clear that none of the then discussed possibilities --- error in the Solar model or neutrino experiments --- was the culprit. The SNO results revealed that John's calculations, and hence the theory of the Solar model, have been correct all along. Comparison of the data with John's theory demanded new physics --- neutrino oscillations. The Solar Neutrino saga is one of the most amazing scientific stories of the century: exploring a simple question of `How the Sun Shines?' led to the discovery of new physics. John's theoretical calculations are an integral part of this journey; they provide the foundation for the Solar Neutrino Problem, for confirming how the Sun shines, and for the need of neutrino oscillations. His tenacious persistence, dedication, enthusiasm and love for the project, and his leadership and advocacy of neutrino physics over many decades are a remarkable story of scientific triumph. I know John is smiling today.

  6. Update of GALLEX solar neutrino results and implications

    SciTech Connect

    Kirsten, T.

    1995-01-01

    The galliumchloride detector operated by the GALLEX-collaboration in the Gran Sasso Underground Laboratory responds primarily to pp-neutrinos. They are produced in the primary fusion reaction of hydrogen into deuterium and directly coupled to the solar luminosity. Standard Solar Models predict ca. 58% of the total signal expected in GALLEX (123-132 SNU) to be due to pp-neutrinos. The relative pp-neutrino dominance becomes even larger if the deficit of higher energy neutrinos (as observed in the Homestake- and Kamiokande experiments) is considered. During the first data taking period, 15 solar runs had been performed within the exposure period 14.5.1991 - 29.4.1992. The result, 81 {+-} 17 {+-} 9 SNU provided the first experimental evidence for pp-neutrinos from the Sun. At the same time, it confirmed the depression of higher energy neutrino fluxes relative to the model predictions. Here the authors report the results of 15 more solar neutrino runs, covering the period 19.8.92 - 13.10.93. They obtain 78 {+-} 13 {+-} 5 SNU. Evaluated together, the result for all 30 runs is 79 {+-} 10 {+-} 6 SNU. While the SNU rate of GALLEX I is well reproduced the statistical error has been reduced so substantially that a value of signal +2{sigma} is required to accommodate not only pp-and pep- but also the {sup 7}Be-neutrino induced {sup 71}Ge-production. Contrary, the fate of {sup 8}B-neutrinos has only little discernible effect on the GALLEX data. In conclusion, with the present errors GALLEX constitutes a 2.5 {sigma} problem for {sup 7}Be neutrinos within the frame of {open_quotes}astrophysical{close_quotes} solutions. Alternatively, the particle physics solution (MSW-effect) can consistently explain all available solar neutrino results, leading to a most probable mass scale with the muon-neutrino at approximately 3 meV (milli-eV). However, since the GALLEX result allows the presence of pp and pep neutrinos at full strength. the latter explanation of the data is not forced.

  7. Calibration of the solar neutrino detectors

    NASA Astrophysics Data System (ADS)

    Caccianiga, Barbara; Re, Alessandra Carlotta

    2016-04-01

    Calibrations have been crucial for the success of solar neutrino experiments. In this contribution we review the calibration strategies adopted by different solar neutrino experiments. In particular, we will emphasize their common critical aspects and their main differences. In order to do so, we will schematically divide the solar neutrino experiments in two groups: those based on radiochemical techniques, i.e. Homestake, Gallex/GNO, SAGE and those based on real-time techniques i.e. Kamiokande, Super-Kamiokande, SNO, Borexino and KamLAND.

  8. The status of the solar neutrino problem

    SciTech Connect

    Bowles, T.J.

    1993-12-01

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

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

    NASA Astrophysics Data System (ADS)

    Wittich, Peter

    2000-12-01

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

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

    DOE Data Explorer

    SAGE Collaboration

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

  11. Solar oscillation frequency and solar neutrino predictions

    SciTech Connect

    Cox, A.N.

    1990-07-05

    The light and velocity variations of the Sun and solar-like stars are unique among intrinsic variable stars. Unlike all other standard classes, such as Cepheids, B stars, and white dwarfs, the pulsation driving is caused by coupling with the acoustic noise in the upper convection zone. Each global pulsation mode is just another degree of freedom for the turbulent convection, and energy is shared equally between these g{sup {minus}}-modes and the solar oscillation modes. This driving and damping, together with the normal stellar pulsation mechanisms produce extremely low amplitude solar oscillations. Actually, the surface layer radiative damping is strong, and the varying oscillation mode amplitudes manifest the stochastic convection driving and the steady damping. Thus stability calculations for solar-like pulsations are difficult and mostly inconclusive, but calculations of pulsation periods are as straightforward as for all the other classes of intrinsic variable stars. The issue that is important for the Sun is its internal structure, because the mass, radius, and luminosity are extremely well known. Conventionally, we need the pulsation constants for each of millions of modes. Unknown parameters for constructing solar models are the composition and its material pressure, energy, and opacity, as well as the convection mixing length. We treat the nuclear energy and neutrino production formulas as sufficiently well known. The presence of weakly interacting massive particles (WIMPs) orbiting the solar center affects the predicted oscillation frequencies so that they do not agree with observations as well as those for models without WIMPs. 34 refs., 4 figs.

  12. Solar core homology, solar neutrinos and helioseismology

    SciTech Connect

    Bludman, S.A.; Kennedy, D.C.

    1995-12-31

    Precise numerical standard solar models (SSMs) now agree with one another and with helioseismological observations in the convective and outer radiative zones. Nevertheless these models obscure how luminosity, neutrino production and g-mode core helioseismology depend on such inputs as opacity and nuclear cross sections. Although the Sun is not homologous, its inner core by itself is chemically evolved and almost homologous, because of its compactness, radiative energy transport, and ppI-dominated luminosity production. We apply luminosity-fixed homology transformations to the core to estimate theoretical uncertainties in the SSM and to obtain a broad class of non-SSMs, parameterized by central temperature and density and purely radiative energy transport in the core. 25 refs., 3 figs., 3 tabs.

  13. Solar neutrinos, solar flares, solar activity cycle and the proton decay

    NASA Technical Reports Server (NTRS)

    Raychaudhuri, P.

    1985-01-01

    It is shown that there may be a correlation between the galactic cosmic rays and the solar neutrino data, but it appears that the neutrino flux which may be generated during the large solar cosmic ray events cannot in any way effect the solar neutrino data in Davis experiment. Only initial stage of mixing between the solar core and solar outer layers after the sunspot maximum in the solar activity cycle can explain the higher (run number 27 and 71) of solar neutrino data in Davis experiment. But solar flare induced atmospheric neutrino flux may have effect in the nucleon decay detector on the underground. The neutrino flux from solar cosmic rays may be a useful guide to understand the background of nucleon decay, magnetic monopole search, and the detection of neutrino flux in sea water experiment.

  14. Detecting Solar Neutrino Flares and Flavors

    NASA Astrophysics Data System (ADS)

    Fargion, D.

    2004-06-01

    Most power-full solar flare as the ones occurred on 23th February 1956, September 29th 1989 and recent ones occurred on 28th October, on 2nd-4th and 13th November 2003 have been respectively recorded by Radio-X- and Cosmic Rays detectors. These flares took place most in the open or in the edge and in the hidden solar disk (as for the September 29th, 1989 beyond 105Wo and for last November 2003 flare events). The 4th November event was the most powerful X event in the highest known rank category X28. The observed and estimated total flare energy E = 1031-1033 erg should be a source also of a prompt secondary neutrino burst originated, by proton-proton-pion production on the sun itself; a more delayed and spread neutrino flux signal arise later on the terrestrial atmosphere. These first earliest prompt solar neutrino burst might be already recorde, in a few neutrino clustered events, in largest neutrino underground detectors as Super-Kamiokande one, in time correlation with the sharp X-Radio flare onset. Our first estimate at the Super-Kamiokande II Laboratory is found to be a few (1-5) events. Their discover (or absence) should constrains the solar flare acceleration, energetic and its inner environment. Any large neutrino flare event might even verify the expected neutrino flavour mixing leading to comparable electron- muon event as well as a comparable energy fluence and spectra. Rare Tau appearence by neutrino muon into tau conversion might also arise.

  15. Everything under the Sun: A review of solar neutrinos

    SciTech Connect

    Gann, Gabriel D. Orebi

    2015-07-15

    Solar neutrinos offer a unique opportunity to study the interaction of neutrinos with matter, a sensitive search for potential new physics effects, and a probe of solar structure and solar system formation. This paper describes the broad physics program addressed by solar neutrino studies, presents the current suite of experiments programs, and describes several potential future detectors that could address the open questions in this field. This paper is a summary of a talk presented at the Neutrino 2014 conference in Boston.

  16. Everything under the sun: A review of solar neutrinos

    DOE PAGES

    Gann, Gabriel D. Orebi

    2015-07-15

    Solar neutrinos offer a unique opportunity to study the interaction of neutrinos with matter, a sensitive search for potential new physics effects, and a probe of solar structure and solar system formation. This paper describes the broad physics program addressed by solar neutrino studies, presents the current suite of experiments programs, and describes several potential future detectors that could address the open questions in this field. This paper is a summary of a talk presented at the Neutrino 2014 conference in Boston.

  17. Solar neutrino detection in a large volume double-phase liquid argon experiment

    NASA Astrophysics Data System (ADS)

    Franco, D.; Giganti, C.; Agnes, P.; Agostino, L.; Bottino, B.; Canci, N.; Davini, S.; De Cecco, S.; Fan, A.; Fiorillo, G.; Galbiati, C.; Goretti, A. M.; Hungerford, E. V.; Ianni, Al.; Ianni, An.; Jollet, C.; Marini, L.; Martoff, C. J.; Meregaglia, A.; Pagani, L.; Pallavicini, M.; Pantic, E.; Pocar, A.; Razeti, M.; Renshaw, A. L.; Rossi, B.; Rossi, N.; Suvorov, Y.; Testera, G.; Tonazzo, A.; Wang, H.; Zavatarelli, S.

    2016-08-01

    Precision measurements of solar neutrinos emitted by specific nuclear reaction chains in the Sun are of great interest for developing an improved understanding of star formation and evolution. Given the expected neutrino fluxes and known detection reactions, such measurements require detectors capable of collecting neutrino-electron scattering data in exposures on the order of 1 ktonne-yr, with good energy resolution and extremely low background. Two-phase liquid argon time projection chambers (LAr TPCs) are under development for direct Dark Matter WIMP searches, which possess very large sensitive mass, high scintillation light yield, good energy resolution, and good spatial resolution in all three cartesian directions. While enabling Dark Matter searches with sensitivity extending to the ``neutrino floor'' (given by the rate of nuclear recoil events from solar neutrino coherent scattering), such detectors could also enable precision measurements of solar neutrino fluxes using the neutrino-electron elastic scattering events. Modeling results are presented for the cosmogenic and radiogenic backgrounds affecting solar neutrino detection in a 300 tonne (100 tonne fiducial) LAr TPC operating at LNGS depth (3,800 meters of water equivalent). The results show that such a detector could measure the CNO neutrino rate with ~15% precision, and significantly improve the precision of the 7Be and pep neutrino rates compared to the currently available results from the Borexino organic liquid scintillator detector.

  18. Report on solar-neutrino experiments

    SciTech Connect

    Davis, R. Jr.

    1982-01-01

    This report on solar neutrino experiments will include a summary of the results of the chlorine detector, and an account of our plans to build a gallium solar neutrino experiment. In addition to discussing the experimental side of the solar neutrino problem I would like to relate our experiences during the last 15 years in working in the Homestake Gold Mine. In the course of our work at Homestake a number of independent groups have asked to use our facilities and, because of the cooperative and helpful attitude of the Mine management, these experimentalists could be easily accommodated. A brief account of these experiences may be useful for the main business of this workshop, building large particle detectors for observing nucleon decay, and the related question of the need for a national underground physics facility.

  19. Solar neutrinos, Martian rivers, and Praesepe.

    NASA Technical Reports Server (NTRS)

    Sagan, C.; Young, A. T.

    1973-01-01

    Some recent papers on solar neutrinos, Martian rivers, and Praesepe stars are reviewed. Possible causes of solar neutrino detection rates being below theoretical expectations are quoted. The widespread presence of sinuous dendritic channels on Mars is noted. The occurrence of earth-like epochs on Mars is indicated as a plausible explanation for many such channels in terms of surface liquid water flows. The roughly uniform distribution of the Praesepe stars through the main sequence width is viewed as the indication that the excursion time off the main sequence is comparable to the time between mixings.

  20. Radiochemical Solar Neutrino Experiments - Successful and Otherwise.

    SciTech Connect

    Hahn,R.L.

    2008-05-25

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

  1. Asymptotic normalization coefficients (nuclear vertex constants) for p + 7Be → 8B and the direct 7Be( p, γ)8B astrophysical S factors at solar energies

    NASA Astrophysics Data System (ADS)

    Igamov, S. B.; Yarmukhamedov, R.

    2008-10-01

    A new analysis of the precise experimental astrophysical S factors for the direct-capture reaction 7Be( p, γ)8B [A.J. Junghans et al., Phys. Rev. C 68, 065803 (2003) and L.T. Baby et al., Phys. Rev. C 67, 065805 (2003)] is carried out on the basis of a modified two-body potential approach in which the direct astrophysical S factor, S 17( E), is expressed in terms of the asymptotic normalization constants for p + 7Be → 8B and two additional conditions are involved to verify the peripheral character of the reaction under consideration. The Woods-Saxon potential form is used for the bound-( p + 7Be)-state wave function and for p 7Be-scattering wave function. New estimates are obtained for the “indirectly measured” values of the asymptotic normalization constants (the nuclear vertex constants) for the p + 7Be → 8B and S 17( E) at E ≤ 115 keV, including E = 0. These values of S 17( E) and asymptotic normalization constants have been used for obtaining the indirectly measured values of the s-wave average scattering length and the p-wave effective-range parameters for p 7Be scattering.

  2. Solar neutrino physics in the nineties

    SciTech Connect

    Wilkerson, J.F.

    1990-12-31

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

  3. Solar Neutrino flare detection in Hyperkamiokande and SK

    NASA Astrophysics Data System (ADS)

    Fargion, Daniele

    2016-07-01

    The possible buid and near activity of a Megaton neutrino detection in HyperKamiokande and the older SK implementation by Gadolinium liqid might open to future detection of largest solar flare (pion trace at tens MeV) electron neutrino and antineutrino. The multiwave detection of X-gamma and neutrino event might offer a deep view of such solar acelleration and of neutrino flavor mix along its flight. The possoble near future discover of such events will open a third neutrino astronomy windows after rarest SN 1987A and persistent Solar nuclear signals.

  4. Report on the Brookhaven Solar Neutrino Experiment

    DOE R&D Accomplishments Database

    Davis, R. Jr.; Evans, J. C. Jr.

    1976-09-22

    This report is intended as a brief statement of the recent developments and results of the Brookhaven Solar Neutrino Experiment communicated through Professor G. Kocharov to the Leningrad conference on active processes on the sun and the solar neutrino problem. The report summarizes the results of experiments performed over a period of 6 years, from April 1970 to January 1976. Neutrino detection depends upon the neutrino capture reaction /sup 37/Cl(..nu..,e/sup -/)/sup 37/Ar producing the isotope /sup 37/Ar (half life of 35 days). The detector contains 3.8 x 10/sup 5/ liters of C/sub 2/Cl/sub 4/ (2.2 x 10/sup 30/ atoms of /sup 37/Cl) and is located at a depth of 4400 meters of water equivalent (m.w.e.) in the Homestake Gold Mine at Lead, South Dakota, U.S.A. The procedures for extracting /sup 37/Ar and the counting techniques used were described in previous reports. The entire recovered argon sample was counted in a small gas proportional counter. Argon-37 decay events were characterized by the energy of the Auger electrons emitted following the electron capture decay and by the rise-time of the pulse. Counting measurements were continued for a period sufficiently long to observe the decay of /sup 37/Ar.

  5. Analysis of the influence of solar activity and atmospheric factors on 7Be air concentration by seasonal-trend decomposition

    NASA Astrophysics Data System (ADS)

    Bas, M. C.; Ortiz, J.; Ballesteros, L.; Martorell, S.

    2016-11-01

    7Be air concentrations were measured at the Universitat Politècnica de Valencia campus (in the east of Spain) during the period 2007-2014. The mean values of monthly 7Be concentrations ranged from 2.65 to 8.11 mBq/m3, showing significant intra and interannual variability. A seasonal-trend decomposition methodology was applied to identify the trend-cycle, seasonal and irregular components of the 7Be time series. The decomposition model makes it possible to estimate the influence of solar activity and atmospheric factors on the independent components, in order to find the different sources of 7Be variability. The results show that solar activity is a factor with a high inverse influence on the trend-cycle pattern of 7Be variability. Solar radiation, temperature and relative humidity are positive influential factors on the seasonal 7Be variation with a regular pattern over the years. Finally, the irregular component presents a significant negative correlation with precipitation and wind speed parameters, which have an irregular behavior over the years and seasons.

  6. The solar neutrino problem: mixing of neutrinos and mixing in the Sun.

    NASA Astrophysics Data System (ADS)

    Haxton, W. C.

    The author reviews the current status of the solar neutrino problem, including the exciting possibility of matter enhanced neutrino oscillations. Neutrino flux measurements, independent of questions of solar dynamics, appear to leave only one competing candidate astrophysical solution, at least in the case of steady state solar models. That possibility - mixing of the solar core on time scales of 3He equilibration - appears to have some attractive features. A "score card" is presented in which the two alternatives - mixed neutrinos or a mixed Sun - are handicapped.

  7. The solar neutrino problem: Mixing of neutrinos and mixing in the sun

    NASA Astrophysics Data System (ADS)

    Haxton, W. C.

    I review the current status of the solar neutrino problem, including the exciting possibility of matter enhanced neutrino oscillations. Neutrino flux measurements, independent of questions of solar dynamics, appear to leave only one competing candidate astrophysical solution, at least in the case of steady-state solar models. That possibility - mixing of the solar core on time scales of 3He equilibration - appears to have some attractive features. A “score card” is presented in which the two alternatives - mixed neutrinos or a mixed sun - are handicapped.

  8. A 17 keV neutrino and large magnetic moment solution of the solar neutrino puzzle

    NASA Astrophysics Data System (ADS)

    Akhmedov, E. Kh.; Senjanovic, G.; Tao, Zhijian; Berezhiani, Z. G.

    1992-08-01

    Zee-type models with Majorons naturally incorporate the 17 keV neutrino but in their minimal version fail to simultaneously solve the solar neutrino puzzle. If there is a sterile neutrino state, a particularly simple solution is found to the solar neutrino problem, which besides nu(sub 17) predicts a light Zeldovich-Konopinski-Mahmoud neutrino nu(sub light) = nu(sub e) + nu(sub mu)(sup c) with a magnetic moment being easily as large as 10(exp -11)(mu)(sub B) through the Barr-Freire-Zee mechanism.

  9. 17 keV neutrino and large magnetic moment solution of the solar neutrino puzzle

    NASA Astrophysics Data System (ADS)

    Akhmedov, Eugeni Kh.; Berezhiani, Zurab G.; Senjanović, Goran; Tao, Zhijian

    1993-01-01

    Zee-type models with majorons naturally incorporate the 17 keV neutrino but in their minimal version fail to simultaneously solve the solar neutrino puzzle. If there is a sterile neutrino state, we find a particularly simple solution to the solar neutrino problem, which besides ν17 predicts a light Zeldovich-Konopinski-Mahmoud neutrino νlight = νe + νcμ with a magnetic moment being easily as large as 10 -11μB through the Barr-Freire-Zee mechanism.

  10. Constraints on neutrino oscillations using 1258 days of Super-Kamiokande solar neutrino data.

    PubMed

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

    2001-06-18

    We report the result of a search for neutrino oscillations using precise measurements of the recoil electron energy spectrum and zenith angle variations of the solar neutrino flux from 1258 days of neutrino-electron scattering data in Super-Kamiokande. The absence of significant zenith angle variation and spectrum distortion places strong constraints on neutrino mixing and mass difference in a flux-independent way. Using the Super-Kamiokande flux measurement in addition, two allowed regions at large mixing are found.

  11. Feasibility of /sup 81/Br(nu,e/sup -/)/sup 81/Kr solar neutrino experiment

    SciTech Connect

    Hurst, G.S.; Allman, S.L.; Chen, C.H.; Kramer, S.D.; Thomson, J.O.; Cleveland, B.

    1985-05-01

    Several ingenious solutions have been offered for the solar neutrino problem - a defect in the solar model, the appearance of a new type of neutrino physics, the sun is no longer burning, etc. The range of these proffered solutions stresses the need for a new experiment to study the sun. The modern pulsed laser now makes possible a new solar neutrino test which examines an independent neutrino source in the sun. A recently proposed experiment would use the reaction /sup 81/Br(nu,e/sup -/)/sup 81/Kr to measure the flux of /sup 7/Be neutrinos from the sun. When /sup 7/Be decays by electron capture to make /sup 7/Li, a neutrino is emitted at 0.862 MeV and the flux of these on the earth is about 4 x 10/sup 9/ cm/sup -2/ s/sup -1/, according to the standard model. Therefore, an experiment based on /sup 81/Br(nu,e/sup -/)/sup 81/Kr which is sensitive to these lower energy neutrinos would be of fundamental importance. To first order, the chlorine experiment detects the /sup 8/B neutrinos while bromine detects the much more abundant /sup 7/Be neutrino source. In practice, the proposed bromine experiment would be very similar to the chlorine radiochemical experiment, except that /sup 81/Kr with a half-life of 2 x 10/sup 5/ years cannot be counted by decay methods. With an experiment of about the same volume as the chlorine experiment (380 m/sup 3/) filled with CH/sub 2/Br/sub 2/, the model predicts about 2 atoms of /sup 81/Kr per day. The bromine experiment depends entirely on the RIS method, implemented with pulsed lasers, for its success. 10 refs., 3 figs.

  12. Towards the resolution of the solar neutrino problem

    SciTech Connect

    Friedland, Alexander

    2000-08-29

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

  13. The analysis of solar models: Neutrinos and oscillations

    NASA Technical Reports Server (NTRS)

    Ulrich, R. K.; Rhodes, E. J., Jr.; Tomczyk, S.; Dumont, P. J.; Brunish, W. M.

    1983-01-01

    Tests of solar neutrino flux and solar oscillation frequencies were used to assess standard stellar structure theory. Standard and non-standard solar models are enumerated and discussed. The field of solar seismology, wherein the solar interior is studied from the measurement of solar oscillations, is introduced.

  14. Solar neutrino experiments and a test for neutrino oscillations with radioactive sources

    SciTech Connect

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

    1980-01-01

    The results of the Brookhaven solar neutrino experiment are given and compared to the most recent standard solar model calculations. The observations are about a factor of 4 below theoretical expectations. In view of the uncertainties involved in the theoretical models of the sun, the discrepancy is not considered to be evidence for neutrino oscillations. The status of the development of a gallium solar neutrino detector is described. Radiochemical neutrino detectors can be used to search for ..nu../sub e/ oscillations by using megacurie sources of monoenergetic neutrinos like /sup 65/Zn. A quantitative evaluation of possible experiments using the Brookhaven chlorine solar neutrino detector and a gallium detector is given. 6 figures, 3 tables.

  15. Possible explanation of the solar-neutrino puzzle

    NASA Technical Reports Server (NTRS)

    Bethe, H. A.

    1986-01-01

    A new derivation of the Mikheyev and Smirnov (1985) mechanism for the conversion of electron neutrinos into mu neutrinos when traversing the sun is presented, and various hypotheses set forth. It is assumed that this process is responsible for the detection of fewer solar neutrinos than expected, with neutrinos below a minimum energy, E(m), being undetectable. E(m) is found to be about 6 MeV, and the difference of the squares of the respective neutrino masses is calculated to be 6 X 10 to the - 5th sq eV. A restriction on the neutrino mixing angle is assumed such that the change of density near the crossing point is adiabatic. It is predicted that no resonance conversion of neutrinos will occur in the dense core of supernovae, but conversion of electron neutrinos to mu neutrinos will occur as they escape outward through a density region around 100.

  16. Detecting Solar Neutrino Flare in Megaton and km3 detectors

    NASA Astrophysics Data System (ADS)

    Fargion, Daniele; di Giacomo, Paola

    2009-03-01

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

  17. Solar neutrino physics with low-threshold dark matter detectors

    NASA Astrophysics Data System (ADS)

    Billard, J.; Strigari, L. E.; Figueroa-Feliciano, E.

    2015-05-01

    Dark matter detectors will soon be sensitive to Solar neutrinos via two distinct channels: coherent neutrino-nucleus and neutrino-electron elastic scatterings. We establish an analysis method for extracting Solar model properties and neutrino properties from these measurements, including the possible effects of sterile neutrinos which have been hinted at by some reactor experiments and cosmological measurements. Even including sterile neutrinos, through the coherent scattering channel, a 1 ton-year exposure with a low-threshold background free Germanium detector could improve on the current measurement of the normalization of the B 8 Solar neutrino flux down to 3% or less. Combining with the neutrino-electron elastic scattering data will provide constraints on both the high- and low-energy survival probability and will improve on the uncertainty on the active-to-sterile mixing angle by a factor of 2. This sensitivity to active-to-sterile transitions is competitive and complementary to forthcoming dedicated short baseline sterile neutrino searches with nuclear decays. Finally, we show that such solar neutrino physics potentials can be reached as long as the signal-to-noise ratio is better than 0.1.

  18. Solar neutrinos: Prospects for detection and implications

    NASA Astrophysics Data System (ADS)

    Haxton, W. C.

    From the viewpoint of particle physics, the Sun provides us with a high intensity (approx. 10(11)/cm(2)sec) source of neutrinos that have traveled over an interesting distance. An opportunity to mount incomparable neutrino oscillation experiments would be missed if not exploited. From the distribution, a precise record of the thermonuclear reactions that occur in the sun's high-temperature core. A unique, quantitative test of theories of stellar evolution is provided, and thus one of the fundamental clocks that monitor the aging of the universe. This information cannot be obtained from conventional observations of the radiation emitted from cool stellar surfaces: solar photons have lost, in their 10(7) year journey outward from the core, all detailed memory of the mechanisms by which they were created. The feasibility, by virtue of several very recent advances in nuclear physics and nuclear chemistry, of a complete program of solor neutrino spectroscopy that will quantitatively test both the standard stellar model and the behavior of low-energy netrinos over astrophysical distances is examined.

  19. E sub 6 leptoquarks and the solar neutrino problem

    NASA Technical Reports Server (NTRS)

    Roulet, Esteban

    1991-01-01

    The possibility that non-conventional neutrino oscillations take place in the superstring inspired E sub 6 models is considered. In this context, the influence of leptoquark mediated interactions of the neutrinos with nucleons in the resonant flavor conversion is discussed. It is shown that this effect can be significant for v sub e - v sub tau oscillations if these neutrinos have masses required in the ordinary Mikheyev-Smirnov-Wolfenstein (MSW) effect, and may lead to a solution of the solar neutrino problem even in the absence of vacuum mixings. On the other hand, this model cannot lead to a resonant behavior in the sun if the neutrinos are massless.

  20. Physics from solar neutrinos in dark matter direct detection experiments

    NASA Astrophysics Data System (ADS)

    Cerdeño, David G.; Fairbairn, Malcolm; Jubb, Thomas; Machado, Pedro A. N.; Vincent, Aaron C.; Bœhm, Céline

    2016-05-01

    The next generation of dark matter direct detection experiments will be sensitive to both coherent neutrino-nucleus and neutrino-electron scattering. This will enable them to explore aspects of solar physics, perform the lowest energy measurement of the weak angle sin2 θ W to date, and probe contributions from new theories with light mediators. In this article, we compute the projected nuclear and electron recoil rates expected in several dark matter direct detection experiments due to solar neutrinos, and use these estimates to quantify errors on future measurements of the neutrino fluxes, weak mixing angle and solar observables, as well as to constrain new physics in the neutrino sector. Our analysis shows that the combined rates of solar neutrino events in second generation experiments (SuperCDMS and LZ) can yield a measurement of the pp flux to 2.5% accuracy via electron recoil, and slightly improve the 8B flux determination. Assuming a low-mass argon phase, projected tonne-scale experiments like DARWIN can reduce the uncertainty on both the pp and boron-8 neutrino fluxes to below 1%. Finally, we use current results from LUX, SuperCDMS and CDMSlite to set bounds on new interactions between neutrinos and electrons or nuclei, and show that future direct detection experiments can be used to set complementary constraints on the parameter space associated with light mediators.

  1. Yet another possible explanation of the solar-neutrino puzzle

    SciTech Connect

    Kolb, E.W.; Turner, M.S.; Walker, T.P.

    1986-04-01

    Mikheyev and Smirnov have shown that the interactions of neutrinos with matter can result in the conversion of electron neutrinos produced in the center of the sun to muon neutrinos. Bethe has exploited this and has pointed out that the solar-neutrino puzzle can be resolved if the mass difference squared of the two neutrinos is m/sub 2//sup 2/ - m /sub 1//sup 2/ approx. = 6 x 10/sup -5/ eV/sup 2/, and the mixing angle satisfies sin theta/sub v/ > 0.0065. We discuss a qualitatively different solution to the solar-neutrino puzzle which requires 1.0 x 10/sup -8/ < (m/sub 2//sup 2/ - m/sub 1//sup 2/) (sin/sup 2/ 2theta/sub v//cos 2theta/sub v/) < 6.1 x 10/sup -8/ eV/sup 2/. Our solutions result in a much smaller flux of neutrinos from the p - p process than predicted by standard solar models, while Bethe's solution results in a flux of neutrinos from the p - process that is about the same as standard solar models.

  2. The Sudbury Neutrino Observatory: Observation of Flavor Change for Solar Neutrinos

    NASA Astrophysics Data System (ADS)

    McDonald, A. B.

    2016-03-01

    The Sudbury Neutrino Observatory (SNO) detector was developed by an international scientific collaboration (Canada, US, UK) to use 1000 tonnes of heavy water 2 km underground in ultra-clean conditions to observe flavor change for solar neutrinos from 8B decay in the sun. A clear observation of neutrino change was obtained by comparing two neutrino reactions on deuterium, one sensitive only to electron flavor neutrinos and one sensitive equally to all active neutrino types. The design and construction and the operation and data analysis for the three separate phases of the experiment will be described. The initial phase with pure heavy water provided conclusive evidence for flavor change and hence finite mass for neutrinos. Subsequent phases within added NaCl and with an array of neutron detectors provided improved accuracy for the measurements of oscillation parameters. The observed total flux of 8B solar electron neutrinos is in excellent agreement with and more accurate than solar models. Modification of the SNO detector to create SNO + and expansion of the laboratory to create a long-term international underground laboratory, SNOLAB, will be briefly described.

  3. Muon and Tau Neutrinos Spectra from Solar Flares

    NASA Astrophysics Data System (ADS)

    Fargion, Daniele; Moscato, Federica

    2003-12-01

    Most power-full solar flare as the ones occurred on 23th February 1956, September 29th 1989, 28th October and on 2nd-4th November 2003 are sources of cosmic rays, X, gamma and neutrino bursts. These flares took place both on front or in the edge and in the hidden solar disk. The 4th November event was the most powerful X event in the highest known rank category X28 just at horizons. The observed and estimated total flare energy (EFL ≃ 1031div 1033 erg) should be a source of a prompt secondary neutrino burst originated, by proton-proton-pion production on the sun itself; a more delayed and spread neutrino flux signal arise by the solar charged flare particles reaching the terrestrial atmosphere. These first earliest prompt solar neutrino burst might be observed, in a few neutrino clustered events, in present or future largest neutrino underground detectors as Super-Kamiokande one, in time correlation with the X-Radio flare. The onset in time correlation has great statistical significance. Our first estimate on the neutrino number events detection at the Super-Kamiokande II Laboratory for horizontal or hidden flare is found to be few events: NeV_bar{ν}_e≃ 0.63&etae ()/(35 MeV) ()/(1031 erg); and NeV_bar{ν}μ ≃ 3.58()/(200 MeV) ()/(1031erg) η,SUB>μ, where η≃ 1, Eνμ > 113 MeV. Our first estimates of neutrino signals in largest underground detectors hint for few events in correlation with X, gamma, radio onser. Our approximated spectra for muons and taus from these rare solar eruption are shown over the most common background. The muon and tau signature is very peculiar and characteristic over electron and anti-electron neutrino fluxes. The rise of muon neutrinos will be detectable above the minimal muon threshold Eν ≃ 113 MeV energy, or above the pion and Δ ° thresholds (Eν≃ 151 and 484 MeV). Any large neutrino flare event record might also verify the expected neutrino flavour mixing leading to a few as well as a comparable

  4. Resonant-Spin Flavour solutions to the Solar neutrino Problem

    NASA Astrophysics Data System (ADS)

    Miranda, O. G.

    2002-07-01

    Resonant spin-flavour solutions to the solar neutrino problem are introduced, in the framework of analytic solutions to the solar magneto-hydrodynamics equations. We study these solutions in a scheme with 3 effective parameters: the neutrino magnetic moment, the neutrino mass difference and mixing. We perform a fit of the solar neutrino data, including the recent SNO CC. We show how a rates-only analysis slightly flavours spin-flavour precession solutions over oscillations. In addition to the resonant solution, there is a new non-resonant solution in the dark-side. Both solutions lead to flat recoil energy spectra in excellent agreement with the latest SuperKamiokande data.

  5. Light sterile neutrinos, spin flavor precession, and the solar neutrino experiments

    NASA Astrophysics Data System (ADS)

    Das, C. R.; Pulido, João; Picariello, Marco

    2009-04-01

    We generalize to three active flavors a previous two-flavor model for the resonant spin flavor conversion of solar neutrinos to sterile ones, a mechanism which is added to the well-known large mixing angle (LMA) one. The transition magnetic moments from the muon and tau neutrinos to the sterile play the dominant role in fixing the amount of active flavor suppression. We also show, through numerical integration of the evolution equations, that the data from all solar neutrino experiments except Borexino exhibit a clear preference for a sizable magnetic field either in the convection zone or in the core and radiation zone. This is possibly related to the fact that the data from the first set are average ones taken during a period of mostly intense solar activity, whereas in contrast Borexino data were taken during a period of quiet Sun. We argue that the solar neutrino experiments are capable of tracing the possible modulation of the solar magnetic field. Those monitoring the high-energy neutrinos, namely, the B8 flux, appear to be sensitive to a field modulation either in the convection zone or in the core and radiation zone. Those monitoring the low-energy fluxes will be sensitive to the second type of solar field profiles only. In this way Borexino alone may play an essential role, since it examines both energy sectors, although experimental redundancy from other experiments will be most important.

  6. Solar neutrino measurements in Super-Kamiokande-IV

    NASA Astrophysics Data System (ADS)

    Abe, K.; Haga, Y.; Hayato, Y.; Ikeda, M.; Iyogi, K.; Kameda, J.; Kishimoto, Y.; Marti, Ll.; Miura, M.; Moriyama, S.; Nakahata, M.; Nakajima, T.; Nakayama, S.; Orii, A.; Sekiya, H.; Shiozawa, M.; Sonoda, Y.; Takeda, A.; Tanaka, H.; Takenaga, Y.; Tasaka, S.; Tomura, T.; Ueno, K.; Yokozawa, T.; Akutsu, R.; Irvine, T.; Kaji, H.; Kajita, T.; Kametani, I.; Kaneyuki, K.; Lee, K. P.; Nishimura, Y.; McLachlan, T.; Okumura, K.; Richard, E.; Labarga, L.; Fernandez, P.; Blaszczyk, F. d. M.; Gustafson, J.; Kachulis, C.; Kearns, E.; Raaf, J. L.; Stone, J. L.; Sulak, L. R.; Berkman, S.; Tobayama, S.; Goldhaber, M.; Bays, K.; Carminati, G.; Griskevich, N. J.; Kropp, W. R.; Mine, S.; Renshaw, A.; Smy, M. B.; Sobel, H. W.; Takhistov, V.; Weatherly, P.; Ganezer, K. S.; Hartfiel, B. L.; Hill, J.; Keig, W. E.; Hong, N.; Kim, J. Y.; Lim, I. T.; Park, R. G.; Akiri, T.; Albert, J. B.; Himmel, A.; Li, Z.; O'Sullivan, E.; Scholberg, K.; Walter, C. W.; Wongjirad, T.; Ishizuka, T.; Nakamura, T.; Jang, J. S.; Choi, K.; Learned, J. G.; Matsuno, S.; Smith, S. N.; Friend, M.; Hasegawa, T.; Ishida, T.; Ishii, T.; Kobayashi, T.; Nakadaira, T.; Nakamura, K.; Nishikawa, K.; Oyama, Y.; Sakashita, K.; Sekiguchi, T.; Tsukamoto, T.; Nakano, Y.; Suzuki, A. T.; Takeuchi, Y.; Yano, T.; Cao, S. V.; Hayashino, T.; Hiraki, T.; Hirota, S.; Huang, K.; Ieki, K.; Jiang, M.; Kikawa, T.; Minamino, A.; Murakami, A.; Nakaya, T.; Patel, N. D.; Suzuki, K.; Takahashi, S.; Wendell, R. A.; Fukuda, Y.; Itow, Y.; Mitsuka, G.; Muto, F.; Suzuki, T.; Mijakowski, P.; Frankiewicz, K.; Hignight, J.; Imber, J.; Jung, C. K.; Li, X.; Palomino, J. L.; Santucci, G.; Taylor, I.; Vilela, C.; Wilking, M. J.; Yanagisawa, C.; Fukuda, D.; Ishino, H.; Kayano, T.; Kibayashi, A.; Koshio, Y.; Mori, T.; Sakuda, M.; Takeuchi, J.; Yamaguchi, R.; Kuno, Y.; Tacik, R.; Kim, S. B.; Okazawa, H.; Choi, Y.; Ito, K.; Nishijima, K.; Koshiba, M.; Totsuka, Y.; Suda, Y.; Yokoyama, M.; Bronner, C.; Calland, R. G.; Hartz, M.; Martens, K.; Obayashi, Y.; Suzuki, Y.; Vagins, M. R.; Nantais, C. M.; Martin, J. F.; de Perio, P.; Tanaka, H. A.; Konaka, A.; Chen, S.; Sui, H.; Wan, L.; Yang, Z.; Zhang, H.; Zhang, Y.; Connolly, K.; Dziomba, M.; Wilkes, R. J.; Super-Kamiokande Collaboration

    2016-09-01

    Upgraded electronics, improved water system dynamics, better calibration and analysis techniques allowed Super-Kamiokande-IV to clearly observe very low-energy 8B solar neutrino interactions, with recoil electron kinetic energies as low as ˜3.5 MeV . Super-Kamiokande-IV data-taking began in September of 2008; this paper includes data until February 2014, a total livetime of 1664 days. The measured solar neutrino flux is (2.308 ±0.020 (stat)-0.040 +0.039(syst ))×1 06/(cm2 sec ) assuming no oscillations. The observed recoil electron energy spectrum is consistent with no distortions due to neutrino oscillations. An extended maximum likelihood fit to the amplitude of the expected solar zenith angle variation of the neutrino-electron elastic scattering rate in SK-IV results in a day/night asymmetry of (-3.6 ±1.6 (stat )±0.6 (syst ))% . The SK-IV solar neutrino data determine the solar mixing angle as sin2θ12=0.327-0.031+0.026 , all SK solar data (SK-I, SK-II, SK III and SK-IV) measures this angle to be sin2θ12=0.334-0.023+0.027 , the determined mass-squared splitting is Δ m212=4.8-0.8+1.5×10-5 eV2 .

  7. Evidence for electron neutrino flavor change through measurement of the (8)B solar neutrino flux at the Sudbury Neutrino Observatory

    NASA Astrophysics Data System (ADS)

    Neubauer, Mark Stephen

    2001-11-01

    The Sudbury Neutrino Observatory (SNO) is a water Cerenkov detector designed to study solar neutrinos. Using 1 kiloton of heavy water as the target and detection medium, SNO is able to separately determine the flux of electron neutrinos (νe) and the flux of all active neutrinos from the Sun by measuring the rate of charged current (CC) and neutral current (NC) interactions with deuterons. A comparison of these interaction rates allows for direct observation of solar neutrino oscillations. SNO can also search for oscillations by comparing the rate of CC and neutrino- electron elastic scattering (ES) events, since ES has both charged current and neutral current sensitivity. In this thesis, we present measurement of the 8B solar ν e flux of 1.78+0.13-0.14 (stat+syst) × 106cm-2s -1 (35% BP2000 SSM) through measurement of the CC rate over 169.3 days of livetime. We have also measured the 8B flux from the ES reaction to be 2.56+0.48-0.45 (stat+syst), consistent with measurements by previous water Cerenkov experiments. A flavor analysis comparing the CC measured flux with that determined through ES by SuperKamiokande yields a non- νe active neutrino flux from 8B of 3.62+1.06-1.08 × 106cm-2s-1 , providing evidence for νe --> ν μ,τ oscillations as a solution to the solar neutrino problem. This result excludes pure solar νe --> ν s oscillations at greater than the 99.7% C.I. The total active 8B neutrino flux has been measured to be 5.39+1.07-1.09 × 106cm-2s-1 , consistent with BP2000 SSM predictions. First analyses of the CC (NHit) spectrum and hep flux in SNO are presented. The CC spectrum is found to be a good fit to expectations from an undistorted 8B spectrum, and global best fit vacuum oscillation solutions are disfavored over the other solutions by the data. Through observations near the 8B endpoint with consideration of energy systematics, hep flux limits of 4.1 (90% C.I.) and 6.9 (99% C.I.) times SSM expectations are obtained. A statistical fit for the

  8. First indication of terrestrial matter effects on solar neutrino oscillation.

    PubMed

    Renshaw, A; Abe, K; Hayato, Y; Iyogi, K; Kameda, J; Kishimoto, Y; Miura, M; Moriyama, S; Nakahata, M; Nakano, Y; Nakayama, S; Sekiya, H; Shiozawa, M; Suzuki, Y; Takeda, A; Takenaga, Y; Tomura, T; Ueno, K; Yokozawa, T; Wendell, R A; Irvine, T; Kajita, T; Kaneyuki, K; Lee, K P; Nishimura, Y; Okumura, K; McLachlan, T; Labarga, L; Berkman, S; Tanaka, H A; Tobayama, S; Kearns, E; Raaf, J L; Stone, J L; Sulak, L R; Goldhabar, M; Bays, K; Carminati, G; Kropp, W R; Mine, S; Smy, M B; Sobel, H W; Ganezer, K S; Hill, J; Keig, W E; Hong, N; Kim, J Y; Lim, I T; Akiri, T; Himmel, A; Scholberg, K; Walter, C W; Wongjirad, T; Ishizuka, T; Tasaka, S; Jang, J S; Learned, J G; Matsuno, S; Smith, S N; Hasegawa, T; Ishida, T; Ishii, T; Kobayashi, T; Nakadaira, T; Nakamura, K; Oyama, Y; Sakashita, K; Sekiguchi, T; Tsukamoto, T; Suzuki, A T; Takeuchi, Y; Bronner, C; Hirota, S; Huang, K; Ieki, K; Ikeda, M; Kikawa, T; Minamino, A; Nakaya, T; Suzuki, K; Takahashi, S; Fukuda, Y; Choi, K; Itow, Y; Mitsuka, G; Mijakowski, P; Hignight, J; Imber, J; Jung, C K; Yanagisawa, C; Ishino, H; Kibayashi, A; Koshio, Y; Mori, T; Sakuda, M; Yano, T; Kuno, Y; Tacik, R; Kim, S B; Okazawa, H; Choi, Y; Nishijima, K; Koshiba, M; Totsuka, Y; Yokoyama, M; Martens, K; Marti, Ll; Vagins, M R; Martin, J F; de Perio, P; Konaka, A; Wilking, M J; Chen, S; Zhang, Y; Wilkes, R J

    2014-03-01

    We report an indication that the elastic scattering rate of solar B8 neutrinos with electrons in the Super-Kamiokande detector is larger when the neutrinos pass through Earth during nighttime. We determine the day-night asymmetry, defined as the difference of the average day rate and average night rate divided by the average of those two rates, to be [-3.2 ± 1.1(stat) ± 0.5(syst)]%, which deviates from zero by 2.7 σ. Since the elastic scattering process is mostly sensitive to electron-flavored solar neutrinos, a nonzero day-night asymmetry implies that the flavor oscillations of solar neutrinos are affected by the presence of matter within the neutrinos' flight path. Super-Kamiokande's day-night asymmetry is consistent with neutrino oscillations for 4 × 10(-5)  eV(2) ≤ Δm 2(21) ≤ 7 × 10(-5) eV(2) and large mixing values of θ12, at the 68% C.L. PMID:24655245

  9. Solar neutrinos and 1-3 leptonic mixing

    SciTech Connect

    Goswami, Srubabati; Smirnov, Alexei Yu.

    2005-09-01

    Effects of the 1-3 leptonic mixing on the solar neutrino observables are studied and the signatures of nonzero {theta}{sub 13} are identified. For this we have rederived the formula for 3{nu}-survival probability including all relevant corrections and constructed the isocontours of observables in the sin{sup 2}{theta}{sub 12}-sin{sup 2}{theta}{sub 13} plane. Analysis of the solar neutrino data gives sin{sup 2}{theta}{sub 13}=0.007{sub -0.007}{sup +0.080} (90% C.L.) for {delta}m{sup 2}=8x10{sup -5} eV{sup 2}. The combination of the ratio CC/NC at Sudbury Neutrino Observatory (SNO) and gallium production rate selects sin{sup 2}{theta}{sub 13}=0.017{+-}0.026 (1{sigma}). The global fit of all oscillation data leads to zero best value of sin{sup 2}{theta}{sub 13}. The sensitivity (1{sigma} error) of future solar neutrino studies to sin{sup 2}{theta}{sub 13} can be improved down to 0.01-0.02 by precise measurements of the pp-neutrino flux and the CC/NC ratio as well as spectrum distortion at high (E>4 MeV) energies. Combination of experimental results sensitive to the low and high energy parts of the solar neutrino spectrum resolves the degeneracy of angles {theta}{sub 13} and {theta}{sub 12}. Comparison of sin{sup 2}{theta}{sub 13} as well as sin{sup 2}{theta}{sub 12} measured in the solar neutrinos and in the reactor/accelerator experiments may reveal new effects which can not be seen otherwise.

  10. a Brief Critique of the Search for Neutrino Oscillations with “SINGLE MEASUREMENT” Solar Neutrino Experiments

    NASA Astrophysics Data System (ADS)

    Cline, David B.; Cheng, Mao-Tung

    We briefly review the recent results on solar neutrino observations pointing out the dependence on the model of the solar neutrino production. We show that current uncertainties make it rather unlikely that unambiguous proof of neutrino oscillations can be obtained from any current (single measurement) techniques. We then show the importance of carrying out solar neutrino experiments where two reactions are measured simultaneously (double experiments). As an example we apply this to the ICARUS liquid Argon detector being constructed for the Gran Sasso Laboratory.

  11. Charge exchange reactions and solar neutrino detection in 81Br

    NASA Astrophysics Data System (ADS)

    Liu, K. F.; Gabbard, F.

    1983-01-01

    The feasibility of 81Br as the detector of the solar neutrino flux hinges upon the knowledge of the Gamow-Teller matrix element from the ground state of 81Br to the 52- state at 0.457 MeV in 81Kr. The possibility of obtaining this matrix element is discussed in terms of the (p, n) and (3He, t) charge exchange reactions. NUCLEAR REACTIONS 81Br(p, n)81Kr and 81Br(3He, t)81Kr Gamow-Teller transitions; solar neutrino detection.

  12. First real-time detection of solar pp neutrinos by Borexino

    NASA Astrophysics Data System (ADS)

    Pallavicini, M.; Bellini, G.; Benziger, J.; Bick, D.; Bonfini, G.; Bravo, D.; Caccianiga, B.; 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.; Göger-Neff, M.; Goretti, A.; Gromov, M.; Hagner, C.; Hungerford, E.; Ianni, Al.; Ianni, An.; Kayser, M.; Kobychev, V.; Korablëv, 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.; Mosteiro, P.; Muratova, V.; Oberauer, L.; Obolensky, M.; Ortica, F.; Otis, K.; Papp, L.; Perasso, L.; Pocar, A.; Ranucci, G.; Razeto, A.; Re, A.; Romani, A.; Rossi, N.; Saldanha, R.; Salvo, C.; Schönert, S.; Simgen, H.; Skorokhvatov, M.; Smirnov, O.; Sotnikov, A.; Sukhotin, S.; Suvorov, Y.; Tartaglia, R.; Testera, G.; Vignaud, D.; Vogelaar, R. B.; von Feilitzsch, F.; Wang, H.; Winter, J.; Wojcik, M.; Wurm, M.; Zaimidoroga, O.; Zavatarelli, S.; Zuber, K.; Zuzel, G.

    2016-07-01

    Solar neutrinos have been pivotal to the discovery of neutrino flavour oscillations and are a unique tool to probe the reactions that keep the Sun shine. Although most of solar neutrino components have been directly measured, the neutrinos emitted by the keystone pp reaction, in which two protons fuse to make a deuteron, have so far eluded direct detection. The Borexino experiment, an ultra-pure liquid scintillator detector running at the Laboratori Nazionali del Gran Sasso in Italy, has now filled the gap, providing the first direct real time measurement of pp neutrinos and of the solar neutrino luminosity.

  13. Solar neutrinos and the influence of radiative opacities on solar models

    NASA Technical Reports Server (NTRS)

    Carson, T. R.; Ezer, D.; Stothers, R.

    1973-01-01

    Use of new radiative opacities based on the hot Thomas-Fermi model of the atom yields a predicted solar neutrino flux which is still considerably larger than the flux observed in Davis's Cl-37 experiment.

  14. Neutrino signals from electroweak bremsstrahlung in solar WIMP annihilation

    SciTech Connect

    Bell, Nicole F.; Brennan, Amelia J.; Jacques, Thomas D. E-mail: a.brennan@pgrad.unimelb.edu.au

    2012-10-01

    Bremsstrahlung of W and Z gauge bosons, or photons, can be an important dark matter annihilation channel. In many popular models in which the annihilation to a pair of light fermions is helicity suppressed, these bremsstrahlung processes can lift the suppression and thus become the dominant annihilation channels. The resulting dark matter annihilation products contain a large, energetic, neutrino component. We consider solar WIMP annihilation in the case where electroweak bremsstrahlung dominates, and calculate the resulting neutrino spectra. The flux consists of primary neutrinos produced in processes such as χχ→ν-bar νZ and χχ→ν-bar lW, and secondary neutrinos produced via the decays of gauge bosons and charged leptons. After dealing with the neutrino propagation and flavour evolution in the Sun, we consider the prospects for detection in neutrino experiments on Earth. We compare our signal with that for annihilation to W{sup +}W{sup −}, and show that, for a given annihilation rate, the bremsstrahlung annihilation channel produces a larger signal by a factor of a few.

  15. Nuclear processes and neutrino production in solar flares

    NASA Technical Reports Server (NTRS)

    Lingenfelter, R. E.; Ramaty, R.; Murphy, R. J.; Kozlovsky, S.

    1985-01-01

    The determination of flare neutrino flux is approached from the standpoint of recent observations and theoretical results on the nuclear processes in solar flares. Attention is given to the energy spectra and total numbers of accelerated particles in flares, as well as their resulting production of beta(+)-emitting radionuclei and pions; these should be the primary sources of neutrinos. The observed 0.511 MeV line flux for the June 21, 1980 flare is compared with the expected from the number and spectrum of accelerated particles.

  16. Can the measurement of the cross-section of proton-capture on beryllium-7 be improved?

    SciTech Connect

    Bowers, C.

    1993-01-01

    The solar neutrino ``problem`` arises from the discrepancy between the observations of solar neutrinos fluxes in experiments at Homestake and Kamiokande and the solar model predictions of those fluxes. Both experiments, which are sensitive mainly to high-energy neutrinos, observe fewer neutrinos than predicted by solar models. Most of the expected high-energy solar neutrinos come from the beta-decay of {sup 8}B, which is produced in the reaction {sup 7}Be(p,{gamma}){sup 8}B. A study of all of the measurements to date of the zero-energy S-factor for the reaction {sup 7}Be(p,{gamma}){sup 8}B concludes that S{sub 17}(0) = 0.0224 +{plus_minus} 0.0021 keV-barn. Although a 10% error in S{sub 17}(0) alone wig not solve the solar neutrino problem, it would still be useful to nail down all of the inputs of the solar models as well as possible. This serves to guard against the possibility that a conspiracy among the errors might be the source of the discrepancy and provides tighter constraints on the ``new physics`` interpretations of the experimentally measured solar neutrino spectrum. In this paper, we examine several ways of improving this measurement. None appear to offer a significant improvement over past experiments.

  17. Can the measurement of the cross-section of proton-capture on beryllium-7 be improved

    SciTech Connect

    Bowers, C.

    1993-01-01

    The solar neutrino problem'' arises from the discrepancy between the observations of solar neutrinos fluxes in experiments at Homestake and Kamiokande and the solar model predictions of those fluxes. Both experiments, which are sensitive mainly to high-energy neutrinos, observe fewer neutrinos than predicted by solar models. Most of the expected high-energy solar neutrinos come from the beta-decay of [sup 8]B, which is produced in the reaction [sup 7]Be(p,[gamma])[sup 8]B. A study of all of the measurements to date of the zero-energy S-factor for the reaction [sup 7]Be(p,[gamma])[sup 8]B concludes that S[sub 17](0) = 0.0224 +[plus minus] 0.0021 keV-barn. Although a 10% error in S[sub 17](0) alone wig not solve the solar neutrino problem, it would still be useful to nail down all of the inputs of the solar models as well as possible. This serves to guard against the possibility that a conspiracy among the errors might be the source of the discrepancy and provides tighter constraints on the new physics'' interpretations of the experimentally measured solar neutrino spectrum. In this paper, we examine several ways of improving this measurement. None appear to offer a significant improvement over past experiments.

  18. Contribution of gallium experiments to the understanding of solar physics and neutrino physics

    SciTech Connect

    Gavrin, V. N.

    2013-10-15

    The results of gallium measurements of solar neutrino and measurements with artificial sources of neutrinos are presented. Conclusions are drawn from these results, and the potential of the SAGE experiment for studying transitions of active neutrinos to sterile states for {Delta}m{sup 2} > 0.5 eV{sup 2} and a sensitivity of a few percent to the disappearance of electron neutrinos is examined.

