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Sample records for antineutrino nucleon scattering

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

    NASA Astrophysics Data System (ADS)

    Alvarez-Ruso, L.; Nieves, J.; Wang, E.

    2015-10-01

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

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

    SciTech Connect

    Alvarez-Ruso, L.; Nieves, J.; Wang, E.

    2015-10-15

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

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

    SciTech Connect

    Rakotondravohitra, Laza

    2015-08-18

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

  4. Nucleon Compton Scattering

    SciTech Connect

    Bogdan Wojtsekhowski

    2006-06-04

    Review of Nucleon Compton Scattering in wide angle regime is presented. JLab experimental data strongly support dominance of handbag mechanism in the RCS process. The approved ALLRCS experiment with polarized target and future plans with 12 GeV beam are discussed.

  5. Polarized lepton-nucleon scattering

    SciTech Connect

    Hughes, E.

    1994-02-01

    Deep inelastic polarized lepton-nucleon scattering is reviewed in three lectures. The first lecture covers the polarized deep inelastic scattering formalism and foundational theoretical work. The second lecture describes the nucleon spin structure function experiments that have been performed up through 1993. The third lecture discusses implication of the results and future experiments aimed at high-precision measurements of the nucleon spin structure functions.

  6. The scattering of fast nucleons from nuclei

    SciTech Connect

    Kerman, A. K.; McManus, H.; Thaler, R. M.

    2000-04-10

    The formal theory of the scattering of high-energy nucleons by nuclei is developed in terms of the nucleon nucleon scattering amplitude. The most important approximations necessary to make numerical calculation feasible are then examined. The optical model potential is derived on this basis and compared with the optical model parameters found from experiment. The elastic scattering and polarization of nucleons from light nuclei is predicted and compared with experiment. The effect of nuclear correlations is discussed. The polarization of inelastically scattered nucleons is discussed and predictions compared with experiments. To within the validity of the approximations the experimental data on the scattering of nucleons from nuclei at energies above {approx}100 Mev appears to be consistent with the theory. (c) 2000 Academic Press, Inc.

  7. Neutrino-pair bremsstrahlung from nucleon-nucleon scattering

    SciTech Connect

    Li, Yi; Liou, M. K.; Schreiber, W. M.; Gibson, B. F.

    2015-07-22

    Background: Neutrino-pair bremsstrahlung processes from nucleon-nucleon scattering ΝΝνν¯ (nnvv¯, ppvv¯, and npvv¯) have recently attracted attention in studies of neutrino emission in neutron stars, because of the implications for the neutron star cooling. The calculated ΝΝνν¯ emissivities within the neutron star environment are relatively insensitive to the two-nucleon dynamical model used in the calculations, but differ significantly from those obtained using an OPE model. Purpose: To investigate the free ΝΝνν¯ cross sections using a realistic nucleon-nucleon scattering amplitude, comparing the relative sizes of the cross sections for the three processes nnvv¯, ppvv¯, and npvv¯.

  8. Backward pion-nucleon scattering

    SciTech Connect

    F. Huang; Sibirtsev, Alex; Haidenbauer, Johann; Meissner, Ulf-G.

    2010-02-01

    A global analysis of the world data on differential cross sections and polarization asymmetries of backward pion-nucleon scattering for invariant collision energies above 3 GeV is performed in a Regge model. Including the $N_\\alpha$, $N_\\gamma$, $\\Delta_\\delta$ and $\\Delta_\\beta$ trajectories, we reproduce both angular distributions and polarization data for small values of the Mandelstam variable $u$, in contrast to previous analyses. The model amplitude is used to obtain evidence for baryon resonances with mass below 3 GeV. Our analysis suggests a $G_{39}$ resonance with a mass of 2.83 GeV as member of the $\\Delta_{\\beta}$ trajectory from the corresponding Chew-Frautschi plot.

  9. Nucleon-nucleon scattering contribution to the triton binding energy

    SciTech Connect

    Noyes, H.P.

    1983-04-01

    We conjectured in 1972 that much of the dynamics of a few nucleon systems could be computed from the on-shell nucleon-nucleon scatterings provided that a consistent few body theory using this input could be constructed. Such a Zero Range Scattering Theory has been shown to lead to unitary three and four particle scattering amplitudes provided only the two particle amplitudes have no singularities other than bound state poles when continued to negative energies, which restricts the theory to Castillejo-Dalitz-Dyson solutions of the Low equation. We extend the model by rewriting the off-shell amplitude which drives the Faddeev equations. This amplitude retains full off-shell unitarity and still leads to unitary on-shell three particle amplitudes. This amounts to keeping any unitary two-nucleon amplitude on-shell and restricting the analytic continuation to negative energies to the term which represents the correct continuation of the two particle total partial wave cross section; the meson exchange or potential contributions are eliminated in the unphysical region, thus excising the left-hand cut. Using this model in the zero range Faddeev equations for the three nucleon system our preliminary results show that the on-shell scatterings bind the triton with about 2.5 MeV and are insensitive to the details of the fit.

  10. Nucleon-nucleon scattering within a multiple subtractive renormalization approach

    SciTech Connect

    Timoteo, V. S.; Frederico, T.; Delfino, A.; Tomio, Lauro

    2011-06-15

    We present a methodology to renormalize the nucleon-nucleon interaction in momentum space, using a recursive multiple subtraction approach that prescinds from a cutoff regularization, to construct the kernel of the scattering equation. The subtracted scattering equation is solved with the next-leading-order and next-to-next-leading-order interactions. The results are presented for all partial waves up to j=2, fitted to low-energy experimental data. In this renormalization group invariant approach, the subtraction energy emerges as a renormalization scale and the momentum associated with it comes to be about the QCD scale ({Lambda}{sub QCD}), irrespectively to the partial wave.

  11. Nucleon-nucleon scattering with the complex scaling method and realistic interactions

    NASA Astrophysics Data System (ADS)

    Papadimitriou, G.; Vary, J. P.

    2015-02-01

    We demonstrate the validity of the complex scaling method for realistic strong, nonlocal, nucleon-nucleon interactions by comparing the deuteron bound state and nucleon-nucleon scattering phase shifts with results from other high-precision methods. This opens a pathway for the simultaneous ab initio solutions of the nuclear bound and scattering problems within a unified framework.

  12. On the resonance structure in nucleon-nucleon scattering

    NASA Astrophysics Data System (ADS)

    Kloet, W. M.; Tjon, J. A.

    1981-10-01

    A possible explanation of resonance-like structure in 1D 2 and 3F 3 proton-proton phase parameters at medium energy is suggested by the analysis of an exactly soluble coupled channel model. Looping in the Argand plot is mainly due to the nucleon-delta branch cut. This effect is already present in the NΔ box diagram, but is modified by higher order multiple scattering. Poles occur close to the NΔ branch point and originate from left-hand singularities in the unphysical sheet.

  13. Study of Three-Nucleon Force Effect via Few-Nucleon Scattering

    NASA Astrophysics Data System (ADS)

    Wada, Yasunori; Sekiguchi, Kimiko; Gebauer, Uwe; Miyazaki, Jumpei; Taguchi, Takahiro; Dozono, Masanori; Sakai, Hideyuki; Sakamoto, Naruhiko; Sasano, Masaki; Shimizu, Yohei; Suzuki, Hiroshi; Uesaka, Tomohiro; Kawase, Shoichiro; Kubota, Yuki; Lee, Cheong Soo; Tang, Tsz Leung; Yako, Kentaro; Maeda, Yukie; Miki, Kenjiro; Okamura, Hiroyuki; Sakaguchi, Satoshi; Wakasa, Tomotsugu

    2016-02-01

    A complete set of deuteron analyzing powers for elastic deuteron-proton(dp) scattering at 250 and 294 MeV/nucleon has been measured. The obtained data are compared with the Faddeev calculations based on the modern nucleon-nucleon forces together with three-nucleon forces.

  14. Low-energy pion-nucleon scattering

    NASA Astrophysics Data System (ADS)

    Gibbs, W. R.; Ai, Li; Kaufmann, W. B.

    1998-02-01

    An analysis of low-energy charged pion-nucleon data from recent π+/-p experiments is presented. From the scattering lengths and the Goldberger-Miyazawa-Oehme (GMO) sum rule we find a value of the pion-nucleon coupling constant of f2=0.0756+/-0.0007. We also find, contrary to most previous analyses, that the scattering volumes for the P31 and P13 partial waves are equal, within errors, corresponding to a symmetry found in the Hamiltonian of many theories. For the potential models used, the amplitudes are extrapolated into the subthreshold region to estimate the value of the Σ term. Off-shell amplitudes are also provided.

  15. Low-energy pion-nucleon scattering

    SciTech Connect

    Gibbs, W.R.; Ai, L.; Kaufmann, W.B.

    1998-02-01

    An analysis of low-energy charged pion-nucleon data from recent {pi}{sup {plus_minus}}p experiments is presented. From the scattering lengths and the Goldberger-Miyazawa-Oehme (GMO) sum rule we find a value of the pion-nucleon coupling constant of f{sup 2}=0.0756{plus_minus}0.0007. We also find, contrary to most previous analyses, that the scattering volumes for the P{sub 31} and P{sub 13} partial waves are equal, within errors, corresponding to a symmetry found in the Hamiltonian of many theories. For the potential models used, the amplitudes are extrapolated into the subthreshold region to estimate the value of the {Sigma} term. Off-shell amplitudes are also provided. {copyright} {ital 1998} {ital The American Physical Society}

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

    SciTech Connect

    Chvojka, Jesse John

    2012-01-01

    The phenomenon of neutrino oscillation is becoming increasingly understood with results from accelerator-based and reactor-based experiments, but unanswered questions remain. The proper ordering of the neutrino mass eigenstates that compose the neutrino avor eigenstates is not completely known. We have yet to detect CP violation in neutrino mixing, which if present could help explain the asymmetry between matter and anti-matter in the universe. We also have not resolved whether sterile neutrinos, which do not interact in any Standard Model interaction, exist. Accelerator-based experiments appear to be the most promising candidates for resolving these questions; however, the ability of present and future experiments to provide answers is likely to be limited by systematic errors. A significant source of this systematic error comes from limitations in our knowledge of neutrino-nucleus interactions. Errors on cross-sections for such interactions are large, existing data is sometimes contradictory, and knowledge of nuclear effects is incomplete. One type of neutrino interaction of particular interest is charged current quasi-elastic (CCQE) scattering, which yields a final state consisting of a charged lepton and nucleon. This process, which is the dominant interaction near energies of 1 GeV, is of great utility to neutrino oscillation experiments since the incoming neutrino energy and the square of the momentum transferred to the final state nucleon, Q2, can be reconstructed using the final state lepton kinematics. To address the uncertainty in our knowledge of neutrino interactions, many experiments have begun making dedicated measurements. In particular, the MINER A experiment is studying neutrino-nucleus interactions in the few GeV region. MINERvA is a fine-grained, high precision, high statistics neutrino scattering experiment that will greatly improve our understanding of neutrino cross-sections and nuclear effects that affect the final state particles

  17. Deeply virtual Compton scattering and nucleon structure

    SciTech Connect

    M. Garcon

    2006-11-01

    Deeply Virtual Compton Scattering (DVCS) is the tool of choice to study Generalized Parton Distributions (GPD) in the nucleon. After a general introduction to the subject, a review of experimental results from various facilities is given. Following the first encouraging results, new generation dedicated experiments now allow unprecedented precision and kinematical coverage. Several new results were presented during the conference, showing significant progress in this relatively new field. Prospects for future experiments are presented. The path for the experimental determination of GPDs appears now open.

  18. Effective theories for dark matter nucleon scattering

    NASA Astrophysics Data System (ADS)

    Hisano, Junji; Nagai, Ryo; Nagata, Natsumi

    2015-05-01

    We reformulate the calculation of the dark matter-nucleon scattering cross sections based on the method of effective field theories. We assume that the scatterings are induced by the exchange of colored mediators, and construct the effective theories by integrating out the colored particles. All of the leading order matching conditions as well as the renormalization group equations are presented. We consider a Majorana fermion, and real scalar and vector bosons for the dark matter and show the results for each case. The treatment for the twist-2 operators is discussed in detail, and it is shown that the scale of evaluating their nucleon matrix elements does not have to be the hadronic scale. The effects of the QCD corrections are evaluated on the assumption that the masses of the colored mediators are much heavier than the electroweak scale. Our formulation is systematic and model-independent, and thus suitable to be implemented in numerical packages, such as micrOMEGAs and DarkSUSY.

  19. Evidence for dibaryon resonances in nucleon-nucleon scattering

    SciTech Connect

    Roberts, J.B.

    1980-01-01

    There has been a revival of interest in the subject of nucleon-nucleon resonances in the past 3 to 4 years, largely generated by experimental results from the polarized beam program at the Argonne ZGS. Evidence from experimental results and phase shift and phenomenological analyses incorporating these results regarding the existence of these resonances is summarized. 20 figures.

  20. Nucleon and deuteron scattering cross sections from 25 MV/Nucleon to 22.5 GeV/Nucleon

    NASA Technical Reports Server (NTRS)

    Townsend, L. W.; Wilson, J. W.; Bidasaria, H. B.

    1983-01-01

    Within the context of a double-folding optical potential approximation to the exact nucleus-nucleus multiple-scattering series, eikonal scattering theory is used to generate tables of nucleon and deuteron total and absorption cross sections at kinetic energies between 25 MeV/nucleon and 22.5 GeV/nucleon for use in cosmic-ray transport and shielding studies. Comparisons of predictions for nucleon-nucleus and deuteron-nucleus absorption and total cross sections with experimental data are also made.

  1. Intrinsic radial sensitivity of nucleon inelastic scattering

    NASA Astrophysics Data System (ADS)

    Kelly, J. J.

    1988-02-01

    A linear expansion analysis of the folding model transition amplitude is used to study the intrinsic sensitivity of the inelastic scattering of intermediate energy nucleons to the radial form of the neutron transition density, given known proton transition densities from electron scattering. Realistic density-dependent effective interactions are used to construct pseudodata. These pseudodata are then reanalyzed and the error matrix is used to calculate an error band for the radial transition density. This approach reveals the sensitivity of the extracted transition density to absorption, medium modifications of the interaction, and the extent and quality of the data in a manner that is largely free of the residual inaccuracies in reaction theory that complicate the analysis of real data. We find that the intrinsic radial sensitivity of nucleon inelastic scattering is best for projectile energies between 200 and 500 MeV, but is adequate to resolve the radial dependence of neutron transition densities even in the interior of heavy nuclei throughout the energy regime 100-800 MeV. We have also compared our method with scale-factor analyses which assume proportionality between neutron and proton densities. For states whose transition densities are similar in the surface, we find scaling to be accurate at the 20% level. However, for light nuclei substantial deviations beyond the first peak of the differential cross section reveal sensitivity to shape differences. This sensitivity is reduced for heavy nuclei. The model dependence of radial densities is also studied. A high-q constraint is used to analyze the contribution of incompleteness error to the deduced error bands and to reduce the model dependence.

  2. Electromagnetic Form Factors of the Nucleon and Compton Scattering

    SciTech Connect

    Charles Hyde-Wright; Cornelis De Jager

    2004-12-01

    We review the experimental and theoretical status of elastic electron scattering and elastic low-energy photon scattering (with both real and virtual photons) from the nucleon. As a consequence of new experimental facilities and new theoretical insights, these subjects are advancing with unprecedented precision. These reactions provide many important insights into the spatial distributions and correlations of quarks in the nucleon.

  3. Inelastic electron scattering from a moving nucleon

    SciTech Connect

    Kuhn, S.E.; Griffioen, K.

    1994-04-01

    The authors propose to measure inelastically scattered electrons in coincidence with spectator protons emitted backwards relative to the virtual photon direction in the reaction d(e, e{prime}p{sub s})X. In a simple spectator model, the backward proton has equal and opposite momentum to the neutron before it is struck, allowing the authors to study the dependence on kinematics and off-shell behaviour of the electron-nucleon inelastic cross section. If the photon couples to a quark in a 6-quark bag, a different dependence of the cross section on the kinematic variables (x, Q{sup 2}, and p{sub s}) can be observed. This proposed experiment requires large acceptance and beam energies above 6 GeV. It is ideally suited for the CEBAF Large Acceptance Spectrometer (CLAS).

  4. Model independent extraction of the axial mass parameter in CCQE anti neutrino-nucleon scattering

    NASA Astrophysics Data System (ADS)

    Grebe, Heather

    2013-10-01

    Neutrino oscillation studies depend on a consistent value for the axial mass. For this reason, a model-independent extraction of this parameter from quasielastic (anti)neutrino-nucleon scattering data is vital. While most studies employ a model-dependent extraction using the dipole model of the axial form factor, we present a model-independent description using the z expansion of the axial form factor. Quasielastic antineutrino scattering data on C-12 from the MiniBooNE experiment are analyzed using this model-independent description. The value found, mA = 0 .85-0 . 06 + 0 . 13 +/- 0 . 13 GeV, differs significantly from the value utilized by the MiniBooNE Collaboration, mA = 1 . 35 GeV. Advisor: Dr. Gil Paz Wayne State Univerity.

  5. Deep inelastic lepton scattering from nucleons and nuclei

    SciTech Connect

    Berger, E.L.

    1986-02-01

    A pedagogical review is presented of results obtained from inclusive deep inelastic scattering of leptons from nucleons and nuclei, with particular emphasis on open questions to be explored in future experiments.

  6. Double deeply virtual Compton scattering on nucleons and nuclei

    SciTech Connect

    Kopeliovich, B. Z.; Schmidt, Ivan; Siddikov, M.

    2010-07-01

    In this paper we evaluate the double deeply virtual Compton scattering on nucleons and nuclei in the framework of the color dipole model. Both the effects of quark and the gluon shadowing are taken into account.

  7. Nucleon-nucleon scattering at small angles, measured at ANKE-COSY

    NASA Astrophysics Data System (ADS)

    Bagdasarian, Z.

    2016-03-01

    The most accepted approach to describe nucleon-nucleon (NN) interaction is the partial wave analysis (PWA), which translates various experimental observables to the common language of the partial waves. The reliable analysis relies not only on the quality experimental data, but also on the measurements of scattering observables over preferably the full angular range. Small angle scattering has been measured for six beam energies between 0.8 and 2.4 GeV using polarized proton beam incident on both proton and deuteron unpolarized targets at COSY-ANKE. This proceeding will report on the published and preliminary results for both pp and pn scattering from this and other recent experiments at ANKE. This study aims to provide the valuable observables to the SAID group in order to improve the phenomenological understanding of the nucleon-nucleon interaction.

  8. Polarization phenomena in nucleon-nucleon scattering at intermediate and high energies including the present status of dibaryons

    SciTech Connect

    Yokosawa, A.

    1985-01-01

    We review experimental results concerning polarization phenomena in nucleon-nucleon scattering in which both the elastic scattering and hadron-production reaction are included. We also present summary of S = 0 dibaryon resonances and candidates by reviewing experimental data in the nucleon-nucleon system, ..gamma..d channel, ..pi..d elastic scattering, pp ..-->.. ..pi..d channel, deuteron break-up reactions, and narrow structures in missing-mass spectra. 93 refs., 26 figs.

  9. New results in nucleon-nucleon scattering at intermediate energies

    SciTech Connect

    Spinka, H.

    1995-01-01

    Many np elastic scattering spin observables have recently been measured between kinetic energies of about 500 and 1100 MeV at Saclay and LAMPF. These data are summarized and some new results are presented. Evidence for structure in pp observables near 2100 MeV is reviewed, and new data in this energy region are shown from SATURNE.

  10. Nucleon-nucleon scattering in a strong external magnetic field and the neutrino emissivity

    SciTech Connect

    Bavarsad, E.; Mohammadi, R.; Haghighat, M.

    2010-11-15

    The nucleon-nucleon scattering in a large magnetic background is considered to find its potential to change the neutrino emissivity of the neutron stars. For this purpose, we consider the one-pion-exchange approximation to find the nucleon-nucleon (NN) cross section in a background field as large as 10{sup 15}-10{sup 18} G. We show that the NN cross section in neutron stars with temperatures in the range 0.1-5 MeV can be changed up to the 1 order of magnitude with respect to the one in the absence of the magnetic field. In the limit of the soft neutrino emission, the neutrino emissivity can be written in terms of the NN-scattering amplitude; therefore, the large magnetic fields can dramatically change the neutrino emissivity of the neutron stars as well.

  11. Goeppert-Mayer Award Recipient: Electron Scattering and Nucleon Structure

    NASA Astrophysics Data System (ADS)

    Beise, Elizabeth

    1998-04-01

    Electron scattering from hydrogen and light nuclear targets has long been recognized as one of the best tools for understanding the electromagnetic structure of protons, neutrons and few-nucleon systems. In the last decade, considerable progress has been made in the field through advances in polarized beams and polarized targets. Improvements in polarized electron sources has made it feasible to also study the structure of the nucleon through parity-violating electron scattering, where the nucleon's neutral weak structure is probed. In this talk, a summary of the present experimental status of the nucleon's electroweak structure will be presented, with an emphasis on recent results from the MIT-Bates and Jefferson Laboratories.

  12. Ab initio many-body calculations of nucleon-4He scattering with three-nucleon forces

    DOE PAGESBeta

    Hupin, Guillaume; Langhammer, Joachim; Navratil, Petr; Quaglioni, Sofia; Calci, Angelo; Roth, Robert

    2013-11-27

    We extend the ab initio no-core shell model/resonating-group method to include three-nucleon (3N) interactions for the description of nucleon-nucleus collisions. We outline the formalism, give algebraic expressions for the 3N-force integration kernels, and discuss computational aspects of two alternative implementations. The extended theoretical framework is then applied to nucleon-4He elastic scattering using similarity-renormalization-group (SRG)-evolved nucleon-nucleon plus 3N potentials derived from chiral effective field theory. We analyze the convergence properties of the calculated phase shifts and explore their dependence upon the SRG evolution parameter. We include up to six excited states of the 4He target and find significant effects from themore » inclusion of the chiral 3N force, e.g., it enhances the spin-orbit splitting between the 3/2– and 1/2– resonances and leads to an improved agreement with the phase shifts obtained from an accurate R-matrix analysis of the five-nucleon experimental data. As a result, we find remarkably good agreement with measured differential cross sections at various energies below the d+3H threshold, while analyzing powers manifest larger deviations from experiment for certain energies and angles.« less

  13. 1S0 nucleon-nucleon scattering in the modified Weinberg approach

    NASA Astrophysics Data System (ADS)

    Epelbaum, E.; Gasparyan, A. M.; Gegelia, J.; Krebs, H.

    2015-06-01

    Nucleon-nucleon scattering in the 1 S 0 partial wave is considered in chiral effective field theory within the renormalizable formulation of a previous work (Phys. Lett. B 716, 338 (2012)) beyond the leading-order approximation. By applying subtractive renormalization, the subleading contact interaction in this channel is taken into account non-perturbatively. For a proper choice of renormalization conditions, the predicted energy dependence of the phase shift and the coefficients in the effective range expansion are found to be in a good agreement with the results of the Nijmegen partial wave analysis.

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

    SciTech Connect

    Ankowski, Artur M.

    2015-05-15

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

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

    NASA Astrophysics Data System (ADS)

    Ankowski, Artur M.

    2015-05-01

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

  16. Nucleon-nucleon scattering from dispersion relations: Next-to-next-to-leading order study

    NASA Astrophysics Data System (ADS)

    Oller, J. A.

    2016-02-01

    Nucleon-nucleon (NN ) scattering is studied by applying an approach based on the N /D method and chiral perturbation theory (ChPT), whose dynamical input per partial wave consists of the imaginary part of the NN partial-wave amplitude along the left-hand cut. The latter is calculated in one-loop ChPT up to and including next-to-next-to-leading order (NNLO). A power counting for the subtraction constants is established, which is appropriate for those subtractions attached to both the left- and the right-hand cuts. A quite good reproduction of the Nijmegen partial-wave analysis phase shifts and mixing angles results, which implies a steady improvement in the accurateness achieved by increasing the chiral order in the calculation of the dynamical input. I discuss that it is not necessary to fine tune the chiral counterterms ci determined from pion-nucleon scattering to agree with NN data, but instead one should perform the iteration of two-nucleon intermediate states in a well-defined way so as to keep proper unitarity and analyticity. It is also confirmed at NNLO the long-range correlations between the NN S -wave effective ranges and scattering lengths, when employing only once-subtracted dispersion relations, that hold up to around 10% when compared with experimental values.

  17. Unitary model for meson-nucleon scattering

    SciTech Connect

    Feuster, T.; Mosel, U.; Mosel, U.

    1998-07-01

    We extract nucleon resonance parameters from an effective Lagrangian model employing the K-matrix approximation. To this end we analyze simultaneously all available data for reactions involving the final states {pi}N, {pi}{pi}N, {eta}N, and K{Lambda} in the energy range m{sub N}+m{sub {pi}}{le}{radical} (s) {le}1.9 GeV. The background contributions are generated consistently from the relevant Feynman amplitudes, which significantly reduces the number of free parameters. The sensitivity of the parameters upon the {pi}N{endash}partial-wave analysis and the details of the Lagrangians and form factors used are discussed. {copyright} {ital 1998} {ital The American Physical Society}

  18. Nucleon-Hyperon (and YY) Scattering on the Lattice

    SciTech Connect

    Huey-Wen Lin

    2011-09-01

    Lattice QCD offers the chance to study the interactions of strange hadrons from the first principles of QCD. These NY (nucleon-hyperon) and YY (hyperon-hyperon) interactions are crucial to understanding the strange matter that may be created in extreme environments, such as the core of a neutron star. Since the fast decay of strange matter prevents experiments from providing strong constraints on the parameters of such interactions, direct theoretical calculations are especially valuable. In this presentation, I will report on the latest progress toward precision nucleon-hyperon and hyperon-hyperon scattering calculation in lattice QCD.

  19. Roy-Steiner-equation analysis of pion-nucleon scattering

    NASA Astrophysics Data System (ADS)

    Hoferichter, Martin; Ruiz de Elvira, Jacobo; Kubis, Bastian; Meißner, Ulf-G.

    2016-04-01

    We review the structure of Roy-Steiner equations for pion-nucleon scattering, the solution for the partial waves of the t-channel process ππ → N ¯ N, as well as the high-accuracy extraction of the pion-nucleon S-wave scattering lengths from data on pionic hydrogen and deuterium. We then proceed to construct solutions for the lowest partial waves of the s-channel process πN → πN and demonstrate that accurate solutions can be found if the scattering lengths are imposed as constraints. Detailed error estimates of all input quantities in the solution procedure are performed and explicit parameterizations for the resulting low-energy phase shifts as well as results for subthreshold parameters and higher threshold parameters are presented. Furthermore, we discuss the extraction of the pion-nucleon σ-term via the Cheng-Dashen low-energy theorem, including the role of isospin-breaking corrections, to obtain a precision determination consistent with all constraints from analyticity, unitarity, crossing symmetry, and pionic-atom data. We perform the matching to chiral perturbation theory in the subthreshold region and detail the consequences for the chiral convergence of the threshold parameters and the nucleon mass.

  20. Quantum Monte Carlo Calculations of Nucleon-Nucleus Scattering

    NASA Astrophysics Data System (ADS)

    Wiringa, R. B.; Nollett, Kenneth M.; Pieper, Steven C.; Brida, I.

    2009-10-01

    We report recent quantum Monte Carlo (variational and Green's function) calculations of elastic nucleon-nucleus scattering. We are adding the cases of proton-^4He, neutron-^3H and proton-^3He scattering to a previous GFMC study of neutron-^4He scattering [1]. To do this requires generalizing our methods to include long-range Coulomb forces and to treat coupled channels. The two four-body cases can be compared to other accurate four-body calculational methods such as the AGS equations and hyperspherical harmonic expansions. We will present results for the Argonne v18 interaction alone and with Urbana and Illinois three-nucleon potentials. [4pt] [1] K.M. Nollett, S. C. Pieper, R.B. Wiringa, J. Carlson, and G.M. Hale, Phys. Rev. Lett. 99, 022502 (2007)

  1. The method of unitary clothing transformations in the theory of nucleon-nucleon scattering

    NASA Astrophysics Data System (ADS)

    Dubovyk, I.; Shebeko, A.

    2010-04-01

    The clothing procedure, put forward in quantum field theory (QFT) by Greenberg and Schweber, is applied for the description of nucleon-nucleon (N -N) scattering. We consider pseudoscalar (π and η), vector (ρ and ω) and scalar (δ and σ) meson fields interacting with 1/2 spin (N and N) fermion ones via the Yukawa-type couplings to introduce trial interactions between “bare” particles. The subsequent unitary clothing transformations (UCTs) are found to express the total Hamiltonian through new interaction operators that refer to particles with physical (observable) properties, the so-called clothed particles. In this work, we are focused upon the Hermitian and energy-independent operators for the clothed nucleons, being built up in the second order in the coupling constants. The corresponding analytic expressions in momentum space are compared with the separate meson contributions to the one-boson-exchange potentials in the meson theory of nuclear forces. In order to evaluate the T matrix of the N-N scattering we have used an equivalence theorem that enables us to operate in the clothed particle representation (CPR) instead of the bare particle representation (BPR) with its huge amount of virtual processes. We have derived the Lippmann-Schwinger(LS)-type equation for the CPR elements of the T-matrix for a given collision energy in the two-nucleon sector of the Hilbert space H of hadronic states and elaborated a code for its numerical solution in momentum space.

  2. The Method of Unitary Clothing Transformations in the Theory of Nucleon-Nucleon Scattering

    NASA Astrophysics Data System (ADS)

    Dubovyk, I.; Shebeko, O.

    2010-12-01

    The clothing procedure, put forward in quantum field theory (QFT) by Greenberg and Schweber, is applied for the description of nucleon-nucleon ( N- N) scattering. We consider pseudoscalar ( π and η), vector ( ρ and ω) and scalar ( δ and σ) meson fields interacting with 1/2 spin ( N and {bar{N}}) fermion ones via the Yukawa-type couplings to introduce trial interactions between “bare” particles. The subsequent unitary clothing transformations are found to express the total Hamiltonian through new interaction operators that refer to particles with physical (observable) properties, the so-called clothed particles. In this work, we are focused upon the Hermitian and energy-independent operators for the clothed nucleons, being built up in the second order in the coupling constants. The corresponding analytic expressions in momentum space are compared with the separate meson contributions to the one-boson-exchange potentials in the meson theory of nuclear forces. In order to evaluate the T matrix of the N- N scattering we have used an equivalence theorem that enables us to operate in the clothed particle representation (CPR) instead of the bare particle representation with its large amount of virtual processes. We have derived the Lippmann-Schwinger type equation for the CPR elements of the T-matrix for a given collision energy in the two-nucleon sector of the Hilbert space {mathcal{H}} of hadronic states.

  3. Nucleon polarizabilities: From Compton scattering to hydrogen atom

    NASA Astrophysics Data System (ADS)

    Hagelstein, Franziska; Miskimen, Rory; Pascalutsa, Vladimir

    2016-05-01

    We review the current state of knowledge of the nucleon polarizabilities and of their role in nucleon Compton scattering and in hydrogen spectrum. We discuss the basic concepts, the recent lattice QCD calculations and advances in chiral effective-field theory. On the experimental side, we review the ongoing programs aimed to measure the nucleon (scalar and spin) polarizabilities via the Compton scattering processes, with real and virtual photons. A great part of the review is devoted to the general constraints based on unitarity, causality, discrete and continuous symmetries, which result in model-independent relations involving nucleon polarizabilities. We (re-)derive a variety of such relations and discuss their empirical value. The proton polarizability effects are presently the major sources of uncertainty in the assessment of the muonic hydrogen Lamb shift and hyperfine structure. Recent calculations of these effects are reviewed here in the context of the "proton-radius puzzle". We conclude with summary plots of the recent results and prospects for the near-future work.

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

    SciTech Connect

    Patrick, Cheryl

    2016-01-01

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

  5. Virtual Compton scattering off the nucleon at low energies

    SciTech Connect

    Scherer, S.; Korchin, A.Y.; Koch, J.H.

    1996-08-01

    We investigate the low-energy behavior of the four-point Green{close_quote}s function {Gamma}{sup {mu}{nu}} describing virtual Compton scattering off the nucleon. Using Lorentz invariance, gauge invariance, and crossing symmetry, we derive the leading terms of an expansion of the operator in the four-momenta {ital q} and {ital q}{sup {prime}} of the initial and final photon, respectively. The model-independent result is expressed in terms of the electromagnetic form factors of the free nucleon, i.e., on-shell information which one obtains from electron-nucleon scattering experiments. Model-dependent terms appear in the operator at {ital O}({ital q}{sub {alpha}}{ital q}{sub {beta}}{sup {prime}}), whereas the orders {ital O}({ital q}{sub {alpha}}{ital q}{sub {beta}}) and {ital O}({ital q}{sub {alpha}}{sup {prime}}{ital q}{sub {beta}}{sup {prime}}) are contained in the low-energy theorem for {Gamma}{sup {mu}{nu}}, i.e., no new parameters appear. We discuss the leading terms of the matrix element and comment on the use of on-shell equivalent electromagnetic vertices in the calculation of {open_quote}{open_quote}Born terms{close_quote}{close_quote} for virtual Compton scattering. {copyright} {ital 1996 The American Physical Society.}

  6. Kaon-nucleon scattering in three-dimensional technique

    NASA Astrophysics Data System (ADS)

    Salam, Agus; Fachruddin, Imam

    2016-03-01

    Kaon-nucleon (KN) scattering is formulated in the three-dimensional (3D) momentum space, in which the basis state is not expanded into partial waves. Based on this basis the Lippmann-Schwinger equation for the T-matrix is evaluated. We obtain as final equation for the T-matrix elements a set of two coupled integral equations in two variables, which are the momentum's magnitude and the scattering angle. Calculations for the differential cross section and some spin observables are shown, for which we employ a hadrons exchange model with the second order contributions only.

  7. Compton scattering and nucleon polarisabilities in chiral EFT: Status and future

    NASA Astrophysics Data System (ADS)

    Grießhammer, Harald W.; McGovern, Judith A.; Phillips, Daniel R.

    2016-05-01

    We review theoretical progress and prospects for determining the nucleon's static dipole polarisabilities from Compton scattering on few-nucleon targets, including new values; see Refs. [1-5] for details and a more thorough bibliography.

  8. Nucleon-nucleon correlations and multiquark cluster effects in semi-inclusive deep inelastic lepton scattering off

    SciTech Connect

    Simula, S.

    1994-04-01

    Semi-inclusive deep inelastic lepton scattering off nuclei is investigated assuming that virtual boson absorption occurs on a hadronic cluster which can be either a two-nucleon correlated pair or a six-quark bag. The differences in the energy distribution of nucleons produced in backward and forward directions are analyzed both at x<1 and x>1.

  9. Nucleon Compton scattering in the Dyson-Schwinger approach

    NASA Astrophysics Data System (ADS)

    Eichmann, Gernot; Fischer, Christian S.

    2013-02-01

    We analyze the nucleon’s Compton scattering amplitude in the Dyson-Schwinger/Faddeev approach. We calculate a subset of diagrams that implements the nonperturbative handbag contribution as well as all t-channel resonances. At the quark level, these ingredients are represented by the quark Compton vertex whose analytic properties we study in detail. We derive a general form for a fermion two-photon vertex that is consistent with its Ward-Takahashi identities and free of kinematic singularities, and we relate its transverse part to the on-shell nucleon Compton amplitude. We solve an inhomogeneous Bethe-Salpeter equation for the quark Compton vertex in rainbow-ladder truncation and implement it in the nucleon Compton scattering amplitude. The remaining ingredients are the dressed quark propagator and the nucleon’s bound-state amplitude which are consistently solved from Dyson-Schwinger and covariant Faddeev equations. We verify numerically that the resulting quark Compton vertex and nucleon Compton amplitude both reproduce the πγγ transition form factor when the pion pole in the t channel is approached.

  10. Virtual Compton scattering off the nucleon in chiral perturbation theory

    SciTech Connect

    Hemmert, T.R.; Holstein, B.R.; Knoechlein, G.; Scherer, S.

    1997-03-01

    We investigate the spin-independent part of the virtual Compton scattering (VCS) amplitude off the nucleon within the framework of chiral perturbation theory. We perform a consistent calculation to third order in external momenta according to Weinberg`s power counting. With this calculation we can determine the second- and fourth-order structure-dependent coefficients of the general low-energy expansion of the spin-averaged VCS amplitude based on gauge invariance, crossing symmetry, and the discrete symmetries. We discuss the kinematical regime to which our calculation can be applied and compare our expansion with the multipole expansion by Guichon, Liu, and Thomas. We establish the connection of our calculation with the generalized polarizabilities of the nucleon where it is possible. {copyright} {ital 1997} {ital The American Physical Society}

  11. On triplet low-energy parameters of nucleon-nucleon scattering

    SciTech Connect

    Babenko, V. A.; Petrov, N. M.

    2006-09-15

    Triplet low-energy parameters of neutron-proton scattering, including high-order shape parameters, are calculated on the basis of approximating the effective-range function k cot {delta}{sub t} by polynomials and rational functions with the aid of the latest experimental data on phase shifts from the SAID nucleon-nucleon database. With the resulting values of the low-energy parameters, a good description of phase shifts over a broad energy interval is obtained by using the effective-range expansion featuring a small number of terms. The properties of the deuteron that were calculated on the basis of the values found for the triplet low-energy parameters of scattering agree very well with experimental values. The triplet low-energy parameters and the properties of the deuteron that were obtained here by using present-day data from the SAID database differ markedly from the analogous results obtained for data of the Nijmegen group. Possible reasons behind this discrepancy are discussed. Highly precise new approximate formulas for determining the shape parameter v{sub 2} are proposed and are shown to be efficient in calculations. The effective-range expansion for the D wave is considered, and preliminary results of calculations of low-energy scattering parameters for this case are obtained.

  12. Compton scattering, meson exchange, and the polarizabilities of bound nucleons

    NASA Astrophysics Data System (ADS)

    Feldman, G.; Mellendorf, K. E.; Eisenstein, R. A.; Federspiel, F. J.; Garino, G.; Igarashi, R.; Kolb, N. R.; Lucas, M. A.; MacGibbon, B. E.; Mize, W. K.; Nathan, A. M.; Pywell, R. E.; Wells, D. P.

    1996-11-01

    Elastic photon scattering cross sections on 16O have been measured in the energy range 27-108 MeV. These data are inconsistent with a conventional interpretation in which the electric and magnetic polarizabilities of the bound nucleon are unchanged from the free values and the meson-exchange seagull amplitude is taken in the zero-energy limit. Agreement with the data can be achieved by invoking either strongly modified polarizabilities or a substantial energy dependence to the meson-exchange seagull amplitude. It is argued that these seemingly different explanations are experimentally indistinguishable and probably physically equivalent.

  13. Measurement of Neutrino-Nucleon Neutral-Current Elastic Scattering Cross-section at SciBooNE

    SciTech Connect

    Takei, Hideyuki; /Tokyo Inst. Tech.

    2009-02-01

    In this thesis, results of neutrino-nucleon neutral current (NC) elastic scattering analysis are presented. Neutrinos interact with other particles only with weak force. Measurement of cross-section for neutrino-nucleon reactions at various neutrino energy are important for the study of nucleon structure. It also provides data to be used for beam flux monitor in neutrino oscillation experiments. The cross-section for neutrino-nucleon NC elastic scattering contains the axial vector form factor G{sub A}(Q{sup 2}) as well as electromagnetic form factors unlike electromagnetic interaction. G{sub A} is propotional to strange part of nucleon spin ({Delta}s) in Q{sup 2} {yields} 0 limit. Measurement of NC elastic cross-section with smaller Q{sup 2} enables us to access {Delta}s. NC elastic cross-sections of neutrino-nucleon and antineutrino-nucleon were measured earlier by E734 experiment at Brookheaven National Laboratory (BNL) in 1987. In this experiment, cross-sections were measured in Q{sup 2} > 0.4 GeV{sup 2} region. Result from this experiment was the only published data for NC elastic scattering cross-section published before our experiment. SciBooNE is an experiment for the measurement of neutrino-nucleon scattering cross-secitons using Booster Neutrino Beam (BNB) at FNAL. BNB has energy peak at 0.7 GeV. In this energy region, NC elastic scattering, charged current elastic scattering, charged current pion production, and neutral current pion production are the major reaction branches. SciBar, electromagnetic calorimeter, and Muon Range Detector are the detectors for SciBooNE. The SciBar consists of finely segmented scintillators and 14336 channels of PMTs. It has a capability to reconstruct particle track longer than 8 cm and separate proton from muons and pions using energy deposit information. Signal of NC elastic scattering is a single proton track. In {nu}p {yields} {nu}p process, the recoil proton is detected. On the other hand, most of {nu}n {yields} {nu

  14. Computations of the collapse of a stellar iron core allowing for the absorption, emission, and scattering of electron neutrinos and anti-neutrinos

    NASA Astrophysics Data System (ADS)

    Aksenov, A. G.; Chechetkin, V. M.

    2012-03-01

    The collapse of the iron core of a star with mass 1.4 M ⊙ is computed. The initial model was chosen to be polytropic, P ∝ ρ 1+1/ n , with n = 3. The equation of state takes into account the equilibrium radiation of photons, a mixture of Fermi gases comprised of free nucleons and ideal gases comprised of nuclei (Fe, He) in equilibrium with respect to nuclear reactions, and electron-positron gas. The transport equation for electron neutrinos and anti-neutrinos is also included. The absorption and emission of neutrinos and anti-neutrinos with the participation of free nucleons and nuclei is taken into account, as well as scattering on electrons. The main goal of this study is to develop a numerical method for the joint solution of the gas-dynamical equations formatter and the Boltzmann kinetic equations for the distribution functions of various types of neutrinos in both optically thin and optically thick regions. The spherically symmetrical case is considered, but the dependences of the distribution functions on all the phase-space variables—the mass coordinate, particle energy, cosine of the angle between the radius vector and the particle momentum, and time, ( m, ɛ, µ, t)—are retained in the description of the neutrino transport. When computing reaction rates, the exact quantum-mechanical expressions for the probabilities of processes are used, with integration over the entire momentum phase space. The gas-dynamical variables depend on the mass coordinate and time, ( m, t). The solution yields neutrino light curves, which have narrow maximum with characteristic widths ≈10 ms. This makes it possible to place constraints on the mass of the electron neutrino based on the detection of short bursts of radiation, ≲4 eV. Part of the neutrino energy is absorbed in the envelope of the stellar core (˜1050 erg). This is associated with the higher mean neutrino energies in this model, which is more exact than models with neutrino thermal conductivity. This

  15. Low-energy theorems for nucleon-nucleon scattering at unphysical pion masses

    NASA Astrophysics Data System (ADS)

    Baru, V.; Epelbaum, E.; Filin, A. A.; Gegelia, J.

    2015-07-01

    The longest-range part of the nuclear force from the one-pion exchange governs the energy dependence of the scattering amplitude in the near-threshold region and imposes correlations between the coefficients in the effective range expansion. These correlations may be regarded as low-energy theorems and are known to hold to a high accuracy in the neutron-proton 3S1 partial wave. We generalize the low-energy theorems to the case of unphysical pion masses and provide results for the correlations between the coefficients in the effective range expansion in this partial wave for pion masses up to Mπ˜400 MeV . We discuss the implications of our findings for the available and upcoming lattice-quantum-chromodynamics simulations of two-nucleon observables.

  16. Low-energy theorems for nucleon-nucleon scattering at Mπ=450 MeV

    NASA Astrophysics Data System (ADS)

    Baru, V.; Epelbaum, E.; Filin, A. A.

    2016-07-01

    We apply the low-energy theorems to analyze the recent lattice QCD results for the two-nucleon system at a pion mass of Mπ≃450 MeV obtained by the NPLQCD Collaboration. We find that the binding energies of the deuteron and dineutron are inconsistent with the low-energy behavior of the corresponding phase shifts within the quoted uncertainties and vice versa. Using the binding energies of the deuteron and dineutron as input, we employ the low-energy theorems to predict the phase shifts and extract the scattering length and the effective range in the S31 and S10 channels. Our results for these quantities are consistent with those obtained by the NPLQCD Collaboration from effective field theory analyses but are in conflict with their determination based on the effective-range approximation.

  17. {eta}-Nucleon scattering length and effective range uncertainties

    SciTech Connect

    Green, A.M.; Wycech, S.

    2005-01-01

    The coupled {eta}N, {pi}N, {gamma}N, {pi}{pi}N system is described by a K-matrix method. The parameters in this model are adjusted to get an optimal fit to {pi}N{yields}{pi}N, {pi}N{yields}{eta}N, {gamma}N{yields}{pi}N, and {gamma}N{yields}{eta}N data in an energy range of about 100 MeV or so each side of the {eta} threshold. Compared with our earlier analysis, we now utilize recent Crystal Ball data. However, the outcome confirms our previous result that the {eta}-nucleon scattering length a is large with a value of 0.91(6)+i 0.27(2) fm.

  18. Measurement of Muon Antineutrino Quasielastic Scattering on a Hydrocarbon Target at Eν˜3.5GeV

    NASA Astrophysics Data System (ADS)

    Fields, L.; Chvojka, J.; Aliaga, L.; Altinok, O.; Baldin, B.; Baumbaugh, A.; Bodek, A.; Boehnlein, D.; Boyd, S.; Bradford, R.; Brooks, W. K.; Budd, H.; Butkevich, A.; Martinez Caicedo, D. A.; Castromonte, C. M.; Christy, M. E.; Chung, H.; Clark, M.; da Motta, H.; Damiani, D. S.; Danko, I.; Datta, M.; Day, M.; DeMaat, R.; Devan, J.; Draeger, E.; Dytman, S. A.; Díaz, G. A.; Eberly, B.; Edmondson, D. A.; Felix, J.; Fitzpatrick, T.; Fiorentini, G. A.; Gago, A. M.; Gallagher, H.; George, C. A.; Gielata, J. A.; Gingu, C.; Gobbi, B.; Gran, R.; Grossman, N.; Hanson, J.; Harris, D. A.; Heaton, J.; Higuera, A.; Howley, I. J.; Hurtado, K.; Jerkins, M.; Kafka, T.; Kaisen, J.; Kanter, M. O.; Keppel, C. E.; Kilmer, J.; Kordosky, M.; Krajeski, A. H.; Kulagin, S. A.; Le, T.; Lee, H.; Leister, A. G.; Locke, G.; Maggi, G.; Maher, E.; Manly, S.; Mann, W. A.; Marshall, C. M.; McFarland, K. S.; McGivern, C. L.; McGowan, A. M.; Mislivec, A.; Morfín, J. G.; Mousseau, J.; Naples, D.; Nelson, J. K.; Niculescu, G.; Niculescu, I.; Ochoa, N.; O'Connor, C. D.; Olsen, J.; Osmanov, B.; Osta, J.; Palomino, J. L.; Paolone, V.; Park, J.; Patrick, C. E.; Perdue, G. N.; Peña, C.; Rakotondravohitra, L.; Ransome, R. D.; Ray, H.; Ren, L.; Rodrigues, P. A.; Rude, C.; Sassin, K. E.; Schellman, H.; Schmitz, D. W.; Schneider, R. M.; Schulte, E. C.; Simon, C.; Snider, F. D.; Snyder, M. C.; Sobczyk, J. T.; Solano Salinas, C. J.; Tagg, N.; Tan, W.; Tice, B. G.; Tzanakos, G.; Velásquez, J. P.; Walding, J.; Walton, T.; Wolcott, J.; Wolthuis, B. A.; Woodward, N.; Zavala, G.; Zeng, H. B.; Zhang, D.; Zhu, L. Y.; Ziemer, B. P.

    2013-07-01

    We have isolated ν¯μ charged-current quasielastic (QE) interactions occurring in the segmented scintillator tracking region of the MINERvA detector running in the NuMI neutrino beam at Fermilab. We measure the flux-averaged differential cross section, dσ/dQ2, and compare to several theoretical models of QE scattering. Good agreement is obtained with a model where the nucleon axial mass, MA, is set to 0.99GeV/c2 but the nucleon vector form factors are modified to account for the observed enhancement, relative to the free nucleon case, of the cross section for the exchange of transversely polarized photons in electron-nucleus scattering. Our data at higher Q2 favor this interpretation over an alternative in which the axial mass is increased.

  19. Measurement of Muon Antineutrino Quasielastic Scattering on a Hydrocarbon Target at Eν~3.5 GeV

    DOE PAGESBeta

    Fields, L.; Chvojka, J.; Aliaga, L.; Altinok, O.; Baldin, B.; Baumbaugh, A.; Bodek, A.; Boehnlein, D.; Boyd, S.; Bradford, R.; et al

    2013-07-11

    We have isolated ν¯μ charged-current quasielastic (QE) interactions occurring in the segmented scintillator tracking region of the MINERvA detector running in the NuMI neutrino beam at Fermilab. We measure the flux-averaged differential cross section, dσ/dQ², and compare to several theoretical models of QE scattering. Good agreement is obtained with a model where the nucleon axial mass, MA, is set to 0.99 GeV/c² but the nucleon vector form factors are modified to account for the observed enhancement, relative to the free nucleon case, of the cross section for the exchange of transversely polarized photons in electron-nucleus scattering. Our data at highermore » Q² favor this interpretation over an alternative in which the axial mass is increased.« less

  20. Ab Initio Many-Body Calculations Of Nucleon-Nucleus Scattering

    SciTech Connect

    Quaglioni, S; Navratil, P

    2008-12-17

    We develop a new ab initio many-body approach capable of describing simultaneously both bound and scattering states in light nuclei, by combining the resonating-group method with the use of realistic interactions, and a microscopic and consistent description of the nucleon clusters. This approach preserves translational symmetry and Pauli principle. We outline technical details and present phase shift results for neutron scattering on {sup 3}H, {sup 4}He and {sup 10}Be and proton scattering on {sup 3,4}He, using realistic nucleon-nucleon (NN) potentials. Our A = 4 scattering results are compared to earlier ab initio calculations. We find that the CD-Bonn NN potential in particular provides an excellent description of nucleon-{sup 4}He S-wave phase shifts. We demonstrate that a proper treatment of the coupling to the n-{sup 10}Be continuum is successful in explaining the parity-inverted ground state in {sup 11}Be.

  1. The pion nucleon scattering lengths from pionic hydrogen and deuterium

    NASA Astrophysics Data System (ADS)

    Schröder, H.-Ch.; Badertscher, A.; Goudsmit, P. F. A.; Janousch, M.; Leisi, H. J.; Matsinos, E.; Sigg, D.; Zhao, Z. G.; Chatellard, D.; Egger, J.-P.; Gabathuler, K.; Hauser, P.; Simons, L. M.; Rusi El Hassani, A. J.

    2001-07-01

    This is the final publication of the ETH Zurich Neuchâtel PSI collaboration on the pionic hydrogen and deuterium precision X-ray experiments. We describe the recent hydrogen 3 p 1 s measurement, report on the determination of the Doppler effect correction to the transition line width, analyze the deuterium shift measurement and discuss implications of the combined hydrogen and deuterium results. From the pionic hydrogen 3 p 1 s transition experiments we obtain the strong-interaction energy level shift \\varepsilon_{1s} = -7.108±0.013 (stat.)±0.034 (syst.) eV and the total decay width Γ_{1s} = 0.868±0.040 (stat.)±0.038 (syst.) eV of the 1s state. Taking into account the electromagnetic corrections we find the hadronic π N s-wave scattering amplitude a_{π-prightarrowπ-p} = 0.0883±0.0008 m_{π}^{-1} for elastic scattering and a_{π-prightarrowπ0n} = -0.128±0.006 m_{π} ^{-1} for single charge exchange, respectively. We then combine the pionic hydrogen results with the 1 s level shift measurement on pionic deuterium and test isospin symmetry of the strong interaction: our data are still compatible with isospin symmetry. The isoscalar and isovector π N scattering lengths (within the framework of isospin symmetry) are found to be b_0 = -0.0001^{+0.0009}_{-0.0021} m_{π}^{-1} and b1 = -0.0885^{+0.0010}_{-0.0021} m_{π} ^{-1}, respectively. Using the GMO sum rule, we obtain from b_1 a new value of the π N coupling constant (g_{π N} = 13.21_{-0.05}^{+0.11}) from which follows the Goldberger Treiman discrepancy Δ_{{GT}} =0.027_{-0.008}^{+0.012}. The new values of b_0 and g_{π N} imply an increase of the nucleon sigma term by at least 9 MeV.

  2. Low-Energy Parameters of the Nucleon-Nucleon Scattering and Deuteron Properties, Electromagnetic Interactions with Bound Systems

    NASA Astrophysics Data System (ADS)

    Shebeko, A.; Dubovik, E.

    2013-08-01

    One more application of the method of unitary clothing transformations (UCT's) in the theory of nucleon-nucleon ( N - N) interaction has been presented. We have extended our previous analysis (Dubovik and Shebeko in Few-Body Syst 48:109-142, 2010) of the N - N scattering below the pion production threshold to treat the neutron-proton ( n - p) scattering at low energies and the deuteron static properties. Our calculations of deuteron magnetic and quadrupole moments have been carried out in the framework of a gauge independent description of electromagnetic (EM) interactions with nuclei (bound systems) using the clothed particle representation of the Hamiltonian, the boost and EM current density operators for the n-p system.

  3. Extra dimensions, SN1987a, and nucleon-nucleon scattering data

    SciTech Connect

    Christoph Hanhart; Daniel R. Phillips; Sanjay Reddy; Martin J. Savage

    2001-02-01

    One of the strongest constraints on the existence of large, compact, ''gravity-only'' dimensions comes from SN1987a. If the rate of energy loss into these putative extra dimensions is too high, then the neutrino pulse from the supernova will differ from that actually seen. The dominant mechanism for the production of Kaluza-Klein gravitons and dilatons in the supernova is via gravistrahlung and dilastrahlung from the nucleon-nucleon system. In this paper we compute the rates for these processes in a model-independent way using low-energy theorems which relate the emissivities to the measured nucleon-nucleon cross section. This is possible because for soft gravitons and dilatons the leading contribution to the energy-loss rate is from graphs in which the gravitational radiation is produced from external nucleon legs. Previous calculations neglected these mechanisms. We re-evaluate the bounds on toroidally-compactified ''gravity-only'' dimensions (GODs), and find that consistency with the observed SN1987a neutrino signal requires that if there are two such dimensions then their radius must be less than 1 micron.

  4. Directional Antineutrino Detection

    NASA Astrophysics Data System (ADS)

    Safdi, B. R.; Suerfu, J.

    2014-12-01

    We propose the first truly directional antineutrino detector for antineutrinos near the threshold for the inverse beta decay (IBD) of hydrogen, with potential applications including the spatial mapping of geo-neutrinos, searches for stellar antineutrinos, and the monitoring of nuclear reactors. The detector consists of adjacent and separated target and neutron-capture layers. The IBD events, which result in a neutron and a positron, take place in the target layers. These layers are thin enough so that the neutrons escape without scattering elastically. The neutrons are detected in the thicker neutron-capture layers. The location of the IBD event is determined from the energy deposited by the positron as it slows in the medium and from the two gamma rays that come from the positron annihilation. Since the neutron recoils in the direction of the antineutrino's motion, a line may then be drawn between the IBD event location and the neutron-capture location to approximate the antineutrino's velocity. In some events, we may even measure the positron's velocity, which further increases our ability to reconstruct the antineutrino's direction of motion. Our method significantly improves upon previous methods by allowing the neutron to freely travel a long distance before diffusing and being captured. Moreover, our design is a straightforward modification of existing antineutrino detectors; a prototype could easily be built with existing technology. We verify our design through Monte Carlo simulations in Geant4, using commercially-available boron-loaded plastic scintillators for the target and neutron-capture layer materials. We are able to discriminate from background using multiple coincidence signatures within a short, ~microsecond time interval. We conclude that the detector could likely operate above ground with minimal shielding.

