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Sample records for beta decay branch

  1. Measurement of the branching ratio for beta-delayed alpha decay of 16N

    CERN Document Server

    Refsgaard, J; Dijck, E A; Fynbo, H O U; Lund, M V; Portela, M N; Raabe, R; Randisi, G; Renzi, F; Sambi, S; Sytema, A; Willmann, L; Wilschut, H W

    2015-01-01

    While the 12C(a,g)16O reaction plays a central role in nuclear astrophysics, the cross section at energies relevant to hydrostatic helium burning is too small to be directly measured in the laboratory. The beta-delayed alpha spectrum of 16N can be used to constrain the extrapolation of the E1 component of the S-factor; however, with this approach the resulting S-factor becomes strongly correlated with the assumed beta-alpha branching ratio. We have remeasured the beta-alpha branching ratio by implanting 16N ions in a segmented Si detector and counting the number of beta-alpha decays relative to the number of implantations. Our result, 1.49(5)e-5, represents a 25% increase compared to the accepted value and implies an increase of 14% in the extrapolated S-factor.

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

    CERN Document Server

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

    2012-01-01

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

  3. First direct observation of bound-state beta-decay: Measurements of branching and lifetime of 207Tl81+ fragments

    International Nuclear Information System (INIS)

    The first experimental observation of bound-state beta-decay showed, that due solely to the electron stripping, a stable nuclide, e.g. 163Dy, became unstable. Also a drastic modification of the half-life of bare 187Re, from 4.12(2) x 1010 years down to 32.9(20) years, could be observed. It was mainly due to the possibility for the mother nuclide to decay into a previously inaccessible nuclear level of the daughter nuclide. It was proposed to study a nuclide where this decay mode was competing with continuum-state beta-decay, in order to measure their respective branchings. The ratio βb/βc could also be evaluated for the first time. 207Tl was chosen due to its high atomic number, and Q-value of about 1.4 MeV, small enough to enhance the βb probability and large enough to allow the use of time-resolved Schottky Mass Spectrometry (SMS) to study the evolution of mother and bound-state beta-decay daughter ions. The decay properties of the ground state and isomeric state of 207Tl81+ have been investigated at the GSI accelerator facility in two separate experiments. For the first time β-decay where the electron could go either to a bound state (atomic orbitals) and lead to 207Pb81+ as a daughter nuclide, or to a continuum state and lead to 207Pb82+, has been observed. The respective branchings of these two processes could be measured as well. The deduced total nuclear half-life of 255(17) s for 207Tl81+, was slightly modified with respect to the half-life of the neutral atom of 286(2) s. It was nevertheless in very good agreement with calculations based on the assumption that the beta-decay was following an allowed type of transition. The branching βb/βc=0.192(20), was also in very good agreement with the same calculations. The application of stochastic precooling allowed to observe in addition the 1348 keV short-lived isomeric state of 207Tl. The half-life of this isomeric state was measured as 1.47(32) s, which shows a small deviation compared to the half-life for

  4. In-trap decay spectroscopy for {beta}{beta} decays

    Energy Technology Data Exchange (ETDEWEB)

    Brunner, Thomas

    2011-01-18

    The presented work describes the implementation of a new technique to measure electron-capture (EC) branching ratios (BRs) of intermediate nuclei in {beta}{beta} decays. This technique has been developed at TRIUMF in Vancouver, Canada. It facilitates one of TRIUMF's Ion Traps for Atomic and Nuclear science (TITAN), the Electron Beam Ion Trap (EBIT) that is used as a spectroscopy Penning trap. Radioactive ions, produced at the radioactive isotope facility ISAC, are injected and stored in the spectroscopy Penning trap while their decays are observed. A key feature of this technique is the use of a strong magnetic field, required for trapping. It radially confines electrons from {beta} decays along the trap axis while X-rays, following an EC, are emitted isotropically. This provides spatial separation of X-ray and {beta} detection with almost no {beta}-induced background at the X-ray detector, allowing weak EC branches to be measured. Furthermore, the combination of several traps allows one to isobarically clean the sample prior to the in-trap decay spectroscopy measurement. This technique has been developed to measure ECBRs of transition nuclei in {beta}{beta} decays. Detailed knowledge of these electron capture branches is crucial for a better understanding of the underlying nuclear physics in {beta}{beta} decays. These branches are typically of the order of 10{sup -5} and therefore difficult to measure. Conventional measurements suffer from isobaric contamination and a dominating {beta} background at theX-ray detector. Additionally, X-rays are attenuated by the material where the radioactive sample is implanted. To overcome these limitations, the technique of in-trap decay spectroscopy has been developed. In this work, the EBIT was connected to the TITAN beam line and has been commissioned. Using the developed beam diagnostics, ions were injected into the Penning trap and systematic studies on injection and storage optimization were performed. Furthermore, Ge

  5. Double beta decay experiments

    OpenAIRE

    Barabash, A. S.

    2011-01-01

    The present status of double beta decay experiments is reviewed. The results of the most sensitive experiments are discussed. Proposals for future double beta decay experiments with a sensitivity to the $$ at the level of (0.01--0.1) eV are considered.

  6. Calculation of Beta Decay Half-Lives and Delayed Neutron Branching Ratio of Fission Fragments with Skyrme-QRPA

    Directory of Open Access Journals (Sweden)

    Minato Futoshi

    2016-01-01

    Full Text Available Nuclear β-decay and delayed neutron (DN emission is important for the r-process nucleosynthesis after the freeze-out, and stable and safe operation of nuclear reactors. Even though radioactive beam facilities have enabled us to measure β-decay and branching ratio of neutron-rich nuclei apart from the stability line in the nuclear chart, there are still a lot of nuclei which one cannot investigate experimentally. In particular, information on DN is rather scarce than that of T1/2. To predict T1/2 and the branching ratios of DN for next JENDL decay data, we have developed a method which comprises the quasiparticle-random-phase-approximation (QRPA and the Hauser-Feshbach statistical model (HFSM. In this work, we calculate fission fragments with T1/2 ≤ 50 sec. We obtain the rms deviation from experimental half-life of 3:71. Although the result is still worse than GT2 which has been adopted in JENDL decay data, DN spectra are newly calculated. We also discuss further subjects to be done in future for improving the present approach and making next generation of JENDL decay data.

  7. Calculation of Beta Decay Half-Lives and Delayed Neutron Branching Ratio of Fission Fragments with Skyrme-QRPA

    Science.gov (United States)

    Minato, Futoshi

    2016-06-01

    Nuclear β-decay and delayed neutron (DN) emission is important for the r-process nucleosynthesis after the freeze-out, and stable and safe operation of nuclear reactors. Even though radioactive beam facilities have enabled us to measure β-decay and branching ratio of neutron-rich nuclei apart from the stability line in the nuclear chart, there are still a lot of nuclei which one cannot investigate experimentally. In particular, information on DN is rather scarce than that of T1/2. To predict T1/2 and the branching ratios of DN for next JENDL decay data, we have developed a method which comprises the quasiparticle-random-phase-approximation (QRPA) and the Hauser-Feshbach statistical model (HFSM). In this work, we calculate fission fragments with T1/2 ≤ 50 sec. We obtain the rms deviation from experimental half-life of 3:71. Although the result is still worse than GT2 which has been adopted in JENDL decay data, DN spectra are newly calculated. We also discuss further subjects to be done in future for improving the present approach and making next generation of JENDL decay data.

  8. First direct observation of bound-state beta-decay. Measurements of branching and lifetime of {sup 207}Tl{sup 81+} fragments

    Energy Technology Data Exchange (ETDEWEB)

    Boutin, D.

    2005-08-01

    The first experimental observation of bound-state beta-decay showed, that due solely to the electron stripping, a stable nuclide, e.g. {sup 163}Dy, became unstable. Also a drastic modification of the half-life of bare {sup 187}Re, from 4.12(2) x 10{sup 10} years down to 32.9(20) years, could be observed. It was mainly due to the possibility for the mother nuclide to decay into a previously inaccessible nuclear level of the daughter nuclide. It was proposed to study a nuclide where this decay mode was competing with continuum-state beta-decay, in order to measure their respective branchings. The ratio {beta}{sub b}/{beta}{sub c} could also be evaluated for the first time. {sup 207}Tl was chosen due to its high atomic number, and Q-value of about 1.4 MeV, small enough to enhance the {beta}{sub b} probability and large enough to allow the use of time-resolved Schottky Mass Spectrometry (SMS) to study the evolution of mother and bound-state beta-decay daughter ions. The decay properties of the ground state and isomeric state of {sup 207}Tl{sup 81+} have been investigated at the GSI accelerator facility in two separate experiments. For the first time {beta}-decay where the electron could go either to a bound state (atomic orbitals) and lead to {sup 207}Pb{sup 81+} as a daughter nuclide, or to a continuum state and lead to {sup 207}Pb{sup 82+}, has been observed. The respective branchings of these two processes could be measured as well. The deduced total nuclear half-life of 255(17) s for {sup 207}Tl{sup 81+}, was slightly modified with respect to the half-life of the neutral atom of 286(2) s. It was nevertheless in very good agreement with calculations based on the assumption that the beta-decay was following an allowed type of transition. The branching {beta}{sub b}/{beta}{sub c}=0.192(20), was also in very good agreement with the same calculations. The application of stochastic precooling allowed to observe in addition the 1348 keV short-lived isomeric state of {sup

  9. Neutrinoless double beta decay

    International Nuclear Information System (INIS)

    The physics potential of neutrinoless double beta decay is discussed. Furthermore, experimental considerations as well as the current status of experiments are presented. Finally, an outlook towards the future, work on nuclear matrix elements and alternative processes is given. (author)

  10. Neutrinoless double beta decay

    Indian Academy of Sciences (India)

    Kai Zuber

    2012-10-01

    The physics potential of neutrinoless double beta decay is discussed. Furthermore, experimental considerations as well as the current status of experiments are presented. Finally, an outlook towards the future, work on nuclear matrix elements and alternative processes is given.

  11. Precision measurement of the half-life and branching ratio of the T=1/2 mirror $\\beta$-decay of $^{37}$K

    CERN Multimedia

    We propose to study the T=1/2 mirror $\\beta$-decay of $^{37}$K. Nuclear mirror $\\beta$-decay is a competitive means to test the electroweak model by means of the high-precision measurement of V$_{ud}$ element of the CKM quark mixing matrix. One key ingredient to obtain V$_{ud}$ is the force of the transition, Ft, which has to be determined with a relative precision below 10$^{−3}$. This quantity is related to the half-life T$_{1/2}$ of the decaying nucleus, the branching ratio BR for this decay and the mass difference between the mother and daughter nucleus (Q value). Another important feature is the mixing ratio $\\rho$ between the Fermi and the Gamow-Teller character of the transition. In most cases, $\\rho$ is the major contributor to the uncertainty on Ft. Available data concerning T$_{1/2}$ and BR of $^{37}$K suffer from a lack of precision that will be easily reduced by a dedicated experiment.

  12. Double beta decay experiments

    International Nuclear Information System (INIS)

    The great sensitivity of double beta decay to neutrino mass and right handed currents has motivated many new and exciting attempts to observe this elusive nuclear phenomenon directly. Experiments in operation and other coming on line in the next one or two years are expected to result in order-of-magnitude improvements in detectable half lives for both the two-neutrino and no-neutrino modes. A brief history of double beta decay experiments is presented together with a discussion of current experimental efforts, including a gas filled time projection chamber being used to study selenium-82. (author)

  13. Neutrinoless Double Beta Decay

    CERN Document Server

    Päs, Heinrich

    2015-01-01

    We review the potential to probe new physics with neutrinoless double beta decay $(A,Z) \\to (A,Z+2) + 2 e^-$. Both the standard long-range light neutrino mechanism as well as short-range mechanisms mediated by heavy particles are discussed. We also stress aspects of the connection to lepton number violation at colliders and the implications for baryogenesis.

  14. Beta and muon decays

    International Nuclear Information System (INIS)

    These notes represent a series of lectures delivered by the authors in the Junta de Energia Nuclear, during the Spring term of 1965. They were devoted to graduate students interested in the Theory of Elementary Particles. Special emphasis was focussed into the computational problems. Chapter I is a review of basic principles (Dirac equation, transition probabilities, final state interactions.) which will be needed later. In Chapter II the four-fermion punctual Interaction is discussed, Chapter III is devoted to the study of beta-decay; the main emphasis is given to the deduction of the formulae corresponding to electron-antineutrino correlation, electron energy spectrum, lifetimes, asymmetry of electrons emitted from polarized nuclei, electron and neutrino polarization and time reversal invariance in beta decay. In Chapter IV we deal with the decay of polarized muons with radiative corrections. Chapter V is devoted to an introduction to C.V.C. theory. (Author)

  15. Bound beta-decay: BOB

    International Nuclear Information System (INIS)

    For many years exotic decay modes of the neutron have been investigated as possible doorways to the exploration of new physics. The bound beta-decay (BOB) of the neutron into a hydrogen atom and an anti-neutrino offers a very elegant method to study neutrino helicities. However, this rare decay has not yet been observed for the free neutron, owing to the challenge of measuring a decay involving only electrically neutral particles and with an estimated branching ratio of only a few 106 of the three-body decay mode. During the past few years scientists from the TUM E18 Group have developed a novel experimental scheme which addresses all necessary problems associated with the observation of this two-body neutron decay in a very coherent way. The BOB experiment shall be installed at a tangential beam tube of a powerful research reactor such as the SR6 at the FRMII in Garching or H6-H7 beam tube at ILL. This talk will provide insights and ideas on how such an experiment is to be performed.

  16. Beta decay for pedestrians

    CERN Document Server

    Lipkin, Harry Jeannot

    1962-01-01

    The ""pedestrian approach"" was developed to describe some essentially simple experimental results and their theoretical implications in plain language. In this graduate-level text, Harry J. Lipkin presents simply, but without oversimplification, the aspects of beta decay that can be understood without reference to the formal theory; that is, the reactions that follow directly from conservation laws and elementary quantum mechanics.The pedestrian treatment is neither a substitute for a complete treatment nor a watered-down version.

  17. Double beta decay: present status

    OpenAIRE

    Barabash, A. S.

    2008-01-01

    The present status of double beta decay experiments (including the search for $2\\beta^{+}$, EC$\\beta^{+}$ and ECEC processes) are reviewed. The results of the most sensitive experiments are discussed. Average and recommended half-life values for two-neutrino double beta decay are presented. Conservative upper limits on effective Majorana neutrino mass and the coupling constant of the Majoron to the neutrino are established as $ < 0.75$ eV and $ < 1.9 \\cdot 10^{-4}$, respectively. Proposals fo...

  18. Measurement of Prominent eta Decay Branching Fractions

    CERN Document Server

    López, A; Méndez, H; Ramírez, J; Ge, J Y; Miller, D H; Sanghi, B; Shipsey, I P J; Xin, B; Adams, G S; Anderson, M; Cummings, J P; Danko, I; Hu, D; Moziak, B; Napolitano, J; He, Q; Insler, J; Muramatsu, H; Park, C S; Thorndike, E H; Yang, F; Artuso, M; Blusk, S; Khalil, S; Li, J; Menaa, N; Mountain, R; Nisar, S; Randrianarivony, K; Sia, R; Skwarnicki, T; Stone, S; Wang, J C; Bonvicini, G; Cinabro, D; Dubrovin, M; Lincoln, A; Asner, D M; Edwards, K W; Naik, P; Briere, R A; Ferguson, T; Tatishvili, G; Vogel, H; Watkins, M E; Rosner, J L; Adam, N E; Alexander, J P; Cassel, D G; Duboscq, J E; Ehrlich, R; Fields, L; Galik, R S; Gibbons, L; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Mahlke-Krüger, H; Mohapatra, D; Onyisi, P U E; Patterson, J R; Peterson, D; Riley, D; Ryd, A; Sadoff, A J; Shi, X; Stroiney, S; Sun, W M; Wilksen, T; Athar, S B; Patel, R; Yelton, J; Rubin, P; Eisenstein, B I; Karliner, I; Lowrey, N; Selen, M; White, E J; Wiss, J; Mitchell, R E; Shepherd, M R; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Poling, R; Scott, A W; Zweber, P; Dobbs, S; Metreveli, Z; Seth, K K; Tomaradze, A G; Ernst, J; Ecklund, K M; Severini, H; Love, W; Savinov, V

    2007-01-01

    The decay psi(2S) --> eta J/psi is used to measure, for the first time, all prominent eta-meson branching fractions with the same experiment in the same dataset, thereby providing a consistent treatment of systematics across branching fractions. We present results for eta decays to gamma gamma, pi+pi-pi0, 3 pi0, pi+ pi- gamma, and e+ e- gamma, accounting for 99.9% of all eta decays. The precisions for several of the branching fractions and their ratios are improved. Two channels, pi+ pi- gamma and e+ e- gamma, show results that differ at the level of three standard deviations from those previously determined.

  19. Beta decay of 187Re and cosmochronology

    Science.gov (United States)

    Ashktorab, K.; Jänecke, J. W.; Becchetti, F. D.

    1993-06-01

    Uncertainties which limit the use of the 187-187Os isobaric pair as a cosmochronometer for the age of the galaxy and the universe include those of the partial half-lives of the continuum and bound-state decays of 187Re. While the total half-life of the decay is well established, the partial half-life for the continuum decay is uncertain, and several previous measurements are not compatible with each other. A high-temperature quartz proportional counter has been used in this work to remeasure the continuum decay of 187Re by introducing a metallo-organic rhenium compound into the counting gas. The measured beta end-point energy for the continuum decay of neutral 187Re to singly ionized 187Os of 2.70+/-0.09 keV agrees with earlier results. However, the present half-life measurement of (45+/-3) Gyr agrees within the quoted uncertainties only with the earlier measurement of Payne [Ph.D. thesis, University of Glasgow, 1965 (unpublished)] and Drever (private communication). The new half-life for the continuum decay and the total half-life of (43.5+/-1.3) Gyr, as reported by Linder et al. [Nature (London) 320, 246 (1986)] yield a branching ratio for the bound-state decay into discrete atomic states of (3+/-6)%. This is in agreement with the most recent calculated theoretical branching ratio of approximately 1%.

  20. Predicting Neutrinoless Double Beta Decay

    CERN Document Server

    Hirsch, M; Valle, J W F; Moral, A V; Ma, Ernest

    2005-01-01

    We give predictions for the neutrinoless double beta decay rate in a simple variant of the A_4 family symmetry model. We show that there is a lower bound for the neutrinoless double beta decay amplitude even in the case of normal hierarchical neutrino masses, corresponding to an effective mass parameter |m_{ee}| >= 0.17 \\sqrt{\\Delta m^2_{ATM}}. This result holds both for the CP conserving and CP violating cases. In the latter case we show explicitly that the lower bound on |m_{ee}| is sensitive to the value of the Majorana phase. We conclude therefore that in our scheme, neutrinoless double beta decay may be accessible to the next generation of high sensitivity experiments.

  1. Measurement of the eta decay branching ratio

    CERN Document Server

    Bargholtz, C; Bogoslawsky, D; Calén, H; Capellaro, F; Clement, H; Demirörs, L; Ekström, C; Fransson, K; Geren, L; Gustafsson, L; Höistad, Bo; Ivanov, G; Jacewicz, M; Jiganov, E; Johansson, T; Keleta, S; Koch, I; Kullander, Sven; Kupsc, A; Kuznetsov, A; Laukhin, I V; Lindberg, K; Marciniewski, P; Meier, R; Morosov, B; Oelert, W; Pauly, C; Pettersson, H; Petukhov, Yu P; Povtorejko, A; Ruber, Roger J M Y; Schönning, K; Scobel, W; Shafigullin, R; Shwartz, B; Skorodko, T Yu; Sopov, V; Stepaniak, J; Chernyshov, V; Tegnér, P E; Engblom, P T; Tikhomirov, V; Turowiecki, A; Wagner, G J; Wolke, M; Yamamoto, A; Zabierowski, J; Zartova, I; Zlomanczuk, Yu; Bargholtz, Chr.

    2007-01-01

    The reaction pd->3He eta at threshold was used to provide a clean source of eta mesons for decay studies with the WASA detector at CELSIUS. The branching ratio of the decay eta->pi+pi-e+e- is measured to be (4.6+/-1.4+/-0.5)x10^-4.

  2. Neutrinoless Double Beta Decay Experiments

    OpenAIRE

    Zuber, K.

    2014-01-01

    Neutrinoless double beta decay is the only process known so far able to test the neutrino intrinsic nature: its experimental observation would imply that the lepton number is violated by two units and prove that neutrinos have a Majorana mass components, being their own anti-particle. While several experiments searching for such a rare decay have been performed in the past, a new generation of experiments using different isotopes and techniques have recently released their results or are taki...

  3. Beta decay of 31Ar

    International Nuclear Information System (INIS)

    A complete study of 31Ar beta decay has been made by high-resolution charged-particle and gamma-ray spectroscopy. Beta-delayed radiation was detected by an array of three charged-particle detectors and a large-volume germanium detector. Fifteen new energy levels were discovered in 31Cl. The beta-strength distribution, measured to 14.5 MeV, is compared with a shell-model calculation in the full sd space. The quenching of the Gamow-Teller strength and the isospin impurity of the IAS in 31Cl are discussed. (orig.)

  4. Experiments on double beta decay

    Energy Technology Data Exchange (ETDEWEB)

    Busto, J. [Neuchatel Univ. (Switzerland). Inst. de Physique

    1996-11-01

    The Double Beta Decay, and especially ({beta}{beta}){sub 0{nu}} mode, is an excellent test of Standard Model as well as of neutrino physics. From experimental point of view, a very large number of different techniques are or have been used increasing the sensitivity of this experiments quite a lot (the factor of 10{sup 4} in the last 20 years). In future, in spite of several difficulties, the sensitivity would be increased further, keeping the interest of this very important process. (author) 4 figs., 5 tabs., 21 refs.

  5. Constraining neutrinoless double beta decay

    International Nuclear Information System (INIS)

    A class of discrete flavor-symmetry-based models predicts constrained neutrino mass matrix schemes that lead to specific neutrino mass sum-rules (MSR). We show how these theories may constrain the absolute scale of neutrino mass, leading in most of the cases to a lower bound on the neutrinoless double beta decay effective amplitude.

  6. Weak decays and double beta decay

    International Nuclear Information System (INIS)

    Work to measure the Σ+ 0 degree differential cross section in the reaction K-p → Σ+π- at several incident K- momenta between 600 and 800 MeV/c as well as the asymmetries in the decays of polarized Σ+'s into protons and neutral pions and of polarized Σ-'s into neutrons and negative pions in collaboration with experimenters from Yale, Brookhaven, and the University of Pittsburgh (Brookhaven experiment 702) has been completed. Data from this experiment is currently being analyzed at Yale. Work is currently underway to develop and construct an experiment to search for neutrinoless double beta decay in thin foils of Mo100 in collaboration with experimenters from Lawrence Berkeley Laboratory. Development work on the solid state silicon detectors should be complete in the next six months and construction should e well underway within the next year

  7. Pion beta decay at PILAC

    International Nuclear Information System (INIS)

    The proposal to build PILAC presents the possibility of making an improved measurement of the pion beta decay rate. The rate for the decay π+ → π0e+νe is predicted by the Standard Model (SM) to be R(π+ → π0e+νe) = 0.3999 ± 0.0005 s-1. The best experimental number, from LAMPF Experiment 32, using in-flight decays, is R(π+ → π0e+νe) = 0.394 ± 0.0015 s-1. A precise measurement would test the SM by testing the unitarity of the Cabibbo- Kobayashi-Maskawa matrix, for which one analysis of the nuclear beta decay data has shown a 0.4% discrepancy. Thus an experiment at the 0. 2% level would be a significant one. Detailed study of possible designs will be needed, as well as extensive testing of components. The reduction of systematic errors to the 0.1% level can only be done over a period of years with a highly stable apparatus and beam. At a minimum, three years of occupancy of a beam line, with 800 hours per year, would be required. 23 refs., 2 figs., 2 tabs

  8. Trapped-ion decay spectroscopy towards the determination of ground-state components of double-beta decay matrix elements

    CERN Document Server

    Brunner, T; Andreoiu, C; Brodeur, M; Delheji, P; Ettenauer, S; Frekers, D; Gallant, A T; Gernhäuser, R; Grossheim, A; Krücken, R; Lennarz, A; Lunney, D; Mücher, D; Ringle, R; Simon, M C; Simon, V V; Sjue, S K L; Zuber, K; Dilling, J

    2013-01-01

    A new technique has been developed at TRIUMF's TITAN facility to perform in-trap decay spectroscopy. The aim of this technique is to eventually measure weak electron capture branching ratios (ECBRs) and by this to consequently determine GT matrix elements of $\\beta\\beta$ decaying nuclei. These branching ratios provide important input to the theoretical description of these decays. The feasibility and power of the technique is demonstrated by measuring the ECBR of $^{124}$Cs.

  9. Trapped-ion decay spectroscopy towards the determination of ground-state components of double-beta decay matrix elements

    Energy Technology Data Exchange (ETDEWEB)

    Brunner, T. [TRIUMF, Vancouver (Canada); Technische Universitaet Muenchen, Physik Department E12, Garching (Germany); Lapierre, A.; Delheji, P.; Grossheim, A.; Ringle, R.; Simon, M.C.; Sjue, S.K.L. [TRIUMF, Vancouver (Canada); Andreoiu, C. [Simon Fraser University, Department of Chemistry, Burnaby (Canada); Brodeur, M. [University of Notre Dame, Department of Physics, Notre Dame, IN (United States); Ettenauer, S.; Gallant, A.T.; Dilling, J. [TRIUMF, Vancouver (Canada); University of British Columbia, Department of Physics and Astronomy, Vancouver (Canada); Frekers, D. [Westfaelische Wilhelms-Universitaet Muenster, Muenster (Germany); Gernhaeuser, R.; Kruecken, R.; Muecher, D. [Technische Universitaet Muenchen, Physik Department E12, Garching (Germany); Lennarz, A. [TRIUMF, Vancouver (Canada); Westfaelische Wilhelms-Universitaet Muenster, Muenster (Germany); Lunney, D. [Universite de Paris Sud, CSNSM-IN2P3-CNRS, Orsay (France); Simon, V.V. [TRIUMF, Vancouver (Canada); Ruprecht-Karls-Universitaet Heidelberg, Fakulaet fuer Physik und Astronomie, Heidelberg (Germany); Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Zuber, K. [Technische Universitaet Dresden, Institut fuer Kern- und Teilchenphysik, Dresden (Germany)

    2013-11-15

    A new technique has been developed at the TRIUMF's TITAN facility to perform in-trap decay spectroscopy. The aim of this technique is to eventually measure weak electron capture branching ratios (ECBRs) and by this to consequently determine GT matrix elements of {beta} {beta} decaying nuclei. These branching ratios provide important input to the theoretical description of these decays. The feasibility and power of the technique is demonstrated by measuring the ECBR of {sup 124}Cs. (orig.)

  10. Tables of double beta decay data

    Energy Technology Data Exchange (ETDEWEB)

    Tretyak, V.I. [AN Ukrainskoj SSR, Kiev (Ukraine)]|[Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires; Zdesenko, Y.G. [AN Ukrainskoj SSR, Kiev (Ukraine)

    1995-12-31

    A compilation of experimental data on double beta decay is presented. The tables contain the most stringent known experimental limits or positive results of 2{beta} transitions of 69 natural nuclides to ground and excited states of daughter nuclei for different channels (2{beta}{sup -}; 2{beta}{sup +}; {epsilon}{beta}{sup +}; 2{epsilon}) and modes (0{nu}; 2{nu}; 0{nu}M) of decay. (authors). 189 refs., 9 figs., 3 tabs.

  11. HALF-LIVES OF LONG-LIVED ALPHA DECAY, BETA DECAY, ELECTRON CAPTURE DECAY, BETA BETA-DECAY, PROTON DECAY AND SPONTANEOUS FISSION DECAY NUCLIDES.

    Energy Technology Data Exchange (ETDEWEB)

    HOLDEN, H.E.

    2003-08-08

    In his review of radionuclides for dating purposes, Roth noted that there were a large number of nuclides, normally considered ''stable'' but which are radioactive with a very long half-life. Roth suggested that I review the data on the half-life values of these long-lived nuclides for the 2001 Atomic Weights Commission meeting in Brisbane. I provided a report, BNL-NCS-68377, to fulfill Roth's request. Peiser has now made a similar suggestion that I review these data for our next Commission meeting in Ottawa for their possible inclusion in our Tables. These half-life values for long-lived nuclides include those due to various decay modes, {alpha}-decay, {beta}-decay, electron capture decay, {beta}{beta}-decay, proton decay and spontaneous fission decay. This data review (post Brisbane) provides an update to the recommendation of the 2001 review.

  12. Branching Fraction Measurement of B to omega l nu decays

    Energy Technology Data Exchange (ETDEWEB)

    Lees, J.P.; Poireau, V.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Palano, A.; /Bari U. /INFN, Bari; Eigen, G.; Stugu, B.; /Bergen U.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; /LBL, Berkeley /UC, Berkeley; Koch, H.; Schroeder, T.; /Ruhr U., Bochum; Asgeirsson, D.J.; Hearty, C.; Mattison, T.S.; McKenna, J.A.; So, R.Y.; /British Columbia U.; Khan, A.; /Brunel U.; Blinov, V.E.; /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Indian Inst. Tech., Guwahati /Harvard U. /Harvey Mudd Coll. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U., Comp. Sci. Dept. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Naples U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U.; /more authors..

    2012-06-13

    We present a measurement of the B{sup +} {yields} {omega}{ell}{sup +}{nu} branching fraction based on a sample of 467 million B{bar B} pairs recorded by the BABAR detector at the SLAC PEP-II e{sup +}e{sup -} collider. We observe 1041 {+-} 133 signal decays, corresponding to a branching fraction of {Beta}(B{sup +} {yields} {omega}{ell}{sup +}{nu}) = (1.15 {+-} 0.15 {+-} 0.12) x 10{sup -4}, where the first error is statistical and the second is systematic. The dependence of the decay rate on q{sup 2}, the momentum transfer squared to the lepton system, is compared to QCD predictions of the form factors based on a quark model and light-cone sum rules.

  13. Experiments on double beta decay

    International Nuclear Information System (INIS)

    The Double Beta Decay, and especially (ββ)0ν mode, is an excellent test of Standard Model as well as of neutrino physics. From experimental point of view, a very large number of different techniques are or have been used increasing the sensitivity of this experiments quite a lot (the factor of 104 in the last 20 years). In future, in spite of several difficulties, the sensitivity would be increased further, keeping the interest of this very important process. (author) 4 figs., 5 tabs., 21 refs

  14. Theoretical aspects of double beta decay

    International Nuclear Information System (INIS)

    Considerable effort has been expended recently in theoretical studies of double beta decay. Much of this work has focussed on the constraints this process places on gauge theories of the weak interaction, in general, and on the neutrino mass matrix, in particular. In addition, interesting nuclear structure questions have arisen in studies of double beta decay matrix elements. After briefly reviewing the theory of double beta decay, some of the progress that has been made in these areas is summarized. 25 references

  15. Challenges in Double Beta Decay

    Directory of Open Access Journals (Sweden)

    Oliviero Cremonesi

    2014-01-01

    Full Text Available In the past ten years, neutrino oscillation experiments have provided the incontrovertible evidence that neutrinos mix and have finite masses. These results represent the strongest demonstration that the electroweak Standard Model is incomplete and that new Physics beyond it must exist. In this scenario, a unique role is played by the Neutrinoless Double Beta Decay searches which can probe lepton number conservation and investigate the Dirac/Majorana nature of the neutrinos and their absolute mass scale (hierarchy problem with unprecedented sensitivity. Today Neutrinoless Double Beta Decay faces a new era where large-scale experiments with a sensitivity approaching the so-called degenerate-hierarchy region are nearly ready to start and where the challenge for the next future is the construction of detectors characterized by a tonne-scale size and an incredibly low background. A number of new proposed projects took up this challenge. These are based either on large expansions of the present experiments or on new ideas to improve the technical performance and/or reduce the background contributions. In this paper, a review of the most relevant ongoing experiments is given. The most relevant parameters contributing to the experimental sensitivity are discussed and a critical comparison of the future projects is proposed.

  16. Neutrino mass, neutrinoless double electron capture and rare beta decays

    Energy Technology Data Exchange (ETDEWEB)

    Mustonen, M T; Suhonen, J, E-mail: jouni.suhonen@phys.jyu.f [Department of Physics, PO Box 35 (YFL), FI-40014 University of Jyvaeskylae (Finland)

    2010-01-01

    We present results of our theoretical calculations on three nuclei of interest from the neutrino-physics point of view: Firstly, we present the second-forbidden decay branch of {sup 115}In with the ultra-low Q value and theoretical open questions related to such decays. Secondly, we have calculated estimates for the half-lives of the single-beta decay channels of {sup 96}Zr and concluded that the possible contamination from those to the geochemical measurements of {sup 96}Zr double-beta-decay half-life is rather small. Thirdly, we have taken a look at the neutrinoless resonance double-electron-capture decay of {sup 112}Sn in the light of recent JYFLTRAP Q value measurements and discovered that the badly fulfilled resonance condition renders the decay unobservable.

  17. Beta-decay properties of $^{25}$Si and $^{26}$P

    CERN Document Server

    Thomas, J C; Äystö, J; Béraud, R; Blank, B; Canchel, G; Czajkowski, S; Dendooven, P; Ensallem, A; Giovinazzo, J; Guillet, N; Honkanen, J; Jokinen, A; Laird, A M; Lewitowicz, M; Longour, C; De Santos, F O; Peräjärvi, K; democrite-00023307, ccsd

    2004-01-01

    The $\\beta$-decay properties of the neutron-deficient nuclei $^{25}$Si and $^{26}$P have been investigated at the GANIL/LISE3 facility by means of charged-particle and $\\gamma$-ray spectroscopy. The decay schemes obtained and the Gamow-Teller strength distributions are compared to shell-model calculations based on the USD interaction. B(GT) values derived from the absolute measurement of the $\\beta$-decay branching ratios give rise to a quenching factor of the Gamow-Teller strength of 0.6. A precise half-life of 43.7 (6) ms was determined for $^{26}$P, the $\\beta$- (2)p decay mode of which is described.

  18. Broad resonances and beta-decay

    DEFF Research Database (Denmark)

    Riisager, K.; Fynbo, H. O. U.; Hyldegaard, S.;

    2015-01-01

    Beta-decay into broad resonances gives a distorted lineshape in the observed energy spectrum. Part of the distortion arises from the phase space factor, but we show that the beta-decay matrix element may also contribute. Based on a schematic model for p-wave continuum neutron states it is argued...

  19. $\\beta$-decay study of $^{77}$Cu

    CERN Document Server

    Patronis, N; Górska, M; Huyse, M; Kruglov, K; Pauwels, D; Van de Vel, K; Van Duppen, P; Van Roosbroeck, J; Thomas, J-C; Franchoo, S; Cederkäll, J; Fedosseev, V; Fynbo, H; Georg, U; Jonsson, O; Köster, U; Materna, T; Mathieu, L; Serot, O; Weissman, L; Müller, W F; Mishin, V I; Fedorov, D

    2009-01-01

    A beta-decay study of Cu-77 has been performed at the ISOLDE mass separator with the aim to deduce its beta-decay properties and to obtain spectroscopic information on Zn-77. Neutron-rich copper isotopes were produced by means of proton- or neutron-induced fission reactions on U-238. After the production, Cu-77 was selectively laser ionized, mass separated and sent to different detection systems where beta-gamma and beta-n coincidence data were collected. We report on the deduced half-live, decay scheme, and possible spin assignment of 77Cu.

  20. Beta decay of highly charged ions

    International Nuclear Information System (INIS)

    Ion storage rings and ion traps provide the very first opportunity to address nuclear beta decay under conditions prevailing in hot stellar plasmas during nucleosynthesis, i.e. at high atomic charge states. Experiments are summarized that were performed in this field during the last decade at the ion storage-cooler ring ESR in Darmstadt. Special emphasis is given to the first observation of bound-state beta decay, where the created electron remains bound in an inner orbital of the daughter atom. The impact of this specific 'stellar' decay mode for s-process nucleosynthesis as well as for nuclear 'eon clocks' is outlined. Finally, a new technique, single-ion decay spectroscopy, is presented, where one observes two-body beta decay characteristics (i.e. orbital electron capture or bound-state beta decay) of highly charged, single ions for well-defined nuclear and atomic quantum states of both the mother - and the daughter - ion.

  1. First forbidden beta decay in light nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Millener, D.J.; Warburton, E.K.

    1984-01-01

    Beta decay matrix elements for the operators sigma dot del and sigma dot r are calculated for eight J/sup +/ ..-->.. J/sup -/ or J/sup -/ ..-->.. J/sup +/ beta transitions. Results using harmonic oscillator wave functions differ markedly from those using more realistic Woods-Saxon wave functions. A substantial contribution to the sigma dot del matrix elements from pion exchange currents is required to reproduce the experimental beta decay rates. 15 references.

  2. First forbidden beta decay in light nuclei

    International Nuclear Information System (INIS)

    Beta decay matrix elements for the operators sigma dot del and sigma dot r are calculated for eight J+ → J- or J- → J+ beta transitions. Results using harmonic oscillator wave functions differ markedly from those using more realistic Woods-Saxon wave functions. A substantial contribution to the sigma dot del matrix elements from pion exchange currents is required to reproduce the experimental beta decay rates. 15 references

  3. Double beta decay: A theoretical overview

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, S.P.

    1988-01-01

    This paper reviews the theoretical possibility of double beta decay. The titles of the main sections of this paper are: Nuclear physics setting; Particle physics requirements; Kinematical features of the decay modes; Nuclear matrix elements; the Shell model and two-neutrino decay; Quasi-particle random phase approximation; and Future considerations. 18 refs., 7 tabs. (LSP)

  4. The search for neutrinoless double beta decay

    CERN Document Server

    Gomez-Cadenas, J J; Mezzetto, M; Monrabal, F; Sorel, M

    2011-01-01

    In the last few years the search for neutrinoless double beta decay has evolved from being almost a marginal activity in neutrino physics to one of the highest priorities for understanding neutrinos and the origin of mass. There are two main reasons for this paradigm shift: the discovery of neutrino oscillations, which clearly established the existence of massive neutrinos; and the existence of an unconfirmed, but not refuted, claim of evidence for neutrinoless double decay in 76Ge. As a consequence, a new generation of experiments, employing different detection techniques and {\\beta}{\\beta} isotopes, is being actively promoted by experimental groups across the world. In addition, nuclear theorists are making remarkable progress in the calculation of the neutrinoless double beta decay nuclear matrix elements, thus eliminating a substantial part of the theoretical uncertainties affecting the particle physics interpretation of this process. In this report, we review the main aspects of the double beta decay pro...

  5. Neutron bound beta-decay: BOB

    International Nuclear Information System (INIS)

    An experiment to observe the bound beta-decay (BOB) of the free neutron into a hydrogen atom and an electron anti-neutrino is described. The hyperfine spin state population of the monoenergetic hydrogen atom yields the neutrino left-handedness or possible right-handed admixture as well as possible small scalar and tensor contributions to the weak force. The BOB H(2s) hyperfine states can be separated with a Lamb-Shift Spin Filter. These monoenergetic H(2s) atoms are ionised into H− by charge exchanging within an argon cell. These ions are then separated using an adaptation of a MAC-E Filter. A first experiment is proposed at the FRMII high thermal-neutron flux beam reactor SR6 through-going beam tube, where we will seek to observe this rare neutron decay-mode for the first time and determine the branching ratio. After successful completion, the hyperfine spin state population will be determined, possibly at the ILL high-flux beam reactor through-going beam tube H6–H7, where the thermal neutron flux is a factor of four larger.

  6. Neutron bound {beta}- decay- BOB

    Energy Technology Data Exchange (ETDEWEB)

    Gabriel, M.; Berger, M.; Emmerich, R.; Faestermann, T.; Gutsmiedl, E.; Hartmann, F.J.; Paul, S.; Ruschel, S.; Schoen, J.; Schott, W.; Schubert, U.; Trautner, A. [Physik-Department, TUM, 85748 Garching (Germany); Engels, R. [Institut fuer Kernphysik, Forschungszentrum Juelich, 52425 Juelich (Germany); Fierlinger, P. [Excellence Cluster Universe, TUM, 85748 Garching (Germany); Hertenberger, R. [Sektion Physik, LMU, 85748 Garching (Germany); Roehrmoser, R. [FRM2, TUM, 85748 Garching (Germany); Udem, T. [Max-Planck-Institut fuer Quantenphysik, 85748 Garching (Germany)

    2011-07-01

    The bound neutron {beta}-decay(BOB) into a hydrogen atom and an electron antineutrino is investigated.The hyper-fine-state population of the monoenergetic hydrogen atoms (326.3 eV) yields the neutrino left-handed-ness or a possible right-handed admixture and possible small scalar and tensor contributions to the weak force. Preexperiments to measure the BOB H(2s) atoms have been done or are being set up using ionizer and RF discharge proton sources, a Wien filter, Cs and Ar cells, a spin filter, electric counter and accelerating fields, a double focusing magnet and a solar blind PM for the Lyman-{alpha} photons. In a first experiment, the charge exchange of the H(2s) atoms into H{sup -}, offering a selective method to discriminate these states against background, is investigated. In a second step the number of background H(2s) resulting from protons interacting with the walls of the experimental setup are determined. For this a quenching E field and a solar blind PM are used.

  7. Falsifying Baryogenesis with Neutrinoless Double Beta Decay

    CERN Document Server

    Graf, Lukas

    2016-01-01

    We discuss the relation between lepton number violation at high and low energies, particularly, the constraints on baryogenesis models, which would be implied by an observation of neutrinoless double beta decay. The primordial baryon asymmetry can be washed out by effective lepton number violating operators triggering neutrinoless double beta decay in combination with sphaleron processes. A generic conclusion is that popular models of baryogenesis are excluded if a non-standard mechanism of neutrinoless double beta decay, i.e., other than the standard light neutrino exchange, is observed. Apart from the effective field approach, we also outline the possible extension of our arguments to a general UV-completed model.

  8. Review of modern double beta decay experiments

    Science.gov (United States)

    Barabash, A. S.

    2015-10-01

    The review of modern experiments on search and studying of double beta decay processes is done. Results of the most sensitive current experiments are discussed. The main attention is paid to EXO-200, KamLAND-Zen, GERDA-I and CUORE-0 experiments. Modern values of T1/2(2ν) and best present limits on neutrinoless double beta decay and double beta decay with Majoron emission are presented. Conservative limits on effective mass of a Majorana neutrino ( at the level of ˜ 0.01-0.1 eV are discussed.

  9. Precision study of the $\\beta$-decay of $^{74}$Rb

    CERN Multimedia

    Van Duppen, P L E; Lunney, D

    2002-01-01

    We are proposing a high-resolution study of the $\\beta$-decay of $^{74}$Rb in order to extrapolate our precision knowledge of the superallowed $\\beta$-decays from the sd and fp shells towards the medium-heavy Z=N nuclei. The primary goal is to provide new data for testing the CVC hypothesis and the unitarity condition of the CKM matrix of the Standard Model. The presented programme would involve the careful measurements of the decay properties of $^{74}$Rb including the branching ratios to the excited states as well as the precise determination of the decay energy of $^{74}$Rb. The experimental methods readily available at ISOLDE include high-transmission conversion electron spectroscopy, $\\gamma$-ray spectroscopy as well as the measurements of the masses of $^{74}$Rb and $^{74}$Kr using two complementary techniques, ISOLTRAP and MISTRAL. The experiment would rely on a high-quality $^{74}$Rb beam available at ISOLDE with adequate intensity.

  10. Review of modern double beta decay experiments

    International Nuclear Information System (INIS)

    The review of modern experiments on search and studying of double beta decay processes is done. Results of the most sensitive current experiments are discussed. The main attention is paid to EXO-200, KamLAND-Zen, GERDA-I and CUORE-0 experiments. Modern values of T1/2(2ν) and best present limits on neutrinoless double beta decay and double beta decay with Majoron emission are presented. Conservative limits on effective mass of a Majorana neutrino (〈mν〉 < 0.46 eV) and a coupling constant of Majoron to neutrino (〈gee〉 < 1.3 · 10−5) are obtained. Prospects of search for neutrinoless double beta decay in new experiments with sensitivity to 〈mν〉 at the level of ∼ 0.01-0.1 eV are discussed

  11. Neutrino potential for neutrinoless double beta decay

    CERN Document Server

    Iwata, Yoritaka

    2016-01-01

    Neutrino potential for neutrinoless double beta decay is studied with focusing on its statistical property. The statistics provide a gross view of understanding amplitude of constitutional components of the nuclear matrix element.

  12. Review of modern double beta decay experiments

    Energy Technology Data Exchange (ETDEWEB)

    Barabash, A. S., E-mail: barabash@itep.ru [Institute of Theoretical and Experimental Physics (NRC ”Kurchatov Institute”), B. Cheremushkinskaya 25, Moscow (Russian Federation)

    2015-10-28

    The review of modern experiments on search and studying of double beta decay processes is done. Results of the most sensitive current experiments are discussed. The main attention is paid to EXO-200, KamLAND-Zen, GERDA-I and CUORE-0 experiments. Modern values of T{sub 1/2}(2ν) and best present limits on neutrinoless double beta decay and double beta decay with Majoron emission are presented. Conservative limits on effective mass of a Majorana neutrino (〈m{sub ν}〉 < 0.46 eV) and a coupling constant of Majoron to neutrino (〈g{sub ee}〉 < 1.3 · 10{sup −5}) are obtained. Prospects of search for neutrinoless double beta decay in new experiments with sensitivity to 〈m{sub ν}〉 at the level of ∼ 0.01-0.1 eV are discussed.

  13. Searches for neutrinoless double beta decay

    Science.gov (United States)

    Schwingenheuer, Bernhard

    2012-07-01

    Neutrinoless double beta decay is a lepton number violating process whose observation would also establish that neutrinos are their own anti-particles. There are many experimental efforts with a variety of techniques. Some (EXO, Kamland-Zen, GERDA phase I and CANDLES) started take data in 2011 and EXO has reported the first measurement of the half life for the double beta decay with two neutrinos of 136Xe. The sensitivities of the different proposals are reviewed.

  14. Searches for neutrinoless double beta decay

    CERN Document Server

    Schwingenheuer, B

    2012-01-01

    Neutrinoless double beta decay is a lepton number violating process whose observation would also establish that neutrinos are their own anti-particles. There are many experimental efforts with a variety of techniques. Some (EXO, Kamland-Zen, GERDA phase I and CANDLES) started take data in 2011 and EXO has reported the first measurement of the half life for the double beta decay with two neutrinos of $^{136}$Xe. The sensitivities of the different proposals are reviewed.

  15. Nuclear physics issues in double beta decay

    International Nuclear Information System (INIS)

    A number of issues in double beta decay are discussed: shell model estimates of 2nu matrix elements, a sum rule for the double Gamow-Teller operator, a comparison of shell model and quasiparticle RPA results, Pontecorvo's Te ratio argument, neutrinoless ββ decay mediated by heavy neutrinos, and the structure of O+ states in Ge isotopes. 24 refs., 3 figs

  16. Precision Study of the $\\beta$-decay of $^{62}$Ga

    CERN Multimedia

    2002-01-01

    It is proposed to perform a precision study of the $\\beta$-decay of $\\,^{62}$Ga taking advantage of recent developments of the ISOLDE Laser Ion Source. The goal is to eventually extend the high-precision knowledge of superallowed $\\beta$-decays beyond the nine decays that presently are used for extracting the V$_{ud}$ quark mixing matrix element of the CKM matrix. The scientific motivations are the current deviation of more than 2$\\sigma$ of the unitary condition of this matrix, which could be an indication of non-standard-model physics, and a test of the theoretical corrections applied to the experimental data. The experiment will utilise the Total Absorption $\\gamma$-ray (TAG) spectrometer in order to determine weak branchings to excited states in $^{62}$Zn and the ISOLDE spectroscopy station to perform half-life measurements and detailed spectroscopy of this nucleus.

  17. Exponential decay of Laplacian eigenfunctions in domains with branches

    CERN Document Server

    Delitsyn, Andrey; Grebenkov, Denis S

    2011-01-01

    The behavior of Laplacian eigenfunctions in domains with branches is investigated. If an eigenvalue is below a threshold which is determined by the shape of the branch, the associated eigenfunction is proved to exponentially decay inside the branch. The decay rate is twice the square root of the difference between the threshold and the eigenvalue. The derived exponential estimate is applicable for arbitrary domains in any spatial dimension. Numerical simulations illustrate and further extend the theoretical estimate.

  18. Exponential decay of Laplacian eigenfunctions in domains with branches

    OpenAIRE

    Delitsyn, Andrey; Nguyen, Binh-Thanh; Grebenkov, Denis S.

    2011-01-01

    The behavior of Laplacian eigenfunctions in domains with branches is investigated. If an eigenvalue is below a threshold which is determined by the shape of the branch, the associated eigenfunction is proved to exponentially decay inside the branch. The decay rate is twice the square root of the difference between the threshold and the eigenvalue. The derived exponential estimate is applicable for arbitrary domains in any spatial dimension. Numerical simulations illustrate and further extend ...

  19. Recent double beta decay results

    Energy Technology Data Exchange (ETDEWEB)

    Balysh, A. (Kurchatov Institute, 123 182 Moscow (Russian Federation)); Beck, M. (Max-Planck-Institut fuer Kernphysik, W-6900 Heidelberg (Germany)); Belyaev, S.T. (Kurchatov Institute, 123 182 Moscow (Russian Federation)); Bensch, F.; Bockholt, J. (Max-Planck-Institut fuer Kernphysik, W-6900 Heidelberg (Germany)); Demehin, A.; Gurov, A. (Kurchatov Institute, 123 182 Moscow (Russian Federation)); Heusser, G.; Hirsch, M.; Klapdor-Kleingrothaus, H.V. (Max-Planck-Institut fuer Kernphysik, W-6900 Heidelberg (Germany)); Kondratenko, I.; Lebedev, V.I. (Kurchatov Institute, 123 182 Moscow (Russian Federation)); Maier, B. (Max-Planck-Institut fuer Kernphysik, W-6900 Heidelberg (Germany)); Mueller, A. (Istituto Nazionale di Fisica Nucleare LNGS, 67010 Assergi (Italy)); Petry, F.; Piepke, A.; Strecker, H.; Voellinger, M.; Zuber, K. (Max-Planck-Institut fuer Kernphysik, W-6900 Heidelberg (Germany))

    1992-02-01

    The status and recent results of second generation [beta][beta]-experiments using isotopically enriched source materials are described. These experiments are at present the most sensitive tools to distinguish Dirac from Majorana neutrinos. The at present most advanced experimental techniques, namely the use of high-resolution calorimetric detectors and of time projection chambers are compared. New limits on the Majorana neutrino mass as well as for the Majoron-neutrino coupling are presented.

  20. Branching ratios for the decay of d{sup *}(2380)

    Energy Technology Data Exchange (ETDEWEB)

    Bashkanov, M. [University of Edinburgh, School of Physics and Astronomy, Edinburgh (United Kingdom); Eberhard-Karls-Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); University of Tuebingen, Kepler Center for Astro and Particle Physics, Tuebingen (Germany); Clement, H. [Eberhard-Karls-Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); University of Tuebingen, Kepler Center for Astro and Particle Physics, Tuebingen (Germany); Skorodko, T. [Tomsk State University, Department of Physics, Tomsk (Russian Federation)

    2015-07-15

    Based on measurements, the branching ratios for the decay of the recently discovered dibaryon resonance d{sup *}(2380) into two-pion production channels and into the np channel are evaluated. Possibilities for a decay into the isoscalar single-pion channel are discussed. Finally, the electromagnetic decay of d{sup *}(2380) is considered. (orig.)

  1. Neutrinoless double beta decay from lattice QCD

    CERN Document Server

    Nicholson, Amy; Chang, Chia Cheng; Clark, M A; Joo, Balint; Kurth, Thorsten; Rinaldi, Enrico; Tiburzi, Brian; Vranas, Pavlos; Walker-Loud, Andre

    2016-01-01

    While the discovery of non-zero neutrino masses is one of the most important accomplishments by physicists in the past century, it is still unknown how and in what form these masses arise. Lepton number-violating neutrinoless double beta decay is a natural consequence of Majorana neutrinos and many BSM theories, and many experimental efforts are involved in the search for these processes. Understanding how neutrinoless double beta decay would manifest in nuclear environments is key for understanding any observed signals. In these proceedings we present an overview of a set of one- and two-body matrix elements relevant for experimental searches for neutrinoless double beta decay, describe the role of lattice QCD calculations, and present preliminary lattice QCD results.

  2. Double-Beta Decay at TUNL

    Science.gov (United States)

    Kidd, Mary

    2007-10-01

    Studying double-beta decay at Triangle Universities Nuclear Laboratory (TUNL) is perhaps one of the most promising ways to pinpoint the neutrino mass. What they do not mention is that to study double-beta decay, you probably have to become a certified miner, and if you have a fear of goats, you should stay away. In this talk, I will tell you some of my experiences as a TUNL graduate student, and how I am now nearly qualified for a job in the mining industry.

  3. Microscopic calculations for rare beta decays

    OpenAIRE

    Mustonen, Mika

    2010-01-01

    In this thesis consisting of six publications and an overview part, three cases of rare beta decays are studied using microscopic nuclear models. Firstly, the half-lives and electron spectra of 113Cd and 115In fourth-forbidden nonunique ground-state-to-ground-state beta decays are studied using two closely related nuclear models: The microscopic quasiparticle-phonon model (MQPM) and the proton-neutron MQPM (pnMQPM), which has been developed as a part of this thesis work. Our...

  4. Nuclear beta decay after Les Houches

    International Nuclear Information System (INIS)

    Wilkinson's 1977 Les Houches lectures summarized in detail how nuclear beta decay can be used to investigate fundamental nuclear phenomena and the achievements of this utilization up to that time. In this short talk the subsequent activity is briefly summarized and one area of high activity, namely first-forbidden beta decay, is singled out for more lengthy discussion. Specifically, the subject of interest is the very large meson exchange contribution to the time-like component of the axial current and the efforts to isolate this enhancement by means of careful shell-model calculations. 19 refs., 4 figs., 2 tabs

  5. Why search for double beta decay?

    International Nuclear Information System (INIS)

    Searching for neutrinoless double beta decay is the only known practical method for trying to determine whether neutrinos are their own antiparticles. The theoretical motivation for supposing that they may indeed be their own antiparticles is described. The reason that it is so difficult to ascertain experimentally whether they are or are not is explained, as is the special sensitivity of neutrinoless double beta decay. The potential implications of the observation of this reaction for neutrino mass and for the physics of neutrinos is discussed

  6. Helicity and nuclear $\\beta$ decay correlations

    CERN Document Server

    Hong, Ran; García, Alejandro

    2016-01-01

    We present simple derivations of nuclear $\\beta$-decay correlations with an emphasis on the special role of helicity. This provides a good opportunity to teach students about helicity and chirality in particle physics through exercises using simple aspects of quantum mechanics. In addition, this paper serves as an introduction to nuclear $\\beta$-decay correlations from both a theoretical and experimental vantage. This article can be used to introduce students to ongoing experiments searching for hints of new physics in the low-energy precision frontier.

  7. Tables of double beta decay data

    International Nuclear Information System (INIS)

    A compilation of experimental data on double beta decay is presented. The tables contain the most stringent known experimental limits or positive results of 2β transitions of 69 natural nuclides to ground and excited states of daughter nuclei for different channels (2β-; 2β+; εβ+; 2ε) and modes (0ν; 2ν; 0νM) of decay. (authors). 189 refs., 9 figs., 3 tabs

  8. Electron capture decay of {sup 116}In and nuclear structure of double {beta} decays

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, M.; Garcia, A.; Ortiz, C.E.; Kaloskamis, N.I. [University of Notre Dame, Notre Dame, Indiana 46556 (United States); Hindi, M.M. [Physics Department, Tennessee Technological University, Cookeville, Tennessee 38505 (United States); Norman, E.B. [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Davids, C.N. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Civitarese, O. [Department of Physics, University of La Plata, C. C. 67, 1900-La Plata (Argentina); Suhonen, J. [Department of Physics, University of Jyvaeskylae, P.O. Box 35, SF-40351, Jyvaeskylae (Finland)

    1998-08-01

    Quasiparticle-random-phase-approximation (QRPA) calculations of double {beta} decays have not been able to reproduce data in the A=100 system. We propose the A=116 system{emdash}because of its smaller deformation{emdash}as a simpler system to test QRPA calculations. We present results of two experiments we performed, which determine the electron-capture-decay branch of {sup 116}In to be (2.27{plus_minus}0.63){times}10{sup {minus}2}{percent}, from which we deduce logft=4.39{sub {minus}0.15}{sup +0.10}. We present QRPA calculations and compare their predictions to experimental data. Finally we use these calculations to predict the 2{nu} double-{beta}-decay rate of {sup 116}Cd to the ground and excited states of {sup 116}Sn. {copyright} {ital 1998} {ital The American Physical Society}

  9. Symmetry violations in nuclear and neutron $\\beta$ decay

    CERN Document Server

    Vos, K K; Timmermans, R G E

    2015-01-01

    The role of $\\beta$ decay as a low-energy probe of physics beyond the Standard Model is reviewed. Traditional searches for deviations from the Standard Model structure of the weak interaction in $\\beta$ decay are discussed in the light of constraints from the LHC and the neutrino mass. Limits on the violation of time-reversal symmetry in $\\beta$ decay are compared to the strong constraints from electric dipole moments. Novel searches for Lorentz symmetry breaking in the weak interaction in $\\beta$ decay are also included, where we discuss the unique sensitivity of $\\beta$ decay to test Lorentz invariance. We end with a roadmap for future $\\beta$-decay experiments.

  10. Imperfect World of beta beta-decay Nuclear Data Sets

    Energy Technology Data Exchange (ETDEWEB)

    Pritychenko, B. [Brookhaven National Lab. (BNL), Upton, NY (United States). NNDC

    2015-01-03

    The precision of double-beta ββ-decay experimental half lives and their uncertainties is reanalyzed. The method of Benford's distributions has been applied to nuclear reaction, structure and decay data sets. First-digit distribution trend for ββ-decay T2v1/2 is consistent with large nuclear reaction and structure data sets and provides validation of experimental half-lives. A complementary analysis of the decay uncertainties indicates deficiencies due to small size of statistical samples, and incomplete collection of experimental information. Further experimental and theoretical efforts would lead toward more precise values of-decay half-lives and nuclear matrix elements.

  11. Double-beta decay in gauge theories

    International Nuclear Information System (INIS)

    The double-beta decay in gauge theories is considered. The review of the 76Ge, 82Se, 96Zr, 100Cd, 128Te, 130Te, 136Xe and 150Nd experimental nuclear targets is presented. The mechanism of the Majorana intermediate neutrino is considered. The R-parity of the violation of the contribution to the 0νββ decay is studied. The effective nucleon currents in dependence on the momentum are discussed. The extraction of the lepton number, violating the double-β decay parameters is presented

  12. Semiconductor detectors and double beta decay

    International Nuclear Information System (INIS)

    The underlying theory of double beta decay is discussed as well as some experimental observations. A class of second generation 76Ge detector experiments is then discussed. The design and physics considerations involved in the system used by LBL are explained, particularly the means of rejecting background activity. 24 references, 18 figures, 3 tables

  13. LHC dijet constraints on double beta decay

    CERN Document Server

    Helo, J C

    2015-01-01

    We use LHC dijet data to derive constraints on neutrinoless double beta decay. Upper limits on cross sections for the production of "exotic" resonances, such as a right-handed W boson or a diquark, can be converted into lower limits on the double beta decay half-life for fixed choices of other parameters. Constraints derived from run-I data are already surprisingly strong and complementary to results from searches using same-sign dileptons plus jets. For the case of the left-right symmetric model, in case no new resonance is found in future runs of the LHC and assuming $g_L=g_R$, we estimate a lower limit on the double beta decay half-live larger than $10^{27}$ ys can be derived from future dijet data, except in the window of relatively light right-handed neutrino masses in the range $0.5$ MeV to $50$ GeV. Part of this mass window will be tested in the upcoming SHiP experiment. We also discuss current and future limits on possible scalar diquark contributions to double beta decay that can be derived from dije...

  14. Lepton nonconservation and double beta decay

    International Nuclear Information System (INIS)

    This paper reviews the status of double beta decay as a test of lepton number conservation. Present limits on the mass of a Majorana neutrino are in the range of 10 to 50 eV. Experiments now in progress should substantially improve these limits

  15. Long term prospects for double beta decay

    OpenAIRE

    Zuber, K.

    2010-01-01

    In rather general terms the long term perspective of double beta decay is discussed. All important experimental parameters are investigated as well as the status of nuclear matrix element issues. The link with other neutrino physics results and options to disentangle the underlying physics process are presented.

  16. Beyond low beta-decay Q values

    Science.gov (United States)

    Mustonen, M. T.; Suhonen, J.

    2010-11-01

    Beta decays with low Q values can be utilized in the quest to determine the neutrino mass scale. This is being realized in two experiments, KATRIN and MARE, using tritium and 187Re, respectively. The beta-decay of 187Re had the lowest known Q value until 2005, when the beta decay of 115In to the first excited state of 115Sn was discovered in Gran Sasso underground laboratory. Last year two independent ion trap measurements confirmed that this decay breaks the former record by an order of magnitude. Our theoretical study on this tiny decay channel complemented the experimental effort by the JYFLTRAP group in Finland and HADES underground laboratory in Belgium. A significant discrepancy between the experimental and theoretical results was found. This might be explained by various atomic contributions known to grow larger as the Q value decreases. However, the traditional recipes for taking these effects into account break down on this new ultra-low Q value regime, providing new challenges for theorists on the borderline between nuclear and atomic physics.

  17. Measurement of the beta asymmetry in neutron beta decay

    International Nuclear Information System (INIS)

    Neutron beta decay is the simplest semi-leptonic weak decay and described accurately by the standard model using the first CKM-matrix element and the ratio of vector and axial vector couplings, λ. With more than a dozen observables it is a sensitive probe for investigating the nature of weak interaction and to search for physics beyond the standard model. In the past, measuring the beta asymmetry A in polarized neutron decay has been the most precise way of determining λ and nowadays it allows - together with other observables - to derive limits on non-standard model interactions, such as scalar and tensor couplings. The neutron decay spectrometer Perkeo III was installed at the PF1B cold neutron beam site at the Institut Laue-Langevin to measure the beta asymmetry. By using a pulsed beam combined with an improved detector design a significant reduction of several systematic uncertainties has been achieved compared to the predecessor, Perkeo II. In this talk recent results of the measurements with Perkeo III will be presented. In particular, we show the energy distribution of the electrons together with the calibration tools for the detectors.

  18. Double beta decay and neutrino mass models

    CERN Document Server

    Helo, J C; Ota, T; Santos, F A Pereira dos

    2015-01-01

    Neutrinoless double beta decay allows to constrain lepton number violating extensions of the standard model. If neutrinos are Majorana particles, the mass mechanism will always contribute to the decay rate, however, it is not a priori guaranteed to be the dominant contribution in all models. Here, we discuss whether the mass mechanism dominates or not from the theory point of view. We classify all possible (scalar-mediated) short-range contributions to the decay rate according to the loop level, at which the corresponding models will generate Majorana neutrino masses, and discuss the expected relative size of the different contributions to the decay rate in each class. We also work out the phenomenology of one concrete 2-loop model in which both, mass mechanism and short-range diagram, might lead to competitive contributions, in some detail.

  19. Isospin mixing and beta decay

    International Nuclear Information System (INIS)

    In this work, we are interested in the breaking of the isospin symmetry in the N ≅ Z nuclei and in its effect on the matrix element of super-allowed 0+ → 0+ Fermi β transitions in the case of the β+ decay of the 50Mn. Within the framework of the Highly Truncated Diagonalization microscopic Approach (HTDA), dedicated to the description of correlations beyond the mean field and conserving explicitly the particle number, we have studied (in particular) the role played by pairing correlations in the breaking mechanisms of this symmetry in the ground state of N ≅ Z nuclei. A sensitivity study of the isospin mixing, as a function of the strength of the residual interaction describing the pairing correlations in HTDA, has been carried out and an interpretation of the mechanisms at work has been proposed in terms of an approximation developed in this work. This study has pointed out the complexity of a good treatment of the isospin symmetry, in the description of the breaking sources as well as in the reduction of model biases. We have also paid attention to the necessity of a very fine description of the correlated wave functions in such a problem. More precisely, we have obtained a value for the isospin mixing correction δC to the Fermi transition matrix element of (0.2 ± 0.1)%. This value has been compared to those obtained in other approaches. Taking account of the neglected effects in our work, our value of δC is expected to be a lower bound. (author)

  20. Exchange effects in double beta decay

    International Nuclear Information System (INIS)

    Over the past decade there has been very impressive progress in the laboratory study of double beta decay with very precise limits on 0-neutrino decay in /sup 76/Ge, the imminent prospect of the observation of 2-neutrino decay in /sup 100/Mo and the first laboratory observation of 2-neutrino decay in /sup 82/Se. For the last case, the laboratory rate is in essential agreement with geochemical results and in reasonable agreement with theoretical predictions based on a full shell model calculation. The motivation underlying the resurgence of interest in double beta decay is the hope that the observation of, or limits on the 0-neutrino mode will provide information about the nature of the neutrino. This clearly requires confidence in the nuclear matrix elements involved in the transition. The shell model calculations do not agree well with the geochemical values for /sup 130/Te, which has led to a spate of papers offering specific fixes for the problem. In this contribution we shall not comment on any of the specific nuclear calculations, rather we make some remarks which should be relevant to any model calculation. 11 refs., 1 tab

  1. Double-beta decay in deformed nuclei

    International Nuclear Information System (INIS)

    A brief review of theoretical results for the double-beta decay and the double-electron capture in heavy deformed nuclei is presented. The ββ half life of 160Gd is evaluated using an extended version of the pseudo SU(3) model. While the 2ν mode is forbidden when the most probable occupations are considered, states with different occupation numbers can be mixed through the pairing interaction. The amount of this mixing is calculated using perturbation theory. The possibility of observing the ββ decay in 160Gd is discussed for both the 2ν and 0ν modes. (author)

  2. JUNO and neutrinoless double beta decay

    Science.gov (United States)

    Ge, Shao-Feng; Rodejohann, Werner

    2015-11-01

    We study the impact of the precision determination of oscillation parameters in the JUNO experiment on half-life predictions for neutrinoless double beta decay. We show that the solar neutrino mixing angle can be measured by JUNO with below 1% uncertainty. This implies in particular that the minimal value of the effective mass in the inverted mass ordering will be known essentially without uncertainty. We demonstrate that this reduces the range of half-life predictions in order to test this value by a factor of 2. The remaining uncertainty is caused by nuclear matrix elements. This has important consequences for future double beta decay experiments that aim at ruling out the inverted mass ordering or the Majorana nature of neutrinos.

  3. JUNO and Neutrinoless Double Beta Decay

    CERN Document Server

    Ge, Shao-Feng

    2015-01-01

    We study the impact of the precision determination of oscillation parameters in the JUNO experiment on half-life predictions for neutrinoless double beta decay. We show that the solar neutrino mixing angle can be measured by JUNO with below 1% uncertainty. This implies in particular that the minimal value of the effective mass in the inverted mass ordering will be known essentially without uncertainty. We demonstrate that this reduces the range of half-life predictions in order to test this value by a factor of two. The remaining uncertainty is caused by nuclear matrix elements. This has important consequences for future double beta decay experiments that aim at ruling out the inverted mass ordering or the Majorana nature of neutrinos.

  4. Importance of neutrinoless double beta decay

    CERN Document Server

    Sarkar, Utpal

    2007-01-01

    A natural explanation for the smallness of the neutrino mass requires them to be Majorana particles violating lepton number by two units. Since lepton number violation can have several interesting consequences in particle physics and cosmology, it is of utmost importance to find out if there is lepton number violation in nature and what is its magnitude. The neutrinoless double beta decay experiment can answer these questions: if there is lepton number violation and if neutrinos are Majorana particles. In addition, the magnitude of neutrinoless double beta decay will constrain any other lepton number violating processes. This lepton number violation may also be relatd to the matter-antimatter asymmetry of the universe, dark matter and cosmological constant.

  5. Search for Neutrinoless Double-Beta Decay

    CERN Document Server

    Tornow, Werner

    2014-01-01

    After the pioneering work of the Heidelberg-Moscow (HDM) and International Germanium Experiment (IGEX) groups, the second round of neutrinoless double-$\\beta$ decay searches currently underway has or will improve the life-time limits of double-$\\beta$ decay candidates by a factor of two to three, reaching in the near future the $T_{1/2} = 3 \\times 10^{25}$ yr level. This talk will focus on the large-scale experiments GERDA, EXO-200, and KamLAND-Zen, which have reported already lower half-life time limits in excess of $10^{25}$ yr. Special emphasis is given to KamLAND-Zen, which is expected to approach the inverted hierarchy regime before future 1-ton experiments probe completely this life-time or effective neutrino-mass regime, which starts at $\\approx 2 \\times 10^{26}$ yr or $\\approx 50$ meV.

  6. Applications of TAGS data in beta decay energies and decay heat calculations

    OpenAIRE

    Pham, N. S.; 片倉 純一

    2007-01-01

    The recent data of beta-decay intensity measured by using the total absorption gamma-ray spectrometer (TAGS), for several fission products (FP), has been applied for calculations of the average energies and spectra, and decay heat summations. The calculations were performed based on the Gross theory of beta decay, in which the beta strength functions were experimentally derived from TAGS data. The deviations of decay heat power predictions from the original decay data of JENDL Decay Data File...

  7. JUNO and Neutrinoless Double Beta Decay

    OpenAIRE

    Ge, Shao-Feng; Rodejohann, Werner

    2015-01-01

    We study the impact of the precision determination of oscillation parameters in the JUNO experiment on half-life predictions for neutrinoless double beta decay. We show that the solar neutrino mixing angle can be measured by JUNO with below 1% uncertainty. This implies in particular that the minimal value of the effective mass in the inverted mass ordering will be known essentially without uncertainty. We demonstrate that this reduces the range of half-life predictions in order to test this v...

  8. NEUTRINOLESS DOUBLE BETA DECAY: AN EXTREME CHALLENGE

    OpenAIRE

    Fernando Ferroni

    2013-01-01

    Neutrino-less Double Beta Decay is the only known way to possibly resolve the nature of neutrino mass. The chances to cover the mass region predicted by the inverted hierarchy require a step forward in detector capability. A possibility is to make use of scintillating bolometers. These devices shall have a great power in distinguishing signals from alfa particles from those induced by electrons. This feature might lead to an almost background-free experiment. Here the Lucifer concept will be ...

  9. Nuclear Data Compilation for Beta Decay Isotope

    Science.gov (United States)

    Olmsted, Susan; Kelley, John; Sheu, Grace

    2015-10-01

    The Triangle Universities Nuclear Laboratory nuclear data group works with the Nuclear Structure and Decay Data network to compile and evaluate data for use in nuclear physics research and applied technologies. Teams of data evaluators search through the literature and examine the experimental values for various nuclear structure parameters. The present activity focused on reviewing all available literature to determine the most accurate half-life values for beta unstable isotopes in the A = 3-20 range. This analysis will eventually be folded into the ENSDF (Evaluated Nuclear Structure Data File). By surveying an accumulated compilation of reference articles, we gathered all of the experimental half-life values for the beta decay nuclides. We then used the Visual Averaging Library, a data evaluation software package, to find half-life values using several different averaging techniques. Ultimately, we found recommended half-life values for most of the mentioned beta decay isotopes, and updated web pages on the TUNL webpage to reflect these evaluations. To summarize, we compiled and evaluated literature reports on experimentally determined half-lives. Our findings have been used to update information given on the TUNL Nuclear Data Evaluation group website. This was an REU project with Triangle Universities Nuclear Laboratory.

  10. Simulation in double-beta decay experiments

    International Nuclear Information System (INIS)

    A detailed understanding of background radiation sources is a key to interpretation and enhanced sensitivity of double-beta decay experiments. Improvement of several techniques will be discussed. An implementation of the EGS4 code was developed to improve the accuracy of detector simulations, in particular for a 100Mo double-beta decay experiment. The efficiency modification due to the angular dependence of the 539 keV - 590 keV gamma-ray coincidence was successfully determined. The success of the 100Mo effort led to the modeling of uranium-thorium backgrounds found in an electroformed copper shield built for a 76Ge experiment. The large copper mass increased our sensitivity to contaminants present in copper produced this way, and led to changes in our cryostat electroforming technique. The original goal was the determination of the 210Pb content of the 450 year old lead shield previously used in 71Ge two-neutrino double-beta decay measurements. The results pertaining to low background materials and fabrication techniques will also be discussed

  11. Weak interaction studies from nuclear beta decay

    International Nuclear Information System (INIS)

    The studies performed at the theoretical nuclear physics division of the Laboratory of Nuclear Studies, Osaka University, are reported. Electron spin density and internal conversion process, nuclear excitation by electron transition, beta decay, weak charged current, and beta-ray angular distributions in oriented nuclei have been studied. The relative intensity of internal conversion electrons for the case in which the radial wave functions of orbital electrons are different for electron spin up and down was calculated. The calculated value was in good agreement with the experimental one. The nuclear excitation following the transition of orbital electrons was studied. The calculated probability of the nuclear excitation of Os189 was 1.4 x 10-7 in conformity with the experimental value 1.7 x 10-7. The second class current and other problems on beta-decay have been extensively studied, and described elsewhere. Concerning weak charged current, the effects of all induced terms, the time component of main axial vector, all partial waves of leptons, Coulomb correction for the electrons in finite size nuclei, and radiative correction were studied. The beta-ray angular distribution for the 1+ -- 0+ transition in oriented B12 and N12 was investigated. In this connection, investigation on the weak magnetism to include all higher order corrections for the evaluation of the spectral shape factors was performed. Other works carried out by the author and his collaborators are also explained. (Kato, T.)

  12. Nuclear responses for neutrinos and neutrino studies by double beta decays and inverse beta decays

    Indian Academy of Sciences (India)

    H Ejiri

    2001-08-01

    This is a brief report on recent studies of nuclear responses for neutrinos () by charge exchange reactions, masses by double beta () decays and of solar and supernova ’s by inverse decays. Subjects discussed include (1) studies in nuclear micro-laboratories, (2) masses studied by decays of 100Mo and nuclear responses for -, (3) solar and supernova ’s by inverse decays and responses for 71Ga and 100Mo, and (4) MOON (molybdenum observatory of neutrinos) for spectroscopic studies of Majorana masses with sensitivity of ∼ 0.03 eV by decays of 100Mo and real-time studies of low energy solar and supernova ’s by inverse decays of 100Mo.

  13. Double beta decay with large scale Yb-loaded scintillators

    OpenAIRE

    Zuber, K.

    2000-01-01

    The potential of large scale Yb-loaded liquid scintillators as proposed for solar neutrino spectroscopy are investigated with respect to double beta decay. The potential for beta-beta- - decay of 176Yb as well as the beta+/EC - decay for 168Yb is discussed. Not only getting for the first time an experimental half-life limit on 176Yb - decay, this will even be at least comparable or better than existing ones from other isotopes. Also for the first time a realistic chance to detect beta+/EC - d...

  14. A background free double beta decay experiment

    CERN Document Server

    Giomataris, Ioannis

    2010-01-01

    We present a new detection scheme for rejecting backgrounds in neutrino less double beta decay experiments. It relies on the detection of Cherenkov light emitted by electrons in the MeV region. The momentum threshold is tuned to reach a good discrimination between background and good events. We consider many detector concepts and a range of target materials. The most promising is a high-pressure 136Xe emitter for which the required energy threshold is easily adjusted. Combination of this concept and a high pressure Time Projection Chamber could provide an optimal solution. A simple and low cost effective solution is to use the Spherical Proportional Counter that provides two delayed signals from ionization and Cherenkov light. In solid-state double beta decay emitters, because of their higher density, the considered process is out of energy range. An alternative solution could be the development of double decay emitters with lower density by using for instance the aerogel technique. It is surprising that a te...

  15. Beta decay of the exotic $T_z$ = -2 nuclei $^{48}$Fe, $^{52}$Ni and $^{56}$Zn

    OpenAIRE

    Orrigo, S. E. A.; Rubio, B.; Fujita, Y; Gelletly, W.; Agramunt, J.; Algora, A.; Ascher, P; Bilgier, B.; Blank, B.; Cáceres, L.; Cakirli, R. B.; Ganioğlu, E.; Gerbaux, M.; Giovinazzo, J.; Grévy, S.

    2016-01-01

    The results of a study of the beta decays of three proton-rich nuclei with $T_z=\\text{-}2$, namely $^{48}$Fe, $^{52}$Ni and $^{56}$Zn, produced in an experiment carried out at GANIL, are reported. In all three cases we have extracted the half-lives and the total $\\beta$-delayed proton emission branching ratios. We have measured the individual $\\beta$-delayed protons and $\\beta$-delayed $\\gamma$ rays and the branching ratios of the corresponding levels. Decay schemes have been determined for t...

  16. Theoretical analysis of the possible ultra-low-Q-value decay branch of {sup 135}Cs

    Energy Technology Data Exchange (ETDEWEB)

    Mustonen, M.T., E-mail: mika.t.mustonen@jyu.fi [Department of Physics, University of Jyvaeskylae, P.O. Box 35 (YFL), FI-40014 Jyvaeskylae (Finland); Suhonen, J., E-mail: jouni.suhonen@phys.jyu.fi [Department of Physics, University of Jyvaeskylae, P.O. Box 35 (YFL), FI-40014 Jyvaeskylae (Finland)

    2011-09-14

    We have investigated the feasibility of observing an ultra-low-Q-value beta-decay branch of {sup 135}Cs by applying the microscopic quasiparticle-phonon model with a realistic two-body nuclear interaction. This work was motivated by an earlier combined experimental and theoretical work on decays of {sup 115}In. The inaccuracy of the ground-state-to-ground-state Q value limits our ability to draw definite conclusions, and therefore modern precision measurements for it are called for. We present the computed partial half-lives of each channel for the most likely ranges of Q values.

  17. Neutrinoless double beta decay search with SNO+

    OpenAIRE

    Lozza V.

    2014-01-01

    The SNO+ experiment is the follow up of SNO. The detector is located 2 km underground in the Vale Canada Ltd.’s Creighton Mine near Sudbury, Ontario, Canada. The active volume of the detector consists of 780 tonnes of Linear Alkyl Benzene (LAB) in an acrylic vessel of 12 m diameter, surrounded by about 9500 PMTs. The main goal of the SNO+ experiment is the search for neutrinoless double beta decay of 130Te. With an initial loading of 0.3% of natural tellurium (nearly 800 kg of 130Te), it is e...