  19. Stellar and primordial nucleosynthesis of 7Be: measurement of 3He(alpha,gamma)7Be.

    PubMed

    Di Leva, A; Gialanella, L; Kunz, R; Rogalla, D; Schürmann, D; Strieder, F; De Cesare, M; De Cesare, N; D'Onofrio, A; Fülöp, Z; Gyürky, G; Imbriani, G; Mangano, G; Ordine, A; Roca, V; Rolfs, C; Romano, M; Somorjai, E; Terrasi, F

    2009-06-12

    The 3He(alpha,gamma)7Be reaction presently represents the largest nuclear uncertainty in the predicted solar neutrino flux and has important implications on the big bang nucleosynthesis, i.e., the production of primordial 7Li. We present here the results of an experiment using the recoil separator ERNA (European Recoil separator for Nuclear Astrophysics) to detect directly the 7Be ejectiles. In addition, off-beam activation and coincidence gamma-ray measurements were performed at selected energies. At energies above 1 MeV a large discrepancy compared to previous results is observed both in the absolute value and in the energy dependence of the cross section. Based on the available data and models, a robust estimate of the cross section at the astrophysical relevant energies is proposed. PMID:19658929

  20. Stellar and primordial nucleosynthesis of 7Be: measurement of 3He(alpha,gamma)7Be.

    PubMed

    Di Leva, A; Gialanella, L; Kunz, R; Rogalla, D; Schürmann, D; Strieder, F; De Cesare, M; De Cesare, N; D'Onofrio, A; Fülöp, Z; Gyürky, G; Imbriani, G; Mangano, G; Ordine, A; Roca, V; Rolfs, C; Romano, M; Somorjai, E; Terrasi, F

    2009-06-12

    The 3He(alpha,gamma)7Be reaction presently represents the largest nuclear uncertainty in the predicted solar neutrino flux and has important implications on the big bang nucleosynthesis, i.e., the production of primordial 7Li. We present here the results of an experiment using the recoil separator ERNA (European Recoil separator for Nuclear Astrophysics) to detect directly the 7Be ejectiles. In addition, off-beam activation and coincidence gamma-ray measurements were performed at selected energies. At energies above 1 MeV a large discrepancy compared to previous results is observed both in the absolute value and in the energy dependence of the cross section. Based on the available data and models, a robust estimate of the cross section at the astrophysical relevant energies is proposed.

  1. A step toward CNO solar neutrino detection in liquid scintillators

    NASA Astrophysics Data System (ADS)

    Villante, F. L.; Ianni, A.; Lombardi, F.; Pagliaroli, G.; Vissani, F.

    2011-07-01

    The detection of CNO solar neutrinos in ultrapure liquid scintillator detectors is limited by the background produced by bismuth-210 nuclei that undergo β-decay to polonium-210 with a lifetime of ˜7 days. Polonium-210 nuclei are unstable and decay with a lifetime equal to ˜200 days emitting α particles that can be also detected. In this Letter, we show that the Bi-210 background can be determined by looking at the time evolution of α-decay rate of Po-210, provided that α particle detection efficiency is stable over the data acquisition period and external sources of Po-210 are negligible. A sufficient accuracy can be obtained in a relatively short time. As an example, if the initial Po-210 event rate is ˜2000 cpd/100 ton or lower, a Borexino-like detector could start discerning CNO neutrino signal from Bi-210 background in Δt˜1 yr.

  2. Solar neutrino interactions with liquid scintillators used for double beta-decay experiments

    NASA Astrophysics Data System (ADS)

    Ejiri, Hiroyasu; Zuber, Kai

    2016-08-01

    Solar neutrinos interact within double-beta-decay (DBD) detectors and hence will contribute to backgrounds (BGs) for DBD experiments. Background contributions due to solar neutrinos are evaluated for their interactions with atomic electrons and nuclei in liquid scintillation detectors used for DBD experiments. They are shown to be serious BGs for high-sensitivity DBD experiments to search for the Majorana neutrino masses in the inverted and normal hierarchy regions.

  3. Magnetic neutrino resonant spin-flavor precession, 2. Helio-latitudinal asymmetry of solar neutrino fluxes and correlation coefficients.

    NASA Astrophysics Data System (ADS)

    Dorman, L. I.

    2001-08-01

    On the bases of available Homestake experimental data (Cleveland et al., 1998) for more than two solar cycles (1970-1994) we determine for each solar neutrino run "n" effective helio-latitude Lef(n). Then we separate all Homestake runs on three equal helio -latitudinal zones: SOUTHERLY, EQUATORIAL, and NORTHERLY with average helio-latitudes -5.3, -0.3 and +5.3 degrees, correspondingly. For each zone and each run we found effective Zurich sunspot number Zef(n), total effective surface of sunspots STef(n), as well as effective surfaces of sunspots in different non-symmetrical helio-latitudinal belts. We separated also all runs on 3 equal groups of LOW, MEDIUM and HIGH solar activity with average sunspot numbers 25.0, 80.1 and 149.9. We found that the biggest decrease of solar neutrino flux with increasing of solar activity was observed in EQUATORIAL zone: from 3.6 SNU at LOW solar activity to 2.1 SNU at HIGH solar activity. The biggest SOUTH -NORTH asymmetry in solar neutrino fluxes was observed in group of runs at LOW solar activity: 2.9 SNU in SOUTHERLY zone and 2.1 SNU in NORTHERLY zone. The SOUTHNORTH asymmetry is found also in correlation coefficients between solar neutrino fluxes in the helio-latitudinal zones SOUTHERLY, EQUATORIAL, and NORTHERLY with solar activity in different non-symmetrical helio-latitudinal belts. Obtained results support the model of magnetic neutrino resonant spin-flavor precession.

  4. Determination of the 3He+α→7Be asymptotic normalization coefficients, the nuclear vertex constants, and their application for the extrapolation of the 3He(α,γ)7Be astrophysical S factors to the solar energy region

    NASA Astrophysics Data System (ADS)

    Tursunmahatov, Q. I.; Yarmukhamedov, R.

    2012-04-01

    A new analysis of the modern astrophysical S factors for the direct-capture 3He(α,γ)7Be reaction, precisely measured in recent works [B.S. Nara Singh , Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.93.262503 93, 262503 (2004); D. Bemmerer , Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.97.122502 97, 122502 (2006);F. Confortola , Phys. Rev. CPRVCAN0556-281310.1103/PhysRevC.75.065803 75, 065803 (2007), Gy. Gyürky , Phys. Rev. CPRVCAN0556-281310.1103/PhysRevC.75.035805 75, 035805 (2007), T. A. D. Brown , Phys. Rev. CPRVCAN0556-281310.1103/PhysRevC.76.055801 76, 055801 (2007), and A. Di Leva, , Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.102.232502 102, 232502 (2009)], has been carried out within the modified two-body potential approach. New estimates are obtained for the “indirectly determined” values of the asymptotic normalization constants and the respective nuclear vertex constants for 3He+α→7Be(g.s.) and 3He+α→7Be(0.429 MeV) as well as the astrophysical S factors S34(E) at E≤90 keV, including E=0. The values of asymptotic normalization constants have been used to obtain the values of the ratio of the α-particle spectroscopic factors for the mirror (7Li7Be) pair.

  5. Quasi-biennial modulation of solar neutrino flux: connections with solar activity

    NASA Astrophysics Data System (ADS)

    Vecchio, A.; Laurenza, M.; D'alessi, L.; Carbone, V.; Storini, M.

    2011-12-01

    A quasi-biennial periodicity has been recently found (Vecchio et al., 2010) in the solar neutrino flux, as detected at the Homestake experiment, as well as in the flux of solar energetic protons, by means of the Empirical Modes Decomposition technique. Moreover, both fluxes have been found to be significantly correlated at the quasi-biennial timescale, thus supporting the hypothesis of a connection between solar neutrinos and solar activity. The origin of this connection is investigated, by modeling how the standard Mikheyev-Smirnov-Wolfenstein (MSW) effect (the process for which the well-known neutrino flavor oscillations are modified in passing through the material) could be influenced by matter fluctuations. As proposed by Burgess et al., 2004, by introducing a background magnetic field in the helioseismic model, density fluctuations can be excited in the radiative zone by the resonance between helioseismic g-modes and Alfvén waves. In particular, with reasonable values of the background magnetic field (10-100 kG), the distance between resonant layers could be of the same order of neutrino oscillation length. We study the effect over this distance of a background magnetic field which is variable with a ~2 yr period, in agreement with typical variations of solar activity. Our findings suggest that the quasi-biennial modulation of the neutrino flux is theoretically possible as a consequence of the magnetic field variations in the solar interior. A. Vecchio, M. Laurenza, V. Carbone, M. Storini, The Astrophysical Journal Letters, 709, L1-L5 (2010). C. Burgess, N. S. Dzhalilov, T. I. Rashba, V., B.Semikoz, J. W. F. Valle, Mon. Not. R. Astron. Soc., 348, 609-624 (2004).

  6. The status of the solar neutrino problem and the Russian-American gallium experiment (SAGE)

    SciTech Connect

    Bowles, T.J.

    1994-04-01

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

  7. The solar neutrino puzzle and the vL --> vR conversion hypothesis

    NASA Astrophysics Data System (ADS)

    Barbieri, R.; Fiorentini, G.

    As a possible explanation of the solar neutrino puzzle, several authors have invoked a neutrino helicity rotation (vL --> vR) in the solar magnetic field, coupled to a neutrino magnetic moment. We discuss: (i) the effect on the vL --> vR conversion probability of the different coherent interaction with matter of the two neutrino helicity states; (ii) the azimuthal asymmetry in the elastic v-e scattering of solar neutrinos, due to the interference between the weak and the electromagnetic amplitude. We also briefly comment on the theoretical problem posed by a neutrino magnetic moment as large as 10-10μB. Dipartimento di Fisica, Università di Cagliari, Italy.

  8. Measurement of the total active 8B solar neutrino flux at the Sudbury Neutrino Observatory with enhanced neutral current sensitivity.

    PubMed

    Ahmed, S N; Anthony, A E; Beier, E W; Bellerive, A; Biller, S D; Boger, J; Boulay, M G; Bowler, M G; Bowles, T J; Brice, S J; Bullard, T V; Chan, Y D; Chen, M; Chen, X; Cleveland, B T; Cox, G A; Dai, X; Dalnoki-Veress, F; Doe, P J; Dosanjh, R S; Doucas, G; Dragowsky, M R; Duba, C A; Duncan, F A; Dunford, M; Dunmore, J A; Earle, E D; Elliott, S R; Evans, H C; Ewan, G T; Farine, J; Fergani, H; Fleurot, F; Formaggio, J A; Fowler, M M; Frame, K; Fulsom, B G; Gagnon, N; Graham, K; Grant, D R; Hahn, R L; Hall, J C; Hallin, A L; Hallman, E D; Hamer, A S; Handler, W B; Hargrove, C K; Harvey, P J; Hazama, R; Heeger, K M; Heintzelman, W J; Heise, J; Helmer, R L; Hemingway, R J; Hime, A; Howe, M A; Jagam, P; Jelley, N A; Klein, J R; Kos, M S; Krumins, A V; Kutter, T; Kyba, C C M; Labranche, H; Lange, R; Law, J; Lawson, I T; Lesko, K T; Leslie, J R; Levine, I; Luoma, S; MacLellan, R; Majerus, S; Mak, H B; Maneira, J; Marino, A D; McCauley, N; McDonald, A B; McGee, S; McGregor, G; Mifflin, C; Miknaitis, K K S; Miller, G G; Moffat, B A; Nally, C W; Nickel, B G; Noble, A J; Norman, E B; Oblath, N S; Okada, C E; Ollerhead, R W; Orrell, J L; Oser, S M; Ouellet, C; Peeters, S J M; Poon, A W P; Robertson, B C; Robertson, R G H; Rollin, E; Rosendahl, S S E; Rusu, V L; Schwendener, M H; Simard, O; Simpson, J J; Sims, C J; Sinclair, D; Skensved, P; Smith, M W E; Starinsky, N; Stokstad, R G; Stonehill, L C; Tafirout, R; Takeuchi, Y; Tesić, G; Thomson, M; Thorman, M; Van Berg, R; Van de Water, R G; Virtue, C J; Wall, B L; Waller, D; Waltham, C E; Tseung, H Wan Chan; Wark, D L; West, N; Wilhelmy, J B; Wilkerson, J F; Wilson, J R; Wouters, J M; Yeh, M; Zuber, K

    2004-05-01

    The Sudbury Neutrino Observatory has precisely determined the total active (nu(x)) 8B solar neutrino flux without assumptions about the energy dependence of the nu(e) survival probability. The measurements were made with dissolved NaCl in heavy water to enhance the sensitivity and signature for neutral-current interactions. The flux is found to be 5.21 +/- 0.27(stat)+/-0.38(syst) x 10(6) cm(-2) s(-1), in agreement with previous measurements and standard solar models. A global analysis of these and other solar and reactor neutrino results yields Deltam(2)=7.1(+1.2)(-0.6) x 10(-5) eV(2) and theta=32.5(+2.4)(-2.3) degrees. Maximal mixing is rejected at the equivalent of 5.4 standard deviations.

  9. ecCNO solar neutrinos: A challenge for gigantic ultra-pure liquid scintillator detectors

    NASA Astrophysics Data System (ADS)

    Villante, F. L.

    2015-03-01

    Neutrinos produced in the Sun by electron capture reactions on 13N, 15O and 17F, to which we refer as ecCNO neutrinos, are not usually considered in solar neutrino analysis since the expected fluxes are extremely low. The experimental determination of this sub-dominant component of the solar neutrino flux is very difficult but could be rewarding since it provides a determination of the metallic content of the solar core and, moreover, probes the solar neutrino survival probability in the transition region at Eν ∼ 2.5 MeV. In this Letter, we suggest that this difficult measure could be at reach for future gigantic ultra-pure liquid scintillator detectors, such as LENA.

  10. Search for Environmental Influences on the ^7Be Decay Rate*

    NASA Astrophysics Data System (ADS)

    Norman, E. B.; Rech, G. A.; Dragowsky, M. R.; Chan, Y. D.; Perillo Isaac, M. C.; Larimer, R.-M.

    1998-10-01

    ^7Be plays an important role in the generation of solar neutrinos. Because ^7Be decays via electron capture, its half life depends on the electron density at the nucleus. Two groups have recently reported observations of variations on the order of 1 percent in the decay rate of ^7Be as a function of the physical environment in which the ^7Be is located.^1,2 In order to test this idea, we measured the half life of ^7Be in four different materials. Samples of ^7Be in graphite, boron nitride, tantalum, and gold were produced at LBNL's 88" Cyclotron. Each ^7Be sample was packaged together with a ^133Ba reference source and then counted in 1-day time bins periodically over a 4-month period using a germanium detector. In order to reduce systematic effects from variations in detector or electronics performance, the ^7Be half life was determined by comparing the numbers of 478-keV ^7Be and 356-keV ^133Ba gamma rays from each sample. Results from analysis of this data will be presented. *Work supported by the U.S. Dept. of Energy under contract Nos. DE-AC03-76SF00098 and DE-FG03-98ER41060. 1. D. Souza et al., Bull. Am. Phys. Soc. 42, 1679 (1997). 2. A. Ray et al., submitted to Phys. Rev. Lett. (1998).

  11. Neutrino Experiments

    SciTech Connect

    McKeown, R. D.

    2010-08-04

    Recent studies of neutrino oscillations have established the existence of finite neutrino masses and mixing between generations of neutrinos. The combined results from studies of atmospheric neutrinos, solar neutrinos, reactor antineutrinos and neutrinos produced at accelerators paint an intriguing picture that clearly requires modification of the standard model of particle physics. These results also provide clear motivation for future neutrino oscillation experiments as well as searches for direct neutrino mass and nuclear double-beta decay. I will discuss the program of new neutrino oscillation experiments aimed at completing our knowledge of the neutrino mixing matrix.

  12. Measurement of the νe and total 8B solar neutrino fluxes with the Sudbury Neutrino Observatory phase-III data set

    NASA Astrophysics Data System (ADS)

    Aharmim, B.; Ahmed, S. N.; Amsbaugh, J. F.; Anaya, J. M.; Anthony, A. E.; Banar, J.; Barros, N.; Beier, E. W.; Bellerive, A.; Beltran, B.; Bergevin, M.; Biller, S. D.; Boudjemline, K.; Boulay, M. G.; Bowles, T. J.; Browne, M. C.; Bullard, T. V.; Burritt, T. H.; Cai, B.; Chan, Y. D.; Chauhan, D.; Chen, M.; Cleveland, B. T.; Cox, G. A.; Currat, C. A.; Dai, X.; Deng, H.; Detwiler, J. A.; DiMarco, M.; Doe, P. J.; Doucas, G.; Dragowsky, M. R.; Drouin, P.-L.; Duba, C. A.; Duncan, F. A.; Dunford, M.; Earle, E. D.; Elliott, S. R.; Evans, H. C.; Ewan, G. T.; Farine, J.; Fergani, H.; Fleurot, F.; Ford, R. J.; Formaggio, J. A.; Fowler, M. M.; Gagnon, N.; Germani, J. V.; Goldschmidt, A.; Goon, J. TM.; Graham, K.; Guillian, E.; Habib, S.; Hahn, R. L.; Hallin, A. L.; Hallman, E. D.; Hamian, A. A.; Harper, G. C.; Harvey, P. J.; Hazama, R.; Heeger, K. M.; Heintzelman, W. J.; Heise, J.; Helmer, R. L.; Henning, R.; Hime, A.; Howard, C.; Howe, M. A.; Huang, M.; Jagam, P.; Jamieson, B.; Jelley, N. A.; Keeter, K. J.; Klein, J. R.; Kormos, L. L.; Kos, M.; Krüger, A.; Kraus, C.; Krauss, C. B.; Kutter, T.; Kyba, C. C. M.; Lange, R.; Law, J.; Lawson, I. T.; Lesko, K. T.; Leslie, J. R.; Loach, J. C.; MacLellan, R.; Majerus, S.; Mak, H. B.; Maneira, J.; Martin, R.; McCauley, N.; McDonald, A. B.; McGee, S. R.; Mifflin, C.; Miller, G. G.; Miller, M. L.; Monreal, B.; Monroe, J.; Morissette, B.; Myers, A. W.; Nickel, B. G.; Noble, A. J.; O'Keeffe, H. M.; Oblath, N. S.; Ollerhead, R. W.; Orebi Gann, G. D.; Oser, S. M.; Ott, R. A.; Peeters, S. J. M.; Poon, A. W. P.; Prior, G.; Reitzner, S. D.; Rielage, K.; Robertson, B. C.; Robertson, R. G. H.; Rollin, E.; Schwendener, M. H.; Secrest, J. A.; Seibert, S. R.; Simard, O.; Simpson, J. J.; Skensved, P.; Smith, M. W. E.; Sonley, T. J.; Steiger, T. D.; Stonehill, L. C.; Tešić, G.; Thornewell, P. M.; Tolich, N.; Tsui, T.; Tunnell, C. D.; Van Wechel, T.; Van Berg, R.; VanDevender, B. A.; Virtue, C. J.; Wall, B. L.; Waller, D.; Wan Chan Tseung, H.; Wendland, J.; West, N.; Wilhelmy, J. B.; Wilkerson, J. F.; Wilson, J. R.; Wouters, J. M.; Wright, A.; Yeh, M.; Zhang, F.; Zuber, K.

    2013-01-01

    This paper details the solar neutrino analysis of the 385.17-day phase-III data set acquired by the Sudbury Neutrino Observatory (SNO). An array of 3He proportional counters was installed in the heavy-water target to measure precisely the rate of neutrino-deuteron neutral-current interactions. This technique to determine the total active 8B solar neutrino flux was largely independent of the methods employed in previous phases. The total flux of active neutrinos was measured to be 5.54-0.31+0.33(stat.)-0.34+0.36(syst.)×106 cm-2 s-1, consistent with previous measurements and standard solar models. A global analysis of solar and reactor neutrino mixing parameters yielded the best-fit values of Δm2=7.59-0.21+0.19×10-5eV2 and θ=34.4-1.2+1.3degrees.

  13. Solar neutrinos as background in dark matter searches involving electron detection

    NASA Astrophysics Data System (ADS)

    Thomas, A. W.; Vergados, J. D.

    2016-07-01

    In the present work we estimate the potential background of solar neutrinos on electron detectors. These detectors are considered relevant for detecting light dark matter particles in the MeV region, currently sought by experiments. We find that the copious low energy pp neutrinos are a dangerous background at the energies involved in these experiments, in fact close to the anticipated event rate, while the more energetic Boron neutrinos are harmless.

  14. Measurement of the reaction ^7Be(p,γ)^8B with a solid radioactive target

    NASA Astrophysics Data System (ADS)

    Greife, Uwe

    2000-04-01

    The reaction ^7Be(p,γ)^8B is regarded as a key to the understanding of the solar neutrino spectrum and thus most probably to the understanding of new neutrino properties. This contribution describes an experiment measuring the absolute cross section of ^7Be(p,γ)^8B with a solid radioactive target in the energy range between 350 keV and 2.6 MeV. The experiment was performed at the Dynamitron Tandem Laboratory of the Ruhr-Universitaet Bochum, Germany.

  15. The status of the study of solar CNO neutrinos in the Borexino experiment

    SciTech Connect

    Lukyanchenko, G. A.; Collaboration: Borexino Collaboration

    2015-12-15

    Although less than 1% of solar energy is generated in the CNO cycle, it plays a critical role in astrophysics, since this cycle is the primary source of energy in certain more massive stars and at later stages of evolution of solar-type stars. Electron neutrinos are produced in the CNO cycle reactions. These neutrinos may be detected by terrestrial neutrino detectors. Various solar models with different abundances of elements heavier than helium predict different CNO neutrino fluxes. A direct measurement of the CNO neutrino flux could help distinguish between these models and solve several other astrophysical problems. No CNO neutrinos have been detected directly thus far, and the best upper limit on their flux was set in the Borexino experiment. The work on reducing the background in the region of energies of CNO neutrinos (up to 1.74 MeV) and developing novel data analysis methods is presently under way. These efforts may help detect the CNO neutrino flux in the Borexino experiment at the level predicted by solar models.

  16. Experimental status of 7Be production and destruction at astrophysical relevant energies

    NASA Astrophysics Data System (ADS)

    Di Leva, A.; Gialanella, L.; Strieder, F.

    2016-01-01

    The production and destruction of 7Be plays a significant role in the Big Bang Nucleosynthesis as well as in the framework of the solar neutrino. The 3He(α, γ)7Be reaction cross sections has been measured several times in the last decades, but the precision achieved on reaction rate determinations at the relevant astrophysical energies is not yet satisfactory. The experimental status of this reaction will be critically reviewed, and the theoretical descriptions available will be discussed.

  17. Neutrinos

    PubMed Central

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

    1999-01-01

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

  18. The SNO+ Scintillator Purification Plant and Projected Sensitivity to Solar Neutrinos in the Pure Scintillator Phase

    NASA Astrophysics Data System (ADS)

    Pershing, Teal; SNO+ Collaboration

    2016-03-01

    The SNO+ detector is a neutrino and neutrinoless double-beta decay experiment utilizing the renovated SNO detector. In the second phase of operation, the SNO+ detector will contain 780 tons of organic liquid scintillator composed of 2 g/L 2,5-diphenyloxazole (PPO) in linear alkylbenzene (LAB). In this phase, SNO+ will strive to detect solar neutrinos in the sub-MeV range, including CNO production neutrinos and pp production neutrinos. To achieve the necessary detector sensitivity, a four-part scintillator purification plant has been constructed in SNOLAB for the removal of ionic and radioactive impurities. We present an overview of the SNO+ scintillator purification plant stages, including distillation, water extraction, gas stripping, and metal scavenger columns. We also give the projected SNO+ sensitivities to various solar-produced neutrinos based on the scintillator plant's projected purification efficiency.

  19. Neutrino Physics

    NASA Astrophysics Data System (ADS)

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

    2006-03-01

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

  20. Solar neutrinos: Near-far asymmetry and just-so oscillations

    SciTech Connect

    Faied, B.; Fogli, G.L.; Montanino, D.

    1997-02-01

    We propose to study possible signals of just-so oscillations in new-generation solar neutrino experiments by separating the events detected when the Earth is nearest to the Sun (perihelion {plus_minus} 3 months) from those detected when the Earth is farthest from the Sun (aphelion {plus_minus} 3 months). We introduce a solar-model-independent near-far asymmetry, which is nonzero if just-so oscillations occur. We apply our calculations to the kinetic energy spectra of electrons induced by {sup 8}B solar neutrino interactions in the SuperKamiokande and Sudbury Neutrino Observatory experiments. We show that the sensitivity to the neutrino oscillation parameters can be increased by probing the near-far asymmetry in selected parts of the electron energy spectra. {copyright} {ital 1997} {ital The American Physical Society}

  1. Neutrino physics with JUNO

    NASA Astrophysics Data System (ADS)

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

    2016-03-01

    . Detection of neutrinos from all past core-collapse supernova explosions in the visible universe with JUNO would further provide valuable information on the cosmic star-formation rate and the average core-collapse neutrino energy spectrum. Antineutrinos originating from the radioactive decay of uranium and thorium in the Earth can be detected in JUNO with a rate of ˜400 events per year, significantly improving the statistics of existing geoneutrino event samples. Atmospheric neutrino events collected in JUNO can provide independent inputs for determining the MH and the octant of the {θ }23 mixing angle. Detection of the 7Be and 8B solar neutrino events at JUNO would shed new light on the solar metallicity problem and examine the transition region between the vacuum and matter dominated neutrino oscillations. Regarding light sterile neutrino topics, sterile neutrinos with {10}-5 {{{eV}}}2\\lt {{Δ }}{m}412\\lt {10}-2 {{{eV}}}2 and a sufficiently large mixing angle {θ }14 could be identified through a precise measurement of the reactor antineutrino energy spectrum. Meanwhile, JUNO can also provide us excellent opportunities to test the eV-scale sterile neutrino hypothesis, using either the radioactive neutrino sources or a cyclotron-produced neutrino beam. The JUNO detector is also sensitive to several other beyondthe-standard-model physics. Examples include the search for proton decay via the p\\to {K}++\\bar{ν } decay channel, search for neutrinos resulting from dark-matter annihilation in the Sun, search for violation of Lorentz invariance via the sidereal modulation of the reactor neutrino event rate, and search for the effects of non-standard interactions. The proposed construction of the JUNO detector will provide a unique facility to address many outstanding crucial questions in particle and astrophysics in a timely and cost-effective fashion. It holds the great potential for further advancing our quest to understanding the fundamental properties of neutrinos, one

  2. Measurement of the 8B Solar Neutrino Flux with KamLAND

    SciTech Connect

    Abe, S.; Furuno, K.; Gando, A.; Gando, Y.; Ichimura, K.; Ikeda, H.; Inoue, K.; Kibe, Y.; Kimura, W.; Kishimoto, Y.; Koga, M.; Minekawa, Y.; Mitsui, T.; Morikawa, T.; Nagai, N.; Nakajima, K.; Nakamura, K.; Nakamura, M.; Narita, K.; Shimizu, I.; Shimizu, Y.; Shirai, J.; Suekane, F.; Suzuki, A.; Takahashi, H.; Takahashi, N.; Takemoto, Y.; Tamae, K.; Watanabe, H.; Xu, B.D.; Yabumoto, H.; Yonezawa, E.; Yoshida, H.; Yoshida, S.; Enomoto, S.; Kozlov, A.; Murayama, H.; Grant, C.; Keefer, G.; McKee, D.; Piepke, A.; Banks, T.I.; Bloxham, T.; Detwiler, J.A.; Freedman, S.J.; Fujikawa, B.K.; Han, K.; Kadel, R.; O'Donnell, T.; Steiner, H.M.; Winslow, L.A.; Dwyer, D.A.; Mauger, C.; McKeown, R.D.; Zhang, C.; Berger, B.E.; Lane, C.E.; Maricic, J.; Miletic, T.; Batygov, M.; Learned, J.G.; Matsuno, S.; Pakvasa, S.; Sakai, M.; Horton-Smith, G.A.; Tang, A.; Downum, K.E.; Gratta, G.; Tolich, K.; Efremenko, Y.; Kamyshkov, Y.; Perevozchikov, O.; Karwowski, H.J.; Markoff, D.M.; Tornow, W.; Heeger, K.M.; Piquemal, F.; Ricol, J.-S.; Decowski, M.P.

    2011-06-04

    We report a measurement of the neutrino-electron elastic scattering rate from {sup 8}B solar neutrinos based on a 123 kton-day exposure of KamLAND. The background-subtracted electron recoil rate, above a 5.5-MeV analysis threshold is 1.49 {+-} 0.14(stat) {+-} 0.17(syst) events per kton-day. Interpreted as due to a pure electron flavor flux with a {sup 8}B neutrino spectrum, this corresponds to a spectrum integrated flux of 2.77 {+-} 0.26(stat) {+-} 0.32(syst) x 10{sup 6} cm{sup -2}s{sup -1}. The analysis threshold is driven by {sup 208}Tl present in the liquid scintillator, and the main source of systematic uncertainty is due to background from cosmogenic {sup 11}Be. The measured rate is consistent with existing measurements and with standard solar model predictions which include matter-enhanced neutrino oscillation.

  3. On the question of the magnitude of day-night asymmetry for solar neutrinos

    SciTech Connect

    Aleshin, S. S. Lobanov, A. E. Kharlanov, O. G.

    2013-09-15

    The effect of flavor day-night asymmetry is considered for solar neutrinos of energy about 1 MeV under the assumption that the electron-density distribution within the Earth is approximately piecewise continuous on the scale of the neutrino-oscillation length. In this approximation, the resulting asymmetry factor for beryllium neutrinos does not depend on the structure of the inner Earth's layers or on the properties of the detector used. Its numerical estimate is on the order of -4 Multiplication-Sign 10{sup -4}, which is far beyond the reach of present-day experiments.

  4. DETECTING GRAVITY MODES IN THE SOLAR {sup 8} B NEUTRINO FLUX

    SciTech Connect

    Lopes, Ilídio; Turck-Chièze, Sylvaine E-mail: ilopes@uevora.pt

    2014-09-10

    The detection of gravity modes produced in the solar radiative zone has been a challenge in modern astrophysics for more than 30 yr and their amplitude in the core is not yet determined. In this Letter, we develop a new strategy to look for standing gravity modes through solar neutrino fluxes. We note that due to a resonance effect, the gravity modes of low degree and low order have the largest impact on the {sup 8} B neutrino flux. The strongest effect is expected to occur for the dipole mode with radial order 2, corresponding to periods of about 1.5 hr. These standing gravity waves produce temperature fluctuations that are amplified by a factor of 170 in the boron neutrino flux for the corresponding period, in consonance with the gravity modes. From current neutrino observations, we determine that the maximum temperature variation due to the gravity modes in the Sun's core is smaller than 5.8 × 10{sup –4}. This study clearly shows that due to their high sensitivity to the temperature, the {sup 8} B neutrino flux time series is an excellent tool to determine the properties of gravity modes in the solar core. Moreover, if gravity mode footprints are discovered in the {sup 8} B neutrino flux, this opens a new line of research to probe the physics of the solar core as non-standing gravity waves of higher periods cannot be directly detected by helioseismology but could leave their signature on boron neutrino or on other neutrino fluxes.

  5. Solar neutrinos and the MSW effect for three-neutrino mixing

    NASA Technical Reports Server (NTRS)

    Shi, X.; Schramm, David N.

    1991-01-01

    Researchers considered three-neutrino Mikheyev-Smirnov-Wolfenstein (MSW) mixing, assuming m sub 3 is much greater than m sub 2 is greater than m sub 1 as expected from theoretical consideration if neutrinos have mass. They calculated the corresponding mixing parameter space allowed by the Cl-37 and Kamiokande 2 experiments. They also calculated the expected depletion for the Ga-71 experiment. They explored a range of theoretical uncertainty due to possible astrophysical effects by varying the B-8 neutrino flux and redoing the MSW mixing calculation.

  6. Electron events from the scattering with solar neutrinos in the search of keV scale sterile neutrino dark matter

    NASA Astrophysics Data System (ADS)

    Liao, Wei; Wu, Xiao-Hong; Zhou, Hang

    2014-05-01

    In a previous work, we showed that it is possible to detect keV scale sterile neutrino dark matter νs in a β decay experiment using radioactive sources such as T3 or Ru106. The signals of this dark matter candidate are monoenergetic electrons produced in the neutrino capture process νs+ N'→N+e-. These electrons have energy greater than the maximum energy of the electrons produced in the associated decay process N'→N+e-+ν ¯e. Hence, signal electron events are well beyond the end point of the β decay spectrum and are not polluted by the β decay process. Another possible background, which is a potential threat to the detection of νs dark matter, is the electron event produced by the scattering of solar neutrinos with electrons in target matter. In this article, we study in detail this possible background and discuss its implications for the detection of keV scale sterile neutrino dark matter. In particular, bound state features of electrons in Ru atoms are considered with care in the scattering process when the kinetic energy of the final electron is the same order of magnitude of the binding energy.

  7. The fluxes of CN neutrinos from the Sun in case of mixing in a spherical layer in the solar core

    SciTech Connect

    Kopylov, Anatoly; Petukhov, Valery E-mail: beril@inr.ru

    2012-03-01

    The results of the calculation are presented for the fluxes of CN neutrinos from the Sun in case of mixing in a spherical layer in the solar core, consistent with the seismic data and with the measured solar neutrino fluxes. It is shown that a substantial increase of the flux of {sup 13}N neutrinos can be gained in this case. The possible implications for experiment are discussed.

  8. First observation of beryllium-7 solar neutrinos with KamLAND

    NASA Astrophysics Data System (ADS)

    Keefer, Gregory J.

    2009-09-01

    The international KamLAND collaboration operates a 1 kton liquid scintillation detector in the Kamioka mine in Gifu, Japan. KamLAND's main scientific results are the precision measurement of the solar Dm 2 12 = 7.58[Special characters omitted.] (stat) [Special characters omitted.] (syst) and tan 2 [straight theta] 12 = 0.56[Special characters omitted.] (stat) [Special characters omitted.] (syst) utilizing reactor n e and first evidence for the observation of geologically produced anti-neutrinos. In an effort to extend KamLAND's scientific reach, extensive research has been performed on preparing a spectroscopic measurement of 7 Be solar n e s. This work provides the first inclusive analysis of KamLAND's backgrounds below 1 MeV. 85 Kr and 210 Pb, dissolved in KamLAND liquid scintillator, were found to be the dominant source of low energy backgrounds. The concentration of these ultra-trace contaminants were determined to be 10 -20 g/g. This is more than 6 orders of magnitude lower than commercially available ultra-pure liquids. To attain a signal-to-background ratio suitable for the detection of 7 Be solar n e s, the concentration of these contaminants had to be reduced by 5 orders of magnitude. A comprehensive study of 210 Pb removal was undertaken over the course of this thesis. This work further covers techniques for the removal of 220 Rn, 222 Rn and their daughter nuclei from liquid scintillator at concentrations of 10^-18 g/g. Purification techniques studied in this work include water extraction, isotope exchange, adsorption, and distillation. These laboratory studies guided the design and implementation of a large scale purification system in the Kamioka mine. The purification system's design and operation is discussed in detail as well as specific experiments devised to control scintillator quality and radio-purity. The purification system's effectiveness in removing radioactive trace impurities is analyzed in detail. The total scintillator purified over two

  9. Measurement of the solar neutrino capture rate with gallium metal, part III

    SciTech Connect

    Elliott, Steven Ray

    2008-01-01

    The Russian-American experiment SAGE began to measure the solar neutrino capture rate with a target of gallium metal in December 1989. Measurements have continued with only a few brief interruptions since that time. In this article we present the experimental improvements in SAGE since its last published data summary in December 2001. Assuming the solar neutrino production rate was constant during the period of data collection, combined analysis of 168 extractions through December 2007 gives a capture rate of solar neutrinos with energy more than 233 keY of 65.4{sup +3.1}{sub 3.0} (stat) {sup +2.6}{sub -2.8} (syst) SNU. The weighted average of the results of all three Ga solar neUlrino experiments, SAGE, Gallex, and GNO, is now 66.1 {+-} 3.1 SNU, where statistical and systematic uncertainties have been combined in quadrature. During the recent period of data collection a new test of SAGE was made with a reactor-produced {sup 37}Ar neutrino source. The ratio of observed to calculated rates in this experiment, combined with the measured rates in the three prior {sup 51}Cr neutrino-source experiments with Ga, is 0.88 {+-} 0.05. A probable explanation for this low result is that the cross section for neutrino capture by the two lowest-lying excited states in {sup 71}Ge has been overestimated. If we assume these cross sections are zero, then the standard solar model including neutrino oscillations predicts a total capture rate in Ga in the range of 63--67 SNU with an uncertainly of about 5%, in good agreement with experiment. We derive the current value of the pp neutrino flux produced in the Sun to be {phi}{sup {circle_dot}}{sub pp} = (6.1 {+-} 0.8) x 10{sup 10}/(cm{sup 2} s), which agrees well with the flux predicted by the standard solar model. Finally, we make several tests and show that the data are consistent with the assumption that the solar neutrino production rate is constant in time.

  10. Studying the Sun's Nuclear Furnace with a Neutrino Detector Spacecraft in Close Solar Orbit

    NASA Astrophysics Data System (ADS)

    Solomey, Nickolas

    2016-05-01

    A neutrino based detector in close solar orbit would have a neutrino flux 10,000x or more larger flux than on Earth and a smaller detector able to handle high rates with exception energy resolution could be used. We have studied the idea of operating such an experiment in close solar orbits that takes it off the ecliptic plane and in a solar orbit where the distance from the Sun will change distance. This neutrino detector on a space craft could do Solar Astrophysics studying the Solar nuclear furnace, basic nuclear physics and elementary particle physics; some of these ideas are new unique science that can only be preformed from a spacecraft. The harsh environment provides many challenges but if such a detector could be made to work it can be the next major step in this science study. How a small segmented detector can operate and preform in this environment to detect solar neutrinos will be elaborated upon using a combination of signal strength, fast signal timing, shielding and segmentation.

  11. THE SOLAR ENERGETIC BALANCE REVISITED BY YOUNG SOLAR ANALOGS, HELIOSEISMOLOGY, AND NEUTRINOS

    SciTech Connect

    Turck-Chieze, Sylvaine; Piau, Laurent

    2011-04-20

    The energetic balance of the standard solar model (SSM) results from equilibrium between nuclear energy production, energy transfer, and photospheric emission. In this Letter, we give an order of magnitude of several percent for the loss of energy in kinetic energy, magnetic energy, and X-ray or UV radiation during the entire solar lifetime from the observations of the present Sun. We also estimate the loss of mass from the observations of young solar analogs, which could reach up to 30%. We deduce new models of the present Sun, their associated neutrino fluxes, and internal sound-speed profile. This approach sheds quantitative lights on the disagreement between the sound speed obtained by helioseismology and the sound speed derived from the SSM including the updated photospheric CNO abundances, based on recent observations. We conclude that about 20% of the present discrepancy could come from the incorrect description of the early phases of the Sun, its activity, its initial mass, and mass-loss history. This study has obvious consequences on the solar system formation and the early evolution of the closest planets.

  12. Solar oscillations, gravitational multipole field of the sun and the solar neutrino paradox

    SciTech Connect

    Hill, H.A.; Rosenwald, R.D.

    1986-11-04

    The visual solar oblateness work and the solar seismological work on the internal rotation of the sun are reviewed and their implications concerning the static gravitational multipole moments of the sun are discussed. The results of this work are quite deviant which is indicative of the complexity encountered and of the necessity for continued studies based on a diverse set of observing techniques. The evidence for phase-locked internal gravity modes of the sun is reviewed and the implications for the solar neutrino paradox are discussed. The rather unique possibility for testing the relevance which the phase-locked gravity modes have to this paradox is also noted. The oscillating perturbations in the sun's gravitational field produced by the classified internal gravity modes and the phase-locked modes are inferred from the observed temperature eigenfunctions. Strains of the order of 10/sup -18/ in gravitational radiation detectors based on free masses are inferred for frequencies near 100 ..mu..Hz. The relevance of these findings is discussed in terms of a new technique for use in solar seismological studies and of producing background signals in studies of low-frequency gravitational radiation. 64 refs., 2 figs.

  13. Neutrinos

    NASA Astrophysics Data System (ADS)

    Winter, K.; Murdin, P.

    2000-11-01

    Neutrinos are electrically neutral ELEMENTARY PARTICLES which experience only the weak nuclear force and gravity. Their existence was introduced as a hypothesis by Wolfgang Pauli in 1930 to explain the apparent violation of energy conservation in radioactive beta decay. Chadwick had discovered in 1914 that the energy spectrum of electrons emitted in beta decay was not monoenergetic but continuous...

  14. Solar neutrinos and the influences of opacity, thermal instability, additional neutrino sources, and a central black hole on solar models

    NASA Technical Reports Server (NTRS)

    Stothers, R. B.; Ezer, D.

    1972-01-01

    Significant quantities that affect the internal structure of the sun are examined for factors that reduce the temperature near the sun's center. The four factors discussed are: opacity, central black hole, thermal instability, and additional neutrino sources.

  15. A Study of Solar Neutrinos Using the Super-Kamiokande Detector

    NASA Astrophysics Data System (ADS)

    Conner, Zoa

    The first solar neutrino flux results from the Super-Kamiokande detector are described. This independent analysis is based on a data set from June 1996 through February 1997. A total neutrino flux of 2.61 ± 0.12 (stat) ±0.13 (syst) ×106/ [ν over cm2s] is implied from the data above a 7 MeV energy threshold. When the measurement is compared with the most recent Standard Solar Model flux prediction (BP95), the ratio of data/SSM is 0.394 ± 0.018 (stat) ± 0.019 (syst). The measured fluxes during day and night yield a fractional difference of +0.019 ± 0.046 (stat). Interpretations are given in the context of vacuum and MSW enhanced neutrino flavor oscillations.

  16. Proton decay and solar neutrino experiment with a liquid argon Time Projection Chamber

    SciTech Connect

    Chen, H.H.; Doe, P.J.; Mahler, H.I.

    1983-01-01

    Recent progress in development of the liquid argon Time Projection Chamber is reviewed. Application of this technique to a search for proton decay and /sup 8/B solar neutrinos with directional sensitivity is considered. The steps necessary for a large scale application of this technique deep underground are described.

  17. Proposed solar neutrino experiment using /sup 81/Br(nu,e/sup -/)/sup 81/Kr

    SciTech Connect

    Hurst, G.S.; Chen, C.H.; Kramer, S.D.; Allman, S.L.

    1984-12-01

    It has now been shown that it is feasible to measure the /sup 7/Be neutrino source in the sun by using the reaction /sup 81/Br(nu,e/sup -/)/sup 81/Kr in a radiochemical experiment. Such an experiment would be quite similar to the Davis, Cleveland, and Rowley method for measuring the /sup 8/B neutrino using /sup 37/Cl(nu,e/sup -/)/sup 37/Ar except that the resonance ionization spectroscopy (RIS) method (instead of decay counting) would be employed to count the 2 x 10/sup 5/-yr /sup 81/Kr atoms.

  18. Solar neutrino limit on axions and keV-mass bosons

    SciTech Connect

    Gondolo, Paolo; Raffelt, Georg G.

    2009-05-15

    The all-flavor solar neutrino flux measured by the Sudbury Neutrino Observatory constrains nonstandard energy losses to less than about 10% of the Sun's photon luminosity, superseding a helioseismological argument and providing new limits on the interaction strength of low-mass particles. For the axion-photon coupling strength we find g{sub a{gamma}}<7x10{sup -10} GeV{sup -1}. We also derive explicit limits on the Yukawa coupling to electrons of pseudoscalar, scalar, and vector bosons with keV-scale masses.

  19. Independent Measurement of the Total Active B8 Solar Neutrino Flux Using an Array of He3 Proportional Counters at the Sudbury Neutrino Observatory

    NASA Astrophysics Data System (ADS)

    Aharmim, B.; Ahmed, S. N.; Amsbaugh, J. F.; Anthony, A. E.; Banar, J.; Barros, N.; Beier, E. W.; Bellerive, A.; Beltran, B.; Bergevin, M.; Biller, S. D.; Boudjemline, K.; Boulay, M. G.; Bowles, T. J.; Browne, M. C.; Bullard, T. V.; Burritt, T. H.; Cai, B.; Chan, Y. D.; Chauhan, D.; Chen, M.; Cleveland, B. T.; Cox-Mobrand, G. A.; Currat, C. A.; Dai, X.; Deng, H.; Detwiler, J.; Dimarco, M.; Doe, P. J.; Doucas, G.; Drouin, P.-L.; Duba, C. A.; Duncan, F. A.; Dunford, M.; Earle, E. D.; Elliott, S. R.; Evans, H. C.; Ewan, G. T.; Farine, J.; Fergani, H.; Fleurot, F.; Ford, R. J.; Formaggio, J. A.; Fowler, M. M.; Gagnon, N.; Germani, J. V.; Goldschmidt, A.; Goon, J. T. M.; Graham, K.; Guillian, E.; Habib, S.; Hahn, R. L.; Hallin, A. L.; Hallman, E. D.; Hamian, A. A.; Harper, G. C.; Harvey, P. J.; Hazama, R.; Heeger, K. M.; Heintzelman, W. J.; Heise, J.; Helmer, R. L.; Henning, R.; Hime, A.; Howard, C.; Howe, M. A.; Huang, M.; Jagam, P.; Jamieson, B.; Jelley, N. A.; Keeter, K. J.; Klein, J. R.; Kormos, L. L.; Kos, M.; Krüger, A.; Kraus, C.; Krauss, C. B.; Kutter, T.; Kyba, C. C. M.; Lange, R.; Law, J.; Lawson, I. T.; Lesko, K. T.; Leslie, J. R.; Loach, J. C.; MacLellan, R.; Majerus, S.; Mak, H. B.; Maneira, J.; Martin, R.; McBryde, K.; McCauley, N.; McDonald, A. B.; McGee, S.; Mifflin, C.; Miller, G. G.; Miller, M. L.; Monreal, B.; Monroe, J.; Morissette, B.; Myers, A.; Nickel, B. G.; Noble, A. J.; Oblath, N. S.; O'Keeffe, H. M.; Ollerhead, R. W.; Gann, G. D. Orebi; Oser, S. M.; Ott, R. A.; Peeters, S. J. M.; Poon, A. W. P.; Prior, G.; Reitzner, S. D.; Rielage, K.; Robertson, B. C.; Robertson, R. G. H.; Rollin, E.; Schwendener, M. H.; Secrest, J. A.; Seibert, S. R.; Simard, O.; Simpson, J. J.; Sinclair, L.; Skensved, P.; Smith, M. W. E.; Steiger, T. D.; Stonehill, L. C.; Tešić, G.; Thornewell, P. M.; Tolich, N.; Tsui, T.; Tunnell, C. D.; van Wechel, T.; van Berg, R.; Vandevender, B. A.; Virtue, C. J.; Walker, T. J.; Wall, B. L.; Waller, D.; Tseung, H. Wan Chan; Wendland, J.; West, N.; Wilhelmy, J. B.; Wilkerson, J. F.; Wilson, J. R.; Wouters, J. M.; Wright, A.; Yeh, M.; Zhang, F.; Zuber, K.

    2008-09-01

    The Sudbury Neutrino Observatory (SNO) used an array of He3 proportional counters to measure the rate of neutral-current interactions in heavy water and precisely determined the total active (νx) B8 solar neutrino flux. This technique is independent of previous methods employed by SNO. The total flux is found to be 5.54-0.31+0.33(stat)-0.34+0.36(syst)×106cm-2s-1, in agreement with previous measurements and standard solar models. A global analysis of solar and reactor neutrino results yields Δm2=7.59-0.21+0.19×10-5eV2 and θ=34.4-1.2+1.3 degrees. The uncertainty on the mixing angle has been reduced from SNO’s previous results.

  20. Independent measurement of the total active 8B solar neutrino flux using an array of 3He proportional counters at the Sudbury Neutrino Observatory.

    PubMed

    Aharmim, B; Ahmed, S N; Amsbaugh, J F; Anthony, A E; Banar, J; Barros, N; Beier, E W; Bellerive, A; Beltran, B; Bergevin, M; Biller, S D; Boudjemline, K; Boulay, M G; Bowles, T J; Browne, M C; Bullard, T V; Burritt, T H; Cai, B; Chan, Y D; Chauhan, D; Chen, M; Cleveland, B T; Cox-Mobrand, G A; Currat, C A; Dai, X; Deng, H; Detwiler, J; DiMarco, M; Doe, P J; Doucas, G; Drouin, P-L; Duba, C A; Duncan, F A; Dunford, M; Earle, E D; Elliott, S R; Evans, H C; Ewan, G T; Farine, J; Fergani, H; Fleurot, F; Ford, R J; Formaggio, J A; Fowler, M M; Gagnon, N; Germani, J V; Goldschmidt, A; Goon, J T M; Graham, K; Guillian, E; Habib, S; Hahn, R L; Hallin, A L; Hallman, E D; Hamian, A A; Harper, G C; Harvey, P J; Hazama, R; Heeger, K M; Heintzelman, W J; Heise, J; Helmer, R L; Henning, R; Hime, A; Howard, C; Howe, M A; Huang, M; Jagam, P; Jamieson, B; Jelley, N A; Keeter, K J; Klein, J R; Kormos, L L; Kos, M; Krüger, A; Kraus, C; Krauss, C B; Kutter, T; Kyba, C C M; Lange, R; Law, J; Lawson, I T; Lesko, K T; Leslie, J R; Loach, J C; MacLellan, R; Majerus, S; Mak, H B; Maneira, J; Martin, R; McBryde, K; McCauley, N; McDonald, A B; McGee, S; Mifflin, C; Miller, G G; Miller, M L; Monreal, B; Monroe, J; Morissette, B; Myers, A; Nickel, B G; Noble, A J; Oblath, N S; O'Keeffe, H M; Ollerhead, R W; Gann, G D Orebi; Oser, S M; Ott, R A; Peeters, S J M; Poon, A W P; Prior, G; Reitzner, S D; Rielage, K; Robertson, B C; Robertson, R G H; Rollin, E; Schwendener, M H; Secrest, J A; Seibert, S R; Simard, O; Simpson, J J; Sinclair, L; Skensved, P; Smith, M W E; Steiger, T D; Stonehill, L C; Tesić, G; Thornewell, P M; Tolich, N; Tsui, T; Tunnell, C D; Van Wechel, T; Van Berg, R; VanDevender, B A; Virtue, C J; Walker, T J; Wall, B L; Waller, D; Tseung, H Wan Chan; Wendland, J; West, N; Wilhelmy, J B; Wilkerson, J F; Wilson, J R; Wouters, J M; Wright, A; Yeh, M; Zhang, F; Zuber, K

    2008-09-12

    The Sudbury Neutrino Observatory (SNO) used an array of 3He proportional counters to measure the rate of neutral-current interactions in heavy water and precisely determined the total active (nu_x) 8B solar neutrino flux. This technique is independent of previous methods employed by SNO. The total flux is found to be 5.54_-0.31;+0.33(stat)-0.34+0.36(syst)x10(6) cm(-2) s(-1), in agreement with previous measurements and standard solar models. A global analysis of solar and reactor neutrino results yields Deltam2=7.59_-0.21;+0.19x10(-5) eV2 and theta=34.4_-1.2;+1.3 degrees. The uncertainty on the mixing angle has been reduced from SNO's previous results.

  1. Independent measurement of the total active 8B solar neutrino flux using an array of 3He proportional counters at the Sudbury Neutrino Observatory.

    PubMed

    Aharmim, B; Ahmed, S N; Amsbaugh, J F; Anthony, A E; Banar, J; Barros, N; Beier, E W; Bellerive, A; Beltran, B; Bergevin, M; Biller, S D; Boudjemline, K; Boulay, M G; Bowles, T J; Browne, M C; Bullard, T V; Burritt, T H; Cai, B; Chan, Y D; Chauhan, D; Chen, M; Cleveland, B T; Cox-Mobrand, G A; Currat, C A; Dai, X; Deng, H; Detwiler, J; DiMarco, M; Doe, P J; Doucas, G; Drouin, P-L; Duba, C A; Duncan, F A; Dunford, M; Earle, E D; Elliott, S R; Evans, H C; Ewan, G T; Farine, J; Fergani, H; Fleurot, F; Ford, R J; Formaggio, J A; Fowler, M M; Gagnon, N; Germani, J V; Goldschmidt, A; Goon, J T M; Graham, K; Guillian, E; Habib, S; Hahn, R L; Hallin, A L; Hallman, E D; Hamian, A A; Harper, G C; Harvey, P J; Hazama, R; Heeger, K M; Heintzelman, W J; Heise, J; Helmer, R L; Henning, R; Hime, A; Howard, C; Howe, M A; Huang, M; Jagam, P; Jamieson, B; Jelley, N A; Keeter, K J; Klein, J R; Kormos, L L; Kos, M; Krüger, A; Kraus, C; Krauss, C B; Kutter, T; Kyba, C C M; Lange, R; Law, J; Lawson, I T; Lesko, K T; Leslie, J R; Loach, J C; MacLellan, R; Majerus, S; Mak, H B; Maneira, J; Martin, R; McBryde, K; McCauley, N; McDonald, A B; McGee, S; Mifflin, C; Miller, G G; Miller, M L; Monreal, B; Monroe, J; Morissette, B; Myers, A; Nickel, B G; Noble, A J; Oblath, N S; O'Keeffe, H M; Ollerhead, R W; Gann, G D Orebi; Oser, S M; Ott, R A; Peeters, S J M; Poon, A W P; Prior, G; Reitzner, S D; Rielage, K; Robertson, B C; Robertson, R G H; Rollin, E; Schwendener, M H; Secrest, J A; Seibert, S R; Simard, O; Simpson, J J; Sinclair, L; Skensved, P; Smith, M W E; Steiger, T D; Stonehill, L C; Tesić, G; Thornewell, P M; Tolich, N; Tsui, T; Tunnell, C D; Van Wechel, T; Van Berg, R; VanDevender, B A; Virtue, C J; Walker, T J; Wall, B L; Waller, D; Tseung, H Wan Chan; Wendland, J; West, N; Wilhelmy, J B; Wilkerson, J F; Wilson, J R; Wouters, J M; Wright, A; Yeh, M; Zhang, F; Zuber, K

    2008-09-12

    The Sudbury Neutrino Observatory (SNO) used an array of 3He proportional counters to measure the rate of neutral-current interactions in heavy water and precisely determined the total active (nu_x) 8B solar neutrino flux. This technique is independent of previous methods employed by SNO. The total flux is found to be 5.54_-0.31;+0.33(stat)-0.34+0.36(syst)x10(6) cm(-2) s(-1), in agreement with previous measurements and standard solar models. A global analysis of solar and reactor neutrino results yields Deltam2=7.59_-0.21;+0.19x10(-5) eV2 and theta=34.4_-1.2;+1.3 degrees. The uncertainty on the mixing angle has been reduced from SNO's previous results. PMID:18851271

  2. Chasing the ghost particle: The long and winding road toward the detection of solar neutrinos

    NASA Astrophysics Data System (ADS)

    Leone, Matteo; Robotti, Nadia

    2015-10-01

    One of the great achievements of neutrino physics was the discovery of solar neutrinos in 1968 through the Homestake underground experiment. This experiment exploited a radiochemical method based on the chlorine-argon process of inverse beta decay suggested by Bruno Pontecorvo in 1946 during his work in the classified Canadian nuclear project. In this paper, we study the emergence of the method. We focus on the role played by the problematic status of the neutrino and its antiparticle in its field of application and the influence exerted by the contemporary models of energy production in the sun. We also provide evidence that a first germ of this radiochemical method, in the form of a chlorine-sulfur process, was suggested in a paper published by Richard Crane in late 1930s.

  3. A search for evidence of solar rotation in Super-Kamiokande solar neutrino dataset

    NASA Astrophysics Data System (ADS)

    Desai, Shantanu; Liu, Dawei W.