  5. Measurements of parity-violating asymmetries in electron-deuteron scattering in the nucleon resonance region.

    PubMed

    Wang, D; Pan, K; Subedi, R; Deng, X; Ahmed, Z; Allada, K; Aniol, K A; Armstrong, D S; Arrington, J; Bellini, V; Beminiwattha, R; Benesch, J; Benmokhtar, F; Camsonne, A; Canan, M; Cates, G D; Chen, J-P; Chudakov, E; Cisbani, E; Dalton, M M; de Jager, C W; De Leo, R; Deconinck, W; Deur, A; Dutta, C; El Fassi, L; Flay, D; Franklin, G B; Friend, M; Frullani, S; Garibaldi, F; Giusa, A; Glamazdin, A; Golge, S; Grimm, K; Hafidi, K; Hansen, O; Higinbotham, D W; Holmes, R; Holmstrom, T; Holt, R J; Huang, J; Hyde, C E; Jen, C M; Jones, D; Kang, H; King, P; Kowalski, S; Kumar, K S; Lee, J H; LeRose, J J; Liyanage, N; Long, E; McNulty, D; Margaziotis, D J; Meddi, F; Meekins, D G; Mercado, L; Meziani, Z-E; Michaels, R; Mihovilovic, M; Muangma, N; Myers, K E; Nanda, S; Narayan, A; Nelyubin, V; Nuruzzaman; Oh, Y; Parno, D; Paschke, K D; Phillips, S K; Qian, X; Qiang, Y; Quinn, B; Rakhman, A; Reimer, P E; Rider, K; Riordan, S; Roche, J; Rubin, J; Russo, G; Saenboonruang, K; Saha, A; Sawatzky, B; Shahinyan, A; Silwal, R; Sirca, S; Souder, P A; Suleiman, R; Sulkosky, V; Sutera, C M; Tobias, W A; Urciuoli, G M; Waidyawansa, B; Wojtsekhowski, B; Ye, L; Zhao, B; Zheng, X

    2013-08-23

    We report on parity-violating asymmetries in the nucleon resonance region measured using inclusive inelastic scattering of 5-6 GeV longitudinally polarized electrons off an unpolarized deuterium target. These results are the first parity-violating asymmetry data in the resonance region beyond the Δ(1232). They provide a verification of quark-hadron duality-the equivalence of the quark- and hadron-based pictures of the nucleon-at the (10-15)% level in this electroweak observable, which is dominated by contributions from the nucleon electroweak γZ interference structure functions. In addition, the results provide constraints on nucleon resonance models relevant for calculating background corrections to elastic parity-violating electron scattering measurements. PMID:24016222

  6. Ultrahigh energy neutrino-nucleon scattering and parton distributions at small x

    SciTech Connect

    Henley, Ernest M.; Jalilian-Marian, Jamal

    2006-05-01

    The cross section for ultrahigh energy neutrino-nucleon scattering is very sensitive to the parton distributions at very small values of Bjorken x (x{<=}10{sup -4}). We numerically investigate the effects of modifying the behavior of the gluon distribution function at very small x in the DGLAP evolution equation. We then use the Color Glass Condensate formalism to calculate the neutrino-nucleon cross section at ultrahigh energies and compare the result with those based on modification of DGLAP evolution equation.

  7. Parity-Violating Electron Scattering and the Electric and Magnetic Strange Form Factors of the Nucleon

    SciTech Connect

    Armstrong, David S.; McKeown, Robert

    2012-11-01

    Measurement of the neutral weak vector form factors of the nucleon provides unique access to the strange quark content of the nucleon. These form factors can be studied using parity-violating electron scattering. A comprehensive program of experiments has been performed at three accelerator laboratories to determine the role of strange quarks in the electromagnetic form factors of the nucleon. This article reviews the remarkable technical progress associated with this program, describes the various methods used in the different experiments, and summarizes the physics results along with recent theoretical calculations.

  8. Azimuthal and single spin asymmetry in deep-inelasticlepton-nucleon scattering

    SciTech Connect

    Liang, Zuo-tang; Wang, Xin-Nian

    2006-09-21

    The collinear expansion technique is generalized to thefactorization of unintegrated parton distributions and other higher twistparton correlations from the corresponding collinear hard parts thatinvolve multiple parton final state interaction. Such a generalizedfactorization provides a consistent approach to the calculation ofinclusive and semi-inclusive cross sections of deep-inelasticlepton-nucleon scattering. As an example, the azimuthal asymmetry iscalculated to the order of 1/Q in semi-inclusive deeply inelasticlepton-nucleon scattering with transversely polarized target. Anon-vanishing single-spin asymmetry in the "triggered inclusive process"is predicted to be 1/Q suppressed with a part of the coefficient relatedto a moment of the Sivers function.

  9. Isospin breaking in low-energy pion-nucleon scattering

    SciTech Connect

    Gibbs, W.R.; Ai, L.; Kaufmann, W.B.

    1995-05-08

    We have analyzed low-energy pion-nucleon data for isospin invariance by comparing charge-exchange amplitudes derived from charge-exchange data with those predicted from recent {pi}{sup {plus_minus}}{ital p} elastic data through the application of isospin invariance. A discrepancy of the order of 7% is observed beyond the contributions of the {pi}{sup {plus_minus}}{ital p} Coulomb interaction and the hadronic mass differences.

  10. Polarized lepton-nucleon elastic scattering and a search for a light scalar boson

    NASA Astrophysics Data System (ADS)

    Liu, Yu-Sheng; Miller, Gerald A.

    2015-09-01

    Lepton-nucleon elastic scattering, using the one-photon and one-scalar-boson exchange mechanisms considering all possible polarizations, is used to study searches for a new scalar boson and suggest new measurements of the nucleon form factors. A new light scalar boson, which feebly couples to leptons and nucleons, may account for the proton radius and muon g -2 puzzles. We show that the scalar boson produces relatively large effects in a certain kinematic region when using sufficient control of lepton and nucleon spin polarization. We generalize current techniques to measure the ratio GE:GM and present a new method to separately measure GM2 and GE2 using polarized incoming and outgoing muons.

  11. Comparison of exact and approximate evaluations of the single-scattering integral in nucleon-deuteron elastic scattering

    NASA Technical Reports Server (NTRS)

    Wilson, J. W.

    1972-01-01

    The exact nucleon-deuteron elastic single scattering integral was calculated numerically in order to evaluate errors in sticking factor approximations. A similar analysis made by using S wave separable potentials concluded that errors for these approximations were negligible except near backward angles where they were found to be about 10 percent.

  12. Measurements of Parity-Violating Asymmetries in Electron-Deuteron Scattering in the Nucleon Resonance Region

    NASA Astrophysics Data System (ADS)

    Wang, D.; Pan, K.; Subedi, R.; Deng, X.; Ahmed, Z.; Allada, K.; Aniol, K. A.; Armstrong, D. S.; Arrington, J.; Bellini, V.; Beminiwattha, R.; Benesch, J.; Benmokhtar, F.; Camsonne, A.; Canan, M.; Cates, G. D.; Chen, J.-P.; Chudakov, E.; Cisbani, E.; Dalton, M. M.; de Jager, C. W.; De Leo, R.; Deconinck, W.; Deur, A.; Dutta, C.; El Fassi, L.; Flay, D.; Franklin, G. B.; Friend, M.; Frullani, S.; Garibaldi, F.; Giusa, A.; Glamazdin, A.; Golge, S.; Grimm, K.; Hafidi, K.; Hansen, O.; Higinbotham, D. W.; Holmes, R.; Holmstrom, T.; Holt, R. J.; Huang, J.; Hyde, C. E.; Jen, C. M.; Jones, D.; Kang, H.; King, P.; Kowalski, S.; Kumar, K. S.; Lee, J. H.; LeRose, J. J.; Liyanage, N.; Long, E.; McNulty, D.; Margaziotis, D. J.; Meddi, F.; Meekins, D. G.; Mercado, L.; Meziani, Z.-E.; Michaels, R.; Mihovilovic, M.; Muangma, N.; Myers, K. E.; Nanda, S.; Narayan, A.; Nelyubin, V.; Nuruzzaman; Oh, Y.; Parno, D.; Paschke, K. D.; Phillips, S. K.; Qian, X.; Qiang, Y.; Quinn, B.; Rakhman, A.; Reimer, P. E.; Rider, K.; Riordan, S.; Roche, J.; Rubin, J.; Russo, G.; Saenboonruang, K.; Saha, A.; Sawatzky, B.; Shahinyan, A.; Silwal, R.; Sirca, S.; Souder, P. A.; Suleiman, R.; Sulkosky, V.; Sutera, C. M.; Tobias, W. A.; Urciuoli, G. M.; Waidyawansa, B.; Wojtsekhowski, B.; Ye, L.; Zhao, B.; Zheng, X.

    2013-08-01

    We report on parity-violating asymmetries in the nucleon resonance region measured using inclusive inelastic scattering of 5-6 GeV longitudinally polarized electrons off an unpolarized deuterium target. These results are the first parity-violating asymmetry data in the resonance region beyond the Δ(1232). They provide a verification of quark-hadron duality—the equivalence of the quark- and hadron-based pictures of the nucleon—at the (10-15)% level in this electroweak observable, which is dominated by contributions from the nucleon electroweak γZ interference structure functions. In addition, the results provide constraints on nucleon resonance models relevant for calculating background corrections to elastic parity-violating electron scattering measurements.

  13. Nucleon-deuteron scattering using the adiabatic projection method

    NASA Astrophysics Data System (ADS)

    Elhatisari, Serdar; Lee, Dean; Meißner, Ulf-G.; Rupak, Gautam

    2016-06-01

    In this paper we discuss the adiabatic projection method, a general framework for scattering and reaction calculations on the lattice. We also introduce several new techniques developed to study nucleus-nucleus scattering and reactions on the lattice. We present technical details of the method for large-scale problems. To estimate the systematic errors of the calculations we consider simple two-particle scattering on the lattice. Then we benchmark the accuracy and efficiency of the numerical methods by applying these to calculate fermion-dimer scattering in lattice effective field theory with and without a long-range Coulomb potential. The fermion-dimer calculations correspond to neutron-deuteron and proton-deuteron scattering in the spin-quartet channel at leading order in the pionless effective field theory.

  14. Supersymmetry-generated jost functions and nucleon–nucleon scattering phase shifts

    SciTech Connect

    Bhoi, J. Laha, U.

    2015-10-15

    By exploiting the supersymmetry-inspired factorization method higher partial wave Jost solutions and functions for nuclear Hulthen potential are constructed from the knowledge of the ground state wave function. As a case study the nucleon–nucleon scattering phase shifts are computed for partial waves ℓ = 0, 1, and 2.

  15. Partial-wave analysis of all nucleon-nucleon scattering data below 350 MeV

    SciTech Connect

    Stoks, V.G.J.; Klomp, R.A.M.; Rentmeester, M.C.M.; de Swart, J.J. )

    1993-08-01

    We present a multienergy partial-wave analysis of all [ital NN] scattering data below [ital T][sub lab]=350 MeV, published in a regular physics journal between 1955 and 1992. After careful examination, our final database consists of 1787 [ital pp] and 2514 [ital np] scattering data. Our fit to these data results in [chi][sup 2]/[ital N][sub df]=1.08, with [ital N][sub df]=3945 the total number of degrees of freedom. All phase shifts and mixing parameters can be determined accurately.

  16. Ultra-High Energy Neutrino-Nucleon Scattering and Parton Distributions at Small x

    SciTech Connect

    Henley, Ernest M.; Jalilian-Marian, Jamal

    2006-11-17

    The cross section for ultra-high energy neutrino-nucleon scattering is very sensitive to the parton distributions at very small values of Bjorken x (x {<=} 10-4). We numerically investigate the effects of modifying the behavior of the gluon distribution function at very small x in the DGLAP evolution equation. We then use the Color Glass Condensate formalism to calculate the neutrino-nucleon cross section at ultra-high energies and compare the result with those based on modification of DGLAP evolution equation.

  17. Model-independent determination of the axial mass parameter in quasielastic neutrino-nucleon scattering

    SciTech Connect

    Bhattacharya, Bhubanjyoti; Hill, Richard J.; Paz, Gil

    2011-10-01

    Quasielastic neutrino-nucleon scattering is a basic signal process for neutrino oscillation studies. At accelerator energies, the corresponding cross section is subject to significant uncertainty due to the poorly constrained axial-vector form factor of the nucleon. A model-independent description of the axial-vector form factor is presented. Data from the MiniBooNE experiment for quasielastic neutrino scattering on {sup 12}C are analyzed under the assumption of a definite nuclear model. The value of the axial mass parameter, m{sub A}=0.85{sub -0.07}{sup +0.22}{+-}0.09 GeV, is found to differ significantly from extractions based on traditional form factor models. Implications for future neutrino scattering and pion electroproduction measurements are discussed.

  18. A relativistic meson-exchange model of pion-nucleon scattering

    SciTech Connect

    Lee, T.S.H.; Hung, C.T.; Yang, S.N.

    1995-08-01

    Pion-nucleon scattering is investigated using the Kadshevsky three-dimensional reduction of the Bethe-Salpeter equation. The resulting potential includes the direct and crossed N and {Delta} terms, and the t-channel {sigma}- and {rho}-exchange terms. The nucleon-pole condition is imposed to define the renormalization of the nucleon mass and the {pi}NN coupling constant. A mixture of the scalar and vector {sigma}{pi}{pi} couplings is introduced to simulate the broad width of the s-wave correlated two-pion exchange mechanism. Good descriptions of the {pi}N phase shifts up to 400 MeV have been obtained in all S- and P-waves. The off-shell behavior for our model differs significantly from that obtained using different reductions. A paper describing our results was published.

  19. Measurement of the Strange Quark Contribution to Nucleon Structure Through Parity-Violating Electron Scattering

    SciTech Connect

    Ellis, Colleen

    2010-01-01

    The G0 backward angle experiment, completed in Hall C of the Thomas Jefferson National Accelerator Facility (TJNAF), measured parity-violating asymmetries in elastic electron-proton and quasielastic electron-deuteron scattering at Q2 = 0.22 and 0.63 (GeV/c)2. The asymmetries are sensitive to strange quark contributions to currents in the nucleon and the nucleon axial-vector current. The results indicate strange quark contributions of ≤ 10% of the charge and magnetic nucleon form factors at these four-momentum transfers. This was also the first measurement of the anapole moment effects in the axial-vector current at these four-momentum transfers.

  20. Directional Antineutrino Detection

    NASA Astrophysics Data System (ADS)

    Safdi, Benjamin R.; Suerfu, Burkhant

    2015-02-01

    We propose the first event-by-event directional antineutrino detector using inverse beta decay (IBD) interactions on hydrogen, with potential applications including monitoring for nuclear nonproliferation, spatially mapping geoneutrinos, characterizing the diffuse supernova neutrino background and searching for new physics in the neutrino sector. The detector consists of adjacent and separated target and capture scintillator planes. IBD events take place in the target layers, which are thin enough to allow the neutrons to escape without scattering elastically. The neutrons are detected in the thicker boron-loaded capture layers. The location of the IBD event and the momentum of the positron are determined by tracking the positron's trajectory through the detector. Our design is a straightforward modification of existing antineutrino detectors; a prototype could be built with existing technology.

  1. Directional antineutrino detection.

    PubMed

    Safdi, Benjamin R; Suerfu, Burkhant

    2015-02-20

    We propose the first event-by-event directional antineutrino detector using inverse beta decay (IBD) interactions on hydrogen, with potential applications including monitoring for nuclear nonproliferation, spatially mapping geoneutrinos, characterizing the diffuse supernova neutrino background and searching for new physics in the neutrino sector. The detector consists of adjacent and separated target and capture scintillator planes. IBD events take place in the target layers, which are thin enough to allow the neutrons to escape without scattering elastically. The neutrons are detected in the thicker boron-loaded capture layers. The location of the IBD event and the momentum of the positron are determined by tracking the positron's trajectory through the detector. Our design is a straightforward modification of existing antineutrino detectors; a prototype could be built with existing technology. PMID:25763953

  2. Ab initio many-body calculations of nucleon scattering on ^16O

    NASA Astrophysics Data System (ADS)

    Navratil, Petr; Quaglioni, Sofia; Roth, Robert

    2008-10-01

    We develop a new ab initio many-body approachootnotetextS. Quaglioni and P. Navratil, arXiv:0804.1560. capable of describing simultaneously both bound and scattering states in light nuclei, by combining the resonating-group methodootnotetextY. C. Tang et al., Phys. Rep. 47, 167 (1978); K. Langanke and H. Friedrich, Advances in Nuclear Physics, Plenum, New York, 1987. with the ab initio no-core shell model (NCSM).ootnotetextP. Navratil, J. P. Vary, and B. R. Barrett, Phys. Rev. Lett. 84, 5728 (2000); Phys. Rev. C 62, 054311 (2000). In this way, we complement a microscopic-cluster technique with the use of realistic interactions, and a microscopic and consistent description of the nucleon clusters, while preserving Pauli principle and translational symmetry. We will present results for low-energy nucleon scattering on ^16O and for A=17 bound states obtained using realistic nucleon-nucleon potentials. The ^16O wave functions are calculated within the importance-truncated NCSMootnotetextR. Roth and P. Navratil, Phys. Rev. Lett. 99, 092501 (2007). that allows the use of model spaces up to 18φ and ultimately enables to reach convergence of phase-shifts and other observables. Prepared by LLNL under Contract DE-AC52-07NA27344. Support from the U.S. DOE/SC/NP (Work Proposal No. SCW0498), and from the U. S. Department of Energy Grant DE-FC02-07ER41457 is acknowledged.

  3. Measurement of Muon Antineutrino Quasielastic Scattering on a Hydrocarbon Target at Eν~3.5 GeV

    SciTech Connect

    Fields, L.; Chvojka, J.; Aliaga, L.; Altinok, O.; Baldin, B.; Baumbaugh, A.; Bodek, A.; Boehnlein, D.; Boyd, S.; Bradford, R.; Brooks, W. K.; Budd, H.; Butkevich, A.; Martinez Caicedo, D. A.; Castromonte, C. M.; Christy, M. E.; Chung, H.; Clark, M.; da Motta, H.; Damiani, D. S.; Danko, I.; Datta, M.; Day, M.; DeMaat, R.; Devan, J.; Draeger, E.; Dytman, S. A.; Díaz, G. A.; Eberly, B.; Edmondson, D. A.; Felix, J.; Fitzpatrick, T.; Fiorentini, G. A.; Gago, A. M.; Gallagher, H.; George, C. A.; Gielata, J. A.; Gingu, C.; Gobbi, B.; Gran, R.; Grossman, N.; Hanson, J.; Harris, D. A.; Heaton, J.; Higuera, A.; Howley, I. J.; Hurtado, K.; Jerkins, M.; Kafka, T.; Kaisen, J.; Kanter, M. O.; Keppel, C. E.; Kilmer, J.; Kordosky, M.; Krajeski, A. H.; Kulagin, S. A.; Le, T.; Lee, H.; Leister, A. G.; Locke, G.; Maggi, G.; Maher, E.; Manly, S.; Mann, W. A.; Marshall, C. M.; McFarland, K. S.; McGivern, C. L.; McGowan, A. M.; Mislivec, A.; Morfín, J. G.; Mousseau, J.; Naples, D.; Nelson, J. K.; Niculescu, G.; Niculescu, I.; Ochoa, N.; O’Connor, C. D.; Olsen, J.; Osmanov, B.; Osta, J.; Palomino, J. L.; Paolone, V.; Park, J.; Patrick, C. E.; Perdue, G. N.; Peña, C.; Rakotondravohitra, L.; Ransome, R. D.; Ray, H.; Ren, L.; Rodrigues, P. A.; Rude, C.; Sassin, K. E.; Schellman, H.; Schmitz, D. W.; Schneider, R. M.; Schulte, E. C.; Simon, C.; Snider, F. D.; Snyder, M. C.; Sobczyk, J. T.; Solano Salinas, C. J.; Tagg, N.; Tan, W.; Tice, B. G.; Tzanakos, G.; Velásquez, J. P.; Walding, J.; Walton, T.; Wolcott, J.; Wolthuis, B. A.; Woodward, N.; Zavala, G.; Zeng, H. B.; Zhang, D.; Zhu, L. Y.; Ziemer, B. P.

    2013-07-11

    We have isolated ν¯μ charged-current quasielastic (QE) interactions occurring in the segmented scintillator tracking region of the MINERvA detector running in the NuMI neutrino beam at Fermilab. We measure the flux-averaged differential cross section, dσ/dQ², and compare to several theoretical models of QE scattering. Good agreement is obtained with a model where the nucleon axial mass, MA, is set to 0.99 GeV/c² but the nucleon vector form factors are modified to account for the observed enhancement, relative to the free nucleon case, of the cross section for the exchange of transversely polarized photons in electron-nucleus scattering. Our data at higher Q² favor this interpretation over an alternative in which the axial mass is increased.

  4. Single-spin asymmetries in inclusive deep inelastic scattering and multiparton correlations in the nucleon

    NASA Astrophysics Data System (ADS)

    Metz, A.; Pitonyak, D.; Schäfer, A.; Schlegel, M.; Vogelsang, W.; Zhou, J.

    2012-11-01

    Transverse single-spin asymmetries in inclusive deep inelastic lepton-nucleon scattering can be generated through multiphoton exchange between the leptonic and the hadronic part of the process. Here we consider the two-photon exchange and mainly focus on the transverse target spin asymmetry. In particular, we investigate the case where two photons couple to different quarks. Such a contribution involves a quark-photon-quark correlator in the nucleon, which has a (model-dependent) relation to the Efremov-Teryaev-Qiu-Sterman quark-gluon-quark correlator TF. Using different parametrizations for TF we compute the transverse target spin asymmetries for both a proton and a neutron target and compare the results to recent experimental data. In addition, potential implications for our general understanding of single-spin asymmetries in hard scattering processes are discussed.

  5. Generalized polarizabilities and the spin-averaged amplitude in virtual Compton scattering off the nucleon

    SciTech Connect

    Drechsel, D.; Knoechlein, G.; Metz, A.; Scherer, S.

    1997-01-01

    We discuss the low-energy behavior of the spin-averaged amplitude of virtual Compton scattering off a nucleon. Based on gauge invariance, Lorentz invariance, and the discrete symmetries, it is shown that to first order in the frequency of the final real photon only two generalized polarizabilities appear. Different low-energy expansion schemes are discussed and put into perspective. {copyright} {ital 1997} {ital The American Physical Society}

  6. Proton and antiproton production in deep inelastic muon-nucleon scattering at 280 GeV

    NASA Astrophysics Data System (ADS)

    Arneodo, M.; Arvidson, A.; Aubert, J. J.; Badelek, B.; Beaufays, J.; Bee, C. P.; Benchouk, C.; Berghoff, G.; Bird, I.; Blum, D.; Böhm, E.; de Bouard, X.; Brasse, F. W.; Braun, H.; Broll, C.; Brown, S.; Brück, H.; Calen, H.; Chima, J. S.; Ciborowski, J.; Clifft, R.; Coignet, G.; Combley, F.; Coughlan, J.; D'Agostini, G.; Dahlgren, S.; Dengler, F.; Derado, I.; Dreyer, T.; Drees, J.; Düren, M.; Eckardt, V.; Edwards, A.; Edwards, M.; Ernst, T.; Eszes, G.; Favier, J.; Ferrero, M. I.; Figiel, J.; Flauger, W.; Foster, J.; Gabathuler, E.; Gajewski, J.; Gamet, R.; Gayler, J.; Geddes, N.; Grafström, P.; Grard, F.; Haas, J.; Hagberg, E.; Hasert, F. J.; Hayman, P.; Heusse, P.; Jaffré, M.; Jacholkowska, A.; Janata, F.; Jansco, G.; Johnson, A. S.; Kabuss, E. M.; Kellner, G.; Korbel, V.; Krüger, A.; Krüger, J.; Kullander, S.; Landgraf, U.; Lanske, D.; Loken, J.; Long, K.; Maire, M.; Malecki, P.; Manz, A.; Maselli, S.; Mohr, W.; Montanet, F.; Montgomery, H. E.; Nagy, E.; Nassalski, J.; Norton, P. R.; Oakham, F. G.; Osborne, A. M.; Pascaud, C.; Pawlik, B.; Payre, P.; Peroni, C.; Peschel, H.; Pessard, H.; Pettingale, J.; Pietrzyk, B.; Poensgen, B.; Pötsch, M.; Renton, P.; Ribarics, P.; Rith, K.; Rondio, E.; Sandacz, A.; Scheer, M.; Schlagböhmer, A.; Schiemann, H.; Schmitz, N.; Schneegans, M.; Scholz, M.; Schouten, M.; Schröder, T.; Schultze, K.; Sloan, T.; Stier, H. E.; Studt, M.; Taylor, G. N.; Thénard, J. M.; Thompson, J. C.; de La Torre, A.; Toth, J.; Urban, L.; Wallucks, W.; Whalley, M.; Wheeler, S.; Williams, W. S. C.; Wimpenny, S. J.; Windmolders, R.; Wolf, G.

    1987-12-01

    New results on proton and antiproton production in the target and current fragmentation regions of high energy muon-nucleon scattering are presented. Proton and antiproton production is investigated as a function of Feynman x and rapidity. No significant difference is observed between production on hydrogen and deuterium targets. Correlations between pp,pbar p andbar pbar p pairs are analysed and the results are compared with the predictions of the Lund fragmentation model.

  7. Parity Violating Electron Scattering and Strangeness in the Nucleon

    SciTech Connect

    Maas, Frank E.

    2008-10-13

    A measurement of the weak form factor of the proton allows a flavor separation of the strangeness contribution to the electromagnetic form factors. The weak form factor is accessed experimentally by the measurement of a parity violating (PV) asymmetry in the scattering of polarized electrons on unpolarized protons. An extended experimental program to measure these parity violating asymmetries has been performed and is going on at different accelerators. After the first round of experiments allowing a separation of the strangeness form factors G{sub E}{sup s} and G{sub M}{sup s} at a Q{sup 2}-value of 0.1 (GeV/c){sup 2}, new, preliminary results have been achieved at 0.23 (GeV/c){sup 2}.

  8. Antineutrino Neutral Current Interactions in MiniBooNE

    SciTech Connect

    Dharmapalan, Ranjan

    2012-01-01

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

  9. Exact expressions and improved approximations for interaction rates of neutrinos with free nucleons in a high-temperature, high-density gas

    NASA Technical Reports Server (NTRS)

    Schinder, Paul J.

    1990-01-01

    The exact expressions needed in the neutrino transport equations for scattering of all three flavors of neutrinos and antineutrinos off free protons and neutrons, and for electron neutrino absorption on neutrons and electron antineutrino absorption on protons, are derived under the assumption that nucleons are noninteracting particles. The standard approximations even with corrections for degeneracy, are found to be poor fits to the exact results. Improved approximations are constructed which are adequate for nondegenerate nucleons for neutrino energies from 1 to 160 MeV and temperatures from 1 to 50 MeV.

  10. Pion-nucleon scattering in covariant baryon chiral perturbation theory with explicit Delta resonances

    NASA Astrophysics Data System (ADS)

    Yao, De-Liang; Siemens, D.; Bernard, V.; Epelbaum, E.; Gasparyan, A. M.; Gegelia, J.; Krebs, H.; Meißner, Ulf-G.

    2016-05-01

    We present the results of a third order calculation of the pion-nucleon scattering amplitude in a chiral effective field theory with pions, nucleons and delta resonances as explicit degrees of freedom. We work in a manifestly Lorentz invariant formulation of baryon chiral perturbation theory using dimensional regularization and the extended on-mass-shell renormalization scheme. In the delta resonance sector, the on mass-shell renormalization is realized as a complex-mass scheme. By fitting the low-energy constants of the effective Lagrangian to the S- and P -partial waves a satisfactory description of the phase shifts from the analysis of the Roy-Steiner equations is obtained. We predict the phase shifts for the D and F waves and compare them with the results of the analysis of the George Washington University group. The threshold parameters are calculated both in the delta-less and delta-full cases. Based on the determined low-energy constants, we discuss the pion-nucleon sigma term. Additionally, in order to determine the strangeness content of the nucleon, we calculate the octet baryon masses in the presence of decuplet resonances up to next-to-next-to-leading order in SU(3) baryon chiral perturbation theory. The octet baryon sigma terms are predicted as a byproduct of this calculation.

  11. Ab initio many-body calculations of nucleon-4He scattering with three-nucleon forces

    SciTech Connect

    Hupin, Guillaume; Langhammer, Joachim; Navratil, Petr; Quaglioni, Sofia; Calci, Angelo; Roth, Robert

    2013-11-27

    We extend the ab initio no-core shell model/resonating-group method to include three-nucleon (3N) interactions for the description of nucleon-nucleus collisions. We outline the formalism, give algebraic expressions for the 3N-force integration kernels, and discuss computational aspects of two alternative implementations. The extended theoretical framework is then applied to nucleon-4He elastic scattering using similarity-renormalization-group (SRG)-evolved nucleon-nucleon plus 3N potentials derived from chiral effective field theory. We analyze the convergence properties of the calculated phase shifts and explore their dependence upon the SRG evolution parameter. We include up to six excited states of the 4He target and find significant effects from the inclusion of the chiral 3N force, e.g., it enhances the spin-orbit splitting between the 3/2 and 1/2 resonances and leads to an improved agreement with the phase shifts obtained from an accurate R-matrix analysis of the five-nucleon experimental data. As a result, we find remarkably good agreement with measured differential cross sections at various energies below the d+3H threshold, while analyzing powers manifest larger deviations from experiment for certain energies and angles.

  12. Mechanism of pion production in {alpha}p scattering at 1 GeV/nucleon

    SciTech Connect

    Alkhazov, G. D.; Prokofiev, A. N. Smirnov, I. B.; Strokovsky, E. A.

    2012-09-15

    An analysis of the experimental data on one-pion and two-pion production in the p({alpha}, {alpha} Prime )X reaction studied in a semi-exclusive experiment at an energy of E{sub {alpha}} = 4.2 GeV has been performed. The obtained results demonstrate that the inelastic {alpha}-particle scattering on the proton at the energy of the experiment proceeds either through excitation and decay of the {Delta} resonance in the projectile {alpha} particle, or through excitation in the target proton of the Roper resonance, which decays into a nucleon and a pion, or a nucleon and a {sigma} meson-a system of two pions in the isospin I = 0, S-wave state.

  13. Virtual compton scattering at low energy and the generalized polarizabilities of the nucleon

    SciTech Connect

    Helene Fonvieille

    2003-10-01

    We present a particular kind of (e, e' p) experiments, which has opened a new field of investigation of nucleon structure in the last ten years. The exclusive photon electroproduction process p(e, e' p){gamma} is used to study Virtual Compton Scattering (VCS) off the proton: {gamma}*p {yields} {gamma}p. In the low energy domain, this process gives access to new observables called the Generalized Polarizabilities. They are fundamental properties of the nucleon, characterizing the deformation of its internal structure under an applied electromagnetic field. Dedicated experiments have been performed at MAMI, Jefferson Lab and MIT-Bates. This contribution summarizes the results obtained so far and future prospects in the field.

  14. Neutrino and Antineutrino Cross sections at MiniBooNE

    SciTech Connect

    Dharmapalan, Ranjan; /Alabama U.

    2011-10-01

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

  15. Elastic pion-nucleon scattering in chiral perturbation theory: A fresh look

    NASA Astrophysics Data System (ADS)

    Siemens, D.; Bernard, V.; Epelbaum, E.; Gasparyan, A.; Krebs, H.; Meißner, Ulf-G.

    2016-07-01

    Elastic pion-nucleon scattering is analyzed in the framework of chiral perturbation theory up to fourth order within the heavy-baryon expansion and a covariant approach based on an extended on-mass-shell renormalization scheme. We discuss in detail the renormalization of the various low-energy constants and provide explicit expressions for the relevant β functions and the finite subtractions of the power-counting breaking terms within the covariant formulation. To estimate the theoretical uncertainty from the truncation of the chiral expansion, we employ an approach which has been successfully applied in the most recent analysis of the nuclear forces. This allows us to reliably extract the relevant low-energy constants from the available scattering data at low energy. The obtained results provide clear evidence that the breakdown scale of the chiral expansion for this reaction is related to the Δ resonance. The explicit inclusion of the leading contributions of the Δ isobar is demonstrated to substantially increase the range of applicability of the effective field theory. The resulting predictions for the phase shifts are in an excellent agreement with the predictions from the recent Roy-Steiner-equation analysis of pion-nucleon scattering.

  16. High energy proton-proton elastic scattering at the Large Hadron Collider and nucleon structure

    NASA Astrophysics Data System (ADS)

    Luddy, Richard Joseph

    To gain insight into the structure of the nucleon, we pursue the development of the phenomenological model of Islam et al. (IIFS model) for high energy elastic pp and p¯p scattering. We determine the energy dependence of the parameters of the IIFS model using the available elastic differential cross section data from SPS Collider and Tevatron and the known asymptotic behavior of sigmatot (s) and rho(s) from dispersion relation calculations and more recent analyses of Cudell et al. (COMPETE Collaboration). Next, we incorporate a high energy elastic valence quark-quark scattering amplitude into the model based on BFKL pomeron to describe small impact parameter (large | t|) pp collisions. Finally, we predict the pp elastic differential cross section at the unprecedented c.m. energy of s = 14.0 TeV at the Large Hadron Collider (LHC). This prediction assumes crucial significance---because of an approved experiment at LHC: TOTal and Elastic Measurement (TOTEM). The TOTEM group plans to measure pp elastic dsigma/dt at 14.0 TeV all the way from momentum transfer |t| = 0 to |t| ≃ 10 GeV 2. Their measurement will stringently test not only the diffraction and o-exchange descriptions of the original IIFS model, but also the additional valence quark-quark scattering contribution that we find to be dominant for large |t|. Successful quantitative verification of the predicted dsigma/dt will mean that our picture of the nucleon with an outer cloud of qq¯ condensed ground state, an inner core of topological baryonic charge, and a still smaller core of massless valence quarks provides a realistic description of nucleon structure.

  17. Parity violation in nucleon-nucleus elastic scattering within a phenomenological single particle model

    NASA Astrophysics Data System (ADS)

    Avishai, Y.

    1983-08-01

    Using a phenomenological neutron-40Ca strong and weak potentials at low energy we calculate the asymmetry A in the total cross section between positive and negative incoming helicity states, the asymmetry I in the differential elastic cross sections, and the neutron spin rotation angle dφdz. In general, max |IA|>>1. Taking into account the relevant cross sections, it turns out that sometimes, measuring I (instead of A) can save a substantial amount of beam time. NUCLEAR REACTIONS Parity violation, asymmetries, neutron spin rotation, σ-->.p--> interactions, neutron-nucleus scattering, phenomenological weak and strong nucleon-nucleus optical potential.

  18. a Phenomenological Determination of the Pion-Nucleon Scattering Lengths from Pionic Hydrogen

    NASA Astrophysics Data System (ADS)

    Ericson, T. E. O.; Loiseau, B.; Wycech, S.

    A model independent expression for the electromagnetic corrections to a phenomenological hadronic pion-nucleon (πN) scattering length ah, extracted from pionic hydrogen, is obtained. In a non-relativistic approach and using an extended charge distribution, these corrections are derived up to terms of order α2 log α in the limit of a short-range hadronic interaction. We infer ahπ ^-p=0.0870(5)m-1π which gives for the πNN coupling through the GMO relation g2π ^± pn/(4π )=14.04(17).

  19. Strangeness S =-1 hyperon-nucleon scattering in covariant chiral effective field theory

    NASA Astrophysics Data System (ADS)

    Li, Kai-Wen; Ren, Xiu-Lei; Geng, Li-Sheng; Long, Bingwei

    2016-07-01

    Motivated by the successes of covariant baryon chiral perturbation theory in one-baryon systems and in heavy-light systems, we study relevance of relativistic effects in hyperon-nucleon interactions with strangeness S =-1 . In this exploratory work, we follow the covariant framework developed by Epelbaum and Gegelia to calculate the Y N scattering amplitude at leading order. By fitting the five low-energy constants to the experimental data, we find that the cutoff dependence is mitigated, compared with the heavy-baryon approach. Nevertheless, the description of the experimental data remains quantitatively similar at leading order.

  20. Longitudinal-Transverse Separation of Deep-Inelastic Scattering at Low Q² on Nucleons and Nuclei

    SciTech Connect

    Tvaskis, Vladas

    2004-12-09

    Since the early experiments at SLAC, which discovered the nucleon substructure and led to the development of the quark parton model, deep inelastic scattering (DIS) has been the most powerful tool to investigate the partonic substructure of the nucleon. After about 30 years of experiments with electron and muon beams the nucleon structure function F{sub 2}(x,Q{sup 2}) is known with high precision over about four orders of magnitude in x and Q{sup 2}. In the region of Q{sup 2} > 1 (GeV/c){sup 2} the results of the DIS measurements are interpreted in terms of partons (quarks and gluons). The theoretical framework is provided in this case by perturbative Quantum Chromo Dynamics (pQCD), which includes scaling violations, as described by the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) equations. The description starts to fail when Q{sup 2} becomes of the order of 1 (GeV/c){sup 2}, where non-perturbative effects (higher-twist effects), which are still not fully understood, become important (non-pQCD). The sensitivity for order-n twist effects increases with decreasing Q{sup 2}, since they include a factor 1/(Q{sup 2}{sup n}) (n {ge} 1).

  1. Nucleon-nucleon data

    SciTech Connect

    McNaughton, M.W.; Gulmez, E.; Whitten, C.A.

    1997-10-01

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). This work completes the determination of the nucleon-nucleon (NN) scattering amplitudes from 485 to 800 MeV. The data set is completed by the publication of two papers. These new data have a precision better than 1% and an absolute accuracy about 1%, which is generally an order of magnitude better than previous data. The NN data set is now complete and consistent. The set of spin-dependent NN-scattering amplitudes is now well determined up to 800 MeV.

  2. A Lane consistent optical model potential for nucleon scattering on actinide nuclei with extended coupling

    NASA Astrophysics Data System (ADS)

    Quesada, José Manuel; Capote, Roberto; Soukhovitski, Efrem S.; Chiba, Satoshi

    2016-03-01

    An extension for odd-A actinides of a previously derived dispersive coupledchannel optical model potential (OMP) for 238U and 232Th nuclei is presented. It is used to fit simultaneously all the available experimental databases including neutron strength functions for nucleon scattering on 232Th, 233,235,238U and 239Pu nuclei. Quasi-elastic (p,n) scattering data on 232Th and 238U to the isobaric analogue states of the target nucleus are also used to constrain the isovector part of the optical potential. For even-even (odd) actinides almost all low-lying collective levels below 1 MeV (0.5 MeV) of excitation energy are coupled. OMP parameters show a smooth energy dependence and energy independent geometry.

  3. Determination of the pion-nucleon coupling constant and scattering lengths

    NASA Astrophysics Data System (ADS)

    Ericson, T. E.; Loiseau, B.; Thomas, A. W.

    2002-07-01

    We critically evaluate the isovector Goldberger-Miyazawa-Oehme (GMO) sum rule for forward πN scattering using the recent precision measurements of π-p and π-d scattering lengths from pionic atoms. We deduce the charged-pion-nucleon coupling constant, with careful attention to systematic and statistical uncertainties. This determination gives, directly from data, g2c(GMO)/ 4π=14.11+/-0.05(statistical)+/-0.19(systematic) or f2c/4π=0.0783(11). This value is intermediate between that of indirect methods and the direct determination from backward np differential scattering cross sections. We also use the pionic atom data to deduce the coherent symmetric and antisymmetric sums of the pion-proton and pion-neutron scattering lengths with high precision, namely, (aπ-p+aπ-n)/2=[- 12+/-2(statistical)+/-8(systematic)]×10-4 m-1π and (aπ-p-aπ- n)/2=[895+/-3(statistical)+/-13 (systematic)]×10-4 m-1π. For the need of the present analysis, we improve the theoretical description of the pion-deuteron scattering length.

  4. Measurement of the Parity-Violating Asymmetries in Electron-Deuteron Scattering in the Nucleon Resonance Region

    DOE PAGESBeta

    Wang, Diancheng; Pan, Kai; Subedi, Ramesh R.; Deng, Xiaoyan

    2013-08-22

    We report on parity-violating asymmetries in the nucleon resonance region measured using 5 - 6 GeV longitudinally polarized electrons scattering off an unpolarized deuterium target. These results are the first parity-violating asymmetry data in the resonance region beyond the Δ(1232), and provide a verification of quark-hadron duality in the nucleon electroweak γ Z interference structure functions at the (10-15)% level. The results are of particular interest to models relevant for calculating the γ Z box-diagram corrections to elastic parity-violating electron scattering measurements.

  5. The Method of Unitary Clothing Transformations in Relativistic Quantum Field Theory: Recent Applications for the Description of Nucleon-Nucleon Scattering and Deuteron Properties

    NASA Astrophysics Data System (ADS)

    Shebeko, A.

    2013-12-01

    The clothing procedure, put forward in quantum field theory by Greenberg and Schweber, is applied for the description of nucleon-nucleon ( N- N) scattering below the pion production threshold and deuteron properties. We consider pseudoscalar ( π and η), vector ( ρ and ω) and scalar ( δ and σ) meson fields interacting with N and ones via the Yukawa-type couplings to introduce trial interactions between "bare" particles. The subsequent unitary clothing transformations (UCTs) are found to express the total Hamiltonian through new interaction operators that refer to particles with physical (observable) properties, the so-called clothed particles. The corresponding analytic expressions in momentum space are compared with the separate meson contributions to the one-boson-exchange potentials in the meson theory of nuclear forces. We will also show a worked example where the UCTs method is used in the framework of a gauge-independent field-theoretical treatment of electromagnetic interactions of deuterons (bound systems).

  6. Chiral Three-Nucleon Interactions in Light Nuclei, Neutron-α Scattering, and Neutron Matter

    NASA Astrophysics Data System (ADS)

    Lynn, J. E.; Tews, I.; Carlson, J.; Gandolfi, S.; Gezerlis, A.; Schmidt, K. E.; Schwenk, A.

    2016-02-01

    We present quantum Monte Carlo calculations of light nuclei, neutron-α scattering, and neutron matter using local two- and three-nucleon (3 N ) interactions derived from chiral effective field theory up to next-to-next-to-leading order (N2LO ). The two undetermined 3 N low-energy couplings are fit to the 4He binding energy and, for the first time, to the spin-orbit splitting in the neutron-α P -wave phase shifts. Furthermore, we investigate different choices of local 3 N -operator structures and find that chiral interactions at N2LO are able to simultaneously reproduce the properties of A =3 ,4 ,5 systems and of neutron matter, in contrast to commonly used phenomenological 3 N interactions.

  7. Virtual Compton Scattering at low energy and the generalized polarizabilities of the nucleon

    SciTech Connect

    Helene Fonvieille

    2003-05-01

    Virtual Compton Scattering (VCS) {gamma}*p {yields} {gamma}p at low CM energy gives access to the Generalized Polarizabilities of the nucleon. These observables generalize the concept of electromagnetic polarizabilities to the case of a virtual photon. Dedicated VCS experiments have been performed at MAMI, Jefferson Lab and MIT-Bates. The experimental status is reviewed, including analysis methods and physics results. The measurement of absolute (ep {yields} ep{gamma}) cross sections allows the extraction of the two unpolarized VCS structure functions P{sub LL}-P{sub TT}/{epsilon} and P{sub LT}, which are combinations of the Generalized Polarizabilities of the proton. Future prospects in the field of VCS at low energy are also presented.

  8. Deeply Virtual Compton Scattering on nucleons and nuclei in generalized vector meson dominance model

    SciTech Connect

    Vadim Guzey; Klaus Goeke; Marat Siddikov

    2008-02-01

    We consider Deeply Virtual Compton Scattering (DVCS) on nucleons and nuclei in the framework of generalized vector meson dominance (GVMD) model. We demonstrate that the GVMD model provides a good description of the HERA data on the dependence of the proton DVCS cross section on $Q^2$, $W$ (at $Q^2=4$ GeV$^2$) and $t$. At $Q^2 = 8$ GeV$^2$, the soft $W$-behavior of the GVMD model somewhat underestimates the $W$-dependence of the DVCS cross section due to the hard contribution not present in the GVMD model. We estimate $1/Q^2$ power-suppressed corrections to the DVCS amplitude and the DVCS cross section and find them large. We also make predictions for the nuclear DVCS amplitude and cross section in the kinematics of the future Electron-Ion Collider. We predict significant nuclear shadowing, which matches well predictions of the leading-twist nuclear shadowing in DIS on nuclei.

  9. Strangeness production in deep inelastic muon nucleon scattering at 280 GeV

    NASA Astrophysics Data System (ADS)

    Arneodo, M.; Arvidson, A.; Aubert, J. J.; Badelek, B.; Beaufays, J.; Bee, C. P.; Benchouk, C.; Berghoff, G.; Bird, I.; Blum, D.; Böhm, E.; de Bouard, X.; Brasse, F. W.; Braun, H.; Broll, C.; Brown, S.; Brück, H.; Calen, H.; Chima, J. S.; Ciborowski, J.; Clifft, R.; Coignet, G.; Combley, F.; Coughlan, J.; D'Agostini, G.; Dahlgren, S.; Dengler, F.; Derado, I.; Dreyer, T.; Drees, J.; Düren, M.; Eckhardt, V.; Edwards, A.; Edwards, M.; Ernst, T.; Eszes, G.; Favier, J.; Ferrero, M. I.; Figiel, J.; Flauger, W.; Foster, J.; Gabathuler, E.; Gajewski, J.; Gamet, R.; Gayler, J.; Geddes, N.; Grafström, P.; Grard, F.; Haas, J.; Hagberg, E.; Hasert, F. J.; Hayman, P.; Heusse, P.; Jaffré, M.; Jacholkowska, A.; Janata, F.; Jancso, G.; Johnson, A. S.; Kabuss, E. M.; Kellner, G.; Korbel, V.; Krüger, J.; Kullander, S.; Landgraf, U.; Lanske, D.; Loken, J.; Long, K.; Maire, M.; Malecki, P.; Manz, A.; Maselli, S.; Mohr, W.; Montanet, F.; Montgomery, H. E.; Nagy, E.; Nassalski, J.; Norton, P. R.; Oakham, F. G.; Osborne, A. M.; Pascaud, C.; Pawlik, B.; Payre, P.; Peroni, C.; Peschel, H.; Pessard, H.; Pettingale, J.; Pietrzyk, B.; Pönsgen, B.; Pötsch, M.; Renton, P.; Ribarics, P.; Rith, K.; Rondio, E.; Sandacz, A.; Scheer, M.; Schlagböhmer, A.; Schiemann, H.; Schmifz, N.; Schneegans, M.; Scholz, M.; Schröder, T.; Schouten, M.; Schultze, K.; Sloan, T.; Stier, H. E.; Studt, M.; Taylor, G. N.; Thénard, J. M.; Thompson, J. C.; de La Torre, A.; Toth, J.; Urban, L.; Wallucks, W.; Whalley, M.; Wheeler, S.; Williams, W. S. C.; Wimpenny, S. J.; Windmolders, R.

    1987-09-01

    The production of strange particles has been studied in a 280 GeV muon nucleon scattering experiment with acceptance and particle identification over a large kinematical range. The data show that at large values of x Bj the interactions take place mostly on a u valence quark in agreement with the basic quarkparton model predictions. This feature results in a strong forward-backward asymmetry in the distribution of strangeness along the rapidity axis. The data are compatible with a strange to non-strange quark suppression factor of ≈0.3 and with a strong suppression of strange diquarks. The distributions of K + K - pairs show that the two kaons are preferentially produced at neighbouring values of rapidity.

  10. Pion-nucleon scattering in the Skyrme model and the P-wave Born amplitudes

    NASA Astrophysics Data System (ADS)

    Hayashi, A.; Saito, S.; Uehara, M.

    1991-03-01

    We treat fluctuating pion fields around a rotating Skyrmion by means of Dirac's quantization method. The rotational collective motion of the Skyrmion is described by collective coordinates, and conventional gauge-fixing conditions are imposed. Taking into account all the relevant terms at the tree level appearing in the Hamiltonian, we show that pion-nucleon scattering amplitudes exhibit the P-wave Born amplitudes attributed to the Yukawa coupling of order √Nc , which is consistent with the prediction of chiral symmetry such as the Adler-Weisberger relation. This resolves the difficulty that the Skyrme model predicts a wrong Nc dependence for the coupling of order N-3/2c.

  11. Chiral representation of the πN scattering amplitude and the pion-nucleon sigma term

    NASA Astrophysics Data System (ADS)

    Alarcón, J. M.; Camalich, J. Martin; Oller, J. A.

    2012-03-01

    We present a novel analysis of the πN scattering amplitude in Lorentz covariant baryon chiral perturbation theory renormalized in the extended-on-mass-shell scheme. This amplitude, valid up to O(p3) in the chiral expansion, systematically includes the effects of the Δ(1232) in the δ-counting, has the right analytic properties, and is renormalization-scale independent. This approach overcomes the limitations that previous chiral analyses of the πN scattering amplitude had, providing an accurate description of the partial wave phase shifts of the Karlsruhe-Helsinki and George-Washington groups up to energies just below the resonance region. We also study the solution of the Matsinos group which focuses on the parameterization of the data at low energies. Once the values of the low-energy constants are determined by adjusting the center-of-mass energy dependence of the amplitude to the scattering data, we obtain predictions on different observables. In particular, we extract an accurate value for the pion-nucleon sigma term, σπN. This allows us to avoid the usual method of extrapolation to the unphysical region of the amplitude. Our study indicates that the inclusion of modern meson-factory and pionic-atom data favors relatively large values of the sigma term. We report the value σπN=59(7)MeV and comment on implications that this result may have.

  12. Pion-Nucleon Scattering and Analysis from threshold to the N*(1440) Resonance Region

    NASA Astrophysics Data System (ADS)

    Sadler, Michael; Watson, Shon; Stahov, Jugoslav

    2008-10-01

    Many measurements for pion-nucleon scattering from threshold to the N*(1440) resonance region have been made since 1980, when the landmark Karlsruhe-Helsinki (KH) and Carnegie Mellon-Berkeley (CMB) partial wave analyses (PWA) were completed. These measurements consist of differential cross sections and analyzing powers for elastic scattering and charge exchange. Spin rotation parameters for elastic scattering in the momentum interval 0.4 -- 0.7 GeV/c have also been obtained. The program culminated with measurements of π-p -> Neutrals (charge exchange, multiple pi-zero final states, eta production, and inverse photoproduction) using the Crystal Ball at BNL. Resonance parameters for the N*(1440) in the Review of Particle Physics by the Particle Data Group have been obtained from the KH and CMB analyses. The 2006 edition also includes the analysis by George Washington University (GWU) ``for averages, fits, limits, etc.'', but the parameters were unchanged. An overview of the data will be presented along with comparisons to PWA.

  13. Single-inclusive production of hadrons and jets in lepton-nucleon scattering at NLO

    NASA Astrophysics Data System (ADS)

    Hinderer, Patriz; Schlegel, Marc; Vogelsang, Werner

    2015-07-01

    We present next-to-leading order (NLO) perturbative-QCD calculations of the cross sections for ℓN →h X and ℓN →jet X . The main feature of these processes is that the scattered lepton is not observed, so that the hard scale that makes them perturbative is set by the transverse momentum of the hadron or jet. Kinematically, the two processes thus become direct analogs of single-inclusive production in hadronic collisions which, as has been pointed out in the literature, makes them promising tools for exploring transverse spin phenomena in QCD when the incident nucleon is transversely polarized. We find that the NLO corrections are sizable for the spin-averaged cross section. We also investigate in how far the scattering is dominated by the exchange of almost real (Weizsäcker-Williams) photons. We present numerical estimates of the cross sections for present-day fixed target experiments and for a possible future electron-ion collider.

  14. Effect of the tensor part of Skyrme interaction on the description of elastic nucleon-nucleus scattering on the basis of the optical model

    SciTech Connect

    Kuprikov, V. I.; Pilipenko, V. V.

    2013-01-15

    A microscopic optical nucleon-nucleus potential constructed on the basis of calculating the mass operator for the single-particle Green's function with Skyrme nucleon-nucleon forces was used to study the effect of the tensor part of Skyrme forces on describing differential cross sections for elastic nucleon-nucleus scattering and the structure of nuclei within a self-consistent approach. It was shown that an increase in the tensor terms of nucleon-nucleon forces impaired the description of nucleon-nucleus scattering within the model being considered. The parameters of Skyrme forces were optimized on the basis of an analysis of cross sections for neutron-nucleus scattering, the properties of nuclear matter and the structure of nuclei being tested in doing this. This optimization led to nucleon-nucleon force versions where the tensor part was small or zero and which described satisfactorily the structure of nuclei and cross sections for elastic neutron and proton scattering on nuclei over a broad range of target mass numbers.

  15. Measurement of the antineutrino neutral-current elastic differential cross section

    DOE PAGESBeta

    Aguilar-Arevalo, A.  A.; Brown, B.  C.; Bugel, L.; Cheng, G.; Church, E.  D.; Conrad, J.  M.; Dharmapalan, R.; Djurcic, Z.; Finley, D.  A.; Ford, R.; et al

    2015-01-08

    We report the measurement of the flux-averaged antineutrino neutral current elastic scattering cross section (dσν-barN→ν-barN/dQ2) on CH2 by the MiniBooNE experiment using the largest sample of antineutrino neutral current elastic candidate events ever collected. The ratio of the antineutrino to neutrino neutral current elastic scattering cross sections and a ratio of the antineutrino neutral current elastic to antineutrino charged current quasi elastic cross sections are also presented.

  16. Measurement of the antineutrino neutral-current elastic differential cross section

    SciTech Connect

    Aguilar-Arevalo, A.  A.; Brown, B.  C.; Bugel, L.; Cheng, G.; Church, E.  D.; Conrad, J.  M.; Dharmapalan, R.; Djurcic, Z.; Finley, D.  A.; Ford, R.; Garcia, F.  G.; Garvey, G.  T.; Grange, J.; Huelsnitz, W.; Ignarra, C.; Imlay, R.; Johnson, R.  A.; Karagiorgi, G.; Katori, T.; Kobilarcik, T.; Louis, W.  C.; Mariani, C.; Marsh, W.; Mills, G.  B.; Mirabal, J.; Moore, C.  D.; Mousseau, J.; Nienaber, P.; Osmanov, B.; Pavlovic, Z.; Perevalov, D.; Polly, C.  C.; Ray, H.; Roe, B.  P.; Russell, A.  D.; Shaevitz, M.  H.; Spitz, J.; Stancu, I.; Tayloe, R.; Van de Water, R.  G.; Wascko, M.  O.; White, D.  H.; Wickremasinghe, D.  A.; Zeller, G.  P.; Zimmerman, E.  D.

    2015-01-08

    We report the measurement of the flux-averaged antineutrino neutral current elastic scattering cross section (dσν-barN→ν-barN/dQ2) on CH2 by the MiniBooNE experiment using the largest sample of antineutrino neutral current elastic candidate events ever collected. The ratio of the antineutrino to neutrino neutral current elastic scattering cross sections and a ratio of the antineutrino neutral current elastic to antineutrino charged current quasi elastic cross sections are also presented.

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

    NASA Astrophysics Data System (ADS)

    Wilkinson, Callum; McFarland, Kevin S.

    2016-07-01

    Nuclear effects on neutrino reactions are expected to be a significant complication in current and future neutrino oscillation experiments seeking precision measurements of neutrino flavor transitions. Calculations of these nuclear effects are hampered by a lack of experimental data comparing neutrino reactions on free nucleons to neutrino reactions on nuclei. We present results from a novel technique that compares neutrino and antineutrino charged current quasielastic scattering on hydrocarbons to extract a cross section ratio of antineutrino charged current elastic reactions on free protons to charged current quasielastic reactions on the protons bound in a carbon nucleus. This measurement of nuclear effects is compared to models.