  18. NEUTRINOLESS DOUBLE BETA DECAY: AN EXTREME CHALLENGE

    Directory of Open Access Journals (Sweden)

    Fernando Ferroni

    2013-12-01

    Full Text Available Neutrino-less Double Beta Decay is the only known way to possibly resolve the nature of neutrino mass. The chances to cover the mass region predicted by the inverted hierarchy require a step forward in detector capability. A possibility is to make use of scintillating bolometers. These devices shall have a great power in distinguishing signals from alfa particles from those induced by electrons. This feature might lead to an almost background-free experiment. Here the Lucifer concept will be introduced and the prospects related to this project will be discussed.

  19. Decay parameter and related properties of 2-type branching processes

    Institute of Scientific and Technical Information of China (English)

    LI JunPing

    2009-01-01

    We consider the decay parameter, invariant measures/vectors and quasi-stationary dis-tributions for 2-type Markov branching processes. Investigating such properties is crucial in realizing life period of branching models. In this paper, some important properties of the generating functions for 2-type Markov branching q-matrix are firstly investigated in detail. The exact value of the decay parameter λC of such model is given for the communicating class C = Z+2\\ 0. It is shown that this λC can be directly obtained from the generating functions of the corresponding q-matrix. Moreover, the λC-invariant measures/vectors and quasi-distributions of such processes are deeply considered. A λC-invariant vector for the q-matrix (or for the process) on C is given and the generating functions of λC-invariant measures and quasi-stationary distributions for the process on C are presented.

  20. Decay parameter and related properties of 2-type branching processes

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    We consider the decay parameter, invariant measures/vectors and quasi-stationary dis- tributions for 2-type Markov branching processes. Investigating such properties is crucial in realizing life period of branching models. In this paper, some important properties of the generating functions for 2-type Markov branching q-matrix are firstly investigated in detail. The exact value of the decay parameter λC of such model is given for the communicating class C = Z+2 \\ 0. It is shown that this λC can be directly obtained from the generating functions of the corresponding q-matrix. Moreover, the λC-invariant measures/vectors and quasi-distributions of such processes are deeply considered. A λC-invariant vector for the q-matrix (or for the process) on C is given and the generating functions of λC-invariant measures and quasi-stationary distributions for the process on C are presented.

  1. Isospin and quarks in nuclear beta-decay

    International Nuclear Information System (INIS)

    This paper exposes in some detail the technical problems relating to the extraction of the vector coupling constant from the beta decay of complex nuclei. It also considers the extraction of the axial coupling constant from the beta-decay of the neutron. The internal consistency of all data relating to beta-decay, including that of the muon, is also examined, within the standard model, with a view to the possible intervention of WR. (Author) 52 refs., 4 figs., 2 tabs

  2. Beta-delayed gamma decay of 26P: Possible evidence of a proton halo

    CERN Document Server

    Pérez-Loureiro, D; Bennett, M B; Liddick, S N; Bowe, A; Brown, B A; Chen, A A; Chipps, K A; Cooper, N; Irvine, D; McNeice, E; Montes, F; Naqvi, F; Ortez, R; Pain, S D; Pereira, J; Prokop, C J; Quaglia, J; Quinn, S J; Sakstrup, J; Santia, M; Schwartz, S B; Shanab, S; Simon, A; Spyrou, A; Thiagalingam, E

    2016-01-01

    Background: Measurements of $\\beta$ decay provide important nuclear structure information that can be used to probe isospin asymmetries and inform nuclear astrophysics studies. Purpose: To measure the $\\beta$-delayed $\\gamma$ decay of $^{26}$P and compare the results with previous experimental results and shell-model calculations. Method: A $^{26}$P fast beam produced using nuclear fragmentation was implanted into a planar germanium detector. Its $\\beta$-delayed $\\gamma$-ray emission was measured with an array of 16 high-purity germanium detectors. Positrons emitted in the decay were detected in coincidence to reduce the background. Results: The absolute intensities of $^{26}$P $\\beta$-delayed $\\gamma$-rays were determined. A total of six new $\\beta$-decay branches and 15 new $\\gamma$-ray lines have been observed for the first time in $^{26}$P $\\beta$-decay. A complete $\\beta$-decay scheme was built for the allowed transitions to bound excited states of $^{26}$Si. $ft$ values and Gamow-Teller strengths were a...

  3. Neutrinoless double beta decay search with SNO+

    Science.gov (United States)

    Lozza, V.

    2014-01-01

    The SNO+ experiment is the follow up of SNO. The detector is located 2 km underground in the Vale Canada Ltd.'s Creighton Mine near Sudbury, Ontario, Canada. The active volume of the detector consists of 780 tonnes of Linear Alkyl Benzene (LAB) in an acrylic vessel of 12 m diameter, surrounded by about 9500 PMTs. The main goal of the SNO+ experiment is the search for neutrinoless double beta decay of 130Te. With an initial loading of 0.3% of natural tellurium (nearly 800 kg of 130Te), it is expected to reach a sensitivity on the effective Majorana neutrino mass of about 100 meV after several years of data taking. Designed as a general purpose neutrino experiment, other exciting physical goals can be explored, like the measurement of reactor neutrino oscillations and geo-neutrinos in a geologically-interesting location, watch of supernova neutrinos and studies of solar neutrinos. A first commissioning phase with water filled detector will start at the end of 2013, while the double beta decay phase will start in 2015.

  4. Semiconductor detectors and double beta decay

    International Nuclear Information System (INIS)

    Theoretical physicists have devoted great effort to developing an adequate theory for linking the weak, electromagnetic, and strong forces of nature. Recent theoretical studies and observations of the stability of galaxies have strongly indicated the presence of large amounts of invisible mass. One element in the uncertainty associated with missing mass is the question of whether the neutrino has rest mass. A better understanding of the neutrino, explored in this paper by the possibility of double beta decay in the germanium 76 isotope, could perhaps provide some answers. Nuclear transitions are only energetically possible where the final nucleus is more tightly bound than its parent. The decay of germanium 76 to arsenic 76 is not energetically possible because the arsenic isotope is about 0.9 MeV less tightly bound than the germanium. The selenium 76 isotope, on the other hand, is about 2 MeV more tightly bound; therefore, a transition involving emission of two electrons by a germanium 76 nucleus to form a selenium 76 nucleus is energetically possible. The total energy release in kinetic energy of the beta particles and corresponding neutrinos from the excited daughter product is determined by the energy difference. This energetically possible event, if observed, will provide a breakthrough in understanding the universe. This paper discusses the underlying theory and a germanium detector experiment which could make such a contribution to the resolution of this question

  5. The NEXT double beta decay experiment

    Science.gov (United States)

    Laing, A.; NEXT Collaboration

    2016-05-01

    NEXT (Neutrino Experiment with a Xenon TPC) is a neutrinoless double-beta (ββ0v) decay experiment at Laboratorio Subterraneo de Canfranc (LSC). It is an electroluminescent Time Projection Chamber filled with high pressure 136Xe gas with separated function capabilities for calorimetry and tracking. Energy resolution and background suppression are the two key features of any neutrinoless double beta decay experiment. NEXT has both good energy resolution (handle for background identification provided by track reconstruction. We expect a background rate of 4 × 10-4 counts keV-1 kg-1 yr-1, and a sensitivity to the Majorana neutrino mass of between 80-160 meV (depending on NME) after a run of 3 effective years of the 100 kg scale NEXT-100 detector. The initial phase of NEXT-100, called NEW, is currently being commissioned at LSC. It will validate the NEXT background rate expectations and will make first measurements of the two neutrino ββ2v mode of 136Xe. Furthermore, the NEXT technique can be extrapolated to the tonne scale, thus allowing the full exploration of the inverted hierarchy of neutrino masses. These proceedings review NEXT R&D results, the status of detector commissioning at LSC and the NEXT physics case.

  6. Neutrinoless double beta decay search with SNO+

    Directory of Open Access Journals (Sweden)

    Lozza V.

    2014-01-01

    Full Text Available The SNO+ experiment is the follow up of SNO. The detector is located 2 km underground in the Vale Canada Ltd.’s Creighton Mine near Sudbury, Ontario, Canada. The active volume of the detector consists of 780 tonnes of Linear Alkyl Benzene (LAB in an acrylic vessel of 12 m diameter, surrounded by about 9500 PMTs. The main goal of the SNO+ experiment is the search for neutrinoless double beta decay of 130Te. With an initial loading of 0.3% of natural tellurium (nearly 800 kg of 130Te, it is expected to reach a sensitivity on the effective Majorana neutrino mass of about 100 meV after several years of data taking. Designed as a general purpose neutrino experiment, other exciting physical goals can be explored, like the measurement of reactor neutrino oscillations and geo-neutrinos in a geologically-interesting location, watch of supernova neutrinos and studies of solar neutrinos. A first commissioning phase with water filled detector will start at the end of 2013, while the double beta decay phase will start in 2015.

  7. Beta decay properties from a statistical model

    International Nuclear Information System (INIS)

    The present work assumes that any intrinsic structure in the nuclei involved is not important. Only spin, parity, and energy are considered. Quantities such as half-life, average beta energy, or average gamma energy can be obtained by integrals over the beta strength function weighted by kinematic and other factors. The beta strength function is proportional to the level density multiplied by a reduced transition probability. Delayed neutron emission is calculated by assuming that the daughter is a compound nucleus which then statistically decays as in the Hauser-Feshbach approach. Using the ENDF/B-V fission product file which contains 877 nuclei, energy-dependent reduced transition probabilities were found for allowed 0+ → 1+ transitions (50 cases) and for other allowed transitions (over 600 cases), corresponding to log ft values of 4.3 and 5.6 respectively. No dependence on either transition energy or on mass was found. A reduced transition probability corresponding to log ft of 7.1 was used for first forbidden transitions. Some results are presented and discussed

  8. Neutrinoless double beta decay in Gerda

    Science.gov (United States)

    Grabmayr, Peter; Gerda Collaboration

    2015-10-01

    The Germanium Detector Array (Gerda) experiment searches for the neutrinoless double beta decay in 76Ge. This lepton number violating process is predicted by extensions of the standard model. Gerda follows a staged approach by increasing mass and lowering the background level from phase to phase. Gerda is setup at the Gran Sasso underground laboratory of INFN, Italy. An array of high-purity germanium detectors is lowered directly in liquid argon for shielding and cooling. Further background reduction is achieved by an instrumented water buffer. In Phase I an exposure of 21.6 kg yr was collected at a background level of 10-2 cts/(keV kg yr). The lower limit on the half-life of 76Ge > 2 . 1 .1025 yr (90% C.L.) has been published. Further analyses search for decay into excited states or the accompanied Majoron decay. Presently, Phase II is in preparation which intends to reach a background level of 10-3 cts/(keV kg yr) and to increase the exposure to 100 kg yr. About 20 kg of novel thick-window BEGe (Broad Energy Germanium) detectors will be added and the liquid argon will be instrumented. The status of Phase II preparation and results from the commissioning runs will be presented as well as some further results from Phase I.

  9. COBRA - Double beta decay searches using CdTe detectors

    OpenAIRE

    Zuber, K.

    2001-01-01

    A new approach (called COBRA) for investigating double beta decay using CdTe (CdZnTe) semiconductor detectors is proposed. It follows the idea that source and detector are identical. This will allow simultaneous measurements of 5 $\\beta^-\\beta^-$ - and 4 $\\beta^+\\beta^+$ - emitters at once. Half-life limits for neutrinoless double beta decay of Cd-116 and Te-130 can be improved by more than one order of magnitude with respect to current limits and sensitivities on the effective Majorana neutr...

  10. Study of 193Os beta- decay

    International Nuclear Information System (INIS)

    In this work, the excited levels of 193Ir populated by the beta- decay of 193Os (T1/2 ∼ 30h) were investigated. For that purpose, ∼ 5 mg samples of 99%-enriched 192Os were irradiated under a thermal neutron flux of ∼ 1012 s-1 and then analysed both using single gamma spectroscopy and a 4-detector multi parametric acquisition facility, which provided data for both a gamma gamma coincidence analysis and a directional angular correlation gamma gamma (θ ) study. From these data, 28 transitions were added to this decay scheme, 11 of which were previously known from nuclear reactions and 17 observed for the first time. Eight excited levels were also added to the decay scheme, 3 of which were known from nuclear reaction studies - the remaining 5 are suggested for the first time. Moreover, it was possible to confirm suspicions found in reference that the levels at 848.93 keV and 849.093 keV are indeed the same; it was also possible to confirm the existence of an excited level at 806.9 keV, which had been inferred, but not experimentally confirmed in beta decay studies to date. The angular correlation analysis allowed for the definition of the spin of the excited level at 874 keV as 5/2+; moreover, the results showed a 79% probability that the spin of the 1078 keV level is 5/2/'-, and also restricted the spin possibilities for the new excited level at 960 keV to two values (1/2 or 3/2). It was also possible to measure the multipolarity mixing ratio (δLn+1/Ln) for 43 transitions - 19 of them for the first time and most of the others with a better precision than previously known. Finally, an attempt was made to understand the low-lying levels structure for this nucleus using a theoretical model, which reproduced the ground state and the two lowest-lying excited levels in 193Ir. (author)

  11. Neutrinoless Double Beta Decay: 2015 Review

    Directory of Open Access Journals (Sweden)

    Stefano Dell’Oro

    2016-01-01

    Full Text Available The discovery of neutrino masses through the observation of oscillations boosted the importance of neutrinoless double beta decay (0νββ. In this paper, we review the main features of this process, underlining its key role from both the experimental and theoretical point of view. In particular, we contextualize the 0νββ in the panorama of lepton number violating processes, also assessing some possible particle physics mechanisms mediating the process. Since the 0νββ existence is correlated with neutrino masses, we also review the state of the art of the theoretical understanding of neutrino masses. In the final part, the status of current 0νββ experiments is presented and the prospects for the future hunt for 0νββ are discussed. Also, experimental data coming from cosmological surveys are considered and their impact on 0νββ expectations is examined.

  12. A massive neutrino in nuclear beta decay?

    International Nuclear Information System (INIS)

    We have continued our studies of the p-spectrum of 14C using a germanium detector doped with 14C. There is a feature in the β-spectrum 17 keV below the endpoint which could be explained by the hypothesis that there is a heavy neutrino emitted in the β-decay of 14C with a mass of 17±1 keV and an emission probability of 1.26±0.25%. However, we also have performed a high statistics measurement of the inner bremsstrahlung spectrum of 55Fe and find no indication of the emission of a 17-keV neutrino. We conclude that the origin of the ''kink'' that has been observed in some recent beta spectral measurements is not a neutrino

  13. Neutrinoless Double Beta Decay with SNO+

    CERN Document Server

    Hartnell, J

    2012-01-01

    SNO+ will search for neutrinoless double beta decay by loading 780 tonnes of linear alkylbenzene liquid scintillator with O(tonne) of neodymium. Using natural Nd at 0.1% loading will provide 43.7 kg of 150Nd given its 5.6% abundance and allow the experiment to reach a sensitivity to the effective neutrino mass of 100-200 meV at 90% C.L in a 3 year run. The SNO+ detector has ultra low backgrounds with 7000 tonnes of water shielding and self-shielding of the scintillator. Distillation and several other purification techniques will be used with the aim of achieving Borexino levels of backgrounds. The experiment is fully funded and data taking with light-water will commence in 2012 with scintillator data following in 2013.

  14. A massive neutrino in nuclear beta decay?

    International Nuclear Information System (INIS)

    We have continued our studies of the β-spectrum of 14C using a germanium detector doped with l4C. There is a feature in the β-spectrum 17 keV below the endpoint which could be explained by the hypothesis that there is a heavy neutrino emitted in the β-decay of 14C with a mass of 17±1 keV and an emission probability of 1.26±0.25%. However, we also have performed a high statistics measurement of the inner bremsstrahlung spectrum of 55Fe and find no indication of the emission of a 17-keV neutrino. We conclude that the origin of the ''kink'' that has been observed in some recent beta spectral measurements is not a neutrino

  15. A massive neutrino in nuclear beta decay?

    International Nuclear Information System (INIS)

    We have continued our studies of the β-spectrum of 14C using a germanium detector doped with 14C. There is a feature in the β-spectrum 17 keV below the endpoint which could be explained by the hypothesis that there is a heavy neutrino emitted in the β-decay of 14C with a mass of 17±1 keV and an emission probability of 1.26±0.25%. However, we also have performed a high statistics measurement of the inner bremsstrahlung spectrum of 55Fe and find no indication of the emission of a 17-keV neutrino. We conclude that the origin of the ''kink'' that has been observed in some recent beta spectral measurements is not a neutrino

  16. Branching Fraction Measurements of B ->etac K Decays

    CERN Document Server

    Aubert, Bernard; Boutigny, D; Couderc, F; Gaillard, J M; Hicheur, A; Karyotakis, Yu; Lees, J P; Tisserand, V; Zghiche, A; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Le Clerc, C; Levi, M E; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, Michael T; Shelkov, V G; Telnov, A V; Wenzel, W A; Ford, K; Harrison, T J; Hawkes, C M; Morgan, S E; Watson, A T; Watson, N K; Fritsch, M; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Steinke, M; Boyd, J T; Chevalier, N; Cottingham, W N; Kelly, M P; Latham, T E; Wilson, F F; Abe, K; Çuhadar-Dönszelmann, T; Hearty, C; Mattison, T S; McKenna, J A; Thiessen, D; Kyberd, P; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bruinsma, M; Chao, M; Eschrich, I; Kirkby, D; Lankford, A J; Mandelkern, M A; Mommsen, R K; Röthel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Gary, J W; Shen, B C; Wang, K; Del Re, D; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Dahmes, B; Levy, S L; Long, O; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Eisner, A M; Heusch, C A; Lockman, W S; Schalk, T; Schmitz, R E; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S M; Mancinelli, G; Meadows, B T; Sokoloff, M D; Abe, T; Blanc, F; Bloom, P; Chen, S; Clark, P J; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Smith, J G; Van Hoek, W C; Zhang, L; Harton, J L; Hu, T; Soffer, A; Toki, W H; Wilson, R J; Altenburg, D; Brandt, T; Brose, J; Colberg, T; Dickopp, M; Feltresi, E; Hauke, A; Lacker, H M; Maly, E; Müller-Pfefferkorn, R; Nogowski, R; Otto, S; Schubert, J; Schubert, Klaus R; Schwierz, R; Spaan, B; Bernard, D; Bonneaud, G R; Brochard, F; Grenier, P; Thiebaux, C; Vasileiadis, G; Verderi, M; Bard, D J; Khan, A; Lavin, D; Muheim, F; Playfer, S; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Sarti, A; Treadwell, E; Baldini-Ferroli, R; Calcaterra, A; De Sangro, R; Finocchiaro, G; Patteri, P; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Brandenburg, G; Morii, M; Won, E; Dubitzky, R S; Langenegger, U; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Gaillard, J R; Morton, G W; Nash, J A; Taylor, G P; Grenier, G J; Lee, S J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Prell, S; Rosenberg, E I; Yi, J; Davier, M; Grosdidier, G; Höcker, A; Laplace, S; Le Diberder, F R; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Tantot, L; Wormser, G; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Coleman, J P; Fry, J R; Gabathuler, Erwin; Gamet, R; Kay, M; Parry, R J; Payne, D J; Sloane, R J; Touramanis, C; Back, J J; Harrison, P F; Mohanty, G B; Brown, C L; Cowan, G; Flack, R L; Flächer, H U; George, S; Green, M G; Kurup, A; Marker, C E; McMahon, T R; Ricciardi, S; Salvatore, F; Vaitsas, G; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Hart, P A; Hodgkinson, M C; Lafferty, G D; Lyon, A J; Williams, J C; Farbin, A; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Saremi, S; Stängle, H; Willocq, S; Cowan, R; Sciolla, G; Taylor, F; Yamamoto, R K; Mangeol, D J J; Patel, P M; Robertson, S H; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L M; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Taras, P; Nicholson, H; Cartaro, C; Cavallo, N; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Raven, G; Wilden, L; Jessop, C P; LoSecco, J M; Gabriel, T A; Allmendinger, T; Brau, B; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pulliam, T; Ter-Antonian, R; Wong, Q K; Brau, J E; Frey, R; Igonkina, O; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Tiozzo, G; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; La Vaissière, C de; Del Buono, L; Hamon, O; John, M J J; Leruste, P; Ocariz, J; Pivk, M; Roos, L; T'Jampens, S; Therin, G; Manfredi, P F; Re, V; Behera, P K; Gladney, L; Guo, Q H; Panetta, J; Anulli, F; Biasini, M; Peruzzi, I M; Pioppi, M; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Bucci, F; Calderini, G; Carpinelli, M; Del Gamba, V; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Martínez-Vidal, F; Morganti, M; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Sandrelli, F; Walsh, J; Haire, M; Judd, D; Paick, K; Wagoner, D E; Danielson, N; Elmer, P; Lü, C; Miftakov, V; Olsen, J; Smith, A J S; Varnes, E W; Bellini, F; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Li Gioi, L; Mazzoni, M A; Morganti, S; Pierini, M; Piredda, G; Safai-Tehrani, F; Voena, C; Christ, S; Wagner, G; Waldi, R; Adye, T; De Groot, N; Franek, B J; Geddes, N I; Gopal, G P; Olaiya, E O; Xella, S M; Aleksan, Roy; Emery, S; Gaidot, A; Ganzhur, S F; Giraud, P F; Hamel de Monchenault, G; Kozanecki, Witold; Langer, M; Legendre, M; London, G W; Mayer, B; Schott, G; Vasseur, G; Yéche, C; Zito, M; Purohit, M V; Weidemann, A W; Yumiceva, F X; Aston, D; Bartoldus, R; Berger, N; Boyarski, A M; Buchmüller, O L; Convery, M R; Cristinziani, M; De Nardo, Gallieno; Dong, D; Dorfan, J; Dujmic, D; Dunwoodie, W M; Elsen, E E; Field, R C; Glanzman, T; Gowdy, S J; Hadig, T; Halyo, V; Hast, C; Hrynóva, T; Innes, W R; Kelsey, M H; Kim, P; Kocian, M L; Leith, D W G S; Libby, J; Luitz, S; Lüth, V; Lynch, H L; Marsiske, H; Messner, R; Müller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Petrak, S; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Simi, G; Snyder, A; Soha, A; Stelzer, J; Su, D; Sullivan, M K; Vavra, J; Wagner, S R; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wittgen, M; Wright, D H; Young, C C; Burchat, Patricia R; Edwards, A J; Meyer, T I; Petersen, B A; Roat, C; Ahmed, S; Alam, M S; Ernst, J A; Saeed, M A; Saleem, M; Wappler, F R; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Kim, H; Ritchie, J L; Satpathy, A; Schwitters, R F; Izen, J M; Kitayama, I; Lou, X C; Ye, S; Bianchi, F; Bóna, M; Gallo, F; Gamba, D; Borean, C; Bosisio, L; Cossutti, F; Della Ricca, G; Dittongo, S; Grancagnolo, S; Lanceri, L; Poropat, P; Vitale, L; Vuagnin, G; Panvini, R S; Banerjee, Sw; Brown, C M; Fortin, D; Jackson, P D; Kowalewski, R V; Roney, J M; Band, H R; Dasu, S; Datta, M; Eichenbaum, A M; Hollar, J J; Johnson, J R; Kutter, P E; Li, H; Liu, R; Di Lodovico, F; Mihályi, A; Mohapatra, A K; Pan, Y; Prepost, R; Sekula, S J; Tan, P; Von Wimmersperg-Töller, J H; Wu, J; Wu Sau Lan; Yu, Z; Neal, H

    2004-01-01

    We study the decays B+ -> etac K+ and B0 -> etac K0, where the etac is reconstructed in the Ks K+ pi- and K+ K- pi0 decay modes. Results are based on a sample of 86 million BBbar pairs collected with the BaBar detector at the SLAC e+e- B Factory. We measure the branching fractions BR(B+ -> etac K+) = (1.34 +/- 0.09 +/- 0.13 +/- 0.41) x 10^{-3} and BR(B0 -> etac K0) = (1.18 +/- 0.16 +/- 0.13 +/- 0.37) x 10^{-3}, where the first error is statistical, the second is systematic, and the third reflects the etac branching fraction uncertainty. In addition, we search for B -> etac K events with etac -> 2(K+K-) and etac -> phi phi and determine the etac decay branching fraction ratios BR(etac -> 2(K+K-))/BR(etac -> K Kbar pi) = (2.3 +/- 0.7 +/- 0.6) x 10^{-2} and BR(etac -> phi phi)/BR(etac -> K Kbar pi) = (5.5 +/- 1.4 +/- 0.5) x 10^{-2}.

  17. Double beta decay of 128Te and RIS

    International Nuclear Information System (INIS)

    The paper considers the use of Resonance Ionization Spectroscopy (RIS) in the determination of the electron neutrino mass via the double beta decay of 128Te. An outline is given of the theoretical background to the electron neutrino restmass, and the importance of the neutrino properties in Grand Unification Theories. The detection method for double beta decay is described; the discussion is restricted to tellurium ores and the decays 128Te → 128Xe, and 130Te → 130Xe. A consideration of existing data on double beta decay of 128Te indicates that most aspects of the detection could benefit from RIS. (U.K.)

  18. Scalar-mediated double beta decay and LHC

    CERN Document Server

    Gonzales, L; Hirsch, M; Kovalenko, S G

    2016-01-01

    The decay rate of neutrinoless double beta decay could be dominated by short-range diagrams involving heavy scalar particles ("topology-II" diagrams). Examples are diagrams with diquarks, leptoquarks or charged scalars. Here, we compare the discovery potential for lepton number violating signals at the LHC with constraints from dijet and leptoquark searches and the sensitivity of double beta decay experiments, using three example models. We note that already with 20/fb the LHC will test interesting parts of the parameter space of these models, not excluded by current limits on double beta decay.

  19. Tests of Lorentz Symmetry in Single Beta Decay

    International Nuclear Information System (INIS)

    Low-energy experiments studying single beta decay can serve as sensitive probes of Lorentz invariance that can complement interferometric searches for deviations from this spacetime symmetry. Experimental signatures of a dimension-three operator for Lorentz violation which are unobservable in neutrino oscillations are described for the decay of polarized and unpolarized neutrons as well as for measurements of the spectral endpoint in beta decay

  20. Neutrinoless double beta decay and lepton number violating new physics

    International Nuclear Information System (INIS)

    Neutrinoless double beta decay is a very promising experimental test for lepton number violation. The exchange of light Majorana neutrinos is the simplest realization of this decay, but other physics beyond the Standard Model may also mediate neutrinoless double beta decay. We discuss the interplay of different mechanisms and the influence such an interplay has on the extraction of parameters of the neutrino sector from experimental results.

  1. NEMO 3 double beta decay experiment: latest results

    CERN Document Server

    Barabash, A S

    2008-01-01

    The double beta decay experiment NEMO~3 has been taking data since February 2003. The aim of this experiment is to search for neutrinoless decay and investigate two neutrino double beta decay in seven different enriched isotopes ($^{100}$Mo,$^{82}$Se, $^{48}$Ca, $^{96}$Zr, $^{116}$Cd, $^{130}$Te and $^{150}$Nd). After analysis of the data corresponding to 693 days, no evidence for $0\

  2. Tests of the standard electroweak model in beta decay

    International Nuclear Information System (INIS)

    We review the current status of precision measurements in allowed nuclear beta decay, including neutron decay, with emphasis on their potential to look for new physics beyond the standard electroweak model. The experimental results are interpreted in the framework of phenomenological model-independent descriptions of nuclear beta decay as well as in some specific extensions of the standard model. The values of the standard couplings and the constraints on the exotic couplings of the general beta decay Hamiltonian are updated. For the ratio between the axial and the vector couplings we obtain CA,/CV = -1.26992(69) under the standard model assumptions. Particular attention is devoted to the discussion of the sensitivity and complementarity of different precision experiments in direct beta decay. The prospects and the impact of recent developments of precision tools and of high intensity low energy beams are also addressed. (author)

  3. Tests of the standard electroweak model in beta decay

    Energy Technology Data Exchange (ETDEWEB)

    Severijns, N.; Beck, M. [Universite Catholique de Louvain (UCL), Louvain-la-Neuve (Belgium); Naviliat-Cuncic, O. [Caen Univ., CNRS-ENSI, 14 (France). Lab. de Physique Corpusculaire

    2006-05-15

    We review the current status of precision measurements in allowed nuclear beta decay, including neutron decay, with emphasis on their potential to look for new physics beyond the standard electroweak model. The experimental results are interpreted in the framework of phenomenological model-independent descriptions of nuclear beta decay as well as in some specific extensions of the standard model. The values of the standard couplings and the constraints on the exotic couplings of the general beta decay Hamiltonian are updated. For the ratio between the axial and the vector couplings we obtain C{sub A},/C{sub V} = -1.26992(69) under the standard model assumptions. Particular attention is devoted to the discussion of the sensitivity and complementarity of different precision experiments in direct beta decay. The prospects and the impact of recent developments of precision tools and of high intensity low energy beams are also addressed. (author)

  4. New particle searches by double beta decay

    International Nuclear Information System (INIS)

    So far, neutrinoless double beta decay has not been observed, but the lifetime limit (3-10/sup 23/ years) is such a stringent one that its non-observation can set the best upper limit for the mass of the electron neutrino (if it is a Majorana particle) and the best lower limit on the mass of a heavy Majorana neutrino for a given coupling to the electron neutrino, ν/sub e/. In addition it provides the best limit on the coupling of light bosons, such as Majorons, to ν/sub e/, and also the best limit on the existence of right-handed currents in the case in which all right-handed Majorana neutrinos are heavier than all left-handed leptons. The apparatus has to have such low backgrounds even in the keV energy region that it also can be used to set the best terrestrial limits on the mass of solar axions and of other dark matter candidates

  5. T violation in radiative $\\beta$ decay and electric dipole moments

    CERN Document Server

    Dekens, W G

    2015-01-01

    In radiative $\\beta$ decay, $T$ violation can be studied through a spin-independent $T$-odd correlation. We consider contributions to this correlation by beyond the standard model (BSM) sources of $T$-violation, arising above the electroweak scale. At the same time such sources, parametrized by dimension-6 operators, can induce electric dipole moments (EDMs). As a consequence, the manifestations of the $T$-odd BSM physics in radiative $\\beta$ decay and EDMs are not independent. Here we exploit this connection to show that current EDM bounds already strongly constrain the spin-independent $T$-odd correlation in radiative $\\beta$ decay.

  6. Measurement of the Partial Branching Fraction for Inclusive Charmless Semileptonic B Decays and Extraction of |Vub|

    Energy Technology Data Exchange (ETDEWEB)

    Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; /Annecy, LAPP; Grauges, E.; /Barcelona, IFAE; Palano, A.; Pappagallo, M.; Pompili, A.; /Bari U. /INFN, Bari; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; /Beijing, Inst. High Energy Phys.; Eigen, G.; Ofte, I.; Stugu, B.

    2005-07-06

    Charmless semileptonic decays, {bar B} {yields} X{sub u}{ell}{bar {nu}}, are studied in a sample of 232 million B{bar B} decays recorded with the BABAR detector, in events where the decay of the second B meson is fully reconstructed. Inclusive charmless decays are selected in kinematic regions where the dominant background from semileptonic B decays to charm is reduced by requirements on the hadronic mass M{sub X} and the momentum transfer q{sup 2}. The partial branching fraction for {bar B} {yields} X{sub u}{ell}{bar {nu}} decays for M{sub X} < 1.7 GeV/c{sup 2} and q{sup 2} > 8 GeV{sup 2}/c{sup 4} is measured to be {Delta}{Beta}({bar b} {yields} X{sub u}{ell}{bar {nu}}) = (0.87 {+-} 0.09{sub stat} {+-} 0.09{sub sys} {+-} 0.01{sub th}) x 10{sup -3}. The CKM matrix element|V{sub ub}| is determined by using theoretical calculations of phase space acceptances. Theoretical uncertainties in this extrapolation are reduced by using the inclusive b {yields} s{gamma} photon spectrum and moments of the b {yields} c{ell}{bar {nu}} lepton energy and hadronic invariant mass.

  7. Empirical formula for two neutrino double beta decay

    International Nuclear Information System (INIS)

    The double beta (2β) decay is a rare nuclear weak process in which two neutrons in the nucleus are converted into two protons, and two electrons and two electron antineutrinos are emitted. The process can be thought as a sum of 2β decays. For the double beta decay to be possible, the final nucleus must have a larger binding energy than the original nucleus. The present work aims to develop an empirical formula for computing two neutrino 2β decay half-lives

  8. Neutrino Mass Ordering in Future Neutrinoless Double Beta Decay Experiments

    CERN Document Server

    Zhang, Jue

    2016-01-01

    Motivated by recent intensive experimental efforts on searching for neutrinoless double beta decays, we present a detailed quantitative analysis on the prospect of resolving neutrino mass ordering in the next generation $^{76}$Ge-type experiments.

  9. Neutrinoless double beta decay, solar neutrinos and mass scales

    OpenAIRE

    Osland, Per; Vigdel, Geir

    2001-01-01

    We obtain bounds for the neutrino masses by combining atmospheric and solar neutrino data with the phenomenology of neutrinoless double beta decay where hypothetical values of || are envisaged from future 0\

  10. NEXT, a HPGXe TPC for neutrinoless double beta decay searches

    CERN Document Server

    Granena, F; Nova, F; Rico, J; Sánchez, F; Nygren, D R; Barata, J A S; Borges, F I G M; Conde, C A N; Dias, T H V T; Fernandes, L M P; Freitas, E D C; Lopes, J A M; Monteiro, C M B; Santos, J M F dos; Santos, F P; Tavora, L M N; Veloso, J F C A; Calvo, E; Gil-Botella, I; Novella, P; Palomares, C; Verdugo, A; Giomataris, Yu; Ferrer-Ribas, E; Hernando-Morata, J A; Martínez, D; Cid, X; Ball, M; Carcel, S; Cervera-Villanueva, Anselmo; Díaz, J; Gil, A; Gómez-Cadenas, J J; Martín-Albo, J; Monrabal, F; Munoz-Vidal, J; Serra, L; Sorel, M; Yahlali, N; Bosch, R Esteve; Lerche, C W; Martinez, J D; Mora, F J; Sebastiá, A; Tarazona, A; Toledo, J F; Lazaro, M; Perez, J L; Ripoll, L; Carmona, J M; Cebrián, S; Dafni, T; Galan, J; Gomez, H; Iguaz, F J; Irastorza, I G; Luzón, G; Morales, J; Rodríguez, A; Ruz, J; Tomas, A; Villar, J A

    2009-01-01

    We propose a novel detection concept for neutrinoless double-beta decay searches. This concept is based on a Time Projection Chamber (TPC) filled with high-pressure gaseous xenon, and with separated-function capabilities for calorimetry and tracking. Thanks to its excellent energy resolution, together with its powerful background rejection provided by the distinct double-beta decay topological signature, the design discussed in this Letter Of Intent promises to be competitive and possibly out-perform existing proposals for next-generation neutrinoless double-beta decay experiments. We discuss the detection principles, design specifications, physics potential and R&D plans to construct a detector with 100 kg fiducial mass in the double-beta decay emitting isotope Xe(136), to be installed in the Canfranc Underground Laboratory.

  11. Double beta decay experiments: beginning of a new era

    CERN Document Server

    Barabash, A S

    2012-01-01

    The review of current experiments on search and studying of double beta decay processes is done. Results of the most sensitive experiments are discussed and values of modern limits on effective Majorana neutrino mass ($) are given. New results on two neutrino double beta decay are presented. The special attention is given to new current experiments with mass of studied isotopes more than 100 kg, EXO--200 and KamLAND--Zen. These experiments open a new era in research of double beta decay. In the second part of the review prospects of search for neutrinoless double beta decay in new experiments with sensitivity to $$ at the level of $\\sim 0.01-0.1$ eV are discussed. Parameters and characteristics of the most perspective projects (CUORE, GERDA, MAJORANA, SuperNEMO, EXO, KamLAND--Zen, SNO+) are given.

  12. Complementarity of Neutrinoless Double Beta Decay and Cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Dodelson, Scott; Lykken, Joseph

    2014-03-20

    Neutrinoless double beta decay experiments constrain one combination of neutrino parameters, while cosmic surveys constrain another. This complementarity opens up an exciting range of possibilities. If neutrinos are Majorana particles, and the neutrino masses follow an inverted hierarchy, then the upcoming sets of both experiments will detect signals. The combined constraints will pin down not only the neutrino masses but also constrain one of the Majorana phases. If the hierarchy is normal, then a beta decay detection with the upcoming generation of experiments is unlikely, but cosmic surveys could constrain the sum of the masses to be relatively heavy, thereby producing a lower bound for the neutrinoless double beta decay rate, and therefore an argument for a next generation beta decay experiment. In this case as well, a combination of the phases will be constrained.

  13. Status and Perspectives of Double Beta Decay Searches

    Science.gov (United States)

    Zuber, K.

    2015-11-01

    Double beta decay is an extremely rare process and requires half-life measurements around 1020 years for the neutrino accompanied and well beyond that for the neutrinoless mode. The current status of the search will be discussed.

  14. New exotics in the double beta decay contributions zoo

    OpenAIRE

    Klapdor-Kleingrothaus, H. V.; Päs, H.; Sarkar, U.

    2000-01-01

    We discuss the potential of neutrinoless double beta decay for testing Lorentz invariance and the weak equivalence principle as well as contributions from dilaton exchange gravity in the neutrino sector. While neutrino oscillation bounds constrain the region of large mixing of the weak and gravitational eigenstates, we obtain new constraints on violations of Lorentz invariance and the equivalence principle from neutrinoless double beta decay, applying even in the case of no mixing. Double bet...

  15. Study of the $\\beta$-decay of $^{20}$Mg

    CERN Multimedia

    Cederkall, J A; Riisager, K; Garcia borge, M J; Madurga flores, M; Jonson, B N G; Fynbo, H O U; Koldste, G T; Giles, T J; Nilsson, T; Perea martinez, A

    We propose to perform a detailed study of the $\\beta$-decay of the dripline nucleus $^{20}$Mg. This will provide important information on resonances in $^{20}$Na relevant for the astrophysical rp-process as well as improved information for detailed comparison with state-of-the-art Shell-Model calculations and for comparison with the mirror $\\beta$-decay of $^{20}$O.

  16. Status of the COBRA double beta decay experiment

    Energy Technology Data Exchange (ETDEWEB)

    Zuber, Kai, E-mail: zuber@physik.tu-dresden.d [Inst. fuer Kern- und Teilchenphysik, Technische Universitaet Dresden, 01069 Dresden (Germany)

    2010-01-01

    The current status of the COBRA experiment is described. Results on the 4-fold forbidden beta decay of {sup 113}Cd and a variety of double beta decay limits of Cd, Zn and Te isotopes are presented based on 18 kg x days of exposure with an array of sixteen CdZnTe semiconductor detectors. A short description on the activities with pixelated detectors for tracking is given.

  17. Status of the COBRA double beta decay experiment

    International Nuclear Information System (INIS)

    The current status of the COBRA experiment is described. Results on the 4-fold forbidden beta decay of 113Cd and a variety of double beta decay limits of Cd, Zn and Te isotopes are presented based on 18 kg x days of exposure with an array of sixteen CdZnTe semiconductor detectors. A short description on the activities with pixelated detectors for tracking is given.

  18. Search for neutrinoless double beta decay with DCBA

    International Nuclear Information System (INIS)

    A project called DCBA (Drift Chamber Beta-ray Analyzer) is in progress at KEK in order to search for the events of neutrinoless double beta decay. For investigating technical problems, a test apparatus called DCBA-T has been constructed. The preliminary results of its engineering run are described together with the simulation studies of backgrounds originating from 214Bi and 208Tl

  19. Background capabilities of pixel detectors for double beta decay measurements

    Energy Technology Data Exchange (ETDEWEB)

    Cermak, Pavel, E-mail: pavel.cermak@utef.cvut.cz [Institute of Experimental and Applied Physics, CTU in Prague, 12800 Prague (Czech Republic); Stekl, Ivan; Bocarov, Viktor; Jose, Joshy M.; Jakubek, Jan; Pospisil, Stanislav [Institute of Experimental and Applied Physics, CTU in Prague, 12800 Prague (Czech Republic); Fiederle, Michael; Fauler, Alex [Freiburger Materialforschungszentrum, Albert-Ludwigs-Universitaet Freiburg, D-79104 Freiburg (Germany); Zuber, Kai [Institut fuer Kern- und Teilchenphysik, Technische Universitaet Dresden, 01069 Dresden (Germany); Loaiza, Pia [Laboratoire Souterrain de Modane, 73500 Modane (France); Shitov, Yuriy [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation)

    2011-05-15

    We discuss the possible use of a progressive detection technique based on pixel detectors for the study of double beta decay ({beta}{beta}) processes. A series of background measurements in various environments (surface laboratory, underground laboratory, with and without Pb shielding) was performed using the TimePix silicon hybrid pixel device. The pixel detector response to the natural background and intrinsic background properties measured by a low-background HPGe detector are presented.

  20. Lepton number violating new physics and neutrinoless double beta decay

    International Nuclear Information System (INIS)

    Neutrinoless double beta decay is a very sensitive experimental probe for lepton number violating (ΔL=2) physics beyond the Standard Model. Whatever the new physics mechanism is that triggers the decay, according to the well known Schechter-Valle (or Black Box) theorem, it will induce a Majorana mass term for neutrinos. Neutrinoless double beta decay is therefore the only known possibility to ascertain in the foreseeable future whether the neutrino is a Dirac or a Majorana particle. We discuss the relation between various lepton number violating operators, Majorana neutrino masses, and future experiments.

  1. Status and prospects of searches for neutrinoless double beta decay

    CERN Document Server

    Schwingenheuer, Bernhard

    2012-01-01

    The simultaneous beta decay of two neutrons in a nucleus without the emission of neutrinos (called neutrinoless double beta decay) is a lepton number violating process which is not allowed in the Standard Model of particle physics. More than a dozen experiments using different candidate isotopes and a variety of detection techniques are searching for this decay. Some (EXO-200, Kamland-Zen, GERDA) started to take data recently. EXO and Kamland-Zen have reported first limits of the half life $T_{1/2}^{0\

  2. Systematic study of double beta decay to excited final states

    International Nuclear Information System (INIS)

    A systematic study of two-neutrino double beta (2νββ) decay to the final ground state and excited states is performed within a microscopic quasiparticle random phase approximation (QRPA) model. The excited states are assumed to have the structure of one or two QRPA phonons. This study of the 2νββ decay rates is complemented with the study of single-beta-decay feeding of the relevant nuclei taking part in the double beta process. The Woods-Saxon single-particle energies have been corrected near the Fermi surface by comparing the BCS quasi-particle energies with spectroscopic data of the relevant odd-mass nuclei. Pairing gaps, energy systematics of the Gamow-Teller-States and the available beta-decay data have been used to obtain effective, model-space adapted, two-body matrix elements starting from the G-matrix elements of the Bonn one-boson-exchange potential. This enables a parameter-free calculation of the double Gamow-Teller matrix elements and theoretical prediction of double-beta half lives. The harmonic two-phonon approximation has been used in the beta-decay analysis and the subsequent 2νββ calculations. (authors)

  3. Unique forbidden beta decays and neutrino mass

    Energy Technology Data Exchange (ETDEWEB)

    Dvornický, Rastislav, E-mail: dvornicky@dnp.fmph.uniba.sk [Dzhelepov Laboratory of Nuclear Problems, JINR 141980 Dubna (Russian Federation); Comenius University, Mlynská dolina F1, SK-842 48 Bratislava (Slovakia); Šimkovic, Fedor [Comenius University, Mlynská dolina F1, SK-842 48 Bratislava (Slovakia); Boboliubov Laboratory of Theoretical Physics, JINR 141980 Dubna (Russian Federation); Czech Technical University in Prague, 128-00 Prague (Czech Republic)

    2015-10-28

    The measurement of the electron energy spectrum in single β decays close to the endpoint provides a direct determination of the neutrino masses. The most sensitive experiments use β decays with low Q value, e.g. KATRIN (tritium) and MARE (rhenium). We present the theoretical spectral shape of electrons emitted in the first, second, and fourth unique forbidden β decays. Our findings show that the Kurie functions for these unique forbidden β transitions are linear in the limit of massless neutrinos like the Kurie function of the allowed β decay of tritium.

  4. tan\\beta\\ determination from the Higgs boson decay at the International Linear Collider

    CERN Document Server

    Yokoya, Hiroshi

    2014-01-01

    We study the methods and their accuracies for determining tan\\beta\\ in two Higgs doublet models at future lepton colliders. In addition to the previously proposed methods using direct production of additional Higgs bosons, we propose a method using the precision measurement of the decay branching ratio of the standard-model (SM)-like Higgs boson. The method is available if there is a deviation from the SM in the coupling constants of the Higgs boson with the weak gauge bosons. We find that, depending on the type of Yukawa interactions, this method can give the best sensitivity in a wide range of tan\\beta.

  5. Status and perspectives of double beta decay searches

    International Nuclear Information System (INIS)

    Double beta decay is a very rare nuclear decay characterised by a change of 2 units the ordering number Z while leaving the mass number A constant. It can basically occur in two modes, with the emission of two electrons and two anti-neutrinos or the emission of two electrons only. The neutrinoless double beta decay of nuclei is not allowed in the Standard Model and is of outstanding importance for neutrino physics. It can only occur if a neutrino is its own antiparticle and if it has a non-vanishing rest mass. After a general introduction into double beta decay, the talk focusses on the current experimental searches and results and their implications for particle physics. An outlook towards future projects and the involved challenges is given. This includes a discussion on nuclear matrix elements and possible supporting experimental activities.

  6. Neutrinoless Double Beta Decay and High-Scale Baryogenesis

    CERN Document Server

    Graf, Lukas; Huang, Wei-Chih

    2015-01-01

    The constraints on baryogenesis models obtained from an observation of neutrinoless double beta decay are discussed. The lepton number violating processes, which can underlie neutrinoless double beta decay, would together with sphaleron processes, which are effective in a wide range of energies, wash out any primordial baryon asymmetry of the universe. Typically, if a mechanism of neutrinoless double beta decay other than the standard light neutrino exchange is observed, typical scenarios of high-scale baryogenesis will be excluded. This can be achieved by different methods, e.g. through the observation in multiple isotopes or the measurement of the decay distribution. In addition, we will also highlight the connection with low energy lepton flavour violation and lepton number violation at the LHC.

  7. Nuclear matrix elements for double-{\\beta} decay

    CERN Document Server

    Barea, J; Iachello, F; 10.1103/PhysRevC.87.014315

    2013-01-01

    Background: Direct determination of the neutrino mass through double-$\\beta$ decay is at the present time one of the most important areas of experimental and theoretical research in nuclear and particle physics. Purpose: We calculate nuclear matrix elements for the extraction of the average neutrino mass in neutrinoless double-$\\beta$ decay. Methods: The microscopic interacting boson model (IBM-2) is used. Results: Nuclear matrix elements in the closure approximation are calculated for $^{48}$Ca, $^{76}$Ge, $^{82}$Se, $^{96}$Zr, $^{100}$Mo, $^{110}$Pd, $^{116}$Cd, $^{124}$Sn, $^{128}$Te, $^{130}$Te, $^{148}$Nd, $^{150}$Nd, $^{154}$Sm, $^{160}$Gd, and $^{198}$Pt decay. Conclusions: Realistic predictions for the expected half-lives in neutrinoless double-$\\beta$ decay with light and heavy neutrino exchange in terms of neutrino masses are made and limits are set from current experiments.

  8. Status and perspectives of double beta decay searches

    Energy Technology Data Exchange (ETDEWEB)

    Zuber, Kai [Inst. fuer Kern- und Teilchenphysik, TU Dresden (Germany)

    2011-07-01

    Double beta decay is a very rare nuclear decay characterised by a change of 2 units the ordering number Z while leaving the mass number A constant. It can basically occur in two modes, with the emission of two electrons and two anti-neutrinos or the emission of two electrons only. The neutrinoless double beta decay of nuclei is not allowed in the Standard Model and is of outstanding importance for neutrino physics. It can only occur if a neutrino is its own antiparticle and if it has a non-vanishing rest mass. After a general introduction into double beta decay, the talk focusses on the current experimental searches and results and their implications for particle physics. An outlook towards future projects and the involved challenges is given. This includes a discussion on nuclear matrix elements and possible supporting experimental activities.

  9. $^{11}$Be($\\beta$p), a quasi-free neutron decay?

    CERN Document Server

    Riisager, K.; Borge, M.J.G.; Briz, J.A.; Carmona-Gallardo, M.; Fraile, L.M.; Fynbo, H.O.U.; Giles, T.; Gottberg, A.; Heinz, A.; Johansen, J.G.; Jonson, B.; Kurcewicz, J.; Lund, M.V.; Nilsson, T.; Nyman, G.; Rapisarda, E.; Steier, P.; Tengblad, O.; Thies, R.; Winkler, S.R.

    2014-01-01

    We have observed $\\beta$-delayed proton emission from the neutron-rich nucleus $^{11}$Be by analysing a sample collected at the ISOLDE facility at CERN with accelerator mass spectrometry (AMS). With a branching ratio of (8.4 $\\pm$ 0.6)$\\times$ 10$^{-6}$ the strength of this decay mode, as measured by the B$_\\mathrm{GT}$-value, is unexpectedly high. The result is discussed within a simple single-particle model and could be interpreted as a quasi-free decay of the $^{11}$Be halo neutron into a single-proton state.

  10. Precision measurement of the half-life and the $\\beta$-decay Q value of the superallowed 0$^{+}\\rightarrow$ 0$^{+}\\beta$-decay of $^{38}$Ca

    CERN Multimedia

    2002-01-01

    We propose to study the $\\beta$-decay of $^{38}$Ca. In a first instance, we intend to perform a high-precision study of the half-life of this nucleus as well as a measurement of its $\\beta$-decay Q-value with ISOLTRAP. At a later stage, we propose to study its decay branches to determine the super-allowed branching ratio with high precision. These measurements are essential to improve our understanding of the theoretical corrections (in particular the $\\delta$c correction factor) needed to calculate the universal Ft value from the ft value determined for individual nuclei. For this nucleus, the correction factor is predicted to increase significantly as compared to the nine well-studied nuclei between $^{10}$C and $^{54}$Co and the model calculations used to determine the corrections, in particular the shell-model calculations, are well under control in this mass region. Therefore, the T$_{Z}$= -1 nuclei between A=18 and A=38 are ideal test cases for the correction factors which limit today the precision on t...

  11. Measurement of the Branching Fraction and Time-Dependent CP Asymmetry in the Decay B0->D*+D*-Ks

    CERN Document Server

    Aubert, B; Boutigny, D; Couderc, F; Karyotakis, Yu; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Graugès-Pous, E; Palano, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Gill, M S; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; Del, P; Amo Sanchez; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Watson, A T; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schröder, T; Steinke, M; Boyd, J T; Burke, J P; Cottingham, W N; Walker, D; Asgeirsson, D J; Çuhadar-Dönszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Kyberd, P; Saleem, M; Sherwood, D J; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Bruinsma, M; Chao, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M A; Mommsen, R K; Röthel, W; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Zhang, L; Hadavand, H K; Hill, E J; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dvoretskii, A; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Ruddick, W O; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Chen, A; Eckhart, E A; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Zeng, Q; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Merkel, J; Petzold, A; Spaan, B; Brandt, T; Klose, V; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Thiebaux, C; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; De Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo, M; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Flack, R L; Nash, J A; Nikolich, M B; Panduro-Vazquez, W; Behera, P K; Chai, X; Charles, M J; Mallik, U; Meyer, N T; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gritsan, A V; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Davier, M; Grosdidier, G; Höcker, A; Le Diberder, F R; Lepeltier, V; Lutz, A M; Oyanguren, A; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Stocchi, A; Wang, W F; Wormser, G; Cheng, C H; Lange, D J; Wright, D M; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; George, K A; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; Di Lodovico, F; Menges, W; Sacco, R; Cowan, G; Flächer, H U; Hopkins, D A; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Wren, A C; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; Naisbit, M T; Williams, J C; Yi, J I; Chen, C; Hulsbergen, W D; Jawahery, A; Lae, C K; Roberts, D A; Simi, G; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Saremi, S; Stängle, H; Cowan, R; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Kim, H; Mclachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; Cavallo, N; De Nardo, Gallieno; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M A; Raven, G; Snoek, H L; Jessop, C P; LoSecco, J M; Allmendinger, T; Benelli, G; Corwin, L A; Gan, K K; Honscheid, K; Hufnagel, D; Jackson, P D; Kagan, H; Kass, R; Rahimi, A M; Regensburger, J J; Ter-Antonian, R; Wong, Q K; Blount, N L; Brau, J E; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; Del, L; Buono; La Vaissière, C de; Hamon, O; Hartfiel, B L; Leruste, P; Malcles, J; Ocariz, J; Roos, L; Therin, G; Gladney, L; Biasini, M; Covarelli, R; Angelini, C; Batignani, G; Bettarini, S; Bucci, F; Calderini, G; Carpinelli, M; Cenci, R; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Mazur, M A; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Haire, M; Judd, D; Wagoner, D E; Biesiada, J; Danielson, N; Elmer, P; Lau, Y P; Lü, C; Olsen, J; Smith, A J S; Telnov, A V; Bellini, F; Cavoto, G; D'Orazio, A; Del Re, D; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Safai-Tehrani, F; Voena, C; Ebert, M; Schröder, H; Waldi, R; Adye, T; De Groot, N; Franek, B; Olaiya, E O; Wilson, F F; Aleksan, R; Emery, S; Gaidot, A; Ganzhur, S F; Hamel de Monchenault, G; Kozanecki, Witold; Legendre, M; Vasseur, G; Yéche, C; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Bechtle, P; Berger, N; Claus, R; Coleman, J P; Convery, M R; Cristinziani, M; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dujmic, D; Dunwoodie, W M; Field, R C; Glanzman, T; Gowdy, S J; Graham, M T; Grenier, P; Halyo, V; Hast, C; Hrynóva, T; Innes, W R; Kelsey, M H; Kim, P; Leith, D W G S; Li, S; Luitz, S; Lüth, V; Lynch, H L; MacFarlane, D B; Marsiske, H; Messner, R; Müller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Pulliam, T; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Stelzer, J; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Vavra, J; Van Bakel, N; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Yi, K; Young, C C; Burchat, P R; Edwards, A J; Majewski, S A; Petersen, B A; Roat, C; Wilden, L; Ahmed, S; Alam, M S; Bula, R; Ernst, J A; Jain, V; Pan, B; Saeed, M A; Wappler, F R; Zain, S B; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Ritchie, J L; Satpathy, A; Schilling, C J; Schwitters, R F; Izen, J M; Lou, X C; Ye, S; Bianchi, F; Gallo, F; Gamba, D; Bomben, M; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Dittongo, S; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martínez-Vidal, F; Banerjee, Sw; Bhuyan, B; Brown, C M; Fortin, D; Hamano, K; Kowalewski, R V; Nugent, I M; Roney, J M; Sobie, R J; Back, J J; Harrison, P F; Latham, T E; Mohanty, G B; Pappagallo, M; Band, H R; Chen, X; Cheng, B; Dasu, S; Datta, M; Flood, K T; Hollar, J J; Kutter, P E; Mellado, B; Mihályi, A; Pan, Y; Pierini, M; Prepost, R; Wu, S L; Yu, Z; Neal, H

    2006-01-01

    We study the decay B0->D*+D*-Ks using (230 +/- 2) x 10^{6} BBbar pairs collected by the Babar detector at the PEP-II B factory. We measure a branching fraction B(B0->D*+D*-Ks)=(4.4\\pm0.4\\pm0.7)\\times 10^{-3} and find evidence for the decay B0->D*- D+_{s1}(2536) with a statistical significance of $4.6 \\sigma$. A time-dependent CP asymmetry analysis is also performed to study the possible resonant contributions to B0->D*+D*-Ks and the sign of cos2beta . Our measurement indicates that there is a sizable resonant contribution to the decay B0->D*+D*-Ks from a unknown $D^+_{s1}$ state with large width, and that cos2beta is positive at the 94 % confidence level under certain theoretical assumptions.

  12. Sizeable beta-strength in 31Ar (beta 3p) decay

    DEFF Research Database (Denmark)

    T. Koldste, G.; Blank, B.; J. G. Borge, M.;

    2014-01-01

    We present for the first time precise spectroscopic information on the recently discovered decay mode beta-delayed 3p-emission. The detection of the 3p events gives an increased sensitivity to the high energy part of the Gamow-Teller strength distribution from the decay of 31Ar revealing that as...... much as 30% of the strength resides in the beta-3p decay mode. A simplified description of how the main decay modes evolve as the excitation energy increases in 31Cl is provided....

  13. Branching ratios and properties of D-meson decays

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, M.P.; Calvino, F.; Crespo, J.M. (Universidad Autonoma de Barcelona (Spain)); Barate, R.; Burmeister, H.; Di Ciaccio, L.; Ferrer, A.; Giomataris, Y.; Pattison, B.; Treille, D.; Zolnierowski, Y. (European Organization for Nuclear Research, Geneva (Switzerland)); Bloch, D.; Engel, J.P.; Foucault, P.; Gerber, J.P.; Strub, R. (Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires); Bonamy, P.; Borgeaud, P.; David, M.; Lemoigne, Y.; Magneville, C.; Primout, M.; Villet, G. (CEA Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France). Dept. de Physique des Particules Elementaires); Burchell, M.; Cattaneo, M.; Dixon, J.; Duane, A.; Forty, R.W.; Seez, C.; Websdale, D.M. (Imperial Coll. of Science and Technology, London (UK). Blackett Lab.); Brunet, J.M.; Lefievre, B.; Poutot, D.; Triscos, P.; Tristram, G.; Volte, A. (College de France, 75 - Paris (France)); Almagne, B. d' ; Druet, P.; Krafft, C.; Roudeau, P.; Six, J.; Wayne, M.; Wormser, G. (Institut National; NA14/2 Collaboration

    1991-04-01

    Properties of D mesons produced in the photoproduction experiment NA14/2 at CERN are reported. The following ratios of branching fractions were measured: Br(D{sup 0}{yields}K{sup +}K{sup -})/Br(D{sup 0}{yields}K{sup -}{pi}{sup +})=0.16{plus minus}0.05, Br(D{sup 0}{yields}K{sup -}{pi}{sup +}{pi}{sup 0})/Br(D{sup 0}{yields}K{sup -}{pi}{sup +})=4.0{plus minus}0.9{plus minus}1.0, Br(D{sup 0}{yields}K{sup -}{pi}{sup +}{pi}{sup +}{pi}{sup -})/Br(D{sup 0}{yields}K{sup -}{pi}{sup +})=1.9{plus minus}0.25{plus minus}0.20. The D{sup 0}{yields}K{sup -}{pi}{sup +}{pi}{sup +}{pi}{sup -} decay was analysed and the contribution of resonant subprocesses found consistent with 1{rho}{sup 0} and 0.23 anti K{sup *0} per event. The angular distributions of D{sup 0}{yields}anti K{sup *0}{rho}{sup 0} showed parity violation and destructive interference between S- and D-waves. From a Dalitz-plot analysis of the decay D{sup +}{yields}K{sup -}{pi}{sup +}{pi}{sup +} the contribution from the quasi two-body decay D{sup +}{yields}anti K{sup *0}{pi}{sup +} was measured to be 0.14{plus minus}0.04{plus minus}0.04. (orig.).

  14. The Enriched Xenon Observatory (EXO) for double beta decay

    International Nuclear Information System (INIS)

    The Enriched Xenon Observatory (EXO) is an experimental program designed to search for the neutrinoless double beta decay (0νββ) of Xe-136. of 0nbb would determine an absolute mass scale for neutrinos and answer the question about their Majorana nature. The current phase of the experiment, EXO-200, uses 200 kg of liquid xenon with 80% enrichment in Xe-136. The double beta decay of xenon is detected in an ultra-low background time projection chamber by collecting both, the scintillation light and the ionization charge. The detector has provided the first measurement of two neutrino double beta decay and continues to take data for a neutrinoless analysis.

  15. Sensitivity of NEXT-100 to neutrinoless double beta decay

    CERN Document Server

    Martín-Albo, J; Ferrario, P.; Nebot-Guinot, M.; Gomez-Cadenas, J.J.; Alvarez, V.; Azevedo, C.D.R.; Borges, F.I.G.; Carcel, S.; Cebrian, S.; Cervera, A.; Conde, C.A.N.; Diaz, J.; Diesburg, M.; Esteve, R.; Fernandes, L.M.P.; Ferreira, A.L.; Freitas, E.D.C.; Gehman, V.M.; Goldschmidt, A.; Gonzalez-Diaz, D.; Gutierrez, R.M.; Hauptman, J.; Henriques, C.A.O.; Hernando Morata, J.A.; Labarga, L.; Laing, A.; Lebrun, P.; Liubarsky, I.; Lopez-March, N.; Lorca, D.; Losada, M.; Mari, A.; Martinez-Lema, G.; Martinez, A.; Miller, T.; Monrabal, F.; Monserrate, M.; Monteiro, C.M.B.; Mora, F.J.; Moutinho, L.M.; Novella, P.; Nygren, D.; Para, A.; Perez, J.; Perez Aparicio, J.L.; Querol, M.; Renner, J.; Ripoll, L.; Rodriguez, J.; Santos, F.P.; dos Santos, J.M.F.; Serra, L.; Shuman, D.; Simon, A.; Sofka, C.; Sorel, M.; Stiegler, T.; Toledo, J.F.; Torrent, J.; Tsamalaidze, Z.; Veloso, J.F.C.A.; Villar, J.A.; Webb, R.; White, J.T.; Yahlali, N.; Yepes-Ramirez, H.

    2016-01-01

    NEXT-100 is an electroluminescent high-pressure xenon gas time projection chamber that will search for the neutrinoless double beta decay of Xe-136. The detector possesses two features of great value in neutrinoless double beta decay searches: very good energy resolution (better than 1% FWHM at the Q value of Xe-136) and track reconstruction for the discrimination of signal and background events. This combination results in excellent sensitivity, as discussed in this paper. Detailed Monte Carlo detector simulations and material-screening measurements predict a background rate for NEXT-100 of at most 0.0004 counts/(keV kg yr). Accordingly, the detector will reach a sensitivity to the neutrinoless double beta decay half-life of 6.E25 years after running for 3 effective years.

  16. Short-range correlations and neutrinoless double beta decay

    CERN Document Server

    Kortelainen, M; Suhonen, J; Toivanen, J

    2007-01-01

    In this work we report on the effects of short-range correlations upon the matrix elements of neutrinoless double beta decay. We focus on the calculation of the matrix elements of the neutrino-mass mode of neutrinoless double beta decays of 48Ca and 76Ge. The nuclear-structure components of the calculation, that is the participant nuclear wave functions, have been calculated in the shell-model scheme for 48Ca and in the proton-neutron quasiparticle random-phase approximation (pnQRPA) scheme for 76Ge. We compare the traditional approach of using the Jastrow correlation function with the more complete scheme of the unitary correlation operator method (UCOM). Our results indicate that the Jastrow method vastly exaggerates the effects of short-range correlations on the neutrinoless double beta decay nuclear matrix elements.

  17. Q value of the 100Mo Double-Beta Decay

    CERN Document Server

    Rahaman, S; Eronen, T; Hakala, J; Jokinen, A; Julin, J; Kankainen, A; Saastamoinen, A; Suhonen, J; Weber, C; Äystö, J

    2007-01-01

    Penning trap measurements using mixed beams of 100Mo - 100Ru and 76Ge - 76Se have been utilized to determine the double-beta decay Q-values of 100Mo and 76Ge with uncertainties less than 200 eV. The value for 76Ge, 2039.04(16) keV is in agreement with the published SMILETRAP value. The new value for 100Mo, 3034.40(17) keV is 30 times more precise than the previous literature value, sufficient for the ongoing neutrinoless double-beta decay searches in 100Mo. Moreover, the precise Q-value is used to calculate the phase-space integrals and the experimental nuclear matrix element of double-beta decay.

  18. A search for double beta decay of 136Xe

    International Nuclear Information System (INIS)

    An experiment on double beta decay of 136Xe has been performed at the Gran Sasso Underground Laboratory (L.N.G.S.). From 6210 h of run with xenon enriched to 64% in 136Xe a 90% C.L. lower limit was derived for neutrinoless double beta decay of 2.0x1022y and 6.5x1021y, for the 0+→0+ and 0+→2+ transitions, respectively. From a comparison between enriched xenon and cleaned xenon a lower limit for the two neutrinos double beta decay of 1.4x1020y at 90% C.L. is also obtained (author) 7 refs., 1 fig., 1 tab

  19. Sensitivity of CUORE to Neutrinoless Double-Beta Decay

    CERN Document Server

    Alessandria, F; Ardito, R; Arnaboldi, C; Avignone, F T; Balata, M; Bandac, I; Banks, T I; Bari, G; Beeman, J; Bellini, F; Bersani, A; Biassoni, M; Bloxham, T; Brofferio, C; Bryant, A; Bucci, C; Cai, X Z; Canonica, L; Capelli, S; Carbone, L; Cardani, L; Carrettoni, M; Casali, N; Chott, N; Clemenza, M; Cosmelli, C; Cremonesi, O; Creswick, R J; Dafinei, I; Dally, A; De Biasi, A; Decowski, M P; Deninno, M M; de Waard, A; Di Domizio, S; Ejzak, L; Faccini, R; Fang, D Q; Farach, H A; Ferri, E; Ferroni, F; Fiorini, E; Foggetta, L; Franceschi, M A; Freedman, S J; Frossati, G; Fujikawa, B; Giachero, A; Gironi, L; Giuliani, A; Goett, J; Gorla, P; Gotti, C; Guardincerri, E; Gutierrez, T D; Haller, E E; Han, K; Heeger, K M; Huang, H Z; Ichimura, K; Kadel, R; Kazkaz, K; Keppel, G; Kogler, L; Kolomensky, Yu G; Kraft, S; Lenz, D; Li, Y L; Liu, X; Longo, E; Ma, Y G; Maiano, C; Maier, G; Maino, M; Mancini, C; Martinez, C; Martinez, M; Maruyama, R H; Moggi, N; Morganti, S; Napolitano, T; Newman, S; Nisi, S; Nones, C; Norman, E B; Nucciotti, A; Orio, F; Orlandi, D; Ouellet, J; Pallavicini, M; Palmieri, V; Pattavina, L; Pavan, M; Pedretti, M; Pessina, G; Pirro, S; Previtali, E; Rampazzo, V; Rimondi, F; Rosenfeld, C; Rusconi, C; Salvioni, C; Sangiorgio, S; Schaeffer, D; Scielzo, N D; Sisti, M; Smith, A R; Stivanello, F; Taffarello, L; Terenziani, G; Tian, W D; Tomei, C; Trentalange, S; Ventura, G; Vignati, M; Wang, B; Wang, H W; Whitten, C A; Wise, T; Woodcraft, A; Xu, N; Zanotti, L; Zarra, C; Zhu, B X; Zucchelli, S

    2011-01-01

    We study the sensitivity of CUORE, a bolometric double-beta decay experiment under construction at the Laboratori Nazionali del Gran Sasso in Italy. Two approaches to the computation of experimental sensitivity are discussed and compared, and the formulas and parameters used in the estimation of the sensitivity are provided. Assuming a background rate of 10^-2 cts/(keV kg y), we find that, after 5 years of live time, CUORE has a 1 sigma sensitivity to the neutrinoless double-beta decay half-life of T_1/2 = 1.6 \\times 10^26 y and thus a potential to probe the effective Majorana neutrino mass down to 41-95 meV. This range is compared with the claim of observation of neutrinoless double-beta decay in 76Ge and the preferred range of the neutrino mass parameter space from oscillation results.

  20. Neutrino Decay and Neutrinoless Double Beta Decay in a 3-3-1 Model

    OpenAIRE

    Dias, Alex G.; Doff, A.(Universidade Tecnológica Federal do Paraná – UTFPR – DAFIS, Av. Monteiro Lobato Km 04, 84016-210 Ponta Grossa, PR, Brazil); Pires, C. A. de S.; da Silva, P. S. Rodrigues

    2005-01-01

    In this work we show that the implementation of spontaneous breaking of the lepton number in the 3-3-1 model with right-handed neutrinos gives rise to fast neutrino decay with majoron emission and generates a bunch of new contributions to the neutrinoless double beta decay.

  1. Search for beta sup - and beta sup -beta sup - decays of sup 4 sup 8 Ca

    CERN Document Server

    Bakalyarov, A; Barabash, A; Briançon, C; Brudanin, V; Egorov, V; Hubert, F; Hubert, P; Kovalik, A; Lebedev, V I; Rukhadze, N I; Stekl, I; Umatov, V; Vylov, T D

    2002-01-01

    A sup 4 sup 8 CaCO sub 3 powder sample containing 20.18 g of sup 4 sup 8 Ca was measured for 797 h with a 400 cm sup 3 low-background HPGe detector. New limits on decays of sup 4 sup 8 Ca were obtained. For single beta transitions to sup 4 sup 8 Sc the limits are equal to 0.71x10 sup 2 sup 0 y, 1.1x10 sup 2 sup 0 y, and 0.82x10 sup 2 sup 0 y for transitions to the ground state, excited 5 sup + and 4 sup + states, respectively. The new limits on double beta decay to excited states of sup 4 sup 8 Ti are equal to 0.47x10 sup 2 sup 0 y, 1.1x10 sup 2 sup 0 y, and 0.90x10 sup 2 sup 0 y for transitions to the first 2 sup + , second 2 sup + and first 0 sup + excited states, respectively. All limits are given at the 90% CL.

  2. Double beta decay of 100Mo

    International Nuclear Information System (INIS)

    Using a liquid argon ionization chamber, the 2νββ decay of 100 Mo was detected with its half-life of (7.5 ± 1.1(stat.) ± 1.5(syst.)) · 1018 y. The limits on half-lives for the 0ν and 0νχ0 decays of 100Mo were estimated as 9.3(5.0) · 1021 and 4.3(2.7) · 1020 y respectively at 68 % (90%) C.L. Available world data for the 2νββ decay of 100Mo lead to the average 'world' value of the half-life, T1/2 = (8.0 ± 0.7) · 1018 y, which corresponds to the nuclear matrix element, MGT = 0.118 ± 0.005

  3. On Gamow-Teller strength distributions for $\\beta\\beta$-decaying nuclei within continuum-QRPA

    CERN Document Server

    Igashov, S Yu; Faessler, Amand; Urin, M H

    2010-01-01

    An isospin-selfconsistent pn-continuum-QRPA approach is formulated and applied to describe the Gamow-Teller strength distributions for $\\beta\\beta$-decaying open-shell nuclei. The calculation results obtained for the pairs of nuclei $^{76}$Ge-Se, $^{100}$Mo-Ru, $^{116}$Cd-Sn, and $^{130}$Te-Xe are compared with available experimental data.

  4. Possible background reductions in double beta decay experiments

    CERN Document Server

    Arnold, R; Baker, J; Barabash, A S; Bing, O; Brudanin, V B; Caffrey, A J; Caurier, E; Errahmane, K; Etienvre, A I; Guyonnet, J L; Hubert, F; Hubert, P; Jollet, C; Jullian, S; Kochetov, O I; Kovalenko, V; Lalanne, D; Leccia, F; Longuemare, C; Marquet, C; Mauger, F; Nicholson, H W; Ohsumi, H; Piquemal, F; Reyss, J L; Sarazin, X; Shitov, Yu P; Simard, L C; Stekl, I; Suhonen, J; Sutton, C S; Szklarz, G; Timkin, V; Tretyak, V I; Umatov, V I; Vàla, L; Vanyushin, I A; Vasilyev, V; Vorobel, V; Vylov, T D; Hubert, Ph.; Marquet, Ch.; Shitov, Yu.; Vylov, Ts.

    2003-01-01

    The background induced by radioactive impurities of $^{208}\\rm Tl$ and $^{214}\\rm Bi$ in the source of the double beta experiment NEMO-3 has been investigated. New methods of data analysis which decrease the background from the above mentioned contamination are identified. The techniques can also be applied to other double beta decay experiments capable of measuring independently the energies of the two electrons.

  5. Momentum analyzers DCBA for neutrinoless double beta decay experiments

    International Nuclear Information System (INIS)

    Momentum analyzers called Drift Chamber Beta-ray Analyzer (DCBA) are being developed at KEK in order to search for neutrinoless double beta decays of nuclei. A test prototype, DCBA-T2, has been constructed to confirm the principle detecting electron tracks in a uniform magnetic field. Another prototype, DCBA-T3, is now under construction to improve the energy resolution. The test results and the present statuses of these prototypes are presented.

  6. Momentum analyzers DCBA for neutrinoless double beta decay experiments

    Energy Technology Data Exchange (ETDEWEB)

    Ishihara, Nobuhiro, E-mail: nobuhiro.ishihara@kek.j [High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan)

    2010-11-01

    Momentum analyzers called Drift Chamber Beta-ray Analyzer (DCBA) are being developed at KEK in order to search for neutrinoless double beta decays of nuclei. A test prototype, DCBA-T2, has been constructed to confirm the principle detecting electron tracks in a uniform magnetic field. Another prototype, DCBA-T3, is now under construction to improve the energy resolution. The test results and the present statuses of these prototypes are presented.

  7. Neutron beta decay and the right-handed current problem

    Energy Technology Data Exchange (ETDEWEB)

    Gaponov, Yu.V.; Shul' gina, N.B.; Spivak, P.E. (Gosudarstvennyj Komitet po Ispol' zovaniyu Atomnoj Ehnergii SSSR, Moscow (USSR). Inst. Atomnoj Ehnergii)

    1991-01-10

    The renormalization of the axial-vector coupling constant, {lambda}=g{sub A}/g{sub V}, extracted from the neutron lifeime ({lambda}{sub tau}) and from the neutron beta decay asymmetry ({lambda}{sub c}) is considered carefully in the standard model of the electroweak interaction {lambda}{sub tau} should be equal to {lambda}{sub c}. According to recent experimental data on neutron beta decay, {lambda}{sub tau} and {lambda}{sub c} seem to differ from each other. This fact is explained in the framework of the manifestly left-right symmetric model SU(2){sub L}xSU(2){sub R}xU(1). The possibility of the existence of the right-handed current in the neutron beta decay is pointed out. A joint analysis of neutron beta decay and muon decay is performed, the right-handed current parameters are estimated. The axial-vector constant renormalization ({lambda}{sub N}) by right-handed currents is evaluated. (orig.)D.

  8. Perturbative description of nuclear double beta decay transitions

    OpenAIRE

    Bes, D. R.; Civitarese, O.; Scoccola, N.N.

    1998-01-01

    A consistent treatment of intrinsic and collective coordinates is applied to the calculation of matrix elements describing nuclear double beta decay transitions. The method, which was developed for the case of nuclear rotations, is adapted to include isospin and number of particles degrees of freedom. It is shown that the uncertainties found in most models, in dealing with these decay modes, are largely due to the mixing of physical and spurious effects in the treatment of isospin dependent i...

  9. Nuclear Structure Aspects of Neutrinoless Double Beta Decay

    CERN Document Server

    Brown, B A; Sen'kov, R A

    2014-01-01

    We decompose the neutrinoless double-beta decay matrix elements into sums of products over the intermediate nucleus with two less nucleons. We find that the sum is dominated by the J^pi=0^+ ground state of this intermediate nucleus for both the light and heavy neutrino decay processes. This provides a new theoretical tool for comparing and improving nuclear structure models. It also provides the connection to two-nucleon transfer experiments.

  10. The Standard Model and the neutron beta-decay

    CERN Document Server

    Abele, H

    2000-01-01

    This article reviews the relationship between the observables in neutron beta-decay and the accepted modern theory of particle physics known as the Standard Model. Recent neutron-decay measurements of various mixed American-British-French-German-Russian collaborations try to shed light on the following topics: the coupling strength of charged weak currents, the universality of the electroweak interaction and the origin of parity violation.

  11. Double beta decays and fundamental laws studied by ultra rare-decay nuclear spectroscopy

    International Nuclear Information System (INIS)

    Recent works on double beta decays and on fundamental laws, which are studied by means of the ultra rare-decay nuclear spectroscopy, are described. Subjects discussed here include unique features of the nuclear spectroscopic method for studying basic problems of nuclear and particle interactions, neutrinos and weak interactions studied by double-beta and gamma spectroscopy, weakly interacting dark matters studied by nuclear recoil spectroscopy, exotic K X-ray transitions and charge non-conservation, and exotic nuclear transitions associated with nucleon decays. (author)

  12. Beta-decay of 20Mg

    International Nuclear Information System (INIS)

    The β-decay of 20Mg was investigated. A secondary beam of 20Mg ions, produced in reactions between a 95 A x MeV 24Mg-beam and a nat.Ni-target, was isotopically separated by means of the LISE3 spectrometer at GANIL. This secondary beam was implanted into a silicon detector array surrounded by germanium γ-detectors. The β-delayed proton and γ-ray data, measured for this short-lived nucleus (T1/2=95±3 ms), were incorporated into an improved 20Mg→20Na decay scheme. The 2645 keV level in 20Na is of importance for the breakout from the astrophysical hot CNO-cycle and the onset of the rapid proton capture process via the reaction 19Ne(p,γ)20Na. An upper limit of 0.1% for the β-decay feeding of the 2645 keV level and a lower limit for the corresponding log ft value of 6.24 were determined. The implications of this result for the spin and parity assignment of the 2645 keV state are discussed. Concerning the isobaric multiplet mass equation no significant deviation from its quadratic form was found. By comparing the 20Mg β-decay into the proton-unbound 3001 keV state in 20Na and the isospin-mirrored decay into the particle-bound 3488 keV level in 20F, an asymmetry ft+/ft--1=1.69-0.65+0.86 was observed. (orig.)

