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Sample records for pi-pi stacking interaction

  1. Homeotropic alignment of the lyotropic chromonic liquid crystal Sunset Yellow FCF using pi-pi stacking chemical interactions

    NASA Astrophysics Data System (ADS)

    Jeong, Joonwoo; Han, Ganghee; Johnson, A. T. Charlie; Lubensky, Tom C.; Collings, Peter J.; Yodh, A. G.

    2013-03-01

    We report on the homeotropic alignment of the lyotropic chromonic liquid crystal, Sunset Yellow FCF (SSY), using pi-pi stacking interactions between the SSY molecules and (1) thin parylene films or (2) a graphene monolayer. The nematic and columnar phases of SSY molecules arise via self-assembly in water into stacks through non-covalent attractions between the SSY molecules. Interestingly, we find that the same non-covalent interactions between SSY molecules and a parylene or graphene alignment layer lead to homeotropic anchoring of these stacks. The nematic phase of SSY is introduced between two glass substrates coated with parylene films or graphene monolayers, and homeotropic alignment of SSY is confirmed by polarized optical microscopy and conoscopy. Additionally, we observe and can explain the stripe domains that occur during cooling of the sample in this cell, and we consider possible novel applications for homeotropically aligned chromonic liquid crystals. We gratefully acknowledge financial support from the National Science Foundation through NSF DMR-1205463 and UPENN MRSEC DMR-1120901

  2. A series of Cd(II) complexes with {pi}-{pi} stacking and hydrogen bonding interactions: Structural diversities by varying the ligands

    SciTech Connect

    Wang Xiuli; Zhang Jinxia; Liu Guocheng; Lin Hongyan

    2011-02-15

    Seven new Cd(II) complexes consisting of different phenanthroline derivatives and organic acid ligands, formulated as [Cd(PIP){sub 2}(dnba){sub 2}] (1), [Cd(PIP)(ox)].H{sub 2}O (2), [Cd(PIP)(1,4-bdc)(H{sub 2}O)].4H{sub 2}O (3), [Cd(3-PIP){sub 2}(H{sub 2}O){sub 2}].4H{sub 2}O (4), [Cd{sub 2}(3-PIP){sub 4}(4,4'-bpdc)(H{sub 2}O){sub 2}].5H{sub 2}O (5), [Cd(3-PIP)(nip)(H{sub 2}O)].H{sub 2}O (6), [Cd{sub 2}(TIP){sub 4}(4,4'-bpdc)(H{sub 2}O){sub 2}].3H{sub 2}O (7) (PIP=2-phenylimidazo[4,5-f]1,10-phenanthroline, 3-PIP=2-(3-pyridyl)imidazo[4,5-f]1,10-phenanthroline, TIP=2-(2-thienyl)imidazo[4,5-f]1,10-phenanthroline, Hdnba=3,5-dinitrobenzoic acid, H{sub 2}ox=oxalic acid, 1,4-H{sub 2}bdc=benzene-1,4-dicarboxylic acid, 4,4'-H{sub 2}bpdc=biphenyl-4,4'-dicarboxylic acid, H{sub 2}nip=5-nitroisophthalic acid) have been synthesized under hydrothermal conditions. Complexes 1 and 4 possess mononuclear structures; complexes 5 and 7 are isostructural and have dinuclear structures; complexes 2 and 3 feature 1D chain structures; complex 6 contains 1D double chain, which are further extended to a 3D supramolecular structure by {pi}-{pi} stacking and hydrogen bonding interactions. The N-donor ligands with extended {pi}-system and organic acid ligands play a crucial role in the formation of the final supramolecular frameworks. Moreover, thermal properties and fluorescence of 1-7 are also investigated. -- Graphical abstract: Seven new supramolecular architectures have been successfully isolated under hydrothermal conditions by reactions of different phen derivatives and Cd(II) salts together with organic carboxylate anions auxiliary ligands. Display Omitted Research highlights: {yields} Complexes 1-7 are 0D or 1D polymeric structure, the {pi}-{pi} stacking and H-bonding interactions extend the complexes into 3D supramolecular network. To our knowledge, systematic study on {pi}-{pi} stacking and H-bonding interactions in cadmium(II) complexes are still limited. {yields} The structural

  3. Intracomplex {pi}-{pi} stacking interaction between adjacent phenanthroline molecules in complexes with rare-earth nitrates: Crystal and molecular structures of bis(1,10-Phenanthroline)trinitratoytterbium and bis(1,10-Phenanthroline)trinitratolanthanum

    SciTech Connect

    Sadikov, G. G. Antsyshkina, A. S.; Rodnikova, M. N.; Solonina, I. A.