  18. Electron and Muon production cross-sections in quasielastic ν(ν¯)-Nucleus scattering for Eν < 1GeV

    NASA Astrophysics Data System (ADS)

    Akbar, F.; Alam, M. Rafi; Athar, M. Sajjad; Chauhan, S.; Singh, S. K.; Zaidi, F.

    2015-10-01

    In this paper, we have studied (anti)neutrino induced charged current quasielastic (CCQE) scattering from some nuclear targets in the energy region of Eν < 1GeV. Our aim is to confront electron and muon production cross-sections relevant for νμ↔νe or ν¯μ↔ν¯e oscillation experiments. The effects due to lepton mass and its kinematic implications, radiative corrections, second class currents (SCCs) and uncertainties in the axial and pseudoscalar form factors are calculated for (anti)neutrino induced reaction cross-sections on free nucleon as well as the nucleons bound in a nucleus where nuclear medium effects influence the cross-section. For the nuclear medium effects, we have taken some versions of Fermi gas model (FGM) available in the literature. The results for (anti)neutrino-nucleus scattering cross-section per interacting nucleons are compared with the corresponding results in free nucleon case.

  19. Determination of sin/sup 2/theta/sub w/ by muon neutrino and anti-neutrino scattering by electrons

    SciTech Connect

    Abe, K.; Ahrens, L.A.; Amako, K.; Aronson, S.H.; Beier, E.W.; Callas, J.L.; Connolly, P.L.; Cutts, D.; Diwan, M.V.; Doughty, D.C.

    1988-01-01

    Total and differential cross sections for ..nu../sub ..mu../ and /bar /nu///sub ..mu../ elastic scattering by electrons were measured. The best value of sin/sup 2/theta/sub w/, obtained by fits to the differential distributions, was found to be sin/sup 2/theta/sub w/ = 0.195 +- 0.018 +- 0.013. 11 refs., 3 figs., 1 tab.

  20. Constraints on the virtual Compton scattering on the nucleon in a new dispersive formalism

    NASA Astrophysics Data System (ADS)

    Caprini, Irinel

    2016-04-01

    The dispersive representation of the virtual Compton forward scattering amplitude has been recently reexamined in connection with the evaluation of the Cottingham formula for the proton-neutron electromagnetic mass difference and the proton radius puzzle. The most difficult part of the analysis is related to one of the invariant amplitudes, denoted as T1(ν ,Q2), which requires a subtraction in the standard dispersion relation with respect to the energy ν at fixed photon momentum squared q2=-Q2. We propose an alternative dispersive framework, which implements analyticity and unitarity by combining the Cauchy integral relation at low and moderate energies with the modulus representation of the amplitude at high energies. Using techniques of functional analysis, we derive a necessary and sufficient condition for the consistency with analyticity of the subtraction function S1(Q2)=T1(0 ,Q2) , the cross sections measured at low and moderate energies and the Regge model assumed to be valid at high energies. From this condition we obtain model-independent constraints on the subtraction function, confronting them with the available information on nucleon magnetic polarizabilities and results reported recently in the literature. The formalism can be used also for testing the existence of a fixed pole at J =0 in the angular momentum plane, but more accurate data are necessary for a definite answer.

  1. Neutrino and Anti-neutrino Cross Sections at MiniBooNE

    SciTech Connect

    Dharmapalan, Ranjan

    2011-10-06

    The MiniBooNE experiment has reported a number of high statistics neutrino and anti-neutrino cross sections -among which are the charged current quasi-elastic (CCQE) and neutral current elastic (NCE) neutrino scattering on mineral oil (CH{sub 2}). Recently a study of the neutrino contamination of the anti-neutrino beam has concluded and the analysis of the anti-neutrino CCQE and NCE scattering is ongoing.

  2. Density and correlation integrals in deep-inelastic muon-nucleon scattering at 490 GeV

    NASA Astrophysics Data System (ADS)

    Adams, M. R.; Aïd, S.; Anthony, P. L.; Baker, M. D.; Bartlett, J.; Bhatti, A. A.; Botterweck, F.; Braun, H. M.; Busza, W.; Conrad, J. M.; Coutrakon, G.; Davisson, R.; Derado, I.; Dhawan, S. K.; Dougherty, W.; Dreyer, T.; Dziunikowska, K.; Eckardt, V.; Ecker, U.; Erdmann, M.; Eskreys, A.; Figiel, J.; Gebauer, H. J.; Geesaman, D. F.; Gilman, R.; Green, M. C.; Haas, J.; Halliwell, C.; Hanlon, J.; Hantke, D.; Hughes, V. W.; Jackson, H. E.; Jaffe, D. E.; Jancso, G.; Jansen, D. M.; Kadija, K.; Kaufman, S.; Kennedy, R. D.; Kirk, T.; Kobrak, H. G. E.; Krzywdzinski, S.; Kunori, S.; Lord, J. J.; Lubatti, H. J.; McLeod, D.; Magill, S.; Malecki, P.; Manz, A.; Melanson, H.; Michael, D. G.; Mohr, W.; Montgomery, H. E.; Morfin, J. G.; Nickerson, R. B.; O'Day, S.; Olkiewicz, K.; Osborne, L.; Papavassiliou, V.; Pawlik, B.; Pipkin, F. M.; Ramberg, E. J.; Röser, A.; Ryan, J. J.; Salgado, C. W.; Salvarani, A.; Schellman, H.; Schmitt, M.; Schmitz, N.; Schüler, K. P.; Seyerlein, H. J.; Skuja, A.; Snow, G. A.; Söldner-Rembold, S.; Steinberg, P. H.; Stier, H. E.; Stopa, P.; Swanson, R. A.; Talaga, R.; Tentindo-Repond, S.; Trost, H.-J.; Venkataramania, H.; Wilhelm, M.; Wilkes, J.; Wilson, Richard; Wittek, W.; Wolbers, S. A.; Zhao, T.; Fermilab E665 Collaboration

    1994-09-01

    Results on density integrals Fq( Q2) and correlation integrals Kq( Q2) are presented for the first time in muon-nucleon scattering at ∼ 490 GeV, using data from the E665 experiment at the Tevatron of Fermilab. A clear rise of the Fq integrals with decreasing size of the phase-space cells (“intermittency”) is observed for pairs and triplets of negative hadrons whereas the effect is much weaker for mixed charge combinations. From these findings it is concluded that the observed intermittency signal is mainly caused by Bose-Einstein interference. Furthermore, no energy ( W) dependence of F2( Q2) is observed within the W range of the E665 experiment. Finally, the third-order correlation integrals K3( Q2) are found to be significantly different from zero which implies the presence of genuine three-particle correlations in muon-nucleon interactions.

  3. Extended-soft-core baryon-baryon model. I. Nucleon-nucleon scattering with the ESC04 interaction

    SciTech Connect

    Rijken, Th.A.

    2006-04-15

    The NN results are presented from the extended-soft-core (ESC) interactions. They consist of local and nonlocal potentials due to (i) one-boson-exchanges (OBE), which are the members of nonets of pseudoscalar, vector, scalar, and axial mesons (ii) diffractive exchanges (iii) two-pseudoscalar exchanges (PS-PS), and (iv) meson-pair exchanges (MPE). We describe a fit to the pp and np data for 0{<=}T{sub lab}{<=}350 MeV, having a typical {chi}{sup 2}/N{sub data}=1.155. Here, we used {approx}20 quasi-free physical parameters, which are coupling constants and cutoff masses. A remarkable feature of the couplings is that we were able to require them to follow rather closely the pattern predicted by the {sup 3}P{sub 0} quark-pair-creation (QPC) model. As a result the 11 OBE couplings are rather constrained, i.e., quasi free. Also, the deuteron binding energy and the several NN scattering lengths are fitted.

  4. Photon emission in neutral current interactions with nucleons and nuclei

    SciTech Connect

    Alvarez-Ruso, L.; Nieves, J.; Wang, E.

    2015-05-15

    We report on our study of photon emission induced by E{sub ν} ∼ 1 GeV (anti)neutrino neutral current interactions with nucleons and nuclei. This process is an important background for ν{sub e} appearance oscillation experiments. At the relevant energies, the reaction is dominated by the excitation of the Δ(1232) resonance but there are also non-resonant contributions that, close to threshold, are fully determined by the effective chiral Lagrangian of strong interactions. We have obtained differential and integrated cross section for the (anti)neutrino-nucleon scattering and compare them with previous results. Furthermore, we have extended the model to nuclear targets taking into account Fermi motion, Pauli blocking and the in-medium modifications of the Δ properties. This study is important in order to reduce systematic effects in neutrino oscillation experiments.

  5. Probing Novel Properties of Nucleons and Nuclei via Parity Violating Electron Scattering

    SciTech Connect

    Mercado, Luis

    2012-05-01

    This thesis reports on two experiments conducted by the HAPPEx (Hall A Proton Parity Experiment) collaboration at the Thomas Jefferson National Accelerator Facility. For both, the weak neutral current interaction (WNC, mediated by the Z0 boson) is used to probe novel properties of hadronic targets. The WNC interaction amplitude is extracted by measuring the parity-violating asymmetry in the elastic scattering of longitudinally polarized electrons o unpolarized target hadrons. HAPPEx-III, conducted in the Fall of 2009, used a liquid hydrogen target at a momentum transfer of Q2 = 0.62 GeV2. The measured asymmetry was used to set new constraints on the contribution of strange quark form factors (GsE,M ) to the nucleon electromagnetic form factors. A value of APV = -23.803±} 0.778 (stat)± 0.359 (syst) ppm resulted in GsE + 0.517GsM = 0.003± 0.010 (stat)± 0.004 (syst)± 0.009 (FF). PREx, conducted in the Spring of 2010, used a polarized electron beam on a 208Pb target at a momentum transfer of Q2 = 0.009 GeV2. This parity-violating asymmetry can be used to obtain a clean measurement of the root-mean-square radius of the neutrons in the 208Pb nucleus. The Z0 boson couples mainly to neutrons; the neutron weak charge is much larger than that of the proton. The value of this asymmetry is at the sub-ppm level and has a projected experimental fractional precision of 3%. We will describe the accelerator setup used to set controls on helicity-correlated beam asymmetries and the analysis methods for finding the raw asymmetry for HAPPEx-III. We will also discuss in some detail the preparations to meet the experimental challenges associated with measuring such a small asymmetry with the degree of precision required for PREx.

  6. Three-body break-up in deuteron-deuteron scattering at 65 MeV/nucleon

    SciTech Connect

    Ramazani-Moghaddam-Arani, A.; Amir-Ahmadi, H. R.; Biegun, A.; Joulaeizadeh, L.; Kalantar-Nayestanaki, N.; Mardanpour, H.; Messchendorp, J. G.; Moeini, H.; Shende, S. V.; Bacher, A. D.; Bailey, C. D.; Stephenson, E. J.; Eslami-Kalantari, M.; Gasparic, I.; Kistryn, St.; Sworst, R.; Kozela, A.; Micherdzinska, A. M.; Stephan, E.

    2011-02-15

    In an experiment with a 65 MeV/nucleon polarized deuteron beam on a liquid-deuterium target at Kernfysisch Versneller Instituut, several multibody final states in deuteron-deuteron scattering were identified. For these measurements, a unique and advanced detection system, called the Big Instrument for Nuclear-polarization Analysis, was utilized. We demonstrate the feasibility of measuring vector and tensor polarization observables of the deuteron break-up reaction leading to a three-body final state. The polarization observables were determined with high precision in a nearly background-free experiment. The analysis procedure and some results are presented.

  7. Parity-Violating Electron Scattering from {sup 4}He and the Strange Electric Form Factor of the Nucleon

    SciTech Connect

    Aniol, K.A.; Margaziotis, D.J.; Armstrong, D.S.; Averett, T.; Finn, J.M.; Holmstrom, T.; Kelleher, A.; Moffit, B.; Sulkosky, V.; Benaoum, H.; Holmes, R.; Souder, P.A.; Bertin, P.Y.; Ferdi, C.

    2006-01-20

    We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from {sup 4}He at an average scattering angle <{theta}{sub lab}>=5.7 deg. and a four-momentum transfer Q{sup 2}=0.091 GeV{sup 2}. From these data, for the first time, the strange electric form factor of the nucleon G{sub E}{sup s} can be isolated. The measured asymmetry of A{sub PV}=(6.72{+-}0.84{sub (stat)}{+-}0.21{sub (syst)})x10{sup -6} yields a value of G{sub E}{sup s}=-0.038{+-}0.042{sub (stat)}{+-}0.010{sub (syst)}, consistent with zero.

  8. Parity-Violating Electron Scattering from {sup 4}He and the Strange Electric Form Factor of the Nucleon

    SciTech Connect

    Aniol, Konrad; Armstrong, David; Averett, Todd; Benaoum, Hachemi; Bertin, Pierre; Burtin, Etienne; Cahoon, Jason; Cates, Gordon; Chang, C; Chao, Yu-Chiu; Chen, Jian-Ping; Choi, Seonho; Chudakov, Eugene; Craver, Brandon; Cusanno, Francesco; Decowski, Piotr; Deepa, Deepa; Ferdi, Catherine; Feuerbach, Robert; Finn, John; Frullani, Salvatore; Fuoti, Kirsten; Garibaldi, Franco; Gilman, Ronald; Glamazdin, Oleksandr; Gorbenko, V; Grames, Joseph; Hansknecht, John; Higinbotham, Douglas; Holmes, Richard; Holmstrom, Timothy; Humensky, Thomas; Ibrahim, Hassan; Jager, Cornelis De; Jiang, Xiaodong; Kaufman, Lisa; Kelleher, Aidan; Kolarkar, Ameya; Kowalski, Stanley; Kumar, Krishna; Lambert, Daniel; Laviolette, Peter; LeRose, John; Lhuillier, David; Liyanage, Nilanga; Margaziotis, Demetrius; Mazouz, Malek; McCormick, Kathy; Meekins, David; Meziani, Zein-Eddine; Michaels, Robert; Moffit, Bryan; Monaghan, Peter; Camacho, Carlos Munoz; Nanda, Sirish; Nelyubin, Vladimir; Neyret, Damien; Paschke, Kent; Poelker, Benard; Pomatsalyuk, Roman; Qiang, Yi; Reitz, Bodo; Roche, Julie; Saha, Arunava; Singh, Jaideep; Snyder, Ryan; Souder, Paul; Subedi, Ramesh; Suleiman, Riad; Sulkosky, Vincent; Tobias, William; Urciuoli, Guido; Vacheret, Antonin; Voutier, Eric; Wang, Kebin; Wilson, R; Wojtsekhowski, Bogdan; Zheng, Xiaochao

    2005-06-01

    We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from {sup 4}He at an average scattering angle {theta}{sub lab} = 5.7 degrees and a four-momentum transfer Q{sup 2} = 0.091 GeV{sup 2}. From these data, for the first time, the strange electric form factor of the nucleon G{sub E}{sup s} can be isolated. The measured asymmetry of A{sub PV} = 6.72 {+-} 0.84 (stat) {+-} 0.21 (syst) parts per million yields a value of G{sub E}{sup s} = -0.038 {+-} 0.042 (stat) {+-} 0.010 (syst), consistent with zero.

  9. Peripheral elastic and inelastic scattering of {sup 17,18}O on light targets at 12 MeV/nucleon

    SciTech Connect

    Carstoiu, F.; Al-Abdullah, T.; Gagliardi, C. A.; Trache, L.

    2015-02-24

    The elastic and inelastic scattering of {sup 17,18}O with light targets has been undertaken at 12 MeV/nucleon in order to determine the optical potentials needed for the transfer reaction {sup 13}C({sup 17}O,{sup 18}O){sup 12}C. Optical potentials in both incoming and outgoing channels have been determined in a single experiment. This transfer reaction was used to infer the direct capture rate to the {sup 17}F(p,γ){sup 18}Ne which is essential to estimate the production of {sup 18}F at stellar energies in ONe novae. We demonstrate the stability of the ANC method and OMP results using good quality elastic and inelastic scattering data with stable beams. The peripherality of our reaction is inferred from a semiclassical decomposition of the total scattering amplitude into barrier and internal barrier components. Comparison between elastic scattering of {sup 17}O, {sup 18}O and {sup 16}O projectiles is made.

  10. Timelike Compton Scattering off the nucleon: observables and experimental perspectives for JLab at 12 GeV

    NASA Astrophysics Data System (ADS)

    Boër, Marie

    2016-03-01

    Hard exclusive processes such as photoproduction or electroproduction of photon or meson off the nucleon provide access to the Generalized Parton Distributions (GPDs), in the regime where the scattering amplitude is factorized into a hard and a soft part. GPDs contain the correlation between the longitudinal momentum fraction and the transverse spatial densities of quarks and gluons in the nucleon. Timelike Compton Scattering (TCS) correspond to the reaction γN → γ*N → e+e-N, where the photon is scattered off a quark. It is measured through its interference with the associated Bethe-Heitler process, which has the same final state. TCS allows to access the GPDs and test their universality by comparison to the results obtained with the DVCS process (eN → eγN). Also, results obtained with TCS provide additional independent constrains to the GPDs parameterization. We will present the physical motivations for TCS, with our theoretical predictions for TCS observables and their dependencies. We calculated for JLab 12 GeV energies all the single and double beam and/or target polarization observables off the proton and off the neutron. We will also present the experimental perspectives for the next years at JLab. Two proposals were already accepted at JLab: in Hall B, with the CLAS12 spectrometer, in order to measure the unpolarized cross section and in Hall A, with the SoLID spectrometer, in order to measure the unpolarized cross section and the beam spin asymmetry at high intensity. A Letter Of Intent was also submitted in order to measure the transverse target spin asymmetries in Hall C. We will discuss the merits of this different experiments and present some of the expected results.

  11. Charged current antineutrino reactions from {sup 12}C at MiniBooNE energies

    SciTech Connect

    Athar, M. Sajjad; Ahmad, Shakeb; Singh, S. K.

    2007-05-01

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

  12. Radiative effects in scattering of polarized leptons by polarized nucleons and light nuclei

    SciTech Connect

    Igor Akushevich; A. Ilyichev; N. Shumeiko

    2001-07-01

    Recent developments in the field of radiative effects in polarized lepton-nuclear scattering are reviewed. The processes of inclusive, semi-inclusive, diffractive and elastic scattering are considered. The explicit formulae obtained within the covariant approach are discussed. FORTRAN codes POLRAD, RADGEN, HAPRAD, DIFFRAD and MASCARAD created on the basis of the formulae are briefly described. Applications for data analysis of the current experiments on lepton-nuclear scattering at CERN, DESY, SLAC and TJNAF are illustrated by numerical results.

  13. Dynamical Coupled-Channel Model of pi-N scattering in te W < 2 GeV Nucleon Resonane Region

    SciTech Connect

    Lee, T S.H.; Julia-diaz, B; Matsuyama, A; Sato, T

    2007-12-01

    As a first step to analyze the electromagnetic meson production reactions in the nucleon resonance region, the parameters of the hadronic interactions of a dynamical coupled-channel model, developed in {\\it Physics Reports 439, 193 (2007)}, are determined by fitting the empirical $\\pi N$ elastic scattering amplitudes of SAID up to 2 GeV. The channels included in the calculations are $\\pi N$, $\\eta N$ and $\\pi\\pi N$ which has $\\pi\\Delta$, $\\rho N$, and $\\sigma N$ resonant components. The non-resonant meson-baryon interactions of the model are derived from a set of Lagrangians by using a unitary transformation method. One or two bare excited nucleon states in each of $S$, $P$, $D$, and $F$ partial waves are included to generate the resonant amplitudes in the fits. The predicted total cross sections of $\\pi N$ reactions and $\\pi N\\rightarrow \\eta N$ reactions are in good agreement with the data. Applications of the constructed model in analyzing the electromagnetic meson production data as well as the future developments are discussed.

  14. Production of neutral strange particles in muon-nucleon scattering at 490 GeV

    NASA Astrophysics Data System (ADS)

    Adams, M. R.; Aderholz, M.; Aïd, S.; Anthony, P. L.; Baker, M. D.; Bartlett, J.; Bhatti, A. A.; Braun, H. M.; Busza, W.; Conrad, J. M.; Coutrakon, G.; Davisson, R.; Derado, I.; Dhawan, S. K.; Dougherty, W.; Dreyer, T.; Dziunikowska, K.; Eckardt, V.; Ecker, U.; Erdmann, M.; Eskreys, A.; Figiel, J.; Gebauer, H. J.; Geesaman, D. F.; Gilman, R.; Green, M. C.; Haas, J.; Halliwell, C.; Hanlon, J.; Hantke, D.; Hughes, V. W.; Jackson, H. E.; Jaffe, D. E.; Jancso, G.; Jansen, D. M.; Kadija, K.; Kaufman, S.; Kennedy, R. D.; Kirk, T.; Kobrak, H. G. E.; Krzywdzinski, S.; Kunori, S.; Lord, J. J.; Lubatti, H. J.; McLeod, D.; Magill, S.; Malecki, P.; Manz, A.; Melanson, H.; Michael, D. G.; Mohr, W.; Montgomery, H. E.; Morfin, J. G.; Nickerson, R. B.; O'Day, S.; Olkiewicz, K.; Osborne, L.; Papavassiliou, V.; Pawlik, B.; Pipkin, F. M.; Ramberg, E. J.; Röser, A.; Ryan, J. J.; Salgado, C. W.; Salvarani, A.; Schellman, H.; Schmitt, M.; Schmitz, N.; Schüler, K. P.; Seyerlein, H. J.; Skuja, A.; Snow, G. A.; Söldner-Rembold, S.; Steinberg, P. H.; Stier, H. E.; Stopa, P.; Swanson, R. A.; Talaga, R.; Tentindo-Repond, S.; Trost, H. J.; Venkataramania, H.; Wilhelm, M.; Wilkes, J.; Wilson, R.; Wittek, W.; Wolbers, S. A.; Zhao, T.

    1994-12-01

    The production of K 0, Λ andbar Λ particles is studied in the E665 muon-nucleon experiment at Fermilab. The average multiplicities and squared transverse momenta are measured as a function of x F and W 2. Most features of the data can be well described by the Lund model. Within this model, the data on the K0/π± ratios and on the average K 0 multiplicity in the forward region favor a strangeness suppression factor s/u in the fragmentation process near 0.20. Clear evidence for QCD effects is seen in the average squared transverse momentum of K 0 and Λ particles.

  15. The two-photon exchange contribution to elastic electron-nucleon scattering at large momentum transfer

    SciTech Connect

    Andrei V. Afanasev; Stanley J. Brodsky; Carl E. Carlson; Yu-Chun Chen; Marc Vanderhaeghen

    2005-01-01

    We estimate the two-photon exchange contribution to elastic electron-proton scattering at large momentum transfer by using a quark-parton representation of virtual Compton scattering. We thus can relate the two-photon exchange amplitude to the generalized parton distributions which also enter in other wide angle scattering processes. We find that the interference of one- and two-photon exchange contribution is able to substantially resolve the difference between electric form factor measurements from Rosenbluth and polarization transfer experiments.

  16. In-medium effect with muon-neutrino and anti-muon-neutrino quasi-elastic scattering from 12C nucleons

    NASA Astrophysics Data System (ADS)

    Cheoun, Myung-Ki; Kim, K. S.; Kim, Hungchong; So, W. Y.; Maruyama, Tomoyuki; Kajino, Toshitaka

    2015-04-01

    We investigated the in-medium effect by density-dependent axial and weak-vector form factors on muon-neutrino ({{ν }μ }) and anti-muon-neutrino ({{\\bar{ν }}μ }) scattering in the quasi-elastic (QE) region from nucleons (N*) bound in a nucleus or immersed in a nuclear medium via neutral current (NC) and charged current (CC). For the density-dependent form factors, we exploited a quark-meson-coupling (QMC) model. We found that the {{ν }μ }({{\\bar{ν }}μ })-{{N}*} scattering cross sections via NC in the QE region usually decrease with an increased medium density, while those using CC were increased. However, their rate of change was sensitive to the four-momentum transfer given to a bound nucleon through scattering. We compared these results obtained by the elementary process corrected by the in-medium effect to the BNL and MiniBooNE data, which measured {{ν }μ } scattering cross sections per nucleon through {{ν }μ } - 12C scattering in 12C composite targets. The incident energy range was 550 \\lt {{E}ν }\\lt 3000 MeV. We increased the energy up to 100 GeV to compare our results to the NOMAD experimental data. In order to study the density effects on a nucleon embedded in 12C, we exploited the QMC form factors evaluated at ρ =0.5{{ρ }o}, where the normal density {{ρ }o}˜ 0.15 f{{m}-3}. The strangeness contributions in NC scattering are also incorporated into the form factors for comparison with experimental data. Our numerical results show that most of the experimental data can be explained in a satisfactory manner by the density-dependent elementary process, but there are some remaining deviations resulting from the nuclear structure, particularly in the low and high momentum-transfer regions.

  17. Model independent radiative corrections in processes of polarized electron-nucleon elastic scattering

    SciTech Connect

    Igor Akushevich; Andrei Afanasev; Mykola Merenkov

    2001-12-01

    The explicit formulae for radiative correction (RC) calculation for elastic ep-scattering is presented. Two typical measurements of polarization observables such as beam-target asymmetry or recoil proton polarization, are considered. Possibilities to take into account realistic experimental acceptances are discussed. The Fortran code MASCARAD for providing the RC procedure is presented. Numerical analysis is done for kinematical conditions of TJNAF.

  18. Model independent radiative corrections in processes of polarized electron-nucleon elastic scattering

    NASA Astrophysics Data System (ADS)

    Afanasev, A.; Akushevich, I.; Merenkov, N.

    2001-12-01

    Explicit formulas for radiative correction (RC) calculations for elastic ep scattering are presented. Two typical measurements of polarization observables, such as beam-target asymmetry or recoil proton polarization, are considered. The possibilities of taking into account realistic experimental acceptances are discussed. The FORTRAN code MASCARAD for providing the RC procedure is presented. A numerical analysis is done for the kinematical conditions of CEBAF.

  19. Modeling single arm electron scattering and nucleon production from nuclei by GeV electrons

    SciTech Connect

    Lightbody J.W. Jr.; O'Connell, J.S.

    1988-05-01

    Nuclear reaction data for the doubly differential cross sections of inelastic electron scattering and of electronucleon and electropion production are parametrized by analytic models of the major reaction mechanisms. Predictive FORTRAN codes for the yields of reaction products have been developed for all nuclei interacting with electrons and bremsstrahlung beams in the energy range 0.5--5 GeV. Comparison with a variety of electromagnetic reaction data is shown.

  20. Nucleon scattering from very light nuclei: Intermediate energy expansions for transition potentials and breakup processes

    SciTech Connect

    Elster, C.; Gloeckle, W.

    1997-03-01

    Transition potentials for elastic p-d scattering and the coupled processes p+{sup 3}He {r_arrow} p+{sup 3}He and n+{sup 3}He {r_arrow} d+d are derived in the Faddeev-Yakubovsky framework with special emphasis on leading order terms, which are expected to be valid at intermediate energies. In addition, equations for the fragmentations {sup 3}He(p,ppp)n and {sup 3}He(p,pp)d are derived within the same framework. Again leading order terms for intermediate energies are considered. {copyright} {ital 1997} {ital The American Physical Society}

  1. A phenomenological study of photon production in low energy neutrino nucleon scattering

    SciTech Connect

    Jenkins, James P; Goldman, Terry J

    2009-01-01

    Low energy photon production is an important background to many current and future precision neutrino experiments. We present a phenomenological study of t-channel radiative corrections to neutral current neutrino nucleus scattering. After introducing the relevant processes and phenomenological coupling constants, we will explore the derived energy and angular distributions as well as total cross-section predictions along with their estimated uncertainties. This is supplemented throughout with comments on possible experimental signatures and implications. We conclude with a general discussion of the analysis in the context of complimentary methodologies. This is based on a talk presented at the DPF 2009 meeting in Detroit MI.

  2. Neutron-proton effective mass splitting in neutron-rich matter at normal density from analyzing nucleon-nucleus scattering data within an isospin dependent optical model

    NASA Astrophysics Data System (ADS)

    Li, Xiao-Hua; Guo, Wen-Jun; Li, Bao-An; Chen, Lie-Wen; Fattoyev, Farrukh J.; Newton, William G.

    2015-04-01

    The neutron-proton effective mass splitting in asymmetric nucleonic matter of isospin asymmetry δ and normal density is found to be mn-p* ≡ (mn* - mp*) / m = (0.41 ± 0.15) δ from analyzing globally 1088 sets of reaction and angular differential cross sections of proton elastic scattering on 130 targets with beam energies from 0.783 MeV to 200 MeV, and 1161 sets of data of neutron elastic scattering on 104 targets with beam energies from 0.05 MeV to 200 MeV within an isospin dependent non-relativistic optical potential model. It sets a useful reference for testing model predictions on the momentum dependence of the nucleon isovector potential necessary for understanding novel structures and reactions of rare isotopes.

  3. Short-Range Nucleon-Nucleon Correlations

    SciTech Connect

    Douglas Higinbotham

    2011-10-01

    Valence-shell nucleon knock-out experiments, such as 12C(e,e'p)11B, measure less strength then is predicted by independent particle shell model calculations. The theoretical solution to this problem is to include the correlations between the nucleons in the nucleus in the calculations. Motivated by these results, many electron scattering experiments have tried to directly observe these correlations in order to gain new insight into the short-range part of the nucleon-nucleon potential. Unfortunately, many competing mechanisms can cause the same observable final-state as an initial-state correlation, making truly isolating the signal extremely challenging. This paper reviews the recent experimental evidence for short-range correlations, as well as explores the possibility that such correlations are responsible for the EMC effect in the 0.3 < xB < 0.7 deep inelastic scattering ratios.

  4. Axial structure of the nucleon

    SciTech Connect

    Veronique Bernard; Latifa Elouadrhiri; Ulf-G Meissner

    2002-01-01

    We review the current status of experimental and theoretical understanding of the axial nucleon structure at low and moderate energies. Topics considered include (quasi)elastic (anti)neutrino-nucleon scattering, charged pion electroproduction off nucleons and ordinary as well as radiative muon capture on the proton.

  5. Nucleon-nucleon interactions

    SciTech Connect

    Wiringa, R.B.

    1996-12-31

    Nucleon-nucleon interactions are at the heart of nuclear physics, bridging the gap between QCD and the effective interactions appropriate for the shell model. We discuss the current status of {ital NN} data sets, partial-wave analyses, and some of the issues that go into the construction of potential models. Our remarks are illustrated by reference to the Argonne {ital v}{sub 18} potential, one of a number of new potentials that fit elastic nucleon-nucleon data up to 350 MeV with a {Chi}{sup 2} per datum near 1. We also discuss the related issues of three-nucleon potentials, two-nucleon charge and current operators, and relativistic effects. We give some examples of calculations that can be made using these realistic descriptions of {ital NN} interactions. We conclude with some remarks on how our empirical knowledge of {ital NN} interactions may help constrain models at the quark level, and hence models of nucleon structure.

  6. [ital Q][sup 2] dependence of the average squared transverse energy of jets in deep-inelastic muon-nucleon scattering with comparison to perturbative QCD predictions

    SciTech Connect

    Adams, M.R.; Arndotied, S.; Anthony, P.L.; Baker, M.D.; Bartlett, J.; Bhatti, A.A.; Braun, H.M.; Busza, W.; Conrad, J.M.; Coutrakon, G.; Davisson, R.; Derado, I.; Dhawan, S.K.; Dougherty, W.; Dreyer, T.; Dziunikowska, K.; Eckardt, V.; Ecker, U.; Erdmann, M.; Eskreys, A.; Figiel, J.; Gebauer, H.J.; Geesaman, D.F.; Gilman, R.; Green, M.C.; Haas, J.; Halliwell, C.; Hanlon, J.; Hantke, D.; Hughes, V.W.; Jackson, H.E.; Jaffe, D.E.; Jancso, G.; Jansen, D.M.; Kaufman, S.; Kennedy, R.D.; Kirk, T.; Kobrak, H.G.E.; Krzywdzinski, S.; Kunori, S.; Lord, J.J.; Lubatti, H.J.; McLeod, D.; Magill, S.; Malecki, P.; Manz, A.; Melanson, H.; Michael, D.G.; Mohr, W.; Montgomery, H.E.; Morfin, J.G.; Nickerson, R.B.; O'Day, S.; Olkiewicz, K.; Osborne, L.; Papavassiliou, V.; Pawlik, B.; Pipkin, F.M.; Ramberg, E.J.; Roeser, A.; Ryan, J.J.; Salgado, C.W.; Salvarani, A.; Schellman, H.; Schmitt, M.; Schmitz, N.; Schueler, K.P.; Skuja, A.; Snow, G.A.; Soeldner-Rembold, S.; Steinberg, P.H.; Stier, H.E.; Stopa, P.; S

    1994-01-24

    The average squared transverse energy of jets in deep-inelastic muon-nucleon scattering is measured as a function of the momentum transfer squared ([ital Q][sup 2]), in the range 3[lt][ital Q][sup 2][lt]25 GeV[sup 2]. Perturbative QCD predicts that the average squared parton transverse energy will depend upon the strong coupling constant ([alpha][sub [ital S

  7. Microscopic model analysis of {sup 11}Li+p elastic scattering at 62, 68.4, and 75 MeV/nucleon

    SciTech Connect

    Hassan, M. Y. M.; Farag, M. Y. H.; Esmael, E. H.; Maridi, H. M.

    2009-01-15

    {sup 11}Li+p elastic scattering data at three energies, 62, 68.4, and 75 MeV/nucleon, are analyzed with density-dependent M3Y and KH effective nucleon-nucleon (NN) interactions in the framework of the single folding model. The parameters of the density-dependent term are adjusted to fulfill saturation of nuclear matter. The optical potentials (OP's) and cross sections are calculated using four model densities of {sup 11}Li, G (one-parameter Gaussian), GG (Gaussian-Gaussian), GO (Gaussian- oscillator), and the COSMA (cluster orbital shell model approximation). Comparative studies are performed for real, imaginary, and spin-orbit potentials with the phenomenological and microscopic forms. The microscopic volume and surface imaginary potentials are constructed from both the renormalized folded potentials and their derivatives. The sensitivity of the differential cross section to the four densities is tested. It is found that the {sup 11}Li+p elastic scattering cross sections depend strongly upon the behavior of the corresponding potentials. The GG and GO densities obtained from analyzing the data, using Glauber multiple scattering theory at high energies, give good results at energies below 100 MeV/nucleon in the framework of the folding model. The OP's calculated in the microscopic form using few parameters give good agreement with the data. Thus, it is not necessary to introduce a large number of arbitrary fitting parameters as done in the phenomenological and semimicroscopic OP's. The KH effective interaction successfully describes {sup 11}Li+p elastic scattering as the popular M3Y interaction. The obtained results of the reaction cross section are in good agreement with previous calculations.

  8. Stopping power of neutrinos and antineutrinos in polymers

    NASA Technical Reports Server (NTRS)

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

    1985-01-01

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

  9. Stopping power of neutrinos and antineutrinos in polymers

    NASA Astrophysics Data System (ADS)

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

    1985-09-01

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

  10. Measurement of azimuthal hadron asymmetries in semi-inclusive deep inelastic scattering off unpolarised nucleons

    NASA Astrophysics Data System (ADS)

    Adolph, C.; Akhunzyanov, R.; Alexeev, M. G.; Alexandrov, Yu.; Alexeev, G. D.; Amoroso, A.; Andrieux, V.; Anosov, V.; Austregesilo, A.; Badełek, B.; Balestra, F.; Barth, J.; Baum, G.; Beck, R.; Bedfer, Y.; Berlin, A.; Bernhard, J.; Bertini, R.; Bicker, K.; Bieling, J.; Birsa, R.; Bisplinghoff, J.; Bodlak, M.; Boer, M.; Bordalo, P.; Bradamante, F.; Braun, C.; Bravar, A.; Bressan, A.; Büchele, M.; Burtin, E.; Capozza, L.; Chiosso, M.; Chung, S. U.; Cicuttin, A.; Crespo, M. L.; Curiel, Q.; Dalla Torre, S.; Dasgupta, S. S.; Dasgupta, S.; Denisov, O. Yu.; Donskov, S. V.; Doshita, N.; Duic, V.; Dünnweber, W.; Dziewiecki, M.; Efremov, A.; Elia, C.; Eversheim, P. D.; Eyrich, W.; Faessler, M.; Ferrero, A.; Filin, A.; Finger, M.; Finger, M.; Fischer, H.; Franco, C.; du Fresne von Hohenesche, N.; Friedrich, J. M.; Frolov, V.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O. P.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gnesi, I.; Gobbo, B.; Goertz, S.; Gorzellik, M.; Grabmüller, S.; Grasso, A.; Grube, B.; Guskov, A.; Guthörl, T.; Haas, F.; von Harrach, D.; Hahne, D.; Hashimoto, R.; Heinsius, F. H.; Herrmann, F.; Hinterberger, F.; Höppner, Ch.; Horikawa, N.; d'Hose, N.; Huber, S.; Ishimoto, S.; Ivanov, A.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jary, V.; Jasinski, P.; Joerg, P.; Joosten, R.; Kabuß, E.; Kang, D.; Ketzer, B.; Khaustov, G. V.; Khokhlov, Yu. A.; Kisselev, Yu.; Klein, F.; Klimaszewski, K.; Koivuniemi, J. H.; Kolosov, V. N.; Kondo, K.; Königsmann, K.; Konorov, I.; Konstantinov, V. F.; Kotzinian, A. M.; Kouznetsov, O.; Kral, Z.; Krämer, M.; Kroumchtein, Z. V.; Kuchinski, N.; Kunne, F.; Kurek, K.; Kurjata, R. P.; Lednev, A. A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Maggiora, A.; Magnon, A.; Makke, N.; Mallot, G. K.; Marchand, C.; Martin, A.; Marzec, J.; Matousek, J.; Matsuda, H.; Matsuda, T.; Meshcheryakov, G.; Meyer, W.; Michigami, T.; Mikhailov, Yu. V.; Miyachi, Y.; Nagaytsev, A.; Nagel, T.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V. I.; Novy, J.; Nowak, W.-D.; Nunes, A. S.; Orlov, I.; Olshevsky, A. G.; Ostrick, M.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Pesek, M.; Peshekhonov, D.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V. A.; Pretz, J.; Quaresma, M.; Quintans, C.; Ramos, S.; Reicherz, G.; Rocco, E.; Rodionov, V.; Rondio, E.; Rychter, A.; Rossiyskaya, N. S.; Ryabchikov, D. I.; Samoylenko, V. D.; Sandacz, A.; Sarkar, S.; Savin, I. A.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schlüter, T.; Schmidt, A.; Schmidt, K.; Schmieden, H.; Schönning, K.; Schopferer, S.; Schott, M.; Shevchenko, O. Yu.; Silva, L.; Sinha, L.; Sirtl, S.; Slunecka, M.; Sosio, S.; Sozzi, F.; Srnka, A.; Steiger, L.; Stolarski, M.; Sulc, M.; Sulej, R.; Suzuki, H.; Szableski, A.; Szameitat, T.; Sznajder, P.; Takekawa, S.; ter Wolbeek, J.; Tessaro, S.; Tessarotto, F.; Thibaud, F.; Uhl, S.; Uman, I.; Vandenbroucke, M.; Virius, M.; Vondra, J.; Wang, L.; Weisrock, T.; Wilfert, M.; Windmolders, R.; Wiślicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.

    2014-09-01

    Spin-averaged asymmetries in the azimuthal distributions of positive and negative hadrons produced in deep inelastic scattering were measured using the CERN SPS longitudinally polarised muon beam at 160 GeV/c and a 6LiD target. The amplitudes of the three azimuthal modulations cos⁡ϕh, cos⁡2ϕh and sin⁡ϕh were obtained binning the data separately in each of the relevant kinematic variables x, z or pTh and binning in a three-dimensional grid of these three variables. The amplitudes of the cos⁡ϕh and cos⁡2ϕh modulations show strong kinematic dependencies both for positive and negative hadrons.

  11. Reactor antineutrino experiments

    NASA Astrophysics Data System (ADS)

    Lu, Haoqi

    2014-05-01

    Neutrinos are elementary particles in the standard model of particle physics. There are three flavors of neutrinos that oscillate among themselves. Their oscillation can be described by a 3×3 unitary matrix, containing three mixing angles θ12, θ23, θ13, and one CP phase. Both θ12 and θ23 are known from previous experiments. θ13 was unknown just two years ago. The Daya Bay experiment gave the first definitive non-zero value in 2012. An improved measurement of the oscillation amplitude sin 22(θ 13) = 0.090+0.008-0.009 and the first direct measurement of the \\bar ν e mass-squared difference ∣ Δ m2ee∣ = (2.59+0.19-0.20)× 10-3 eV2 were obtained recently. The large value of θ13 boosts the next generation of reactor antineutrino experiments designed to determine the neutrino mass hierarchy, such as JUNO and RENO-50.

  12. Detection of Breeding Blankets Using Antineutrinos

    NASA Astrophysics Data System (ADS)

    Cogswell, Bernadette; Huber, Patrick

    2016-03-01

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

  13. Nucleon Electromagnetic Form Factors

    SciTech Connect

    Kees de Jager

    2004-08-01

    Although nucleons account for nearly all the visible mass in the universe, they have a complicated structure that is still incompletely understood. The first indication that nucleons have an internal structure, was the measurement of the proton magnetic moment by Frisch and Stern (1933) which revealed a large deviation from the value expected for a point-like Dirac particle. The investigation of the spatial structure of the nucleon, resulting in the first quantitative measurement of the proton charge radius, was initiated by the HEPL (Stanford) experiments in the 1950s, for which Hofstadter was awarded the 1961 Nobel prize. The first indication of a non-zero neutron charge distribution was obtained by scattering thermal neutrons off atomic electrons. The recent revival of its experimental study through the operational implementation of novel instrumentation has instigated a strong theoretical interest. Nucleon electro-magnetic form factors (EMFFs) are optimally studied through the exchange of a virtual photon, in elastic electron-nucleon scattering. The momentum transferred to the nucleon by the virtual photon can be selected to probe different scales of the nucleon, from integral properties such as the charge radius to scaling properties of its internal constituents. Polarization instrumentation, polarized beams and targets, and the measurement of the polarization of the recoiling nucleon have been essential in the accurate separation of the charge and magnetic form factors and in studies of the elusive neutron charge form factor.

  14. Reactor antineutrino experiments

    NASA Astrophysics Data System (ADS)

    Lu, Haoqi

    2014-09-01

    Neutrinos are elementary particles in the standard model of particle physics. There are three flavors of neutrinos that oscillate among themselves. Their oscillation can be described by a 3×3 unitary matrix, containing three mixing angles θ12, θ23, θ13, and one CP phase. Both θ12 and θ23 are known from previous experiments. θ13 was unknown just two years ago. The Daya Bay experiment gave the first definitive nonzero value in 2012. An improved measurement of the oscillation amplitude sin 22(θ 13) = 0.090+0.008-0.009 and the first direct measurement of the \\bar ν e mass-squared difference \\vertΔ m2ee\\vert\\big (2.59+0.19-0.20\\big )×10-3 eV2 were obtained recently. The large value of θ13 boosts the next generation of reactor antineutrino experiments designed to determine the neutrino mass hierarchy, such as JUNO and RENO-50.

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

    NASA Astrophysics Data System (ADS)

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

    2015-08-01

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

  16. Q2 dependence of the average squared transverse energy of jets in deep-inelastic muon-nucleon scattering with comparison to perturbative QCD predictions

    NASA Astrophysics Data System (ADS)

    Adams, M. R.; Arndotïd, S.; Anthony, P. L.; Baker, M. D.; Bartlett, J.; Bhatti, A. A.; Braun, H. M.; Busza, W.; Conrad, J. M.; Coutrakon, G.; Davisson, R.; Derado, I.; Dhawan, S. K.; Dougherty, W.; Dreyer, T.; Dziunikowska, K.; Eckardt, V.; Ecker, U.; Erdmann, M.; Eskreys, A.; Figiel, J.; Gebauer, H. J.; Geesaman, D. F.; Gilman, R.; Green, M. C.; Haas, J.; Halliwell, C.; Hanlon, J.; Hantke, D.; Hughes, V. W.; Jackson, H. E.; Jaffe, D. E.; Jancso, G.; Jansen, D. M.; Kaufman, S.; Kennedy, R. D.; Kirk, T.; Kobrak, H. G.; Krzywdzinski, S.; Kunori, S.; Lord, J. J.; Lubatti, H. J.; McLeod, D.; Magill, S.; Malecki, P.; Manz, A.; Melanson, H.; Michael, D. G.; Mohr, W.; Montgomery, H. E.; Morfin, J. G.; Nickerson, R. B.; O'day, S.; Olkiewicz, K.; Osborne, L.; Papavassiliou, V.; Pawlik, B.; Pipkin, F. M.; Ramberg, E. J.; Röser, A.; Ryan, J. J.; Salgado, C. W.; Salvarani, A.; Schellman, H.; Schmitt, M.; Schmitz, N.; Schüler, K. P.; Skuja, A.; Snow, G. A.; Söldner-Rembold, S.; Steinberg, P. H.; Stier, H. E.; Stopa, P.; Swanson, R. A.; Talaga, R.; Tentindo-Repond, S.; Trost, H.-J.; Venkataramania, H.; Wilhelm, M.; Wilkes, J.; Wilson, Richard; Wittek, W.; Wolbers, S. A.; Zhao, T.

    1994-01-01

    The average squared transverse energy of jets in deep-inelastic muon-nucleon scattering is measured as a function of the momentum transfer squared (Q2), in the range 3

  17. Nucleon elastic form factors

    SciTech Connect

    D. Day

    2007-03-01

    The nucleon form factors are still the subject of active investigation even after an experimental effort spanning 50 years. This is because they are of critical importance to our understanding of the electromagnetic properties of nuclei and provide a unique testing ground for QCD motivated models of nucleon structure. Progress in polarized beams, polarized targets and recoil polarimetry have allowed an important and precise set of data to be collected over the last decade. I will review the experimental status of elastic electron scattering from the nucleon along with an outlook for future progress.

  18. Elastic scattering and breakup effect analysis of {sup 11}Be+{sup 12}C at 38.4 MeV/nucleon

    SciTech Connect

    Hassan, M. Y. M.; Farag, M. Y. H.; Esmael, E. H.; Maridi, H. M.

    2009-06-15

    {sup 11}Be+{sup 12}C elastic-scattering data at 38.4 MeV/nucleon has been analyzed using the optical model. The optical potential is calculated in the framework of the double folding model using M3Y effective nucleon-nucleon interaction. Different models of {sup 11}Be density are tested and the model that does not include the halo structure gives poor fitting with data. The breakup effect is studied by introducing a complex dynamical polarization potential (DPP) that is added to the ''bare'' potential. The DPP is taken in different forms that have been obtained from simple phenomenological, semiclassical approximation, and microscopic methods. The simple phenomenological DPP is related to the semiclassical approximation method. The sensitivity of the differential and reaction cross sections to these polarization potentials is tested. The microscopic DPP that has been constructed from the derivative of the folding potential describes the breakup effect well. It gives an explicit justification for the long range of the polarization potential.

  19. Sea-Quark Flavor Asymmetry in the Nucleon from a Relativistic Analysis of the Drell-Yan Scattering off Nuclei

    NASA Astrophysics Data System (ADS)

    Molochkov, Alexander

    The study presented in this paper shows that accounting for the relativistic structure of the deuteron allows to explain the ratio of the Drell-Yan pair production cross-sections at the low Bjorken x off the deuteron and the proton. Thus, the sea quark distributions in the nucleon should be studied with accounting for the effects of the relativistic structure of the deuteron. The suggested approach reduces theoretical uncertainty in extracting the ratio bar {u}/bar {d} from the data and it is important for the clarification of the nature of the sea quark asymmetry in the nucleon.

  20. Charm-Quark Production in Deep-Inelastic Neutrino Scattering at Next-to-Next-to-Leading Order in QCD

    NASA Astrophysics Data System (ADS)

    Berger, Edmond L.; Gao, Jun; Li, Chong Sheng; Liu, Ze Long; Zhu, Hua Xing

    2016-05-01

    We present a fully differential next-to-next-to-leading order calculation of charm-quark production in charged-current deep-inelastic scattering, with full charm-quark mass dependence. The next-to-next-to-leading order corrections in perturbative quantum chromodynamics are found to be comparable in size to the next-to-leading order corrections in certain kinematic regions. We compare our predictions with data on dimuon production in (anti)neutrino scattering from a heavy nucleus. Our results can be used to improve the extraction of the parton distribution function of a strange quark in the nucleon.

  1. Charm-Quark Production in Deep-Inelastic Neutrino Scattering at Next-to-Next-to-Leading Order in QCD.

    PubMed

    Berger, Edmond L; Gao, Jun; Li, Chong Sheng; Liu, Ze Long; Zhu, Hua Xing

    2016-05-27

    We present a fully differential next-to-next-to-leading order calculation of charm-quark production in charged-current deep-inelastic scattering, with full charm-quark mass dependence. The next-to-next-to-leading order corrections in perturbative quantum chromodynamics are found to be comparable in size to the next-to-leading order corrections in certain kinematic regions. We compare our predictions with data on dimuon production in (anti)neutrino scattering from a heavy nucleus. Our results can be used to improve the extraction of the parton distribution function of a strange quark in the nucleon. PMID:27284650

  2. Measurement of parton distributions of strange quarks in the nucleon from charged-kaon production in deep-inelastic scattering on the dueteron.

    SciTech Connect

    Airapetian, A.; Akopov, N.; Akopov, Z.; Andrus, A.; Aschenauer, E. C.; Jackson, H. E.; Reimer, P. E.; HERMES Collaboration; Physics; Univ. of Michigan; Yerevan Physics Inst.; Univ. of Illinois; DESY Lab.

    2008-01-01

    The momentum and helicity density distributions of the strange quark sea in the nucleon are obtained in leading order from charged-kaon production in deep-inelastic scattering on the deuteron. The distributions are extracted from spin-averaged K{sup {+-}} multiplicities, and from K{sup {+-}} and inclusive double-spin asymmetries for scattering of polarized positrons by a polarized deuterium target. The shape of the momentum distribution is softer than that of the average of the {bar u} and {bar d} quarks. In the region of measurement 0.02 < x < 0.6 and Q{sup 2} > 1.0 GeV{sup 2}, the helicity distribution is zero within experimental uncertainties.

  3. Few-nucleon systems with state-of-the-art chiral nucleon-nucleon forces

    NASA Astrophysics Data System (ADS)

    Binder, S.; Calci, A.; Epelbaum, E.; Furnstahl, R. J.; Golak, J.; Hebeler, K.; Kamada, H.; Krebs, H.; Langhammer, J.; Liebig, S.; Maris, P.; Meißner, Ulf-G.; Minossi, D.; Nogga, A.; Potter, H.; Roth, R.; Skibiński, R.; Topolnicki, K.; Vary, J. P.; Witała, H.; Lenpic Collaboration

    2016-04-01

    We apply improved nucleon-nucleon potentials up to fifth order in chiral effective field theory, along with a new analysis of the theoretical truncation errors to study nucleon-deuteron (N d ) scattering and selected low-energy observables in 3H,4He , and 6Li. Calculations beyond second order differ from experiment well outside the range of quantified uncertainties, providing truly unambiguous evidence for missing three-nucleon forces within the employed framework. The sizes of the required three-nucleon-force contributions agree well with expectations based on Weinberg's power counting. We identify the energy range in elastic N d scattering best suited to study three-nucleon-force effects and estimate the achievable accuracy of theoretical predictions for various observables.

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

    SciTech Connect

    Devan, Joshua D.

    2015-01-01

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

  5. Few-Nucleon Systems

    NASA Astrophysics Data System (ADS)

    Kievsky, A.

    2005-04-01

    Recent advances in the theoretical description of few-nucleon systems are reported. This research activity has been performed under the Italian project FISICA TEORICA DEL NUCLEO E DEI SISTEMI A MOLTI CORPI. Bound and scattering states as well as specific reactions are analyzed in connection with the current experimental activity.

  6. Precision spectroscopy with reactor antineutrinos

    NASA Astrophysics Data System (ADS)

    Huber, Patrick; Schwetz, Thomas

    2004-09-01

    In this work we present an accurate parameterization of the antineutrino flux produced by the isotopes 235U, 239Pu, and 241Pu in nuclear reactors. We determine the coefficients of this parameterization, as well as their covariance matrix, by performing a fit to spectra inferred from experimentally measured beta spectra. Subsequently we show that flux shape uncertainties play only a minor role in the KamLAND experiment, however, we find that future reactor-neutrino experiments to measure the mixing angle θ13 are sensitive to the fine details of the reactor-neutrino spectra. Finally, we investigate the possibility to determine the isotopic composition in nuclear reactors through an antineutrino measurement. We find that with a three month exposure of a 1ton detector the isotope fractions and the thermal reactor power can be determined at a few percent accuracy, which may open the possibility of an application for safeguard or nonproliferation objectives.

  7. Results on the Spin-Dependent Scattering of Weakly Interacting Massive Particles on Nucleons from the Run 3 Data of the LUX Experiment

    NASA Astrophysics Data System (ADS)

    Akerib, D. S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Beltrame, P.; Bernard, E. P.; Bernstein, A.; Biesiadzinski, T. P.; Boulton, E. M.; Bradley, A.; Bramante, R.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Chapman, J. J.; Chiller, A. A.; Chiller, C.; Currie, A.; Cutter, J. E.; Davison, T. J. R.; de Viveiros, L.; Dobi, A.; Dobson, J. E. Y.; Druszkiewicz, E.; Edwards, B. N.; Faham, C. H.; Fiorucci, S.; Gaitskell, R. J.; Gehman, V. M.; Ghag, C.; Gibson, K. R.; Gilchriese, M. G. D.; Hall, C. R.; Hanhardt, M.; Haselschwardt, S. J.; Hertel, S. A.; Hogan, D. P.; Horn, M.; Huang, D. Q.; Ignarra, C. M.; Ihm, M.; Jacobsen, R. G.; Ji, W.; Kazkaz, K.; Khaitan, D.; Knoche, R.; Larsen, N. A.; Lee, C.; Lenardo, B. G.; Lesko, K. T.; Lindote, A.; Lopes, M. I.; Malling, D. C.; Manalaysay, A.; Mannino, R. L.; Marzioni, M. F.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J. A.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H. N.; Neves, F.; O'Sullivan, K.; Oliver-Mallory, K. C.; Ott, R. A.; Palladino, K. J.; Pangilinan, M.; Pease, E. K.; Phelps, P.; Reichhart, L.; Rhyne, C.; Shaw, S.; Shutt, T. A.; Silva, C.; Solovov, V. N.; Sorensen, P.; Stephenson, S.; Sumner, T. J.; Szydagis, M.; Taylor, D. J.; Taylor, W.; Tennyson, B. P.; Terman, P. A.; Tiedt, D. R.; To, W. H.; Tripathi, M.; Tvrznikova, L.; Uvarov, S.; Verbus, J. R.; Webb, R. C.; White, J. T.; Whitis, T. J.; Witherell, M. S.; Wolfs, F. L. H.; Yazdani, K.; Young, S. K.; Zhang, C.; LUX Collaboration

    2016-04-01

    We present experimental constraints on the spin-dependent WIMP (weakly interacting massive particle)-nucleon elastic cross sections from LUX data acquired in 2013. LUX is a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility (Lead, South Dakota), which is designed to observe the recoil signature of galactic WIMPs scattering from xenon nuclei. A profile likelihood ratio analysis of 1.4 ×104 kg day of fiducial exposure allows 90% C.L. upper limits to be set on the WIMP-neutron (WIMP-proton) cross section of σn=9.4 ×10-41 cm2 (σp=2.9 ×10-39 cm2 ) at 33 GeV /c2 . The spin-dependent WIMP-neutron limit is the most sensitive constraint to date.