    2016-09-01

    We apply the generalized Lomb-Scargle (LS) periodogram, proposed by Zechmeister and Kurster, to the solar neutrino data from Super-Kamiokande (Super-K) using data from its first five years. For each peak in the LS periodogram, we evaluate the statistical significance in two different ways. The first method involves calculating the False Alarm Probability (FAP) using non-parametric bootstrap resampling, and the second method is by calculating the difference in Bayesian Information Criterion (BIC) between the null hypothesis, viz. the data contains only noise, compared to the hypothesis that the data contains a peak at a given frequency. Using these methods, we scan the frequency range between 7-14 cycles per year to look for any peaks caused by solar rotation, since this is the proposed explanation for the statistically significant peaks found by Sturrock and collaborators in the Super-K dataset. From our analysis, we do confirm that similar to Sturrock et al, the maximum peak occurs at a frequency of 9.42/year, corresponding to a period of 38.75 days. The FAP for this peak is about 1.5% and the difference in BIC (between pure white noise and this peak) is about 4.8. We note that the significance depends on the frequency band used to search for peaks and hence it is important to use a search band appropriate for solar rotation. However, The significance of this peak based on the value of BIC is marginal and more data is needed to confirm if the peak persists and is real.

  4. Proton resonance scattering of 7Be

    SciTech Connect

    Yamaguchi, H.; Saito, A.; He, J. J.; Wakabayashi, Y.; Amadio, G.; Fujikawa, H.; Kubono, S.; Khiem, L. H.; Niikura, M.; Kwon, Y. K.; Teranishi, T.; Nishimura, S.; Togano, Y.; Iwasa, N.; Inafuku, K.

    2006-07-12

    We have studied the proton resonance scattering of 7Be by using a pure 7Be beam produced at CRIB (CNS Radioactive Ion Beam separator; CNS stands for Center of Nuclear Study, University of Tokyo). The excitation function of 8B was measured up to the excitation energy of 6.8 MeV, with the thick-target method. The excited states of 8B higher than 3.5 MeV were not known by the past experiments. This proton elastic scattering is also of importance in relation with the 7Be(p,{gamma})8B reaction, which is a key reaction in the standard solar model.

  5. Proton resonance scattering of 7Be

    NASA Astrophysics Data System (ADS)

    Yamaguchi, H.; Saito, A.; He, J. J.; Wakabayashi, Y.; Amadio, G.; Fujikawa, H.; Kubono, S.; Khiem, L. H.; Kwon, Y. K.; Niikura, M.; Teranishi, T.; Nishimura, S.; Togano, Y.; Iwasa, N.; Inafuku, K.

    2006-07-01

    We have studied the proton resonance scattering of 7Be by using a pure 7Be beam produced at CRIB (CNS Radioactive Ion Beam separator; CNS stands for Center of Nuclear Study, University of Tokyo). The excitation function of 8B was measured up to the excitation energy of 6.8 MeV, with the thick-target method. The excited states of 8B higher than 3.5 MeV were not known by the past experiments. This proton elastic scattering is also of importance in relation with the 7Be(p,γ)8B reaction, which is a key reaction in the standard solar model.

  6. Measurement of the rate of nu(e) + d --> p + p + e(-) interactions produced by (8)B solar neutrinos at the Sudbury Neutrino Observatory.

    PubMed

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

    2001-08-13

    Solar neutrinos from (8)B decay have been detected at the Sudbury Neutrino Observatory via the charged current (CC) reaction on deuterium and the elastic scattering (ES) of electrons. The flux of nu(e)'s is measured by the CC reaction rate to be straight phi(CC)(nu(e)) = 1.75 +/- 0.07(stat)(+0.12)(-0.11)(syst) +/- 0.05(theor) x 10(6) cm(-2) s(-1). Comparison of straight phi(CC)(nu(e)) to the Super-Kamiokande Collaboration's precision value of the flux inferred from the ES reaction yields a 3.3 sigma difference, assuming the systematic uncertainties are normally distributed, providing evidence of an active non- nu(e) component in the solar flux. The total flux of active 8B neutrinos is determined to be 5.44+/-0.99 x 10(6) cm(-2) s(-1).

  7. Detecting electron neutrinos from solar dark matter annihilation by JUNO

    NASA Astrophysics Data System (ADS)

    Guo, Wan-Lei

    2016-01-01

    We explore the electron neutrino signals from light dark matter (DM) annihilation in the Sun for the large liquid scintillator detector JUNO. In terms of the spectrum features of three typical DM annihilation channels χχ → νbar nu, τ+τ-, bbar b, we take two sets of selection conditions to calculate the expected signals and atmospheric neutrino backgrounds based on the Monte Carlo simulation data. Then the JUNO sensitivities to the spin independent DM-nucleon and spin dependent DM-proton cross sections are presented. It is found that the JUNO projected sensitivities are much better than the current spin dependent direct detection experimental limits for the νbar nu and τ+τ- channels. In the spin independent case, the JUNO will give the better sensitivity to the DM-nucleon cross section than the LUX and CDMSlite limits for the νbar nu channel with the DM mass lighter than 6.5 GeV . If the νbar nu or τ+τ- channel is dominant, the future JUNO results are very helpful for us to understand the tension between the DAMA annual modulation signal and other direct detection exclusions.

  8. Detecting electron neutrinos from solar dark matter annihilation by JUNO

    SciTech Connect

    Guo, Wan-Lei

    2016-01-01

    We explore the electron neutrino signals from light dark matter (DM) annihilation in the Sun for the large liquid scintillator detector JUNO. In terms of the spectrum features of three typical DM annihilation channels χχ → νν-bar , τ{sup +}τ{sup −}, b b-bar , we take two sets of selection conditions to calculate the expected signals and atmospheric neutrino backgrounds based on the Monte Carlo simulation data. Then the JUNO sensitivities to the spin independent DM-nucleon and spin dependent DM-proton cross sections are presented. It is found that the JUNO projected sensitivities are much better than the current spin dependent direct detection experimental limits for the νν-bar and τ{sup +}τ{sup −} channels. In the spin independent case, the JUNO will give the better sensitivity to the DM-nucleon cross section than the LUX and CDMSlite limits for the νν-bar channel with the DM mass lighter than 6.5 GeV . If the νν-bar or τ{sup +}τ{sup −} channel is dominant, the future JUNO results are very helpful for us to understand the tension between the DAMA annual modulation signal and other direct detection exclusions.

  9. Production and suppression of {sup 11}C in the solar neutrino experiment Borexino

    SciTech Connect

    Meindl, Quirin; Bellini, G.; Benziger, J.; Bonetti, S.; Avanzini, M. Buizza; Caccianiga, B.; Cadonati, L.; Calaprice, F.; Carraro, C.; Chavarria, A.; Chepurnov, A.; Dalnoki-Veress, F.; D'Angelo, D.; Davini, S.; Kerret, H. de; Derbin, A.; Etenko, A.; Feilitzsch, F. von; Fomenko, K.; Franco, D.

    2011-04-27

    Cosmogenic {sup 11}C is produced in-situ by atmospheric muons and forms the main background for the measurement of solar pep- and CNO-neutrinos. However, FLUKA simulations show that the majority of {sup 11}C is accompanied by a free neutron in the final state, thus allowing for an efficient tagging method, the so-called Three-Fold Coincidence technique. The technique and its first applications on Borexino data are presented.

  10. Production and suppression of 11C in the solar neutrino experiment Borexino

    NASA Astrophysics Data System (ADS)

    Meindl, Quirin; Bellini, G.; Benziger, J.; Bonetti, S.; Avanzini, M. Buizza; Caccianiga, B.; Cadonati, L.; Calaprice, F.; Carraro, C.; Chavarria, A.; Chepurnov, A.; Dalnoki-Veress, F.; D'Angelo, D.; Davini, S.; de Kerret, H.; Derbin, A.; Etenko, A.; von Feilitzsch, F.; Fomenko, K.; Franco, D.; Galbiati, C.; Gazzana, S.; Ghiano, C.; Giammarchi, M.; Goeger-Neff, M.; Goretti, A.; Guardincerri, E.; Hardy, S.; Ianni, Aldo; Ianni, Andrea; Joyce, M.; Kobychev, V.; Korga, G.; Kryn, D.; Laubenstein, M.; Leung, M.; Lewke, T.; Litvinovich, E.; Loer, B.; Lombardi, P.; Ludhova, L.; Machulin, I.; Manecki, S.; Maneschg, W.; Manuzio, G.; Meindl, Q.; Meroni, E.; Miramonti, L.; Misiaszek, M.; Montanari, D.; Muratova, V.; Oberauer, L.; Obolensky, M.; Ortica, F.; Pallavicini, M.; Papp, L.; Perasso, L.; Perasso, S.; Pocar, A.; Raghavan, R. S.; Ranucci, G.; Razeto, A.; Re, A.; Risso, P.; Romani, A.; Rountree, D.; Sabelnikov, A.; Saldanha, R.; Salvo, C.; Schönert, S.; Simgen, H.; Skorokhvatov, M.; Smirnov, O.; Sotnikov, A.; Sukhotin, S.; Suvorov, Y.; Tartaglia, R.; Testera, G.; Vignaud, D.; Vogelaar, R. B.; Winter, J.; Wojcik, M.; Wright, A.; Wurm, M.; Xu, J.; Zaimidoroga, O.; Zavatarelli, S.; Zuzel, G.

    2011-04-01

    Cosmogenic 11C is produced in-situ by atmospheric muons and forms the main background for the measurement of solar pep- and CNO-neutrinos. However, FLUKA simulations show that the majority of 11C is accompanied by a free neutron in the final state, thus allowing for an efficient tagging method, the so-called Three-Fold Coincidence technique. The technique and its first applications on Borexino data are presented.

  11. SEISMIC AND DYNAMICAL SOLAR MODELS. I. THE IMPACT OF THE SOLAR ROTATION HISTORY ON NEUTRINOS AND SEISMIC INDICATORS

    SciTech Connect

    Turck-Chieze, S.; Palacios, A.; Nghiem, P. A. P.

    2010-06-01

    Solar activity and helioseismology show the limitation of the standard solar model and call for the inclusion of dynamical processes in both convective and radiative zones. In this paper, we concentrate on the radiative zone. We first recall the sensitivity of boron neutrinos to the microscopic physics included in solar standard and seismic models. We confront the neutrino predictions of the seismic model with all the detected neutrino fluxes. Then, we compute new models of the Sun including a detailed transport of angular momentum and chemicals due to internal rotation that includes meridional circulation and shear-induced turbulence. We use two stellar evolution codes: CESAM and STAREVOL to estimate the different terms. We follow three temporal evolutions of the internal rotation which differ by their initial conditions: very slow, moderate, and fast rotation, with magnetic braking at the arrival on the main sequence for the last two. We find that the meridional velocities in the present solar radiative zone are extremely small in comparison with those of the convective zone (smaller than 10{sup -6} cm s{sup -1} instead of m s{sup -1}). All models lead to a radial differential rotation profile in the radiative zone but with a significantly different contrast. We compare these profiles to the presumed solar internal rotation and show that if meridional circulation and shear turbulence were the only mechanisms transporting angular momentum within the Sun, a rather slow rotation in the young Sun is favored. We confirm the small influence of the transport by rotation on the sound speed profile but its potential impact on the chemicals in the transition region between radiation and convective zones. These models are physically more representative of the real Sun than the standard or seismic solar models but a high initial rotation, as has been considered previously, increases the disagreement with neutrinos and the sound speed in the radiative zone. This present work

  12. Neutrino masses, neutrino oscillations, and cosmological implications

    NASA Technical Reports Server (NTRS)

    Stecker, F. W.

    1982-01-01

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

  13. Effects of heavy-element settling on solar neutrino fluxes and interior structure

    NASA Technical Reports Server (NTRS)

    Proffitt, Charles R.

    1994-01-01

    We consider the effects of gravitational settling of both He and heavier elements on the predicted solar neutrino fluxes and interior sound speed and density profiles. We find that while the structural changes that result from the inclusion of both He and heavy-element settling are only slightly larger than the changes resulting from the inclusion of He settling alone, the additional increases in expected neutrino fluxes are of comparable size. Our preferred model with both He and heavy-element settling has neutrino count rates of 9.0 SNU for Cl-37 detectors and 137 SNU for Ga-71 detectors, as compared to 7.1 and 127 SNU for a comparable model without any diffusive separation, or 8.0 and 132 SNU for a model that includes He settling alone. We suggest that the correction factors by which the predicted neutrino fluxes of solar models calculated without including the effects of diffusion should be multiplied are 1.25 +/- 0.08 for Cl detectors, 1.07 +/- 0.02 for Ga detectors, and 1.28 +/- 0.09 for the B-8 flux (1 sigma errors). Comparison of internal sound speed and density profiles strongly suggests that the additional changes in calculated p-mode oscillation frequencies due to the inclusion of heavy-element settling will be small compared to the changes that result from He settling alone, especially for the higher degree modes. All models with diffusive separation give much better agreement with the observed depth of the convection zone than do nondiffusive models. The model that includes both He and heavy-element settling requires an initial He mass fraction Y = 0.280 and has a surface He abundance of Y = 0.251 at the solar age.

  14. Nuclear Structure of 8B Studied by Proton Resonance Scatterings on 7Be

    NASA Astrophysics Data System (ADS)

    Yamaguchi, H.; Wakabayashi, Y.; Hayakawa, S.; Amadio, G.; Kubono, S.; Fujikawa, H.; Saito, A.; He, J. J.; Teranishi, T.; Kwon, Y. K.; Nishimura, S.; Togano, Y.; Iwasa, N.; Inafuku, K.; Niikura, M.; Binh, D. N.; Khiem, L. H.

    2008-05-01

    A new measurement of the proton resonance scattering on 7Be was performed up to the excitation energy of 6.8 MeV using the low-energy RI beam facility CRIB (CNS Radioactive Ion Beam separator) at the Center for Nuclear Study (CNS) of the University of Tokyo. The excitation function of 8B above 3.5 MeV was successfully measured for the first time, providing important information about the reaction rate of 7Be(p,γ)8B, which is the key reaction in the solar 8B neutrino production. For more intensive experimental studies with RI beams, the development of a cryogenic gas target system is ongoing at CNS. In this paper a preliminary result of the 7Be experiment and the present status of the development of the target system are presented.

  15. Nuclear Structure of {sup 8}B Studied by Proton Resonance Scatterings on {sup 7}Be

    SciTech Connect

    Yamaguchi, H.; Wakabayashi, Y.; Hayakawa, S.; Amadio, G.; Kubono, S.; Fujikawa, H.; Niikura, M.; Binh, D. N.; Saito, A.; He, J. J.; Teranishi, T.; Kwon, Y. K.; Nishimura, S.; Togano, Y.; Iwasa, N.; Inafuku, K.; Khiem, L. H.

    2008-05-21

    A new measurement of the proton resonance scattering on {sup 7}Be was performed up to the excitation energy of 6.8 MeV using the low-energy RI beam facility CRIB (CNS Radioactive Ion Beam separator) at the Center for Nuclear Study (CNS) of the University of Tokyo. The excitation function of {sup 8}B above 3.5 MeV was successfully measured for the first time, providing important information about the reaction rate of {sup 7}Be(p,{gamma}){sup 8}B, which is the key reaction in the solar {sup 8}B neutrino production. For more intensive experimental studies with RI beams, the development of a cryogenic gas target system is ongoing at CNS. In this paper a preliminary result of the {sup 7}Be experiment and the present status of the development of the target system are presented.

  16. Measurement of the {sup 8}B solar neutrino flux with the KamLAND liquid scintillator detector

    SciTech Connect

    Abe, S.; Furuno, K.; Gando, A.; Gando, Y.; Ichimura, K.; Ikeda, H.; Kibe, Y.; Kimura, W.; Kishimoto, Y.; Minekawa, Y.; Mitsui, T.; Morikawa, T.; Nagai, N.; Nakajima, K.; Nakamura, M.; Narita, K.; Shimizu, I.; Shimizu, Y.; Shirai, J.; Suekane, F.

    2011-09-15

    We report a measurement of the neutrino-electron elastic scattering rate from {sup 8}B solar neutrinos based on a 123 kton-day exposure of KamLAND. The background-subtracted electron recoil rate, above a 5.5-MeV analysis threshold is 1.49 {+-} 0.14(stat) {+-} 0.17(syst) events per kton-day. Interpreted as due to a pure electron flavor flux with a {sup 8}B neutrino spectrum, this corresponds to a spectrum integrated flux of 2.77 {+-} 0.26(stat) {+-} 0.32(syst) x10{sup 6} cm{sup -2}s{sup -1}. The analysis threshold is driven by {sup 208}Tl present in the liquid scintillator, and the main source of systematic uncertainty is due to background from cosmogenic {sup 11}Be. The measured rate is consistent with existing measurements and with standard solar model predictions which include matter-enhanced neutrino oscillation.

  17. Neutrino Detectors

    NASA Astrophysics Data System (ADS)

    von Feilitzsch, Franz; Lanfranchi, Jean-Côme; Wurm, Michael

    The neutrino was postulated by Wolfgang Pauli in the early 1930s, but could only be detected for the first time in the 1950s. Ever since scientists all around the world have worked on the detection and understanding of this particle which so scarcely interacts with matter. Depending on the origin and nature of the neutrino, various types of experiments have been developed and operated. In this entry, we will review neutrino detectors in terms of neutrino energy and associated detection technique as well as the scientific outcome of some selected examples. After a brief historical introduction, the detection of low-energy neutrinos originating from nuclear reactors or from the Earth is used to illustrate the principles and difficulties which are encountered in detecting neutrinos. In the context of solar neutrino spectroscopy, where the neutrino is used as a probe for astrophysics, three different types of neutrino detectors are presented - water Čerenkov, radiochemical, and liquid-scintillator detectors. Moving to higher neutrino energies, we discuss neutrinos produced by astrophysical sources and from accelerators. The entry concludes with an overview of a selection of future neutrino experiments and their scientific goals.

  18. Results of ultra-low level 71ge counting for application in the Gallex-solar neutrino experiment at the Gran Sasso Underground Physics Laboratory

    NASA Technical Reports Server (NTRS)

    Hampel, W.; Heusser, G.; Huebner, M.; Kiko, J.; Kirsten, T.; Schneider, K.; Schlotz, R.

    1985-01-01

    It has been experimentally verified that the Ultra-Low-Level Counting System for the Gallex solar neutrino experiment is capable of measuring the expected solar up silon-flux to plus or minus 12% during two years of operation.

  19. FIRST STUDY OF DARK MATTER PROPERTIES WITH DETECTED SOLAR GRAVITY MODES AND NEUTRINOS

    SciTech Connect

    Turck-Chieze, S.; Garcia, R. A.; Ballot, J.; Couvidat, S.; Mathur, S.; Salabert, D.; Silk, J.

    2012-02-10

    We derive new limits on the cold dark matter properties for weakly interacting massive particles (WIMPs), potentially trapped in the solar core by using for the first time the central temperature constrained by boron neutrinos and the central density constrained by the dipolar gravity modes detected with the Global Oscillations at Low Frequency/Solar Helioseismic Observatory instrument. These detections disfavor the presence of non-annihilating WIMPs for masses {<=}10 GeV and spin dependent cross-sections >5 Multiplication-Sign 10{sup -36} cm{sup 2} in the solar core but cannot constrain WIMP annihilation models. We suggest that in the coming years helio- and asteroseismology will provide complementary probes of dark matter.

  20. A Search for Neutrinos from the Solar hep Reaction and the DiffuseSupernova Neutrino Background with the Sudbury Neutrino Observatory

    SciTech Connect

    Aharmim, B.; Ahmed, S.N.; Anthony, A.E.; Beier, E.W.; Bellerive,A.; Bergevin, M.; Biller, S.D.; Boulay, M.G.; Chan, Y.D.; Chen, M.; Chen,X.; Cleveland, B.T.; Cox, G.A.; Currat, C.A.; Dai, X.; Dalnoki-Veress,F.; Deng, H.; Detwiler, J.; DiMarco, M.; Doe, P.J.; Doucas, G.; Drouin,P.-L.; Duncan, F.A.; Dunford, M.; Dunmore, J.A.; Earle, E.D.; Evans,H.C.; Ewan, G.T.; Farine, J.; Fergani, H.; Fleurot, F.; Ford, R.J.; Formaggio, J.A.; Gagnon, N.; Goon, J.T.M.; Graham, K.; Guillian, E.; Hahn, R.L.; Hallin, A.L.; Hallman, E.D.; Harvey, P.J.; Hazama, R.; Heeger, K.M.; Heintzelman, W.J.; Heise, J.; Helmer, R.L.; Hemingway,R.J.; Henning, R.; Hime, A.; Howard, C.; Howe, M.A.; Huang, M.; Jagam,P.; Jelley, N.A.; Klein, J.R.; Kormos, L.L.; Kos, M.; Krueger, A.; Kraus,C.; Krauss, C.B.; Kutter, T.; Kyba, C.C.M.; Labranche, H.; Lange, R.; Law, J.Lawson.I.T.; Lesko, K.T.; Leslie, J.R.; Loach, J.C.; Luoma, S.; MacLellan, R.; Majerus, S.; Mak, H.B.; Maneira, J.; Marino, A.D.; Martin,R.; McCauley, N.; McDonald, A.B.; McGee, S.; Mifflin, C.; Miknaitis,K.K.S.; Miller, M.L.; Monreal, B.; Nickel, B.G.; Noble, A.J.; Norman,E.B.; Oblath, N.S.; Okada, C.E.; O'Keeffe, H.M.; Orebi Gann, G.D.; Oser,S.M.; Ott, R.; Peeters, S.J.M.; Poon, A.W.P.; Prior, G.; Rielage, K.; Robertson, B.C.; Robertson, R.G.H.; Rollin, E.; Schwendener, M.H.; Secrest, J.A.; Seibert, S.R.; Simard, O.; Sims, C.J.; Sinclair, D.; Skensved, P.; Stokstad, R.G.; Stonehill, L.C.; Tesic, G.; Tolich, N.; Tsui, T.; Van Berg, R.; Van de Water, R.G.; VanDevender, B.A.; Virtue,C.J.; Walker, T.J.; Wall, B.L.; Waller, D.; Wan Chan Tseung, H.; Wark,D.L.; Wendland, J.; West, N.; Wilkerson, J.F.; Wilson, J.R.; Wouters,J.M.; Wright, A.; Yeh, M.; Zhang, F.; Zuber, K.

    2006-08-01

    A search has been made for neutrinos from the hep reactionin the Sun and from the diffuse supernova neutrino background (DSNB)using data collected during the first operational phase of the SudburyNeutrino Observatory, with an exposure of 0.65 kilotonne-years. For thehep neutrino search, two events are observed in the effective electronenergy range of 14.3 MeVneutrino oscillations, an upperlimit of 2.3 x 104 cm-2s-1 at the 90 percent confidence level is inferredon the integral total flux of hep neutrinos. For DSNB neutrinos, noevents are observed in the effective electron energy range of 21 MeVneutrino energy range of 22.9 MeVneutrino flux and by two orders of magnitude on theprevious upper limit on the nu e component of the DSNB flux.

  1. Particle Detection in Superfluid Helium: R&D for Low Energy Solar Neutrinos

    SciTech Connect

    Lanou, Robert E., Jr.

    2006-03-31

    This report presents a summary of the results from R&D conducted as a feasibility study in the Department of Physics of Brown University for detection of low energy solar neutrinos utilizing a superfluid helium target. The report outlines the results in several areas: 1) development of experimental facilities, 2) energy deposition by electrons and alphas in superfluid helium, 3) development of wafer and metallic magnetic calorimeters, 4) background studies, 5) coded apertures and conceptual design, 6) Detection of single electrons and 7) a simulation of expected performance of a full scale device. Recommendations for possible future work are also presented. A bibliography of published papers and unpublished doctoral theses is included.

  2. Ground state mass of 81Kr and the solar neutrino problem

    NASA Astrophysics Data System (ADS)

    Kouzes, R. T.; Lowry, M. M.; Bennett, C. L.

    1982-02-01

    The 81Br(3He,t)81Kr, reaction has been used to determine an improved value for the ground state mass of 81Kr. A comparison is made with 51V(3He,t)51Cr and the implications for calibration of the proposed bromine solar neutrino detector are presented. NUCLEAR REACTIONS 81Br(3He,t)81Kr, 51V(3He,t)51Cr, 87Rb(3He,t)87Sr, 85Rb(3He,t)85Sr, E(3He)=24.7 MeV; Q values measured, ground state 81Kr mass inferred.

  3. Neutrino Oscillations and the Sudbury Neutrino Observatory

    NASA Astrophysics Data System (ADS)

    Wark, David

    2001-04-01

    When the existence of the neutrino was almost apologetically first proposed by Wolfgang Pauli it was intended to explain the mysterious apparent absence of energy and momentum in beta decay. 70 years later the neutrino has indeed solved that mystery, but it has generated still more of its own. Are neutrinos massive? Is it possible to create a neutrino with its spin in the same direction as its momentum? What fraction of the mass of the Universe is made up of neutrinos? Are the flavour labels which we put on neutrinos, like electron and muon, really fixed or can they change? Why does no experiment see the predicted flux of neutrinos from the Sun? Why do there appear to be roughly equal numbers of muon and electron neutrinos created in our atmosphere, rather than the 2:1 ratio we would expect? Many of these questions were coupled when Bruno Pontecorvo first suggested that the shortfall in solar neutrino measurements were caused by neutrino oscillations - neutrinos spontaneously changing flavour as they travel from the Sun. 30 years later we still await definitive proof of that conjecture, and providing that proof is the reason for the Sudbury Neutrino Observatory. The talk will discuss the current state of neutrino oscillations studies, and show how the unique capabilities of the Sudbury Neutrino Observatory can provide definitive proof of whether neutrino oscillations are the long-sought answer to the solar neutrino problem.

  4. An Independent Measurement of the Total Active 8B Solar Neutrino Flux Using an Array of 3He Proportional Counters at the Sudbury Neutrino Observatory

    SciTech Connect

    SNO Colla

    2008-06-05

    The Sudbury Neutrino Observatory (SNO) used an array of {sup 3}He proportional counters to measure the rate of neutral-current interactions in heavy water and precisely determined the total active ({nu}{sub x}) {sup 8}B solar neutrino flux. This technique is independent of previous methods employed by SNO. The total flux is found to be 5.54{sub -0.31}{sup +0.33}(stat){sub -0.34}{sup +0.36}(syst) x 10{sup 6} cm{sup -2}s{sup -1}, in agreement with previous measurements and standard solar models. A global analysis of solar and reactor neutrino results yields {Delta}m{sup 2} = 7.94{sub -0.26}{sup +0.42} x 10{sup -5} eV{sup 2} and {theta} = 33.8{sub -1.3}{sup +1.4} degrees. The uncertainty on the mixing angle has been reduced from SNO's previous results.

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

    SciTech Connect

    Aharmim, B.; Ahmad, Q.R.; Ahmed, S.N.; Allen, R.C.; Andersen,T.C.; Anglin, J.D.; Buehler, G.; Barton, J.C.; Beier, E.W.; Bercovitch,M.; Bergevin, M.; Bigu, J.; Biller, S.D.; Black, R.A.; Blevis, I.; Boardman, R.J.; Boger, J.; Bonvin, E.; Boulay, M.G.; Bowler, M.G.; Bowles, T.J.; Brice, S.J.; Browne, M.C.; Bullard, T.V.; Burritt, T.H.; Cameron, J.; Chan, Y.D.; Chen, H.H.; Chen, M.; Chen, X.; Cleveland, B.T.; Cowan, J.H.M.; Cowen, D.F.; Cox, G.A.; Currat, C.A.; Dai, X.; Dalnoki-Veress, F.; Davidson, W.F.; Deng, H.; DiMarco, M.; Doe, P.J.; Doucas, G.; Dragowsky, M.R.; Duba, C.A.; Duncan, F.A.; Dunford, M.; Dunmore, J.A.; Earle, E.D.; Elliott, S.R.; Evans, H.C.; Ewan, G.T.; Farine, J.; Fergani, H.; Ferraris, A.P.; Fleurot, F.; Ford, R.J.; Formaggio, J.A.; Fowler, M.M.; Frame, K.; Frank, E.D.; Frati, W.; Gagnon,N.; Germani, J.V.; Gil, S.; Goldschmidt, A.; Goon, J.T.M.; Graham, K.; Grant, D.R.; Guillian, E.; Hahn, R.L.; Hallin, A.L.; Hallman, E.D.; Hamer, A.S.; Hamian, A.A.; Handler, W.B.; Haq, R.U.; Hargrove, C.K.; Harvey, P.J.; Hazama, R.; Heeger, K.M.; Heintzelman, W.J.; Heise, J.; Helmer, R.L.; Henning, R.; Hepburn, J.D.; Heron, H.; Hewett, J.; Hime,A.; Howard, C.; Howe, M.A.; Huang, M.; Hykawy, J.G.; Isaac, M.C.P.; Jagam, P.; Jamieson, B.; Jelley, N.A.; Jillings, C.; Jonkmans, G.; Kazkaz, K.; Keener, P.T.; Kirch, K.; Klein, J.R.; Knox, A.B.; Komar,R.J.; Kormos, L.L.; Kos, M.; Kouzes, R.; Krueger, A.; Kraus, C.; Krauss,C.B.; Kutter, T.; Kyba, C.C.M.; Labranche, H.; Lange, R.; Law, J.; Lawson, I.T.; Lay, M.; Lee, H.W.; Lesko, K.T.; Leslie, J.R.; Levine, I.; Loach, J.C.; Locke, W.; Luoma, S.; Lyon, J.; MacLellan, R.; Majerus, S.; Mak, H.B.; Maneira, J.; Marino, A.D.; Martin, R.; McCauley, N.; McDonald,A.B.; McDonald, D.S.; McFarlane, K.; McGee, S.; McGregor, G.; MeijerDrees, R.; Mes, H.; Mifflin, C.; Miknaitis, K.K.S.; Miller, M.L.; Milton,G.; Moffat, B.A.; Monreal, B.; Moorhead, M.; Morrissette, B.; Nally,C.W.; Neubauer, M.S.; et al.

    2007-02-01

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

  6. BOUNDS ON LEPTON FLAVOR CHANGING CURRENTS AND THE SOLAR NEUTRINO PUZZLE:. Bounds on Lepton Flavor Changing Currents

    NASA Astrophysics Data System (ADS)

    degl'Innocenti, Scilla; Ricci, Barbara

    We present a phenomenological analysis of a lepton flavor changing current, considering the case of interactions among leptons which change the neutrino flavor and are diagonal in the charged lepton sector. In the case of νe↔νµ transition, we derive a bound on the vector coupling constant GV≤0.16 GF from experimental data on νµ-e scattering. For a transition νe↔νx, from (anti) νe-e scattering experiments and from the analysis of advanced stellar evolutionary phases, we find GV≤0.55 GF. We discuss the compatibility of these data with a possible explanation of the solar neutrino puzzle. We also analyze how the present bounds can be improved in future long baseline neutrino experiments and atmospheric neutrino detectors.

  7. {sup 3}He+{sup 4}He {yields} {sup 7}Be astrophysical S factor

    SciTech Connect

    Brown, T. A. D.; Bordeanu, C.; Snover, K. A.; Storm, D. W.; Melconian, D.; Sallaska, A. L.; Sjue, S. K. L.; Triambak, S.

    2007-11-15

    We present precision measurements of the {sup 3}He+{sup 4}He {yields} {sup 7}Be reaction in the range E{sub c.m.}=0.33 to 1.23 MeV using a small gas cell and detection of both prompt {gamma} rays and {sup 7}Be activity. Our prompt and activity measurements are in good agreement within the experimental uncertainty of several percent. We find S(0)=0.595{+-}0.018 keV b from fits of the Kajino theory to our data. We compare our results with published measurements, and we discuss the consequences for Big Bang Nucleosynthesis and for solar neutrino flux calculations.

  8. Low-energy neutrinos

    NASA Astrophysics Data System (ADS)

    Ludhova, Livia

    2016-05-01

    There exist several kinds of sources emitting neutrinos in the MeV energy range. These low-energy neutrinos from different sources can be often detected by the same multipurpose detectors. The status-of-art of the field of solar neutrinos, geoneutrinos, and the search for sterile neutrino with artificial neutrino sources is provided here; other neutrino sources, as for example reactor or high-energy neutrinos, are described elsewhere. For each of these three fields, the present-day motivation and open questions, as well as the latest experimental results and future perspectives are discussed.

  9. Effects of sudden mixing in the solar core on solar neutrinos and ice ages.

    NASA Technical Reports Server (NTRS)

    Ezer, D.; Cameron, A. G. W.

    1972-01-01

    Some numerical experiments with a solar model have been conducted in connection with the hypothesis regarding the effects of mixing in the solar core. Questions concerning a plausible mechanism by which such a mixing could be produced are explored. The variation of solar luminosity throughout the numerical experiments is shown. In connection with a great change in luminosity after a second mixing, it is suggested that the earth is presently undergoing an ice age.

  10. A GaAs DETECTOR FOR DARK MATTER AND SOLAR NEUTRINO RESEARCH

    SciTech Connect

    T. BOWLES; ET AL

    2000-08-01

    The ability to produce large GaAs crystals with the requisite electronic properties to be fabricated into charged particle and photon detectors would provide a detector medium that would find numerous applications in both applied and fundamental research. Various applications would likely include x-ray detectors on satellites, environmental monitoring, medical imaging, bore hole mining spectroscopy, searches for dark matter, and solar neutrino research. We have carried out the development of GaAs detectors using two commercial crystal growing techniques. We have shown it should be able to grow detectors with 20 cm{sup 2} area and a depletion depth of 1 mm. Detectors of this size would find immediate applications in high-resolution, room temperature, low energy gamma ray measurements. We have also arrived at an understanding of the limitations of the common techniques used to grow GaAs and have determined that it should be possible to produce larger detectors using proprietary methods.

  11. Determination of the νe and total B8 solar neutrino fluxes using the Sudbury Neutrino Observatory Phase I data set

    NASA Astrophysics Data System (ADS)

    Aharmim, B.; Ahmad, Q. R.; Ahmed, S. N.; Allen, R. C.; Andersen, T. C.; Anglin, J. D.; Bühler, G.; Barton, J. C.; Beier, E. W.; Bercovitch, M.; Bergevin, M.; Bigu, J.; Biller, S. D.; Black, R. A.; Blevis, I.; Boardman, R. J.; Boger, J.; Bonvin, E.; Boulay, M. G.; Bowler, M. G.; Bowles, T. J.; Brice, S. J.; Browne, M. C.; Bullard, T. V.; Burritt, T. H.; Cameron, J.; Chan, Y. D.; Chen, H. H.; Chen, M.; Chen, X.; Cleveland, B. T.; Cowan, J. H. M.; Cowen, D. F.; Cox, G. A.; Currat, C. A.; Dai, X.; Dalnoki-Veress, F.; Davidson, W. F.; Deng, H.; Dimarco, M.; Doe, P. J.; Doucas, G.; Dragowsky, M. R.; Duba, C. A.; Duncan, F. A.; Dunford, M.; Dunmore, J. A.; Earle, E. D.; Elliott, S. R.; Evans, H. C.; Ewan, G. T.; Farine, J.; Fergani, H.; Ferraris, A. P.; Fleurot, F.; Ford, R. J.; Formaggio, J. A.; Fowler, M. M.; Frame, K.; Frank, E. D.; Frati, W.; Gagnon, N.; Germani, J. V.; Gil, S.; Goldschmidt, A.; Goon, J. T. M.; Graham, K.; Grant, D. R.; Guillian, E.; Hahn, R. L.; Hallin, A. L.; Hallman, E. D.; Hamer, A. S.; Hamian, A. A.; Handler, W. B.; Haq, R. U.; Hargrove, C. K.; Harvey, P. J.; Hazama, R.; Heeger, K. M.; Heintzelman, W. J.; Heise, J.; Helmer, R. L.; Henning, R.; Hepburn, J. D.; Heron, H.; Hewett, J.; Hime, A.; Howard, C.; Howe, M. A.; Huang, M.; Hykaway, J. G.; Isaac, M. C. P.; Jagam, P.; Jamieson, B.; Jelley, N. A.; Jillings, C.; Jonkmans, G.; Kazkaz, K.; Keener, P. T.; Kirch, K.; Klein, J. R.; Knox, A. B.; Komar, R. J.; Kormos, L. L.; Kos, M.; Kouzes, R.; Krüger, A.; Kraus, C.; Krauss, C. B.; Kutter, T.; Kyba, C. C. M.; Labranche, H.; Lange, R.; Law, J.; Lawson, I. T.; Lay, M.; Lee, H. W.; Lesko, K. T.; Leslie, J. R.; Levine, I.; Loach, J. C.; Locke, W.; Luoma, S.; Lyon, J.; MacLellan, R.; Majerus, S.; Mak, H. B.; Maneira, J.; Marino, A. D.; Martin, R.; McCauley, N.; McDonald, A. B.; McDonald, D. S.; McFarlane, K.; McGee, S.; McGregor, G.; Drees, R. Meijer; Mes, H.; Mifflin, C.; Miknaitis, K. K. S.; Miller, M. L.; Milton, G.; Moffat, B. A.; Monreal, B.; Moorhead, M.; Morrissette, B.; Nally, C. W.; Neubauer, M. S.; Newcomer, F. M.; Ng, H. S.; Nickel, B. G.; Noble, A. J.; Norman, E. B.; Novikov, V. M.; Oblath, N. S.; Okada, C. E.; O'Keeffe, H. M.; Ollerhead, R. W.; Omori, M.; Orrell, J. L.; Oser, S. M.; Ott, R.; Peeters, S. J. M.; Poon, A. W. P.; Prior, G.; Reitzner, S. D.; Rielage, K.; Roberge, A.; Robertson, B. C.; Robertson, R. G. H.; Rosendahl, S. S. E.; Rowley, J. K.; Rusu, V. L.; Saettler, E.; Schülke, A.; Schwendener, M. H.; Secrest, J. A.; Seifert, H.; Shatkay, M.; Simpson, J. J.; Sims, C. J.; Sinclair, D.; Skensved, P.; Smith, A. R.; Smith, M. W. E.; Starinsky, N.; Steiger, T. D.; Stokstad, R. G.; Stonehill, L. C.; Storey, R. S.; Sur, B.; Tafirout, R.; Tagg, N.; Takeuchi, Y.; Tanner, N. W.; Taplin, R. K.; Thorman, M.; Thornewell, P. M.; Tolich, N.; Trent, P. T.; Tserkovnyak, Y. I.; Tsui, T.; Tunnell, C. D.; van Berg, R.; van de Water, R. G.; Virtue, C. J.; Walker, T. J.; Wall, B. L.; Waltham, C. E.; Tseung, H. Wan Chan; Wang, J.-X.; Wark, D. L.; Wendland, J.; West, N.; Wilhelmy, J. B.; Wilkerson, J. F.; Wilson, J. R.; Wittich, P.; Wouters, J. M.; Wright, A.; Yeh, M.; Zuber, K.

    2007-04-01

    This article provides the complete description of results from the Phase I data set of the Sudbury Neutrino Observatory (SNO). The Phase I data set is based on a 0.65 kiloton-year exposure of 2H2O (in the following denoted as D2O) to the solar B8 neutrino flux. Included here are details of the SNO physics and detector model, evaluations of systematic uncertainties, and estimates of backgrounds. Also discussed are SNO's approach to statistical extraction of the signals from the three neutrino reactions (charged current, neutral current, and elastic scattering) and the results of a search for a day-night asymmetry in the νe flux. Under the assumption that the B8 spectrum is undistorted, the measurements from this phase yield a solar νe flux of ϕ(νe)=1.76-0.05+0.05(stat.)-0.09+0.09(syst.)×106 cm-2 s-1 and a non-νe component of ϕ(νμτ)=3.41-0.45+0.45(stat.)-0.45+0.48(syst.)×106 cm-2 s-1. The sum of these components provides a total flux in excellent agreement with the predictions of standard solar models. The day-night asymmetry in the νe flux is found to be Ae=7.0±4.9(stat.)-1.2+1.3%(syst.), when the asymmetry in the total flux is constrained to be zero.

  12. Earth regeneration of solar neutrinos at SNO and Super-Kamiokande

    SciTech Connect

    Barger, V.; Marfatia, D.; Whisnant, K.; Wood, B. P.

    2001-10-01

    We analyze the 1258-day Super-Kamiokande day and night solar neutrino energy spectra with various {chi}{sup 2} definitions. The best-fit lies in the large mixing angle (LMA) region at ({Delta}m{sup 2},tan{sup 2}{theta})=(5.01 x 10{sup -5} eV{sup 2},0.60), independently of whether systematic errors are included in the {chi}{sup 2} definition. We compare the exclusion and allowed regions from the different definitions and choose the most suitable definition to predict the regions from SNO at the end of three years of data accumulation. We first work under the assumption that Super-Kamiokande ''sees'' a flux-suppressed flat energy spectrum. Then, we consider the possibility of each one of the three Mikheyev-Smirnov-Wolfenstein regions being the solution to the solar neutrino problem. We find that the exclusion and allowed regions for the flat spectrum hypothesis and the LMA and low probability, low mass solutions are alike. In three years, we expect SNO to find very similar regions to that obtained by Super-Kamiokande. We evaluate whether the zenith angle distribution at SNO with optimum binning will add anything to the analysis of the day and night spectra; for comparison, we show the results of our analysis of the 1258-day zenith angle distribution from Super-Kamiokande, for which the best-fit parameters are ({Delta}m{sup 2},tan{sup 2}{theta})=(5.01 x 10{sup -5} eV{sup 2},0.56).

  13. Sterile neutrinos

    NASA Astrophysics Data System (ADS)

    Kopp, J.; Machado, P. A. N.; Maltoni, M.; Schwetz, T.

    2016-06-01

    We characterize statistically the indications of a presence of one or more light sterile neutrinos from MiniBooNE and LSND data, together with the reactor and gallium anomalies, in the global context. The compatibility of the aforementioned signals with null results from solar, atmospheric, reactor, and accelerator experiments is evaluated. We conclude that a severe tension is present in the global fit, and therefore the addition of eV-scale sterile neutrinos does not satisfactorily explain the anomalies.

  14. Astrophysical S factor for the 4He(3He,γ)7Be reaction at medium energies

    NASA Astrophysics Data System (ADS)

    Carmona-Gallardo, M.; Nara Singh, B. S.; Tengblad, O.; Hass, M.; Alcorta, M.; Borge, M. J. G.; Briz, J. A.; Cruz, C.; Cubero, M.; Domínguez-Reyes, R.; Fulton, B. R.; Fynbo, H.; Gordillo, N.; Haquin, G.; Nir-El, Y.; Kumar, V.; Maira, A.; McGrath, J.; Muñoz-Martín, A.; Perea, A.; Yungreis, Z.

    2012-02-01

    The astrophysical S factor for the 4He(3He,γ)7Be direct capture reaction plays a major role in the context of solar neutrino flux and primordial 7Li abundances that demand accurate information on the reaction. We report here our recent cross section measurements using the activation method in the region of ECM = 900-2800 keV, that aim to shed light on the discrepancies in the existing data and lead to a more accurate extrapolation of the S factor.

  15. 7Be(p,gamma)8B S-factor from Ab Initio Wave Functions

    SciTech Connect

    Navratil, P; Bertulani, C A; Caurier, E

    2006-10-12

    There has been a significant progress in ab initio approaches to the structure of light nuclei. Starting from realistic two- and three-nucleon interactions the ab initio no-core shell model (NCSM) predicts low-lying levels in p-shell nuclei. It is a challenging task to extend ab initio methods to describe nuclear reactions. We present here a brief overview of the first steps taken toward nuclear reaction applications. In particular, we discuss our calculation of the {sup 7}Be(p,{gamma}){sup 8}B S-factor. We also present our first results of the {sup 3}He({alpha},{gamma}){sup 7}Be S-factor and of the S-factor of the mirror reaction {sup 3}H({alpha},{gamma}){sup 7}Li. The {sup 7}Be(p,{gamma}){sup 8}B and {sup 3}He({alpha},{gamma}){sup 7}Be reactions correspond to the most important uncertainties in solar model predictions of neutrino fluxes.

  16. Neutrino Observations from the Sudbury Neutrino Observatory

    DOE R&D Accomplishments Database

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

    2001-09-24

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

  17. New measurement of the 3He(α,γ)7Be cross section at medium energies

    NASA Astrophysics Data System (ADS)

    Carmona-Gallardo, M.; Nara Singh, B. S.; Borge, M. J. G.; Briz, J. A.; Cubero, M.; Fulton, B. R.; Fynbo, H.; Gordillo, N.; Hass, M.; Haquin, G.; Maira, A.; Nácher, E.; Nir-El, Y.; Kumar, V.; McGrath, J.; Muñoz-Martín, A.; Perea, A.; Pesudo, V.; Ribeiro, G.; Sánchez del Rio, J.; Tengblad, O.; Yaniv, R.; Yungreis, Z.

    2012-09-01

    We report on a new cross-section measurement for the 3He(α, γ)7Be reaction at three medium energies of Ec.m. between 1 and 3 MeV. The interest stems from the significant role played by the reaction in calculating an accurate solar neutrino flux and the primordial 7Li abundance. The energy dependence of the astrophysical S34 factor observed in the present work, especially above 1 MeV, highlights the need to constrain theories in order to obtain a precise extrapolated value for S34(0). In this context, a comparison with the recent theoretical work in a fully microscopic fermionic molecular dynamics approach and a few other representative calculations emphasize the need for further experimental as well as theoretical work to resolve the existing conflicts.

  18. Neutrino oscillation studies with reactors.

    PubMed

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

    2015-01-01

    Nuclear reactors are one of the most intense, pure, controllable, cost-effective and well-understood sources of neutrinos. Reactors have played a major role in the study of neutrino oscillations, a phenomenon that indicates that neutrinos have mass and that neutrino flavours are quantum mechanical mixtures. Over the past several decades, reactors were used in the discovery of neutrinos, were crucial in solving the solar neutrino puzzle, and allowed the determination of the smallest mixing angle θ13. In the near future, reactors will help to determine the neutrino mass hierarchy and to solve the puzzling issue of sterile neutrinos. PMID:25913819

  19. Neutrino oscillation studies with reactors.

    PubMed

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

    2015-04-27

    Nuclear reactors are one of the most intense, pure, controllable, cost-effective and well-understood sources of neutrinos. Reactors have played a major role in the study of neutrino oscillations, a phenomenon that indicates that neutrinos have mass and that neutrino flavours are quantum mechanical mixtures. Over the past several decades, reactors were used in the discovery of neutrinos, were crucial in solving the solar neutrino puzzle, and allowed the determination of the smallest mixing angle θ13. In the near future, reactors will help to determine the neutrino mass hierarchy and to solve the puzzling issue of sterile neutrinos.

  20. Neutrino oscillation studies with reactors

    SciTech Connect

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

    2015-04-27

    Nuclear reactors are one of the most intense, pure, controllable, cost-effective and well-understood sources of neutrinos. Reactors have played a major role in the study of neutrino oscillations, a phenomenon that indicates that neutrinos have mass and that neutrino flavours are quantum mechanical mixtures. Over the past several decades, reactors were used in the discovery of neutrinos, were crucial in solving the solar neutrino puzzle, and allowed the determination of the smallest mixing angle θ13. In the near future, reactors will help to determine the neutrino mass hierarchy and to solve the puzzling issue of sterile neutrinos.

  1. Neutrino oscillation studies with reactors

    DOE PAGES

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

    2015-04-27

    Nuclear reactors are one of the most intense, pure, controllable, cost-effective and well-understood sources of neutrinos. Reactors have played a major role in the study of neutrino oscillations, a phenomenon that indicates that neutrinos have mass and that neutrino flavours are quantum mechanical mixtures. Over the past several decades, reactors were used in the discovery of neutrinos, were crucial in solving the solar neutrino puzzle, and allowed the determination of the smallest mixing angle θ13. In the near future, reactors will help to determine the neutrino mass hierarchy and to solve the puzzling issue of sterile neutrinos.

  2. Novel Ideas for Neutrino Beams

    SciTech Connect

    Peach, Ken

    2007-04-23

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

  3. Neutrino oscillation studies with reactors

    PubMed Central

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

    2015-01-01

    Nuclear reactors are one of the most intense, pure, controllable, cost-effective and well-understood sources of neutrinos. Reactors have played a major role in the study of neutrino oscillations, a phenomenon that indicates that neutrinos have mass and that neutrino flavours are quantum mechanical mixtures. Over the past several decades, reactors were used in the discovery of neutrinos, were crucial in solving the solar neutrino puzzle, and allowed the determination of the smallest mixing angle θ13. In the near future, reactors will help to determine the neutrino mass hierarchy and to solve the puzzling issue of sterile neutrinos. PMID:25913819

  4. Neutrino measurements from the Sun and Earth: Results from Borexino

    SciTech Connect

    Bellini, G.; Caccianiga, B.; D’Angelo, D.; Giammarchi, M.; Lombardi, P.; Ludhova, L.; Meroni, E.; Miramonti, L.; Ranucci, G. Re, A.; Benziger, J.; Bick, D.; Hagner, C.; Meyer, M.; Bonfini, G.; Cavalcante, P.; Gabriele, F.; Gazzana, S.; Ianni, Aldo; Laubenstein, M.; and others

    2015-07-15

    Important neutrino results came recently from Borexino, a massive, calorimetric liquid scintillator detector installed at the underground Gran Sasso Laboratory. With its unprecedented radiopurity levels achieved in the core of the detection medium, it is the only experiment in operation able to study in real time solar neutrino interactions in the challenging sub-MeV energy region. The recently achieved breakthrough observation of the fundamental pp flux, the precise measurement of the {sup 7}Be solar neutrino flux, and the results concerning the pep, {sup 8}B and CNO fluxes, together with their physics implications, are described in this work. Moreover, the detector has also provided a clean detection of terrestrial neutrinos, from which they emerge as a new probe of the interior of the Earth.

  5. Enrichment services for chromium isotopes for the GALLEX (gallium experiment) international collaboration experiment on solar neutrino flux

    NASA Astrophysics Data System (ADS)

    Szady, Andrew J.

    1990-07-01

    Detailed discussions were held with members of the Gallium Experiment (GALLEX) international solar neutrino research collaboration concerning negotiations to provide $1.4 million in services to enrich (50)Cr for a (51)Cr neutrino source. The source will be used to calibrate the 20-ton gallium solar neutrino detector currently in place in the Gran Sasso Laboratory in Italy. Funding approval for the enrichment services is expected from the European Common Market by October 19, 1990. The discussions focused on the technical aspects of the enrichment, the health and safety requirements for handling the process gas, cost projections, schedule, the Work-for-Others contract, and the method of payment. Discussions were also held with members of the Nuclear Physics Dept. at the University of Milan concerning the availability of isotopes enriched by the Calutron at the Oak Ridge National Laboratory. Very high purity material is needed to grow crystals for use in double beta decay detectors. Finally, working sessions were held to draft a coauthored paper on the results of using the gas centrifuge to remove trace quantities of (85)Kr from natural xenon.

  6. Global analyses of neutrino oscillation experiments

    NASA Astrophysics Data System (ADS)

    Gonzalez-Garcia, M. C.; Maltoni, Michele; Schwetz, Thomas

    2016-07-01

    We summarize the determination of some neutrino properties from the global analysis of solar, atmospheric, reactor, and accelerator neutrino data in the framework of three-neutrino mixing as well as in some extended scenarios such as the mixing with eV-scale sterile neutrinos invoked for the interpretation of the short baseline anomalies, and the presence of non-standard neutrino interactions.

  7. Measurement of the solar neutrino capture rate with gallium metal. III. Results for the 2002-2007 data-taking period

    SciTech Connect

    Abdurashitov, J. N.; Gavrin, V. N.; Gorbachev, V. V.; Gurkina, P. P.; Ibragimova, T. V.; Kalikhov, A. V.; Khairnasov, N. G.; Knodel, T. V.; Mirmov, I. N.; Shikhin, A. A.; Veretenkin, E. P.; Yants, V. E.; Zatsepin, G. T.; Bowles, T. J.; Elliott, S. R.; Teasdale, W. A.; Nico, J. S.; Cleveland, B. T.; Wilkerson, J. F.

    2009-07-15

    The Russian-American experiment SAGE began to measure the solar neutrino capture rate with a target of gallium metal in December 1989. Measurements have continued with only a few brief interruptions since that time. In this article we present the experimental improvements in SAGE since its last published data summary in December 2001. Assuming the solar neutrino production rate was constant during the period of data collection, combined analysis of 168 extractions through December 2007 gives a capture rate of solar neutrinos with energy more than 233 keV of 65.4{sub -3.0}{sup +3.1} (stat) {sub -2.8}{sup +2.6} (syst) SNU. The weighted average of the results of all three Ga solar neutrino experiments, SAGE, Gallex, and GNO, is now 66.1{+-}3.1 SNU, where statistical and systematic uncertainties have been combined in quadrature. During the recent period of data collection a new test of SAGE was made with a reactor-produced {sup 37}Ar neutrino source. The ratio of observed to calculated rates in this experiment, combined with the measured rates in the three prior {sup 51}Cr neutrino-source experiments with Ga, is 0.87{+-}0.05. A probable explanation for this low result is that the cross section for neutrino capture by the two lowest-lying excited states in {sup 71}Ge has been overestimated. If we assume these cross sections are zero, then the standard solar model including neutrino oscillations predicts a total capture rate in Ga in the range of 63 SNU to 66 SNU with an uncertainty of about 4%, in good agreement with experiment. We derive the current value of the neutrino flux produced in the Sun by the proton-proton fusion reaction to be {phi}{sub pp}{sup {center_dot}}=(6.0{+-}0.8)x10{sup 10}/(cm{sup 2} s), which agrees well with the pp flux predicted by the standard solar model. Finally, we make several tests and show that the data are consistent with the assumption that the solar neutrino production rate is constant in time.

  8. Design Considerations for a Large Metal-Loaded Liquid Scintillator Detector with Applications for Solar Neutrino and Double Beta Decay Studies

    NASA Astrophysics Data System (ADS)

    Doe, Peter; Robertson, Hamish; Gehman, Victor; Gehring, George; Iwamoto, Hideko; Will, Doug

    2002-10-01

    The realization of a large, metal-loaded liquid scintillator detector has exciting possibilities in the areas of Double Beta Decay, low-energy solar neutrino, and supernova neutrino studies. We have used statistical considerations to arrive at an analytical expression which will allow us to optimize a detector design for energy and spatial resolution. Using these results, we consider the possible use of Avalanche Photo-Diode detectors operated in the Geiger regime as a possible replacement for Photomultiplier Tubes.