    2009-01-15

    Crystals of the compounds Yb(NO{sub 3}){sub 3}(Phen){sub 2} and La(NO{sub 3}){sub 3}(Phen){sub 2} (Phen = 1,10-phenanthroline) are investigated using X-ray diffraction. It is established that there exist two different crystalline modifications: the main modification (phase 1) is characteristic of all members of the isostructural series, and the second modification (phase 2) is observed only for the Eu, Er, and Yb elements. It is assumed that the stability and universality of main phase 1 are associated with the occurrence of the nonbonded {pi}-{pi} stacking interactions between the adjacent phenanthroline ligands in the complexes. The indication of the interactions is a distortion of the planar shape of the Phen molecule (the folding of the metallocycle along the N-N line with a folding angle of 11{sup o}-13{sup o} and its 'boomerang' distortion). The assumption regarding the {pi}-{pi} stacking interaction is very consistent with the shape of the ellipsoids of atomic thermal vibrations, as well as with the data obtained from thermography and IR spectroscopy. An analysis of the structures of a number of rare-earth compounds has demonstrated that the intracomplex {pi}-{pi} stacking interactions directly contribute to the formation of supramolecular associates in the crystals, such as molecular dimers, supramolecules, chain and layered ensembles, and framework systems.

  4. {pi}-{pi} Interactions and magnetic properties in a series of hybrid inorganic-organic crystals

    SciTech Connect

    Gonzalez, M.; Lemus-Santana, A.A.; Rodriguez-Hernandez, J.; Knobel, M.; Reguera, E.

    2013-01-15

    The series of hybrid inorganic-organic solids T(Im){sub 2}[Ni(CN){sub 4}] with T=Fe, Co, Ni and Im=imidazole were prepared by soft chemical routes from aqueous solutions of the involved building units: imidazole, T{sup 2+} metal and the [Ni(CN){sub 4}]{sup 2-} anionic block. The obtained samples were characterized from infrared and UV-vis spectroscopies, and thermogravimetric, X-ray diffraction and magnetic measurements. Anhydrous solids which crystallize with a monoclinic unit cell, in the I2/a space group with four formula units per cell (Z=4) were obtained. Their crystal structure was solved ab initio from the recorded X-ray powder patterns and then refined by the Rietveld method. The metal T is found with octahedral coordination to four N ends of CN groups and two imidazole molecules while the inner Ni atom preserves its planar coordination. The system of layers remains stacked in an ordered 3D structure through dipole-dipole and {pi}-{pi} interactions between imidazole rings from neighboring layers. In this way, a pillared structure is achieved without requiring the coordination of both nitrogen atoms from imidazole ring. The recorded magnetic data indicate the occurrence of a predominant ferromagnetic interaction at low temperature for Co and Ni but not for Fe. Such magnetic ordering is more favorable for Ni with transition temperature of 14.67 K, which was ascribed to the relatively high polarizing power for this metal. Within the considered T metals, to nickel the highest electron-withdrawing ability corresponds and this leads to an increase for the metal-ligand electron clouds overlapping and to a stronger {pi}-{pi} attractive interaction, two factors that result into a higher magnetic ordering temperature. - Graphical Abstract: Magnetic ordering through the {pi}-{pi} interaction between the imidazole rings. Highlights: Black-Right-Pointing-Pointer Hybrid inorganic-organic solids. Black-Right-Pointing-Pointer Hybrid inorganic-organic molecular based

  5. Photoluminescence and conductivity of self-assembled pi-pi stacks of perylene bisimide dyes.

    PubMed

    Chen, Zhijian; Stepanenko, Vladimir; Dehm, Volker; Prins, Paulette; Siebbeles, Laurens D A; Seibt, Joachim; Marquetand, Philipp; Engel, Volker; Würthner, Frank