  13. Measuring pion beta decay with high-energy pion beams

    International Nuclear Information System (INIS)

    Improved measurements of the pion beta decay rate are possible with an intense high-energy pion beam. The rate for the decay π+ → π0e+vε is predicted by the Standard Model (SM) to be R(π+ → π0e+vε) = 0.3999±0.0005 s-1. The best experimental number, obtained using in-flight decays, is R(π+ → π0e+vε) = 0.394 ± 0.015 s-1. A precise measurement would test the SM by testing the unitarity of the Cabibbo-Kobayashi-Maskawa matrix for which one analysis of the nuclear beta decay data has shown a 0.4% discrepancy. Several nuclear correction factors, needed for nuclear decay, are not present for pion beta decay, so that an experiment at the 0.2% level would be a significant one. Detailed study of possible designs will be needed, as well as extensive testing of components. The reduction of systematic errors to the 0.1% level can only be done over a period of years with a highly stable apparatus and beam. At a minimum, three years of occupancy of a beam line, with 800 hours per year, would be required

  14. Ordinary muon capture as a probe of virtual transitions of $\\beta\\beta$ decay

    CERN Document Server

    Kortelainen, M

    2002-01-01

    A reliable theoretical description of double-beta-decay processes needs a possibility to test the involved virtual transitions against experimental data. Unfortunately, only the lowest virtual transition can be probed by the traditional electron-capture or $\\beta^-$-decay experiments. In this article we propose that calculated amplitudes for many virtual transitions can be probed by experiments measuring rates of ordinary muon capture (OMC) to the relevant intermediate states. The first results from such experiments are expected to appear soon. As an example we discuss the $\\beta\\beta$ decays of $^{76}$Ge and $^{106}$Cd and the corresponding OMC for the $^{76}$Se and $^{106}$Cd nuclei in the framework of the proton-neutron QRPA with realistic interactions. It is found that the OMC observables, just like the $2\

  15. The beta strength function structure in \\beta + decay of lutecium, thulium and cesium isotopes

    CERN Document Server

    Alkhazov, G D; Naumov, Yu V; Orlov, S Yu; Vitman, V D

    1981-01-01

    The spectra of total gamma -absorption in the decays of some lutetium, thulium and cesium isotopes have been measured. The probabilities for level population in the decay of the isotopes have been determined. The deduced beta strength functions reveal pronounced structure. Calculations of the strength functions using the Saxon-Woods potential and the residual Gamow-Teller interaction are presented. It is shown that in beta /sup +/ decay of light thulium and cesium isotopes the strength function comprises more than 70% of the Gamow-Teller excitations with mu /sub tau /=+1. This result is the first direct observation of the Gamov-Teller resonance in beta /sup +/ decay of nuclei with T/sub z/>0. (21 refs).

  16. EXO the Enriched Xenon Observatory for Double Beta Decay

    CERN Document Server

    Wamba, K

    2002-01-01

    EXO is a search for neutrinoless double beta decay in 136Xe. An active R&D program for a 10 ton, enriched 136Xe liquid phase detector is now underway. Current research projects are: decay product extraction, Xe purity studies, energy resolution studies, and Ba+ ion laser-tagging. By extracting and laser-tagging the Xe decay product (136Ba) and optimizing the energy resolution in liquid Xe, half lives of up to 5.0x10^28yr will be ultimately probed, corresponding to a sensitivity to Majorana n masses > ~10meV.

  17. Results on neutrinoless double beta decay from GERDA phase I

    CERN Document Server

    CERN. Geneva

    2013-01-01

    After motivating searches of double beta decay and lepton number violation details about the construction, operation and analysis of GERDA will be given. Results of the recently completed phase I of data taking will then be presented and interpreted. Finally an outlook on future plans will be given.

  18. Computer code for double beta decay QRPA based calculations

    International Nuclear Information System (INIS)

    The computer code developed by our group some years ago for the evaluation of nuclear matrix elements, within the QRPA and PQRPA nuclear structure models, involved in neutrino-nucleus reactions, muon capture and β± processes, is extended to include also the nuclear double beta decay

  19. Evaluation of beta-decay III. The complex gamma function

    International Nuclear Information System (INIS)

    Two real, analytical, approximations for the square of the modulus of the complex gamma function as it appears in F(Z, W), the Fermi function for beta-decay, are evaluated; an accuracy bettering 10-4% can easily be achieved for all electron energies throughout the periodic table. (author). 3 refs., 1 tab., 7 figs

  20. A cryogenic microcalorimeter for tritium beta decay experiments

    International Nuclear Information System (INIS)

    Recent tritium beta decay spectrometer experiments have produced puzzling results, making it desirable to perform a similar experiment with a completely different type of detector. Cryogenic microcalorimeters offer a possible detector technology for this type of experiment. Presented here is a design for, and results of experiments with, a cryogenic microcalorimeter designed for use in tritium beta decay experiments. The biggest challenge in designing a microcalorimeter for beta decay experiments is the speed at which the detector operates. A fast detector is essential to obtain the necessary statistics near the beta spectrum endpoint. .The detector was designed with a normal metal absorber and a bilayer super-conducting transition-edge sensor. These design elements are meant to minimize the pulse rise time and decay time, respectively. Two different detector designs were built and tested in order to determine their operating parameters. These operating parameters were compared to a model describing the operation of these devices and were shown to be in reasonable agreement with it. The model predicts that the detector properties can be improved to the point where a tritium neutrino mass experiment can be performed. Suggestions are given for design modifications that will allow this level of performance. (author)

  1. Forbidden unique beta-decays and neutrino mass

    Energy Technology Data Exchange (ETDEWEB)

    Dvornický, Rastislav [Bogoliubov Laboratory of Theoretical Physics, JINR Dubna, 141980 Dubna, Moscow region, Russian Federation and Department of Nuclear Physics and Biophysics, Comenius University, Mlynská dolina F1, SK-84215 Bratislava (Slovakia); Šimkovic, Fedor [Department of Nuclear Physics and Biophysics, Comenius University, Mlynská dolina F1, SK-84215 Bratislava, Slovakia and IEAP, Czech Technical University, CZ-128 00 Prague (Czech Republic)

    2013-12-30

    The measurement of the electron spectrum in beta-decays provides a robust direct determination of the values of neutrino masses. The planned rhenium beta-decay experiment, called the “Microcalorimeter Arrays for a Rhenium Experiment” (MARE), might probe the absolute mass scale of neutrinos with the same sensitivity as the Karlsruhe tritium neutrino mass (KATRIN) experiment, which is expected to collect data in a near future. In this contribution we discuss the spectrum of emitted electrons close to the end point in the case of the first unique forbidden beta-decay of {sup 79}Se, {sup 107}Pd and {sup 187}Re. It is found that the p{sub 3/2}-wave emission dominates over the s{sub 1/2}-wave. It is shown that the Kurie plot near the end point is within a good accuracy linear in the limit of massless neutrinos like the Kurie plot of the superallowed beta-decay of {sup 3}H.

  2. MeV neutrinos in double beta decay

    OpenAIRE

    Zuber, K.

    1996-01-01

    The effect of Majorana neutrinos in the MeV mass range on the double beta decay of various isotopes is studied on pure phenomenological arguments. By using only experimental half life data, limits on the mixing parameter $U_{eh}^2$ of the order 10$^{-7}$ can be derived. Also the possible achievements of upcoming experiments and some consequences are outlined.

  3. Status and perspectives of double beta decay searches

    International Nuclear Information System (INIS)

    Double beta decay is an extremely rare process and requires half-live measurements around 1020 years for the neutrino accompanied mode, while for the neutrino-less mode much longer half-lives have to be explored. The various experimental approaches, currently considered for the search of this process, results will be presented

  4. Inner shell ionization in beta decay

    International Nuclear Information System (INIS)

    The purpose of this paper is to examine various ways to resolve the discrepancy that exists between the theoretical calculations on K-shell autoionization probabilities in #betta# decay and the measured values. The chequered history of the subject may be traced through the reviews and papers of Freedman and co workers. Suffice it to say that Isozumi et al (ISM) found that the Law and Campbell (LC) model over counted the shake-off contribution by a factor of two; this correction thus destroys the remarkable agreement between theory and experiment

  5. Searches for massive neutrinos in nuclear beta decay

    International Nuclear Information System (INIS)

    The status of searches for massive neutrinos in nuclear beta decay is reviewed. The claim by an ITEP group that the electron antineutrino mass > 17eV has been disputed by all the subsequent experiments. Current measurements of the tritium beta spectrum limit mbarνe < 10 eV. The status of the 17 keV neutrino is reviewed. The strong null results from INS Tokyo and Argonne, and deficiencies in the experiments which reported positive effects, make it unreasonable to ascribe the spectral distortions seen by Simpson, Hime, and others to a 17keV neutrino. Several new ideas on how to search for massive neutrinos in nuclear beta decay are discussed

  6. Beta-delayed neutron decay of $^{33}$Na

    CERN Document Server

    Radivojevic, Z; Caurier, E; Cederkäll, J; Courtin, S; Dessagne, P; Jokinen, A; Knipper, A; Le Scornet, G; Lyapin, V G; Miehé, C; Nowacki, F; Nummela, S; Oinonen, M; Poirier, E; Ramdhane, M; Trzaska, W H; Walter, G; Äystö, J

    2002-01-01

    Beta-delayed neutron decay of /sup 33/Na has been studied using the on-line mass separator ISOLDE. The delayed neutron spectra were measured by time-of-flight technique using fast scintillators. Two main neutron groups at 800(60) and 1020(80) keV were assigned to the /sup 33/Na decay, showing evidence for strong feeding of states at about 4 MeV in /sup 33/Mg. By simultaneous beta - gamma -n counting the delayed neutron emission probabilities P/sub 1n/ = 47(6)% and P /sub 2n/ = 13(3)% were determined. The half-life value for /sup 33 /Na, T/sub 1/2/ = 8.0(3) ms, was measured by three different techniques, one employing identifying gamma transitions and two employing beta and neutron counting. (21 refs).

  7. Measurement of double beta decay - experiments TGV and NEMO

    International Nuclear Information System (INIS)

    TGV and NEMO, two international collaboration projects are described. The TGV project deals with the double beta decay of 48Ca. In 1998, this project was augmented with the examination of the double beta decay of 106Cd - the β+β+, β+/EC, and EC/EC modes. The main objective of this experiment consists in recording the 2νEC/EC mode (0+ → 0+, ground state), giving rise to the emission of 2 gamma quanta of roughly 21 keV. The NEMO project deals with 100Mo. The main objective of the NEMO-3 experiment consists in the measurement of the half-life of the neutrinoless double decay of this nuclide (about 1025 years)

  8. Measurement of the $B^+\\rightarrow p \\bar{p} K^{+}$ Branching Fraction and Study of the Decay Dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; /Annecy, LAPP; Grauges, E.; /Barcelona, IFAE; Palano, A.; Pappagallo, M.; Pompili, A.; /Bari U. /INFN, Bari; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; /Beijing, Inst. High Energy Phys.; Eigen, G.; Ofte, I.; Stugu, B.

    2005-07-06

    With a sample of 232 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} events collected with the BABAR detector, we study the decay B{sup +} {yields} p{bar p}K{sup +} excluding charmonium decays to p{bar p}. We measure a branching fraction {Beta}(B{sup +} {yields} p{bar p}K{sup +}) = (6.7 {+-} 0.5 {+-} 0.4) x 10{sup -6}. An enhancement at low p{bar p} mass is observed and the Dalitz plot asymmetry suggests dominance of the penguin amplitude in this B decay. We search for a pentaquark candidate {Theta}*{sup ++} decaying into pK{sup +} in the mass range 1.43 to 2.00 GeV/c{sup 2} and set limits on {Beta}(B{sup +} {yields} {Theta}*{sup ++} {bar p}) x {Beta}({Theta}*{sup ++} {yields} pK{sup +}) at the 10{sup -7} level.

  9. Determination restitution coefficient of branching fraction of Dο Meson ≤ Κ- π+ decay

    International Nuclear Information System (INIS)

    We measure the restitution coefficient of branching fraction for Dο Meson ≥ Κ-π+ decay using the partial reconstruction of Bο->D*+Xl-vl decay, for branching fraction we use the charge lepton and the soft pion from the D*+->Dοπ+. We will compare the branching fraction in based on a data sample of 230 million BB pairs collected at γ(4s) resonance with BABAR detector at PEP II asymmetric-energy B factory at SLAC with our theory result, after determination of branching fraction we use mass of soft pion and mass of lepton and energy soft pion and energy soft lepton for finding restitution of coefficient

  10. Beta decay of the exotic $T_z$ = -2 nuclei $^{48}$Fe, $^{52}$Ni and $^{56}$Zn

    CERN Document Server

    Orrigo, S E A; Fujita, Y; Gelletly, W; Agramunt, J; Algora, A; Ascher, P; Bilgier, B; Blank, B; Cáceres, L; Cakirli, R B; Ganioğlu, E; Gerbaux, M; Giovinazzo, J; Grévy, S; Kamalou, O; Kozer, H C; Kucuk, L; Kurtukian-Nieto, T; Molina, F; Popescu, L; Rogers, A M; Susoy, G; Stodel, C; Suzuki, T; Tamii, A; Thomas, J C

    2016-01-01

    The results of a study of the beta decays of three proton-rich nuclei having $T_z$ = -2, namely $^{48}$Fe, $^{52}$Ni and $^{56}$Zn, produced in an experiment carried out at GANIL, are reported. In all the cases we have extracted the half-lives and the total $\\beta$-delayed proton emission branching ratios. We have measured the individual $\\beta$-delayed protons and $\\beta$-delayed $\\gamma$ rays with their branching ratios. Decay schemes have been determined for the three nuclei, and new energy levels are identified in the corresponding daughter nuclei. Competition between $\\beta$-delayed protons and gammas is observed in the de-excitation of the $T$ = 2 Isobaric Analogue States in all three cases. Absolute Fermi and Gamow-Teller transition strengths have been determined. The mass excesses of the nuclei under study have been deduced. In addition, we discuss in detail the data analysis taking as a test case $^{56}$Zn, where the exotic $\\beta$-delayed $\\gamma$-proton decay has been observed.

  11. Three-dimensional drift chambers of the DCBA experiment for neutrinoless double beta decay search

    Energy Technology Data Exchange (ETDEWEB)

    Ishikawa, T., E-mail: ishikawat@hakone.phys.metro-u.ac.j [Tokyo Metropolitan University, Hachioji, Tokyo 192-0398 (Japan); Igarashi, H.; Sumiyoshi, T. [Tokyo Metropolitan University, Hachioji, Tokyo 192-0398 (Japan); Ishihara, N.; Iwai, G.; Iwase, H.; Kato, Y.; Kawai, M.; Kondou, Y.; Haruyama, T.; Inagaki, T.; Makida, Y.; Ohama, T.; Takahashi, K.; Yamada, Y. [High Energy Accel, Research Organization (KEK), Tsukuba, Ibaraki 305-0801 (Japan); Tashiro, E.; Ishizuka, T. [Shizuoka University, Naka, Hamamatsu, Shizuoka 432-8011 (Japan); Kitamura, S. [Nihon Institute of Medical Science, Iruma-gun, Saitama 350-0435 (Japan); Teramoto, Y. [Osaka City University, Sumiyoshi, Osaka 558-8585 (Japan); Nakano, I. [Okayama University, Okayama 700-8530 (Japan)

    2011-02-01

    The aim of the DCBA (Drift Chamber Beta-ray Analyzer) experiment is to search for neutrinoless double beta decay (0{nu}{beta}{beta}). The half-life of 0{nu}{beta}{beta} is expected to give us the information of Majorana nature and the absolute mass scale of neutrinos. A prototype test apparatus DCBA-T2 has the energy resolution of about 150 keV (FWHM) around 1 MeV. In order to check the detector performance, engineering runs detecting double beta decay of {sup 100}Mo started in May 2009 using natural Mo, which contains 9.6% of {sup 100}Mo. Ten candidates of the double beta decay ({beta}{beta}) have been detected so far. It has been found that the background events due to {sup 214}Bi decay are distinguishable from the double beta decays by detecting {alpha}-particles from {sup 214}Po.

  12. Contribution to decay heat calculation: fission product mean beta and gamma assessment

    International Nuclear Information System (INIS)

    Following a reactor shutdown, after the fission chain process has completely faded out, a significant quantity of energy (around seven per cent of the total power of the reactor) continues to be generated in the core. This is known as residual power or decay heat. The principal source of this energy is due to the radioactive decay of fission products and is at any time equal to the sum of the powers released by these different nuclei (P = Σ = Pi). Each of the powers Pi is the product of three terms: the concentration of the relevant nuclide, its decay constant and its mean decay energy. The evaluation of the first two term is straightforward. On the other hand the evaluation of the mean energies presents some difficulties due to a lack of data in beta and gamma spectra of some fission products. This study intends, after a critical analysis of the current method of evaluation of the mean energies, to propose a new model for this calculation. The new model tested on several well known nuclides, has been proved correct and precise. It has then been applied to approximatively sixty nuclides among the lesser known ones. The results obtained have lead to a better prediction of both beta and gamma ray components of the residual power. Consequently, this new model, which allows to take into account the lack of beta branching ratio corresponding to the highest levels of the product nucleus in the beta decay reaction, can be adopted to replace the current method, for calculation of the mean energies of fission products, especially in the case of the lesser known nuclides

  13. Beta-decay rate and beta-delayed neutron emission probability of improved gross theory

    Science.gov (United States)

    Koura, Hiroyuki

    2014-09-01

    A theoretical study has been carried out on beta-decay rate and beta-delayed neutron emission probability. The gross theory of the beta decay is based on an idea of the sum rule of the beta-decay strength function, and has succeeded in describing beta-decay half-lives of nuclei overall nuclear mass region. The gross theory includes not only the allowed transition as the Fermi and the Gamow-Teller, but also the first-forbidden transition. In this work, some improvements are introduced as the nuclear shell correction on nuclear level densities and the nuclear deformation for nuclear strength functions, those effects were not included in the original gross theory. The shell energy and the nuclear deformation for unmeasured nuclei are adopted from the KTUY nuclear mass formula, which is based on the spherical-basis method. Considering the properties of the integrated Fermi function, we can roughly categorized energy region of excited-state of a daughter nucleus into three regions: a highly-excited energy region, which fully affect a delayed neutron probability, a middle energy region, which is estimated to contribute the decay heat, and a region neighboring the ground-state, which determines the beta-decay rate. Some results will be given in the presentation. A theoretical study has been carried out on beta-decay rate and beta-delayed neutron emission probability. The gross theory of the beta decay is based on an idea of the sum rule of the beta-decay strength function, and has succeeded in describing beta-decay half-lives of nuclei overall nuclear mass region. The gross theory includes not only the allowed transition as the Fermi and the Gamow-Teller, but also the first-forbidden transition. In this work, some improvements are introduced as the nuclear shell correction on nuclear level densities and the nuclear deformation for nuclear strength functions, those effects were not included in the original gross theory. The shell energy and the nuclear deformation for

  14. Precision Measurement of the Radiative $\\Beta$ Decay of the Free Neutron

    OpenAIRE

    Bales, M. J.; Alarcon, R.; Bass, C. D.; Beise, E. J.; Breuer, H.; Byrne, J; Chupp, T. E.; Coakley, K. J.; Cooper, R. L.; Dewey, M. S.; Gardner, S.; Gentile, T. R.; He, D.; Mumm, H. P.; Nico, J. S.

    2016-01-01

    The standard model predicts that, in addition to a proton, an electron, and an antineutrino, a continuous spectrum of photons is emitted in the $\\beta$ decay of the free neutron. We report on the RDK II experiment which measured the photon spectrum using two different detector arrays. An annular array of bismuth germanium oxide scintillators detected photons from 14 to 782~keV. The spectral shape was consistent with theory, and we determined a branching ratio of 0.00335 $\\pm$ 0.00005 [stat] $...

  15. Beta decay of polarized nuclei and the decay asymmetry of 8Li

    International Nuclear Information System (INIS)

    Under certain conditions, it is possible to produce vector-polarized radioactive nuclei in reactions with a polarized projectile and an unpolarized target. Using the intense polarized beams at the University of Wisconsin, the authors have begun a program to study the weak interaction through the beta decay of polarized nuclei produced in this way. Such experiments bear on tests of CVC in light nuclei, sensitive searches for second-class weak currents, and measurements of the weak vector-coupling constant. One may also deduce the values of certain matrix elements. Our effort is presently centering on a study of the energy dependence of the beta-decay asymmetry of 8Li

  16. New generation of experiments searching for neutrinoless double beta decay

    International Nuclear Information System (INIS)

    Full text: The search for neutrinoless double beta decay is one of the central research topics in fundamental physics. In fact, the observation of neutrinoless double beta decay would not only establish the Majorana nature of the neutrino but also provide a measurement of its effective mass ee> as well as fix the hierarchy of neutrino spectrum. The next generation of experiments aims to probe the effective Majorana neutrino mass down to few 10 MeV, as predicted by oscillation experiments in case of the inverse mass hierarchy. In this talk the most part of the upcoming experiments are reviewed. The sensitivity of the upcoming experiments depend therefore primarily on the available mass of double beta isotopes and the experimental conditions. In particular, the achievable background suppression and the detection efficiency will be decisive for their success. Experimental consideration as detection efficiency and background suppression will determine the final sensitivity of the different experimental approaches. The first of the next generation experiments, such as GERDA at LNGS, Italy, EXO at WIPP, USA and KamLAND-Zen in Japan, became operational recently. New projects like SuperNEMO, MAJORANA, CUORE and others will start in the nearest future. The future development of the field will strongly depend on the results of the upcoming experiments. If neutrinoless double beta decay is observed at the 1 eV scale, as claimed by part of the Heidelberg Moscow experiment, the decay could be studied with high precision with many different isotopes and different techniques. The effective mass could be measured with accuracy and the leading term governing the decay mode identified. In case that the claim is refuted, at least two experiments with about one ton of isotopes and zero background in the region of interest for several year x ton of exposure are required to cover the full mass range down to 10 MeV predicted by oscillation experiments for the inverse mass hierarchy

  17. Neutrino masses from double-beta decay calculations

    CERN Document Server

    Stoica, S

    2002-01-01

    The neutrinoless double-beta decay (0 nu beta beta) matrix elements (ME) for the nuclei with A = 76, 82, 96, 100, 116, 128, 130 and 136 are compared with four different quasi random phase approximation (QRPA) - based method, i.e. the proton-neutron QRPA (pnQRPA), the renormalized proton-neutron QRPA (pnRQRPA), the full RQRPA and the second-QRPA (SQRPA) and using two single-particle basis. From a comparative analysis of the results we show that the uncertainties in the calculation of the ME can be limited to 50% from their values. Further, taking the most recent available limits for the neutrinoless half-lives, we deduce new upper limits for the neutrino mass parameter. Also, there are estimated for each nucleus scales for the (0 nu beta beta) decay half-lives that the experiments should reach for measuring neutrino masses around 0.39 eV. This value was derived from the first experimental evidence of this mode reported very recently by the Heidelberg-Moscow experiment. These estimation give us an indication on...

  18. Search for the l-forbidden beta decay /sup 207/Tl→/sup 207/Pb(570 keV)

    International Nuclear Information System (INIS)

    We have searched for the l-forbidden beta decay of /sup 207/Tl to the first excited state of /sup 207/Pb by looking for 570-keV γ rays following the decay of /sup 207/Tl. We find a branching ratio of (2.4 +- 5.6) x 10/sup -7/ per /sup 207/Tl decay. This limit could provide a test for calculations of core polarization, meson exchange, and Δ excitation effects. We also find a branch of (0.54 +- 0.05)% for the l-forbidden M1 transition /sup 207/Pb(898,(3/2-→570,(5/2-) and measure the intensities of γ rays emitted following the decay of /sup 211/Pb

  19. Study of the ${\\beta}$-decay of $^{12}$B

    CERN Multimedia

    2002-01-01

    We propose to study the ${\\beta}$-decay of $^{12}$B with a modern segmented Si-detector array to get new and much improved information on states in $^{12}$C above the ${\\alpha}$-threshold. These states mainly decay into final states of three ${\\alpha}$-particles and their study therefore is a challenge for nuclear spectroscopy. The properties of these states is of high current interest for nuclear astrophysics and for the nuclear many-body problem in general. We ask for a total of 15 shifts.

  20. The GERDA Neutrinoless Double Beta-Decay Experiment

    International Nuclear Information System (INIS)

    Neutrinoless double beta (0νββ)-decay is the key process to gain understanding of the nature of neutrinos. The GErmanium Detector Array (GERDA) is designed to search for 0νββ-decay of the isotope 76Ge. Germanium crystals enriched in 76Ge, acting as source and detector simultaneously, will be submerged directly into an ultra pure cooling medium that also serves as a radiation shield. This concept will allow for a reduction of the background by up to two orders of magnitudes with respect to earlier experiments

  1. 31Cl beta decay and the 30P31S reaction rate in nova nucleosynthesis

    Science.gov (United States)

    Bennett, Michael; Wrede, C.; Brown, B. A.; Liddick, S. N.; Pérez-Loureiro, D.; NSCL e12028 Collaboration

    2016-03-01

    The 30P31S reaction rate is critical for modeling the final isotopic abundances of ONe nova nucleosynthesis, identifying the origin of presolar nova grains, and calibrating proposed nova thermometers. Unfortunately, this rate is essentially experimentally unconstrained because the strengths of key 31S proton capture resonances are not known, due to uncertainties in their spins and parities. Using a 31Cl beam produced at the National Superconducting Cyclotron Laboratory, we have populated several 31S states for study via beta decay and devised a new decay scheme which includes updated beta feedings and gamma branchings as well as multiple states previously unobserved in 31Cl beta decay. Results of this study, including the unambiguous identification due to isospin mixing of a new l = 0 , Jπ = 3 /2+ 31S resonance directly in the middle of the Gamow Window, will be presented, and significance to the evaluation of the 30P31S reaction rate will be discussed. Work supported by U.S. Natl. Sci. Foundation (Grants No. PHY-1102511, PHY-1404442, PHY-1419765, and PHY-1431052); U.S. Dept. of Energy, Natl. Nucl. Security Administration (Award No. DE-NA0000979); Nat. Sci. and Eng. Research Council of Canada.

  2. Neutrinoless double $\\beta$ decay and low scale leptogenesis

    CERN Document Server

    Drewes, Marco

    2016-01-01

    The extension of the Standard Model by right handed neutrinos with masses in the GeV range can simultaneously explain the observed neutrino masses via the seesaw mechanism and the baryon asymmetry of the universe via leptogenesis. It has previously been claimed that the requirement for successful baryogenesis implies that the rate of neutrinoless double $\\beta$ decay in this scenario is always smaller than the standard prediction from light neutrino exchange alone. In contrast, we find that the rate for this process can also be enhanced due to a dominant contribution from heavy neutrino exchange. In a small part of the parameter space it even exceeds the current experimental limit, while the properties of the heavy neutrinos are consistent with all other experimental constraints and the observed baryon asymmetry is reproduced. This implies that neutrinoless double $\\beta$ decay experiments have already started to rule out part of the leptogenesis parameter space that is not constrained by any other experiment...

  3. The Majorana Demonstrator search for neutrinoless double beta decay

    CERN Document Server

    Cuesta, C; Detwiler, J A; Gruszko, J; Guinn, I S; Leon, J; Robertson, R G H; Abgrall, N; Bradley, A W; Chan, Y-D; Mertens, S; Poon, A W P; Vetter, K; Arnquist, I J; Hoppe, E W; Kouzes, R T; Orrell, J L; Avignone, F T; Barabash, A S; Konovalov, S I; Yumatov, V; Bertrand, F E; Galindo-Uribarri, A; Radford, D C; Varner, R L; Yu, C -H; Brudanin, V; Shirchenko, M; Vasilyev, S; Yakushev, E; Zhitnikov, I; Busch, M; Caldwell, T S; Gilliss, T; Henning, R; Howe, M A; MacMullin, J; Meijer, S J; O'Shaughnessy, C; Rager, J; Shanks, B; Trimble, J E; Vorren, K; Xu, W; Christofferson, C D; Dunagan, C; Suriano, A M; Chu, P -H; Elliott, S R; Massarczyk, R; Rielage, K; White, B R; Efremenko, Yu; Lopez, A M; Ejiri, H; Fullmer, A; Giovanetti, G K; Green, M P; Guiseppe, V E; Tedeschi, D; Wiseman, C; Jasinski, B R; Keeter, K J; Kidd, M F; Martin, R D; Romero-Romero, E; Wilkerson, J F

    2016-01-01

    The MAJORANA Collaboration is constructing the MAJORANA DEMONSTRATOR, an ultra-low background, modular, HPGe detector array with a mass of 44.8-kg (29.7 kg enriched >88% in Ge-76) to search for neutrinoless double beta decay in Ge-76. The next generation of tonnescale Ge-based neutrinoless double beta decay searches will probe the neutrino mass scale in the inverted-hierarchy region. The MAJORANA DEMONSTRATOR is envisioned to demonstrate a path forward to achieve a background rate at or below 1 count/tonne/year in the 4 keV region of interest around the Q-value of 2039 keV. The MAJORANA DEMONSTRATOR follows a modular implementation to be easily scalable to the next generation experiment. First data taken with the DEMONSTRATOR are introduced here.

  4. Collective Effect Studies of a Beta Beam Decay Ring

    CERN Document Server

    Hansen, Christian

    2011-01-01

    The Beta Beam, the concept of generating a pure and intense (anti) neutrino beam by letting accelerated radioactive ions beta decay in a storage ring called the Decay Ring (DR), is the basis of one of the proposed next generation neutrino oscillation facilities, necessary for a complete study of the neutrino oscillation parameter space. Sensitivities of the unknown neutrino oscillation parameters depend on the DR's ion intensity and of its duty factor (the filled ratio of the ring). Different methods, including analytical calculations and multiparticle tracking simulations, were used to estimate the DR's potential to contain enough ions in as small a part of the ring as needed for the sensitivities. Studies of transverse blow up of the beams due to resonance wake fields show that a very challenging upper limit of the transverse broadband impedance is required to avoid instabilities and beam loss.

  5. Collective Effect Studies of a Beta Beam Decay Ring

    International Nuclear Information System (INIS)

    The Beta Beam, the concept of generating a pure and intense (anti) neutrino beam by letting accelerated radioactive ions beta decay in a storage ring called the Decay Ring (DR), is the basis of one of the proposed next generation neutrino oscillation facilities, necessary for a complete study of the neutrino oscillation parameter space. Sensitivities of the unknown neutrino oscillation parameters depend on the DR's ion intensity and of its duty factor (the filled ratio of the ring). Different methods, including analytical calculations and multiparticle tracking simulations, were used to estimate the DR's potential to contain enough ions in as small a part of the ring as needed for the sensitivities. Studies of transverse blow up of the beams due to resonance wake fields show that a very challenging upper limit of the transverse broadband impedance is required to avoid instabilities and beam loss.

  6. A combined limit for neutrinoless double-beta decay

    CERN Document Server

    Guzowski, Pawel

    2015-01-01

    The search for neutrinoless double-beta decay is important in determining the Majorana nature of the neutrino, and also in establishing if lepton number is violated. In this work, we combine the published data from five independent neutrinoless double-beta decay experiments: CUORICINO, EXO, GERDA, KamLAND-Zen and NEMO-3. As these experiments use different isotope sources, the relative signal normalisation between them depends on the Nuclear Matrix Element (NME) calculations used. The combined limits for the Majorana neutrino mass for 5 different NME models range from 130-310 meV. The combined mass limits can offer an improvement over the individual experiments of up to 25%, depending on the NME model.

  7. Nuclear Matrix Elements for the $\\beta\\beta$ Decay of the $^{76}$Ge

    CERN Document Server

    Brown, B A; Horoi, M

    2015-01-01

    The nuclear matrix elements for two-neutrino double-beta (2 n$\\beta\\beta$ ) and zero-neutrino double-beta (0 n$\\beta\\beta$) decay of 76 Ge are evaluated in terms of the configuration interaction (CI), quasiparticle random phase approximation (QRPA) and interacting boson model (IBM) methods. We show that the decomposition of the matrix elements in terms of interemediate states in 74 Ge is dominated by ground state of this nucleus. We consider corrections to the CI results that arise from configurations admixtures involving orbitals out-side of the CI configuration space by using results from QRPA, many-body-perturbation theory, and the connections to related observables. The CI two-neutrino matrix element is reduced due to the inclusion of spin-orbit partners, and to many-body correlations connected with Gamow-Teller beta decay. The CI zero-neutrino matrix element for the heavy neutrino is enhanced due to particle-particle correlations that are connected with the odd-even oscillations in the nuclear masse...

  8. BETA DECAY OPENS THE WAY TO WEAK INTERACTIONS

    OpenAIRE

    Amaldi, E.

    1982-01-01

    After a short introduction with some personal recollection, the author summarizes, in Sect 2, the main points of Fermi's theory of beta decay and of the neutrino hypothesis first proposed by Pauli. The successive Sections refer to : a few extensions and modifications of this theory (Sect 3), various experimental investigations carried out in the 30s for testing Pauli's hypothesis and Fermi's approach (Sect 4), further attempts, refinements and proposals (Sect 5) and a few fundamental step for...

  9. Neutrinoless double beta decay search with cuoricino and cuore experiments

    International Nuclear Information System (INIS)

    Cuoricino is a bolometric experiment on Neutrinoless Double Beta Decay (ον-DBD) . With its 40.7 kg mass of TeO2 it is the most massive (ον)-DBD presently running and it has proven the feasibility of the CUORE experiment, whose aim is to be sensitive to the effective neutrino mass down to few tens of me V. We report here latest Cuoricino results and prospects for the future CUORE experiment

  10. Beta Decay: A Physics Garden of Earthly Delights

    Science.gov (United States)

    Robertson, R. G. Hamish

    2014-03-01

    From the beginning, beta decay has tormented and delighted us with puzzles and enlightenment. A significant part of our present understanding of subatomic physics has emerged from the experimental and theoretical struggle with its mysteries. We reflect on several of the epic victories in this struggle, and look ahead to where ongoing research might lead us in the understanding of fundamental symmetries and neutrinos. Research supported under DOE grant DE-FG02-97ER41020.

  11. The Effect of Cancellation in Neutrinoless Double Beta Decay

    CERN Document Server

    Pascoli, Silvia; Wong, Steven

    2013-01-01

    In light of recent experimental results, we carefully analyze the effects of interference in neutrinoless double beta decay, when more than one mechanism is operative. We assume a complete cancellation is at work for $^{136}\\rm{Xe}$, and find its implications on the half-life of other isotopes, such as $^{76}\\rm{Ge}$. For definiteness, we consider the role of light and heavy sterile neutrinos. In this case, the effective Majorana mass parameter can be redefined to take into account all contributions and its value gets suppressed. Hence, larger values of neutrino masses are required for the same half-life. The canonical light neutrino contribution can not saturate the present limits of half-lives or the positive claim of observation of neutrinoless double beta decay, once the stringent bounds from cosmology are taken into account. For the case of cancellation, where all the sterile neutrinos are heavy, the tension between the results from neutrinoless double beta decay and cosmology becomes more severe. We sho...

  12. Neutrino masses and Neutrinoless Double Beta Decay: Status and expectations

    CERN Document Server

    Cremonesi, Oliviero

    2010-01-01

    Two most outstanding questions are puzzling the world of neutrino Physics: the possible Majorana nature of neutrinos and their absolute mass scale. Direct neutrino mass measurements and neutrinoless double beta decay (0nuDBD) are the present strategy to solve the puzzle. Neutrinoless double beta decay violates lepton number by two units and can occurr only if neutrinos are massive Majorana particles. A positive observation would therefore necessarily imply a new regime of physics beyond the standard model, providing fundamental information on the nature of the neutrinos and on their absolute mass scale. After the observation of neutrino oscillations and given the present knowledge of neutrino masses and mixing parameters, a possibility to observe 0nuDBDD at a neutrino mass scale in the range 10-50 meV could actually exist. This is a real challenge faced by a number of new proposed projects. Present status and future perpectives of neutrinoless double-beta decay experimental searches is reviewed. The most impo...

  13. Sensitivity of CUORE to Neutrinoless Double-Beta Decay

    Energy Technology Data Exchange (ETDEWEB)

    CUORE; Alessandria, F.; Andreotti, E.; Ardito, R.; Arnaboldi, C.; Avignone III, F. T.; Balata, M.; Bandac, I.; Banks, T. I.; Bari, G.; Beeman, J.; Bellini, F.; Bersani, A.; Biassoni, M.; Bloxham, T.; Brofferio, C.; Bryant, A.; Bucci, C.; Cai, X. Z.; Canonica, L.; Capelli, S.; Carbone, L.; Cardani, L.; Carrettoni, M.; Casali, N.; Chott, N.; Clemenza, M.; Cosmelli, C.; Cremonesi, O.; Creswick, R. J.; Dafinei, I.; Dally, A.; Biasi, A. De; Decowski, M. P.; Deninno, M. M.; Waard, A. de; Domizio, S. Di; Ejzak, L.; Faccini, R.; Fang, D. Q.; Farach, H. A.; Ferri, E.; Ferroni, F.; Fiorini, E.; Foggetta, L.; Franceschi, M. A.; Freedman, S. J.; Frossati, G.; Fujikawa, B. K.; Giachero, A.; Gironi, L.; Giuliani, A.; Gorla, P.; Gotti, C.; Guardincerri, E.; Gutierrez, T. D.; Haller, E. E.; Han, K.; Heeger, K. M.; Huang, H. Z.; Ichimura, K.; Kadel, R.; Kazkaz, K.; Keppel, G.; Kogler, L.; Kolomensky, Yu. G.; Kraft, S.; Lenz, D.; Li, Y. L.; Liu, X.; Longo, E.; Ma, Y. G.; Maiano, C.; Maier, G.; Maino, M.; Mancini, C.; Martinez, C.; Martinez, M.; Maruyama, R. H.; Moggi, N.; Morganti, S.; Napolitano, T.; Newman, S.; Nisi, S.; Nones, C.; Norman, E. B.; Nucciotti, A.; Orio, F.; Orlandi, D.; Ouellet, J. L.; Pallavicini, M.; Palmieri, V.; Pattavina, L.; Pavan, M.; Pedretti, M.; Pessina, G.; Pirro, S.; Previtali, E.; Rampazzo, V.; Rimondi, F.; Rosenfeld, C.; Rusconi, C.; Salvioni, C.; Sangiorgio, S.; Schaeffer, D.; Scielzo, N. D.; Sisti, M.; Smith, A. R.; Stivanello, F.; Taffarello, L.; Terenziani, G.; Tian, W. D.; Tomei, C.; Trentalange, S.; Ventura, G.; Vignati, M.; Wang, B. S.; Wang, H. W.; Whitten Jr., C. A.; Wise, T.; Woodcraft, A.; Xu, N.; Zanotti, L.; Zarra, C.; Zhu, B. X.; Zucchelli, S.

    2011-11-23

    In this paper, we study the sensitivity of CUORE, a bolometric double-beta decay experiment under construction at the Laboratori Nazionali del Gran Sasso in Italy. Two approaches to the computation of experimental sensitivity are discussed and compared, and the formulas and parameters used in the sensitivity estimates are provided. Assuming a background rate of 10{sup -2} cts/(keV kg y), we find that, after 5 years of live time, CUORE will have a 1 {sigma} sensitivity to the neutrinoless double-beta decay half-life of {caret T{sup 0{nu}}{sub 1/2}}(1{sigma} ) = 1.6x 10{sup 26} y and thus a potential to probe the effective Majorana neutrino mass down to 41-95 meV; the sensitivity at 1.64{sigma} , which corresponds to 90% C.L., will be {caret T{sup 0{nu}}{sub 1/2}(1.64{sigma} }) = 9.5x10{sup 25} y. This range is compared with the claim of observation of neutrinoless double-beta decay in {sup 76}Ge and the preferred range in the neutrino mass parameter space from oscillation results.

  14. CdWO4 bolometers for Double Beta Decay search

    CERN Document Server

    Gironi, L; Capelli, S; Cremonesi, O; Pavan, M; Pessina, G; Pirro, S

    2008-01-01

    In the field of Double Beta Decay (DBD) searches the possibility to have high resolution detectors in which background can be discriminated is very appealing. This very interesting possibility can be largely fulfilled in the case of a scintillating bolometer containing a Double Beta Decay emitter whose transition energy exceeds the one of the natural gamma line of 208Tl. We present the latest results obtained in the development of such a kind of scintillating bolometer. For the first time an array of five CdWO4 (116Cd has a Double Beta Decay transition energy of 2805 keV) crystals is tested. The array consists of a plane of four 3x3x3 cm3 crystals and a second plane consisting of a single 3x3x6 cm3 crystal. This setup is mounted in hall C of the National Laboratory of Gran Sasso inside a lead shielding in order to reduce as far as possible the environmental background. The aim of this test is to demonstrate the technical feasibility of this technique through an array of detectors and perform a long background...

  15. The MAJORANA Neutrinoless Double-Beta Decay Experiment

    International Nuclear Information System (INIS)

    Majorana collaboration paper for the IEEE Nuclear Science Symposium held in Dresden, Germany. It includes many authors from 17 institutions. Neutrinoless double-beta decay searches play a major role in determining the nature of neutrinos, the existence of a lepton violating process, and the effective Majorana neutrino mass. The MAJORANA Collaboration proposes to assemble an array of HPGe detectors to search for neutrinoless double-beta decay in 76Ge. Our proposed method uses the well-established technique of searching for neutrinoless double-beta decay in high purity Ge-diode radiation detectors that play both roles of source and detector. The technique is augmented with recent improvements in signal processing and detector design, and advances in controlling intrinsic and external backgrounds. Initially, MAJORANA aims to construct a prototype module containing 60 kg of Ge detectors to demonstrate the potential of a future 1-tonne experiment. The design and potential reach of this prototype Demonstrator module will be presented. This paper will also discuss detector optimization and low-background requirements, such as material purity, background rejection, and identification of rare backgrounds required to reach the sensitivity goals of the MAJORANA experiment.

  16. Total absorption study of beta decays relevant for nuclear applications

    International Nuclear Information System (INIS)

    In this contribution we will present an overview of recent studies of the beta decay of nuclei relevant for the calculation of the decay heat in nuclear reactors as a continuation of the work presented in (1). The measurements are performed using the best available technique to detect the beta feeding probability, the total absorption technique (TAS). In our studies we have combined the TAS technique with the use of a Penning Trap (JYFLTRAP, Univ. of Jyvaeskylae) as a high-resolution isobaric separator in order to guarantee high purity of the sources. A brief summary of the latest results of the measurements using a new segmented total absorption spectrometer, the faced challenges depending of the particular nuclei as well as new developments of the techniques of analysis will be discussed. The impact of the measurements on summation calculations of the decay heat in reactors, and in possible non-proliferation applications will be addressed. Future plans and the development of a new modular TAS detector (DTAS) for the DEcay SPECtroscopy (DESPCE) experiment at FAIR will also presented. (author)

  17. Search for neutrinoless double beta decay in 124Sn

    Directory of Open Access Journals (Sweden)

    Nanal Vandana

    2014-03-01

    Full Text Available The mass and nature of neutrinos play an important role in theories beyond the standard model. The nuclear β decay and double beta decay can provide the information on absolute effective mass of the neutrinos, which would represent a major advance in our understanding of particle physics. At present, neutrinoless double beta decay (0νββ is perhaps the only experiment that can tell us whether the neutrino is a Dirac or a Majorana particle. Given the significance of the 0νββ, there is a widespread interest for these rare event studies employing a variety of novel techniques. An essential criterion for detector design is the high energy resolution for a precision measurement of the sum energy of two electrons emitted in 0νββ decay. The low temperature bolometric detectors are ideally suited for this purpose. In India, efforts have been initiated to search for 0νββ in 124Sn at the upcoming underground facility of India based Neutrino Observatory (INO. A custom built cryogen free dilution refrigerator has been installed at TIFR, Mumbai for the development of Sn prototype bolometer. A base temperature of 10 mK has been achieved in this setup. This paper gives a brief description of efforts towards Sn bolometer development.

  18. An experimental investigation of double beta decay of 100Mo

    International Nuclear Information System (INIS)

    New limits on half-lives for several double beta decay modes of 100Mo were obtained with a novel experimental system which included thin source films interleaved with a coaxial array of windowless silicon detectors. Segmentation and timing information allowed backgrounds originating in the films to be studied in some detail. Dummy films containing 96Mo were used to assess remaining backgrounds. With 0.1 mole years of 100Mo data collected, the lower half-life limits at 90% confidence were 2.7 /times/ 1018 years for decay via the two-neutrino mode, 5.2 /times/1019 years for decay with the emission of a Majoron, and 1.6 /times/ 1020 years and 2.2 /times/ 1021 years for neutrinoless 0+ → 2+ and 0+ → 0+ transitions, respectively. 50 refs., 38 figs., 11 tabs

  19. Measurement of the η->π+π-e+e- decay branching ratio

    International Nuclear Information System (INIS)

    The reaction pd->He3η at threshold was used to provide a clean source of η mesons for decay studies with the WASA detector at CELSIUS. The branching ratio of the decay η->π+π-e+e- is measured to be (4.3+/-1.3+/-0.4)x10-4

  20. Puzzle of W Leptonic Decay Branching Fractions and Gauge Model of Generation Nonuniversality

    OpenAIRE

    Li, Xiao-Yuan; Ma, Ernest

    2005-01-01

    Lepton generation universality holds very well in Z decays, but appears to be violated in recent LEP data of W leptonic decay branching fractions. If this trend persists, a consistent and natural explanation is a model of generation nonuniversality, based on the gauge group SU(2)_L X U(1)_R X U(1)_{B-L}.

  1. Search for beta plus/EC double beta decay of 120Te

    CERN Document Server

    Andreotti, E; Avignone, F T; Balata, M; Bandac, I; Barucci, M; Beeman, J W; Bellini, F; Brofferio, C; Bryant, A; Bucci, C; Canonica, L; Capelli, S; Carbone, L; Carrettoni, M; Clemenza, M; Cremonesi, O; Creswick, R J; Di Domizio, S; Dolinski, M J; Ejzak, L; Faccini, R; Farach, H A; Ferri, E; Fiorini, E; Foggetta, L; Giachero, A; Gironi, L; Giuliani, A; Gorla, P; Guardincerri, E; Haller, T D Gutierrez E E; Kazkaz, K; Kraft, S; Kogler, L; Maiano, C; Maruyama, R H; Martinez, C; Martinez, M; Mizouni, L; Newman, S; Nisi, S; Nones, C; Norman, E B; Nucciotti, A; Orio, F; Pallavicini, M; Palmieri, V; Pattavina, L; Pavan, M; Pedretti, M; Pessina, G; Pirro, S; Previtali, E; Risegari, L; Rosenfeld, C; Rusconi, C; Salvioni, C; Sangiorgio, S; Schaeffer, D; Scielzo, N D; Sisti, M; Smith, A R; Tomei, C; Ventura, G; Vignati, M

    2010-01-01

    We present a search for beta plus/EC double beta decay of 120Te performed with the CUORICINO experiment, an array of TeO2 cryogenic bolometers. After collecting 0.0573 kg y of 120Te, we see no evidence of a signal and therefore set the following limits on the half-life: T1/2 (0nu) > 1.9 10^{21} y at 90% C.L. for the 0 neutrino mode and T1/2 (2nu) > 7.6 10^{19} y at 90% C.L. for the two neutrino mode. These results improve the existing limits by almost three orders of magnitude (four in the case of 0 neutrino mode). Moreover the limit on zero neutrino beta plus/EC represents the most stringent half-life limit ever achieved for this decay mode for any isotope.

  2. Nuclear double beta decay and the evidence for lepton number non-conservation

    International Nuclear Information System (INIS)

    The reported ratio of double beta decay of the isotopes 128Te and 130Te measured by geochemical techniques, coupled with an assumed equality of the nuclear matrix elements, would indicate the existence of a neutrinoless branch indicative of lepton number violation. A large-scale shell model calculation of the nuclear matrix elements was performed; they were found to be approximately equal. However, the absolute rates calculated for the normal, two-neutrino branch alone are 49 times faster than experiment for 128Te and 156 times faster than experiment for 130Te. In a similar vein, a rate that is 18 times faster than the geochemical result is calculated for the transition 82Se → 82Kr; however, that calculation is in essential agreement with a recent counting experiment. It is argued that, until these large discrepancies are resolved, one cannot say anything definitive about lepton number violation, although the possibility that the ratio of rates is indicating a positive signal remains. It is also noted that, for the case of 76Ge → 76Se, a pure Majorana mass of 35 eV is ruled out by Fiorini's limit on neutrinoless double beta decay. 3 tables

  3. A Novel Approach to β-delayed Neutron Spectroscopy Using the Beta-decay Paul Trap

    International Nuclear Information System (INIS)

    A new approach to β-delayed neutron spectroscopy has been demonstrated that circumvents the many limitations associated with neutron detection by instead inferring the decay branching ratios and energy spectra of the emitted neutrons by studying the nuclear recoil. Using the Beta-decay Paul Trap, fission-product ions were trapped and confined to within a 1-mm3 volume under vacuum using only electric fields. Results from recent measurements of 137I+ and plans for development of a dedicated ion trap for future experiments using the intense fission fragment beams from the Californium Rare Isotope Breeder Upgrade (CARIBU) facility at Argonne National Laboratory are summarized. The improved nuclear data that can be collected is needed in many fields of basic and applied science such as nuclear energy, nuclear astrophysics, and stockpile stewardship

  4. Assessment of molecular effects on neutrino mass measurements from tritium beta decay

    CERN Document Server

    Bodine, L I; Robertson, R G H

    2015-01-01

    The beta decay of molecular tritium currently provides the highest sensitivity in laboratory-based neutrino mass measurements. The upcoming Karlsruhe Tritium Neutrino (KATRIN) experiment will improve the sensitivity to 0.2 eV, making a percent-level quantitative understanding of molecular effects essential. The modern theoretical calculations available for neutrino-mass experiments agree with spectroscopic data. Moreover, when neutrino-mass experiments performed in the 1980s with gaseous tritium are re-evaluated using these modern calculations, the extracted neutrino mass-squared values are consistent with zero instead of being significantly negative. On the other hand, the calculated molecular final-state branching ratios are in tension with dissociation experiments performed in the 1950s. We re-examine the theory of the final-state spectrum of molecular tritium decay and its effect on the determination of the neutrino mass, with an emphasis on the role of the vibrational- and rotational-state distribution i...

  5. Branching ratios of B→DsK decays in perturbative QCD approach

    International Nuclear Information System (INIS)

    The rare decays B0→Ds-K+ and B+→Ds+K0 can occur only via annihilation type diagrams in the standard model. We calculate these decays in the perturbative QCD approach. We found that the calculated branching ratio of B0→Ds-K+ agreed with the data which had been observed in the KEK and SLAC B factories. The decay B+→Ds+K0 has a very small branching ratio at O(10-8), due to the suppression from the CKM matrix elements vertical stroke Vub*Vcd vertical stroke. (orig.)

  6. Neutrinoless double beta decay and heavy sterile neutrinos

    International Nuclear Information System (INIS)

    The experimental rate of neutrinoless double beta decay can be saturated by the exchange of virtual sterile neutrinos, that mix with the ordinary neutrinos and are heavier than 200 MeV. Interestingly, this hypothesis is subject only to marginal experimental constraints, because of the new nuclear matrix elements. This possibility is analyzed in the context of the Type I seesaw model, performing also exploratory investigations of the implications for heavy neutrino mass spectra, rare decays of mesons as well as neutrino-decay search, LHC, and lepton flavor violation. The heavy sterile neutrinos can saturate the rate only when their masses are below some 10 TeV, but in this case, the suppression of the light-neutrino masses has to be more than the ratio of the electroweak scale and the heavy-neutrino scale; i.e., more suppressed than the naive seesaw expectation. We classify the cases when this condition holds true in the minimal version of the seesaw model, showing its compatibility (1) with neutrinoless double beta rate being dominated by heavy neutrinos and (2) with any light neutrino mass spectra. The absence of excessive fine-tunings and the radiative stability of light neutrino mass matrices, together with a saturating sterile neutrino contribution, imply an upper bound on the heavy neutrino masses of about 10 GeV. We extend our analysis to the Extended seesaw scenario, where the light and the heavy sterile neutrino contributions are completely decoupled, allowing the sterile neutrinos to saturate the present experimental bound on neutrinoless double beta decay. In the models analyzed, the rate of this process is not strictly connected with the values of the light neutrino masses, and a fast transition rate is compatible with neutrinos lighter than 100 meV.

  7. The low background spectrometer TGV II for double beta decay measurements

    Energy Technology Data Exchange (ETDEWEB)

    Benes, P. [Institute of Experimental and Applied Physics, CTU in Prague, Horska 3a/22, 128 00 Prague (Czech Republic); Cermak, P. [Institute of Experimental and Applied Physics, CTU in Prague, Horska 3a/22, 128 00 Prague (Czech Republic)]. E-mail: pavel.cermak@utef.cvut.cz; Gusev, K.N. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Klimenko, A.A. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Kovalenko, V.E. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Kovalik, A. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Nuclear Physics Institute of the CAS, 25263 Rez near Prague (Czech Republic); Rukhadze, N.I. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Salamatin, A.V. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Simkovic, F. [Comenius University in Bratislava, SK-842 15 Bratislava (Slovakia); Stekl, I. [Institute of Experimental and Applied Physics, CTU in Prague, Horska 3a/22, 128 00 Prague (Czech Republic); Timkin, V.V. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Vylov, Ts. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation)

    2006-12-21

    The low-background multi-HPGe spectrometer TGVII installed in the Modane Underground Laboratory (France) is described in detail and the results of the background measurements are reported. The spectrometer is focused on the double beta decay measurements with two isotopes-{sup 106}Cd (2{nu}EC/EC mode) and {sup 48}Ca ({beta}{beta} mode). A basic summary of the physics of {beta}{beta} decay (especially EC/EC mode) is also given.

  8. Precision measurement of the radiative $\\beta$ decay of the free neutron

    CERN Document Server

    Bales, M J; Bass, C D; Beise, E J; Breuer, H; Byrne, J; Chupp, T E; Coakley, K J; Cooper, R L; Dewey, M S; Gardner, S; Gentile, T R; He, D; Mumm, H P; Nico, J S; O'Neill, B; Thompson, A K; Wietfeldt, F E

    2016-01-01

    The Standard Model predicts that, in addition to a proton, an electron, and an antineutrino, a continuous spectrum of photons is emitted in the $\\beta$ decay of the free neutron. We report on the RDK II experiment which measured the photon spectrum using two different detector arrays. An annular array of bismuth germanium oxide scintillators detected photons from 14~keV to 782~keV. The spectral shape was consistent with theory, and we determined a branching ratio of 0.00335 $\\pm$ 0.00005 [stat] $\\pm$ 0.00015 [syst]. A second detector array of large area avalanche photodiodes directly detected photons from 0.4~keV to 14~keV. For this array, the spectral shape was consistent with theory, and the branching ratio was determined to be 0.00582 $\\pm$ 0.00023 [stat] $\\pm$ 0.00062 [syst]. We report the first precision test of the shape of the photon energy spectrum from neutron radiative decay and a substantially improved determination of the branching ratio over a broad range of photon energies.

  9. Measurements of Branching Fractions and CP Asymmetries and Studies of Angular Distributions for B to phi phi K Decays

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-08-15

    We present branching fraction and CP asymmetry measurements as well as angular studies of B {yields} {phi}{phi}K decays using 464 x 10{sup 6} B{bar B} events collected by the BABAR experiment. The branching fractions are measured in the {phi}{phi} invariant mass range below the {eta}{sub c} resonance (m{sub {phi}{phi}} < 2.85 GeV). We find {Beta}(B{sup +} {yields} {phi}{phi}K{sup +}) = (5.6 {+-} 0.5 {+-} 0.3) x 10{sup -6} and {Beta}(B{sup 0} {yields} {phi}{phi}K{sup 0}) = (4.5 {+-} 0.8 {+-} 0.3) x 10{sup -6}, where the first uncertaintiy is statistical and the second systematic. The measured direct CP asymmetries for the B{sup {+-}} decays are A{sub CP} = -0.10 {+-} 0.08 {+-} 0.02 below the {eta}{sub c} threshold (m{sub {phi}{phi}} < 2.85 GeV) and A{sub CP} = 0.09 {+-} 0.10 {+-} 0.02 in the {eta}{sub c} resonance region (m{sub {phi}{phi}} in [2.94,3.02] GeV). Angular distributions are consistent with J{sub P} = 0{sup -} in the {eta}{sub c} resonance region and favor J{sup P} = 0{sup +} below the {eta}{sub c} resonance.

  10. Systematic study of the single-state dominance in 2 nu beta beta decay transitions

    CERN Document Server

    Civitarese, O

    1999-01-01

    The single-state-dominance hypothesis (SSDH) states that the decay rates of the two-neutrino double-beta decay are governed by a virtual two-step transition connecting the initial and final ground states through the first 1 sup + state, 1 sup + sub 1 , of the intermediate odd-odd nucleus, for those odd-odd nuclei where the 1 sup + sub 1 state is the ground state. To investigate the validity of the SSDH we have performed a systematical theoretical analysis of all known double-beta-decay transitions where the SSDH conditions are fulfilled. The calculations are based on the quasiparticle randon-phase approximation (QRPA) and the results have been obtained by using realistic single-particle bases and realistic interactions. We have studied the double beta sup - decays of sup 1 sup 0 sup 0 Mo, sup 1 sup 1 sup 0 Pd, sup 1 sup 1 sup 4 Cd, sup 1 sup 1 sup 6 Cd and sup 1 sup 2 sup 8 Te and the double electron-capture transitions in sup 1 sup 0 sup 6 Cd and sup 1 sup 3 sup 6 Ce. The analysis shows that the SSDH is real...

  11. The background in the neutrinoless double beta decay experiment GERDA

    CERN Document Server

    Agostini, M; Andreotti, E; Bakalyarov, A M; Balata, M; Barabanov, I; Heider, M Barnabe; Barros, N; Baudis, L; Bauer, C; Becerici-Schmidt, N; Bellotti, E; Belogurov, S; Belyaev, S T; Benato, G; Bettini, A; Bezrukov, L; Bode, T; Brudanin, V; Brugnera, R; Budjas, D; Caldwell, A; Cattadori, C; Chernogorov, A; Cossavella, F; Demidova, E V; Domula, A; Egorov, V; Falkenstein, R; Ferella, A; Freund, K; Frodyma, N; Gangapshev, A; Garfagnini, A; Gotti, C; Grabmayr, P; Gurentsov, V; Gusev, K; Guthikonda, K K; Hampel, W; Hegai, A; Heisel, M; Hemmer, S; Heusser, G; Hofmann, W; Hult, M; Inzhechik, L V; Ioannucci, L; Csathy, J Janicsko; Jochum, J; Junker, M; Kihm, T; Kirpichnikov, I V; Kirsch, A; Klimenko, A; Knoepfle, K T; Kochetov, O; Kornoukhov, V N; Kuzminov, V V; Laubenstein, M; Lazzaro, A; Lebedev, V I; Lehnert, B; Liao, H Y; Lindner, M; Lippi, I; Liu, X; Lubashevskiy, A; Lubsandorzhiev, B; Lutter, G; Macolino, C; Machado, A A; Majorovits, B; Maneschg, W; Nemchenok, I; Nisi, S; O'Shaughnessy, C; Palioselitis, D; Pandola, L; Pelczar, K; Pessina, G; Pullia, A; Riboldi, S; Sada, C; Salathe, M; Schmitt, C; Schreiner, J; Schulz, O; Schwingenheuer, B; Schoenert, S; Shevchik, E; Shirchenko, M; Simgen, H; Smolnikov, A; Stanco, L; Strecker, H; Tarka, M; Ur, C A; Vasenko, A A; Volynets, O; von Sturm, K; Wagner, V; Walter, M; Wegmann, A; Wester, T; Wojcik, M; Yanovich, E; Zavarise, P; Zhitnikov, I; Zhukov, S V; Zinatulina, D; Zuber, K; Zuzel, G

    2014-01-01

    The GERmanium Detector Array (GERDA) experiment at the Gran Sasso underground laboratory (LNGS) of INFN is searching for neutrinoless double beta decay of 76Ge. The signature of the signal is a monoenergetic peak at 2039 keV, the Q-value of the decay, Q_bb. To avoid bias in the signal search, the present analysis does not consider all those events, that fall in a 40 keV wide region centered around Q_bb. The main parameters needed for the neutrinoless double beta decay analysis are described. A background model was developed to describe the observed energy spectrum. The model contains several contributions, that are expected on the basis of material screening or that are established by the observation of characteristic structures in the energy spectrum. The model predicts a flat energy spectrum for the blinding window around Q_bb with a background index ranging from 17.6 to 23.8*10^{-3} counts/(keV kg yr). A part of the data not considered before has been used to test if the predictions of the background model...

  12. $\\beta$ - decay asymmetry in mirror nuclei: A = 9

    CERN Multimedia

    Axelsson, L E; Smedberg, M

    2002-01-01

    Investigations of light nuclei close to the drip lines have revealed new and intriguing features of the nuclear structure. The occurrence of halo structures in loosely bound systems has had a great impact on the nuclear physics research in the last years. As intriguing but not yet solved is the nature of transitions with very large $\\beta$ - strength. \\\\ \\\\We report here on the investigation of this latter feature by an accurate measurement of the $\\beta$ - decay asymmetry between the mirror nuclei in the A=9 mass chain.\\\\ \\\\The possible asymmetry for the decay to the states around 12 MeV is interesting not only due to the fact that the individual B$_{GT}$ values are large (with large overlap in wave-functions, an unambiguous interpretation is much easier made), but also due to the special role played by this transition for the $^{9}$Li decay. It seems to belong to a class of high-B$_{GT}$ transitions observed at the neutron drip line and has been suggested to be due either to a lowering of the giant Gamow-Te...

  13. The rp-process and new measurements of $\\beta$-delayed proton decay of light Ag and Cd isotopes

    CERN Document Server

    Raimann, G; Boyd, R N; Cano-Ott, D; Collatz, R; Guglielmetti, A; Hellström, M; Hencheck, M; Hu, Z; Janas, Z; Karny, M; Kirchner, R; Morford, L J; Morrissey, D J; Roeckl, E; Schmidt, K; Szerypo, J; Weber, A

    1996-01-01

    Recent network calculations suggest that a high temperature rp-process could explain the abundances of light Mo and Ru isotopes, which have long challenged models of p-process nuclide production. Important ingredients to network calculations involving unstable nuclei near and at the proton drip line are \\beta-halflives and decay modes, i.e., whether or not \\beta-delayed proton decay takes place. Of particular importance to these network calculation are the proton-rich isotopes ^{96}Ag, ^{98}Ag, ^{96}Cd and ^{98}Cd. We report on recent measurements of \\beta-delayed proton branching ratios for ^{96}Ag, ^{98}Ag, and ^{98}Cd at the on-line mass separator at GSI.

  14. Beta-decay of the N=Z nucleus 72Kr

    International Nuclear Information System (INIS)

    The beta-decay of the N = Z, even-even nucleus 72Kr has been studied at the ISOLDE PSB facility at CERN. Measurements of βγ and βγγ coincidences have enriched the decay scheme of the daughter nucleus 72Br with 27 new low spin levels. A more precise half-life of T1/2 = 17.1(2) s has been determined. Strong feeding to the 72Br ground state is established yielding an unambiguous Jπ = 1+ assignment for this state. Candidates for the 72Br g.s. wave function are discussed in the framework of a self-consistent deformed mean-field calculation with SG2 Skyrme force and pairing correlations. A search for beta-delayed particle emission was made and an upper limit of 10-6 for this decay branch obtained. The cumulated experimental level density of 1+ states has been fitted with the constant temperature formula. The comparison indicates that most likely all 1+ levels up to 1.2 MeV have been observed in this investigation. The corresponding nearest-neighbour level spacing does not follow a Poisson distribution. The Gamow-Teller strength distribution is compared, in terms of nuclear deformation, with different calculations made in the framework of the quasiparticle random phase approximation. (orig.)

  15. Competition of $\\beta$-delayed protons and $\\beta$-delayed $\\gamma$ rays in $^{56}$Zn and the exotic $\\beta$-delayed $\\gamma$-proton decay

    CERN Document Server

    Orrigo, S E A; Fujita, Y; Blank, B; Gelletly, W; Agramunt, J; Algora, A; Ascher, P; Bilgier, B; Cáceres, L; Cakirli, R B; Fujita, H; Ganioglu, E; Gerbaux, M; Giovinazzo, J; Grévy, S; Kamalou, O; Kozer, H C; Kucuk, L; Kurtukian-Nieto, T; Molina, F; Popescu, L; Rogers, A M; Susoy, G; Stodel, C; Suzuki, T; Tamii, A; Thomas, J C

    2016-01-01

    Remarkable results have been published recently on the $\\beta$ decay of $^{56}$Zn. In particular, the rare and exotic $\\beta$-delayed $\\gamma$-proton emission has been detected for the first time in the $fp$ shell. Here we focus the discussion on this exotic decay mode and on the observed competition between $\\beta$-delayed protons and $\\beta$-delayed $\\gamma$ rays from the Isobaric Analogue State.

  16. The MAJORANA DEMONSTRATOR Neutrinoless Double-Beta Decay Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Abgrall, N.; Aguayo, Estanislao; Avignone, Frank T.; Barabash, Alexander S.; Bertrand, F.; Boswell, M.; Brudanin, V.; Busch, Matthew; Caldwell, A. S.; Chan, Yuen-Dat; Christofferson, Cabot-Ann; Combs, Dustin C.; Detwiler, Jason A.; Doe, Peter J.; Efremenko, Yuri; Egorov, Viatcheslav; Ejiri, H.; Elliott, S. R.; Esterline, James H.; Fast, James E.; Finnerty, P.; Fraenkle, Florian; Galindo-Uribarri, A.; Giovanetti, G. K.; Goett, J.; Green, M.; Gruszko, J.; Guiseppe, Vincente; Gusev, K.; Hallin, A. L.; Hazama, R.; Hegai, A.; Henning, Reyco; Hoppe, Eric W.; Howard, Stanley; Howe, M. A.; Keeter, K.; Kidd, M. F.; Knecht, A.; Kochetov, Oleg; Konovalov, S.; Kouzes, Richard T.; Laferriere, Brian D.; Leon, Jonathan D.; Leviner, L.; Loach, J. C.; Luke, P.; MacMullin, S.; Martin, R. D.; Mertens, S.; Mizouni, Leila; Nomachi, Masaharu; Orrell, John L.; O' Shaughnessy, C.; Overman, Nicole R.; Phillips, David; Poon, Alan; Pushkin, K.; Radford, D. C.; Rielage, Keith; Robertson, R. G. H.; Ronquest, M. C.; Schubert, Alexis G.; Shanks, B.; Shima, T.; Shirchenko, M.; Snavely, Kyle J.; Snyder, N.; Steele, David; Strain, J.; Suriano, Anne-Marie; Thompson, J.; Timkin, V.; Tornow, Werner; Varner, R. L.; Vasilyev, Sergey; Vetter, Kai; Vorren, Kris R.; White, Brandon R.; Wilkerson, J. F.; Williams, T.; Xu, W.; Yakushev, E.; Young, A.; Yu, Chang-Hong; Yumatov, Vladimir

    2014-06-01

    The MAJORANA DEMONSTRATOR will search for the neutrinoless double-beta (ββ(0ν)) decay of the isotope 76Ge with a mixed array of enriched and natural germanium detectors. The observation of this rare decay would indicate that the neutrino is its own antiparticle, demonstrate that lepton number is not conserved, and provide information on the absolute mass scale of the neutrino. The DEMONSTRATOR is being assembled at the 4850-foot level of the Sanford Underground Research Facility in Lead, South Dakota. The array will be situated in a low-background environment and surrounded by passive and active shielding. Here we describe the science goals of the DEMONSTRATOR and the details of its design.

  17. The MAJORANA DEMONSTRATOR Neutrinoless Double-Beta Decay Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Abgrall, N.; Aguayo, Estanislao; Avignone, III, F. T.; Barabash, A.; Bertrand, F.; Boswell, M.; Brudanin, V.; Busch, Matthew; Caldwell, A. S.; Chan, Yuen-Dat; Christofferson, Cabot-Ann; Combs, Dustin C.; Detwiler, Jason A.; Doe, Peter J.; Efremenko, Yuri; Egorov, Viatcheslav; Ejiri, H.; Elliott, S. R.; Esterline, James H.; Fast, James E.; Finnerty, P.; Fraenkle, Florian; Galindo-Uribarri, A.; Giovanetti, G. K.; Goett, J.; Green, M.; Gruszko, J.; Guiseppe, Vincente; Gusev, K.; Hallin, A. L.; Hazama, R.; Hegai, A.; Henning, Reyco; Hoppe, Eric W.; Howard, Stanley; Howe, M. A.; Keeter, K.; Kidd, M. F.; Knecht, A.; Kochetov, Oleg; Konovalov, S.; Kouzes, Richard T.; Laferriere, Brian D.; Leon, Jonathan D.; Leviner, L.; Loach, J. C.; Luke, P.; MacMullin, S.; Martin, R. D.; Mertens, S.; Mizouni, Leila; Nomachi, Masaharu; Orrell, John L.; O' Shaughnessy, Mark D.; Overman, Nicole R.; Phillips, David; Poon, Alan; Pushkin, K.; Radford, D. C.; Rielage, Keith; Robertson, R. G. H.; Ronquest, M. C.; Schubert, Alexis G.; Shanks, B.; Shima, T.; Shirchenko, M.; Snavely, Kyle J.; Snyder, N.; Steele, David; Strain, J.; Suriano, Anne-Marie; Thompson, J.; Timkin, V.; Tornow, Werner; Varner, R. L.; Vasilyev, Sergey; Vetter, Kai; Vorren, Kris R.; White, Brandon R.; Wilkerson, J. F.; Williams, T.; Xu, W.; Yakushev, E.; Young, A.; Yu, Chang-Hong; Yumatov, Vladimir

    2014-01-01

    The Majorana Demonstrator will search for the neutrinoless double-beta (ββ (0ν)) decay of the isotope 76Ge with a mixed array of enriched and natural germanium detectors. The observation of this rare decay would indicate that the neutrino is its own antiparticle, demonstrate that lepton number is not conserved, and provide information on the absolute mass scale of the neutrino. TheDemonstrator is being assembled at the 4850-foot level of the SanfordUnderground Research Facility in Lead, SouthDakota. The array will be situated in a low-background environment and surrounded by passive and active shielding. Here we describe the science goals of the Demonstrator and the details of its design.

  18. Ground state occupation probabilities of neutrinoless double beta decay candidates

    Science.gov (United States)

    Kotila, Jenni; Barea, Jose

    2015-10-01

    A better understanding of nuclear structure can offer important constraints on the calculation of 0 νββ nuclear matrix elements. A simple way to consider differences between initial and final states of neutrinoless double beta decay candidates is to look at the ground state occupation probabilities of initial and final nuclei. As is well known, microscopic interacting boson model (IBM-2) has found to be very useful in the description of detailed aspects of nuclear structure. In this talk I will present results for ground state occupation probabilities obtained using IBM-2 for several interesting candidates of 0 νββ -decay. Comparison with recent experimental results is also made. This work was supported Academy of Finland (Project 266437) and Chilean Ministry of Education (Fondecyt Grant No. 1150564),

  19. Search of Neutrinoless Double Beta Decay with the GERDA Experiment

    CERN Document Server

    Benato, Giovanni

    2015-01-01

    The Gerda experiment designed to search for the neutrinoless double beta decay in 76Ge has successfully completed the first data collection. No signal excess is found, and a lower limit on the half life of the process is set, with T1/2 > 2.1x10^25 yr (90% CL). After a review of the experimental setup and of the main Phase I results, the hardware upgrade for Gerda Phase II is described, and the physics reach of the new data collection is reported.

  20. Neutrinoless Double Beta Decay in Heavy Deformed Nuclei

    OpenAIRE

    Hirsch, Jorge G.; Castaños, O.; Hess, P. O.

    1994-01-01

    The zero neutrino mode of the double beta decay in heavy deformed nuclei is investigated in the framework of the pseudo SU(3) model, which has provided an accurate description of collective nuclear structure and predicted half-lives for the two neutrino mode in good agreement with experiments. In the case of $^{238}U$ the calculated zero neutrino half-life is at least three orders of magnitude greater than the two neutrino one, giving strong support of the identification of the radiochemicall...

  1. Values of the phase space factors for double beta decay

    International Nuclear Information System (INIS)

    We report an up-date list of the experimentally most interesting phase space factors for double beta decay (DBD). The electron/positron wave functions are obtained by solving the Dirac equations with a Coulomb potential derived from a realistic proton density distribution in nucleus and with inclusion of the finite nuclear size (FNS) and electron screening (ES) effects. We build up new numerical routines which allow us a good control of the accuracy of calculations. We found several notable differences as compared with previous results reported in literature and possible sources of these discrepancies are discussed

  2. Neutrinoless Double Beta Decay and Lepton Flavor Violation

    OpenAIRE

    Cirigliano, V.; Kurylov, A.; Ramsey-Musolf, M. J.; Vogel, P.

    2004-01-01

    We point out that extensions of the standard model with low scale (~TeV) lepton number violation (LNV) generally lead to a pattern of lepton flavor violation (LFV) experimentally distinguishable from the one implied by models with grand unified theory scale LNV. As a consequence, muon LFV processes provide a powerful diagnostic tool to determine whether or not the effective neutrino mass can be deduced from the rate of neutrinoless double beta decay. We discuss the role of µ-->egamma and µ-->...

  3. LUCIFER: A new technique for Double Beta Decay

    OpenAIRE

    Ferroni, Fernando

    2011-01-01

    LUCIFER (Low-background Underground Cryogenic Installation For Elusive Rates) is a new project aiming to study the neutrinoless Double Beta Decay. It will be based on the technology of the scintillating bolometers. These devices shall have a great power in distinguishing signals from α’s and β/γ’s promising a background-free experiment, provided that the Q value of the candidate isotope is higher than the 208Tl line. The baseline candidate for LUCIFER is 82Se. Here the LUCIFER concept will be...

  4. The Majorana Ge-76 Double-Beta Decay Project

    CERN Document Server

    Aalseth, C E; Barabash, A S; Bowyer, T W; Brodzinski, R L; Brudanin, V B; Collar, J I; Doe, P J; Egorov, S; Elliott, S R; Farach, H A; Gaitskell, R J; Jordan, D; Kochetov, O I; Konovalov, S V; Kouzes, R T; Miley, H S; Pitts, W K; Reeves, J H; Robertson, R G H; Sandukovsky, V G; Smith, E; Stekhanov, V; Thompson, R C; Tornow, W; Umatov, V I; Warner, R A; Webb, J; Wilkerson, J F; Young, A

    2002-01-01

    The Majorana Experiment is a next-generation Ge-76 double-beta decay search. It will employ 500 kg of Ge, isotopically enriched to 86% in Ge-76, in the form of 200 detectors in a close-packed array for high granularity. Each crystal will be electronically segmented, with each region fitted with pulse-shape analysis electronics. A half-life sensitivity is predicted of 4.2e27 y or < 0.02-0.07 eV, depending on the nuclear matrix elements used to interpret the data.

  5. Impact of Neutrinoless Double Beta Decay on Models of Baryogenesis

    CERN Document Server

    Deppisch, Frank F; Huang, Wei-Chih

    2015-01-01

    Interactions that manifest themselves as lepton number violating processes at low energies in combination with sphaleron transitions typically erase any pre-existing baryon asymmetry of the Universe. We demonstrate in a model independent approach that the observation of neutrinoless double beta decay would impose a stringent constraint on mechanisms of high-scale baryogenesis, including leptogenesis scenarios. Further, we discuss the potential of the LHC to model independently exclude high-scale leptogenesis scenarios when observing lepton number violating processes. In combination with the observation of lepton flavor violating processes, we can further strengthen this argument, closing the loophole of asymmetries being stored in different lepton flavors.

  6. Measurement of Branching Fractions of B0 Decays to K1(1270)+ pi- and K1(1400)+ pi-

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-08-04

    We present a measurement of the branching fraction of neutral B meson decaying to final states containing a K1 meson, i.e. K{sub 1}(1270) and K{sub 1}(1400), and a charged pion. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 454 million B{bar B} pairs produced in e{sup +}e{sup -} annihilation. We measure the branching fraction {Beta}(B{sup 0} {yields} K{sub 1}{sup +}{pi}{sup -}) = (31.0 {+-} 2.7 {+-} 6.9) x 10{sup -6}, where the first error quoted is statistical and the second is systematic. In the framework of the K-matrix formalism used to describe these decays, we also set limits on the ratio of the production constants for the K{sub 1}(1270){sup +} and K{sub 1}(1400){sup +} mesons in B{sup 0} decays.

  7. Neutron beta decay studies at the Institut Laue-Langevin

    International Nuclear Information System (INIS)

    In the frame of the electroweak Standard Model of particle physics, neutron beta decay is described by only two parameters: the element Vud of the weak quark mixing matrix (CKM matrix) and the ratio λ=gA/gV of the weak coupling constants of the neutron. Experimentally, a larger number of neutron decay parameters are accessible. These are the lifetime and various correlation coefficients between the spins and momenta of the particles involved in neutron decay. Hence, the problem is strongly overdetermined, and many tests going beyond the Standard Model are possible. These comprise tests of the unitarity of the CKM matrix, tests for tensor and scalar admixtures, searches for right-handed currents within the frame of left-right symmetric models, as well as tests of time reversal symmetry. During the past years various groups working in this field have made considerable progress in neutron decay experimentation. In our presentation we shall give a survey on new experiments performed at the Institut Laue-Langevin, Grenoble, France, and on the results concerning the Standard Model

  8. Measurement of double-beta-decay--experiments TGV and NEMO

    International Nuclear Information System (INIS)

    A description of the aim and present status of the experiments NEMO and TGV are presented. The NEMO collaboration developed the detector NEMO-2 to investigate double-beta (ββ) decay of 100Mo, 116Cd, 82Se and 96Zr. The results obtained for the above mentioned isotopes are given. The new detector NEMO-3, which is approximately 20 times larger than NEMO-2, is under construction. The NEMO-3 detector should allow the study of 0νββ decays of 100Mo (or other isotopes) with half-life ∼1025 years, corresponding to neutrino masses of 0.1-0.3 eV. The TGV I collaboration has studied the ββ decay of 48Ca. The result T2νββ1/2=(4.2+3.3-1.3)x1019 years has been found. Experiment TGV II is devoted to measurement of the ββ decay (β+β+, β+/EC, EC/EC) of 106Cd, particularly the 2νEC/EC mode. (author)

  9. Theory of neutrinoless double-beta decay - a brief review

    International Nuclear Information System (INIS)

    Neutrinoless double-beta decay (0νββ-decay) is a unique probe for lepton number conservation and neutrino properties. This is a process with long and interesting history with important implications for particle physics and cosmology, but its observation is still elusive. The search for the 0νββ-decay represents the new frontiers of neutrino physics, allowing one to determine the Majorana nature of neutrinos and to fix the neutrino mass scale and possible CP-violation effects, which could explain the matter-antimatter asymmetry in the Universe. At present, a complete theory is missing and, thus, to motivate and guide the experiments, the mechanism mediated by light neutrinos is mostly considered. The subject of interest is an effective mass of Majorana neutrinos, which can be deduced from the measured half-life, once this process is definitely observed. The accuracy of the determination of this quantity is mainly determined by our knowledge of the nuclear matrix elements. There is a request to evaluate them with high precision, accuracy and reliability. Recently, there is an increased interest in the resonant neutrinoless double-electron capture, which may also establish the Majorana nature of neutrinos. This possibility is considered as alternative and complementary to searches for the 0νββ-decay

  10. Testing the importance of collective correlations in neutrinoless $\\beta\\beta$ decay

    CERN Document Server

    Menéndez, J; Engel, J; Martínez-Pinedo, G; Rodríguez, T R

    2016-01-01

    We investigate the extent to which theories of collective motion can capture the physics that determines the nuclear matrix elements governing neutrinoless double-beta decay. To that end we calculate the matrix elements for a series of isotopes in the full $pf$ shell, omitting no spin-orbit partners. With the inclusion of isoscalar pairing, a separable collective Hamiltonian that is derived from the shell model effective interaction reproduces the full shell-model matrix elements with good accuracy. A version of the generator coordinate method that includes the isoscalar pairing amplitude as a coordinate also reproduces the shell model results well, an encouraging result for theories of collective motion, which can include more single-particle orbitals than the shell model. We briefly examine heavier nuclei relevant for experimental double-beta decay searches, in which shell-model calculations with all spin-orbit partners are not feasible; our estimates suggest that isoscalar pairing also plays a significant ...