  8. Determination of the gluon distribution function of the nucleon using energy-energy angular pattern in deep-inelastic muon-deuteron scattering

    NASA Astrophysics Data System (ADS)

    Adams, M. R.; Aïd, S.; Anthony, P. L.; Baker, M. D.; Bartlett, J.; Bhatti, A. A.; Braun, H. M.; Busza, W.; Carroll, T. J.; Conrad, J. M.; Coutrakon, G.; Davisson, R.; Derado, I.; Dhawan, S. K.; Dougherty, W.; Dreyer, T.; Dziunikowska, K.; Eckardt, V.; Ecker, U.; Erdmann, M.; Eskreys, A.; Figiel, J.; Gebauer, H. J.; Geesaman, D. F.; Gilman, R.; Green, M. C.; Haas, J.; Halliwell, C.; Hanlon, J.; Hantke, D.; Hughes, V. W.; Jackson, H. E.; Jancso, G.; Jansen, D. M.; Kaufman, S.; Kennedy, R. D.; Kirk, T.; Kobrak, H. G. E.; Krzywdzinski, S.; Kunori, S.; Lord, J. J.; Lubatti, H. J.; McLeod, D.; Magill, S.; Malecki, P.; Manz, A.; Melanson, H.; Michael, D. G.; Mohr, W.; Montgomery, H. E.; Morfin, J. G.; Nickerson, R. B.; O'Day, S.; Olkiewicz, K.; Osborne, L.; Papavassiliou, V.; Pawlik, B.; Pipkin, F. M.; Ramberg, E. J.; Röser, A.; Ryan, J. J.; Salgado, C. W.; Salvarani, A.; Schellman, H.; Schmitt, M.; Schmitz, N.; Schüler, K. P.; Seyerlein, H. J.; Skuja, A.; Snow, G. A.; Söldner-Rembold, S.; Steinberg, P. H.; Stier, H. E.; Stopa, P.; Swanson, R. A.; Talaga, R.; Tentindo-Repond, S.; Trost, H. J.; Venkataramania, H.; Wilhelm, M.; Wilkes, J.; Wilson, Richard; Wittek, W.; Wolbers, S. A.; Zhao, T.

    1996-03-01

    We have used the energy-energy angular pattern of hadrons in inelastic muon-deuteron scattering to study perturbative QCD effects and to extract the gluon distribution function ηG( η) of the nucleon, where η is the fractional momentum carried by the gluon. The data were taken with the E665 spectrometer using the Fermilab Tevatron muon beam with a mean beam energy of 490 GeV. We present ηG( η) for 0.005< η<0.05 and at an average Q 2 of 8 GeV2 using this new technique. We find that ηG( η) in this region can be described by ηG( η) α ηλ with λ=-0.87±0.09( stat.)±{0.37/0.32}( sys.). We compare our results to expectations from various parametrizations of the parton distribution function and also to results from HERA.

  9. Results on the Spin-Dependent Scattering of Weakly Interacting Massive Particles on Nucleons from the Run 3 Data of the LUX Experiment.

    PubMed

    Akerib, D S; Araújo, H M; Bai, X; Bailey, A J; Balajthy, J; Beltrame, P; Bernard, E P; Bernstein, A; Biesiadzinski, T P; Boulton, E M; Bradley, A; Bramante, R; Cahn, S B; Carmona-Benitez, M C; Chan, C; Chapman, J J; Chiller, A A; Chiller, C; Currie, A; Cutter, J E; Davison, T J R; de Viveiros, L; Dobi, A; Dobson, J E Y; Druszkiewicz, E; Edwards, B N; Faham, C H; Fiorucci, S; Gaitskell, R J; Gehman, V M; Ghag, C; Gibson, K R; Gilchriese, M G D; Hall, C R; Hanhardt, M; Haselschwardt, S J; Hertel, S A; Hogan, D P; Horn, M; Huang, D Q; Ignarra, C M; Ihm, M; Jacobsen, R G; Ji, W; Kazkaz, K; Khaitan, D; Knoche, R; Larsen, N A; Lee, C; Lenardo, B G; Lesko, K T; Lindote, A; Lopes, M I; Malling, D C; Manalaysay, A; Mannino, R L; Marzioni, M F; McKinsey, D N; Mei, D-M; Mock, J; Moongweluwan, M; Morad, J A; Murphy, A St J; Nehrkorn, C; Nelson, H N; Neves, F; O'Sullivan, K; Oliver-Mallory, K C; Ott, R A; Palladino, K J; Pangilinan, M; Pease, E K; Phelps, P; Reichhart, L; Rhyne, C; Shaw, S; Shutt, T A; Silva, C; Solovov, V N; Sorensen, P; Stephenson, S; Sumner, T J; Szydagis, M; Taylor, D J; Taylor, W; Tennyson, B P; Terman, P A; Tiedt, D R; To, W H; Tripathi, M; Tvrznikova, L; Uvarov, S; Verbus, J R; Webb, R C; White, J T; Whitis, T J; Witherell, M S; Wolfs, F L H; Yazdani, K; Young, S K; Zhang, C

    2016-04-22

    We present experimental constraints on the spin-dependent WIMP (weakly interacting massive particle)-nucleon elastic cross sections from LUX data acquired in 2013. LUX is a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility (Lead, South Dakota), which is designed to observe the recoil signature of galactic WIMPs scattering from xenon nuclei. A profile likelihood ratio analysis of 1.4×10^{4}  kg day of fiducial exposure allows 90% C.L. upper limits to be set on the WIMP-neutron (WIMP-proton) cross section of σ_{n}=9.4×10^{-41}  cm^{2} (σ_{p}=2.9×10^{-39}  cm^{2}) at 33  GeV/c^{2}. The spin-dependent WIMP-neutron limit is the most sensitive constraint to date. PMID:27152786

  10. Results on the spin-dependent scattering of weakly interacting massive particles on nucleons from the Run 3 Data of the LUX Experiment

    DOE PAGESBeta

    Akerib, D. S.

    2016-04-20

    Here, we present experimental constraints on the spin-dependent WIMP (weakly interacting massive particle)-nucleon elastic cross sections from LUX data acquired in 2013. LUX is a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility (Lead, South Dakota), which is designed to observe the recoil signature of galactic WIMPs scattering from xenon nuclei. A profile likelihood ratio analysis of 1.4 × 104 kg day of fiducial exposure allows 90% C.L. upper limits to be set on the WIMP-neutron (WIMP-proton) cross section of σn = 9.4 × 10–41 cm2 (σp = 2.9 × 10–39 cm2) at 33 GeV/c2. Themore » spin-dependent WIMP-neutron limit is the most sensitive constraint to date.« less

  11. Measurements of Polarization Transfers in Real Compton Scattering by a proton target at JLAB. A new source of information on the 3D shape of the nucleon

    SciTech Connect

    Fanelli, Cristiano V.

    2015-03-01

    In this thesis work, results of the analysis of the polarization transfers measured in real Compton scattering (RCS) by the Collaboration E07-002 at the Je fferson Lab Hall-C are presented. The data were collected at large scattering angle (theta_cm = 70deg) and with a polarized incident photon beam at an average energy of 3.8 GeV. Such a kind of experiments allows one to understand more deeply the reaction mechanism, that involves a real photon, by extracting both Compton form factors and Generalized Parton Distributions (GPDs) (also relevant for possibly shedding light on the total angular momentum of the nucleon). The obtained results for the longitudinal and transverse polarization transfers K_LL and K_LT, are of crucial importance, since they confirm unambiguously the disagreement between experimental data and pQCD prediction, as it was found in E99-114 experiment, and favor the Handbag mechanism. The E99-114 and E07-002 results can contribute to attract new interest on the great yield of the Compton scattering by a nucleon target, as demonstrated by the recent approval of an experimental proposal submitted to the Jefferson Lab PAC 42 for a Wide-angle Compton Scattering experiment, at 8 and 10 GeV Photon Energies. The new experiments approved to run with the updated 12 GeV electron beam at JLab, are characterized by much higher luminosities, and a new GEM tracker is under development to tackle the challenging backgrounds. Within this context, we present a new multistep tracking algorithm, based on (i) a Neural Network (NN) designed for a fast and efficient association of the hits measured by the GEM detector which allows the track identification, and (ii) the application of both a Kalman filter and Rauch-Tung-Striebel smoother to further improve the track reconstruction. The full procedure, i.e. NN and filtering, appears very promising, with high performances in terms of both association effciency and reconstruction accuracy, and these preliminary results will

  12. Weak production of strange particles off the nucleon

    SciTech Connect

    Alam, M. Rafi; Athar, M. Sajjad; Simo, I. Ruiz; Alvarez-Ruso, L.; Vacas, M. J. Vicente

    2015-05-15

    The strange particle production off the nucleon induced by neutrinos and antineutrinos is investigated at low and intermediate energies. We develop a microscopic model based on the SU(3) chiral Lagrangian. The studied mechanisms are the main source of single kaon production for (anti)neutrino energies up to 1.5 GeV. Using this model we have also studied the associated production of kaons and hyperons. The cross sections are large enough to be measured by experiments such as MINERνA, T2K and NOνA.

  13. Antineutrino Oscillations in the Atmospheric Sector

    SciTech Connect

    Himmel, Alexander I.

    2011-05-01

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

  14. AGM2015: Antineutrino Global Map 2015.

    PubMed

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

    2015-01-01

    Every second greater than 10(25) antineutrinos radiate to space from Earth, shining like a faint antineutrino star. Underground antineutrino detectors have revealed the rapidly decaying fission products inside nuclear reactors, verified the long-lived radioactivity inside our planet, and informed sensitive experiments for probing fundamental physics. Mapping the anisotropic antineutrino flux and energy spectrum advance geoscience by defining the amount and distribution of radioactive power within Earth while critically evaluating competing compositional models of the planet. We present the Antineutrino Global Map 2015 (AGM2015), an experimentally informed model of Earth's surface antineutrino flux over the 0 to 11 MeV energy spectrum, along with an assessment of systematic errors. The open source AGM2015 provides fundamental predictions for experiments, assists in strategic detector placement to determine neutrino mass hierarchy, and aids in identifying undeclared nuclear reactors. We use cosmochemically and seismologically informed models of the radiogenic lithosphere/mantle combined with the estimated antineutrino flux, as measured by KamLAND and Borexino, to determine the Earth's total antineutrino luminosity at . We find a dominant flux of geo-neutrinos, predict sub-equal crust and mantle contributions, with ~1% of the total flux from man-made nuclear reactors. PMID:26323507

  15. AGM2015: Antineutrino Global Map 2015

    NASA Astrophysics Data System (ADS)

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

    2015-09-01

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

  16. AGM2015: Antineutrino Global Map 2015

    PubMed Central

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

    2015-01-01

    Every second greater than 1025 antineutrinos radiate to space from Earth, shining like a faint antineutrino star. Underground antineutrino detectors have revealed the rapidly decaying fission products inside nuclear reactors, verified the long-lived radioactivity inside our planet, and informed sensitive experiments for probing fundamental physics. Mapping the anisotropic antineutrino flux and energy spectrum advance geoscience by defining the amount and distribution of radioactive power within Earth while critically evaluating competing compositional models of the planet. We present the Antineutrino Global Map 2015 (AGM2015), an experimentally informed model of Earth’s surface antineutrino flux over the 0 to 11 MeV energy spectrum, along with an assessment of systematic errors. The open source AGM2015 provides fundamental predictions for experiments, assists in strategic detector placement to determine neutrino mass hierarchy, and aids in identifying undeclared nuclear reactors. We use cosmochemically and seismologically informed models of the radiogenic lithosphere/mantle combined with the estimated antineutrino flux, as measured by KamLAND and Borexino, to determine the Earth’s total antineutrino luminosity at . We find a dominant flux of geo-neutrinos, predict sub-equal crust and mantle contributions, with ~1% of the total flux from man-made nuclear reactors. PMID:26323507

  17. Upper limit on the cross section for elastic neutralino-nucleon scattering in a neutrino experiment at the Baksan Underground Scintillator Telescope

    SciTech Connect

    Suvorova, O. V. Boliev, M. M. Demidov, S. V. Mikheyev, S. P.

    2013-11-15

    The results of a neutrino experiment that involved 24.12 yr of live time of observation of muons from the lower Earth's hemisphere with the aid of the Baksan Underground Scintillator Telescope are presented. In the problem of searches for a signal from the annihilation of dark matter in the Sun, an upper limit on the cross section for the elastic scattering of a weakly interacting massive particle (WIMP) on a nucleon was obtained at a 90% confidence level from an analysis of data accumulated within 21.15 yr of live time of observation. A neutralino in a nonminimal supersymmetric theory was considered for a WIMP. The best limit at the Baksan Underground Scintillator Telescope on the cross section for spin-dependent neutralino interactionwith a proton corresponds to 3 Multiplication-Sign 10{sup -4} pb for the neutralino mass of 210 GeV/c{sup 2}. This limit is three orders of magnitude more stringent than similar limits obtained in experiments that detected directly WIMP scattering on target nuclei.

  18. Towards a Microscopic Understanding of Nucleon Polarizabilities

    NASA Astrophysics Data System (ADS)

    Eichmann, Gernot

    2016-07-01

    We outline a microscopic framework to calculate nucleon Compton scattering from the level of quarks and gluons within the covariant Faddeev approach. We explain the connection with hadronic expansions of the Compton scattering amplitude and discuss the obstacles in maintaining electromagnetic gauge invariance. Finally we give preliminary results for the nucleon polarizabilities.

  19. Toward reactor monitoring with antineutrinos

    SciTech Connect

    Guillon, Benoit; Cormon, S.; Fallot, M.; Giot, L.; Martino, J.; Cribier, M.; Lasserre, T.

    2007-07-01

    The fundamental knowledge on neutrino properties acquired in recent years as well as the great experimental progress made on neutrino detection open nowadays the possibility of applied neutrino physics. Among it, the International Atomic Energy Agency (IAEA) asked to its member states to study the possibility of nuclear reactor monitoring applications, such as the thermal power measurement or the fuel composition bookkeeping. In this context, we report studies aiming at a better determination of the antineutrino energy spectrum emitted by nuclear power plants, necessary for reactor monitoring applications, but also for experiments studying the ground properties of these particles. (authors)

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

    SciTech Connect

    Bhattacharya, Debdatta; /Pittsburgh U.

    2009-03-01

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

  1. How low-energy weak reactions can constrain three-nucleon forces and the neutron-neutron scattering length.

    PubMed

    Gårdestig, A; Phillips, D R

    2006-06-16

    We show that chiral symmetry and gauge invariance enforce relations between the short-distance physics that occurs in a number of electroweak and pionic reactions on light nuclei. Within chiral perturbation theory, this is manifested via the appearance of the same axial isovector two-body contact term in pi(-)d --> nngamma, p-wave pion production in NN collisions, tritium beta decay, pp fusion, nud scattering, and the hep reaction. Using a Gamow-Teller matrix element obtained from calculations of pp fusion as input, we compute the neutron spectrum obtained in pi(-)d --> nngamma. With the short-distance physics in this process controlled from pp --> de(=)nu(e), the theoretical uncertainty in the nn scattering length extracted from pi(-)d --> nngamma is reduced by a factor larger than 3, to approximately < or = 0.05 fm. PMID:16803373

  2. Is Deuterium Nuclear Fusion Catalyzed by Antineutrinos?

    NASA Astrophysics Data System (ADS)

    Shomer, Isaac

    2010-02-01

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

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

    SciTech Connect

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

    2005-09-01

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

  4. Final Report for Monitoring of Reactor Antineutrinos with Compact Germanium Detectors

    SciTech Connect

    Orrell, John L.; Collar, J. I.

    2009-07-01

    This 2008 NCMR project has pursued measurement of the antineutrino-nucleus coherent scattering interaction using a low-energy threshold germanium gamma-ray spectrometer of roughly one-half kilogram total mass. These efforts support development of a compact system for monitoring the antineutrino emission from nuclear reactor cores. Such a monitoring system is relevant to nuclear safeguards and nuclear non-proliferation in general by adding a strong method for assuring quantitative material balance of special nuclear material in the nuclear fuel cycle used in electricity generation.

  5. Reactor monitoring and safeguards using antineutrino detectors

    NASA Astrophysics Data System (ADS)

    Bowden, N. S.

    2008-11-01

    Nuclear reactors have served as the antineutrino source for many fundamental physics experiments. The techniques developed by these experiments make it possible to use these very weakly interacting particles for a practical purpose. The large flux of antineutrinos that leaves a reactor carries information about two quantities of interest for safeguards: the reactor power and fissile inventory. Measurements made with antineutrino detectors could therefore orer an alternative means for verifying the power history and fissile inventory of a reactors, as part of International Atomic Energy Agency (IAEA) and other reactor safeguards regimes. Several erorts to develop this monitoring technique are underway across the globe.

  6. Nucleon Spin And Structure Studies With COMPASS

    SciTech Connect

    Platchkov, Stephane

    2006-07-11

    The COMPASS experiment at CERN investigates nucleon structure and spectroscopy with high-intensity muon and hadron beams. Between 2002 and 2004 COMPASS has mainly concentrated on the spin structure of the nucleon via deep-inelastic scattering of polarized muons on polarized nucleons. First results include measurements of the gluon contribution to the nucleon spin via charm production and high-pt pairs, {lambda} polarization, vector-meson production, Collins and Sivers asymmetries, inclusive and semi-inclusive deep-inelastic scattering asymmetries and a search for pentaquark states. A short overview of these results is presented.

  7. Measurement of the cross section for high-pT hadron production in the scattering of 160-GeV/c muons off nucleons

    NASA Astrophysics Data System (ADS)

    Adolph, C.; Alekseev, M. G.; Alexakhin, V. Yu.; Alexandrov, Yu.; Alexeev, G. D.; Amoroso, A.; Andrieux, V.; Austregesilo, A.; Badełek, B.; Balestra, F.; Barth, J.; Baum, G.; Bedfer, Y.; Berlin, A.; Bernhard, J.; Bertini, R.; Bicker, K.; Bieling, J.; Birsa, R.; Bisplinghoff, J.; Boer, M.; Bordalo, P.; Bradamante, F.; Braun, C.; Bravar, A.; Bressan, A.; Büchele, M.; Burtin, E.; Capozza, L.; Chiosso, M.; Chung, S. U.; Cicuttin, A.; Crespo, M. L.; Dalla Torre, S.; Dasgupta, S. S.; Dasgupta, S.; Denisov, O. Yu.; Donskov, S. V.; Doshita, N.; Duic, V.; Dünnweber, W.; Dziewiecki, M.; Efremov, A.; Elia, C.; Eversheim, P. D.; Eyrich, W.; Faessler, M.; Ferrero, A.; Filin, A.; Finger, M.; Finger, M., Jr.; Fischer, H.; Franco, C.; du Fresne von Hohenesche, N.; Friedrich, J. M.; Frolov, V.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O. P.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gnesi, I.; Gobbo, B.; Goertz, S.; Grabmüller, S.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Guthörl, T.; Haas, F.; von Harrach, D.; Heinsius, F. H.; Herrmann, F.; Heß, C.; Hinterberger, F.; Höppner, Ch.; Horikawa, N.; d'Hose, N.; Huber, S.; Ishimoto, S.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jary, V.; Jasinski, P.; Joosten, R.; Kabuß, E.; Kang, D.; Ketzer, B.; Khaustov, G. V.; Khokhlov, Yu. A.; Kisselev, Yu.; Klein, F.; Klimaszewski, K.; Koivuniemi, J. H.; Kolosov, V. N.; Kondo, K.; Königsmann, K.; Konorov, I.; Konstantinov, V. F.; Kotzinian, A. M.; Kouznetsov, O.; Krämer, M.; Kroumchtein, Z. V.; Kuchinski, N.; Kunne, F.; Kurek, K.; Kurjata, R. P.; Lednev, A. A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Maggiora, A.; Magnon, A.; Makke, N.; Mallot, G. K.; Mann, A.; Marchand, C.; Martin, A.; Marzec, J.; Matsuda, H.; Matsuda, T.; Meshcheryakov, G.; Meyer, W.; Michigami, T.; Mikhailov, Yu. V.; Miyachi, Y.; Morreale, A.; Nagaytsev, A.; Nagel, T.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V. I.; Novakova, C.; Novy, J.; Nowak, W.-D.; Nunes, A. S.; Olshevsky, A. G.; Ostrick, M.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Pesek, M.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V. A.; Pretz, J.; Quaresma, M.; Quintans, C.; Ramos, S.; Reicherz, G.; Rocco, E.; Rodionov, V.; Rondio, E.; Rossiyskaya, N. S.; Ryabchikov, D. I.; Samoylenko, V. D.; Sandacz, A.; Sapozhnikov, M. G.; Sarkar, S.; Savin, I. A.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schlüter, T.; Schmidt, A.; Schmidt, K.; Schmïden, H.; Schmitt, L.; Schönning, K.; Schopferer, S.; Schott, M.; Shevchenko, O. Yu.; Silva, L.; Sinha, L.; Sirtl, S.; Slunecka, M.; Sosio, S.; Sozzi, F.; Srnka, A.; Steiger, L.; Stolarski, M.; Sulc, M.; Sulej, R.; Suzuki, H.; Sznajder, P.; Takekawa, S.; Ter Wolbeek, J.; Tessaro, S.; Tessarotto, F.; Thibaud, F.; Uhl, S.; Uman, I.; Vandenbroucke, M.; Virius, M.; Vondra, J.; Wang, L.; Weisrock, T.; Wilfert, M.; Windmolders, R.; Wiślicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Zhuravlev, N.; Ziembicki, M.

    2013-11-01

    The differential cross section for the production of charged hadrons with high transverse momenta in the scattering of 160GeV/c muons off nucleons at low photon virtualities has been measured at the COMPASS experiment at CERN. The results, which cover transverse momenta from 1.1GeV/c to 3.6GeV/c, are compared to a perturbative quantum chromodynamics (pQCD) calculation, in order to evaluate the applicability of pQCD to this process in the kinematic domain of the experiment. The shape of the calculated differential cross section as a function of transverse momentum is found to be in good agreement with the experimental data, but the absolute scale is underestimated by next-to-leading order pQCD. The inclusion of all-order resummation of large logarithmic threshold corrections reduces the discrepancy from a factor of 3 to 4 to a factor of 2. The dependence of the cross section on the pseudorapidity and on the virtual photon energy fraction is investigated. Finally the dependence on the charge of the hadrons is discussed.

  8. Precompound nucleon angular distributions in the continuum

    SciTech Connect

    Blann, M.; Scobel, W.; Plechaty, E.

    1985-08-01

    Angular distributions for nucleon induced reactions (incident energies 14 to 90 MeV) leading to precompound nucleon emission in the continuum (emitted particle energies 9-70 MeV) are calculated based on nucleon-nucleon scattering kinematics for an incident nucleon on a Fermi gas. Analytic expressions due to Kikuchi and Kawai are used for the single scattering kernel. The geometry dependent hybrid model is used to generate the differential cross sections for first, second, etc. order scattering, these weightings being used to fold the single scattering kernel. Results are found to reproduce all experimental angular distributions quite well at angles in the 20/sup 0/ to 90/sup 0/ range. Ad-hoc modifications to approximate quantal effects and Coulomb deflections are explored, but the results do not seem to offer a consistent means of reproducing back angle yields, and give generally poorer results at very forward angles.

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

    NASA Astrophysics Data System (ADS)

    Berge, P.; Blondel, A.; Böckmann, P.; Burkhardt, H.; Dydak, F.; de Groot, J. G. H.; Grant, A. L.; Hagelberg, R.; Hughes, E. W.; Krasny, M.; Meyer, H. J.; Palazzi, P.; Ranjard, F.; Rothberg, J.; Steinberger, J.; Taureg, H.; Wachsmuth, H.; Wahl, H.; Williams, R. W.; Wotschack, J.; Wysłouch, B.; Blümer, H.; Brummel, H. D.; Buchholz, P.; Duda, J.; Eisele, F.; Kampschulte, B.; Kleinknecht, K.; Knobloch, J.; Müller, E.; Pszola, B.; Renk, B.; Belusević, R.; Falkenburg, B.; Fiedler, M.; Geiges, R.; Geweniger, C.; Hepp, V.; Keilwerth, H.; Kurz, N.; Tittel, K.; Debu, P.; Guyot, C.; Merlo, J. P.; Para, A.; Perez, P.; Perrier, F.; Rander, J.; Schuller, J. P.; Turlay, R.; Vallage, B.; Abramowicz, H.; Królikowski, J.; Lipniacka, A.

    1987-12-01

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

  10. Weak η production off the nucleon

    SciTech Connect

    Alam, M. Rafi; Athar, M. Sajjad; Alvarez-Ruso, L.; Vacas, M. J. Vicente

    2015-05-15

    The weak η-meson production off the nucleon induced by (anti)neutrinos is studied at low and intermediate energies, the range of interest for several ongoing and future neutrino experiments. We consider Born diagrams and the excitation of N{sup *} (1535)S{sub 11} and N{sup *} (1650)S{sub 11} resonances. The vector part of the N-S{sub 11} transition form factors has been obtained from the MAID helicity amplitudes while the poorly known axial part is constrained with the help of the partial conservation of the axial current (PCAC) and assuming the pion-pole dominance of the pseudoscalar form factor.

  11. Nucleon tomography

    NASA Astrophysics Data System (ADS)

    Radici, Marco

    2014-07-01

    Starting from the interpretation of the nucleon electromagnetic form factors in terms of charge/magnetic density, we illustrate the need and the advantages of a multidimensional exploration of the structure of the nucleon, and in general of hadrons. We introduce new tools, like the Generalized Parton Distributions (GPDs) and the Transverse Momentum Distributions (TMDs), which enable us to explore the dynamics of partons beyond the usual collinear approximation adopted in the QCD analysis of hard processes. We emphasize the possibility of using these tools to address the (orbital) angular momentum of partons, and we highlight the latest results on the partonic decomposition of the nucleon spin. We briefly touch on the possible breaking of universality for a specific category of TMDs; as an example, we describe the Sivers effect as a fundamental test of our understanding of the color force in QCD.

  12. A Precise Measurement of Reactor Antineutrino at RENO

    NASA Astrophysics Data System (ADS)

    Jang, J. S.

    2014-06-01

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

  13. Terrestrial and Reactor Antineutrinos in Borexino

    NASA Astrophysics Data System (ADS)

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

    1998-10-01

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

  14. Daya Bay Antineutrino Detector gas system

    NASA Astrophysics Data System (ADS)

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

    2012-11-01

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

  15. A Direction-Sensitive Detector for Electron Antineutrinos

    SciTech Connect

    Brooks, F. D.; Drosg, M.; Smit, F. D.

    2011-12-13

    A modular design is proposed for an electron antineutrino detector based on boron-doped liquid scintillator. Tests have been carried out on small detector systems using neutrons to simulate the antineutrino detection signature. Results from these tests are reported, and the possibility of using a larger system of similar design to detect reactor antineutrinos is discussed.

  16. A Direction-Sensitive Detector for Electron Antineutrinos

    NASA Astrophysics Data System (ADS)

    Brooks, F. D.; Drosg, M.; Smit, F. D.

    2011-12-01

    A modular design is proposed for an electron antineutrino detector based on boron-doped liquid scintillator. Tests have been carried out on small detector systems using neutrons to simulate the antineutrino detection signature. Results from these tests are reported, and the possibility of using a larger system of similar design to detect reactor antineutrinos is discussed.

  17. Nucleon measurements at the precision frontier

    SciTech Connect

    Carlson, Carl E.

    2013-11-07

    We comment on nucleon measurements at the precision frontier. As examples of what can be learned, we concentrate on three topics, which are parity violating scattering experiments, the proton radius puzzle, and the symbiosis between nuclear and atomic physics.

  18. Antineutrino Monitoring for Heavy Water Reactors

    NASA Astrophysics Data System (ADS)

    Christensen, Eric; Huber, Patrick; Jaffke, Patrick; Shea, Thomas E.

    2014-07-01

    In this Letter we discuss the potential application of antineutrino monitoring to the Iranian heavy water reactor at Arak, the IR-40, as a nonproliferation measure. An above ground detector positioned right outside the IR-40 reactor building could meet IAEA verification goals for reactor plutonium inventories. While detectors with the needed spectral sensitivity have been demonstrated below ground, additional research and development is needed to demonstrate an above-ground detector with this same level of sensitivity. In addition to monitoring the reactor during operation, observing antineutrino emissions from long-lived fission products could also allow monitoring the reactor when it is shut down, provided very low detector backgrounds can be achieved. Antineutrino monitoring could also be used to distinguish different levels of fuel enrichment. Most importantly, these capabilities would not require a complete reactor operational history and could provide a means to reestablish continuity of knowledge in safeguards conclusions should this become necessary.

  19. Low-energy pion double charge exchange and nucleon-nucleon correlations in nuclei

    SciTech Connect

    Leitch, M.J.

    1989-01-01

    Recent measurements of pion double-charge exchange (DCX) at energies 20 to 70 MeV are providing a new means for studying nucleon-nucleon correlations in nuclei. At these energies the nucleus is relatively transparent, allowing simpler theoretical models to be used in interpreting the data and leading to a clearer picture. Also the contribution to DCX of sequential charge-exchange scattering through the intermediate analog state is suppressed near 50 MeV and transitions through non-analog intermediate states become very important. Recent theoretical studies by several groups have shown that while transitions through the analog route involve relatively long nucleon-nucleon distances, those through non-analog intermediate states obtain nearly half their strength from nucleon pairs with less than 1 fermi separation. Thus DCX near 50 MeV is an excellent way to study short-range nucleon-nucleon correlations. 31 refs., 29 figs., 4 tabs.

  20. Recent Developments in Neutrino/Antineutrino-Nucleus Interactions

    DOE PAGESBeta

    Morfín, Jorge G.; Nieves, Juan; Sobczyk, Jan T.

    2012-01-01

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

  1. Recent Developments in Neutrino/Antineutrino-Nucleus Interactions

    SciTech Connect

    Morfín, Jorge G.; Nieves, Juan; Sobczyk, Jan T.

    2012-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-02-01

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

  3. Polarized target for nucleon-nucleon experiments at Saturne II

    SciTech Connect

    Ball, J. |; Kasprzyk, T.E.; Khachaturov, B.A.; Lehar, F.; de Lesquen, A.; Sans, J.

    1995-09-01

    Continuous improvements of SATURNE polarized target resulted in a flexible and reliable facility for spin physics. For polarized neutron target, two cartridges loaded with {sup 6}{ital LiD} and {sup 6}{ital LiH} are set in the refrigerator and can be quickly inserted in the beam. The polarized proton target is a 70 cm{sup 3} cartridge loaded with Pentanol-2, a promising material according to the results obtained. Angular distribution as a function of a kinematically conjugate angle and coplanarity in nucleon-nucleon scattering is shown for different targets. {copyright} {ital 1995 American Institute of Physics.}

  4. Dilepton production in nucleon-nucleon collisions revisited

    SciTech Connect

    Shyam, Radhey; Mosel, Ulrich

    2009-01-01

    We present a fully relativistic and gauge invariant framework for calculating the cross sections of dilepton production in nucleon-nucleon ($NN$) collisions which is based on the meson-exchange approximation for the $NN$ scattering amplitudes. Prediction of our model are compared with those of other covariant models that have been used earlier to describe this reaction. Our results are also compared with those of the semiclassical models of this reaction which are employed in the transport model calculations of the dilepton production in nucleus-nucleus collisions. It is found that cross sections obtained within the semiclassical and quantum mechanical models differ noticeably from each other.

  5. Some measurements for determining strangeness matrix elements in the nucleon

    SciTech Connect

    Henley, E.M.; Pollock, S.J.; Ying, S. ); Frederico, T. , Sao Jose dos Campos, SP . Inst. de Estudos Avancados); Krein, . Inst. de Fisica Teorica); Williams, A.G. )

    1991-01-01

    Some experiments to measure strangeness matrix elements of the proton are proposed. Two of these suggestions are described in some detail, namely electro-production of phi mesons and the difference between neutrino and antineutrino scattering for isospin zero targets such as deuterium.

  6. Some measurements for determining strangeness matrix elements in the nucleon

    SciTech Connect

    Henley, E.M.; Pollock, S.J.; Ying, S.; Frederico, T.; Krein,; Williams, A.G.

    1991-12-31

    Some experiments to measure strangeness matrix elements of the proton are proposed. Two of these suggestions are described in some detail, namely electro-production of phi mesons and the difference between neutrino and antineutrino scattering for isospin zero targets such as deuterium.

  7. Weak charged and neutral current induced one pion production off the nucleon

    NASA Astrophysics Data System (ADS)

    Rafi Alam, M.; Sajjad Athar, M.; Chauhan, S.; Singh, S. K.

    2016-02-01

    We present a study of neutrino/antineutrino induced charged current (CC) and neutral current (NC) single pion production (SPP) off the nucleon. For this, we have considered P33(1232) resonance, nonresonant background (NRB) terms, other higher resonances like P11(1440), S11(1535), D13(1520), S11(1650) and P13(1720). For the NRB terms a microscopic approach based on SU(2) nonlinear sigma model has been used. The vector form factors for the resonances are obtained by using the relationship between the electromagnetic resonance form factors and helicity amplitudes provided by MAID. Axial coupling C5A(0) in the case of P33(1232) resonance is obtained by fitting the ANL and BNL ν-deuteron reanalyzed scattering data. The results are presented with and without deuteron effect for the total scattering cross-sections for all possible channels, viz. νl(ν¯l)+N → l-(l+)+N‧+πi and νl(ν¯l)+N → νl(ν¯l)+N‧ + πi, where N,N‧ = p,n, πi = π± or π0 and l = e,μ.

  8. Reactor antineutrino fluxes - Status and challenges

    NASA Astrophysics Data System (ADS)

    Huber, Patrick

    2016-07-01

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

  9. Reference worldwide model for antineutrinos from reactors

    NASA Astrophysics Data System (ADS)

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

    2015-03-01

    Antineutrinos produced at nuclear reactors constitute a severe source of background for the detection of geoneutrinos, which bring to the Earth's surface information about natural radioactivity in the whole planet. In this framework, we provide a reference worldwide model for antineutrinos from reactors, in view of reactors operational records yearly published by the International Atomic Energy Agency. We evaluate the expected signal from commercial reactors for ongoing (KamLAND and Borexino), planned (SNO +), and proposed (Juno, RENO-50, LENA, and Hanohano) experimental sites. Uncertainties related to reactor antineutrino production, propagation, and detection processes are estimated using a Monte Carlo-based approach, which provides an overall site-dependent uncertainty on the signal in the geoneutrino energy window on the order of 3%. We also implement the off-equilibrium correction to the reference reactor spectra associated with the long-lived isotopes, and we estimate a 2.4% increase of the unoscillated event rate in the geoneutrino energy window due to the storage of spent nuclear fuels in the cooling pools. We predict that the research reactors contribute to less than 0.2% to the commercial reactor signal in the investigated 14 sites. We perform a multitemporal analysis of the expected reactor signal over a time lapse of ten years using reactor operational records collected in a comprehensive database published at www.fe.infn.it/antineutrino.

  10. Neutrino-antineutrino annihilation around collapsing star

    NASA Technical Reports Server (NTRS)

    Berezinsky, V. S.; Prilutsky, O. F.

    1985-01-01

    Stellar collapse is accompanied by emission of E sub neutrino approximately 10 MeV neutrinos and antineutrinos with the energy output W sub neutrino approximately 10 to the 53rd power to 10 to the 54th power erg. Annihilation of these particles in the vicinity of collapsar is considered. The physical consequences are discussed.

  11. Determination of antineutrino spectra from nuclear reactors

    SciTech Connect

    Huber, Patrick

    2011-08-15

    In this paper we study the effect of well-known higher-order corrections to the allowed {beta}-decay spectrum on the determination of antineutrino spectra resulting from the decays of fission fragments. In particular, we try to estimate the associated theory errors and find that induced currents like weak magnetism may ultimately limit our ability to improve the current accuracy and under certain circumstance could even greatly increase the theoretical errors. We also perform a critical evaluation of the errors associated with our method to extract the antineutrino spectrum using synthetic {beta} spectra. It turns out that a fit using only virtual {beta} branches with a judicious choice of the effective nuclear charge provides results with a minimal bias. We apply this method to actual data for {sup 235}U, {sup 239}Pu, and {sup 241}Pu and confirm, within errors, recent results, which indicate a net 3% upward shift in energy-averaged antineutrino fluxes. However, we also find significant shape differences which can, in principle, be tested by high-statistics antineutrino data samples.

  12. Nucleon-nucleon theory and phenomenology

    SciTech Connect

    Signell, P.

    1981-03-01

    This project involves five inter-related subprojects: (1) derivation of the intermediate range nucleon-nucleon interaction using a new method that utilizes much shorter and simpler analytic continuation through the unphysical region that lies between the ..pi..N and ..pi pi.. physical regions of the N anti N ..-->.. ..pi pi.. amplitude (with significantly improved accuracy for the nucleon-nucleon interaction); (2) construction of a short range phenomenological potential that, with the theoretical part mentioned above, gives a precise fit to the nucleon-nucleon data and is parameterized for easy use in nucleon calculations; (3) phase shift analyses of the world data below 400 MeV, especially the large amount of very precise data below 20 MeV and the new data near 55 MeV that have never been analyzed properly; (4) the introduction of a K-matrix formulation of the Optimal Polynomial Expansion in order to accelerate convergence of the partial wave series at LAMPF energies; and (5) setting up of a cooperatively evaluated permanent nucleon-nucleon data bank in the 0-1200 MeV range that can be used by all nucleon-nucleon reseachers.

  13. Chiral perturbation theory with nucleons

    SciTech Connect

    Meissner, U.G.

    1991-09-01

    I review the constraints posed on the interactions of pions, nucleons and photons by the spontaneously broken chiral symmetry of QCD. The framework to perform these calculations, chiral perturbation theory, is briefly discussed in the meson sector. The method is a simultaneous expansion of the Greens functions in powers of external moments and quark masses around the massless case, the chiral limit. To perform this expansion, use is made of a phenomenological Lagrangian which encodes the Ward-identities and pertinent symmetries of QCD. The concept of chiral power counting is introduced. The main part of the lectures of consists in describing how to include baryons (nucleons) and how the chiral structure is modified by the fact that the nucleon mass in the chiral limit does not vanish. Particular emphasis is put on working out applications to show the strengths and limitations of the methods. Some processes which are discussed are threshold photopion production, low-energy compton scattering off nucleons, {pi}N scattering and the {sigma}-term. The implications of the broken chiral symmetry on the nuclear forces are briefly described. An alternative approach, in which the baryons are treated as very heavy fields, is touched upon.

  14. Simulated antineutrino signatures of nuclear reactors for nonproliferation applications

    NASA Astrophysics Data System (ADS)

    Misner, Alex C.

    2008-10-01

    Antineutrino detectors could provide a valuable addition to current safeguards regimes. Antineutrinos are an attractive emission to monitor due to their low interaction cross-section that prevents them from being shielded and the dependence of their spectrum on the power level and isotopic content of a reactor core. While there are antineutrino detectors currently deployed at an operational reactor, such observations cannot predict the effect of the diversion of nuclear material on the antineutrino emissions. Utilizing simulation tools, one can predict the antineutrino signatures of such abnormal operations and other reactor types that have not been experimentally measured. This study simulates reactor cores with assembly-level resolution for both baseline and diversion cases in order to predict the properties of a detector for measuring the differences in the antineutrino signatures.

  15. A Precise Measurement of Reactor Antineutrino at RENO

    SciTech Connect

    Jang, J.S.

    2014-06-15

    RENO is the reactor experiment to measure the neutrino mixing angle θ{sub 1}3 by observing the disappearance of the reactor antineutrino. Antineutrinos from six reactors at Yonggwang Nuclear Power Plant in Korea, are detected and compared by two identical detectors located at 294 m and 1383 m, respectively, from the center of the reactor array. The far (near) detector observes 73 (780) electron antineutrino candidate events per day after background subtraction with the precise measurement of reactor antineutrino flux. In this paper, an updated result is presented about the energy spectra of antineutrino signals in RENO detectors. A precise measurement of reactor antineutrino flux is also presented in comparison with expectations.

  16. Parity violation in the nucleon-nucleon interaction

    SciTech Connect

    Haeberli, W.

    1981-01-01

    A short review is presented of experiments designed to detect parity nonconservation (PNC) in the interaction between nucleons. A recent measurement of PNC in proton-proton scattering is described, and some of the methods which were developed to reduce systematic errors to less than or equal to 2 x 10/sup -8/ are discussed. The results of this experiment and of other measurements on PNC are compared to theoretical predictions.

  17. Cooperative Monitoring of Reactors with Antineutrino Detectors

    NASA Astrophysics Data System (ADS)

    Keefer, Greg

    2010-11-01

    The current state-of-the-art in antineutrino detection is such that it is now possible to monitor the operational status, power levels and fissile content of nuclear reactors in real-time at standoff distances of a few tens of meters, well outside of the reactor containment. This has been demonstrated at civilian power reactors in both Russia and the United States. In the last few years, the International Atomic Energy Agency has begun to consider the potential of this technology for its reactor safeguards regime. In this talk, I describe the state of the art for this application, and emphasize the natural overlap with ongoing efforts in fundamental physics to measure the oscillations of antineutrinos using reactor sources.

  18. Flux and spectrum of reactor antineutrinos

    NASA Astrophysics Data System (ADS)

    Kopeikin, V. I.

    2012-02-01

    In order to perform reactor experiments aimed at studying the nature of the neutrino and measurements in the realms of geo- and astrophysical neutrinos and to meet practical requirements in this field, it is highly desirable to obtain deeper insight into the operation of nuclear reactors as a source of antineutrinos. The fluxes and spectra of neutrinos from a reactor in the on and off modes and from a reservoir intended for storing a spent reactor fuel and situated near the reactor being considered are calculated. Features that are peculiar to the flux and spectrum of reactor antineutrinos and which are of importance for implementing and interpreting experiments, but which were disregarded previously, are analyzed here.

  19. Improved predictions of reactor antineutrino spectra

    NASA Astrophysics Data System (ADS)

    Mueller, Th. A.; Lhuillier, D.; Fallot, M.; Letourneau, A.; Cormon, S.; Fechner, M.; Giot, L.; Lasserre, T.; Martino, J.; Mention, G.; Porta, A.; Yermia, F.

    2011-05-01

    Precise predictions of the antineutrino spectra emitted by nuclear reactors is a key ingredient in measurements of reactor neutrino oscillations as well as in recent applications to the surveillance of power plants in the context of nonproliferation of nuclear weapons. We report new calculations including the latest information from nuclear databases and a detailed error budget. The first part of this work is the so-called ab initio approach where the total antineutrino spectrum is built from the sum of all β branches of all fission products predicted by an evolution code. Systematic effects and missing information in nuclear databases lead to final relative uncertainties in the 10-20% range. A prediction of the antineutrino spectrum associated with the fission of U238 is given based on this ab initio method. For the dominant isotopes we developed a more accurate approach combining information from nuclear databases and reference electron spectra associated with the fission of U235, Pu239, and Pu241, measured at Institut Laue-Langevin (ILL) in the 1980s. We show how the anchor point of the measured total β spectra can be used to suppress the uncertainty in nuclear databases while taking advantage of all the information they contain. We provide new reference antineutrino spectra for U235, Pu239, and Pu241 isotopes in the 2-8 MeV range. While the shapes of the spectra and their uncertainties are comparable to those of the previous analysis of the ILL data, the normalization is shifted by about +3% on average. In the perspective of the reanalysis of past experiments and direct use of these results by upcoming oscillation experiments, we discuss the various sources of errors and their correlations as well as the corrections induced by off-equilibrium effects.

  20. Improved predictions of reactor antineutrino spectra

    SciTech Connect

    Mueller, Th. A.; Lhuillier, D.; Letourneau, A.

    2011-05-15

    Precise predictions of the antineutrino spectra emitted by nuclear reactors is a key ingredient in measurements of reactor neutrino oscillations as well as in recent applications to the surveillance of power plants in the context of nonproliferation of nuclear weapons. We report new calculations including the latest information from nuclear databases and a detailed error budget. The first part of this work is the so-called ab initio approach where the total antineutrino spectrum is built from the sum of all {beta} branches of all fission products predicted by an evolution code. Systematic effects and missing information in nuclear databases lead to final relative uncertainties in the 10-20% range. A prediction of the antineutrino spectrum associated with the fission of {sup 238}U is given based on this ab initio method. For the dominant isotopes we developed a more accurate approach combining information from nuclear databases and reference electron spectra associated with the fission of {sup 235}U, {sup 239}Pu, and {sup 241}Pu, measured at Institut Laue-Langevin (ILL) in the 1980s. We show how the anchor point of the measured total {beta} spectra can be used to suppress the uncertainty in nuclear databases while taking advantage of all the information they contain. We provide new reference antineutrino spectra for {sup 235}U, {sup 239}Pu, and {sup 241}Pu isotopes in the 2-8 MeV range. While the shapes of the spectra and their uncertainties are comparable to those of the previous analysis of the ILL data, the normalization is shifted by about +3% on average. In the perspective of the reanalysis of past experiments and direct use of these results by upcoming oscillation experiments, we discuss the various sources of errors and their correlations as well as the corrections induced by off-equilibrium effects.

  1. Cooperative Monitoring of Reactors with Antineutrino Detectors

    NASA Astrophysics Data System (ADS)

    Keefer, Gregory

    2011-04-01

    LLNL and SNL have been exploiting the unique characteristics of reactor antineutrinos for nearly a decade in an effort to develop an independent means of monitoring fissile material diversion for reactor safeguard programs. The current capabilities of antineutrino detectors used in a non-proliferation regime are such that the operational status, power levels and fissile content of the nuclear reactor can be determined in real-time. These experiments were performed at stand-off distances of a few tens of meters. In the last few years, the International Atomic Energy Agency has begun to consider the potential of this technology for its reactor safeguards regime. In this talk, I describe the state of the art for this application, and emphasize the natural overlap with ongoing efforts in fundamental physics to measure the oscillations of antineutrinos using nuclear reactors as sources. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  2. Review of N-N scattering

    SciTech Connect

    Yokosawa, A.

    1980-01-01

    Structures appearing in various experimental data (particularly those with polarized beams) in nucleon-nucleon systems are reviewed. A number of candidates are presented for dibaryon resonances which can couple to nucleon-nucleon systems. The present status of experimental data in the nucleon-nucleon system is discussed. Details of N-N scattering are written elsewhere, and here relatively new aspects are presented.

  3. Three-Nucleon Electroweak Capture Reactions

    SciTech Connect

    L.E. Marcucci; M. Viviani; A. Kievsky; S. Rosati; R. Schiavilla

    2002-10-01

    Recent advances in the study of the p-d radiative and mu-3he weak capture processes are presented and discussed. The three-nucleon bound and scattering states are obtained using the correlated-hyperspherical-harmonics method, with realistic Hamiltonians consisting of the Argonne v14 or Argonne v18 two-nucleon and Tucson-Melbourne or Urbana IX three-nucleon interactions. The electromagnetic and weak transition operators include one- and two-body contributions. The theoretical accuracy achieved in these calculations allows for interesting comparisons with experimental data.

  4. Assembly and Installation of the Daya Bay Antineutrino Detectors

    NASA Astrophysics Data System (ADS)

    Band, H. R.; Brown, R. L.; Carr, R.; Chen, X. C.; Chen, X. H.; Cherwinka, J. J.; Chu, M. C.; Draeger, E.; Dwyer, D. A.; Edwards, W. R.; Gill, R.; Goett, J.; Greenler, L. S.; Gu, W. Q.; He, W. S.; Heeger, K. M.; Heng, Y. K.; Hinrichs, P.; Ho, T. H.; Hoff, M.; Hsiung, Y. B.; Jin, Y.; Kang, L.; Kettell, S. H.; Kramer, M.; Kwan, K. K.; Kwok, M. W.; Lewis, C. A.; Li, G. S.; Li, N.; Li, S. F.; Li, X. N.; Lin, C. J.; Littlejohn, B. R.; Liu, J. L.; Luk, K. B.; Luo, X. L.; Ma, X. Y.; McFarlane, M. C.; McKeown, R. D.; Nakajima, Y.; Ochoa-Ricoux, J. P.; Pagac, A.; Qian, X.; Seilhan, B.; Shih, K.; Steiner, H.; Tang, X.; Themann, H.; Tsang, K. V.; Tsang, R. H. M.; Virostek, S.; Wang, L.; Wang, W.; Wang, Z. M.; Webber, D. M.; Wei, Y. D.; Wen, L. J.; Wenman, D. L.; Wilhelmi, J.; Wingert, M.; Wise, T.; Wong, H. L. H.; Wu, F. F.; Xiao, Q.; Yang, L.; Zhang, Z. J.; Zhong, W. L.; Zhuang, H. L.

    2013-11-01

    The Daya Bay reactor antineutrino experiment is designed to make a precision measurement of the neutrino mixing angle θ13, and recently made the definitive discovery of its non-zero value. It utilizes a set of eight, functionally identical antineutrino detectors to measure the reactor flux and spectrum at baselines of ~ 300-2000 m from the Daya Bay and Ling Ao Nuclear Power Plants. The Daya Bay antineutrino detectors were built in an above-ground facility and deployed side-by-side at three underground experimental sites near and far from the nuclear reactors. This configuration allows the experiment to make a precision measurement of reactor antineutrino disappearance over km-long baselines and reduces relative systematic uncertainties between detectors and nuclear reactors. This paper describes the assembly and installation of the Daya Bay antineutrino detectors.

  5. Uncertainty analysis of fission fraction for reactor antineutrino experiments

    NASA Astrophysics Data System (ADS)

    Ma, X. B.; Lu, F.; Wang, L. Z.; Chen, Y. X.; Zhong, W. L.; An, F. P.

    2016-06-01

    Reactor simulation is an important source of uncertainties for a reactor neutrino experiment. Therefore, how to evaluate the antineutrino flux uncertainty results from reactor simulation is an important question. In this study, a method of the antineutrino flux uncertainty result from reactor simulation was proposed by considering the correlation coefficient. In order to use this method in the Daya Bay antineutrino experiment, the open source code DRAGON was improved and used for obtaining the fission fraction and correlation coefficient. The average fission fraction between DRAGON and SCIENCE code was compared and the difference was less than 5% for all the four isotopes. The uncertainty of fission fraction was evaluated by comparing simulation atomic density of four main isotopes with Takahama-3 experiment measurement. After that, the uncertainty of the antineutrino flux results from reactor simulation was evaluated as 0.6% per core for Daya Bay antineutrino experiment.

  6. Long-Distance Nucleon Structure: Theoretical Overview

    NASA Astrophysics Data System (ADS)

    Donnelly, T. William

    2008-04-01

    The electroweak form factors of the nucleon will be discussed, including the electromagnetic form factors extracted from parity-conserving electron scattering from the proton and from light nuclei, the axial-vector form factor from weak interaction studies and the strangeness form factors which can play a role in parity-violating electron scattering. The focus will be placed on what can be learned about the long-distance structure of the nucleon. Several issues of interpretation will also be discussed: higher-order electroweak contributions, problems of interpretation in coordinate space and uncertainties which arise in the case of the neutron where inevitably nuclear structure problems arise.

  7. Antineutrino spectroscopy with large water Cerenkov detectors.

    PubMed

    Beacom, John F; Vagins, Mark R

    2004-10-22

    We propose modifying large water C erenkov detectors by the addition of 0.2% gadolinium trichloride, which is highly soluble, newly inexpensive, and transparent in solution. Since Gd has an enormous cross section for radiative neutron capture, with summation operatorE(gamma)=8 MeV, this would make neutrons visible for the first time in such detectors, allowing antineutrino tagging by the coincidence detection reaction nu (e)+p-->e(+)+n (similarly for nu (mu)). Taking Super-Kamiokande as a working example, dramatic consequences for reactor neutrino measurements, first observation of the diffuse supernova neutrino background, galactic supernova detection, and other topics are discussed. PMID:15525063

  8. Dilepton production in nucleon-nucleon collisions reexamined

    SciTech Connect

    Shyam, R.; Mosel, U.

    2009-03-15

    We present a fully relativistic and gauge-invariant framework for calculating the cross sections of dilepton production in nucleon-nucleon (NN) collisions that is based on the meson-exchange approximation for the NN-scattering amplitudes. Predictions of our model are compared with those of other covariant models that have been used earlier to describe this reaction. Our results are also compared with those of the semiclassical models that are employed to get the input elementary cross sections in the transport model calculations of the dilepton production in nucleus-nucleus collisions. It is found that cross sections obtained within the semiclassical and quantum mechanical models differ noticeably from each other.

  9. Cottingham formula and nucleon polarisabilities

    NASA Astrophysics Data System (ADS)

    Gasser, J.; Hoferichter, M.; Leutwyler, H.; Rusetsky, A.

    2015-08-01

    The difference between the electromagnetic self-energies of proton and neutron can be calculated with the Cottingham formula, which expresses the self-energies as an integral over the electroproduction cross sections - provided the nucleon matrix elements of the current commutator do not contain a fixed pole. We show that, under the same proviso, the subtraction function occurring in the dispersive representation of the virtual Compton forward scattering amplitude is determined by the cross sections. The representation in particular leads to a parameter-free sum rule for the nucleon polarisabilities. We evaluate the sum rule for the difference between the electric polarisabilities of proton and neutron by means of the available parameterisations of the data and compare the result with experiment.

  10. Reactor Monitoring with Antineutrinos - A Progress Report

    NASA Astrophysics Data System (ADS)

    Bernstein, Adam

    2012-08-01

    The Reactor Safeguards regime is the name given to a set of protocols and technologies used to monitor the consumption and production of fissile materials in nuclear reactors. The Safeguards regime is administered by the International Atomic Energy Agency (IAEA), and is an essential component of the global Treaty on Nuclear Nonproliferation, recently renewed by its 189 remaining signators. (The 190th, North Korea, withdrew from the Treaty in 2003). Beginning in Russia in the 1980s, a number of researchers worldwide have experimentally demonstrated the potential of cubic meter scale antineutrino detectors for non-intrusive real-time monitoring of fissile inventories and power output of reactors. The detectors built so far have operated tens of meters from a reactor core, outside of the containment dome, largely unattended and with remote data acquisition for an entire 1.5 year reactor cycle, and have achieved levels of sensitivity to fissile content of potential interest for the IAEA safeguards regime. In this article, I will describe the unique advantages of antineutrino detectors for cooperative monitoring, consider the prospects and benefits of increasing the range of detectability for small reactors, and provide a partial survey of ongoing global research aimed at improving near-field and far field monitoring and discovery of nuclear reactors.