    2007-01-01

    The self-assembly of a new, highly fluorescent perylene bisimide dye 2 into pi stacks, both in solution and condensed phase, has been studied in detail by NMR spectroscopy, vapor pressure osmometry (VPO), UV/Vis and fluorescence spectroscopy, differential scanning calorimetry (DSC), optical polarizing microscopy (OPM) and X-ray diffraction. The NMR and VPO measurements revealed the formation of extended pi-pi stacks of the dye molecules in solution. The aggregate size determined from VPO and DOSY NMR measurements agree well with that obtained from the concentration and temperature-dependent UV/Vis spectral data by employing the isodesmic model (equal K model). In the condensed state, dye 2 possesses a hexagonal columnar liquid crystalline (LC) phase as confirmed by X-ray diffraction analysis. The columnar stacking of this dye has been further explored by atomic force microscopy (AFM). Well-resolved columnar nanostructures of the compound are observed on graphite surface. A color-tunable luminescence from green to red has been observed upon aggregation which is accompanied by an increase of the fluorescence lifetime and depolarization. The observed absorption properties can be explained in terms of molecular exciton theory. The charge transport properties of dye 2 have been investigated by pulse radiolysis-time resolved microwave conductivity measurements and a 1D charge carrier mobility up to 0.42 cm(2) V(-1) s(-1) is obtained. Considering the promising self-assembly, semiconducting, and luminescence properties of this dye, it might serve as a useful functional material for nano(opto)electronics. PMID:17143925

  6. Equation of state of an interacting pion gas with realistic {pi}-{pi} interactions

    SciTech Connect

    Rapp, R.; Wambach, J.

    1996-06-01

    Within the finite-temperature Green{close_quote}s-function formalism we study the equation of state of a hot interacting pion gas at zero chemical potential. Employing realistic {pi}{pi} meson-exchange interactions, we self-consistently calculate the in-medium single-pion self-energy and the {pi}{pi} scattering amplitude in the quasiparticle approximation. These quantities are then used to evaluate the thermodynamic potential {Omega}{sub {pi}}({ital T}) from which the state variables of pressure, entropy, and energy density can be derived. In contrast to earlier calculations based on the low-energy Weinberg Lagrangian we find an overall increase as compared to the free-gas results. We also consider the possibility of a dropping {rho}-meson mass as suggested by the {open_quote}{open_quote}Brown-Rho scaling{close_quote}{close_quote} law. {copyright} {ital 1996 The American Physical Society.}

  7. Self-assembled nanolayers of conjugated silane with pi-pi interlocking.

    PubMed

    Jiang, Jinyue; Lima, Ocelio V; Pei, Yong; Jiang, Zhang; Chen, Ziguang; Yu, Chichao; Wang, Jin; Zeng, Xiao Cheng; Forsythe, Eric; Tan, Li

    2010-07-27

    The packing of electronic molecules into planar structures and an ensured pi-pi interaction within the plane are preferred for efficient organic transistors. Thin films of organic electronics are exemplar, but the widely adopted molecular design and associated fabrication lead to limited ordering in multistack construction motifs. Here we demonstrate self-assembled nanolayers of organic molecules having potential electronic utility using an amphiphilic silane as a building block. Unlike a cross-linked (tetrahedral) configuration found in conventional siloxane networks, a linear polymer chain is produced following silane polycondensation. As a result, hydrophobic branches plus a noncovalent pi-pi interlocking between the molecules promote planar packing and continuous stacking along the surface normal. In contrast to conventional pi-pi stacking or hydrogen bonding pathways in a fibrous construct, multistacked nanolayers with coexisting pi-pi and herringbone interlocking can provide unmatched properties and processing convenience in molecular electronics. PMID:20518569

  8. DABCO-metallopophyrin binding: Ternary complexes, host-guest chemistry, and the measurement of. pi. -. pi. interactions

    SciTech Connect

    Hunter, C.A.; Meah, M.N.; Sanders, J.K.M. )

    1990-07-18

    Transient ternary complexes of the general form metalloporphyrin-DABCO-metalloporphyrin are described and characterized by NMR spectroscopy: the protons of DABCO (1,4-diazobicyclo(2.2.2)octane) molecules sandwiched between two diamagnetic metalloporphyrins resonate around {minus}5 ppm. The same structural motif is shown to occur when DABCO binds within the cavity of cofacial metalloporphyrin dimers. The kinetics and thermodynamics of intracavity binding were measured by electronic and NMR spectroscopy and lead to an estimate of 48 {plus minus} 10 kJ mol{sup {minus}1} (11.5 {plus minus} 2.4 kcal mol{sup {minus}1}) for the enthalpy of the {pi}-{pi} interaction between two zinc porphyrin moieties. The mechanism of ligand exchange and isomer interconversion for one of the porphyrin dimers has also been elucidated.