  9. Measurements of the atmospheric neutrino flux by Super-Kamiokande: Energy spectra, geomagnetic effects, and solar modulation

    NASA Astrophysics Data System (ADS)

    Richard, E.; Okumura, K.; Abe, K.; Haga, Y.; Hayato, Y.; Ikeda, M.; Iyogi, K.; Kameda, J.; Kishimoto, Y.; Miura, M.; Moriyama, S.; Nakahata, M.; Nakajima, T.; Nakano, Y.; Nakayama, S.; Orii, A.; Sekiya, H.; Shiozawa, M.; Takeda, A.; Tanaka, H.; Tomura, T.; Wendell, R. A.; Akutsu, R.; Irvine, T.; Kajita, T.; Kaneyuki, K.; Nishimura, Y.; Labarga, L.; Fernandez, P.; Gustafson, J.; Kachulis, C.; Kearns, E.; Raaf, J. L.; Stone, J. L.; Sulak, L. R.; Berkman, S.; Nantais, C. M.; Tanaka, H. A.; Tobayama, S.; Goldhaber, M.; Kropp, W. R.; Mine, S.; Weatherly, P.; Smy, M. B.; Sobel, H. W.; Takhistov, V.; Ganezer, K. S.; Hartfiel, B. L.; Hill, J.; Hong, N.; Kim, J. Y.; Lim, I. T.; Park, R. G.; Himmel, A.; Li, Z.; O'Sullivan, E.; Scholberg, K.; Walter, C. W.; Wongjirad, T.; Ishizuka, T.; Tasaka, S.; Jang, J. S.; Learned, J. G.; Matsuno, S.; Smith, S. N.; Friend, M.; Hasegawa, T.; Ishida, T.; Ishii, T.; Kobayashi, T.; Nakadaira, T.; Nakamura, K.; Oyama, Y.; Sakashita, K.; Sekiguchi, T.; Tsukamoto, T.; Suzuki, A. T.; Takeuchi, Y.; Yano, T.; Cao, S. V.; Hiraki, T.; Hirota, S.; Huang, K.; Kikawa, T.; Minamino, A.; Nakaya, T.; Suzuki, K.; Fukuda, Y.; Choi, K.; Itow, Y.; Suzuki, T.; Mijakowski, P.; Frankiewicz, K.; Hignight, J.; Imber, J.; Jung, C. K.; Li, X.; Palomino, J. L.; Wilking, M. J.; Yanagisawa, C.; Fukuda, D.; Ishino, H.; Kayano, T.; Kibayashi, A.; Koshio, Y.; Mori, T.; Sakuda, M.; Xu, C.; Kuno, Y.; Tacik, R.; Kim, S. B.; Okazawa, H.; Choi, Y.; Nishijima, K.; Koshiba, M.; Totsuka, Y.; Suda, Y.; Yokoyama, M.; Bronner, C.; Hartz, M.; Martens, K.; Marti, Ll.; Suzuki, Y.; Vagins, M. R.; Martin, J. F.; Konaka, A.; Chen, S.; Zhang, Y.; Wilkes, R. J.; Super-Kamiokande Collaboration

    2016-09-01

    A comprehensive study of the atmospheric neutrino flux in the energy region from sub-GeV up to several TeV using the Super-Kamiokande (SK) water Cherenkov detector is presented in this paper. The energy and azimuthal spectra, and variation over time, of the atmospheric νe+ν¯ e and νμ+ν¯μ fluxes are measured. The energy spectra are obtained using an iterative unfolding method by combining various event topologies with differing energy responses. The azimuthal spectra depending on energy and zenith angle, and their modulation by geomagnetic effects, are also studied. A predicted east-west asymmetry is observed in both the νe and νμ samples at 8.0 σ and 6.0 σ significance, respectively, and an indication that the asymmetry dipole angle changes depending on the zenith angle was seen at the 2.2 σ level. The measured energy and azimuthal spectra are consistent with the current flux models within the estimated systematic uncertainties. A study of the long-term correlation between the atmospheric neutrino flux and the solar magnetic activity cycle is performed, and a weak preference for a correlation was seen at the 1.1 σ level, using SK-I-SK-IV data spanning a 20-year period. For several particularly strong solar activity periods, corresponding to Forbush decrease events, no theoretical prediction is available but a deviation below the typical neutrino event rate is seen at the 2.4 σ level. The seasonal modulation of the neutrino flux is also examined, but the change in flux at the SK site is predicted to be negligible, and, as expected, no evidence for a seasonal correlation is seen.

  10. The Sudbury Neutrino Observatory

    NASA Astrophysics Data System (ADS)

    Bellerive, A.; Klein, J. R.; McDonald, A. B.; Noble, A. J.; Poon, A. W. P.

    2016-07-01

    This review paper provides a summary of the published results of the Sudbury Neutrino Observatory (SNO) experiment that was carried out by an international scientific collaboration with data collected during the period from 1999 to 2006. By using heavy water as a detection medium, the SNO experiment demonstrated clearly that solar electron neutrinos from 8B decay in the solar core change into other active neutrino flavors in transit to Earth. The reaction on deuterium that has equal sensitivity to all active neutrino flavors also provides a very accurate measure of the initial solar flux for comparison with solar models. This review summarizes the results from three phases of solar neutrino detection as well as other physics results obtained from analyses of the SNO data.

  11. Nucleosynthesis and Neutrinos

    SciTech Connect

    Kajino, Toshitaka

    2011-05-06

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

  12. Neutrino physics with multi-ton scale liquid xenon detectors

    SciTech Connect

    Baudis, L.; Ferella, A.; Kish, A.; Manalaysay, A.; Undagoitia, T. Marrodán; Schumann, M. E-mail: alfredo.ferella@lngs.infn.it E-mail: aaronm@ucdavis.edu E-mail: marc.schumann@lhep.unibe.ch

    2014-01-01

    We study the sensitivity of large-scale xenon detectors to low-energy solar neutrinos, to coherent neutrino-nucleus scattering and to neutrinoless double beta decay. As a concrete example, we consider the xenon part of the proposed DARWIN (Dark Matter WIMP Search with Noble Liquids) experiment. We perform detailed Monte Carlo simulations of the expected backgrounds, considering realistic energy resolutions and thresholds in the detector. In a low-energy window of 2–30 keV, where the sensitivity to solar pp and {sup 7}Be-neutrinos is highest, an integrated pp-neutrino rate of 5900 events can be reached in a fiducial mass of 14 tons of natural xenon, after 5 years of data. The pp-neutrino flux could thus be measured with a statistical uncertainty around 1%, reaching the precision of solar model predictions. These low-energy solar neutrinos will be the limiting background to the dark matter search channel for WIMP-nucleon cross sections below ∼ 2 × 10{sup −48} cm{sup 2} and WIMP masses around 50 GeV⋅c{sup −2}, for an assumed 99.5% rejection of electronic recoils due to elastic neutrino-electron scatters. Nuclear recoils from coherent scattering of solar neutrinos will limit the sensitivity to WIMP masses below ∼ 6 GeV⋅c{sup −2} to cross sections above ∼ 4 × 10{sup −45}cm{sup 2}. DARWIN could reach a competitive half-life sensitivity of 5.6 × 10{sup 26} y to the neutrinoless double beta decay of {sup 136}Xe after 5 years of data, using 6 tons of natural xenon in the central detector region.

  13. Core-collapse Supernovae from 9 to 120 Solar Masses Based on Neutrino-powered Explosions

    NASA Astrophysics Data System (ADS)

    Sukhbold, Tuguldur; Ertl, T.; Woosley, S. E.; Brown, Justin M.; Janka, H.-T.

    2016-04-01

    Nucleosynthesis, light curves, explosion energies, and remnant masses are calculated for a grid of supernovae (SNe) resulting from massive stars with solar metallicity and masses from 9.0 to 120 {M}⊙ . The full evolution is followed using an adaptive reaction network of up to 2000 nuclei. A novel aspect of the survey is the use of a one-dimensional neutrino transport model for the explosion. This explosion model has been calibrated to give the observed energy for SN 1987A, using five standard progenitors, and for the Crab SN using a 9.6 {M}⊙ progenitor. As a result of using a calibrated central engine, the final kinetic energy of the SN is variable and sensitive to the structure of each pre-SN star. Many progenitors with extended core structures do not explode, but become black holes (BHs), and the masses of exploding stars do not form a simply connected set. The resulting nucleosynthesis agrees reasonably well with the Sun provided that a reasonable contribution from SNe Ia is also allowed, but with a deficiency of light s-process isotopes. The resulting neutron star initial mass function has a mean gravitational mass near 1.4 {M}⊙ . The average BH mass is about 9 {M}⊙ if only the helium core implodes, and 14 {M}⊙ if the entire pre-SN star collapses. Only ˜10% of SNe come from stars over 20 {M}⊙ , and some of these are Type Ib or Ic. Some useful systematics of Type IIp light curves are explored.

  14. Solar r-process-constrained actinide production in neutrino-driven winds of supernovae

    NASA Astrophysics Data System (ADS)

    Goriely, S.; Janka, H.-Th.

    2016-07-01

    Long-lived radioactive nuclei play an important role as nucleo-cosmochronometers and as cosmic tracers of nucleosynthetic source activity. In particular, nuclei in the actinide region like thorium, uranium, and plutonium can testify to the enrichment of an environment by the still enigmatic astrophysical sources that are responsible for the production of neutron-rich nuclei by the rapid neutron-capture process (r-process). Supernovae and merging neutron-star (NS) or NS-black hole binaries are considered as most likely sources of the r-nuclei. But arguments in favour of one or the other or both are indirect and make use of assumptions; they are based on theoretical models with remaining simplifications and shortcomings. An unambiguous observational determination of a production event is still missing. In order to facilitate searches in this direction, e.g. by looking for radioactive tracers in stellar envelopes, the interstellar medium or terrestrial reservoirs, we provide improved theoretical estimates and corresponding uncertainty ranges for the actinide production (232Th, 235, 236, 238U, 237Np, 244Pu, and 247Cm) in neutrino-driven winds of core-collapse supernovae. Since state-of-the-art supernova models do not yield r-process viable conditions - but still lack, for example, the effects of strong magnetic fields - we base our investigation on a simple analytical, Newtonian, adiabatic and steady-state wind model and consider the superposition of a large number of contributing components, whose nucleosynthesis-relevant parameters (mass weight, entropy, expansion time-scale, and neutron excess) are constrained by the assumption that the integrated wind nucleosynthesis closely reproduces the Solar system distribution of r-process elements. We also test the influence of uncertain nuclear physics.

  15. Searching for resonances in the unbound 6Be nucleus using a radioactive 7Be beam

    SciTech Connect

    Chae, K. Y.; Bardayan, Daniel W; Blackmon, Jeffery C; Smith, Michael Scott; Champagne, A. E.; Fitzgerald, R. P.; Visser, D. W.; Das, Jiban; Guimaraes, V.; Jones, K. L.; Pain, S. D.; Thomas, J. S.; Johnson, M. S.; KOZUB, RAYMOND L; Livesay, R. J.; Ma, Z.; Nesaraja, Caroline D

    2012-01-01

    Knowledge of the 3He(3He,2p)4He reaction is important for understanding stellar burning and solar neutrino production. Previous measurements have found a surprisingly large rise in the cross section at low energies that could be due to a low energy resonance in the 3He + 3He (6Be) system or electron screening. In the 6Be nucleus, however, no excited states have been observed above the first 2+ state at Ex = 1:67 MeV up to 23 MeV, even though several are expected. The d(7Be,t)6Be reaction has been studied for the first time to search for resonances in the 6Be nucleus that may affect our understanding of the 3He(3He,2p)4He reaction. A 100-MeV radioactive 7Be beam from the Holifield Radioactive Ion Beam Facility (HRIBF) was used to bombard CD2 targets, and tritons were detected by the Silicon Detector Array (SIDAR). It appears that a combination of reaction mechanisms are necessary to explain the observed triton energy spectrum.

  16. Los Alamos Science, Number 25 -- 1997: Celebrating the neutrino

    SciTech Connect

    Cooper, N.G.

    1997-12-31

    This issue is devoted to the neutrino and its remaining mysteries. It is divided into the following areas: (1) The Reines-Cowan experiment -- detecting the poltergeist; (2) The oscillating neutrino -- an introduction to neutrino masses and mixing; (3) A brief history of neutrino experiments at LAMPF; (4) A thousand eyes -- the story of LSND (Los Alamos neutrino oscillation experiment); (5) The evidence for oscillations; (6) The nature of neutrinos in muon decay and physics beyond the Standard Model; (7) Exorcising ghosts -- in pursuit of the missing solar neutrinos; (8) MSW -- a possible solution to the solar neutrino problem; (8) Neutrinos and supernovae; and (9) Dark matter and massive neutrinos.

  17. Be7 solar neutrino measurement with KamLAND

    SciTech Connect

    Gando, A.; Gando, Y.; Hanakago, H.; Ikeda, H.; Inoue, K.; Ishidoshiro, K.; Ishikawa, H.; Kishimoto, Y.; Koga, M.; Matsuda, R.; Matsuda, S.; Mitsui, T.; Motoki, D.; Nakajima, K.; Nakamura, K.; Obata, A.; Oki, A.; Oki, Y.; Otani, M.; Shimizu, I.; Shirai, J.; Suzuki, A.; Tamae, K.; Ueshima, K.; Watanabe, H.; Xu, B. D.; Yamada, S.; Yamauchi, Y.; Yoshida, H.; Kozlov, A.; Takemoto, Y.; Yoshida, S.; Grant, C.; Keefer, G.; McKee, D. W.; Piepke, A.; Banks, T. I.; Bloxham, T.; Freedman, S. J.; Fujikawa, B. K.; Han, K.; Hsu, L.; Ichimura, K.; Murayama, H.; O'Donnell, T.; Steiner, H. M.; Winslow, L. A.; Dwyer, D.; Mauger, C.; McKeown, R. D.; Zhang, C.; Berger, B. E.; Lane, C. E.; Maricic, J.; Miletic, T.; Learned, J. G.; Sakai, M.; Horton-Smith, G. A.; Tang, A.; Downum, K. E.; Tolich, K.; Efremenko, Y.; Kamyshkov, Y.; Perevozchikov, O.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Detwiler, J. A.; Enomoto, S.; Heeger, K.; Decowski, M. P.

    2015-11-30

    We report a measurement of the neutrino-electron elastic scattering rate of 862 keV 7Be solar neutrinos based on a 165.4 kt d exposure of KamLAND. The observed rate is 582±94(kt d)₋1, which corresponds to an 862-keV 7Be solar neutrino flux of (3.26±0.52)×109cm₋2s₋1, assuming a pure electron-flavor flux. Comparing this flux with the standard solar model prediction and further assuming three-flavor mixing, a νe survival probability of 0.66±0.15 is determined from the KamLAND data. Lastly, utilizing a global three-flavor oscillation analysis, we obtain a total 7Be solar neutrino flux of (5.82±1.02)×109cm₋2s₋1, which is consistent with the standard solar model predictions.

  18. Neutrinos beyond the Standard Model

    SciTech Connect

    Valle, J.W.F.

    1989-08-01

    I review some basic aspects of neutrino physics beyond the Standard Model such as neutrino mixing and neutrino non-orthogonality, universality and CP violation in the lepton sector, total lepton number and lepton flavor violation, etc.. These may lead to neutrino decays and oscillations, exotic weak decay processes, neutrinoless double /beta/ decay, etc.. Particle physics models are discussed where some of these processes can be sizable even in the absence of measurable neutrino masses. These may also substantially affect the propagation properties of solar and astrophysical neutrinos. 39 refs., 4 figs.

  19. Results from Neutrino Oscillations Experiments

    SciTech Connect

    Aguilar-Arevalo, Alexis

    2010-09-10

    The interpretation of the results of early solar and atmospheric neutrino experiments in terms of neutrino oscillations has been verified by several recent experiments using both, natural and man-made sources. The observations provide compelling evidence in favor of the existence of neutrino masses and mixings. These proceedings give a general description of the results from neutrino oscillation experiments, the current status of the field, and some possible future developments.

  20. Bolometric detection of neutrinos

    NASA Technical Reports Server (NTRS)

    Cabrera, B.; Krauss, L. M.; Wilczek, F.

    1985-01-01

    Elastic neutrino scattering off electrons in crystalline silicon at 1-10 mK results in measurable temperature changes in macroscopic amounts of material, even for low-energy (less than 0.41-MeV) pp neutrinos from the sun. New detectors for bolometric measurement of low-energy neutrino interactions, including coherent nuclear elastic scattering, are proposed. A new and more sensitive search for oscillations of reactor antineutrinos is practical (about 100 kg of Si), and would lay the groundwork for a more ambitious measurement of the spectrum of pp, Be-7, and B-8 solar neutrinos, and of supernovae anywhere in the Galaxy (about 10 tons of Si).

  1. Radiative capture estimates via analytic continuation of elastic-scattering data, and the solar-neutrino problem

    NASA Astrophysics Data System (ADS)

    Iwinski, Z. R.; Rosenberg, Leonard; Spruch, Larry

    1984-01-01

    Measurements of σγ for 3He(α,γ)7Be, central to the solar ν problem, disagree. In a direct capture model, the normalization constants N32 and N12 of the P32 and P12 bound state wave functions of 7Be at large 3He-α separations determine σγ. N32 and N12 are given by (simpler) measurements of σγ at a higher energy E, or, as here, by analytic continuation of the 3He-α p32 and p12 phase shifts, δ(E). The method has been successfully tested on calculations of Tang et al. Better measurements of δ(E) are called for. [NUCLEAR REACTIONS 3He(α,γ)7Be, E<300 keV, 3He(α,α)3He, E<4 MeV, effective range function, analytic continuation technique, bound state energies, and normalization.

  2. Neutrino propagation in a fluctuating sun

    SciTech Connect

    Burgess, C.P.; Michaud, D.

    1997-05-01

    We adapt to neutrino physics a general formulation for particle propagation in fluctuating media, initially developed for applications to electromagnetism and neutron optics. In leading approximation this formalism leads to the usual MSW effective Hamiltonian governing neutrino propagation through a medium. Next-to-leading contributions describe deviations from this description, which arise due to neutrino interactions with fluctuations in the medium. We compute these corrections for two types of fluctuations: (i) microscopic thermal fluctuations and (ii) macroscopic fluctuations in the medium{close_quote}s density. While the first of these reproduces standard estimates, which are negligible for applications to solar neutrinos, we find that the second can be quite large, since it grows in size with the correlation length of the fluctuation. We consider two models in some detail. For fluctuations whose correlations extend only over a local region in space of length l, appreciable effects for MSW oscillations arise if ({delta}n/n){sup 2}l{approx_gt}100m or so. Alternatively, a crude model of helioseismic p-waves gives appreciable effects only when ({delta}n/n){approx_gt}1{percent}. In general the dominant effect is to diminish the quality of the resonance, making the suppression of the {sup 7}Be neutrinos a good experimental probe of fluctuations deep within the sun. Fluctuations can also provide a new mechanism for reducing the solar neutrino flux, giving an energy-independent suppression factor of 1/2 away from the resonant region, even for small vacuum mixing angles. {copyright} 1997 Academic Press, Inc.

  3. Why is the neutrino oscillation formula expanded in Δ m {21/2}/Δ m {31/2} still accurate near the solar resonance in matter?

    NASA Astrophysics Data System (ADS)

    Xu, Xun-Jie

    2015-10-01

    The conventional approximate formula for neutrino oscillation in matter which is obtained from the expansion in terms of the ratio of mass square differences α = Δ m 21 2 /Δ m 31 2 ≈ 0.03, first proposed by Cervera, et al. and Freund, turns out to be an accurate formula for accelerator neutrino experiments. Originally it required the neutrino energy to be well above the solar resonance to validate the expansion but it is found to be still very accurate when the formula is extrapolated to the resonance, which is practically important for the T2K experiment. This paper shows that the accuracy is guaranteed by cancellations of branch cut singularities and also, for the first time, analytically computes the actual error of the formula. The actual error implies that the original requirement can be safely removed in current experiments.

  4. Sudbury Neutrino Observatory

    SciTech Connect

    Beier, E.W.

    1992-03-01

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

  5. A search for astrophysical burst signals at the Sudbury Neutrino Observatory

    NASA Astrophysics Data System (ADS)

    Aharmim, B.; Ahmed, S. N.; Anthony, A. E.; Barros, N.; Beier, E. W.; Bellerive, A.; Beltran, B.; Bergevin, M.; Biller, S. D.; Boudjemline, K.; Boulay, M. G.; Cai, B.; Chan, Y. D.; Chauhan, D.; Chen, M.; Cleveland, B. T.; Cox, G. A.; Dai, X.; Deng, H.; Detwiler, J. A.; DiMarco, M.; Diamond, M. D.; Doe, P. J.; Doucas, G.; Drouin, P.-L.; Duncan, F. A.; Dunford, M.; Earle, E. D.; Elliott, S. R.; Evans, H. C.; Ewan, G. T.; Farine, J.; Fergani, H.; Fleurot, F.; Ford, R. J.; Formaggio, J. A.; Gagnon, N.; Goon, J. TM.; Graham, K.; Guillian, E.; Habib, S.; Hahn, R. L.; Hallin, A. L.; Hallman, E. D.; Harvey, P. J.; Hazama, R.; Heintzelman, W. J.; Heise, J.; Helmer, R. L.; Hime, A.; Howard, C.; Huang, M.; Jagam, P.; Jamieson, B.; Jelley, N. A.; Jerkins, M.; Keeter, K. J.; Klein, J. R.; Kormos, L. L.; Kos, M.; Kraus, C.; Krauss, C. B.; Krueger, A.; Kutter, T.; Kyba, C. C. M.; Lange, R.; Law, J.; Lawson, I. T.; Lesko, K. T.; Leslie, J. R.; Levine, I.; Loach, J. C.; MacLellan, R.; Majerus, S.; Mak, H. B.; Maneira, J.; Martin, R.; McCauley, N.; McDonald, A. B.; McGee, S. R.; Miller, M. L.; Monreal, B.; Monroe, J.; Nickel, B. G.; Noble, A. J.; O'Keeffe, H. M.; Oblath, N. S.; Ollerhead, R. W.; Orebi Gann, G. D.; Oser, S. M.; Ott, R. A.; Peeters, S. J. M.; Poon, A. W. P.; Prior, G.; Reitzner, S. D.; Rielage, K.; Robertson, B. C.; Robertson, R. G. H.; Schwendener, M. H.; Secrest, J. A.; Seibert, S. R.; Simard, O.; Simpson, J. J.; Sinclair, D.; Skensved, P.; Sonley, T. J.; Stonehill, L. C.; Tešić, G.; Tolich, N.; Tsui, T.; Van Berg, R.; VanDevender, B. A.; Virtue, C. J.; Wall, B. L.; Waller, D.; Wan Chan Tseung, H.; Wark, D. L.; Watson, P. J. S.; Wendland, J.; West, N.; Wilkerson, J. F.; Wilson, J. R.; Wouters, J. M.; Wright, A.; Yeh, M.; Zhang, F.; Zuber, K.

    2014-03-01

    The Sudbury Neutrino Observatory (SNO) has confirmed the standard solar model and neutrino oscillations through the observation of neutrinos from the solar core. In this paper we present a search for neutrinos associated with sources other than the solar core, such as gamma-ray bursts and solar flares. We present a new method for looking for temporal coincidences between neutrino events and astrophysical bursts of widely varying intensity. No correlations were found between neutrinos detected in SNO and such astrophysical sources.

  6. Cosmic Neutrinos

    SciTech Connect

    Quigg, Chris; /Fermilab /CERN

    2008-02-01

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

  7. High energy-resolution measurement of the 82Se(3He,t )82Br reaction for double-β decay and for solar neutrinos

    NASA Astrophysics Data System (ADS)

    Frekers, D.; Alanssari, M.; Adachi, T.; Cleveland, B. T.; Dozono, M.; Ejiri, H.; Elliott, S. R.; Fujita, H.; Fujita, Y.; Fujiwara, M.; Hatanaka, K.; Holl, M.; Ishikawa, D.; Matsubara, H.; Okamura, H.; Puppe, P.; Suda, K.; Tamii, A.; Thies, J.; Yoshida, H. P.

    2016-07-01

    A high-resolution (3He,t ) charge-exchange experiment at an incident energy of 420 MeV has been performed on the double beta (β β ) decay nucleus 82Se. A detailed Gamow-Teller (GT-) strength distribution in 82Br has been extracted, which provides information to the β β -decay nuclear matrix elements. Three strong and isolated transitions, which are to the 75, 1484 and the 2087 keV states in 82Br, are found to dominate the low-excitation region below ≈2.1 MeV. Above 2.1 MeV a sudden onset of a strong GT fragmentation is observed. The degree of fragmentation resembles a situation found in the neighboring A =76 system 76Ge, whereas the observed concentration of strength in the three low-lying states is reminiscent of the heavier neighbors 96Zr and 100Mo. The strong GT transition to the 75 keV ( 1+) state makes 82Se interesting for solar neutrino detection. The 82Se(νe,e-)82Br solar neutrino capture rate in a nonoscillation scenario is therefore evaluated to 668 ±12 (stat)±60 (sys) SNU, and some of the advantages of using selenium for solar neutrino studies are discussed.

  8. Neutrino clouds and dark matter

    SciTech Connect

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

    1996-12-31

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

  9. EFFECTS OF A DEEP MIXED SHELL ON SOLAR g-MODES, p-MODES, AND NEUTRINO FLUX

    SciTech Connect

    Wolff, Charles L.

    2009-08-10

    A mixed-shell model that reflects g-modes away from the Sun's center is developed further by calibrating its parameters and evaluating a mixing mechanism: buoyancy. The shell roughly doubles g-mode oscillation periods and would explain why there is no definitive detection of their periods. But the shell has only minor effects on most p-modes. The model provides a mechanism for causing short-term fluctuations in neutrino flux and makes plausible the correlations between this flux and solar activity levels. Relations are derived for a shell heated asymmetrically by transient increases in nuclear burning in small 'hot spots'. The size of these spots and the timing of a heating event are governed by sets(l) of standing asymptotic g-modes, coupled by a maximal principle that greatly enhances their excitation and concentrates power toward the equator, assisting the detection of higher-l sets. Signals from all sets, except one, in the range 2 {<=} l {<=} 8 are identified by difference periods between consecutive radial states using the method of Garcia et al. and reinterpreting their latest spectrum. This confirms two detections of sets in a similar range of l by their rotation rates. The mean radius of shell mixing is r{sub m} = 0.16 R{sub sun}, which improves an earlier independent estimate of 0.18 by the author. The shell may cause the unexplained dip in measured sound speed at its location. Another sound speed error, centered near 0.67 R{sub sun}, and reversing flows in the same place with a period originally near 1.3 yr suggest that the g-modes are depositing there about 3% of the solar luminosity. That implies the shell at r{sub m} is receiving a similar magnitude of power, which would be enough energy to mix the corresponding shell in a standard solar model in <<10{sup 7} yr.

  10. The nylon scintillator containment vessels for the Borexino solar neutrino experiment

    NASA Astrophysics Data System (ADS)

    Cadonati, L.; Calaprice, F.; Galbiati, C.; Pocar, A.; Shutt, T.

    2014-06-01

    The neutrino event rate in the Borexino scintillator is very low ( 0.5 events per day per ton) and concentrated in an energy region well below the 2.6 MeV threshold of natural radioactivity. The intrinsic radioactive contaminants in the photomultipliers (PMTs), in the Stainless Steel Sphere, and in other detector components, play special requirements on the system required to contain the scintillator. The liquid scintillator must be shielded from the Stainless Steel Sphere and from the PMTs by a thick barrier of buffer fluid. The fluid barrier, in addition, needs to be segmented in order to contain migration of radon and daughters emanated by the Stainless Steel Sphere and by the PMTs. These requirements were met by designing and building two spherical vessel made of thin nylon film. The inner vessel contains the scintillator, separating it from the surrounding buffer. The buffer region itself is divided into two concentric shells by the second, outer nylon vessel. In addition, the two nylon vessels must satisfy stringent requirements for radioactivity and for mechanical, optical and chemical properties. This paper describes the requirements of the the nylon vessels for the Borexino experiment and offers a brief overview of the construction methods adopted to meet those requirements.

  11. Solar nutrinos

    NASA Technical Reports Server (NTRS)

    Bahcall, J. N.

    1981-01-01

    The topics covered include: an overview of the subject of solar neutrinos, a brief summary of the theory of stellar evolution, a description of the main sources of solar neutrinos, a brief summary of the results of the Brookhaven C1-37 experiment, an anaysis of the principal solar neutrino experiments, and a discussion of how solar neutrino experiments can be used to detect the collapse of stars in the Galaxy. A description of how the Ga-71 experiment can be used to decide whether the origin of the present discrepancy between theory and observation lies in conventional solar models or conventional physics is presented.

  12. Planck-scale physics and neutrino masses

    NASA Astrophysics Data System (ADS)

    Akhmedov, Evgenii Kh.; Berezhiani, Zurab G.; Senjanovic, Goran

    1992-11-01

    We discuss gravitationally induced masses and mass splittings of Majorana, Zeldovich-Konopinski-Mahmoud, and Dirac neutrinos. Among other implications, these effects can provide a solution of the solar neutrino puzzle. In particular, we show how this may work in the 17 keV neutrino picture.

  13. Neutrino Physics

    DOE R&D Accomplishments Database

    Lederman, L. M.

    1963-01-09

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

  14. Evidence for neutrino mass: A decade of discovery

    SciTech Connect

    Heeger, Karsten M.

    2004-12-08

    Neutrino mass and mixing are amongst the major discoveries of recent years. From the observation of flavor change in solar and atmospheric neutrino experiments to the measurements of neutrino mixing with terrestrial neutrinos, recent experiments have provided consistent and compelling evidence for the mixing of massive neutrinos. The discoveries at Super-Kamiokande, SNO, and KamLAND have solved the long-standing solar neutrino problem and demand that we make the first significant revision of the Standard Model in decades. Searches for neutrinoless double-beta decay probe the particle nature of neutrinos and continue to place limits on the effective mass of the neutrino. Possible signs of neutrinoless double-beta decay will stimulate neutrino mass searches in the next decade and beyond. I review the recent discoveries in neutrino physics and the current evidence for massive neutrinos.

  15. Neutrino physics

    SciTech Connect

    Harris, Deborah A.; /Fermilab

    2008-09-01

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

  16. Neutrino oscillations and the seesaw origin of neutrino mass

    NASA Astrophysics Data System (ADS)

    Miranda, O. G.; Valle, J. W. F.

    2016-07-01

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

  17. Neutrino Factories

    SciTech Connect

    Geer, Steve; /Fermilab

    2010-01-01

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

  18. EXPLOSIVE NUCLEOSYNTHESIS IN THE NEUTRINO-DRIVEN ASPHERICAL SUPERNOVA EXPLOSION OF A NON-ROTATING 15 M{sub sun} STAR WITH SOLAR METALLICITY

    SciTech Connect

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

    2011-09-01

    We investigate explosive nucleosynthesis in a non-rotating 15 M{sub sun} star with solar metallicity that explodes by a neutrino-heating supernova (SN) mechanism aided by both standing accretion shock instability (SASI) and convection. To trigger explosions in our two-dimensional hydrodynamic simulations, we approximate the neutrino transport with a simple light-bulb scheme and systematically change the neutrino fluxes emitted from the protoneutron star. By a post-processing calculation, we evaluate abundances and masses of the SN ejecta for nuclei with a mass number {<=}70, employing a large nuclear reaction network. Aspherical abundance distributions, which are observed in nearby core-collapse SN remnants, are obtained for the non-rotating spherically symmetric progenitor, due to the growth of a low-mode SASI. The abundance pattern of the SN ejecta is similar to that of the solar system for models whose masses range between (0.4-0.5) M{sub sun} of the ejecta from the inner region ({<=}10, 000 km) of the precollapse core. For the models, the explosion energies and the {sup 56}Ni masses are {approx_equal} 10{sup 51}erg and (0.05-0.06) M{sub sun}, respectively; their estimated baryonic masses of the neutron star are comparable to the ones observed in neutron-star binaries. These findings may have little uncertainty because most of the ejecta is composed of matter that is heated via the shock wave and has relatively definite abundances. The abundance ratios for Ne, Mg, Si, and Fe observed in the Cygnus loop are reproduced well with the SN ejecta from an inner region of the 15 M{sub sun} progenitor.

  19. Neutrino physics

    SciTech Connect

    Kayser, Boris; /Fermilab

    2005-06-01

    Thanks to compelling evidence that neutrinos can change flavor, we now know that they have nonzero masses, and that leptons mix. In these lectures, we explain the physics of neutrino flavor change, both in vacuum and in matter. Then, we describe what the flavor-change data have taught us about neutrinos. Finally, we consider some of the questions raised by the discovery of neutrino mass, explaining why these questions are so interesting, and how they might be answered experimentally.

  20. Neutrino Factories

    NASA Astrophysics Data System (ADS)

    Geer, Steve

    2010-06-01

    Over the last decade there has been significant progress in developing the concepts and technologies needed to produce, capture and accelerate O(1021) muons/year. This development prepares the way for a new type of neutrino source : a Neutrino Factory. This article reviews the motivation, design and R&D for a Neutrino Factory.

  1. Sterile Neutrinos

    NASA Astrophysics Data System (ADS)

    Palazzo, Antonio

    2016-05-01

    Several anomalies recorded in short-baseline neutrino experiments suggest the possibility that the standard 3-flavor framework may be incomplete and point towards a manifestation of new physics. Light sterile neutrinos provide a credible solution to these puzzling results. Here, we present a concise review of the status of the neutrino oscillations within the 3+1 scheme, the minimal extension of the standard 3-flavor framework endowed with one sterile neutrino species. We emphasize the potential role of LBL experiments in the searches of CP violation related to sterile neutrinos and their complementarity with the SBL experiments.

  2. Generalized mass ordering degeneracy in neutrino oscillation experiments

    NASA Astrophysics Data System (ADS)

    Coloma, Pilar; Schwetz, Thomas

    2016-09-01

    We consider the impact of neutral-current (NC) nonstandard neutrino interactions (NSI) on the determination of the neutrino mass ordering. We show that in the presence of NSI there is an exact degeneracy which makes it impossible to determine the neutrino mass ordering and the octant of the solar mixing angle θ12 at oscillation experiments. The degeneracy holds at the probability level and for arbitrary matter density profiles, and hence solar, atmospheric, reactor, and accelerator neutrino experiments are affected simultaneously. The degeneracy requires order-1 corrections from NSI to the NC electron neutrino-quark interaction and can be tested in electron neutrino NC scattering experiments.

  3. Supernova neutrinos and explosive nucleosynthesis

    SciTech Connect

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

    2014-05-09

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

  4. Resonances in (11)C observed in the (4)He((7)Be, alpha)(7)Be and (4)He((7)Be, p)(10)B reactions

    SciTech Connect

    Freer, M.; Ashwood, N. I.; Curtis, N.; Malcolm, J.; Munoz-Britton, T.; Price, D.; Wheldon, C.; Achouri, N. L.; Demaret, P.; Bardayan, Daniel W; Pain, Steven D; Brown, S.; Catford, W.; Harlin, Christopher W; Thomas, J. S.; Wilson, G.; Chipps, K.; Milin, M.; Raabe, R.; Soic, N.

    2012-01-01

    Measurements of the {sup 4}He({sup 7}Be,{alpha}){sup 7}Be and {sup 4}He({sup 7}Be,p){sup 10}B reactions were performed using {sup 7}Be beam energies of 7.1 and 23 MeV and a helium-4 target, employing the thick target technique. Resonances were observed between E{sub x}({sup 11}C) = 8.6 to 13.8 MeV. An R-matrix analysis was performed to characterize the spins and partial widths. This analysis showed that the observed sequence of states was consistent with that found for {sup 7}Li + {alpha} resonant scattering populating resonances in {sup 11}B. A comparison of the proposed partial widths for decay with the Wigner limit indicates that several of the states are associated with cluster-like structures.

  5. Low energy neutrinos in Super-Kamiokande

    NASA Astrophysics Data System (ADS)

    Sekiya, Hiroyuki

    2016-05-01

    Super-Kamiokande (SK), a 50 kton water Cherenkov detector, observes 8B solar neutrinos via neutrino-electron elastic scattering. The analysis threshold was successfully lowered to 3.5 MeV (recoil electron kinetic energy) in SK-IV. To date SK has observed solar neutrinos for 18 years. An analysis regarding possible correlations between the solar neutrino flux and the 11 year solar activity cycle is shown. With large statistics, SK searches for distortions of the solar neutrino energy spectrum caused by the MSW resonance in the core of the sun. SK also searches for a day/night solar neutrino flux asymmetry induced by the matter in the Earth. The Super-Kamiokande Gd (SK-Gd) project is the upgrade of the SK detector via the addition of water-soluble gadolinium (Gd) salt. This modification will enable it to efficiently identify low energy anti-neutrinos. SK-Gd will pursue low energy physics currently inaccessible to SK due to backgrounds. The most important will be the world’s first observation of the diffuse supernova neutrino background. The main R&D program towards SK-Gd is EG ADS: a 200 ton, fully instrumented tank built in a new cavern in the Kamioka mine.

  6. Neutrino factory

    DOE PAGES

    Bogomilov, M.; Matev, R.; Tsenov, R.; Dracos, M.; Bonesini, M.; Palladino, V.; Tortora, L.; Mori, Y.; Planche, T.; Lagrange, J. B.; et al

    2014-12-08

    The properties of the neutrino provide a unique window on physics beyond that described by the standard model. The study of subleading effects in neutrino oscillations, and the race to discover CP-invariance violation in the lepton sector, has begun with the recent discovery that theta(13) > 0. The measured value of theta(13) is large, emphasizing the need for a facility at which the systematic uncertainties can be reduced to the percent level. The neutrino factory, in which intense neutrino beams are produced from the decay of muons, has been shown to outperform all realistic alternatives and to be capable ofmore » making measurements of the requisite precision. Its unique discovery potential arises from the fact that only at the neutrino factory is it practical to produce high-energy electron (anti) neutrino beams of the required intensity. This paper presents the conceptual design of the neutrino factory accelerator facility developed by the European Commission Framework Programme 7 EURO nu. Design Study consortium. EURO nu coordinated the European contributions to the International Design Study for the Neutrino Factory (the IDS-NF) collaboration. The EURO nu baseline accelerator facility will provide 10(21) muon decays per year from 12.6 GeV stored muon beams serving a single neutrino detector situated at a source-detector distance of between 1 500 km and 2 500 km. A suite of near detectors will allow definitive neutrino-scattering experiments to be performed.« less

  7. Neutrino factory

    SciTech Connect

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

    2014-12-08

    The properties of the neutrino provide a unique window on physics beyond that described by the standard model. The study of subleading effects in neutrino oscillations, and the race to discover CP-invariance violation in the lepton sector, has begun with the recent discovery that theta(13) > 0. The measured value of theta(13) is large, emphasizing the need for a facility at which the systematic uncertainties can be reduced to the percent level. The neutrino factory, in which intense neutrino beams are produced from the decay of muons, has been shown to outperform all realistic alternatives and to be capable of making measurements of the requisite precision. Its unique discovery potential arises from the fact that only at the neutrino factory is it practical to produce high-energy electron (anti) neutrino beams of the required intensity. This paper presents the conceptual design of the neutrino factory accelerator facility developed by the European Commission Framework Programme 7 EURO nu. Design Study consortium. EURO nu coordinated the European contributions to the International Design Study for the Neutrino Factory (the IDS-NF) collaboration. The EURO nu baseline accelerator facility will provide 10(21) muon decays per year from 12.6 GeV stored muon beams serving a single neutrino detector situated at a source-detector distance of between 1 500 km and 2 500 km. A suite of near detectors will allow definitive neutrino-scattering experiments to be performed.

  8. Neutrino factory

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

    The properties of the neutrino provide a unique window on physics beyond that described by the standard model. The study of subleading effects in neutrino oscillations, and the race to discover CP-invariance violation in the lepton sector, has begun with the recent discovery that θ13>0 . The measured value of θ13 is large, emphasizing the need for a facility at which the systematic uncertainties can be reduced to the percent level. The neutrino factory, in which intense neutrino beams are produced from the decay of muons, has been shown to outperform all realistic alternatives and to be capable of making measurements of the requisite precision. Its unique discovery potential arises from the fact that only at the neutrino factory is it practical to produce high-energy electron (anti)neutrino beams of the required intensity. This paper presents the conceptual design of the neutrino factory accelerator facility developed by the European Commission Framework Programme 7 EURO ν Design Study consortium. EURO ν coordinated the European contributions to the International Design Study for the Neutrino Factory (the IDS-NF) collaboration. The EURO ν baseline accelerator facility will provide 1 021 muon decays per year from 12.6 GeV stored muon beams serving a single neutrino detector situated at a source-detector distance of between 1 500 km and 2 500 km. A suite of near detectors will allow definitive neutrino-scattering experiments to be performed.

  9. Neutrino oscillations in noisy media

    SciTech Connect

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

    1994-05-27

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

  10. Neutrino Oscillations With Two Sterile Neutrinos

    NASA Astrophysics Data System (ADS)

    Kisslinger, Leonard S.

    2016-10-01

    This work estimates the probability of μ to e neutrino oscillation with two sterile neutrinos using a 5×5 U-matrix, an extension of the previous estimate with one sterile neutrino and a 4×4 U-matrix. The sterile neutrino-active neutrino mass differences and the mixing angles of the two sterile neutrinos with the three active neutrinos are taken from recent publications, and the oscillation probability for one sterile neutrino is compared to the previous estimate.

  11. Neutrino Oscillations With Two Sterile Neutrinos

    NASA Astrophysics Data System (ADS)

    Kisslinger, Leonard S.

    2016-06-01

    This work estimates the probability of μ to e neutrino oscillation with two sterile neutrinos using a 5×5 U-matrix, an extension of the previous estimate with one sterile neutrino and a 4×4 U-matrix. The sterile neutrino-active neutrino mass differences and the mixing angles of the two sterile neutrinos with the three active neutrinos are taken from recent publications, and the oscillation probability for one sterile neutrino is compared to the previous estimate.

  12. Three dimensional calculation of flux of low energy atmospheric neutrinos

    NASA Technical Reports Server (NTRS)

    Lee, H.; Bludman, S. A.

    1985-01-01

    Results of three-dimensional Monte Carlo calculation of low energy flux of atmospheric neutrinos are presented and compared with earlier one-dimensional calculations 1,2 valid at higher neutrino energies. These low energy neutrinos are the atmospheric background in searching for neutrinos from astrophysical sources. Primary cosmic rays produce the neutrino flux peaking at near E sub=40 MeV and neutrino intensity peaking near E sub v=100 MeV. Because such neutrinos typically deviate by 20 approximately 30 from the primary cosmic ray direction, three-dimensional effects are important for the search of atmospheric neutrinos. Nevertheless, the background of these atmospheric neutrinos is negligible for the detection of solar and supernova neutrinos.

  13. Progress in the Physics of Massive Neutrinos

    NASA Astrophysics Data System (ADS)

    BARGER, V.; MARFATIA, D.; WHISNANT, K.

    The current status of the physics of massive neutrinos is reviewed with a forward-looking emphasis. The article begins with the general phenomenology of neutrino oscillations in vacuum and matter and documents the experimental evidence for oscillations of solar, reactor, atmospheric and accelerator neutrinos. Both active and sterile oscillation possibilities are considered. The impact of cosmology (BBN, CMB, leptogenesis) and astrophysics (supernovae, highest energy cosmic rays) on neutrino observables and vice versa, is evaluated. The predictions of grand unified, radiative and other models of neutrino mass are discussed. Ways of determining the unknown parameters of three-neutrino oscillations are assessed, taking into account eight-fold degeneracies in parameters that yield the same oscillation probabilities, as well as ways to determine the absolute neutrino mass scale (from beta-decay, neutrinoless double-beta decay, large scale structure and Z-bursts). Critical unknowns at present are the amplitude of νμ→νe oscillations and the hierarchy of the neutrino mass spectrum; the detection of CP violation in the neutrino sector depends on these and on an unknown phase. The estimated neutrino parameter sensitivities at future facilities (reactors, superbeams, neutrino factories) are given. The overall agenda of a future neutrino physics program to construct a bottom-up understanding of the lepton sector is presented.

  14. Neutrino mass

    SciTech Connect

    Bowles, T.J.

    1994-04-01

    The existence of a finite neutrino mass would have important consequences in particle physics, astrophysics, and cosmology. Experimental sensitivities have continued to be pushed down without any confirmed evidence for a finite neutrino mass. Yet there are several observations of discrepancies between theoretical predictions and observations which might be possible indications of a finite neutrino mass. Thus, extensive theoretical and experimental work is underway to resolve these issues.

  15. Updating neutrino magnetic moment constraints

    NASA Astrophysics Data System (ADS)

    Cañas, B. C.; Miranda, O. G.; Parada, A.; Tórtola, M.; Valle, J. W. F.

    2016-02-01

    In this paper we provide an updated analysis of the neutrino magnetic moments (NMMs), discussing both the constraints on the magnitudes of the three transition moments Λi and the role of the CP violating phases present both in the mixing matrix and in the NMM matrix. The scattering of solar neutrinos off electrons in Borexino provides the most stringent restrictions, due to its robust statistics and the low energies observed, below 1 MeV. Our new limit on the effective neutrino magnetic moment which follows from the most recent Borexino data is 3.1 ×10-11μB at 90% C.L. This corresponds to the individual transition magnetic moment constraints: |Λ1 | ≤ 5.6 ×10-11μB, |Λ2 | ≤ 4.0 ×10-11μB, and |Λ3 | ≤ 3.1 ×10-11μB (90% C.L.), irrespective of any complex phase. Indeed, the incoherent admixture of neutrino mass eigenstates present in the solar flux makes Borexino insensitive to the Majorana phases present in the NMM matrix. For this reason we also provide a global analysis including the case of reactor and accelerator neutrino sources, presenting the resulting constraints for different values of the relevant CP phases. Improved reactor and accelerator neutrino experiments will be needed in order to underpin the full profile of the neutrino electromagnetic properties.

  16. Atmospheric neutrinos and discovery of neutrino oscillations.

    PubMed

    Kajita, Takaaki

    2010-01-01

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

  17. Atmospheric neutrinos and discovery of neutrino oscillations

    PubMed Central

    Kajita, Takaaki

    2010-01-01

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

  18. An ''archaeological'' quest for galactic supernova neutrinos

    SciTech Connect

    Lazauskas, Rimantas; Volpe, Cristina E-mail: Cecilia.Lunardini@asu.edu

    2009-04-15

    We explore the possibility to observe the effects of electron neutrinos from past galactic supernovae, through a geochemical measurement of the amount of Technetium 97 produced by neutrino-induced reactions in a Molybdenum ore. The calculations we present take into account the recent advances in our knowledge of neutrino interactions, of neutrino oscillations inside a supernova, of the solar neutrino flux at Earth and of possible failed supernovae. The predicted Technetium 97 abundance is of the order of 10{sup 7} atoms per 10 kilotons of ore, which is close to the current geochemical experimental sensitivity. Of this, {approx} 10-20% is from supernovae. Considering the comparable size of uncertainties, more precision in the modeling of neutrino fluxes as well as of neutrino cross sections is required for a meaningful measurement.

  19. Atmospheric neutrino problem in maximally-mixed three generations of neutrinos

    NASA Astrophysics Data System (ADS)

    Giunti, C.; Kim, C. W.; Kim, J. D.

    1995-02-01

    Motivated by the indication that both the atmospheric and the solar neutrino puzzles may simultaneously be solved by (vacuum as well as matter-induced resonant) oscillations of two generations of neutrinos with large mixing, we have analyzed the data on the atmospheric and solar neutrinos assuming that all three neutrinos are maximally mixed. It is shown that the values of Δm2 obtained from the two-generation analyses are still valid even in the three-generation scheme, i.e. the two puzzles can be solved simultaneously if Δm231 ~= 10-2eV2 for the atmospheric neutrinos and Δm221 ~= 10-10eV2 for solar neutrinos in the maximally mixed three-generation scheme.

  20. Experimental evidence of electron neutrino oscillations and validation of MSW-LMA model with Borexino

    NASA Astrophysics Data System (ADS)

    Avanzini, M. Buizza

    2011-04-01

    We report the real time measurements of 7Be and 8B solar neutrino fluxes performed with the Borexino experiment at the Laboratori Nazionali del Gran Sasso. The achievement of these measurements was possible thanks to the excellent levels of the radiopurity reached. The measurement of the 7Be in real time is the first direct measurements of the survival probability for solar electron neutrinos in the vacuum region. For 8B we reached a threshold energy of 3MeV which is the lowest achieved so far in real time. For the first time, the same apparatus can measure two different oscillation regions (vacuum-driven and matter-enhanced) predicted by the MSW-LMA model. Borexino also quotes the ratio between the survival probabilities, corresponding to 1.93 ± 0.75, and validates the presence of the transition region between the two oscillation regimes, according to the MSW-LMA solution.In addition, a preliminary result on the Day-Night Asymmetry (ADN) for the 7Be neutrino flux is presented and corresponds to 0.007 ± 0.073. This measurement makes Borexino able to give once more an independent confirmation of the MSW-LMA solution.

  1. 3He(α,γ)7Be cross section measured using complementary techniques

    NASA Astrophysics Data System (ADS)

    Carmona-Gallardo, M.; Rojas, A.; Borge, M. J. G.; Davids, B.; Fulton, B. R.; Hass, M.; Nara Singh, B. S.; Ruiz, C.; Tengblad, O.

    2014-03-01

    The astrophysical S-factor for the 3He(α,γ)7Be reaction plays an important role in the Solar Standard Model and in the Big Bang Nucleosynthesis scenario. The advances from two recent experiments performed using complementary techniques at center of mass (C.M.) energies between 1 and 3 MeV are discussed.

  2. Supernova neutrinos, neutral currents and the origin of fluorine

    NASA Technical Reports Server (NTRS)

    Woosley, S. E.; Haxton, W. C.

    1988-01-01

    An argument is made for the existence of a significant role for neutrinos in the nuclear chemistry of an exploding supernova. Emphasis is given to the neutrino-induced nucleosynthesis of fluorine. It is shown that fluorine's solar abundance constrains the temperature of muon and tauon neutrinos to values near what is expected from the standard model.

  3. Neutrino telescopes

    SciTech Connect

    Costantini, H.

    2012-09-15

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

  4. Measurement of day and night neutrino energy spectra at SNO and constraints on neutrino mixing parameters.

    PubMed

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

    2002-07-01

    The Sudbury Neutrino Observatory (SNO) has measured day and night solar neutrino energy spectra and rates. For charged current events, assuming an undistorted 8B spectrum, the night minus day rate is 14.0%+/-6.3%(+1.5%)(-1.4%) of the average rate. If the total flux of active neutrinos is additionally constrained to have no asymmetry, the nu(e) asymmetry is found to be 7.0%+/-4.9%(+1.3%)(-1.2%). A global solar neutrino analysis in terms of matter-enhanced oscillations of two active flavors strongly favors the large mixing angle solution.

  5. Neutrino factories

    SciTech Connect

    Soler, F. J. P.

    2015-07-15

    The Neutrino Factory is a facility that produces neutrino beams with a well-defined flavour content and energy spectrum from the decay of intense, high-energy, stored muon beams to establish CP violation in the neutrino sector. The International Design Study for the Neutrino Factory (the IDS-NF) is providing a Reference Design Report (RDR) for the facility. The present design is optimised for the recent measurements of θ{sub 13}. The accelerator facility will deliver 10{sup 21} muon decays per year from 10 GeV stored muon beams. The straight sections of the storage ring point to a 100 kton Magnetised Iron Neutrino Detector (MIND) at a distance of 2000-2500 km from the source. The accuracy in the value of δ{sub CP} that a Neutrino Factory can achieve and the δ{sub CP} coverage is unrivalled by other future facilities. Staging scenarios for the Neutrino Factory deliver facilities that can carry out physics at each stage. In the context of Fermilab, such a scenario would imply in the first stage the construction of a small storage ring, nuSTORM, to carry out neutrino cross-section and sterile neutrino measurements and to perform a programme of 6D muon cooling R&D. The second stage is the construction of a 5 GeV Neutrino Factory (nuMAX) pointing to the Sanford Underground Research Facility at Homestake and the final stage would use many of the components of this facility to construct a Muon Collider, initially as a 126 GeV CM Higgs Factory, which may be upgraded to a multi-TeV Muon Collider if required.

  6. Neutrino Oscillations: Eighty Years in Review

    NASA Astrophysics Data System (ADS)

    Bowers, Rebecca Lyn

    In order to discuss neutrino oscillations, it is necessary to have knowledge of the developments in the field spanning the last eighty years. The existence of the neutrino was posited by Wolfgang Pauli in 1930 to account for the mass defect in beta decay, and to this day physicists are still endeavoring to answer fundamental questions about this enigmatic particle. The scope of this thesis includes a historical background of neutrino physics and a discussion of neutrinos and the Standard Model; subsequent to this is a discussion of the Solar Neutrino Problem, which provided the impetus for the proposal of neutrino oscillations. Bolstering the theory of neutrino oscillations (which is developed in the body of this thesis) are neutrino detector experiments and their results; these include the Homestake experiment, SNO, Kamiokande and Super-Kamiokande, MINOS, and Double-Chooz. We also include relevant derivations, most particularly of the quantum mechanics of neutrino oscillations as treated in the wave packet formalism. We have amassed here the principle theories and experimental results -- a mere tip of the iceberg -- that have brought us to our current understanding of neutrino oscillations. We have also studied the quantum mechanics of neutrino oscillations and developed for ourselves the wave packet formalism describing the phenomenon.

  7. Neutrino radiation hazards: A paper tiger

    SciTech Connect

    Cossairt, J.D.; Grossman, N.L.; Marshall, E.T.

    1996-09-01

    Neutrinos are present in the natural environment due to terrestrial, solar, and cosmic sources and are also produced at accelerators both incidentally and intentionally as part of physics research programs. Progress in fundamental physics research has led to the creation of beams of neutrinos of ever-increasing intensity and/or energy. The large size and cost associated with these beams attracts, and indeed requires, public interest, support, and some understanding of the `exotic` particles produced, including the neutrinos. Furthermore, the very word neutrino (`little neutral one`, as coined by Enrico Fermi) can lead to public concern due to confusion with `neutron`, a word widely associated with radiological hazards. Adding to such possible concerns is a recent assertion, widely publicized, that neutrinos from astronomical events may have led to the extinction of some biological species. Presented here are methods for conservatively estimating the dose equivalent due to neutrinos as well as an assessment of the possible role of neutrinos in biological extinction processes. It is found that neutrinos produced by the sun and modern particle accelerators produce inconsequential dose equivalent rates. Examining recent calculations concerning neutrinos incident upon the earth due to stellar collapse, it is concluded that it is highly unlikely that these neutrinos caused the mass extinctions of species found in the paleontological record. Neutrino radiation hazards are, then, truly a `paper tiger`. 14 refs., 1 fig., 1 tab.

  8. New Prospects for Real-Time Spectroscopy of Low Energy Electron Neutrinos from the Sun

    NASA Astrophysics Data System (ADS)

    Raghavan, R. S.

    1997-05-01

    Flavor-specific real-time spectroscopy of solar electron neutrinos \\(νe\\) from the p+p, 7Be+e-, and CNO reactions in the Sun may become practical for the first time via a newly discovered class of νe reactions. Highly specific signatures of νe capture by the targets 176Yb, 160Gd, or 82Se can discriminate against a background ~107 times larger than the νe signals. A high-quality liquid scintillator containing up to ~15 wt % Yb has been developed for observing these νe reactions. Experiments based on the new approach can, in principle, resolve basic puzzles set by current solar neutrino results and the underlying question of νe-flavor conversion.

  9. Neutrino detection with CLEAN

    NASA Astrophysics Data System (ADS)

    McKinsey, D. N.; Coakley, K. J.