  11. Long Distance Reactor Antineutrino Flux Monitoring

    NASA Astrophysics Data System (ADS)

    Dazeley, Steven; Bergevin, Marc; Bernstein, Adam

    2015-10-01

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

  12. Measurement of the ratio {σ n}/{σ p} in inelastic muon-nucleon scattering at very low χ and Q2

    NASA Astrophysics Data System (ADS)

    Adams, M. R.; Aïd, S.; Anthony, P. L.; Baker, M. D.; Bartlett, J.; Bhatti, A. A.; Braun, H. M.; Busza, W.; Carroll, T. J.; Conrad, J. M.; Coutrakon, G.; Davisson, R.; Derado, I.; Dhawan, S. K.; Dougherty, W.; Dreyer, T.; Dziunikowska, K.; Eckardt, V.; Ecker, U.; Erdmann, M.; Eskreys, A.; Figiel, J.; Gebauer, H. J.; Geesaman, D. F.; Gilman, R.; Green, M. C.; Haas, J.; Halliwell, C.; Hanlon, J.; Hantke, D.; Hughes, V. W.; Jackson, H. E.; Jaffe, D. E.; Jancso, G.; Jansen, D. M.; Kaufman, S.; Kennedy, R. D.; Kirk, T.; Kobrak, H. G. E.; Krzywdzinski, S.; Kunori, S.; Lord, J. J.; Lubatti, H. J.; McLeod, D.; Magill, S.; Malecki, P.; Manz, A.; Melanson, H.; Michael, D. G.; Mohr, W.; Montgomery, H. E.; Morfin, J. G.; Nickerson, R. B.; O'Day, S.; Olkiewicz, K.; Osborne, L.; Papavassiliou, V.; Pawlik, B.; Pipkin, F. M.; Ramberg, E. J.; Röser, A.; Ryan, J. J.; Salvarani, A.; Schellman, H.; Schmitt, M.; Schmitz, N.; Schüler, K. P.; Seyerlein, H. J.; Skuja, A.; Snow, G. A.; Söldner-Rembold, S.; Steinberg, P. H.; Stier, H. E.; Stopa, P.; Swanson, R. A.; Talaga, R.; Tentindo-Repond, S.; Trost, H.-J.; Venkataramania, H.; Vidal, M.; Wilhelm, M.; Wilkes, J.; Wilson, Richard; Wittek, W.; Wolbers, S. A.; Zhao, T.; Fermilab E665 Collaboration

    1993-07-01

    We present results on the cross-section ratio for inelastic muon scattering on neutrons and protons as a function of Bjorken chi;. The data extend to χ values two orders of magnitude smaller than in previous measurements, down to 2×10 -5, for Q2>0.01 GeV 2. The ratio is consistent with unity throughout this new range.

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

    SciTech Connect

    Anderson, Colin E.

    2011-05-01

    flux-averaged, total cross sections for NC 1π0 production on CH2 to be (4.76 ± 0.05stat ± 0.76sys) x 10-40 cm2/nucleon at ν> = 808 MeV for neutrino induced production and (1.48 ± 0.05stat ± 0.23sys) x 10-40 cm2/nucleon at ν> = 664 MeV for antineutrino induced production.

  14. Mapping High x Structure of the Nucleon: which data is missing?

    SciTech Connect

    Smirnov, G.I.

    2005-02-10

    The analysis of numerous experiments on lepton-nucleon and lepton-nucleus deep inelastic scattering reveals several non-trivial features of the nucleon structure, which are particularly interesting in the range of large Bjorken x (x > 0.8). It is shown that new data form the lightest nuclei can provide decisive information needed for the understanding of the nucleon structure.

  15. Future directions for probing two and three nucleon short-range correlations at high energies

    SciTech Connect

    Frankfurt, Leonid; Sargsian, Misak; Strikman, Mark

    2008-10-13

    We summarize recent progress in the studies of the short-rang correlations (SRC) in nuclei in high energy electron and hadron nucleus scattering and suggest directions for the future high energy studies aimed at establishing detailed structure of two-nucleon SRCs, revealing structure of three nucleon SRC correlations and discovering non-nucleonic degrees of freedom in nuclei.

  16. Evaluation of the Antiproton Flux from the Antineutrino Electron Scattering

    NASA Astrophysics Data System (ADS)

    Alekseev, V. V.; Belotsky, K. M.; Bogomolov, Yu V.; Budaev, R. I.; Dunaeva, O. A.; Kirillov, A. A.; Kuznetsov, A. V.; Laletin, M. N.; Lukyanov, A. D.; Malakhov, V. V.; Mayorov, A. G.; Mayorova, M. A.; Mosichkin, A. F.; Okrugin, A. A.; Rodenko, S. A.; Shitova, A. M.

    2016-02-01

    Recent experiments in high enegry cosmic ray physics, PAMELA and AMS-02, excite a new interest to the mechanisms of generation of galactic antiparticles. In spite of the fact that global picture coincides with the predictions of the standard model, there are some black spots stimulating scientists to involve into research a particularly new physics like dark matter. In the present work, we make an attempt to estimate the impact of standard neutrino processes into the total flux of secondary antiprotons detected by contemporary experiments.

  17. Personal History of Nucleon Polarization Experiments

    DOE R&D Accomplishments Database

    Chamberlain, O.

    1984-09-01

    The history of nucleon scattering experiments is reviewed, starting with the observation of large proton polarizations in scattering from light elements such as carbon, and ending with the acceleration of polarized proton beams in high-energy synchrotrons. Special mention is made about significant contributions made by C.L. Oxley, L. Wolfenstein, R.D. Tripp, T. Ypsilantis, A. Abragam, M. Borghini, T. Niinikoski, Froissart, Stora, A.D. Krisch, and L.G. Ratner.

  18. Geoneutrinos and reactor antineutrinos at SNO+

    NASA Astrophysics Data System (ADS)

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

    2016-05-01

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

  19. First direct observation of muon antineutrino disappearance

    DOE PAGESBeta

    Adamson, P.

    2011-07-05

    This letter reports the first direct observation of muon antineutrino disappearance. The MINOS experiment has taken data with an accelerator beam optimized for ν¯μ production, accumulating an exposure of 1.71 x 1020 protons on target. In the Far Detector, 97 charged current ν¯μ events are observed. The no-oscillation hypothesis predicts 156 events and is excluded at 6.3σ. The best fit to oscillation yields |Δm¯2| = (3.36-0.40 +0.46(stat.) ± 0.06(syst.)) x 10-3 eV2, sin2(2 θ¯) = 0.86-0.12+0.11 (stat.) ± 0.01(syst.). The MINOS νμ and ν¯μ measurements are consistent at the 2.0% confidence level, assuming identical underlying oscillation parameters.

  20. Estimating terrestrial uranium and thorium by antineutrino flux measurements

    PubMed Central

    Dye, Stephen T.; Guillian, Eugene H.

    2008-01-01

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

  1. Observation of reactor electron antineutrinos disappearance in the RENO experiment.

    PubMed

    Ahn, J K; Chebotaryov, S; Choi, J H; Choi, S; Choi, W; Choi, Y; Jang, H I; Jang, J S; Jeon, E J; Jeong, I S; Joo, K K; Kim, B R; Kim, B C; Kim, H S; Kim, J Y; Kim, S B; Kim, S H; Kim, S Y; Kim, W; Kim, Y D; Lee, J; Lee, J K; Lim, I T; Ma, K J; Pac, M Y; Park, I G; Park, J S; Park, K S; Shin, J W; Siyeon, K; Yang, B S; Yeo, I S; Yi, S H; Yu, I

    2012-05-11

    The RENO experiment has observed the disappearance of reactor electron antineutrinos, consistent with neutrino oscillations, with a significance of 4.9 standard deviations. Antineutrinos from six 2.8  GW(th) reactors at the Yonggwang Nuclear Power Plant in Korea, are detected by two identical detectors located at 294 and 1383 m, respectively, from the reactor array center. In the 229 d data-taking period between 11 August 2011 and 26 March 2012, the far (near) detector observed 17102 (154088) electron antineutrino candidate events with a background fraction of 5.5% (2.7%). The ratio of observed to expected numbers of antineutrinos in the far detector is 0.920±0.009(stat)±0.014(syst). From this deficit, we determine sin(2)2θ(13)=0.113±0.013(stat)±0.019(syst) based on a rate-only analysis. PMID:23003027

  2. Uncertainties in the anti-neutrino production at nuclear reactors

    NASA Astrophysics Data System (ADS)

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

    2009-04-01

    Anti-neutrino emission rates from nuclear reactors are determined from thermal power measurements and fission rate calculations. The uncertainties in these quantities for commercial power plants and their impact on the calculated interaction rates in \\bar{\

  3. Remarks on the pion-nucleon σ-term

    NASA Astrophysics Data System (ADS)

    Hoferichter, Martin; Ruiz de Elvira, Jacobo; Kubis, Bastian; Meißner, Ulf-G.

    2016-09-01

    The pion-nucleon σ-term can be stringently constrained by the combination of analyticity, unitarity, and crossing symmetry with phenomenological information on the pion-nucleon scattering lengths. Recently, lattice calculations at the physical point have been reported that find lower values by about 3σ with respect to the phenomenological determination. We point out that a lattice measurement of the pion-nucleon scattering lengths could help resolve the situation by testing the values extracted from spectroscopy measurements in pionic atoms.

  4. Impulsive acceleration and scatter-free transport of about 1 MeV per nucleon ions in (He-3)-rich solar particle events

    NASA Technical Reports Server (NTRS)

    Mason, G. M.; Ng, C. K.; Klecker, B.; Green, G.

    1989-01-01

    Impulsive solar energetic particle (SEP) events are studied to: (1) describe a distinct class of SEP ion events observed in interplanetary space, and (2) test models of focused transport through detailed comparisons of numerical model prediction with the data. An attempt will also be made to describe the transport and scattering properties of the interplanetary medium during the times these events are observed and to derive source injection profiles in these events. ISEE 3 and Helios 1 magnetic field and plasma data are used to locate the approximate coronal connection points of the spacecraft to organize the particle anisotropy data and to constrain some free parameters in the modeling of flare events.

  5. Study of Generalized Parton Distributions and Deeply Virtual Compton Scattering on the nucleon with the CLAS and CLAS12 detectors at the Jefferson Laboratory

    SciTech Connect

    Guegan, Baptiste

    2012-11-01

    The exclusive leptoproduction of a real photon is considered to be the "cleanest" way to access the Generalized Parton Distribution (GPD). This process is called Deeply Virtual Compton Scattering (DVCS) lN {yields} lN{gamma} , and is sensitive to all the four GPDs. Measuring the DVCS cross section is one of the main goals of this thesis. In this thesis, we present the work performed to extract on a wide phase-space the DVCS cross-section from the JLab data at a beam energy of 6 GeV.

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

    SciTech Connect

    Stewart, Christopher; Erickson, Anna

    2015-10-28

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

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

    NASA Astrophysics Data System (ADS)

    Stewart, Christopher; Erickson, Anna

    2015-10-01

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

  8. Antineutrino monitoring of burning mixed oxide plutonium fuels

    NASA Astrophysics Data System (ADS)

    Hayes, A. C.; Trellue, H. R.; Nieto, Michael Martin; Wilson, W. B.

    2012-02-01

    Background: Antineutrino monitoring of reactors is an enhanced nuclear safeguard that is being explored by several international groups. A key question is whether such a scheme could be used to verify the destruction of plutonium loaded in a reactor as mixed oxide (MOX) fuel.Purpose: To explore the effectiveness of antineutrino monitoring for the purposes of nuclear accountability and safeguarding of MOX plutonium, we examine the magnitude and temporal variation in the antineutrino signals expected for different loadings of MOX fuels.Methods: Reactor burn simulations are carried out for four different MOX fuel loadings and the antineutrino signals as a function of fuel burnup are computed and compared.Results: The antineutrino signals from reactor-grade and weapons-grade MOX are shown to be distinct from those from burning low enriched uranium, and this signal difference increases as the MOX plutonium fraction of the reactor core increases.Conclusion: Antineutrino monitoring could be used to verify the destruction of plutonium in reactors, although verifying the grade of the plutonium being burned is found to be more challenging.

  9. Higher-order effects in inclusive electron-nucleus scattering.

    SciTech Connect

    Benhar, O.; Fabrocini, A.; Fantoni, S.; Pandharipande, V. R.; Pieper, S. C.; Sick, I.; Physics; INFIN; Univ. of Pisa; SISSA; Univ. of Illinois; SISSA; Univ. Basel

    1995-10-05

    Higher order corrections in the theory of inclusive scattering of high energy electrons by nuclear matter are studied. They involve at least three nucleons, and are due to: (i) the correlations among the spectator nucleons in matter, and (ii) the Pauli blocking of the scattering of the struck nucleon by a spectator nucleon. Their effect on the cross sections is found to be much smaller than those of the two-nucleon correlation hole and of color transparency.

  10. Virtual Compton Scattering

    SciTech Connect

    Helene Fonvieille

    2003-05-01

    Virtual Compton Scattering off the proton: {gamma}^+p --> {gamma}p is a new field of investigation of nucleon structure. Several dedicated experiments have been performed at low c.m. energy and various momentum transfers, yielding specific information on the proton. This talk reviews the concept of nucleon Generalized Polarizabilities and the present experimental status.

  11. Nucleon-Nucleon Total Cross Section

    NASA Technical Reports Server (NTRS)

    Norbury, John W.

    2008-01-01

    The total proton-proton and neutron-proton cross sections currently used in the transport code HZETRN show significant disagreement with experiment in the GeV and EeV energy ranges. The GeV range is near the region of maximum cosmic ray intensity. It is therefore important to correct these cross sections, so that predictions of space radiation environments will be accurate. Parameterizations of nucleon-nucleon total cross sections are developed which are accurate over the entire energy range of the cosmic ray spectrum.

  12. Parton and valon distributions in the nucleon

    SciTech Connect

    Hwa, R.C.; Sajjad Zahir, M.

    1981-06-01

    Structure functions of the nucleon are analyzed in the valon model in which a nucleon is assumed to be a bound state of three valence quark clusters (valons). At high Q/sup 2/ the structure of the valons is described by leading-order results in the perturbative quantum chromodynamics. From the experimental data on deep-inelastic scattering off protons and neutrons, the flavor-dependent valon distributions in the nucleon are determined. Predictions for the parton distributions are then made for high Q/sup 2/ without guesses concerning the quark and gluon distributions at low Q/sup 2/. The sea-quark and gluon distributions are found to have a sharp peak at very small x. Convenient parametrization is provided which interpolates between different numbers of flavors.

  13. Sea Quark Contribution to the Nucleon Spin

    NASA Astrophysics Data System (ADS)

    Benmokhtar, Fatiha

    2015-10-01

    The widespread belief is that proton and neutron, commonly known as nucleons, are each composed of three elementary particles called quarks. But in the last two decades experiments showed that the mass, momentum, spin and electromagnetic properties of the three quarks do not add up to the known proprieties of the nucleon. Theory predicts that a ``sea'' of virtual pairs of quarks and anti-quarks, along with the strong force carrier particles called gluons, should account for the difference. I will present ongoing work on the preparation of an experiment to isolate the contributions of the sea to the nucleon spin using semi-inclusive deep inelastic scattering technique at the Thomas Jefferson National Accelerator Facility.

  14. First direct observation of muon antineutrino disappearance

    SciTech Connect

    Adamson, P.

    2011-07-05

    This letter reports the first direct observation of muon antineutrino disappearance. The MINOS experiment has taken data with an accelerator beam optimized for ν¯μ production, accumulating an exposure of 1.71 x 1020 protons on target. In the Far Detector, 97 charged current ν¯μ events are observed. The no-oscillation hypothesis predicts 156 events and is excluded at 6.3σ. The best fit to oscillation yields |Δm¯2| = (3.36-0.40 +0.46(stat.) ± 0.06(syst.)) x 10-3 eV2, sin2(2 θ¯) = 0.86-0.12+0.11 (stat.) ± 0.01(syst.). The MINOS νμ and ν¯μ measurements are consistent at the 2.0% confidence level, assuming identical underlying oscillation parameters.

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

    SciTech Connect

    Heeger, Karsten M.

    2014-09-13

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

  16. Progress Towards Deployable Antineutrino Detectors for Reactor Safeguards

    SciTech Connect

    Bowden, N; Bernstein, A; Dazeley, S; Keefer, G; Reyna, D; Cabrera-Palmer, B; Kiff, S

    2010-04-05

    Fission reactors emit large numbers of antineutrinos and this flux may be useful for the measurement of two quantities of interest for reactor safeguards: the reactor's power and plutonium inventory throughout its cycle. The high antineutrino flux and relatively low background rates means that simple cubic meter scale detectors at tens of meters standoff can record hundreds or thousands of antineutrino events per day. Such antineutrino detectors would add online, quasi-real-time bulk material accountancy to the set of reactor monitoring tools available to the IAEA and other safeguards agencies with minimal impact on reactor operations. Between 2003 and 2008, our LLNL/SNL collaboration successfully deployed several prototype safeguards detectors at a commercial reactor in order to test both the method and the practicality of its implementation in the field. Partially on the strength of the results obtained from these deployments, an Experts Meeting was convened by the IAEA Novel Technologies Group in 2008 to assess current antineutrino detection technology and examine how it might be incorporated into the safeguards regime. Here we present a summary of our previous deployments and discuss current work that seeks to provide expanded capabilities suggested by the Experts Panel, in particular aboveground detector operation.

  17. Few-Nucleon Research at TUNL: Probing Two- and Three-Nucleon Interactions with Neutrons

    NASA Astrophysics Data System (ADS)

    Howell, C. R.; Tornow, W.; Witała, H.

    2016-03-01

    The central goal of few-nucleon research at the Triangle Universities Nuclear Laboratory (TUNL) is to perform measurements that contribute to advancing ab-initio calculations of nuclear structure and reactions. The program aims include evaluating theoretical treatments of few-nucleon reaction dynamics through strategically comparing theory predictions to data, determining properties of the neutron-neutron interaction that are not accessible in two-nucleon reactions, and searching for evidence of longrange features of three-nucleon interactions, e.g., spin and isospin dependence. This paper will review studies of three- and four-nucleon systems at TUNL conducted using unpolarized and polarized neutron beams. Measurements of neutron-induced reactions performed by groups at TUNL over the last six years are described in comparison with theory predictions. The results are discussed in the context of the program goals stated above. Measurements of vector analyzing powers for elastic scattering in A=3 and A=4 systems, differential cross sections for neutron-deuteron elastic scattering and neutrondeuteron breakup in several final-state configurations are described. The findings from these studies and plans for the coming three years are presented in the context of worldwide activities in this front, in particular, research presented in this session.

  18. Generalized Polarizabilities and the Chiral Structure of the Nucleon

    SciTech Connect

    Hemmert, T.R.; Knoechlein, G.; Holstein, B.R.; Knoechlein, G.; Scherer, S.

    1997-07-01

    We present results of the first chiral perturbation theory calculation for the generalized polarizabilities of the nucleon and discuss the response functions in virtual Compton scattering to be measured in the scheduled electron scattering experiments. {copyright} {ital 1997} {ital The American Physical Society}

  19. The Angra Project: Monitoring Nuclear Reactors with Antineutrino Detectors

    NASA Astrophysics Data System (ADS)

    Anjos, J. C.; Barbosa, A. F.; Bezerra, T. J. C.; Chimenti, P.; Gonzalez, L. F. G.; Kemp, E.; de Oliveira, M. A. Leigui; Lima, H. P.; Lima, R. M.; Nunokawa, H.

    2010-03-01

    We present the status of the Angra Neutrino project, describing the development of an antineutrino detector aimed at monitoring nuclear reactor activity. The experiment will take place at the Brazilian nuclear power plant located in Angra dos Reis. The Angra II reactor, with 4 GW of thermal power, will be used as a source of antineutrinos. A water Cherenkov detector will be placed above ground in a commercial container outside the reactor containment, about 30 m from the reactor core. With a detector of one ton scale a few thousand antineutrino interactions per day are expected. We intend, in a first step, to use the measured neutrino event rate to monitor the on—off status and the thermal power delivered by the reactor. In addition to the safeguards issues the project will provide an alternative tool to have an independent measurement of the reactor power.

  20. Monitoring nuclear reactors for safeguards purposes using anti-neutrinos

    NASA Astrophysics Data System (ADS)

    Carroll, J.; Coleman, J.; Lockwood, M.; Metelko, C.; Murdoch, M.; Touramanis, C.; Davies, G.; Roberts, A.

    2015-04-01

    Preventing nuclear proliferation is a high priority for the international community. Monitoring of nuclear facilities to detect unauthorised removal of fissile materials from operational cores is central to this. Neutrino detection devices can be used to remotely monitor the core of operating reactors in a safe, reliable manner. Technology developed for the T2K experiment can be adapted to make a small footprint, reliable, anti-neutrino detector. Through, characterisation of the anti-neutrino spectrum there is a possibility to provide core material accountancy. A prototype of such a device has been developed and demonstrated at the University of Liverpool. Based on the design of the T2K Near Detector Calorimeter, the device will detect anti-neutrinos through the distinctive delayed coincidence signal of inverse beta decay interactions. This poster presented data from detector commissioning. The detector is currently deployed at Wylfa power station, UK for field testing.

  1. Hard breakup of two nucleons from the He3 nucleus

    NASA Astrophysics Data System (ADS)

    Sargsian, Misak M.; Granados, Carlos

    2009-07-01

    We investigate a large angle photodisintegration of two nucleons from the He3 nucleus within the framework of the hard rescattering model (HRM). In the HRM a quark of one nucleon knocked out by an incoming photon rescatters with a quark of the other nucleon leading to the production of two nucleons with large relative momentum. Assuming the dominance of the quark-interchange mechanism in a hard nucleon-nucleon scattering, the HRM allows the expression of the amplitude of a two-nucleon breakup reaction through the convolution of photon-quark scattering, NN hard scattering amplitude, and nuclear spectral function, which can be calculated using a nonrelativistic He3 wave function. The photon-quark scattering amplitude can be explicitly calculated in the high energy regime, whereas for NN scattering one uses the fit of the available experimental data. The HRM predicts several specific features for the hard breakup reaction. First, the cross section will approximately scale as s-11. Second, the s11 weighted cross section will have the shape of energy dependence similar to that of s10 weighted NN elastic scattering cross section. Also one predicts an enhancement of the pp breakup relative to the pn breakup cross section as compared to the results from low energy kinematics. Another result is the prediction of different spectator momentum dependencies of pp and pn breakup cross sections. This is due to the fact that the same-helicity pp-component is strongly suppressed in the ground state wave function of He3. Because of this suppression the HRM predicts significantly different asymmetries for the cross section of polarization transfer NN breakup reactions for circularly polarized photons. For the pp breakup this asymmetry is predicted to be zero while for the pn it is close to (2)/(3).

  2. Nucleon Form Factors - A Jefferson Lab Perspective

    SciTech Connect

    John Arrington, Kees de Jager, Charles F. Perdrisat

    2011-06-01

    The charge and magnetization distributions of the proton and neutron are encoded in their elastic electromagnetic form factors, which can be measured in elastic electron--nucleon scattering. By measuring the form factors, we probe the spatial distribution of the proton charge and magnetization, providing the most direct connection to the spatial distribution of quarks inside the proton. For decades, the form factors were probed through measurements of unpolarized elastic electron scattering, but by the 1980s, progress slowed dramatically due to the intrinsic limitations of the unpolarized measurements. Early measurements at several laboratories demonstrated the feasibility and power of measurements using polarization degrees of freedom to probe the spatial structure of the nucleon. A program of polarization measurements at Jefferson Lab led to a renaissance in the field of study, and significant new insight into the structure of matter.

  3. Antineutrinos from nuclear reactors: recent oscillation measurements

    NASA Astrophysics Data System (ADS)

    Dwyer, D. A.

    2015-02-01

    Nuclear reactors are the most intense man-made source of antineutrinos, providing a useful tool for the study of these particles. Oscillation due to the neutrino mixing angle {{θ }13} is revealed by the disappearance of reactor {{\\bar{ν }}e} over ˜km distances. Use of additional identical detectors located near nuclear reactors reduce systematic uncertainties related to reactor {{\\bar{ν }}e} emission and detector efficiency, significantly improving the sensitivity of oscillation measurements. The Double Chooz, RENO, and Daya Bay experiments set out in search of {{θ }13} using these techniques. All three experiments have recently observed reactor {{\\bar{ν }}e} disappearance, and have estimated values for {{θ }13} of 9.3◦ ± 2.1°, 9.2◦ ± 0.9°, and 8.7◦ ± 0.4° respectively. The energy-dependence of {{\\bar{ν }}e} disappearance has also allowed measurement of the effective neutrino mass difference, \\mid Δ mee2\\mid ≈ \\mid Δ m312\\mid . Comparison with \\mid Δ mμ μ 2\\mid ≈ \\mid Δ m322\\mid from accelerator {{ν }μ } measurements supports the three-flavor model of neutrino oscillation. The current generation of reactor {{\\bar{ν }}e} experiments are expected to reach ˜3% precision in both {{θ }13} and \\mid Δ mee2\\mid . Precise knowledge of these parameters aids interpretation of planned {{ν }μ } measurements, and allows future experiments to probe the neutrino mass hierarchy and possible CP-violation in neutrino oscillation. Absolute measurements of the energy spectra of {{\\bar{ν }}e} deviate from existing models of reactor emission, particularly in the range of 5-7 MeV.

  4. Spectral structure of electron antineutrinos from nuclear reactors.

    PubMed

    Dwyer, D A; Langford, T J

    2015-01-01

    Recent measurements of the positron energy spectrum obtained from inverse beta decay interactions of reactor electron antineutrinos show an excess in the 4 to 6 MeV region relative to current predictions. First-principles calculations of fission and beta decay processes within a typical pressurized water reactor core identify prominent fission daughter isotopes as a possible origin for this excess. These calculations also predict percent-level substructures in the antineutrino spectrum due to Coulomb effects in beta decay. Precise measurement of these substructures can elucidate the nuclear processes occurring within reactors. These substructures can be a systematic issue for measurements utilizing the detailed spectral shape. PMID:25615462

  5. Scattering Of Light Nuclei

    SciTech Connect

    Quaglioni, S; Navratil, P; Roth, R

    2009-12-15

    The exact treatment of nuclei starting from the constituent nucleons and the fundamental interactions among them has been a long-standing goal in nuclear physics. Above all nuclear scattering and reactions, which require the solution of the many-body quantum-mechanical problem in the continuum, represent an extraordinary theoretical as well as computational challenge for ab initio approaches.We present a new ab initio many-body approach which derives from the combination of the ab initio no-core shell model with the resonating-group method [4]. By complementing a microscopic cluster technique with the use of realistic interactions, and a microscopic and consistent description of the nucleon clusters, this approach is capable of describing simultaneously both bound and scattering states in light nuclei. We will discuss applications to neutron and proton scattering on sand light p-shell nuclei using realistic nucleon-nucleon potentials, and outline the progress toward the treatment of more complex reactions.

  6. Correlations in the in-medium nucleon-nucleon cross section

    SciTech Connect

    Giansiracusa, G.; Lombardo, U.; Sandulescu, N.

    1996-04-01

    The influence of the ground state correlations on the in-medium nucleon-nucleon cross section is investigated in the framework of an extended Brueckner-Hartree-Fock theory of nuclear matter. The effect of the correlations is to overwhelm the suppression of the in-medium {ital NN} cross section already established in previous approximations. Moreover the resulting cross section exceeds largely, particularly for neutron-proton scattering, the free-space values in the low energy range (up to 200{endash}250 MeV) for nuclear medium densities up to two times the saturation density.

  7. Nucleon-nucleon resonances at intermediate energies using a complex energy formalism

    NASA Astrophysics Data System (ADS)

    Papadimitriou, G.; Vary, J. P.

    2015-06-01

    We apply our method of complex scaling, valid for a general class of potentials, in a search for nucleon-nucleon S-matrix poles up to 2 GeV laboratory kinetic energy. We find that the realistic potentials JISP16, constructed from inverse scattering, and chiral field theory potentials N3LO and N2LOopt support resonances in energy regions well above their fit regions. In some cases these resonances have widths that are small when compared with the real part of the S-matrix pole.

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

    SciTech Connect

    Martemyanov, V.P.; Aleshin, V.I.; Tarasenko, V.G.; Tsinoev, V.G.; Sabelnikov, A.A.; Yukhimchuk, A.A.; Popov, V.V.; Baluev, V.V.; Golubkov, A.N.; Klevtsov, V.G.; Kuryakin, A.V.; Sitdikov, D.T.; Bogdanova, L.N.

    2015-03-15

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

  9. Measuring Antineutrino Oscillations with the MINOS Experiment

    SciTech Connect

    Evans, Justin John

    2008-09-01

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

  10. Neutron Capture and the Antineutrino Yield from Nuclear Reactors.

    PubMed

    Huber, Patrick; Jaffke, Patrick

    2016-03-25

    We identify a new, flux-dependent correction to the antineutrino spectrum as produced in nuclear reactors. The abundance of certain nuclides, whose decay chains produce antineutrinos above the threshold for inverse beta decay, has a nonlinear dependence on the neutron flux, unlike the vast majority of antineutrino producing nuclides, whose decay rate is directly related to the fission rate. We have identified four of these so-called nonlinear nuclides and determined that they result in an antineutrino excess at low energies below 3.2 MeV, dependent on the reactor thermal neutron flux. We develop an analytic model for the size of the correction and compare it to the results of detailed reactor simulations for various real existing reactors, spanning 3 orders of magnitude in neutron flux. In a typical pressurized water reactor the resulting correction can reach ∼0.9% of the low energy flux which is comparable in size to other, known low-energy corrections from spent nuclear fuel and the nonequilibrium correction. For naval reactors the nonlinear correction may reach the 5% level by the end of cycle. PMID:27058075

  11. Neutron Capture and the Antineutrino Yield from Nuclear Reactors

    NASA Astrophysics Data System (ADS)

    Huber, Patrick; Jaffke, Patrick

    2016-03-01

    We identify a new, flux-dependent correction to the antineutrino spectrum as produced in nuclear reactors. The abundance of certain nuclides, whose decay chains produce antineutrinos above the threshold for inverse beta decay, has a nonlinear dependence on the neutron flux, unlike the vast majority of antineutrino producing nuclides, whose decay rate is directly related to the fission rate. We have identified four of these so-called nonlinear nuclides and determined that they result in an antineutrino excess at low energies below 3.2 MeV, dependent on the reactor thermal neutron flux. We develop an analytic model for the size of the correction and compare it to the results of detailed reactor simulations for various real existing reactors, spanning 3 orders of magnitude in neutron flux. In a typical pressurized water reactor the resulting correction can reach ˜0.9 % of the low energy flux which is comparable in size to other, known low-energy corrections from spent nuclear fuel and the nonequilibrium correction. For naval reactors the nonlinear correction may reach the 5% level by the end of cycle.

  12. Electron Neutrino and Antineutrino Appearance in the MINOS Detector

    SciTech Connect

    Schreckenberger, Adam Paul

    2013-04-01

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

  13. Renormalization of the Brazilian chiral nucleon-nucleon potential

    SciTech Connect

    Da Rocha, Carlos A.; Timoteo, Varese S.

    2013-03-25

    In this work we present a renormalization of the Brazilian nucleon-nucleon (NN) potential using a subtractive method. We show that the exchange of correlated two pion is important for isovector channels, mainly in tensor and central potentials.

  14. Electromagnetic nucleon form factors

    SciTech Connect

    Bender, A.; Roberts, C.D.; Frank, M.R.

    1995-08-01

    The Dyson-Schwinger equation framework is employed to obtain expressions for the electromagnetic nucleon form factor. In generalized impulse approximation the form factor depends on the dressed quark propagator, the dressed quark-photon vertex, which is crucial to ensuring current conservation, and the nucleon Faddeev amplitude. The approach manifestly incorporates the large space-like-q{sup 2} renormalization group properties of QCD and allows a realistic extrapolation to small space-like-q{sup 2}. This extrapolation allows one to relate experimental data to the form of the quark-quark interaction at small space-like-q{sup 2}, which is presently unknown. The approach provides a means of unifying, within a single framework, the treatment of the perturbative and nonperturbative regimes of QCD. The wealth of experimental nucleon form factor data, over a large range of q{sup 2}, ensures that this application will provide an excellent environment to test, improve and extend our approach.

  15. Predicting Reactor Antineutrino Emissions Using New Precision Beta Spectroscopy

    SciTech Connect

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

    2013-05-01

    Neutrino experiments at nuclear reactors are currently vital to the study of neutrino oscillations. The observed antineutrino rates at reactors are typically lower than model expectations. This observed deficit is called the “reactor neutrino anomaly”. A new understanding of neutrino physics may be required to explain this deficit, though model estimation uncertainties may also play a role in the apparent discrepancy. PNNL is currently investigating an experimental technique that promises reduced uncertainties for measured data to support these hypotheses and interpret reactor antineutrino measurements. The experimental approach is to 1) direct a proton accelerator beam on a metal target to produce a source of neutrons, 2) use spectral tailoring to modify the neutron spectrum to closely simulate the energy distribution of a power reactor neutron spectrum, 3) irradiate isotopic fission foils (235U, 238U, 239Pu, 241Pu) in this neutron spectrum so that fissions occur at energies representative of a reactor, 4) transport the beta particles released by the fission products in the foils to a beta spectrometer, 5) measure the beta energy spectrum, and 6) invert the measured beta energy spectrum to an antineutrino energy spectrum. A similar technique using a beta spectrometer and isotopic fission foils was pioneered in the 1980’s at the ILL thermal reactor. Those measurements have been the basis for interpreting all subsequent antineutrino measurements at reactors. A basic constraint in efforts to reduce uncertainties in predicting the antineutrino emission from reactor cores is any underlying limitation of the original measurements. This may include beta spectrum energy resolution, the absolute normalization of beta emission to number of fission, statistical counting uncertainties, lack of 238U data, the purely thermal nature of the IIL reactor neutrons used, etc. An accelerator-based neutron source that can be tailored to match various reactor neutron spectra

  16. Two-Nucleon Systems in a Finite Volume

    SciTech Connect

    Briceno, Raul

    2014-11-01

    I present the formalism and methodology for determining the nucleon-nucleon scattering parameters from the finite volume spectra obtained from lattice quantum chromodynamics calculations. Using the recently derived energy quantization conditions and the experimentally determined scattering parameters, the bound state spectra for finite volume systems with overlap with the 3S1-3D3 channel are predicted for a range of volumes. It is shown that the extractions of the infinite-volume deuteron binding energy and the low-energy scattering parameters, including the S-D mixing angle, are possible from Lattice QCD calculations of two-nucleon systems with boosts of |P| <= 2pi sqrt{3}/L in volumes with spatial extents L satisfying fm <~ L <~ 14 fm.

  17. Probing short-range nucleon-nucleon interactions with an electron-ion collider

    NASA Astrophysics Data System (ADS)

    Miller, Gerald A.; Sievert, Matthew D.; Venugopalan, Raju

    2016-04-01

    We derive the cross section for exclusive vector meson production in high-energy deeply inelastic scattering off a deuteron target that disintegrates into a proton and a neutron carrying large relative momentum in the final state. This cross section can be expressed in terms of a novel gluon transition generalized parton distribution (T-GPD); the hard scale in the final state makes the T-GPD sensitive to the short-distance nucleon-nucleon interaction. We perform a toy model computation of this process in a perturbative framework and discuss the time scales that allow the separation of initial- and final-state dynamics in the T-GPD. We outline the more general computation based on the factorization suggested by the toy computation: In particular, we discuss the relative role of "pointlike" and "geometric" Fock configurations that control the parton dynamics of short-range nucleon-nucleon scattering. With the aid of exclusive J /ψ production data at the Hadron-Electron Ring Accelerator at DESY, as well as elastic nucleon-nucleon cross sections, we estimate rates for exclusive deuteron photodisintegration at a future Electron-Ion Collider (EIC). Our results, obtained using conservative estimates of EIC integrated luminosities, suggest that center-of-mass energies sNN˜12 GeV2 of the neutron-proton subsystem can be accessed. We argue that the high energies of the EIC can address outstanding dynamical questions regarding the short-range quark-gluon structure of nuclear forces by providing clean gluon probes of such "knockout" exclusive reactions in light and heavy nuclei.

  18. Gluon polarization in nucleon

    NASA Astrophysics Data System (ADS)

    Shahveh, Abolfazl; Taghavi-Shahri, Fatemeh; Arash, Firooz

    2010-07-01

    In the context of the so-called valon model, we calculate δg/g and show that although it is small and compatible with the measured values, the gluon contribution to the spin of nucleon can be sizable. The smallness of δg/g in the measured kinematical region should not be interpreted as δg being small. In fact, δg itself at small x, and the first moment of the polarized gluon distribution in the nucleon, Δg (Q2), are large.

  19. Nucleon Spin Structure: Longitudinal and Transverse

    SciTech Connect

    Jian-Ping Chen

    2011-02-01

    Inclusive Deep-Inelastic Scattering (DIS) experiments have provided us with the most extensive information on the unpolarized and longitudinal polarized parton (quark and gluon) distributions in the nucleon. It has becoming clear that transverse spin and transverse momentum dependent distributions (TMDs) study are crucial for a more complete understanding of the nucleon structure and the dynamics of the strong interaction. The transverse spin structure and the TMDs are the subject of increasingly intense theoretical and experimental study recently. With a high luminosity electron beam facility, JLab has played a major role in the worldwide effort to study both the longitudinal and transverse spin structure. Highlights of recent results will be presented. With 12-GeV energy upgrade, JLab will provide the most precise measurements in the valence quark region to close a chapter in longitudinal spin study. JLab will also perform a multi-dimensional mapping of the transverse spin structure and TMDs in the valence quark region through Semi-Inclusive DIS (SIDIS) experiments, providing a 3-d partonic picture of the nucleon in momentum space and extracting the u and d quark tensor charges of the nucleon. The precision mapping of TMDs will also allow a detailed study of the quark orbital motion and its dynamics.

  20. New Measurements of High-Momentum Nucleons and Short-Range Structures in Nuclei

    SciTech Connect

    Fomin, N.; Arrington, J.; Asaturyan, R.; Benmokhtar, F.; Boeglin, W.; Bosted, P.; Bruell, A.; Bukhari, M. H. S.; Christy, M. E.; Chudakov, E.; Clasie, B.; Connell, S. H.; Dalton, M. M.; Daniel, A.; Day, D. B.; Dutta, D.; Ent, R.; El Fassi, L.; Fenker, H.; Filippone, B. W.; Garrow, K.; Gaskell, D.; Hill, C.; Holt, R. J.; Horn, T.; Jones, M. K.; Jourdan, J.; Kalantarians, N.; Keppel, C. E.; Kiselev, D.; Kotulla, M.; Lindgren, R.; Lung, A. F.; Malace, S.; Markowitz, P.; McKee, P.; Meekins, D. G.; Mkrtchyan, H.; Navasardyan, T.; Niculescu, G.; Opper, A. K.; Perdrisat, C.; Potterveld, D. H.; Punjabi, V.; Qian, X.; Reimer, P. E.; Roche, J.; Rodriguez, V. M.; Rondon, O.; Schulte, E.; Seely, J.; Segbefia, E.; Slifer, K.; Smith, G. R.; Solvignon, P.; Tadevosyan, V.; Tajima, S.; Tang, L.; Testa, G.; Trojer, R.; Tvaskis, V.; Vulcan, W. F.; Wasko, C.; Wesselmann, F. R.; Wood, S. A.; Wright, J.; Zheng, X.

    2012-02-01

    We present new, high-Q2 measurements of inclusive electron scattering from high-momentum nucleons in nuclei. This yields an improved extraction of the strength of two-nucleon correlations for several nuclei, including light nuclei where clustering effects can, for the first time, be examined. The data extend to the kinematic regime where three-nucleon correlations are expected to dominate and we observe significantly greater strength in this region than previous measurements.

  1. New Measurements of High-Momentum Nucleons and Short-Range Structures in Nuclei

    DOE PAGESBeta

    Fomin, N.; Arrington, J.; Asaturyan, R.; Benmokhtar, F.; Boeglin, W.; Bosted, P.; Bruell, A.; Bukhari, M. H. S.; Christy, M. E.; Chudakov, E.; et al

    2012-02-01

    We present new, high-Q2 measurements of inclusive electron scattering from high-momentum nucleons in nuclei. This yields an improved extraction of the strength of two-nucleon correlations for several nuclei, including light nuclei where clustering effects can, for the first time, be examined. The data extend to the kinematic regime where three-nucleon correlations are expected to dominate and we observe significantly greater strength in this region than previous measurements.

  2. Nucleon spin structure

    NASA Astrophysics Data System (ADS)

    Zhu, Wei; Ruan, Jianhong

    2015-10-01

    This paper contains three parts relating to the nucleon spin structure in a simple picture of the nucleon: (i) The polarized gluon distribution in the proton is dynamically predicted starting from a low scale by using a nonlinear quantum chromodynamics (QCD) evolution equation — the Dokshitzer-Gribov-Lipatov-Altarelli-Paris (DGLAP) equation with the parton recombination corrections, where the nucleon is almost consisted only of valence quarks. We find that the contribution of the gluon polarization to the nucleon spin structure is much larger than the predictions of most other theories. This result suggests that a significant orbital angular momentum of the gluons is required to balance the gluon spin momentum. (ii) The spin structure function g1p of the proton is studied, where the perturbative evolution of parton distributions and nonperturbative vector meson dominance (VMD) model are used. We predict g1p asymptotic behavior at small x from lower Q2 to higher Q2. The results are compatible with the data including the early HERA estimations and COMPASS new results. (iii) The generalized Gerasimov-Drell-Hearn (GDH) sum rule is understood based on the polarized parton distributions of the proton with the higher twist contributions. A simple parameterized formula is proposed to clearly present the contributions of different components in the proton to Γ 1p(Q2). The results suggest a possible extended objects with size 0.2-0.3 fm inside the proton.

  3. Generalized Sum Rules of the Nucleon

    NASA Astrophysics Data System (ADS)

    Gorshteyn, Mikhail; Szczepaniak, Adam

    2008-10-01

    We consider doubly virtual Compton scattering (VVCS) off the nucleon with the photon virtualities q1^2=q2^2=-Q^2 and formulate the low energy theorem (LET) for this process. We show that the LET can only be defined at finite momentum transfer t=-2Q^2 which is at variance with existing studies in the literature. Combining LET with dispersion relations for the forward VVCS amplitude, we obtain the new, correct version of the generalized sum rules of the nucleon that state a correspondence between the low energy constants of VVCS and the moments of the DIS structure functions. We notice that the t-channel unitarity is necessary to translate the forward dispersion relations to the low energy limit. This approach leads to a substantial modification of the generalized GDH sum rule at finite Q^2 that undergoes extensive studies at JLab. For the spin-independent VVCS amplitude, the new sum rule for the generalized magnetic susceptibility β(Q^2) is obtained. Our approach provides a consistent, Lorentz invariant formulation of LET for the most general VVCS process that removes inconsistencies that stain the previous studies of the generalized polarizabilities of virtual Compton scattering and the generalized sum rules of the nucleon.

  4. Evidence for new nucleon resonances from electromagnetic meson production

    SciTech Connect

    Volker Burkert

    2012-12-01

    The study of nucleon resonances in electromagnetic meson production with the CLAS detector is discussed. The electromagnetic interaction is complementary to pion scattering in the exploration of the nucleon excitation spectrum. Higher mass states often decouple from the N{pi} channel and are not seen in {pi} N --> {pi} N. Photoproduction of mesons, such as K {Lambda}, {omega} p and {eta}' p may be more sensitive to many of these states. The CLAS detector, combined with the use of energy-tagged polarized photons and polarized electrons, as well as po- larized targets and the measurement of recoil polarization, are the tools needed for a comprehensive nucleon resonance program. Some of the recently published high statistics data sets had significant impact on further clarifying the nucleon excitation spectrum.

  5. From Extraction of Nucleon Resonances to LQCD

    NASA Astrophysics Data System (ADS)

    Lee, T.-S. H.; Wu, Jia-jun; Kamano, Hiroyuki

    2016-06-01

    The intrinsic difficulties in extracting the hadron resonances from reaction data are illustrated by using several exactly soluble π π scattering models. The finite-volume Hamiltonian method is applied to predict spectra using two meson-exchange Hamiltonians of π N reactions. Within a three-channel model with π N , π {Δ} and σ N channels, we show the advantage of the finite-volume Hamiltonian method over the approach using the Lüscher formula to test Lattice QCD calculations aimed at predicting nucleon resonances. We discuss the necessary steps for using the ANL-Osaka eight-channel Hamiltonian to predict the spectra for testing the LQCD calculations for determining the excited nucleon states up to invariant mass W= 2 GeV.

  6. Spin and angular momentum in the nucleon

    SciTech Connect

    Franz Gross, Gilberto Ramalho, Teresa Pena

    2012-05-01

    Using the covariant spectator theory (CST), we present the results of a valence quark-diquark model calculation of the nucleon structure function f(x) measured in unpolarized deep inelastic scattering (DIS), and the structure functions g1(x) and g2(x) measured in DIS using polarized beams and targets. Parameters of the wave functions are adjusted to fit all the data. The fit fixes both the shape of the wave functions and the relative strength of each component. Two solutions are found that fit f(x) and g1(x), but only one of these gives a good description of g2(x). This fit requires the nucleon CST wave functions contain a large D-wave component (about 35%) and a small P-wave component (about 0.6%). The significance of these results is discussed.

  7. Diffraction on nuclei: Effects of nucleon correlations

    SciTech Connect

    Alvioli, M.; Atti, C. Ciofi degli; Kopeliovich, B. Z.; Potashnikova, I. K.; Schmidt, Ivan

    2010-02-15

    The cross sections for a variety of diffractive processes in proton-nucleus scattering, associated with large gaps in rapidity, are calculated within an improved Glauber-Gribov theory, where the inelastic shadowing corrections are summed to all orders by employing the dipole representation. The effects of nucleon correlations, leading to a modification of the nuclear thickness function, are also taken into account. Numerical calculations are performed for the energies of the Hadron-Electron Ring Accelerator-B experiment, the Relativistic Heavy Ion Collider and Large Hadron Collider, and for several nuclei. It is found that whereas the Gribov corrections generally make nuclear matter more transparent, nucleon correlations act in the opposite direction and have important effects in various diffractive processes.

  8. THE SPIN STRUCTURE OF THE NUCLEON.

    SciTech Connect

    VOGELSANG, W.

    2005-05-23

    For many years now, spin has played a very prominent role in QCD. The field of QCD spin physics has been carried by the hugely successful experimental program of polarized deeply-inelastic lepton-nucleon scattering (DIS), and by a simultaneous tremendous progress in theory. A new milestone has now been reached with the advent of RHIC, the world's first polarized proton-proton collider. RHIC is poised to help answer many of the important question pertaining to the spin structure of the nucleon. Recently, it has also been proposed to study spin phenomena in transversely polarized {bar p}p collisions at the planned GSI-FAIR facility. This talk describes some of the opportunities provided by RHIC and the proposed GSI experiments.

  9. Determination of partial-wave inelasticities for elastic pion-nucleon scattering with the aid of experimental data on π N → ππ N processes in the beam-momentum range 300 < P beam < 500 MeV/ c

    NASA Astrophysics Data System (ADS)

    Kozhevnikov, V. A.; Sherman, S. G.

    2008-11-01

    The partial-wave inelasticity parameters of the amplitude for elastic pion-nucleon scattering are determined with the aid of the phenomenological amplitude for inelastic π N → ππ N processes in the energy range extending to the threshold for the production of two pions. The resulting inelasticity parameters are compared with their counterparts derived from modern partial-wave analyses. The largest inelastic-scattering cross section in the P11 wave is in excellent agreement with the analogous value from the analysis performed at the George Washington University in 2006. For other waves, however, the present results differ in the majority of cases from respective values given by partial-wave analyses (the distinctions are especially large for the isospin-3/2 amplitudes).

  10. A letter of intent for a neutrino scattering experiment on the booster neutrino meanline: FINeSSE

    SciTech Connect

    Fleming, B.T.; Tayloe, R.; /Indiana U. /Yale U.

    2005-03-01

    The experiment described in this Letter of Intent provides a decisive measurement of {Delta}s, the spin of the nucleon carried by strange quarks. This is crucial as, after more than thirty years of study, the spin contribution of strange quarks to the nucleon is still not understood. The interpretation of {Delta}s measurements from inclusive Deep Inelastic Scattering (DIS) experiments using charged leptons suffers from two questionable techniques; an assumption of SU(3)-flavor symmetry, and an extrapolation into unmeasured kinematic regions, both of which provide ample room for uncertain theoretical errors in the results. The results of recent semi-inclusive DIS data from HERMES paint a somewhat different picture of the contribution of strange quarks to the nucleon spin than do the inclusive results, but since HERMES does not make use of either of the above-mentioned techniques, then the results are somewhat incomparable. What is required is a measurement directly probing the spin contribution of the strange quarks in the nucleon. Neutrino experiments provide a theoretically clean and robust method of determining {Delta}s by comparing the neutral current interaction, which is isoscalar plus isovector, to the charged current interaction, which is strictly isovector. A past experiment, E734, performed at Brookhaven National Laboratory, has pioneered this effort. Building on what they have learned, we present an experiment which achieves a measurement to {+-} 0.025 using neutrino scattering, and {+-} 0.04 using anti-neutrino scattering, significantly better than past measurements. The combination of the neutrino and anti-neutrino data, when combined with the results of the parity-violating electron-nucleon scattering data, will produce the most significant result for {Delta}s. This experiment can also measure neutrino cross sections in the energy range required for accelerator-based precision oscillation measurements. Accurate measurements of cross sections have been

  11. Nucleon resonances in exclusive reactions of photo- and electroproduction of mesons

    SciTech Connect

    Skorodumina, Iu. A.; Burkert, V. D.; Golovach, E. N.; Gothe, R. W.; Isupov, E. L.; Ishkhanov, B. S.; Mokeev, V. I.; Fedotov, G. V.

    2015-11-01

    Methods for extracting nucleon resonance parameters from experimental data are reviewed. The formalism for the description of exclusive reactions of meson photo- and electroproduction off nucleons is discussed. Recent experimental data on exclusive meson production in the scattering of electrons and photons off protons are analyzed.

  12. Ground-state properties of closed-shell nucleus {sup 56}Ni with realistic nucleon-nucleon interactions

    SciTech Connect

    Gad, Kh.

    2012-10-15

    We have calculated the ground-state energy of the doubly magic nucleus {sup 56}Ni within the framework of the Green's function using the CD-Bonn and N{sup 3}LO nucleon-nucleon potentials. For the sake of comparison, the same calculations are performed using the Brueckner-Hartree-Fock approximation. Both the continuous and conventional choices of single particle energies are used. Additional binding energy is obtained from the inclusion of the hole-hole scattering term within the framework of the Green function approach. In this study, comparison of the calculated ground-state energies, obtained by using the Brueckner-Hartree-Fock approach using continuous choice and different nucleon-nucleon potentials, with the experimental value is accomplished. The results show good agreement between the calculated values and the experimental one for the {sup 56}Ni nucleus. The sensitivity of our results to the choice of the model space is examined.

  13. Time-correlated coincidences at the sudbury neutrino observatory: An antineutrino search

    NASA Astrophysics Data System (ADS)

    Shokair, Timothy Milad

    This dissertation presents a search for antineutrinos in all three phases of data from the Sudbury Neutrino Observatory. This work presents a new method for detecting time correlated coincidences in water detectors. There are two separate searches: an outside search for the inverse beta decay of antineutrinos on protons and an inside search for the inverse beta decay of antineutrinos on deuterons. The inside search found 3 antineutrino candidates in Phase I with an expected background of 3.83+0.71-0.72 events, 28 antineutrino candidates in Phase II with an expected background of 21.25+3.72-3.75 events, 4 antineutrino candidates in Phase III with an expected background of 6.06 +/- 1.14 events. The outside search found 4 antineutrino candidates in Phase I with an expected background of 1.21+0.14-0.17 events, 8 antineutrino candidates in Phase II with an expected background of 9.77+1.06-1.34 events, 0 antineutrino candidates in Phase III with an expected background of 0.46 +/- 0.29 events. Including the expected contribution of antineutrinos from nuclear reactors after oscillations, a limit on the solar antineutrino flux is computed to be F8Bn¯ ≤ 2.5 x 103 cm-2s -1. Taking the flux limit and the measured 8B solar neutrino flux, a limit on the neutrino to antineutrino conversion probability of P(nu → nu) ≤ 5.0 x 10-4. These limits are the best limits from a water detector.

  14. Measuring of fissile isotope partial antineutrino spectra in direct experiment at nuclear reactor

    SciTech Connect

    Sinev, V. V.

    2009-11-15

    The direct measuring method is considered to get nuclear reactor antineutrino spectrum. We suppose to isolate partial spectra of the fissile isotopes by using the method of antineutrino spectrum extraction from the inverse beta-decay reaction positron spectrum applied at Rovno experiment. This admits to increase the accuracy of partial antineutrino spectra forming the total nuclear reactor spectrum. It is important for the analysis of the reactor core fuel composition and could be applied for non-proliferation purposes.

  15. Development of an advanced antineutrino detector for reactor monitoring

    NASA Astrophysics Data System (ADS)

    Classen, T.; Bernstein, A.; Bowden, N. S.; Cabrera-Palmer, B.; Ho, A.; Jonkmans, G.; Kogler, L.; Reyna, D.; Sur, B.

    2015-01-01

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

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

    SciTech Connect

    Djurcic, Zelimir; Detwiler, Jason A.; Piepke, Andreas; Foster Jr., Vince R.; Miller, Lester; Gratta, Giorgio

    2008-08-06

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

  17. Precision Search for Muon Antineutrino Disappearance Oscillations Using a Dual Baseline Technique

    NASA Astrophysics Data System (ADS)

    Cheng, Gary Chia Li

    A search for short baseline muon antineutrino disappearance with the SciBooNE and MiniBooNE experiments at Fermi National Accelerator Laboratory in Batavia, Illinois is presented. Short baseline muon antineutrino disappearance measurements help constrain sterile neutrino models. The two detectors observe muon antineutrinos from the same beam, therefore the combined analysis of their data sets serves to partially constrain some of the flux and cross section uncertainties. A likelihood ratio method was used to set a 90% confidence level upper limit on muon antineutrino disappearance that dramatically improves upon prior sterile neutrino oscillation limits in the Deltam 2=0.1--100 eV2 region.

  18. The NUCLEON space experiment

    NASA Astrophysics Data System (ADS)

    Atkin, E.; Bulatov, V.; Dorokhov, V.; Gorbunov, N.; Filippov, S.; Grebenyuk, V.; Karmanov, D.; Kovalev, I.; Kudryashov, I.; Merkin, M.; Pakhomov, A.; Podorozhny, D.; Polkov, D.; Porokhovoy, S.; Shumikhin, V.; Sveshnikova, L.; Tkachenko, A.; Tkachev, L.; Torochkov, M.; Turundaevskiy, A.; Vasiliev, O.; Voronin, A.

    2015-12-01

    The NUCLEON satellite experiment is designed to investigate directly, above the atmosphere, the energy spectra of cosmic-ray nuclei and the chemical composition (Z= 1 - 30) at energy range 100 GeV- 1000 TeV. The effective geometric factor is more than 0.2 m2sr for nuclei and 0.06 m2sr for electrons. The planned exposition time is more than 5 years.

  19. Probing the nucleon structure with SIDIS at Jefferson Lab

    SciTech Connect

    Pereira, Sergio Anafalos

    2013-01-01

    In recent years, measurements of azimuthal moments of polarized hadronic cross sections in hard processes have emerged as a powerful tool to probe nucleon structure. Many experiments worldwide are currently trying to pin down various effects related to nucleon structure through Semi-Inclusive Deep-Inelastic Scattering (SIDIS). Azimuthal distributions of final-state particles in semi-inclusive deep inelastic scattering, in particular, are sensitive to the orbital motion of quarks and play an important role in the study of Transverse Momentum Dependent parton distribution functions (TMDs) of quarks in the nucleon. The CLAS spectrometer, installed in Hall-B at Jefferson Lab, has collected semi-inclusive data using the CEBAF 6 GeV polarized electron beam on polarized solid NH{sub 3} and ND{sub 3} targets. An overview of these measurements is presented.