  9. Noncovalent Pi-Pi Stacking at the Carbon-Electrolyte Interface: Controlling the Voltage Window of Electrochemical Supercapacitors.

    PubMed

    Li, Mengya; Westover, Andrew S; Carter, Rachel; Oakes, Landon; Muralidharan, Nitin; Boire, Timothy C; Sung, Hak-Joon; Pint, Cary L

    2016-08-01

    A key parameter in the operation of an electrochemical double-layer capacitor is the voltage window, which dictates the device energy density and power density. Here we demonstrate experimental evidence that π-π stacking at a carbon-ionic liquid interface can modify the operation voltage of a supercapacitor device by up to 30%, and this can be recovered by steric hindrance at the electrode-electrolyte interface introduced by poly(ethylene oxide) polymer electrolyte additives. This observation is supported by Raman spectroscopy, electrochemical impedance spectroscopy, and differential scanning calorimetry that each independently elucidates the signature of π-π stacking between imidazole groups in the ionic liquid and the carbon surface and the role this plays to lower the energy barrier for charge transfer at the electrode-electrolyte interface. This effect is further observed universally across two separate ionic liquid electrolyte systems and is validated by control experiments showing an invariant electrochemical window in the absence of a carbon-ionic liquid electrode-electrolyte interface. As interfacial or noncovalent interactions are usually neglected in the mechanistic picture of double-layer capacitors, this work highlights the importance of understanding chemical properties at supercapacitor interfaces to engineer voltage and energy capability. PMID:27380273

  10. Observation of eta_c(1S) and eta_c(2S) decays to K K-pi pi-pi0 in two-photon interactions

    SciTech Connect

    Sanchez, P.del Amo

    2011-05-20

    We study the processes {gamma}{gamma} {yields} K{sub S}{sup 0}K{sup {+-}}{pi}{sup {-+}} and {gamma}{gamma} {yields} K{sup +}K{sup -}{pi}{sup +}{pi}{sup -}{pi}{sup 0} using a data sample of 519.2 fb{sup -1} recorded by the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at center-of-mass energies near the {Upsilon}(nS) (n = 2, 3, 4) resonances. We observe the {eta}{sub c}(1S), {chi}{sub c0}(1P), {chi}{sub c2}(1P), and {eta}{sub c}(2S) resonances produced in two-photon interactions and decaying to K{sup +}K{sup -}{pi}{sup +}{pi}{sup -}{pi}{sup 0}, with significances of 18.1, 5.7, 5.2, and 5.3 standard deviations (including systematic errors), respectively. We measure the {eta}{sub c}(2S) mass and width in K{sub S}{sup 0}K{sup {+-}}{pi}{sup {-+}} decays, m({eta}{sub c}(2S)) = 3638.5 {+-} 1.5 {+-} 0.8 MeV/c{sup 2} and {Lambda}({eta}{sub c}(2S)) = 13.4 {+-} 4.6 {+-} 3.2 MeV, where the first uncertainty is statistical and the second is systematic. We search for the Z(3930) resonance and find no significant signal. We also provide the two-photon width times branching fraction values for the observed resonances.

  11. Intramolecular "Aryl-metal chelate ring" pi,pi-interactions as structural evidence for metalloaromaticity in (aromatic alpha,alpha'-diimine)-copper(II) chelates: molecular and crystal structure of aqua(1,10-phenanthroline)(2-benzylmalonato)copper(II) three-hydrate.