    2005-01-01

    This article describes CLEAN, an approach to the detection of low-energy solar neutrinos and neutrinos released from supernovae. The CLEAN concept is based on the detection of elastic scattering events (neutrino-electron scattering and neutrino-nuclear scattering) in liquified noble gases such as liquid helium, liquid neon, and liquid xenon, all of which scintillate brightly in the ultraviolet. Key to the CLEAN technique is the use of a thin film of wavelength-shifting fluor to convert the ultraviolet scintillation light to the visible, thereby allowing detection by conventional photomultipliers. Liquid neon is a particularly promising medium for CLEAN. Because liquid neon has a high scintillation yield, has no long-lived radioactive isotopes, and can be easily purified by use of cold traps, it is an ideal medium for the detection of rare nuclear events. In addition, neon is inexpensive, dense, and transparent to its own scintillation light, making it practical for use in a large self-shielding apparatus. The central region of a full-sized detector would be a stainless steel tank holding approximately 135 metric tons of liquid neon. Inside the tank and suspended in the liquid neon would be several thousand photomultipliers. Monte Carlo simulations of gamma ray backgrounds have been performed assuming liquid neon as both shielding and detection medium. Gamma ray events occur with high probability in the outer parts of the detector. In contrast, neutrino scattering events occur uniformly throughout the detector. We discriminate background gamma ray events from events of interest based on a spatial maximum likelihood method estimate of event location. Background estimates for CLEAN are presented, as well as an evaluation of the sensitivity of the detector for p-p neutrinos. Given these simulations, the physics potential of the CLEAN approach is evaluated.

  10. Experimental Anomalies in Neutrino Physics

    NASA Astrophysics Data System (ADS)

    Palamara, Ornella

    2014-03-01

    In recent years, experimental anomalies ranging in significance (2.8-3.8 σ) have been reported from a variety of experiments studying neutrinos over baselines less than 1 km. Results from the LSND and MiniBooNE short-baseline νe /νe appearance experiments show anomalies which cannot be described by oscillations between the three standard model neutrinos (the ``LSND anomaly''). In addition, a re-analysis of the anti-neutrino flux produced by nuclear power reactors has led to an apparent deficit in νe event rates in a number of reactor experiments (the ``reactor anomaly''). Similarly, calibration runs using 51Cr and 37Ar radioactive sources in the Gallium solar neutrino experiments GALLEX and SAGE have shown an unexplained deficit in the electron neutrino event rate over very short distances (the ``Gallium anomaly''). The puzzling results from these experiments, which together may suggest the existence of physics beyond the Standard Model and hint at exciting new physics, including the possibility of additional low-mass sterile neutrino states, have raised the interest in the community for new experimental efforts that could eventually solve this puzzle. Definitive evidence for sterile neutrinos would be a revolutionary discovery, with implications for particle physics as well as cosmology. Proposals to address these signals by employing accelerator, reactor and radioactive source experiments are in the planning stages or underway worldwide. In this talk some of these will be reviewed, with emphasis on the accelerator programs.

  11. Search for Neutrinos from the Sun

    DOE R&D Accomplishments Database

    Davis, Raymond Jr.

    1968-09-01

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

  12. Evidence for neutrino oscillations in the Sudbury Neutrino Observatory

    SciTech Connect

    Marino, Alysia Diane

    2004-01-01

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

  13. Factors influencing 7Be accumulation on rock varnish

    NASA Astrophysics Data System (ADS)

    Moore, Willard S.; Liu, Tanzhuo; Broecker, Wallace S.; Finkel, Robert C.; Wright, Allen

    Rocks coated with desert varnish were translocated from Scottsdale, Arizona, and Panamint Valley, California, to a fenced-in plot near Biosphere 2 where they were allowed to accumulate a new crop of the 53 day half life, cosmic ray-produced 7Be. Those exposed to precipitation accumulated several times more of this isotope than those shielded from precipitation. No significant difference in 7Be accumulation was observed between a set which was UV irradiated (in an attempt to kill resident bacteria) and a set which received no UV irradiation. This experiment suggests that 62 ± 10 percent of the beryllium accumulated on the varnish was supplied by precipitation and 38 ± 10 percent by some combination of dew, dust, and aerosols. If bacteria are, as has been proposed, responsible for varnish growth, then either our UV irradiation was inadequate to squelch their activity or the 7Be we measured had not yet been built into the varnish.

  14. Neutrino oscillations.

    PubMed

    Thomson, Mark

    2002-05-15

    The wave theory of light, and in particular the principle of interference, was formulated by Thomas Young in 1801. In the 20th century, the principle of interference was extended to the quantum mechanical wave functions describing matter. The phenomenon of quantum mechanical interference of different neutrino states, neutrino oscillations, has provided one of the most exciting developments in high energy particle physics of the last decade. Observations of the flavour oscillations of neutrinos produced by distant sources, such as from the core of the Sun, provide compelling evidence that neutrinos have mass. This article describes the main features and the most significant experimental observations of this unusual application of the principle of interference.

  15. Neutrino astrophysics with Hyper-Kamiokande

    NASA Astrophysics Data System (ADS)

    Yano, Takatomi; Hyper-Kamiokande proto Collaboration

    2016-05-01

    Hyper-Kamiokande (Hyper-K) is a proposed next generation underground large water Cherenkov detector. The detector consists of 1 Mt pure water tank with surrounding 99,000 newly developed photo sensors, providing fiducial volume of 0.56 Mt. The energies, positions and directions of charged particles produced by neutrino interactions are detected using its Cherenkov light in water. Our detector will be located at deep underground to reduce the cosmic muon flux and its spallation products, which is a dominant background at the low energy analysis. Hyper-K will play a considerable role in the next neutrino physics frontier, even in the neutrino astrophysics. The detection with large statistics of astrophysical neutrons, i.e., solar neutrino, supernova burst neutrino and supernova relic neutrino, will be remarkable information for both of particle physics and astrophysics.

  16. Planck scale effects in neutrino physics

    NASA Astrophysics Data System (ADS)

    Akhmedov, E. K.; Senjanovic, G.; Tao, Zhi-Jan; Berezhiani, Z. G.

    1992-08-01

    We study the phenomenology and cosmology of the Majoron (flavon) models of one inert neutrino and three active ones. We pay special attention to the possible (almost) conserved generalization of the Zeldovich-Konopinski-Mahmoud lepton charge. Using Planck scale physics effects, which provide the breaking of the lepton charge, we show how, in this picture, one can incorporate the solutions to some of the central issues in neutrino physics, such as the solar and atmospheric neutrino puzzles, dark matter, and a 17 keV neutrino. These gravitation effects induce tiny Majorana mass terms for neutrinos and considerable masses for flavons. The cosmological demand for the sufficiently fast decay of flavons implies a lower limit on the electron neutrino mass in the range of 0.1-1 eV.

  17. Planck scale effects in neutrino physics

    NASA Astrophysics Data System (ADS)

    Akhmedov, Eugeni Kh.; Berezhiani, Zurab G.; Senjanović, Goran; Tao, Zhijian

    1993-04-01

    We study the phenomenology and cosmology of the Majoron (flavon) models of three active and one inert neutrino paying special attention to the possible (almost) conserved generalization of the Zeldovich-Konopinski-Mahmoud lepton charge. Using Planck scale physics effects which provide the breaking of the lepton charge, we show how in this picture one can incorporate the solutions to some of the central issues in neutrino physics such as the solar and atmospheric neutrino puzzles and the dark matter problem with the possible existence of a heavy (1-10 keV) neutrino. These gravitational effects induce tiny Majorana mass terms for neutrinos and considerable masses for flavons. The cosmological demand for the sufficiently fast decay of flavons implies a lower limit on the electron-neutrino mass in the range of 0.1-1 eV.

  18. A new capability for ANTARES: 7Be by AMS for ice samples

    NASA Astrophysics Data System (ADS)

    Smith, A. M.; Mokhber-Shahin, L.; Simon, K. J.

    2013-01-01

    ANSTO, in collaboration with the Australian Antarctic Division (AAD) and the Antarctic Climate and Ecosystems Cooperative Research Centre (ACE CRC), has an on-going program of 10Be (t½ = 1.39 × 106 a) concentration measurement in firn and ice at Law Dome, Antarctica. In recent years snow pit samples have also been measured for 7Be (t½ = 53.28 d) concentration as this isotope has the potential to give further insight into the transport and deposition of cosmogenic beryllium to Law Dome and so improve the use of 10Be as a proxy for solar activity. Early 7Be measurements were made by gamma-ray spectrometry (GRS) with typical counting times of 3 days. In 2010, we developed the capability for 7Be/9Be measurement on the 10 MV ANTARES (Australian National Tandem Accelerator for Applied Research) accelerator using carbon foil post-stripping of 7Be3+ to 7Be4+ to eliminate the 7Li isobar. We describe the method and explain the advantages of using accelerator mass spectrometry (AMS) over GRS for 7Be analysis.

  19. 7-Be Implantation in Plastics for Prosthesis Wear Studies

    NASA Astrophysics Data System (ADS)

    Greife, Uwe; Erikson, L.; Patel, N.; Wimmer, M.; Dwiwedi, Y.; Laurent, M.; Chipps, K.; Blackmon, J.; Kozub, R.; Bardayan, D.; Gross, C.; Stracener, D.; Smith, M.; Nesaraya, C.; Rehm, E.; Ahmed, I.; Greene, J.

    2010-11-01

    The current generation of highly cross linked ultrahigh molecular weight polyethylenes (PE) for hip and knee joint replacement have achieved such low in vitro wear rates that efforts have been underway to develop more sensitive methods to measure polyethylene wear. The most widely used technique, the gravimetric method, suffers from the notable disadvantage that mass gain by fluid absorption can considerably exceed mass loss by wear, making the wear measurement inaccurate, sometimes even leading to negative ``wear'' values. The purpose of this experiment was to investigate the use of a radioactive tracer, beryllium-7 (7-Be), to circumvent the problem of fluid absorption and thereby achieve a much more sensitive and accurate wear measurement. This proof of principle study demonstrated the general feasibility of 7-Be implantation (performed at the Holifield Radioactive Ion Beam Facility of Oak Ridge National Laboratory) for PE wear analysis.

  20. Production and separation of carrier-free 7Be

    DOE PAGES

    Gharibyan, N.; Moody, K. J.; Tumey, S. J.; Brown, T. A.; Despotopulos, J. D.; Faye, S. A.; Roberts, K. E.; Shaughnessy, D. A.

    2015-10-24

    A high-purity carrier-free 7Be was efficiently isolated following proton bombardment of a lithium hydroxide - aluminum target. The separation of beryllium from lithium and aluminum was achieved through a hydrochloric acid elution system utilizing cation exchange chromatography. The beryllium recovery, +99%, was assessed through gamma spectroscopy while the chemical purity was established by mass spectrometry. In conclusion, the decontamination factors of beryllium from lithium and aluminum were determined to be 6900 and 300, respectively.

  1. Neutrino mass and mixing in the seesaw playground

    NASA Astrophysics Data System (ADS)

    King, Stephen F.

    2016-07-01

    We discuss neutrino mass and mixing in the framework of the classic seesaw mechanism, involving right-handed neutrinos with large Majorana masses, which provides an appealing way to understand the smallness of neutrino masses. However, with many input parameters, the seesaw mechanism is in general not predictive. We focus on natural implementations of the seesaw mechanism, in which large cancellations do not occur, where one of the right-handed neutrinos is dominantly responsible for the atmospheric neutrino mass, while a second right-handed neutrino accounts for the solar neutrino mass, leading to an effective two right-handed neutrino model. We discuss recent attempts to predict lepton mixing and CP violation within such natural frameworks, focusing on the Littlest Seesaw and its distinctive predictions.

  2. Reaction dynamics studies for the system 7Be+58Ni

    NASA Astrophysics Data System (ADS)

    Torresi, D.; Mazzocco, M.; Acosta, L.; Boiano, A.; Boiano, C.; Diaz-Torres, A.; Fierro, N.; Glodariu, T.; Grilj, L.; Guglielmetti, A.; Keeley, N.; La Commara, M.; Martel, I.; Mazzocchi, C.; Molini, P.; Pakou, A.; Parascandolo, C.; Parkar, V. V.; Patronis, N.; Pierroutsakou, D.; Romoli, M.; Rusek, K.; Sanchez-Benitez, A. M.; Sandoli, M.; Signorini, C.; Silvestri, R.; Soramel, F.; Stiliaris, E.; Strano, E.; Stroe, L.; Zerva, K.

    2015-04-01

    The study of reactions induced by exotic weakly bound nuclei at energies around the Coulomb barrier had attracted a large interest in the last decade, since the features of these nuclei can deeply affect the reaction dynamics. The discrimination between different reaction mechanisms is, in general, a rather difficult task. It can be achieved by using detector arrays covering high solid angle and with high granularity that allow to measure the reaction products and, possibly, coincidences between them, as, for example, recently done for stable weakly bound nuclei [1, 2]. We investigated the collision of the weakly bound nucleus 7Be on a 58Ni target at the beam energy of 1.1 times the Coulomb barrier, measuring the elastic scattering angular distribution and the energy and angular distributions of 3He and 4He. The 7Be radioactive ion beam was produced by the facility EXOTIC at INFN-LNL with an energy of 22 MeV and an intensity of ~3×105 pps. Results showed that the 4He yeld is about 4 times larger than 3He yield, suggesting that reaction mechanisms other than the break-up mostly produce the He isotopes. Theoretical calculations for transfer channels and compound nucleus reactions suggest that complete fusion accounts for (41±5%) of the total reaction cross section extracted from optical model analysis of the elastic scattering data, and that 3He and 4He stripping are the most populated reaction channels among direct processes. Eventually estimation of incomplete fusion contributions to the 3,4He production cross sections was performed through semi-classical calculations with the code PLATYPUS [3].

  3. Near maximal atmospheric neutrino mixing in neutrino mass models with two texture zeros

    NASA Astrophysics Data System (ADS)

    Dev, S.; Gautam, R. R.; Singh, Lal; Gupta, Manmohan

    2014-07-01

    The implications of a large value of the effective Majorana neutrino mass for a class of two texture zero neutrino mass matrices have been studied in the flavor basis. It is found that these textures predict a near maximal atmospheric neutrino mixing angle in the limit of a large effective Majorana neutrino mass. It is noted that this prediction is independent of the values of solar and reactor neutrino mixing angles. We present the symmetry realization of these textures using the discrete cyclic group Z3. It is found that the texture zeros realized in this work remain stable under renormalization group running of the neutrino mass matrix from the seesaw scale to the electroweak scale, at one-loop level.

  4. Neutrino refraction by the cosmic neutrino background

    NASA Astrophysics Data System (ADS)

    Díaz, J. S.; Klinkhamer, F. R.

    2016-03-01

    We have determined the dispersion relation of a neutrino test particle propagating in the cosmic neutrino background. Describing the relic neutrinos and antineutrinos from the hot big bang as a dense medium, a matter potential or refractive index is obtained. The vacuum neutrino mixing angles are unchanged, but the energy of each mass state is modified. Using a matrix in the space of neutrino species, the induced potential is decomposed into a part which produces signatures in beta-decay experiments and another part which modifies neutrino oscillations. The low temperature of the relic neutrinos makes a direct detection extremely challenging. From a different point of view, the identified refractive effects of the cosmic neutrino background constitute an ultralow background for future experimental studies of nonvanishing Lorentz violation in the neutrino sector.

  5. Neutrino-nucleus scattering off 136Xe

    NASA Astrophysics Data System (ADS)

    Ydrefors, E.; Suhonen, J.; Zhao, Y. M.

    2015-01-01

    Background: Theoretical estimates of the cross sections for the neutrino-nucleus scattering off relevant nuclei for supernova neutrinos are essential for many applications in neutrino physics and astrophysics. The double-β -decaying nucleus 136Xe nucleus is used by the EXO Collaboration in the search for neutrinoless double-β decay. A ton-scale experiment based on 136Xe could also be used for studies of supernova neutrinos and/or solar neutrinos. Purpose: The purpose of the present work is, thus, to perform a study of the charged-current and neutral-current nuclear responses to supernova neutrinos for 136Xe . Method: The cross sections are computed by using the well-established framework for studies of semileptonic processes in nuclei introduced by O'Connell, Donnelly, and Walecka [Phys. Rev. C 6, 719 (1972), 10.1103/PhysRevC.6.719]. The nuclear wave functions of the initial and the final nuclear states for the neutral-current neutrino-nucleus scattering in 136Xe are computed by using the quasiparticle random-phase approximation (QRPA). Similarly, the pnQRPA is adopted to construct the initial and final nuclear states which are relevant for the charged-current reactions. The nuclear responses to supernova neutrinos are subsequently computed by folding the cross sections with appropriate energy spectra for the incoming neutrinos. Results: We present results for the cross sections of the charged-current and neutral-current neutrino and antineutrino scatterings off 136Xe . Nuclear responses to supernova neutrinos are also given. For the considered scenario for the neutrino mixing we have found that neutrino interactions with matter and so-called collective neutrino oscillations enhance significantly the neutrino and antineutrino flux-averaged cross sections. Conclusions: We have found that for the charged-current and neutral-current neutrino scatterings off 136Xe transitions mediated by the 1+ multipole are the most important ones. However, for the charged

  6. Constraining the Astrophysical S Factor of the 3He(α,γ)7Be Reaction

    NASA Astrophysics Data System (ADS)

    Carmona-Gallardo, M.; Rojas, A.; Nara Singh, B. S.; Akers, C.; Aviv, O.; Borge, M. J. G.; Christian, G.; Davids, B.; Fallis, J.; Fulton, B. R.; Hager, U.; Haquin, G.; Hass, M.; Hutcheon, D. A.; Nir-El, Y.; Ottewell, D.; Ruiz, C.; Sjue, S. K. L.; Tengblad, O.; Yaniv, R.; Yungreis, Z.

    The cross section of the 3He(α,γ)7Be reaction has been widely studied both from the theoretical and the experimental fronts due to its relevance to the standard solar model and to the Big Bang Nucleosynthesis calculations. We report here on cross section measurements in the energy region Ec.m. = 1-3 MeV using the direct recoil counting method in an attempt to resolve the discrepancies among the previous data sets and calculations in this energy region and thus to constrain the extrapolations of the S34(E) curve to astrophysical energies.

  7. Neutrinos: Theory and Phenomenology

    SciTech Connect

    Parke, Stephen

    2013-10-22

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

  8. Overview and Status of Experimental Neutrino Physics

    NASA Astrophysics Data System (ADS)

    Stancu, Ion

    2002-10-01

    Seventy years after the existence of the neutrino has been postulated by Wolfgang Pauli, these elusive particles remain surrounded by mystery. One of the most fundamental questions about neutrinos is whether they have an identically vanishing mass, as assumed by the Standard Model, or not. Direct measurements have proven to be extremely difficult to perform, and have yielded so far only upper limits. However, if neutrino flavour oscillations do happen, this would automatically imply that at least one of the three neutrinos (the electron, muon or tau neutrino) must have a non-zero mass. The present experimental data indicate that both the solar and atmospheric neutrino deficits can be explained by the phenomenon of neutrino oscillations, while the positive signal reported by the accelerator-based LSND experiment remains to be verified by an independent measurement (MiniBooNE). This talk reviews the current status of the neutrino oscillations experiments, experiments which are quite likely to produce results with significant consequences for both the Standard Model and Cosmology.

  9. Dark matter vs. neutrinos: the effect of astrophysical uncertainties and timing information on the neutrino floor

    SciTech Connect

    Davis, Jonathan H.

    2015-03-09

    Future multi-tonne Direct Detection experiments will be sensitive to solar neutrino induced nuclear recoils which form an irreducible background to light Dark Matter searches. Indeed for masses around 6 GeV the spectra of neutrinos and Dark Matter are so similar that experiments are said to run into a neutrino floor, for which sensitivity increases only marginally with exposure past a certain cross section. In this work we show that this floor can be overcome using the different annual modulation expected from solar neutrinos and Dark Matter. Specifically for cross sections below the neutrino floor the DM signal is observable through a phase shift and a smaller amplitude for the time-dependent event rate. This allows the exclusion power to be improved by up to an order of magnitude for large exposures. In addition we demonstrate that, using only spectral information, the neutrino floor exists over a wider mass range than has been previously shown, since the large uncertainties in the Dark Matter velocity distribution make the signal spectrum harder to distinguish from the neutrino background. However for most velocity distributions it can still be surpassed using timing information, and so the neutrino floor is not an absolute limit on the sensitivity of Direct Detection experiments.

  10. Dark matter vs. neutrinos: the effect of astrophysical uncertainties and timing information on the neutrino floor

    SciTech Connect

    Davis, Jonathan H.

    2015-03-01

    Future multi-tonne Direct Detection experiments will be sensitive to solar neutrino induced nuclear recoils which form an irreducible background to light Dark Matter searches. Indeed for masses around 6 GeV the spectra of neutrinos and Dark Matter are so similar that experiments are said to run into a neutrino floor, for which sensitivity increases only marginally with exposure past a certain cross section. In this work we show that this floor can be overcome using the different annual modulation expected from solar neutrinos and Dark Matter. Specifically for cross sections below the neutrino floor the DM signal is observable through a phase shift and a smaller amplitude for the time-dependent event rate. This allows the exclusion power to be improved by up to an order of magnitude for large exposures. In addition we demonstrate that, using only spectral information, the neutrino floor exists over a wider mass range than has been previously shown, since the large uncertainties in the Dark Matter velocity distribution make the signal spectrum harder to distinguish from the neutrino background. However for most velocity distributions it can still be surpassed using timing information, and so the neutrino floor is not an absolute limit on the sensitivity of Direct Detection experiments.

  11. Neutrino oscillations as a probe of dark energy.

    PubMed

    Kaplan, David B; Nelson, Ann E; Weiner, Neal

    2004-08-27

    We consider a class of theories in which neutrino masses depend significantly on environment, as a result of interactions with the dark sector. Such theories of mass varying neutrinos were recently introduced to explain the origin of the cosmological dark energy density and why its magnitude is apparently coincidental with that of neutrino mass splittings. In this Letter we argue that in such theories neutrinos can exhibit different masses in matter and in vacuum, dramatically affecting neutrino oscillations. As an example of modifications to the standard picture, we consider simple models that may simultaneously account for the LSND anomaly, KamLAND, K2K, and studies of solar and atmospheric neutrinos, while providing motivation to continue to search for neutrino oscillations in short baseline experiments such as BooNE.

  12. The Intermediate Neutrino Program

    SciTech Connect

    Adams, C.; et al.

    2015-03-23

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

  13. Limits on neutrino radiative decay from SN1987A

    SciTech Connect

    Jaffe, A.H.; Fenimore, E.; Turner, M.S.

    1993-01-01

    The authors calculate limits on the properties of neutrinos using data from gamma ray detectors on the Pioneer Venus Orbiter and Solar Max Mission satellites. A massive neutrino decaying in flight from the supernova would produce gamma rays detectable by these instruments. The lack of such a signal allows us to constrain the mass, radiative lifetime, and branching ratio to photons of a massive neutrino species produced in the supernova.

  14. Limits on neutrino radiative decay from SN1987A

    NASA Technical Reports Server (NTRS)

    Jaffe, Andrew H.; Fenimore, ED; Turner, Michael S.

    1993-01-01

    We calculate limits on the properties of neutrinos using data from gamma ray detectors on the Pioneer Venus Orbiter and Solar Max Mission satellites. A massive neutrino decaying in flight from the supernova would produce gamma rays detectable by these instruments. The lack of such a signal allows us to constrain the mass, radiative lifetime, and branching ratio to photons of a massive neutrino species produced in the supernova.

  15. A BAYESIAN ASSESSMENT OF P-VALUES FOR SIGNIFICANCE ESTIMATION OF POWER SPECTRA AND AN ALTERNATIVE PROCEDURE, WITH APPLICATION TO SOLAR NEUTRINO DATA

    SciTech Connect

    Sturrock, P. A.; Scargle, J. D.

    2009-11-20

    the corresponding post-probability and hence the corresponding log-odds. It seems sensible-even if not logically essential-to seek a likelihood function for which the two procedures lead to the same answer. We find that this consistency condition may be satisfied, to good approximation, by a special case of the previously proposed likelihood function. We find that the resulting significance estimates are considerably more conservative than those usually associated with the p-values. As two examples, we apply the new procedure to two recent analyses of solar neutrino data: (1) power spectrum analysis of Super-Kamiokande data and (2) the combined analysis of radiochemical neutrino data and irradiance data.

  16. Neutrino in Cosmology

    NASA Astrophysics Data System (ADS)

    Kirilova, D.

    2010-09-01

    The relic neutrinos from the Big Bang or the Cosmic Neutrino Background (CNB) neutrinos are expected to be the most abundant particles in our universe after the relic photons of the Cosmic Microwave Background (CMB). They carry precious information from the early epoch when our universe was only 1 sec old. Although not yet directly detected, CNB may be revealed indirectly through cosmological observations due to their important cosmological influence. I review the cosmological role of neutrinos and the present cosmological constraints on neutrino characteristics. Namely, I discuss the impact of neutrinos in the cosmic expansion, neutrino decoupling, the role of neutrinos in the primordial production of light elements, their effect on CMB anisotropies, LSS formation, the possible neutrino contribution to the Dark Matter in the universe, leptogenesis, etc. Due to the considerable cosmological influence of neutrinos, cosmological bounds on neutrino properties from observational data exist. I review the cosmological constraints on the neutrino characteristics, such as the effective number of neutrino species, neutrino mass and mixing parameters, lepton number of the universe, gravitational clustering of neutrinos, presence of sterile neutrino, etc.

  17. Neutrinos in Nuclear Physics

    SciTech Connect

    McKeown, Bob

    2015-06-01

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

  18. Neutrino-Argon Interaction with GENIE Event Generator

    NASA Astrophysics Data System (ADS)

    Chesneanu, Daniela

    2010-11-01

    Neutrinos are very special particles, have only weak interactions, except gravity, and are produced in very different processes in Nuclear and Particle Physics. Neutrinos are, also, messengers from astrophysical objects, as well as relics from Early Universe. Therefore, its can give us information on processes happening in the Universe, during its evolution, which cannot be studied otherwise. The underground instrumentation including a variety of large and very large detectors, thanks to technical breakthroughs, have achieved new fundamental results like the solution of the solar neutrino puzzle and the evidence for Physics beyond the Standard Model of elementary interactions in the neutrino sector with non-vanishing neutrino masses and lepton flavour violation. Two of the LAGUNA (Large Apparatus studying Grand Unification and Neutrino Astrophysics) detectors, namely: GLACIER (Giant Liquid Argon Charge Imaging ExpeRiment) [1] and LENA (Low Energy Neutrino Astrophysics) [2] could be emplaced in ``Unirea'' salt mine from Slănic-Prahova, Romania. A detailed analysis of the conditions and advantages is necessary. A few results have been presented previously [3]. In the present work, we propose to generate events and compute the cross sections for interactions between neutrino and Argon-40, to estimate possible detection performances and event types. For doing this, we use the code GENIE (G_enerates E_vents for N_eutrino I_nteraction E_xperiments) [4]. GENIE Code is an Object-Oriented Neutrino MC Generator supported and developed by an international collaboration of neutrino interaction experts.

  19. Relic Neutrino Absorption Spectroscopy

    SciTech Connect

    Eberle, b

    2004-01-28

    Resonant annihilation of extremely high-energy cosmic neutrinos on big-bang relic anti-neutrinos (and vice versa) into Z-bosons leads to sizable absorption dips in the neutrino flux to be observed at Earth. The high-energy edges of these dips are fixed, via the resonance energies, by the neutrino masses alone. Their depths are determined by the cosmic neutrino background density, by the cosmological parameters determining the expansion rate of the universe, and by the large redshift history of the cosmic neutrino sources. We investigate the possibility of determining the existence of the cosmic neutrino background within the next decade from a measurement of these absorption dips in the neutrino flux. As a by-product, we study the prospects to infer the absolute neutrino mass scale. We find that, with the presently planned neutrino detectors (ANITA, Auger, EUSO, OWL, RICE, and SalSA) operating in the relevant energy regime above 10{sup 21} eV, relic neutrino absorption spectroscopy becomes a realistic possibility. It requires, however, the existence of extremely powerful neutrino sources, which should be opaque to nucleons and high-energy photons to evade present constraints. Furthermore, the neutrino mass spectrum must be quasi-degenerate to optimize the dip, which implies m{sub {nu}} 0.1 eV for the lightest neutrino. With a second generation of neutrino detectors, these demanding requirements can be relaxed considerably.

  20. Short distance neutrino oscillations with Borexino

    NASA Astrophysics Data System (ADS)

    Caminata, A.; Agostini, M.; Altenmüller, K.; Appel, S.; Bellini, G.; Benziger, J.; Berton, N.; Bick, D.; Bonfini, G.; Bravo, D.; Caccianiga, B.; Calaprice, F.; Cavalcante, P.; Chepurnov, A.; Cribier, M.; D'Angelo, D.; Davini, S.; Derbin, A.; di Noto, L.; Durero, M.; Empl, A.; Etenko, A.; Farinon, S.; Fischer, V.; Fomenko, K.; Franco, D.; Gabriele, F.; Gaffiot, J.; Galbiati, C.; Ghiano, C.; Giammarchi, M.; Göger-Neff, M.; Goretti, A.; Gromov, M.; Hagner, C.; Houdy, Th.; Hungerford, E.; Ianni, Aldo; Ianni, Andrea; Jonquères, N.; Kaiser, M.; Kobychev, V.; Korablev, D.; Korga, G.; Kryn, D.; Lachenmaier, T.; Lasserre, T.; Laubenstein, M.; Lehnert, B.; Link, J.; Litvinovich, E.; Lombardi, F.; Lombardi, P.; Ludhova, L.; Lukyanchenko, G.; Machulin, I.; Maneschg, W.; Marcocci, S.; Maricic, J.; Mention, G.; Meroni, E.; Meyer, M.; Miramonti, L.; Misiaszek, M.; Montuschi, M.; Muratova, V.; Musenich, R.; Neumair, B.; Oberauer, L.; Obolensky, M.; Ortica, F.; Pallavicini, M.; Papp, L.; Perasso, L.; Pocar, A.; Ranucci, G.; Razeto, A.; Re, A.; Romani, A.; Rossi, N.; Schönert, S.; Scola, L.; Simgen, H.; Skorokhvatov, M.; Smirnov, O.; Sotnikov, A.; Sukhotin, S.; Suvorov, Y.; Tartaglia, R.; Testera, G.; Veyssière, C.; Vivier, M.; Vogelaar, R. B.; von Feilitzsch, F.; Wang, H.; Winter, J.; Wojcik, M.; Wurm, M.; Zaimidoroga, O.; Zavatarelli, S.; Zuber, K.; Zuzel, G.

    2016-07-01

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

  1. Neutrino-flavoured sneutrino dark matter

    NASA Astrophysics Data System (ADS)

    March-Russell, John; McCabe, Christopher; McCullough, Matthew

    2010-03-01

    A simple theory of supersymmetric dark matter (DM) naturally linked to neutrino flavour physics is studied. The DM sector comprises a spectrum of mixed lhd-rhd sneutrino states where both the sneutrino flavour structure and mass splittings are determined by the associated neutrino masses and mixings. Prospects for indirect detection from solar capture are good due to a large sneutrino-nucleon cross-section afforded by the inelastic splitting (solar capture limits exclude an explanation of DAMA/LIBRA). We find parameter regions where all heavier states will have decayed, leaving only one flavour mixture of sneutrino as the candidate DM. Such regions have a unique ‘smoking gun’ signature — sneutrino annihilation in the Sun produces a pair of neutrino mass eigenstates free from vacuum oscillations, with the potential for detection at neutrino telescopes through the observation of a hard spectrum of ν μ and ν τ (for a normal neutrino hierarchy). Next generation direct detection experiments can explore much of the parameter space through both elastic and inelastic scattering. We show in detail that the observed neutrino masses and mixings can arise as a consequence of supersymmetry breaking effects in the sneutrino DM sector, consistent with all experimental constraints.

  2. New neutrino mass sum rule from the inverse seesaw mechanism

    NASA Astrophysics Data System (ADS)

    Dorame, L.; Morisi, S.; Peinado, E.; Valle, J. W. F.; Rojas, Alma D.

    2012-09-01

    A class of discrete flavor-symmetry-based models predicts constrained neutrino mass matrix schemes that lead to specific neutrino mass sum rules. One of these implies a lower bound on the effective neutrinoless double beta mass parameter, even for normal hierarchy neutrinos. Here we propose a new model based on the S4 flavor symmetry that leads to the new neutrino mass sum rule and discuss how to generate a nonzero value for the reactor angle θ13 indicated by recent experiments, and the resulting correlation with the solar angle θ12.

  3. Neutrino Oscillations with Three Active and Three Sterile Neutrinos

    NASA Astrophysics Data System (ADS)

    Kisslinger, Leonard S.

    2016-07-01

    This is an extension of estimates of the probability of μ to e neutrino oscillation with one sterile neutrino to three sterile neutrinos, using a 6x6 matrix. Since the mixing angle for only one sterile neutrino has been experimentally determined, we estimate the μ to e neutrino oscillation probability with different mixing angles for two of the sterile neutrinos.

  4. Implications of solar wind measurements for solar models and composition

    NASA Astrophysics Data System (ADS)

    Serenelli, Aldo; Scott, Pat; Villante, Francesco L.; Vincent, Aaron C.; Asplund, Martin; Basu, Sarbani; Grevesse, Nicolas; Peña-Garay, Carlos

    2016-08-01

    We critically examine recent claims of a high solar metallicity by von Steiger & Zurbuchen (2016, vSZ16) based on in situ measurements of the solar wind, rather than the standard spectroscopically-inferred abundances (Asplund et al. 2009, AGSS09). We test the claim by Vagnozzi et al. (2016) that a composition based on the solar wind enables one to construct a standard solar model in agreement with helioseismological observations and thus solve the decades-old solar modelling problem. We show that, although some helioseismological observables are improved compared to models computed with spectroscopic abundances, most are in fact worse. The high abundance of refractory elements leads to an overproduction of neutrinos, with a predicted 8B flux that is nearly twice its observed value, and 7Be and CNO fluxes that are experimentally ruled out at high confidence. A combined likelihood analysis shows that models using the vSZ16 abundances fare worse than AGSS09 despite a higher metallicity. We also present astrophysical and spectroscopic arguments showing the vSZ16 composition to be an implausible representation of the solar interior, identifying the first ionisation potential effect in the outer solar atmosphere and wind as the likely culprit.

  5. Implications of solar wind measurements for solar models and composition

    NASA Astrophysics Data System (ADS)

    Serenelli, Aldo; Scott, Pat; Villante, Francesco L.; Vincent, Aaron C.; Asplund, Martin; Basu, Sarbani; Grevesse, Nicolas; Peña-Garay, Carlos

    2016-11-01

    We critically examine recent claims of a high solar metallicity by von Steiger & Zurbuchen (2016, vSZ16) based on in situ measurements of the solar wind, rather than the standard spectroscopically inferred abundances (Asplund et al. 2009, hereafter AGSS09). We test the claim by Vagnozzi et al. (2016) that a composition based on the solar wind enables one to construct a standard solar model in agreement with helioseismological observations and thus solve the decades-old solar modelling problem. We show that, although some helioseismological observables are improved compared to models computed with spectroscopic abundances, most are in fact worse. The high abundance of refractory elements leads to an overproduction of neutrinos, with a predicted 8B flux that is nearly twice its observed value, and 7Be and CNO fluxes that are experimentally ruled out at high confidence. A combined likelihood analysis shows that models using the vSZ16 abundances are worse than AGSS09 despite a higher metallicity. We also present astrophysical and spectroscopic arguments showing the vSZ16 composition to be an implausible representation of the solar interior, identifying the first ionization potential effect in the outer solar atmosphere and wind as the likely culprit.

  6. Astrophysics and cosmology closing in on neutrino masses

    NASA Technical Reports Server (NTRS)

    Dar, Arnon

    1990-01-01

    Massive neutrinos are expected in most grand unified theories that attempt to unify the strong and electroweak interactions. So far, heroic laboratory experiments have yielded only upper bounds on the masses of the elusive neutrinos. These bounds, however, are not very restrictive and cannot even exclude the possibility that the dark matter in the universe consists of neutrinos. The astrophysical and cosmological bounds on the masses of the muon and tau neutrinos, m(nu sub mu) and m(nu sub tau), which already are much more restrictive than the laboratory bounds, and the laboratory bound on the mass of the electron neutrino, m(nu sub e) can be improved significantly by future astrophysical and cosmological observations that perhaps will pin down the neutrino masses. Indeed, the recent results from the solar neutrino experiments combined with the seesaw mechanism for generating neutrino masses suggest that m(nu sub e) of about 10 to the -8th electron volts, m(nu sub mu) of about 0.001 electron volts, and m(nu sub tau) of about 10 electron volts, which can be tested in the near future by solar neutrino and accelerator experiments.

  7. Neutral-current detectors for the Sudbury Neutrino Observatory

    SciTech Connect

    Hime, A.; SNO Collaboration

    1997-09-01

    With its heavy water target, the Sudbury Neutrino Observatory has the unique opportunity to measure both the {sup 8}B flux of electron neutrinos from the Sun and the flux of all active neutrino species independently, thus offering a direct and model-independent test of a neutrino oscillation solution to the solar neutrino problem. The authors report on the physics intent and design of a discrete method of neutral-current detection in the Sudbury neutrino observatory that will utilize ultra-low background {sup 3}He proportional counters dispersed throughout the heavy water volume. Projections of background in all components of the detector are considered in an analysis of the ability to extract the neutral-current signal and the neutral-current to charged-current ratio.

  8. Experimental Neutrino Physics: Final Report

    SciTech Connect

    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.

  9. Neutrino Physics at Fermilab

    ScienceCinema

    Saoulidou, Niki

    2016-07-12

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

  10. Neutrino Nucleosynthesis in Supernovae

    SciTech Connect

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

    2009-05-04

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

  11. Neutrino-driven Explosion of a 20 Solar-mass Star in Three Dimensions Enabled by Strange-quark Contributions to Neutrino–Nucleon Scattering

    NASA Astrophysics Data System (ADS)

    Melson, Tobias; Janka, Hans-Thomas; Bollig, Robert; Hanke, Florian; Marek, Andreas; Müller, Bernhard

    2015-08-01

    Interactions with neutrons and protons play a crucial role for the neutrino opacity of matter in the supernova core. Their current implementation in many simulation codes, however, is rather schematic and ignores not only modifications for the correlated nuclear medium of the nascent neutron star, but also free-space corrections from nucleon recoil, weak magnetism, or strange quarks, which can easily add up to changes of several 10% for neutrino energies in the spectral peak. In the Garching supernova simulations with the Prometheus-Vertex code, such sophistications have been included for a long time except for the strange-quark contributions to the nucleon spin, which affect neutral-current neutrino scattering. We demonstrate on the basis of a 20 {M}ȯ progenitor star that a moderate strangeness-dependent contribution of {g}{{a}}{{s}}=-0.2 to the axial-vector coupling constant {g}{{a}}≈ 1.26 can turn an unsuccessful three-dimensional (3D) model into a successful explosion. Such a modification is in the direction of current experimental results and reduces the neutral-current scattering opacity of neutrons, which dominate in the medium around and above the neutrinosphere. This leads to increased luminosities and mean energies of all neutrino species and strengthens the neutrino-energy deposition in the heating layer. Higher nonradial kinetic energy in the gain layer signals enhanced buoyancy activity that enables the onset of the explosion at ˜300 ms after bounce, in contrast to the model with vanishing strangeness contributions to neutrino–nucleon scattering. Our results demonstrate the close proximity to explosion of the previously published, unsuccessful 3D models of the Garching group.

  12. Neutrino-Argon Interaction with GENIE Event Generator

    SciTech Connect

    Chesneanu, Daniela

    2010-11-24

    Neutrinos are very special particles, have only weak interactions, except gravity, and are produced in very different processes in Nuclear and Particle Physics. Neutrinos are, also, messengers from astrophysical objects, as well as relics from Early Universe. Therefore, its can give us information on processes happening in the Universe, during its evolution, which cannot be studied otherwise. The underground instrumentation including a variety of large and very large detectors, thanks to technical breakthroughs, have achieved new fundamental results like the solution of the solar neutrino puzzle and the evidence for Physics beyond the Standard Model of elementary interactions in the neutrino sector with non-vanishing neutrino masses and lepton flavour violation.Two of the LAGUNA(Large Apparatus studying Grand Unification and Neutrino Astrophysics) detectors, namely: GLACIER (Giant Liquid Argon Charge Imaging ExpeRiment) and LENA (Low Energy Neutrino Astrophysics) could be emplaced in 'Unirea' salt mine from Slanic-Prahova, Romania. A detailed analysis of the conditions and advantages is necessary. A few results have been presented previously. In the present work, we propose to generate events and compute the cross sections for interactions between neutrino and Argon-40, to estimate possible detection performances and event types. For doing this, we use the code GENIE(G lowbar enerates E lowbar vents for N lowbar eutrino I lowbar nteraction E lowbar xperiments). GENIE Code is an Object-Oriented Neutrino MC Generator supported and developed by an international collaboration of neutrino interaction experts.

  13. The Final Results from the Sudbury Neutrino Observatory

    ScienceCinema

    None

    2016-07-12

    The Sudbury Neutrino Observatory (SNO) was a water Cherenkov detector dedicated to investigate elementary particles called neutrinos. It successfully took data between 1999 and 2006. The detector was unique in its use of heavy water as a detection medium, permitting it to make a solar model-independent test of solar neutrino mixing. In fact, SNO conclusively showed that solar neutrinos oscillate on their way from the core of the Sun to the Earth. This groundbreaking observation was made during three independent phases of the experiment. Even if data taking ended, SNO is still in a mode of precise determination of the solar neutrino oscillation parameters because all along SNO had developed several methods to tell charged-current events apart from neutral-current events. This ability is crucial for the final and ultimate data analysis of all the phases. The physics reach of a combined three-phase solar analysis will be reviewed together with results and subtleties about solar neutrino physics.

  14. KamLAND's precision neutrino oscillation measurements

    NASA Astrophysics Data System (ADS)

    Decowski, M. P.

    2016-07-01

    The KamLAND experiment started operation in the Spring of 2002 and is operational to this day. The experiment observes signals from electron antineutrinos from distant nuclear reactors. The program, spanning more than a decade, allowed the determination of LMA-MSW as the solution to the solar neutrino transformation results (under the assumption of CPT invariance) and the measurement of various neutrino oscillation parameters. In particular, the solar mass-splitting Δ m212 was determined to high precision. Besides the study of neutrino oscillation, KamLAND started the investigation of geologically produced antineutrinos (geo-ν‾e). The collaboration also reported on a variety of other topics related to particle and astroparticle physics.

  15. Searches for high frequency variations in the 8-B neutrino flux at the Sudbury neutrino observatory

    SciTech Connect

    Rielage, Keith; Seibert, Stanley R; Hime, Andrew; Elliott, Steven R; Stonehill, L C; Wouters, J M; Aharmim, B; Ahmed, S N; Anthony, A E; Barros, N; Beier, E W; Bellerive, A; Belttran, B; Bergevin, M; Biller, S D; Boudjemline, K; Burritt, T H; Cai, B; Chan, Y D; Chauhan, D; Chen, M; Cleveland, B T; Cox - Mobrand, G A; Dai, X; Deng, H; Detwiler, J; Dimarco, M; Doe, P J; Drouin, P - L; Duba, C A; Duncan, F A; Dunford, M; Earle, E D; Evans, H C; Ewan, G T; Farine, J; Fergani, H; Fleurot, F; Ford, R J; Formaggilo, J A; Gagnon, N; Goon, J Tm; Guillian, E; Habib, S; Hahn, R L; Hallin, A L; Hallman, E D; Harvey, P J; Hazama, R; Heintzelman, W J; Heise, J; Helmer, R L; Howard, C; Howe, M A; Huang, M; Jamieson, B; Jelley, N A; Keeter, K J; Klein, J R; Kos, M; Kraus, C; Krauss, C B; Kutter, T; Kyba, C C M; Law, J; Lawson, I T; Lesko, K T; Leslie, J R; Loach, J C; Maclellan, R; Majerus, S; Mak, H B; Maneira, J; Martin, R; Mccauley, N; Mc Donald, A B; Mcgee, S; Miffin, C; Miller, M L; Monreal, B; Monroe, J; Morissette, B; Nickel, B G; Noble, A J; O' Keeffe, H M; Oblath, N S; Orebi Gann, G D; Oser, S M; Ott, R A; Peeters, S J M; Poon, A W P; Prior, G; Reitzner, S D; Robertson, B C; Robertson, R G H; Rollin, E; Schwendener, M H; Secrest, J A; Seibert, S R; Simard, O; Sinclair, D; Sinclair, L; Skensved, P; Sonley, T J; Tesic, G; Tolich, N; Tsui, T; Tunnell, C D; Van Berg, R; Van Devender, B A; Virtue, C J; Wall, B L; Waller, D; Wan Chan Tseung, H; West, N; Wilkerson, J F; Wilson, J R; Wright, A; Yeh, M; Zhang, F; Zuber, K

    2009-01-01

    We have peformed three searches for high-frequency signals in the solar neutrino flux measured by the Sudbury Neutrino Observatory (SNO), motivated by the possibility that solar g-mode oscillations could affect the production or propagation of solar {sup 8}B neutrinos. The first search looked for any significant peak in the frequency range l/day to 144/day, with a sensitivity to sinusoidal signals with amplitudes of 12% or greater. The second search focused on regions in which g-mode signals have been claimed by experiments aboard the SoHO satellite, and was sensitive to signals with amplitudes of 10% or greater. The third search looked for extra power across the entire frequency band. No statistically significant signal was detected in any of the three searches.

  16. QLC relation and neutrino mass hierarchy

    SciTech Connect

    Ferrandis, Javier; Pakvasa, Sandip

    2005-01-27

    Latest measurements have revealed that the deviation from a maximal solar mixing angle is approximately the Cabibbo angle, i.e., QLC relation. We argue that it is not plausible that this deviation from maximality, be it a coincidence or not, comes from the charged lepton mixing. Consequently we have calculated the required corrections to the exactly bimaximal neutrino mass matrix ansatz necessary to account for the solar mass difference and the solar mixing angle. We point out that the relative size of these two corrections depends strongly on the hierarchy case under consideration. We find that the inverted hierarchy case with opposite CP parities, which is known to guarantee the RGE stability of the solar mixing angle, offers the most plausible scenario for a high energy origin of a QLC-corrected bimaximal neutrino mass matrix. This possibility may allow us to explain the QLC relation in connection with the origin of the charged fermion mass matrices.

  17. Supernova neutrino detection

    SciTech Connect

    Scholberg, K.

    2015-07-15

    In this presentation I summarize the main detection channels for neutrinos from core-collapse supernovae, and describe current status of and future prospects for supernova-neutrino-sensitive detectors worldwide.

  18. Geo-neutrino Observation

    SciTech Connect

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

    2009-12-17

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

  19. Neutrino Oscillation Physics

    SciTech Connect

    Kayser, Boris

    2012-06-01

    To complement the neutrino-physics lectures given at the 2011 International School on Astro Particle Physics devoted to Neutrino Physics and Astrophysics (ISAPP 2011; Varenna, Italy), at the 2011 European School of High Energy Physics (ESHEP 2011; Cheila Gradistei, Romania), and, in modified form, at other summer schools, we present here a written description of the physics of neutrino oscillation. This description is centered on a new way of deriving the oscillation probability. We also provide a brief guide to references relevant to topics other than neutrino oscillation that were covered in the lectures. Neutrinos and photons are by far the most abundant elementary particles in the universe. Thus, if we would like to comprehend the universe, we must understand the neutrinos. Of course, studying the neutrinos is challenging, since the only known forces through which these electrically-neutral leptons interact are the weak force and gravity. Consequently, interactions of neutrinos in a detector are very rare events, so that very large detectors and intense neutrino sources are needed to make experiments feasible. Nevertheless, we have confirmed that the weak interactions of neutrinos are correctly described by the Standard Model (SM) of elementary particle physics. Moreover, in the last 14 years, we have discovered that neutrinos have nonzero masses, and that leptons mix. These discoveries have been based on the observation that neutrinos can change from one 'flavor' to another - the phenomenon known as neutrino oscillation. We shall explain the physics of neutrino oscillation, deriving the probability of oscillation in a new way. We shall also provide a very brief guide to references that can be used to study some major neutrino-physics topics other than neutrino oscillation.

  20. Speedy neutrinos, again

    NASA Astrophysics Data System (ADS)

    Goodman, Frank

    2012-02-01

    I am writing with regard to the OPERA collaboration's recent publicizing of experimental results suggesting that neutrinos have been observed travelling faster than light (see "Superluminal neutrinos split OPERA collaboration", November 2011 pp12-13 "The brave new-media world", ibid p19; and "Speedy neutrinos", December 2011 pp20-21).

  1. Neutrinos in the early universe

    NASA Astrophysics Data System (ADS)

    Kirilova, D.; Frere, J.-M.

    2012-12-01

    The neutrinos from the Big Bang or the Cosmic Neutrino Background (CNB) carry precious information from the early epoch when our universe was only 1 s old. Although not yet directly detected, CNB may be revealed indirectly through cosmological observations due to neutrino important cosmological influence. We review the cosmological role of neutrinos and the cosmological constraints on neutrino characteristics. Namely, we discuss the impact of neutrinos in the early universe: the cosmic expansion, neutrino decoupling, the role of neutrinos in the primordial production of light elements, leptogenesis, etc. We briefly discuss the role of neutrino at later stages of the universe. Due to the considerable cosmological influence of neutrinos, cosmological bounds on neutrino properties from observational data exist. We review the cosmological constraints on the effective number of neutrino species, neutrino mass and mixing parameters, lepton number of the universe, presence of sterile neutrino, etc.

  2. Detecting Cosmic Neutrinos with IceCube at the Earth's South Pole

    NASA Astrophysics Data System (ADS)

    Kurahashi Neilson, Naoko

    2016-01-01

    The universe has been studied using light since the dawn of astronomy, when starlight captured the human eye. The IceCube Neutrino Observatory views the universe in a different and unique way: in high-energy neutrinos. IceCube's recent discovery of a diffuse flux of astrophysical neutrinos, in other words, the universe glowing in neutrinos from beyond the solar system, started a new era of neutrino astronomy. I will motivate why neutrinos are a necessary messenger in high-energy astronomy. I will discuss the multiple diffuse flux analyses in IceCube that observe the astrophysical flux, and what each can tell us. Spatial analyses that aim to identify the sources of such astrophysical neutrinos will also be discussed, followed by an attempt to reconcile all results, to draw a coherent picture that is the state of neutrino astronomy.

  3. SNO: solving the mystery of the missing neutrinos

    SciTech Connect

    Jelley, Nick; Poon, Alan

    2007-03-30

    The end of an era came on 28 November 2006 when the Sudbury Neutrino Observatory (SNO) finally stopped data-taking after eight exciting years of discoveries. During this time the Observatory saw evidence that neutrinos, produced in the fusion of hydrogen in the solar core, change flavour while passing through the Sun on their way to the Earth. This observation explained the longstanding puzzle as to why previous experiments had seen fewer solar neutrinos than predicted and confirmed that these elusive particles have mass. Solar neutrinos were first detected in Ray Davis's radiochemical experiment in 1967, for which discovery he shared the 2002 Nobel Prize in Physics. Surprisingly he found only about a third of the number predicted from models of the Sun's output. This deficit, the so-called Solar Neutrino Problem, was confirmed by Kamiokande-II while other experiments saw related deficits of solar neutrinos. A possible explanation for this deficit, suggested by Gribov and Pontecorvo in 1969, was that some of the electron-type neutrinos, which are produced in the Sun, had ''oscillated'' into neutrinos that could not be detected in the Davis detector. The oscillation mechanism requires that neutrinos have non-zero mass. The unique advantage, which was pointed out by the late Herb Chen in 1985, of using heavy water (D{sub 2}O) to detect the neutrinos from {sup 8}B decays in the solar fusion process is that it enables both the number of electron-type and of all types of neutrinos to be measured. A comparison of the flux of electron-type neutrinos to that of all flavours could then reveal whether flavour transformation is the cause of the solar neutrino deficit. In heavy water neutrinos of all types can break a deuteron apart into its constituent proton and neutron (neutral-current reaction), while only electron-type neutrinos can change the deuteron into two protons and release an electron (charged-current reaction). SNO was designed by scientists from Canada, the USA

  4. Mass determination of neutrinos

    NASA Technical Reports Server (NTRS)

    Chiu, Hong-Yee

    1988-01-01

    A time-energy correlation method has been developed to determine the signature of a nonzero neutrino mass in a small sample of neutrinos detected from a distant source. The method is applied to the Kamiokande II (Hirata et al., 1987) and IMB (Bionta et al., 1987) observations of neutrino bursts from SN 1987A. Using the Kamiokande II data, the neutrino rest mass is estimated at 2.8 + 2.0, - 1.4 eV and the initial neutrino pulse is found to be less than 0.3 sec full width, followed by an emission tail lasting at least 10 sec.

  5. Neutrinos from AGN

    NASA Technical Reports Server (NTRS)

    Kazanas, Demosthenes; White, Nicholas E. (Technical Monitor)

    2000-01-01

    The great penetrating power of neutrinos makes them ideal probe of astrophysical sites and conditions inaccessible to other forms of radiation. These are the centers of stars (collapsing or not) and the centers of Active Galactic Nuclei (AGN). It has been suggested that AGN presented a very promising source of high energy neutrinos, possibly detectable by underwater neutrino detectors. This paper reviews the evolution of ideas concerning the emission of neutrinos from AGN in view of the more recent developments in gamma-ray astronomy and their implications for the neutrino emission from these class of objects.

  6. Sneutrino-antisneutrino mixing and neutrino mass in anomaly-mediated supersymmetry breaking scenario.

    PubMed

    Choi, Kiwoon; Hwang, Kyuwan; Song, Wan Young

    2002-04-01

    In supersymmetric models with nonzero Majorana neutrino mass, the sneutrino and antisneutrino mix, which may lead to same-sign dilepton signals in future collider experiments. We point out that the anomaly-mediated supersymmetry breaking scenario has a good potential to provide an observable rate of such signals for the neutrino masses suggested by the atmospheric and solar neutrino oscillations. It is noted also that the sneutrino-antisneutrino mixing can provide much stronger information on some combinations of the neutrino masses and mixing angles than the neutrino experiments.

  7. Atmospheric Neutrinos: Background and Signal

    SciTech Connect

    Mocioiu, Irina

    2010-11-24

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

  8. Collective neutrino oscillations in supernovae

    SciTech Connect

    Duan, Huaiyu

    2014-06-24

    In a dense neutrino medium neutrinos can experience collective flavor transformation through the neutrino-neutrino forward scattering. In this talk we present some basic features of collective neutrino flavor transformation in the context in core-collapse supernovae. We also give some qualitative arguments for why and when this interesting phenomenon may occur and how it may affect supernova nucleosynthesis.

  9. Possible scenario for MaVaN's as the only neutrino flavor conversion mechanism in the Sun

    SciTech Connect

    Holanda, P.C. de

    2009-07-01

    Mass Varying neutrino mechanisms were proposed to link the neutrino mass scale with dark energy, addressing the coincidence problem. In some scenarios this mass can present a dependence on the baryonic density felt by neutrinos, creating an effective neutrino mass that depends both on the neutrino and baryonic densities. In this article we investigate the possibility that a neutrino effective mass in matter in addition to a very small mass squared difference in vacuum (O(10{sup −9} eV{sup 2})) are the main flavour conversion mechanism acting in neutrino oscillation experiments. We present a parameterization on the environmental effects on neutrino mass that produces the right flavour conversion probabilities for solar and terrestrial neutrinos experiments.