  20. Experimental investigation of geologically produced antineutrinos with KamLAND.

    PubMed

    Araki, T; Enomoto, S; Furuno, K; Gando, Y; Ichimura, K; Ikeda, H; Inoue, K; Kishimoto, Y; Koga, M; Koseki, Y; Maeda, T; Mitsui, T; Motoki, M; Nakajima, K; Ogawa, H; Ogawa, M; Owada, K; Ricol, J-S; Shimizu, I; Shirai, J; Suekane, F; Suzuki, A; Tada, K; Takeuchi, S; Tamae, K; Tsuda, Y; Watanabe, H; Busenitz, J; Classen, T; Djurcic, Z; Keefer, G; Leonard, D; Piepke, A; Yakushev, E; Berger, B E; Chan, Y D; Decowski, M P; Dwyer, D A; Freedman, S J; Fujikawa, B K; Goldman, J; Gray, F; Heeger, K M; Hsu, L; Lesko, K T; Luk, K-B; Murayama, H; O'Donnell, T; Poon, A W P; Steiner, H M; Winslow, L A; Mauger, C; McKeown, R D; Vogel, P; Lane, C E; Miletic, T; Guillian, G; Learned, J G; Maricic, J; Matsuno, S; Pakvasa, S; Horton-Smith, G A; Dazeley, S; Hatakeyama, S; Rojas, A; Svoboda, R; Dieterle, B D; Detwiler, J; Gratta, G; Ishii, K; Tolich, N; Uchida, Y; Batygov, M; Bugg, W; Efremenko, Y; Kamyshkov, Y; Kozlov, A; Nakamura, Y; Karwowski, H J; Markoff, D M; Nakamura, K; Rohm, R M; Tornow, W; Wendell, R; Chen, M-J; Wang, Y-F; Piquemal, F

    2005-07-28

    The detection of electron antineutrinos produced by natural radioactivity in the Earth could yield important geophysical information. The Kamioka liquid scintillator antineutrino detector (KamLAND) has the sensitivity to detect electron antineutrinos produced by the decay of 238U and 232Th within the Earth. Earth composition models suggest that the radiogenic power from these isotope decays is 16 TW, approximately half of the total measured heat dissipation rate from the Earth. Here we present results from a search for geoneutrinos with KamLAND. Assuming a Th/U mass concentration ratio of 3.9, the 90 per cent confidence interval for the total number of geoneutrinos detected is 4.5 to 54.2. This result is consistent with the central value of 19 predicted by geophysical models. Although our present data have limited statistical power, they nevertheless provide by direct means an upper limit (60 TW) for the radiogenic power of U and Th in the Earth, a quantity that is currently poorly constrained. PMID:16049478

  1. Strangeness in the Nucleon

    SciTech Connect

    Dahiya, Harleen; Gupta, Manmohan

    2007-10-03

    There are several different experimental indications, such as the {sigma}{sub {pi}}{sub N} term, strange spin polarization, strangeness contribution to the magnetic moment of the proton, ratio of strange and non strange quark flavor distributions which suggest that the nucleon contains a hidden strangeness component which is contradictory to the naive constituent quark model. Chiral constituent quark model with configuration mixing ({chi}CQM{sub config}) is known to provide a satisfactory explanation of the ''proton spin problem'' and related issues. In the present work, we have extended the model to carry out the calculations for the parameters pertaining to the strange quark content of the nucleon, for example, the strange spin polarization {delta}s, strange components of the weak axial vector form factors {delta}{sigma} and {delta}{sub 8} as well as F and D, strangeness magnetic moment of the proton {mu}{sub p}{sup s}, the strange quark content in the nucleon f{sub s} coming from the {sigma}{sub {pi}}{sub N} term, the ratios between strange and non-strange quarks (2s/u+d) and (2s/u-bar+d), contribution of strangeness to angular momentum sum rule etc. Our result demonstrates the broad consistency with the experimental observations as well as other theoretical considerations.

  2. Invited Parallel Talk: Forward pion-nucleon charge exchange reaction and Regge constraints

    NASA Astrophysics Data System (ADS)

    Huang, Fei; Sibirtsev, A.; Krewald, S.; Hanhart, C.; Haidenbauer, J.; Meißner, U.-G.

    2009-12-01

    We present our recent study of pion-nucleon charge exchange amplitudes above 2 GeV. We analyze the forward pion-nucleon charge exchange reaction data in a Regge model and compare the resulting amplitudes with those from the Karlsruhe-Helsinki and George-Washington-University partial-wave analyses. We explore possible high-energy constraints for theoretical baryon resonance analyses in the energy region above 2 GeV. Our results show that for the pion-nucleon charge exchange reaction, the appropriate energy region for matching meson-nucleon dynamics to diffractive scattering should be around 3 GeV for the helicity flip amplitude.

  3. Calculation of multichannel reactions in the four-nucleon system above breakup threshold.

    PubMed

    Deltuva, A; Fonseca, A C

    2014-09-01

    The exact four-body equations of Alt, Grassberger, and Sandhas are solved for neutron-3He and proton-3H scattering in the energy regime above the four-nucleon breakup threshold. Cross sections and spin observables for elastic, transfer, charge-exchange, and breakup reactions are calculated using realistic nucleon-nucleon interaction models, including the one with effective many-nucleon forces due to explicit Δ-isobar excitation. The experimental data are described reasonably well with only few exceptions such as vector analyzing powers. PMID:25238352

  4. EXPLORING THE POLARIZATION OF GLUONS IN THE NUCLEON.

    SciTech Connect

    STRATMANN,M.; VOGELSANG,W.

    2007-10-22

    We give an overview of the current status of investigations of the polarization of gluons in the nucleon. We describe some of the physics of the spin-dependent gluon parton distribution and its phenomenology in high-energy polarized hadronic scattering. We also review the recent experimental results.

  5. Nucleon-antinucleon annihilation in chiral soliton model

    SciTech Connect

    Musakhanov, M.M. . Inst. for Nuclear Theory Tashkentskij Gosudarstvennyj Univ., Tashkent . Dept. of Theoretical Physics); Musatov, I.V. . Research Inst. of Applied Physics)

    1991-09-07

    We investigate annihilation process of nucleons in the chiral soliton model by the path integral method. A soliton-antisoliton pair is shown to decay into mesons at range of about 1fm, defined by the S{bar S} potential. Contribution of the annihilation channel to the elastic scattering is discussed.

  6. Neutrino interactions with nucleons and nuclei at intermediate energies

    SciTech Connect

    Alvarez-Ruso, L.; Leitner, T.; Mosel, U.

    2006-07-11

    We investigate neutrino-nucleus collisions at intermediate energies incorporating quasielastic scattering and {delta}(1232) excitation as elementary processes, together with Fermi motion, Pauli blocking and mean-field potentials in the nuclear medium. A full coupled-channel treatment of final state interactions is achieved with a semiclassical BUU transport model. Results for inclusive reactions and nucleon knockout are presented.

  7. Study of excited nucleon states at EBAC: status and plans

    SciTech Connect

    Hiroyuki Kamano

    2009-12-01

    We present an overview of a research program for the excited nucleon states in Excited Baryon Analysis Center (EBAC) at Jefferson Lab. Current status of our analysis of the meson production reactions based on the unitary dynamical coupled-channels model is summarized, and the N* pole positions extracted from the constructed scattering amplitudes are presented. Our plans for future developments are also discussed.

  8. Four-nucleon potential due to exchange of pions

    SciTech Connect

    Robilotta, M.R.

    1985-03-01

    A four-body force due to the exchange of pions has been derived by means of It includes effects corresponding to pion-pion scattering, pion production, and pion-nucleon rescattering. The strength parameters of this four-body potential are typically one order of magnitude smaller than those of the two-pion-exchange three-body force.

  9. Electromagnetic studies of nucleon and nuclear structure

    SciTech Connect

    Heisenberg, J.H.; Calarco, J.R.; Hersman, F.W.; Dawson, J.F.

    1993-06-01

    Important objectives of the group are the study of subatomic structure through experimental measurements and the interpretation of the data through modeling. The common theme that unifies the studies of strong interactions and hadronic systems is the effort to determine the electromagnetic response as completely as possible. The general approach is coincidence detection of exclusive final states and determination of the dependence on the spin variables using polarized beams and targets and outgoing nucleon polarimetry. Direct reaction and giant resonance studies of electron quasi-elastic scattering on {sup 12}C and {sup 16}O are reported, as well as work on nuclear structure models and instrumentation development.

  10. Nucleon-Nucleon Potential and Its Non-Locality in Lattice QCD

    NASA Astrophysics Data System (ADS)

    Murano, K.; Ishii, N.; Aoki, S.; Hatsuda, T.

    2011-06-01

    By the quenched lattice QCD simulation for two nucleons with finite scattering energy, validity of the derivative expansion of the general nucleon-nucleon potential U({r},{r}') = V({r}, {nabla}_{{r}}) δ^3({r}-{r}') is studied. The relative kinetic energy between two nucleons is introduced through the anti-periodic boundary condition in the spatial directions. On a hypercubic lattice with the lattice spacing a≃ 0.137 fm and the spatial extent L_{s} ≃ 4.4 fm with the pion mass m_{π}≃ 530 MeV, the local potentials for two different energies (E ≃ 0 MeV and 45 MeV) are compared and found to be identical within statistical errors, which validates the local approximation of U({r},{r}) up to E = 45 MeV for the central and tensor potentials. Central potentials in the spin-singlet channel for different orbital angular momentums (ℓ = 0 and ℓ = 2) at E ≃ 45 MeV are also found to be the same within the errors, which also supports the local approximation.

  11. Nucleon-decay-like signatures of hylogenesis

    NASA Astrophysics Data System (ADS)

    Demidov, S. V.; Gorbunov, D. S.

    2016-02-01

    We consider nucleon-decay-like signatures of hylogenesis, a variant of the antibaryonic dark matter model. For the interaction between visible and dark matter sectors through the neutron portal, we calculate the rates of dark matter scatterings off a neutron which mimic neutron-decay processes n →ν γ and n →ν e+e- with richer kinematics. We obtain bounds on the model parameters from nonobservation of the neutron decays by applying the kinematical cuts adopted in the experimental analyses. The bounds are generally (much) weaker than those coming from the recently performed study of events with a single jet of high transverse momentum and missing energy observed at the LHC. Then we suggest several new nucleon-decay-like processes with two mesons in the final state and estimate (accounting for the LHC constraints) the lower limits on the nucleon lifetime with respect to these channels. The obtained values appear to be promising for probing the antibaryonic dark matter at future underground experiments like HyperK and DUNE.

  12. The two-nucleon system at next-to-next-to-next-to-leading order

    SciTech Connect

    Evgeny Epelbaum; Walter Gloeckle; Ulf-G. Meissner

    2005-01-01

    We consider the two-nucleon system at next-to-next-to-next-to-leading order (N{sup 3}LO) in chiral effective field theory. The two--nucleon potential at N{sup 3}LO consists of one-, two- and three-pion exchanges and a set of contact interactions with zero, two and four derivatives. In addition, one has to take into account various isospin--breaking and relativistic corrections. We employ spectral function regularization for the multi--pion exchanges. Within this framework, it is shown that the three-pion exchange contribution is negligibly small. The low--energy constants (LECs) related to pion-nucleon vertices are taken consistently from studies of pion-nucleon scattering in chiral perturbation theory. The total of 26 four--nucleon LECs has been determined by a combined fit to some np and pp phase shifts from the Nijmegen analysis together with the nn scattering length.

  13. QCD vacuum: nuclear forces, nucleons, pions …

    NASA Astrophysics Data System (ADS)

    Robilotta, M. R.

    2011-08-01

    This contribution contains six sections, namely: 1. from QCD to chiral perturbation theory - QCD is widely accepted as the theory of strong interactions, but direct applications to low-energy hadronic processes are difficult. In this regime, the light quarks u and d prevail, and one can employ a rigorously equivalent effective theory, known a chiral perturbation theory, based on hadronic degrees of freedom. 2. strong vacuum and the pion - Chiral symmetry is not exact in the real world. Nevertheless, the absence of of parity multiplets and the smallness of the pion mass suggest that it is a good approximate symmetry, realized in the Nambu-Goldstone mode. Its ground state, the vacuum, is filled with a condensate, made of quark-antiquark pairs. In sections 1-3, instances are presented of observables strongly influenced by the QCD vacuum. 3. nuclear forces - In the last few years, chiral perturbation theory has produced a very reliable picture of both two- and three-nucleon forces. In particular, the important isospin independent central potential VC+ is well understood and known to be dominated by the scalar form factor of the nucleon, a function that describes the disturbance it produces over the vacuum. 4. nucleon scalar form factor - The spatial integration of the nucleon scalar form factor gives rise to σN, the nucleon σ-term. The value of this quantity can be extracted from experiment and the empirical value accepted presently is 45±8 MeV. A simple model, based on the idea that the pion cloud of the nucleon is constructed at the expenses of the surrounding condensate, produces a σN in the range 43-49 MeV, with no free parameters. 5. scalar radius of the pion - The value of this radius can be extracted from pion-pion scattering data and the most reliable estimate is Sπ = 0.61±0.04 fm2. The extension of the model described in section 4 to the pion gives rise to a picture in which it is embedded into the condensate. As one moves towards its center, the

  14. Intra Nucleon Cascade Program

    Energy Science and Technology Software Center (ESTSC)

    1998-08-18

    The package consists of three programs ISABEL, EVA, and PACE-2. ISABEL and PACE-2 are part of the LAHET code. ISABEL is an intra-nucleon cascade program. The output cascades are used as directly as input files to the two evaporation programs EVA and PACE-2. EVA ignores the effect of the angular momentum of the excited nuclei on the deexcitation and also ignores the possibility of gamma emission as long as particle emission is energetically allowed. PACE-2more » takes full account of angular momentum effects including irast levels and gamma emission at all stages of the evaporation chain.« less

  15. Scattering calculations and confining interactions

    NASA Technical Reports Server (NTRS)

    Buck, Warren W.; Maung, Khin M.

    1993-01-01

    Most of the research work performed under this grant were concerned with strong interaction processes ranging from kaon-nucleon interaction to proton-nucleus scattering calculations. Research performed under this grant can be categorized into three groups: (1) parametrization of fundamental interactions, (2) development of formal theory, and (3) calculations based upon the first two. Parametrizations of certain fundamental interactions, such as kaon-nucleon interaction, for example, were necessary because kaon-nucleon scattering amplitude was needed to perform kaon-nucleus scattering calculations. It was possible to calculate kaon-nucleon amplitudes from the first principle, but it was unnecessary for the purpose of the project. Similar work was also done for example for anti-protons and anti-nuclei. Formal developments to some extent were also pursued so that consistent calculations can be done.

  16. Medium Modified Nucleon-Nucleon Cross Sections in a Nucleus

    NASA Technical Reports Server (NTRS)

    Tripathi, R. K.; Cucinotta, F. A.; Wilson, J. W.

    1999-01-01

    A simple reliable formalism is presented for obtaining nucleon-nucleon cross sections within a nucleus in nuclear collisions for a given projectile and target nucleus combination at a given energy for use in transport, Monte Carlo and other calculations. The method relies on extraction of these values from experiments and has been tested for absorption experiments to give excellent results.

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

    SciTech Connect

    Isvan, Zeynep

    2012-01-01

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

  18. Reactor antineutrino monitoring with a plastic scintillator array as a new safeguards method

    NASA Astrophysics Data System (ADS)

    Oguri, S.; Kuroda, Y.; Kato, Y.; Nakata, R.; Inoue, Y.; Ito, C.; Minowa, M.

    2014-09-01

    We developed a segmented reactor-antineutrino detector made of plastic scintillators for application as a tool in nuclear safeguards inspection and performed mostly unmanned field operations at a commercial power plant reactor. At a position outside the reactor building, we measured the difference in reactor antineutrino flux above the ground when the reactor was active and inactive.

  19. The Detection of Reactor Antineutrinos for Reactor Core Monitoring: an Overview

    SciTech Connect

    Fallot, M.

    2014-06-15

    There have been new developments in the field of applied neutrino physics during the last decade. The International Atomic Energy Agency (IAEA) has expressed interest in the potentialities of antineutrino detection as a new tool for reactor monitoring and has created an ad hoc Working Group in late 2010 to follow the associated research and development. Several research projects are ongoing around the world to build antineutrino detectors dedicated to reactor monitoring, to search for and develop innovative detection techniques, or to simulate and study the characteristics of the antineutrino emission of actual and innovative nuclear reactor designs. We give, in these proceedings, an overview of the relevant properties of antineutrinos, the possibilities of and limitations on their detection, and the status of the development of a variety of compact antineutrino detectors for reactor monitoring.

  20. Single-nucleon experiments

    SciTech Connect

    Deur, Alexandre

    2009-12-01

    We discuss the Jefferson Lab low momentum transfer data on moments of the nucleon spin structure functions $g_1$ and $g_2$ and on single charged pion electroproduction off polarized proton and polarized neutron. A wealth of data is now available, while more is being analyzed or expected to be taken in the upcoming years. Given the low momentum transfer selected by the experiments, these data can be compared to calculations from Chiral Perturbation theory, the effective theory of strong force that should describe it at low momentum transfer. The data on various moments and the respective calculations do not consistently agree. In particular, experimental data for higher moments disagree with the calculations.The absence of contribution from the $\\Delta$ resonance in the various observables was expected to facilitate the calculations and hence make the theory predictions either more robust or valid over a larger $Q^2$ range. Such expectation is verified only for the Bjorken sum, but not for other observables in which the $\\Delta$ is suppressed. Preliminary results on pion electroproduction off polarized nucleons are also presented and compared to phenomenological models for which contributions from different resonances are varied. Chiral Perturbation calculations of these observables, while not yet available, would be valuable and, together with these data, would provide an extensive test of the effective theory.

  1. Hermes results on 3D imaging of the nucleon

    NASA Astrophysics Data System (ADS)

    Pappalardo, Luciano L.

    2016-05-01

    The study of the quantum phase-space distribution of quarks and gluons inside nucleons in terms of TMDs and GPDs has become, in the last decade, a cutting-edge research field in hadron physics. These non-perturbative objects, respectively measurable in semi-inclusive deep-inelastic scattering and exclusive processes, allow to obtain 3-dimensional representations of the nucleon in the momentum and spatial coordinates as well as indirect insights into the still unknown parton orbital angular momentum. The HERMES experiment at HERA has been a precursor in this field. A selection of HERMES results sensitive to both TMDs and GPDs is presented.

  2. Hylogenesis and annihilation of nucleons by dark matter

    SciTech Connect

    Davoudiasl, Hooman

    2014-06-24

    In this talk, we briefly present hylogenesis - a unified scenario for simultaneous generation of asymmetric dark matter (ADM) and visible baryons in the early Universe - and some of its experimental implications. A particularly interesting signature of hylogenesis is induced nucleon decay (IND), that is the possibility of baryon destruction in scattering from ADM. For some motivated range of parameters, IND can result in potentially observable signals in nucleon decay experiments. We also briefly discuss other signals of hylogenesis, including collider physics and astrophysical implications of IND.

  3. News on Compton Scattering γX → γX in Chiral EFT

    NASA Astrophysics Data System (ADS)

    Grießhammer, Harald W.; McGovern, Judith A.; Phillips, Daniel R.

    2016-03-01

    We review theoretical progress and prospects to understand the nucleon's static dipole polarisabilities from Compton scattering on few-nucleon targets, including new values; see Refs. [1-5] for details and a more thorough bibliography.

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

    NASA Astrophysics Data System (ADS)

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

    1985-03-01

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

  5. The Muon System of the Daya Bay Reactor Antineutrino Experiment

    DOE PAGESBeta

    An, F. P.; Hackenburg, R. W.; Brown, R. E.; Chasman, C.; Dale, E.; Diwan, M. V.; Gill, R.; Hans, S.; Isvan, Z.; Jaffe, D. E.; et al

    2014-10-05

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

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

    NASA Astrophysics Data System (ADS)

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

    2015-02-01

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

  7. Strangeness in Nucleon

    SciTech Connect

    Benaoum, Hachemi

    2008-04-01

    Results of the parity violating asymmetry APV for longitudinally polarized 3 GeV electrons from both hydrogen and helium cryogenic targets, at small scatteting angle thetalab~6 ° are presented. The asymmetry for hydrogen is a function of a linear combination of GEs and GMs, the strange quark contributions to the electric and magnetic form factors of the nucleon respectively, and that for 4He is a function solely of GEs. The combination of the two results therefore allows GEs and GMs to be separately determined.

  8. Nucleon Electromagnetic Form Factors

    SciTech Connect

    Marc Vanderhaeghen; Charles Perdrisat; Vina Punjabi

    2007-10-01

    There has been much activity in the measurement of the elastic electromagnetic proton and neutron form factors in the last decade, and the quality of the data has greatly improved by performing double polarization experiments, in comparison with previous unpolarized data. Here we review the experimental data base in view of the new results for the proton, and neutron, obtained at JLab, MAMI, and MIT-Bates. The rapid evolution of phenomenological models triggered by these high-precision experiments will be discussed, including the recent progress in the determination of the valence quark generalized parton distributions of the nucleon, as well as the steady rate of improvements made in the lattice QCD calculations.

  9. Neutron Measurements and the Weak Nucleon-Nucleon Interaction

    PubMed Central

    Snow, W. M.

    2005-01-01

    The weak interaction between nucleons remains one of the most poorly-understood sectors of the Standard Model. A quantitative description of this interaction is needed to understand weak interaction phenomena in atomic, nuclear, and hadronic systems. This paper summarizes briefly what is known about the weak nucleon-nucleon interaction, tries to place this phenomenon in the context of other studies of the weak and strong interactions, and outlines a set of measurements involving low energy neutrons which can lead to significant experimental progress. PMID:27308120

  10. Microscopic optical potentials for He4 scattering

    NASA Astrophysics Data System (ADS)

    Egashira, Kei; Minomo, Kosho; Toyokawa, Masakazu; Matsumoto, Takuma; Yahiro, Masanobu

    2014-06-01

    We present a reliable double-folding (DF) model for He4-nucleus scattering, using the Melbourne g-matrix nucleon-nucleon interaction that explains nucleon-nucleus scattering with no adjustable parameter. In the DF model, only the target density is taken as the local density in the Melbourne g matrix. For He4 elastic scattering from Ni58 and Pb208 targets in a wide range of incident energies from 20 to 200 MeV/nucleon, the DF model with the target-density approximation (TDA) yields much better agreement with the experimental data than the usual DF model with the frozen-density approximation in which the sum of projectile and target densities is taken as the local density. We also discuss the relation between the DF model with the TDA and the conventional folding model in which the nucleon-nucleus potential is folded with the He4 density.

  11. New optimal polynomial theory for NN-scattering

    SciTech Connect

    Rijken, T A; Signell, P

    1980-01-01

    A new optimal polynomial theory for nucleon-nucleon scattering is presented. For the first time in nucleon-nucleon scattering, the derivative amplitudes originally introduced by Fubini, Furlan, and Rosetti are applied. Based on the properties of these amplitudes we introduce K-matrix functions which have suitable analyticity properties as functions of cos theta, where theta is the center of mass scattering angle. The K-matrix functions enable introduction of a new set of functions for which the optimal mapping techniques of Cutkosky, Deo and Ciulli can be applied. Results are shown for proton-proton phase shift analyses at 210 and 330 MeV.

  12. Finite volume effects for nucleon and heavy meson masses

    SciTech Connect

    Colangelo, Gilberto; Fuhrer, Andreas; Lanz, Stefan

    2010-08-01

    We apply the resummed version of the Luescher formula to analyze finite volume corrections to the mass of the nucleon and of heavy mesons. We show that by applying the subthreshold expansion of the scattering amplitudes one can express the finite volume corrections in terms of only a few physical observables and the size of the box. In the case of the nucleon, the available information about the quark mass dependence of these physical quantities is discussed and used to assess the finite volume corrections to the nucleon mass as a function of the quark mass including a detailed analysis of the remaining uncertainties. For heavy mesons, the Luescher formula is derived both fully relativistically and in a nonrelativistic approximation and a first attempt at a numerical analysis is made.

  13. Above-ground Antineutrino Detection for Nuclear Reactor Monitoring

    SciTech Connect

    Sweany, Melinda; Brennan, James S.; Cabrera-Palmer, Belkis; Kiff, Scott D.; Reyna, David; Throckmorton, Daniel J.

    2014-08-01

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

  14. Above-ground Antineutrino Detection for Nuclear Reactor Monitoring

    DOE PAGESBeta

    Sweany, Melinda; Brennan, James S.; Cabrera-Palmer, Belkis; Kiff, Scott D.; Reyna, David; Throckmorton, Daniel J.

    2014-08-01

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

  15. Kaon-nucleus scattering

    NASA Technical Reports Server (NTRS)

    Hong, Byungsik; Maung, Khin Maung; Wilson, John W.; Buck, Warren W.

    1989-01-01

    The derivations of the Lippmann-Schwinger equation and Watson multiple scattering are given. A simple optical potential is found to be the first term of that series. The number density distribution models of the nucleus, harmonic well, and Woods-Saxon are used without t-matrix taken from the scattering experiments. The parameterized two-body inputs, which are kaon-nucleon total cross sections, elastic slope parameters, and the ratio of the real to the imaginary part of the forward elastic scattering amplitude, are presented. The eikonal approximation was chosen as our solution method to estimate the total and absorptive cross sections for the kaon-nucleus scattering.

  16. Deeply virtual Compton scattering

    NASA Astrophysics Data System (ADS)

    Marukyan, Hrachya

    2015-11-01

    This paper reviews the experimental measurements in the field of deeply virtual Compton scattering and related theoretical efforts aimed for the extraction of generalized parton distributions, objects, describing the three-dimensional structure of nucleons and nuclei. The future experiments and theoretical expectations are also considered.

  17. Sensitivity of the Antineutrino Emission from Reactors to the Fuel Content

    SciTech Connect

    Hayes-Sterbenz, Anna C

    2012-06-25

    We investigated the antineutrino signals for several reactor core designs. In all cases we found that the antineutrino signals are distinct. The signals are distinguishable by the combination of their magnitudes and their rate of change with fuel burn-up. If the thermal power of the reactor is known, the overall uncertainty in the antineutrino flux emitted from the reactor is about 5%. The quoted uncertainty in the number of antineutrinos per fission for {sup 235}U, {sup 239}Pu, and {sup 241}Pu is less than 3% and for {sup 238}U is 8%. When folded with the uncertainty in the thermal power measurement and the uncertainty in converting the thermal power to a fission rate, the total antineutrino flux is typically quoted with an accuracy of 3-5%. This overall uncertainty in the antineutrino flux, together with the calculations presented here, suggests that the differences in fuels for the class of reactor designed considered would be detectable using antineutrino monitoring.

  18. Experimental studies of nucleon-nucleon and pion-nucleus interactions at intermediate energies

    SciTech Connect

    Not Available

    1990-10-01

    This report summarizes the work on experimental research in intermediate energy nuclear and particle physics carried out by New Mexico State University in 1988--91. Most of these studies have involved investigations of neutron-proton and pion-nucleus interactions. The neutron-proton research is part of a program of studies of interactions between polarized nucleons that we have been involved with for more than ten years. Its purpose has been to help complete the determination of the full set of ten complex nucleon-nucleon amplitudes at energies up to 800 MeV, as well as to continue investigating the possibility of the existence of dibaryon resonances. The give complex isospin-one amplitudes have been fairly well determined, partly as a result of this work. Our work in this period has involved measurements and analysis of data on elastic scattering and total cross sections for polarized neutrons on polarized protons. The pion-nucleus research continues our studies of this interaction in regions where it has not been well explored. One set of experiments includes studies of pion elastic and double-charge-exchange scattering at energies between 300 and 550 MeV, where our data is unique. Another involves elastic and single-charge-exchange scattering of pions from polarized nuclear targets, a new field of research which will give the first extensive set of information on spin-dependent pion-nucleus amplitudes. Still another involves the first set of detailed studies of the kinematic correlations among particles emitted following pion absorption in nuclei.

  19. Search for Electron Antineutrino Appearance at the DELTAm{sup 2}approx1 eV{sup 2} Scale

    SciTech Connect

    Aguilar-Arevalo, A. A.; Anderson, C. E.; Fleming, B. T.; Linden, S. K.; Spitz, J.; Brice, S. J.; Brown, B. C.; Ford, R.; Garcia, F. G.; Kobilarcik, T.; Marsh, W.; Moore, C. D.; Russell, A. D.; Stefanski, R. J.; Bugel, L.; Djurcic, Z.; Mahn, K. B. M.; Shaevitz, M. H.; Sorel, M.; Conrad, J. M.

    2009-09-11

    The MiniBooNE Collaboration reports initial results from a search for nu{sub m}u->nu{sub e} oscillations. A signal-blind analysis was performed using a data sample corresponding to 3.39x10{sup 20} protons on target. The data are consistent with background prediction across the full range of neutrino energy reconstructed assuming quasielastic scattering, 200antineutrino oscillations suggested by data from the Liquid Scintillator Neutrino Detector at Los Alamos National Laboratory.

  20. Soft two-pion-exchange nucleon-nucleon potentials

    SciTech Connect

    Rijken, Th.A. )

    1991-06-01

    Two-pion-exchange nucleon-nucleon potentials are derived for the pseudo-vector pion-nucleon interaction, assuming strong dynamical pair-suppression. At the pion-nucleon vertices the authors include Gaussian form factors, which are incorporated into the relativistic two-body framework by using a dispersion representation for the one-pion-exchange amplitude. The Fourier transformations are performed using a factorization technique for the energy denominators. This leads to analytic expressions for the TPE-potentials containing at most one-dimensional integrals. The TPE-potentials are calculated up to orders {line integral}{sup 4} and (m/M){line integral}{sup 4}. The terms of order {line integral}{sup 4} come from the adiabatic contributions of the parallel and crossed three-dimensional momentum-space TPE-diagrams, and from the non-adiabatic contributions of the OPE-iteration. The (m/M)-corrections are due to the 1/M-terms in the non-adiabatic expansion of the nucleon energies in the intermediate states, and the 1/M-terms in the pion-nucleon vertices. The latter are typical for the PV-coupling and would be absent for the PS-coupling. The Gaussian form factors lead to soft TPE-potentials. These potentials can readily be exploited in NN-calculations in combination with, e.g., the Nijmegen soft-core OBE-model, and in nuclear (matter) calculations.

  1. Antineutrinos for Reactor Safeguards: Effect of Fuel Loading and Burnup on the Signal

    NASA Astrophysics Data System (ADS)

    Erickson, Anna; Bernstein, Adam; Bowden, Nathaniel

    2014-02-01

    Various types of nuclear reactor related information, including relative power level and fuel evolution parameters, can be inferred remotely using antineutrino detectors. We show that it is possible to verify assembly-level burnup using information derived from an antineutrino detector if the nominal reactor fuel loading is known. Alternatively, if the core power is measured using an independent method, for example, a thermal hydraulic element, and the nominal core behavior is known, the antineutrino detector has a capability to determine previously unknown MOX loading in the core.

  2. Total Absorption Spectroscopy Study of (92)Rb Decay: A Major Contributor to Reactor Antineutrino Spectrum Shape.

    PubMed

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

    2015-09-01

    The antineutrino spectra measured in recent experiments at reactors are inconsistent with calculations based on the conversion of integral beta spectra recorded at the ILL reactor. (92)Rb makes the dominant contribution to the reactor antineutrino spectrum in the 5-8 MeV range but its decay properties are in question. We have studied (92)Rb decay with total absorption spectroscopy. Previously unobserved beta feeding was seen in the 4.5-5.5 region and the GS to GS feeding was found to be 87.5(25)%. The impact on the reactor antineutrino spectra calculated with the summation method is shown and discussed. PMID:26382674

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

    NASA Astrophysics Data System (ADS)

    Rykaczewski, Krzysztof

    2015-10-01

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

  4. Perturbation theory for isotropic velocity-dependent potentials: scattering case

    NASA Astrophysics Data System (ADS)

    Jaghoub, Mahmoud

    2010-02-01

    The time-independent Schr"odinger equation with an isotropic velocity-depen-dent potential is considered. Treating the velocity-dependent interaction as a small perturbation we develop analytical formulae for the changes in the scattering phase shifts and wave functions. It is shown that only the zeroth order solution and the perturbing potential are needed to determine the phase shift and wave function corrections. No prior knowledge of the unperturbed scattering states continuum is required. In order to test the validity of our approach we applied it to an exactly solvable model for nucleon-nucleon scattering. The results of the perturbation formalism compare quite well with the those of the exactly solvable model. The developed formalism can be applied in problems concerning pion-nucleon, nucleon-nucleon and electron-atom scattering. It may also be useful in studying the scattering of electrons in semiconductor heterostructures. )

  5. Systematics of meson-Skyrmion scattering

    SciTech Connect

    Mattis, M.P.

    1986-02-01

    The S-matrix characterizing the scattering of pions from nucleons is calculated in the context of skyrmion models of the nucleon. These are models in which the nucleon is considered a soliton in the field of pions. The spectrum of nucleon and delta resonances in the Skyrme model is calculated and found to be in overall good agreement with Nature. Model-independent sum rules between amplitudes in the same partial wave are derived and examined. An extension of the formalism to the case of three light flavors is presented. 31 refs., 26 figs., 6 tabs.

  6. One-Boson Approach to Dilepton Production in Nucleon-Nucleon Collisions.

    NASA Astrophysics Data System (ADS)

    Haglin, Kevin Lee

    1990-01-01

    We calculate energy dependent nucleon-nucleon total elastic cross sections and invariant mass dependent electron-positron pair production differential cross sections for the processes pp to pp, np to np and pp to ppe ^+e^-, pn to pne^+e ^- at laboratory kinetic energies in the 1-5 GeV range. These calculations will be based on relativistic quantum field theory in the one-boson-exchange (pi,rho,omega,sigma,delta, eta) approximation to the nucleon-nucleon scattering problem. There are several independent Feynman diagrams for each process--twenty-five for the case np to npe^+e^ - and forty-eight for the case pp to ppe^+e^- --which, for evaluation, require taking the trace of as many as ten gamma matrices and evaluating an angular integral of a quotient of polynomial functions of initial and final energies, particle masses, coupling constants and so on. These mathematical operations are carried out with the aid of the following algebraic manipulators: for the trace operations we use REDUCE 3.3 on the VAX at the ACS facility and for testing the angular integration algorithms we use MAPLE on the Cray-2 at the Minnesota Supercomputer Institute. Finally, we use Cray-2 Fortran for the resulting numerical substitutions. Gauge invariance is strictly observed while including strong and electromagnetic form factors. The numerical results for these calculations are compared with existing data from the Particle Data Group Booklet and compared with recently released data from the Dilepton Spectrometer (DLS) at the Bevalac of proton on Beryllium. For the latter comparison, the spectrometer's finite acceptance function is introduced before a rapidity and transverse momentum integration.

  7. Comparative analysis of SN1987A antineutrino fluence

    NASA Astrophysics Data System (ADS)

    Vissani, Francesco

    2015-01-01

    We discuss the electron antineutrino fluence derived from the events detected by Kamiokande-II, IMB and Baksan on 23 February 1987. The data are analysed adopting a new simple and accurate formula for the signal, improving on the previous modeling of the detectors response, considering the possibility of background events. We perform several alternative analyses to quantify the relevance of various descriptions, approximations and biases. In particular, we study the effect of: omitting Baksan data or neglecting the background, using simplified formulae for the signal, modifying the fluence to account for oscillations and pinching, including the measured times and angles of the events, using other descriptions of detector response, etc. We show that most of these effects are small or negligible and argue, by comparing the allowed regions for astrophysical parameters, that the results are stable. We comment on the accordance with theoretical results and on open questions.

  8. Very high energy antineutrinos from photo-disintegration of cosmic ray nuclei

    NASA Astrophysics Data System (ADS)

    Gupta, Nayantara

    2016-02-01

    The photo-disintegration of cosmic ray nuclei by starlight leads to the production of secondary antineutrinos. We have assumed that the flux of the ultrahigh energy cosmic ray nuclei near the Galactic plane region is the same as that observed near the earth and calculated the antineutrino flux produced from their photo-disintegration. The IceCube detector has measured the neutrino/antineutrino flux in the TeV-PeV energy range. Our calculated secondary antineutrino flux in the energy range of 10-100 TeV is found to be much less compared to the flux detected by the IceCube collaboration. The upper limit on the intensity of the radiation field in the extragalactic medium is much lower than that near the Galactic center. If we extend our formalism to the extragalactic medium the contribution from the photo-disintegration of ultrahigh energy cosmic ray heavy nuclei remains insignificant due to their very low flux.

  9. Experimental parameters for a reactor antineutrino experiment at very short baselines

    NASA Astrophysics Data System (ADS)

    Heeger, K. M.; Tobin, M. N.; Littlejohn, B. R.; Mumm, H. P.

    2013-04-01

    Reactor antineutrinos are used to study neutrino oscillation, search for signatures of nonstandard neutrino interactions, and monitor reactor operation for safeguard applications. The flux and energy spectrum of reactor antineutrinos can be predicted from the decays of the nuclear fission products. A comparison of recent reactor calculations with past measurements at baselines of 10-100 m suggests a 7.2% deficit. Precision measurements of reactor antineutrinos at very short baselines O(1-10m) can be used to probe this anomaly and search for possible oscillations into sterile neutrino species. This paper studies the experimental requirements for a new reactor antineutrino measurement at very short baselines and calculates the sensitivity of various scenarios. We conclude that, given proper site optimization, detector design, and background reduction, an experiment at a typical research reactor can provide 5σ discovery potential for the favored oscillation parameter space with 3 years of detector live time.

  10. Realistic models of pion-exchange three-nucleon interactions

    SciTech Connect

    Pieper, Steven C.; Pandharipande, V. R.; Wiringa, R. B.; Carlson, J.

    2001-07-01

    We present realistic models of pion-exchange three-nucleon interactions obtained by fitting the energies of all the 17 bound or narrow states of 3{<=}A{<=}8 nucleons, calculated with less than 2% error using the Green's function Monte Carlo method. The models contain two-pion-exchange terms due to {pi}N scattering in S and P waves, three-pion-exchange terms due to ring diagrams with one {Delta} in the intermediate states, and a phenomenological repulsive term to take into account relativistic effects, the suppression of the two-pion-exchange two-nucleon interaction by the third nucleon, and other effects. The models have five parameters, consisting of the strength of the four interactions and the short-range cutoff. The 17 fitted energies are insufficient to determine all of them uniquely. We consider five models, each having three adjustable parameters and assumed values for the other two. They reproduce the observed energies with an rms error <1% when used together with the Argonne v{sub 18} two-nucleon interaction. In one of the models the {pi}N S-wave scattering interaction is set to zero; in all others it is assumed to have the strength suggested by chiral effective-field theory. One of the models also assumes that the {pi}N P-wave scattering interaction has the strength suggested by effective-field theories, and the cutoff is adjusted to fit the data. In all other models the cutoff is taken to be the same as in the v{sub 18} interaction. The effect of relativistic boost correction to the two-nucleon interaction on the strength of the repulsive three-nucleon interaction is estimated. Many calculated properties of A{<=}8 nuclei, including radii, magnetic dipole, and electric quadrupole moments, isobaric analog energy differences, etc., are tabulated. Results obtained with only Argonne v{sub 8}' and v{sub 18} interactions are also reported. In addition, we present results for seven- and eight-body neutron drops in external potential wells.

  11. Remote safeguards and monitoring of reactors with antineutrinos.

    SciTech Connect

    Reyna, David

    2010-10-01

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

  12. Remote safeguards and monitoring of reactors with antineutrinos.

    SciTech Connect

    Kiff, Scott D.; Dazeley, Steven; Reyna, David; Cabrera-Palmer, Belkis; Bernstein, Adam; Keefer, Greg; Bowden, Nathaniel S.

    2010-09-01

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

  13. Above-ground antineutrino detection for nuclear reactor monitoring

    NASA Astrophysics Data System (ADS)

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

    2015-01-01

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

  14. Hermann Grid's Dark Diagonals Disprove QM's ``Beliefs,'' Reveal Stringy Electron, Nucleons, Stick Figure Constellations

    NASA Astrophysics Data System (ADS)

    McLeod, Roger David; McLeod, David Matthew

    2011-11-01

    Vision detects electric field amplitude information from spatial Fourier transforms, SFTs, of object space. Optics states: at focal, not image, surfaces, for Hermann, and pincushion, grids. Von B'ek'esy's skin pressure experiments prove brain circuitry interprets focal diffraction patterns as inverse SFTs. This knocks out QM beliefs, enhanced by Schr"odinger's electron assertions. Mc Leods' electron string model, based on a neutrino in chiral embrace with a parallel, magnetically repellant, antineutrino, transversely aligned in continuous pairings along each wave-string's closure. This generalized, in Recife, PE, Brazil, to the three-ring, up quark, down quark, up quark, of our Dumbo Proton, underpass-overpass string. Cut by an antineutrino scissor, and merged with our compressed, neutrino-cut electron, a Mickey Neutron with over- or underpass pairs only, emerges, is unstable, and is of 4/3 e string units length. Dumbo Proton is 5/3 e units; this string theory predicts a Trinitarian Electron, with charge -1/3 e, whatever phase, Standing Wave Up, SWU, Traveling Wave, TW, or Standing Wave Down, SWD. It explains solar neutrino flux factor 3 shortfall. Camcorders capture this electron at gigapower n values. Peruvian Nazcans recorded high energy, composite nucleon trajectories for us, as ``applied optical (VISION) physicists.''

  15. The Jefferson Lab Contribution to the QCD Spin Structure of the Nucleon

    SciTech Connect

    Michel Garcon

    2004-10-10

    From inclusive to semi-inclusive and exclusive (polarized) deep inelastic scattering, the quark structure of the nucleon is being studied with increasingly precise experiments at Jefferson Lab. We will review here the ongoing programs to determine polarized parton distributions--helicity and transversity--as well as generalized parton distributions, addressing the question of intrinsic spin and orbital angular momentum of quarks in the nucleon.

  16. Three Dimensional Imaging of the Nucleon — TMD (Theory and Phenomenology)

    NASA Astrophysics Data System (ADS)

    Liang, Zuo-Tang

    2016-02-01

    This is intend to provide an overview of the theory and phenomenology parts of the TMD (Transverse Momentum Dependent parton distribution and fragmentation functions) studies. By comparing with the theoretical framework that we have for the inclusive deep inelastic lepton-nucleon scattering and the one-dimensional imaging of the nucleon, I try to outline what we need to do in order to construct a comprehensive theoretical framework for semi-inclusive reactions and the three dimensional imaging of the nucleon. After that, I try to give an overview of what we have already achieved and make an outlook for the future.

  17. Electroexcitation of nucleon resonances

    SciTech Connect

    Inna Aznauryan, Volker D. Burkert

    2012-01-01

    We review recent progress in the investigation of the electroexcitation of nucleon resonances, both in experiment and in theory. The most accurate results have been obtained for the electroexcitation amplitudes of the four lowest excited states, which have been measured in a range of Q2 up to 8 and 4.5 GeV2 for the Delta(1232)P33, N(1535)S11 and N(1440)P11, N(1520)D13, respectively. These results have been confronted with calculations based on lattice QCD, large-Nc relations, perturbative QCD (pQCD), and QCD-inspired models. The amplitudes for the Delta(1232) indicate large pion-cloud contributions at low Q2 and don't show any sign of approaching the pQCD regime for Q2<7 GeV2. Measured for the first time, the electroexcitation amplitudes of the Roper resonance, N(1440)P11, provide strong evidence for this state as a predominantly radial excitation of a three-quark (3q) ground state, with additional non-3-quark contributions needed to describe the low Q2 behavior of the amplitudes. The longitudinal transition amplitude for the N(1535)S11 was determined and has become a challenge for quark models. Explanations may require large meson-cloud contributions or alternative representations of this state. The N(1520)D13 clearly shows the rapid changeover from helicity-3/2 dominance at the real photon point to helicity-1/2 dominance at Q2 > 0.5 GeV2, confirming a long-standing prediction of the constituent quark model. The interpretation of the moments of resonance transition form factors in terms of transition transverse charge distributions in infinite momentum frame is presented.

  18. Weak Deeply Virtual Compton Scattering

    SciTech Connect

    Ales Psaker; Wolodymyr Melnitchouk; Anatoly Radyushkin

    2007-03-01

    We extend the analysis of the deeply virtual Compton scattering process to the weak interaction sector in the generalized Bjorken limit. The virtual Compton scattering amplitudes for the weak neutral and charged currents are calculated at the leading twist within the framework of the nonlocal light-cone expansion via coordinate space QCD string operators. Using a simple model, we estimate cross sections for neutrino scattering off the nucleon, relevant for future high intensity neutrino beam facilities.

  19. Weak production of strange particles and η mesons off the nucleon

    SciTech Connect

    Alam, M. Rafi; Athar, M. Sajjad; Simo, I. Ruiz; Alvarez-Ruso, L.; Vacas, M. J. Vicente

    2015-10-15

    The strange particle production induced by (anti)neutrino off nucleon has been studied for |ΔS| = 0 and |ΔS| = 1 channels. The reactions those we have considered are for the production of single kaon/antikaon, eta and associated particle production processes. We have developed a microscopical model based on the SU(3) chiral Lagrangian. The basic parameters of the model are f{sub π}, the pion decay constant, Cabibbo angle, the proton and neutron magnetic moments and the axial vector coupling constants for the baryons octet. For antikaon production we have also included Σ*(1385) resonance and for eta production S{sub 11}(1535) and S{sub 11}(1650) resonances are included.

  20. Study of opposite-sign dimuon production in high-energy neutrino-nucleon interactions

    NASA Astrophysics Data System (ADS)

    Strongin, B.; Bofill, J.; Friedman, J. I.; Fuess, S.; Goodman, M. C.; Kendall, H. W.; Kistiakowsky, V.; Lyons, T.; Osborne, L. S.; Pitt, R.; Schneekloth, U.; Taylor, F. E.; Bogert, D.; Koizumi, G.; Stutte, L.; Abolins, M.; Brock, R.; Cobau, W.; Hatcher, R.; Owen, D.; Perkins, G.; Tartaglia, M.; Weerts, H.; Belusevic, R.; Walker, J. K.; White, A.; Womersley, J.

    1991-05-01

    Results are presented of a study of opposite-sign dimuon events observed in a fine-grained neutrino detector exposed to the Fermilab Tevatron wide-band neutrino beam. A total of 300 background-corrected μ+μ- events induced by incident neutrinos and antineutrinos with energies up to 500 GeV were accumulated. The data were analyzed in terms of a model based on charm-quark production followed by semileptonic decay of the charmed meson. The Cabibbo-Kobayashi-Maskawa matrix terms were found to be ||Ucd||2=0.0378+/-0.0127 (stat)+0.0099-0.0082 (syst), and κ||Ucs||2=0.391+/-0.076 (stat)+0.097-0.066 (syst). The ratio of the strange to nonstrange sea in the nucleon, κ=2S/(U¯+D¯), was measured to be 0.407+/-0.075 (stat)+0.103-0.069 (syst).

  1. From Nucleons To Nuclei To Fusion Reactions

    SciTech Connect

    Quaglioni, S; Navratil, P; Roth, R; Horiuchi, W

    2012-02-15

    Nuclei are prototypes of many-body open quantum systems. Complex aggregates of protons and neutrons that interact through forces arising from quantum chromo-dynamics, nuclei exhibit both bound and unbound states, which can be strongly coupled. In this respect, one of the major challenges for computational nuclear physics, is to provide a unified description of structural and reaction properties of nuclei that is based on the fundamental underlying physics: the constituent nucleons and the realistic interactions among them. This requires a combination of innovative theoretical approaches and high-performance computing. In this contribution, we present one of such promising techniques, the ab initio no-core shell model/resonating-group method, and discuss applications to light nuclei scattering and fusion reactions that power stars and Earth-base fusion facilities.

  2. Parity-violating nucleon-nucleon force in the 1/N(c) expansion.

    PubMed

    Phillips, Daniel R; Samart, Daris; Schat, Carlos

    2015-02-13

    Several experimental investigations have observed parity violation (PV) in nuclear systems-a consequence of the weak force between quarks. We apply the 1/N(c) expansion of QCD to the P-violating T-conserving component of the nucleon-nucleon (NN) potential. We show there are two leading-order operators, both of which affect p[over →]p scattering at order N(c). We find an additional four operators at order N(c)(0)sin(2)θ(W) and six at O(1/N(c)). Pion exchange in the PV NN force is suppressed by 1/N(c) and sin(2)θ(W), providing a quantitative explanation for its nonobservation up to this time. The large-N(c) hierarchy of other PV NN force mechanisms is consistent with estimates of the couplings in phenomenological models. The PV observed in p[over →]p scattering data is compatible with natural values for the strong and weak coupling constants: there is no evidence of fine-tuning. PMID:25723213

  3. Photon- and meson-induced reactions on the nucleon

    NASA Astrophysics Data System (ADS)

    Feuster, T.; Mosel, U.

    1999-01-01

    Starting from a unitary effective Lagrangian model for the meson-nucleon scattering developed in T. Feuster and U. Mosel, Phys. Rev. 58, 457 (1998), we come to a unified description of both meson scattering and photon-induced reactions on the nucleon. To this end the photon is added perturbatively, yielding both Compton scattering and meson photoproduction amplitudes. In a simultaneous fit to all available data the parameters of the nucleon resonances are extracted. We find that a global fit to the data of the various channels involving the final states γN, πN, ππN, ηN, and KΛ is possible. Especially in eta photoproduction a readjustment of the masses and widths found in the fits to hadronic reactions alone is necessary to describe the data. Only for the D13(1520) do we find a possible disagreement for the helicity couplings extracted using the combined data set and pion photoproduction multipoles alone. The model dependence introduced by the restoration of gauge invariance is discussed and found to be significant mainly for resonances with small helicity couplings.

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

    SciTech Connect

    Fajt, L.; Mamedov, F.; Přidal, P.; Špavorová, M.; Štekl, I.; Belov, V.; Egorov, V. G.; Fomina, M.; Kuznetsov, A.; Ponomarev, D.; Rozova, I.; Zhitnikov, I.; Burešová, H.

    2015-08-17

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

  5. Present status of sensitive detector of reactor's antineutrinos using scintillating detectors

    NASA Astrophysics Data System (ADS)

    Fajt, L.; Belov, V.; Burešová, H.; Egorov, V. G.; Fomina, M.; Kuznetsov, A.; Mamedov, F.; Ponomarev, D.; Přidal, P.; Rozova, I.; Špavorová, M.; Štekl, I.; Zhitnikov, I.

    2015-08-01

    In 2011, the reanalysis of the reactor antineutrinos spectra led to the formulation of the Reactor Antineutrino Anomaly (RAA) [1], which indicates the discrepancy between measured and expected antineutrino fluxes on short baselines. This discrepancy appears to favor the existence of the fourth "sterile" neutrino with |Δm2|>1 eV2. To confirm or reject this hypothesis a high sensitive antineutrino detector located close to the reactor is required. In addition to that such a detector could be used to online monitor the isotopic composition of the reactor core and to prevent illegal production and removal of239Pu, which is the essential part of nuclear weapons. Detector DANSSino [2] already proved that even a compact antineutrino detector (˜ 1 m3) based on polystyrene is capable of antineutrino detection in the close vicinity of a reactor core (˜ 10 m) with signal to background ratio about one. As a common activity between JINR Dubna and IEAP CTU a new prototype of detector (called S3) has been proposed and is under construction. The construction design, selected results of Monte Carlo simulations and results of benchmark tests are presented.

  6. Nucleon spin structure studies at COMPASS

    SciTech Connect

    Marchand, Claude

    2006-02-11

    One of the main goal of the COMPASS experiment at CERN is the study of the spin structure of the nucleon in DIS, by scattering 160 GeV polarized muon beam on a longitudinally (or transversely) polarized 6LiD target. Besides the scattered muon, the particles produced in the deep inelastic scattering are detected by a two stage magnetic spectrometer equipped with state of the art tracking and particle ID detectors.The emphasis of COMPASS muon program is the direct determination of the gluon polarization {delta}G/G, accessed via asymmetries involving photon-gluon fusion mechanism (PGF). Both open charm production (detecting D0's), as well as production of height pT hadron pairs are used to tag PGF. Preliminary results for {delta}G/G based on the analysis of 2002 and 2003 data are shown. In addition, improved measurement of the deuteron structure function g{sub 1}{sup d} at small x, as well as studies of transverse distribution functions in the deuteron by measuring Collins and Sivers azimuthal asymmetries, are reported.

  7. Compton scattering and generalized polarizabilities

    SciTech Connect

    Scherer, S.

    2005-05-06

    In recent years, real and virtual Compton scattering off the nucleon have attracted considerable interest from both the experimental and theoretical sides. Real Compton scattering gives access to the so-called electromagnetic polarizabilities containing the structure information beyond the global properties of the nucleon such as its charge, mass, and magnetic moment. These polarizabilities have an intuitive interpretation in terms of induced dipole moments and thus characterize the response of the constituents of the nucleon to a soft external stimulus. The virtual Compton scattering reaction e- p {yields} e- p{gamma} allows one to map out the local response to external fields and can be described in terms of generalized electromagnetic polarizabilities. A simple classical interpretation in terms of the induced electric and magnetic polarization densities is proposed. We will discuss experimental results for the polarizabilities of the proton and compare them with theoretical predictions.

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

    SciTech Connect

    Li, Y.F.; Xing, Zhi-zhong E-mail: xingzz@ihep.ac.cn

    2011-08-01

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

  9. Nucleon spin decomposition and orbital angular momentum in the nucleon

    NASA Astrophysics Data System (ADS)

    Wakamatsu, Masashi

    2014-09-01

    To get a complete decomposition of nucleon spin is a fundamentally important homework of QCD. In fact, if our researches end up without accomplishing this task, a tremendous efforts since the 1st discovery of the nucleon spin crisis would end in the air. We now have a general agreement that there are at least two physically inequivalent gauge-invariant decompositions of the nucleon. In these two decompositions, the intrinsic spin parts of quarks and gluons are just common. What discriminate these two decompositions are the orbital angular momentum (OAM) parts. The OAMs of quarks and gluons appearing in the first decomposition are the so-called ``mechanical'' OAMs, while those appearing in the second decomposition are the generalized (gauge-invariant) ``canonical'' ones. By this reason, these decompositions are broadly called the ``mechanical'' and ``canonical'' decompositions of the nucleon spin. Still, there remains several issues, which have not reached a complete consensus among the experts. (See the latest recent). In the present talk, I will mainly concentrate on the practically most important issue, i.e. which decomposition is more favorable from the observational viewpoint. There are two often-claimed advantages of canonical decomposition. First, each piece of this decomposition satisfies the SU(2) commutation relation or angular momentum algebra. Second, the canonical OAM rather than the mechanical OAM is compatible with free partonic picture of constituent orbital motion. In the present talk, I will show that both these claims are not necessarily true, and push forward a viewpoint that the ``mechanical'' decomposition is more physical in that it has more direct connection with observables. I also emphasize that the nucleon spin decomposition accessed by the lattice QCD analyses is the ``mechanical'' decomposition not the ``canonical'' one. The recent lattice QCD studies of the nucleon spin decomposition are also briefly overviewed.

  10. Parameterizations of Pion Energy Spectrum in Nucleon-Nucleon Collisions

    NASA Technical Reports Server (NTRS)

    Cucinotta, Franics A.; Wilson, John W.; Norbury, John W.

    1998-01-01

    The effects of pion (PI) production are expected to play an important role in radiation exposures in the upper atmosphere or on the Martian surface. Nuclear databases for describing pion production are developed for radiation transport codes to support these studies. We analyze the secondary energy spectrum of pions produced in nucleon-nucleon (NN) collisions in the relativistic one-pion exchange model. Parametric formulas of the isospin cross sections for one-pion production channels are discussed and are used to renormalize the model spectrum. Energy spectra for the deuteron related channels (NN yields dPi) are also described.

  11. Rainbow scattering in nuclear collisions

    SciTech Connect

    Berezhnoi-breve, Y.A.; Kuznichenko, A.V.; Onishchenko, G.M.; Pilipenko, V.V.

    1987-03-01

    The evolution of ideas about the rainbow phenomenon resulting from the refraction and reflection of light in water drops is briefly reviewed. The rainbow scattering of particles in quantum mechanics is treated on the basis of the semiclassical approximation, and the nuclear and Coulomb ''rainbows'' are discussed. Rainbow scattering of light ions by nuclei at energies Eapprox. >25--30 MeV/nucleon is considered. The results of theoretical analysis of experimental data on rainbow scattering are presented. The behavior of the nuclear part of the scattering phase shift deduced from experiment is discussed. The manifestation of rainbow scattering in quasielastic nuclear processes is considered.