  11. Shell Model description of the {beta}{beta} decay of {sup 136}Xe

    Energy Technology Data Exchange (ETDEWEB)

    Caurier, E.; Nowacki, F. [IPHC, IN2P3-CNRS/Universite Louis Pasteur BP 28, F-67037 Strasbourg Cedex 2 (France); Poves, A., E-mail: alfredo.poves@uam.es [Departamento de Fisica Teorica, Universidad Autonoma de Madrid and Instituto de Fisica Teorica, UAM/CSIC, E-28049, Madrid (Spain)

    2012-05-01

    We study in this Letter the double beta decay of {sup 136}Xe with emission of two neutrinos which has been recently measured by the EXO-200 Collaboration. We use the same shell model framework, valence space, and effective interaction that we have already employed in our calculation of the nuclear matrix element (NME) of its neutrinoless double beta decay. Using the quenching factor of the Gamow-Teller operator which is needed to reproduce the very recent high resolution {sup 136}Xe ({sup 3}He, t) {sup 136}Cs data, we obtain a nuclear matrix element M{sup 2{nu}}=0.025 MeV{sup -1} compared with the experimental value M{sup 2{nu}}=0.019(2) MeV{sup -1}.

  12. Isospin-symmetry-hindered branch of 42Sc β-decay

    International Nuclear Information System (INIS)

    The branching fraction for the isospin-symmetry-hindered positron decay of 42Sc to 42Ca (1.837 MeV) was measured to be (6.3+-2.6)x105 by observation of delayed γ-rays. This branch alone corresponds to a reduction of the superallowed ground-state Fermi strength by (0.043+-0.018)%. The 42Sc sources were produced by the 42Ca(p,n)42Sc reaction at 7.7 MeV. The measured branching agrees with Coulomb-mixing calculations by Rappleyea and Kunz and by Towner, but is smaller than other calculations. This result is of interest in connection with the intercomparison of the superallowed 0+ → 0+ pure Fermi decays, which determine the effective vector coupling constant of nuclear β-decay. (Auth.)

  13. Double beta decay versus cosmology: Majorana CP phases and nuclear matrix elements

    CERN Document Server

    Deppisch, F; Suhonen, J; Deppisch, Frank; P\\"as, Heinrich; Suhonen, Jouni

    2004-01-01

    We discuss the relation between the absolute neutrino mass scale, the effective mass measured in neutrinoless double beta decay, and the Majorana CP phases. Emphasis is placed on estimating the upper bound on the nuclear matrix element entering calculations of the double beta decay half life. Consequently, one of the Majorana CP phases can be constrained when combining the claimed evidence for neutrinoless double beta decay with the neutrino mass bound from cosmology.

  14. On the exponential decay of Laplacian eigenfunctions in planar domains with branches

    OpenAIRE

    Nguyen, Binh T.; Delytsin, Andrey L.; Grebenkov, Denis S.

    2013-01-01

    We consider the eigenvalue problem for the Laplace operator in a planar domain which can be decomposed into a bounded domain of arbitrary shape and elongated \\branches" of variable cross-sectional pro?les. When the eigenvalue is smaller than a prescribed threshold, the corresponding eigenfunction decays exponentially along each branch. We prove this behavior for Robin boundary condition and illustrate some related results by numerically computed eigenfunctions.

  15. Bonner Prize Talk -- First Laboratory Observation of Double Beta Decay

    Science.gov (United States)

    Moe, Michael

    2013-04-01

    Although we are awash in neutrinos, we remain ignorant of some of their fundamental properties. We don't know their masses. We don't know whether ``anti-neutrinos'' are really distinct particles. Double beta (ββ) decay offers a handle on these questions if we can observe the energy spectrum of the two emitted electrons, and determine whether or not they share their energy with two neutrinos. Seeing neutrinoless (0ν) decay would solve some enduring puzzles. The power of the process to elucidate the neutrino was recognized in the 1930's, but ββ decay would be exceedingly rare and difficult to detect. Unsuccessful laboratory searches had been going on for 25 years when the UC Irvine group began its first experiment with a cloud chamber in 1972. After some background for the non-expert, and a snapshot of the theoretical and experimental milieu at the time, the talk will begin with the reasons for choosing a cloud chamber, and the taming of its balky and idiosyncratic behavior. The talk will end with the first definitive observation of two-neutrino (2ν)ββ decay of ^82Se in the vastly superior time projection chamber (TPC) in 1987. Discouragement through the tortuous 15-year interval was relieved by occasional victories. Some I will illustrate with revealing cloud-chamber photographs. We learned many things from this primitive device, and after seven years we isolated an apparent ββ decay signal. But the efficiency of the trigger was small, and difficult to pin down. Estimating 2.2%, we were way low. The resulting ``short'' ^82Se half-life of 1 x 10^19 years was suspect. New technology came to the rescue with the invention of the TPC. Experience with the cloud chamber guided our design of a TPC specifically for ββ decay. The TPC was built from scratch. Its long, steep learning curve was also punctuated with little triumphs. A memorable moment was the first turn-on of a portion of the chamber. So long ago, this all seems rather quaint, but through ample use of

  16. On the Proton Spectrum in Free Neutron beta-decay

    CERN Document Server

    Bunatian, G G

    2000-01-01

    We consider the calculations which are appropriate to acquire with a high precision, of ~1% or better, the general characteristics of weak interactions from the experiments on the free neutron beta-decay; the principle emphasis is placed on the phenomena associated with the recoil of protons. The part played by electromagnetic interactions in beta-decay is visualized, with special attention drawn to the influence of the gamma-radiation on the momentum distribution of the particles in the final state. The effect of electromagnetic interactions on the proton recoil spectrum is studied, in the light of the experiments which are carried out and planned for now. The results of the calculations, which are to be confronted with the experimental data, are presented upright in terms of the effective Lagrangian underlying the inquiry. Owing to electromagnetic interactions, the corrections to the energy distribution of protons prove to amount to the value of a few per cent. Nowadays, this is substantial to obtain with a...

  17. Present and future strategies for neutrinoless double beta decay searches

    Indian Academy of Sciences (India)

    C Brofferio

    2010-08-01

    The renewed interest shown in these days towards neutrinoless double beta decay, a lepton number violating process which can take place only if neutrinos are Majorana particles ($ = \\bar{}$) with a nonvanishing mass, is justified by the fact that the Majorana nature of neutrinos is expected in many theories beyond the Standard Model. We also now know, thanks to the neutrino oscillation experiments, that neutrinos are in fact massive, as expected in these theories and not requested in the Standard Model. Moreover, since neutrino oscillation experiments measure only the absolute value of the difference of the square of the neutrino masses, the discovery of neutrinoless double beta decay would help to disentangle questions that still remain unsolved: what is the absolute mass scale of the neutrinos and which mass hierarchy (normal, inverted or quasi-degenerate) is the correct one? The scope of this paper is not only to review the present results reached in the field by the different groups and technologies worldwide, but also to illustrate and comment on the (near and long-term) future strategies that experimentalists are trying to pursue to reach the needed sensitivity required to explore the inverted hierarchy neutrino mass scale.

  18. Study on branching ratios and direct CP asymmetries of D → PV decays

    International Nuclear Information System (INIS)

    We study the non-leptonic two-body decays of D mesons decaying into one pseudoscalar meson (P) and one vector meson (V) in the factorization-assisted topological-amplitude approach. In this approach, the decay amplitudes are factorized into two parts, the short-distance contribution (Wilson coefficients) and the long-distance contribution (hadronic matrix elements). We predict the branching ratios of D → PV decays using a global fit with the non-perturbative parameters. Our results agree well with the experimental data. We also predict the direct CP asymmetries by combining short-distance dynamics associated with penguin operators and long-distance hadronic matrix elements determined by branching ratios. The large asymmetries in D+ → π+ρ0 and Ds+ → K+φ may be measurable in the LHCb and future Belle II experiments. (author)

  19. Large-scale shell-model analysis of the neutrinoless $\\beta\\beta$ decay of $^{48}$Ca

    CERN Document Server

    Iwata, Y; Otsuka, T; Utsuno, Y; Menendez, J; Honma, M; Abe, T

    2016-01-01

    We present the nuclear matrix element for the neutrinoless double-beta decay of $^{48}$Ca based on large-scale shell-model calculations including two harmonic oscillator shells ($sd$ and $pf$ shells). The excitation spectra of $^{48}$Ca and $^{48}$Ti, and the two-neutrino double-beta decay of $^{48}$Ca are reproduced in good agreement to experiment. We find that the neutrinoless double-beta decay nuclear matrix element is enhanced by about 30\\% compared to $pf$-shell calculations. This reduces the decay lifetime by almost a factor of two. The matrix-element increase is mostly due to pairing correlations associated with cross-shell $sd$-$pf$ excitations. We also investigate possible implications for heavier neutrinoless double-beta decay candidates.

  20. An upper limit on the branching ratio for $\\tau$ decays into seven charged particles

    CERN Document Server

    Ackerstaff, K; Allison, J; Altekamp, N; Anderson, K J; Anderson, S; Arcelli, S; Asai, S; Axen, D A; Azuelos, Georges; Ball, A H; Barberio, E; Barlow, R J; Bartoldus, R; Batley, J Richard; Baumann, S; Bechtluft, J; Beeston, C; Behnke, T; Bell, A N; Bell, K W; Bella, G; Bentvelsen, Stanislaus Cornelius Maria; Berlich, P; Bethke, Siegfried; Biebel, O; Biguzzi, A; Bird, S D; Blobel, Volker; Bloodworth, Ian J; Bloomer, J E; Bobinski, M; Bock, P; Bonacorsi, D; Boutemeur, M; Bouwens, B T; Braibant, S; Brigliadori, L; Brown, R M; Burckhart, Helfried J; Burgard, C; Bürgin, R; Capiluppi, P; Carnegie, R K; Carter, A A; Carter, J R; Chang, C Y; Charlton, D G; Chrisman, D; Clarke, P E L; Cohen, I; Conboy, J E; Cooke, O C; Cuffiani, M; Dado, S; Dallapiccola, C; Dallavalle, G M; De Jong, S; del Pozo, L A; Desch, Klaus; Dixit, M S; do Couto e Silva, E; Doucet, M; Duchovni, E; Duckeck, G; Duerdoth, I P; Eatough, D; Edwards, J E G; Estabrooks, P G; Evans, H G; Evans, M; Fabbri, Franco Luigi; Fanti, M; Faust, A A; Fiedler, F; Fierro, M; Fischer, H M; Fleck, I; Folman, R; Fong, D G; Foucher, M; Fürtjes, A; Futyan, D I; Gagnon, P; Gary, J W; Gascon, J; Gascon-Shotkin, S M; Geddes, N I; Geich-Gimbel, C; Geralis, T; Giacomelli, G; Giacomelli, P; Giacomelli, R; Gibson, V; Gibson, W R; Gingrich, D M; Glenzinski, D A; Goldberg, J; Goodrick, M J; Gorn, W; Grandi, C; Gross, E; Grunhaus, Jacob; Gruwé, M; Hajdu, C; Hanson, G G; Hansroul, M; Hapke, M; Hargrove, C K; Hart, P A; Hartmann, C; Hauschild, M; Hawkes, C M; Hawkings, R; Hemingway, Richard J; Herndon, M; Herten, G; Heuer, R D; Hildreth, M D; Hill, J C; Hillier, S J; Hilse, T; Hobson, P R; Homer, R James; Honma, A K; Horváth, D; Howard, R; Hutchcroft, D E; Igo-Kemenes, P; Imrie, D C; Ingram, M R; Ishii, K; Jawahery, A; Jeffreys, P W; Jeremie, H; Jimack, Martin Paul; Joly, A; Jones, C R; Jones, G; Jones, M; Jost, U; Jovanovic, P; Junk, T R; Karlen, D A; Kartvelishvili, V G; Kawagoe, K; Kawamoto, T; Keeler, Richard K; Kellogg, R G; Kennedy, B W; Kirk, J; Klier, A; Kluth, S; Kobayashi, T; Kobel, M; Koetke, D S; Kokott, T P; Kolrep, M; Komamiya, S; Kress, T; Krieger, P; Von Krogh, J; Kyberd, P; Lafferty, G D; Lahmann, R; Lai, W P; Lanske, D; Lauber, J; Lautenschlager, S R; Layter, J G; Lazic, D; Lee, A M; Lefebvre, E; Lellouch, Daniel; Letts, J; Levinson, L; Lloyd, S L; Loebinger, F K; Long, G D; Losty, Michael J; Ludwig, J; Macchiolo, A; MacPherson, A L; Mannelli, M; Marcellini, S; Markus, C; Martin, A J; Martin, J P; Martínez, G; Mashimo, T; Mättig, P; McDonald, W J; McKenna, J A; McKigney, E A; McMahon, T J; McPherson, R A; Meijers, F; Menke, S; Merritt, F S; Mes, H; Meyer, J; Michelini, Aldo; Mikenberg, G; Miller, D J; Mincer, A; Mir, R; Mohr, W; Montanari, A; Mori, T; Morii, M; Müller, U; Nagai, K; Nakamura, I; Neal, H A; Nellen, B; Nisius, R; O'Neale, S W; Oakham, F G; Odorici, F; Ögren, H O; Oldershaw, N J; Oreglia, M J; Orito, S; Pálinkás, J; Pásztor, G; Pater, J R; Patrick, G N; Patt, J; Pearce, M J; Petzold, S; Pfeifenschneider, P; Pilcher, J E; Pinfold, James L; Plane, D E; Poffenberger, P R; Poli, B; Posthaus, A; Przysiezniak, H; Rees, D L; Rigby, D; Robertson, S; Robins, S A; Rodning, N L; Roney, J M; Rooke, A M; Ros, E; Rossi, A M; Rosvick, M; Routenburg, P; Rozen, Y; Runge, K; Runólfsson, O; Ruppel, U; Rust, D R; Rylko, R; Sachs, K; Saeki, T; Sarkisyan-Grinbaum, E; Sbarra, C; Schaile, A D; Schaile, O; Scharf, F; Scharff-Hansen, P; Schenk, P; Schieck, J; Schleper, P; Schmitt, B; Schmitt, S; Schöning, A; Schröder, M; Schultz-Coulon, H C; Schulz, M; Schumacher, M; Schwick, C; Scott, W G; Shears, T G; Shen, B C; Shepherd-Themistocleous, C H; Sherwood, P; Siroli, G P; Sittler, A; Skillman, A; Skuja, A; Smith, A M; Snow, G A; Sobie, Randall J; Söldner-Rembold, S; Springer, R W; Sproston, M; Stephens, K; Steuerer, J; Stockhausen, B; Stoll, K; Strom, D; Szymanski, P; Tafirout, R; Talbot, S D; Tanaka, S; Taras, P; Tarem, S; Teuscher, R; Thiergen, M; Thomson, M A; Von Törne, E; Towers, S; Trigger, I; Tsur, E; Turcot, A S; Turner-Watson, M F; Utzat, P; Van Kooten, R; Verzocchi, M; Vikas, P; Vokurka, E H; Voss, H; Wäckerle, F; Wagner, A; Ward, C P; Ward, D R; Watkins, P M; Watson, A T; Watson, N K; Wells, P S; Wermes, N; White, J S; Wilkens, B; Wilson, G W; Wilson, J A; Wolf, G; Wyatt, T R; Yamashita, S; Yekutieli, G; Zacek, V; Zer-Zion, D

    1997-01-01

    We have searched for decays of the tau lepton into seven or more charged particles, using data collected with the OPAL detector from 1990 to 1995 in e^+e^- collisions at sqrt(s) ~ M_Z. No candidate events were found and an upper limit on the branching ratio for tau decays into seven charged particles of 1.8 x 10^-5 at the 95% confidence level was determined.

  1. Measurement of the Double-Beta Decay Half-Life and Search for the Neutrinoless Double-Beta Decay of $^{48}{\\rm Ca}$ with the NEMO-3 Detector

    CERN Document Server

    :,; Augier, C; Bakalyarov, A M; Baker, J D; Barabash, A S; Basharina-Freshville, A; Blondel, S; Blot, S; Bongrand, M; Brudanin, V; Busto, J; Caffrey, A J; Calvez, S; Cascella, M; Cerna, C; Cesar, J P; Chapon, A; Chauveau, E; Chopra, A; Duchesneau, D; Durand, D; Egorov, V; Eurin, G; Evans, J J; Fajt, L; Filosofov, D; Flack, R; Garrido, X; Gómez, H; Guillon, B; Guzowski, P; Hodák, R; Huber, A; Hubert, P; Hugon, C; Jullian, S; Klimenko, A; Kochetov, O; Konovalov, S I; Kovalenko, V; Lalanne, D; Lang, K; Lebedev, V I; Lemière, Y; Noblet, T Le; Liptak, Z; Liu, X R; Loaiza, P; Lutter, G; Mamedov, F; Marquet, C; Mauger, F; Morgan, B; Mott, J; Nemchenok, I; Nomachi, M; Nova, F; Nowacki, F; Ohsumi, H; Pahlka, R B; Perrot, F; Piquemal, F; Povinec, P; Přidal, P; Ramachers, Y A; Remoto, A; Reyss, J L; Richards, B; Riddle, C L; Rukhadze, E; Rukhadze, N I; Saakyan, R; Salazar, R; Sarazin, X; Shitov, Yu; Simard, L; Šimkovic, F; Smetana, A; Smolek, K; Smolnikov, A; Söldner-Rembold, S; Soulé, B; Štekl, I; Suhonen, J; Sutton, C S; Szklarz, G; Thomas, J; Timkin, V; Torre, S; Tretyak, Vl I; Tretyak, V I; Umatov, V I; Vanushin, I; Vilela, C; Vorobel, V; Waters, D; Zhukov, S V; Žukauskas, A

    2016-01-01

    The NEMO-3 experiment at the Modane Underground Laboratory has investigated the double-$\\beta$ decay of $^{48}{\\rm Ca}$. Using $5.25$\\,yr of data recorded with a $6.99\\,{\\rm g}$ sample of $^{48}{\\rm Ca}$, approximately $150$ double-$\\beta$ decay candidate events have been selected with a signal-to-background ratio greater than $3$. The half-life for the two-neutrino double-$\\beta$ decay of $^{48}{\\rm Ca}$ has been measured to be \\mbox{$T^{2\

  2. Measurement of the double-beta decay half-life and search for the neutrinoless double-beta decay of $^{48}{\\rm Ca}$ with the NEMO-3 detector

    OpenAIRE

    Collaboration, NEMO-3; :; Arnold, R.; Augier, C.; Bakalyarov, A. M.; Baker, J. D.; Barabash, A. S.; Basharina-Freshville, A.; Blondel, S.; Blot, S; Bongrand, M.; Brudanin, V.(Joint Institute for Nuclear Research, Dubna, Russia); Busto, J.; Caffrey, A. J.; S. Calvez

    2016-01-01

    The NEMO-3 experiment at the Modane Underground Laboratory has investigated the double-$\\beta$ decay of $^{48}{\\rm Ca}$. Using $5.25$ yr of data recorded with a $6.99\\,{\\rm g}$ sample of $^{48}{\\rm Ca}$, approximately $150$ double-$\\beta$ decay candidate events have been selected with a signal-to-background ratio greater than $3$. The half-life for the two-neutrino double-$\\beta$ decay of $^{48}{\\rm Ca}$ has been measured to be $T^{2\

  3. Beta decay of the fission product 125Sb and a new complete evaluation of absolute gamma ray transition intensities

    Science.gov (United States)

    Rajput, M. U.; Ali, N.; Hussain, S.; Mujahid, S. A.; MacMahon, D.

    2012-04-01

    The radionuclide 125Sb is a long-lived fission product, which decays to 125Te by negative beta emission with a half-life of 1008 day. The beta decay is followed by the emission of several gamma radiations, ranging from low to medium energy, that can suitably be used for high-resolution detector calibrations, decay heat calculations and in many other applications. In this work, the beta decay of 125Sb has been studied in detail. The complete published experimental data of relative gamma ray intensities in the beta decay of the radionuclide 125Sb has been compiled. The consistency analysis was performed and discrepancies found at several gamma ray energies. Evaluation of the discrepant data was carried out using Normalized Residual and RAJEVAL methods. The decay scheme balance was carried out using beta branching ratios, internal conversion coefficients, populating and depopulating gamma transitions to 125Te levels. The work has resulted in the consistent conversion factor equal to 29.59(13) %, and determined a new evaluated set of the absolute gamma ray emission probabilities. The work has also shown 22.99% of the delayed intensity fraction as outgoing from the 58 d isomeric 144 keV energy level and 77.01% of the prompt intensity fraction reaching to the ground state from the other excited states. The results are discussed and compared with previous evaluations. The present work includes additional experimental data sets which were not included in the previous evaluations. A new set of recommended relative and absolute gamma ray emission probabilities is presented.

  4. Measurement of the Branching Fraction and Decay Rate Asymmetry of B to D_pi+ pi- pi0 K-

    Energy Technology Data Exchange (ETDEWEB)

    Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; /Annecy, LAPP; Grauges, E.; /Barcelona, IFAE; Palano, A.; Pappagallo, M.; Pompili, A.; /Bari U. /INFN, Bari; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; /Beijing, Inst. High Energy Phys.; Eigen, G.; Ofte, I.; Stugu, B.

    2005-06-10

    The authors report the observation of the decay B{sup -} {yields} D{sub {pi}{sup +}{pi}{sup -}{pi}{sup 0}}K{sup -}, where D{sub {pi}{sup +}{pi}{sup -}{pi}{sup 0}} indicates a neutral D meson detected in the final state {pi}{sup +}{pi}{sup -}{pi}{sup 0}, excluding K{sub S}{sup 0}{pi}{sup 0}. This doubly Cabibbo-suppressed decay chain can be used to measure the CKM phase {gamma}. Using about 229 million e{sup +}e{sup -} {yields} B{bar B} events recorded by the BABAR experiment at the PEP-II e{sup +}e{sup -} storage ring, they measure the branching fraction {Beta}(B{sup -} {yields} D{sub {pi}{sup +}{pi}{sup -}{pi}{sup 0}K{sup -}}) = (5.5 {+-} 1.0 (stat.) {+-} 0.7 (syst.)) x 10{sup -6} and the decay rate asymmetry A = -0.02 {+-} 0.16 (stat.) {+-} 0.03 (syst.) for the full decay chain.

  5. Semiconductor-based experiments for neutrinoless double beta decay search

    Science.gov (United States)

    Barnabé Heider, Marik; Gerda Collaboration

    2012-08-01

    Three experiments are employing semiconductor detectors in the search for neutrinoless double beta (0νββ) decay: COBRA, Majorana and GERDA. COBRA is studying the prospects of using CdZnTe detectors in terms of achievable energy resolution and background suppression. These detectors contain several ββ emitters and the most promising for 0νββ-decay search is 116Cd. Majorana and GERDA will use isotopically enriched high purity Ge detectors to search for 0νββ-decay of 76Ge. Their aim is to achieve a background ⩽10-3 counts/(kgṡyṡkeV) at the Q improvement compared to the present state-of-art. Majorana will operate Ge detectors in electroformed-Cu vacuum cryostats. A first cryostat housing a natural-Ge detector array is currently under preparation. In contrast, GERDA is operating bare Ge detectors submerged in liquid argon. The construction of the GERDA experiment is completed and a commissioning run started in June 2010. A string of natural-Ge detectors is operated to test the complete experimental setup and to determine the background before submerging the detectors enriched in 76Ge. An overview and a comparison of these three experiments will be presented together with the latest results and developments.

  6. Data Evaluation for 56Co epsilon + beta+ Decay

    Energy Technology Data Exchange (ETDEWEB)

    Baglin, Coral M.; MacMahon, T. Desmond

    2005-02-28

    Recommended values for nuclear and atomic data pertaining to the {var_epsilon} + {beta}{sup +} decay of {sup 56}Co are provided here, followed by comments on evaluation procedures and a summary of all available experimental data. {sup 56}Co is a radionuclide which is potentially very useful for Ge detector efficiency calibration because it is readily produced via the {sup 56}Fe(p,n) reaction, its half-life of 77.24 days is conveniently long, and it provides a number of relatively strong {gamma} rays with energies up to {approx}3500 keV. The transition intensities recommended here for the strongest lines will be included in the forthcoming International Atomic Energy Agency Coordinated Research Programme document ''Update of X- and Gamma-ray Decay Data Standards for Detector Calibration and Other Applications'', and the analysis for all transitions along with relevant atomic data have been provided to the Decay Data Evaluation Project.

  7. Nab: a precise study of unpolarized neutron beta decay

    Science.gov (United States)

    Pocanic, Dinko; Nab Collaboration

    2015-10-01

    Nab is a program of measurements of unpolarized neutron decays at the Spallation Neutron Source, Oak Ridge, TN. Nab aims to determine a, the e- ν correlation with precision of δa / a =10-3 , and b, the Fierz interference term, with uncertainty δb ~= 3 ×10-3 . The set of available observables overconstrains neutron beta decay in the Standard Model (SM), opening the door to searches for evidence of possible SM extensions. Projected Nab results will lead to a new precise determination of the ratio λ =GA /GV , and to significant reductions in the allowed limits for both right- and left-handed scalar and tensor currents. Alternatively, Nab may detect a discrepancy from SM predictions consistent with certain realizations of supersymmetry. A long asymmetric spectrometer, optimized to achieve the required narrow proton momentum response function, is currently under construction. The apparatus is to be used in follow-up measurements (ABba experiment) of asymmetry observables A and B in polarized neutron decay. Nab is planned for beam readiness in 2016. We discuss the experiment's motivation, expected reach, design and method, and update its status. Work supported by NSF Grants PHY-1126683, 1205833, 1307328, 1506320, and others.

  8. Nuclear-structure aspects of double beta decay

    International Nuclear Information System (INIS)

    Neutrinoless double beta (0νββ) decay of nuclei is a process that requires the neutrino to be a massive Majorana particle and thus cannot proceed in the standard model of electro-weak interactions. Recent results of the neutrino-oscillation experiments have produced accurate information on the mixing of neutrinos and their squared mass differences. The 0νββ decay takes place in atomic nuclei where it can be observed, at least in principle, by underground neutrino experiments. The need of nuclei in observation of the 0νββ decay bears two facets: The nucleus serves as laboratory for detection but at the same time its complicated many-nucleon structure interferes strongly with the analysis of the experimental data. The information about the weak-interaction observables, like the neutrino mass, has to be filtered from the data through the nuclear matrix elements (NMEs). Hence, exact knowledge about the NMEs is of paramount importance in the analysis of the data provided by the expensive and time-consuming underground experiments.

  9. Estimations of beta-decay energies through the nuclidic chart by using neural network

    International Nuclear Information System (INIS)

    One of the main characteristics of unstable nuclei is beta-decay energy (Qβ). It is determined by different methods such as beta endpoint measurements, counting in coincidence with annihilation radiation, electron capture (EC)/β+ ratio method, method of gamma absorption with X-ray coincidence. Beta-decay energy is a roughly linear function of atomic and mass numbers. Due to the fact that artificial neural network (ANN) is sufficient for nonlinear function approximation, in this study by using the nuclear masses from Hartree–Fock–BCS method, Qβ values have been obtained by ANN. It is seen that the estimations of the ANN are consistent with the calculated data within some deviation. - Highlights: • Beta decay energy is characteristic of unstable nuclei. • Atomic masses of nuclei can be calculated by using beta decay energy. • Artificial neural network is capable for the estimation of beta decay energy

  10. Measurement of disintegration rate and decay branching ratio for nuclide 192Ir with β-, EC mixing decays by using 4πβ-γ coincidence counting

    International Nuclear Information System (INIS)

    The absolute disintegration rates for nuclide 192Ir were measured with a 4πβ-γ (HPGe) coincidence apparatus by using parameter method and extrapolation method. The final uncertainties obtained were 0.4% and 0.5% respectively for a confidence level of 99.7%. The method with which both the disintegration rate and the decay branching ratio can be measured for nuclides with β- and EC mixing decays was proposed and described. The β- branching ratio in 192Ir decays was measured being 0.9572. The final uncertainties of disintegration rates and β- decay branching ratio with this method were 1.5% and 1.8% respectively

  11. K-shell ionisation in the positron decay branch of 58Co

    International Nuclear Information System (INIS)

    The number of K-shell vacancies produced per positron emission has been measured for the #betta#+ decay branch of 58Co. The result, (16.6+-2.1) x 10-4 vacancies per positron, is in reasonable agreement with a recent independent measurement but is in severe disagreement with the latest theoretical prediction. (author)

  12. Measurement of double beta decay - experiments TGV and NEMO

    International Nuclear Information System (INIS)

    The group of experimentalists of FNSPE CTU Prague takes part in two experiments connected with double beta (ββ) decay - TGV and NEMO. Both experimental set-ups are placed in the Modane underground laboratory (France). Experiment TGV has two phases. TGV I is a measurement of ββ decay of 48Ca (β-β-) and TGV II is a measurement with 106Cd (EC/EC, β+β+, β+/EC). The design and performances of the TGV I apparatus have been already detailed elsewhere. Measurements of the ββ decay of 48Ca have been started in August of 1996. The processing of the experimental data (still in progress), covering almost one year exposition (8700 hours), led to the following value of the half-life of 2νββ of 48Ca, T1/2 (4.2-1.3+3.3) . 1019 years and to an estimate of a limit on the half-life of 0νββ of 48Ca, T1/2 > 1.5 . 1021 years (90% CL). The aim of the project TGV II is the measurement of ββ decay of 106Cd particularly 2νEC/EC mode. This decay, up to now not measured, is characterized by the emission of two X-rays with energy approx. 23 keV. Project should give also information on the other modes - β+β+, β+/EC and EC/EC accompanied by the emission of a Majoron. TGV II is based on new spectrometer consisting of 32 HPGe detectors similar to the TGV I spectrometer. The background measurement is now in progress. The start of measurement with 106Cd is planned from the end of 2000. FNSPE CTU also participates in NEMO collaboration. The goal of the experiment NEMO-3 is to be sensitive to a 0.1 eV Majorana neutrino mass by looking for the 0νββ process of 100Mo. Two prototypes NEMO-1 and NEMO-2 have been built. The NEMO-2 gave (after 6 years of data taking) physical results for 2νββdecay of 100Mo, 116Cd, 82Se and 96Zr. The installation of NEMO-3 detector started in the Modane underground laboratory and should be ready in summer 2000. (author)

  13. First neutrinoless double beta decay results from CUORE-0

    International Nuclear Information System (INIS)

    The CUORE-0 experiment, a 52 bolometer array searching for neutrinoless double beta decay from 130Te, has started taking data in spring 2013 underground at the Laboratori Nazionali del Gran Sasso (LNGS). The excellent results obtained in terms of energy resolution and background level allowed this experiment to reach the sensitivity of Cuoricino in approximately half the runtime. Combining CUORE-0 data (9.8 kg·yr exposure of 130Te) with the 19.75 kg·yr exposure of the Cuoricino experiment, we obtain the most stringent limit to date on the half-life of this isotope (T1/2 > 4.0 × 1024 yr). In this article, we review the results from CUORE-0 and discuss the status and the physics potential of CUORE, a 19 times larger bolometer array that plans to begin operations by end of this year

  14. Progress report on the Los Alamos tritium beta decay experiment

    International Nuclear Information System (INIS)

    Measurements near the endpoint of the tritium beta-decay spectrum using a gaseous molecular tritium source yield an essentially model-independent upper limit of 27 eV on the /ovr ν//sub e/ mass at the 95% confidence level. Since demonstrating from this initial measurement the successful operation of a gaseous source based system, most of our effort has been concentrated towards the upgrade and optimization of the experimental apparatus. The emphasis of this work has been to eliminate or further reduce effects that generate systematic errors. Based on realistic projections from our initial measurement, an ultimate sensitivity to neutrino mass of 10 eV is expected. 12 refs., 1 fig

  15. Improved estimate of the cross section for inverse beta decay

    CERN Document Server

    Ankowski, Artur M

    2016-01-01

    The hypothesis of the conserved vector current, relating the vector weak and isovector electromagnetic currents, plays a fundamental role in quantitative description of neutrino interactions. Despite being experimentally confirmed with great precision, it is not fully implemented in existing calculations of the cross section for inverse beta decay, the dominant mechanism of antineutrino scattering at energies below a few tens of MeV. In this article, I estimate the corresponding cross section and its uncertainty, ensuring conservation of the vector current. While converging to previous calculations at energies of several MeV, the obtained result is appreciably lower and predicts more directional positron production near the reaction threshold. These findings suggest that in the current estimate of the flux of geologically produced antineutrinos the 232Th and 238U components may be underestimated by 6.1 and 3.7%, respectively. The proposed search for light sterile neutrinos using a 144Ce--144Pr source is predi...

  16. An electroweak basis for neutrinoless double $\\beta$ decay

    CERN Document Server

    Graesser, Michael L

    2016-01-01

    A discovery of neutrinoless double-$\\beta$ decay would be profound, providing the first direct experimental evidence of lepton number violating processes. While a natural explanation is provided by an effective Majorana neutrino mass, other new physics interpretations should be carefully evaluated. At low--energies such new physics could manifest itself in the form of color and $SU(2)_L \\times U(1)_{Y}$ invariant higher dimension operators. Here we determine a complete set of electroweak invariant dimension--9 operators, and our analysis supersedes those that only impose $U(1)_{em}$ invariance. Imposing electroweak invariance implies: 1) a significantly reduced set of leading order operators compared to only imposing $U(1)_{em}$ invariance; and 2) other collider signatures. Prior to imposing electroweak invariance we find 32 dimension-9 operators, which is reduced to 15 electroweak invariant operators at leading order in the expansion in the Higgs vacuum expectation value. We set up a systematic analysis of t...

  17. Cryogenic Double Beta Decay Experiments: CUORE and CUORICINO

    CERN Document Server

    Maruyama, Reina

    2008-01-01

    Cryogenic bolometers, with their excellent energy resolution, flexibility in material, and availability in high purity, are excellent detectors for the search for neutrinoless double beta decay. Kilogram-size single crystals of TeO_2 are utilized in CUORICINO for an array with a total detector mass of 40.7 kg. CUORICINO currently sets the most stringent limit on the halflife of Te-130 of T > 2.4x10^{24} yr (90% C.L.), corresponding to a limit on the effective Majorana neutrino mass in the range of < 0.2-0.9 eV. Based on technology developed for CUORICINO and its predecessors, CUORE is a next-generation experiment designed to probe neutrino mass in the range of 10 - 100 meV. Latest results from CUORICINO and overview of the progress and current status of CUORE are presented.

  18. Neutrinoless double-beta decay in covariant density functional theory

    Science.gov (United States)

    Ring, P.; Yao, J. M.; Song, L. S.; Hagino, K.; Meng, J.

    2015-10-01

    We use covariant density functional theory beyond mean field in order to describe neutrinoless double-beta decay in a fully relativistic way. The dynamic effects of particle-number and angular-momentum conservations as well as shape fluctuations of quadrupole character are taken into account within the generator coordinate method for both initial and final nuclei. The calculations are based on the full relativistic transition operator. The nuclear matrix elements (NME's) for a large number of possible transitions are investigated. The results are compared with various non-relativistic calculations, in particular also with the density functional theory based on the Gogny force. We find that the non-relativistic approximation is justified and that the total NME's can be well approximated by the pure axial-vector coupling term. This corresponds to a considerable reduction of the computational effort.

  19. Neutrinoless double-beta decay in covariant density functional theory

    Energy Technology Data Exchange (ETDEWEB)

    Ring, P., E-mail: ring@ph.tum.de [Physik-Department der Technischen Universität München, D-85748 Garching (Germany); State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking Univ., Beijing 100871 (China); Yao, J. M. [Department of Physics, Tohoku University, Sendai 980-8578 (Japan); School of Physical Science and Technology, Southwest University, Chongqing 400715 (China); Song, L. S. [State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking Univ., Beijing 100871 (China); Hagino, K. [Department of Physics, Tohoku University, Sendai 980-8578 (Japan); Meng, J. [State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking Univ., Beijing 100871 (China); School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191 (China); Department of Physics, University of Stellenbosch, Stellenbosch 7602 (South Africa)

    2015-10-15

    We use covariant density functional theory beyond mean field in order to describe neutrinoless double-beta decay in a fully relativistic way. The dynamic effects of particle-number and angular-momentum conservations as well as shape fluctuations of quadrupole character are taken into account within the generator coordinate method for both initial and final nuclei. The calculations are based on the full relativistic transition operator. The nuclear matrix elements (NME’s) for a large number of possible transitions are investigated. The results are compared with various non-relativistic calculations, in particular also with the density functional theory based on the Gogny force. We find that the non-relativistic approximation is justified and that the total NME’s can be well approximated by the pure axial-vector coupling term. This corresponds to a considerable reduction of the computational effort.

  20. Neutrinoless double-beta decay in covariant density functional theory

    International Nuclear Information System (INIS)

    We use covariant density functional theory beyond mean field in order to describe neutrinoless double-beta decay in a fully relativistic way. The dynamic effects of particle-number and angular-momentum conservations as well as shape fluctuations of quadrupole character are taken into account within the generator coordinate method for both initial and final nuclei. The calculations are based on the full relativistic transition operator. The nuclear matrix elements (NME’s) for a large number of possible transitions are investigated. The results are compared with various non-relativistic calculations, in particular also with the density functional theory based on the Gogny force. We find that the non-relativistic approximation is justified and that the total NME’s can be well approximated by the pure axial-vector coupling term. This corresponds to a considerable reduction of the computational effort

  1. First neutrinoless double beta decay results from CUORE-0

    Science.gov (United States)

    Gironi, L.; Alduino, C.; Alfonso, K.; Artusa, D. R.; Avignone, F. T.; Azzolini, O.; Balata, M.; Banks, T. I.; Bari, G.; Beeman, J. W.; Bellini, F.; Bersani, A.; Biassoni, M.; Brofferio, C.; Bucci, C.; Camacho, A.; Caminata, A.; Canonica, L.; Cao, X. G.; Capelli, S.; Cappelli, L.; Carbone, L.; Cardani, L.; Carniti, P.; Casali, N.; Cassina, L.; Chiesa, D.; Chott, N.; Clemenza, M.; Copello, S.; Cosmelli, C.; Cremonesi, O.; Creswick, R. J.; Cushman, J. S.; Dafinei, I.; Dally, A.; Davis, C. J.; Dell'Oro, S.; Deninno, M. M.; Di Domizio, S.; Di Vacri, M. L.; Drobizhev, A.; Fang, D. Q.; Faverzani, M.; Fernandes, G.; Ferri, E.; Ferroni, F.; Fiorini, E.; Franceschi, M. A.; Freedman, S. J.; Fujikawa, B. K.; Giachero, A.; Giuliani, A.; Gorla, P.; Gotti, C.; Gutierrez, T. D.; Haller, E. E.; Han, K.; Hansen, E.; Heeger, K. M.; Hennings-Yeomans, R.; Hickerson, K. P.; Huang, H. Z.; Kadel, R.; Keppel, G.; Kolomensky, Yu. G.; Ligi, C.; Lim, K. E.; Liu, X.; Ma, Y. G.; Maino, M.; Martinez, M.; Maruyama, R. H.; Mei, Y.; Moggi, N.; Morganti, S.; Napolitano, T.; Nisi, S.; Nones, C.; Norman, E. B.; Nucciotti, A.; O'Donnell, T.; Orio, F.; Orlandi, D.; Ouellet, J. L.; Pagliarone, C. E.; Pallavicini, M.; Palmieri, V.; Pattavina, L.; Pavan, M.; Pessina, G.; Pettinacci, V.; Piperno, G.; Pira, C.; Pirro, S.; Pozzi, S.; Previtali, E.; Rosenfeld, C.; Rusconi, C.; Sala, E.; Sangiorgio, S.; Santone, D.; Scielzo, N. D.; Sisti, M.; Smith, A. R.; Taffarello, L.; Tenconi, M.; Terranova, F.; Tomei, C.; Trentalange, S.; Ventura, G.; Vignati, M.; Wagaarachchi, S. L.; Wang, B. S.; Wang, H. W.; Wielgus, L.; Wilson, J.; Winslow, L. A.; Wise, T.; Woodcraft, A.; Zanotti, L.; Zarra, C.; Zhang, G. Q.; Zhu, B. X.; Zimmermann, S.; Zucchelli, S.

    2015-10-01

    The CUORE-0 experiment, a 52 bolometer array searching for neutrinoless double beta decay from 130Te, has started taking data in spring 2013 underground at the Laboratori Nazionali del Gran Sasso (LNGS). The excellent results obtained in terms of energy resolution and background level allowed this experiment to reach the sensitivity of Cuoricino in approximately half the runtime. Combining CUORE-0 data (9.8 kg.yr exposure of 130Te) with the 19.75 kg.yr exposure of the Cuoricino experiment, we obtain the most stringent limit to date on the half-life of this isotope (T1/2 > 4.0 × 1024 yr). In this article, we review the results from CUORE-0 and discuss the status and the physics potential of CUORE, a 19 times larger bolometer array that plans to begin operations by end of this year.

  2. Transition-edge microcalorimeter for tritium beta decay

    International Nuclear Information System (INIS)

    We are conducting a new tritium beta-decay experiment using a cryogenic microcalorimeter. The microcalorimeter consists of a copper foil with an implanted tritium source. The foil is soldered to a thin film gold pad on a silicon wafer that is in thermal contact with an aluminum/silver bilayer transition-edge sensor. The device is voltage biased with current pulses read out using a SQUID magnetometer. The device has been tested with external sources as well as an implanted tritium source. The device is currently too slow to set a meaningful limit on the square of the neutrino mass, but can be made fast enough to set a limit on the order of 10 eV

  3. Beta-Decay Correlations in the LHC Era

    CERN Document Server

    Bodek, Kazimierz

    2016-01-01

    Neutron and nuclear beta decay correlation coefficients are linearly sensitive to the exotic scalar and tensor interactions that are not included in the Standard Model. The proposed experiment will measure simultaneously 11 neutron correlation coefficients ($a$, $A$, $B$, $D$, $H$, $L$, $N$, $R$, $S$, $U$, $V$) where 5 of them ($H$, $L$, $S$, $U$, $V$) were never addressed before. Silicon pixel detectors are considered as promising alternative to multi-wire gas chambers devoted for electron tracking in the original setup. The expected sensitivity limits for $\\epsilon_S$ and $\\epsilon_T$ -- EFT parameters describing the scalar and tensor contributions to be extracted from the transverse electron polarization related coefficients $H$, $L$, $N$, $R$, $S$, $U$, $V$ are discussed.

  4. First neutrinoless double beta decay results from CUORE-0

    Energy Technology Data Exchange (ETDEWEB)

    Gironi, L., E-mail: luca.gironi@mib.infn.it; Biassoni, M.; Brofferio, C.; Capelli, S.; Carniti, P.; Cassina, L.; Chiesa, D.; Clemenza, M.; Faverzani, M.; Ferri, E.; Gotti, C.; Maino, M.; Nucciotti, A.; Pavan, M.; Pozzi, S.; Sala, E.; Sisti, M.; Terranova, F.; Zanotti, L. [Dipartimento di Fisica, Università di Milano-Bicocca, Milano I-20126 - Italy (Italy); INFN - Sezione di Milano Bicocca, Milano I-20126 - Italy (Italy); Alduino, C. [Department of Physics and Astronomy, University of South Carolina, Columbia, SC 29208 - USA (United States); and others

    2015-10-28

    The CUORE-0 experiment, a 52 bolometer array searching for neutrinoless double beta decay from {sup 130}Te, has started taking data in spring 2013 underground at the Laboratori Nazionali del Gran Sasso (LNGS). The excellent results obtained in terms of energy resolution and background level allowed this experiment to reach the sensitivity of Cuoricino in approximately half the runtime. Combining CUORE-0 data (9.8 kg·yr exposure of {sup 130}Te) with the 19.75 kg·yr exposure of the Cuoricino experiment, we obtain the most stringent limit to date on the half-life of this isotope (T{sub 1/2} > 4.0 × 10{sup 24} yr). In this article, we review the results from CUORE-0 and discuss the status and the physics potential of CUORE, a 19 times larger bolometer array that plans to begin operations by end of this year.

  5. Recent results from cosmology and neutrinoless double beta decay

    Science.gov (United States)

    Dell’Oro, Stefano; Marcocci, Simone

    2016-05-01

    We quantify the impact of cosmological surveys on the search for neutrinoless double beta decay (0vββ) within the hypothesis that the 0vββ rate is dominated by the Majorana mass of ordinary neutrinos. In particular, we exploit the potential relevance of the work of Palanque-Delabrouille et al. [JCAP 1502, 045 (2015)], whose result seems to favor the normal hierarchy spectrum for the light neutrino masses. The impact of our analysis for the future generation of 0vββ experiments is quite dramatic and motivates further cosmological studies, both theoretically and experimentally. In fact, the allowed values for the Majorana Effective Mass turn out to be < 75meV at 3σ C.L, lowering down to less than 20 meV at 1σ C.L.

  6. Nuclear transparency and double beta decay of molybdenum 100

    International Nuclear Information System (INIS)

    Work is continuing on two collaborative experiments. One, a search for double beta decay in molybdenum 100 is being carried out in the Consil silver mine in Osburn, Idaho with collaborators from the Lawrence Berkeley Laboratory, the University of New Mexico, and the Idaho National Engineering Laboratory. At this time the experiment is running with 62 foils, each with a mass of about .98 grams of isotopically enriched molybdenum 100. In approximately 1870 hours of data taking which began during the spring 1991 we have obtained a preliminary 1σ lower limit of .12 x 1023 years for the lifetime for O+ → O+ neutrionoless double beta decay in molybdenum 100 based on an estimate for the event detection efficiency of the upgraded detector. This lifetime limit is 3 times greater that the one we published previously in Physical Review Letters in 1989. Monte Carlo Efforts are currently underway to determine the event detector efficiency more precisely. The second experiment involves the construction of a cylindrically symmetrical detector at the Brookhaven National Laboratory AGS to study color transparency in nuclei from 6 to 20 GeV/c. This detector consists of a large superconducting solenoidal magnet, a cylinder of scintillating fibers, several cylinders of straw tubes, and an array of trigger plastic scintillator hodoscopes. Mount Holyoke has been principally involved in the design of phototube bases for the trigger hodoscopes for the EVA detector and in the design and construction of the scintillating fiber detector tracking detector. A prototype fiber detector consisting of 2 Hamamatsu multianode photomultiplier tubes with 256 channels each and approximately 650 1.5 meter long 1 mm diameter scintillating fibers broken up into two layers and supported by a 10 centimeter diameter carbon fiber tube was constructed for the spring high energy physics run at the AGS. Data from this run obtained from the detector is included in this report

  7. Estimates of the branching ratios for hadronic decays of heavy resonances using quark combinatorics

    International Nuclear Information System (INIS)

    The quark combinatorics method [V. V. Anisovich et al., Nucl. Phys. B55, 455 (1973); J. D. Bjorken et al., Phys. Rev. D9, 1449 (1974)] at finite energies [V. N. Guman et al., Nucl. Phys. B99, 532 (1975), S. A. Voloshin et al., Sov. J. Nucl. Phys. 35, 586, 738 (1982)] is used to estimate the branching ratios for hadronic decays of the heavy resonances J/psi, D+, D0, F+, and Λ+/sub c/. The results are compared to the experimental data on the known hadronic decay channels of the J/psi, D+, and D0 mesons. The branching ratios for the hadronic decays of the F+ meson and the Λ+/sub c/ hyperon are predicted

  8. Project 8: Determining neutrino mass from tritium beta decay using a frequency-based method

    Energy Technology Data Exchange (ETDEWEB)

    Doe, Peter J.; Kofron, Jared N.; MCBride, Lisa; Robertson, R. G. H.; Rosenberg, Leslie; Rybka, Gray; Doelman, S.; Rogers, Alan E.; Formaggio, Joseph; Furse, Daniel; Oblath, Noah S.; LaRoque, Benjamin; Leber, Michelle; Monreal, Ben; Bahr, Matthew; Asner, David M.; Jones, Anthony M.; Fernandes, Justin L.; VanDevender, Brent A.; Patterson, Ryan B.; Bradley, Rich; Thummler, Thomas

    2013-10-04

    A general description is given of Project 8, a new approach to measuring the neutrino mass scale via the beta decay of tritium. In Project 8, the energy of electrons emitted in beta decay is determined from the frequency of cyclotron radiation emitted as the electrons spiral in a uniform magnetic field

  9. Project 8: Determining neutrino mass from tritium beta decay using a frequency-based method

    CERN Document Server

    Doe, P J; McBride, E L; Robertson, R G H; Rosenberg, L J; Rybka, G; Doelman, S; Rogers, A; Formaggio, J A; Furse, D; Oblath, N S; LaRoque, B H; Leber, M; Monreal, B; Bahr, M; Asner, D M; Jones, A M; Fernandes, J; VanDevender, B A; Patterson, R; Bradley, R; Thuemmler, T

    2013-01-01

    A general description is given of Project 8, a new approach to measuring the neutrino mass scale via the beta decay of tritium. In Project 8, the energy of electrons emitted in beta decay is determined from the frequency of cyclotron radiation emitted as the electrons spiral in a uniform magnetic field.

  10. $\\beta$3p- spectroscopy and P-$\\gamma$ width determination in the decay of $^{31}$Ar

    CERN Multimedia

    We propose to perform a detailed study of the $\\beta$-decay of the dripline nucleus $^{31}$Ar. This will allow a detailed study of the $\\beta$-delayed 3p-decay as well as provide important information on the resonances of $^{30}$S and $^{29}$P, in particular the ratio between the P- and $\\gamma$- partial widths relevant for astrophysics.

  11. The GT resonance revealed in beta sup + -decay using new experimental techniques

    CERN Document Server

    Algora, A; Rubio, B; Taín, J L; Agramunt, J; Blomqvist, J M; Batist, L; Borcea, R; Collatz, R; Gadea, A; Gerl, J; Gierlik, M; aGórska, M; Guilbaud, O; Grawe, H; Hellström, M; Hu, Z; Janas, Z; Karny, M; Kirchner, R; Kleinheinz, P; Liu, W; Martínez, T; Moroz, F; Plochocki, A; Rejmund, M; Roeckl, E; Rykaczewski, K; Shibata, M; Szerypo, J; Wittmann, V

    1999-01-01

    The GT beta decay of sup 1 sup 5 sup 0 Ho has been studied with a Total Absorption Spectrometer (TAS), with an array of 6 Euroball CLUSTER Ge detectors (the CLUSTER CUBE), and with an alpha detector. The three techniques complement each other. The results provide the first observation of an extremely sharp resonance in GT beta decay.

  12. $\\beta$-asymmetry measurements in nuclear $\\beta$-decay as a probe for non-standard model physics

    CERN Multimedia

    Roccia, S

    2002-01-01

    We propose to perform a series of measurements of the $\\beta$-asymmetry parameter in the decay of selected nuclei, in order to investigate the presence of possible time reversal invariant tensor contributions to the weak interaction. The measurements have the potential to improve by a factor of about four on the present limits for such non-standard model contributions in nuclear $\\beta$-decay.

  13. Novel nuclear structure aspects of the O{nu}{beta}{beta}-decay

    Energy Technology Data Exchange (ETDEWEB)

    Menendez, J; Poves, A [Departamento de Fisica Teorica, and IFT, UAM-CSIC, Universidad Autonoma de Madrid, 28049-Madrid (Spain); Caurier, E; Nowacki, F, E-mail: alfredo.poves@uam.es [IPHC, IN2P3-CNRS/Universite Louis Pasteur, 67037-Strasbourg (France)

    2011-01-01

    We explore the influence of the deformation on the nuclear matrix elements of the neutrinoless double beta decay (NME), concluding that the difference in deformation -or more generally in the amount of quadrupole correlations- between parent and grand daughter nuclei quenches strongly the decay. We correlate these differences with the seniority structure of the nuclear wave functions. In this context, we examine the present discrepancies between the NME's obtained in the framework of the Interacting Shell Model and the Quasiparticle RPA. In our view, part of the discrepancy can be due to the limitations of the spherical QRPA in treating nuclei which have strong quadrupole correlations. We surmise that the NME's in a basis of generalized seniority are approximately model independent, i. e. they are 'universal'.

  14. Energy density functional study of nuclear matrix elements for neutrinoless $\\beta\\beta$ decay

    CERN Document Server

    Rodríguez, Tomás R

    2010-01-01

    We present an extensive study of nuclear matrix elements (NME) for the neutrinoless double beta decay of the nuclei $^{48}$Ca, $^{76}$Ge, $^{82}$Se, $^{96}$Zr, $^{100}$Mo, $^{124}$Sn, $^{128}$Te, $^{130}$Te, $^{136}$Xe, and $^{150}$Nd based on state-of-the-art energy density functional methods using the Gogny D1S functional. Beyond mean-field effects are included within the generating coordinate method with particle number and angular momentum projection for both initial and final ground states. We obtain a rather constant value for the NME's around 4.7 with the exception of $^{48}$Ca and $^{150}$Nd, where smaller values are found. We analyze the role of deformation and pairing in the evaluation of the NME and present detailed results for the decay of $^{150}$Nd.

  15. Study of Branching Ratio And Polarization Fraction in Neutral B Meson Decays to Negative Rho Meson Positive Kaon Resonance

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Baosen; /Wisconsin U., Madison

    2006-03-07

    We present the preliminary results on the search for B{sup 0} {yields} {rho}{sup -}K*{sup +}. The data sample comprises 122.7 million B{bar B} pairs in the e{sup +}e{sup -} annihilation through the {Upsilon}(4S) resonance collected during 1999-2003 with the BABAR detector at the PEP-II asymmetric-energy collider at Stanford Linear Accelerator Center (SLAC). We obtain an upper limit of the branching ratio at 90% confidence level as {Beta}(B{sup 0} {yields} {rho}{sup -}K*{sup +}) < 17.2 x 10{sup -6}. The fitted result on the polarization fraction shows no evidence that the decay is longitudinally dominated as predicted by various theoretical models.

  16. LUCIFER: Neutrinoless Double Beta decay search with scintillating bolometers

    International Nuclear Information System (INIS)

    One of the fundamental open questions in elementary particle physics is the value of the neutrino mass and its nature of Dirac or Majorana particle. Neutrinoless double beta decay (DBD0ν) is a key tool for investigating these neutrino properties and for finding answers to the open questions concerning mass hierarchy and absolute scale. Experimental techniques based on the calorimetric approach with cryogenic particle detectors are proved to be suitable for the search of this rare decay, thanks to high energy resolution and large mass of the detectors. One of the main issues to access an increase of the experimental sensitivity is strictly related to background reduction, trying to perform possibly a zero background experiment. The LUCIFER (Low-background Underground Cryogenic Installation For Elusive Rates) project, funded by the European Research Council, aims at building a background-free DBD0ν experiment, with a discovery potential comparable with the present generation experiments. The idea of LUCIFER is to measure, simultaneously, heat and scintillation light with ZnSe bolometers. Detector features and operational procedures are reviewed. The expected performances and sensitivity are also discussed.

  17. Search for the Neutrino Less Double Beta Decay

    Energy Technology Data Exchange (ETDEWEB)

    Efremenko, Yuri [Univ. of Tennessee, Knoxville, TN (United States). Dept. of Physics and Astronomy

    2016-07-11

    During the past few years our understanding of neutrino properties has reached a new level, with experiments such as Super-K, SNO, KamLAND, and others obtaining exciting results. Major questions such as “Do neutrinos have mass?” and “Do neutrinos oscillate?” now have positive answers. However, an extensive program of neutrino research remains. Undoubtedly, the most important of these is the question pointed out by the National Research Council in its February 2002 report “Connecting Quarks with the Cosmos”, specifically: What are the masses of neutrinos and how have they shaped the evolution of the Universe? The MAJORANA collaboration has proposed to build the world’s most sensitive one-ton scale experiment to search for neutrino less double beta decay to answer this question. In its initial stage, the collaboration is building a prototype MAJORANA DEMONSTRATOR (MJD) experiment consisting of detectors made out of enriched Ge76 with a total sensitive mass of ~30 kg. This will accomplish two goals. First, it will test not yet confirmed claim for observation of neutrino-less double beta decay. Second, it will establish that the selected technology is capable of extension to a one-ton experiment with sufficient sensitivity to measure neutrino mass mββ down to 10 meV. To achieve the last goal, collaboration must demonstrate that a background level of 1 count per year per 4 keV per ton of detector is achievable. The University of Tennessee (UT) neutrino group has made a major commitment to the MJD. P.I. accepted the responsibility for one of the major tasks of the experiment, “Materials and Assay Task” which is crucial to the achievement of low background levels required for the experiment. In addition, the UT group is committed to construct, commission, and operate the MJD active veto system. Those activities were supported by NP-DOE via program funding for “Search for the Neutrino Less Double Beta Decay” at the University

  18. Large-scale calculations of the beta-decay rates and r-process nucleosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Borzov, I.N.; Goriely, S. [Inst. d`Astronomie et d`Astrophysique, Univ. Libre de Bruxelles, Campus Plaine, Bruxelles (Belgium); Pearson, J.M. [Inst. d`Astronomie et d`Astrophysique, Univ. Libre de Bruxelles, Campus Plaine, Bruxelles (Belgium)]|[Lab. de Physique Nucleaire, Univ. de Montreal, Montreal (Canada)

    1998-06-01

    An approximation to a self-consistent model of the ground state and {beta}-decay properties of neutron-rich nuclei is outlined. The structure of the {beta}-strength functions in stable and short-lived nuclei is discussed. The results of large-scale calculations of the {beta}-decay rates for spherical and slightly deformed nuclides of relevance to the r-process are analysed and compared with the results of existing global calculations and recent experimental data. (orig.)

  19. Probing New Physics Models of Neutrinoless Double Beta Decay with SuperNEMO

    CERN Document Server

    Arnold, R; Baker, J; Barabash, A S; Basharina-Freshville, A; Bongrand, M; Brudanin, V; Caffrey, A J; Cebrián, S; Chapon, A; Chauveau, E; Dafni, Th; Deppisch, F F; Diaz, J; Durand, D; Egorov, V; Evans, J J; Flack, R; Fushima, K-I; Irastorza, I García; Garrido, X; Gómez, H; Guillon, B; Holin, A; Holy, K; Horkey, J J; Hubert, Ph; Hugon, C; Iguaz, F J; Ishihara, N; Jackson, C M; Jullian, S; Kauer, M; Kochetov, O; Konovalov, S I; Kovalenko, V; Lamhamdi, T; Lang, K; Lutter, G; Luzón, G; Mamedov, F; Marquet, Ch; Mauger, F; Monrabal, F; Nachab, A; Nasteva, I; Nemchenok, I; Nguyen, C H; Nomachi, M; Nova, F; Ohsumi, H; Pahlka, R B; Perrot, F; Piquemal, F; Povinec, P P; Richards, B; Ricol, J S; Riddle, C L; Rodríguez, A; Saakyan, R; Sarazin, X; Sedgbeer, J K; Serra, L; Shitov, Yu; Simard, L; Šimkovic, F; Söldner-Rembold, S; Štekl, I; Sutton, C S; Tamagawa, Y; Thomas, J; Timkin, V; Tretyak, V; Tretyak, Vl I; Umatov, V I; Vanyushin, I A; Vasiliev, R; Vasiliev, V; Vorobel, V; Waters, D; Yahlali, N; Žukauskas, A

    2010-01-01

    The possibility to probe new physics scenarios of light Majorana neutrino exchange and right-handed currents at the planned next generation neutrinoless double beta decay experiment SuperNEMO is discussed. Its ability to study different isotopes and track the outgoing electrons provides the means to discriminate different underlying mechanisms for the neutrinoless double beta decay by measuring the decay half-life and the electron angular and energy distributions.

  20. Stellar $\\beta^{\\pm}$ decay rates of iron isotopes and its implications in astrophysics

    OpenAIRE

    Nabi, Jameel-Un

    2014-01-01

    $\\beta$-decay and positron decay are believed to play a consequential role during the late phases of stellar evolution of a massive star culminating in a supernova explosion. Recently the microscopic calculation of weak-interaction mediated rates on key isotopes of iron was introduced using the proton-neutron quasiparticle random phase approximation (pn-QRPA) theory with improved model parameters. Here I discuss in detail the improved calculation of $\\beta^{\\pm}$ decay rates for iron isotopes...

  1. Estimation of the branching ratios for hadronic decays of heavy resonances by means of the quark combinatorics

    International Nuclear Information System (INIS)

    The hadronic channel decay branching ratios for the heavy resonances J/psi, D+, D0, F+, and Λsub(c)sup(+) are calculated using the quark combinatorics method at finite energies. The calculation results are compared to the data on known hadronic decay channels of the J/psi, D+, and D0 mesons. The F+ and Λsub(c)sup(+) hadronic decay branching ratios are predicted

  2. High efficiency beta-decay spectroscopy using a planar germanium double-sided strip detector

    International Nuclear Information System (INIS)

    Beta-decay spectroscopy experiments are limited by the detection efficiency of ions and electrons in the experimental setup. While there is a variety of different experimental setups in use for beta-decay spectroscopy, one popular choice is silicon double-sided strip detectors (DSSD). The higher Z of Ge and greater availability of thicker detectors as compared to Si potentially offer dramatic increases in the detection efficiency for beta-decay electrons. In this work, a planar GeDSSD has been commissioned for use in beta-decay spectroscopy experiments at the National Superconducting Cyclotron Laboratory (NSCL). The implantation response of the detector and its beta-decay detection efficiency is discussed. -- Highlights: • A planar Ge double-sided strip detector is implemented for decay spectroscopy. • Dual range preamplifiers provide sensitivity to both heavy ions and beta-decay electrons. • Beta-decay electron detection efficiencies greater than 50% are demonstrated. • Based on comparisons with simulation, an efficiency of roughly 90% is expected

  3. K-shell ionisation in the positron decay branch of 68Ga

    International Nuclear Information System (INIS)

    The number of K-shell vacancies produced per positron emitted in the β+ decay branch of 68Ga has been found to be (10.3 +- 1.0) x 10-4. This is 50% higher than the prediction of the theory of Law and Suzuki (1982 Phys. Rev. C 25, 514), which has proved successful in β- decay, and confirms the trend of the experimental results obtained in the three other positron decays which have so far been investigated. The importance of the final-state interaction in β+ decay has recently been shown theoretically by other authors, and a successful theory will probably require a combination of their approach with that of Law and Suzuki, which emphasises many-body effects. (author)

  4. Measurements of the branching fractions and CP-asymmetries of B- --> D0_(CP) K- decays

    OpenAIRE

    The BABAR Collaboration; Aubert, B.

    2005-01-01

    We present a study of the decay B- --> D0_(CP) K- and its charge conjugate, where D0_(CP) is reconstructed in CP-even, CP-odd, and non-CP flavor eigenstates, based on a sample of 232 million Y(4S) --> B Bbar decays collected with the BABAR detector at the PEP-II e+e- storage ring. We measure the partial-rate charge asymmetries A_CP+, A_CP- and the ratios R_CP+, R_CP- of the B --> D0 K decay branching fractions as measured in CP+, CP-, and non-CP D0 decays: A_CP+ = 0.35 +/- 0.13 (stat) +/- 0.0...

  5. Measurement of Branching Fractions and Rate Asymmetries in the Rare Decays B -> K(*) l+ l-

    OpenAIRE

    The BABAR Collaboration

    2012-01-01

    In a sample of 471 million BB events collected with the BABAR detector at the PEP-II e+e- collider we study the rare decays B -> K(*) l+ l-, where l+ l- is either e+e- or mu+mu-. We report results on partial branching fractions and isospin asymmetries in seven bins of di-lepton mass-squared. We further present CP and lepton-flavor asymmetries for di-lepton masses below and above the J/psi resonance. We find no evidence for CP or lepton-flavor violation. The partial branching fractions and iso...

  6. Branching Fraction for the Doubly-Cabibbo-Suppressed Decay D^+ --> K^+ pi^0

    CERN Document Server

    Dytman, S; Savinov, V; Aquines, O; Li, Z; López, A; Mehrabyan, S S; Méndez, H; Ramírez, J; Huang, G S; Miller, D H; Pavlunin, V; Sanghi, B; Shipsey, I P J; Xin, B; Adams, G S; Anderson, M; Cummings, J P; Danko, I; Napolitano, J; He, Q; Insler, J; Muramatsu, H; Park, C S; Thorndike, E H; Yang, F; Coan, T E; Gao, Y S; Liu, F; Artuso, M; Blusk, S; Butt, J; Li, J; Menaa, N; Mountain, R; Nisar, S; Randrianarivony, K; Redjimi, R; Sia, R; Skwarnicki, T; Stone, S; Wang, J C; Zhang, K; Csorna, S E; Bonvicini, G; Cinabro, D; Dubrovin, M; Lincoln, A; Asner, D M; Edwards, K W; Briere, R A; Brock, I; Chen, J; Ferguson, T; Tatishvili, G T; Vogel, H; Watkins, M E; Rosner, J L; Adam, N E; Alexander, J P; Berkelman, K; Cassel, D G; Duboscq, J E; Ecklund, K M; Ehrlich, R; Fields, L; Gibbons, L; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Mahlke-Krüger, H; Onyisi, P U E; Patterson, J R; Peterson, D; Pivarski, J; Riley, D; Ryd, A; Sadoff, A J; Schwarthoff, H; Shi, X; Stroiney, S; Sun, W M; Wilksen, T; Weinberger, M; Athar, S B; Patel, R; Potlia, V; Yelton, J; Rubin, P; Cawlfield, C; Eisenstein, B I; Karliner, I; Kim, D; Lowrey, N; Naik, P; Sedlack, C; Selen, M; White, E J; Wiss, J; Shepherd, M R; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Gong, D T; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Poling, R; Scott, A W; Smith, A; Zweber, P; Dobbs, S; Metreveli, Z V; Seth, K K; Tomaradze, A G; Ernst, J; Severini, H; al, et

    2006-01-01

    We present a measurement of the branching fraction for the doubly-Cabibbo-suppressed decay D+ to K+ pi0, using 281 pb-1 of data accumulated with the CLEO-c detector on the psi(3770) resonance. We find B(D+ to K+ pi0) = (2.28 +- 0.36 +- 0.15 +- 0.08) times 10^{-4}, where the first uncertainty is statistical, the second is systematic, and the last error is due to the uncertainty in the reference mode branching fraction.

  7. Measurements of the Branching Fraction and Time-Dependent CP Asymmetries of B0 to J/Psi pi0 Decays

    Energy Technology Data Exchange (ETDEWEB)

    George, K

    2006-03-10

    We present measurements of the branching fraction and time-dependent CP asymmetries in B{sup 0} {yields} J/{psi}{pi}{sup 0} decays based on (231.8 {+-} 2.6) x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the SLAC PEP-II asymmetric-energy B factory. We obtain a branching fraction {Beta}(B{sup 0} {yields} J/{psi}{pi}{sup 0}) = (1.94 {+-} 0.22 (stat) {+-} 0.17 (syst)) x 10{sup -5}. We also measure the CP asymmetry parameters C = -0.21 {+-} 0.26 (stat) {+-} 0.06 (syst) and S = -0.68 {+-} 0.30 (stat) {+-} 0.04 (syst).

  8. Measurements of the Branching Fraction and Time-Dependent CP Asymmetries of B0 to J/Psi pi0 Decays.

    Energy Technology Data Exchange (ETDEWEB)

    Aubert, B.

    2005-08-04

    The authors present measurements of the branching fraction and time-dependent CP asymmetries in B{sup 0} {yields} J/{psi} {pi}{sup 0} decays based on (231.8 {+-} 2.6) x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC during the years 1999-2004. We obtain a branching fraction {Beta}(B{sup 0} {yields} J/{psi}{pi}{sup 0}) = (1.94 {+-} 0.22 (stat) {+-} 0.17 (syst)) x 10{sup -5}. They also measure the CP asymmetry parameters C = -0.21 {+-} 0.26 (stat) {+-} 0.09 (syst) and S = -0.68 {+-} 0.30 (stat) {+-} 0.04 (syst). All results presented in this paper are preliminary.

  9. Weak decays and double beta decay. Annual progress report, January 1, 1982-December 31, 1982

    International Nuclear Information System (INIS)

    Work has continued in collaboration with experimenters from Yale, Brookhaven and Pittsburgh (Brookhaven experiment 702) to measure asymmetries in the decays of polarized Σ+'s into protons and neutral pions and of polarized Σ-'s into neutrons and negative pions. A short experiment was carried out in the Brookhaven AGS A2 test beam to measure the efficiency of a cylindrical shower counter essential for measuring the asymmetry parameter in the rare decay of polarized Σ+'s into protons and gammas. An electronic controller to stabilize the magnetic field of the superconducting, polarized target magnet was also designed and built at Mount Holyoke, and it functioned extremely well during a six week May to June run. Also, the design of an experiment to search for double beta decay in Molybdenum 100 is briefly described. A group consisting of five experimenters from LBL and two from Mount Holyoke hope to make a formal proposal in September to the LBL administration to begin work on this experiment late this year and during the next calendar year

  10. A measurement of the branching ratio of K± →π±μ+μ- decays in the Hyper CP experiment

    International Nuclear Information System (INIS)

    Large samples of hyperon and kaon decays were collected with the Hyper CP spectrometer during two fixed-target runs at Fermilab. Based on an analysis of 110 million K pm decays from the 1997 data sample we present a branching ratio for K pm right arrow pi pm mu+ mu-. This is the first observation of K- right arrow pi- mu+ mu- decay

  11. Measurement of Branching Fractions in Radiative BDecays to eta K gamma and Search for B Decays to eta' K gamma

    Energy Technology Data Exchange (ETDEWEB)

    Aubert, B.

    2006-03-31

    The authors present measurements of the B {yields} {eta}K{gamma} branching fractions and upper limits for the B {yields} {eta}'K{gamma} branching fractions. For B{sup +} {yields} {eta}K{sup +}{gamma} they also measure the time-integrated charge asymmetry. The data sample, collected with the BABAR detector at the Stanford Linear Accelerator Center, represents 232 x 10{sup 6} produced B{bar B} pairs. The results for branching fractions and upper limits at 90% C.L. in units of 10{sup -6} are: {Beta}(B{sup 0} {yields} {eta}K{sup 0}{gamma}) = 11.3{sub -2.6}{sup +2.8} {+-} 0.6, {Beta}(B{sup +} {yields} {eta}K{sup +}{gamma}) = 10.0 {+-} 1.3 {+-} 0.5, {Beta}(B{sup 0} {yields} {eta}'K{sup 0}{gamma}) < 6.6, {Beta}(B{sup +} {yields} {eta}'K{sup +}{gamma}) < 4.2. The charge asymmetry in the decay B{sup +} {yields} {eta}K{sup +}{gamma} is {Alpha}{sub ch} = -0.09 {+-} 0.12 {+-} 0.01. The first errors are statistical and the second systematic.

  12. On the length of an external branch in the Beta-coalescent

    CERN Document Server

    Dhersin, Jean-Stephane; Siri-Jegousse, Arno; Yuan, Linglong

    2012-01-01

    In this paper, we consider Beta$(2-{\\alpha},{\\alpha})$ (with $1<{\\alpha}<2$) and related ${\\Lambda}$-coalescents. If $T^{(n)}$ denotes the length of an external branch of the $n$-coalescent, we prove the convergence of $n^{{\\alpha}-1}T^{(n)}$ when $n$ tends to $ \\infty $, and give the limit. To this aim, we give asymptotics for the number $\\sigma^{(n)}$ of collisions which occur in the $n$-coalescent until the end of the chosen external branch, and for the block counting process associated with the $n$-coalescent.

  13. Measurements of Branching Fractions, Rate Asymmetries, and Angular Distributions in the Rare Decays B -> Kl+l- and B -> K*l+ l-

    Energy Technology Data Exchange (ETDEWEB)

    Aubert, B.

    2006-04-07

    We present measurements of the flavor-changing neutral current decays B {yields} K{ell}{sup +}{ell}{sup -} and B {yields} K*{ell}{sup +}{ell}{sup -}, where {ell}{sup +}{ell}{sup -} is either an e{sup +}e{sup -} or {mu}{sup +}{mu}{sup -} pair. The data sample comprises 229 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II e{sup +}e{sup -} storage ring. Flavor-changing neutral current decays are highly suppressed in the Standard Model and their predicted properties could be significantly modified by new physics at the electroweak scale. We measure the branching fractions {Beta}(B {yields} K{ell}{sup +}{ell}{sup -}) = (0.34 {+-} 0.07 {+-} 0.02) x 10{sup -6}, {Beta}(B {yields} K*{ell}{sup +}{ell}{sup -}) = (0.78{sub -0.17}{sup +0.19} {+-} 0.11) x 10{sup -6}, the direct CP asymmetries of these decays, and the relative abundances of decays to electrons and muons. For two regions in {ell}{sup +}{ell}{sup -} mass, above and below m{sub J/{psi}}, we measure partial branching fractions and the forward-backward angular asymmetry of the lepton pair. In these same regions we also measure the K* longitudinal polarization in B {yields} K*{ell}{sup +}{ell}{sup -} decays. Upper limits are obtained for the lepton flavor-violating decays B {yields} Ke{mu} and B {yields} K*e{mu}. All measurements are consistent with Standard Model expectations.

  14. On the spectrum of secondary electrons emitted during nuclear $\\beta^{-}$-decay in few-electron atoms

    CERN Document Server

    Frolov, Alexei M

    2015-01-01

    Ionization of light atoms and ions during nuclear $\\beta^{-}$-decay is considered. We determine the velocity/momentum spectrum of secondary electrons emitted during nuclear $\\beta^{-}$-decay in one-electron tritium atom. The same method can be applied to describe velocity/momentum distributions of secondary electrons emitted from $\\beta^{-}$-decaying few-electron atoms and molecules.

