1,691 research outputs found

    Spin-Correlation Coefficients and Phase-Shift Analysis for p+3^3He Elastic Scattering

    Full text link
    Angular Distributions for the target spin-dependent observables A0y_{0y}, Axx_{xx}, and Ayy_{yy} have been measured using polarized proton beams at several energies between 2 and 6 MeV and a spin-exchange optical pumping polarized 3^3He target. These measurements have been included in a global phase-shift analysis following that of George and Knutson, who reported two best-fit phase-shift solutions to the previous global p+3^3He elastic scattering database below 12 MeV. These new measurements, along with measurements of cross-section and beam-analyzing power made over a similar energy range by Fisher \textit{et al.}, allowed a single, unique solution to be obtained. The new measurements and phase-shifts are compared with theoretical calculations using realistic nucleon-nucleon potential models.Comment: Submitted to Phys. Rev.

    INVESTIGATION INTO THE RATE OF TRIOCTYLAMINE PARTITIONING INTO THE MCU AQUEOUS PHASES

    Get PDF
    The Savannah River National Laboratory (SRNL) has examined the issue of trioctylamine (TOA) losses at the Modular Caustic-Side Solvent Extraction Unit (MCU) solvent. For this study, SRNL used partitioning and radiolysis data from the Oak Ridge National Laboratory (ORNL) as well as actual MCU operational data. From the radiolysis data, SRNL prepared a model on the rate of TOA degradation. From the combined sets of data, SRNL has calculated the largest possible value of TOA (although this value is not credible) in the Strip Effluent (SE) and also calculated two different conservative, more realistic values for TOA in the SE. Even under conservative assumptions, such as all of the TOA losses partitioning solely into the Strip Effluent (SE), the MCU operational data suggests that the maximum realistic TOA concentration in the SE is < 0.6 mg/L. Furthermore, from understanding the chemical differences between the old and new strip solutions, SRNL does not believe that the TOA will deplete from the blended BOBCalixC6 – Next Generation Solvent (NGS-MCU) at a rate higher than previously experienced. Finally, SRNL recommends pursuing analytical development of a method for TOA with a superior precision compared to the current method. However, as the TOA in the blended solvent will continuously decline during MCU operations, further improvements in the development of the understanding of TOA losses may not be cost effective

    Supersymmetric QCD flavor changing top quark decay

    Get PDF
    We present a detailed and complete calculation of the gluino and scalar quarks contribution to the flavour-changing top quark decay into a charm quark and a photon, gluon, or a Z boson within the minimal supersymmetric standard model including flavour changing gluino-quarks-scalar quarks couplings in the right-handed sector. We compare the results with the ones presented in an earlier paper where we considered flavour changing couplings only in the left-handed sector. We show that these new couplings have important consequences leading to a large enhancement when the mixing of the scalar partners of the left- and right-handed top quark is included. Furthermore CP violation in the flavour changing top quark decay will occur when a SUSY phase is taken into account.Comment: 14 pages, latex, 3 figure

    Innovative Feed-In Tariff Designs that Limit Policy Costs

    Get PDF
    Feed-in tariffs (FITs) are the most prevalent renewable energy policy used globally to date, and there are many benefits to the certainty offered in the marketplace to reduce development risks and associated financing costs and to grow the renewable energy industry. However, concerns over escalating costs in jurisdictions with FIT policies have led to increased attention on cost control in renewable energy policy design. In recent years, policy mechanisms for containing FIT costs have become more refined, allowing policymakers to exert greater control on policy outcomes and on the resulting costs to ratepayers. As policymakers and regulators in the United States begin to explore the use of FITs, careful consideration must be given to the ways in which policy design can be used to balance the policies' advantages while bounding its costs. This report explores mechanisms that policymakers have implemented to limit FIT policy costs. If designed clearly and transparently, such mechanisms can align policymaker and market expectations for project deployment. Three different policy tools are evaluated: (1) caps, (2) payment level adjustment mechanisms, and (3) auction-based designs. The report employs case studies to explore the strengths and weaknesses of these three cost containment tools. These tools are then evaluated with a set of criteria including predictability for policymakers and the marketplace and the potential for unintended consequences

    Radiative lepton flavor violating decays in the Randall Sundrum background with localized leptons

    Get PDF
    We study the radiative lepton flavor violating l_i -> l_j\gamma decays in the two Higgs doublet model, respecting the Randall Sundrum scenario and estimate the contributions of the KK modes of left (right) handed charged lepton doublets (singlets) on the branching ratios. We observe that the branching ratios are sensitive to the contributions of the charged lepton KK modes.Comment: 23 pages, 10 figures, 2 table

    Flavor changing t -> c l_1^- l_2^+ decay in the general two Higgs doublet model

    Get PDF
    We study the flavor changing t-> c l_1^- l_2^+ decay in the framework of the general two Higgs doublet model, the so called model III. We predict the branching ratio for l_1=\tau, l_2=\mu at the order of magnitude of BR \sim 10^{-8}.Comment: 12 Pages, 5 Figure

    Charge-Transfer Excitations in the Model Superconductor HgBa2_2CuO4+δ_{\bf 4+\delta}

    Full text link
    We report a Cu KK-edge resonant inelastic x-ray scattering (RIXS) study of charge-transfer excitations in the 2-8 eV range in the structurally simple compound HgBa2_2CuO4+δ_{4+\delta} at optimal doping (Tc=96.5T_{\rm c} = 96.5 K). The spectra exhibit a significant dependence on the incident photon energy which we carefully utilize to resolve a multiplet of weakly-dispersive (<0.5 < 0.5 eV) electron-hole excitations, including a mode at 2 eV. The observation of this 2 eV excitation suggests the existence of a charge-transfer pseudogap deep in the superconducting phase. Quite generally, our data demonstrate the importance of exploring the incident photon energy dependence of the RIXS cross section.Comment: 5 pages, 3 figure

    Unraveling the Nature of Charge Excitations in La2_2CuO4_4 with Momentum-Resolved Cu KK-edge Resonant Inelastic X-ray Scattering

    Full text link
    Results of model calculations using exact diagonalization reveal the orbital character of states associated with different Raman loss peaks in Cu KK-edge resonant inelastic X-ray scattering (RIXS) from La2_{2}CuO4_{4}. The model includes electronic orbitals necessary to highlight non-local Zhang-Rice singlet, charge transfer and dd-dd excitations, as well as states with apical oxygen 2pzp_z character. The dispersion of these excitations is discussed with prospects for resonant final state wave-function mapping. A good agreement with experiments emphasizes the substantial multi-orbital character of RIXS profiles in the energy transfer range 1-6 eV.Comment: Original: 4.5 pages. Replaced: 4 pages and 4 figures with updated content and reference

    The 63^{63}Ni(n,Îł\gamma) cross section measured with DANCE

    Get PDF
    The neutron capture cross section of the s-process branch nucleus 63^{63}Ni affects the abundances of other nuclei in its region, especially 63^{63}Cu and 64^{64}Zn. In order to determine the energy dependent neutron capture cross section in the astrophysical energy region, an experiment at the Los Alamos National Laboratory has been performed using the calorimetric 4Ď€\pi BaF2_2 array DANCE. The (n,Îł\gamma) cross section of 63^{63}Ni has been determined relative to the well known 197^{197}Au standard with uncertainties below 15%. Various 63^{63}Ni resonances have been identified based on the Q-value. Furthermore, the s-process sensitivity of the new values was analyzed with the new network calculation tool NETZ.Comment: 11 pages, 13 page
    • …
    corecore