  12. Nucleon Structure from Lattice QCD

    SciTech Connect

    Haegler, Philipp

    2011-10-24

    Hadron structure calculations in lattice QCD have seen substantial progress during recent years. We illustrate the achievements that have been made by discussing latest lattice results for a limited number of important observables related to nucleon form factors and generalized parton distributions. A particular focus is placed on the decomposition of the nucleon spin 1/2 in terms of quark spin and orbital angular momentum contributions. Results and limitations of the necessary chiral extrapolations based on ChPT will be briefly discussed.

  13. Inclusive Inelastic Electron Scattering from Nuclei

    SciTech Connect

    Fomin, Nadia

    2007-10-26

    Inclusive electron scattering from nuclei at large x and Q{sup 2} is the result of a reaction mechanism that includes both quasi-elastic scattering from nucleons and deep inelastic scattering from the quark consitituents of the nucleons. Data in this regime can be used to study a wide variety of topics, including the extraction of nuclear momentum distributions, the infiuence of final state interactions and the approach to y-scaling, the strength of nucleon-nucleon correlations, and the approach to x-scaling, to name a few. Selected results from the recent experiment E02-019 at the Thomas Jefferson National Accelerator Facility will be shown and their relevance discussed.

  14. Spin Structure of the Nucleon - Status and Recent Results

    SciTech Connect

    Kuhn, Sebastian; Chen, Jian-Ping; Leader, Elliot

    2009-07-01

    After the initial discovery of the so-called "spin crisis in the parton model" in the 1980s, a large set of polarization data in deep inelastic lepton-nucleon scattering was collected at labs like SLAC, DESY and CERN. More recently, new high precision data at large $x$ and in the resonance region have come from experiments at Jefferson Lab. These data, in combination with the earlier ones, allow us to study in detail the polarized parton densities, the $Q^2$ dependence of various moments of spin structure functions, the duality between deep inelastic and resonance data, and the nucleon structure in the valence quark region. Together with complementary data from HERMES, RHIC and COMPASS, we can put new limits on the flavor decomposition and the gluon contribution to the nucleon spin. In this report, we provide an overview of our present knowledge of the nucleon spin structure and give an outlook on future experiments. We focus in particular on the spin structure functions $g_

  15. Stylized features of single-nucleon momentum distributions

    NASA Astrophysics Data System (ADS)

    Ryckebusch, Jan; Vanhalst, Maarten; Cosyn, Wim

    2015-05-01

    Nuclear short-range correlations (SRC) typically manifest themselves in the tail parts of the single-nucleon momentum distributions. We propose an approximate practical method for computing those SRC contributions to the high-momentum parts. The framework adopted in this work is applicable throughout the nuclear mass table and corrects mean-field models for central, spin-isospin and tensor correlations by shifting the complexity induced by the SRC from the wave functions to the operators. It is argued that the expansion of these modified operators can be truncated to a low order. The proposed model can generate the SRC-related high-momentum tail of the single-nucleon momentum distribution. These are dominated by correlation operators acting on mean-field pairs with vanishing relative radial and angular-momentum quantum numbers. The proposed method explains the dominant role of proton-neutron pairs in generating the SRC and accounts for the magnitude and mass dependence of SRC as probed in inclusive electron scattering. It also provides predictions for the ratio of the amount of correlated proton-proton to proton-neutron pairs which are in line with the observations. In asymmetric nuclei, the correlations make the average kinetic energy for the minority nucleons larger than for the majority nucleons.

  16. Studying nucleon structure using an Electron-Ion Collider

    NASA Astrophysics Data System (ADS)

    Burton, Thomas; EIC Team

    2011-04-01

    The detailed composition of the spin of the nucleon remains unknown. Numerous experiments over the past two decades have shown that the spin of quarks alone cannot account for more than a third of the nucleon's spin. Proton-proton collisions at RHIC suggest a small gluon polarisation, but uncertainties remain large. An Electron-Ion Collider is proposed as future machine for precision studies of nucleon and nuclear structure. It will allow the study of the spin contribution from gluons and quarks, including their flavour decomposition, in heretofore unprecedented precision, and will access a much wider kinematic space than ever before, in particular extending to the currently unmeasured low Bjorken-x sea. The formalism of generalised parton distributions (GPDs), accessible for example via deeply-virtual Compton scattering, promises to allow study of the role of orbital angular momentum in nucleon spin. Furthermore, GPDs will extend understanding of parton distributions beyond the well-known one-dimensional PDFs, accessing three-dimensional structure via the impact parameter distributions of partons.

  17. Exploring Three Nucleon Forces in Lattice QCD

    SciTech Connect

    Doi, Takumi

    2011-10-21

    We study the three nucleon force in N{sub f} = 2 dynamical clover fermion lattice QCD, utilizing the Nambu-Bethe-Salpeter wave function of the three nucleon system. Since parity-odd two nucleon potentials are not available in lattice QCD at this moment, we develop a new formulation to extract the genuine three nucleon force which requires only the information of parity-even two nucleon potentials. In order to handle the extremely expensive calculation cost, we consider a specific three-dimensional coordinate configuration for the three nucleons. We find that the linear setup is advantageous, where nucleons are aligned linearly with equal spacings. The lattice calculation is performed with 16{sup 3}x32 configurations at {beta} = 1.95, m{sub {pi}} = 1.13 GeV generated by CP-PACS Collaboration, and the result of the three nucleon force in triton channel is presented.

  18. Recent lattice QCD results on nucleon structure

    SciTech Connect

    Konstantinos Orginos

    2006-07-01

    I review recent developments in lattice calculations of nucleon structure. In particular, I cover the calculations of nucleon matrix elements related to generalized parton distribution functions, structure functions and form factors.

  19. Quantum Monte Carlo calculations of neutron-alpha scattering.

    SciTech Connect

    Nollett, K. M.; Pieper, S. C.; Wiringa, R. B.; Carlson, J.; Hale, G. M.; Physics

    2007-07-13

    We describe a new method to treat low-energy scattering problems in few-nucleon systems, and we apply it to the five-body case of neutron-alpha scattering. The method allows precise calculations of low-lying resonances and their widths. We find that a good three-nucleon interaction is crucial to obtain an accurate description of neutron-alpha scattering.

  20. Quantum Monte Carlo Calculations of Neutron-{alpha} Scattering

    SciTech Connect

    Nollett, Kenneth M.; Pieper, Steven C.; Wiringa, R. B.; Carlson, J.; Hale, G. M.

    2007-07-13

    We describe a new method to treat low-energy scattering problems in few-nucleon systems, and we apply it to the five-body case of neutron-alpha scattering. The method allows precise calculations of low-lying resonances and their widths. We find that a good three-nucleon interaction is crucial to obtain an accurate description of neutron-alpha scattering.

  1. Measuring the scalar and vector polarizabilities of the nucleon using polarized photons and electrons

    SciTech Connect

    Miskimen, R.

    2013-11-07

    The next generation of Compton scattering experiments is underway at Mainz and other laboratories, where the goal is precision measurements of the scalar and vector polarizabilities of the nucleon using polarized photons and polarized targets. Results are presented for the first double polarized Compton scattering experiment utilizing a polarized proton target. Preliminary results are presented for the γ{sub E1E1} spin polarizability. Prospects are discussed for future nucleon polarizability measurements using a high intensity 300 MeV electron machine.

  2. Optimized Chiral Nucleon-Nucleon Interaction at Next-to-Next-to-Leading Order

    SciTech Connect

    Nazarewicz, Witold; Hagen, Gaute; Papenbrock, T.; Sarich, J.; Wild, S.; Baardsen, G.; Hjorth-Jensen, Morten; Jansen, G. R.

    2013-01-01

    We optimize the nucleon-nucleon interaction from chiral effective field theory at next-to-next-toleading order (NNLO). The resulting new chiral force NNLOopt yields 2 1 per degree of freedom for laboratory energies below approximately 125 MeV. In the A 3, 4 nucleon systems, the contributions of three-nucleon forces are smaller than for previous parametrizations of chiral interactions. We use NNLOopt to study properties of key nuclei and neutron matter, and we demonstrate that many aspects of nuclear structure can be understood in terms of this nucleon-nucleon interaction, without explicitly invoking three-nucleon forces.

  3. Gluon Spin Contribution to The Nucleon Spin

    NASA Astrophysics Data System (ADS)

    Arash, Firooz; Shahveh, Abolfazl; Taghavi-Shahri, Fateme

    2010-10-01

    We have calculated δg/ g in the nucleon at all measured kinematics. The smallness of δg/ g in the measured kinematics should not be interpreted as the the gluon contribution to the nucleon spin is small. In fact the first moment of gluon polarization in the nucleon, Δ g( Q2) can be sizable.

  4. Nucleonic coal detector with independent, hydropneumatic suspension

    NASA Technical Reports Server (NTRS)

    Jones, E. W.; Handy, K.

    1977-01-01

    The design of a nucleonic, coal interface detector which measures the depth of coal on the roof and floor of a coal mine is presented. The nucleonic source and the nucleonic detector are on independent hydropneumatic suspensions to reduce the measurement errors due to air gap.

  5. Nucleon Optical Potential in Brueckner Theory

    SciTech Connect

    Haider, Wasi

    2008-10-13

    Recent results of g-matrix calculation of the nucleon optical potential are presented and their predictions are compared with experimental data for Sn-isotopes. Corrections to spin-orbit part of the potential are discussed. Extension of Bethe's method to calculate three nucleon interaction effects in the nucleon optical potential is presented.

  6. Nucleon Resonances from FLIC Fermions

    SciTech Connect

    Derek Leinweber; J. Hedditch; Wally Melnitchouk; Anthony Williams

    2003-01-01

    The Fat Link Irrelevant Glover (FL1C) fermion action and its associated phenomenology is described. The scaling analysis indicates FLIC fermions provide a new form of nonperturbative O(a) improvement where near-continuum results are obtained at finite lattice spacing spin-1/2 and spin-3/2 , even and odd parity nucleon resonances are investigated.

  7. Three-nucleon problem: trinucleon bound states and trinucleon interactions

    SciTech Connect

    Friar, J.L.

    1985-01-01

    The assumptions underlying the formulation and solution of the Schroedinger equation for three nucleons in configuration space are reviewed, in conjunction with those qualitative aspects of the two-nucleon problem which are important. The geometrical features of the problem and the crucial role of the angular momentum barrier are developed. The boundary conditions for scattering are discussed qualitatively, and the Faddeev-Noyes equation is motivated. The method of splines and orthogonal collocation are shown to provide convenient techniques for generating numerical solutions. Properties of the many numerical solutions for the bound states and zero-energy scattering states are discussed. The evidence for three-body forces is reviewed, and the results of the recent calculations including such forces are discussed. The importance of electromagnetic interactions in the three-nucleon systems is motivated. Relativistic corrections and meson-exchange currents are discussed in the context of ''rules of scale'', and the pion-exchange currents of nonrelativistic order are derived. The experimental results for trinucleon electromagnetic interactions are reviewed, including recent tritium data. Conclusions are presented. 56 refs., 23 figs.

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

    NASA Astrophysics Data System (ADS)

    Webber, David M.; Daya Bay Collaboration

    2012-12-01

    The theory of neutrino oscillations explains changes in neutrino flavor, count rates, and spectra from solar, atmospheric, accelerator, and reactor neutrinos. These oscillations are characterized by three mixing angles and two mass-squared differences. The solar mixing angle, θ12, and the atmospheric mixing angle, θ23, have been well measured, but until recently the neutrino mixing angle θ13 was not well known. The Daya Bay experiment, located northeast of Hong Kong at the Guangdong Nuclear Power Complex in China, has made a precise measurement of electron antineutrino disappearance using six functionally-identical gadolinium-doped liquid scintillator-based detectors at three sites with distances between 364 and 1900 meters from six reactor cores. This proceeding describes the Daya Bay updated result, using 127 days of good run time collected between December 24, 2011 and May 11, 2012. For the far site, the ratio of the observed number of events to the expected number of events assuming no neutrino oscillation is 0.944±0.007(stat)±0.003(syst). A fit for θ13 in the three-neutrino framework yields sin2 2θ13=0.089±0.010(stat)±0.005(syst).

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

    NASA Astrophysics Data System (ADS)

    Li, Yu-Feng; Zhou, Ye-Ling

    2014-11-01

    We discuss reactor antineutrino oscillations with non-standard interactions (NSIs) at the neutrino production and detection processes. The neutrino oscillation probability is calculated with a parametrization of the NSI parameters by splitting them into the averages and differences of the production and detection processes respectively. The average parts induce constant shifts of the neutrino mixing angles from their true values, and the difference parts can generate the energy (and baseline) dependent corrections to the initial mass-squared differences. We stress that only the shifts of mass-squared differences are measurable in reactor antineutrino experiments. Taking Jiangmen Underground Neutrino Observatory (JUNO) as an example, we analyze how NSIs influence the standard neutrino measurements and to what extent we can constrain the NSI parameters. Long baseline reactor antineutrino experiments, such as KamLAND [10,11]. The aim of these experiments is to observe the slow oscillation with Δ21 and measure the corresponding oscillation parameters Δm212 and θ12. Short baseline reactor antineutrino experiments, such as Daya Bay [1-3], Double CHOOZ [4], RENO [5]. They are designed to observe the fast oscillation with Δ31 and Δ32 (or equivalently, Δee[3]) and measure the corresponding oscillation parameters Δmee2, θ13. Medium baseline reactor antineutrino experiments. They stand for the next generation experiments of reactor antineutrinos, with typical representatives of Jiangmen Underground Neutrino Observatory (JUNO) [12] and RENO-50 [13]. They can determine the neutrino mass ordering (m1antineutrino experiments. High-dimensional operators originating from new physics can contribute to the neutrino oscillation in the form of non-standard interactions (NSIs) [14

  10. New measurement of antineutrino oscillation with the full detector configuration at Daya Bay.

    PubMed

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

    2015-09-11

    We report a new measurement of electron antineutrino disappearance using the fully constructed Daya Bay Reactor Neutrino Experiment. The final two of eight antineutrino detectors were installed in the summer of 2012. Including the 404 days of data collected from October 2012 to November 2013 resulted in a total exposure of 6.9×10^{5} GW_{th}  ton days, a 3.6 times increase over our previous results. Improvements in energy calibration limited variations between detectors to 0.2%. Removal of six ^{241}Am-^{13}C radioactive calibration sources reduced the background by a factor of 2 for the detectors in the experimental hall furthest from the reactors. Direct prediction of the antineutrino signal in the far detectors based on the measurements in the near detectors explicitly minimized the dependence of the measurement on models of reactor antineutrino emission. The uncertainties in our estimates of sin^{2}2θ_{13} and |Δm_{ee}^{2}| were halved as a result of these improvements. An analysis of the relative antineutrino rates and energy spectra between detectors gave sin^{2}2θ_{13}=0.084±0.005 and |Δm_{ee}^{2}|=(2.42±0.11)×10^{-3}  eV^{2} in the three-neutrino framework. PMID:26406819

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

    NASA Astrophysics Data System (ADS)

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

    2012-08-01

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

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

    DOE PAGESBeta

    An, F. P.; Balantekin, A. B.; Band, H. R.; Bishai, M.; Blyth, S.; Butorov, I.; Cao, G. F.; Cao, J.; Cen, W. R.; Chan, Y. L.; et al

    2015-09-11

    We report a new measurement of electron antineutrino disappearance using the fully constructed Daya Bay Reactor Neutrino Experiment. The final two of eight antineutrino detectors were installed in the summer of 2012. Including the 404 days of data collected from October 2012 to November 2013 resulted in a total exposure of 6.9×105 GWth ton days, a 3.6 times increase over our previous results. Improvements in energy calibration limited variations between detectors to 0.2%. Removal of six 241Am- 13C radioactive calibration sources reduced the background by a factor of 2 for the detectors in the experimental hall furthest from the reactors.more » Direct prediction of the antineutrino signal in the far detectors based on the measurements in the near detectors explicitly minimized the dependence of the measurement on models of reactor antineutrino emission. The uncertainties in our estimates of 2sin2θ13 and |Δm2ee| were halved as a result of these improvements. An analysis of the relative antineutrino rates and energy spectra between detectors gave 2sin2θ13=0.084±0.005 and |Δm2ee|=(2.42±0.11)×10–3 eV2 in the three-neutrino framework.« less

  13. New Measurement of Antineutrino Oscillation with the Full Detector Configuration at Daya Bay

    NASA Astrophysics Data System (ADS)

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

    2015-09-01

    We report a new measurement of electron antineutrino disappearance using the fully constructed Daya Bay Reactor Neutrino Experiment. The final two of eight antineutrino detectors were installed in the summer of 2012. Including the 404 days of data collected from October 2012 to November 2013 resulted in a total exposure of 6.9 × 105 GWth ton days , a 3.6 times increase over our previous results. Improvements in energy calibration limited variations between detectors to 0.2%. Removal of six 241Am 241- 13C radioactive calibration sources reduced the background by a factor of 2 for the detectors in the experimental hall furthest from the reactors. Direct prediction of the antineutrino signal in the far detectors based on the measurements in the near detectors explicitly minimized the dependence of the measurement on models of reactor antineutrino emission. The uncertainties in our estimates of sin22 θ13 and |Δ mee 2| were halved as a result of these improvements. An analysis of the relative antineutrino rates and energy spectra between detectors gave sin22 θ13=0.084 ±0.005 and |Δ mee 2|=(2.42 ±0.11 )×10-3 eV2 in the three-neutrino framework.

  14. Fusion reactor nucleonics: status and needs

    SciTech Connect

    Lee, J.D.; Engholm, B.A.; Dudziak, D.J.; Haight, R.C.

    1980-01-01

    The national fusion technology effort has made a good start at addressing the basic nucleonics issues, but only a start. No fundamental nucleonics issues are seen as insurmountable barriers to the development of commercial fusion power. To date the fusion nucleonics effort has relied almost exclusively on other programs for nuclear data and codes. But as we progress through and beyond ETF type design studies the fusion program will need to support a broad based nucleonics effort including code development, sensitivity studies, integral experiments, data acquisition etc. It is clear that nucleonics issues are extremely important to fusion development and that we have only scratched the surface.

  15. Nuclear medium effects in structure functions of nucleon at moderate Q2

    NASA Astrophysics Data System (ADS)

    Haider, H.; Zaidi, F.; Sajjad Athar, M.; Singh, S. K.; Ruiz Simo, I.

    2015-11-01

    Recent experiments performed on inclusive electron scattering from nuclear targets have measured the nucleon electromagnetic structure functions F1 (x, Q2), F2 (x, Q2) and FL (x, Q2) in 12C, 27Al, 56Fe and 64Cu nuclei. The measurements have been done in the energy region of 1 GeV2 nucleon correlations, mesonic contributions from pion and rho mesons and shadowing effects. The calculations are performed in a local density approximation using a relativistic nucleon spectral function which includes nucleon correlations. The numerical results are compared with the recent experimental data from JLab and also with some earlier experiments.

  16. Enhancement and suppression of the neutrino-nucleon total cross section at ultrahigh energies

    NASA Astrophysics Data System (ADS)

    Jalilian-Marian, Jamal

    2003-09-01

    We argue that high gluon density effects at small x are important for the calculation of ultrahigh energy neutrino-nucleon cross sections due to the phenomenon of geometric scaling. We calculate the cross section for νN→μX, including high gluon density effects, using the all twist formalism of McLerran and Venugopalan and show that it can be related to the dipole nucleon cross section measured in deep inelastic scattering experiments. For neutrino energies of Eν˜1012 GeV, the geometric scaling region extends all the way up to Q2˜M2W. We show that geometric scaling can lead to an enhancement of the neutrino-nucleon total cross section by an order of magnitude compared to the leading twist cross section and discuss the implications for neutrino observatories. At extremely high energies, gluon saturation effects suppress the neutrino-nucleon total cross section and lead to its unitarization.

  17. Measurement of two- and three-nucleon short-range correlation probabilities in nuclei.

    PubMed

    Egiyan, K S; Dashyan, N B; Sargsian, M M; Strikman, M I; Weinstein, L B; Adams, G; Ambrozewicz, P; Anghinolfi, M; Asavapibhop, B; Asryan, G; Avakian, H; Baghdasaryan, H; Baillie, N; Ball, J P; Baltzell, N A; Batourine, V; Battaglieri, M; Bedlinskiy, I; Bektasoglu, M; Bellis, M; Benmouna, N; Biselli, A S; Bonner, B E; Bouchigny, S; Boiarinov, S; Bradford, R; Branford, D; Brooks, W K; Bültmann, S; Burkert, V D; Bultuceanu, C; Calarco, J R; Careccia, S L; Carman, D S; Carnahan, B; Chen, S; Cole, P L; Coltharp, P; Corvisiero, P; Crabb, D; Crannell, H; Cummings, J P; De Sanctis, E; DeVita, R; Degtyarenko, P V; Denizli, H; Dennis, L; Dharmawardane, K V; Djalali, C; Dodge, G E; Donnelly, J; Doughty, D; Dragovitsch, P; Dugger, M; Dytman, S; Dzyubak, O P; Egiyan, H; Elouadrhiri, L; Empl, A; Eugenio, P; Fatemi, R; Fedotov, G; Feuerbach, R J; Forest, T A; Funsten, H; Gavalian, G; Gevorgyan, N G; Gilfoyle, G P; Giovanetti, K L; Girod, F X; Goetz, J T; Golovatch, E; Gothe, R W; Griffioen, K A; Guidal, M; Guillo, M; Guler, N; Guo, L; Gyurjyan, V; Hadjidakis, C; Hardie, J; Hersman, F W; Hicks, K; Hleiqawi, I; Holtrop, M; Hu, J; Huertas, M; Hyde-Wright, C E; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Ito, M M; Jenkins, D; Jo, H S; Joo, K; Juengst, H G; Kellie, J D; Khandaker, M; Kim, K Y; Kim, K; Kim, W; Klein, A; Klein, F J; Klimenko, A; Klusman, M; Kramer, L H; Kubarovsky, V; Kuhn, J; Kuhn, S E; Kuleshov, S; Lachniet, J; Laget, J M; Langheinrich, J; Lawrence, D; Lee, T; Livingston, K; Maximon, L C; McAleer, S; McKinnon, B; McNabb, J W C; Mecking, B A; Mestayer, M D; Meyer, C A; Mibe, T; Mikhailov, K; Minehart, R; Mirazita, M; Miskimen, R; Mokeev, V; Morrow, S A; Mueller, J; Mutchler, G S; Nadel-Turonski, P; Napolitano, J; Nasseripour, R; Niccolai, S; Niculescu, G; Niculescu, I; Niczyporuk, B B; Niyazov, R A; O'Relly, G V; Osipenko, M; Ostrovidov, A I; Park, K; Pasyuk, E; Peterson, C; Pierce, J; Pivnyuk, N; Pocanic, D; Pogorelko, O; Polli, E; Pozdniakov, S; Preedom, B M; Price, J W; Prok, Y; Protopopescu, D; Qin, L M; Raue, B A; Riccardi, G; Ricco, G; Ripani, M; Ritchie, B G; Ronchetti, F; Rosner, G; Rossi, P; Rowntree, D; Rubin, P D; Sabatié, F; Salgado, C; Santoro, J P; Sapunenko, V; Schumacher, R A; Serov, V S; Sharabian, Y G; Shaw, J; Smith, E S; Smith, L C; Sober, D I; Stavinsky, A; Stepanyan, S; Stokes, B E; Stoler, P; Strauch, S; Suleiman, R; Taiuti, M; Taylor, S; Tedeschi, D J; Thompson, R; Tkabladze, A; Tkachenko, S; Todor, L; Tur, C; Ungaro, M; Vineyard, M F; Vlassov, A V; Weygand, D P; Williams, M; Wolin, E; Wood, M H; Yegneswaran, A; Yun, J; Zana, L; Zhang, J

    2006-03-01

    The ratios of inclusive electron scattering cross sections of 4He, 12C, and 56Fe to 3He have been measured at 1 < xB <. At Q2 > 1.4 GeV2, the ratios exhibit two separate plateaus, at 1.5 < xB < 2 and at xB > 2.25. This pattern is predicted by models that include 2- and 3-nucleon short-range correlations (SRC). Relative to A = 3, the per-nucleon probabilities of 3-nucleon SRC are 2.3, 3.1, and 4.4 times larger for A = 4, 12, and 56. This is the first measurement of 3-nucleon SRC probabilities in nuclei. PMID:16606174

  18. Photoproduction of Mesons on Quasi-Free Nucleons

    NASA Astrophysics Data System (ADS)

    Keshelashvili, I.

    2014-11-01

    The investigation of excited baryon states is important to understand the underling nature/symmetries of hadronic matter. Historically, the first nucleon excitation experiments have been done using charged pion and kaon secondary beams. Later the antiproton-proton scattering has also been involved. However, since the beginning of the 90's meson photoproduction reactions have been considered as a powerful tool in baryon spectroscopy. In this contribution, we overview our experimental programs conducted at the bremsstrahlung photon beams of the MAMI accelerator in Mainz and the ELSA accelerator in Bonn. The results are differential and total cross sections for photoproduction of light neutral mesons and of meson pairs off quasi-free nucleons bound in the deuteron (and sometimes other light nuclei). The scientific programs of this experiments also include single and double polarization measurements as well.

  19. Pion Total Cross Section in Nucleon - Nucleon Collisions

    NASA Technical Reports Server (NTRS)

    Norbury, John W.

    2009-01-01

    Total cross section parameterizations for neutral and charged pion production in nucleon - nucleon collisions are compared to experimental data over the projectile momentum range from threshold to 300 GeV. Both proton - proton and proton - neutron reactions are considered. Overall excellent agreement between parameterizations and experiment is found, except for notable disagreements near threshold. In addition, the hypothesis that the neutral pion production cross section can be obtained from the average charged pion cross section is checked. The theoretical formulas presented in the paper obey this hypothesis for projectile momenta below 500 GeV. The results presented provide a test of engineering tools used to calculate the pion component of space radiation.

  20. Chiral symmetry and the nucleon-nucleon interaction

    DOE PAGESBeta

    Machleidt, Ruprecht

    2016-04-20

    We review how nuclear forces emerge from low-energy quantum chromodynamics (QCD) via chiral effective field theory (EFT). During the past two decades, this approach has evolved into a powerful tool to derive nuclear two- and many-body forces in a systematic and model-independent way. We then focus on the nucleon-nucleon (NN) interaction and show in detail how, governed by chiral symmetry, the long- and intermediate-range of the NN potential builds up order by order. We proceed up to sixth order in small momenta, where convergence is achieved. Lastly, the final result allows for a full assessment of the validity of themore » chiral EFT approach to the NN interaction.« less

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

    NASA Astrophysics Data System (ADS)

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

    2015-11-01

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

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

    NASA Astrophysics Data System (ADS)

    Jones, Gordon

    2015-10-01

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

  3. Search for the disappearance of muon antineutrinos in the NuMI neutrino beam

    SciTech Connect

    Adamson, P.; Bock, G. J.; Boehnlein, D. J.; Bogert, D.; Childress, S.; Choudhary, B. C.; Hatcher, R.; Hylen, J.; James, C.; Jensen, D.; Koizumi, G.; Kreymer, A.; Lucas, P.; Moore, C. D.; Pahlka, R.; Plunkett, R. K.; Rebel, B.; Sharma, R.; Torretta, D.; Zwaska, R.

    2011-10-01

    We report constraints on antineutrino oscillation parameters that were obtained by using the two MINOS detectors to measure the 7% muon antineutrino component of the NuMI neutrino beam. In the Far Detector, we select 130 events in the charged-current muon antineutrino sample, compared to a prediction of 136.4{+-}11.7(stat){sub -8.9}{sup +10.2}(syst) events under the assumption |{Delta}m{sup 2}|=2.32x10{sup -3} eV{sup 2}, sin{sup 2}(2{theta})=1.0. Assuming no oscillations occur at the Near Detector baseline, a fit to the two-flavor oscillation approximation constrains |{Delta}m{sup 2}|<3.37x10{sup -3} eV{sup 2} at the 90% confidence level with sin{sup 2}(2{theta})=1.0.

  4. Spin Degrees of Freedom in Compton Scattering

    NASA Astrophysics Data System (ADS)

    Miskimen, R.

    2016-02-01

    The next generation of Compton scattering experiments is underway at Mainz and other laboratories, where the goal is precision measurements of the scalar and vector polarizabilities of the nucleon using polarized photons and polarized targets. Results are presented for the first double polarized Compton scattering experiment utilizing a polarized proton target. Preliminary results are presented for the four spin polarizabilities of the proton.

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

    NASA Astrophysics Data System (ADS)

    Sur, Bhaskar

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

  6. Kaon Production Off the Nucleon

    SciTech Connect

    Alam, M. Rafi; Athar, M. Sajjad; Simo, I. Ruiz; Vacas, M. J. Vicente

    2011-10-06

    We have studied the weak kaon production off the nucleon induced by neutrinos at the low and intermediate energies. The studied mechanisms are the main source of kaon production for neutrino energies up to 1.2 to 1.5 GeV for the various channels and the cross sections are large enough to be amenable to be measured by experiments such as MINERvA and T2K.

  7. Modeling Nucleon Generalized Parton Distributions

    SciTech Connect

    Radyushkin, Anatoly V.

    2013-05-01

    We discuss building models for nucleon generalized parton distributions (GPDs) H and E that are based on the formalism of double distributions (DDs). We find that the usual "DD+D-term'' construction should be amended by an extra term, generated by GPD E(x,\\xi). Unlike the $D$-term, this function has support in the whole -1 < x< 1 region, and in general does not vanish at the border points|x|=\\xi.

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

    SciTech Connect

    Adamson, P.; et al.

    2012-02-01

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

  9. Study of Electron Anti-neutrinos Associated with Gamma-Ray Bursts Using KamLAND

    NASA Astrophysics Data System (ADS)

    Asakura, K.; Gando, A.; Gando, Y.; Hachiya, T.; Hayashida, S.; Ikeda, H.; Inoue, K.; Ishidoshiro, K.; Ishikawa, T.; Ishio, S.; Koga, M.; Matsuda, S.; Mitsui, T.; Motoki, D.; Nakamura, K.; Obara, S.; Oki, Y.; Oura, T.; Shimizu, I.; Shirahata, Y.; Shirai, J.; Suzuki, A.; Tachibana, H.; Tamae, K.; Ueshima, K.; Watanabe, H.; Xu, B. D.; Yoshida, H.; Kozlov, A.; Takemoto, Y.; Yoshida, S.; Fushimi, K.; Piepke, A.; Banks, T. I.; Berger, B. E.; Fujikawa, B. K.; O'Donnell, T.; Learned, J. G.; Maricic, J.; Sakai, M.; Winslow, L. A.; Efremenko, Y.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Detwiler, J. A.; Enomoto, S.; Decowski, M. P.; KamLAND Collaboration

    2015-06-01

    We search for electron anti-neutrinos ({{\\bar{ν }}e}) from long- and short-duration gamma-ray bursts (GRBs) using data taken by the Kamioka Liquid Scintillator Anti-Neutrino Detector (KamLAND) from 2002 August to 2013 June. No statistically significant excess over the background level is found. We place the tightest upper limits on {{\\bar{ν }}e} fluence from GRBs below 7 MeV and place first constraints on the relation between {{\\bar{ν }}e} luminosity and effective temperature.

  10. How much does the MSW effect contribute to the reactor antineutrino anomaly?

    SciTech Connect

    Valdiviesso, G. A.

    2015-05-15

    It has been pointed out that there is a 5.7 ± 2.3 discrepancy between the predicted and the observed reactor antineutrino flux in very short baseline experiments. Several causes for this anomaly have been discussed, including a possible non-standard forth sterile neutrino. In order to quantify how much non-standard this anomaly really is, the standard MSW effect is reviewed. Knowing that reactor antineutrinos are produced in a dense medium (the nuclear fuel) and is usually detected in a less dense one (water, or scintillator), non-adiabatic effects are expected to happen, creating a difference between the creation and detection mixing angles.

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

    NASA Astrophysics Data System (ADS)

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

    2012-12-01

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

  12. Wigner-Thomas spin precession in polarized coincidence electronuclear scattering

    SciTech Connect

    Dmitrasinovic, V. )

    1993-05-01

    The role of the Wigner-Thomas precession in nucleon recoil polarization measurements in coincidence electron scattering processes is examined. The necessary formalism is developed within the framework of the Jacob-Wick method, and then applied to two processes: the pseudoscalar electroproduction off a nucleon and the deuteron two-body electrodisintegration.

  13. Comment on S-matrix parameterizations in NN-scattering

    SciTech Connect

    Mulders, P. J.

    1981-08-01

    The parameterization of the S-matrix used for the elastic part of the NN-scattering matrix in, for example, the Virginia Polytechnic Institute ineractive nucleon-nucleon program SAID, is not general enough to parameterize any 2 by 2 submatrix of a unitary matrix.

  14. OBE approximation of NN scattering in bag-model QCD

    NASA Astrophysics Data System (ADS)

    Bakker, B. L. G.; Maslow, J. N.; Weber, H. J.

    1981-09-01

    A partial-wave helicity-state analysis of nucleon-nucleon scattering is carried out in momentum space. Its basis is a one-boson and two-pion exchange amplitude from bag-model quantum chromodynamics. The resulting phase shifts and bound-state parameters of the deuteron are compared with data up to laboratory energies of ≈350 MeV.

  15. Pion content of the nucleon in polarized semi-inclusive DIS

    SciTech Connect

    Melnitchouk, W.; Thomas, A.W.

    1994-04-01

    An explicit pionic component of the nucleon may be identified by measuring polarized {Delta}{sup ++} fragments produced in deep-inelastic scattering (DIS) off polarized protons. The pion-exchange model predicts highly correlated polarizations of the {Delta}{sup ++} and target proton, in marked contrast with the competing diquark fragmentation process.

  16. Transition from hadronic to partonic interactions for a composite spin-1/2 model of a nucleon

    SciTech Connect

    Tjon, J. A.; Wallace, S. J.

    2000-12-01

    A simple model of a composite nucleon is developed in which a fermion and a boson, representing quark and diquark constituents of the nucleon, form a bound state owing to a contact interaction. Photon and pion couplings to the quark provide vertex functions for the photon and pion interactions with the composite nucleon. By a suitable choice of cutoff parameters of the model, realistic electromagnetic form factors are obtained for the proton. When a pseudoscalar pion-quark coupling is used, the pion-nucleon coupling is predominantly pseudovector. A virtual photopion amplitude is considered in which there are two types of contributions: hadronic contributions where the photon and pion interactions have an intervening propagator of the nucleon or its excited states, and contactlike contributions where the photon and pion interactions occur within a single vertex. At large Q, the contactlike contributions are dominant. The model nucleon exhibits scaling behavior in deep-inelastic scattering and the normalization of the parton distribution provides a rough normalization of the contactlike contributions. Calculations for the virtual photopion amplitude are performed using kinematics appropriate to its occurrence as a meson-exchange current in electron-deuteron scattering. The results suggest that the contactlike terms can dominate the meson-exchange current for Q>1GeV/c. There is a direct connection of the contactlike terms to the off-forward parton distributions of the model nucleon.

  17. Determination of electroweak parameters from the elastic scattering of muon neutrinos and antineutrinos on electrons

    SciTech Connect

    Ahrens, L.A.; Aronson, S.H.; Connolly, P.L.; Gibbard, B.G.; Murtagh, M.J.; Murtagh, S.J.; Terada, S.; White, D.H. ); Callas, J.L.; Cutts, D.; Diwan, M.V.; Hoftun, J.S.; Hughlock, B.W.; Lanou, R.E.; Shinkawa, T. ); Kurihara, Y. ); Amako, K.; Kabe, S. , Ibaraki-Ken 305 ); Nagashima, Y.; Suzuki, Y.; Tatsumi, S.; Yamaguchi, Y. ); Abe, K.; Beier, E.W.; Doughty, D.C.; Durkin, L.S.; Heagy, S.M.; Hurley, M.; Mann, A.K.; Newcomer, F.M.; Williams, H.H.; York, T. ); Hedin, D.; Marx, M.D.; Stern, E. )

    1990-06-01

    Total and differential cross sections for {nu}{sub {mu}}{ital e}{r arrow}{nu}{sub {mu}}{ital e} and {bar {nu}}{sub {mu}}{ital e}{r arrow}{bar {nu}}{sub {mu}}{ital e} are measured. Values for the model-independent neutral-current couplings of the electron are found to be {ital g}{sub {ital V}}={minus}0.107{plus minus}0.035(stat){plus minus}0.028(syst) and {ital g}{sub {ital A}}={minus}0.514{plus minus}0.023(stat){plus minus}0.028(syst). The electroweak mixing parameter sin{sup 2}{theta}{sub {ital W}} is determined to be 0.195{plus minus}0.018(stat){plus minus}0.013(syst). Limits are set for the charge radius and magnetic moment of the neutrino as ({l angle}{ital r}{sup 2}{r angle}){lt}0.24{times}10{sup {minus}32} cm{sup 2} and {ital f}{sub {mu}}{lt}0.85{times}10{sup {minus}9} Bohr magnetons, respectively.

  18. Chiral nucleon-nucleon forces in nuclear structure calculations

    NASA Astrophysics Data System (ADS)

    Coraggio, L.; Gargano, A.; Holt, J. W.; Itaco, N.; Machleidt, R.; Marcucci, L. E.; Sammarruca, F.

    2016-05-01

    Realistic nuclear potentials, derived within chiral perturbation theory, are a major breakthrough in modern nuclear structure theory, since they provide a direct link between nuclear physics and its underlying theory, namely the QCD. As a matter of fact, chiral potentials are tailored on the low-energy regime of nuclear structure physics, and chiral perturbation theory provides on the same footing two-nucleon forces as well as many-body ones. This feature fits well with modern advances in ab-initio methods and realistic shell-model. Here, we will review recent nuclear structure calculations, based on realistic chiral potentials, for both finite nuclei and infinite nuclear matter.

  19. Monte Carlo approaches to the few-nucleon continuum

    SciTech Connect

    Schiavilla, R. |; Carlson, J.; Wiringa, R.B.

    1994-08-01

    Variational and Green`s Function Monte Carlo methods are reviewed as applied to the study of the few-nucleon continuum at low- and intermediate-energies. Results recently obtained for the radiative and weak capture reactions n + {sup 3}He {yields} {sup 4}He + {gamma} and p + {sup 3}He {yields} {sup 4}He + e{sup +} + {nu}{sub e}, the {sup 5}He P-wave resonances, and the inclusive and exclusive electron scattering reactions on {sup 3}H and the helium isotopes are summarized.

  20. Three-body force in the three-nucleon system

    SciTech Connect

    Gibson, B.F.

    1986-01-01

    A brief summary of the symposium is presented. Three-nucleon force models are discussed, including the two-pion exchange potential, NN-..delta..N coupled-channels model, and phenomenological parametrization. Relevant experimental data and model calculations are discussed including form factors, binding energies, charge radii, and charge density for /sup 3/H and /sup 3/He. A calculation of the EMC effect for /sup 3/He is also made using Sasakawa's wave function and compared to experimental data obtained at SLAC. The paper ends with discussions of proton-deuteron scattering, investigations at intermediate energies, and QCD efforts to understand the three-body problem. (DWL)

  1. Gluon Contribution To The Nucleon Spin

    NASA Astrophysics Data System (ADS)

    Arash, Firooz; Taghavi-Shahri, Fatemeh; Shahveh, Abolfazl

    2011-07-01

    Gluon polarization in Nucleon is evaluated in the valon representation of hadrons. It is shown that although δg/g is small at the currently measured kinematics, it does not imply that the gluon contribution to the nucleon spin is small. In fact the first moment of gluon polarization in the nucleon, Δg(Q2), is sizable. We also notice that the majority of Δg is concentrated at around x = 0.08.

  2. Strangeness and meson-nucleon sigma terms

    SciTech Connect

    Dahiya, Harleen; Sharma, Neetika

    2011-10-21

    The chiral constituent quark model ({chi}CQM) has been extended to calculate the flavor structure of the nucleon through the meson-nucleon sigma terms which have large contributions from the quark sea and are greatly affected by chiral symmetry breaking and SU(3) symmetry breaking. The hidden strangeness component in the nucleon has also been investigated and its significant contribution is found to be consistent with the recent available experimental observations.

  3. A relativistic theory of few-nucleon systems

    SciTech Connect

    Alfred Stadler

    2010-12-01

    This talk provides an overview of recent results for two- and three-nucleon systems obtained within the framework of the covariant spectator theory (CST). The main features of two recently published models for the neutron–proton interaction, that fit the 2007 world data base containing several thousands of neutron-proton scattering data below 350 MeV with χ 2/N data ≈ 1, are presented. These one-boson-exchange models, called WJC-1 and WJC-2, have a considerably smaller number of adjustable parameters than are present in realistic nonrelativistic potentials. When applied to the three-nucleon bound state, the correct binding energy is obtained without additional three-body forces. First calculations of the electromagnetic form factors of helium-3 and the triton in complete impulse approximation also give very reasonable results. One can conclude that the CST yields a very efficient description of few-nucleon systems, in which the relativistic formulation of the dynamics is an essential element.

  4. Structure and spin of the nucleon

    NASA Astrophysics Data System (ADS)

    Avakian, H.

    2014-03-01

    Parton distribution functions, describing longitudinal momentum, helicity and transversity distributions of quarks and gluons, have been recently generalized to account also for transverse degrees of freedom. Two new sets of more general distributions, Transverse Momentum Distributions and Generalized Parton Distributions, were introduced to describe transverse momentum and space distributions of partons. Great progress has been made since then in measurements of different Single Spin Asymmetries (SSAs) in semi-inclusive and hard exclusive processes providing access to TMDs and GPDs, respectively. Facilities world-wide involved in studies of the 3D structure of nucleon include HERMES, COMPASS, BELLE, BaBar, Halls A, B, and C at JLab, and PHENIX and STAR at RHIC (BNL). TMD studies in the Drell-Yan process are also becoming an important part of the program of hadron scattering experiments. Studies of TMDs are also among the main driving forces of the JLab 12-GeV upgrade project, several of the forward upgrade proposals of STAR and PHENIX at RHIC, and future facilities, such as the Electron Ion Collider (EIC), FAIR in Germany, and NICA in Russia. In this contribution we present an overview of the latest developments in studies of parton distributions and discuss newly released results, ongoing activities, as well as some future measurements.

  5. Structure and Spin of the Nucleon

    SciTech Connect

    Avakian, Harut A.

    2014-03-01

    Parton distribution functions, describing longitudinal momentum, helicity and transversity distributions of quarks and gluons, have been recently generalized to account also for transverse degrees of freedom. Two new sets of more general distributions, Transverse Momentum Distributions and Generalized Parton Distributions, were introduced to describe transverse momentum and space distributions of partons. Great progress has been made since then in measurements of different Single Spin Asymmetries (SSAs) in semi-inclusive and hard exclusive processes providing access to TMDs and GPDs, respectively. Facilities world-wide involved in studies of the 3D structure of nucleon include HERMES, COMPASS, BELLE, BaBar, Halls A, B, and C at JLab, and PHENIX and STAR at RHIC (BNL). TMD studies in the Drell-Yan process are also becoming an important part of the program of hadron scattering experiments. Studies of TMDs are also among the main driving forces of the JLab 12-GeV upgrade project, several of the forward upgrade proposals of STAR and PHENIX at RHIC, and future facilities, such as the Electron Ion Collider (EIC), FAIR in Germany, and NICA in Russia. In this contribution we present an overview of the latest developments in studies of parton distributions and discuss newly released results, ongoing activities, as well as some future measurements.

  6. Extraction of In-Medium Nucleon-Nucleon Amplitude From Experiment

    NASA Technical Reports Server (NTRS)

    Tripathi, R. K.; Cucinotta, Francis A.; Wilson, John W.

    1998-01-01

    The in-medium nucleon-nucleon amplitudes are extracted from the available proton-nucleus total reaction cross sections data. The retrieval of the information from the experiment makes the estimate of reaction cross sections very reliable. Simple expressions are given for the in-medium nucleon-nucleon amplitudes for any system of colliding nuclei as a function of energy. Excellent agreement with experimental observations is demonstrated in the ion-nucleus interactions.

  7. Measurement of coherent production of π± in neutrino and antineutrino beams on carbon from Eν of 1.5 to 20 GeV

    DOE PAGESBeta

    Higuera, A.

    2014-12-23

    Neutrino-induced coherent charged pion production on nuclei ν(–)μA → μ±π∓A is a rare, inelastic interaction in which a small squared four-momentum |t| is transferred to the recoil nucleus, leaving it intact in the reaction. In the scintillator tracker of MINERvA, we remove events with evidence of particles from nuclear breakup and reconstruct |t| from the final-state pion and muon. In addition, we select low |t| events to isolate a sample rich in coherent candidates. By selecting low |t| events, we produce a model-independent measurement of the differential cross section for coherent scattering of neutrinos and antineutrinos on carbon. We findmore » poor agreement with the predicted kinematics in neutrino generators used by current oscillation experiments.« less

  8. Measurement of coherent production of π(±) in neutrino and antineutrino beams on carbon from Eν of 1.5 to 20 GeV.

    PubMed

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

    2014-12-31

    Neutrino-induced coherent charged pion production on nuclei νμA→μ(±)π(∓)A is a rare, inelastic interaction in which a small squared four-momentum |t| is transferred to the recoil nucleus, leaving it intact in the reaction. In the scintillator tracker of MINERvA, we remove events with evidence of particles from nuclear breakup and reconstruct |t| from the final-state pion and muon. We select low |t| events to isolate a sample rich in coherent candidates. By selecting low |t| events, we produce a model-independent measurement of the differential cross section for coherent scattering of neutrinos and antineutrinos on carbon. We find poor agreement with the predicted kinematics in neutrino generators used by current oscillation experiments. PMID:25615308

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

    PubMed

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

    2016-02-12

    This Letter reports a measurement of the flux and energy spectrum of electron antineutrinos from six 2.9 GWth nuclear reactors with six detectors deployed in two near (effective baselines 512 and 561 m) and one far (1579 m) underground experimental halls in the Daya Bay experiment. Using 217 days of data, 296 721 and 41 589 inverse β decay (IBD) candidates were detected in the near and far halls, respectively. The measured IBD yield is (1.55±0.04) ×10(-18)  cm(2) GW(-1) day(-1) or (5.92±0.14) ×10(-43)  cm(2) fission(-1). This flux measurement is consistent with previous short-baseline reactor antineutrino experiments and is 0.946±0.022 (0.991±0.023) relative to the flux predicted with the Huber-Mueller (ILL-Vogel) fissile antineutrino model. The measured IBD positron energy spectrum deviates from both spectral predictions by more than 2σ over the full energy range with a local significance of up to ∼4σ between 4-6 MeV. A reactor antineutrino spectrum of IBD reactions is extracted from the measured positron energy spectrum for model-independent predictions. PMID:26918980

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

    NASA Astrophysics Data System (ADS)

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

    2016-02-01

    This Letter reports a measurement of the flux and energy spectrum of electron antineutrinos from six 2.9 GWt h nuclear reactors with six detectors deployed in two near (effective baselines 512 and 561 m) and one far (1579 m) underground experimental halls in the Daya Bay experiment. Using 217 days of data, 296 721 and 41 589 inverse β decay (IBD) candidates were detected in the near and far halls, respectively. The measured IBD yield is (1.55 ±0.04 ) ×10-18 cm2 GW-1 day-1 or (5.92 ±0.14 ) ×10-43 cm2 fission-1 . This flux measurement is consistent with previous short-baseline reactor antineutrino experiments and is 0.946 ±0.022 (0.991 ±0.023 ) relative to the flux predicted with the Huber -Mueller (ILL -Vogel ) fissile antineutrino model. The measured IBD positron energy spectrum deviates from both spectral predictions by more than 2 σ over the full energy range with a local significance of up to ˜4 σ between 4-6 MeV. A reactor antineutrino spectrum of IBD reactions is extracted from the measured positron energy spectrum for model-independent predictions.

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

    NASA Astrophysics Data System (ADS)

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

    2016-03-01

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

  12. Beaming Neutrinos and Anti-neutrinos across the Earth to Disentangle Neutrino Mixing Parameters

    NASA Astrophysics Data System (ADS)

    Fargion, Daniele; D'Armiento, Daniele; Desiati, Paolo; Paggi, Paolo

    2012-10-01

    A result from MINOS seemed to indicate that the mass splitting and mixing angle of anti-neutrinos is different from that of neutrinos, suggesting a charge-parity-time (CPT) violation in the lepton sector. However, more recent MINOS data reduced the νμ-\\bar{\

  13. Photon emission in (anti)neutrino neutral current interactions with nuclei

    SciTech Connect

    Wang En; Alvarez-Ruso, Luis; Nieves, Juan

    2013-06-10

    Photon emission induced by E{sub {nu}}{approx} 1 GeV (anti)neutrino neutral current (NC) interactions with nuclei is studied with a dynamical microscopic model. This process is a relevant background for {nu}{sub e} appearance oscillation experiments. We find a strong reduction of the cross section due to nuclear effects.

  14. Measurement of the reactor antineutrino flux and spectrum at Daya Bay

    DOE PAGESBeta

    D. E. Jaffe; Bishai, M; Diwan, M.; Gill, R.; Hackenburg, R. W.; Hans, S.; Hu, L. M.; Jaffe, D. E.; Kettell, S. H.; Tang, W.; et al

    2016-02-12

    This Letter reports a measurement of the flux and energy spectrum of electron antineutrinos from six 2.9~GWth nuclear reactors with six detectors deployed in two near (effective baselines 512~m and 561~m) and one far (1,579 m) underground experimental halls in the Daya Bay experiment. Using 217 days of data, 296,721 and 41,589 inverse beta decay (IBD) candidates were detected in the near and far halls, respectively. The measured IBD yield is (1.55 ± 0.04) × 10–18 cm2/GW/day or (5.92 ± 0.14) × 10–43 cm2/fission. This flux measurement is consistent with previous short-baseline reactor antineutrino experiments and is 0.946 ± 0.022more » (0.991 ± 0.023) relative to the flux predicted with the Huber+Mueller (ILL+Vogel) fissile antineutrino model. The measured IBD positron energy spectrum deviates from both spectral predictions by more than 2σ over the full energy range with a local significance of up to ~4σ between 4-6 MeV. Furthermore, a reactor antineutrino spectrum of IBD reactions is extracted from the measured positron energy spectrum for model-independent predictions.« less

  15. Determination of the Sensitivity of the Antineutrino Probe for Reactor Core Monitoring

    SciTech Connect

    Cormon, S.; Fallot, M. Bui, V.-M.; Cucoanes, A.; Estienne, M.; Lenoir, M.; Onillon, A.; Shiba, T.; Yermia, F.; Zakari-Issoufou, A.-A.

    2014-06-15

    This paper presents a feasibility study of the use of the detection of reactor-antineutrinos (ν{sup ¯}{sub e}) for non proliferation purpose. To proceed, we have started to study different reactor designs with our simulation tools. We use a package called MCNP Utility for Reactor Evolution (MURE), initially developed by CNRS/IN2P3 labs to study Generation IV reactors. The MURE package has been coupled to fission product beta decay nuclear databases for studying reactor antineutrino emission. This method is the only one able to predict the antineutrino emission from future reactor cores, which don't use the thermal fission of {sup 235}U, {sup 239}Pu and {sup 241}Pu. It is also the only way to include off-equilibrium effects, due to neutron captures and time evolution of the fission product concentrations during a reactor cycle. We will present here the first predictions of antineutrino energy spectra from innovative reactor designs (Generation IV reactors). We will then discuss a summary of our results of non-proliferation scenarios involving the latter reactor designs, taking into account reactor physics constraints.

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

    NASA Astrophysics Data System (ADS)

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

    2016-03-01

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

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

    NASA Astrophysics Data System (ADS)

    Sonzogni, Alejandro; McCutchan, Elizabeth; Johnson, Timothy

    2015-10-01

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

  18. Nucleon effective E-mass in neutron-rich matter from the Migdal-Luttinger jump

    NASA Astrophysics Data System (ADS)

    Cai, Bao-Jun; Li, Bao-An

    2016-06-01

    The well-known Migdal-Luttinger theorem states that the jump of the single-nucleon momentum distribution at the Fermi surface is equal to the inverse of the nucleon effective E-mass. Recent experiments studying short-range correlations (SRC) in nuclei using electron-nucleus scatterings at the Jefferson National Laboratory (JLAB) together with model calculations constrained significantly the Migdal-Luttinger jump at saturation density of nuclear matter. We show that the corresponding nucleon effective E-mass is consequently constrained to M0*,E / M ≈ 2.22 ± 0.35 in symmetric nuclear matter (SNM) and the E-mass of neutrons is smaller than that of protons in neutron-rich matter. Moreover, the average depletion of the nucleon Fermi sea increases (decreases) approximately linearly with the isospin asymmetry δ according to κp/n ≈ 0.21 ± 0.06 ± (0.19 ± 0.08) δ for protons (neutrons). These results will help improve our knowledge about the space-time non-locality of the single-nucleon potential in neutron-rich nucleonic matter useful in both nuclear physics and astrophysics.

  19. Overview of nucleon form factor experiments with 12 GeV at Jefferson Lab

    NASA Astrophysics Data System (ADS)

    Cisbani, Evaristo

    2014-06-01

    Since the R. Hofstadter pioneering experiments in the '50s, the measurements of the electromagnetic space-like nucleon form factors (FF's) have been a precious source of information for the understanding of the internal structure of the nucleons. In the last 15 years, the polarization transfer experiments at the Thomas Jefferson National Accelerator Facility (JLab) have undermined our view of the mechanism of the electron scattering and renewed critical interest in the FF measurements. In the coming years, JLab, with its upgraded 12 GeV polarized, high intensity, electron beam combined to new targets and readout equipments, will offer unprecedented opportunities to extend the current proton and neutron FF's measurements to higher momentum transfer Q2 and to improve statistical and uncertainties at lower Q2, where the nucleon size can be accurately investigated. The measurements at high Q2 will provide also new insights on the elusive quark orbital angular momenta, will contribute to constraint two of the nucleon Generalized Parton Distributions that are expected to describe more consistently the nucleon structure, and in general will test the validity of quite a few fundamental nucleon models in a region of transition between perturbative and non perturbative regimes. A selection of the relevant properties of the FF's, and the main results of JLab are shortly reviewed; the new proposed and approved experiments on FF's at JLab are presented addressing some key details, the expected experimental achievements and the new equipment designed for them.

  20. Hard Break-Up of Two-Nucleons and QCD Dynamics of NN Interaction

    NASA Astrophysics Data System (ADS)

    Sargsian, Misak; Granados, Carlos

    2009-05-01

    We investigate hard photodisintegration of two nucleons from ^3He nucleus within the framework of hard rescattering model (HRM). In HRM a quark of one nucleon knocked-out by incoming photon rescatters with a quark of the other nucleon leading to the production of two nucleons with high relative momentum. HRM allows to express the amplitude of two-nucleon break-up reaction through the convolution of photon-quark scattering, NN hard scattering amplitude and nuclear spectral function which can be calculated using nonrelativistic ^3He wave function. HRM predicts several specific features for hard break-up reaction. First, the cross section will approximately scale as s-11. Also one predicts comparable or larger cross section for pp break up as compared to that of pn break-up, which is opposite to what is observed in low energy kinematics. Another result is the prediction of different spectator momentum dependencies of pp and pn break-up cross sections. This is due to the fact that same-helicity pp-component is strongly suppressed in the ground state wave function of ^3He. Due to this suppression HRM predicts significantly different asymmetries for the cross section of polarization transfer NN break-up reactions for circularly polarized photons. For the pp break-up this asymmetry is predicted to be zero while for the pn it is close to 23.

  1. Low Momentum Nucleon-Nucleon Interaction and Halo Nuclei

    NASA Astrophysics Data System (ADS)

    Kuo, T.; Bogner, S.