  15. Differential branching fractions and isospin asymmetries of $B \\to K^{(*)}\\mu^+\\mu^+$ decays

    CERN Document Server

    Aaij, Roel; Adinolfi, Marco; Affolder, Anthony; Ajaltouni, Ziad; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Anderson, Jonathan; Andreassen, Rolf; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Balagura, Vladislav; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Bauer, Thomas; Bay, Aurelio; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Belogurov, Sergey; Belous, Konstantin; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bien, Alexander; Bifani, Simone; Bird, Thomas; Bizzeti, Andrea; Bjørnstad, Pål Marius; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borgia, Alessandra; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Brambach, Tobias; van den Brand, Johannes; Bressieux, Joël; Brett, David; Britsch, Markward; Britton, Thomas; Brook, Nicholas; Brown, Henry; Bursche, Albert; Busetto, Giovanni; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Callot, Olivier; Calvi, Marta; Calvo Gomez, Miriam; Camboni, Alessandro; Campana, Pierluigi; Campora Perez, Daniel; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carranza-Mejia, Hector; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Cheung, Shu-Faye; Chiapolini, Nicola; Chrzaszcz, Marcin; Ciba, Krzystof; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coca, Cornelia; Coco, Victor; Cogan, Julien; Cogneras, Eric; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombes, Matthew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Counts, Ian; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dalseno, Jeremy; David, Pascal; David, Pieter; Davis, Adam; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Silva, Weeraddana; De Simone, Patrizia; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Di Canto, Angelo; Dijkstra, Hans; Donleavy, Stephanie; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dossett, David; Dovbnya, Anatoliy; Dupertuis, Frederic; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Esen, Sevda; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farinelli, Chiara; Farry, Stephen; Ferguson, Dianne; Fernandez Albor, Victor; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fontana, Marianna; Fontanelli, Flavio; Forty, Roger; Francisco, Oscar; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; Garofoli, Justin; Garra Tico, Jordi; Garrido, Lluis; Gaspar, Clara; Gauld, Rhorry; Gavardi, Laura; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianelle, Alessio; Giani', Sebastiana; Gibson, Valerie; Giubega, Lavinia-Helena; Gligorov, Vladimir; Göbel, Carla; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gordon, Hamish; Gotti, Claudio; Grabalosa Gándara, Marc; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graziani, Giacomo; Grecu, Alexandru; Greening, Edward; Gregson, Sam; Griffith, Peter; Grillo, Lucia; Grünberg, Oliver; Gui, Bin; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hall, Samuel; Hamilton, Brian; Hampson, Thomas; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; Hartmann, Thomas; He, Jibo; Head, Timothy; Heijne, Veerle; Hennessy, Karol; Henrard, Pierre; Henry, Louis; Hernando Morata, Jose Angel; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hoballah, Mostafa; Hombach, Christoph; Hulsbergen, Wouter; Hunt, Philip; Hussain, Nazim; Hutchcroft, David; Hynds, Daniel; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jaton, Pierre; Jawahery, Abolhassan; Jezabek, Marek; Jing, Fanfan; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kaballo, Michael; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Karbach, Moritz; Kelsey, Matthew; Kenyon, Ian; Ketel, Tjeerd; Khanji, Basem; Khurewathanakul, Chitsanu; Klaver, Suzanne; Kochebina, Olga; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Korolev, Mikhail; Kozlinskiy, Alexandr; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krocker, Georg; Krokovny, Pavel; Kruse, Florian; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kurek, Krzysztof; Kvaratskheliya, Tengiz; La Thi, Viet Nga; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lambert, Dean; Lambert, Robert W; Lanciotti, Elisa; Lanfranchi, Gaia; Langenbruch, Christoph; Langhans, Benedikt; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Lefèvre, Regis; Leflat, Alexander; Lefrançois, Jacques; Leo, Sabato; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Liles, Myfanwy; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Liu, Guoming; Lohn, Stefan; Longstaff, Iain; Lopes, Jose; Lopez-March, Neus; Lowdon, Peter; Lu, Haiting; Lucchesi, Donatella; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Machefert, Frederic; Machikhiliyan, Irina V; Maciuc, Florin; Maev, Oleg; Malde, Sneha; Manca, Giulia; Mancinelli, Giampiero; Manzali, Matteo; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Märki, Raphael; Marks, Jörg; Martellotti, Giuseppe; Martens, Aurelien; Martín Sánchez, Alexandra; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massafferri, André; Matev, Rosen; Mathe, Zoltan; Matteuzzi, Clara; Mazurov, Alexander; McCann, Michael; McCarthy, James; McNab, Andrew; McNulty, Ronan; McSkelly, Ben; Meadows, Brian; Meier, Frank; Meissner, Marco; Merk, Marcel; Milanes, Diego Alejandro; Minard, Marie-Noelle; Molina Rodriguez, Josue; Monteil, Stephane; Moran, Dermot; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Moron, Jakub; Mountain, Raymond; Muheim, Franz; Müller, Katharina; Muresan, Raluca; Muster, Bastien; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Anh Duc; Nguyen, Thi-Dung; Nguyen-Mau, Chung; Nicol, Michelle; Niess, Valentin; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Novoselov, Alexey; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Oggero, Serena; Ogilvy, Stephen; Okhrimenko, Oleksandr; Oldeman, Rudolf; Onderwater, Gerco; Orlandea, Marius; Otalora Goicochea, Juan Martin; Owen, Patrick; Oyanguren, Maria Arantza; Pal, Bilas Kanti; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Panman, Jacob; Papanestis, Antonios; Pappagallo, Marco; Parkes, Christopher; Parkinson, Christopher John; Passaleva, Giovanni; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pazos Alvarez, Antonio; Pearce, Alex; Pellegrino, Antonio; Pepe Altarelli, Monica; Perazzini, Stefano; Perez Trigo, Eliseo; Perret, Pascal; Perrin-Terrin, Mathieu; Pescatore, Luca; Pesen, Erhan; Petridis, Konstantin; Petrolini, Alessandro; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pilař, Tomas; Pinci, Davide; Pistone, Alessandro; Playfer, Stephen; Plo Casasus, Maximo; Polci, Francesco; Poluektov, Anton; Polycarpo, Erica; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Potterat, Cédric; Powell, Andrew; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Rachwal, Bartolomiej; Rademacker, Jonas; Rakotomiaramanana, Barinjaka; Rama, Matteo; Rangel, Murilo; Raniuk, Iurii; Rauschmayr, Nathalie; Raven, Gerhard; Reichert, Stefanie; Reid, Matthew; dos Reis, Alberto; Ricciardi, Stefania; Richards, Alexander; Rinnert, Kurt; Rives Molina, Vincente; Roa Romero, Diego; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Perez, Pablo; Roiser, Stefan; Romanovsky, Vladimir; Romero Vidal, Antonio; Rotondo, Marcello; Rouvinet, Julien; Ruf, Thomas; Ruffini, Fabrizio; Ruiz, Hugo; Ruiz Valls, Pablo; Sabatino, Giovanni; Saborido Silva, Juan Jose; Sagidova, Naylya; Sail, Paul; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santovetti, Emanuele; Sapunov, Matvey; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Savrie, Mauro; Savrina, Darya; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Seco, Marcos; Semennikov, Alexander; Senderowska, Katarzyna; Sepp, Indrek; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shires, Alexander; Silva Coutinho, Rafael; Simi, Gabriele; Sirendi, Marek; Skidmore, Nicola; Skwarnicki, Tomasz; Smith, Anthony; Smith, Edmund; Smith, Eluned; Smith, Jackson; Smith, Mark; Snoek, Hella; Sokoloff, Michael; Soler, Paul; Soomro, Fatima; Souza, Daniel; Souza De Paula, Bruno; Spaan, Bernhard; Sparkes, Ailsa; Spinella, Franco; Spradlin, Patrick; Stagni, Federico; Stahl, Sascha; Steinkamp, Olaf; Stenyakin, Oleg; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Stroili, Roberto; Subbiah, Vijay Kartik; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Swientek, Stefan; Syropoulos, Vasileios; Szczekowski, Marek; Szczypka, Paul; Szilard, Daniela; Szumlak, Tomasz; T'Jampens, Stephane; Teklishyn, Maksym; Tellarini, Giulia; Teodorescu, Eliza; Teubert, Frederic; Thomas, Christopher; Thomas, Eric; van Tilburg, Jeroen; Tisserand, Vincent; Tobin, Mark; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Torr, Nicholas; Tournefier, Edwige; Tourneur, Stephane; Tran, Minh Tâm; Tresch, Marco; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tuning, Niels; Ubeda Garcia, Mario; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vagnoni, Vincenzo; Valenti, Giovanni; Vallier, Alexis; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vázquez Sierra, Carlos; Vecchi, Stefania; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Vesterinen, Mika; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Vilasis-Cardona, Xavier; Vollhardt, Achim; Volyanskyy, Dmytro; Voong, David; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; Voss, Helge; de Vries, Jacco; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wandernoth, Sebastian; Wang, Jianchun; Ward, David; Watson, Nigel; Webber, Adam Dane; Websdale, David; Whitehead, Mark; Wicht, Jean; Wiedner, Dirk; Wilkinson, Guy; Williams, Matthew; Williams, Mike; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wright, Simon; Wu, Suzhi; Wyllie, Kenneth; Xie, Yuehong; Xing, Zhou; Xu, Zhirui; Yang, Zhenwei; Yuan, Xuhao; Yushchenko, Oleg; Zangoli, Maria; Zavertyaev, Mikhail; Zhang, Feng; Zhang, Liming; Zhang, Wen Chao; Zhang, Yanxi; Zhelezov, Alexey; Zhokhov, Anatoly; Zhong, Liang; Zvyagin, Alexander

    2014-01-01

    The isospin asymmetries of $B \\to K\\mu^+\\mu^-$ and $B \\to K^{*}\\mu^+\\mu^-$ decays and the partial branching fractions of the $B^0 \\to K^0\\mu^+\\mu^-$, $B^+ \\to K^+\\mu^+\\mu^-$ and $B^+ \\to K^{*+}\\mu^+\\mu^-$ decays are measured as functions of the dimuon mass squared, $q^2$. The data used correspond to an integrated luminosity of 3 fb$^{-1}$ from proton-proton collisions collected with the LHCb detector at centre-of-mass energies of 7 TeV and 8 TeV in 2011 and 2012, respectively. The isospin asymmetries are both consistent with the Standard Model expectations. The three measured branching fractions, while individually consistent, all favour lower values than their respective Standard Model predictions.

  16. Measurement of the branching fraction of Ds inclusive semileptonic decay Ds+→e+X

    International Nuclear Information System (INIS)

    The absolute inclusive semileptonic branching fraction of the Ds meson has been measured based on 22.3 pb-1 of e+e- collision data collected with the Beijing Spectrometer at √ (s) =4.03GeV. At this energy, the Ds are produced in pairs: e+e-→Ds+Ds-. We reconstructed 171±21±15 Ds events in five hadronic decay modes. In the recoil system of these events, several Ds inclusive semileptonic decays were observed and the branching fraction is estimated to be B(Ds+→e+X)=(7.7-4.3-2.1+5.7+2.4)%. copyright 1997 The American Physical Society

  17. Microscopic study of muon-capture transitions in nuclei involved in double-beta-decay processes

    CERN Document Server

    Kortelainen, M

    2003-01-01

    Total and partial ordinary muon-capture (OMC) rates to 1 sup + and 2 sup - states are calculated in the framework of the proton-neutron quasiparticle random-phase approximation (pnQRPA) for several nuclei involved in double-beta-decay processes. The aim is to obtain information on intermediate states involved in double-beta-decay transitions having these nuclei as either daughter or parent nuclei. It is found that the OMC observables, just like the 2 nu beta beta-decay amplitudes, strongly depend on the particle-particle part of the proton-neutron interaction. First experiments measuring the partial OMC rates for nuclei involved in double beta decays have recently been performed.

  18. Form factors and branching ratios of the FCNC B→a1ℓ+ℓ- decays

    International Nuclear Information System (INIS)

    We analyze the semileptonic B→a1ℓ+ℓ-, ℓ=τ,μ,e transitions in the framework of the three-point QCD sum rules in the standard model. These rare decays are governed by the flavor-changing neutral current transition of b→d. Considering the quark condensate contributions, the relevant form factors as well as the branching fractions of these transitions are calculated

  19. K-shell ionisation in the positron decay branch of 64Cu

    International Nuclear Information System (INIS)

    The number of K-shell vacancies per positron has been measured for the β+ decay branch of 64Cu by using a fast triple coincidence, between the annihilation quanta and the Ni x-rays, to gate the output of a high-resolution Si(Li) detector. The result, (1.33 +- 0.11) x 10-3 vacancies per positron is compared with those of other workers. (author)

  20. Measurements of mean lifetime and branching fractions of b hadrons decaying to J/ ψ

    Science.gov (United States)

    Buskulic, D.; Decamp, D.; Goy, C.; Lees, J.-P.; Minard, M.-N.; Mours, B.; Alemany, R.; Ariztizabal, F.; Comas, P.; Crespo, J. M.; Delfino, M.; Fernandez, E.; Gaitan, V.; Garrido, Ll.; Pacheco, A.; Pascual, A.; Creanza, D.; de Palma, M.; Farilla, A.; Iaselli, G.; Maggi, G.; Maggi, M.; Natali, S.; Nuzzo, S.; Quattromini, M.; Ranieri, A.; Raso, G.; Romano, F.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Zito, G.; Hu, H.; Huang, D.; Huang, X.; Lin, J.; Lou, J.; Qiao, C.; Wang, T.; Xie, Y.; Xu, D.; Xu, R.; Zhang, J.; Zhao, W.; Atwood, W. B.; Bauerdick, L. A. T.; Blucher, E.; Bonvicini, G.; Bossi, F.; Boudreau, J.; Burnett, T. H.; Drevermann, H.; Forty, R. W.; Hagelberg, R.; Harvey, J.; Haywood, S.; Hilgart, J.; Jacobsen, R.; Jost, B.; Knobloch, J.; Lançon, E.; Lehraus, I.; Lohse, T.; Lusiani, A.; Martinez, M.; Mato, P.; Mattison, T.; Meinhard, H.; Menary, S.; Meyer, T.; Minten, A.; Miquel, R.; Moser, H.-G.; Palazzi, P.; Perlas, J. A.; Pusztaszeri, J.-F.; Ranjard, F.; Redlinger, G.; Rolandi, L.; Roth, A.; Rothberg, J.; Ruan, T.; Saich, M.; Schlatter, D.; Schmelling, M.; Sefkow, F.; Tejessy, W.; Wachsmuth, H.; Wiedenmann, W.; Wildish, T.; Witzeling, W.; Wotschack, J.; Ajaltouni, Z.; Badaud, F.; Bardadin-Otwinowska, M.; Bencheikh, A. M.; El Fellous, R.; Falvard, A.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Montret, J.-C.; Pallin, D.; Perret, P.; Pietrzyk, B.; Proriol, J.; Prulhière, F.; Stimpfl, G.; Fearnley, T.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Møllerud, R.; Nilsson, B. S.; Efthymiopoulos, I.; Kyriakis, A.; Simopoulou, E.; Vayaki, A.; Zachariadou, K.; Badier, J.; Blondel, A.; Bonneaud, G.; Brient, J. C.; Fouque, G.; Orteu, S.; Rosowsky, A.; Rougé, A.; Rumpf, M.; Tanaka, R.; Verderi, M.; Videau, H.; Candlin, D. J.; Parsons, M. I.; Veitch, E.; Moneta, L.; Parrini, G.; Corden, M.; Georgiopoulos, C.; Ikeda, M.; Lannutti, J.; Levinthal, D.; Mermikides, M.; Sawyer, L.; Wasserbaech, S.; Antonelli, A.; Baldini, R.; Bencivenni, G.; Bologna, G.; Campana, P.; Capon, G.; Cerutti, F.; Chiarella, V.; D'Ettorre-Piazzoli, B.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Passalacqua, L.; Pepe-Altarelli, M.; Picchi, P.; Altoon, B.; Boyle, O.; Colrain, P.; Ten Have, I.; Lynch, J. G.; Maitland, W.; Morton, W. T.; Raine, C.; Scarr, J. M.; Smith, K.; Thompson, A. S.; Turnbull, R. M.; Brandl, B.; Braun, O.; Geiges, R.; Geweniger, C.; Hanke, P.; Hepp, V.; Kluge, E. E.; Maumary, Y.; Putzer, A.; Rensch, B.; Stahl, A.; Tittel, K.; Wunsch, M.; Belk, A. T.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Cattaneo, M.; Colling, D. J.; Dornan, P. J.; Dugeay, S.; Greene, A. M.; Hassard, J. F.; Lieske, N. M.; Nash, J.; Patton, S. J.; Payne, D. G.; Phillips, M. J.; Sedgbeer, J. K.; Tomalin, I. R.; Wright, A. G.; Kneringer, E.; Kuhn, D.; Rudolph, G.; Bowdery, C. K.; Brodbeck, T. J.; Finch, A. J.; Foster, F.; Hughes, G.; Jackson, D.; Keemer, N. R.; Nuttall, M.; Patel, A.; Sloan, T.; Snow, S. W.; Whelan, E. P.; Kleinknecht, K.; Raab, J.; Renk, B.; Sander, H.-G.; Schmidt, H.; Steeg, F.; Walther, S. M.; Wolf, B.; Aubert, J.-J.; Benchouk, C.; Bernard, V.; Bonissent, A.; Carr, J.; Coyle, P.; Drinkard, J.; Etienne, F.; Papalexiou, S.; Payre, P.; Qian, Z.; Rousseau, D.; Schwemling, P.; Talby, M.; Adlung, S.; Bauer, C.; Blum, W.; Brown, D.; Cowan, G.; Dehning, B.; Dietl, H.; Dydak, F.; Fernandez-Bosman, M.; Frank, M.; Halley, A. W.; Hauber, J.; Lütjens, G.; Lutz, G.; Männer, W.; Richter, R.; Rotscheidt, H.; Schröder, J.; Schwarz, A. S.; Settles, R.; Seywerd, H.; Stierlin, U.; Stiegler, U.; Denis, R. St.; Takashima, M.; Thomas, J.; Wolf, G.; Bertin, V.; Boucrot, J.; Callot, O.; Chen, X.; Cordier, A.; Davier, M.; Grivaz, J.-F.; Heusse, Ph.; Janot, P.; Kim, D. W.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Schune, M.-H.; Veillet, J.-J.; Videau, I.; Zhang, Z.; Zomer, F.; Abbaneo, D.; Amendolia, S. R.; Bagliesi, G.; Batignani, G.; Bosisio, L.; Bottigli, U.; Bradaschia, C.; Carpinelli, M.; Ciocci, M. A.; Dell'Orso, R.; Ferrante, I.; Fidecaro, F.; Foà, L.; Focardi, E.; Forti, F.; Giassi, A.; Giorgi, M. A.; Ligabue, F.; Mannelli, E. B.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Rizzo, G.; Sanguinetti, G.; Spagnolo, P.; Steinberger, J.; Tenchini, R.; Tonelli, G.; Triggiani, G.; Vannini, C.; Venturi, A.; Verdini, P. G.; Walsh, J.; Carter, J. M.; Green, M. G.; March, P. V.; Mir, Ll. M.; Medcalf, T.; Quazi, I. S.; Strong, J. A.; West, L. R.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Edwards, M.; Fisher, S. M.; Jones, T. J.; Norton, P. R.; Salmon, D. P.; Thompson, J. C.; Bloch-Devaux, B.; Colas, P.; Duarte, H.; Kozanecki, W.; Lemaire, M. C.; Locci, E.; Loucatos, S.; Monnier, E.; Perez, P.; Perrier, F.; Rander, J.; Renardy, J.-F.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Si Mohand, D.; Vallage, B.; Johnson, R. P.; Litke, A. M.; Taylor, G.; Wear, J.; Ashman, J. G.; Babbage, W.; Booth, C. N.; Buttar, C.; Carney, R. E.; Cartwright, S.; Combley, F.; Hatfield, F.; Reeves, P.; Thompson, L. F.; Barberio, E.; Böhrer, A.; Brandt, S.; Grupen, C.; Mirabito, L.; Rivera, F.; Schäfer, U.; Ganis, G.; Giannini, G.; Gobbo, B.; Ragusa, F.; Bellantoni, L.; Chen, W.; Cinabro, D.; Conway, J. S.; Cowen, D. F.; Feng, Z.; Ferguson, D. P. S.; Gao, Y. S.; Grahl, J.; Harton, J. L.; Jared, R. C.; Leclaire, B. W.; Lishka, C.; Pan, Y. B.; Peter, J. R.; Saadi, Y.; Sharma, V.; Schmitt, M.; Shi, Z. H.; Walsh, A. M.; Weber, F. V.; Whitney, M. H.; Sau Lan Wu; Wu, X.; Zoberning, G.; Aleph Collaboration

    1992-12-01

    From a data sample of 450 000 hadronic events recorded with the ALEPH detector at LEP, 92±10 events are observed containing a J/ψ meson decaying to μ+μ- or e +e -. From these data the measured inclusive branching fraction for a b flavoured hadron to decay to a J/ψ is BR(b→ J/ ψX) = (1.21±0.13 (stat.)±0.08 (syst.))%, and the average b hadron lifetime in the events tagged with a J/ ψ is τb = 1.35 +0.19-0.17±0.05 ps. Five events are observed consistent with the exclusive decay B ± → J/ ψK ± and from these events the exclusive branching fraction is measured to be BR(B ± → J/ ψK ±) = (0.22±0.10±0.02)%. Upper limits for other exclusive branching ratios are given.

  1. The Gerda search for neutrinoless double beta decay

    Science.gov (United States)

    O'Shaughnessy, Christopher; Gerda Collaboration

    2013-10-01

    The Germanium Detector Array (Gerda) is a search for the neutrinoless double beta decay of 76Ge. High Purity Germanium (HPGe) detectors enriched in the isotope-76 are operated bare in liquid argon (LAr). LAr is used for both cooling of the HPGe diodes to their operating temperatures and for shielding from external radiation sources. From the measurements of the first phase that began data taking on 1 Nov. 2011 it is expected to have a sensitivity on the level of T1/2>2E25 yr at a 90% CL after 15 kġyr. The goal of this phase will be to probe the claim of an observation by part of the Heidelberg-Moscow collaboration. Efforts will then focus on increasing the sensitivity of the experiment by deploying additional enriched detectors that are in an advanced stage of production and by reducing the background index further by making use of pulse shape discrimination techniques as well as an active LAr veto. While the 0νββ region of interest continues to remain blinded, here the status of Phase-I data taking is presented along with the work towards improving the experimental sensitivity.

  2. Theoretical and Experimental Considerations for Neutrinoless Double Beta Decay

    CERN Document Server

    Castillo, O; Grosse-Oetringhaus, J F; Lenzi, B; Panes, B; Tibbetts, M; Valenzuela, C; Yacoob, S; Yagues, A G; Zanetti, C

    2008-01-01

    In the rst part of this work we show some theoretical aspects of the generation of the neutrino mass by means of a direct extension of the Standard Model of particles, which include the presence of heavy right-handed neutrinos and large Majorana mass terms. From these two new ingredients, it is possible to nd a mass for the light neutrinos which is naturally of the order of 1 eV or less. The idea is to put these theoretical aspects in the context of the search for neutrino mass values by the study of the signal from the Neutrinoless Double Beta Decay Process (0 ). In the second part, a brief summary is given of the experimental considerations required for the measurement of effective Majorana neutrino mass using (0 ). Measurement strategies and background considerations are introduced and an outline of both active and passive methods is given. Finally, current results are discussed with particular emphasis on the Heidelberg–Moscow experiment. This note is based on the presentation given at the CERN–CLAF 4th...

  3. Tritium $\\beta$-decay in chiral effective field theory

    CERN Document Server

    Baroni, A; Kievsky, A; Marcucci, L E; Schiavilla, R; Viviani, M

    2016-01-01

    We evaluate the Fermi and Gamow-Teller (GT) matrix elements in tritium \\beta-decay by including in the charge-changing weak current the corrections up to one loop recently derived in nuclear chiral effective field theory (\\chi EFT). The trinucleon wave functions are obtained from hyperspherical-harmonics solutions of the Schrodinger equation with two- and three-nucleon potentials corresponding to either \\chi EFT (the N3LO/N2LO combination) or meson-exchange phenomenology (the AV18/UIX combination). We find that contributions due to loop corrections in the axial current are, in relative terms, as large as (and in some cases, dominate) those from one-pion exchange, which nominally occur at lower order in the power counting. We also provide values for the low-energy constants multiplying the contact axial current and three-nucleon potential, required to reproduce the experimental GT matrix element and trinucleon binding energies in the N3LO/N2LO and AV18/UIX calculations.

  4. LUCIFER: scintillating bolometers for neutrinoless double-beta decay searches

    Science.gov (United States)

    Pattavina, Luca

    2014-09-01

    In the field of fundamental particle physics, the nature of the neutrino, if it is a Dirac or a Majorana particle, plays a crucial role not only in neutrino physics, but also in the overall framework of fundamental particle interactions and in cosmology. Neutrinoless double-beta decay (0vDBD) is the key tool for the investigation of this nature. Experimental techniques based on the calorimetric approach with cryogenic particle detectors have demonstrated suitability for the investigation of rare nuclear processes, profiting from excellent energy resolution and scalability to large masses. Unfortunately, the most relevant issue is related to background suppression. In fact, bolometers being fully-active detectors struggle to reach extremely low background level. The LUCIFER project aims to deploy the first array of enriched scintillating bolometers. Thanks to the double read-out - heat and scintillation light produced by scintillating bolometers - a highly efficient background identification and rejection is guaranteed, leading to a background-free experiment. We show the potential of such technology in ZnMoO4 and ZnSe prototypes. We describe the current status of the project, including results of the recent R&D activity.

  5. Beta decay studies of r-process nuclei at the National Superconducting Cyclotron Laboratory

    CERN Document Server

    Pereira, J; Arndt, O; Becerril, A; Elliot, T; Estrade, A; Galaviz, D; Hennrich, S; Hosmer, P; Kessler, R; Kratz, K L; Lorusso, G; Mantica, P F; Matos, M; Montes, F; Santi, P; Pfeiffer, B; Quinn, M; Schatz, H; Schertz, F; Schnorrenberger, L; Smith, E; Tomlin, B E; Walters, W; Wöhr, A

    2009-01-01

    The impact of nuclear physics on astrophysical r-process models is discussed, emphasizing the importance of beta-decay properties of neutron-rich nuclei. Several r-process motivated beta-decay experiments performed at the National Superconducting Cyclotron Laboratory are presented. The experiments include the measurement of beta-decay half-lives and neutron emission probabilities of nuclei in regions around Ni-78; Se-90; Zr-106 and Rh-120, as well as spectroscopic studies of Pd-120. A summary on the different experimental techniques employed, data analysis, results and impact on model calculations is presented.

  6. Getting Information on |Ue3|2 from Neutrinoless Double Beta Decay

    Directory of Open Access Journals (Sweden)

    Alexander Merle

    2007-01-01

    neutrinoless double beta decay. We show that typically a lower limit on |Ue3| as a function of the smallest neutrino mass can be set. Furthermore, we give the values of the sum of neutrino masses and |Ue3| which are allowed and forbidden by an experimental upper limit on the effective mass. Alternative explanations for neutrinoless double beta decay, Dirac neutrinos or unexplained cosmological features would be required if future measurements showed that the values lie in the respective regions. Moreover, we show that a measurement of |Ue3| from neutrinoless double beta decay is very difficult due to the expected errors on the effective mass and the oscillation parameters.

  7. Stable continuous branching processes with immigration and Beta-Fleming-Viot processes with immigration

    CERN Document Server

    Foucart, Clément

    2012-01-01

    Branching processes and Fleming-Viot processes are two main models in stochastic population theory. Incorporating an immigration in both models, we generalize the results of Shiga (1990) and Birkner et al. (2005) which respectively connect the Feller diffusion with the classical Fleming-Viot process and the alpha-stable continuous state branching process with the Beta(2-alpha, alpha)-generalized Fleming-Viot process. In a recent work, a new class of probability-measure valued processes, called M-generalized Fleming-Viot processes with immigration, has been set up in duality with the so-called M-coalescents. The purpose of this article is to investigate the links between this new class of processes and the continuous-state branching processes with immigration. In the specific case of the $\\alpha$-stable branching process conditioned to be never extinct, we get that its genealogy is given, up to a random time change, by a Beta(2-alpha, alpha-1)-coalescent.

  8. Test of the single state dominance hypothesis for the two-neutrino double beta decay

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, O; Alvarez-Rodriguez, R; Moya de Guerra, E [Dpto. Fisica Atom., Mol. y Nuclear, University Complutense de Madrid, E-28040 Madrid (Spain); Sarriguren, P [Instituto de Estructura de la Materia, CSIC, Serrano 123, E-28006 Madrid (Spain); Simkovic, F [Department of Nuclear Physics, Comenius University, SK-842 15 Bratislava (Slovakia); Faessler, Amand, E-mail: oscar.moreno@iem.cfmac.csic.e [Institut fuer Theoretische Physik, Universitaet Tuebingen, D-72076 Tuebingen (Germany)

    2010-01-01

    The single state dominance hypothesis for the two-neutrino double-beta decay matrix elements is tested in this work for the double-beta decaying nuclei {sup 100}Mo, {sup 116}Cd, and {sup 128}Te. In addition to this, we analyze the contribution to the double-beta matrix elements from the low-lying intermediate states and from the whole set of intermediate states. We use a proton-neutron QRPA calculation based on a deformed Skyrme Hartree-Fock mean field with pairing correlations, and we compare these results with the half-lives of the double-beta emitters for which we have experimental information.

  9. Branching ratio and CP asymmetry of Bs→π+π- decays in the perturbative QCD approach

    International Nuclear Information System (INIS)

    In this paper, we calculate the decay rate and CP asymmetry of the Bs→π+π- decay in the perturbative QCD approach with Sudakov resummation. Since none of the quarks in final states is the same as those of the initial Bs meson, this decay can occur only via annihilation diagrams in the standard model. Besides the current-current operators, the contributions from the QCD and electroweak penguin operators are also taken into account. We find that (a) the branching ratio is about 4x10-7; (b) the penguin diagrams dominate the total contribution; and (c) the direct CP asymmetry is small in size: no more than 3%; but the mixing-induced CP asymmetry can be as large as 10% testable in the near future LHC-b experiments

  10. Beta decay of fission products for the non-proliferation and decay heat of nuclear reactors

    International Nuclear Information System (INIS)

    issue of nuclear safety. In this thesis, we present an experimental work which aims to measure the properties of beta decay of fission products important to the non-proliferation and reactor decay heat. First steps using the technique of Total Absorption Gamma-ray Spectroscopy (TAGS) were carried on at the radioactive beam facility of the University of Jyvaskyla. We will present the technique used, the experimental setup and part of the analysis of this experiment. (author)

  11. Search for $\\beta^+$EC and ECEC processes in $^{112}$Sn and $\\beta^-\\beta^-$ decay of $^{124}$Sn to the excited states of $^{124}$Te

    CERN Document Server

    Barabash, A S; Nachab, A; Konovalov, S I; Vanyushin, I A; Umatov, V I

    2008-01-01

    Limits on $\\beta^+$EC and ECEC processes in $^{112}$Sn and on $\\beta^-\\beta^-$ decay of $^{124}$Sn to the excited states of $^{124}$Te have been obtained using a 380 cm$^3$ HPGe detector and an external source consisting of natural tin. A limit with 90% C.L. on the $^{112}$Sn half-life of $0.92\\times 10^{20}$ y for the ECEC(0$\

  12. Evidence for the Rare Decay B -> K*(ell) sup + (ell) sup - land Measurement of the B -> K(ell) sup + (ell) sup - Branching Fraction

    CERN Document Server

    Berryhill, J W

    2003-01-01

    We present evidence for the flavor-changing neutral current decay B -> K*(ell) sup + (ell) sup - and a measurement of the branching fraction for the related process B -> K(ell) sup + (ell) sup - , where (ell) sup + (ell) sup - is either an e sup + e sup - or mu sup +mu sup - pair. These decays are highly suppressed in the Standard Model, and they are sensitive to contributions from new particles in the intermediate state. The data sample comprises 123 x 10 sup 6 UPSILON(4S) -> B(bar B) decays collected with the BABAR detector at the PEP-II e sup + e sup - storage ring. Averaging over K* isospin and lepton flavor, we obtain the branching fractions BETA(B -> K(ell) sup + (ell) sup -) = (0.65 sub - sub 0 sub . sub 1 sub 3 sup + sup 0 sup . sup 1 sup 4 +- 0.04) x 10 sup - sup 6 BETA(B -> K*(ell) sup + (ell) sup -) = (0.88 sub - sub 0 sub . sub 2 sub 9 sup + sup 0 sup . sup 3 sup 3 +- 0.10) x 10 sup - sup 6 , where the uncertainties are statistical and systematic, respectively. The significance of the B -> K(ell) ...

  13. Study of Rare B-Meson Decays Related to the CPObservable sin(2beta+gamma) at the BABAR Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Orimoto, Toyoko Jennifer

    2007-08-21

    This study reports the observation of the decays B{sup 0}{yields}D{sup (*)+}{sub S}{pi}{sup -} and B{sup 0}{yields}D{sup (*)-}K{sup +} in a sample of 230 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} events collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} storage ring, located at the Stanford Linear Accelerator Center. The branching fractions {beta}(B{sup 0} {yields} D{sup +}{sub S}{pi}{sup -}) = (1.3 {+-} 0.3 (stat) {+-} 0.2 (syst)) x 10{sup -5}, {beta}(B{sup 0} {yields} D{sup +}{sub S}K{sup +}) = (2.5 {+-} 0.4 (stat) {+-} 0.4 (syst)) x 10{sup -5}, {beta}(B{sup 0}{yields}D{sup (*)+}{sub S}{pi}{sup -}) = (2.8 {+-} 0.6 (stat) {+-} 0.5 (syst)) x 10{sup -5}, and {beta}(B{sup 0}{yields}D{sup (*)-}K{sup +}) = (2.0 {+-} 0.5 (stat) {+-} 0.4 (syst)) x 10{sup -5} are measured. The significance of the measurements to differ from zero are 5, 9, 6, and 5 standard deviations, respectively. This is a first observation of the decaysB{sup 0}{yields}D{sup (*)+}{sub S}{pi}{sup -} and B{sup 0}{yields}D{sup (*)-}K{sup +}. These results may potentially be useful in determining the CP asymmetry parameter sin(2{beta} + {gamma}) in the decays B{sup 0}{yields}D{sup (*)+}{sub S}{pi}{sup -}.

  14. Analysis of super-allowed Fermi beta-decay

    International Nuclear Information System (INIS)

    Analysis of tile Jπ = 0+ → 0+ super-allowed Fermi transitions within isospin triplets is limited in the precision of its outcome not by the accuracy of the experimental input data nor by the confidence with which the radiative corrections can be applied but by knowledge of the nuclear mismatch: the subversion of the isospin symmetry along the multiplets by the charge-dependence of the forces, both Coulomb and specifically nuclear. Theoretical estimates of the mismatch differ considerably from author to author, their direct application results in clear violation of tile hypothesis of conservation of the vector current and clear inconsistency with unitarity of the Cabibbo-Kobayashi-Maskawa matrix. This paper pursues and elaborates the previous suggestion that, in these unsatisfactory circumstances, the best procedure is to look to the experimental data themselves to determine and eliminate the mismatch by appropriate extrapolation to Z=O. This is done: (i) without any prior correction for mismatch; (ii) after correction for the full theoretical mismatch; (iii) after correction for case-to-case fluctuations in the theoretical mismatch. These three procedures are individually statistically satisfactory and mutually consistent in their extrapolation to Z = 0 despite the variety of the theoretical mismatches on which, in varying degrees, they are based. The resultant unitarity test for the CKM matrix is IVudI2 + IVusI2 + IVubI2 = 1.0003 ± 0.0014. The associated value for the operational vector coupling constant is: Gv* / (hc)3 = (1.15155±0.00064) x 10-5 GeV-2. If unitarity of the CKM matrix is alternatively assumed one may conclude, from a similar analysis, that the mean charge of the fermionic fields between which beta-decay takes place is Q-bar = 0.172±0.060 and that, at the 90% confidence level, bF -3 were bF is the relative effective scalar coupling constant. Neutron decay is also discussed, with the provisional recommendations: GA*/(hc)3 (1.4557±0.0051) x 10

  15. GERDA: a germanium detector array to search for neutrinoless double beta decay

    International Nuclear Information System (INIS)

    The GERDA, a new experiment to search for the double beta decay of 76Ge, is being installed at Laboratori Nazionali del Gran Sasso. The potentialities of this experiment as well the status of the project are reviewed

  16. First results of neutrinoless double beta decay search with the GERmanium Detector Array "GERDA"

    Science.gov (United States)

    Janicskó Csáthy, József

    2014-06-01

    The study of neutrinoless double beta decay is the most powerful approach to the fundamental question if the neutrino is a Majorana particle, i.e. its own anti-particle. The observation of the lepton number violating neutrinoless double beta decay would establish the Majorana nature of the neutrino. Until now neutrinoless double beta decay was not observed. The GERmanium Detector Array, GERDA is a double beta decay experiment located at the INFN Gran Sasso National Laboratory, Italy. GERDA operates bare Ge diodes enriched in 76Ge in liquid argon supplemented by a water shield. The exposure accumulated adds up to 21.6 kg· yr with a background level of 1.8 · 10-2 cts/(keV·kg·yr). The results of the Phase I of the experiment are presented and the preparation of the Phase II is briefly discussed.

  17. Beta decay of 252Cf on the way to scission from the exit point

    CERN Document Server

    Pomorski, K; Quentin, P

    2015-01-01

    Upon increasing significantly the nuclear elongation, the beta-decay energy grows. This paper investigates within a simple yet partly microscopic approach, the transition rate of the beta decay of the 252Cf nucleus on the way to scission from the exit point for a spontaneous fission process. A rather crude classical approximation is made for the corresponding damped collective motion assumed to be one dimensional. Given these assumptions, we only aim in this paper at providing the order of magnitudes of such a phenomenon. At each deformation the energy available for beta decay, is determined from such a dynamical treatment. Then, for a given elongation, transition rates for the allowed (Fermi) beta decay are calculated from pair correlated wave functions obtained within a macroscopic-microscopic approach and then integrated over the time corresponding to the whole descent from exit to scission. The results are presented as a function of the damping factor (inverse of the characteristic damping time) in use in...

  18. Results on $\\beta\\beta$ decay with emission of two neutrinos or Majorons in $^{76}$Ge from GERDA Phase I

    CERN Document Server

    Agostini, M; Bakalyarov, A M; Balata, M; Barabanov, I; Barros, N; Baudis, L; Bauer, C; Becerici-Schmidt, N; Bellotti, E; Belogurov, S; Belyaev, S T; Benato, G; Bettini, A; Bezrukov, L; Bode, T; Borowicz, D; Brudanin, V; Brugnera, R; Budjáš, D; Caldwell, A; Cattadori, C; Chernogorov, A; D'Andrea, V; Demidova, E V; di Vacri, A; Domula, A; Doroshkevich, E; Egorov, V; Falkenstein, R; Fedorova, O; Freund, K; Frodyma, N; Gangapshev, A; Garfagnini, A; Grabmayr, P; Gurentsov, V; Gusev, K; Hegai, A; Heisel, M; Hemmer, S; Heusser, G; Hofmann, W; Hult, M; Inzhechik, L V; Csáthy, J Janicskó; Jochum, J; Junker, M; Kazalov, V; Kihm, T; Kirpichnikov, I V; Kirsch, A; Klimenko, A; Knöpfle, K T; Kochetov, O; Kornoukhov, V N; Kuzminov, V V; Laubenstein, M; Lazzaro, A; Lebedev, V I; Lehnert, B; Liao, H Y; Lindner, M; Lippi, I; Lubashevskiy, A; Lubsandorzhiev, B; Lutter, G; Macolino, C; Majorovits, B; Maneschg, W; Medinaceli, E; Misiaszek, M; Moseev, P; Nemchenok, I; Palioselitis, D; Panas, K; Pandola, L; Pelczar, K; Pullia, A; Riboldi, S; Rumyantseva, N; Sada, C; Salathe, M; Schmitt, C; Schreiner, J; Schulz, O; Schwingenheuer, B; Schönert, S; Selivanenko, O; Shirchenko, M; Simgen, H; Smolnikov, A; Stanco, L; Stepaniuk, M; Ur, C A; Vanhoefer, L; Vasenko, A A; Veresnikova, A; von Sturm, K; Wagner, V; Walter, M; Wegmann, A; Wester, T; Wilsenach, H; Wojcik, M; Yanovich, E; Zavarise, P; Zhitnikov, I; Zhukov, S V; Zinatulina, D; Zuber, K; Zuzel, G

    2015-01-01

    A search for neutrinoless $\\beta\\beta$ decay processes accompanied with Majoron emission has been performed using data collected during Phase I of the GERmanium Detector Array (GERDA) experiment at the Laboratori Nazionali del Gran Sasso of INFN (Italy). Processes with spectral indices n = 1, 2, 3, 7 were searched for. No signals were found and lower limits of the order of 10$^{23}$ yr on their half-lives were derived, yielding substantially improved results compared to previous experiments with $^{76}$Ge. A new result for the half-life of the neutrino-accompanied $\\beta\\beta$ decay of $^{76}$Ge with significantly reduced uncertainties is also given, resulting in $T^{2\

  19. Detection System for Neutron $\\beta$ Decay Correlations in the UCNB and Nab experiments

    CERN Document Server

    Broussard, L J; Adamek, E R; Baeßler, S; Birge, N; Blatnik, M; Bowman, J D; Brandt, A E; Brown, M; Burkhart, J; Callahan, N B; Clayton, S M; Crawford, C; Cude-Woods, C; Currie, S; Dees, E B; Ding, X; Fomin, N; Frlez, E; Fry, J; Gray, F E; Hasan, S; Hickerson, K P; Hoagland, J; Holley, A T; Ito, T M; Klein, A; Li, H; Liu, C -Y; Makela, M F; McGaughey, P L; Mirabal-Martinez, J; Morris, C L; Ortiz, J D; Pattie, R W; Penttilä, S I; Plaster, B; Počanić, D; Ramsey, J C; Salas-Bacci, A; Salvat, D J; Saunders, A; Seestrom, S J; Sjue, S K L; Sprow, A P; Tang, Z; Vogelaar, R B; Vorndick, B; Wang, Z; Wei, W; Wexler, J; Wilburn, W S; Womack, T L; Young, A R

    2016-01-01

    We describe a detection system designed for precise measurements of angular correlations in neutron $\\beta$ decay. The system is based on thick, large area, highly segmented silicon detectors developed in collaboration with Micron Semiconductor, Ltd. The prototype system meets specifications for $\\beta$ electron detection with energy thresholds below 10 keV, energy resolution of $\\sim$3 keV FWHM, and rise time of $\\sim$50 ns with 19 of the 127 detector pixels instrumented. Using ultracold neutrons at the Los Alamos Neutron Science Center, we have demonstrated the coincident detection of $\\beta$ particles and recoil protons from neutron $\\beta$ decay. The fully instrumented detection system will be implemented in the UCNB and Nab experiments, to determine the neutron $\\beta$ decay parameters $B$, $a$, and $b$.

  20. Bond Rupture following C14 and T3 Beta Decay

    International Nuclear Information System (INIS)

    As a result of nuclear transformations an atom acquires a recoil energy, and a portion of this energy becomes associated with the chemical bond or bonds joining the activated atom to the molecule. Usually sufficient energy is deposited in these bonds to permit the activated atom to dissociate from the remainder of the molecule. Bond-rupture, however, usually does not occur with 100% efficiency. Momentum transfer to an atom in a molecule (internal excitation and bond-rupture) have been discussed recently with reference to activation of atoms joined to a molecule by only one bond. Additional molecules are considered in the present paper, and data presented on the net recoil energy required for bond- rupture, the rotational and vibrational excitation energies received by the rupturing bond, the internal energy of the radical originally bonded to the activated atom, and the kinetic energy of the radicals. It is shown that, on the average, the recoil energy that must be acquired by the activated atom in order to rupture from the molecule is about 25% greater than that calculated assuming a pseudo-diatomic molecule. Data are also presented for certain C14 and T3 beta-decay recoil processes. For C14O2 it is calculated that a net N14 recoil energy s 1.92 times the ON-O+ bond dissociation energy is required for bond-rupture. Since the NO+2 product may possess about 0.6 to 1.0 eV of electronic excitation energy, the ON-O+ bond dissociation energy is not uniquely defined. The calculated value of non-bond-rupture is 73 - 87% in good agreement with the reported experimental value of 81%. Similar data are also presented for such molecules as CH3T, C2H5T, C3H7T, and C142H6. (author)

  1. Sense and sensitivity of double beta decay experiments

    International Nuclear Information System (INIS)

    The search for neutrinoless double beta decay is a very active field in which the number of proposals for next-generation experiments has proliferated. In this paper we attempt to address both the sense and the sensitivity of such proposals. Sensitivity comes first, by means of proposing a simple and unambiguous statistical recipe to derive the sensitivity to a putative Majorana neutrino mass, mββ. In order to make sense of how the different experimental approaches compare, we apply this recipe to a selection of proposals, comparing the resulting sensitivities. We also propose a ''physics-motivated range'' (PMR) of the nuclear matrix elements as a unifying criterium between the different nuclear models. The expected performance of the proposals is parametrized in terms of only four numbers: energy resolution, background rate (per unit time, isotope mass and energy), detection efficiency, and ββ isotope mass. For each proposal, both a reference and an optimistic scenario for the experimental performance are studied. In the reference scenario we find that all the proposals will be able to partially explore the degenerate spectrum, without fully covering it, although four of them (KamLAND-Zen, CUORE, NEXT and EXO) will approach the 50 meV boundary. In the optimistic scenario, we find that CUORE and the xenon-based proposals (KamLAND-Zen, EXO and NEXT) will explore a significant fraction of the inverse hierarchy, with NEXT covering it almost fully. For the long term future, we argue that 136Xe-based experiments may provide the best case for a 1-ton scale experiment, given the potentially very low backgrounds achievable and the expected scalability to large isotope masses

  2. Weak-interaction and nuclear-structure aspects of nuclear double beta decay

    International Nuclear Information System (INIS)

    Weak-interaction and nuclear-structure aspects of double beta decay are reviewed. Starting from effective electroweak lagrangians, decay rates for the two-neutrino and neutrinoless modes of the nuclear double beta decay transitions are defined and second-order perturbative expressions for the nuclear decay amplitudes are given. Nuclear matrix elements of the relevant operators are presented, as extracted from data and from shell-model and QRPA calculations as well as from other theoretical approximations. The analysis is performed both for the two-neutrino and neutrinoless modes of the decay. The expressions for ground-state-to-ground-state and ground-state-to-excited-state transitions are presented. Updated experimental and theoretical information on β-β- decays in 48Ca, 76Ge, 82Se, 96Zr, 100Mo, 116Cd, 124Sn, 128Te, 130Te, 136Xe, 150Nd, and on β+β+, β+ EC and double EC decays in 78Kr, 92Mo, 96Ru, 106Cd, 124Xe, 130Ba, 136Ce is analyzed and compared with theoretical results. The relevance of single-beta-decay transitions feeding some of the nuclei where double-beta-decay transitions occur is pointed out. The systematics of various phase-space factors and extracted matrix elements is presented. (orig.)

  3. Measurements of D0 production and of decay branching fractions in neutrino-nucleon scattering

    International Nuclear Information System (INIS)

    During the years 1994-1997, the emulsion target of the CHORUS detector was exposed to the wide-band neutrino beam of the CERN SPS of 27 GeV average neutrino energy. In total about 100-bar 000 charged-current neutrino interactions were located in the nuclear emulsion target and fully reconstructed. From this sample of events which was based on the data acquired by new automatic scanning systems, 1048 charged-current interactions with a D0 in the final state were selected by a pattern recognition program and confirmed as neutral-particle decays through visual inspection. The ratio of decay branching fractions of the D0 into four charged particles to two charged particles was measured to be B(D0->V4)/B(D0->V2)=0.207+/-0.016+/-0.004. The inclusive measurement of the observed production rate of the D0 with a decay into four charged prongs in combination with external measurements of this topological branching ratio was used to determine the total D0 production rate by neutrinos without additional assumption on the branching fractions. The value of this rate relative to the charged-current cross-section was found to be σ(D0)/σ(CC)=0.0269+/-0.0018+/-0.0013. In addition, the same normalization method was used to deduce the inclusive topological decay rate into final states with neutral particles only. A value of 0.218+/-0.049+/-0.036 was found for this branching fraction. From an observed number of three charged six-prong events the branching ratio into six charged particles was determined to be (1.2-0.9+1.3+/-0.2)x10-3. A measurement of the energy dependence of the D0 production by neutrinos relative to the total charged-current cross-section is also reported. This measurement was used to deduce for mc, the effective charm-quark mass, a value of (1.42+/-0.08)GeV/c2

  4. Search for Neutrinoless Double-Beta Decay in $^{136}$Xe with EXO-200

    CERN Document Server

    Auger, M; Barbeau, P S; Beauchamp, E; Belov, V; Benitez-Medina, C; Breidenbach, M; Brunner, T; Burenkov, A; Cleveland, B; Cook, S; Daniels, T; Danilov, M; Davis, C G; Delaquis, S; deVoe, R; Dobi, A; Dolinski, M J; Dolgolenko, A; Dunford, M; Fairbank, W; Farine, J; Feldmeier, W; Fierlinger, P; Franco, D; Giroux, G; Gornea, R; Graham, K; Gratta, G; Hall, C; Hall, K; Hargrove, C; Herrin, S; Hughes, M; Johnson, A; Johnson, T N; Karelin, A; Kaufman, L J; Kuchenkov, A; Kumar, K S; Leonard, D S; Leonard, F; Mackay, D; MacLellan, R; Marino, M; Mong, B; Diez, M Montero; Muller, A R; Neilson, R; Nelson, R; Odian, A; Ostrovskiy, I; O'Sullivan, K; Ouellet, C; Piepke, A; Pocar, A; Prescott, C Y; Pushkin, K; Rowson, P C; Russell, J J; Sabourov, A; Sinclair, D; Slutsky, S; Stekhanov, V; Tolba, T; Tosi, D; Twelker, K; Vogel, P; Vuilleumier, J -L; Waite, A; Walton, T; Weber, M; Wichoski, U; Wodin, J; Wright, J D; Yang, L; Yen, Y -R; Zeldovich, O Ya

    2012-01-01

    We report on a search for neutrinoless double-beta decay of $^{136}$Xe with EXO-200. No signal is observed for an exposure of 32.5 kg-yr, with a background of ~1.5 x 10^{-3} /(kg yr keV) in the $\\pm 1\\sigma$ region of interest. This sets a lower limit on the half-life of the neutrinoless double-beta decay $T_{1/2}^{0\

  5. Molecular effects in the neutrino mass determination from beta-decay of the tritium molecule

    International Nuclear Information System (INIS)

    Molecular final state energies and transition probabilities have been computed for beta-decay of the tritium molecule. The results are of sufficient accuracy to make a determination of the electron neutrino rest mass with an error not exceeding a few tenths of an electron volt. Effects of approximate models of tritium beta-decay on the neutrino mass determination are discussed. 14 refs., 3 figs., 1 tab

  6. Light-neutrino masses and hierarchies and the observability of neutrinoless double-beta decay

    CERN Document Server

    Civitarese, O

    2003-01-01

    Results for the neutrino mixing matrix U, obtained from the analysis of SNO, SK and CHOOZ, data, are used to calculate the effective neutrino mass relevant for the neutrinoless double beta decay.The best fit value of U yields an upper limit of 0.03 eV. The observability of the neutrinoless double beta decay is discussed within different neutrino mass hierarchies.

  7. What do we know about neutrinoless double-beta decay nuclear matrix elements?

    CERN Document Server

    Menéndez, J

    2016-01-01

    The detection of neutrinoless double-beta decay will establish the Majorana nature of neutrinos. In addition, if the nuclear matrix elements of this process are reliably known, the experimental lifetime will provide precious information about the absolute neutrino masses and hierarchy. I review the status of nuclear structure calculations for neutrinoless double-beta decay matrix elements, and discuss some key issues to be addressed in order to meet the demand for accurate nuclear matrix elements.

  8. Neutrinoless double beta decay potential in a large mixing angle world

    CERN Document Server

    Klapdor-Kleingrothaus, Hans Volker; Smirnov, Yu A

    2001-01-01

    We discuss the possibility of reconstructing the neutrino mass spectrum from the complementary processes of neutrino oscillations and double beta decay in view of the new data of Super-Kamiokande presented at the Neutrino2000 conference. Since the large mixing angle solution is favored, now, the prospects to observe double beta decay and provide informations on the absolute mass scale in the neutrino sector have been improved.

  9. Light neutrino contribution: is it all there is to neutrinoless double beta decay?

    CERN Document Server

    Mahajan, Namit

    2015-01-01

    We consider perturbative one loop QCD corrections to the light neutrino contribution to neutrinoless double beta decay and find large enhancement to the rate. QCD corrections also generate structures which mimic new physics contributions usually considered. Within some approximations, the net effect seem to almost saturate the experimental limits, and therefore seems to implt that this is all there is to neutrinoless double beta decay.

  10. Consensus Report of a Workshop on "Matrix elements for Neutrinoless Double Beta Decay"

    OpenAIRE

    Zuber, K.

    2005-01-01

    This is the consensus of a Workshop on "Matrix elements for Neutrinoless Double Beta Decay" held at the IPPP Durham (UK). The aim of this workshop has been to define a well planned, coherent strategy to reduce the errors on nuclear matrix element calculations for double beta decay to a level of 30% by performing the necessary measurements with currently existing and planned facilities. These measurements should provide reliable input for the theoretical calculations. The outcome of the worksh...

  11. Double beta decays of 100Mo by ELEGANT V at Oto Cosmo Observatory

    International Nuclear Information System (INIS)

    Exclusive measurements of neutrino-less double beta decays(0νββ) of 100Mo were made by means of ELEGANT V. The present status of the double beta decay experiment with ELEGANT V is presented. The data at Oto lab., being combined with the data at Kamioka, gives stringent limits on half-lives for 0νββ and < 1.7 eV

  12. Measurement of the beta beta Decay Half-Life of Te-130 with the NEMO-3 Detector

    OpenAIRE

    Arnold, R.; Augier, C.; Baker, J.; Barabash, A. S.; Basharina-Freshville, A.; Blondel, S.; Bongrand, M.; Broudin-Bay, G.; Brudanin, V.(Joint Institute for Nuclear Research, Dubna, Russia); Caffrey, A. J.; Chapon, A.; Chauveau, E.; Durand, D.; Egorov, V.; Flack, R.

    2011-01-01

    We report results from the NEMO-3 experiment based on an exposure of 1275 days with 661 g of Te-130 in the form of enriched and natural tellurium foils. The beta beta decay rate of Te-130 is found to be greater than zero with a significance of 7.7 standard deviations and the half-life is measured to be T-1/2(2v)=[7.0 +/- 0.9(stat) +/- 1: 1(syst)] x 10(20) yr. This represents the most precise measurement of this half- life yet published and the first real-time observation of this decay.

  13. Gross theory of beta-decay and half-lives of short-lived nuclei

    International Nuclear Information System (INIS)

    The gross theory of beta-decay has been developed, and this theory offers the means of calculating directly the function of beta-decay intensity, then half-lives, complex beta spectra and so on are estimated from it. This paper presents the more refined theory by introducing the shell effect. The shell effect is considered in the intensity function. The half-lives in the electron decay of In with spin of 9/2+, the positron decay of Bi, Po, At and Rn, and the decay of odd-odd nuclei were estimated. The introduction of the shell effect shows better agreement between the theory and the experimental data. The inequality relations of intensity functions and half-lives of two adjacent nuclei were obtained. When the spins and parities of two nuclei are same, the inequality relations hold especially good. (Kato, T.)

  14. Measurements of the branching fractions of $B^{+} \\to p \\bar{p} K^{+}$ decays

    CERN Document Server

    Aaij, R; Adametz, A; Adeva, B; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves Jr, A A; Amato, S; Amhis, Y; Anderlini, L; Anderson, J; Andreassen, R; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Bachmann, S; Back, J J; Baesso, C; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bauer, Th; Bay, A; Beddow, J; Bediaga, I; Belogurov, S; Belous, K; Belyaev, I; Ben-Haim, E; Benayoun, M; Bencivenni, G; Benson, S; Benton, J; Berezhnoy, A; Bernet, R; Bettler, M -O; van Beuzekom, M; Bien, A; Bifani, S; Bird, T; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blanks, C; Blouw, J; Blusk, S; Bobrov, A; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Bowcock, T J V; Bowen, E; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Britsch, M; Britton, T; Brook, N H; Brown, H; Burducea, I; Bursche, A; Buytaert, J; Cadeddu, S; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carranza-Mejia, H; Carson, L; Carvalho Akiba, K; Casse, G; Cattaneo, M; Cauet, Ch; Charles, M; Charpentier, Ph; Chen, P; Chiapolini, N; Chrzaszcz, M; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coca, C; Coco, V; Cogan, J; Cogneras, E; Collins, P; Comerma-Montells, A; Contu, A; Cook, A; Coombes, M; Coquereau, S; Corti, G; Couturier, B; Cowan, G A; Craik, D; Cunliffe, S; Currie, R; D'Ambrosio, C; David, P; David, P N Y; De Bonis, I; De Bruyn, K; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Silva, W; De Simone, P; Decamp, D; Deckenhoff, M; Degaudenzi, H; Del Buono, L; Deplano, C; Derkach, D; Deschamps, O; Dettori, F; Di Canto, A; Dickens, J; Dijkstra, H; Dogaru, M; Domingo Bonal, F; Donleavy, S; Dordei, F; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Dzhelyadin, R; Dziurda, A; Dzyuba, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisenhardt, S; Eitschberger, U; Ekelhof, R; Eklund, L; El Rifai, I; Elsasser, Ch; Elsby, D; Falabella, A; Färber, C; Fardell, G; Farinelli, C; Farry, S; Fave, V; Ferguson, D; Fernandez Albor, V; Ferreira Rodrigues, F; Ferro-Luzzi, M; Filippov, S; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Francisco, O; Frank, M; Frei, C; Frosini, M; Furcas, S; Furfaro, E; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garofoli, J; Garosi, P; Garra Tico, J; Garrido, L; Gaspar, C; Gauld, R; Gersabeck, E; Gersabeck, M; Gershon, T; Ghez, Ph; Gibson, V; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Grünberg, O; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hall, S; Hampson, T; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; Harrison, P F; Hartmann, T; He, J; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Hicks, E; Hill, D; Hoballah, M; Hombach, C; Hopchev, P; Hulsbergen, W; Hunt, P; Huse, T; Hussain, N; Hutchcroft, D; Hynds, D; Iakovenko, V; Ilten, P; Jacobsson, R; Jaeger, A; Jans, E; Jansen, F; Jaton, P; Jing, F; John, M; Johnson, D; Jones, C R; Jost, B; Kaballo, M; Kandybei, S; Karacson, M; Karbach, T M; Kenyon, I R; Kerzel, U; Ketel, T; Keune, A; Khanji, B; Kochebina, O; Komarov, I; Koopman, R F; Koppenburg, P; Korolev, M; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kucharczyk, M; Kudryavtsev, V; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Latham, T; Lazzeroni, C; Le Gac, R; van Leerdam, J; Lees, J -P; Lefèvre, R; Leflat, A; Lefrançois, J; Leroy, O; Li, Y; Li Gioi, L; Liles, M; Lindner, R; Linn, C; Liu, B; Liu, G; von Loeben, J; Lopes, J H; Lopez Asamar, E; Lopez-March, N; Lu, H; Luisier, J; Luo, H; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Malde, S; Manca, G; Mancinelli, G; Mangiafave, N; Marconi, U; Märki, R; Marks, J; Martellotti, G; Martens, A; Martin, L; Martín Sánchez, A; Martinelli, M; Martinez Santos, D; Martins Tostes, D; Massafferri, A; Matev, R; Mathe, Z; Matteuzzi, C; Matveev, M; Maurice, E; Mazurov, A; McCarthy, J; McNulty, R; Meadows, B; Meier, F; Meissner, M; Merk, M; Milanes, D A; Minard, M -N; Molina Rodriguez, J; Monteil, S; Moran, D; Morawski, P; Mountain, R; Mous, I; Muheim, F; Müller, K; Muresan, R; Muryn, B; Muster, B; Naik, P; Nakada, T; Nandakumar, R; Nasteva, I; Needham, M; Neufeld, N; Nguyen, A D; Nguyen, T D; Nguyen-Mau, C; Nicol, M; Niess, V; Niet, R; Nikitin, N; Nikodem, T; Nisar, S; Nomerotski, A; Novoselov, A; Oblakowska-Mucha, A; Obraztsov, V; Oggero, S; Ogilvy, S; Okhrimenko, O; Oldeman, R; Orlandea, M; Otalora Goicochea, J M; Owen, P; Pal, B K; Palano, A; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Parkes, C; Parkinson, C J; Passaleva, G; Patel, G D; Patel, M; Patrick, G N; Patrignani, C; Pavel-Nicorescu, C; Pazos Alvarez, A; Pellegrino, A; Penso, G; Pepe Altarelli, M; Perazzini, S; Perego, D L; Perez Trigo, E; Pérez-Calero Yzquierdo, A; Perret, P; Perrin-Terrin, M; Pessina, G; Petridis, K; Petrolini, A; Phan, A; Picatoste Olloqui, E; Pietrzyk, B; Pilař, T; Pinci, D; Playfer, S; Plo Casasus, M; Polci, F; Polok, G; Poluektov, A; Polycarpo, E; Popov, D; Popovici, B; Potterat, C; Powell, A; Prisciandaro, J; Pugatch, V; Puig Navarro, A; Qian, W; Rademacker, J H; Rakotomiaramanana, B; Rangel, M S; Raniuk, I; Rauschmayr, N; Raven, G; Redford, S; Reid, M M; dos Reis, A C; Ricciardi, S; Richards, A; Rinnert, K; Rives Molina, V; Roa Romero, D A; Robbe, P; Rodrigues, E; Rodriguez Perez, P; Rogers, G J; Roiser, S; Romanovsky, V; Romero Vidal, A; Rouvinet, J; Ruf, T; Ruiz, H; Sabatino, G; Saborido Silva, J J; Sagidova, N; Sail, P; Saitta, B; Salzmann, C; Sanmartin Sedes, B; Sannino, M; Santacesaria, R; Santamarina Rios, C; Santovetti, E; Sapunov, M; Sarti, A; Satriano, C; Satta, A; Savrie, M; Savrina, D; Schaack, P; Schiller, M; Schindler, H; Schleich, S; Schlupp, M; Schmelling, M; Schmidt, B; Schneider, O; Schopper, A; Schune, M -H; Schwemmer, R; Sciascia, B; Sciubba, A; Seco, M; Semennikov, A; Senderowska, K; Sepp, I; Serra, N; Serrano, J; Seyfert, P; Shapkin, M; Shapoval, I; Shatalov, P; Shcheglov, Y; Shears, T; Shekhtman, L; Shevchenko, O; Shevchenko, V; Shires, A; Silva Coutinho, R; Skwarnicki, T; Smith, N A; Smith, E; Smith, M; Sobczak, K; Sokoloff, M D; Soler, F J P; Soomro, F; Souza, D; Souza De Paula, B; Spaan, B; Sparkes, A; Spradlin, P; Stagni, F; Stahl, S; Steinkamp, O; Stoica, S; Stone, S; Storaci, B; Straticiuc, M; Straumann, U; Subbiah, V K; Swientek, S; Syropoulos, V; Szczekowski, M; Szczypka, P; Szumlak, T; T'Jampens, S; Teklishyn, M; Teodorescu, E; Teubert, F; Thomas, C; Thomas, E; van Tilburg, J; Tisserand, V; Tobin, M; Tolk, S; Tonelli, D; Topp-Joergensen, S; Torr, N; Tournefier, E; Tourneur, S; Tran, M T; Tresch, M; Tsaregorodtsev, A; Tsopelas, P; Tuning, N; Ubeda Garcia, M; Ukleja, A; Urner, D; Uwer, U; Vagnoni, V; Valenti, G; Vazquez Gomez, R; Vazquez Regueiro, P; Vecchi, S; Velthuis, J J; Veltri, M; Veneziano, G; Vesterinen, M; Viaud, B; Vieira, D; Vilasis-Cardona, X; Vollhardt, A; Volyanskyy, D; Voong, D; Vorobyev, A; Vorobyev, V; Voß, C; Voss, H; Waldi, R; Wallace, R; Wandernoth, S; Wang, J; Ward, D R; Watson, N K; Webber, A D; Websdale, D; Whitehead, M; Wicht, J; Wiechczynski, J; Wiedner, D; Wiggers, L; Wilkinson, G; Williams, M P; Williams, M; Wilson, F F; Wishahi, J; Witek, M; Wotton, S A; Wright, S; Wu, S; Wyllie, K; Xie, Y; Xing, F; Xing, Z; Yang, Z; Young, R; Yuan, X; Yushchenko, O; Zangoli, M; Zavertyaev, M; Zhang, F; Zhang, L; Zhang, W C; Zhang, Y; Zhelezov, A; Zhong, L; Zvyagin, A

    2013-01-01

    The branching fractions of the decay $B^{+} \\to p \\bar p K^{+}$ for different intermediate states are measured using data, corresponding to an integrated luminosity of 1.0 fb$^{-1}$, collected by the LHCb experiment. The total branching fraction, its charmless component $(M_{p\\bar p} <2.85 $ $ GeV/c^{2})$ and the branching fractions via the resonant $c\\bar c$ states $\\eta_{c}(1S)$ and $\\psi(2S)$ relative to the decay via a $J/\\psi$ intermediate state are \\begin{align*} \\frac{{\\mathcal B}(B^{+} \\to p \\bar p K^{+})_{total}}{{\\mathcal B}(B^{+} \\to J/\\psi K^{+} \\to p \\bar p K^{+})}=& \\, 4.91 \\pm 0.19 \\, {(\\rm stat)} \\pm 0.14 \\, {(\\rm syst)},\\\\ \\frac{{\\mathcal B}(B^{+} \\to p \\bar p K^{+})_{M_{p\\bar p} <2.85 {GeV/}c^{2}}}{{\\mathcal B}(B^{+} \\to J/\\psi K^{+} \\to p \\bar p K^{+})}=& \\, 2.02 \\pm 0.10 \\, {(\\rm stat)}\\pm 0.08 \\, {(\\rm syst)},\\\\ \\frac{{\\mathcal B} (B^{+} \\to \\eta_{c}(1S) K^{+} \\to p \\bar p K^{+})}{{\\mathcal B}(B^{+} \\to J/\\psi K^{+} \\to p \\bar p K^{+})} = & \\, 0.578 \\pm 0.03...

  15. Influence of pairing in double beta decay of48Ca

    Indian Academy of Sciences (India)

    Prianka Roy; Shashi K Dhiman

    2010-03-01

    Two-neutrino decay matrix elements and half-life of 48Ca are calculated after including neutron–proton pairing correlations in projected Hartree–Fock–Bogoliubov (PHFB) formalism. The GT matrix elements in 2 decay are reduced due to broader smearing of Fermi surfaces. Half-life results for 2 decay of 48Ca with np pairing are better than without pairing.

  16. Failure of the gross theory of beta decay in neutron deficient nuclei

    International Nuclear Information System (INIS)

    The neutron deficient isotopes 117-121Xe, 117-124Cs, and 122-124Ba were produced by a beam of 28Si from the LBNL SuperHILAC on a target of natMo. The isotopes were mass separated and their beta decay schemes were measured with a Total Absorption Spectrometer (TAS). The beta strengths derived from these data decreased dramatically to levels above ≈1 MeV for the even-even decays; 3–4 MeV for even-Z, odd-N decays; 4–5 MeV for the odd-Z, even-N decays; and 7–8 MeV for the odd-Z, odd-N decays. The decreasing strength to higher excitation energies in the daughters contradicts the predictions of the Gross Theory of Beta Decay. The integrated beta strengths are instead found to be consistent with shell model predictions where the single-particle beta strengths are divided amoung many low-lying levels. The experimental beta strengths determined here have been used calculate the half-lives of 143 neutron deficient nuclei with Z=51–64 to a precision of 20% with respect to the measured values

  17. Measurement of the branching fraction and $CP$ asymmetry in radiative $D^0 \\to V \\gamma$ decays

    CERN Document Server

    Abdesselam, A; Adamczyk, K; Aihara, H; Said, S Al; Arinstein, K; Arita, Y; Asner, D M; Aso, T; Atmacan, H; Aulchenko, V; Aushev, T; Ayad, R; Aziz, T; Babu, V; Badhrees, I; Bahinipati, S; Bakich, A M; Bala, A; Ban, Y; Bansal, V; Barberio, E; Barrett, M; Bartel, W; Bay, A; Bedny, I; Behera, P; Belhorn, M; Belous, K; Besson, D; Bhardwaj, V; Bhuyan, B; Bischofberger, M; Biswal, J; Bloomfield, T; Blyth, S; Bobrov, A; Bondar, A; Bonvicini, G; Bookwalter, C; Boulahouache, C; Bozek, A; Bračko, M; Breibeck, F; Brodzicka, J; Browder, T E; Červenkov, D; Chang, M -C; Chang, P; Chao, Y; Chekelian, V; Chen, A; Chen, K -F; Chen, P; Cheon, B G; Chilikin, K; Chistov, R; Cho, K; Chobanova, V; Choi, S -K; Choi, Y; Cinabro, D; Crnkovic, J; Dalseno, J; Danilov, M; Dash, N; Di Carlo, S; Dingfelder, J; Doležal, Z; Drásal, Z; Drutskoy, A; Dubey, S; Dutta, D; Dutta, K; Eidelman, S; Epifanov, D; Esen, S; Farhat, H; Fast, J E; Feindt, M; Ferber, T; Frey, A; Frost, O; Fujikawa, M; Fulsom, B G; Gaur, V; Gabyshev, N; Ganguly, S; Garmash, A; Getzkow, D; Gillard, R; Giordano, F; Glattauer, R; Goh, Y M; Goldenzweig, P; Golob, B; Greenwald, D; Perdekamp, M Grosse; Grygier, J; Grzymkowska, O; Guo, H; Haba, J; Hamer, P; Han, Y L; Hara, K; Hara, T; Hasegawa, Y; Hasenbusch, J; Hayasaka, K; Hayashii, H; He, X H; Heck, M; Hedges, M T; Heffernan, D; Heider, M; Heller, A; Higuchi, T; Himori, S; Hirose, S; Horiguchi, T; Hoshi, Y; Hoshina, K; Hou, W -S; Hsiung, Y B; Hsu, C -L; Huschle, M; Hyun, H J; Igarashi, Y; Iijima, T; Imamura, M; Inami, K; Inguglia, G; Ishikawa, A; Itagaki, K; Itoh, R; Iwabuchi, M; Iwasaki, M; Iwasaki, Y; Iwata, S; Jacobs, W W; Jaegle, I; Jeon, H B; Joffe, D; Jones, M; Joo, K K; Julius, T; Kakuno, H; Kang, J H; Kang, K H; Kapusta, P; Kataoka, S U; Kato, E; Kato, Y; Katrenko, P; Kawai, H; Kawasaki, T; Keck, T; Kichimi, H; Kiesling, C; Kim, B H; Kim, D Y; Kim, H J; Kim, H -J; Kim, J B; Kim, J H; Kim, K T; Kim, M J; Kim, S H; Kim, S K; Kim, Y J; Kinoshita, K; Kleinwort, C; Klucar, J; Ko, B R; Kobayashi, N; Koblitz, S; Kodyš, P; Koga, Y; Korpar, S; Kotchetkov, D; Kouzes, R T; Križan, P; Krokovny, P; Kronenbitter, B; Kuhr, T; Kumar, R; Kumita, T; Kurihara, E; Kuroki, Y; Kuzmin, A; Kvasnička, P; Kwon, Y -J; Lai, Y -T; Lange, J S; Lee, D H; Lee, I S; Lee, S -H; Leitgab, M; Leitner, R; Levit, D; Lewis, P; Li, C H; Li, H; Li, J; Li, L; Li, X; Li, Y; Gioi, L Li; Libby, J; Limosani, A; Liu, C; Liu, Y; Liu, Z Q; Liventsev, D; Loos, A; Louvot, R; Lubej, M; Lukin, P; Luo, T; MacNaughton, J; Masuda, M; Matsuda, T; Matvienko, D; Matyja, A; McOnie, S; Mikami, Y; Miyabayashi, K; Miyachi, Y; Miyake, H; Miyata, H; Miyazaki, Y; Mizuk, R; Mohanty, G B; Mohanty, S; Mohapatra, D; Moll, A; Moon, H K; Mori, T; Morii, T; Moser, H -G; Müller, T; Muramatsu, N; Mussa, R; Nagamine, T; Nagasaka, Y; Nakahama, Y; Nakamura, I; Nakamura, K R; Nakano, E; Nakano, H; Nakano, T; Nakao, M; Nakayama, H; Nakazawa, H; Nanut, T; Nath, K J; Natkaniec, Z; Nayak, M; Nedelkovska, E; Negishi, K; Neichi, K; Ng, C; Niebuhr, C; Niiyama, M; Nisar, N K; Nishida, S; Nishimura, K; Nitoh, O; Nozaki, T; Ogawa, A; Ogawa, S; Ohshima, T; Okuno, S; Olsen, S L; Ono, Y; Onuki, Y; Ostrowicz, W; Oswald, C; Ozaki, H; Pakhlov, P; Pakhlova, G; Pal, B; Palka, H; Panzenböck, E; Park, C -S; Park, C W; Park, H; Park, K S; Paul, S; Peak, L S; Pedlar, T K; Peng, T; Pesántez, L; Pestotnik, R; Peters, M; Petrič, M; Piilonen, L E; Poluektov, A; Prasanth, K; Prim, M; Prothmann, K; Pulvermacher, C; Purohit, M V; Rauch, J; Reisert, B; Ribežl, E; Ritter, M; Röhrken, M; Rorie, J; Rostomyan, A; Rozanska, M; Rummel, S; Ryu, S; Sahoo, H; Saito, T; Sakai, K; Sakai, Y; Sandilya, S; Santel, D; Santelj, L; Sanuki, T; Sasao, N; Sato, Y; Savinov, V; Schlüter, T; Schneider, O; Schnell, G; Schönmeier, P; Schram, M; Schwanda, C; Schwartz, A J; Schwenker, B; Seidl, R; Seino, Y; Sekiya, A; Semmler, D; Senyo, K; Seon, O; Seong, I S; Sevior, M E; Shang, L; Shapkin, M; Shebalin, V; Shen, C P; Shibata, T -A; Shibuya, H; Shinomiya, S; Shiu, J -G; Shwartz, B; Sibidanov, A; Simon, F; Singh, J B; Sinha, R; Smerkol, P; Sohn, Y -S; Sokolov, A; Soloviev, Y; Solovieva, E; Stanič, S; Starič, M; Steder, M; Strube, J F; Stypula, J; Sugihara, S; Sugiyama, A; Sumihama, M; Sumisawa, K; Sumiyoshi, T; Suzuki, K; Suzuki, S; Suzuki, S Y; Suzuki, Z; Takeichi, H; Takizawa, M; Tamponi, U; Tanaka, M; Tanaka, S; Tanida, K; Taniguchi, N; Taylor, G N; Teramoto, Y; Tikhomirov, I; Trabelsi, K; Trusov, V; Tse, Y F; Tsuboyama, T; Uchida, M; Uchida, T; Uehara, S; Ueno, K; Uglov, T; Unno, Y; Uno, S; Uozumi, S; Urquijo, P; Ushiroda, Y; Usov, Y; Vahsen, S E; Van Hulse, C; Vanhoefer, P; Varner, G; Varvell, K E; Vervink, K; Vinokurova, A; Vorobyev, V; Vossen, A; Wagner, M N; Wang, C H; Wang, J; Wang, M -Z; Wang, P; Wang, X L; Watanabe, M; Watanabe, Y; Wedd, R; Wehle, S; White, E; Wiechczynski, J; Williams, K M; Won, E; Yabsley, B D; Yamada, S; Yamamoto, H; Yamaoka, J; Yamashita, Y; Yamauchi, M; Yashchenko, S; Ye, H; Yelton, J; Yook, Y; Yuan, C Z; Yusa, Y; Zhang, C C; Zhang, L M; Zhang, Z P; Zhao, L; Zhilich, V; Zhukova, V; Zhulanov, V; Ziegler, M; Zivko, T; Zupanc, A; Zwahlen, N; Zyukova, O

    2016-01-01

    We report a measurement of the branching fractions of the radiative decays $D^0 \\to V \\gamma$, where $V=\\phi,~\\overline{K}{}^{*0}$ or $\\rho^0$. This is the first observation of the decay $D^0 \\to \\rho^0 \\gamma$. We measure preliminary branching fractions $\\mathcal{B}(D^0 \\to \\phi \\gamma)=(2.76 \\pm 0.20 \\pm 0.08) \\times 10^{-5}$, $\\mathcal{B}(D^0 \\to \\overline{K}{}^{*0} \\gamma)=(4.66 \\pm 0.21 \\pm 0.18) \\times 10^{-4} $ and $\\mathcal{B}(D^0 \\to \\rho^0 \\gamma)=(1.77 \\pm 0.30 \\pm 0.08) \\times 10^{-5}$, where the first uncertainty is statistical and the second systematic. We also present the first measurement of $CP$ asymmetry in these decays. The preliminary values are $\\mathcal{A}_{CP}(D^0 \\to \\phi \\gamma)=-(0.094 \\pm 0.066 \\pm 0.001)$, $\\mathcal{A}_{CP}(D^0 \\to \\overline{K}{}^{*0} \\gamma)=-(0.003 \\pm 0.020 \\pm 0.000)$ and $\\mathcal{A}_{CP}(D^0 \\to \\rho^0 \\gamma)=0.056 \\pm 0.151 \\pm 0.006$. The analysis was conducted using 943 fb$^{-1}$ of data collected by the Belle detector at the KEKB $e^+e^-$ collider.

  18. Improved Measurements of Neutral B Decay Branching Fractions to K0s pi+ pi- and the Charge Asymmetry of B0 -> K*+ pi-

    Energy Technology Data Exchange (ETDEWEB)

    Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; /Annecy, LAPP; Grauges, E.; /Barcelona, IFAE; Palano, A.; Pappagallo, M.; Pompili, A.; /Bari U. /INFN, Bari; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; /Beijing, Inst. High Energy Phys.; Eigen, G.; Ofte, I.; Stugu, B.

    2005-08-26

    The authors analyze the decay B{sup 0} {yields} K{sub S}{sup 0}{pi}{sup +}{pi}{sup -} using a sample of 232 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the SLAC PEP-II asymmetric-energy B factory. A maximum likelihood fit finds the following branching fractions: {Beta}(B{sup 0} {yields} K{sup 0}{pi}{sup +}{pi}{sup -}) = (43.0 {+-} 2.3 {+-} 2.3) x 10{sup -6}, {Beta}(B{sup 0} {yields} f{sub 0}({yields} {pi}{sup +}{pi}{sup -})K{sup 0}) = (5.5 {+-} 0.7 {+-} 0.5 {+-} 0.3) x 10{sup -6} and {Beta}(B{sup 0} {yields} K*{sup +}{pi}{sup -}) = (11.0 {+-} 1.5 {+-} 0.5 {+-} 0.5) x 10{sup -6}. For these results, the first uncertainty is statistical, the second is systematic, and the third (if present) is due to the effect of interference from other resonances. They also measure the CP-violating charge asymmetry in the decay B{sup 0} {yields} K*{sup +}{pi}{sup -}, {Alpha}{sub K*{pi}} = -0.11 {+-} 0.14 {+-} 0.05.

  19. Gamow-Teller strength distributions for double-beta-decaying nuclei within continuum-QRPA

    OpenAIRE

    Igashov, S. Yu.; Rodin, V. A.; Urin, M.H.; Faessler, A.

    2007-01-01

    A version of the pn-continuum-QRPA is outlined and applied to describe the Gamow-Teller strength distributions for $\\beta\\beta$-decaying open-shell nuclei. The calculation results obtained for the pairs of nuclei $^{116}$Cd-Sn and $^{130}$Te-Xe are compared with available experimental data.

  20. Measurement of Branching Fractions and Rate Asymmetries in the Rare Decays B -> K(*) l+ l-

    CERN Document Server

    ,

    2012-01-01

    In a sample of 471 million BB events collected with the BABAR detector at the PEP-II e+e- collider we study the rare decays B -> K(*) l+ l-, where l+ l- is either e+e- or mu+mu-. We report results on partial branching fractions and isospin asymmetries in seven bins of di-lepton mass-squared. We further present CP and lepton-flavor asymmetries for di-lepton masses below and above the J/psi resonance. We find no evidence for CP or lepton-flavor violation. The partial branching fractions and isospin asymmetries are consistent with the Standard Model predictions and with results from other experiments.

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

    CERN Document Server

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

    2002-01-01

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

  2. Measurement of the Branching Fraction of B0 Meson Decay to a_1^+(1260) pi-

    Energy Technology Data Exchange (ETDEWEB)

    Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; /Annecy, LAPP; Grauges, E.; /Barcelona, IFAE; Palano, A.; Pappagallo, M.; Pompili, A.; /Bari U. /INFN, Bari; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; /Beijing, Inst. High Energy Phys.; Eigen, G.; Ofte, I.; Stugu, B.

    2005-07-12

    We present a preliminary measurement of the branching fraction of the B meson decay B{sup 0} {yields} a{sub 1}{sup +}(1260){pi}{sup -}with a{sub 1}{sup +}(1260) {yields} {pi}{sup +}{pi}{sup +}{pi}{sup -}. The data sample corresponds to 218 x 10{sup 6} B{bar B} pairs produced in e{sup +}e{sup -} annihilation through the {Upsilon}(4S) resonance. We find the branching fraction (40.2 {+-} 3.9 {+-} 3.9) x 10{sup -6}, where the first error quoted is statistical and the second is systematic. The fitted values of the a{sub 1}(1260) parameters are m{sub a{sub 1}} = 1.22 {+-} 0.02 GeV/c{sup 2} and {Lambda}{sub a{sub 1}} = 0.423 {+-} 0.050 GeV/c{sup 2}.