  10. MINOS Sterile Neutrino Search

    SciTech Connect

    Koskinen, David Jason

    2009-02-01

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

  11. Decay of high-energy astrophysical neutrinos.

    PubMed

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

    2003-05-01

    Existing limits on the nonradiative decay of one neutrino to another plus a massless particle (e.g., a singlet Majoron) are very weak. The best limits on the lifetime to mass ratio come from solar neutrino observations and are tau/m greater, similar 10(-4) s/eV for the relevant mass eigenstate(s). For lifetimes even several orders of magnitude longer, high-energy neutrinos from distant astrophysical sources would decay. This would strongly alter the flavor ratios from the phi(nu(e)):phi(nu(mu)):phi(nu(tau))=1:1:1 expected from oscillations alone and should be readily visible in the near future in detectors such as IceCube. PMID:12785996

  12. Probing Exotic Physics With Supernova Neutrinos

    SciTech Connect

    Kelso, Chris; Hooper, Dan

    2010-09-01

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

  13. The Effects of Collective Neutrino Oscillations on Supernova Nucleosynthesis

    NASA Astrophysics Data System (ADS)

    Seadrow, Shaquann; Frohlich, C.; Duan, H.; Friedland, A.; McLaughlin, G.; Keohane, J. W.

    2014-01-01

    A core-collapse supernova originates from the implosion of the electron degenerate core inside a massive star. Runaway electron capture produces on the order of 1057 neutrinos containing about 1053 erg of energy in total. While the vast majority of neutrinos are eventually released, during the first few seconds these neutrinos drive both the dynamics, and likewise the nucleosynthesis, inside the supernova. Recently, our understanding of oscillations among the different flavors of neutrinos (electron, muon, and tau) has significantly improved, allowing us to ask if neutrino flavor change has a significant effect on nucleosynthesis in a core-collapse supernova. To investigate the effects of collective neutrino flavor oscillations, we use the hydrodynamic conditions from a spherically-symmetrical model of the implosion, bounce, and explosion of the 1.4 solar mass core that is inside an 8.8 solar mass star (Huedepohl et al. 2009). We select 20 mass tracers in the ejecta, varying in initial radii, and follow these trajectories for the first 9 seconds following bounce. We include these trajectories into a nuclear reaction network in order to calculate the detailed nucleosynthesis. We use three sets of neutrino reaction rates, all of which are calculated consistently with the conditions in the supernova model: (i) no collective flavor oscillations, (ii) collective oscillations for normal neutrino mass hierarchy, and (iii) collective oscillations for inverted neutrino mass hierarchy. We calculate the detailed nucleosynthesis for each trajectory for all three sets of neutrino rates. We find that the inclusion of collective oscillations (ii or iii) significantly increases the free neutron abundance; however, we obtain similar results regardless of which hierarchy is used. The increase in free neutrons also increases the subsequent rate of neutron capture, but has only a small effect on the predicted final abundances. This work was performed as part of North Carolina State

  14. Charged Cosmic Rays and Neutrinos

    NASA Astrophysics Data System (ADS)

    Kachelrieß, M.

    2013-04-01

    High-energy neutrino astronomy has grown up, with IceCube as one of its main experiments having sufficient sensitivity to test "vanilla" models of astrophysical neutrinos. I review predictions of neutrino fluxes as well as the status of cosmic ray physics. I comment also briefly on an improvement of the Fermi-LAT limit for cosmogenic neutrinos and on the two neutrino events presented by IceCube first at "Neutrino 2012".

  15. Paradoxes of neutrino oscillations

    SciTech Connect

    Akhmedov, E. Kh.; Smirnov, A. Yu.

    2009-08-15

    Despite the theory of neutrino oscillations being rather old, some of its basic issues are still being debated in the literature. We discuss a number of such issues, including the relevance of the 'same energy' and 'same momentum' assumptions, the role of quantum-mechanical uncertainty relations in neutrino oscillations, the dependence of the coherence and localization conditions that ensure the observability of neutrino oscillations on neutrino energy and momentum uncertainties, the question of (in)dependence of the oscillation probabilities on the neutrino production and detection processes, and the applicability limits of the stationary-source approximation. We also develop a novel approach to calculation of the oscillation probability in the wave-packet approach, based on the summation/integration conventions different from the standard one, which allows a new insight into the 'same energy' vs. 'same momentum' problem. We also discuss a number of apparently paradoxical features of the theory of neutrino oscillations.

  16. Neutrinos in Cosmology

    SciTech Connect

    Wong, Yvonne Y. Y.

    2008-01-24

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

  17. Neutrinos: Nature's Ghosts?

    SciTech Connect

    Lincoln, Don

    2013-06-18

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

  18. Neutrinos: Nature's Ghosts?

    ScienceCinema

    Lincoln, Don

    2016-07-12

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

  19. Neutrino Physics at Fermilab

    SciTech Connect

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

    1999-07-09

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

  20. High intensity neutrino beams

    SciTech Connect

    Ichikawa, A. K.

    2015-07-15

    High-intensity proton accelerator complex enabled long baseline neutrino oscillation experiments with a precisely controlled neutrino beam. The beam power so far achieved is a few hundred kW with enourmorous efforts of accelerator physicists and engineers. However, to fully understand the lepton mixing structure, MW-class accelerators are desired. We describe the current intensity-frontier high-energy proton accelerators, their plans to go beyond and technical challenges in the neutrino beamline facilities.

  1. The next-generation liquid-scintillator neutrino observatory LENA

    NASA Astrophysics Data System (ADS)

    Wurm, Michael; Beacom, John F.; Bezrukov, Leonid B.; Bick, Daniel; Blümer, Johannes; Choubey, Sandhya; Ciemniak, Christian; D'Angelo, Davide; Dasgupta, Basudeb; Derbin, Alexander; Dighe, Amol; Domogatsky, Grigorij; Dye, Steve; Eliseev, Sergey; Enqvist, Timo; Erykalov, Alexey; von Feilitzsch, Franz; Fiorentini, Gianni; Fischer, Tobias; Göger-Neff, Marianne; Grabmayr, Peter; Hagner, Caren; Hellgartner, Dominikus; Hissa, Johannes; Horiuchi, Shunsaku; Janka, Hans-Thomas; Jaupart, Claude; Jochum, Josef; Kalliokoski, Tuomo; Kayunov, Alexei; Kuusiniemi, Pasi; Lachenmaier, Tobias; Lazanu, Ionel; Learned, John G.; Lewke, Timo; Lombardi, Paolo; Lorenz, Sebastian; Lubsandorzhiev, Bayarto; Ludhova, Livia; Loo, Kai; Maalampi, Jukka; Mantovani, Fabio; Marafini, Michela; Maricic, Jelena; Marrodán Undagoitia, Teresa; McDonough, William F.; Miramonti, Lino; Mirizzi, Alessandro; Meindl, Quirin; Mena, Olga; Möllenberg, Randolph; Muratova, Valentina; Nahnhauer, Rolf; Nesterenko, Dmitry; Novikov, Yuri N.; Nuijten, Guido; Oberauer, Lothar; Pakvasa, Sandip; Palomares-Ruiz, Sergio; Pallavicini, Marco; Pascoli, Silvia; Patzak, Thomas; Peltoniemi, Juha; Potzel, Walter; Räihä, Tomi; Raffelt, Georg G.; Ranucci, Gioacchino; Razzaque, Soebur; Rummukainen, Kari; Sarkamo, Juho; Sinev, Valerij; Spiering, Christian; Stahl, Achim; Thorne, Felicitas; Tippmann, Marc; Tonazzo, Alessandra; Trzaska, Wladyslaw H.; Vergados, John D.; Wiebusch, Christopher; Winter, Jürgen

    2012-06-01

    As part of the European LAGUNA design study on a next-generation neutrino detector, we propose the liquid-scintillator detector LENA (Low Energy Neutrino Astronomy) as a multipurpose neutrino observatory. The outstanding successes of the Borexino and KamLAND experiments demonstrate the large potential of liquid-scintillator detectors in low-energy neutrino physics. Low energy threshold, good energy resolution and efficient background discrimination are inherent to the liquid-scintillator technique. A target mass of 50 kt will offer a substantial increase in detection sensitivity. At low energies, the variety of detection channels available in liquid scintillator will allow for an energy - and flavor-resolved analysis of the neutrino burst emitted by a galactic Supernova. Due to target mass and background conditions, LENA will also be sensitive to the faint signal of the Diffuse Supernova Neutrino Background. Solar metallicity, time-variation in the solar neutrino flux and deviations from MSW-LMA survival probabilities can be investigated based on unprecedented statistics. Low background conditions allow to search for dark matter by observing rare annihilation neutrinos. The large number of events expected for geoneutrinos will give valuable information on the abundances of Uranium and Thorium and their relative ratio in the Earth's crust and mantle. Reactor neutrinos enable a high-precision measurement of solar mixing parameters. A strong radioactive or pion decay-at-rest neutrino source can be placed close to the detector to investigate neutrino oscillations for short distances and sub-MeV to MeV energies. At high energies, LENA will provide a new lifetime limit for the SUSY-favored proton decay mode into kaon and antineutrino, surpassing current experimental limits by about one order of magnitude. Recent studies have demonstrated that a reconstruction of momentum and energy of GeV particles is well feasible in liquid scintillator. Monte Carlo studies on the

  2. Accelerator neutrino program at Fermilab

    SciTech Connect

    Parke, Stephen J.; /Fermilab

    2010-05-01

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

  3. Scattering of low-energy neutrinos on atomic shells

    SciTech Connect

    Babič, Andrej; Šimkovic, Fedor

    2015-10-28

    We present a derivation of the total cross section for inelastic scattering of low-energy solar neutrinos and reactor antineutrinos on bound electrons, resulting in a transition of the electron to an excited state. The atomic-shell structure of various chemical elements is treated in terms of a nonrelativistic approximation. We estimate the interaction rates for modern neutrino detectors, in particular the Borexino and GEMMA experiments. We establish that in these experiments the effect can be safely neglected, but it could be accessible to future large-volume neutrino detectors with low energy threshold.

  4. Neutrino-nucleus interactions

    SciTech Connect

    Gallagher, H.; Garvey, G.; Zeller, G.P.; /Fermilab

    2011-01-01

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

  5. Neutrinos in supernovae

    SciTech Connect

    Cooperstein, J.

    1986-10-01

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

  6. Muons and neutrinos

    NASA Technical Reports Server (NTRS)

    Stanev, T.

    1986-01-01

    The first generation of large and precise detectors, some initially dedicated to search for nucleon decay has accumulated significant statistics on neutrinos and high-energy muons. A second generation of even better and bigger detectors are already in operation or in advanced construction stage. The present set of experimental data on muon groups and neutrinos is qualitatively better than several years ago and the expectations for the following years are high. Composition studies with underground muon groups, neutrino detection, and expected extraterrestrial neutrino fluxes are discussed.

  7. Nonlinear growing neutrino cosmology

    NASA Astrophysics Data System (ADS)

    Ayaita, Youness; Baldi, Marco; Führer, Florian; Puchwein, Ewald; Wetterich, Christof

    2016-03-01

    The energy scale of dark energy, ˜2 ×10-3 eV , is a long way off compared to all known fundamental scales—except for the neutrino masses. If dark energy is dynamical and couples to neutrinos, this is no longer a coincidence. The time at which dark energy starts to behave as an effective cosmological constant can be linked to the time at which the cosmic neutrinos become nonrelativistic. This naturally places the onset of the Universe's accelerated expansion in recent cosmic history, addressing the why-now problem of dark energy. We show that these mechanisms indeed work in the growing neutrino quintessence model—even if the fully nonlinear structure formation and backreaction are taken into account, which were previously suspected of spoiling the cosmological evolution. The attractive force between neutrinos arising from their coupling to dark energy grows as large as 106 times the gravitational strength. This induces very rapid dynamics of neutrino fluctuations which are nonlinear at redshift z ≈2 . Nevertheless, a nonlinear stabilization phenomenon ensures only mildly nonlinear oscillating neutrino overdensities with a large-scale gravitational potential substantially smaller than that of cold dark matter perturbations. Depending on model parameters, the signals of large-scale neutrino lumps may render the cosmic neutrino background observable.

  8. Neutrinos from the primary proton-proton fusion process in the Sun.

    PubMed

    2014-08-28

    In the core of the Sun, energy is released through sequences of nuclear reactions that convert hydrogen into helium. The primary reaction is thought to be the fusion of two protons with the emission of a low-energy neutrino. These so-called pp neutrinos constitute nearly the entirety of the solar neutrino flux, vastly outnumbering those emitted in the reactions that follow. Although solar neutrinos from secondary processes have been observed, proving the nuclear origin of the Sun's energy and contributing to the discovery of neutrino oscillations, those from proton-proton fusion have hitherto eluded direct detection. Here we report spectral observations of pp neutrinos, demonstrating that about 99 per cent of the power of the Sun, 3.84 × 10(33) ergs per second, is generated by the proton-proton fusion process. PMID:25164748

  9. Neutrinos from the primary proton-proton fusion process in the Sun.

    PubMed

    2014-08-28

    In the core of the Sun, energy is released through sequences of nuclear reactions that convert hydrogen into helium. The primary reaction is thought to be the fusion of two protons with the emission of a low-energy neutrino. These so-called pp neutrinos constitute nearly the entirety of the solar neutrino flux, vastly outnumbering those emitted in the reactions that follow. Although solar neutrinos from secondary processes have been observed, proving the nuclear origin of the Sun's energy and contributing to the discovery of neutrino oscillations, those from proton-proton fusion have hitherto eluded direct detection. Here we report spectral observations of pp neutrinos, demonstrating that about 99 per cent of the power of the Sun, 3.84 × 10(33) ergs per second, is generated by the proton-proton fusion process.

  10. PREFACE: Prospects in Neutrino Physics 2013 - NuPhys2013

    NASA Astrophysics Data System (ADS)

    2015-04-01

    The first "Prospects in Neutrino Physics 2013 - NuPhys2013" conference was held at the Institute of Physics, IoP, London, 19-20 December 2013 and was attended by about 130 delegates from institutions worldwide. Lunch and coffee breaks allowed discussions among delegates and speakers to take place in an informal setting. This conference is unique in discussing the worldwide strategy to address unresolved issues in neutrino physics, and shape the future directions of particle physics. We discussed the current status and focussed especially on the prospects of future experiments, their performance and physics reach. It is particularly timely due to the recent measurements in neutrino physics and planned worldwide experiments. The following topics were addressed: • Theory and Phenomenology Perspectives • Future Long and Short Baseline Neutrino Oscillation Experiments • Reactor neutrino and flux • Neutrinoless double beta decays • Solar, atmospheric, supernova neutrinosNeutrino cosmology in which both the phenomenological and experimental aspects were equally addressed. World-leading experts in the different neutrino areas were invited to give review talks. To encourage and facilitate the participation of early-career researchers and PhD students, a poster session formed a key aspect of this meeting. The conference was organized by Francesca Di Lodovico and Silvia Pascoli. It was sponsored by the IoP through their Topic Research Meeting Grant, and also supported by Durham IPPP, ERC-207282, FP7 invisibles project, Queen Mary University of London.

  11. Signature of a sudden stratospheric warming in the near-ground 7Be flux

    NASA Astrophysics Data System (ADS)

    Pacini, A. A.; Usoskin, I. G.; Mursula, K.; Echer, E.; Evangelista, H.

    2015-07-01

    We present here an evidence that cosmogenic 7Be isotopes produced in the lower stratosphere were measured in near-ground air at Rio de Janeiro, Brazil, after the southern hemispheric Sudden Stratospheric Warming (SSW) of 2002. The analysis presented here is based on a comparison of 7Be data measured around Angra Nuclear Power Station (23°S 44°W) during the last three decades and a model estimate of the near-ground air 7Be concentration using the CRAC:7Be model of cosmogenic production together with a simplified model for atmospheric 7Be deposition that assimilates the regional precipitation data. Our results indicate that an anomalous stratosphere-troposphere coupling associated to the unique SSW of 2002 allowed stratospheric aerosols carrying 7Be to reach the ground level very quickly. This methodology points to an important use of 7Be as a quantitative tracer for stratospheric influence on near-ground air patterns.

  12. High-energy neutrinos from a lunar observatory

    NASA Technical Reports Server (NTRS)

    Shapiro, M. M.; Silberberg, R.

    1985-01-01

    The detection of high-energy (HE) cosmic and solar-flare neutrions near the lunar surface would be feasible at energies much lower than for a terrestrial observatory. At these lower energies ( 10 to the 9th eV), the neutrino background is drastically reduced below that generated by cosmic rays in the Earth's atmosphere. Because of the short mean free path ( 1m) of the progenitor pi and K mesons against nuclear interactions in lunar rocks, the neutrino background would be quite low. At 1 GeV, less than 1% of the pions would decay; at 10 GeV, 0.1%. Thus, if the neutrino flux to be observed is intense enough, and its spectrum is steep enough, then the signal-to-noise ratio is very favorable. The observation of HE neutrinos from solar flares would be dramatically enhanced, especially at lower energies, since the flare spectra are very steep. Detection of these neutrinos on Earth does not appear to be feasible. A remarkable feature of solar flares as viewed in HE neutrinos from a lunar base is that the entire surface of the Sun would be visible.

  13. Extremely high energy cosmic neutrinos and relic neutrinos

    SciTech Connect

    Quigg, Chris; /Fermilab /CERN

    2006-03-01

    I review the essentials of ultrahigh-energy neutrino interactions, show how neutral-current detection and flavor tagging can enhance the scientific potential of neutrino telescopes, and sketch new studies on neutrino encounters with dark matter relics and on gravitational lensing of neutrinos.

  14. Review of neutrino oscillations with sterile and active neutrinos

    NASA Astrophysics Data System (ADS)

    Kisslinger, Leonard S.

    2016-08-01

    Recently neutrino oscillation experiments have shown that it is very likely that there are one or two sterile neutrinos. In this review neutrino oscillations with one, two, three sterile and three active neutrinos, and parameters that are consistent with experiments, are reviewed.

  15. Quantum dissipation in a neutrino system propagating in vacuum and in matter

    NASA Astrophysics Data System (ADS)

    Guzzo, Marcelo M.; de Holanda, Pedro C.; Oliveira, Roberto L. N.

    2016-07-01

    Considering the neutrino state like an open quantum system, we analyze its propagation in vacuum or in matter. After defining what can be called decoherence and relaxation effects, we show that in general the probabilities in vacuum and in constant matter can be written in a similar way, which is not an obvious result for such system. From this result, we analyze the situation where neutrino evolution satisfies the adiabatic limit and use this formalism to study solar neutrinos. We show that the decoherence effect may not be bounded by the solar neutrino data and review some results in the literature, in particular the current results where solar neutrinos were used to put bounds on decoherence effects through a model-dependent approach. We conclude explaining how and why these models are not general and we reinterpret these constraints.

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

    SciTech Connect

    Serpico, Pasquale D.; /Fermilab

    2007-01-01

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

  17. Monte Carlo neutrino oscillations

    SciTech Connect

    Kneller, James P.; McLaughlin, Gail C.

    2006-03-01

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

  18. Muon and neutrino fluxes

    NASA Technical Reports Server (NTRS)

    Edwards, P. G.; Protheroe, R. J.

    1985-01-01

    The result of a new calculation of the atmospheric muon and neutrino fluxes and the energy spectrum of muon-neutrinos produced in individual extensive air showers (EAS) initiated by proton and gamma-ray primaries is reported. Also explained is the possibility of detecting atmospheric nu sub mu's due to gamma-rays from these sources.

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

    NASA Astrophysics Data System (ADS)

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

    2016-01-01

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

  20. Neutrinos and dark matter

    SciTech Connect

    Ibarra, Alejandro

    2015-07-15

    Neutrinos could be key particles to unravel the nature of the dark matter of the Universe. On the one hand, sterile neutrinos in minimal extensions of the Standard Model are excellent dark matter candidates, producing potentially observable signals in the form of a line in the X-ray sky. On the other hand, the annihilation or the decay of dark matter particles produces, in many plausible dark matter scenarios, a neutrino flux that could be detected at neutrino telescopes, thus providing non-gravitational evidence for dark matter. More conservatively, the non-observation of a significant excess in the neutrino fluxes with respect to the expected astrophysical backgrounds can be used to constrain dark matter properties, such as the self-annihilation cross section, the scattering cross section with nucleons and the lifetime.

  1. Dry and wet deposition of 7Be, 210Pb and 137Cs in Monaco air during 1998-2010: seasonal variations of deposition fluxes.

    PubMed

    Pham, Mai K; Povinec, Pavel P; Nies, Hartmut; Betti, Maria

    2013-06-01

    Temporal variations of (7)Be, (210)Pb and (137)Cs activity concentrations in precipitation in Monaco from 1998 to 2010 showed that maxima of (7)Be and (210)Pb deposition fluxes coincide with the peaks of precipitation amounts observed in different months of a year, and most of (7)Be and (210)Pb was washout from the atmosphere by precipitation. The seasonal variations were not uniform from year to year, and the amount of precipitation controlled the deposition fluxes of (7)Be and (210)Pb, which was not the case for (137)Cs. The fractional deposition fluxes of (7)Be and (210)Pb in different seasons were in the order fall > spring > winter > summer, while the fractional amount of precipitation followed the order fall > winter > spring > summer. The fractional deposition fluxes of (137)Cs were found in the order spring > fall > summer > winter. The precipitation-normalized deposition fluxes of (7)Be, (210)Pb and (137)Cs were generally higher during summer. The highest (7)Be/(210)Pb activity ratio was observed in 2010, and the smallest one in 2001, following the influence of the modulation of cosmic rays on the production rates of (7)Be in the atmosphere by solar activity. Activity ratios of (7)Be/(210)Pb observed in winter and fall were generally higher than during summer and spring.

  2. Dark matter astrophysical uncertainties and the neutrino floor

    NASA Astrophysics Data System (ADS)

    O'Hare, Ciaran A. J.

    2016-09-01

    The search for weakly interacting massive particles (WIMPs) by direct detection faces an encroaching background due to coherent neutrino-nucleus scattering. For a given WIMP mass the cross section at which neutrinos constitute a dominant background is dependent on the uncertainty on the flux of each neutrino source, principally from the Sun, supernovae or atmospheric cosmic ray collisions. However there are also considerable uncertainties with regard to the astrophysical ingredients of the predicted WIMP signal. Uncertainties in the velocity of the Sun with respect to the Milky Way dark matter halo, the local density of WIMPs, and the shape of the local WIMP speed distribution all have an effect on the expected event rate in direct detection experiments and hence will change the region of the WIMP parameter space for which neutrinos are a significant background. In this work we extend the neutrino floor calculation to account for the uncertainty in the astrophysics dependence of the WIMP signal. We show the effect of uncertainties on projected discovery limits with an emphasis on low WIMP masses (less than 10 GeV) when solar neutrino backgrounds are most important. We find that accounting for astrophysical uncertainties changes the shape of the neutrino floor as a function of WIMP mass but also causes it to appear at cross sections up to an order of magnitude larger, extremely close to existing experimental limits, indicating that neutrino backgrounds will become an issue sooner than previously thought. We also explore how neutrinos hinder the estimation of WIMP parameters and how astrophysical uncertainties impact the discrimination of WIMPs and neutrinos with the use of their respective time dependencies.

  3. 11B and constraints on neutrino oscillations and spectra from neutrino nucleosynthesis.

    PubMed

    Austin, Sam M; Heger, Alexander; Tur, Clarisse

    2011-04-15

    We study the sensitivity to variations in the triple-alpha and 12C(α,γ)16O reaction rates, of the yield of the neutrino-process isotopes 7Li, 11B, 19F, 138La, and 180Ta in core-collapse supernovae. Compared to solar abundances, less than 15% of 7Li, about 25%-80% of 19F, and about half of 138La is produced in these stars. Over a range of ±2σ for each helium-burning rate, 11B is overproduced and the yield varies by an amount larger than the variation caused by the effects of neutrino oscillations. The total 11B yield, however, may eventually provide constraints on supernova neutrino spectra. PMID:21568548

  4. 11B and constraints on neutrino oscillations and spectra from neutrino nucleosynthesis.

    PubMed

    Austin, Sam M; Heger, Alexander; Tur, Clarisse

    2011-04-15

    We study the sensitivity to variations in the triple-alpha and 12C(α,γ)16O reaction rates, of the yield of the neutrino-process isotopes 7Li, 11B, 19F, 138La, and 180Ta in core-collapse supernovae. Compared to solar abundances, less than 15% of 7Li, about 25%-80% of 19F, and about half of 138La is produced in these stars. Over a range of ±2σ for each helium-burning rate, 11B is overproduced and the yield varies by an amount larger than the variation caused by the effects of neutrino oscillations. The total 11B yield, however, may eventually provide constraints on supernova neutrino spectra.

  5. Beam suppression of the DRAGON recoil separator for 3He(α,γ)7Be

    NASA Astrophysics Data System (ADS)

    Sjue, S. K. L.; Nara Singh, B. S.; Adsley, P.; Buchmann, L.; Carmona-Gallardo, M.; Davids, B.; Fallis, J.; Fulton, B. R.; Galinski, N.; Hager, U.; Hass, M.; Howell, D.; Hutcheon, D. A.; Laird, A. M.; Martin, L.; Ottewell, D.; Reeve, S.; Ruiz, C.; Ruprecht, G.; Triambak, S.

    2013-02-01

    Preliminary studies in preparation for an absolute cross-section measurement of the radiative capture reaction 3He(α,γ)7Be with the DRAGON recoil separator have demonstrated beam suppression >1014 at the 90% confidence level. A measurement of this cross section by observation of 7Be recoils at the focal plane of the separator should be virtually background free.

  6. 7Be radioactive beam production at CIRCE and its utilization in basic and applied physics

    NASA Astrophysics Data System (ADS)

    Limata, Benedicta Normanna; Gialanella, Lucio; Leva, Antonino Di; Cesare, Nicola De; D'Onofrio, Antonio; Gyurky, G.; Rolfs, Claus; Romano, Mario; Rogalla, Detlef; Rossi, Cesare; Russo, Michele; Somorjai, Endre; Terrasi, Filippo

    2008-05-01

    A pure 7Be beam with an energy E = 1-8 MeV is available for nuclear and applied physics at the 3 MV Pelletron tandem accelerator CIRCE in Caserta. The beam is produced using an offline technique. Typical analyzed beam intensities are about 2 ppA, using cathodes with an activity of the order of 200 MBq. The 7Be implantation has been used for both fundamental nuclear physics and applied physics. In particular, different metals have been implanted with 7Be in order to study the influence of the chemical composition and of the number of quasi-free electrons of the host material on the 7Be half-life. In the field of applied physics, the 7Be implantation turns out to be very interesting for wear measurement. In fact, in this case 7Be is used as a depth-sensitive tracer. The continuous detection of the sample activity during the wear allows a high sensitivity measurement of wearing speed. The 7Be beam production at CIRCE, the implantation procedure and the results obtained from the 7Be half-life measurements and the wear characterization of implanted steel samples are described.

  7. Coherent scattering of cosmic neutrinos

    NASA Technical Reports Server (NTRS)

    Opher, R.

    1974-01-01

    It is shown that cosmic neutrino scattering can be non-negligible when coherence effects previously neglected are taken into account. The coherent neutrino scattering cross section is derived and the neutrino index of refraction evaluated. As an example of coherent neutrino scattering, a detector using critical reflection is described which in principle can detect the low energy cosmic neutrino background allowed by the measured cosmological red shift.

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

    SciTech Connect

    Dighe, Amol

    2011-11-23

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

  9. Photonuclear channel of {sup 7}Be production in the Earth's atmosphere

    SciTech Connect

    Bezuglov, M. V.; Malyshevsky, V. S.; Malykhina, T. V.; Torgovkin, A. V.; Fomin, G. V.; Shramenko, B. I.

    2012-04-15

    Measurements of average values of cross sections for the A({gamma},X){sup 7}Be photonuclear reactions on nitrogen, oxygen, and carbon of natural isotopic composition were performed in the energy range from the threshold to 90 MeV. On the basis of the measured cross sections for {sup 7}Be photoproduction and on the basis of the results obtained by simulating the nuclear-electromagnetic cascade in the Earth's atmosphere, the contribution of the photonuclear mechanism to the production of the cosmogenic radioisotope {sup 7}Be in the atmosphere and its latitude dependence were investigated for the first time. It is shown that the contribution of the photonuclear mechanism is commensurate with the contribution of the proton and neutron mechanisms of 7Be production in the atmosphere and that the inclusion of this mechanism is mandatory in analyzing the accumulation and transfer of {sup 7}Be in the planetary boundary layer.

  10. Absolute neutrino mass measurements

    SciTech Connect

    Wolf, Joachim

    2011-10-06

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

  11. Supernova nucleosynthesis and the physics of neutrino oscillation

    SciTech Connect

    Kajino, Toshitaka

    2012-11-20

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

  12. Baryon Triality And Neutrino Masses From An Anomalous FlavorU(1)

    SciTech Connect

    Dreiner, Herbi K.; Luhn, Christoph; Murayama, Hitoshi; Thormeier,Marc

    2007-08-15

    We construct a concise U(1){sub X} Froggatt-Nielsen model in which baryon triality, a discrete gauge Z{sub 3}-symmetry, arises from U(1){sub X} breaking. The proton is thus stable, however, R-parity is violated. With the proper choice of U(1){sub X} charges we can obtain neutrino masses and mixings consistent with an explanation of the atmospheric and solar neutrino anomalies in terms of neutrino oscillations, with no right-handed neutrinos required. The only mass scale apart from M{sub grav} is m{sub soft}.

  13. Asymmetric neutrino production in magnetized proto-neutron stars in fully relativistic mean-field approach

    SciTech Connect

    Maruyama, Tomoyuki; Kajino, Toshitaka; Hidaka, Jun; Takiwaki, Tomoya; Yasutake, Nobutoshi; Kuroda, Takami; Cheoun, Myung-Ki; Ryu, Chung-Yeol; Mathews, Grant J.

    2014-05-02

    We calculate the neutrino production cross-section in the proto-neutron-star matter under a strong magnetic field in the relativistic mean-field approach. We introduce a new parameter-set which can reproduce the 1.96 solar mass neutron star. We find that the production process increases emitted neutrinos along the direction parallel to the magnetic field and decrease those along its opposite direction. It means that resultant asymmetry due to the neutrino absorption and scattering process in the magnetic field becomes larger by the addition of the neutrino production process.

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

    SciTech Connect

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

    2010-05-01

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

  15. Neutrinos from neutron stars

    NASA Technical Reports Server (NTRS)

    Helfand, D. J.

    1979-01-01

    A calculation of the flux of ultra-high energy neutrinos from galactic neutron stars is presented. The calculation is used to determine the number of point sources detectable at the sensitivity threshold of a proposed deep underwater muon and neutrino detector array. The detector array would have a point source detection threshold of about 100 eV/sq cm-sec. Analysis of neutrino luminosities and the number of detectable sources suggests that the deep underwater detector may make a few discoveries. In particular, a suspected neutron star in the Cyg X-3 source seems a promising target for the deep underwater array.

  16. Neutrinos: Nature's Identity Thieves?

    ScienceCinema

    Dr. Don Lincoln

    2016-07-12

    The oscillation of neutrinos from one variety to another has long been suspected, but was confirmed only about 15 years ago. In order for these oscillations to occur, neutrinos must have a mass, no matter how slight. Since neutrinos have long been thought to be massless, in a very real way, this phenomena is a clear signal of physics beyond the known. In this video, Fermilab's Dr Don Lincoln explains how we know it occurs and hints at the rich experimental program at several international laboratories designed to understand this complex mystery.

  17. Neutrinos: Nature's Identity Thieves?

    SciTech Connect

    Dr. Don Lincoln

    2013-07-11

    The oscillation of neutrinos from one variety to another has long been suspected, but was confirmed only about 15 years ago. In order for these oscillations to occur, neutrinos must have a mass, no matter how slight. Since neutrinos have long been thought to be massless, in a very real way, this phenomena is a clear signal of physics beyond the known. In this video, Fermilab's Dr Don Lincoln explains how we know it occurs and hints at the rich experimental program at several international laboratories designed to understand this complex mystery.

  18. Neutrinos: Nature's Identity Thieves?

    ScienceCinema

    Lincoln, Don

    2014-08-07

    The oscillation of neutrinos from one variety to another has long been suspected, but was confirmed only about 15 years ago. In order for these oscillations to occur, neutrinos must have a mass, no matter how slight. Since neutrinos have long been thought to be massless, in a very real way, this phenomena is a clear signal of physics beyond the known. In this video, Fermilab's Dr Don Lincoln explains how we know it occurs and hints at the rich experimental program at several international laboratories designed to understand this complex mystery.

  19. /sup 7/Be in Sargasso Sea and Long Island Sound waters

    SciTech Connect

    Aaboe, E.; Dion, E.P.; Turekian, K.K.

    1981-04-20

    /sup 7/Be was measured in surface waters of the western Sargasso Sea and Long Island Sound. The calculated standing crop in the Sargasso Sea is equal to that predicted from precipitation collectors. Long Island Sound is deficient in /sup 7/Be; virtually none exists in the water column, and less than half of the expected standing crop has been reported for the sediments. A possible sink for the missing /sup 7/Be may be the salt marshes or tidal mud flats ringing Long Island Sound.

  20. Leptonic mixing, family symmetries, and neutrino phenomenology

    SciTech Connect

    Medeiros Varzielas, I. de; Gonzalez Felipe, R.; Serodio, H.

    2011-02-01

    Tribimaximal leptonic mixing is a mass-independent mixing scheme consistent with the present solar and atmospheric neutrino data. By conveniently decomposing the effective neutrino mass matrix associated to it, we derive generic predictions in terms of the parameters governing the neutrino masses. We extend this phenomenological analysis to other mass-independent mixing schemes which are related to the tribimaximal form by a unitary transformation. We classify models that produce tribimaximal leptonic mixing through the group structure of their family symmetries in order to point out that there is often a direct connection between the group structure and the phenomenological analysis. The type of seesaw mechanism responsible for neutrino masses plays a role here, as it restricts the choices of family representations and affects the viability of leptogenesis. We also present a recipe to generalize a given tribimaximal model to an associated model with a different mass-independent mixing scheme, which preserves the connection between the group structure and phenomenology as in the original model. This procedure is explicitly illustrated by constructing toy models with the transpose tribimaximal, bimaximal, golden ratio, and hexagonal leptonic mixing patterns.

  1. Detecting the Neutrino

    NASA Astrophysics Data System (ADS)

    Arns, Robert G.

    In 1930 Wolfgang Pauli suggested that a new particle might be required to make sense of the radioactive-disintegration mode known as beta decay. This conjecture initially seemed impossible to verify since the new particle, which became known as the neutrino, was uncharged, had zero or small mass, and interacted only insignificantly with other matter. In 1951 Frederick Reines and Clyde L. Cowan, Jr., of the Los Alamos Scientific Laboratory undertook the difficult task of detecting the free neutrino by observing its inverse beta-decay interaction with matter. They succeeded in 1956. The neutrino was accepted rapidly as a fundamental particle despite discrepancies in reported details of the experiments and despite the absence of independent verification of the result. This paper describes the experiments, examines the nature of the discrepancies, and discusses the circumstances of the acceptance of the neutrino's detection by the physics community.

  2. Light sterile neutrinos

    NASA Astrophysics Data System (ADS)

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

    2015-03-01

    The theory and phenomenology of light sterile neutrinos at the eV mass scale is reviewed. The reactor, gallium and Liquid Scintillator Neutrino Detector anomalies are briefly described and interpreted as indications of the existence of short-baseline oscillations which require the existence of light sterile neutrinos. The global fits of short-baseline oscillation data in 3 + 1 and 3 + 2 schemes are discussed, together with the implications for β-decay and neutrinoless double-β decay. The cosmological effects of light sterile neutrinos are briefly reviewed and the implications of existing cosmological data are discussed. The review concludes with a summary of future perspectives. This review is dedicated to the memory of Hai-Wei Long, our dear friend and collaborator, who passed away on 29 May 2015. He was an exceptionally kind person and an enthusiastic physicist. We deeply miss him.

  3. Light sterile neutrinos

    NASA Astrophysics Data System (ADS)

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

    2016-03-01

    The theory and phenomenology of light sterile neutrinos at the eV mass scale is reviewed. The reactor, gallium and Liquid Scintillator Neutrino Detector anomalies are briefly described and interpreted as indications of the existence of short-baseline oscillations which require the existence of light sterile neutrinos. The global fits of short-baseline oscillation data in 3 + 1 and 3 + 2 schemes are discussed, together with the implications for β-decay and neutrinoless double-β decay. The cosmological effects of light sterile neutrinos are briefly reviewed and the implications of existing cosmological data are discussed. The review concludes with a summary of future perspectives. This review is dedicated to the memory of Hai-Wei Long, our dear friend and collaborator, who passed away on 29 May 2015. He was an exceptionally kind person and an enthusiastic physicist. We deeply miss him.

  4. Neutrinos in Cosmology

    SciTech Connect

    Davidson, Sacha

    2008-02-21

    Neutrinos can contribute to various episodes of the evolution of the Universe. For instance, in the seesaw model, they may generate the baryon asymmetry of the Universe via leptogenesis. This conference proceedings briefly reviews lepton flavour effects in thermal leptogenesis.

  5. ICFA neutrino panel report

    NASA Astrophysics Data System (ADS)

    Long, K.

    2015-07-01

    In the summer of 2013 the International Committee on Future Accelerators (ICFA) established a Neutrino Panel with the mandate: "To promote international cooperation in the development of the accelerator-based neutrino-oscillation program and to promote international collaboration in the development of a neutrino factory as a future intense source of neutrinos for particle physics experiments." In its first year the Panel organised a series of regional Town Meetings to collect input from the community and to receive reports from the regional planning exercises. The Panel distilled its findings and presented them in a report to ICFA [1]. In this contribution the formation and composition of the Panel are presented together with a summary of the Panel's findings from the three Regional Town Meetings. The Panel's initial conclusions are then articulated and the steps that the Panel seeks to take are outlined.

  6. ICFA neutrino panel report

    SciTech Connect

    Long, K.

    2015-07-15

    In the summer of 2013 the International Committee on Future Accelerators (ICFA) established a Neutrino Panel with the mandate: <<neutrino-oscillation program and to promote international collaboration in the development of a neutrino factory as a future intense source of neutrinos for particle physics experiments. >>>In its first year the Panel organised a series of regional Town Meetings to collect input from the community and to receive reports from the regional planning exercises. The Panel distilled its findings and presented them in a report to ICFA [1]. In this contribution the formation and composition of the Panel are presented together with a summary of the Panel’s findings from the three Regional Town Meetings. The Panel’s initial conclusions are then articulated and the steps that the Panel seeks to take are outlined.

  7. Ultrahigh energy neutrino interactions

    NASA Astrophysics Data System (ADS)

    Domokos, G.; Elliot, B.; Kovesi-Domokos, S.; Mrenna, S.

    1990-03-01

    Ultrahigh energy neutrinos are valuable probes of physics beyond the Standard Model. Neutrinos of the highest energies are emitted by point sources in the sky. We review briefly the predictions of the Standard Model concerning neutrino interactions. We further argue that a number of preon models designed to overcome some difficulties of the Standard Model leads to a blurring of the distinction between leptons and quarks. As a consequence, at sufficiently high energies neutrinos acquire ``anomalous'' interactions. While this phenomenon can probably explain the observed muon excess in extensive air showers (EAS), it can be also tested by studying the absorption of the primaries on the cosmic microwave background. We discuss some observations to be performed in the search of such ``new physics'' beyond the Standard Model.

  8. WMAPping out neutrino masses

    SciTech Connect

    Pierce, Aaron; Murayama, Hitoshi

    2003-10-28

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

  9. Monitoring (7)Be and tritium in rainwater in Daejeon, Korea and its significance.

    PubMed

    Kim, K J; Choi, Y; Yoon, Y-Y

    2016-03-01

    We investigated the concentrations of beryllium-7 and tritium in rainwater along with sodium concentration in the region of Daejeon, Korea for 7 months. The results demonstrate that (7)Be in rainwater is inversely proportional to the amount of sodium present and proportional to the rainfall. Also, it was observed that tritium reaches ground level about a month later than (7)Be. This study will guide prospective geological research applications associated with cosmogenic nuclides especially in rainwater for the Korean region. PMID:26688366

  10. The Sudbury Neutrino Observatory

    NASA Astrophysics Data System (ADS)

    Ewan, G. T.

    1992-04-01

    The Sudbury Neutrino Observatory (SNO) detector is a 1000 ton heavy water (D2O) Cherenkov detector designed to study neutrinos from the sun and other astrophysical sources. The use of heavy water allows both electron neutrinos and all other types of neutrinos to be observed by three complementary reactions. The detector will be sensitive to the electron neutrino flux and energy spectrum shape and to the total neutrino flux irrespective of neutrino type. These measurements will provide information on both vacuum neutrino oscillations and matter-enhanced oscillations, the MSW effect. In the event of a supernova it will be very sensitive to muon and tau neutrinos as well as the electron neutrinos emitted in the initial burst, enabling sensitive mass measurements as well as providing details of the physics of stellar collapse. On behalf of the Sudbury Neutrino Observatory (SNO) Collaboration : H.C . Evans, G.T . Ewan, H.W. Lee, J .R . Leslie, J .D. MacArthur, H .-B . Mak, A.B . McDonald, W. McLatchie, B.C . Robertson, B. Sur, P. Skensved (Queen's University) ; C.K . Hargrove, H. Mes, W.F. Davidson, D. Sinclair, 1 . Blevis, M. Shatkay (Centre for Research in Particle Physics) ; E.D. Earle, G.M. Milton, E. Bonvin, (Chalk River Laboratories); J .J . Simpson, P. Jagam, J . Law, J .-X . Wang (University of Guelph); E.D . Hallman, R.U. Haq (Laurentian University); A.L. Carter, D. Kessler, B.R . Hollebone (Carleton University); R. Schubank . C.E . Waltha m (University of British Columbia); R.T. Kouzes, M.M. Lowry, R.M. Key (Princeton University); E.W. Beier, W. Frati, M. Newcomer, R. Van Berg (University of Penn-sylvania), T.J . Bowles, P.J . Doe, S.R . Elliott, M.M. Fowler, R.G.H. Robertson, D.J . Vieira, J .B . Wilhelmy, J .F. Wilker-son, J .M. Wouters (Los Alamos National Laboratory) ; E. Norman, K. Lesko, A. Smith, R. Fulton, R. Stokstad (Lawrence Berkeley Laboratory), N.W. Tanner, N. JCIILY, P. Trent, J . Barton, D.L . Wark (University of Oxford).

  11. Effective Majorana neutrino decay

    NASA Astrophysics Data System (ADS)

    Duarte, Lucía; Romero, Ismael; Peressutti, Javier; Sampayo, Oscar A.

    2016-08-01

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

  12. Cosmological and supernova neutrinos

    NASA Astrophysics Data System (ADS)

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

    2014-06-01

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

  13. Neutrinos from GRBs cannonballs

    NASA Astrophysics Data System (ADS)

    Hubbard, J. R.; Ferry, S.

    We present a new estimation of the production of prompt neutrinos in the Cannonball Model of Gamma Ray Bursts proposed by Dar and De Rújula. Interactions between nucleons in the cannonballs and nucleons in the supernova shell are calculated in the rest frame of the shocked matter produced by these interactions. We explore the neutrino yield as a function of the parameters of the model.

  14. Cosmological and supernova neutrinos

    SciTech Connect

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

    2014-06-24

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

  15. Neutrino experiments: Hierarchy, CP, CPT

    NASA Astrophysics Data System (ADS)

    Gupta, Manmohan; Randhawa, Monika; Singh, Mandip

    2016-07-01

    We present an overview of our recent investigations regarding the prospects of ongoing neutrino experiments as well as future experiments in determining few of the most important unknowns in the field of neutrino physics, specifically the neutrino mass ordering and leptonic CP-violation phase. The effect of matter oscillations on the neutrino oscillation probabilities has been exploited in resolving the degeneracy between the neutrino mass ordering and the CP violation phase in the leptonic sector. Further, we estimate the extent of extrinsic CP and CPT violation in the experiments with superbeams as well as neutrino factories.

  16. Neutrino Detectors: Challenges and Opportunities

    SciTech Connect

    Soler, F. J. P.

    2011-10-06

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

  17. Electromagnetic properties of massive neutrinos

    SciTech Connect

    Dobrynina, A. A. Mikheev, N. V.; Narynskaya, E. N.

    2013-10-15

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

  18. Nonthermal cosmic neutrino background

    NASA Astrophysics Data System (ADS)

    Chen, Mu-Chun; Ratz, Michael; Trautner, Andreas

    2015-12-01

    We point out that, for Dirac neutrinos, in addition to the standard thermal cosmic neutrino background (C ν B ), there could also exist a nonthermal neutrino background with comparable number density. As the right-handed components are essentially decoupled from the thermal bath of standard model particles, relic neutrinos with a nonthermal distribution may exist until today. The relic density of the nonthermal (nt) background can be constrained by the usual observational bounds on the effective number of massless degrees of freedom Neff and can be as large as nν nt≲0.5 nγ. In particular, Neff can be larger than 3.046 in the absence of any exotic states. Nonthermal relic neutrinos constitute an irreducible contribution to the detection of the C ν B and, hence, may be discovered by future experiments such as PTOLEMY. We also present a scenario of chaotic inflation in which a nonthermal background can naturally be generated by inflationary preheating. The nonthermal relic neutrinos, thus, may constitute a novel window into the very early Universe.

  19. Annual variation of (7)Be soil inventory in a semiarid region of central Argentina.

    PubMed

    Lohaiza, F; Velasco, H; Juri Ayub, J; Rizzotto, M; Di Gregorio, D E; Huck, H; Valladares, D L

    2014-04-01

    Reliable information on environmental radionuclides atmospheric entrance, and their distribution along the soil profile, is a necessary condition for using these soil and sediment tracers to investigate key environmental processes. To address this need, (7)Be content in rainwater and the wet deposition in a semiarid region at San Luis Province, Argentina, were studied. Following these researches, in the same region, we have assessed the (7)Be content along a soil profile, during 2.5 years from September 2009 to January 2012. As expected, the specific activity values in soil samples in the wet period (November-April) were higher than in the dry period (May-October). During the investigated period (2009 - beginning 2012) and for all sampled points, the maximum value of the (7)Be specific activity (Bq kg(-1)) was measured at the surface level. A typical decreasing exponential function of (7)Be areal activity (Bq m(-2)) with soil mass depth (kg m(-2)) was found and the key distribution parameters were determined for each month. The minimum value of areal activity was 51 Bq m(-2) in August, and the maximum was 438 Bq m(-2) in February. The relaxation mass depth ranges from 2.9 kg m(-2) in March to 1.3 kg m(-2) in August. (7)Be wet deposition can explain in a very significant proportion the (7)Be inventory in soil. During the period of winds in the region (September and October), the (7)Be content in soil was greater than the expected contribution from wet deposition, situation that is compatible with a higher relative contribution of dry deposition at this period of the year. PMID:24487256

  20. Temporal variations of 7Be and 210Pb activity in aerosols at Xiamen, China

    NASA Astrophysics Data System (ADS)

    Huang, Dekun

    2016-04-01

    The radionuclides serve as powerful tracers to identify and quantify several atmospheric processes, such as source, transport and mixing of air masses, air masses exchanging between various atmospheric layers, residence times of atmospheric gasses and pollutants. 7Be and 210Pb activities in aerosols were measurement from October, 2013 to September, 2015 at Xiamen (24°26'7.44″N, 118°5'31.30″N) in South China. The activity of 7Be and 210Pb in aerosols from 2013 to 2015 in Xiamen ranged from 0.26 to 9.05 (mean:4.15) mBq m-3 and from 0.14 to 2.64 (mean:1.05) mBq m-3, respectively. The mean activity of 7Be was comparable with the activities of other places in the same latitude, while the mean activity of 210Pb was lower than the activity of the locations at high altitudes. The possible reason is that Xiamen is a coastal city located on southwest Pacific. The activities of 7Be and 210Pb had a commonly low value in summer (July-September) and a high value in autumn (October-December), it may be controlled by the rainfall. There is significant relationship between the monthly 210Pb activities and the concentration of PM 2.5 and PM 10. In contrast, monthly 7Be activities only show significant correlation with the concentration of PM 10, which implies that 7Be and 210Pb can be used to trace the different sources of the aerosols. And the dry 7Be depositional fluxes increased with latitude along the coast of China (R2=0.92, n=8).

  1. Annual variation of (7)Be soil inventory in a semiarid region of central Argentina.

    PubMed

    Lohaiza, F; Velasco, H; Juri Ayub, J; Rizzotto, M; Di Gregorio, D E; Huck, H; Valladares, D L

    2014-04-01

    Reliable information on environmental radionuclides atmospheric entrance, and their distribution along the soil profile, is a necessary condition for using these soil and sediment tracers to investigate key environmental processes. To address this need, (7)Be content in rainwater and the wet deposition in a semiarid region at San Luis Province, Argentina, were studied. Following these researches, in the same region, we have assessed the (7)Be content along a soil profile, during 2.5 years from September 2009 to January 2012. As expected, the specific activity values in soil samples in the wet period (November-April) were higher than in the dry period (May-October). During the investigated period (2009 - beginning 2012) and for all sampled points, the maximum value of the (7)Be specific activity (Bq kg(-1)) was measured at the surface level. A typical decreasing exponential function of (7)Be areal activity (Bq m(-2)) with soil mass depth (kg m(-2)) was found and the key distribution parameters were determined for each month. The minimum value of areal activity was 51 Bq m(-2) in August, and the maximum was 438 Bq m(-2) in February. The relaxation mass depth ranges from 2.9 kg m(-2) in March to 1.3 kg m(-2) in August. (7)Be wet deposition can explain in a very significant proportion the (7)Be inventory in soil. During the period of winds in the region (September and October), the (7)Be content in soil was greater than the expected contribution from wet deposition, situation that is compatible with a higher relative contribution of dry deposition at this period of the year.

  2. Trapped ionic simulation of neutrino electromagnetic properties in neutrino oscillation

    NASA Astrophysics Data System (ADS)

    Wang, Z. S.; Cai, Xiaoya; Pan, Hui

    2015-11-01

    We present an approach to study neutrino electromagnetic properties by simulating neutrino oscillation in both dense background matter and external electromagnetic field in terms of trapped coupling ions. We find that the neutrino and anti-neutrino productions can be simulated by using large enough diagonal matter potentials and external magnetic field. We further show that the transition probabilities of flavor neutrino have rich features and time scales corresponding to the neutrino magnetic moments and electric millicharges. Especially, such features and scales can be achieved by tuning the laser parameters. At last, we show that the millicharge and magnetic moments can be detected in terms of flavor neutrino transition probabilities in the trapped ion system. Our approach provides a useful clue to measure the neutrino electromagnetic properties for experimental realization.

  3. Massive Cherenkov neutrino facilities…their evolution, their future: Twenty-five years at these International Neutrino Conferences

    NASA Astrophysics Data System (ADS)

    Sulak, Lawrence R.

    2005-06-01

    This review traces the evolution of massive water Cherenkov tracking calorimeters. Pioneering concepts, first presented in this conference a quarter of a century ago, have led to 1) IMB, the first large detector (10kT), which was designed primarily to search for proton decay, and secondarily to be sensitive to supernova neutrinos and atmospheric oscillations, and 2) Dumand, an attempt to initiate the search for TeV astrophysical neutrinos with a prototype for a 1 km3 telescope. The concepts and initial work on IMB influenced subsequent detectors: Kamiokande, Super-K, SNO, and, in part, Kamland. These detectors have to their credit the elucidation of the physics of atmospheric, solar, reactor and supernova neutrinos. With the advent of the K2K beam, controlled accelerator neutrinos confirm the atmospheric studies. The path breaking developments of Dumand now are incorporated in the high-volume Amanda and Antares detectors, as well as their sequels, IceCube and the proposed Cubic Kilometer detector. The future (ultimate?) facilities have new physics challenges: A high-resolution megaton detector, eventually coupled with an intense accelerator neutrino source, is critical for precision studies of neutrino oscillation parameters and for the potential discovery of CP violation in the lepton sector. The Gigaton TeV neutrino telescopes (IceCube and Cubic Kilometer) seek to open high-energy neutrino astronomy, still an elusive goal. (Amanda, IceCube, and UNO, as well as Minos, Icarus and other large neutrino facilities using non-Cherenkov technologies, are treated in other contributions to this volume.)

  4. Tau neutrinos favored over sterile neutrinos in atmospheric muon neutrino oscillations.

    PubMed

    Fukuda, S; Fukuda, Y; Ishitsuka, M; Kajita, T; Kameda, J; Kaneyuki, K; Kobayashi, K; Koshio, Y; Miura, M; Moriyama, S; Nakahata, M; Nakayama, S; Obayashi, Y; Okada, A; Okumura, K; Sakurai, N; Shiozawa, M; Suzuki, Y; Takeuchi, H; Takeuchi, Y; Toshito, T; Totsuka, Y; Yamada, S; Earl, M; Habig, A; Kearns, E; Messier, M D; Scholberg, K; Stone, J L; Sulak, L R; Walter, C W; Goldhaber, M; Barszczak, T; Casper, D; Gajewski, W; Kropp, W R; Mine, S; Price, L R; Smy, M; Sobel, H W; Vagins, M R; Ganezer, K S; Keig, W E; Ellsworth, R W; Tasaka, S; Kibayashi, A; Learned, J G; Matsuno, S; Takemori, D

    2000-11-01

    The previously published atmospheric neutrino data did not distinguish whether muon neutrinos were oscillating into tau neutrinos or sterile neutrinos, as both hypotheses fit the data. Using data recorded in 1100 live days of the Super-Kamiokande detector, we use three complementary data samples to study the difference in zenith angle distribution due to neutral currents and matter effects. We find no evidence favoring sterile neutrinos, and reject the hypothesis at the 99% confidence level. On the other hand, we find that oscillation between muon and tau neutrinos suffices to explain all the results in hand.

  5. No-neutrino double beta decay: more than one neutrino

    SciTech Connect

    Rosen, S.P.

    1983-01-01

    Interference effects between light and heavy Majorana neutrinos in the amplitude for no-neutrino double beta decay are discussed. The effects include an upper bound on the heavy neutrino mass, and an A dependence for the effective mass extracted from double beta decay. Thus the search for the no-neutrino decay mode should be pursued in several nuclei, and particularly in Ca/sup 48/, where the effective mass may be quite large.

  6. Neutron Interactions With 7Be and the Primordial 7Li Problem

    NASA Astrophysics Data System (ADS)

    Kading, Emily E.; Gai, Moshe; Kahn, Merav; Lee, Morit; Tessler, Moshe; Paul, Michael; Weiss, Aryeh; Berkovitz, Dan; Halfon, Shlomi; Kijel, Danny; Kreisel, Arik; Shor, Asher; Silverman, Ido; Weissman, Leonid; Hass, Michael; Mukul, Ish; Maugeri, Emilio A.; Dressler, Rugard; Schumann, Dorothea; Heinitz, Stephan; Stora, Thierry; Ticehurst, David; Howell, Calvin R.

    2015-10-01

    We study the interaction of neutrons with 7Be to estimate the direct destruction of 7Be during BBN; i.e. the predicted primordial 7Li. We plan to use a 7Be target (15 GBq) prepared by electro-deposition at PSI. The intense neutron flux of up to 5×1010 n/sec/cm2 are produced with proton beams and a high power liquid-lithium target (LiLiT) from the SARAF (phase I) facility in Israel. The outgoing particles will be measured using CR-39 plates that were tested to be insensitive to the large neutron flux and were calibrated with protons and alpha-particles from the TUNL. In a separate stage implanted 7Be target will be prepared at the ISOLDE facility of CERN. The results of the calibration of the CR-39 plates and the test experiment at SARAF with 10B target as well as a very low activity 7Be test target prepared at PSI, will be presented. Supported in part by the US-Israel Binational Science Foundation Proposal No. 2012098, the USDOE Grants No. DE-FG02-94ER40870, DE-FG02-97ER41033, and the Pazi Foundation, Israel.