    A low-momentum effective nucleon-nucleon (NN) interaction Vlow-k is derived by integrating out the high momentum modes of modern realistic NN potentials VNN. The Kuo-Lee-Ratcliff folded diagram method together with the Andreozzi-Lee-Suzuki iteration method are employed to carry out the integration. Our Vlow-k is confined within a cut-off momentum Λ. The deuteron binding energy, low-energy phase shifts and half-on-shell T-matrix of VNN are all preserved by Vlow-k. For Λ within ˜ 2 fm-1, the Vlow-k derived from various NN potential models are very close to each other, although these models themselves are very different. Vlow-k is a smooth potential for Λ in the vicinity 2 fm-1, and appears to be suitable for being used directly as the shell model effective interaction, without first calculating the Brueckner G-matrix. Application of Vlow-k to halo nuclei is discussed.

  2. Realistic Low-Momentum Nucleon-Nucleon Potential

    NASA Astrophysics Data System (ADS)

    Kuo, T. T. S.; Bogner, S. K.; Coraggio, L.; Covello, A.; Itaco, N.

    2002-04-01

    A low-momentum nucleon-nucleon (NN) potential Vlow-k is derived from modern realistic NN potentials VNN by integrating out their high momentum modes. The Kuo-Lee-Ratcliff folded diagram method together with the Andreozzi-Lee-Suzuki iteration method is employed to carry out the integration. Our Vlow-k is confined within a cut-off momentum Λ, and it preserves the deuteron binding energy, low-energy phase shifts and low-momentum half-on-shell T-matrix of VNN. For Λ within ~ 2fm-1, the Vlow-k derived from various NN potential models are very close to each other, although these models themselves are very different. Vlow-k is a smooth potential for Λ in the vicinity 2fm-1, and appears to be suitable for being used directly as shell model effective interaction without first calculating the Brueckner G matrix. Preliminary shell-model calculations using Vlow-k have led to encouraging results.

  3. Hard probes of short-range nucleon-nucleon correlations

    SciTech Connect

    J. Arrington, D. W. Higinbotham, G. Rosner, M. Sargsian

    2012-10-01

    The strong interaction of nucleons at short distances leads to a high-momentum component to the nuclear wave function, associated with short-range correlations between nucleons. These short-range, high-momentum structures in nuclei are one of the least well understood aspects of nuclear matter, relating to strength outside of the typical mean-field approaches to calculating the structure of nuclei. While it is difficult to study these short-range components, significant progress has been made over the last decade in determining how to cleanly isolate short-range correlations in nuclei. We have moved from asking if such structures exist, to mapping out their strength in nuclei and studying their microscopic structure. A combination of several different measurements, made possible by high-luminosity and high-energy accelerators, coupled with an improved understanding of the reaction mechanism issues involved in studying these structures, has led to significant progress, and provided significant new information on the nature of these small, highly-excited structures in nuclei. We review the general issues related to short-range correlations, survey recent experiments aimed at probing these short-range structures, and lay out future possibilities to further these studies.

  4. The nucleon-nucleon potential in the chromodielectric soliton model

    NASA Astrophysics Data System (ADS)

    Koepf, W.; Wilets, L.; Pepin, S.; Stancu, F.

    The short and medium range parts of the nucleon-nucleon interaction are being studied in the framework of the chromodielectric soliton model. The model consists of current quarks, gluons in the abelian approximation, and a scalar sigma field which simulates the nonabelian interactions of the gluons and governs the medium through the dielectric function kappa(sigma). Absolute color confinement is effected by the vanishing of the dielectric in vacuum; this also removes the troublesome van der Waals problem. The authors distinguish between spatial confinement, which arises from the self energy of the quarks in medium (excluding MFA contributions), and color confinement which is effected through OGE in the MFA (including the corresponding self energy contributions). The static (adiabatic) energies are computed as a function of deformation (generalized bag separation) in a constrained MFA. Six quark molecular-type wave functions in all important space-spin-isospin-color configurations are included. The gluon propagator is solved in the deformed dielectric medium. The resultant Hamiltonian matrix is diagonalized. Dynamics are handled in the generator coordinate method, which leads to the Hill-Wheeler integral equation. In the present case, this yields a set of coupled equations corresponding to the various configurations. Although this can be approximated by a set of differential equations, they propose to solve the integral equations with some regularization scheme.

  5. Jet production in muon scattering at Fermilab E665

    SciTech Connect

    Salgado, C.W.; E665 Collaboration

    1993-11-01

    Measurements of multi-jet production rates from Muon-Nucleon and Muon-Nuclei scattering at Fermilab-E665 are presented. Jet rates are defined by the JADE clustering algorithm. Rates in Muon-Nucleon deep-inelastic scattering are compared to Monte Carlo model predictions. Preliminary results from jet production on heavy targets, in the shadowing region, show a higher suppression of two-forward jets as compared to one-forward jet production.

  6. Nucleon pairing in Sn isotopes

    NASA Astrophysics Data System (ADS)

    Imasheva, L.; Ishkhanov, B.; Stepanov, M.; Tretyakova, T.

    2016-01-01

    The systematics of excited states in Sn isotopes are discussed on basis of pairing interaction in nuclei. Nucleon paring leads to formation of excited states multiplets. The estimation of multiplet splitting based on experimental nuclear masses allows one to calculate the position of excited states with different seniority in δ-approximation. The wide systematics of the spectra of Sn isotopes gives a possibility to check the pairing interaction for different subshells and consider the multiplets of excited states in the neutron-rich isotopes far from stability.

  7. Modeling Nucleon Generalized Parton Distributions

    SciTech Connect

    Radyushkin, Anatoly V.

    2013-05-01

    We discuss building models for nucleon generalized parton distributions (GPDs) H and E that are based on the formalism of double distributions (DDs). We found that the usual "DD+D-term" construction should be amended by an extra term, xiE^1_+ (x,xi) built from the alpha/Beta moment of the DD e(Beta,alpha) that generates GPD E(x,xi). Unlike the D-term, this function has support in the whole -1< x<1 region, and in general does not vanish at the border points |x|=xi.

  8. Nucleon Structure from Lattice QCD

    SciTech Connect

    David Richards

    2007-09-05

    Recent advances in lattice field theory, in computer technology and in chiral perturbation theory have enabled lattice QCD to emerge as a powerful quantitative tool in understanding hadron structure. I describe recent progress in the computation of the nucleon form factors and moments of parton distribution functions, before proceeding to describe lattice studies of the Generalized Parton Distributions (GPDs). In particular, I show how lattice studies of GPDs contribute to building a three-dimensional picture of the proton, I conclude by describing the prospects for studying the structure of resonances from lattice QCD.

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

    SciTech Connect

    Grange, Joseph M.

    2013-01-01

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

  10. Di-hadron fragmentation and mapping of the nucleon structure

    NASA Astrophysics Data System (ADS)

    Pisano, Silvia; Radici, Marco

    2016-06-01

    The fragmentation of a colored parton directly into a pair of colorless hadrons is a non-perturbative mechanism that offers important insights into the nucleon structure. Di-hadron fragmentation functions can be extracted from semi-inclusive electron-positron annihilation data. They also appear in observables describing the semi-inclusive production of two hadrons in deep-inelastic scattering of leptons off nucleons or in hadron-hadron collisions. When a target nucleon is transversely polarized, a specific chiral-odd di-hadron fragmentation function can be used as the analyzer of the net density of transversely polarized quarks in a transversely polarized nucleon, the so-called transversity distribution. The latter can be extracted through suitable single-spin asymmetries in the framework of collinear factorization, thus in a much simpler framework with respect to the traditional one in single-hadron fragmentation. At subleading twist, the same chiral-odd di-hadron fragmentation function provides the cleanest access to the poorly known twist-3 parton distribution e( x) , which is intimately related to the mechanism of dynamical chiral symmetry breaking in QCD. When sensitive to details of transverse-momentum dynamics of partons, the di-hadron fragmentation functions for a longitudinally polarized quark can be connected to the longitudinal jet handedness to explore possible effects due to CP -violation of the QCD vacuum. In this review, we outline the formalism of di-hadron fragmentation functions, we discuss different observables where they appear and we present measurements and future worldwide plans.

  11. New measurement of antineutrino oscillation with the full detector configuration at Daya Bay

    SciTech Connect

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

    2015-09-11

    We report a new measurement of electron antineutrino disappearance using the fully constructed Daya Bay Reactor Neutrino Experiment. The final two of eight antineutrino detectors were installed in the summer of 2012. Including the 404 days of data collected from October 2012 to November 2013 resulted in a total exposure of 6.9×105 GWth ton days, a 3.6 times increase over our previous results. Improvements in energy calibration limited variations between detectors to 0.2%. Removal of six 241Am- 13C radioactive calibration sources reduced the background by a factor of 2 for the detectors in the experimental hall furthest from the reactors. Direct prediction of the antineutrino signal in the far detectors based on the measurements in the near detectors explicitly minimized the dependence of the measurement on models of reactor antineutrino emission. The uncertainties in our estimates of 2sin2θ13 and |Δm2ee| were halved as a result of these improvements. An analysis of the relative antineutrino rates and energy spectra between detectors gave 2sin2θ13=0.084±0.005 and |Δm2ee|=(2.42±0.11)×10–3 eV2 in the three-neutrino framework.

  12. Elastic proton-deuteron scattering at intermediate energies

    SciTech Connect

    Ramazani-Moghaddam-Arani, A.; Amir-Ahmadi, H. R.; Biegun, A.; Eslami-Kalantari, M.; Joulaeizadeh, L.; Kalantar-Nayestanaki, N.; Mardanpour, H.; Messchendorp, J. G.; Moeini, H.; Shende, S. V.; Bacher, A. D.; Bailey, C. D.; Stephenson, E. J.; Gasparic, I.; Kistryn, St.; Sworst, R.; Kozela, A.; Micherdzinska, A. M.; Stephan, E.

    2008-07-15

    Observables in elastic proton-deuteron scattering are sensitive probes of the nucleon-nucleon interaction and three-nucleon force effects. The present experimental database for this reaction is large, but contains a large discrepancy between data sets for the differential cross section taken at 135 MeV/nucleon by two experimental research groups. This article reviews the background of this problem and presents new data taken at Kernfysisch Versneller Instituute (KVI). Differential cross sections and analyzing powers for the {sup 2}H(p-vector,d)p and {sup 1}H(d-vector,d)p reactions at 135 MeV/nucleon and 65 MeV/nucleon, respectively, have been measured. The differential cross-section data differ significantly from previous measurements and consistently follow the energy dependence as expected from an interpolation of published data taken over a large range at intermediate energies.

  13. Pion-Skyrmion scattering: collective coordinates at work

    SciTech Connect

    Peskin, M.E.

    1985-06-01

    It is argued that the Skryme model, and more generally, the picture of the nucleon as a chiral soliton, can give a qualitatively correct picture of pion-nucleon scattering, considering both group-theoretic and more scheme-dependent results. The properties of the nucleon and its excited states in large-N quantum chromodynamics are discussed qualitatively. Then the pion-nucleon S-matrix is reduced. It is found that the model succeeds at the first level of calculation in producing many of the features of pion-nucleon scattering which are revealed by experiment, but that many aspects of the description need to be better understood, including the treatment of nonleading corrections near threshold and the inclusion of inelastic channels. 22 refs., 8 figs. (LEW)

  14. Insight into nucleon structure from generalized parton distributions

    SciTech Connect

    J.W. Negele; R.C. Brower; P. Dreher; R. Edwards; G. Fleming; Ph. Hagler; Th. Lippert; A.V.Pochinsky; D.B. Renner; D. Richards; K. Schilling; W. Schroers

    2004-03-01

    The lowest three moments of generalized parton distributions are calculated in full QCD and provide new insight into the behavior of nucleon electromagnetic form factors, the origin of the nucleon spin, and the transverse structure of the nucleon.

  15. Study of all Reaction Channels in Deuteron-Deuteron Scattering

    NASA Astrophysics Data System (ADS)

    Ramazani-Moghaddam-Arani, A.; Amir-Ahmadi, H. R.; Bacher, A. D.; Bailey, C. D.; Biegun, A.; Eslami-Kalantari, M.; Gašparić, I.; Joulaeizadeh, L.; Kalantar-Nayestanaki, N.; Kistryn, St.; Kozela, A.; Mardanpour, H.; Messchendorp, J. G.; Micherdzinska, A. M.; Moeini, H.; Shende, S. V.; Stephan, E.; Stephenson, E. J.; Sworst, R.

    Few-nucleon systems can be used as fundamental laboratories for studying details of the nuclear force effects. We performed a series of deuteron-deuteron scattering experiments at intermediate energies. The experiments exploited BINA and BBS experimental setups and polarized deuteron beams with kinetic energies of 65 and 90 MeV/nucleon. These experiments aim to measure differential cross sections, vector and tensor analyzing powers of all available reaction channels in deuteron-deuteron scattering. With these data we will provide a systematic database, which will be used to test present theoretical approximations and upcoming ab-initio calculations in four-nucleon system.

  16. Intrinsic charm content of the nucleon and charmness-nucleon sigma term

    NASA Astrophysics Data System (ADS)

    Duan, Shaorong; An, C. S.; Saghai, B.

    2016-06-01

    In the extended chiral constituent quark model, the intrinsic c c ¯ content of the nucleon is investigated. The probabilities of the quark-antiquark components in the nucleon wave functions are calculated by taking the nucleon to be admixtures of three- and five-quark components, with the relevant transitions handled via the 3P0 mechanism. Predictions for the probability of the c c ¯ in the nucleon wave function and the charmness-nucleon sigma term are presented. Our numerical results turn out to be consistent with the predictions from various other approaches reported in the literature.

  17. SANE Of Jefferson Lab: Spin Asymmetries on the Nucleon Experiment

    SciTech Connect

    Abdellah Ahmidouch

    2011-07-01

    The Spin Asymmetry on the Nucleon Experiment (SANE) at Jefferson Lab measures proton spin observables A1p, A2p and structure functions g1p and g2p over a broad range of Bjorken scaling variable x from 0.3 to 0.8, for four-momentum transfers ranging from 2.5 GeV2 to 6.5 GeV2. Inclusive double spin asymmetries were measured by scattering 4.7 and 5.9-GeV longitudinally polarized electron beam off a polarized solid NH3 target, in both parallel and near-perpendicular configuration. Scattered electrons were detected using a novel non-magnetic detector array with 194-msr acceptance. This paper presents the physics motivation for the experiment, the detector performance, and the latest status of the ongoing data analysis.

  18. SANE Of Jefferson Lab: Spin Asymmetries on the Nucleon Experiment

    SciTech Connect

    Ahmidouch, Abdellah

    2011-07-15

    The Spin Asymmetry on the Nucleon Experiment (SANE) at Jefferson Lab measures proton spin observables A{sub 1}{sup p}, A{sub 2}{sup p} and structure functions g{sub 1}{sup p} and g{sub 2}{sup p} over a broad range of Bjorken scaling variable x from 0.3 to 0.8, for four-momentum transfers ranging from 2.5 GeV{sup 2} to 6.5 GeV{sup 2}. Inclusive double spin asymmetries were measured by scattering 4.7 and 5.9-GeV longitudinally polarized electron beam off a polarized solid NH{sub 3} target, in both parallel and near-perpendicular configuration. Scattered electrons were detected using a novel non-magnetic detector array with 194-msr acceptance. This paper presents the physics motivation for the experiment, the detector performance, and the latest status of the ongoing data analysis.

  19. Nucleon interaction data bases for background estimates

    NASA Technical Reports Server (NTRS)

    Wilson, John W.; Townsend, Lawrence W.

    1989-01-01

    Nucleon interaction data bases available in the open literature are examined for potential use in a recently developed nucleon transport code. Particular attention is given to secondary particle penetration and the multiple charged ion products. A brief description of the transport algorithm is given.

  20. Orbital angular momentum in the nucleon

    SciTech Connect

    Garvey, Gerald T.

    2010-05-15

    Analysis of the measured value of the integrated d-bar-u-bar asymmetry (I{sub fas} = 0.147 +- 0.027) in the nucleon show it to arise from nucleon fluctuations into baryon plus pion. Requiring angular momentum conservation in these fluctuations shows the associated orbital angular momentum is equal to the value of the flavor asymmetry.

  1. In-medium short-range dynamics of nucleons: Recent theoretical and experimental advances

    NASA Astrophysics Data System (ADS)

    Atti, Claudio Ciofi degli

    2015-08-01

    The investigation of in-medium short-range dynamics of nucleons, usually referred to as the study of short-range correlations (SRCs), is a key issue in nuclear and hadronic physics. As a matter of fact, even in the simplified assumption that the nucleus could be described as a system of protons and neutrons interacting via effective nucleon-nucleon (NN) interactions, several non trivial problems arise concerning the description of in-medium (NN short-range dynamics, namely: (i) the behavior of the NN interaction at short inter-nucleon distances in medium cannot be uniquely constrained by the experimental NN scattering phase shifts due to off-shell effects; (ii) by rigorous renormalization group (RG) techniques entire families of phase equivalent interactions differing in the short-range part can be derived; (iii) the in-medium NN interaction may be, in principle, different from the free one; (iv) when the short inter-nucleon separation is of the order of the nucleon size, the question arises of possible effects from quark and gluon degrees of freedom. For more than fifty years, experimental evidence of SRCs has been searched by means of various kinds of nuclear reactions, without however convincing results, mainly because the effects of SRCs arise from non observable quantities, like, e.g., the momentum distributions, and have been extracted from observable cross sections where short- and long-range effects, effects from nucleonic and non nucleonic degrees of freedom, and effects from final state interaction, could not be unambiguously separated out. Recent years, however, were witness of new progress in the field: from one side, theoretical and computational progress has allowed one to solve ab initio the many-nucleon non relativistic Schrödinger equation in terms of realistic NN interactions, obtaining realistic microscopic wave functions, unless the case of parametrized wave functions used frequently in the past, moreover the development of advanced treatments

  2. GPDs of the nucleons and elastic scattering at high energies

    NASA Astrophysics Data System (ADS)

    Selyugin, O. V.

    2012-07-01

    Taking into account the electromagnetic and gravitational form factors, calculated from a new set of t-dependent GPDs, a new model is built. The real part of the hadronic amplitude is determined only through complex s. In the framework of this model the quantitative description of all existing experimental data at 52.8 ≤sqrt{s} ≤ 1960 GeV, including the Coulomb range and large momentum transfers (0.0008≤| t|≤9.75 GeV2), is obtained with only three fitting high energy parameters. The comparison with the preliminary data of the TOTEM Collaboration at an energy of 7 TeV is made.

  3. Polarized light ions and spectator nucleon tagging at EIC

    SciTech Connect

    Guzey, Vadim; Higinbotham, Dougas W.; Hyde, Charles; Nadel-Turonski, Pawel A.; Park, Kijun; Sargsian, Misak M.; Strikman, Mark; Weiss, Christian

    2014-10-01

    The neutron's deep-inelastic structure functions provide essential information for the flavor separation of the nucleon parton densities, the nucleon spin decomposition, and precision studies of QCD phenomena in the flavor-singlet and nonsinglet sectors. Traditional inclusive measurements on nuclear targets are limited by dilution from scattering on protons, Fermi motion and binding effects, final-state interactions, and nuclear shadowing at x ll 0.1. An Electron-Ion Collider (EIC) would enable next-generation measurements of neutron structure with polarized deuteron beams and detection of forward-moving spectator protons over a wide range of recoil momenta (0 < p(R) < several 100MeV in the nucleus rest frame). The free neutron structure functions could be obtained by extrapolating the measured recoil momentum distributions to the on-shell point. The method eliminates nuclear modifications and can be applied to polarized scattering, as well as to semi-inclusive and exclusive final states. We review the prospects for neutron structure measurements with spectator tagging at EIC, the status of R&D efforts, and the accelerator and detector requirements.

  4. Two-photon exchange in electron-trinucleon elastic scattering

    NASA Astrophysics Data System (ADS)

    Kobushkin, A. P.; Timoshenko, Ju. V.

    2013-10-01

    We discuss two-photon exchange (TPE) in elastic electron scattering off the trinucleon systems, 3He and 3H. The calculations are done in the semirelativistic approximation with the trinucleon wave functions obtained with the Paris and CD-Bonn nucleon-nucleon potentials. An applicability area of the model is wide enough and includes the main part of kinematical domain where experimental data exist. All three TPE amplitudes (generalized form factors) for electron 3He elastic scattering are calculated. We find that the TPE amplitudes are a few times more significant in the scattering of electrons off 3He then in the electron-proton scattering.

  5. Nucleon and heavy-ion total and absorption cross section for selected nuclei

    NASA Technical Reports Server (NTRS)

    Wilson, J. W.; Costner, C. M.

    1975-01-01

    Approximate solutions of the coupled-channel equations for high-energy composite particle scattering are obtained and are applied to the nuclear scattering problem. Relationships between several approximation procedures are established and discussed. The eikonal formalism is used with a small-angle approximation to calculate the coherent elastic scattered amplitude from which total and absorption cross sections are derived. Detailed comparisons with nucleon-nucleus experiments show agreement within 5 percent except at lower energies where the eikonal approximation is of questionable accuracy. Even at these lower energies, agreement is within 15 percent. Tables of cross sections required for cosmic heavy-ion transport and shielding studies are presented.

  6. Overview of nucleon structure studies

    SciTech Connect

    Marc Vanderhaeghen

    2007-06-08

    A brief overview of the recent activity in the measurement of the elastic electromagnetic proton and neutron form factors is presented. It is discussed how the quality of the data has been greatly improved by performing double polarization experiments, and the role of two-photon exchange processes will be highlighted. The spatial information on the quark charge distribibutions in the nucleon resulting from the form factors measurements will be discussed, as well as the steady rate of improvements made in the lattice QCD calculations. It is discussed how generalized parton distributions have emerged as a unifying theme in hadron physics linking the spatial densities extracted from form factors with the quark momentum distribution information residing in quark structure functions. The recent progress in the electromagnetic excitation of the $\\Delta(1232)$ resonance will also briefly be discussed.

  7. Studies of the nucleon structure in back-to-back SIDIS

    NASA Astrophysics Data System (ADS)

    Avakian, H.

    2016-03-01

    The Deep Inelastic Scattering (DIS) proved to be a great tool in testing of the theory of strong interactions, which was a major focus in last decades. Semi-Inclusive DIS (SIDIS), with detection of an additional hadron allowed first studies of 3D structure of the nucleon, moving the main focus from testing the QCD to understanding of strong interactions and quark gluon dynamics to address a number of puzzles accumulated in recent years. Detection of two hadrons in SIDIS, which is even more complicated, provides access to details of quark gluon interactions inaccessible in single-hadron SIDIS, providing a new avenue to study the complex nucleon structure. Large acceptance of the Electron Ion Collider, allowing detection of two hadrons, produced back-to-back in the current and target fragmentation regions, combined with clear separation of two regions, would provide a unique possibility to study the nucleon structure in target fragmentation region, and correlations of target and current fragmentation regions.

  8. Nucleon and nucleon-pair momentum distributions in A≤12 nuclei

    DOE PAGESBeta

    Wiringa, Robert B.; Schiavilla, Rocco; Pieper, Steven C.; Carlson, Joseph A.

    2014-02-10

    We report variational Monte Carlo calculations of single-nucleon momentum distributions for A≤12 nuclei and nucleon-pair and nucleon-cluster momentum distributions for A≤8. The wave functions have been generated for a Hamiltonian containing the Argonne ν18 two-nucleon and Urbana X three-nucleon potentials. The single-nucleon and nucleon-pair momentum distributions exhibit universal features attributable to the one-pion-exchange tensor interaction The single-nucleon distributions are broken down into proton and neutron components and spin-up and spin-down components where appropriate. The nucleon-pair momentum distributions are given separately for pp and pn pairs. The nucleon-cluster momentum distributions include dp in 3He, tp and dd in S4He, αd inmore » 6Li,αt in 7Li, and αα in 8Be. Detailed tables are provided on-line for download.« less

  9. Nucleon and nucleon-pair momentum distributions in A≤12 nuclei

    SciTech Connect

    Wiringa, Robert B.; Schiavilla, Rocco; Pieper, Steven C.; Carlson, Joseph A.

    2014-02-10

    We report variational Monte Carlo calculations of single-nucleon momentum distributions for A≤12 nuclei and nucleon-pair and nucleon-cluster momentum distributions for A≤8. The wave functions have been generated for a Hamiltonian containing the Argonne ν18 two-nucleon and Urbana X three-nucleon potentials. The single-nucleon and nucleon-pair momentum distributions exhibit universal features attributable to the one-pion-exchange tensor interaction The single-nucleon distributions are broken down into proton and neutron components and spin-up and spin-down components where appropriate. The nucleon-pair momentum distributions are given separately for pp and pn pairs. The nucleon-cluster momentum distributions include dp in 3He, tp and dd in S4He, αd in 6Li,αt in 7Li, and αα in 8Be. Detailed tables are provided on-line for download.

  10. Solutions of the Schrodinger Equation Using Approximate Nucleon-Nucleon and Lambda-Nucleon Potentials.

    ERIC Educational Resources Information Center

    Banerjee, S. N.; Chakraborty, S. N.

    1980-01-01

    Presents the outline of an approach related to the teaching of the chapter on bound and scattering states in a short-range potential, which forms a standard part of an undergraduate quantum mechanics course or nuclear physics course. (HM)

  11. First measurement of neutrino and antineutrino coherent charged pion production on argon

    SciTech Connect

    Acciarri, R.; Adams, C.; Asaadi, J.; Baller, B.; Bolton, T.; Bromberg, C.; Cavanna, F.; Church, E.; Edmunds, D.; Ereditato, A.; Farooq, S.; Fleming, B.; Greenlee, H.; Hatcher, R.; Horton-Smith, G.; James, C.; Klein, E.; Lang, K.; Laurens, P.; Mehdiyev, R.; Page, B.; Palamara, O.; Partyka, K.; Rameika, G.; Rebel, B.; Santos, E.; Schukraft, A.; Soderberg, M.; Spitz, J.; Szelc, A.  M.; Weber, M.; Yang, T.; Zeller, G. P.

    2014-12-23

    We report on the first cross section measurements for charged current coherent pion production by neutrinos and antineutrinos on argon. These measurements are performed using the ArgoNeuT detector exposed to the NuMI beam at Fermilab. The cross sections are measured to be 2.6 +1.2-1.0 (stat)+0.3-0.4(syst) × 10⁻³⁸cm² / Ar for neutrinos at a mean energy of 9.6 GeV and 5.5+2.6-2.1(stat)+0.6-0.7(syst) × 10⁻³⁹ cm² / Ar for antineutrinos at a mean energy of 3.6 GeV.

  12. Neutron β -decay as the origin of IceCube's PeV (anti)neutrinos

    NASA Astrophysics Data System (ADS)

    Anchordoqui, Luis A.

    2015-01-01

    Motivated by the indications of a possible deficit of muon tracks in the first three-year equivalent data set of IceCube we investigate the possibility that the astrophysical (anti)neutrino flux (in the PeV energy range) could originate from β -decay of relativistic neutrons. We show that to accommodate IceCube observations it is necessary that only about 1% to 10% of the emitted cosmic rays in the energy decade 108.5≲ECR/GeV ≲109.5 , yielding antineutrinos on Earth (1 05.5≲Eν ¯/GeV ≲1 06.5 ), are observed. Such a strong suppression can be explained assuming magnetic shielding of the secondary protons which diffuse in extragalactic magnetic fields of strength 10 ≲B /nG ≲100 and coherence length ≲Mpc .

  13. First measurement of neutrino and antineutrino coherent charged pion production on argon

    DOE PAGESBeta

    Acciarri, R.; Adams, C.; Asaadi, J.; Baller, B.; Bolton, T.; Bromberg, C.; Cavanna, F.; Church, E.; Edmunds, D.; Ereditato, A.; et al

    2014-12-23

    We report on the first cross section measurements for charged current coherent pion production by neutrinos and antineutrinos on argon. These measurements are performed using the ArgoNeuT detector exposed to the NuMI beam at Fermilab. The cross sections are measured to be 2.6 +1.2-1.0 (stat)+0.3-0.4(syst) × 10⁻³⁸cm² / Ar for neutrinos at a mean energy of 9.6 GeV and 5.5+2.6-2.1(stat)+0.6-0.7(syst) × 10⁻³⁹ cm² / Ar for antineutrinos at a mean energy of 3.6 GeV.

  14. First measurement of neutrino and antineutrino coherent charged pion production on argon.

    PubMed

    Acciarri, R; Adams, C; Asaadi, J; Baller, B; Bolton, T; Bromberg, C; Cavanna, F; Church, E; Edmunds, D; Ereditato, A; Farooq, S; Fleming, B; Greenlee, H; Hatcher, R; Horton-Smith, G; James, C; Klein, E; Lang, K; Laurens, P; Mehdiyev, R; Page, B; Palamara, O; Partyka, K; Rameika, G; Rebel, B; Santos, E; Schukraft, A; Soderberg, M; Spitz, J; Szelc, A M; Weber, M; Yang, T; Zeller, G P

    2014-12-31

    We report on the first cross section measurements for charged current coherent pion production by neutrinos and antineutrinos on argon. These measurements are performed using the ArgoNeuT detector exposed to the NuMI beam at Fermilab. The cross sections are measured to be 2.6(-1.0)(+1.2)(stat)(-0.4)(+0.3)(syst)×10(-38)  cm(2)/Ar for neutrinos at a mean energy of 9.6 GeV and 5.5(-2.1)(+2.6)(stat)(-0.7)(+0.6)(syst)×10(-39)  cm(2)/Ar for antineutrinos at a mean energy of 3.6 GeV. PMID:25615307

  15. First measurement of neutrino and antineutrino coherent charged pion production on argon

    DOE PAGESBeta

    Acciarri, R.

    2015-01-20

    In this study, we report on the first cross section measurements for charged current coherent pion production by neutrinos and antineutrinos on argon. These measurements are performed using the ArgoNeuT detector exposed to the NuMI beam at Fermilab. The cross sections are measured to be 2.6 +1.2-1.0 (stat)+0.3-0.4(syst) x 10-38 cm2/Ar for neutrinos at a mean energy of 9.6 GeV and 5.5+2.6-2.1(stat)+0.6-0.7(syst) x 10-39 cm2/Ar for antineutrinos at a mean energy of 3.6 GeV.

  16. New anti-neutrino cross-section results from MiniBooNE

    SciTech Connect

    Grange, Joseph; Dharmapalan, Ranjan

    2015-05-15

    The first measurements of antineutrino charged-current quasielastic (ν{sup ¯}{sub μ} CCQE, ν{sub µ} + N → µ{sup +} + N{sup ′}) and neutral-current elastic (ν{sup ¯}{sub μ} NCE, ν{sub µ} + N → ν{sub µ} + N) cross sections with 〈E{sub ν{sup ¯}}〉<1 GeV are presented. To maximize the precision of these measurements, many data-driven background measurements were executed, including a first demonstration of charge separation using a non-magnetized detector. Apart from extending our knowledge of antineutrino interactions by probing a new energy range, these measurements constrain signal and background processes for current and future neutrino oscillation experiments and also carry implications for intra-nuclear interactions.

  17. Experimental spectrum of reactor antineutrinos and spectra of main fissile isotopes

    SciTech Connect

    Sinev, V. V.

    2013-05-15

    Within the period between the years 1988 and 1990, the spectrum of positrons from the inverse-beta-decay reaction on a proton was measured at the Rovno atomic power plant in the course of experiments conducted there. The measured spectrum has the vastest statistics in relation to other neutrino experiments at nuclear reactors and the lowest threshold for positron detection. An experimental reactor-antineutrino spectrum was obtained on the basis of this positron spectrum and was recommended as a reference spectrum. The spectra of individual fissile isotopes were singled out from the measured antineutrino spectrum. These spectra can be used to analyze neutrino experiments performed at nuclear reactors for various compositions of the fuel in the reactor core.

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

    SciTech Connect

    Adamson, P.; Bock, G. J.; Boehnlein, D. J.; Bogert, D.; Childress, S.; Harris, D.; Hatcher, R.; Hylen, J.; James, C.; Jensen, D.; Koizumi, G.; Kreymer, A.; Lucas, P.; Moore, C. D.; Morfin, J.; Plunkett, R. K.; Rameika, R. A.; Rebel, B.; Saoulidou, N.; Shanahan, P.

    2010-04-01

    The energy dependence of the neutrino-iron and antineutrino-iron inclusive charged-current cross sections and their ratio have been measured using a high-statistics sample with the MINOS near detector exposed to the NuMI beam from the main injector at Fermilab. Neutrino and antineutrino fluxes were determined using a low hadronic energy subsample of charged-current events. We report measurements of {nu}-Fe ({nu}-Fe) cross section in the energy range 3-50 GeV (5-50 GeV) with precision of 2%-8% (3%-9%) and their ratio which is measured with precision 2%-8%. The data set spans the region from low energy, where accurate measurements are sparse, up to the high-energy scaling region where the cross section is well understood.

  19. Confining quark condensate model of the nucleon.

    SciTech Connect

    Frank, Michael; Tandy, Peter

    1992-07-01

    We obtain a mean-field solution for the nucleon as a quark-meson soliton obtained from the action of the global color-symmetry model of QCD. All dynamics is generated from an effective interaction of quark currents. At the quark-meson level there are two novel features: (1) absolute confinement is produced from the space-time structure of the dynamical self-energy in the vacuum quark propagator; and (2) the related scalar meson field is an extended q-barq composite that couples nonlocally to quarks. The influence of these features upon the nucleon mass contributions and other nucleon properties is presented.

  20. Double Chooz and the search for short range anti-neutrino oscillations

    NASA Astrophysics Data System (ADS)

    Hartmann, Francis X.

    2009-06-01

    The Double Chooz Experiment seeks to search for short range antineutrino oscillations from the nuclear reactors at the Chooz Nuclear Power Station operated by Electricite de France in Northeastern France. The measurements are of interest to constraining the value for θ13 in current neutrino oscillation models. New scintillator types based on beta-diketone and pH stabilized carboxylic acid chemistry are described. New results from the study of these scintillators in the context of the detector design are reported.

  1. Spin Correlation Parameter Cyy of p + 3He Elastic Backward Scattering at Intermediate Energy

    NASA Astrophysics Data System (ADS)

    Shimizu, Y.; Hatanaka, K.; Adachi, T.; Itoh, K. F. K.; Kawabata, T.; Kudoh, T.; Ohira, H. M. H.; Okamura, H.; Sagara, K.; Sasamoto, Y. S. Y.; Yoshida, Y. S. H. P.; Suda, K.; Tomiyama, Y. T. A. T. M.; Uesaka, M. U. T.; Wakasa, T.; Wakui, T.

    2005-08-01

    It is possible to use nucleon-nucleus scattering as a probe of the spin structure of nuclei, since target related observables are extremely sensitive to small spin-dependent parts of the target wave function. In addition, one can gain information about the nucleon-nucleus reaction mechanism, the spin dependence of the nucleon-nucleon interaction in the nuclear medium, and off-shell behavior of the nucleon-nucleon amplitudes. For 3He(p,3He)p elastic backward scattering (EBS), only a small amount of data exists for the differential cross-section and none exists for spin-dependent observables. We have developed a spin-exchange polarised 3He target and measured the spin correlation parameter Cyy at 200, 300, and 400 MeV.

  2. Spin Correlation Parameter Cyy of p + 3He Elastic Backward Scattering at Intermediate Energy

    NASA Astrophysics Data System (ADS)

    Shimizu, Y.; Hatanaka, K.; Kobushkin, A. P.; Adachi, T.; Fujita, K.; Itoh, K.; Kawabata, T.; Kudoh, T.; Matsubara, H.; Ohira, H.; Okamura, H.; Sagara, K.; Sakemi, Y.; Sasamoto, Y.; Shimbara, Y.; Yoshida, H. P.; Suda, K.; Tameshige, Y.; Tamii, A.; Tomiyama, M.; Uchida, M.; Uesaka, T.; Wakasa, T.; Wakui, T.

    2007-01-01

    It is possible to use nucleon-nucleus scattering as a probe of the spin structure of the nuclei since target related observables are extremely sensitive to spin dependent parts of the target wave function. In addition, one can gain information about the nucleon-nucleus reaction mechanism, the spin dependent nucleon-nucleon interaction in the nuclear medium, and off-shell behavior of the nucleon-nucleon amplitudes. For 3He(p,3He)p elastic backward scattering, only small amount of data points exist for the differential cross section and no data exist for spin dependent observables. We developed a spin exchange type polarized 3He target and measured the spin correlation parameter Cyy at 200, 300, and 400 MeV.

  3. Nucleon and triton production from nucleon-induced reactions on 7Li

    NASA Astrophysics Data System (ADS)

    Watanabe, Yukinobu; Guo, Hairui; Nagaoka, Kohei; Matsumoto, Takuma; Ogata, Kazuyuki; Yahiro, Masanobu

    2016-06-01

    Nucleon (N) and triton production from nucleon-induced reactions on 7Li at an incident energy of 14 MeV are analyzed by using three-body continuum discretized coupled channels method (CDCC), final state interaction (FSI) model, and sequential decay (SD) model. The CDCC is used to describe nucleon and triton production via breakup continuum channels, 7Li(N,N')7Li*→ t + α. Triton production from p(n) + 7Li → t + 5Li(5He) channel and nucleon production from sequential decay of the ground-state 5Li(5He) are calculated by the FSI model and the SD model, respectively. The calculated double differential cross sections for both nucleon and triton production are in good agreement with experimental ones except at relatively low nucleon emission energies.

  4. Measurement of the neutrino component of an antineutrino beam observed by a nonmagnetized detector

    SciTech Connect

    Aguilar-Arevalo, A. A.; Anderson, C. E.; Fleming, B. T.; Linden, S. K.; Spitz, J.; Brice, S. J.; Brown, B. C.; Ford, R.; Garcia, F. G.; Kobilarcik, T.; Marsh, W.; Moore, C. D.; Polly, C. C.; Russell, A. D.; Stefanski, R. J.; Zeller, G. P.; Bugel, L.; Conrad, J. M.; Karagiorgi, G.; Nguyen, V.

    2011-10-01

    Two methods are employed to measure the neutrino flux of the antineutrino-mode beam observed by the MiniBooNE detector. The first method compares data to simulated event rates in a high-purity {nu}{sub {mu}}-induced charged-current single {pi}{sup +} (CC1{pi}{sup +}) sample while the second exploits the difference between the angular distributions of muons created in {nu}{sub {mu}} and {nu}{sub {mu}} charged-current quasielastic (CCQE) interactions. The results from both analyses indicate the prediction of the neutrino flux component of the predominately antineutrino beam is overestimated--the CC1{pi}{sup +} analysis indicates the predicted {nu}{sub {mu}} flux should be scaled by 0.76{+-}0.11, while the CCQE angular fit yields 0.65{+-}0.23. The energy spectrum of the flux prediction is checked by repeating the analyses in bins of reconstructed neutrino energy, and the results show that the spectral shape is well-modeled. These analyses are a demonstration of techniques for measuring the neutrino contamination of antineutrino beams observed by future nonmagnetized detectors.

  5. A prototype experiment for cooperative monitoring of nuclear reactors with cubic meter scale antineutrino detectors

    NASA Astrophysics Data System (ADS)

    Bernstein, A.; Allen, M.; Bowden, N.; Brennan, J.; Carr, D. J.; Estrada, J.; Hagmann, C.; Lund, J. C.; Madden, N. W.; Winant, C. D.

    2005-09-01

    Our Lawrence Livermore National Laboratory/Sandia National Laboratories collaboration has deployed a cubic-meter-scale antineutrino detector to demonstrate non-intrusive and automatic monitoring of the power levels and plutonium content of a nuclear reactor. Reactor monitoring of this kind is required for all non-nuclear weapons states under the Nuclear Nonproliferation Treaty (NPT), and is implemented by the International Atomic Energy Agency (IAEA). Since the antineutrino count rate and energy spectrum depend on the relative yields of fissioning isotopes in the reactor core, changes in isotopic composition can be observed without ever directly accessing the core. Data from a cubic meter scale antineutrino detector, coupled with the well-understood principles that govern the core's evolution in time, can be used to determine whether the reactor is being operated in an illegitimate way. Our group has deployed a detector at the San Onofre reactor site in California to demonstrate this concept. This paper describes the concept and shows preliminary results from 8 months of operation.

  6. Nucifer: A small electron-antineutrino detector for fundamental and safeguard studies

    SciTech Connect

    Letourneau, A.; Bui, V. M.; Fallot, M.; Giot, L.; Martino, J.; Porta, A.; Varignon, C.; Yermia, F.

    2011-07-01

    The Nucifer detector will be deployed in the next few months at the Osiris research reactor in France. Nucifer is a 1-ton Gd-doped liquid scintillator detector devoted to reactor antineutrino studies. It will be installed 7 m away from the compact core of the Osiris reactor. The design of such small volume detector has been focused on high detection efficiency and good background rejection. Over the last decades, our understanding of the neutrino properties has been improved and allows today the possibility to apply the detection of antineutrinos to automatic and to non intrusively survey nuclear power plant. This has triggered the interest of the International Atomic Energy Agency (IAEA), which is interested by developing new safeguard techniques for next generation reactors. The sensitivity of such technique has to be proved and demonstrated. On the other hand there is still some issues in our understanding of the neutrino properties as the observed deficit in the antineutrino rate at short distances (< 100 m) that can not be explained by oscillations in the 3-flavors neutrino model. If a global systematic error is rejected, such anomaly opens the door to new physic that can be assessed with small detectors placed close to the core. Here we review the Nucifer detector in this context and the tests we are performing. (authors)

  7. Spectral measurement of electron antineutrino oscillation amplitude and frequency at Daya Bay.

    PubMed

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

    2014-02-14

    A measurement of the energy dependence of antineutrino disappearance at the Daya Bay reactor neutrino experiment is reported. Electron antineutrinos (ν¯(e)) from six 2.9  GW(th) reactors were detected with six detectors deployed in two near (effective baselines 512 and 561 m) and one far (1579 m) underground experimental halls. Using 217 days of data, 41 589 (203 809 and 92 912) antineutrino candidates were detected in the far hall (near halls). An improved measurement of the oscillation amplitude sin(2)2θ(13)=0.090(-0.009)(+0.008) and the first direct measurement of the ν¯(e) mass-squared difference |Δm(ee)2|=(2.59(-0.20)(+0.19))×10(-3)  eV2 is obtained using the observed ν¯(e) rates and energy spectra in a three-neutrino framework. This value of |Δm(ee)2| is consistent with |Δm(μμ)2| measured by muon neutrino disappearance, supporting the three-flavor oscillation model. PMID:24580686

  8. An anti-neutrino detector to monitor nuclear reactor's power and fuel composition

    NASA Astrophysics Data System (ADS)

    Battaglieri, M.; DeVita, R.; Firpo, G.; Neuhold, P.; Osipenko, M.; Piombo, D.; Ricco, G.; Ripani, M.; Taiuti, M.

    2010-05-01

    In this contribution, we present the expected performance of a new detector to measure the absolute energy-integrated flux and the energy spectrum of anti-neutrinos emitted by a nuclear power plant. The number of detected anti-neutrino is a direct measure of the power while from the energy spectrum is possible to infer the evolution in time of the core isotopic composition. The proposed method should be sensitive to a sudden change in the core burn-up as caused, for instance, by a fraudulent subtraction of plutonium. The detector, a 130×100×100 cm3 cube with 1 m3 active volume, made by plastic scintillator wrapped in thin Gd foils, is segmented in 50 independent optical channels read, side by side, by a pair of 3 in. photomultipliers. Anti-neutrino interacts with hydrogen contained in the plastic scintillator via the neutron inverse β- decay ( ν¯p→e+n). The high segmentation of the detector allows to reduce the background from other reactions by detecting independent hits for the positron, the two photons emitted in the e+e- annihilation and the neutron.

  9. Two nucleon systems at mπ˜450 MeV from lattice QCD

    NASA Astrophysics Data System (ADS)

    Orginos, Kostas; Parreño, Assumpta; Savage, Martin J.; Beane, Silas R.; Chang, Emmanuel; Detmold, William; Nplqcd Collaboration

    2015-12-01

    Nucleon-nucleon systems are studied with lattice quantum chromodynamics at a pion mass of mπ˜450 MeV in three spatial volumes using nf=2 +1 flavors of light quarks. At the quark masses employed in this work, the deuteron binding energy is calculated to be Bd=14. 4-2.6+3.2 MeV , while the dineutron is bound by Bn n=12. 5-5.0+3.0 MeV . Over the range of energies that are studied, the S-wave scattering phase shifts calculated in the 1S0 and 3S1-3D1 channels are found to be similar to those in nature, and indicate repulsive short-range components of the interactions, consistent with phenomenological nucleon-nucleon interactions. In both channels, the phase shifts are determined at three energies that lie within the radius of convergence of the expansion, allowing for constraints to be placed on the inverse scattering lengths and effective ranges. The extracted phase shifts allow for matching to nuclear effective field theories, from which low-energy counterterms are extracted and issues of convergence are investigated. As part of the analysis, a detailed investigation of the single hadron sector is performed, enabling a precise determination of the violation of the Gell-Mann-Okubo mass relation.

  10. Two nucleon systems at mπ~450MeV from lattice QCD

    DOE PAGESBeta

    Orginos, Kostas; Parreño, Assumpta; Savage, Martin J.; Beane, Silas R.; Chang, Emmanuel; Detmold, William

    2015-12-23

    Nucleon-nucleon systems are studied with lattice quantum chromodynamics at a pion mass ofmore » $$m_\\pi\\sim 450~{\\rm MeV}$$ in three spatial volumes using $n_f=2+1$ flavors of light quarks. At the quark masses employed in this work, the deuteron binding energy is calculated to be $$B_d = 14.4^{+3.2}_{-2.6} ~{\\rm MeV}$$, while the dineutron is bound by $$B_{nn} = 12.5^{+3.0}_{-5.0}~{\\rm MeV}$$. Over the range of energies that are studied, the S-wave scattering phase shifts calculated in the 1S0 and 3S1-3D1 channels are found to be similar to those in nature, and indicate repulsive short-range components of the interactions, consistent with phenomenological nucleon-nucleon interactions. In both channels, the phase shifts are determined at three energies that lie within the radius of convergence of the effective range expansion, allowing for constraints to be placed on the inverse scattering lengths and effective ranges. Thus, the extracted phase shifts allow for matching to nuclear effective field theories, from which low energy counterterms are extracted and issues of convergence are investigated. As part of the analysis, a detailed investigation of the single hadron sector is performed, enabling a precise determination of the violation of the Gell-Mann–Okubo mass relation.« less

  11. Two-Pion Exchange Nucleon-Nucleon Potential: Relativistic Chiral Expansion

    SciTech Connect

    R. Higa; M.R. Robilotta

    2002-08-01

    We present a relativistic procedure for the chiral expansion of the two-pion exchange component of the NN potential, which emphasizes the role of intermediate pi N subamplitudes. The relationship between power counting in pi N and NN processes is discussed and results are expressed directly in terms of observable subthreshold coefficients. Interactions are determined by one and two-loop diagrams, involving pions, nucleons and other degrees of freedom, frozen into empirical subthreshold coefficients. The full evaluation of these diagrams produces amplitudes containing many different loop integrals. Their simplification by means of relations among these integrals leads to a set of intermediate results. Subsequent truncation to order(q{sup 4}) yields the relativistic potential, which depends on four loop integrals, representing bubble, triangle, crossed box and box diagrams. The bubble and triangle integrals are the same as in pi N scattering and we have shown that they also determine the chiral structures of box and crossed box integrals. Relativistic threshold effects were found to begin to contribute at order(q{sup 5}) only and our results should coincide with those of the standard heavy baryon approach. Checking this explicitly, we found differences due to the Goldberger-Treiman discrepancy and terms of order(q{sup 3}), possibly associated with the iteration of the OPEP.

  12. Nucleon exchange in damped nuclear reactions

    SciTech Connect

    Randrup, J.

    1986-04-01

    Starting from the general context of one-body nuclear dynamics, the nucleon-exchange mechanism in damped nuclear reactions is discussed. Some of its characteristic effects on various dinuclear observables are highlighted and a few recent advances are described.

  13. Total Absorption Spectroscopy Study of ⁹²Rb Decay: A Major Contributor to Reactor Antineutrino Spectrum Shape

    DOE PAGESBeta

    Sonzogni, A.; Zakari-Issoufou, A. -A.; Fallot, M.; Porta, A.; Algora, A.; Tain, J. L.; Valencia, E.; Rice, S.; Bui, V. M.; Cormon, S.; et al

    2015-03-09

    The accurate determination of the emitted reactor antineutrino flux is still a major challenge for actual and future neutrino experiments at reactors, especially after the evidence of a disagreement between the measured antineutrino energy spectrum by Double Chooz, Daya Bay, and Reno and calculated antineutrino spectra obtained from the conversion of the unique integral beta spectra measured at the ILL reactor. Using nuclear data to compute reactor antineutrino spectra may help understanding this bias, with the study of the underlying nuclear physics. Summation calculations allow identifying a list of nuclei that contribute importantly to the antineutrino energy spectra emitted aftermore » the fission of ²³⁹,²⁴¹Pu and ²³⁵,²³⁸U, and whose beta decay properties might deserve new measurements. Among these nuclei, ⁹²Rb exhausts by itself about 16% of of the antineutrino energy spectrum emitted by Pressurized Water Reactors in the 5 to 8 MeV range. In this Letter, we report new Total Absorption Spectroscopy (TAS) results for this important contributor. The obtained beta feeding from ⁹²Rb shows beta intensity unobserved before in the 4.5 to 5.5 MeV energy region and gives a ground state to ground state branch of 87.5 % ± 3%. These new data induce a dramatic change in recent summation calculations where a 51% GS to GS branch was considered for ⁹²Rb, increasing the summation antineutrino spectrum in the region nearby the observed bias.The new data still have an important impact on other summation calculations in which more recent data were considered« less

  14. Total Absorption Spectroscopy Study of ⁹²Rb Decay: A Major Contributor to Reactor Antineutrino Spectrum Shape

    SciTech Connect

    Sonzogni, A.; Zakari-Issoufou, A. -A.; Fallot, M.; Porta, A.; Algora, A.; Tain, J. L.; Valencia, E.; Rice, S.; Bui, V. M.; Cormon, S.; Estienne, M.; Agramunt, J.; Aysto, J.; Bowry, M.; Briz Monago, J. A.; Caballero-Folch, R.; Cano-Ott, D.; Cucoanes, A.; Eloma, V.; Estvez, E.; Farrelly, G. F.; Garcia, A.; Gelletly, W.; Gomez-Hornillos, M. B.; Gorlychev, V.; Hakala, J.; Jokinen, A.; Jordan, M. D.; Kankainen, A.; Kondev, F. G.; Martinez, T.; Mendoza, E.; Molina, F.; Moore, I.; Perez, A.; Podolyak, Zs.; Penttil, H.; Regan, P. H.; Shiba, T.; Rissanen, J.; Rubio, B.; Weber, C.

    2015-03-09

    The accurate determination of the emitted reactor antineutrino flux is still a major challenge for actual and future neutrino experiments at reactors, especially after the evidence of a disagreement between the measured antineutrino energy spectrum by Double Chooz, Daya Bay, and Reno and calculated antineutrino spectra obtained from the conversion of the unique integral beta spectra measured at the ILL reactor. Using nuclear data to compute reactor antineutrino spectra may help understanding this bias, with the study of the underlying nuclear physics. Summation calculations allow identifying a list of nuclei that contribute importantly to the antineutrino energy spectra emitted after the fission of ²³⁹,²⁴¹Pu and ²³⁵,²³⁸U, and whose beta decay properties might deserve new measurements. Among these nuclei, ⁹²Rb exhausts by itself about 16% of of the antineutrino energy spectrum emitted by Pressurized Water Reactors in the 5 to 8 MeV range. In this Letter, we report new Total Absorption Spectroscopy (TAS) results for this important contributor. The obtained beta feeding from ⁹²Rb shows beta intensity unobserved before in the 4.5 to 5.5 MeV energy region and gives a ground state to ground state branch of 87.5 % ± 3%. These new data induce a dramatic change in recent summation calculations where a 51% GS to GS branch was considered for ⁹²Rb, increasing the summation antineutrino spectrum in the region nearby the observed bias.The new data still have an important impact on other summation calculations in which more recent data were considered

  15. Nucleon Form Factors from Generalized Parton Distributions

    SciTech Connect

    M. Guidal; Maxim Polyakov; Anatoly Radyushkin; Marc Vanderhaeghen

    2004-10-01

    We discuss the links between Generalized Parton Distributions (GPDs) and elastic nucleon form factors. These links, in the form of sum rules, represent powerful constraints on parametrizations of GPDs. A Regge parametrization for GPDs at small momentum transfer, is extended to the large momentum transfer region and it is found to describe the basic features of proton and neutron electromagnetic form factor data. This parametrization is used to estimate the quark contribution to the nucleon spin.

  16. Nucleon Distribution Amplitudes from Lattice QCD

    SciTech Connect

    Goeckeler, Meinulf; Kaltenbrunner, Thomas; Warkentin, Nikolaus; Horsley, Roger; Zanotti, James M.; Nakamura, Yoshifumi; Pleiter, Dirk; Schierholz, Gerrit; Rakow, Paul E. L.; Schaefer, Andreas; Stueben, Hinnerk

    2008-09-12

    We calculate low moments of the leading-twist and next-to-leading-twist nucleon distribution amplitudes on the lattice using two flavors of clover fermions. The results are presented in the MS scheme at a scale of 2 GeV and can be immediately applied in phenomenological studies. We find that the deviation of the leading-twist nucleon distribution amplitude from its asymptotic form is less pronounced than sometimes claimed in the literature.

  17. Nucleon and Δ electromagnetic form factors

    NASA Astrophysics Data System (ADS)

    Bartoš, Erik; Dubnička, Stanislav; Dubničková, Anna-Zuzana

    2015-11-01

    The unitary and analytic model for nucleons works very well. The model for spin 1 2+ baryons can predict static parameters for Λ, Σ+, Σ0, Σ-, Ξ, Ξ-. We prepared the scheme how to construct the model also for Δ nucleon resonance. It was used to describe transition form factor GM∗ and the experimentally measured ratio RSM with the help of relations for magnetic dipole transition and charge quadrupole form factors.

  18. Lattice results on nucleon/roper properties

    SciTech Connect

    Lin, Huey-Wen

    2009-12-01

    In this proceeding, I review the attempts to calculate the Nucleon resonance (including Roper as first radially excited state of nucleon and other excited states) using lattice quantum chromodynamics (QCD). The latest preliminary results from Hadron Spectrum Collaboration (HSC) with mπ thickapprox 380 MeV are reported. The Sachs electric form factor of the proton and neutron and their transition with the Roper at large Q2 are also updated in this work.

  19. Toward complete pion nucleon amplitudes

    NASA Astrophysics Data System (ADS)

    Mathieu, V.; Danilkin, I. V.; Fernández-Ramírez, C.; Pennington, M. R.; Schott, D.; Szczepaniak, Adam P.; Fox, G.

    2015-10-01

    We compare the low-energy partial-wave analyses of π N scattering with high-energy data via finite-energy sum rules. We construct a new set of amplitudes by matching the imaginary part from the low-energy analysis with the high-energy, Regge parametrization and reconstruct the real parts using dispersion relations.

  20. Toward complete pion nucleon amplitudes

    DOE PAGESBeta

    Mathieu, Vincent; Danilkin, Igor V.; Fernández-Ramírez, Cesar; Pennington, Michael R.; Schott, Diane M.; Szczepaniak, Adam P.; Fox, G.

    2015-10-05

    We compare the low-energy partial wave analyses πN scattering with a high-energy data via finite energy sum rules. We also construct a new set of amplitudes by matching the imaginary part from the low-energy analysis with the high-energy, Regge parametrization and then reconstruct the real parts using dispersion relations.