  3. Generalized solutions of the Dirac equation, W bosons, and beta decay

    CERN Document Server

    Okninski, Andrzej

    2016-01-01

    We study the 7x7 Hagen-Hurley equations describing spin 1 particles. We split these equations, in the interacting case, into two Dirac equations with non-standard solutions. It is argued that these solutions describe decay of a virtual W boson in beta decay.

  4. Spectrum of secondary electrons emitted during the nuclear $\\beta^{-}$-decay of the tritium atom

    CERN Document Server

    Frolov, Alexei M

    2015-01-01

    We discuss ionization of the final ${}^{3}$He$^{+}$ ion during the nuclear $\\beta^{-}$-decay of the tritium atom. The velocity spectrum of secondary electrons emitted during such a decay is derived in the explicit form. Our method allows one to determine both the relative and absolute probabilities of formation of the final states with certain velocities of secondary electrons.

  5. CP-Violation in Neutrino Oscillations from EC/{beta}{sup +} decaying ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Espinoza, Catalina [Centre for Theoretical Particle Physics, IST, Technical University of Lisbon, Av. Rovisco Pais 1, 1049-001 Lisboa (Portugal)

    2012-08-15

    We discuss the separation of unknown neutrino properties by means of the energy dependence of the oscillation probability and we consider an hybrid setup which combines the electron capture and the {beta}{sup +} decay from the same radioactive proton-rich ion with the same boost. We conclude that the combination of the two decay channels, with different neutrino energies, achieves remarkable results.

  6. Investigation of the Majoron-accompanied double-beta decay mode of [sup 76]Ge

    Energy Technology Data Exchange (ETDEWEB)

    Beck, M.; Bensch, F.; Bockholt, J.; Heusser, G.; Hirsch, M.; Klapdor-Kleingrothaus, H.V.; Maier, B.; Petry, F.; Piepke, A.; Strecker, H.; Voellinger, M.; Zuber, K.; Balysh, A.; Belyaev, S.T.; Demehin, A.; Gurov, A.; Kondratenko, I.; Lebedev, V.I.; Mueller, A. (Max-Planck-Institut fuer Kernphysik, P.O. Box 103980, 6900 Heidelberg (Germany) Kurchatov Institute, Moscow (Russian Federation) LNGS, Istituto Nazionale di Fisica Nucleare, Gran Sasso, Assergi (Italy))

    1993-05-10

    We have examined the double-beta decay mode accompanied by Majoron emission. After 223 days of measurement corresponding to about 615 kg d or 19.3 mol yr of exposure we find a lower half-life limit for this decay channel of [ital T][sub 1/2][sup 0[nu][chi

  7. Properties of low-lying intruder states in $^{34}$Al and $^{34}$Si sequentially populated in $\\beta$-decay of $^{34}$Mg

    CERN Multimedia

    A low-lying long-lived (26±1 ms) isomer in $^{34}$Al has been observed recently and assigned as 1$^{+}$ state of intruder character. It was populated in $^{36}$S fragmentation and feeds, in $\\beta$-decay, the 0$_{2}^{+}$ state in $^{34}$Si whose excitation energy and lifetime were determined in an electron-positron pairs spectroscopy experiment. In the present experiment we intend to measure for the first time the $\\gamma$-rays following the $\\beta$-decay of $^{34}$Mg. Despite the interest for $^{34}$Mg, the up-right corner of the “N$\\thicksim$20 island of inversion”, the only information on its $\\beta$-decay is the lifetime of 20±10 ms, determined from $\\beta$-neutron coincidences. As a result of the proposed experiment, we expect to place the first transitions in the level scheme of $^{34}$Al and to strongly populate the newly observed isomer, measuring its excitation energy, if the branching ratio to 4$^{−}$ ground state is significant. Theoretical estimations for the $\\beta$-decay of the new isome...

  8. Observation of the Decay B0 => rho+ rho- and Measurement of the Branching Fraction and Polarization

    CERN Document Server

    Aubert, Bernard; Boutigny, D; Couderc, F; Gaillard, J M; Hicheur, A; Karyotakis, Yu; Lees, J P; Tisserand, V; Zghiche, A; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Le Clerc, C; Levi, M E; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, Michael T; Shelkov, V G; Telnov, A V; Wenzel, W A; Ford, K; Harrison, T J; Hawkes, C M; Morgan, S E; Watson, A T; Watson, N K; Fritsch, M; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schmücker, H; Steinke, M; Boyd, J T; Chevalier, N; Cottingham, W N; Kelly, M P; Latham, T E; MacKay, C; Wilson, F F; Abe, K; Çuhadar-Dönszelmann, T; Hearty, C; Mattison, T S; McKenna, J A; Thiessen, D; Kyberd, P; McKemey, A K; Teodorescu, L; Blinov, V E; Bukin, A D; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bruinsma, M; Chao, M; Eschrich, I; Kirkby, D; Lankford, A J; Mandelkern, M A; Mommsen, R K; Röthel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Gary, J W; Layter, J; Shen, B C; Wang, K; Del Re, D; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Dahmes, B; Levy, S L; Long, O; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Beringer, J; Eisner, A M; Heusch, C A; Lockman, W S; Schalk, T; Schmitz, R E; Schumm, B A; Seiden, A; Spradlin, P; Walkowiak, W; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Erwin, R J; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S M; Mancinelli, G; Meadows, B T; Sokoloff, M D; Abe, T; Blanc, F; Bloom, P; Chen, S; Clark, P J; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Roy, J; Smith, J G; Van Hoek, W C; Zhang, L; Harton, J L; Hu, T; Soffer, A; Toki, W H; Wilson, R J; Zhang, J; Altenburg, D; Brandt, T; Brose, J; Colberg, T; Dickopp, M; Feltresi, E; Hauke, A; Lacker, H M; Maly, E; Müller-Pfefferkorn, R; Nogowski, R; Otto, S; Schubert, J; Schubert, Klaus R; Schwierz, R; Spaan, B; Bernard, D; Bonneaud, G R; Brochard, F; Grenier, P; Thiebaux, C; Vasileiadis, G; Verderi, M; Bard, D J; Khan, A; Lavin, D; Muheim, F; Playfer, S; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Sarti, A; Treadwell, E; Baldini-Ferroli, R; Calcaterra, A; De Sangro, R; Finocchiaro, G; Patteri, P; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Morii, M; Won, E; Dubitzky, R S; Langenegger, U; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Gaillard, J R; Morton, G W; Nash, J A; Taylor, G P; Grenier, G J; Lee, S J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Prell, S; Rosenberg, E I; Yi, J; Davier, M; Grosdidier, G; Höcker, A; Laplace, S; Le Diberder, F R; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Tantot, L; Wormser, G; Brigljevic, V; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Coleman, J P; Fry, J R; Gabathuler, Erwin; Gamet, R; Kay, M; Parry, R J; Payne, D J; Sloane, R J; Touramanis, C; Back, J J; Harrison, P F; Mohanty, G B; Brown, C L; Cowan, G; Flack, R L; Flächer, H U; George, S; Green, M G; Kurup, A; Marker, C E; McMahon, T R; Ricciardi, S; Salvatore, F; Vaitsas, G; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Hart, P A; Hodgkinson, M C; Lafferty, G D; Lyon, A J; Williams, J C; Farbin, A; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Saremi, S; Stängle, H; Willocq, S; Cowan, R; Sciolla, G; Taylor, F; Yamamoto, R K; Mangeol, D J J; Patel, P M; Robertson, S H; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L M; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Cote-Ahern, D; Taras, P; Nicholson, H; Cartaro, C; Cavallo, N; De Nardo, Gallieno; Fabozzi, F; Gatto, C; Lista, L; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M A; Raven, G; Wilden, L; Jessop, C P; LoSecco, J M; Gabriel, T A; Allmendinger, T; Brau, B; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pulliam, T; Ter-Antonian, R; Wong, Q K; Brau, J E; Frey, R; Igonkina, O; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Tiozzo, G; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; La Vaissière, C de; Del Buono, L; Hamon, O; John, M J J; Leruste, P; Ocariz, J; Pivk, M; Roos, L; T'Jampens, S; Therin, G; Manfredi, P F; Re, V; Behera, P K; Gladney, L; Guo, Q H; Panetta, J; Anulli, F; Biasini, M; Peruzzi, I M; Pioppi, M; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Bucci, F; Calderini, G; Carpinelli, M; Del Gamba, V; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Martínez-Vidal, F; Morganti, M; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Sandrelli, F; Walsh, J; Haire, M; Judd, D; Paick, K; Wagoner, D E; Danielson, N; Elmer, P; Lü, C; Miftakov, V; Olsen, J; Smith, A J S; Varnes, E W; Bellini, F; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Mazzoni, M A; Morganti, S; Pierini, M; Piredda, G; Safai-Tehrani, F; Voena, C; Christ, S; Wagner, G; Waldi, R; Adye, T; De, N; De Groot, J G H; Franek, B J; Geddes, N I; Gopal, G P; Olaiya, E O; Xella, S M; Aleksan, Roy; Emery, S; Gaidot, A; Ganzhur, S F; Giraud, P F; Hamel de Monchenault, G; Kozanecki, Witold; Langer, M; Legendre, M; London, G W; Mayer, B; Schott, G; Vasseur, G; Yéche, C; Zito, M; Purohit, M V; Weidemann, A W; Yumiceva, F X; Aston, D; Bartoldus, R; Berger, N; Boyarski, A M; Buchmüller, O L; Convery, M R; Cristinziani, M; Dong, D; Dorfan, J; Dujmic, D; Dunwoodie, W M; Elsen, E E; Field, R C; Glanzman, T; Gowdy, S J; Hadig, T; Halyo, V; Hrynóva, T; Innes, W R; Kelsey, M H; Kim, P; Kocian, M L; Leith, D W G S; Libby, J; Luitz, S; Lüth, V; Lynch, H L; Marsiske, H; Messner, R; Müller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Petrak, S; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Simi, G; Snyder, A; Soha, A; Stelzer, J; Su, D; Sullivan, M K; Vavra, J; Wagner, S R; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wright, D H; Young, C C; Burchat, Patricia R; Edwards, A J; Meyer, T I; Petersen, B A; Roat, C; Ahmed, M; Ahmed, S; Alam, M S; Ernst, J A; Saeed, M A; Saleem, M; Wappler, F R; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Kim, H; Ritchie, J L; Satpathy, A; Schwitters, R F; Izen, J M; Kitayama, I; Lou, X C; Ye, S; Bianchi, F; Bóna, M; Gallo, F; Gamba, D; Borean, C; Bosisio, L; Cossutti, F; Della Ricca, G; Dittongo, S; Grancagnolo, S; Lanceri, L; Poropat, P; Vitale, L; Vuagnin, G; Panvini, R S; Banerjee, Sw; Brown, C M; Fortin, D; Jackson, P D; Kowalewski, R V; Roney, J M; Band, H R; Dasu, S; Datta, M; Eichenbaum, A M; Johnson, J R; Kutter, P E; Li, H; Liu, R; Di Lodovico, F; Mihályi, A; Mohapatra, A K; Pan, Y; Prepost, R; Sekula, S J; Von Wimmersperg-Töller, J H; Wu, J; Wu Sau Lan; Yu, Z; Neal, H

    2003-01-01

    We have observed the rare decay B0 => rho+ rho- in a sample of 89 million BB pairs recorded with the BABAR detector. The number of observed events is 88 +23-21 +-9, with a significance of 5.1 standard deviations with systematic uncertainties included. The branching fraction and the longitudinal polarization are measured to be BR(B0 => rho+ rho-) = (25 +7-6 +5-6)*10^{-6} and Gamma_L/Gamma = 0.98 +0.02-0.08 +-0.03, respectively.

  9. Measurement of branching fractions and charge asymmetries for two-body B meson decays with charmonium

    CERN Document Server

    Aubert, B; Boutigny, D; Couderc, F; Karyotakis, Yu; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Graugès-Pous, E; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, Michael T; Wenzel, W A; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Fritsch, M; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Schröder, T; Steinke, M; Boyd, J T; Chevalier, N; Cottingham, W N; Kelly, M P; Latham, T E; Wilson, F F; Çuhadar-Dönszelmann, T; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Thiessen, D; Khan, A; Kyberd, P; Teodorescu, L; Blinov, A E; Blinov, V E; Druzhinin, V P; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bruinsma, M; Chao, M; Eschrich, I; Kirkby, D; Lankford, A J; Mandelkern, M A; Mommsen, R K; Röthel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Weinstein, A J R; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Del Re, D; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Eisner, A M; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S M; Mancinelli, G; Meadows, B T; Sokoloff, M D; Blanc, F; Bloom, P; Chen, S; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Ruddick, W O; Smith, J G; Ulmer, K A; Zhang, J; Zhang, L; Chen, A; Eckhart, E A; Harton, J L; Soffer, A; Toki, W H; Wilson, R J; Zeng, Q; Spaan, B; Altenburg, D; Brandt, T; Brose, J; Dickopp, M; Feltresi, E; Hauke, A; Lacker, H M; Nogowski, R; Otto, S; Petzold, A; Schubert, J; Schubert, Klaus R; Schwierz, R; Sundermann, J E; Bernard, D; Bonneaud, G R; Grenier, P; Schrenk, S; Thiebaux, C; Vasileiadis, G; Verderi, M; Bard, D J; Clark, P J; Muheim, F; Playfer, S; Xie, Y; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Sarti, A; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; De Sangro, R; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Won, E; Dubitzky, R S; Langenegger, U; Marks, J; Uwer, U; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Gaillard, J R; Morton, G W; Nash, J A; Nikolich, M B; Taylor, G P; Charles, M J; Grenier, G J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Yi, J; Arnaud, N; Davier, M; Giroux, X; Grosdidier, G; Höcker, A; Le Diberder, F R; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Wormser, G; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Chavez, C A; Coleman, J P; Forster, I J; Fry, J R; Gabathuler, Erwin; Gamet, R; Hutchcroft, D E; Parry, R J; Payne, D J; Touramanis, C; Cormack, C M; Di Lodovico, F; Brown, C L; Cowan, G; Flack, R L; Flächer, H U; Green, M G; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Hodgkinson, M C; Lafferty, G D; Williams, J C; Chen, C; Farbin, A; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Saremi, S; Stängle, H; Willocq, S; Cowan, R; Koeneke, K; Sciolla, G; Sekula, S J; Taylor, F; Yamamoto, R K; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L M; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Nicholson, H; Cavallo, N; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Bulten, H; Raven, G; Snoek, H L; Wilden, L; Jessop, C P; LoSecco, J M; Allmendinger, T; Benelli, G; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pulliam, T; Rahimi, A M; Ter-Antonian, R; Wong, Q K; Brau, J E; Frey, R; Igonkina, O; Lu, M; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; La Vaissière, C de; Del Buono, L; Hamon, O; John, M J J; Leruste, P; Malcles, J; Ocariz, J; Roos, L; Therin, G; Behera, P K; Gladney, L; Guo, Q H; Panetta, J; Biasini, M; Covarelli, R; Pioppi, M; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Bucci, F; Calderini, G; Carpinelli, M; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Morganti, M; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Simi, G; Walsh, J; Haire, M; Judd, D; Paick, K; Wagoner, D E; Danielson, N; Elmer, P; Lau, Y P; Lü, C; Miftakov, V; Olsen, J; Smith, A J S; Telnov, A V; Bellini, F; Cavoto, G; D'Orazio, A; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Li Gioi, L; Mazzoni, M A; Morganti, S; Pierini, M; Piredda, G; Polci, F; Safai-Tehrani, F; Voena, C; Christ, S; Schröder, H; Wagner, G; Waldi, R; Adye, T; De Groot, N; Franek, B J; Gopal, G P; Olaiya, E O; Aleksan, Roy; Emery, S; Gaidot, A; Ganzhur, S F; Giraud, P F; Hamel de Monchenault, G; Kozanecki, Witold; Legendre, M; London, G W; Mayer, B; Schott, G; Vasseur, G; Yéche, C; Zito, M; Purohit, M V; Weidemann, A W; Wilson, J R; Yumiceva, F X; Abe, T; Allen, M; Aston, D; Bartoldus, R; Berger, N; Boyarski, A M; Buchmüller, O L; Claus, R; Convery, M R; Cristinziani, M; De Nardo, Gallieno; Dingfelder, J C; Dong, D; Dorfan, J; Dujmic, D; Dunwoodie, W M; Fan, S; Field, R C; Glanzman, T; Gowdy, S J; Hadig, T; Halyo, V; Hast, C; Hrynóva, T; Innes, W R; Kelsey, M H; Kim, P; Kocian, M L; Leith, D W G S; Libby, J; Luitz, S; Lüth, V; Lynch, H L; Marsiske, H; Messner, R; Müller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Soha, A; Stelzer, J; Strube, J; Su, D; Sullivan, M K; Thompson, J; Vavra, J; Wagner, S R; Weaver, M; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Young, C C; Burchat, Patricia R; Edwards, A J; Majewski, S A; Petersen, B A; Roat, C; Ahmed, M; Ahmed, S; Alam, M S; Ernst, J A; Saeed, M A; Saleem, M; Wappler, F R; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Kim, H; Ritchie, J L; Satpathy, A; Schwitters, R F; Izen, J M; Kitayama, I; Lou, X C; Ye, S; Bianchi, F; Bóna, M; Gallo, F; Gamba, D; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Dittongo, S; Grancagnolo, S; Lanceri, L; Poropat, P; Vuagnin, G; Martínez-Vidal, F; Panvini, R S; Banerjee, Sw; Bhuyan, B; Brown, C M; Fortin, D; Jackson, P D; Kowalewski, R V; Roney, J M; Sobie, R J; Back, J J; Harrison, P F; Mohanty, G B; Band, H R; Chen, X; Cheng, B; Dasu, S; Datta, M; Eichenbaum, A M; Flood, K T; Graham, M; Hollar, J J; Johnson, J R; Kutter, P E; Li, H; Liu, R; Mihályi, A; Pan, Y; Prepost, R; Tan, P; Von Wimmersperg-Töller, J H; Wu, J; Wu, S L; Yu, Z; Greene, M G; Neal, H

    2003-01-01

    We report measurements of branching fractions and charge asymmetries of exclusive decays of neutral and charged B mesons into two-body final states containing a charmonium state and a light strange meson. The charmonium mesons considered are J/Psi, Psi(2S) and Chi_c1, and the light meson is either K or K*. We use a sample of about 124 million BBbar events collected with the BABAR detector at the PEP-II storage ring at the Stanford Linear Accelerator Center.

  10. Differential branching fraction and angular anaysis of Λb→Λμ+μ− decays

    CERN Multimedia

    Pescatore, Luca

    2015-01-01

    The differential branching fraction of the rare decay Λ0b → Λμ+μ− is measured as a function of q2, the square of the dimuon invariant mass. The analysis is performed using data collected by the LHCb experiment, corresponding to an integrated luminosity of 3.0 fb−1. These include evidence for signal at dimuon masses below the square of the J/ψ mass with significance above 3σ. In the q2 intervals where the signal is observed, angular distributions are studied and the forward-backward asymmetries in the dimuon and hadron systems are measured for the first time.

  11. Measurement of the Branching Fractions of the Decays B -> Dbar^(*) D^(*) K

    OpenAIRE

    Poireau, V.

    2010-01-01

    We present a measurement of the branching fractions of the 22 decay channels B0 and B+ to Dbar^(*) D^(*) K, where Dbar^(*) and D^(*) are fully reconstructed. The B0 and B+ mesons are reconstructed in a sample of hadronic events for all the possible Dbar D K modes, namely B0 -> D^(*)- D^(*)0 K^+, D^(*)-D^(*)+ K^0, Dbar^(*)0 D^(*)0 K0 and B^+ -> Dbar^(*)0 D^(*)+ K0, Dbar^(*)0 D^(*)0 K+, D^(*)- D^(*)+ K+. The results are based on 423 fb-1 of data that contained 465 10^6 BBbar pairs collected at ...

  12. Branching Fraction for the Doubly-Cabibbo-Suppressed Decay D^+ to K^_ pi^0

    CERN Document Server

    Dytman, S; Savinov, V; Aquines, O; Li, Z; López, A; Mehrabyan, S S; Méndez, H; Ramírez, J; Huang, G S; Miller, D H; Pavlunin, V; Sanghi, B; Shipsey, I P J; Xin, B; Adams, G S; Anderson, M; Cummings, J P; Danko, I; Napolitano, J; He, Q; Insler, J; Muramatsu, H; Park, C S; Thorndike, E H; Yang, F; Coan, T E; Gao, Y S; Liu, F; Artuso, M; Blusk, S; Butt, J; Li, J; Menaa, N; Mountain, R; Nisar, S; Randrianarivony, K; Redjimi, R; Sia, R; Skwarnicki, T; Stone, S; Wang, J C; Zhang, K; Csorna, S E; Bonvicini, G; Cinabro, D; Dubrovin, M; Lincoln, A; Asner, D M; Edwards, K W; Briere, R A; Brock, I; Chen, J; Ferguson, T; Tatishvili, G T; Vogel, H; Watkins, M E; Rosner, J L; Adam, N E; Alexander, J P; Berkelman, K; Cassel, D G; Duboscq, J E; Ecklund, K M; Ehrlich, R; Fields, L; Gibbons, L; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Mahlke-Krüger, H; Onyisi, P U E; Patterson, J R; Peterson, D; Pivarski, J; Riley, D; Ryd, A; Sadoff, A J; Schwarthoff, H; Shi, X; Stroiney, S; Sun, W M; Wilksen, T; Weinberger, M; Athar, S B; Patel, R; Potlia, V; Yelton, J; Rubin, P; Cawlfield, C; Eisenstein, B I; Karliner, I; Kim, D; Lowrey, N; Naik, P; Sedlack, C; Selen, M; White, E J; Wiss, J; Shepherd, M R; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Gong, D T; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Poling, R; Scott, A W; Smith, A; Zweber, P; Dobbs, S; Metreveli, Z V; Seth, K K; Tomaradze, A G; Ernst, J; Severini, H

    2006-01-01

    We present a measurement of the branching fraction for the doubly-Cabibbo-suppressed decay D+ to K+ pi0, using 281 pb-1 of data accumulated with the CLEO-c detector on the psi(3770) resonance. We find B(D+ to K+ pi0) = (2.25 +- 0.36 +- 0.15 +- 0.07) times 10^{-4}, where the first uncertainty is statistical, the second is systematic, and the last error is due to the uncertainty in the reference mode. The results presented in this document are preliminary.

  13. Measurement of the branching for the decay Ks → πeυ

    International Nuclear Information System (INIS)

    It is presented a measurement of the branching ratio BR (K → π± e ±v(v)) performed using the KLOW detector. Ks-mesons are produced in the reaction e±e± → φ → KSKL at the DAΦNE collider. In a sample of ∼ 5 x 106 Kstagged events it is found 624 ± 30 semileptonic Ks decays. Normalizing to the Ks → π+ π- count in the same data sample, it is obtained BR (Ks → π e υ) = (6.91 ± 0.37) x 10-4, in agreement with the Standard Model expectation

  14. Branching Ratios of a Decay for Nuclei near Deformed Shell Closures

    Institute of Scientific and Technical Information of China (English)

    WANG Yan-Zhao; ZHANG Hong-Fei; DONG Jian-Min; SU Xin-Ning; ZUO Wei; LI Jun-Qing

    2009-01-01

    The generalized liquid drop model (GLDM) is extended to the region around deformed shell closure 270Hs by taking into account the excitation energy EI+ of the residual daughter nucleus and the centrifugal potential energy Vcen(r).The branching ratios of a decays from the ground state of a parent nucleus to the ground state 0+ of its deformed daughter nucleus and to the first excited state 2+ are calculated in the framework of the GLDM.The results support the proposal that a measurement of α spectroscopy is a feasible method to extract information on nuclear deformation of superheavy nuclei around the deformed nucleus 270 Hs.

  15. (Beta)-decay experiments and the unitarity of the CKM matrix

    Energy Technology Data Exchange (ETDEWEB)

    Garrett, P E

    2005-12-01

    The goal of this project was to perform very precise measurements of super-allowed Fermi {beta} decay in order to investigate a possible non-unitarity in the CKM matrix of the Standard Model of particle physics. Current data from 9 precisely measured {beta} decays indicated that the sum-of-squares of the first row of the CKM matrix differs from 1.0 at the 2.2{sigma} (or 98% confidence) level. If true, it would be the first firm indication of physics beyond the Standard Model--the model that has been the backbone of the worldwide physics community for more than 30 years. The physics goal of the project was to test and constrain the calculated correction factors that must be applied to the experimental data by performing measurements at the TRIUMF radioactive ion beam facility ISAC. Accurate and precise (precision goal >99.9%) half lives and decay branching ratios were measured for nuclei where different sets of calculated corrections give divergent results thereby allowing us to determine which theory, if any, gives the correct result. The LLNL contribution was to design and build the data acquisition system that will enable the experiments, and to provide theoretical calculations necessary for the interpretation of the results. The first planned measurement was {sup 34}Ar, to be followed by {sup 62}Ga and {sup 74}Rb. However, there were major problems in creating a suitable, intense beam of radioactive {sup 34}Ar. The collaboration decided to proceed with measurements on {sup 62}Ga and {sup 18}Ne. These experiments were performed in a series of measurements in the summer and fall of 2004. The LLNL team also is leading the effort to perform measurements on {sup 66}As and {sup 70}Br that are expected during 2006-2008. While the definitive experiments to meet the goals of the LDRD were not conducted during the funding period, the involvement in the radioactive program at TRIUMF has lead to a number of new initiatives, and has attracted new staff to LLNL. This LDRD has

  16. Beta-decay properties of Zr and Mo neutron-rich isotopes

    CERN Document Server

    Sarriguren, P

    2010-01-01

    Gamow-Teller strength distributions, beta-decay half-lives, and beta-delayed neutron emission are investigated in neutron-rich Zr and Mo isotopes within a deformed quasiparticle random-phase approximation. The approach is based on a self-consistent Skyrme Hartree-Fock mean field with pairing correlations and residual separable particle-hole and particle-particle forces. Comparison with recent measurements of half-lives stresses the important role that nuclear deformation plays in the description of beta-decay properties in this mass region.

  17. Searches for heavy neutrinos from 35S, 14C, and 63Ni beta decay

    International Nuclear Information System (INIS)

    We have searched for the effect of a neutrino of mass 17 keV/c2 in the beta decay of 35S with an apparatus incorporating a high resolution solid state detector and a super conducting solenoid. The experimental mixing probability of the 17keV neutrino is consistent with zero. The experimental sensitivity is verified by measurements with a mixed source of 35S and 14C, which artificially produces a distortion in the beta spectrum similar to that expected from the massive neutrino. Recently, we have performed similar searches in the beta decay of 14C and 63Ni. Results of these new measurements will be presented

  18. Neutron Interactions in the CUORE Neutrinoless Double Beta Decay Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Dolinski, M J

    2008-09-24

    Neutrinoless double beta decay (0{nu}DBD) is a lepton-number violating process that can occur only for a massive Majorana neutrino. The search for 0{nu}DBD is currently the only practical experimental way to determine whether neutrinos are identical to their own antiparticles (Majorana neutrinos) or have distinct particle and anti-particle states (Dirac neutrinos). In addition, the observation of 0{nu}DBD can provide information about the absolute mass scale of the neutrino. The Cuoricino experiment was a sensitive search for 0{nu}DBD, as well as a proof of principle for the next generation experiment, CUORE. CUORE will search for 0{nu}DBD of {sup 130}Te with a ton-scale array of unenriched TeO{sub 2} bolometers. By increasing mass and decreasing the background for 0{nu}DBD, the half-life sensitivity of CUORE will be a factor of twenty better than that of Cuoricino. The site for both of these experiments is the Laboratori Nazionali del Gran Sasso, an underground laboratory with 3300 meters water equivalent rock overburden and a cosmic ray muon attenuation factor of 10{sup -6}. Because of the extreme low background requirements for CUORE, it is important that all potential sources of background in the 0{nu}DBD peak region at 2530 keV are well understood. One potential source of background for CUORE comes from neutrons, which can be produced underground both by ({alpha},n) reactions and by fast cosmic ray muon interactions. Preliminary simulations by the CUORE collaboration indicate that these backgrounds will be negligible for CUORE. However, in order to accurately simulate the expected neutron background, it is important to understand the cross sections for neutron interactions with detector materials. In order to help refine these simulations, I have measured the gamma-ray production cross sections for interactions of neutrons on the abundant stable isotopes of Te using the GEANIE detector array at the Los Alamos Neutron Science Center. In addition, I have used

  19. Systematic investigation of novel decay branches of the scissors mode in gadolinium isotopes

    International Nuclear Information System (INIS)

    The isotopes 152,154,156Gd are located in a region of the nuclear chart where sudden changes in nuclear deformation occur as a function of particle number. New decay branches of the nuclear scissors mode at this shape phase transition were studied exploiting complementary experimental methods. M1 excitation strengths of Jπ=1+ states in 152,154Gd were measured using the method of nuclear resonance fluorescence. The summed M1 excitation strengths are sum B(M1)↑=0.46(9) μN2 in the case of 152Gd and sum B(M1)↑=3.12(35) μN2 in the case of 154Gd. Using γγ coincidence measurements following electron capture of the nuclei 152,154Tb, new decay branches of those 1+ states to 0+2,3, 2+2,3 und 1-1 states were identified. A nuclear resonance fluorescence experiment using quasi-monochromatic, linearly polarized photons showed that the Jπ=1+ state with the largest M1 excitation strength of the static deformed nucleus 156Gd also exhibits a decay to the first excited 0+ state. The new properties of the scissors mode were described within the Interacting Boson Model 2 and were used to set the parameters of the Majorana operator. The new parameter set for the description of 154Gd has a direct impact on calculations of nuclear matrix elements of the neutrino-less double β decay process of 154Sm to the 0+2 state of 154Gd. Here, the new parameter set yields a significant larger matrix element than previously thought.

  20. Is the non observation of neutrinoless double beta decay a question of sensitivity?

    International Nuclear Information System (INIS)

    The hypothetical neutrinoless double beta decay is possible only if the neutrino is a truly neutral particle and if it is massive. A truly neutral particle (e.g. a particle identical with its antiparticle) should have all its algebraic intrinsic properties equal to zero, in particular, its lepton number should be 0. Now, since the neutrino is a lepton, its lepton number should be 1. This contradiction would lead to conclude that neutrinoless double beta decay could not take place in nature. This conclusion is, up to now, in agreement with persistent failures to put this long sought hypothetical key decay into evidence despite huge efforts dedicated to this aim

  1. Is the non-observation of neutrinoless double beta decay a question of sensitivity?

    International Nuclear Information System (INIS)

    Hypothetical neutrinoless double beta decay is possible only if the neutrino is a truly neutral particle and if it is massive. A truly neutral particle (e.g. a particle identical with its antiparticle) should have all its algebraic intrinsic properties equal to zero, in particular, its lepton number should be 0. Now, since the neutrino is a lepton, its lepton number should be 1. This contradiction would lead one to conclude that neutrinoless double beta decay cannot take place in nature. This conclusion is, up to now, in agreement with persistent failures to find evidence for this long sought key hypothetical decay despite huge efforts dedicated to this aim. (author)

  2. Observation of Two-Neutrino Double-Beta Decay in Xe-136 with EXO-200

    Energy Technology Data Exchange (ETDEWEB)

    Ackerman, N.; /SLAC; Aharmim, B.; /Laurentian U.; Auger, M.; /Bern U.; Auty, D.J.; /Alabama U.; Barbeau, P.S.; Barry, K.; Bartoszek, L.; /Stanford U., Phys. Dept.; Beauchamp, E.; /Laurentian U.; Belov, V.; /Moscow, ITEP; Benitez-Medina, C.; /Colorado State U.; Breidenbach, M.; /SLAC; Burenkov, A.; /Moscow, ITEP; Cleveland, B.; /Laurentian U.; Conley, R.; Conti, E.; /SLAC; Cook, J.; /Massachusetts U., Amherst; Cook, S.; /Colorado State U.; Coppens, A.; /Carleton U.; Counts, I.; /Stanford U., Phys. Dept.; Craddock, W.; /SLAC; Daniels, T.; /Massachusetts U., Amherst /Moscow, ITEP /Maryland U. /Stanford U., Phys. Dept. /Alabama U. /Maryland U. /Moscow, ITEP /Stanford U., Phys. Dept. /Laurentian U. /Carleton U. /Colorado State U. /Laurentian U. /Munich, Tech. U. /Bern U. /SLAC /Bern U. /Carleton U. /Stanford U., Phys. Dept. /Carleton U. /Maryland U. /Colorado State U. /SLAC /Carleton U. /SLAC /Alabama U. /SLAC /Moscow, ITEP /Indiana U. /Stanford U., Phys. Dept. /Moscow, ITEP /Stanford U., Phys. Dept. /Massachusetts U., Amherst /Seoul U. /Carleton U. /Stanford U., Phys. Dept.; /more authors..

    2012-09-14

    We report the observation of two-neutrino double-beta decay in {sup 136}Xe with T{sub 1/2} = 2.11 {+-} 0.04(stat) {+-} 0.21(syst) x 10{sup 21} yr. This second-order process, predicted by the standard model, has been observed for several nuclei but not for {sup 136}Xe. The observed decay rate provides new input to matrix element calculations and to the search for the more interesting neutrinoless double-beta decay, the most sensitive probe for the existence of Majorana particles and the measurement of the neutrino mass scale.

  3. Experiments TGV I (double-beta decay of 48Ca) and TGV II (double-beta decay of 106Cd and 48Ca)

    Science.gov (United States)

    Štekl, I.; Čermák, P.; Beneš, P.; Brudanin, V. B.; Rukhadze, N. I.; Egorov, V. G.; Kovalenko, V. E.; Kovalík, A.; Salamatin, A. V.; Tsoupko-Sitnikov, V. V.; Vylov, Ts.; Briancon, Ch.; Šimkovic, F.

    2000-04-01

    Present status of experiments TGV I and TGV II is given. The TGV I collaboration has studied the double-beta decay of 48Ca with a low-background and high sensitivity Ge multi-detector spectrometer TGV (Telescope Germanium Vertical). The preliminary results of years and years (90% CL) for double-beta decay of 48 Ca has been found after the processing of experimental data obtained after 8700 hours of measuring time using approximately 1 gramme of 48Ca. The aim of the experiment TGV II is the development of the experimental methods, construction of spectrometers and measurement of the decay (++, β+/EC, EC/EC) of 106Cd particularly the 2νEC/EC mode. The theoretical description and performance of the TGV II spectrometer are also given.

  4. Search for the ''missing'' α-decay branch in 239Cm

    International Nuclear Information System (INIS)

    A search for the α-decay of 239Cm was carried out via the fusion reaction 232Th(12C, 5n)239Cm at GSI, applying nuclear chemistry techniques. The 239Cm α-decay would provide a link between known nuclear masses and α-decay energies measured in the region of the superheavy elements. Three different 12C beam energies were chosen in the present experiments. The α peaks of 238,240Cm were observed clearly at a 12C energy of 74 MeV, while 238Cm disappeared at 70 MeV to provide an undisturbed α-spectrum for a sensitive search of 239Cm decay. No α-events between 6.34 and 6.50 MeV, which could be assigned to 239Cm with confidence, were observed in this experiment. The upper limit of the α-branch of 239Cm was less than 1.0 x 10-5. (orig.)

  5. The Gerda experiment for the search of 0{nu}{beta}{beta} decay in {sup 76}Ge

    Energy Technology Data Exchange (ETDEWEB)

    Ackermann, K.H.; Altmann, M.; Becerici-Schmidt, N.; Caldwell, A.; Cossavella, F.; Lenz, D.; Liao, H.; Majorovits, B.; Mayer, S.; O' Shaughnessy, C.; Schubert, J.; Schulz, O.; Seitz, H.; Stelzer, F.; Vogt, S.; Volynets, O. [Max-Planck-Institut fuer Physik, Muenchen (Germany); Agostini, M.; Bode, T.; Budjas, D.; Janicsko Csathy, J.; Lazzaro, A.; Schoenert, S. [Technische Universitaet Muenchen, Physik Department and Excellence Cluster Universe, Munich (Germany); Allardt, M.; Barros, N.; Domula, A.; Lehnert, B.; Zuber, K. [Technische Universitaet Dresden, Institut fuer Kern- und Teilchenphysik, Dresden (Germany); Andreotti, E. [Institute for Reference Materials and Measurements, Geel (Belgium); Eberhard Karls Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); Bakalyarov, A.M.; Belyaev, S.T.; Lebedev, V.I.; Zhukov, S.V. [National Research Centre ' ' Kurchatov Institute' ' , Moscow (Russian Federation); Balata, M.; Ioannucci, L.; Junker, M.; Laubenstein, M.; Nisi, S.; Pandola, L. [LNGS, INFN Laboratori Nazionali del Gran Sasso, Assergi (Italy); Barabanov, I.; Bezrukov, L.; Denisov, A.; Gurentsov, V.; Kianovsky, S.; Kusminov, V.; Lubsandorzhiev, B.; Yanovich, E. [Institute for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation); Barnabe Heider, M. [Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Technische Universitaet Muenchen, Physik Department and Excellence Cluster Universe, Munich (Germany); CEGEP St-Hyacinthe, Quebec (Canada); Baudis, L.; Benato, G.; Ferella, A.; Froborg, F.; Guthikonda, K.K.; Tarka, M.; Walter, M. [Physik Institut der Universitaet Zuerich, Zuerich (Switzerland); Bauer, C.; Hampel, W.; Heisel, M.; Heusser, G.; Hofmann, W.; Kankanyan, R.; Kihm, T.; Kiko, J.; Kirsch, A.; Knoepfle, K.T.; Lindner, M.; Lubashevskiy, A.; Machado, A.A.; Maneschg, W.; Oehm, J.; Salathe, M.; Schreiner, J.; Schwan, U.; Schwingenheuer, B.; Simgen, H.; Smolnikov, A.; Strecker, H.; Wagner, V.; Wegmann, A. [Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Bellotti, E. [Universita Milano Bicocca, Dipartimento di Fisica, Milano (Italy); INFN Milano Bicocca, Milano (Italy); Belogurov, S.; Kornoukhov, V.N. [Institute for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation); Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Bettini, A.; Brugnera, R.; Garfagnini, A.; Hemmer, S.; Sada, C. [Dipartimento di Fisica e Astronomia dell' Universita di Padova, Padova (Italy); INFN Padova, Padova (Italy); Brudanin, V.; Egorov, V.; Kochetov, O.; Nemchenok, I.; Shevchik, E.; Zhitnikov, I.; Zinatulina, D. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Cattadori, C. [INFN Milano Bicocca, Milano (Italy); Chernogorov, A.; Demidova, E.V.; Kirpichnikov, I.V.; Vasenko, A.A. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Chkvorets, O. [Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Laurentian University, Sudbury (Canada); D' Andragora, A. [LNGS, INFN Laboratori Nazionali del Gran Sasso, Assergi (Italy); Brookhaven National Laboratory, Upton, NY (United States); Di Vacri, A. [LNGS, INFN Laboratori Nazionali del Gran Sasso, Assergi (Italy); University ' ' G. d' Annunzio' ' di Chieti-Pescara, Department of Neurosciences and Imaging, Chieti (Italy); Falkenstein, R.; Freund, K.; Grabmayr, P.; Hegai, A.; Jochum, J.; Knapp, M.; Niedermeier, L.; Schmitt, C.; Sturm, K. von [Eberhard Karls Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); Frodyma, N.; Pelczar, K.; Wojcik, M.; Zuzel, G. [Jagiellonian University, Institute of Physics, Cracow (Poland); Gangapshev, A. [Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Institute for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation); Gasparro, J. [Institute for Reference Materials and Measurements, Geel (Belgium); National Physical Laboratory, Teddigton (United Kingdom); Gazzana, S. [LNGS, INFN Laboratori Nazionali del Gran Sasso, Assergi (Italy); Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Gonzalez de Orduna, R.; Hult, M.; Marissens, G. [Institute for Reference Materials and Measurements, Geel (Belgium); Gusev, K. [Joint Institute for Nuclear Research, Dubna (Russian Federation); National Research Centre ' ' Kurchatov Institute' ' , Moscow (Russian Federation); Technische Universitaet Muenchen, Physik Department and Excellence Cluster Universe, Munich (Germany); Inzhechik, L.V. [Institute for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation); Moscow Institute of Physics and Technology, Moscow (Russian Federation); Klimenko, A. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Institute for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation); Kroeninger, K. [Max-Planck-Institut fuer Physik, Muenchen (Germany); U. Goettingen, II. Physikalisches Institut, Goettingen (Germany); U. Siegen, Department Physik, Siegen (Germany); Lippi, I.; Rossi Alvarez, C.; Stanco, L.; Ur, C.A. [INFN Padova, Padova (Italy); Liu, J. [Max-Planck-Institut fuer Physik, Muenchen (Germany); University of Tokyo, Kavli IPMU, Tokyo (Japan); Liu, X. [Shanghai Jiaotong University, Shanghai (China); Meierhofer, G. [Eberhard Karls Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); TUeV-SUeD, Muenchen (Germany); Peiffer, P. [Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Pullia, A.; Riboldi, S. [Universita degli Studi di Milano (Italy); INFN Milano, Dipartimento di Fisica, Milano (Italy); Ritter, F. [Eberhard Karls Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); Robert Bosch GmbH, Reutlingen (Germany); Shirchenko, M. [Joint Institute for Nuclear Research, Dubna (Russian Federation); National Research Centre ' ' Kurchatov Institute' ' , Moscow (Russian Federation); Trunk, U. [Max Planck Institut fuer Kernphysik, Heidelberg (Germany); DESY, Photon-Science Detector Group, Hamburg (Germany); Zavarise, P. [LNGS, INFN Laboratori Nazionali del Gran Sasso, Assergi (Italy); University of L' Aquila, Dipartimento di Fisica, L' Aquila (Italy)

    2013-03-15

    The Gerda collaboration is performing a search for neutrinoless double beta decay of {sup 76}Ge with the eponymous detector. The experiment has been installed and commissioned at the Laboratori Nazionali del Gran Sasso and has started operation in November 2011. The design, construction and first operational results are described, along with detailed information from the R and D phase. (orig.)

  6. Determination of $\\gamma$ and $-2\\beta_s$ from charmless two-body decays of beauty mesons

    CERN Document Server

    Aaij, Roel; Adeva, Bernardo; Adinolfi, Marco; Affolder, Anthony; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Anderson, Jonathan; Andreassen, Rolf; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Belogurov, Sergey; Belous, Konstantin; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bien, Alexander; Bifani, Simone; Bird, Thomas; Bizzeti, Andrea; Bjørnstad, Pål Marius; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borgia, Alessandra; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Brambach, Tobias; Bressieux, Joël; Brett, David; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Brook, Nicholas; Brown, Henry; Bursche, Albert; Busetto, Giovanni; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Campana, Pierluigi; Campora Perez, Daniel; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chiapolini, Nicola; Chrzaszcz, Marcin; Ciba, Krzystof; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cojocariu, Lucian; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombes, Matthew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Counts, Ian; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dalseno, Jeremy; David, Pascal; David, Pieter; Davis, Adam; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Silva, Weeraddana; De Simone, Patrizia; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Di Canto, Angelo; Dijkstra, Hans; Donleavy, Stephanie; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dossett, David; Dovbnya, Anatoliy; Dreimanis, Karlis; Dujany, Giulio; Dupertuis, Frederic; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farinelli, Chiara; Farley, Nathanael; Farry, Stephen; Fay, Robert; Ferguson, Dianne; Fernandez Albor, Victor; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fol, Philip; Fontana, Marianna; Fontanelli, Flavio; Forty, Roger; Francisco, Oscar; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; García Pardiñas, Julián; Garofoli, Justin; Garra Tico, Jordi; Garrido, Lluis; Gaspar, Clara; Gauld, Rhorry; Gavardi, Laura; Gavrilov, Gennadii; Geraci, Angelo; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianelle, Alessio; Gianì, Sebastiana; Gibson, Valerie; Giubega, Lavinia-Helena; Gligorov, Vladimir; Göbel, Carla; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gotti, Claudio; Grabalosa Gándara, Marc; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graziani, Giacomo; Grecu, Alexandru; Greening, Edward; Gregson, Sam; Griffith, Peter; Grillo, Lucia; Grünberg, Oliver; Gui, Bin; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hall, Samuel; Hamilton, Brian; Hampson, Thomas; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; He, Jibo; Head, Timothy; Heijne, Veerle; Hennessy, Karol; Henrard, Pierre; Henry, Louis; Hernando Morata, Jose Angel; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hoballah, Mostafa; Hombach, Christoph; Hulsbergen, Wouter; Hunt, Philip; Hussain, Nazim; Hutchcroft, David; Hynds, Daniel; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jaton, Pierre; Jawahery, Abolhassan; Jing, Fanfan; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kaballo, Michael; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Karbach, Moritz; Karodia, Sarah; Kelsey, Matthew; Kenyon, Ian; Ketel, Tjeerd; Khanji, Basem; Khurewathanakul, Chitsanu; Klaver, Suzanne; Klimaszewski, Konrad; Kochebina, Olga; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Korolev, Mikhail; Kozlinskiy, Alexandr; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krocker, Georg; Krokovny, Pavel; Kruse, Florian; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kurek, Krzysztof; Kvaratskheliya, Tengiz; La Thi, Viet Nga; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lambert, Dean; Lambert, Robert W; Lanfranchi, Gaia; Langenbruch, Christoph; Langhans, Benedikt; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Lefèvre, Regis; Leflat, Alexander; Lefrançois, Jacques; Leo, Sabato; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Likhomanenko, Tatiana; Liles, Myfanwy; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Lohn, Stefan; Longstaff, Iain; Lopes, Jose; Lopez-March, Neus; Lowdon, Peter; Lu, Haiting; Lucchesi, Donatella; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Machefert, Frederic; Machikhiliyan, Irina V; Maciuc, Florin; Maev, Oleg; Malde, Sneha; Malinin, Alexander; Manca, Giulia; Mancinelli, Giampiero; Mapelli, Alessandro; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Märki, Raphael; Marks, Jörg; Martellotti, Giuseppe; Martens, Aurelien; Martín Sánchez, Alexandra; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massafferri, André; Matev, Rosen; Mathe, Zoltan; Matteuzzi, Clara; Mazurov, Alexander; McCann, Michael; McCarthy, James; McNab, Andrew; McNulty, Ronan; McSkelly, Ben; Meadows, Brian; Meier, Frank; Meissner, Marco; Merk, Marcel; Milanes, Diego Alejandro; Minard, Marie-Noelle; Moggi, Niccolò; Molina Rodriguez, Josue; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Müller, Katharina; Mussini, Manuel; Muster, Bastien; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Anh Duc; Nguyen, Thi-Dung; Nguyen-Mau, Chung; Nicol, Michelle; Niess, Valentin; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Oggero, Serena; Ogilvy, Stephen; Okhrimenko, Oleksandr; Oldeman, Rudolf; Onderwater, Gerco; Orlandea, Marius; Otalora Goicochea, Juan Martin; Owen, Patrick; Oyanguren, Maria Arantza; Pal, Bilas Kanti; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Panman, Jacob; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Parkes, Christopher; Parkinson, Christopher John; Passaleva, Giovanni; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pazos Alvarez, Antonio; Pearce, Alex; Pellegrino, Antonio; Pepe Altarelli, Monica; Perazzini, Stefano; Perez Trigo, Eliseo; Perret, Pascal; Perrin-Terrin, Mathieu; Pescatore, Luca; Pesen, Erhan; Petridis, Konstantin; Petrolini, Alessandro; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pilař, Tomas; Pinci, Davide; Pistone, Alessandro; Playfer, Stephen; Plo Casasus, Maximo; Polci, Francesco; Poluektov, Anton; Polycarpo, Erica; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Potterat, Cédric; Price, Eugenia; Price, Joseph David; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Rachwal, Bartolomiej; Rademacker, Jonas; Rakotomiaramanana, Barinjaka; Rama, Matteo; Rangel, Murilo; Raniuk, Iurii; Rauschmayr, Nathalie; Raven, Gerhard; Redi, Federico; Reichert, Stefanie; Reid, Matthew; dos Reis, Alberto; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vincente; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Perez, Pablo; Roiser, Stefan; Romanovsky, Vladimir; Romero Vidal, Antonio; Rotondo, Marcello; Rouvinet, Julien; Ruf, Thomas; Ruiz, Hugo; Ruiz Valls, Pablo; Saborido Silva, Juan Jose; Sagidova, Naylya; Sail, Paul; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santovetti, Emanuele; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrie, Mauro; Savrina, Darya; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Seco, Marcos; Semennikov, Alexander; Sepp, Indrek; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shires, Alexander; Silva Coutinho, Rafael; Simi, Gabriele; Sirendi, Marek; Skidmore, Nicola; Skwarnicki, Tomasz; Smith, Anthony; Smith, Edmund; Smith, Eluned; Smith, Jackson; Smith, Mark; Snoek, Hella; Sokoloff, Michael; Soler, Paul; Soomro, Fatima; Souza, Daniel; Souza De Paula, Bruno; Spaan, Bernhard; Sparkes, Ailsa; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Steinkamp, Olaf; Stenyakin, Oleg; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Stroili, Roberto; Subbiah, Vijay Kartik; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Swientek, Stefan; Syropoulos, Vasileios; Szczekowski, Marek; Szczypka, Paul; Szilard, Daniela; Szumlak, Tomasz; T'Jampens, Stephane; Teklishyn, Maksym; Tellarini, Giulia; Teubert, Frederic; Thomas, Christopher; Thomas, Eric; van Tilburg, Jeroen; Tisserand, Vincent; Tobin, Mark; Tolk, Siim; Tomassetti, Luca; Topp-Joergensen, Stig; Torr, Nicholas; Tournefier, Edwige; Tourneur, Stephane; Tran, Minh Tâm; Tresch, Marco; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tuning, Niels; Ubeda Garcia, Mario; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagnoni, Vincenzo; Valenti, Giovanni; Vallier, Alexis; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vázquez Sierra, Carlos; Vecchi, Stefania; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Vesterinen, Mika; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Vilasis-Cardona, Xavier; Vollhardt, Achim; Volyanskyy, Dmytro; Voong, David; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; Voss, Helge; de Vries, Jacco; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wandernoth, Sebastian; Wang, Jianchun; Ward, David; Watson, Nigel; Websdale, David; Whitehead, Mark; Wicht, Jean; Wiedner, Dirk; Wilkinson, Guy; Williams, Matthew; Williams, Mike; Wilschut, Hans; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wright, Simon; Wyllie, Kenneth; Xie, Yuehong; Xing, Zhou; Xu, Zhirui; Yang, Zhenwei; Yuan, Xuhao; Yushchenko, Oleg; Zangoli, Maria; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Wen Chao; Zhang, Yanxi; Zhelezov, Alexey; Zhokhov, Anatoly; Zhong, Liang; Zvyagin, Alexander

    2015-01-01

    Using the latest LHCb measurements of time-dependent $C\\!P$ violation in the $B^0_s \\to K^+K^-$ decay, a U-spin relation between the decay amplitudes of $B^0_s \\to K^+K^-$ and $B^0\\to \\pi^+\\pi^-$ decay processes allows constraints to be placed on the angle $\\gamma$ of the unitarity triangle and on the $B^0_s$ mixing phase $-2\\beta_s$. Results from an extended approach, which uses additional inputs on $B^0\\to \\pi^0\\pi^0$ and $B^+\\to \\pi^+\\pi^0$ decays from other experiments and exploits isospin symmetry, are also presented. The dependence of the results on the maximum allowed amount of U-spin breaking is studied. At 68% probability, the value $\\gamma = \\left( 63.5^{\\,+\\, 7.2}_{\\,-\\,6.7} \\right)^\\circ~\\mathrm{modulo}~180^\\circ$ is determined. In an alternative analysis, the value $-2\\beta_s = -0.12 ^{\\,+\\,0.14}_{\\,-\\,0.16}\\,\\,\\mathrm{rad}$ is found. In both measurements, the uncertainties due to U-spin breaking effects up to 50% are included.

  7. The Majorana Demonstrator: A Search for Neutrinoless Double-beta Decay of 76Ge

    CERN Document Server

    Xu, W; Avignone, F T; Barabash, A S; Bertrand, F E; Brudanin, V; Busch, M; Buuck, M; Byram, D; Caldwell, A S; Chan, Y-D; Christofferson, C D; Cuesta, C; Detwiler, J A; Efremenko, Yu; Ejiri, H; Elliott, S R; Galindo-Uribarri, A; Giovanetti, G K; Goett, J; Green, M P; Gruszko, J; Guinn, I; Guiseppe, V E; Henning, R; Hoppe, E W; Howard, S; Howe, M A; Jasinski, B R; Keeter, K J; Kidd, M F; Konovalov, S I; Kouzes, R T; LaFerriere, B D; Leon, J; MacMullin, J; Martin, R D; Meijer, S J; Mertens, S; Orrell, J L; O'Shaughnessy, C; Overman, N R; Poon, A W P; Radford, D C; Rager, J; Rielage, K; Robertson, R G H; Romero-Romero, E; Ronquest, M C; Shanks, B; Shirchenko, M; Snyder, N; Suriano, A M; Tedeschi, D; Trimble, J E; Varner, R L; Vasilyev, S; Vetter, K; Vorren, K; White, B R; Wilkerson, J F; Wiseman, C; Yakushev, E; Yu, C-H; Yumatov, V

    2015-01-01

    Neutrinoless double-beta decay is a hypothesized process where in some even-even nuclei it might be possible for two neutrons to simultaneously decay into two protons and two electrons without emitting neutrinos. This is possible only if neutrinos are Majorana particles, i.e. fermions that are their own antiparticles. Neutrinos being Majorana particles would explicitly violate lepton number conservation, and might play a role in the matter-antimatter asymmetry in the universe. The observation of neutrinoless double-beta decay would also provide complementary information related to neutrino masses. The Majorana Collaboration is constructing the Majorana Demonstrator, a 40-kg modular germanium detector array, to search for the Neutrinoless double-beta decay of 76Ge and to demonstrate a background rate at or below 3 counts/(ROI-t-y) in the 4 keV region of interest (ROI) around the 2039 keV Q-value for 76Ge Neutrinoless double-beta decay. In this paper, we discuss the physics of neutrinoless double beta decay and...

  8. ZnWO_4 crystals as detectors for double beta decay and dark matter experiments

    CERN Document Server

    Danevich, F A; Nagorny, S S; Poda, D V; Tretyak, V I; Yurchenko, S S; Zdesenko, Y G; Zdesenko, Yu.G.

    2004-01-01

    Energy resolution, alpha/beta ratio, and the pulse shape discrimination ability of the ZnWO_4 crystal scintillators were studied. The radioactive contamination of a ZnWO_4 crystal was investigated in the Solotvina Underground Laboratory. Possibilities to apply ZnWO_4 crystals for the dark matter and double beta decay searches are discussed. New improved half-life limits on double beta decay in zinc isotopes were established, in particular, for EC\\beta^+ decay of 64-Zn as: T_1/2^2nu > 8.9 10^18 yr and T_1/2^0nu > 3.6 10^18 yr, both at 68% CL.

  9. Neutrino propagation in nuclear medium and neutrinoless double-beta decay

    CERN Document Server

    Kovalenko, S; Simkovic, F

    2013-01-01

    We discuss a novel effect in neutrinoless double beta decay related with the fact that its underlying mechanisms take place in the nuclear matter environment. We study a particular case of neutrino exchange mechanism and demonstrate possible impact of nuclear medium via Lepton Number Violating (LNV) 4-fermion neutral current interactions of neutrino with quarks from decaying nucleus. The net effect of these interactions is generation of an effective in-medium Majorana neutrino mass matrix. We calculate the corresponding effective masses and construct the neutrino mixing matrix in nuclear medium for the complete set of the relevant 4-fermion neutrino-quark operators. Using the experimental data on neutrinoless double beta decay in combination with the cosmological and tritium beta decay data we evaluate lower limits on the characteristic scales of the studied 4-fermion operators. For the LNV scale we have > 2.4 TeV.

  10. Observation of Doppler broadening in $\\beta$-delayed proton-$\\gamma$ decay

    CERN Document Server

    Schwartz, S B; Bennett, M B; Liddick, S N; Perez-Loureiro, D; Bowe, A; Chen, A A; Chipps, K A; Cooper, N; Irvine, D; McNeice, E; Montes, F; Naqvi, F; Ortez, R; Pain, S D; Pereira, J; Prokop, C; Quaglia, J; Quinn, S J; Sakstrup, J; Santia, M; Shanab, S; Simon, A; Spyrou, A; Thiagalingam, E

    2015-01-01

    Background: The Doppler broadening of $\\gamma$-ray peaks due to nuclear recoil from $\\beta$-delayed nucleon emission can be used to measure the energies of the nucleons. This method has never been tested using $\\beta$-delayed proton emission or applied to a recoil heavier than $A=10$. Purpose: To test and apply this Doppler broadening method using $\\gamma$-ray peaks from the $^{26}$P($\\beta p\\gamma$)$^{25}$Al decay sequence. Methods: A fast beam of $^{26}$P was implanted into a planar Ge detector, which was used as a $^{26}$P $\\beta$-decay trigger. The SeGA array of high-purity Ge detectors was used to detect $\\gamma$ rays from the $^{26}$P($\\beta p\\gamma$)$^{25}$Al decay sequence. Results: Radiative Doppler broadening in $\\beta$-delayed proton-$\\gamma$ decay was observed for the first time. The Doppler broadening analysis method was verified using the 1613 keV $\\gamma$-ray line for which the proton energies were previously known. The 1776 keV $\\gamma$ ray de-exciting the 2720 keV $^{25}$Al level was observed...

  11. Probing the quenching of gA by single and double beta decays

    International Nuclear Information System (INIS)

    Ground-state-to-ground-state two-neutrino double beta (2νββ) decays and single beta (EC and β−) decays are studied for the A=100 (100Mo-100Tc-100Ru), A=116 (116Cd-116In-116Sn) and A=128 (128Te-128I-128Xe) nuclear systems by using the proton–neutron quasiparticle random-phase approximation exploiting realistic effective interactions in very large single-particle bases. The aim of this exercise is to see if both the single-beta and double-beta decay observables related to the ground states of the initial, intermediate and final nuclei participant in the decays can be described simultaneously by changing the value of the axial-vector coupling constant gA. In spite of the very different responses to single and 2νββ decays of the considered nuclear systems, the obtained results point consistently to a quenched effective value of gA that is (slightly) different for the single and 2νββ decays

  12. Sum rules for the gross theory of beta-decay

    International Nuclear Information System (INIS)

    This paper presents a method for relating the β-decay strength function with the nuclear force. This relation is obtained as sum rules for the one-particle strength function which appears in the gross theory of β-decay. They sum rules were calculated for the Gamow-Teller transition with some central potentials and the Hamada-Johnston potential. The sum-rule values were found to depend strongly on the assumed nuclear force

  13. Time reversal tests in nuclear and neutron beta decay

    International Nuclear Information System (INIS)

    Motivation for time reversal violation studies in nuclear and neutron weak decay is discussed with an emphasis on searches for the exotic tensor and scalar weak interaction. The results of the experiment with polarized 8Li are updated. A new experiment with the aim to determine the transverse polarization of electrons emitted by free, polarized neutrons, is proposed. A facility for neutron decay studies with polarized cold neutrons is under construction at the spallation source SINQ-PSI

  14. Limit on Neutrinoless {\\beta}{\\beta} Decay of Xe-136 from the First Phase of KamLAND-Zen and Comparison with the Positive Claim in Ge-76

    CERN Document Server

    ,

    2012-01-01

    We present results from the first phase of the KamLAND-Zen double-beta decay experiment, corresponding to an exposure of 89.5 kg-yr of Xe-136. We obtain a lower limit for the neutrinoless double-beta decay half-life of T_{1/2}^{0{\

  15. Searching for neutrinoless double-beta decay of {sup 130}Te with CUORE

    Energy Technology Data Exchange (ETDEWEB)

    CUORE,; Artusa, D. R.; Avignone III, F. T.; Azzolini, O.; Balata, M.; Banks, T. I.; Bari, G.; Beeman, J.; Bellini, F.; Bersani, A.; Biassoni, M.; Brofferio, C.; Bucci, C.; Cai, X. Z.; Camacho, A.; Canonica, L.; Cao, X. G.; Capelli, S.; Carbone, L.; Cardani, L.; Carrettoni, M.; Casali, N.; Chiesa, D.; Chott, N.; Clemenza, M.; Copello, S.; Cosmelli, C.; Cremonesi, O.; Creswick, R. J.; Dafinei, I.; Dally, A.; Datskov, V.; Biasi, A. De; Deninno, M. M.; Domizio, S. Di; Vacri, M. L. di; Ejzak, L.; Fang, D. Q.; Farach, H. A.; Faverzani, M.; Fernandes, G.; Ferri, E.; Ferroni, F.; Fiorini, E.; Franceschi, M. A.; Freedman, S. J.; Fujikawa, B. K.; Giachero, A.; Gironi, L.; Giuliani, A.; Goett, J.; Gorla, P.; Gotti, C.; Gutierrez, T. D.; Haller, E. E.; Han, K.; Heeger, K. M.; Hennings-Yeomans, R.; Huang, H. Z.; Kadel, R.; Kazkaz, K.; Keppel, G.; Kolomensky, Yu. G.; Li, Y. L.; Ligi, C.; Liu, X.; Ma, Y. G.; Maiano, C.; Maino, M.; Martinez, M.; Maruyama, R. H.; Mei, Y.; Moggi, N.; Morganti, S.; Napolitano, T.; Nisi, S.; Nones, C.; Norman, E. B.; Nucciotti, A.; O' Donnell, T.; Orio, F.; Orlandi, D.; Ouellet, J. L.; Pallavicini, M.; Palmieri, V.; Pattavina, L.; Pavan, M.; Pedretti, M.; Pessina, G.; Pettinacci, V.; Piperno, G.; Pira, C.; Pirro, S.; Previtali, E.; Rampazzo, V.; Rosenfeld, C.; Rusconi, C.; Sala, E.; Sangiorgio, S.; Scielzo, N. D.; Sisti, M.; Smith, A. R.; Taffarello, L.; Tenconi, M.; Terranova, F.; Tian, W. D.; Tomei, C.; Trentalange, S.; Ventura, G.; Vignati, M.; Wang, B. S.; Wang, H. W.; Wielgus, L.; Wilson, J.; Winslow, L. A.; Wise, T.; Woodcraft, A.; Zanotti, L.; Zarra, C.; Zhu, B. X.; Zucchelli, S.

    2014-02-24

    Neutrinoless double-beta (0{nu}{beta}{beta}) decay is a hypothesized lepton-number-violating process that offers the only known means of asserting the possible Majorana nature of neutrino mass. The Cryogenic Underground Observatory for Rare Events (CUORE) is an upcoming experiment designed to search for 0{nu}{beta}{beta} decay of {sup 130}Te using an array of 988 TeO{sub 2} crystal bolometers operated at 10 mK. The detector will contain 206 kg of {sup 130}Te and have an average energy resolution of 5 keV; the projected 0{nu}{beta}{beta} decay half-life sensitivity after five years of live time is 1.6 x 10{sup 26} y at 1{sigma} (9.5x10{sup 25} y at the 90% confidence level), which corresponds to an upper limit on the effective Majorana mass in the range 40-100 meV (50-130 meV). In this paper we review the experimental techniques used in CUORE as well as its current status and anticipated physics reach.

  16. Double Beta Decay Experiments: Present Status and Prospects for the Future

    Science.gov (United States)

    Barabash, A. S.

    The review of modern experiments on search and studying of double beta decay processes is done. Results of the most sensitive current experiments are discussed. The main attention is paid to EXO-200, KamLAND-Zen, GERDA-I and CUORE-0 experiments. Modern values of T1/2(2ν) and best present limits on neutrinoless double beta decay and double beta decay with Majoron emission are presented. Conservative limits on effective mass of a Majorana neutrino ( at the level of ∼ (0.01-0.1) eV are discussed. The main attention is paid to experiments of CUORE, GERDA, MAJORANA, EXO, KamLAND-Zen-2, SuperNEMO and SNO+. Possibilities of low-temperature scintillating bolometers on the basis of inorganic crystals (ZnSe, ZnMoO4, Li2MoO4, CaMoO4 and CdWO4) are considered too.

  17. First results of the search of neutrinoless double beta decay with the NEMO 3 detector

    CERN Document Server

    Arnold, R; Baker, J; Barabash, A; Broudin, G; Brudanin, V; Caffrey, A J; Caurier, E; Egorov, V; Errahmane, K; Etienvre, A I; Guyonnet, J L; Hubert, F; Hubert, P; Jollet, C; Jullian, S; Kochetov, O; Kovalenko, V; Konovalov, S; Lalanne, D; Leccia, F; Longuemare, C; Lutter, G; Marquet, C; Mauger, F; Nowacki, F; Ohsumi, H; Piquemal, F; Reyss, J L; Saakyan, R; Sarazin, X; Simard, L; Simkovic, F; Shitov, Y; Smolnikov, A A; Stekl, I; Suhonen, J; Sutton, C S; Szklarz, G; Thomas, J; Timkin, V; Tretyak, V; Umatov, V; Vàla, L; Vanyushin, I A; Vasilyev, V; Vorobel, V; Vylov, T D

    2005-01-01

    The NEMO 3 detector, which has been operating in the Frejus underground laboratory since February 2003, is devoted to the search for neutrinoless double beta decay (bb0nu). Half-lives of the two neutrino double beta decays (bb2nu) have been measured for 100Mo and 82Se. After 389 effective days of data collection from February 2003 until September 2004 (Phase I), no evidence for neutrinoless double beta decay was found from ~7kg of 100Mo and ~1 kg of 82Se. The corresponding lower limits for the half-lives are 4.6 x 10^23 years for 100Mo and 1.0 x10^23 years for 82Se (90% C.L.). Depending on the nuclear matrix elements calculation, limits for the effective Majorana neutrino mass are < 1.7-4.9 eV for 82Se

  18. The MAJORANA DEMONSTRATOR: A Search for Neutrinoless Double-beta Decay of Germanium-76

    CERN Document Server

    Schubert, A G; Avignone, F T; Back, H O; Barabash, A S; Bergevin, M; Bertrand, F E; Boswell, M; Brudanin, V; Busch, M; Chan, Y-D; Christofferson, C D; Collar, J I; Combs, D C; Cooper, R J; Detwiler, J A; Leon, J; Doe, P J; Efremenko, Yu; Egorov, V; Ejiri, H; Elliott, S R; Esterline, J; Fast, J E; Fields, N; Finnerty, P; Fraenkle, F M; Gehman, V M; Giovanetti, G K; Green, M P; Guiseppe, V E; Gusey, K; Hallin, A L; Hazama, R; Henning, R; Hime, A; Hoppe, E W; Horton, M; Howard, S; Howe, M A; Johnson, R A; Keeter, K J; Keillor, M E; Keller, C; Kephart, J D; Kidd, M F; Knecht, A; Kochetov, O; Konovalov, S I; Kouzes, R T; LaFerriere, B; LaRoque, B H; Leviner, L E; Loach, J C; MacMullin, S; Marino, M G; Martin, R D; Mei, D -M; Merriman, J; Miller, M L; Mizouni, L; Nomachi, M; Orrell, J L; Overman, N; Phillips, D G; Poon, A W P; Perumpilly, G; Prior, G; Radford, D C; Rielage, K; Robertson, R G H; Ronquest, M C; Shima, T; Shirchenko, M; Snavely, K J; Sobolev, V; Steele, D; Strain, J; Thomas, K; Timkin, V; Tornow, W; Vanyushin, I; Varner, R L; Vetter, K; Vorren, K; Wilkerson, J F; Wolfe, B A; Yakushev, E; Young, A R; Yu, C ?H; Yumatov, V; Zhan, C

    2011-01-01

    The observation of neutrinoless double-beta decay would determine whether the neutrino is a Majorana particle and provide information on the absolute scale of neutrino mass. The MAJORANA Collaboration is constructing the DEMONSTRATOR, an array of germanium detectors, to search for neutrinoless double-beta decay of 76-Ge. The DEMONSTRATOR will contain 40 kg of germanium; up to 30 kg will be enriched to 86% in 76-Ge. The DEMONSTRATOR will be deployed deep underground in an ultra-low-background shielded environment. Operation of the DEMONSTRATOR aims to determine whether a future tonne-scale germanium experiment can achieve a background goal of one count per tonne-year in a 4-keV region of interest around the 76-Ge neutrinoless double-beta decay Q-value of 2039 keV.

  19. Experimental study of double beta decay modes using a CdZnTe detector array

    CERN Document Server

    Dawson, J V; Janutta, B; Junker, M; Koettig, T; Münstermann, D; Rajek, S; Reeve, C; Schulz, O; Wilson, J R; Zuber, K

    2009-01-01

    An array of sixteen 1 cm^3 CdZnTe semiconductor detectors was operated at the Gran Sasso Underground Laboratory (LNGS) to further investigate the feasibility of double beta decay searches with such devices. As one of the double beta decay experiments with the highest granularity the 4 x 4 array accumulated an overall exposure of 18 kg days. The set-up and performance of the array is described. Half-life limits for various double beta decay modes of Cd, Zn and Te isotopes are obtained. No signal has been found, but several limits beyond 10^20 years have been performed. They are an order of magnitude better than those obtained with this technology before and comparable to most other experimental approaches for the isotopes under investigation.

  20. Measurement of CP Asymmetries and Branching Fractions in Charmless Two-Body B-Meson Decays to Pions and Kaons

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-06-18

    We present improved measurements of CP-violation parameters in the decays B{sup 0} {yields} {pi}{sup +}{pi}{sup -}, B{sup 0} {yields} K{sup +}{pi}{sup -}, and B{sup 0} {yields} {pi}{sup 0}{pi}{sup 0}, and of the branching fractions for B{sup 0} {yields} {pi}{sup 0}{pi}{sup 0} and B{sup 0} {yields} K{sup 0}{pi}{sup 0}. The results are obtained with the full data set collected at the {Upsilon}(4S) resonance by the BABAR experiment at the PEP-II asymmetric-energy B factory at the SLAC National Accelerator Laboratory, corresponding to 467 {+-} 5 million B{bar B} pairs. We find the CP-violation parameter values and branching fractions S{sub {pi}{sup +}{pi}{sup -}} = -0.68 {+-} 0.10 {+-} 0.03, C{sub {pi}{sup +}{pi}{sup -}} = -0.25 {+-} 0.08 {+-} 0.02, {Alpha}{sub K{sup -}{pi}{sup +}} = -0.107 {+-} 0.016{sub -0.004}{sup +0.006}, C{sub {pi}{sup 0}{pi}{sup 0}} = -0.43 {+-} 0.26 {+-} 0.05, {Beta}(B{sup 0} {yields} {pi}{sup 0}{pi}{sup 0}) = (1.83 {+-} 0.21 {+-} 0.13) x 10{sup -6}, {Beta}(B{sup 0} {yields} K0{pi}{sup 0}) = (10.1 {+-} 0.6 {+-} 0.4) x 10{sup -6}, where in each case, the first uncertainties are statistical and the second are systematic. We observe CP violation with a significance of 6.7 standard deviations for B{sup 0} {yields} {pi}{sup +}{pi}{sup -} and 6.1 standard deviations for B{sup 0} {yields} K{sup +}{pi}{sup -}, including systematic uncertainties. Constraints on the Unitarity Triangle angle {alpha} are determined from the isospin relations among the B {yields} {pi}{pi} rates and asymmetries. Considering only the solution preferred by the Standard Model, we find {alpha} to be in the range [71{sup o}, 109{sup o}] at the 68% confidence level.

  1. The Heidelberg-Moscow double beta decay experiment with enriched sup 76 Ge. First result

    Energy Technology Data Exchange (ETDEWEB)

    Balysh, A.; Belyaev, S.T.; Demehin, A.; Gurov, A.; Kondratenko, I.; Lebedev, V.I. (Max-Planck-Inst. fuer Kernphysik, Heidelberg (Germany)); Beck, M.; Bockholt, J.; Echternach, J.; Heusser, G.; Hirsch, M.; Klapdor-Kleingrothaus, H.V.; Maier, B.; Petry, F.; Piepke, A.; Schmidt-Rohr, U.; Strecker, H.; Zuber, K. (Kurchatov Inst., Moscow (USSR)); Mueller, A. (Ist. Nazionale di Fisica Nucleare, Assergi (Italy))

    1992-06-04

    The status of the Heidelberg-Moscow {beta}{beta}-experiment using isotopically enriched {sup 76}Ge is reported. The results of 14.8 mol yr (or 1.29 kg yr) of operation are presented. From these data a new half life time for the {beta}{beta}0{nu}-decay of {sup 76}Ge to the ground state of {sup 76}Se of T{sub 1/2}>1.4(2.5)x10{sup 24} yr with 90% (68%) CL can be deduced. For a possible neutrinoless decay to the first excited state a half life of 4.3(8.2)x10{sup 23} yr can be excluded with 90% (68%) CL. (orig.).

  2. Experimental study on neutrinoless double beta decay of 92Mo

    International Nuclear Information System (INIS)

    An experiment for the detection of 0νβ+/EC in 92Mo nuclei has been carried out with a newly developed scintillating crystal, CaMoO4, surrounded by CsI(Tl) crystals. We study the background events inside the event selection window for 0νβ+/EC decays of CaMoO4 detector. The 92Mo 0νβ+/EC decay half-life limit was set to 2.3x1020 years with a 90% confidence level. A perspective on the current experiment is discussed.

  3. Double beta decay: introduction, motivations and last results

    International Nuclear Information System (INIS)

    The double β decay process is the direct desexcitation from a nucleus (Z,A) to a nucleus (Z+2, A). Since long time ago, study of this process has been recognized as a very sensitive test of the lepton number non-conservation and therefore the double β decay process is strongly connected to the neutrino properties. This review starts with the main definitions and main motivations for such studies. Then the different experiments actually running and the most recent experimental results are exposed

  4. A novel radioguided surgery technique exploiting $\\beta^{-}$ decays

    CERN Document Server

    Camillocci, E Solfaroli; Bellini, F; Bocci, V; Collamati, F; Cremonesi, M; De Lucia, E; Ferroli, P; Fiore, S; Grana, C M; Marafini, M; Mattei, I; Morganti, S; Paganelli, G; Patera, V; Piersanti, L; Recchia, L; Russomando, A; Schiariti, M; Sarti, A; Sciubba, A; Voena, C; Faccini, R

    2014-01-01

    The background induced by the high penetration power of the gamma radiation is the main limiting factor of the current Radio-guided surgery (RGS). To partially mitigate it, a RGS with beta+ emitting radio-tracers has been suggested in literature. Here we propose the use of beta- emitting radio-tracers and beta- probes and discuss the advantage of this method with respect to the previously explored ones: the electron low penetration power allows for simple and versatile probes and could extend RGS to tumours for which background originating from nearby healthy tissue makes gamma probes less effective. We developed a beta- probe prototype and studied its performances on phantoms. By means of a detailed simulation we have also extrapolated the results to estimate the performances in a realistic case of meningioma, pathology which is going to be our first in-vivo test case. A good sensitivity to residuals down to 0.1ml can be reached within 1s with an administered activity smaller than those for PET-scans thus ma...

  5. ${\\beta}$-decay studies of neutron-rich $^{61-70}$Mn isotopes with the new LISOL ${\\beta}$-decay setup

    CERN Multimedia

    Diriken, J V J

    2008-01-01

    The aim of this proposal is to gather new information that will serve as benchmark to test shell model calculations in the region below $^{68}$Ni, where proper residual interactions are still under development. More specifically, the ${\\beta}$-decay experiment of the $^{61-70}$Mn isotopes will highlight the development of collectivity in the Fe isotopes and its daughters. At ISOLDE, neutron-rich Mn isotopes are produced with a UC$_{x}$ target and selective laser ionization. These beams are particularly pure and reasonable yields are obtained for the neutron-rich short lived $^{61-70}$Mn isotopes. We propose to perform ${\\beta}$-decay studies on $^{61-70}$Mn utilizing the newly-developed "LISOL ${\\beta}$-decay setup", consisting of two MINIBALL cluster Ge detectors and a standard tape station. The use of digital electronics in the readout of these detectors enables us to perform a "slow correlation technique" which should indicate the possible existence of isomers in the daughter nuclei.