  7. Atmospheric deposition patterns of (210)Pb and (7)Be in Cienfuegos, Cuba.

    PubMed

    Alonso-Hernández, Carlos M; Morera-Gómez, Yasser; Cartas-Águila, Héctor; Guillén-Arruebarrena, Aniel

    2014-12-01

    The radiometric composition of bulk deposition samples, collected monthly for one year, February 2010 until January 2011, at a site located in Cienfuegos (22° 03' N, 80° 29' W) (Cuba), are analysed in this paper. Measurement of (7)Be and (210)Pb activity concentrations were carried out in 12 bulk deposition samples. The atmospheric deposition fluxes of (7)Be and (210)Pb are in the range of 13.2-132 and 1.24-8.29 Bq m(-2), and their mean values are: 56.6 and 3.97 Bq m(-2), respectively. The time variations of the different radionuclide have been discussed in relation with meteorological factors and the mean values have been compared to those published in recent literature from other sites located at different latitudes. The annual average flux of (210)Pb and (7)Be were 47 and 700 Bq m(-2) y(-1), respectively. Observed seasonal variations of deposition data are explained in terms of different environmental features. The atmospheric deposition fluxes of (7)Be and (210)Pb were moderately well correlated with precipitation and well correlated with one another. The (210)Pb/(7)Be ratios in the monthly depositions samples varied in the range of 0.05-0.10 and showed a strong correlation with the number of rainy days.

  8. Atmospheric neutrinos in ice and measurement of neutrino oscillation parameters

    SciTech Connect

    Fernandez-Martinez, Enrique; Giordano, Gerardo; Mocioiu, Irina; Mena, Olga

    2010-11-01

    The main goal of the IceCube Deep Core array is to search for neutrinos of astrophysical origins. Atmospheric neutrinos are commonly considered as a background for these searches. We show that the very high statistics atmospheric neutrino data can be used to obtain precise measurements of the main oscillation parameters.

  9. Elastic scattering measurements for {sup 7}Be+{sup 27}Al system at RIBRAS facility

    SciTech Connect

    Morcelle, V.; Lichtenthaeler, R.; Morais, M. C.; Lepine-Szily, A.; Guimaraes, V.; Faria, P. N. de; Gasques, L.; Pires, K. C. C.; Condori, R. P.; Gomes, P. R. S.; Lubian, J.; Mendes, D. R. Jr.; Barioni, A.; Shorto, J. M. B.; Zamora, J. C.

    2013-05-06

    Elastic scattering angular distribution measurements of {sup 7}Be+{sup 27}Al system were performed at the laboratory energy of 15.6 MeV. The {sup 7}Be secondary beam was produced by the proton transfer reaction {sup 3}He({sup 6}Li,{sup 7}Be) and impinged on {sup 27}Al and {sup 197}Au targets, using the Radioactive Ion Beam (RIB) facility, RIBRAS. The elastic angular distribution was obtained within the angular range of 15{sup 0} - 80{sup 0} at the center of mass frame. Optical model calculations have been performed using the Woods- Saxon form factors and the Sao Paulo potential to fit the experimental data. The total reaction cross section was derived.

  10. Secondary atmospheric tau neutrino production

    SciTech Connect

    Bulmahn, Alexander; Hall Reno, Mary

    2010-09-01

    We evaluate the flux of tau neutrinos produced from the decay of pair produced taus from incident muons using a cascade equation analysis. To solve the cascade equations, our numerical result for the tau production Z moment is given. Our results for the flux of tau neutrinos produced from incident muons are compared to the flux of tau neutrinos produced via oscillations and the direct prompt atmospheric tau neutrino flux. Results are given for both downward and upward going neutrinos fluxes and higher zenith angles are discussed. We conclude that the direct prompt atmospheric tau neutrino flux dominates these other atmospheric sources of tau neutrinos for neutrino energies larger than a few TeV for upward fluxes, and over a wider range of energy for downward fluxes.

  11. Hadronization processes in neutrino interactions

    SciTech Connect

    Katori, Teppei; Mandalia, Shivesh

    2015-10-15

    Next generation neutrino oscillation experiments utilize details of hadronic final states to improve the precision of neutrino interaction measurements. The hadronic system was often neglected or poorly modelled in the past, but they have significant effects on high precision neutrino oscillation and cross-section measurements. Among the physics of hadronic systems in neutrino interactions, the hadronization model controls multiplicities and kinematics of final state hadrons from the primary interaction vertex. For relatively high invariant mass events, many neutrino experiments rely on the PYTHIA program. Here, we show a possible improvement of this process in neutrino event generators, by utilizing expertise from the HERMES experiment. Finally, we estimate the impact on the systematics of hadronization models for neutrino mass hierarchy analysis using atmospheric neutrinos such as the PINGU experiment.

  12. Sudbury Neutrino Observatory. Annual technical progress report, July 1, 1991--June 30, 1992

    SciTech Connect

    Beier, E.W.

    1992-03-01

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

  13. Neutrino Masses and Flavor Mixing

    NASA Astrophysics Data System (ADS)

    Xing, Zhi-zhong

    2010-06-01

    I give a theoretical overview of some basic properties of massive neutrinos in these lectures. Particular attention is paid to the origin of neutrino masses, the pattern of lepton flavor mixing, the feature of leptonic CP violation and the electromagnetic properties of massive neutrinos. I highlight the TeV seesaw mechanisms as a possible bridge between neutrino physics and collider physics in the era characterized by the Large Hadron Collider.

  14. Gravitational Lensing of Supernova Neutrinos

    SciTech Connect

    Mena, Olga; Mocioiu, Irina; Quigg, Chris; /Fermilab

    2006-10-01

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

  15. Neutrino sea scope takes shape

    NASA Astrophysics Data System (ADS)

    Cartlidge, Edwin

    2016-03-01

    A consortium of European physicists building a vast neutrino detector on the floor of the Mediterranean Sea has unveiled the science it will carry out. The Cubic Kilometre Neutrino Telescope (KM3NeT) will use strings of radiation detectors arranged in a 3D network to measure the light emitted when neutrinos very occasionally interact with the surrounding sea water.

  16. Elastic scattering of {sup 6}He and {sup 7}Be on a {sup 9}Be target

    SciTech Connect

    Pires, K. C. C.; Lichtenthaeler, R.; Mukha, I.; Moro, A. M.; Gomez-Camacho, J.

    2010-04-26

    The elastic scattering data for the {sup 6}He+{sup 9}Be and {sup 7}Be+{sup 9}Be reactions, measured at E{sub lab} = 16.2 MeV and E{sub lab} = 23.7 MeV respectively, are presented and analyzed using the optical model and coupled-channels formalisms.

  17. Influence of precipitation on (7)Be concentrations in air as measured by CTBTO global monitoring system.

    PubMed

    Kusmierczyk-Michulec, J; Gheddou, A; Nikkinen, M

    2015-06-01

    Data collected by the International Monitoring System (IMS) during 2009-2012 were used to study influence of precipitation and relative humidity on changes in (7)Be concentrations in atmosphere. The significant decrease in (7)Be concentrations, corresponding to measurements collected by stations located within Intertropical Convergence Zone (ITCZ) is demonstrated. This effect can be attributed to the process of enhanced wet deposition within the ITCZ. To quantify this effect data collected by IMS stations within ITCZ were thoroughly analyzed. It was found that the atmospheric content of (7)Be strongly decreases under the rain conditions. The rain mediated depletion of (7)Be to half of its before rain value, needs about 62 h in case of light precipitation, while in the case of moderate precipitation about 38 h is needed. In addition the evaluated impact of humidity showed that increase in relative humidity by 20%, for example from 70% ± 5% to 90% ± 5% causes almost a double decrease in beryllium concentration in surface air.

  18. 7Be(p,(gamma))8B S-factor From Ab Initio Wave Functions

    SciTech Connect

    Navratil, P; Bertulani, C; Caurier, E

    2005-08-15

    Nuclear structure of {sup 7}Be, {sup 8}B and {sup 7,8}Li is studied within the ab initio no-core shell model (NCSM). Starting from the high-precision CD-Bonn 2000 nucleon-nucleon (NN) interaction, wave functions of {sup 7}Be and {sup 8}B bound states are obtained in basis spaces up to 10{h_bar}{Omega} and used to calculate channel cluster form factors (overlap integrals) of the {sup 8}B ground state with {sup 7}Be+p. Due to the use of the harmonic oscillator (HO) basis, the overlap integrals have incorrect asymptotic properties. We fix this problem in two alternative ways. First, by a Woods-Saxon (WS) potential solution fit to the interior of the NCSM overlap integrals. Second, by a direct matching with the Whittaker function. The corrected overlap integrals are then used for the {sup 7}Be(p,{gamma}){sup 8}B S-factor calculation. We study the convergence of the S-factor with respect to the NCSM HO frequency and the model space size. Our S-factor results are in agreement with recent direct measurement data.

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

    SciTech Connect

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

    2010-06-01

    We investigate explosive nucleosynthesis in a delayed neutrino-driven, supernova explosion aided by standing accretion shock instability (SASI), based on two-dimensional hydrodynamic simulations of the explosion of a 15 M{sub c}entre dot star. We take into accounts neutrino heating and cooling as well as change in electron fraction due to weak interactions appropriately, in the two-dimensional simulations. We assume the isotropic emission of neutrinos from the neutrino spheres with given luminosities. and the Fermi-Dirac distribution of given temperatures. We find that the stalled shock revives due to the neutrino heating aided by SASI for cases with L{sub n}u{sub e}>=3.9x10{sup 52}ergss{sup -1} and the as-pherical shock passes through the outer layers of the star (>=10,000 km), with the explosion energies of approx10{sup 51}ergs.Next we examine abundances and masses of the supernova ejecta. We find that masses of the ejecta and {sup 56}Ni correlate with the neutrino luminosity, and {sup 56}Ni mass is comparable to that observed in SN 1987A. We also find that abundance pattern of the supernova ejecta is similar to that of the solar system, for cases with high explosion energies of >10{sup 51}ergs. We emphasize that {sup 64}Zn, which is underproduced in the spherical case, is abundantly produced in slightly neutron-rich ejecta.

  20. Neutrino astrophysics: a new tool for exploring the universe.

    PubMed

    Waxman, Eli

    2007-01-01

    In the past four decades a new type of astronomy has emerged, where instead of looking up into the sky, "telescopes" are buried miles underground or deep under water or ice and search not for photons (that is, light), but rather for particles called neutrinos. Neutrinos are nearly massless particles that interact very weakly with matter. The detection of neutrinos emitted by the Sun and by a nearby supernova provided direct tests of the theory of stellar evolution and led to modifications of the standard model describing the properties of elementary particles. At present, several very large neutrino detectors are being constructed, aiming at the detection of the most powerful sources of energy and particles in the universe. The hope is that the detection of neutrinos from these sources, which are extra-Galactic and are most likely powered by mass accretion onto black holes, will not only allow study of the sources, but, much like solar neutrinos, will also provide new information about fundamental properties of matter.

  1. SOX: search for short baseline neutrino oscillations with Borexino

    NASA Astrophysics Data System (ADS)

    Vivier, M.; Agostini, M.; Altenmüller, K.; Appel, S.; Bellini, G.; Benziger, J.; Berton, N.; Bick, D.; Bonfini, G.; Bravo, D.; Caccianiga, B.; Calaprice, F.; Caminata, A.; Cavalcante, P.; Chepurnov, A.; Choi, K.; Cribier, M.; D'Angelo, D.; Davini, S.; Derbin, A.; Di Noto, L.; Drachnev, I.; Durero, M.; Etenko, A.; Farinon, S.; Fischer, V.; Fomenko, K.; Franco, D.; Gabriele, F.; Gaffliot, J.; Galbiati, C.; Ghiano, C.; Giammarchi, M.; Goeger-Neff, M.; Goretti, A.; Gromov, M.; Hagner, C.; Houdy, T.; Hungerford, E.; Ianni, Aldo; Ianni, Andrea; Jonquàres, N.; Jedrzejczak, K.; Kaiser, M.; Kobychev, V.; Korablev, D.; Korga, G.; Kornoukhov, V.; Kryn, D.; Lachenmaier, T.; Lasserre, T.; Laubenstein, M.; Lehnert, B.; Link, J.; Litvinovich, E.; Lombardi, F.; Lombardi, P.; Ludhova, L.; Lukyanchenko, G.; Machulin, I.; Manecki, S.; Maneschg, W.; Marcocci, S.; Maricic, J.; Mention, G.; Meroni, E.; Meyer, M.; Miramonti, L.; Misiaszek, M.; Montuschi, M.; Mosteiro, P.; Muratova, V.; Musenich, R.; Neumair, B.; Oberauer, L.; Obolensky, M.; Ortica, F.; Pallavicini, M.; Papp, L.; Perasso, L.; Pocar, A.; Ranucci, G.; Razeto, A.; Re, A.; Romani, A.; Roncin, R.; Rossi, N.; Schönert, S.; Scola, L.; Semenov, D.; Skorokhvatov, M.; Smirnov, O.; Sotnikov, A.; Sukhotin, S.; Suvorov, Y.; Tartaglia, R.; Testera, G.; Thurn, J.; Toropova, M.; Veyssiére, C.; Unzhakov, E.; 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.; Borexino Collaboration

    2016-05-01

    The Borexino detector has convincingly shown its outstanding performances in the low energy regime through its accomplishments in the observation and study of the solar and geo neutrinos. It is then an ideal tool to perform a state of the art source-based experiment for testing the longstanding hypothesis of a fourth sterile neutrino with ~ eV2 mass, as suggested by several anomalies accumulated over the past three decades in source, reactor, and accelerator-based experiments. The SOX project aims at successively deploying two intense radioactive sources, made of Cerium (antineutrino) and Chromium (neutrino), respectively, in a dedicated pit located beneath the detector. The existence of such an ~ eV2 sterile neutrino would then show up as an unambiguous spatial and energy distortion in the count rate of neutrinos interacting within the active detector volume. This article reports on the latest developments about the first phase of the SOX experiment, namely CeSOX, and gives a realistic projection of CeSOX sensitivity to light sterile neutrinos in a simple (3+1) model.

  2. Probing Late Neutrino Mass Properties With SupernovaNeutrinos

    SciTech Connect

    Baker, Joseph; Goldberg, Haim; Perez, Gilad; Sarcevic, Ina

    2007-08-08

    Models of late-time neutrino mass generation contain new interactions of the cosmic background neutrinos with supernova relic neutrinos (SRNs). Exchange of an on-shell light scalar may lead to significant modification of the differential SRN flux observed at earth. We consider an Abelian U(1) model for generating neutrino masses at low scales, and show that there are cases for which the changes induced in the flux allow one to distinguish the Majorana or Dirac nature of neutrinos, as well as the type of neutrino mass hierarchy (normal or inverted or quasi-degenerate). In some region of parameter space the determination of the absolute values of the neutrino masses is also conceivable. Measurements of the presence of these effects may be possible at the next-generation water Cerenkov detectors enriched with Gadolinium, or a 100 kton liquid argon detector.

  3. Theory for Neutrino Mixing

    NASA Astrophysics Data System (ADS)

    He, Xiao-Gang

    2016-07-01

    Since the discovery of neutrino oscillations, for which Takaaki Kajita and Arthur B. McDonald were awarded the 2015 Nobel prize in physics, tremendous progresses have been made in measuring the mixing angles which determine the oscillation pattern. A lot of theoretical efforts have been made to understand how neutrinos mix with each other. Present data show that in the standard parameterization of the mixing matrix, θ23 is close to π/4 and the CP violating phase is close to - π/2. In this talk I report results obtained in arXiv:1505.01932 (Phys. Lett. B750(2015)620) and arXive:1404.01560 (Chin. J. Phys.53(2015)100101) and discuss some implications for theoretical model buildings for such mixing pattern. Specific examples for neutrino mixing based on A4 family symmetry are given.

  4. Theory for Neutrino Mixing

    NASA Astrophysics Data System (ADS)

    He, Xiao-Gang

    2016-07-01

    Since the discovery of neutrino oscillations, for which Takaaki Kajita and Arthur B. McDonald were awarded the 2015 Nobel prize in physics, tremendous progresses have been made in measuring the mixing angles which determine the oscillation pattern. A lot of theoretical efforts have been made to understand how neutrinos mix with each other. Present data show that in the standard parameterization of the mixing matrix, θ23 is close to π/4 and the CP violating phase is close to ‑ π/2. In this talk I report results obtained in arXiv:1505.01932 (Phys. Lett. B750(2015)620) and arXive:1404.01560 (Chin. J. Phys.53(2015)100101) and discuss some implications for theoretical model buildings for such mixing pattern. Specific examples for neutrino mixing based on A4 family symmetry are given.

  5. Cosmology and neutrino physics

    NASA Astrophysics Data System (ADS)

    Steigman, Gary

    1982-05-01

    Constraints on cosmology and on neutrino physics are provided by the abundances of the light elements produced during the early evolution of the universe. The predictions of primordial nucleosynthesis depend on the nucleon to photon ratio ɛ and on the number of types of two component neutrinos Nν. A comparison between the big bang predictions and the observed abundances of D, 3He, 4He and 7Li shows that ɛ is constrained to a narrow range around 4×10-10 and Nν<~4. An important consequence of the derived value of ɛ is that the universal density of nucleon is small, raising the possibility that our Universe may be dominated by massive relic neutrinos. The constraint on Nn suggests that (almost) all lepton species are now known.

  6. The Neutrino Telescope ANTARES

    NASA Astrophysics Data System (ADS)

    Hernández, Juan José

    Neutrinos can reveal a brand new Universe at high energies. The ANTARES collaboration [1] , formed in 1996, works towards the building and deployment of a neutrino telescope. This detector could observe and study high energy astrophysical sources such as X-ray binary systems, young supernova remnants or Active Galactic Nuclei and help to discover or set exclusion limits on some of the elementary particles and objects that have been put forward as candidates to fill the Universe (WIMPS, neutralinos, topological deffects, Q-balls, etc). A neutrino telescope will certainly open a new observational window and can shed light on the most energetic phenomena of the Universe. A review of the progress made by the ANTARES collaboration to achieve this goal is presented

  7. Neutrino physics: Summary talk

    SciTech Connect

    Marciano, W.J.

    1989-04-01

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

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

    SciTech Connect

    Väänänen, Daavid; Volpe, Cristina E-mail: volpe@ipno.in2p3.fr

    2011-10-01

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

  9. W.K.H. Panofsky Prize in Experimental Particle Physics Talk: 40 Years of Neutrino Physics--A Personal History

    NASA Astrophysics Data System (ADS)

    Beier, Eugene

    2010-02-01

    In the past forty years neutrino physics has made great advances. Some of the steps and missteps that were taken on the path from the 1960's to the present will be discussed. Particular attention will be given to the development of solar neutrino physics. )

  10. NOνA Neutrino Experiment

    NASA Astrophysics Data System (ADS)

    Jediny, Filip

    2015-06-01

    The NOνA experiment is a long-baseline accelerator-based neutrino oscillation experiment. It uses the upgraded NuMI beam from Fermilab and measures electron-neutrino appearance and muon-neutrino disappearance at its far detector in Ash River, Minnesota. Goals of the experiment include measurements of θ13, mass hierarchy and the CP violating phase. NOνA has begun to take neutrino data and first neutrino candidates are observed in its detectors. This document provides an overview of the scientific reach of the experiment, the status of detector operation and physics analysis, as well as the first data.

  11. Atmospheric neutrinos: Status and prospects

    NASA Astrophysics Data System (ADS)

    Choubey, Sandhya

    2016-07-01

    We present an overview of the current status of neutrino oscillation studies at atmospheric neutrino experiments. While the current data gives some tantalising hints regarding the neutrino mass hierarchy, octant of θ23 and δCP, the hints are not statistically significant. We summarise the sensitivity to these sub-dominant three-generation effects from the next-generation proposed atmospheric neutrino experiments. We next present the prospects of new physics searches such as non-standard interactions, sterile neutrinos and CPT violation studies at these experiments.

  12. Are neutrinos their own antiparticles?

    SciTech Connect

    Kayser, Boris; /Fermilab

    2009-03-01

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

  13. 7Be as a tracer of flood sedimentation on the northern California continental margin

    USGS Publications Warehouse

    Sommerfield, C. K.; Nittrouer, C. A.; Alexander, C. R.

    1999-01-01

    Sediment inventories of the cosmogenic radionuclide 7Be (t1/2=53 d) were measured on the Eel River shelf and slope (northern California continental margin) to investigate sedimentation processes associated with coastal river flooding. Seabed coring shortly after major riverflow events in 1995 and 1997 documented a shelf-wide flood deposit, and subsequent radionuclide studies determined 7Be to be a powerful tracer of fine-grained river sediment. In addition, distinctive signatures of 234Th and 210Pb were observed in oceanic flood deposits and provided additional information regarding depositional processes. During the 1995–1997 monitoring period, 7Be was present (2–35 dpm cm-2) in shelf and slope sediments only after periods of high rainfall and river runoff during the winter months. It is suggested that fluvial input was the primary source of 7Be in shelf sediments after the floods. 7Be sediment inventories and sediment-trap fluxes determined after the 1997 flood revealed that fine-grained fluvial sediments were rapidly (within one month) broadcast over the continental margin, to the 500 m isobath. Dispersal was apparently facilitated by energetic storm waves, which resuspended and redistributed some fraction of the suspended load residing on the shelf prior to accretion as flood deposits. These observations illustrate that floods are an important sedimentary process for modern environments of the Eel shelf and slope, and perhaps for other fluviomarine sedimentary systems of the northern California continental margin. Ratios of the 210Pb sediment-accumulation rate (100 yr average) to the 7Be deposition rate (1–2 month average) for shelf sites illustrate the episodic nature of shelf sedimentation, and suggest that a minimum of 3–30 depositional events complete the most recent stratigraphic record. This observation is consistent with the magnetude and frequency of fluvial sediment input, as Eel River floods with return periods of 3–33 yr (3% of the time of

  14. Effects of Recent Reactor Anti-neutrino Spectra on Neutrino Oscillations

    NASA Astrophysics Data System (ADS)

    Sterbenz, Ciara

    2015-10-01

    The β-decay of nuclear fission fragments produces a very large ve flux from nuclear reactions. The shape of the expected flux has previously been predicted by converting the measured β-electron spectrum to an ve spectrum. Recent reactor neutrino experiments, however, find a large shoulder in the observed ve spectrum relative to this prediction in the energy region 5 - 7 MeV. Accurate knowledge of the expected ve flux from reactors is important for oscillation experiments that only involve one neutrino detector. In this project, I examine the implications of these spectral changes on the ν oscillation result found by the KamLAND experiment. At the time of their finding, the spectral anomaly from 5 - 7 MeV had not be observed. I have re-derived the oscillation parameters Δm2 and sin2 (2 θ) using the anti-neutrino flux from Daya Bay and from nuclear database predictions. With these new expected fluxes, these oscillation parameters shifted and their uncertainties increased. I compare the new oscillation parameters with those derived from solar neutrino oscillation data.

  15. Supernova heavy element nucleosynthesis: Can it tell us about neutrino masses?

    SciTech Connect

    Fuller, George M.

    1997-05-20

    Here we describe a new probe of neutrino properties based on heavy element nucleosynthesis. This technique is in many ways akin to the familiar light element Primordial Nucleosynthesis probe of conditions in the early universe. Our new probe is based on the fact that neutrino masses and vacuum mixings can engender matter-enhanced neutrino flavor transformation in the post core bounce supernova environment. Transformations of the type {nu}{sub {mu}}{sub (r)}<-->{nu}{sub e} in this site will have significant effects on the synthesis of the rapid neutron capture (r-Process) elements and the light p-nuclei. We suggest that an understanding of the origin of these nuclides, combined with the measured abundances of these species, may provide a ''Rosetta Stone'' for neutrino properties. Heavy element nucleosynthesis abundance considerations give either constraints/evidence for neutrino masses and flavor mixings, or strong constraints on the site of origin of r-Process nucleosynthesis. The putative limits on neutrino characteristics are complimentary to those derived from laboratory neutrino oscillation studies and solar and atmospheric neutrino experiments. Preliminary studies show that the existence of r-Process nuclei in the abundances observed in the Galaxy cannot be understood unless neutrinos have small masses (possibly in the cosmologically significant range)

  16. W. K. H. Panofsky Prize: The Road to Neutrino Mixing Angle θ13

    NASA Astrophysics Data System (ADS)

    Luk, Kam-Biu

    2014-03-01

    A series of solar, atmospheric, accelerator and reactor neutrino experiments have observed transformations of one type of neutrino to another type. This intriguing phenomenon called neutrino oscillation was predicted by Pontecorvo, Maki, Nakagawa and Sakata. It is due to the fact that the three flavors of neutrinos observed in laboratories are mixtures of three neutrino mass eigenstates. Neutrino mixing is described by a set of three mixing angles and a CP-violating phase. The smallest angle, θ13, was unknown until 2012. Knowing the value of θ13 is essential. Besides being a fundamental parameter of nature, knowing its value will improve our understanding of neutrino mixing, provide guidance for building theoretical models and define the future program of neutrino oscillation experiments. In this talk, the experimental development that led to the recent discovery of a new θ13-driven neutrino oscillation will be presented. Work was supported by the US Department of Energy, Office of High Energy Physics, contract DE-AC02-05CH11231.

  17. Sterile Neutrino Search with MINOS

    SciTech Connect

    Devan, Alena V.

    2015-08-01

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

  18. Activity size distribution and residence time of 7Be aerosols in the Arctic atmosphere

    NASA Astrophysics Data System (ADS)

    Ioannidou, Alexandra; Paatero, Jussi

    2014-05-01

    The activity size distributions of the natural radionuclide tracer 7Be in different size range fractions (<0.39 μm, 0.39-0.69 μm, 0.69-1.3 μm, 1.3-2.1 μm, 2.1-4.2 μm, 4.2-10.2 μm and >10.2 μm) were determined in the boreal atmosphere in the Arctic Research Centre of the Finnish Meteorological Institute (FMI) at Sodankylä, Finland (67°22‧ N, 26°38‧ E, 180 m asl). The activity median aerodynamic diameter (AMAD) ranged from 0.54 μm to 1.05 μm (average 0.83 μm). A residence time of about 8 days applies to aerosols of 0.83 μm diameter, representing the residence of aerosol particles in arctic environment. The observed positive correlation between AMAD values and RH% can be explained by the fact that condensation during high relative humidity conditions becomes more intense, resulting in increased particle sizes of atmospheric aerosols. However, greater aerosol particle sizes means higher wet scavenging rate of aerosols and as a result lower activity concentration of 7Be in the atmosphere, explaining the anti-correlation between the AMAD values and activity concentrations of 7Be. But this associated with possibly higher scavenging rates of aerosols does not necessarily alone explain the anti-correlation between the AMAD and the 7Be activities. The air mass origin associated with synoptic scale weather phenomena may contribute to that too. The Flextra model was used to assess the transport pattern and to explain the deviation in radionuclide activity concentrations and AMAD values observed in the site of investigation.

  19. Exploring Light Neutron Rich Nuclei via the ({sup 7}Li,{sup 7}Be) Reaction

    SciTech Connect

    Cavallaro, M.; Cappuzzello, F.; Cunsolo, A.; Foti, A.; Orrigo, S. E. A.; Rodrigues, M. R. D.; Borello-Lewin, T.; Lenske, H.; Petrascu, H.; Winfield, J. S.

    2008-11-11

    A systematic study of the nuclei that can be described as an integer number of {alpha} particles plus three neutrons via the ({sup 7}Li,{sup 7}Be) reaction at about 8 MeV/u has shown the presence of Bound States Embedded in the Continuum in the energy spectra. These are experimental signatures of the dynamical correlations of an easily polarizable core with a single-particle state of the valence neutron.

  20. Seasonal 7Be and 137Cs activities in surface air before and after the Chernobyl event.

    PubMed

    Kulan, A

    2006-01-01

    Seasonal fluctuations of cosmogenic (7)Be (T(1/2)=53.4 days) and anthropogenic (137)Cs (T(1/2)=30 years) activities in surface air (aerosols) have been extracted from a long data record (1972-2000) at high latitude (56 degrees N-68 degrees N, Sweden). Normalization to weekly average values was used to control long-term trends so that cyclical trends could be investigated. Enhanced (7)Be activity was observed in spring and summer seasons and likely relates to the seasonal thinning of the tropopause. Variations in the (137)Cs activity record seem to reflect how the isotope was injected in the atmosphere (stratospheric from bomb tests and tropospheric from the Chernobyl accident) and subsequent transport mechanisms. Accordingly, until 1986, the surface air (137)Cs activity was strongly related to nuclear weapons test fallout and exhibits temporal fluctuations resembling the (7)Be. Conversely, since 1986 the Chernobyl-produced (137)Cs dominates the long-term record that shows annual cycles that are strongly controlled by atmospheric boundary layer conditions. Additionally, short-term data within the post-Chernobyl period suggest subtle intrusion of air masses rich in (137)Cs that may occur throughout the year, and differences resulting from spatial occurrence at these latitudes. This is an important observation that may have to do with year-to-year variation and calls for caution when interpreting short-term data records. PMID:16876295

  1. Evaluating physical and biological influences on sedimentation in a tidal freshwater marsh with 7Be

    NASA Astrophysics Data System (ADS)

    Palinkas, Cindy M.; Engelhardt, Katharina A. M.; Cadol, Dan

    2013-09-01

    Key differences exist between tidal fresh- and saltwater marshes, such as the relative importance of mineral versus organic sedimentation and plant species diversity, that likely result in different drivers of sedimentation. In tidal freshwater marshes, we hypothesize that vegetation composition, along with physical marsh features (i.e., elevation and tidal channels), play a critical role in sedimentation. This hypothesis is evaluated in Dyke Marsh Preserve (Potomac River, VA, USA) by examining sediment character (grain size, organic content) and deposition rates across the marsh in spring and summer 2010 and 2011. 7Be is especially well suited to capture seasonal sedimentation patterns owing to its short half-life (53.3 d) and ability to assess both sediment deposition and erosion. However, its use in marshes can be challenging, especially due the presence of vegetation. In this study, 7Be-derived sedimentation rates are compared with sediment deposition observed on ceramic tiles to assess its utility in tidal freshwater marshes, and biophysical influences on sediment deposition are examined through statistical models. 7Be- and tile-derived sedimentation rates show similar spatial and temporal patterns, with highest rates occurring at sites closer to tidal channels, highlighting the importance of sediment availability. In addition, complex feedbacks between sedimentation and the plant community are discussed.

  2. Stopping power of neutrinos and antineutrinos in polymers

    NASA Technical Reports Server (NTRS)

    Rustgi, M. L.; Leung, P. T.; Long, S. A. T.

    1985-01-01

    The Weinberg-Salam model is applied to quantify the energy loss of antineutrinos and neutrinos encountering polymers. The scattering cross-sectional energy due to encounters with electrons is calculated, along with the probability that an antineutrino will remain the same particle. The energy loss reaches a maximum, i.e., stopping occurs, when the probability is unity. The technique is applied to study the energy losses in kapton, a solid organic insulator used for antennas on spacecraft exposed to solar neutrinos with energies ranging from 0.5-10 MeV. The energy loss is found to be negligible.

  3. Next discoveries in neutrino mixing: Electron neutrino appearance

    NASA Astrophysics Data System (ADS)

    Duyang, Hongyue

    The discovery of neutrino oscillation is a clear evidence of new physics beyond the Standard Model. Measurements of electron neutrino (nu e) and electron anti-neutrino (nu e) appearances are the most important channels to complete the neutrino mixing matrix. In a nue/ nue appearance experiment, a near detector (ND) is used to constrain the neutrino flux and measure the backgrounds to the signal. Backgrounds to the nue appearance comes from Neutral Current Muon Neutrino Interactions (numu-NC), Charged Current Muon Neutrino Interactions (numu-CC), beam nu e events and outside backgrounds. The background components are then extrapolated to the far detector (FD). By looking for excess of signal nu e/nue-like events in FD, we measure the neutrino mixing angle, neutrino's mass hierarchy and the elusive CP-violation in the lepton sector. This dissertation focuses on the signals and backgrounds in nu e/nue appearance measurements. The first part of the dissertation presents an analysis of nue appearance in a large Water Cherenkov detector such as the one proposed by the LBNE collaboration. The analysis, including scanning thousands of events, aims to distinguish nu e signals from the NC backgrounds. The second part of the dissertation presents measurements of Resonance Neutrino Interactions using the NOMAD data. This process plays a critical role in not only neutrino-nuclear cross section but also in the precision analysis of the next generation of neutrino oscillation experiments such as NOnuA and LBNE. The last part of the dissertation discusses the method of using low-nu fit method to measure relative neutrino flux and constrain beam nue background.

  4. Reactor mixing angle from hybrid neutrino masses

    NASA Astrophysics Data System (ADS)

    Sierra, D. Aristizabal; de Medeiros Varzielas, I.

    2014-07-01

    In terms of its eigenvector decomposition, the neutrino mass matrix (in the basis where the charged lepton mass matrix is diagonal) can be understood as originating from a tribimaximal dominant structure with small deviations, as demanded by data. If neutrino masses originate from at least two different mechanisms, referred to as "hybrid neutrino masses", the experimentally observed structure naturally emerges provided one mechanism accounts for the dominant tribimaximal structure while the other is responsible for the deviations. We demonstrate the feasibility of this picture in a fairly model-independent way by using lepton-number-violating effective operators, whose structure we assume becomes dictated by an underlying A 4 flavor symmetry. We show that if a second mechanism is at work, the requirement of generating a reactor angle within its experimental range always fixes the solar and atmospheric angles in agreement with data, in contrast to the case where the deviations are induced by next-to-leading order effective operators. We prove this idea is viable by constructing an A 4-based ultraviolet completion, where the dominant tribimaximal structure arises from the type-I seesaw while the subleading contribution is determined by either type-II or type-III seesaw driven by a non-trivial A 4 singlet (minimal hybrid model). After finding general criteria, we identify all the N symmetries capable of producing such A 4-based minimal hybrid models.

  5. The enriched chromium neutrino source for GALLEX

    SciTech Connect

    Hartmann, F.X.; Hahn, R.L.

    1991-01-18

    The preparation and study of an intense source of neutrinos in the form of neutron irradiated materials which are enriched in Cr-50 for use in the GALLEX solar neutrino experiment are discussed. Chromyl fluoride gas is enriched in the Cr-50 isotope by gas centrifugation and subsequently converted to a very stable form of chromium oxide. The results of neutron activation analyses of such chromium samples indicate low levels of any long-lived activities, but show that short-lived activities, in particular Na-24, may be of concern. These results show that irradiating chromium oxide enriched in Cr-50 is preferable to irradiating either natural chromium or argon gas as a means of producing a neutrino source to calibrate the GALLEX detector. These results of the impurity level analysis of the enriched chromyl fluoride gas and its conversion to the oxide are also of interest to work in progress by other members of the Collaboration investigating an alternative conversion of the enriched gas to chromium metal. 35 refs., 12 figs., 5 tabs.

  6. The neutrino electron accelerator

    SciTech Connect

    Shukla, P.K.; Stenflo, L.; Bingham, R.; Bethe, H.A.; Dawson, J.M.; Mendonca, J.T.

    1998-01-01

    It is shown that a wake of electron plasma oscillations can be created by the nonlinear ponderomotive force of an intense neutrino flux. The electrons trapped in the plasma wakefield will be accelerated to high energies. Such processes may be important in supernovas and pulsars. {copyright} {ital 1998 American Institute of Physics.}

  7. Long Baseline Neutrino Experiments

    NASA Astrophysics Data System (ADS)

    Mezzetto, Mauro

    2016-05-01

    Following the discovery of neutrino oscillations by the Super-Kamiokande collaboration, recently awarded with the Nobel Prize, two generations of long baseline experiments had been setup to further study neutrino oscillations. The first generation experiments, K2K in Japan, Minos in the States and Opera in Europe, focused in confirming the Super-Kamiokande result, improving the precision with which oscillation parameters had been measured and demonstrating the ντ appearance process. Second generation experiments, T2K in Japan and very recently NOνA in the States, went further, being optimized to look for genuine three neutrino phenomena like non-zero values of θ13 and first glimpses to leptonic CP violation (LCPV) and neutrino mass ordering (NMO). The discovery of leptonic CP violation will require third generation setups, at the moment two strong proposals are ongoing, Dune in the States and Hyper-Kamiokande in Japan. This review will focus a little more in these future initiatives.

  8. Atmospheric deposition of {sup 7}Be by rain events, incentral Argentina

    SciTech Connect

    Ayub, J. Juri; Velasco, H.; Rizzotto, M.; Di Gregorio, D. E.; Huck, H.

    2008-08-07

    Beryllium-7 is a natural radionuclide that enters into the ecosystems through wet and dry depositions and has numerous environmental applications in terrestrial and aquatic ecosystems. Atmospheric wet deposition of {sup 7}Be was measured in central Argentina. Rain traps were installed (1 m above ground) and individual rain events have been collected. Rain samples were filtered and analyzed by gamma spectrometry. The gamma counting was undertaken using a 40%-efficient p-type coaxial intrinsic high-purity natural germanium crystal built by Princeton Gamma-Tech. The cryostat was made from electroformed high-purity copper using ultralow-background technology. The detector was surrounded by 50 cm of lead bricks to provide shielding against radioactive background. The detector gamma efficiency was determined using a water solution with known amounts of chemical compounds containing long-lived naturally occurring radioisotopes, {sup 176}Lu, {sup 138}La and {sup 40}K. Due to the geometry of the sample and its position close to the detector, the efficiency points from the {sup 176}Lu decay, had to be corrected for summing effects. The measured samples were 400 ml in size and were counted curing one day. The {sup 7}Be detection limit for the present measurements was as low as 0.2 Bq l{sup -1}. Thirty two rain events were sampled and analyzed (November 2006-May 2007). The measured values show that the events corresponding to low rainfall (<20 mm) are characterized by significantly higher activity concentrations (Bq l{sup -1}). The activity concentration of each individual event varied from 0.8 to 3.5 Bq l{sup -1}, while precipitations varied between 4 and 70 mm. The integrated activity by event of {sup 7}Be was fitted with a model that takes into account the precipitation amount and the elapsed time between two rain events. The integrated activities calculated with this model show a good agreement with experimental values.

  9. A non-standard CP transformation leading to maximal atmospheric neutrino mixing

    NASA Astrophysics Data System (ADS)

    Grimus, Walter; Lavoura, Luís.

    2004-01-01

    We discuss a neutrino mass matrix Mν originally found by Babu, Ma, and Valle (BMV) and show that this mass matrix can be characterized by a simple algebraic relation. From this relation it follows that atmospheric neutrino mixing is exactly maximal while at the same time an arbitrary mixing angle θ13 of the lepton mixing matrix U is allowed and—in the usual phase convention—CP violation in mixing is maximal; moreover, neither the neutrino mass spectrum nor the solar mixing angle are restricted. We put forward a seesaw extension of the Standard Model, with three right-handed neutrinos and three Higgs doublets, where the family lepton numbers are softly broken by the Majorana mass terms of the right-handed neutrino singlets and the BMV mass matrix results from a non-standard CP symmetry.

  10. SNO+ status and plans for double beta decay search and other neutrino studies

    NASA Astrophysics Data System (ADS)

    Andringa, S.; SNO+ Collaboration

    2016-01-01

    SNO+ is a multi-purpose Neutrino Physics experiment, succeeding to the Sudbury Neutrino Observatory by replacing heavy water with liquid scintillator, which can also be loaded with large quantities of double-beta decaying isotope. The scientific goals of SNO+ are the search for neutrinoless double-beta decay, the study of solar neutrinos and of anti-neutrinos from nuclear reactors and the Earth's natural radioactivity, as well as supernovae neutrinos. The installation of the detector at SNOLAB is being completed and commissioning has already started with a dry run. The detector will soon be filled with water and, later, with scintillator. Here we highlight the main detector developments and address the several Physics analysis being prepared for the several planned SNO+ runs.

  11. Using 7Be measurements to estimate the relative contributions of interrill and rill erosion

    NASA Astrophysics Data System (ADS)

    Zhang, Feng-Bao; Yang, Ming-Yi; Walling, Des E.; Zhang, Bo

    2014-02-01

    Rapid and reliable methods for estimating the relative contribution of interrill and rill erosion during a rainfall event are needed to provide an improved understanding of soil erosion processes and to develop process-based soil erosion prediction models. Use of the radionuclide 7Be in controlled experiments provides a means of addressing this need and this paper reports an experimental study aimed at refining and testing procedures employed to estimate the relative contribution of the two components of erosion. Four experimental plots (area 5 × 2 m and 10°, 15°, 20°, and 25° slope), filled with a loessial soil, manually tilled, and kept free of weeds with herbicides, were subjected to high intensity rainfall (91.8-120.6 mm h- 1), in order to induce rill development. The evolution of the rill network was documented photographically during the rainfall events and the runoff and sediment output from the plots were collected and measured. The sediment was recovered from the runoff and its mass and 7Be activity were measured. The Yang model, reported previously, was used to estimate the relative contributions of interrill and rill erosion from the 7Be activity of the exported sediment and this model was further refined to take account of the dynamic growth of the rills during the rainfall event. The results from the experiments were also used to develop a simple empirical linear model for estimating the relative contributions of interrill and rill erosion from the 7Be measurements. A comparison of the results provided by the three models showed some differences in the estimates of the magnitude of the relative contributions, although their trend during the event was similar. The estimates provided by the empirical linear model tended to be higher than those obtained using the refined model and lower than those generated by the Yang model, but were closer to those provided by the refined model which was seen as being theoretically the most accurate model. The

  12. Beam shaping assembly optimization for (7)Li(p,n)(7)Be accelerator based BNCT.

    PubMed

    Minsky, D M; Kreiner, A J

    2014-06-01

    Within the framework of accelerator-based BNCT, a project to develop a folded Tandem-ElectroStatic-Quadrupole accelerator is under way at the Atomic Energy Commission of Argentina. The proposed accelerator is conceived to deliver a proton beam of 30mA at about 2.5MeV. In this work we explore a Beam Shaping Assembly (BSA) design based on the (7)Li(p,n)(7)Be neutron production reaction to obtain neutron beams to treat deep seated tumors.

  13. Beam shaping assembly optimization for (7)Li(p,n)(7)Be accelerator based BNCT.

    PubMed

    Minsky, D M; Kreiner, A J

    2014-06-01

    Within the framework of accelerator-based BNCT, a project to develop a folded Tandem-ElectroStatic-Quadrupole accelerator is under way at the Atomic Energy Commission of Argentina. The proposed accelerator is conceived to deliver a proton beam of 30mA at about 2.5MeV. In this work we explore a Beam Shaping Assembly (BSA) design based on the (7)Li(p,n)(7)Be neutron production reaction to obtain neutron beams to treat deep seated tumors. PMID:24345525

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

    PubMed

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

    2004-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2012-08-01

    The data taken with the ANTARES neutrino telescope from 2007 to 2010, a total live time of 863 days, are used to measure the oscillation parameters of atmospheric neutrinos. Muon tracks are reconstructed with energies as low as 20 GeV. Neutrino oscillations will cause a suppression of vertical upgoing muon neutrinos of such energies crossing the Earth. The parameters determining the oscillation of atmospheric neutrinos are extracted by fitting the event rate as a function of the ratio of the estimated neutrino energy and reconstructed flight path through the Earth. Measurement contours of the oscillation parameters in a two-flavour approximation are derived. Assuming maximal mixing, a mass difference of Δ m322 = (3.1 ± 0.9) ṡ10-3eV2 is obtained, in good agreement with the world average value.

  16. Leptonic CP Violation measurement at the neutrino factory

    NASA Astrophysics Data System (ADS)

    Burguet Castell, J.; Mena, O.

    2003-05-01

    In this talk, based on the work [J. Burguet Castell, et al., Nucl. Phys. B 608 (2001) 301], we refine our previous analysis [A. Cervera, et al., Nucl. Phys. B 579 (2000) 17] of the sensitivity to leptonic CP violation and θ13 at a neutrino factory in the LMA-MSW scenario, by exploring the full range of these two parameters. We have discovered that there exist, at fixed neutrino energy, Eν, and baseline, L, degenerate solutions. Although the spectral analysis helps in disentangling fake from true solutions, a leftover product of this degeneracy remains for a realistic detector, which we analyse. Furthermore, we take into account the expected uncertainties on the solar and atmospheric oscillation parameters and in the average Earth matter density along the neutrino path. An intermediate baseline of O(3000) km is still the best option to tackle CP violation, although a combination of two baselines turns out to be very important in resolving degeneracies.

  17. Three-Neutrino Oscillation Parameters: Status and Prospects

    NASA Astrophysics Data System (ADS)

    Capozzi, F.; Fogli, G. L.; Lisi, E.; Marrone, A.; Montanino, D.; Palazzo, A.

    Neutrino oscillation searches using a variety of sources (solar, atmospheric, accelerator and reactor neutrinos) have established a standard three-neutrino (3ν) mass-mixing framework and five of its parameters: the two squared mass gaps (δm2, Δm2) and the three mixing angles (θ12, θ13, θ23). At present, a single class of experiments dominates each of these parameters, while only combined analyses of various (eventually all) data sets are needed to constrain the still unknown mass hierarchy [sign(Δm2)], θ23 octant and CP-violating phase δ. We review the status of the known and unknown parameters (as emerging from a global analysis of the oscillation data), investigate the correlations and stability of the such parameters within different combinations of data sets, and discuss the near-term prospects in this field.

  18. Neutrino nucleosynthesis in core-collapse Supernova explosions

    NASA Astrophysics Data System (ADS)

    Sieverding, A.; Huther, L.; Martínez-Pinedo, G.; Langanke, K.; Heger, A.

    2016-02-01

    The neutrino-induced nucleosynthesis (ν process) in supernova explosions of massive stars of solar metallicity with initial main sequence masses between 15 and 40 M⊙ has been studied. A new extensive set of neutrino-nucleus cross-sections for all the nuclei included in the reaction network is used and the average neutrino energies are reduced to agree with modern supernova simulations. Despite these changes the ν process is found to contribute still significantly to the production of the nuclei 7Li, 11B, 19F, 138La and 180Ta, even though the total yields for those nuclei are reduced. Furthermore we study in detail contributions of the ν process to the production of radioactive isotopes 26Al, 22Na and confirm the production of 92Nb and 98Tc.

  19. Neutrino magnetic moment effects in neutrino nucleus reactions

    SciTech Connect

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

    1995-10-01

    Some low energy neutrino nucleus reactions induced by neutrinos (antineutrinos) having a magnetic moment of the order of 10{sup {minus}9}{minus}10{sup {minus}10} Bohr magneton are studied. It is found that in the case of {sup 4}He, {sup 12}C, and {sup 16}O, the detection of very low energy scalar and isoscalar elastic and inelastic reactions induced by the isoscalar vector currents can provide a better limit on the neutrino magnetic moment.

  20. On the Detection of the Free Neutrino

    DOE R&D Accomplishments Database

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

    1953-08-06

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

  1. Brief introduction of the neutrino event generators

    SciTech Connect

    Hayato, Yoshinari

    2015-05-15

    The neutrino interaction simulation programs (event generators) play an important role in the neutrino experiments. This article briefly explains what is the neutrino event generator and how it works.

  2. A new study of 10B(p,α)7Be reaction at low energies

    NASA Astrophysics Data System (ADS)

    Caciolli, A.; Depalo, R.; Broggini, C.; La Cognata, M.; Lamia, L.; Menegazzo, R.; Mou, L.; Puglia, S. M. R.; Rigato, V.; Romano, S.; Rossi Alvarez, C.; Sergi, M. L.; Spitaleri, C.; Tumino, A.

    2016-05-01

    The 10B(p,α)7Be reaction is of great interest since it has many applications in different fields of research such as nuclear astrophysics, nuclear physics, and models of new reactors for clean energy generation. This reaction has been studied at the AN2000 accelerator of the INFN National Laboratories of Legnaro (LNL). The total cross section has been measured in a wide energy range (250-1182 keV) by using the activation method. The decays of the 7Be nuclei produced by the reaction were measured at the low counting facility of LNL by using two fully shielded high-purity germanium detectors. The present dataset shows a large discrepancy with respect to one of the previous data at the same energies and reduces the total uncertainty to the level of 6%. An R-matrix calculation has been performed on the present data using the parameters from previous Trojan Horse measurements for the 10 and 500keV resonances. The present data do not lay on the R-matrix fit in one point suggesting the existence of a 11C level not observed yet. Further nuclear investigations are needed to confirm this hypothesis.

  3. Evaluating uncertainty in 7Be-based soil erosion estimates: an experimental plot approach

    NASA Astrophysics Data System (ADS)

    Blake, Will; Taylor, Alex; Abdelli, Wahid; Gaspar, Leticia; Barri, Bashar Al; Ryken, Nick; Mabit, Lionel

    2014-05-01

    Soil erosion remains a major concern for the international community and there is a growing need to improve the sustainability of agriculture to support future food security. High resolution soil erosion data are a fundamental requirement for underpinning soil conservation and management strategies but representative data on soil erosion rates are difficult to achieve by conventional means without interfering with farming practice and hence compromising the representativeness of results. Fallout radionuclide (FRN) tracer technology offers a solution since FRN tracers are delivered to the soil surface by natural processes and, where irreversible binding can be demonstrated, redistributed in association with soil particles. While much work has demonstrated the potential of short-lived 7Be (half-life 53 days), particularly in quantification of short-term inter-rill erosion, less attention has focussed on sources of uncertainty in derived erosion measurements and sampling strategies to minimise these. This poster outlines and discusses potential sources of uncertainty in 7Be-based soil erosion estimates and the experimental design considerations taken to quantify these in the context of a plot-scale validation experiment. Traditionally, gamma counting statistics have been the main element of uncertainty propagated and reported but recent work has shown that other factors may be more important such as: (i) spatial variability in the relaxation mass depth that describes the shape of the 7Be depth distribution for an uneroded point; (ii) spatial variability in fallout (linked to rainfall patterns and shadowing) over both reference site and plot; (iii) particle size sorting effects; (iv) preferential mobility of fallout over active runoff contributing areas. To explore these aspects in more detail, a plot of 4 x 35 m was ploughed and tilled to create a bare, sloped soil surface at the beginning of winter 2013/2014 in southwest UK. The lower edge of the plot was bounded by

  4. Revisiting the standard solar model

    SciTech Connect

    Turck-Chieze, S.; Cahen, S.; Casse, M.; Doom, C.

    1988-12-01

    The mutual consistency between standard solar models is studied based on the recent Los Alamos opacity tables. Satisfactory agreement is found among these models concerning the helium content and the neutrino capture rates. The reference model leads to a solar helium content of 0.276 + or - 0.012 by mass fraction. 75 references.

  5. Unparticle physics and neutrino phenomenology

    SciTech Connect

    Barranco, J.; Bolanos, A.; Miranda, O. G.; Moura, C. A.; Rashba, T. I.

    2009-04-01

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

  6. EDITORIAL: The 2nd Scandinavian NeutrinO Workshop

    NASA Astrophysics Data System (ADS)

    2006-10-01

    The first Scandinavian NeutrinO Workshop (SNOW) was held in Uppsala, Sweden, in February 2001. About five years passed until the next SNOW took place—this time in Stockholm, Sweden between 2 May 2006 and 6 May 2006. The aim of the workshop was to cover a variety of topics in neutrino physics with leading researchers in the field as speakers. The Royal Swedish Academy of Sciences (KVA) awarded SNOW 2006 a grant for inviting such speakers. The workshop was mainly directed towards phenomenology and theory with connections to experiments and gave an opportunity for theorists and experimentalists to work together, discuss the latest results, and combine the different branches of neutrino physics. The different topics discussed were: solar and atmospheric neutrinos, reactor and accelerator neutrinos, neutrinos in astrophysics and cosmology, phenomenology of neutrino data, neutrino oscillations, theory and model building, fundamental properties of neutrinos, neutrinoless double beta decay, and flavor physics. Around 70 scientists (spanning from graduate students to world-leading researchers) in the field of neutrino physics participated in SNOW 2006 and 44 talks were presented in plenary sessions. Out of the 44 talks, 37 have been contributed to these proceedings. The talks of SNOW 2006 took place in the Oskar Klein Auditorium at the AlbaNova University Center in Stockholm. The AlbaNova University Center is a joint endeavour between the Royal Institute of Technology (KTH) and Stockholm University. The social program included a welcome reception at KVA, an excursion to the Royal Armoury at the Royal Palace in Stockholm as well as a boat trip in the archipelago of Stockholm, a reception at the City Hall of Stockholm arranged by the city, and finally, a workshop dinner at Häringe Castle south of Stockholm. T Ohlsson and M Blennow Royal Institute of Technology (KTH), Stockholm, Sweden B Badelek Uppsala University, Uppsala, Sweden J Edsjö Stockholm University, Stockholm

  7. Muon Colliders and Neutrino Factories *

    NASA Astrophysics Data System (ADS)

    Geer, Steve

    2009-11-01

    Over the past decade, there has been significant progress in developing the concepts and technologies needed to produce, capture, and accelerate O(1021) muons per year. These developments have paved the way for a new type of neutrino source (neutrino factory) and a new type of very high energy lepton-antilepton collider (muon collider). This article reviews the motivation, design, and research and development for future neutrino factories and muon colliders.

  8. Muon Colliders and Neutrino Factories

    SciTech Connect

    Geer, Steve; /Fermilab

    2009-11-01

    Over the past decade, there has been significant progress in developing the concepts and technologies needed to produce, capture, and accelerate {Omicron}(10{sup 21}) muons per year. These developments have paved the way for a new type of neutrino source (neutrino factory) and a new type of very high energy lepton-antilepton collider (muon collider). This article reviews the motivation, design, and research and development for future neutrino factories and muon colliders.

  9. Neutrinos in astrophysics and cosmology

    NASA Astrophysics Data System (ADS)

    Balantekin, A. B.

    2016-06-01

    Neutrinos play a crucial role in many aspects of astrophysics and cosmology. Since they control the electron fraction, or equivalently neutron-to-proton ratio, neutrino properties impact yields of r-process nucleosynthesis. Similarly the weak decoupling temperature in the Big Bang Nucleosynthesis epoch is exponentially dependent on the neutron-to-proton ratio. In these conference proceedings, I briefly summarize some of the recent work exploring the role of neutrinos in astrophysics and cosmology.

  10. Neutrino Masses and Flavor Oscillations

    NASA Astrophysics Data System (ADS)

    Wang, Yifang; Xing, Zhi-Zhong

    2016-10-01

    This essay is intended to provide a brief description of the peculiar properties of neutrinos within and beyond the standard theory of weak interactions. The focus is on the flavor oscillations of massive neutrinos, from which one has achieved some striking knowledge about their mass spectrum and flavor mixing pattern. The experimental prospects towards probing the absolute neutrino mass scale, possible Majorana nature and CP-violating effects, will also be addressed.

  11. Neutrino Oscillograms of the Earth

    SciTech Connect

    Smirnov, Alexei Yu.