  6. First observation of the decay Bs0-->Ds-Ds+ and measurement of its branching ratio.

    Science.gov (United States)

    Aaltonen, T; Adelman, J; Akimoto, T; Albrow, M G; Alvarez González, B; Amerio, S; Amidei, D; Anastassov, A; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Apresyan, A; Arisawa, T; Artikov, A; Ashmanskas, W; Attal, A; Aurisano, A; Azfar, F; Azzi-Bacchetta, P; Azzurri, P; Bacchetta, N; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Baroiant, S; Bartsch, V; Bauer, G; Beauchemin, P-H; Bedeschi, F; Bednar, P; Behari, S; Bellettini, G; Bellinger, J; Belloni, A; Benjamin, D; Beretvas, A; Beringer, J; Berry, T; Bhatti, A; Binkley, M; Bisello, D; Bizjak, I; Blair, R E; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bolla, G; Bolshov, A; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Bridgeman, A; Brigliadori, L; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Budd, S; Burkett, K; Busetto, G; Bussey, P; Buzatu, A; Byrum, K L; Cabrera, S; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carlsmith, D; Carosi, R; Carrillo, S; Carron, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chang, S H; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, K; Chokheli, D; Chou, J P; Choudalakis, G; Chuang, S H; Chung, K; Chung, W H; Chung, Y S; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Compostella, G; Convery, M E; Conway, J; Cooper, B; Copic, K; Cordelli, M; Cortiana, G; Crescioli, F; Cuenca Almenar, C; Cuevas, J; Culbertson, R; Cully, J C; Dagenhart, D; Datta, M; Davies, T; de Barbaro, P; De Cecco, S; Deisher, A; De Lentdecker, G; De Lorenzo, G; Dell'Orso, M; Demortier, L; Deng, J; Deninno, M; De Pedis, D; Derwent, P F; Di Giovanni, G P; Dionisi, C; Di Ruzza, B; Dittmann, J R; D'Onofrio, M; Donati, S; Dong, P; Donini, J; Dorigo, T; Dube, S; Efron, J; Erbacher, R; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, W T; Feild, R G; Feindt, M; Fernandez, J P; Ferrazza, C; Field, R; Flanagan, G; Forrest, R; Forrester, S; Franklin, M; Freeman, J C; Furic, I; Gallinaro, M; Galyardt, J; Garberson, F; Garcia, J E; Garfinkel, A F; Gerberich, H; Gerdes, D; Giagu, S; Giakoumopolou, V; Giannetti, P; Gibson, K; Gimmell, J L; Ginsburg, C M; Giokaris, N; Giordani, M; Giromini, P; Giunta, M; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Golossanov, A; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gresele, A; Grinstein, S; Grosso-Pilcher, C; Grundler, U; Guimaraes da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Hamilton, A; Han, B-Y; Han, J Y; Handler, R; Happacher, F; Hara, K; Hare, D; Hare, M; Harper, S; Harr, R F; Harris, R M; Hartz, M; Hatakeyama, K; Hauser, J; Hays, C; Heck, M; Heijboer, A; Heinemann, B; Heinrich, J; Henderson, C; Herndon, M; Heuser, J; Hewamanage, S; Hidas, D; Hill, C S; Hirschbuehl, D; Hocker, A; Hou, S; Houlden, M; Hsu, S-C; Huffman, B T; Hughes, R E; Husemann, U; Huston, J; Incandela, J; Introzzi, G; Iori, M; Ivanov, A; Iyutin, B; James, E; Jayatilaka, B; Jeans, D; Jeon, E J; Jindariani, S; Johnson, W; Jones, M; Joo, K K; Jun, S Y; Jung, J E; Junk, T R; Kamon, T; Kar, D; Karchin, P E; Kato, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kimura, N; Kirsch, L; Klimenko, S; Klute, M; Knuteson, B; Ko, B R; Koay, S A; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kraus, J; Kreps, M; Kroll, J; Krumnack, N; Kruse, M; Krutelyov, V; Kubo, T; Kuhlmann, S E; Kuhr, T; Kulkarni, N P; Kusakabe, Y; Kwang, S; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; Lecompte, T; Lee, J; Lee, J; Lee, Y J; Lee, S W; Lefèvre, R; Leonardo, N; Leone, S; Levy, S; Lewis, J D; Lin, C; Lin, C S; Linacre, J; Lindgren, M; Lipeles, E; Lister, A; Litvintsev, D O; Liu, T; Lockyer, N S; Loginov, A; Loreti, M; Lovas, L; Lu, R-S; Lucchesi, D; Lueck, J; Luci, C; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; Lytken, E; Mack, P; Macqueen, D; Madrak, R; Maeshima, K; Makhoul, K; Maki, T; Maksimovic, P; Malde, S; Malik, S; Manca, G; Manousakis, A; Margaroli, F; Marino, C; Marino, C P; Martin, A; Martin, M; Martin, V; Martínez, M; Martínez-Ballarín, R; Maruyama, T; Mastrandrea, P; Masubuchi, T; Mattson, M E; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Mehtala, P; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; Miao, T; Miladinovic, N; Miles, J; Miller, R; Mills, C; Milnik, M; Mitra, A; Mitselmakher, G; Miyake, H; Moed, S; Moggi, N; Moon, C S; Moore, R; Morello, M; Movilla Fernandez, P; Mülmenstädt, J; Mukherjee, A; Muller, Th; Mumford, R; Murat, P; Mussini, M; Nachtman, J; Nagai, Y; Nagano, A; Naganoma, J; Nakamura, K; Nakano, I; Napier, A; Necula, V; Neu, C; Neubauer, M S; Nielsen, J; Nodulman, L; Norman, M; Norniella, O; Nurse, E; Oh, S H; Oh, Y D

    2008-01-18

    We report the observation of the exclusive decay Bs0-->Ds-Ds+ at the 7.5 standard deviation level using 355 pb(-1) of data collected by the CDF II detector in pp collisions at sqrt[s]=1.96 TeV at the Fermilab Tevatron. We measure the relative branching ratio B(Bs0-->Ds-Ds+)/B(B0-->D-Ds+)=1.44(-0.44)(+0.48). Using the world average value for B(B0-->D-Ds+), we find B(Bs0-->Ds-Ds+)=(9.4(-4.2)(+4.4))x10(-3). This provides a lower bound DeltaGammasCP/Gammas>or=2B(Bs0-->Ds-Ds+)>1.2x10(-2) at 95% C.L. PMID:18232856

  7. Beta-decay properties of Zr and Mo neutron-rich isotopes

    OpenAIRE

    Sarriguren, P.; Pereira, J

    2010-01-01

    Gamow-Teller strength distributions, beta-decay half-lives, and beta-delayed neutron emission are investigated in neutron-rich Zr and Mo isotopes within a deformed quasiparticle random-phase approximation. The approach is based on a self-consistent Skyrme Hartree-Fock mean field with pairing correlations and residual separable particle-hole and particle-particle forces. Comparison with recent measurements of half-lives stresses the important role that nuclear deformation plays in the descript...

  8. Recent status of the studies of nuclear masses and {beta}-decay

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Masami [Waseda Univ., Tokyo (Japan). Advanced Research Center for Science and Engineering

    1996-05-01

    The recent status of the above studies was explained, especially, nuclear masses were described from the aspect of probability theory and that of {beta}-decay suggested that the first forbidden transition was hindered between the ground states. We have to study various systematics in order to know the mass surface, Way-Yamada-Matumoto type systematics is better to check the experimental nuclear masses. The gross theory is very useful to understand the general aspect of {beta}-decay. The understanding method of mass surface, systematic check of mass and hindrance of the first forbidden transition at rank 1 were explained. (S.Y.)

  9. Double-beta decay of 48Ca in the TGV experiment

    International Nuclear Information System (INIS)

    The low-background, high-sensitivity Ge multidetector spectrometer TGV is used to study the double-beta decay of 48Ca. Additional suppression of the recorded background is achieved with neutron shielding and a method for distinguishing β particles from γ rays by detector-pulse rise time. The estimates T1sol2ββ2v= (4.2 ± 2.4) x 1019 yr and T1sol2ββ0v > 1.5 x 1021 yr (at a 90% C.L.) for the double-beta decay of 48Ca are obtained

  10. Search for double beta decay of 48Ca in the TGV experiment

    Science.gov (United States)

    Brudanin, V. B.; Rukhadze, N. I.; Briançon, C.; Egorov, V. G.; Kovalenko, V. E.; Kovalik, A.; Salamatin, A. V.; Štekl, I.; Tsoupko-Sitnikov, V. V.; Vylov, T.; Čermák, P.

    2000-12-01

    This Letter describes a collaborative TGV (Telescope Germanium Vertical) study of the double beta decay of 48Ca with a low-background and high sensitivity Ge multi-detector spectrometer. The results of T1/22νββ=(4.2+3.3- 1.3)×1019 years and T1/20νββ>1.5×1021 years (90% CL) for double beta decay of 48Ca were found after processing experimental data obtained after 8700 hours of measuring time, using approximately 1 gramme of 48Ca. The features of a TGV-2 experiment are also presented.

  11. Double-beta decay of 48Ca in the TGV experiment

    International Nuclear Information System (INIS)

    The low-background, high-sensitivity Ge multi-detector spectrometer TVG was used to study the double-beta decay of 48Ca. Additional suppression of the registered background was achieved with a neutron shielding and a method of distinguishing β-particles from γ-rays by detector pulse rise time. The estimates T1/2ββ2ν = (4.2 ±2.4) x 1019 yr and T1/2ββ0ν > 1.5 x 1021 yr (90% C.L.) for the double-beta decay of 48Ca were obtained

  12. Impact of tensor force on \\beta-decay of magic and semi-magic nuclei

    OpenAIRE

    Minato, F.; Bai, C.L.

    2013-01-01

    Effect of the tensor force on $\\beta$?-decay is studied in the framework of the proton-neutron random-phase-approximation (RPA) with the Skyrme force. The investigation is performed for even-even semi-magic and magic nuclei, $^{34}$Si, $^{68}$, $^{78}$Ni and $^{132}$Sn. The tensor correlation induces strong impact on low-lying Gamow-Teller state. In particular, it improves the ?$\\beta$-decay half-lives. $Q$ and $ft$ values are also investigated and compared with experimental data.

  13. New limit on the neutrinoless double beta decay of 100Mo

    International Nuclear Information System (INIS)

    A search for the neutrinoless double beta decay of 100Mo was conducted using thin Mo films and solid state Si detectors. The experiment has collected 3500 hours of data operating underground in a deep silver mine (3290 M.W.E.). Only one event was found to be consistent with neutrinoless double beta decay. Using this one event, a limit of ≥ 1 x 1022 years (1 σ) is set on the 100Mo half-life. This is approximately five times larger than the best previous 100Mo limit

  14. Simulation studies for Tin Bolometer Array for Neutrinoless Double Beta Decay

    CERN Document Server

    Singh, V; Mathimalar, S; Nanal, V; Pillay, R G

    2014-01-01

    It is important to identify and reduce the gamma radiation which can be a significant source of background for any double beta decay experiment. The TIN.TIN detector array, which is under development for the search of Neutrinoless Double Beta Decay in $^{124}$Sn, has the potential to utilize the hit multiplicity information to discriminate the gamma background from the events of interest. Monte Carlo simulations for optimizing the design of a Tin detector module has been performed by varying element sizes with an emphasis on the gamma background reduction capabilities of the detector array.

  15. Evolution of the nuclear structure approaching $^{78}$Ni: $\\beta$ decay of $^{74-78}$Cu

    CERN Document Server

    Van Roosbroeck, J; De Maesschalck, A; De Witte, H; Fedorov, D; Fedosseev, V; Franchoo, S; Fynbo, H O U; Georg, U; Górska, M; Heyde, Kris L G; Huyse, M; Jonsson, O; Köster, U; Kruglov, K; Mishin, V I; Müller, W F; Pauwels, D; Smirnova, N A; Thomas, J C; Van Duppen, P; Van de Vel, K; Weissman, L

    2005-01-01

    A beta -decay study of the even mass /sup 74,76,78/Cu isotopes toward levels in /sup 74,76,78/Zn was performed at the ISOLDE mass separator. The copper isotopes were produced in proton- or neutron- induced fission reactions on /sup 238/U, laser ionized, mass separated, and sent to a beta - gamma detection system. Half-lives, decay schemes, and possible spin configurations were obtained for the copper isotopes. The results are compared with calculations using schematic forces as well as large-scale shell-model calculations with realistic forces.

  16. Systematic Law for Half-lives of Double $\\beta$-decay with Two Neutrinos

    CERN Document Server

    Ren, Yuejiao

    2014-01-01

    Nuclear double $\\beta$-decay with two neutrinos is a rare and important process for natural radioactivity of unstable nuclei. The experimental data of nuclear double $\\beta^{-}$-decay with two neutrinos are analyzed and a systematic law to calculate the half-lives of this rare process is proposed. It is the first analytical and simple formula for double $\\beta$-decay half-lives where the leading effect from both the Coulomb potential and nuclear structure is included. The systematic law shows that the logarithms of the half-lives are inversely proportional to the decay energies for the ground state transitions between parent nuclei and daughter nuclei. The calculated half-lives are in agreement with the experimental data of all known eleven nuclei with an average factor of 3.06. The half-lives of other possible double $\\beta$-decay candidates with two neutrinos are predicted and these can be useful for future experiments. The law, without introducing any extra adjustment, is also generalized to the calculatio...

  17. Design of a self-triggered liquid xenon drift chamber for double-beta decay experiments

    International Nuclear Information System (INIS)

    Nuclear double-beta decay is one of the rarest processes in nature with the half life of 1019 - 1024 years. Such process takes place only when a nucleus cannot undergo ordinary beta decay due to energy conservation, or the very strong suppression of energetically allowed transition exists. This process proceeds through the channels of standard second order weak decay (two neutrinos double-beta decay) and lepton number nonconserving, neutrinoless double-beta decay. An isotope of 136Xe possesses attractive properties for the studies on the nuclei subjected to nutrinoless mode. Gaseous or liquid xenon is an excellent working medium for drift chambers, and it can act as both source and detector providing so called active source technique of experiment. In order to search for the neutrinoless mode of 136Xe, the liquid xenon drift chamber was designed, which is composed of three electrodes and four photomultipliers. This drift chamber is described. Th gas handling and vacuum system consisting of a xenon gas purifier, a high vacuum pumping facility and gas storage reservoirs is explained. Event identification, charge division method, the estimation of signal rate and the present state of this study are reported. (K.I.)

  18. Effects of Beta-Decays of Excited-State Nuclei on the Astrophysical r-Process

    CERN Document Server

    Famiano, M A; Kajino, T; Otsuki, K; Terasawa, M; Mathews, G J

    2008-01-01

    A rudimentary calculation is employed to evaluate the possible effects of beta- decays of excited-state nuclei on the astrophysical r-process. Single-particle levels calculated with the FRDM are adapted to the calculation of beta-decay rates of these excited-state nuclei. Quantum numbers are determined based on proximity to Nilson model levels. The resulting rates are used in an r-process network calculation in which a supernova hot-bubble model is coupled to an extensive network calculation including all nuclei between the valley of stability and the neutron drip line and with masses A<284. Beta-decay rates are included as functional forms of the environmental temperature. While the decay rate model used is simple and phenomenological, it is consistent across all 3700 nuclei involved in the r-process network calculation. This represents an approximate first estimate to gauge the possible effects of excited-state beta-decays on r-process freeze-out abundances.

  19. New Technique for Barium Daughter Ion Identification in a Liquid Xe-136 Double Beta Decay Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Fairbank, William [Colorado State Univ., Fort Collins, CO (United States)

    2016-06-08

    This work addresses long-standing issues of fundamental interest in elementary particle physics. The most important outcome of this work is a new limit on neutrinoless double beta decay. This is an extremely rare and long sought after type of radioactive decay. If discovered, it would require changes in the standard model of the elementary constituents of matter, and would prove that neutrinos and antineutrinos are the same, a revolutionary concept in particle physics. Neutrinos are major components of the matter in the universe that are so small and so weakly interacting with other matter that their masses have not yet been discovered. A discovery of neutrinoless double beta decay could help determine the neutrino masses. An important outcome of the work on this project was the Colorado State University role in operating the EXO-200 neutrinoless double beta decay experiment and in analysis of the data from this experiment. One type of double beta decay of the isotope 136Xe, the two-neutrino variety, was discovered in this work. Although the other type of double beta decay, the neutrinoless variety, was not yet discovered in this work, a world’s best sensitivity of 1.9x1025 year half-life was obtained. This result rules out a previous claim of a positive result in a different isotope. This work also establishes that the masses of the neutrinos, are less than one millionth of that of electrons. A unique EXO-200 analysis, in which the CSU group had a leading role, has established for the first time ever in a liquid noble gas the fraction of daughter atoms from alpha and beta decay that are ionized. This result has important impact on other pending studies, including nucleon decay and barium tagging. Novel additional discoveries include multiphoton ionization of liquid xenon with UV pulsed lasers, which may find application in calibration of future noble liquid detectors, and studies of association and dissociation reactions of Ba+ ions in gaseous xenon. Through

  20. Angular analysis and branching fraction measurement of the decay $B^0 \\to K^{*0} \\mu^+\\mu^-$

    CERN Document Server

    Chatrchyan, Serguei; Sirunyan, Albert M; Tumasyan, Armen; Adam, Wolfgang; Bergauer, Thomas; Dragicevic, Marko; Erö, Janos; Fabjan, Christian; Friedl, Markus; Fruehwirth, Rudolf; Ghete, Vasile Mihai; Hörmann, Natascha; Hrubec, Josef; Jeitler, Manfred; Kiesenhofer, Wolfgang; Knünz, Valentin; Krammer, Manfred; Krätschmer, Ilse; Liko, Dietrich; Mikulec, Ivan; Rabady, Dinyar; Rahbaran, Babak; Rohringer, Christine; Rohringer, Herbert; Schöfbeck, Robert; Strauss, Josef; Taurok, Anton; Treberer-Treberspurg, Wolfgang; Waltenberger, Wolfgang; Wulz, Claudia-Elisabeth; Mossolov, Vladimir; Shumeiko, Nikolai; Suarez Gonzalez, Juan; Alderweireldt, Sara; Bansal, Monika; Bansal, Sunil; Cornelis, Tom; De Wolf, Eddi A; Janssen, Xavier; Knutsson, Albert; Luyckx, Sten; Mucibello, Luca; Ochesanu, Silvia; Roland, Benoit; Rougny, Romain; Staykova, Zlatka; Van Haevermaet, Hans; Van Mechelen, Pierre; Van Remortel, Nick; Van Spilbeeck, Alex; Blekman, Freya; Blyweert, Stijn; D'Hondt, Jorgen; Kalogeropoulos, Alexis; Keaveney, James; Maes, Michael; Olbrechts, Annik; Tavernier, Stefaan; Van Doninck, Walter; Van Mulders, Petra; Van Onsem, Gerrit Patrick; Villella, Ilaria; Caillol, Cécile; Clerbaux, Barbara; De Lentdecker, Gilles; Favart, Laurent; Gay, Arnaud; Hreus, Tomas; Léonard, Alexandre; Marage, Pierre Edouard; Mohammadi, Abdollah; Perniè, Luca; Reis, Thomas; Seva, Tomislav; Thomas, Laurent; Vander Velde, Catherine; Vanlaer, Pascal; Wang, Jian; Adler, Volker; Beernaert, Kelly; Benucci, Leonardo; Cimmino, Anna; Costantini, Silvia; Dildick, Sven; Garcia, Guillaume; Klein, Benjamin; Lellouch, Jérémie; Marinov, Andrey; Mccartin, Joseph; Ocampo Rios, Alberto Andres; Ryckbosch, Dirk; Sigamani, Michael; Strobbe, Nadja; Thyssen, Filip; Tytgat, Michael; Walsh, Sinead; Yazgan, Efe; Zaganidis, Nicolas; Basegmez, Suzan; Beluffi, Camille; Bruno, Giacomo; Castello, Roberto; Caudron, Adrien; Ceard, Ludivine; Da Silveira, Gustavo Gil; Delaere, Christophe; Du Pree, Tristan; Favart, Denis; Forthomme, Laurent; Giammanco, Andrea; Hollar, Jonathan; Jez, Pavel; Lemaitre, Vincent; Liao, Junhui; Militaru, Otilia; Nuttens, Claude; Pagano, Davide; Pin, Arnaud; Piotrzkowski, Krzysztof; Popov, Andrey; Selvaggi, Michele; Vizan Garcia, Jesus Manuel; Beliy, Nikita; Caebergs, Thierry; Daubie, Evelyne; Hammad, Gregory Habib; Alves, Gilvan; Correa Martins Junior, Marcos; Martins, Thiago; Pol, Maria Elena; Henrique Gomes E Souza, Moacyr; Aldá Júnior, Walter Luiz; Carvalho, Wagner; Chinellato, Jose; Custódio, Analu; Da Costa, Eliza Melo; De Jesus Damiao, Dilson; De Oliveira Martins, Carley; Fonseca De Souza, Sandro; Malbouisson, Helena; Malek, Magdalena; Matos Figueiredo, Diego; Mundim, Luiz; Nogima, Helio; Prado Da Silva, Wanda Lucia; Santoro, Alberto; Sznajder, Andre; Tonelli Manganote, Edmilson José; Vilela Pereira, Antonio; Bernardes, Cesar Augusto; De Almeida Dias, Flavia; Tomei, Thiago; De Moraes Gregores, Eduardo; Lagana, Caio; Mercadante, Pedro G; Novaes, Sergio F; Padula, Sandra; Genchev, Vladimir; Iaydjiev, Plamen; Piperov, Stefan; Rodozov, Mircho; Sultanov, Georgi; Vutova, Mariana; Dimitrov, Anton; Hadjiiska, Roumyana; Kozhuharov, Venelin; Litov, Leander; Pavlov, Borislav; Petkov, Peicho; Bian, Jian-Guo; Chen, Guo-Ming; Chen, He-Sheng; Jiang, Chun-Hua; Liang, Dong; Liang, Song; Meng, Xiangwei; Tao, Junquan; Wang, Xianyou; Wang, Zheng; Xiao, Hong; Asawatangtrakuldee, Chayanit; Ban, Yong; Guo, Yifei; Li, Wenbo; Liu, Shuai; Mao, Yajun; Qian, Si-Jin; Teng, Haiyun; Wang, Dayong; Zhang, Linlin; Zou, Wei; Avila, Carlos; Carrillo Montoya, Camilo Andres; Chaparro Sierra, Luisa Fernanda; Gomez, Juan Pablo; Gomez Moreno, Bernardo; Sanabria, Juan Carlos; Godinovic, Nikola; Lelas, Damir; Plestina, Roko; Polic, Dunja; Puljak, Ivica; Antunovic, Zeljko; Kovac, Marko; Brigljevic, Vuko; Kadija, Kreso; Luetic, Jelena; Mekterovic, Darko; Morovic, Srecko; Tikvica, Lucija; Attikis, Alexandros; Mavromanolakis, Georgios; Mousa, Jehad; Nicolaou, Charalambos; Ptochos, Fotios; Razis, Panos A; Finger, Miroslav; Finger Jr, Michael; Abdelalim, Ahmed Ali; Assran, Yasser; Elgammal, Sherif; Ellithi Kamel, Ali; Mahmoud, Mohammed; Radi, Amr; Kadastik, Mario; Müntel, Mait; Murumaa, Marion; Raidal, Martti; Rebane, Liis; Tiko, Andres; Eerola, Paula; Fedi, Giacomo; Voutilainen, Mikko; Härkönen, Jaakko; Karimäki, Veikko; Kinnunen, Ritva; Kortelainen, Matti J; Lampén, Tapio; Lassila-Perini, Kati; Lehti, Sami; Lindén, Tomas; Luukka, Panja-Riina; Mäenpää, Teppo; Peltola, Timo; Tuominen, Eija; Tuominiemi, Jorma; Tuovinen, Esa; Wendland, Lauri; Tuuva, Tuure; Besancon, Marc; Couderc, Fabrice; Dejardin, Marc; Denegri, Daniel; Fabbro, Bernard; Faure, Jean-Louis; Ferri, Federico; Ganjour, Serguei; Givernaud, Alain; Gras, Philippe; Hamel de Monchenault, Gautier; Jarry, Patrick; Locci, Elizabeth; Malcles, Julie; Millischer, Laurent; Nayak, Aruna; Rander, John; Rosowsky, André; Titov, Maksym; Baffioni, Stephanie; Beaudette, Florian; Benhabib, Lamia; Bluj, Michal; Busson, Philippe; Charlot, Claude; Daci, Nadir; Dahms, Torsten; Dalchenko, Mykhailo; Dobrzynski, Ludwik; Florent, Alice; Granier de Cassagnac, Raphael; Haguenauer, Maurice; Miné, Philippe; Mironov, Camelia; Naranjo, Ivo Nicolas; Nguyen, Matthew; Ochando, Christophe; Paganini, Pascal; Sabes, David; Salerno, Roberto; Sirois, Yves; Veelken, Christian; Zabi, Alexandre; Agram, Jean-Laurent; Andrea, Jeremy; Bloch, Daniel; Brom, Jean-Marie; Chabert, Eric Christian; Collard, Caroline; Conte, Eric; Drouhin, Frédéric; Fontaine, Jean-Charles; Gelé, Denis; Goerlach, Ulrich; Goetzmann, Christophe; Juillot, Pierre; Le Bihan, Anne-Catherine; Van Hove, Pierre; Gadrat, Sébastien; Beauceron, Stephanie; Beaupere, Nicolas; Boudoul, Gaelle; Brochet, Sébastien; Chasserat, Julien; Chierici, Roberto; Contardo, Didier; Depasse, Pierre; El Mamouni, Houmani; Fay, Jean; Gascon, Susan; Gouzevitch, Maxime; Ille, Bernard; Kurca, Tibor; Lethuillier, Morgan; Mirabito, Laurent; Perries, Stephane; Sgandurra, Louis; Sordini, Viola; Vander Donckt, Muriel; Verdier, Patrice; Viret, Sébastien; Tsamalaidze, Zviad; Autermann, Christian; Beranek, Sarah; Calpas, Betty; Edelhoff, Matthias; Feld, Lutz; Heracleous, Natalie; Hindrichs, Otto; Klein, Katja; Ostapchuk, Andrey; Perieanu, Adrian; Raupach, Frank; Sammet, Jan; Schael, Stefan; Sprenger, Daniel; Weber, Hendrik; Wittmer, Bruno; Zhukov, Valery; Ata, Metin; Caudron, Julien; Dietz-Laursonn, Erik; Duchardt, Deborah; Erdmann, Martin; Fischer, Robert; Güth, Andreas; Hebbeker, Thomas; Heidemann, Carsten; Hoepfner, Kerstin; Klingebiel, Dennis; Knutzen, Simon; Kreuzer, Peter; Merschmeyer, Markus; Meyer, Arnd; Olschewski, Mark; Padeken, Klaas; Papacz, Paul; Pieta, Holger; Reithler, Hans; Schmitz, Stefan Antonius; Sonnenschein, Lars; Steggemann, Jan; Teyssier, Daniel; Thüer, Sebastian; Weber, Martin; Cherepanov, Vladimir; Erdogan, Yusuf; Flügge, Günter; Geenen, Heiko; Geisler, Matthias; Haj Ahmad, Wael; Hoehle, Felix; Kargoll, Bastian; Kress, Thomas; Kuessel, Yvonne; Lingemann, Joschka; Nowack, Andreas; Nugent, Ian Michael; Perchalla, Lars; Pooth, Oliver; Stahl, Achim; Asin, Ivan; Bartosik, Nazar; Behr, Joerg; Behrenhoff, Wolf; Behrens, Ulf; Bell, Alan James; Bergholz, Matthias; Bethani, Agni; Borras, Kerstin; Burgmeier, Armin; Cakir, Altan; Calligaris, Luigi; Campbell, Alan; Choudhury, Somnath; Costanza, Francesco; Diez Pardos, Carmen; Dooling, Samantha; Dorland, Tyler; Eckerlin, Guenter; Eckstein, Doris; Flucke, Gero; Geiser, Achim; Glushkov, Ivan; Grebenyuk, Anastasia; Gunnellini, Paolo; Habib, Shiraz; Hauk, Johannes; Hellwig, Gregor; Horton, Dean; Jung, Hannes; Kasemann, Matthias; Katsas, Panagiotis; Kleinwort, Claus; Kluge, Hannelies; Krämer, Mira; Krücker, Dirk; Kuznetsova, Ekaterina; Lange, Wolfgang; Leonard, Jessica; Lipka, Katerina; Lohmann, Wolfgang; Lutz, Benjamin; Mankel, Rainer; Marfin, Ihar; Melzer-Pellmann, Isabell-Alissandra; Meyer, Andreas Bernhard; Mnich, Joachim; Mussgiller, Andreas; Naumann-Emme, Sebastian; Novgorodova, Olga; Nowak, Friederike; Olzem, Jan; Perrey, Hanno; Petrukhin, Alexey; Pitzl, Daniel; Placakyte, Ringaile; Raspereza, Alexei; Ribeiro Cipriano, Pedro M; Riedl, Caroline; Ron, Elias; Sahin, Mehmet Özgür; Salfeld-Nebgen, Jakob; Schmidt, Ringo; Schoerner-Sadenius, Thomas; Sen, Niladri; Stein, Matthias; Walsh, Roberval; Wissing, Christoph; Aldaya Martin, Maria; Blobel, Volker; Enderle, Holger; Erfle, Joachim; Garutti, Erika; Gebbert, Ulla; Görner, Martin; Gosselink, Martijn; Haller, Johannes; Heine, Kristin; Höing, Rebekka Sophie; Kaussen, Gordon; Kirschenmann, Henning; Klanner, Robert; Kogler, Roman; Lange, Jörn; Marchesini, Ivan; Peiffer, Thomas; Pietsch, Niklas; Rathjens, Denis; Sander, Christian; Schettler, Hannes; Schleper, Peter; Schlieckau, Eike; Schmidt, Alexander; Schröder, Matthias; Schum, Torben; Seidel, Markus; Sibille, Jennifer; Sola, Valentina; Stadie, Hartmut; Steinbrück, Georg; Thomsen, Jan; Troendle, Daniel; Usai, Emanuele; Vanelderen, Lukas; Barth, Christian; Baus, Colin; Berger, Joram; Böser, Christian; Butz, Erik; Chwalek, Thorsten; De Boer, Wim; Descroix, Alexis; Dierlamm, Alexander; Feindt, Michael; Guthoff, Moritz; Hartmann, Frank; Hauth, Thomas; Held, Hauke; Hoffmann, Karl-Heinz; Husemann, Ulrich; Katkov, Igor; Komaragiri, Jyothsna Rani; Kornmayer, Andreas; Lobelle Pardo, Patricia; Martschei, Daniel; Müller, Thomas; Niegel, Martin; Nürnberg, Andreas; Oberst, Oliver; Ott, Jochen; Quast, Gunter; Rabbertz, Klaus; Ratnikov, Fedor; Röcker, Steffen; Schilling, Frank-Peter; Schott, Gregory; Simonis, Hans-Jürgen; Stober, Fred-Markus Helmut; Ulrich, Ralf; Wagner-Kuhr, Jeannine; Wayand, Stefan; Weiler, Thomas; Zeise, Manuel; Anagnostou, Georgios; Daskalakis, Georgios; Geralis, Theodoros; Kesisoglou, Stilianos; Kyriakis, Aristotelis; Loukas, Demetrios; Markou, Athanasios; Markou, Christos; Ntomari, Eleni; Topsis-giotis, Iasonas; Gouskos, Loukas; Panagiotou, Apostolos; Saoulidou, Niki; Stiliaris, Efstathios; Aslanoglou, Xenofon; Evangelou, Ioannis; Flouris, Giannis; Foudas, Costas; Kokkas, Panagiotis; Manthos, Nikolaos; Papadopoulos, Ioannis; Paradas, Evangelos; Bencze, Gyorgy; Hajdu, Csaba; Hidas, Pàl; Horvath, Dezso; Sikler, Ferenc; Veszpremi, Viktor; Vesztergombi, Gyorgy; Zsigmond, Anna Julia; Beni, Noemi; Czellar, Sandor; Molnar, Jozsef; Palinkas, Jozsef; Szillasi, Zoltan; Karancsi, János; Raics, Peter; Trocsanyi, Zoltan Laszlo; Ujvari, Balazs; Swain, Sanjay Kumar; Beri, Suman Bala; Bhatnagar, Vipin; Dhingra, Nitish; Gupta, Ruchi; Kaur, Manjit; Mehta, Manuk Zubin; Mittal, Monika; Nishu, Nishu; Sharma, Archana; Singh, Jasbir; Kumar, Ashok; Kumar, Arun; Ahuja, Sudha; Bhardwaj, Ashutosh; Choudhary, Brajesh C; Malhotra, Shivali; Naimuddin, Md; Ranjan, Kirti; Saxena, Pooja; Sharma, Varun; Shivpuri, Ram Krishen; Banerjee, Sunanda; Bhattacharya, Satyaki; Chatterjee, Kalyanmoy; Dutta, Suchandra; Gomber, Bhawna; Jain, Sandhya; Jain, Shilpi; Khurana, Raman; Modak, Atanu; Mukherjee, Swagata; Roy, Debarati; Sarkar, Subir; Sharan, Manoj; Singh, Anil; Abdulsalam, Abdulla; Dutta, Dipanwita; Kailas, Swaminathan; Kumar, Vineet; Mohanty, Ajit Kumar; Pant, Lalit Mohan; Shukla, Prashant; Topkar, Anita; Aziz, Tariq; Chatterjee, Rajdeep Mohan; Ganguly, Sanmay; Ghosh, Saranya; Guchait, Monoranjan; Gurtu, Atul; Kole, Gouranga; Kumar, Sanjeev; Maity, Manas; Majumder, Gobinda; Mazumdar, Kajari; Mohanty, Gagan Bihari; Parida, Bibhuti; Sudhakar, Katta; Wickramage, Nadeesha; Banerjee, Sudeshna; Dugad, Shashikant; Arfaei, Hessamaddin; Bakhshiansohi, Hamed; Etesami, Seyed Mohsen; Fahim, Ali; Jafari, Abideh; Khakzad, Mohsen; Mohammadi Najafabadi, Mojtaba; Paktinat Mehdiabadi, Saeid; Safarzadeh, Batool; Zeinali, Maryam; Grunewald, Martin; Abbrescia, Marcello; Barbone, Lucia; Calabria, Cesare; Chhibra, Simranjit Singh; Colaleo, Anna; Creanza, Donato; De Filippis, Nicola; De Palma, Mauro; Fiore, Luigi; Iaselli, Giuseppe; Maggi, Giorgio; Maggi, Marcello; Marangelli, Bartolomeo; My, Salvatore; Nuzzo, Salvatore; Pacifico, Nicola; Pompili, Alexis; Pugliese, Gabriella; Selvaggi, Giovanna; Silvestris, Lucia; Singh, Gurpreet; Venditti, Rosamaria; Verwilligen, Piet; Zito, Giuseppe; Abbiendi, Giovanni; Benvenuti, Alberto; Bonacorsi, Daniele; Braibant-Giacomelli, Sylvie; Brigliadori, Luca; Campanini, Renato; Capiluppi, Paolo; Castro, Andrea; Cavallo, Francesca Romana; Codispoti, Giuseppe; Cuffiani, Marco; Dallavalle, Gaetano-Marco; Fabbri, Fabrizio; Fanfani, Alessandra; Fasanella, Daniele; Giacomelli, Paolo; Grandi, Claudio; Guiducci, Luigi; Marcellini, Stefano; Masetti, Gianni; Meneghelli, Marco; Montanari, Alessandro; Navarria, Francesco; Odorici, Fabrizio; Perrotta, Andrea; Primavera, Federica; Rossi, Antonio; Rovelli, Tiziano; Siroli, Gian Piero; Tosi, Nicolò; Travaglini, Riccardo; Albergo, Sebastiano; Chiorboli, Massimiliano; Costa, Salvatore; Giordano, Ferdinando; Potenza, Renato; Tricomi, Alessia; Tuve, Cristina; Barbagli, Giuseppe; Ciulli, Vitaliano; Civinini, Carlo; D'Alessandro, Raffaello; Focardi, Ettore; Frosali, Simone; Gallo, Elisabetta; Gonzi, Sandro; Gori, Valentina; Lenzi, Piergiulio; Meschini, Marco; Paoletti, Simone; Sguazzoni, Giacomo; Tropiano, Antonio; Benussi, Luigi; Bianco, Stefano; Fabbri, Franco; Piccolo, Davide; Fabbricatore, Pasquale; Ferro, Fabrizio; Lo Vetere, Maurizio; Musenich, Riccardo; Tosi, Silvano; Benaglia, Andrea; Dinardo, Mauro Emanuele; Fiorendi, Sara; Gennai, Simone; Ghezzi, Alessio; Govoni, Pietro; Lucchini, Marco Toliman; Malvezzi, Sandra; Manzoni, Riccardo Andrea; Martelli, Arabella; Menasce, Dario; Moroni, Luigi; Paganoni, Marco; Pedrini, Daniele; Ragazzi, Stefano; Redaelli, Nicola; Tabarelli de Fatis, Tommaso; Buontempo, Salvatore; Cavallo, Nicola; De Cosa, Annapaola; Fabozzi, Francesco; Iorio, Alberto Orso Maria; Lista, Luca; Meola, Sabino; Merola, Mario; Paolucci, Pierluigi; Azzi, Patrizia; Bacchetta, Nicola; Bellato, Marco; Bisello, Dario; Branca, Antonio; Carlin, Roberto; Checchia, Paolo; Dorigo, Tommaso; Dosselli, Umberto; Galanti, Mario; Gasparini, Fabrizio; Gasparini, Ugo; Giubilato, Piero; Gozzelino, Andrea; Kanishchev, Konstantin; Lacaprara, Stefano; Lazzizzera, Ignazio; Margoni, Martino; Meneguzzo, Anna Teresa; Passaseo, Marina; Pazzini, Jacopo; Pegoraro, Matteo; Pozzobon, Nicola; Ronchese, Paolo; Simonetto, Franco; Torassa, Ezio; Tosi, Mia; Ventura, Sandro; Zotto, Pierluigi; Zucchetta, Alberto; Zumerle, Gianni; Gabusi, Michele; Ratti, Sergio P; Riccardi, Cristina; Vitulo, Paolo; Biasini, Maurizio; Bilei, Gian Mario; Fanò, Livio; Lariccia, Paolo; Mantovani, Giancarlo; Menichelli, Mauro; Nappi, Aniello; Romeo, Francesco; Saha, Anirban; Santocchia, Attilio; Spiezia, Aniello; Androsov, Konstantin; Azzurri, Paolo; Bagliesi, Giuseppe; Boccali, Tommaso; Broccolo, Giuseppe; Castaldi, Rino; Ciocci, Maria Agnese; D'Agnolo, Raffaele Tito; Dell'Orso, Roberto; Fiori, Francesco; Foà, Lorenzo; Giassi, Alessandro; Grippo, Maria Teresa; Kraan, Aafke; Ligabue, Franco; Lomtadze, Teimuraz; Martini, Luca; Messineo, Alberto; Moon, Chang-Seong; Palla, Fabrizio; Rizzi, Andrea; Savoy-Navarro, Aurore; Serban, Alin Titus; Spagnolo, Paolo; Squillacioti, Paola; Tenchini, Roberto; Tonelli, Guido; Venturi, Andrea; Verdini, Piero Giorgio; Vernieri, Caterina; Barone, Luciano; Cavallari, Francesca; Del Re, Daniele; Diemoz, Marcella; Grassi, Marco; Longo, Egidio; Margaroli, Fabrizio; Meridiani, Paolo; Micheli, Francesco; Nourbakhsh, Shervin; Organtini, Giovanni; Paramatti, Riccardo; Rahatlou, Shahram; Rovelli, Chiara; Soffi, Livia; Amapane, Nicola; Arcidiacono, Roberta; Argiro, Stefano; Arneodo, Michele; Bellan, Riccardo; Biino, Cristina; Cartiglia, Nicolo; Casasso, Stefano; Costa, Marco; Degano, Alessandro; Demaria, Natale; Mariotti, Chiara; Maselli, Silvia; Migliore, Ernesto; Monaco, Vincenzo; Musich, Marco; Obertino, Maria Margherita; Pastrone, Nadia; Pelliccioni, Mario; Potenza, Alberto; Romero, Alessandra; Ruspa, Marta; Sacchi, Roberto; Solano, Ada; Staiano, Amedeo; Tamponi, Umberto; Belforte, Stefano; Candelise, Vieri; Casarsa, Massimo; Cossutti, Fabio; Della Ricca, Giuseppe; Gobbo, Benigno; La Licata, Chiara; Marone, Matteo; Montanino, Damiana; Penzo, Aldo; Schizzi, Andrea; Zanetti, Anna; Chang, Sunghyun; Kim, Tae Yeon; Nam, Soon-Kwon; Kim, Dong Hee; Kim, Gui Nyun; Kim, Ji Eun; Kong, Dae Jung; Lee, Sangeun; Oh, Young Do; Park, Hyangkyu; Son, Dong-Chul; Kim, Jae Yool; Kim, Zero Jaeho; Song, Sanghyeon; Choi, Suyong; Gyun, Dooyeon; Hong, Byung-Sik; Jo, Mihee; Kim, Hyunchul; Kim, Tae Jeong; Lee, Kyong Sei; Park, Sung Keun; Roh, Youn; Choi, Minkyoo; Kim, Ji Hyun; Park, Chawon; Park, Inkyu; Park, Sangnam; Ryu, Geonmo; Choi, Young-Il; Choi, Young Kyu; Goh, Junghwan; Kim, Min Suk; Kwon, Eunhyang; Lee, Byounghoon; Lee, Jongseok; Lee, Sungeun; Seo, Hyunkwan; Yu, Intae; Grigelionis, Ignas; Juodagalvis, Andrius; Castilla-Valdez, Heriberto; De La Cruz-Burelo, Eduard; Heredia-de La Cruz, Ivan; Lopez-Fernandez, Ricardo; Martínez-Ortega, Jorge; Sánchez Hernández, Alberto; Villasenor-Cendejas, Luis Manuel; Carrillo Moreno, Salvador; Vazquez Valencia, Fabiola; Salazar Ibarguen, Humberto Antonio; Casimiro Linares, Edgar; Morelos Pineda, Antonio; Reyes-Santos, Marco A; Krofcheck, David; Butler, Philip H; Doesburg, Robert; Reucroft, Steve; Silverwood, Hamish; Ahmad, Muhammad; Asghar, Muhammad Irfan; Butt, Jamila; Hoorani, Hafeez R; Khalid, Shoaib; Khan, Wajid Ali; Khurshid, Taimoor; Qazi, Shamona; Shah, Mehar Ali; Shoaib, Muhammad; Bialkowska, Helena; Boimska, Bożena; Frueboes, Tomasz; Górski, Maciej; Kazana, Malgorzata; Nawrocki, Krzysztof; Romanowska-Rybinska, Katarzyna; Szleper, Michal; Wrochna, Grzegorz; Zalewski, Piotr; Brona, Grzegorz; Bunkowski, Karol; Cwiok, Mikolaj; Dominik, Wojciech; Doroba, Krzysztof; Kalinowski, Artur; Konecki, Marcin; Krolikowski, Jan; Misiura, Maciej; Wolszczak, Weronika; Almeida, Nuno; Bargassa, Pedrame; Beirão Da Cruz E Silva, Cristóvão; Faccioli, Pietro; Ferreira Parracho, Pedro Guilherme; Gallinaro, Michele; Nguyen, Federico; Rodrigues Antunes, Joao; Seixas, Joao; Varela, Joao; Vischia, Pietro; Afanasiev, Serguei; Bunin, Pavel; Gavrilenko, Mikhail; Golutvin, Igor; Gorbunov, Ilya; Kamenev, Alexey; Karjavin, Vladimir; Konoplyanikov, Viktor; Lanev, Alexander; Malakhov, Alexander; Matveev, Viktor; Moisenz, Petr; Palichik, Vladimir; Perelygin, Victor; Shmatov, Sergey; Skatchkov, Nikolai; Smirnov, Vitaly; Zarubin, Anatoli; Evstyukhin, Sergey; Golovtsov, Victor; Ivanov, Yury; Kim, Victor; Levchenko, Petr; Murzin, Victor; Oreshkin, Vadim; Smirnov, Igor; Sulimov, Valentin; Uvarov, Lev; Vavilov, Sergey; Vorobyev, Alexey; Vorobyev, Andrey; Andreev, Yuri; Dermenev, Alexander; Gninenko, Sergei; Golubev, Nikolai; Kirsanov, Mikhail; Krasnikov, Nikolai; Pashenkov, Anatoli; Tlisov, Danila; Toropin, Alexander; Epshteyn, Vladimir; Erofeeva, Maria; Gavrilov, Vladimir; Lychkovskaya, Natalia; Popov, Vladimir; Safronov, Grigory; Semenov, Sergey; Spiridonov, Alexander; Stolin, Viatcheslav; Vlasov, Evgueni; Zhokin, Alexander; Andreev, Vladimir; Azarkin, Maksim; Dremin, Igor; Kirakosyan, Martin; Leonidov, Andrey; Mesyats, Gennady; Rusakov, Sergey V; Vinogradov, Alexey; Belyaev, Andrey; Boos, Edouard; Dubinin, Mikhail; Dudko, Lev; Ershov, Alexander; Gribushin, Andrey; Klyukhin, Vyacheslav; Kodolova, Olga; Lokhtin, Igor; Markina, Anastasia; Obraztsov, Stepan; Petrushanko, Sergey; Savrin, Viktor; Snigirev, Alexander; Azhgirey, Igor; Bayshev, Igor; Bitioukov, Sergei; Kachanov, Vassili; Kalinin, Alexey; Konstantinov, Dmitri; Krychkine, Victor; Petrov, Vladimir; Ryutin, Roman; Sobol, Andrei; Tourtchanovitch, Leonid; Troshin, Sergey; Tyurin, Nikolay; Uzunian, Andrey; Volkov, Alexey; Adzic, Petar; Djordjevic, Milos; Ekmedzic, Marko; Krpic, Dragomir; Milosevic, Jovan; Aguilar-Benitez, Manuel; Alcaraz Maestre, Juan; Battilana, Carlo; Calvo, Enrique; Cerrada, Marcos; Chamizo Llatas, Maria; Colino, Nicanor; De La Cruz, Begona; Delgado Peris, Antonio; Domínguez Vázquez, Daniel; Fernandez Bedoya, Cristina; Fernández Ramos, Juan Pablo; Ferrando, Antonio; Flix, Jose; Fouz, Maria Cruz; Garcia-Abia, Pablo; Gonzalez Lopez, Oscar; Goy Lopez, Silvia; Hernandez, Jose M; Josa, Maria Isabel; Merino, Gonzalo; Navarro De Martino, Eduardo; Puerta Pelayo, Jesus; Quintario Olmeda, Adrián; Redondo, Ignacio; Romero, Luciano; Santaolalla, Javier; Soares, Mara Senghi; Willmott, Carlos; Albajar, Carmen; de Trocóniz, Jorge F; Brun, Hugues; Cuevas, Javier; Fernandez Menendez, Javier; Folgueras, Santiago; Gonzalez Caballero, Isidro; Lloret Iglesias, Lara; Piedra Gomez, Jonatan; Brochero Cifuentes, Javier Andres; Cabrillo, Iban Jose; Calderon, Alicia; Chuang, Shan-Huei; Duarte Campderros, Jordi; Fernandez, Marcos; Gomez, Gervasio; Gonzalez Sanchez, Javier; Graziano, Alberto; Jorda, Clara; Lopez Virto, Amparo; Marco, Jesus; Marco, Rafael; Martinez Rivero, Celso; Matorras, Francisco; Munoz Sanchez, Francisca Javiela; Rodrigo, Teresa; Rodríguez-Marrero, Ana Yaiza; Ruiz-Jimeno, Alberto; Scodellaro, Luca; Vila, Ivan; Vilar Cortabitarte, Rocio; Abbaneo, Duccio; Auffray, Etiennette; Auzinger, Georg; Bachtis, Michail; Baillon, Paul; Ball, Austin; Barney, David; Bendavid, Joshua; Benitez, Jose F; Bernet, Colin; Bianchi, Giovanni; Bloch, Philippe; Bocci, Andrea; Bonato, Alessio; Bondu, Olivier; Botta, Cristina; Breuker, Horst; Camporesi, Tiziano; Cerminara, Gianluca; Christiansen, Tim; Coarasa Perez, Jose Antonio; Colafranceschi, Stefano; D'Alfonso, Mariarosaria; D'Enterria, David; Dabrowski, Anne; David Tinoco Mendes, Andre; De Guio, Federico; De Roeck, Albert; De Visscher, Simon; Di Guida, Salvatore; Dobson, Marc; Dupont-Sagorin, Niels; Elliott-Peisert, Anna; Eugster, Jürg; Funk, Wolfgang; Georgiou, Georgios; Giffels, Manuel; Gigi, Dominique; Gill, Karl; Giordano, Domenico; Girone, Maria; Giunta, Marina; Glege, Frank; Gomez-Reino Garrido, Robert; Gowdy, Stephen; Guida, Roberto; Hammer, Josef; Hansen, Magnus; Harris, Philip; Hartl, Christian; Hinzmann, Andreas; Innocente, Vincenzo; Janot, Patrick; Karavakis, Edward; Kousouris, Konstantinos; Krajczar, Krisztian; Lecoq, Paul; Lee, Yen-Jie; Lourenco, Carlos; Magini, Nicolo; Malgeri, Luca; Mannelli, Marcello; Masetti, Lorenzo; Meijers, Frans; Mersi, Stefano; Meschi, Emilio; Moser, Roland; Mulders, Martijn; Musella, Pasquale; Nesvold, Erik; Orsini, Luciano; Palencia Cortezon, Enrique; Perez, Emmanuelle; Perrozzi, Luca; Petrilli, Achille; Pfeiffer, Andreas; Pierini, Maurizio; Pimiä, Martti; Piparo, Danilo; Plagge, Michael; Quertenmont, Loic; Racz, Attila; Reece, William; Rolandi, Gigi; Rovere, Marco; Sakulin, Hannes; Santanastasio, Francesco; Schäfer, Christoph; Schwick, Christoph; Segoni, Ilaria; Sekmen, Sezen; Sharma, Archana; Siegrist, Patrice; Silva, Pedro; Simon, Michal; Sphicas, Paraskevas; Spiga, Daniele; Stoye, Markus; Tsirou, Andromachi; Veres, Gabor Istvan; Vlimant, Jean-Roch; Wöhri, Hermine Katharina; Worm, Steven; Zeuner, Wolfram Dietrich; Bertl, Willi; Deiters, Konrad; Erdmann, Wolfram; Gabathuler, Kurt; Horisberger, Roland; Ingram, Quentin; Kaestli, Hans-Christian; König, Stefan; Kotlinski, Danek; Langenegger, Urs; Renker, Dieter; Rohe, Tilman; Bachmair, Felix; Bäni, Lukas; Bianchini, Lorenzo; Bortignon, Pierluigi; Buchmann, Marco-Andrea; Casal, Bruno; Chanon, Nicolas; Deisher, Amanda; Dissertori, Günther; Dittmar, Michael; Donegà, Mauro; Dünser, Marc; Eller, Philipp; Freudenreich, Klaus; Grab, Christoph; Hits, Dmitry; Lecomte, Pierre; Lustermann, Werner; Mangano, Boris; Marini, Andrea Carlo; Martinez Ruiz del Arbol, Pablo; Meister, Daniel; Mohr, Niklas; Moortgat, Filip; Nägeli, Christoph; Nef, Pascal; Nessi-Tedaldi, Francesca; Pandolfi, Francesco; Pape, Luc; Pauss, Felicitas; Peruzzi, Marco; Ronga, Frederic Jean; Rossini, Marco; Sala, Leonardo; Sanchez, Ann - Karin; Starodumov, Andrei; Stieger, Benjamin; Takahashi, Maiko; Tauscher, Ludwig; Thea, Alessandro; Theofilatos, Konstantinos; Treille, Daniel; Urscheler, Christina; Wallny, Rainer; Weber, Hannsjoerg Artur; Amsler, Claude; Chiochia, Vincenzo; Favaro, Carlotta; Ivova Rikova, Mirena; Kilminster, Benjamin; Millan Mejias, Barbara; Robmann, Peter; Snoek, Hella; Taroni, Silvia; Verzetti, Mauro; Yang, Yong; Cardaci, Marco; Chen, Kuan-Hsin; Ferro, Cristina; Kuo, Chia-Ming; Li, Syue-Wei; Lin, Willis; Lu, Yun-Ju; Volpe, Roberta; Yu, Shin-Shan; Bartalini, Paolo; Chang, Paoti; Chang, You-Hao; 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Iles, Gregory; Jarvis, Martyn; Karapostoli, Georgia; Kenzie, Matthew; Lane, Rebecca; Lucas, Robyn; Lyons, Louis; Magnan, Anne-Marie; Marrouche, Jad; Mathias, Bryn; Nandi, Robin; Nash, Jordan; Nikitenko, Alexander; Pela, Joao; Pesaresi, Mark; Petridis, Konstantinos; Pioppi, Michele; Raymond, David Mark; Rogerson, Samuel; Rose, Andrew; Seez, Christopher; Sharp, Peter; Sparrow, Alex; Tapper, Alexander; Vazquez Acosta, Monica; Virdee, Tejinder; Wakefield, Stuart; Wardle, Nicholas; Whyntie, Tom; Chadwick, Matthew; Cole, Joanne; Hobson, Peter R; Khan, Akram; Kyberd, Paul; Leggat, Duncan; Leslie, Dawn; Martin, William; Reid, Ivan; Symonds, Philip; Teodorescu, Liliana; Turner, Mark; Dittmann, Jay; Hatakeyama, Kenichi; Kasmi, Azeddine; Liu, Hongxuan; Scarborough, Tara; Charaf, Otman; Cooper, Seth; Henderson, Conor; Rumerio, Paolo; Avetisyan, Aram; Bose, Tulika; Fantasia, Cory; Heister, Arno; Lawson, Philip; Lazic, Dragoslav; Rohlf, James; Sperka, David; St John, Jason; Sulak, Lawrence; Alimena, Juliette; Bhattacharya, Saptaparna; Christopher, Grant; Cutts, David; Demiragli, Zeynep; Ferapontov, Alexey; Garabedian, Alex; Heintz, Ulrich; Jabeen, Shabnam; Kukartsev, Gennadiy; Laird, Edward; Landsberg, Greg; Luk, Michael; Narain, Meenakshi; Segala, Michael; Sinthuprasith, Tutanon; Speer, Thomas; Breedon, Richard; Breto, Guillermo; Calderon De La Barca Sanchez, Manuel; Chauhan, Sushil; Chertok, Maxwell; Conway, John; Conway, Rylan; Cox, Peter Timothy; Erbacher, Robin; Gardner, Michael; Houtz, Rachel; Ko, Winston; Kopecky, Alexandra; Lander, Richard; Miceli, Tia; Pellett, Dave; Pilot, Justin; Ricci-Tam, Francesca; Rutherford, Britney; Searle, Matthew; Smith, John; Squires, Michael; Tripathi, Mani; Wilbur, Scott; Yohay, Rachel; Andreev, Valeri; Cline, David; Cousins, Robert; Erhan, Samim; Everaerts, Pieter; Farrell, Chris; Felcini, Marta; Hauser, Jay; Ignatenko, Mikhail; Jarvis, Chad; Rakness, Gregory; Schlein, Peter; Takasugi, Eric; Traczyk, Piotr; Valuev, Vyacheslav; Weber, Matthias; Babb, John; Clare, Robert; Ellison, John Anthony; Gary, J William; Hanson, Gail; Heilman, Jesse; Jandir, Pawandeep; Liu, Hongliang; Long, Owen Rosser; Luthra, Arun; Malberti, Martina; Nguyen, Harold; Paramesvaran, Sudarshan; Shrinivas, Amithabh; Sturdy, Jared; Sumowidagdo, Suharyo; Wilken, Rachel; Wimpenny, Stephen; Andrews, Warren; Branson, James G; Cerati, Giuseppe Benedetto; Cittolin, Sergio; Evans, David; Holzner, André; Kelley, Ryan; Lebourgeois, Matthew; Letts, James; Macneill, Ian; Padhi, Sanjay; Palmer, Christopher; Petrucciani, Giovanni; Pieri, Marco; Sani, Matteo; Sharma, Vivek; Simon, Sean; Sudano, Elizabeth; Tadel, Matevz; Tu, Yanjun; Vartak, Adish; Wasserbaech, Steven; Würthwein, Frank; Yagil, Avraham; Yoo, Jaehyeok; Barge, Derek; Campagnari, Claudio; Danielson, Thomas; Flowers, Kristen; Geffert, Paul; George, Christopher; Golf, Frank; Incandela, Joe; Justus, Christopher; Kovalskyi, Dmytro; Krutelyov, Vyacheslav; Lowette, Steven; Magaña Villalba, Ricardo; Mccoll, Nickolas; Pavlunin, Viktor; Richman, Jeffrey; Rossin, Roberto; Stuart, David; To, Wing; West, Christopher; Apresyan, Artur; Bornheim, Adolf; Bunn, Julian; Chen, Yi; Di Marco, Emanuele; Duarte, Javier; Kcira, Dorian; Ma, Yousi; Mott, Alexander; Newman, Harvey B; Pena, Cristian; Rogan, Christopher; Spiropulu, Maria; Timciuc, Vladlen; Veverka, Jan; Wilkinson, Richard; Xie, Si; Zhu, Ren-Yuan; Azzolini, Virginia; Calamba, Aristotle; Carroll, Ryan; Ferguson, Thomas; Iiyama, Yutaro; Jang, Dong Wook; Liu, Yueh-Feng; Paulini, Manfred; Russ, James; Vogel, Helmut; Vorobiev, Igor; Cumalat, John Perry; Drell, Brian Robert; Ford, William T; Gaz, Alessandro; Luiggi Lopez, Eduardo; Nauenberg, Uriel; Smith, James; Stenson, Kevin; Ulmer, Keith; Wagner, Stephen Robert; Alexander, James; Chatterjee, Avishek; Eggert, Nicholas; Gibbons, Lawrence Kent; Hopkins, Walter; Khukhunaishvili, Aleko; Kreis, Benjamin; Mirman, Nathan; Nicolas Kaufman, Gala; Patterson, Juliet Ritchie; Ryd, Anders; Salvati, Emmanuele; Sun, Werner; Teo, Wee Don; Thom, Julia; Thompson, Joshua; Tucker, Jordan; Weng, Yao; Winstrom, Lucas; Wittich, Peter; Winn, Dave; Abdullin, Salavat; Albrow, Michael; Anderson, Jacob; Apollinari, Giorgio; Bauerdick, Lothar AT; Beretvas, Andrew; Berryhill, Jeffrey; Bhat, Pushpalatha C; Burkett, Kevin; Butler, Joel Nathan; Chetluru, Vasundhara; Cheung, Harry; Chlebana, Frank; Cihangir, Selcuk; Elvira, Victor Daniel; Fisk, Ian; Freeman, Jim; Gao, Yanyan; Gottschalk, Erik; Gray, Lindsey; Green, Dan; Gutsche, Oliver; Hare, Daryl; Harris, Robert M; Hirschauer, James; Hooberman, Benjamin; Jindariani, Sergo; Johnson, Marvin; Joshi, Umesh; Kaadze, Ketino; Klima, Boaz; Kunori, Shuichi; Kwan, Simon; Linacre, Jacob; Lincoln, Don; Lipton, Ron; Lykken, Joseph; Maeshima, Kaori; Marraffino, John Michael; Martinez Outschoorn, Verena Ingrid; Maruyama, Sho; Mason, David; McBride, Patricia; Mishra, Kalanand; Mrenna, Stephen; Musienko, Yuri; Newman-Holmes, Catherine; O'Dell, Vivian; Prokofyev, Oleg; Ratnikova, Natalia; Sexton-Kennedy, Elizabeth; Sharma, Seema; Spalding, William J; Spiegel, Leonard; Taylor, Lucas; Tkaczyk, Slawek; Tran, Nhan Viet; Uplegger, Lorenzo; Vaandering, Eric Wayne; Vidal, Richard; Whitmore, Juliana; Wu, Weimin; Yang, Fan; Yun, Jae Chul; Acosta, Darin; Avery, Paul; Bourilkov, Dimitri; Chen, Mingshui; Cheng, Tongguang; Das, Souvik; De Gruttola, Michele; Di Giovanni, Gian Piero; Dobur, Didar; Drozdetskiy, Alexey; Field, Richard D; Fisher, Matthew; Fu, Yu; Furic, Ivan-Kresimir; Hugon, Justin; Kim, Bockjoo; Konigsberg, Jacobo; Korytov, Andrey; Kropivnitskaya, Anna; Kypreos, Theodore; Low, Jia Fu; Matchev, Konstantin; Milenovic, Predrag; Mitselmakher, Guenakh; Muniz, Lana; Remington, Ronald; Rinkevicius, Aurelijus; Skhirtladze, Nikoloz; Snowball, Matthew; Yelton, John; Zakaria, Mohammed; Gaultney, Vanessa; Hewamanage, Samantha; Linn, Stephan; Markowitz, Pete; Martinez, German; Rodriguez, Jorge Luis; Adams, Todd; Askew, Andrew; Bochenek, Joseph; Chen, Jie; Diamond, Brendan; Gleyzer, Sergei V; Haas, Jeff; Hagopian, Sharon; Hagopian, Vasken; Johnson, Kurtis F; Prosper, Harrison; Veeraraghavan, Venkatesh; Weinberg, Marc; Baarmand, Marc M; Dorney, Brian; Hohlmann, Marcus; Kalakhety, Himali; Yumiceva, Francisco; Adams, Mark Raymond; Apanasevich, Leonard; Bazterra, Victor Eduardo; Betts, Russell Richard; Bucinskaite, Inga; Callner, Jeremy; Cavanaugh, Richard; Evdokimov, Olga; Gauthier, Lucie; Gerber, Cecilia Elena; Hofman, David Jonathan; Khalatyan, Samvel; Kurt, Pelin; Lacroix, Florent; Moon, Dong Ho; O'Brien, Christine; Silkworth, Christopher; Strom, Derek; Turner, Paul; Varelas, Nikos; Akgun, Ugur; Albayrak, Elif Asli; Bilki, Burak; Clarida, Warren; Dilsiz, Kamuran; Duru, Firdevs; Griffiths, Scott; Merlo, Jean-Pierre; Mermerkaya, Hamit; Mestvirishvili, Alexi; Moeller, Anthony; Nachtman, Jane; Newsom, Charles Ray; Ogul, Hasan; Onel, Yasar; Ozok, Ferhat; Sen, Sercan; Tan, Ping; Tiras, Emrah; Wetzel, James; Yetkin, Taylan; Yi, Kai; Barnett, Bruce Arnold; Blumenfeld, Barry; Bolognesi, Sara; Giurgiu, Gavril; Gritsan, Andrei; Hu, Guofan; Maksimovic, Petar; Martin, Christopher; Swartz, Morris; Whitbeck, Andrew; Baringer, Philip; Bean, Alice; Benelli, Gabriele; Kenny III, Raymond Patrick; Murray, Michael; Noonan, Daniel; Sanders, Stephen; Stringer, Robert; Wood, Jeffrey Scott; Barfuss, Anne-Fleur; Chakaberia, Irakli; Ivanov, Andrew; Khalil, Sadia; Makouski, Mikhail; Maravin, Yurii; Saini, Lovedeep Kaur; Shrestha, Shruti; Svintradze, Irakli; Gronberg, Jeffrey; Lange, David; Rebassoo, Finn; Wright, Douglas; Baden, Drew; Calvert, Brian; Eno, Sarah Catherine; Gomez, Jaime; Hadley, Nicholas John; Kellogg, Richard G; Kolberg, Ted; Lu, Ying; Marionneau, Matthieu; Mignerey, Alice; Pedro, Kevin; Peterman, Alison; Skuja, Andris; Temple, Jeffrey; Tonjes, Marguerite; Tonwar, Suresh C; Apyan, Aram; Bauer, Gerry; Busza, Wit; Cali, Ivan Amos; Chan, Matthew; Di Matteo, Leonardo; Dutta, Valentina; Gomez Ceballos, Guillelmo; Goncharov, Maxim; Gulhan, Doga; Kim, Yongsun; Klute, Markus; Lai, Yue Shi; Levin, Andrew; Luckey, Paul David; 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Betchart, Burton; Bodek, Arie; Covarelli, Roberto; de Barbaro, Pawel; Demina, Regina; Eshaq, Yossof; Ferbel, Thomas; Garcia-Bellido, Aran; Goldenzweig, Pablo; Han, Jiyeon; Harel, Amnon; Miner, Daniel Carl; Petrillo, Gianluca; Vishnevskiy, Dmitry; Zielinski, Marek; Bhatti, Anwar; Ciesielski, Robert; Demortier, Luc; Goulianos, Konstantin; Lungu, Gheorghe; Malik, Sarah; Mesropian, Christina; Arora, Sanjay; Barker, Anthony; Chou, John Paul; Contreras-Campana, Christian; Contreras-Campana, Emmanuel; Duggan, Daniel; Ferencek, Dinko; Gershtein, Yuri; Gray, Richard; Halkiadakis, Eva; Hidas, Dean; Lath, Amitabh; Panwalkar, Shruti; Park, Michael; Patel, Rishi; Rekovic, Vladimir; Robles, Jorge; Salur, Sevil; Schnetzer, Steve; Seitz, Claudia; Somalwar, Sunil; Stone, Robert; Thomas, Scott; Thomassen, Peter; Walker, Matthew; Cerizza, Giordano; Hollingsworth, Matthew; Rose, Keith; Spanier, Stefan; Yang, Zong-Chang; York, Andrew; Bouhali, Othmane; Eusebi, Ricardo; Flanagan, Will; Gilmore, Jason; Kamon, Teruki; Khotilovich, Vadim; Montalvo, Roy; Osipenkov, Ilya; Pakhotin, Yuriy; Perloff, Alexx; Roe, Jeffrey; Safonov, Alexei; Sakuma, Tai; Suarez, Indara; Tatarinov, Aysen; Toback, David; Akchurin, Nural; Cowden, Christopher; Damgov, Jordan; Dragoiu, Cosmin; Dudero, Phillip Russell; Kovitanggoon, Kittikul; Lee, Sung Won; Libeiro, Terence; Volobouev, Igor; Appelt, Eric; Delannoy, Andrés G; Greene, Senta; Gurrola, Alfredo; Johns, Willard; Maguire, Charles; Mao, Yaxian; Melo, Andrew; Sharma, Monika; Sheldon, Paul; Snook, Benjamin; Tuo, Shengquan; Velkovska, Julia; Arenton, Michael Wayne; Boutle, Sarah; Cox, Bradley; Francis, Brian; Goodell, Joseph; Hirosky, Robert; Ledovskoy, Alexander; Lin, Chuanzhe; Neu, Christopher; Wood, John; Gollapinni, Sowjanya; Harr, Robert; Karchin, Paul Edmund; Kottachchi Kankanamge Don, Chamath; Lamichhane, Pramod; Sakharov, Alexandre; Belknap, Donald; Borrello, Laura; Carlsmith, Duncan; Cepeda, Maria; Dasu, Sridhara; Duric, Senka; Friis, Evan; Grothe, Monika; Hall-Wilton, Richard; Herndon, Matthew; Hervé, Alain; Klabbers, Pamela; Klukas, Jeffrey; Lanaro, Armando; Loveless, Richard; Mohapatra, Ajit; Mozer, Matthias Ulrich; Ojalvo, Isabel; Perry, Thomas; Pierro, Giuseppe Antonio; Polese, Giovanni; Ross, Ian; Sarangi, Tapas; Savin, Alexander; Smith, Wesley H; Swanson, Joshua

    2013-01-01

    The angular distributions and the differential branching fraction of the decay $B^0 \\to K^*(892)^0 \\mu^+ \\mu^-$ are studied using a data sample corresponding to an integrated luminosity of 5.2 inverse femtobarns collected with the CMS detector at the LHC in pp collisions at $\\sqrt{s}$ = 7 TeV. From more than 400 signal decays, the forward-backward asymmetry of the muons, the $K^*(892)^0$ longitudinal polarization fraction, and the differential branching fraction are determined as a function of the square of the dimuon invariant mass. The measurements are in good agreement with standard model predictions.

  1. Measurement of Branching Fraction and Time-Dependent CP Asymmetry Parameters in B0 -> D*+ D*- Ks Decays

    CERN Document Server

    Dalseno, J; Aihara, H; Aushev, T; Bakich, A M; Balagura, V; Bay, A; Bitenc, U; Bizjak, I; Bozek, A; Bracko, M; Browder, T E; Chao, Y; Chen, A; Cheon, B G; Chistov, R; Cho, I S; Choi, Y; Choi, Y K; Danilov, M; Dash, M; Drutskoy, A; Eidelman, S; Go, A; Ha, H; Hayasaka, K; Hazumi, M; Heffernan, D; Hokuue, T; Hyun, H J; Inami, K; Ishikawa, A; Ishino, H; Iwasaki, M; Iwasaki, Y; Joshi, N J; Kah, D H; Kang, J H; Kapusta, P; Katayama, N; Kawai, H; Kawasaki, T; Kichimi, H; Kim, H J; Kim, Y J; Kinoshita, K; Krizan, P; Krokovnyi, P P; Kumar, R; Kuo, C C; Kuzmin, A; Kwon, Y J; Lee, J S; Lee, S E; Lesiak, T; Li, J; Limosani, A; Lin, S W; Liventsev, D; Mandl, F; Matsumoto, T; McOnie, S; Medvedeva, T; Mitaroff, W A; Miyake, H; Miyata, H; Moloney, G R; Nakano, E; Nakao, M; Nishida, S; Nitoh, O; Ogawa, S; Ohshima, T; Okuno, S; Onuki, Y; Ostrowicz, W; Ozaki, H; Pakhlov, P; Pakhlova, G; Park, C W; Park, H; Park, K S; Pestotnik, R; Piilonen, L E; Sahoo, H; Sakai, Y; Schneider, O; Schümann, J; Seidl, R; Sekiya, A; Senyo, K; Sevior, M E; Shapkin, M; Shibuya, H; Singh, J B; Sokolov, A; Somov, A; Stanic, S; Staric, M; Stöck, H; Sumisawa, K; Sumiyoshi, T; Takasaki, F; Tanaka, M; Taylor, G N; Teramoto, Y; Tian, X C; Tsukamoto, T; Uehara, S; Ueno, K; Uglov, T; Unno, Y; Uno, S; Urquijo, P; Varner, G; Villa, S; Vinokurova, A; Wang, C C; Wang, C H; Watanabe, Y; Wedd, R; Won, E; Yabsley, B D; Yamaguchi, A; Yamashita, Y; Yamauchi, M; Zhang, Z P; Zhilich, V; Zupanc, A

    2007-01-01

    We present a measurement of the branching fraction and time-dependent CP violation parameters for B0 -> D*+ D*- Ks decays. We also obtain an upper limit on the product branching fraction for the possible two-body decay, B0 -> Ds1+(2536) D*-. These results are obtained from a 414 fb-1 data sample that contains 449e10^6 BBbar pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric e+e- collider.

  2. Inelastic neutron scattering studies of Ge-76 and Se-76: relevance to neutrinoless double-beta decay

    Energy Technology Data Exchange (ETDEWEB)

    Crider, Ben [University of Kentucky, Lexington; Peters, Erin [University of Kentucky, Lexington; Ross, T.J. [University of Kentucky, Lexington; McEllistrem, M [University of Kentucky, Lexington; Prados-Estevez, F. [University of Kentucky, Lexington; Allmond, James M [ORNL; Vanhoy, J.R. [U.S. Naval Academy, Annapolis; Yates, S.W. [University of Kentucky, Lexington

    2015-01-01

    Inelastic neutron scattering measurements were performed at the University of Kentucky Accelerator Laboratory on enriched Ge-76 and Se-76 scattering samples. From measurements at incident neutron energies from 2.0 to 4.0 MeV, many new levels were identified and characterized in each nucleus; level lifetimes, transition probabilities, multipole mixing ratios, and other properties were determined. In addition, gamma-ray cross sections for the Ge-76(n,n'gamma) reaction were measured at neutron energies up to 5.0 MeV, with the goal of determining the cross sections of gamma rays in 2040-keV region, which corresponds to the region of interest in the neutrinoless double beta decay of Ge-76. Gamma rays from the three strongest branches from the 3952-keV level were observed, but the previously reported 2041-keV gamma ray was not. Population cross sections across the range of incident neutron energies were determined for the 3952-keV level, resulting in a cross section of similar to 0.1 mb for the 2041-keV branch using the previously determined branching ratios. Beyond this, the data from these experiments indicate that previously unreported gamma rays from levels in Ge-76 can be found in the 2039-keV region.

  3. The 76Ge Double-Beta Decay Experiment GERDA at LNGS

    International Nuclear Information System (INIS)

    In the second generation 76Ge double-beta decay experiment GERDA bare detectors made out of enriched 76Ge will be operated in an cryogenic fluid shield. The goal of the approved GERDA project is to reduce the background around Q = 2039 keV below 10-3 counts/(kg keVy) and reach a sensitivity for neutrinoless ββ decay of T1/2 > 2 x 1026 years after an exposure of 100 kg years. (author)

  4. The low background spectrometer TGV II for double beta decay measurements

    Science.gov (United States)

    Beneš, P.; Čermák, P.; Gusev, K. N.; Klimenko, A. A.; Kovalenko, V. E.; Kovalík, A.; Rukhadze, N. I.; Salamatin, A. V.; Šimkovic, F.; Štekl, I.; Timkin, V. V.; Vylov, Ts.

    2006-12-01

    The low-background multi-HPGe spectrometer TGV II installed in the Modane Underground Laboratory (France) is described in detail and the results of the background measurements are reported. The spectrometer is focused on the double beta decay measurements with two isotopes— 106Cd ( 2νEC/EC mode) and 48Ca ( ββ mode). A basic summary of the physics of ββ decay (especially EC/EC mode) is also given.

  5. The low background spectrometer TGV II for double beta decay measurements

    International Nuclear Information System (INIS)

    The low-background multi-HPGe spectrometer TGVII installed in the Modane Underground Laboratory (France) is described in detail and the results of the background measurements are reported. The spectrometer is focused on the double beta decay measurements with two isotopes-106Cd (2νEC/EC mode) and 48Ca (ββ mode). A basic summary of the physics of ββ decay (especially EC/EC mode) is also given

  6. Recoil ion charge state distribution following the beta(sup +) decay of {sup 21}Na

    Energy Technology Data Exchange (ETDEWEB)

    Scielzo, Nicholas D.; Freedman, Stuart J.; Fujikawa, Brian K.; Vetter, Paul A.

    2003-01-03

    The charge state distribution following the positron decay of 21Na has been measured, with a larger than expected fraction of the daughter 21Ne in positive charge states. No dependence on either the positron or recoil nucleus energy is observed. The data is compared to a simple model based on the sudden approximation. Calculations suggest a small but important contribution from recoil ionization has important consequences for precision beta decay correlation experiments detecting recoil ions.

  7. Recoil ion charge state distribution following the beta(sup +) decay of 21Na

    International Nuclear Information System (INIS)

    The charge state distribution following the positron decay of 21Na has been measured, with a larger than expected fraction of the daughter 21Ne in positive charge states. No dependence on either the positron or recoil nucleus energy is observed. The data is compared to a simple model based on the sudden approximation. Calculations suggest a small but important contribution from recoil ionization has important consequences for precision beta decay correlation experiments detecting recoil ions

  8. The K-Forbidden Beta Decay of Tb160

    DEFF Research Database (Denmark)

    Hansen, P. Gregers; Johnson, N. R.; Nielsen, H. L.

    1964-01-01

    The β decay of the odd nucleus Tb160(Iπ = 3−) is shown to populate the 2+ and 4+ states of the ground-state band of Dy160 in intensities of 0.34% and 0.12%, respectively. The ratio of the reduced transition probabilities and the absolute transition strength are both compared with theoretical...

  9. Free-Neutron Beta-Decay Half-Life

    DEFF Research Database (Denmark)

    Christensen, Carl Jørgen; Nielsen, A.; Bahnsen, A.;

    1972-01-01

    The β-decay half-life of the free neutron was measured. Greater accuracy was obtained through the development of a special 4πβ spectrometer with a well-defined source volume and through the use of a new density calibration method with a 3He proportional counter. A clean thermal-neutron beam was...

  10. Nuclear $\\beta^-$-decay half-lives for $fp$ and $f_{5/2}pg_{9/2}$ shell nuclei

    CERN Document Server

    Kumar, Vikas; Li, Hantao

    2016-01-01

    In the present work we calculate the allowed $\\beta^-$-decay half-lives of nuclei with $Z = 20 -30$ and N $\\leq$ 50 systematically under the framework of the nuclear shell model. A recent study shows that some nuclei in this region belonging to the island of inversion. We perform calculation for $fp$ shell nuclei using KB3G effective interaction. In the case of Ni, Cu, and Zn, we used JUN45 effective interaction. Theoretical results of $Q$ values, half-lives, excitation energies, log$ft$ values, and branching fractions are discussed and compared with experimental data. In Ni region, we also compared our calculated results with recent experimental data [Z. Y. Xu {\\it et al.}, \\emph{Phys. Rev. Lett.} \\textbf{113}, 032505, 2014]. Present results showing good agreement with experimental value of half-lives in comparison to QRPA.

  11. Measurement of branching fraction and CP asymmetries in B->D0(cp)K decays

    CERN Document Server

    Aubert, B; Boutigny, D; Karyotakis, Yu; Lees, J P; Poireau, V; Prudent, X; Tisserand, V; Zghiche, A; Garra Tico, J; Graugès-Pous, E; López, L; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lopes-Pegna, D; Lynch, G; Mir, L M; Orimoto, T J; Osipenkov, I L; Ronan, M T; Tackmann, K; Tanabé, T; Wenzel, W A; Del Amo-Sánchez, P; Hawkes, C M; Watson, A T; Koch, H; Schröder, T; Walker, D; Asgeirsson, D J; Çuhadar-Dönszelmann, T; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Khan, A; Saleem, M; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Liu, F; Long, O; Shen, B C; Vitug, G M; Zhang, L; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Schalk, T; Schumm, B A; Seiden, A; Wilson, M G; Winstrom, L O; Chen, E; Cheng, C H; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Gabareen, A M; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Karbach, M; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Klose, V; Kobel, M J; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Lombardo, V; Thiebaux, C; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Watson, J E; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Franchini, P; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Santoro, V; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; De Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Dauncey, P D; Flack, R L; Nash, J A; Panduro-Vazquez, W; Tibbetts, M; Behera, P K; Chai, X; Charles, M J; Mallik, U; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Lae, C K; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Bequilleux, J; D'Orazio, A; Davier, M; Grosdidier, G; Höcker, A; Lepeltier, V; Le Diberder, F; Lutz, A M; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wang, W F; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Burke, J P; Chavez, C A; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; George, K A; Di Lodovico, F; Sacco, R; Cowan, G; Flächer, H U; Hopkins, D A; Paramesvaran, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Bailey, D; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Salvati, E; Saremi, S; Cowan, R; Dujmic, D; Fisher, P H; Koeneke, K; Sciolla, G; Spitznagel, M; Taylor, F; Yamamoto, R K; Zhao, M; Zheng, Y; Mclachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; De Nardo, Gallieno; Fabozzi, F; Lista, L; Monorchio, D; Sciacca, C; Baak, M A; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; LoSecco, J M; Benelli, G; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Sekula, S J; Wong, Q K; Blount, N L; Brau, J E; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gagliardi, N; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Ben-Haim, E; Briand, H; Calderini, G; Chauveau, J; David, P; Del Buono, L; De La Vaissière, C; Hamon, O; Leruste, P; Malcles, J; Ocariz, J; Pérez, A; Prendki, J; Gladney, L; Biasini, M; Covarelli, R; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Carpinelli, M; Cenci, R; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Mazur, M A; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Biesiada, J; Elmer, P; Lau, Y P; Lü, C; Olsen, J; Smith, A J S; Telnov, A V; Baracchini, E; Bellini, F; Cavoto, G; Del Re, D; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Renga, F; Voena, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Castelli, G; Franek, B; Olaiya, E O; Röthel, W; Wilson, F F; Emery, S; Escalier, M; Gaidot, A; Ganzhur, S F; Hamel de Monchenault, G; Kozanecki, W; Vasseur, G; Yéche, C; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; White, R M; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Bechtle, P; Claus, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Glanzman, T; Gowdy, S J; Graham, M T; Grenier, P; Hast, C; Innes, W R; Kaminski, J; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Luitz, S; Lüth, V; Lynch, H L; MacFarlane, D B; Marsiske, H; Messner, R; Müller, D R; O'Grady, C P; Ofte, I; Perazzo, A; Perl, M; Pulliam, T; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Vavra, J; Wagner, A P; Weaver, M; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Yi, K; Young, C C; Ziegler, V; Burchat, P R; Edwards, A J; Majewski, S A; Miyashita, T S; Petersen, B A; Wilden, L; Ahmed, S; Alam, M S; Bula, R; Ernst, J A; Jain, V; Pan, B; Saeed, M A; Wappler, F R; Zain, S B; Krishnamurthy, M; Spanier, S M; Eckmann, R; Ritchie, J L; Ruland, A M; Schilling, C J; Schwitters, R F; Izen, J M; Lou, X C; Ye, S; Bianchi, F; Gallo, F; Gamba, D; Pelliccioni, M; Bomben, M; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martínez-Vidal, F; Milanes, D A; Oyanguren, A; Albert, J; Banerjee, Sw; Bhuyan, B; Hamano, K; Kowalewski, R; Nugent, I M; Roney, J M; Sobie, R J; Harrison, P F; Ilic, J; Latham, T E; Mohanty, G B; Band, H R; Chen, X; Dasu, S; Flood, K T; Hollar, J J; Kutter, P E; Pan, Y; Pierini, M; Prepost, R; Wu, S L; Neal, H

    2007-01-01

    We present a preliminary study of $B^- \\to D^0_{CP} \\pi^-$ and $B^- \\to D^0_{CP} K^-$ decays, with the $D^0_{CP}$ reconstructed in the CP-odd eigenstates $K_s \\pi^0$, $K_s \\omega$, in the CP-even eigenstates $K^+ K^-$, $\\pi^+ \\pi^-$, and in the (non-CP) flavor eigenstate $K^\\mp \\pi^\\pm$. Using a sample of about 382 million Y(4S) decays into BBbar pairs, collected with the BABAR detector operating at the PEP-II asymmetric-energy B Factory at SLAC, we measure the ratios of the branching fractions R_CP+- and the direct CP asymmetries A_CP+-. The results are: R_CP- = 0.81 \\pm 0.10 (stat) \\pm 0.05 (syst) R_CP+ = 1.07 \\pm 0.10 (stat) \\pm 0.04 (syst) A_CP- = -0.19 \\pm 0.12 (stat) \\pm 0.02 (syst) A_CP+ = 0.35 \\pm 0.09 (stat) \\pm 0.05 (syst)

  12. Neutrinoless double beta decay experiment DCBA using a magnetic momentum-analyzer

    Energy Technology Data Exchange (ETDEWEB)

    Ishihara, N., E-mail: nobuhiro.ishihara@kek.jp [High Energy Accelerator Research Organization (KEK), Tsukuba, 305-0801 (Japan); Kato, Y.; Inagaki, T.; Ohama, T.; Takeda, S.; Yamada, Y. [High Energy Accelerator Research Organization (KEK), Tsukuba, 305-0801 Japan (Japan); Ukishima, N.; Teramoto, Y. [Osaka City University, Sumiyoshi, Osaka, 558-8585 (Japan); Morishima, Y.; Nakano, I. [Okayama University, Okayama, 700-8530 (Japan); Kitamura, S. [Tokyo Metropolitan University, Arakawa, Tokyo, 116-8551 (Japan); Sakamoto, Y. [Tohoku Gakuin University, Izumi, Sendai, 981-3193 (Japan); Nagasaka, Y. [Hiroshima Institute of Technology, Saeki, Hiroshima, 731-5193 (Japan); Tamura, N. [Niigata University, Niigata, 950-2181 (Japan); Tanaka, K. [BTE, Minato, Tokyo, 105-0011 (Japan); Ito, R. [ZTJ, Chiyoda, Tokyo, 101-0047 (Japan)

    2011-12-15

    A magnetic momentum-analyzer is being developed at KEK for neutrinoless double beta decay experiment called DCBA (Drift Chamber Beta-ray Analyzer, inverted ABCD). A lot of thin plates of {sup 150}Nd compound are installed in tracking detectors located in a uniform magnetic field. The three-dimensional position information is obtained for the helical track of a beta ray. More R and D will be studied using the second test apparatus DCBA-T2, which is now under construction.

  13. The search for Majorana neutrinos with neutrinoless double beta decays: From CUORICINO to LUCIFER experiment

    Energy Technology Data Exchange (ETDEWEB)

    Bellini, F. [Dipartimento di Fisica, Sapienza Universita di Roma, Roma I-00185 (Italy) and INFN - Sezione di Roma, Roma I-00185 (Italy)

    2012-11-20

    The study of neutrino properties is one of the fundamental challenges in particle physics nowadays. Fifty years of investigations established that neutrinos are massive but the absolute mass scale has not yet been measured. Moreover its true nature is still unknown. Is the neutrino its own antiparticle (thus violating the lepton number) as proposed by Majorana in 1937? The only way to probe the neutrino nature is through the observation of Neutrinoless Double Beta Decay (0{nu}{beta}{beta}), a very rare spontaneous nuclear transition which emits two electrons and no neutrinos. In this paper, after a brief introduction to the theoretical framework of Majorana's neutrino, a presentation of experimental challenges posed by 0{nu}{beta}{beta} search will be given as well as an overview of present status and future perpectives of experiments.

  14. Asympotic behavior of the total length of external branches for Beta-coalescents

    CERN Document Server

    Dhersin, Jean-Stephane

    2012-01-01

    We consider a ${\\Lambda}$-coalescent and we study the asymptotic behavior of the total length $L^{(n)}_{ext}$ of the external branches of the associated $n$-coalescent. For Kingman coalescent, i.e. ${\\Lambda}={\\delta}_0$, the result is well known and is useful, together with the total length $L^{(n)}$, for Fu and Li's test of neutrality of mutations% under the infinite sites model asumption . For a large family of measures ${\\Lambda}$, including Beta$(2-{\\alpha},{\\alpha})$ with $0<\\alpha<1$, M{\\"o}hle has proved asymptotics of $L^{(n)}_{ext}$. Here we consider the case when the measure ${\\Lambda}$ is Beta$(2-{\\alpha},{\\alpha})$, with $1<\\alpha<2$. We prove that $n^{{\\alpha}-2}L^{(n)}_{ext}$ converges in $L^2$ to $\\alpha(\\alpha-1)\\Gamma(\\alpha)$. As a consequence, we get that $L^{(n)}_{ext}/L^{(n)}$ converges in probability to $2-\\alpha$. To prove the asymptotics of $L^{(n)}_{ext}$, we use a recursive construction of the $n$-coalescent by adding individuals one by one. Asymptotics of the distributi...

  15. New limits on double beta decay of 106Cd

    Science.gov (United States)

    Rukhadze, N. I.; Bakalyarov, A. M.; Briançon, Ch.; Brudanin, V. B.; Čermák, P.; Egorov, V. G.; Klimenko, A. A.; Kovalík, A.; Lebedev, V. I.; Mamedov, F.; Shitov, Yu. A.; Šimkovic, F.; Štekl, I.; Timkin, V. V.; Zhukov, S. V.

    2011-02-01

    Investigation of double electron capture in 106Cd was performed at the Modane underground laboratory (4800 m.w.e.) using the multi-detector spectrometer TGV-2. In Phase I of the experiment, ˜10 g of 106Cd with an enrichment of 75% was measured during 8687 hours. In Phase II, the TGV-2 background was significantly suppressed in comparison with Phase I and the 106Cd mass was increased to ˜13.6 g. New half-life limits (at 90% CL) were obtained for 2νEC/EC decay of 106Cd to the ground state of Pd106 - T1/2>3.0×10 y (Phase I) and T1/2>3.6×10 y (Phase II, 9000 hours), and for 0νEC/EC decay of 106Cd to the 2741 keV excited state of Pd106 - T1/2>1.1×10 y (Phase II).

  16. Beta-alpha correlation in the decay of 20Na

    International Nuclear Information System (INIS)

    The β-α angular correlation has been measured in the allowed positron decay of 20Na to the 7.42 MeV state of 20Ne. The correlation is of the form 1+a(mean)cos(theta) + p(mean)cos2(theta). p(mean)=-0.003+-0.005 is found in reasonable agreement with expectations based on the conserved vector current theory. (Auth.)

  17. The isospin mixing and the superallowed Fermi beta decay

    Indian Academy of Sciences (India)

    A E Çalik; M Gerçekliğlu; D I Salamov

    2012-09-01

    In the present work, the isospin admixtures in the nuclear ground states of the parent nuclei and isospin structure of the isobar analog resonance (IAR) states have been investigated by studying the 0+ → 0+ superallowed Fermi decays using Pyatov’s restoration method. Within the random phase approximation (RPA), in this method, the effect of isospin breaking due to the Coulomb forces has been evaluated, taking into account the effect of pairing correlations between nucleons.

  18. A Measurement of the Branching Fractions ofexclusive Bbar to D(*)(pi)lnu Decays in Events with a Fully Reconstructed BMeson

    Energy Technology Data Exchange (ETDEWEB)

    Aubert, B.

    2008-01-08

    The authors report a measurement of the branching fractions for {bar B} {yields} D{sup (*)}{pi}{ell}{sup -}{bar {nu}}{sub {ell}} decays based on 341.1 fb{sup -1} of data collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II e{sup +}e{sup -} storage rings. Events are tagged by fully reconstructing one of the B mesons in a hadronic decay mode. The obtain {Beta}(B{sup -} {yields} D{sup 0}{ell}{sup -}{bar {nu}}{sub {ell}}) = (2.33 {+-} 0.09{sub stat.} {+-} 0.09{sub syst.})%, {Beta}(B{sup -} {yields} D*{sup 0}{ell}{sup -}{bar {nu}}{sub {ell}}) = 5.83 {+-} 0.15{sub stat.} {+-} 0.30{sub syst.}%, {Beta}({bar B}{sup 0} {yields} D{sup +}{ell}{sup -}{bar {nu}}{sub {ell}}) = (2.21 {+-} 0.11{sub stat.} {+-} 0.12{sub syst.})% {Beta}({bar B}{sup 0} {yields} D*{sup +}{ell}{sup -}{bar {nu}}{sub {ell}}) = 5.49 {+-} 0.16{sub stat.} {+-} 0.25{sub syst.}%, {Beta}(B{sup -} {yields} D{sup +}{pi}{sup -}{ell}{sup -}{bar {nu}}{sub {ell}}) = (0.42 {+-} 0.06{sub stat.} {+-} 0.03{sub syst.})%, {Beta}(B{sup -} {yields} D*{sup +} {pi}{sup -}{ell}{sup -}{bar {nu}}{sub {ell}}) = (0.59 {+-} 0.05{sub stat.} {+-} 0.04{sub syst.})%, {Beta}({bar B}{sup 0} {yields} D{sup 0}{pi}{sup +}{ell}{sup -}{bar {nu}}{sub {ell}}) = (0.43 {+-} 0.08{sub stat.} {+-} 0.03{sub syst.})% and {Beta}({bar B}{sup 0} {yields} D*{sup 0} {pi}{sup +}{ell}{sup -}{bar {nu}}{sub {ell}}) = (0.48 {+-} 0.08{sub stat.} {+-} 0.04{sub syst.})%.

  19. Beta decay measurements with ultracold neutrons: a review of recent measurements and the research program at Los Alamos National Laboratory

    International Nuclear Information System (INIS)

    We present a review of the motivation and results of recent experiments which utilize ultracold neutrons for measurements of neutron beta decay. Because these experiments hinge critically on the available ultracold neutron source technology, we also review the status of ultracold neutron source development, emphasizing the Los Alamos ultracold neutron facility and the ongoing beta decay research program sited there. (paper)

  20. Stellar $\\beta^{\\pm}$ decay rates of iron isotopes and its implications in astrophysics

    CERN Document Server

    Nabi, Jameel-Un

    2014-01-01

    $\\beta$-decay and positron decay are believed to play a consequential role during the late phases of stellar evolution of a massive star culminating in a supernova explosion. Recently the microscopic calculation of weak-interaction mediated rates on key isotopes of iron was introduced using the proton-neutron quasiparticle random phase approximation (pn-QRPA) theory with improved model parameters. Here I discuss in detail the improved calculation of $\\beta^{\\pm}$ decay rates for iron isotopes ($^{54,55,56}$Fe) in stellar environment. The pn-QRPA theory allows a microscopic "state-by-state" calculation of stellar rates as explained later in text. Excited state Gamow-Teller distributions are much different from ground state and a microscopic calculation of decay rates from these excited states greatly increases the reliability of the total decay rate calculation specially during the late stages of stellar evolution. The reported decay rates are also compared with earlier calculations. The positron decay rates a...

  1. Pions in nuclei and manifestations of supersymmetry in neutrinoless double beta decay

    International Nuclear Information System (INIS)

    We examine the pion realization of the short ranged supersymmetric (SUSY) mechanism of neutrinoless double beta decay (0νββ-decay). It originates from the R-parity violating quark-lepton interactions of the SUSY extensions of the standard model of the electroweak interactions. We argue that pions are dominant SUSY mediators in 0νββ-decay. The corresponding nuclear matrix elements for potentially 0νββ-decaying isotopes are calculated within the proton-neutron renormalized quasiparticle random phase approximation (pn-RQRPA). We define those isotopes which are most sensitive to the SUSY signal and outlook the present experimental situation with the 0νββ-decay searches for the SUSY. Upper limits on the R-parity violating 1st generation Yukawa coupling λ'111 are derived from various 0νββ - experiments

  2. New concepts for a gaseous Xenon detector for double beta decay

    International Nuclear Information System (INIS)

    Xenon gas is an attractive medium for the search for neutrinoless double beta decay because it offers the possibility of reasonable energy resolution, event topology reconstruction, very high intrinsic purity and background rejection through the identification of the daughter barium ion. This talk explores recent developments in the conceptual design of such a detector.

  3. Measurement of double beta decay of 100Mo to excited states in the NEMO 3 experiment

    International Nuclear Information System (INIS)

    The double beta decay of 100Mo to the 01+ and 21+ excited states of 100Ru is studied using the NEMO 3 data. After the analysis of 8024 h of data the half-life for the two-neutrino double beta decay of 100Mo to the excited 01+ state is measured to be T1/2(2ν)=[5.7-0.9+1.3(stat.)+/-0.8(syst.)]x1020 y. The signal-to-background ratio is equal to 3. Information about energy and angular distributions of emitted electrons is also obtained. No evidence for neutrinoless double beta decay to the excited 01+ state has been found. The corresponding half-life limit is T1/2(0ν)(0+->01+)>8.9x1022 y (at 90% C.L.). The search for the double beta decay to the 21+ excited state has allowed the determination of limits on the half-life for the two neutrino mode T1/2(2ν)(0+->21+)>1.1x1021 y (at 90% C.L.) and for the neutrinoless mode T1/2(0ν)(0+->21+)>1.6x1023 y (at 90% C.L.)

  4. The status of the IGEX 76Ge double-beta decay experiment in 1997

    International Nuclear Information System (INIS)

    The International Germanium Experiment (IGEX) has six detectors containing ∼ 90 fiducial moles of 76Ge. Data from 74.84 fiducial mole years yield a lower bound T0ν1/2>0.8x1025 y for neutrinoless double-beta decay of 76Ge

  5. Status of double beta decay experiments using isotopes other than Xe-136

    CERN Document Server

    Pandola, Luciano

    2014-01-01

    Neutrinoless double beta decay is a lepton-number violating process predicted by many extensions of the standard model. It is actively searched for in several candidate isotopes within many experimental projects. The status of the experimental initiatives which are looking for the neutrinoless double beta decay in isotopes other than Xe-136 is reviewed, with special emphasis given to the projects that passed the R&D phase. The results recently released by the experiment GERDA are also summarized and discussed. The GERDA data give no positive indication of neutrinoless double beta decay of Ge-76 and disfavor in a model-independent way the long-standing observation claim on the same isotope. The lower limit reported by GERDA for the half-life of neutrinoless double beta decay of Ge-76 is T1/2 > 2.1e25 yr (90% C.L.), or T1/2 > 3.0e25 yr, when combined with the results of other Ge-76 predecessor experiments.

  6. Neutrinoless Double Beta Decay in Type I+II Seesaw Models

    CERN Document Server

    Borah, Debasish

    2015-01-01

    We study neutrinoless double beta decay in left-right symmetric extension of the standard model with type I and type II seesaw origin of neutrino masses. Due to the enhanced gauge symmetry as well as extended scalar sector, there are several new physics sources of neutrinoless double beta decay in this model. Ignoring the left-right gauge boson mixing and heavy-light neutrino mixing, we first compute the contributions to neutrinoless double beta decay for type I and type II dominant seesaw separately and compare with the standard light neutrino contributions. We then repeat the exercise by considering the presence of both type I and type II seesaw, having non-negligible contributions to light neutrino masses and show the difference in results from individual seesaw cases. Assuming the new gauge bosons and scalars to be around a TeV, we constrain different parameters of the model including both heavy and light neutrino masses from the requirement of keeping the neutrinoless double beta decay amplitude below th...

  7. Measurement of double beta decay of 100Mo to excited states in the NEMO 3 experiment

    CERN Document Server

    Arnold, R; Baker, J; Barabash, A S; Bongrand, M; Broudin, G; Brudanin, V; Caffrey, A J; Egorov, V; Etienvre, A I; Fatemi-Ghomi, N; Hubert, F; Hubert, P; Jerie, J; Jollet, C; Jullian, S; King, S; Kochetov, O; Konovalov, S I; Kovalenko, V; Lalanne, D; Lamhamdi, T; Leccia, F; Lemière, Y; Longuemare, C; Lutter, G; Marquet, C; Mauger, F; Nachab, A; Ohsumi, H; Perrot, F; Piquemal, F; Reyss, J L; Ricol, J S; Saakyan, R; Sarazin, X; Shitov, Y; Simard, L; Simkovic, F; Smolnikov, A; Stekl, I; Suhonen, J; Sutton, C S; Szklarz, G; Söldner-Rembold, S; Thomas, J; Timkin, V; Tretyak, V; Umatov, V; Vanyushin, I A; Vasilev, V; Vorobel, V; Vylov, T; Vàla, L; Hubert, Ph.; Marquet, Ch.; Shitov, Yu.; Vylov, Ts.

    2007-01-01

    The double beta decay of 100Mo to the 0^+_1 and 2^+_1 excited states of 100Ru is studied using the NEMO 3 data. After the analysis of 8024 h of data the half-life for the two-neutrino double beta decay of 100Mo to the excited 0^+_1 state is measured to be T^(2nu)_1/2 = [5.7^{+1.3}_{-0.9}(stat)+/-0.8(syst)]x 10^20 y. The signal-to-background ratio is equal to 3. Information about energy and angular distributions of emitted electrons is also obtained. No evidence for neutrinoless double beta decay to the excited 0^+_1 state has been found. The corresponding half-life limit is T^(0nu)_1/2(0^+ --> 0^+_1) > 8.9 x 10^22 y (at 90% C.L.). The search for the double beta decay to the 2^+_1 excited state has allowed the determination of limits on the half-life for the two neutrino mode T^(2nu)_1/2(0^+ --> 2^+_1) > 1.1 x 10^21 y (at 90% C.L.) and for the neutrinoless mode T^(0nu)_1/2(0^+ --> 2^+_1) > 1.6 x 10^23 y (at 90% C.L.).

  8. New physics in the new millennium with GENIUS: double beta decay, dark matter, solar neutrinos

    International Nuclear Information System (INIS)

    Double beta decay is indispensable to solve the question of the neutrino mass matrix together with ν oscillation experiments. The most sensitive experiment since eight years - the HEIDELBERG - MOSCOW experiment in Gran Sasso - already now, with the experimental limit of ν> 7Be) solar neutrinos. A GENIUS Test Facility has just been funded and will come into operation by the end of 2001

  9. Double Beta Decays into Excited States in $^{110}$Pd and $^{102}$Pd

    CERN Document Server

    Lehnert, B; Degering, D; Hult, M; Laubenstein, M; Wester, T; Zuber, K

    2016-01-01

    A search for double beta decays of $^{110}$Pd and $^{102}$Pd into excited states of the daughter nuclides has been performed using three ultra-low background gamma-spectrometry measurements in the Felsenkeller laboratory, Germany, the HADES laboratory, Belgium and at the LNGS, Italy. The combined Bayesian analysis of the three measurements sets improved half-life limits for the $2\

  10. New physics effects on neutrinoless double beta decay from right-handed current

    Science.gov (United States)

    Ge, Shao-Feng; Lindner, Manfred; Patra, Sudhanwa

    2015-10-01

    We study the impact of new physics contributions to neutrinoless double beta decay arising from right-handed current in comparison with the standard mechanism. If the light neutrinos obtain their masses from Type-II seesaw within left-right symmetric model, where the Type-I contribution is suppressed to negligible extent, the right-handed PMNS matrix is the same as its left-handed counterpart, making it highly predictable and testable at next-generation experiments. It is very attractive, especially with recent cosmological constraint favoring the normal hierarchy under which the neutrinoless double beta decay is too small to be observed unless new physics appears as indicated by the recent diboson excess observed at ATLAS. The relative contributions from left- and right-handed currents can be reconstructed with the ratio between lifetimes of two different isotopes as well as the ratio of nuclear matrix elements. In this way, the theoretical uncertainties in the calculation of nuclear matrix elements can be essentially avoided. We also discuss the interplay of neutrinoless double beta decay measurements with cosmology, beta decay, and neutrino oscillation.

  11. Measurement of the background in the NEMO 3 double beta decay experiment

    CERN Document Server

    Argyriades, J; Augier, C; Baker, J; Barabash, A S; Bongrand, M; Broudin-Bay, G; Brudanin, V B; Caffrey, A J; Chapon, A; Chauveau, E; Daraktchieva, Z; Durand, D; Egorov, V G; Fatemi-Ghomi, N; Flack, R; Freshville, A; Guillon, B; Hubert, Ph; Jullian, S; Kauer, M; King, S; Kochetov, O I; Konovalov, S I; Kovalenko, V E; Lalanne, D; Lang, K; Lemi`ere, Y; Lutter, G; Mamedov, F; Marquet, Ch; Martín-Albo, J; Mauger, F; Nachab, A; Nasteva, I; Nemchenok, I B; Nova, F; Novella, P; Ohsumi, H; Pahlka, R B; Perrot, F; Piquemal, F; Reyss, J L; Ricol, J S; Saakyan, R; Sarazin, X; Simard, L; Shitov, Yu A; Smolnikov, A A; Snow, S; Söldner-Rembold, S; Stekl, I; Sutton, C S; Szklarz, G; Thomas, J; Timkin, V V; Tretyak, V I; Tretyak, Vl I; Umatov, V I; Vàla, L; Vanyushin, I A; Vasiliev, V A; Vorobel, V; Vylov, Ts

    2009-01-01

    In the double beta decay experiment NEMO~3 a precise knowledge of the background in the signal region is of outstanding importance. This article presents the methods used in NEMO~3 to evaluate the backgrounds resulting from most if not all possible origins. It also illustrates the power of the combined tracking-calorimetry technique used in the experiment.

  12. Inverse neutrinoless double $\\beta$ decay and other $\\Delta$ L=2 processes

    CERN Document Server

    London, D

    1999-01-01

    I review the prospects for the detection of Delta L=2 processes at future colliders. Except in contrived models, the process e- e- -> W- W- is unobservable at future linear colliders unless $\\sqrt{s} \\gsim 2$ TeV, due to constraints from neutrinoless double beta decay. As there are no analogous constraints on the Majorana mass of the $\

  13. New concepts for a gaseous Xenon detector for double beta decay

    Science.gov (United States)

    Sinclair, D.; Exo Collaboration

    2010-01-01

    Xenon gas is an attractive medium for the search for neutrinoless double beta decay because it offers the possibility of reasonable energy resolution, event topology reconstruction, very high intrinsic purity and background rejection through the identification of the daughter barium ion. This talk explores recent developments in the conceptual design of such a detector.

  14. Experiment TGV-2 - Search for double beta decay of 106Cd

    Science.gov (United States)

    Rukhadze, N. I.; Briançon, Ch.; Brudanin, V. B.; Čermák, P.; Egorov, V. G.; Klimenko, A. A.; Kovalík, A.; Rukhadze, E. N.; Shitov, Yu. A.; Šimkovic, F.; Štekl, I.; Timkin, V. V.

    2012-08-01

    New limits (at 90% C.L.) on double beta decay of Cd106-T(0νEC/EC)>1.7×1020 yr and T(2νEC/EC)>4.2×1020 yr were obtained in a preliminary calculation of data accumulated for 12900 h on the TGV-2 spectrometer.

  15. Present status and future of the experiment TGV (measurement of double beta decay of48Ca)

    Science.gov (United States)

    Brudanin, V. B.; Egorov, V. G.; Kovalík, A.; Kovalenko, V. E.; Rukhadze, N. I.; Salamatin, A. V.; Sandukovsky, V. G.; Timkin, V. V.; Vylov, Ts.; Zaparov, Ch.; Briancon, Ch.; Janout, Z.; Koníček, J.; Kubašta, J.; Pospíšil, S.; Štekl, I.; Vorobel, V.

    1998-02-01

    A short description of experiment TGV (double beta decay of48Ca) is given. The measurement started in the Modane underground laboratory in August 1996. The first result of T {1/2/0 ν } ≥ 4.6 × 1020 years [90% CL] after 2545 hours is presented.

  16. Present status and future of the experiment TGV (measurement of double beta decay of 48Ca)

    International Nuclear Information System (INIS)

    A short description of experiment TGV (double beta decay of 48Ca) is given. The measurement started in the Modane underground laboratory in August 1996. The first result of T1/20ν ≥ 4.6 x 1020 years [90% CL] after 2545 hours is presented. (author)

  17. Experiment TGV-2 – Search for double beta decay of 106Cd

    International Nuclear Information System (INIS)

    New limits (at 90% C.L.) on double beta decay of 106Cd−T1/2(0νEC/EC)>1.7×1020yr and T1/2(2νEC/EC)>4.2×1020yr were obtained in a preliminary calculation of data accumulated for 12900 h on the TGV-2 spectrometer.

  18. Spectral distribution Method for neutrinoless double beta decay: Results for $^{82}$Se and $^{76}$Ge

    CERN Document Server

    Kota, V K B

    2016-01-01

    Statistical spectral distribution method based on shell model and random matrix theory is developed for calculating neutrinoless double beta decay nuclear transition matrix elements. First results obtained for $^{82}$Se and $^{76}$Ge using the spectral method are close to the available shell model results.

  19. Statistical criteria for possible indications of new physics in tritium $\\beta$-decay spectrum

    CERN Document Server

    Lokhov, Aleksei

    2014-01-01

    The method of quasi-optimal weights is applied to constructing (quasi-)optimal criteria for various anomalous contributions in experimental spectra. Anomalies in the spectra could indicate physics beyond the Standard Model (additional interactions and neutrino flavours, Lorenz violation etc.). In particular the cumulative tritium $\\beta$-decay spectrum (for instance, in Troitsk-$\

  20. Neutrinoless double beta decay in type I+II seesaw models

    Science.gov (United States)

    Borah, Debasish; Dasgupta, Arnab

    2015-11-01

    We study neutrinoless double beta decay in left-right symmetric extension of the standard model with type I and type II seesaw origin of neutrino masses. Due to the enhanced gauge symmetry as well as extended scalar sector, there are several new physics sources of neutrinoless double beta decay in this model. Ignoring the left-right gauge boson mixing and heavy-light neutrino mixing, we first compute the contributions to neutrinoless double beta decay for type I and type II dominant seesaw separately and compare with the standard light neutrino contributions. We then repeat the exercise by considering the presence of both type I and type II seesaw, having non-negligible contributions to light neutrino masses and show the difference in results from individual seesaw cases. Assuming the new gauge bosons and scalars to be around a TeV, we constrain different parameters of the model including both heavy and light neutrino masses from the requirement of keeping the new physics contribution to neutrinoless double beta decay amplitude below the upper limit set by the GERDA experiment and also satisfying bounds from lepton flavor violation, cosmology and colliders.

  1. Limits on the neutrino mass from neutrinoless double-$\\beta $ decay

    CERN Document Server

    Barea, J; Iachello, F

    2015-01-01

    Neutrinoless double-$\\beta$ decay is of fundamental importance for the determining neutrino mass. By combining a calculation of nuclear matrix elements within the framework of the microscopic interacting boson model (IBM-2) with an improved calculation of phase space factors, we set limits on the average light neutrino mass and on the average inverse heavy neutrino mass (flavor violating parameter).

  2. Measurement of the background in the NEMO 3 double beta decay experiment

    International Nuclear Information System (INIS)

    In the double beta decay experiment NEMO 3 a precise knowledge of the background in the signal region is of outstanding importance. This article presents the methods used in NEMO 3 to evaluate the backgrounds resulting from most if not all possible origins. It also illustrates the power of the combined tracking-calorimetry technique used in the experiment.

  3. Status of the Frejus experiment on the neutrinoless double beta decay of the 76Ge

    International Nuclear Information System (INIS)

    A brief account of the design, experimental set up and status of the Frejus experiments on the neutrinoless double beta decay of 76Ge is presented. The theoretical implications and expectatives of this experimental research are analized. A comparison with other dedicated experiments is also reported. (author)

  4. First observation of $\\beta$-delayed $\\gamma$-proton decay in the $T_z$ = -2, $^{56}$Zn nucleus

    CERN Document Server

    Orrigo, S E A; Fujita, Y; Blank, B; Gelletly, W; Agramunt, J; Algora, A; Ascher, P; Bilgier, B; Cáceres, L; Cakirli, R B; Fujita, H; Ganioğlu, E; Gerbaux, M; Giovinazzo, J; Grévy, S; Kamalou, O; Kozer, H C; Kucuk, L; Kurtukian-Nieto, T; Molina, F; Popescu, L; Rogers, A M; Susoy, G; Stodel, C; Suzuki, T; Tamii, A; Thomas, J C

    2014-01-01

    We report on the first experimental observation of a very exotic decay mode at the proton drip-line, the $\\beta$-delayed $\\gamma$-proton decay, clearly seen in the $\\beta$ decay of the $T_z$ = -2, $^{56}$Zn nucleus. The $^{56}$Zn half-life and decay scheme have been determined. The decay proceeds by $\\beta$-delayed proton emission and $\\beta$-delayed $\\gamma$ de-excitation. The exotic $\\beta$-delayed $\\gamma$-proton emission was also detected in three cases. It affects the usual determination of the Gamow-Teller (GT) strength. Absolute Fermi and GT strengths have been deduced. Evidence for fragmentation of the Fermi strength due to isospin mixing is found.

  5. Nuclear $\\beta^+$/EC decays in covariant density functional theory and the impact of isoscalar proton-neutron pairing

    CERN Document Server

    Niu, Z M; Liu, Q; Liang, H Z; Guo, J Y

    2013-01-01

    Self-consistent proton-neutron quasiparticle random phase approximation based on the spherical nonlinear point-coupling relativistic Hartree-Bogoliubov theory is established and used to investigate the $\\beta^+$/EC-decay half-lives of neutron-deficient Ar, Ca, Ti, Fe, Ni, Zn, Cd, and Sn isotopes. The isoscalar proton-neutron pairing is found to play an important role in reducing the decay half-lives, which is consistent with the same mechanism in the $\\beta$ decays of neutron-rich nuclei. The experimental $\\beta^+$/EC-decay half-lives can be well reproduced by a universal isoscalar proton-neutron pairing strength.

  6. Double-beta decay investigation with highly pure enriched {sup 82}Se for the LUCIFER experiment

    Energy Technology Data Exchange (ETDEWEB)

    Beeman, J.W. [Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Bellini, F.; Casali, N.; Ferroni, F.; Piperno, G. [Sapienza Universita di Roma, Dipartimento di Fisica, Rome (Italy); INFN, Sezione di Roma, Rome (Italy); Benetti, P. [Universita di Pavia, Dipartimento di Chimica, Pavia (Italy); INFN, Sezione di Pavia, Pavia (Italy); Cardani, L. [Sapienza Universita di Roma, Dipartimento di Fisica, Rome (Italy); Princeton University, Physics Department, Princeton, NJ (United States); Chiesa, D.; Clemenza, M.; Gironi, L.; Maino, M. [Universita di Milano-Bicocca, Dipartimento di Fisica, Milan (Italy); INFN, Sezione di Milano Bicocca, Milan (Italy); Dafinei, I.; Orio, F.; Tomei, C.; Vignati, M. [INFN, Sezione di Roma, Rome (Italy); Di Domizio, S. [INFN, Sezione di Genova, Genoa (Italy); Universita di Genova, Dipartimento di Fisica, Genoa (Italy); Giuliani, A. [Centre de Spectrometrie de Masse, Orsay (France); Gotti, C.; Pessina, G.; Previtali, E.; Rusconi, C. [INFN, Sezione di Milano Bicocca, Milan (Italy); Laubenstein, M.; Nisi, S.; Pattavina, L.; Pirro, S.; Schaeffner, K. [INFN, Laboratori Nazionali del Gran Sasso, Assergi (L' Aquila) (Italy); Nagorny, S.; Pagnanini, L. [Gran Sasso Science Institute, L' Aquila (Italy); Nones, C. [SPP Centre de Saclay, CEA, Irfu, Gif-sur-Yvette (France)

    2015-12-15

    The LUCIFER project aims at deploying the first array of enriched scintillating bolometers for the investigation of neutrinoless double-beta decay of {sup 82}Se. The matrix which embeds the source is an array of ZnSe crystals, where enriched {sup 82}Se is used as decay isotope. The radiopurity of the initial components employed for manufacturing crystals, that can be operated as bolometers, is crucial for achieving a null background level in the region of interest for double-beta decay investigations. In this work, we evaluated the radioactive content in 2.5 kg of 96.3 % enriched {sup 82}Se metal, measured with a high-purity germanium detector at the Gran Sasso deep underground laboratory. The limits on internal contaminations of primordial decay chain elements of {sup 232}Th, {sup 238}U and {sup 235}U are respectively: <61, <110 and <74 μBq/kg at 90 % C.L. The extremely low-background conditions in which the measurement was carried out and the high radiopurity of the {sup 82}Se allowed us to establish the most stringent lower limits on the half-lives of the double-beta decay of {sup 82}Se to 0{sub 1}{sup +}, 2{sub 2}{sup +} and 2{sub 1}{sup +} excited states of {sup 82}Kr of 3.4.10{sup 22}, 1.3.10{sup 22} and 1.0.10{sup 22} y, respectively, with a 90 % C.L. (orig.)

  7. Double-beta decay investigation with highly pure enriched ^{82}Se for the LUCIFER experiment

    Science.gov (United States)

    Beeman, J. W.; Bellini, F.; Benetti, P.; Cardani, L.; Casali, N.; Chiesa, D.; Clemenza, M.; Dafinei, I.; Domizio, S. Di; Ferroni, F.; Gironi, L.; Giuliani, A.; Gotti, C.; Laubenstein, M.; Maino, M.; Nagorny, S.; Nisi, S.; Nones, C.; Orio, F.; Pagnanini, L.; Pattavina, L.; Pessina, G.; Piperno, G.; Pirro, S.; Previtali, E.; Rusconi, C.; Schäffner, K.; Tomei, C.; Vignati, M.

    2015-12-01

    The LUCIFER project aims at deploying the first array of enriched scintillating bolometers for the investigation of neutrinoless double-beta decay of ^{82}Se. The matrix which embeds the source is an array of ZnSe crystals, where enriched ^{82}Se is used as decay isotope. The radiopurity of the initial components employed for manufacturing crystals, that can be operated as bolometers, is crucial for achieving a null background level in the region of interest for double-beta decay investigations. In this work, we evaluated the radioactive content in 2.5 kg of 96.3 % enriched ^{82}Se metal, measured with a high-purity germanium detector at the Gran Sasso deep underground laboratory. The limits on internal contaminations of primordial decay chain elements of ^{232}Th, ^{238}U and ^{235}U are respectively: <61, <110 and <74 μ Bq/kg at 90 % C.L. The extremely low-background conditions in which the measurement was carried out and the high radiopurity of the ^{82}Se allowed us to establish the most stringent lower limits on the half-lives of the double-beta decay of ^{82}Se to 0^+_1, 2^+_2 and 2^+_1 excited states of ^{82}Kr of 3.4\\cdot 10^{22}, 1.3\\cdot 10^{22} and 1.0\\cdot 10^{22} y, respectively, with a 90 % C.L.

  8. Double-beta decay investigation with highly pure enriched 82Se for the LUCIFER experiment

    International Nuclear Information System (INIS)

    The LUCIFER project aims at deploying the first array of enriched scintillating bolometers for the investigation of neutrinoless double-beta decay of 82Se. The matrix which embeds the source is an array of ZnSe crystals, where enriched 82Se is used as decay isotope. The radiopurity of the initial components employed for manufacturing crystals, that can be operated as bolometers, is crucial for achieving a null background level in the region of interest for double-beta decay investigations. In this work, we evaluated the radioactive content in 2.5 kg of 96.3 % enriched 82Se metal, measured with a high-purity germanium detector at the Gran Sasso deep underground laboratory. The limits on internal contaminations of primordial decay chain elements of 232Th, 238U and 235U are respectively: <61, <110 and <74 μBq/kg at 90 % C.L. The extremely low-background conditions in which the measurement was carried out and the high radiopurity of the 82Se allowed us to establish the most stringent lower limits on the half-lives of the double-beta decay of 82Se to 01+, 22+ and 21+ excited states of 82Kr of 3.4.1022, 1.3.1022 and 1.0.1022 y, respectively, with a 90 % C.L. (orig.)

  9. Double-beta decay investigation with highly pure enriched {sup 82}Se for the LUCIFER experiment

    Energy Technology Data Exchange (ETDEWEB)

    Beeman, J. W. [Lawrence Berkeley National Laboratory, 94720, Berkeley, CA (United States); Bellini, F. [Dipartimento di Fisica, Sapienza Università di Roma, 00185, Rome (Italy); INFN, Sezione di Roma, 00185, Rome (Italy); Benetti, P. [Dipartimento di Chimica, Università di Pavia, 27100, Pavia (Italy); INFN, Sezione di Pavia, 27100, Pavia (Italy); Cardani, L. [Dipartimento di Fisica, Sapienza Università di Roma, 00185, Rome (Italy); Physics Department, Princeton University, 08544, Princeton, NJ (United States); Casali, N. [Dipartimento di Fisica, Sapienza Università di Roma, 00185, Rome (Italy); INFN, Sezione di Roma, 00185, Rome (Italy)

    2015-12-13

    The LUCIFER project aims at deploying the first array of enriched scintillating bolometers for the investigation of neutrinoless double-beta decay of {sup 82}Se. The matrix which embeds the source is an array of ZnSe crystals, where enriched {sup 82}Se is used as decay isotope. The radiopurity of the initial components employed for manufacturing crystals, that can be operated as bolometers, is crucial for achieving a null background level in the region of interest for double-beta decay investigations. In this work, we evaluated the radioactive content in 2.5 kg of 96.3 % enriched {sup 82}Se metal, measured with a high-purity germanium detector at the Gran Sasso deep underground laboratory. The limits on internal contaminations of primordial decay chain elements of {sup 232}Th, {sup 238}U and {sup 235}U are respectively: <61, <110 and <74 μBq/kg at 90 % C.L. The extremely low-background conditions in which the measurement was carried out and the high radiopurity of the {sup 82}Se allowed us to establish the most stringent lower limits on the half-lives of the double-beta decay of {sup 82}Se to 0{sub 1}{sup +}, 2{sub 2}{sup +} and 2{sub 1}{sup +} excited states of {sup 82}Kr of 3.4·10{sup 22}, 1.3·10{sup 22} and 1.0·10{sup 22} y, respectively, with a 90 % C.L.

  10. Double-beta decay investigation with highly pure enriched 82Se for the LUCIFER experiment

    International Nuclear Information System (INIS)

    The LUCIFER project aims at deploying the first array of enriched scintillating bolometers for the investigation of neutrinoless double-beta decay of 82Se. The matrix which embeds the source is an array of ZnSe crystals, where enriched 82Se is used as decay isotope. The radiopurity of the initial components employed for manufacturing crystals, that can be operated as bolometers, is crucial for achieving a null background level in the region of interest for double-beta decay investigations. In this work, we evaluated the radioactive content in 2.5 kg of 96.3 % enriched 82Se metal, measured with a high-purity germanium detector at the Gran Sasso deep underground laboratory. The limits on internal contaminations of primordial decay chain elements of 232Th, 238U and 235U are respectively: <61, <110 and <74 μBq/kg at 90 % C.L. The extremely low-background conditions in which the measurement was carried out and the high radiopurity of the 82Se allowed us to establish the most stringent lower limits on the half-lives of the double-beta decay of 82Se to 01+, 22+ and 21+ excited states of 82Kr of 3.4·1022, 1.3·1022 and 1.0·1022 y, respectively, with a 90 % C.L

  11. Signal and background studies for the search of neutrinoless double beta decay in GERDA

    International Nuclear Information System (INIS)

    The GERDA experiment searches for the neutrinoless double beta decay in Ge-76, by operating bare HPGe detectors in ultra-pure liquid Ar. This dissertation presents a first decomposition of the background measured in the current data-taking phase. The background at the energy of interest was found to be dominated by 214Bi, 208Tl and 42K gamma-rays, with secondary contributions from 42K and 214Bi beta-rays, and 210Po alpha-rays. For the forthcoming upgrade of the apparatus, a new HPGe detector design (BEGe) has been studied, with focus on its capability of suppressing the identified backgrounds through pulse shape analysis. This included the development of a comprehensive modeling of the detectors and the experimental characterization of their response to surface interactions. The achieved results show that GERDA can improve the present limit on the neutrinoless double beta decay half-life by an order of magnitude.

  12. Theoretical half-life for beta decay of {sup 96}Zr

    Energy Technology Data Exchange (ETDEWEB)

    Heiskanen, H; Mustonen, M T; Suhonen, J [Department of Physics, University of Jyvaeskylae, PO Box 35, FIN-40351, Jyvaeskylae (Finland)

    2007-05-15

    Highly forbidden {beta}{sup -} decay of the 0{sup +} ground state of {sup 96}Zr is studied. Partial half-lives to the lowest 6{sup +}, 5{sup +} and 4{sup +} states of {sup 96}Nb have been computed using the proton-neutron quasiparticle random-phase approximation (pnQRPA) with realistic two-body interactions in a large single-particle space. We find that the decay is dominated by the unique fourth-forbidden transition to the 5{sup +} state with the half-life 2.4 x 10{sup 20} y. This half-life is an order of magnitude longer than the one measured for the double beta decay of {sup 96}Zr.

  13. Search for Neutrinoless Double-Beta Decay of $^{130}$Te with CUORE-0

    CERN Document Server

    Alfonso, K; Avignone, F T; Azzolini, O; Balata, M; Banks, T I; Bari, G; Beeman, J W; Bellini, F; Bersani, A; Biassoni, M; Brofferio, C; Bucci, C; Caminata, A; Canonica, L; Cao, X G; Capelli, S; Cappelli, L; Carbone, L; Cardani, L; Casali, N; Cassina, L; Chiesa, D; Chott, N; Clemenza, M; Copello, S; Cosmelli, C; Cremonesi, O; Creswick, R J; Cushman, J S; Dafinei, I; Dally, A; Dell'Oro, S; Deninno, M M; DiDomizio, S; DiVacri, M L; Drobizhev, A; Ejzak, L; Fang, D Q; Faverzani, M; Fernandes, G; Ferri, E; Ferroni, F; Fiorini, E; Freedman, S J; Fujikawa, B K; Giachero, A; Gironi, L; Giuliani, A; Gorla, P; Gotti, C; Gutierrez, T D; Haller, E E; Han, K; Hansen, E; Heeger, K M; Hennings-Yeomans, R; Hickerson, K P; Huang, H Z; Kadel, R; Keppel, G; Kolomensky, Yu G; Lim, K E; Liu, X; Ma, Y G; Maino, M; Martinez, M; Maruyama, R H; Mei, Y; Moggi, N; Morganti, S; Nisi, S; Nones, C; Norman, E B; Nucciotti, A; O'Donnell, T; Orio, F; Orlandi, D; Ouellet, J L; Pagliarone, C E; Pallavicini, M; Palmieri, V; Pattavina, L; Pavan, M; Pedretti, M; Pessina, G; Pettinacci, V; Piperno, G; Pirro, S; Pozzi, S; Previtali, E; Rosenfeld, C; Rusconi, C; Sala, E; Sangiorgio, S; Santone, D; Scielzo, N D; Sisti, M; Smith, A R; Taffarello, L; Tenconi, M; Terranova, F; Tomei, C; Trentalange, S; Ventura, G; Vignati, M; Wagaarachchi, S L; Wang, B S; Wang, H W; Wielgus, L; Wilson, J; Winslow, L A; Wise, T; Zanotti, L; Zarra, C; Zhang, G Q; Zhu, B X; Zucchelli, S

    2015-01-01

    We report the results of a search for neutrinoless double-beta decay in a 9.8~kg$\\cdot$yr exposure of $^{130}$Te using a bolometric detector array, CUORE-0. The characteristic detector energy resolution and background level in the region of interest are $5.1\\pm 0.3{\\rm~keV}$ FWHM and $0.058 \\pm 0.004\\,(\\mathrm{stat.})\\pm 0.002\\,(\\mathrm{syst.})$~counts/(keV$\\cdot$kg$\\cdot$yr), respectively. The median 90%~C.L. lower-limit sensitivity of the experiment is $2.9\\times 10^{24}~{\\rm yr}$ and surpasses the sensitivity of previous searches. We find no evidence for neutrinoless double-beta decay of $^{130}$Te and place a Bayesian lower bound on the decay half-life, $T^{0\

  14. Particle-vibration coupling effect on the $\\beta$-decay of magic nuclei

    CERN Document Server

    Niu, Yifei; Colo, Gianluca; Vigezzi, Enrico

    2015-01-01

    Nuclear $\\beta$-decay in magic nuclei is investigated, taking into account the coupling between particle and collective vibrations,on top of self-consistent random phase approximation calculations based on Skyrme density functionals. The low-lying Gamow-Teller strength is shifted downwards and at times becomes fragmented; as a consequence, the $\\beta$-decay half-lives are reduced due to the increase of the phase space available for the decay. In some cases, this leads to a very good agreement between theoretical and experimental lifetimes: this happens, in particular, in the case of the Skyrme force SkM*, that can also reproduce the line shape of the high energy Gamow-Teller resonance as it was previously shown.

  15. The influence of pairing on the nuclear matrix elements of the neutrinoless double beta decays

    CERN Document Server

    Caurier, E; Nowacki, F; Poves, A

    2007-01-01

    We study in this letter the behavior of the neutrinoless double beta decay nuclear matrix elements (NME's) in the framework of the Interacting Shell Model. We analize them in terms of the total angular momentum of the decaying neutron pair and as a function of the seniority truncations in the nuclear wave functions. This point of view turns out to be very adequate to gauge the accuracy of the NME's predicted by different nuclear structure models. In addition, it gives back the due protagonism in this process to the pairing interaction, the interaction which is responsible for the very existence of double beta decay emitters. We show that low seniority approximations, such as the quasiparticle RPA in an spherical basis, tend to overestimate the values of the NME's.

  16. Latest results of NEXT-DEMO, the prototype of the NEXT 100 double beta decay experiment

    CERN Document Server

    Serra, L; Martin-Albo, J; Sorel, M; Gomez-Cadenas, J J

    2014-01-01

    NEXT-DEMO is a 1:4.5 scale prototype of the NEXT100 detector, a high-pressure xenon gas TPC that will search for the neutrinoless double beta decay of $^{136}$Xe. X-ray energy depositions produced by the de-excitation of Xenon atoms after the interaction of gamma rays from radioactive sources have been used to characterize the response of the detector obtaining the spatial calibration needed for close-to-optimal energy resolution. Our result, 5.5% FWHM at 30 keV, extrapolates to 0.6% FWHM at the Q value of $^{136}$Xe. Additionally, alpha decays from radon have been used to measure several detection properties and parameters of xenon gas such as electron-ion recombination, electron drift velocity, diffusion and primary scintillation light yield. Alpha spectroscopy is also used to quantify the activity of radon inside the detector, a potential source of background for most double beta decay experiments.

  17. Electromagnetically induced nuclear beta decay calculated by a Green's function method

    International Nuclear Information System (INIS)

    The transition probability for enhancement of forbidden nuclear beta decay by an applied plane-wave electromagnetic field is calculated in a nonrelativistic spinless approximation by a Green's function method. The calculation involves a stationary-phase approximation. The stationary phase points in the presence of an intense field are located in very different positions than they are in the field-free case. In order-of-magnitude terms, the results are completely consistent with an earlier, much more complete wave-function calculation which includes spin and relativistic effects. Both the present Green's function calculation and the earlier wave function calculation give electromagnetic contributions in first-forbidden nuclear beta decay matrix elements which are of order (R0/lambda-dash-bar/sub C/)2 with respect to allowed decays, where R0 is the nuclear radius and lambda-dash-bar/sub C/ is the electron Compton wavelength

  18. Experiments TGV I (double-beta decay of 48Ca) and TGV II (double-beta decay of 106Cd and 48Ca)

    International Nuclear Information System (INIS)

    Present status of experiments TGV I and TGV II is given. The TGV I collaboration has studied the double-beta decay of 48Ca with a low-background and high sensitivity Ge multi-detector spectrometer TGV (Telescope Germanium Vertical). The preliminary results of T1/22νββ = (4.2 (+3.3) (-1.3)) x 1019 years and T1/20νββ > 1.5 x 1021 years (90% CL) for double-beta decay of 48Ca has been found after the processing of experimental data obtained after 8700 hours of measuring time using approximately 1 gram of 48Ca. The aim of the experiment TGV II is the development of the experimental methods, construction of spectrometers and measurement of the ββ decay (β+β+, β+ /EC, EC/EC) of 106Cd particularly the 2νEC/EC mode. The theoretical description and performance of the TGV II spectrometer are also given. (author)

  19. $\\beta$-delayed $\\gamma$-proton decay in $^{56}$Zn: analysis of the charged-particle spectrum

    CERN Document Server

    Orrigo, S E A; Fujita, Y; Blank, B; Gelletly, W; Agramunt, J; Algora, A; Ascher, P; Bilgier, B; Cáceres, L; Cakirli, R B; Fujita, H; Ganioglu, E; Gerbaux, M; Giovinazzo, J; Grévy, S; Kamalou, O; Kozer, H C; Kucuk, L; Kurtukian-Nieto, T; Molina, F; Popescu, L; Rogers, A M; Susoy, G; Stodel, C; Suzuki, T; Tamii, A; Thomas, J C

    2015-01-01

    A study of the $\\beta$ decay of the proton-rich $T_{z}$ = -2 nucleus $^{56}$Zn has been reported in a recent publication. A rare and exotic decay mode, $\\beta$-delayed $\\gamma$-proton decay, has been observed there for the first time in the $fp$ shell. Here we expand on some of the details of the data analysis, focussing on the charged particle spectrum.

  20. Measurement of the CP violating phase beta_s in B_s->J/psi phi decays

    Energy Technology Data Exchange (ETDEWEB)

    Oakes, Louise Beth; /Oxford U.

    2010-07-01

    The CP violating phase {beta}{sub s}{sup J/{psi}{phi}} is measured in decays of B{sub s}{sup 0} {yields} J/{psi}{phi}. This measurement uses 5.2 fb{sup -1} of data collected in {radical}s = 1.96 TeV p{bar p} collisions at the Fermilab Tevatron with the CDF Run-II detector. CP violation in the B{sub s}{sup 0}-{bar B}{sub s}{sup 0} system is predicted to be very small in the Standard Model. However, several theories beyond the Standard Model allow enhancements to this quantity by heavier, New Physics particles entering second order weak mixing box diagrams. Previous measurements have hinted at a deviation from the Standard Model expectation value for {beta}{sub s}{sup J/{psi}{phi}} with a significance of approximately 2{sigma}. The measurement described in this thesis uses the highest statistics sample available to date in the B{sub s}{sup 0} {yields} J/{psi}{phi} decay channel, where J/{psi} {yields} {mu}{sup +}{mu}{sup -} and {phi} {yields} K{sup +}K{sup -}. Furthermore, it contains several improvements over previous analyses, such as enhanced signal selection, fully calibrated particle ID and flavour tagging, and the inclusion of an additional decay component in the likelihood function. The added decay component considers S-wave states of KK pairs in the B{sub s}{sup 0} {yields} J/{psi} K{sup +}K{sup -} channel. The results are presented as 2-dimensional frequentist confidence regions for {beta}{sub s}{sup J/{psi}{phi}} and {Delta}{Lambda} (the width difference between the B{sub s}{sup 0} mass eigenstates), and as a confidence interval for {beta}{sub s}{sup J/{psi}{phi}} of [0.02,0.52] {union} [1.08, 1.55] at the 68% confidence level. The measurement of the CP violating phase obtained in this thesis is complemented by the world's most precise measurement of the lifetime {tau}{sub s} = 1.53 {+-} 0.025 (stat.) {+-} 0.012 (syst.) ps and decay width difference {Delta}{Lambda} = 0.075 {+-} 0.035 (stat.) {+-} 0.01 (syst.) ps{sup -1} of the B{sub s}{sup 0} meson

  1. Status of the Los Alamos tritium beta decay experiment

    International Nuclear Information System (INIS)

    The Los Alamos tritium experiment employs a gaseous tritium source and a magnetic spectrometer to determine the mass of the electron antineutrino from the shape of the tritium beta spectrum. Since publication of the first result from this apparatus (m/sub nu/ < 27 eV at 95% confidence), work has concentrated on improving the data rates. A 96-element Si microstrip array detector has been installed to replace the single proportional counter at the spectrometer focus, resulting in greatly increased efficiency. Measurements of the 1s photoionization spectrum of Kr now obviate the need for reliance on the theoretical shakeup and shakeoff spectrum of Kr in determining the spectrometer resolution. 19 refs., 3 figs

  2. Searching for the Dirac Nature of Neutrinos: Combining Neutrinoless Double Beta Decay and Neutrino Mass Measurements

    International Nuclear Information System (INIS)

    We studied the neutrinoless double beta decay process to tackle the issue about the nature of neutrino. Establishing the nature of neutrinos, whether they are Dirac or Majorana particles is one of the fundamental questions we need to answer in particle physics, and is related to the conservation of lepton number. Neutrinoless double beta decay ((ββ)0ν) is the tool of choice for testing the Majorana nature of neutrinos. However, up to now, this process has not been observed, but a wide experimental effort is taking place worldwide and soon new results will become available. Different mechanisms can induce (ββ)0ν-decay and might interfere with each other, potentially leading to suppressed contributions to the decay rate. This possibility would become of great interest if upcoming neutrino mass measurements from KATRIN and cosmological observations found that mν>0.2eV but no positive signal was observed in (ββ)0ν-decay experiments. We focus on the possible interference between light Majorana neutrino exchange with other mechanisms, such as heavy sterile neutrinos and R-parity violating supersymmetric models. We show that in some cases the use of different nuclei would allow to disentangle the different contributions and allow to test the hypothesis of destructive interference. Finally, we present a model in which such interference can emerge and we discuss the range of parameters which would lead to a significant suppression of the decay rate

  3. Effective Majorana mass and neutrinoless double beta decay

    Energy Technology Data Exchange (ETDEWEB)

    Benato, Giovanni, E-mail: gbenato@physik.uzh.ch [Physik Institut der Universität Zürich, Zurich (Switzerland)

    2015-11-28

    The probability distribution for the effective Majorana mass as a function of the lightest neutrino mass in the standard three neutrino scheme is computed via a random sampling from the distributions of the involved mixing angles and squared mass differences. A flat distribution in the [0,2π] range for the Majorana phases is assumed, and the dependence of small values of the effective mass on the Majorana phases is highlighted. The study is then extended with the addition of the cosmological bound on the sum of the neutrino masses. Finally, the prospects for 0νββ decay search with {sup 76}Ge, {sup 130}Te and {sup 136}Xe are discussed, as well as those for the measurement of the electron neutrino mass.

  4. Beta asymmetries in the decay of polarized 56Co

    International Nuclear Information System (INIS)

    Allowed isospin-hindered positron decay from polarized 56Co has been studied using a β-particle detection assembly mounted on a 3He/4He dilution refrigerator, and the asymmetry parameter was found to be A/sub β/ = +0.359 +- 0.009. Assuming the standard V-A weak interaction theory and time-reversal invariance, the Fermi to Gamow-Teller interference ratio, y = C/sub V/M/sub F//C/sub A/M/sub GT/, is then -0.091 +- 0.005. Our high precision result is in reasonable agreement with most of the previously reported results, but is in serious disagreement with an earlier measurement by Pingot, who found y = +0.002 +- 0.004

  5. Kinematic sensitivity to the Fierz term of $\\beta$-decay differential spectra

    CERN Document Server

    Gonzalez-Alonso, Martin

    2016-01-01

    The current most stringent constraints on exotic scalar or tensor couplings in neutron and nuclear $\\beta$ decay, involving left-handed neutrinos, are obtained from the Fierz interference term. The sensitivity to this term in a correlation coefficient is usually driven by an energy-averaged kinematic factor that increases monotonically toward smaller values of the $\\beta$ endpoint energies. We first point out here that this property does not hold for certain differential observables that are directly sensitive to the Fierz term, such as the $\\beta$ or the recoil energy spectrum. This observation is relevant for the selection of sensitive transitions in searches for exotic couplings through spectrum shape measurements. We then point out previous errors in the exploitation of measurements of the $\\beta-\

  6. Nuclear matrix elements of neutrinoless double beta decay with improved short-range correlations

    CERN Document Server

    Kortelainen, Markus

    2007-01-01

    Nuclear matrix elements of the neutrinoless double beta decays of 96Zr, 100Mo, 116Cd, 128Te, 130Te and 136Xe are calculated for the light-neutrino exchange mechanism by using the proton-neutron quasiparticle random-phase approximation (pnQRPA) with a realistic nucleon-nucleon force. The g_pp parameter of the pnQRPA is fixed by the data on the two-neutrino double beta decays and single beta decays. The finite size of a nucleon, the higher-order terms of nucleonic weak currents, and the nucleon-nucleon short-range correlations (s.r.c) are taken into account. The s.r.c. are computed by the traditional Jastrow method and by the more advanced unitary correlation operator method (UCOM). Comparison of the results obtained by the two methods is carried out. The UCOM computed matrix elements turn out to be considerably larger than the Jastrow computed ones. This result is important for the assessment of the neutrino-mass sensitivity of the present and future double beta experiments.

  7. First direct determination of the superallowed $\\beta$-decay $Q_{EC}$-value for $^{14}$O

    CERN Document Server

    Valverde, A A; Brodeur, M; Bryce, R A; Cooper, K; Eibach, M; Gulyuz, K; Izzo, C; Morrissey, D J; Redshaw, M; Ringle, R; Sandler, R; Schwarz, S; Sumithrarachchi, C S; Villari, A C C

    2015-01-01

    We report the first direct measurement of the $^{14}\\text{O}$ superallowed Fermi $\\beta$-decay $Q_{EC}$-value, the last of the so-called "traditional nine" superallowed Fermi $\\beta$-decays to be measured with Penning trap mass spectrometry. $^{14}$O, along with the other low-$Z$ superallowed $\\beta$-emitter, $^{10}$C, is crucial for setting limits on the existence of possible scalar currents. The new ground state $Q_{EC}$ value, 5144.364(25) keV, when combined with the energy of the $0^+$ daughter state, $E_x(0^+)=2312.798(11)$~keV [Nucl. Phys. A {\\bf{523}}, 1 (1991)], provides a new determination of the superallowed $\\beta$-decay $Q_{EC}$ value, $Q_{EC}(\\text{sa}) = 2831.566(28)$ keV, with an order of magnitude improvement in precision, and a similar improvement to the calculated statistical rate function $f$. This is used to calculate an improved $\\mathcal{F}t$-value of 3073.8(2.8) s.

  8. Purification of lanthanides for double beta decay experiments

    Science.gov (United States)

    Polischuk, O. G.; Barabash, A. S.; Belli, P.; Bernabei, R.; Boiko, R. S.; Cappella, F.; Cerulli, R.; Danevich, F. A.; Incicchitti, A.; Laubenstein, M.; Mokina, V. M.; Nisi, S.; Poda, D. V.; Tretyak, V. I.

    2013-08-01

    There are several potentially double beta active isotopes among the lanthanide elements. However, even high purity grade lanthanide compounds contain 238U, 226Ra and 232,228Th typically on the level of ˜ (0.1 - 1) Bq/kg. The liquid-liquid extraction technique was used to remove traces of U, Ra and Th from CeO2, Nd2O3 and Gd2O3. The radioactive contamination of the samples before and after the purification was tested by using ultra-low-background HPGe γ spectrometry at the underground Gran Sasso National Laboratories of the INFN (Italy). After the purification the radioactive contamination of gadolinium oxide by Ra and Th was decreased at least one order of magnitude. The efficiency of the approach to purify cerium oxide from Ra was on same level, while the radioactive contamination of neodymium sample before and after the purification is below the sensitivity of analytical methods. The purification method is much less efficient for chemically very similar radioactive elements like lanthanum, lutetium and actinium. R&D of the methods to remove the pollutions with improved efficiency is in progress.

  9. Purification of lanthanides for double beta decay experiments

    Energy Technology Data Exchange (ETDEWEB)

    Polischuk, O. G. [Institute for Nuclear Research, MSP 03680 Kyiv, Ukraine and INFN, Section of Rome, La Sapienza, I-00185 Rome (Italy); Barabash, A. S. [Institute of Theoretical and Experimental Physics, 117259 Moscow (Russian Federation); Belli, P. [INFN, Section of Rome Tor Vergata, I-00133 Rome (Italy); Bernabei, R. [INFN, Section of Rome Tor Vergata, I-00133 Rome, Italy and Department of Physics, University of Rome Tor Vergata, I-00133 Rome (Italy); Boiko, R. S.; Danevich, F. A.; Mokina, V. M.; Poda, D. V.; Tretyak, V. I. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine); Cappella, F.; Incicchitti, A. [INFN, Section of Rome La Sapienza, I-00185 Rome, Italy and Department of Physics, University of Rome La Sapienza, I-00185 Rome (Italy); Cerulli, R.; Laubenstein, M.; Nisi, S. [INFN, Gran Sasso National Laboratories, I-67100 Assergi (Aq) (Italy)

    2013-08-08

    There are several potentially double beta active isotopes among the lanthanide elements. However, even high purity grade lanthanide compounds contain {sup 238}U, {sup 226}Ra and {sup 232,228}Th typically on the level of ∼ (0.1 - 1) Bq/kg. The liquid-liquid extraction technique was used to remove traces of U, Ra and Th from CeO{sub 2}, Nd{sub 2}O{sub 3} and Gd{sub 2}O{sub 3}. The radioactive contamination of the samples before and after the purification was tested by using ultra-low-background HPGe γ spectrometry at the underground Gran Sasso National Laboratories of the INFN (Italy). After the purification the radioactive contamination of gadolinium oxide by Ra and Th was decreased at least one order of magnitude. The efficiency of the approach to purify cerium oxide from Ra was on same level, while the radioactive contamination of neodymium sample before and after the purification is below the sensitivity of analytical methods. The purification method is much less efficient for chemically very similar radioactive elements like lanthanum, lutetium and actinium. R and D of the methods to remove the pollutions with improved efficiency is in progress.

  10. Absolute Branching Fractions of Cabibbo-Suppressed D --> K Kbar Decays

    CERN Document Server

    Bonvicini, G; Dubrovin, M; Lincoln, A; Rademacker, J; Asner, D M; Edwards, K W; Naik, P; Reed, J; Briere, R A; Ferguson, T; Tatishvili, G; Vogel, H; Watkins, M E; Rosner, J L; Alexander, J P; Cassel, D G; Duboscq, J E; Ehrlich, R; Fields, L; Gibbons, L; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Mahlke-Krüger, H; Mohapatra, D; Miyake, H; Onyisi, P U E; Patterson, J R; Peterson, D; Riley, D; Ryd, A; Sadoff, A J; Shi, X; Stroiney, S; Sun, W M; Wilksen, T; Athar, S B; Patel, R; Yelton, J; Rubin, P; Eisenstein, B I; Karliner, I; Mehrabyan, S; Lowrey, N; Selen, M; White, E J; Wiss, J; Mitchell, R E; Shepherd, M R; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Poling, R; Scott, A W; Zweber, P; Dobbs, S; Metreveli, Z; Seth, K K; Tomaradze, A G; Libby, J; Powell, A; Wilkinson, G; Ecklund, K M; Love, W; Savinov, V; López, A; Méndez, H; Ramírez, J; Ge, J Y; Miller, D H; Shipsey, I P J; Xin, B; Adams, G S; Anderson, M; Cummings, J P; Danko, I; Hu, D; Moziak, B; Napolitano, J; He, Q; Insler, J; Muramatsu, H; Park, C S; Thorndike, E H; Yang, F; Artuso, M; Blusk, S; Khalil, S; Li, J; Mountain, R; Nisar, S; Randrianarivony, K; Sultana, N; Skwarnicki, T; Stone, S; Wang, J C; Zhang, L M

    2008-01-01

    Using 281/pb of data collected with the CLEO-c detector at the psi(3770) resonance, we have studied Cabibbo-suppressed decays of D mesons to final states with two kaons. We present results for the absolute branching fractions of the modes D^0 --> K^+ K^-, D^0 --> K^0_S K^0_S, and D^+ --> K^+ K^0_S. We measure B(D^0 --> K^+ K^-) = (4.08 +- 0.08 +- 0.09) x 10^-3, B(D^0 --> K^0_S K^0_S) = (1.46 +- 0.32 +- 0.09) x 10^-4, and B(D^+ --> K^+ K^0_S) = (3.14 +- 0.09 +- 0.08) x 10^-3. We also determine the ratio B(D^0 --> K^+ K^-)/B(D^0 --> pi^+ pi^-) = 2.89 +- 0.05 +- 0.06. For each measurement, the first uncertainty is statistical and the second uncertainty is systematic.

  11. Study of octupole deformation in n-rich Ba isotopes populated via $\\beta$-decay

    CERN Multimedia

    We propose to exploit the unique capability of the ISOLDE facility to produce $^{150−151−152}$Cs beams to investigate their radioactive $\\beta$-decay to $^{150−151−152}$Ba. The interest to study this mass region is twofold: from one side these nuclei are expected to show octupole deformations already in their low-lying state, and, on the other hand, gross information on the $\\beta$-decay is highly demanded for nuclear astrophysical model, given the fact that the r-process path lies in the proximity of 1 accessible nuclei. The experiment will be performed with the ISOLDE Decay Station (IDS) setup using the fast tape station of K.U.-Leuven, equipped with 4 Clover Germanium detectors, 4 LaBr$_{3}$(Ce) detectors and 1 LEP HPGe detector. Information on the $\\beta$-decay, such as lifetimes and delayed neutron-emission probabilities, will be extracted, together with the detailed spectroscopy of the daughter nuclei, via $\\gamma-\\gamma$-coincidences and lifetimes measurement of specific states.

  12. Radiative Corrections to the Neutron Beta-decay within the Standard Model

    CERN Document Server

    Bunatian, G G

    2003-01-01

    Starting with the basic Lagrangian of the Standard Model, the radiative corrections to the neutron beta-decay are acquired. The electroweak interactions are consistently taken into consideration amenably to the Weinberg-Salam theory. The effect of the strong quark-quark interactions on the neutron beta-decay is parameterized by introducing the nucleon electromagnetic form factors and the nucleon weak transition current specified by the form factors g_V, g_A, ... The radiative corrections to the total decay probability W and to the asymmetry coefficient of the electron momentum distribution A obtained to constitute \\delta W = 8.7%, \\delta A = -2% . The contribution to the radiative corrections due to allowance for the nucleon form factors and the nucleon exited states amounts up to a few per cent to the whole value of the radiative corrections. The ambiguity in description of the nucleon compositeness is this surely what causes the uncertainties ~0.1% in evaluation of the neutron beta-decay characteristics. Fo...

  13. Neutrinoless double beta decay. Electron angular correlation as a probe of new physics

    International Nuclear Information System (INIS)

    The angular distribution of the final electrons in the so-called long range mechanism of the neutrinoless double beta decay (0ν2β) is derived for the general Lorentz invariant effective Lagrangian. Possible theories beyond the SM are classified from their effects on the angular distribution, which could be used to discriminate among various particle physics models inducing 0ν2β decays. However, additional input on the effective couplings will be required to single out the light Majorana-neutrino mechanism. Alternatively, measurements of the effective neutrino mass and angular distribution in 0ν2β decays can be used to put independent bounds on the parameters of the underlying physics models. This is illustrated for the mass of the right-handed WR boson of the left-right symmetric model for assumed values of the angular correlation coefficient and either the effective Majorana neutrino mass or the half-life of the decay. (Orig.)

  14. Beta Decay Half-Life of 84Mo

    Science.gov (United States)

    Stoker, J. B.; Mantica, P. F.; Bazin, D.; Bickley, A.; Becerril, A.; Crawford, H.; Cruse, K.; Estrade, A.; Mosby, M.; Guess, C. J.; Hitt, G. W.; Lorusso, G.; Matos, M.; Meharchand, R.; Minamisono, K.; Montes, F.; Pereira, J.; Perdikakis, G.; Pinter, J. S.; Schatz, H.; Vredevoogd, J.; Zegers, R. G. T.

    2008-10-01

    The β-decay half-life ^84Mo governs leakage out of the Zr-Nb cycle, a high temperature rp-process endpoint in x-ray binaries [1]. Treatment of the background and the poor statistics accumulated during the previous half-life measurement leave questions about statistical and systematic errors. We have remeasured the half-life of ^84Mo using a concerted setup of the NSCL β-Counting System [3] and 16 detectors from the Segmented Germanium Array [4]. We will report the half-life for ^84Mo, deduced using 40 times the previous sample size. The application of the NSCL RF Fragment Separator to remove unwanted isotopes, and hence reduce background for the half-life measurement, will also be discussed. [1] H. Schatz et al., Phys. Rep. 294, 167 1998 [2] P. Kienle et al., Prog. Part. Nuc. Phys. 46, 73 2001 [3] J. Prisciandaro et al., NIM A 505, 140 2003 [4] W. Mueller et al., NIM A 466, 492 2001 [5] D. Gorelov et al. PAC 2005, Knoxville, TN, May 16-20

  15. Half-lives and branchings for {\\beta}-delayed neutron emission for neutron-rich Co-Cu isotopes in the r-process

    CERN Document Server

    Hosmer, P; Aprahamian, A; Arndt, O; Clement, R R C; Estrade, A; Farouqi, K; Kratz, K -L; Liddick, S N; Lisetskiy, A F; Mantica, P F; Möller, P; Mueller, W F; Montes, F; Morton, A C; Ouellette, M; Pellegrini, E; Pereira, J; Pfeiffer, B; Reeder, P; Santi, P; Steiner, M; Stolz, A; Tomlin, B E; Walters, W B; Wöhr, A; 10.1103/PhysRevC.82.025806

    2010-01-01

    The {\\beta} decays of very neutron-rich nuclides in the Co-Zn region were studied experimentally at the National Superconducting Cyclotron Laboratory using the NSCL {\\beta}-counting station in conjunction with the neutron detector NERO. We measured the branchings for {\\beta}-delayed neutron emission (Pn values) for 74Co (18 +/- 15%) and 75-77Ni (10 +/- 2.8%, 14 +/- 3.6%, and 30 +/- 24%, respectively) for the first time, and remeasured the Pn values of 77-79Cu, 79,81Zn, and 82Ga. For 77-79Cu and for 81Zn we obtain significantly larger Pn values compared to previous work. While the new half-lives for the Ni isotopes from this experiment had been reported before, we present here in addition the first half-life measurements of 75Co (30 +/- 11 ms) and 80Cu (170+110 -50 ms). Our results are compared with theoretical predictions, and their impact on various types of models for the astrophysical rapid neutron-capture process (r-process) is explored. We find that with our new data, the classical r-process model is bet...

  16. Superallowed beta decays, Vud and CKM matrix: the case of 38Km

    International Nuclear Information System (INIS)

    Full text: As part of a program to improve the experimental data base of positron decay Q-values and lifetimes from which Ft values are calculated, we have studied the decay of 38Km to 38Ar. Our recent measurement of the decay energy as 6044.34(12)keV is consistent with, but improves upon, the accepted value. The data base for the half-life of 38Km is however, much less satisfactory, with a Chi-square of 27 for five measurements. Accordingly, we have made a careful study of this problem, concentrating on an exploration of possible systematic effects due to low-level contaminant activities, the unavoidable presence of the decay of the 38K ground state, and the various side-effects of excessive count rates. As a result, we believe the problem to be now resolved. We will recommend a half-life for 38Km, and also a new, higher precision, Ft value. The assumption of the validity of the Conserved Vector Current Theory for the nine precisely determined Ft values of 0+ → 0+, T=1 superallowed beta decays, of which 38Km (β+)38Ar is an example, provides a high precision test of the unitarity of the first row of the CKM matrix. At the moment the test seems to fail at the few-sigma level on the low side when the value of Vud is derived from these beta decays, which would seem to indicate a possibility for new physics. However, if Vud is derived from Ft and asymmetry measurements for the decay of cold neutrons, the test is failed by roughly the same amount on the high side. Interestingly, the latest measurement of the neutron decay asymmetry coefficient, if not averaged with other earlier values would place the unitarity test at the same value as the that from the positron Ft values. We will briefly discuss this situation

  17. Exploring the Neutrinoless Double Beta Decay in the Inverted Neutrino Hierarchy with Bolometric Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Artusa, D. R.; Azzolini, O.; Balata, M.; Banks, T. I.; Bari, G.; Beeman, J.; Bellini, F.; Bersani, A.; Biassoni, M.; Brofferio, C.; Bucci, C.; Cai, X. Z.; Camacho, A.; Canonica, L.; Cao, X. G.; Capelli, S.; Carbone, L.; Cardani, L.; Carrettoni, M.; Casali, N.; Chiesa, D.; Chott, N.; Clemenza, M.; Cosmelli, C.; Cremonesi, O.; Creswick, R. J.; Dafinei, I.; Dally, A.; Datskov, V.; Biasi, A. De; Deninno, M. M.; Domizio, S. Di; Vacri, M. L. di; Ejzak, L.; Fang, D. Q.; Farach, H. A.; Faverzani, M.; Fernandes, G.; Ferri, E.; Ferroni, F.; Fiorini, E.; Franceschi, M. A.; Freedman, S. J.; Fujikawa, B. K.; Giachero, A.; Gironi, L.; Giuliani, A.; Goett, J.; Gorla, P.; Gotti, C.; Gutierrez, T. D.; Haller, E. E.; Han, K.; Heeger, K. M.; Hennings-Yeomans, R.; Huang, H. Z.; Kadel, R.; Kazkaz, K.; Keppel, G.; Kolomensky, Yu. G.; Li, Y. L.; Ligi, C.; Liu, X.; Ma, Y. G.; Maiano, C.; Maino, M.; Martinez, M.; Maruyama, R. H.; Mei, Y.; Moggi, N.; Morganti, S.; Napolitano, T.; Nisi, S.; Norman, E. B.; Nucciotti, A.; O' Donnell, T.; Orio, F.; Orlandi, D.; Ouellet, J. L.; Pallavicini, M.; Palmieri, V.; Pattavina, L.; Pavan, M.; Pedretti, M.; Pessina, G.; Pettinacci, V.; Piperno, G.; Pira, C.; Pirro, S.; Previtali, E.; Rampazzo, V.; Rosenfeld, C.; Rusconi, C.; Sala, E.; Sangiorgio, S.; Scielzo, N. D.; Sisti, M.; Smith, A. R.; Taffarello, L.; Tenconi, M.; Terranova, F.; Tian, W. D.; Tomei, C.; Trentalange, S.; Ventura, G.; Vignati, M.; Wang, B. S.; Wang, H. W.; Wielgus, L.; Wilson, J.; Winslow, L. A.; Wise, T.; Woodcraft, A.; Zanotti, L.; Zarra, C.; Zhu, B. X.

    2014-10-15

    Neutrinoless double beta decay (0nubb) is one of the most sensitive probes for physics beyond the Standard Model, providing unique information on the nature of neutrinos. In this paper we review the status and outlook for bolometric 0{nu}{beta}{beta} decay searches. We summarize recent advances in background suppression demonstrated using bolometers with simultaneous readout of heat and light signals. We simulate several configurations of a future CUORE-like bolometer array which would utilize these improvements and present the sensitivity reach of a hypothetical next-generation bolometric 0{nu}{beta}{beta} experiment. We demonstrate that a bolometric experiment with the isotope mass of about 1 ton is capable of reaching the sensitivity to the effective Majorana neutrino mass (|m{sub ee}|) of order 10-20 meV, thus completely exploring the so-called inverted neutrino mass hierarchy region. We highlight the main challenges and identify priorities for an R&D program addressing them.

  18. P-426 measurement of the $\\beta$-asymmetry parameter in $^{35}$Ar decay with a laser polarized beam.

    CERN Multimedia

    With this proposal we request beam time for the first two phases of a project that aims at measuring the $\\beta$-asymmetry parameter of the mirror $\\beta$-decay branch in $^{35}$Ar using an optically polarized Ar atom beam. The final goal of the experiment is to measure this parameter to a precision of 0.5%. This will allow the most precise determination of the V$_{ud}$ quark mixing matrix element from all the mirror transitions with an absolute uncertainty of 0.0007. The proposal will be presented in phases and we ask here 11 shifts (7 on-line + 4 off-line) for phase 1 and 15 shifts (6 on-line and 9 off-line) for phase 2. Phase 1 aims at establishing the optimal laser polarization scheme as well as the best implantation host for maintaining the polarization. Phase 2 aims at enhancing the beam polarization by removing the unpolarized part of the beam using re-ionization.

  19. Beta decay and delayed proton emission of a new nuclide 59Zn

    International Nuclear Information System (INIS)

    The β+-decay of a new nuclide 59Zn has been identified by β-delayed proton and γ-ray emission. Two γ-rays and 15 proton groups have been associated with the decay of 59Zn. The total proton branching ratio was measured to be (2.3 +- 0.8) x 10-4. A half-life of 210 +- 20 ms was measured for 59Zn. The superallowed β-branch to its mirror, the Jsup(π)=3/2- ground state of 59Cu, was shown to be (93 +- 3)%. Absolute log ft values for β-transitions associated with the observed delayed proton groups were calculated and an experimental β-transition strength function was obtained. (author)

  20. Study of multi-neutron emission in the $\\beta$-decay of $^{11}$Li

    CERN Multimedia

    A new investigation of neutron emission in the $\\beta$-decay of $^{11}$Li is proposed. The principal goal of this study will be to directly measure, for the first time for any system, two $\\beta$-delayed neutrons in coincidence and determine the energy and angular correlations. This will be possible using liquid scintillator detectors, capable of distinguishing between neutrons and ambient $\\gamma$ and cosmic-rays, coupled to a new digital electronics and acquisition system. In parallel, a considerably more refined picture of the single-neutron emission will be obtained.