    2008-04-16

    Oscillograms are 'neutrino portraits' of the Earth. They encode unique information about the Earth interior and provide a comprehensive description of neutrino oscillation phenomena. I will explain the physical effects involved and the structure of the oscillograms. Dependence of the oscillograms on neutrino parameters, in particular, on the currently unknown q1-3, mixing and CP-violation phase will be considered. A program of measurements of the oscillograms will be outlined.

  12. Muon colliders and neutrino factories

    SciTech Connect

    Geer, S.; /Fermilab

    2010-09-01

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

  13. Astrophysical and cosmological constraints to neutrino properties

    NASA Technical Reports Server (NTRS)

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

    1989-01-01

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

  14. (7)Be, (210)Pb, and (210)Po in the surface air from the Arctic to Antarctica.

    PubMed

    Persson, Bertil R R; Holm, Elis

    2014-12-01

    In the present study we have investigated the activity concentrations of (210)Pb, (210)Po as well as (7)Be in surface air of the North and South Atlantic (1988-1989), the Arctic Ocean (1991), and along the coastline of Siberia (1994) during succeeding expeditions in the Swedish Polar Research program. During the cruises in the Arctic Ocean during 1991-07-28 to 1991-10-04 the average air concentrations of (7)Be was 0.6 ± 0.4 mBq/m(3), (210)Pb 40 ± 4 μBq/m(3) and (210)Po-38 ± 10 μBq/m(3). During the Swedish-Russian Tundra Ecology-94 expedition along the Siberian coastline the average air concentrations of (7)Be and (210)Pb measured during May-July were 11 ± 3, and 2.4 ± 0.4 mBq/m(3), and during July-September they were 7.2 ± 2 and 2.7 ± 1.1 mBq/m(3) respectively. The results from measurements of the activity concentration of (210)Pb in the air over the Arctic Ocean vary between 75 and 176 μBq/m(3). In the air close to land masses, however, the activity concentration of (210)Pb in the air increases to 269-2712 μBq/m(3). The activity concentration of (7)Be in the South Atlantic during the cruise down to Antarctica varied between 1.3 and 1.7 with an average of 1.5 ± 0.8 mBq/m(3). The activity concentration of (210)Pb in the South Atlantic down to Antarctica varied between 6 and 14 μBq/m(3). At the Equator the activity concentration recorded in November 1988 was 630 μBq/m(3) and in April 1989 it was 260 μBq/m(3). The average activity concentration of (210)Pb during the route Gothenburg-Montevideo in 1988 was 290 and on the return Montevideo-Gothenburg it was 230 μBq/m(3). The activity concentration of (210)Po in the South Atlantic down to Antarctica varied between 15 and 58 μBq/m(3). At the Equator the activity concentration in November 1988 was 170 and in April 1989 it was 70 μBq/m(3). The average activity concentration of (210)Po during the route Gothenburg-Montevideo in 1988 was 63 and on the return Montevideo

  15. (7)Be, (210)Pb, and (210)Po in the surface air from the Arctic to Antarctica.

    PubMed

    Persson, Bertil R R; Holm, Elis

    2014-12-01

    In the present study we have investigated the activity concentrations of (210)Pb, (210)Po as well as (7)Be in surface air of the North and South Atlantic (1988-1989), the Arctic Ocean (1991), and along the coastline of Siberia (1994) during succeeding expeditions in the Swedish Polar Research program. During the cruises in the Arctic Ocean during 1991-07-28 to 1991-10-04 the average air concentrations of (7)Be was 0.6 ± 0.4 mBq/m(3), (210)Pb 40 ± 4 μBq/m(3) and (210)Po-38 ± 10 μBq/m(3). During the Swedish-Russian Tundra Ecology-94 expedition along the Siberian coastline the average air concentrations of (7)Be and (210)Pb measured during May-July were 11 ± 3, and 2.4 ± 0.4 mBq/m(3), and during July-September they were 7.2 ± 2 and 2.7 ± 1.1 mBq/m(3) respectively. The results from measurements of the activity concentration of (210)Pb in the air over the Arctic Ocean vary between 75 and 176 μBq/m(3). In the air close to land masses, however, the activity concentration of (210)Pb in the air increases to 269-2712 μBq/m(3). The activity concentration of (7)Be in the South Atlantic during the cruise down to Antarctica varied between 1.3 and 1.7 with an average of 1.5 ± 0.8 mBq/m(3). The activity concentration of (210)Pb in the South Atlantic down to Antarctica varied between 6 and 14 μBq/m(3). At the Equator the activity concentration recorded in November 1988 was 630 μBq/m(3) and in April 1989 it was 260 μBq/m(3). The average activity concentration of (210)Pb during the route Gothenburg-Montevideo in 1988 was 290 and on the return Montevideo-Gothenburg it was 230 μBq/m(3). The activity concentration of (210)Po in the South Atlantic down to Antarctica varied between 15 and 58 μBq/m(3). At the Equator the activity concentration in November 1988 was 170 and in April 1989 it was 70 μBq/m(3). The average activity concentration of (210)Po during the route Gothenburg-Montevideo in 1988 was 63 and on the return Montevideo

  16. Compact perturbative expressions for neutrino oscillations in matter

    DOE PAGES

    Denton, Peter B.; Minakata, Hisakazu; Parke, Stephen J.

    2016-06-08

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

  17. Neutrinos from type II supernovae - The first 100 milliseconds

    NASA Technical Reports Server (NTRS)

    Myra, Eric S.; Burrows, Adam

    1990-01-01

    The collapse of a 1.17 solar mass iron core is numerically followed through infall to 100 ms past core bounce, and the emergent neutrino spectra during each phase are highlighted. It is found that, even with fairly optimistic conditions for producing a strong, sustained core-bounce shock wave, the prompt shock stalls within 9 ms of core bounce at a radius of less than 250 km. It appears that a radical change in the character of the progenitor core or in our understanding of the relevant physics of stellar collapse is needed before the direct mechanism for type II supernovae can become viable. Expanding the number of neutrino types from one to six magnifies the debilitating effect of neutrino loss on shock propagation. At shock breakout, prompt bursts of all neutrino types are observed. The luminosities of the nonelectron types show a sudden turn-on in luminosity while that of the electron neutrinos steadily increases throughout infall as a result of accelerating electron capture.

  18. Compact perturbative expressions for neutrino oscillations in matter

    NASA Astrophysics Data System (ADS)

    Denton, Peter B.; Minakata, Hisakazu; Parke, Stephen J.

    2016-06-01

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

  19. PPPC 4 DMν: a Poor Particle Physicist Cookbook for Neutrinos from Dark Matter annihilations in the Sun

    SciTech Connect

    Baratella, Pietro; Cirelli, Marco; Hektor, Andi; Pata, Joosep; Piibeleht, Morten; Strumia, Alessandro

    2014-03-27

    We provide ingredients and recipes for computing neutrino signals of TeV-scale Dark Matter (DM) annihilations in the Sun. For each annihilation channel and DM mass we present the energy spectra of neutrinos at production, including: state-of-the-art energy losses of primary particles in solar matter, secondary neutrinos, electroweak radiation. We then present the spectra after propagation to the Earth, including (vacuum and matter) flavor oscillations and interactions in solar matter. We also provide a numerical computation of the capture rate of DM particles in the Sun. These results are available in numerical form http://www.marcocirelli.net/PPPC4DMID.html.

  20. Predictions for the Dirac CP violation phase in the neutrino mixing matrix

    NASA Astrophysics Data System (ADS)

    Petcov, S. T.; Girardi, I.; Titov, A. V.

    2015-05-01

    Using the fact that the neutrino mixing matrix U = UeUν , where Ue and Uν result from the diagonalization of the charged lepton and neutrino mass matrices, we analyze the predictions based on the sum rules which the Dirac phase δ present in U satisfies when Uν has a form dictated by, or associated with, discrete flavor symmetries and Ue has a "minimal" form (in terms of angles and phases it contains) that can provide the requisite corrections to Uν, so that the reactor, atmospheric and solar neutrino mixing angles θ13, θ23 and θ12 have values compatible with the current data.

  1. Predictions for the Dirac CP Violation Phase in the Neutrino Mixing Matrix

    NASA Astrophysics Data System (ADS)

    Petcov, S. T.; Girardi, I.; Titov, A. V.

    Using the fact that the neutrino mixing matrix U = U_{e}^{dagger} U_{ν}, where Ue and Uν result from the diagonalization of the charged lepton and neutrino mass matrices, we analyze the predictions based on the sum rules which the Dirac phase δ present in U satisfies when Uν has a form dictated by, or associated with, discrete favor symmetries and Ue has a "minimal" form (in terms of angles and phases it contains) that can provide the requisite corrections to Uν, so that the reactor, atmospheric and solar neutrino mixing angles θ13, θ23 and θ12 have values compatible with the current data.

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

    NASA Technical Reports Server (NTRS)

    Schramm, David N.

    1991-01-01

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

  3. 7Be, 210Pb and 137Cs concentrations in cloud water.

    PubMed

    Bourcier, L; Masson, O; Laj, P; Paulat, P; Pichon, J-M; Chausse, P; Gurriaran, R; Sellegri, K

    2014-02-01

    Cloud water was sampled during 8 months, in 2008 and 2009, at the puy de Dome high-altitude atmospheric research station (France). The concentrations of (7)Be and (210)Pb, both naturally occurring radionuclides, and (137)Cs of anthropogenic origin, were determined. Those values are useful for a better knowledge of the aftermath cloud deposition and more generally for wet deposition assessment of radionuclides. This is of primary interest in case of a nuclear accident, especially considering (137)Cs deposition, both for high-altitude locations that are regularly embedded by clouds and also for lowlands where fog can occur. The (7)Be and (210)Pb average activity concentrations in cloud water found were 1.9±0.11 mBq m(-3) air and 140±10 μBq m(-3) air, respectively. For (137)Cs, the average concentration was 0.14±0.02 μBq m(-3) air. This very low-level is representative of the long term post-accidental background level. Indeed, for the studied period, the last accidental (137)Cs release was that of Chernobyl accident, in April 1986. To our knowledge this is the first data about (137)Cs reference level determination in cloud water. The comparison between cloud water and rain water concentrations showed a ratio cloud/rain ranging between 3.4 and 8.1, in agreement with previous studies performed on inorganic compounds. Scavenging efficiencies of aerosols by cloud droplets were also calculated with the additional aerosol concentrations routinely measured at the station and were quite low (0.13-0.40) compared to what has previously been observed for inorganic soluble ions.

  4. Wear measurement of highly cross-linked UHMWPE using a 7Be tracer implantation technique.

    PubMed

    Wimmer, Markus A; Laurent, Michel P; Dwiwedi, Yasha; Gallardo, Luis A; Chipps, Kelly A; Blackmon, Jeffery C; Kozub, Raymond L; Bardayan, Daniel W; Gross, Carl J; Stracener, Daniel W; Smith, Michael S; Nesaraja, Caroline D; Erikson, Luke; Patel, Nidhi; Rehm, Karl E; Ahmad, Irshad; Greene, John P; Greife, Uwe

    2013-04-01

    The very low wear rates achieved with the current highly cross-linked ultrahigh molecular weight polyethylenes (UHMWPE) used in joint prostheses have proven to be difficult to measure accurately by gravimetry. Tracer methods are therefore being explored. The purpose of this study was to perform a proof-of-concept experiment on the use of the radioactive tracer beryllium-7 ((7)Be) for the determination of in vitro wear in a highly cross-linked orthopedic UHMWPE. Three cross-linked and four conventional UHMWPE pins made from compression-molded GUR 1050, were activated with 10(9) to 10(10) (7)Be nuclei using a new implantation setup that produced a homogenous distribution of implanted nuclei up to 8.5 μm below the surface. The pins were tested for wear in a six-station pin-on-flat apparatus for up to 7.1 million cycles (178 km). A Germanium gamma detector was employed to determine activity loss of the UHMWPE pins at preset intervals during the wear test. The wear of the cross-linked UHMWPE pins was readily detected and estimated to be 17 ± 3 μg per million cycles. The conventional-to-cross-linked ratio of the wear rates was 13.1 ± 0.8, in the expected range for these materials. Oxidative degradation damage from implantation was negligible; however, a weak dependence of wear on implantation dose was observed limiting the number of radioactive tracer atoms that can be introduced. Future applications of this tracer technology may include the analysis of location-specific wear, such as loss of material in the post or backside of a tibial insert.

  5. Neutrino oscillations with a proton driver upgrade and an off-axis detector: A Case study

    SciTech Connect

    Barenboim, Gabriela; De Gouvea, Andre; Szleper, Michal; Velasco, Mayda

    2002-04-01

    We study the physics capabilities of the NuMI beamline with an off-axis highly-segmented iron scintillator detector and with the inclusion of the currently under study proton driver upgrade. We focus on the prospects for the experimental determination of the remaining neutrino oscillation parameters, assuming different outcomes for experiments under way or in preparation. An optimization of the beam conditions and detector location for the detection of the nu_mu to nu_e transitions is discussed. Different physics scenarios were considered, depending on the actual solution of the solar neutrino puzzle. If KamLAND measures Delta m^2_solar, we find it possible to measure both |U_{e3}|^2 and the CP violating phase delta within a viable exposure time, assuming a realistic detector and a complete data analysis. Exposure to both neutrino and antineutrino beams is necessary. We can, in addition, shed light on Delta m^2_solar if its value is at the upper limit of KamLAND sensitivity (i.e. the precise value of Delta m^2_solar remains unknown even after KamLAND). If the solar neutrino solution is not in the LMA region, we can measure |U_{e3}|^2 and determine the neutrino mass hierarchy. The existence of the proton driver is vital for the feasibility of most of these measurements.

  6. From Superbeams to Neutrino Factories

    SciTech Connect

    Bross, Alan

    2010-03-30

    The Neutrino Factory, which produces an extremely intense source of flavor-tagged neutrinos from muon decays in a storage ring, arguably gives the best physics reach for CP violation, as well as virtually all parameters in the neutrino oscillation parameter space. I will briefly describe the physics capabilities of the baseline Neutrino Factory as compared to other possible future facilities (beta-beam and super-beam facilities), give an overview of the accelerator complex and describe in detail the current international R and D program.

  7. Magnus approximation in neutrino oscillations

    NASA Astrophysics Data System (ADS)

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

    2011-04-01

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

  8. MINOS atmospheric neutrino contained events

    SciTech Connect

    Habig, A.; /Minnesota U.

    2007-10-01

    The Main Injector Neutrino Oscillation Search (MINOS) experiment has continued to collect atmospheric neutrino events while doing a precision measurement of NuMI beam {nu}{sub {mu}} disappearance oscillations. The 5.4 kton iron calorimeter is magnetized to provide the unique capability of discriminating between {nu}{sub {mu}} and {bar {nu}}{sub {mu}} interactions on an event-by-event basis and has been collecting atmospheric neutrino data since July 2003. An analysis of the neutrino events with interaction vertices contained inside the detector will be presented.

  9. Probing neutrino nature at Borexino detector with chromium neutrino source

    NASA Astrophysics Data System (ADS)

    Sobków, W.; Błaut, A.

    2016-10-01

    In this paper, we indicate a possibility of utilizing the intense chromium source (˜ 370 PBq) in probing the neutrino nature in low energy neutrino experiments with the ultra-low threshold and background real-time Borexino detector located near the source (˜ 8 m). We analyse the elastic scattering of electron neutrinos (Dirac or Majorana, respectively) on the unpolarised electrons in the relativistic neutrino limit. We assume that the incoming neutrino beam is the superposition of left-right chiral states produced by the chromium source. Left chiral neutrinos may be detected by the standard V - A and non-standard scalar S_L, pseudoscalar P_L, tensor T_L interactions, while right chiral ones partake only in the exotic V + A and S_R, P_R, T_R interactions. Our model-independent study is carried out for the flavour (current) neutrino eigenstates. We compute the expected event number for the standard V-A interaction of the left chiral neutrinos using the current experimental values of standard couplings and in the case of left-right chiral superposition. We show that the significant decrement in the event number due to the interference terms between the standard and exotic interactions for the Majorana neutrinos may appear. We also demonstrate how the presence of the exotic couplings affects the energy spectrum of outgoing electrons, both for the Dirac and Majorana cases. The 90~% C.L. sensitivity contours in the planes of corresponding exotic couplings are found. The presence of interferences in the Majorana case gives the stronger constraints than for the Dirac neutrinos, even if the neutrino source is placed outside the detector.

  10. The Enigmatic Neutrino

    NASA Astrophysics Data System (ADS)

    Lincoln, Don; Miceli, Tia

    2015-09-01

    Through a century of work, physicists have refined a model to describe all fundamental particles, the forces they share, and their interactions on a microscopic scale. This masterpiece of science is called the Standard Model. While this theory is incredibly powerful, we know of at least one particle that exhibits behaviors that are outside of its scope and remain unexplained. These particles are called neutrinos and they are the enigmatic ghosts of the quantum world. Interacting only via the weak nuclear force, literally billions of them pass through you undetected every second. While we understand that particular spooky behavior, we do not understand in any fundamental way how it is that neutrinos can literally change their identity, much as if a house cat could turn into a lion and then a tiger before transitioning back into a house cat again.

  11. Gravity triggered neutrino condensates

    SciTech Connect

    Barenboim, Gabriela

    2010-11-01

    In this work we use the Schwinger-Dyson equations to study the possibility that an enhanced gravitational attraction triggers the formation of a right-handed neutrino condensate, inducing dynamical symmetry breaking and generating a Majorana mass for the right-handed neutrino at a scale appropriate for the seesaw mechanism. The composite field formed by the condensate phase could drive an early epoch of inflation. We find that to the lowest order, the theory does not allow dynamical symmetry breaking. Nevertheless, thanks to the large number of matter fields in the model, the suppression by additional powers in G of higher order terms can be compensated, boosting them up to their lowest order counterparts. This way chiral symmetry can be broken dynamically and the infrared mass generated turns out to be in the expected range for a successful seesaw scenario.

  12. Neutrino catalyzed diphoton excess

    NASA Astrophysics Data System (ADS)

    Chao, Wei

    2016-10-01

    In this paper we explain the 750 GeV diphoton resonance observed at the run-2 LHC as a scalar singlet S, that plays a key role in generating tiny but nonzero Majorana neutrino masses. The model contains four electroweak singlets: two leptoquarks, a singly charged scalar and a neutral scalar S. Majorana neutrino masses might be generated at the two-loop level as S gets nonzero vacuum expectation value. S can be produced at the LHC through the gluon fusion and decays into diphoton with charged scalars running in the loop. The model fits perfectly with a narrow width of the resonance. Constraints on the model are investigated, which shows a negligible mixing between the resonance and the standard model Higgs boson.

  13. Prospecting with neutrinos

    NASA Astrophysics Data System (ADS)

    Bell, Peter M.

    One of the latest attempts to explore the interface between physics and geophysics is the extravagant scheme of Alvaro De Rújula, Sheldon Glashow, Robert Wilson, and Georges Charpak, to be published in Physics Reports. In what these theoretical and experimental physicists described recently as “our mad project” (Physics Today, August 1983), a high-energy neutrino beam is to be used as a geophysical prospecting tool.The beam would be able to look for oil, natural gas, and high-atomic-number metal ores, and it would be able to profile the vertical density distribution of the earth. De Rújula et al. come to this project from the world of big physics machines, so it is natural to expect that the “Geotron,” the field instrument to supply and focus the neutrino beam, is to be big also.

  14. Enhanced sensitivity to dark matter self-annihilations in the Sun using neutrino spectral information

    NASA Astrophysics Data System (ADS)

    Rott, C.; Tanaka, T.; Itow, Y.

    2011-09-01

    Self-annihilating dark matter gravitationally captured by the Sun could yield observable neutrino signals at current and next generation neutrino detectors. By exploiting such signals, neutrino detectors can probe the spin-dependent scattering of weakly interacting massive particles (WIMPs) with nucleons in the Sun. We describe a method how to convert constraints on neutrino fluxes to a limit on the WIMP-nucleon scattering cross section. In this method all neutrino flavors can be treated in a very similar way. We study the sensitivity of neutrino telescopes for Solar WIMP signals using vertex contained events and find that this detection channel is of particular importance in the search for low mass WIMPs. We obtain highly competitive sensitivities with all neutrino flavor channels for a Megaton sized detector through the application of basic spectral selection criteria. Best results are obtained with the electron neutrino channel. We discuss associated uncertainties and provide a procedure how to treat them for analyses in a consistent way.

  15. Barr-Freire-Zee mechanism for the hydrogen-ionizing decaying neutrino dark matter

    NASA Astrophysics Data System (ADS)

    Tommasini, Daniele

    1992-12-01

    We consider the scenario of the hydrogen-ionizing decaying neutrino dark matter, advocated by Sciama to solve several ionization problems in astrophysics and cosmology. We show that dangerously large neutrino oscillations are expected in general in the particle physics models introduced to provide the required neutrino masses and dark matter decay lifetime. However, the implementation of a mechanism recently discovered by Barr, Freire and Zee, allows to realize this scenario free of large neutrino oscillations. Furthermore, in this case a mass scale for the light neutrinos, which can be naturally the MSW solar neutrino scale ~ 10-3 eV, is automatically associated to the value ~ 1023 s of the dark matter decay lifetime, needed to solve the ionization problems. A realization of the mechanism in the supersymmetric standard model with broken R-parity is then considered as an example. In that case, the heavy neutrino providing the dark matter is made up mainly by the standard muon neutrino νμ.

  16. Small neutrino masses from gravitational θ -term

    NASA Astrophysics Data System (ADS)

    Dvali, Gia; Funcke, Lena

    2016-06-01

    We present how a neutrino condensate and small neutrino masses emerge from a topological formulation of gravitational anomaly. We first recapitulate how a gravitational θ -term leads to the emergence of a new bound neutrino state analogous to the η' meson of QCD. Then we show the consequent formation of a neutrino vacuum condensate, which effectively generates small neutrino masses. Afterwards we outline numerous phenomenological consequences of our neutrino mass generation model. The cosmological neutrino mass bound vanishes since we predict the neutrinos to be massless until the phase transition in the late Universe, T ˜meV . Coherent radiation of new light particles in the neutrino sector can be detected in prospective precision experiments. Deviations from an equal flavor rate due to enhanced neutrino decays in extraterrestrial neutrino fluxes can be observed in future IceCube data. These neutrino decays may also necessitate modified analyses of the original neutrino spectra of the supernova SN 1987A. The current cosmological neutrino background only consists of the lightest neutrinos, which, due to enhanced neutrino-neutrino interactions, either bind up, form a superfluid, or completely annihilate into massless bosons. Strongly coupled relic neutrinos could provide a contribution to cold dark matter in the late Universe, together with the new proposed particles and topological defects, which may have formed during neutrino condensation. These enhanced interactions could also be a source of relic neutrino clustering in our Galaxy, which possibly makes the overdense cosmic neutrino background detectable in the KATRIN experiment. The neutrino condensate provides a mass for the hypothetical B -L gauge boson, leading to a gravity-competing force detectable in short-distance measurements. Prospective measurements of the polarization intensities of gravitational waves can falsify our neutrino mass generation model.

  17. Experimental Neutrino Physics

    ScienceCinema

    Walter, Chris [Duke University, Durham, North Carolina, United States

    2016-07-12

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

  18. Natural Neutrino Dark Energy

    SciTech Connect

    Gurwich, Ilya

    2010-06-23

    1 construct a general description for neutrino dark energy models, that do not require exotic particles or strange couplings. With the help of the above, this class of models is reduced to a single function with several constraints. It is shown that these models lead to some concrete predictions that can be verified (or disproved) within the next decade, using results from PLANK, EUCLID and JDEM.

  19. Birth of Neutrino Astrophysics

    ScienceCinema

    None

    2016-07-12

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

  20. Neutrinos and flavor symmetries

    SciTech Connect

    Tanimoto, Morimitsu

    2015-07-15

    We discuss the recent progress of flavor models with the non-Abelian discrete symmetry in the lepton sector focusing on the θ{sub 13} and CP violating phase. In both direct approach and indirect approach of the flavor symmetry, the non-vanishing θ{sub 13} is predictable. The flavor symmetry with the generalised CP symmetry can also predicts the CP violating phase. We show the phenomenological analyses of neutrino mixing for the typical flavor models.

  1. Birth of Neutrino Astrophysics

    SciTech Connect

    2010-05-07

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

  2. Neutrinos and flavor symmetries

    NASA Astrophysics Data System (ADS)

    Tanimoto, Morimitsu

    2015-07-01

    We discuss the recent progress of flavor models with the non-Abelian discrete symmetry in the lepton sector focusing on the θ13 and CP violating phase. In both direct approach and indirect approach of the flavor symmetry, the non-vanishing θ13 is predictable. The flavor symmetry with the generalised CP symmetry can also predicts the CP violating phase. We show the phenomenological analyses of neutrino mixing for the typical flavor models.

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

    NASA Astrophysics Data System (ADS)

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

    2016-06-01

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

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

    DOE PAGES

    Park, J.; Aliaga, L.; Altinok, O.; Bellantoni, L.; Bercellie, A.; Betancourt, M.; Bodek, A.; Bravar, A.; Budd, H.; Cai, T.; et al

    2016-06-10

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

  5. Temporal changes of 7Be, 137Cs and 210Pb activity concentrations in surface air at Monaco and their correlation with meteorological parameters.

    PubMed

    Pham, Mai K; Betti, Maria; Nies, Hartmut; Povinec, Pavel P

    2011-11-01

    Results of analysis of (7)Be, (137)Cs and (210)Pb on aerosol filters carried out from 1998 to 2010 in Monaco show that a weak correlation between activity concentrations of these radionuclides in the atmosphere and meteorological parameters has been found for (7)Be and temperature (r = 0.50), (210)Pb and temperature and humidity (r = 0.43 and 0.41, respectively), and (137)Cs and precipitation (r = 0.51). The minimum and maximum (7)Be activity concentrations were observed during 2000 and 2009, corresponding with the maximum and minimum solar activity, respectively. The maximum (137)Cs activity concentration found in May-June 1998 was due to the accident at Algeciras in Spain. The deposition velocities of (7)Be, (137)Cs and (210)Pb depended on the precipitation rate, and attained maximum values during dry seasons. The investigated radionuclides may be used as atmospheric tracers, especially in long-term periods.

  6. Probing Neutrino Properties with Long-Baseline Neutrino Beams

    SciTech Connect

    Marino, Alysia

    2015-06-29

    This is nal report on an Early Career Award grant began in April 15, 2010 and concluded on April 14, 2015. Alysia Marino's research is fo- cussed on making precise measurements of neutrino properties using in- tense accelerator-generated neutrino beams. As a part of this grant, she is collaborating on the Tokai-to-Kamioka (T2K) long-baseline neutrino exper- iment [6], currently taking data in Japan, and on the Deep Underground Neutrino Experiment (DUNE) design e ort for a future Long-Baseline Neu- trino Facility (LBNF) in the US.1 She is also a member of the NA61/SHINE particle production experiment at CERN, but as that e ort is supported by other funds, it will not be discussed further here. T2K was designed to search for the disappearance of muon neutrinos ( ) and the appearance of electron neutrinos ( e), using a beam of muon neu- trino beam that travels 295 km across Japan towards the Super-Kamiokande detector. In 2011 T2K rst reported indications of e appearance [2], a pre- viously unobserved mode of neutrino oscillations. In the past year, T2K has published a combined analysis of disappearance and e appearance [1], and began collecting taking data with a beam of anti-neutrinos, instead of neutrinos, to search for hints of violation of the CP symmetry of the uni- verse. The proposed DUNE experiment has similar physics goals to T2K, but will be much more sensitive due to its more massive detectors and new higher-intensity neutrino beam. This e ort will be very high-priority particle physics project in the US over the next decade.

  7. The Mystery of Neutrino Mixings

    NASA Astrophysics Data System (ADS)

    Altarelli, Guido

    2013-07-01

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

  8. Is There a Massive Neutrino?

    ERIC Educational Resources Information Center

    Selvin, Paul

    1991-01-01

    Discussed is the question of whether "heavy" neutrinos really do exist based on the evidence supplied by four research groups. The implications of its existence on the disciplines of particle physics, astrophsyics, and cosmology are discussed. Background information on the different types of neutrinos is provided. (KR)

  9. Neutrino Oscillations with Nil Mass

    NASA Astrophysics Data System (ADS)

    Floyd, Edward R.

    2016-09-01

    An alternative neutrino oscillation process is presented as a counterexample for which the neutrino may have nil mass consistent with the standard model. The process is developed in a quantum trajectories representation of quantum mechanics, which has a Hamilton-Jacobi foundation. This process has no need for mass differences between mass eigenstates. Flavor oscillations and ν ,bar{ν } oscillations are examined.

  10. Neutrino cross-sections: Experiments

    SciTech Connect

    Sánchez, F.

    2015-07-15

    Neutrino-nucleus cross-sections are as of today the main source of systematic errors for oscillation experiments together with neutrino flux uncertainties. Despite recent experimental and theoretical developments, future experiments require even higher precisions in their search of CP violation. We will review the experimental status and explore possible future developments required by next generation of experiments.

  11. Neutrinos Get Under Your Skin

    SciTech Connect

    Kayser, Boris

    2005-08-30

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

  12. Neutrino oscillation results from MINOS

    SciTech Connect

    Sousa, Alexandre; /Oxford U.

    2007-08-01

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

  13. Theory and phenomenology of supernova neutrinos

    SciTech Connect

    Lunardini, Cecilia

    2015-07-15

    The theory and phenomenology of supernova neutrinos is reviewed, with focus on the most recent advancements on the neutrino flux predicted by supernova numerical models, on neutrino oscillations inside the star and in the Earth, and on the physics of the diffuse supernova neutrino background. Future directions of research are briefly summarized.

  14. Thermodynamic Laws of Neutrino and Photon Emission.

    ERIC Educational Resources Information Center

    Walsh, P. J.; Gallo, C. F.

    1980-01-01

    Compares neutrino and photon emissions, develops the thermodynamic blackbody laws of neutrino emission analogous to laws governing photon emission, points out that combined radiation from a "true blackbody" consists of both photon and neutrino emissions of comparable magnitude, and speculates upon the existence of blackbody neutrino emitters in…

  15. Light sterile neutrinos: Status and perspectives

    NASA Astrophysics Data System (ADS)

    Giunti, Carlo

    2016-07-01

    The indications in favor of the existence of light sterile neutrinos at the eV scale found in short-baseline neutrino oscillation experiments is reviewed. The future perspectives of short-baseline neutrino oscillation experiments and the connections with β-decay measurements of the neutrino masses and with neutrinoless double-β decay experiments are discussed.

  16. What masses do the neutrinos have? Mixing

    SciTech Connect

    Efrosinin, V. P.

    2010-06-15

    Possible mechanisms for the production of low-mass neutrinos and sterile neutrinos are considered. The quark mixing angles are calculated under the assumption that the traces of left-right symmetry are stable with respect to the masses of constituent quarks. Order-of-magnitude estimates of the neutrino masses are obtained with the aid of experimental data on neutrino oscillations.

  17. Neutrino mass models and CP violation

    SciTech Connect

    Joshipura, Anjan S.

    2011-10-06

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

  18. SEARCH FOR GLOBAL f-MODES AND p-MODES IN THE {sup 8}B NEUTRINO FLUX

    SciTech Connect

    Lopes, Ilídio E-mail: ilopes@uevora.pt

    2013-11-01

    The impact of global acoustic modes on the {sup 8}B neutrino flux time series is computed for the first time. It is shown that the time fluctuations of the {sup 8}B neutrino flux depend on the amplitude of acoustic eigenfunctions in the region where the {sup 8}B neutrino flux is produced: modes with low n (or order) that have eigenfunctions with a relatively large amplitude in the Sun's core strongly affect the neutrino flux; conversely, modes with high n that have eigenfunctions with a minimal amplitude in the Sun's core have a very small impact on the neutrino flux. It was found that the global modes with a larger impact on the {sup 8}B neutrino flux have a frequency of oscillation in the interval 250 μHz to 500 μHz (or a period in the interval 30 minutes to 70 minutes), such as the f-modes (n = 0) for the low degrees, radial modes of order n ≤ 3, and the dipole mode of order n = 1. Their corresponding neutrino eigenfunctions are very sensitive to the solar inner core and are unaffected by the variability of the external layers of the solar surface. If time variability of neutrinos is observed for these modes, it will lead to new ways of improving the sound speed profile inversion in the central region of the Sun.

  19. Status of High-Energy Neutrino Astronomy

    NASA Astrophysics Data System (ADS)

    Kowalski, Marek

    2015-08-01

    With the recent discovery of high-energy neutrinos of extra-terrestrial origin by the IceCube neutrino observatory, neutrino-astronomy is entering a new era. This review will cover currently operating open water/ice neutrino telescopes, the latest evidence for a flux of extra-terrestrial neutrinos and current efforts in the search for steady and transient neutrino point sources. Generalised constraints on potential astrophysical sources are presented, allowing to focus the hunt for the sources of the observed high-energy neutrinos.

  20. Large transition magnetic moment of the neutrino from horizontal symmetry

    NASA Astrophysics Data System (ADS)

    Babu, K. S.; Mohapatra, Rabindra N.

    1990-12-01

    The apparent anticorrelation of the solar-neutrino signal with the 11-yr sunspot cycle observed by Davis can be understood if the electron neutrino has a large magnetic moment. We discuss extensions of the standard model, where the existence of a leptonic SU(2)H-horizontal symmetry between the electron and muon generations provides a way to understand such a large magnetic moment, while keeping the neutrino mass naturally small. A global le-lμ symmetry (li=ith lepton number) is maintained even after spontaneous gauge symmetry breaking, so that the neutrino is of Zeldovich-Konopinski-Mahmoud type with m2νe-m2νμ=0. This condition automatically guarantees that the neutrino spin precession in the magnetic field of the Sun is not suppressed. Of the two extensions of the standard model that we discuss, the first one is a local SU(2)H model with the horizontal symmetry broken completely at a TeV scale. We show how a global U(1)le-lμ can be maintained although le-lμ is a subgroup of the gauged SU(2)H. The second example is the minimal supersymmetric extension of the standard model with R-parity-violating [but (le-lμ)-conserving] interactions. An approximate SU(2)H symmetry between the e-μ families is imposed in order to suppress the neutrino mass, but not its magnetic moment. We provide a detailed theoretical and phenomenological investigation of these two models and discuss their tests at the colliders as well as in low-energy experiments. The models generally predict mνe~=1-10 eV and the existence of charged scalar particles in the mass range of 100 GeV.

  1. Sterile Neutrinos in Cold Climates

    SciTech Connect

    Jones, Benjamin J.P.

    2015-09-01

    Measurements of neutrino oscillations at short baselines contain an intriguing set of experimental anomalies that may be suggestive of new physics such as the existence of sterile neutrinos. This three-part thesis presents research directed towards understanding these anomalies and searching for sterile neutrino oscillations. Part I contains a theoretical discussion of neutrino coherence properties. The open-quantum-system picture of neutrino beams, which allows a rigorous prediction of coherence distances for accelerator neutrinos, is presented. Validity of the standard treatment of active and sterile neutrino oscillations at short baselines is verified, and non-standard coherence loss effects at longer baselines are predicted. Part II concerns liquid argon detector development for the MicroBooNE experiment, which will search for short-baseline oscillations in the Booster Neutrino Beam at Fermilab. Topics include characterization and installation of the MicroBooNE optical system; test-stand measurements of liquid argon optical properties with dissolved impurities; optimization of wavelength-shifting coatings for liquid argon scintillation light detection; testing and deployment of high-voltage surge arrestors to protect TPC field cages; and software development for optical and TPC simulation and reconstruction. Part III presents a search for sterile neutrinos using the IceCube neutrino telescope, which has collected a large sample of atmospheric-neutrino-induced events in the 1-10 TeV energy range. Sterile neutrinos would modify the detected neutrino flux shape via MSW-resonant oscillations. Following a careful treatment of systematic uncertainties in the sample, no evidence for MSW-resonant oscillations is observed, and exclusion limits on 3+1 model parameter space are derived. Under the mixing assumptions made, the 90% confidence level exclusion limit extends to sin224 ≤ 0.02 at m2 ~ 0.3 eV2, and the LSND and Mini

  2. Integrated Nucleosynthesis in Neutrino Driven Winds

    SciTech Connect

    Roberts, L F; Woosley, S E; Hoffman, R D

    2010-03-26

    Although they are but a small fraction of the mass ejected in core-collapse supernovae, neutrino-driven winds (NDWs) from nascent proto-neutron stars (PNSs) have the potential to contribute significantly to supernova nucleosynthesis. In previous works, the NDW has been implicated as a possible source of r-process and light p-process isotopes. In this paper we present time-dependent hydrodynamic calculations of nucleosynthesis in the NDW which include accurate weak interaction physics coupled to a full nuclear reaction network. Using two published models of PNS neutrino luminosities, we predict the contribution of the NDW to the integrated nucleosynthetic yield of the entire supernova. For the neutrino luminosity histories considered, no true r-process occurs in the most basic scenario. The wind driven from an older 1.4M{sub {circle_dot}} model for a PNS is moderately neutron-rich at late times however, and produces {sup 87}Rb, {sup 88}Sr, {sup 89}Y, and {sup 90}Zr in near solar proportions relative to oxygen. The wind from a more recently studied 1.27M{sub {circle_dot}} PNS is proton-rich throughout its entire evolution and does not contribute significantly to the abundance of any element. It thus seems very unlikely that the simplest model of the NDW can produce the r-process. At most, it contributes to the production of the N = 50 closed shell elements and some light p-nuclei. In doing so, it may have left a distinctive signature on the abundances in metal poor stars, but the results are sensitive to both uncertain models for the explosion and the masses of the neutron stars involved.

  3. Determination of the residence time of suspended particles in the turbidity maximum of the Loire estuary by 7Be analysis

    NASA Astrophysics Data System (ADS)

    Ciffroy, Philippe; Reyss, Jean-Louis; Siclet, Françoise

    2003-07-01

    The aim of the present work was to evaluate the half life of suspended particles in the Loire estuarine turbidity maximum by analysis of 7Be budgets. The methodology was based on in situ sampling and further measurements aiming at quantifying 7Be sources (atmospheric deposition and river inputs) and 7Be stock in the water column of the turbidity maximum. 7Be river inputs were determined by monthly 7Be measurements performed upstream of the estuary. 7Be atmospheric deposition was estimated by using an empirical relation between 7Be deposition and rainfall. 7Be in particles of the estuarine turbidity maximum was measured at eight different dates corresponding to different tidal and hydrological conditions. 7Be sources and stocks thus determined have been compared to a mathematical model. Results allow to quantify the 'standard half life' of suspended particles in the Loire estuarine turbidity maximum and show that it depends on the season (6-10 months in summer and about 0.7 month during flood periods). Furthermore, a rather good linear correlation was observed between the standard half life of particles and the sum of flow rates in the Loire river during 60 days before each sampling date. The kinetic evolution of the mass of particles within the turbidity maximum could be estimated by this method and appeared to be consistent with previous studies. Moreover, the method proposed in this study could presumably be used for estimating 60Co concentrations in the estuarine turbidity maximum.

  4. Short-term seasonal variability in 7Be wet deposition in a semiarid ecosystem of central Argentina.

    PubMed

    Juri Ayub, J; Di Gregorio, D E; Velasco, H; Huck, H; Rizzotto, M; Lohaiza, F

    2009-11-01

    The (7)Be wet deposition has been intensively investigated in a semiarid region at San Luis Province, Argentina. From November 2006 to May 2008, the (7)Be content in rainwater was determined in 58 individual rain events, randomly comprising more than 50% of all individual precipitations at the sampling period. (7)Be activity concentration in rainwater ranged from 0.7+/-0.3 Bq l(-1) to 3.2+/-0.7 Bq l(-1), with a mean value of 1.7 Bq l(-1) (sd=0.53 Bq l(-1)). No relationship was found between (7)Be content in rainwater and (a) rainfall amount, (b) precipitation intensity and (c) elapsed time between events. (7)Be ground deposition was found to be well correlated with rainfall amount (R=0.92). For the precipitation events considered, the (7)Be depositional fluxes ranged from 1.1 to 120 Bq m(-2), with a mean value of 32.7 Bq m(-2) (sd=29.9 Bq m(-2)). The annual depositional flux was estimated at 1140+/-120 Bq m(-2)y(-1). Assuming the same monthly deposition pattern and that the (7)Be content in soil decreases only through radioactive decay, the seasonal variation of (7)Be areal activity density in soil was estimated. Results of this investigation may contribute to a valuable characterization of (7)Be input in the explored semiarid ecosystem and its potential use as tracer of environmental processes.

  5. Neutrino and Anti-neutrino Cross Sections at MiniBooNE

    SciTech Connect

    Dharmapalan, Ranjan

    2011-10-06

    The MiniBooNE experiment has reported a number of high statistics neutrino and anti-neutrino cross sections -among which are the charged current quasi-elastic (CCQE) and neutral current elastic (NCE) neutrino scattering on mineral oil (CH{sub 2}). Recently a study of the neutrino contamination of the anti-neutrino beam has concluded and the analysis of the anti-neutrino CCQE and NCE scattering is ongoing.

  6. Neutrino mass without cosmic variance

    NASA Astrophysics Data System (ADS)

    LoVerde, Marilena

    2016-05-01

    Measuring the absolute scale of the neutrino masses is one of the most exciting opportunities available with near-term cosmological data sets. Two quantities that are sensitive to neutrino mass, scale-dependent halo bias b (k ) and the linear growth parameter f (k ) inferred from redshift-space distortions, can be measured without cosmic variance. Unlike the amplitude of the matter power spectrum, which always has a finite error, the error on b (k ) and f (k ) continues to decrease as the number density of tracers increases. This paper presents forecasts for statistics of galaxy and lensing fields that are sensitive to neutrino mass via b (k ) and f (k ). The constraints on neutrino mass from the auto- and cross-power spectra of spectroscopic and photometric galaxy samples are weakened by scale-dependent bias unless a very high density of tracers is available. In the high-density limit, using multiple tracers allows cosmic variance to be beaten, and the forecasted errors on neutrino mass shrink dramatically. In practice, beating the cosmic-variance errors on neutrino mass with b (k ) will be a challenge, but this signal is nevertheless a new probe of neutrino effects on structure formation that is interesting in its own right.

  7. Analyzing Atmospheric Neutrino Oscillations

    SciTech Connect

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

    2007-10-26

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

  8. MUON STORAGE RINGS - NEUTRINO FACTORIES

    SciTech Connect

    PARSA,Z.

    2000-05-30

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

  9. Neutrino oscillations in low density medium.

    PubMed

    Ioannisian, A N; Smirnov, A Y

    2004-12-10

    We have solved the evolution equation for neutrinos in a low density medium, Vsolar and supernova neutrinos in matter of the Earth, substantially simplifying numerical calculations. Using these formulas we study sensitivity of the oscillations to structures of the density profile situated at different distances d from a detector. For the mass-to-flavor transitions, e.g., nu(2)-->nu(e), we have found the attenuation effect: a decrease of the sensitivity to remote structures, d>l(nu)E/DeltaE, where l(nu) is the oscillation length and DeltaE/E is the energy resolution of a detector.

  10. Supernova neutrino nucleosynthesis of light elements with neutrino oscillations.

    PubMed

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

    2006-03-10

    Light element synthesis in supernovae through neutrino-nucleus interactions, i.e., the v process, is affected by neutrino oscillations in the supernova environment. There is a resonance of 13-mixing in the O/C layer, which increases the rates of charged-current -process reactions in the outer He-rich layer. The yields of 7Li and 11B increase by about a factor of 1.9 and 1.3, respectively, for a normal mass hierarchy and an adiabatic 13-mixing resonance, compared to those without neutrino oscillations. In the case of an inverted mass hierarchy and a nonadiabatic 13-mixing resonance, the increase in the 7Li and 11B yields is much smaller. Observations of the 7Li/11B ratio in stars showing signs of supernova enrichment could thus provide a unique test of neutrino oscillations and constrain their parameters and the mass hierarchy.

  11. Neutrino-induced Reactions and Neutrino Scattering with Nuclear Targets

    NASA Astrophysics Data System (ADS)

    Cheoun, Myung-Ki; Ha, Eunja; Yang, Ghil-Seok; Kim, Kyungsik; Kajino, T.

    2016-02-01

    We reviewed present status regarding experimental data and theoretical approaches for neutrino-induced reactions and neutrino scattering. With a short introduction of relevant data, our recent calculations by distorted-wave Born approximation for quasielastic region are presented for MiniBooNE data. For much higher energy neutrino data, such as NOMAD data, elementary process approach was shown to be useful instead of using complicated nuclear models. But, in the low energy region, detailed nuclear structure model, such as QRPA and shell model, turn out to be inescapable to explain the reaction data. Finally, we discussed that one step-process in the reaction is comparable to the two-step process, which has been usually used in the neutrino-nucleosynthesis.

  12. A dedicated torsion balance to detect neutrinos by coherent scattering on high Debye temperature monocrystals

    NASA Astrophysics Data System (ADS)

    Cruceru, I.; Nicolescu, G.; Duliu, O. G.

    2008-11-01

    Coherent scattering of neutrinos on high Debye temperature monocrystals represent an alternative to detect solar as well as other high flux neutrino sources such as nuclear reactors or nuclear tests. Therefore, the possibility of detecting neutrinos by using sapphire monocrystals is presented and analyzed. Preliminary evaluations showed that 1 MeV neutrinos with a fluency density of 1012 cm-1 s-1 could interact with a 100 g sapphire monocrystal with a force of about 10-6 dyne, value measurable with a high sensitivity torsion balance. For this reason a torsion balance provided with 1 m length molybdenum or tungsten wire and an optical autocollimator able to measure small rotation angles of about 0.1 seconds of arc was designed, constructed and now is under preliminary tests. Both theoretical and practical implications of such kind of detector are presented and discussed.

  13. Anatomy of a cosmic-ray neutrino source and the Cygnus X-3 system

    NASA Technical Reports Server (NTRS)

    Stecker, F. W.; Harding, A. K.; Barnard, J. J.

    1985-01-01

    The effects of an intense beam of ultra-high energy cosmic rays from a compact object in the Cygnus X-3 binary system hitting the companion star, and of the subsequent production of secondary neutrinos, are examined. A maximum allowable beam luminosity of about 10 to the 42nd erg/s is found for a system containing a 1-10 solar mass main sequence target star. The proton beam must heat a relatively small area of the target star to satisfy observational constraints on the resulting stellar wind. With such a model, the neutrino to gamma-ray flux ratio of about 1000 can result from a combination of gamma-ray absorption and a large neutrino to gamma-ray duty cycle ratio. It is found that the high density of the atmosphere resulting from compression by the beam leads to pion cascading and a neutrino spectrum peaking at 1-10 GeV energies.

  14. Muon Neutrino to Electron Neutrino Oscillation in NOnuA

    NASA Astrophysics Data System (ADS)

    Sachdev, Kanika

    NOvA is a long-baseline neutrino oscillation experiment optimized for electron neutrino (nue) appearance in the NuMI beam, a muon neutrino (numu) source at Fermilab. It consists of two functionally identical, nearly fully-active liquid-scintillator tracking calorimeters. The near detector (ND) at Fermilab is used to study the neutrino beam spectrum and composition before oscillation, and measure background rate to the nu e appearance search. The far detector, 810 km away in Northern Minnesota, observes the oscillated beam and is used to extract oscillation parameters from the data. NOnuA's long baseline, combined with the ability of the NuMI beam to operate in the anti-neutrino mode, makes NOnuA sensitive to the last unmeasured parameters in neutrino oscillations- mass hierarchy, CP violation and the octant of mixing angle theta23. This thesis presents the search for nue appearance in the first data collected by the NOnuA detectors from October 2013 till May 2015. Studies of the NuMI neutrino data collected in the NOnuA near detector are also presented, which show large discrepancies between the ND simulation and data. Muon-removed electron (MRE) events, constructed by replacing the muon in numu charged current interactions by a simulated electron, are used to correct the far detector nue appearance prediction for these discrepancies. In the analysis of the first data, a total of 6 nue candidate events are observed in the far detector on a background of 1, a 3.46 sigma excess, which is interpreted as strong evidence for nue appearance. The results are consistent with our expectation, based on constraints from other neutrino oscillation experiments. The result presented here differs from the officially published nu e appearance result from the NOnuA experiment where the systematic error is assumed to cover the MRE correction.

  15. Models of neutrino mass, mixing and CP violation

    NASA Astrophysics Data System (ADS)

    King, Stephen F.

    2015-12-01

    In this topical review we argue that neutrino mass and mixing data motivates extending the Standard Model (SM) to include a non-Abelian discrete flavour symmetry in order to accurately predict the large leptonic mixing angles and {C}{P} violation. We begin with an overview of the SM puzzles, followed by a description of some classic lepton mixing patterns. Lepton mixing may be regarded as a deviation from tri-bimaximal mixing, with charged lepton corrections leading to solar mixing sum rules, or tri-maximal lepton mixing leading to atmospheric mixing rules. We survey neutrino mass models, using a roadmap based on the open questions in neutrino physics. We then focus on the seesaw mechanism with right-handed neutrinos, where sequential dominance (SD) can account for large lepton mixing angles and {C}{P} violation, with precise predictions emerging from constrained SD (CSD). We define the flavour problem and discuss progress towards a theory of favour using GUTs and discrete family symmetry. We classify models as direct, semidirect or indirect, according to the relation between the Klein symmetry of the mass matrices and the discrete family symmetry, in all cases focussing on spontaneous {C}{P} violation. Finally we give two examples of realistic and highly predictive indirect models with CSD, namely an A to Z of flavour with Pati-Salam and a fairly complete A 4 × SU(5) SUSY GUT of flavour, where both models have interesting implications for leptogenesis.

  16. Neutrino-nucleus reactions based on recent structure studies

    SciTech Connect

    Suzuki, Toshio

    2015-05-15

    Neutrino-nucleus reactions are studied with the use of new shell model Hamiltonians, which have proper tensor components in the interactions and prove to be successful in the description of Gamow-Teller (GT) strengths in nuclei. The new Hamiltonians are applied to obtain new neutrino-nucleus reaction cross sections in {sup 12}C, {sup 13}C, {sup 56}Fe and {sup 56}Ni induced by solar and supernova neutrinos. The element synthesis by neutrino processes in supernova explosions is discussed with the new cross sections. The enhancement of the production yields of {sup 7}Li, {sup 11}B and {sup 55}Mn is obtained while fragmented GT strength in {sup 56}Ni with two-peak structure is found to result in smaller e-capture rates at stellar environments. The monopole-based universal interaction with tensor force of π+ρ meson exchanges is used to evaluate GT strength in {sup 40}Ar and ν-induced reactions on {sup 40}Ar. It is found to reproduce well the experimental GT strength in {sup 40}Ar.

  17. Aspects of neutrino oscillation in alternative gravity theories

    SciTech Connect

    Chakraborty, Sumanta

    2015-10-01

    Neutrino spin and flavour oscillation in curved spacetime have been studied for the most general static spherically symmetric configuration. Having exploited the spherical symmetry we have confined ourselves to the equatorial plane in order to determine the spin and flavour oscillation frequency in this general set-up. Using the symmetry properties we have derived spin oscillation frequency for neutrino moving along a geodesic or in a circular orbit. Starting from the expression of neutrino spin oscillation frequency we have shown that even in this general context, in high energy limit the spin oscillation frequency for neutrino moving along circular orbit vanishes. We have verified previous results along this line by transforming to Schwarzschild coordinates under appropriate limit. This finally lends itself to the probability of neutrino helicity flip which turns out to be non-zero. While for neutrino flavour oscillation we have derived general results for oscillation phase, which subsequently have been applied to three different gravity theories. One, of them appears as low-energy approximation to string theory, where we have an additional field, namely, dilaton field coupled to Maxwell field tensor. This yields a realization of Reissner-Nordström solution in string theory at low-energy. Next one corresponds to generalization of Schwarzschild solution by introduction of quadratic curvature terms of all possible form to the Einstein-Hilbert action. Finally, we have also discussed regular black hole solutions. In all these cases the flavour oscillation probabilities can be determined for solar neutrinos and thus can be used to put bounds on the parameters of these gravity theories. While for spin oscillation probability, we have considered two cases, Gauss-Bonnet term added to the Einstein-Hilbert action and the f(R) gravity theory. In both these cases we could impose bounds on the parameters which are consistent with previous considerations. In a nutshell, in

  18. Simulation of the spherically symmetric stellar core collapse, bounce, and postbounce evolution of a star of 13 solar masses with boltzmann neutrino transport, and its implications for the supernova mechanism.

    PubMed

    Mezzacappa, A; Liebendörfer, M; Messer, O E; Hix, W R; Thielemann, F K; Bruenn, S W

    2001-03-01

    With exact three-flavor Boltzmann neutrino transport, we simulate the stellar core collapse, bounce, and postbounce evolution of a 13M star in spherical symmetry, the Newtonian limit, without invoking convection. In the absence of convection, prior spherically symmetric models, which implemented approximations to Boltzmann transport, failed to produce explosions. We consider exact transport to determine if these failures were due to the transport approximations made and to answer remaining fundamental questions in supernova theory. The model presented here is the first in a sequence of models beginning with different progenitors. In this model, a supernova explosion is not obtained.

  19. Research in Neutrino Physics

    SciTech Connect

    Busenitz, Jerome

    2014-09-30

    Research in Neutrino Physics We describe here the recent activities of our two groups over the first year of this award (effectively November 2010 through January 2012) and our proposed activities and associated budgets for the coming grant year. Both of our groups are collaborating on the Double Chooz reactor neutrino experiment and are playing major roles in calibration and analysis. A major milestone was reached recently: the collaboration obtained the first result on the search for 13 based on 100 days of data from the far detector. Our data indicates that 13 is not zero; specifically the best fit of the neutrino oscillation hypothesis to our data gives sin2 (2 13) = 0.086 ± 0.041 (stat) ± 0.030 (syst) The null oscillation hypothesis is excluded at the 94.6% C.L. This result1 has been submitted to Physical Review Letters. As we continue to take data with the far detector in the coming year, in parallel with completing the construction of the near lab and installing the near detector, we expect the precision of our measurement to improve as we gather significantly more statistics, gain better control of backgrounds through use of partial power data and improved event selection, and better understand the detector energy scale and detection efficiency from calibration data. With both detectors taking data starting in the second half of 2013, we expect to further drive down the uncertainty on our measurement of sin2 (2 13) to less than 0.02. Stancu’s group is also collaborating on the MiniBooNE experiment. Data taking is scheduled to continue through April, by which time 1.18 × 1021 POT is projected. The UA group is playing a leading role in the measurement of antineutrino cross sections, which should be the subject of a publication later this year as well as of Ranjan Dharmapalan’s Ph.D. thesis, which he is expected to defend by the end of this year. It is time to begin working on projects which will eventually succeed Double Chooz and MiniBooNE as the main

  20. Low level counting from meteorites to neutrinos

    SciTech Connect

    Heusser, Gerd

    2005-09-08

    The development in low level counting at Heidelberg with NaI(Tl) crystals, proportional counters and Germanium detectors is reviewed throughout the course of almost 40 years of experience. Research subjects changed from cosmogenic radionuclides in meteorites to solar neutrinos and double beta decay. Driven by screening measurements for these rare event experiments, the sensitivity in single gamma counting has gained almost 3 orders of magnitude. With Ge spectrometry the {mu}Bq/kg range is now accessible. It is discussed how further improvements can be realized. There is potential to reach a sensitivity at the level of 10 to 100 nBq/kg for cryogenic liquid type Gespectroscopy, a technique which the next generation 76Ge double beta decay experiment GERDA is based on.