    PubMed

    Castiñeiras, A; Sicilia-Zafra, A G; González-Pérez, J M; Choquesillo-Lazarte, D; Niclós-Gutiérrez, J

    2002-12-30

    By reaction of Cu(2)CO(3)(OH)(2), 2-benzylmalonic acid (H(2)Bzmal), and 1,10-phenanthroline (phen), [Cu(Bzmal)(phen)(H(2)O)] x 3H(2)O (compound 1) has been obtained and characterized by thermal, spectral, magnetic, and X-ray diffraction methods. The molecular structure of 1 is remarkably similar to that of [Cu(Bzmal)(bipy)(H(2)O)] x 2H(2)O (compound 2, bipy = 2,2'-bipyridine). In both complexes, the aryl(Bzmal) ring produces an unexpected pi,pi-stacking interaction with the Cu(II)-(aromatic alpha,alpha'-diimine) chelate ring, at an average distance d(pi)(-)(pi) of 3.40 A, involving roughly parallel and smoothly slipped rings. This insight is discussed as new structural evidence for metalloaromaticity of Cu(II)-(aromatic alpha,alpha'-diimine) chelate rings. Interestingly, 1 recognizes itself by a weak intermolecular pi,pi-stacking interaction between aryl(Bzmal) ligands to give pairs of complex molecules. In contrast, there is an intermolecular pyridyl-pyridyl pi,pi-stacking interaction also forming pairs of complex molecules in 2. PMID:12495333

  12. Measurement of ratio R = (BR(D{sup 0}{yields}K{pi}{pi}{pi})/BR(D{sup 0}{yields}K{pi})) in {pi}{sup -}-Nucleus interactions at 500 GeV/c

    SciTech Connect

    Solano Salinas, C. J.; Paucarchuco, C.; Fernandez, A.; Sheaff, M.

    2007-10-26

    We report a very preliminary result on the measurement of the ratio of branching ratios, for two decays D{sup 0} meson, R = (BR(D{sup 0}{yields}K{pi}{pi}{pi})/BR(D{sup 0}{yields}K{pi})), using data from the E791 experiment. We find R = 1.96{+-}0.0286 (stat){+-}0.06 (sys). This is in agreement with and of similar precision to the current PDG average value 1.97{+-}0.09.

  13. Study of the D{sup 0{yields}{pi}+{pi}-{pi}0} decay at BABAR

    SciTech Connect

    Gaspero, Mario

    2010-08-05

    The Dalitz-plot of the decay D{sup 0{yields}{pi}+{pi}-{pi}0} measured by the BABAR collaboration shows the structure of a final state having quantum numbers I{sup G}J{sup PC} = 0{sup -}0{sup --}. An isospin analysis of this Dalitz-plot finds that the fraction of the I = 0 contribution is about 96%. This high I = 0 contribution is unexpected because the weak interaction violates the isospin.

  14. Hydrogen bonding and pi-pi interactions in a laminar structure: benzene-1,3-dicarboxylic acid-4-methylpyridine (1/2).

    PubMed

    Jin, Zhi-Min; Feng, Hai; Tu, Bing; Li, Mei-Chao; Hu, Mao-Lin

    2005-10-01

    The title complex, C8H6O4.2C6H7N, consists of two crystallographically independent 1:2 clusters of benzene-1,3-dicarboxylic acid and 4-methylpyridine. Each cluster, the components of which are linked by O-H...N hydrogen bonds, is almost planar by alignment of C-H...O hydrogen bonds. Herring-bone ribbons of clusters are formed by other C-H...O hydrogen bonds, and these ribbons are further packed to form a laminar structure by pi-pi interactions. PMID:16210766

  15. Diffractive Pion Dissociation into {pi}{sup -{pi}+{pi}-{pi}+{pi}-} at COMPASS

    SciTech Connect

    Neubert, S.

    2010-08-05

    At the COMPASS experiment a sample of {approx}380000 exclusive events of diffractive pion dissociation on a lead target into a {pi}{sup -{pi}+{pi}-{pi}+{pi}-} final state has been recorded in 2004. The 5{pi} invariant mass spectrum shows a momentum transfer dependent structure peaking around 1.8 GeV/c{sup 2}. In the (4{pi}){sup 0} subsystem there is a clear signal for the f{sub 1}(1285) resonance decaying into 4 pions. In this note we describe the data sample and explore the physics potential of this final state.

  16. New type of dual solid-state thermochromism: modulation of intramolecular charge transfer by intermolecular pi-pi interactions, kinetic trapping of the aci-nitro group, and reversible molecular locking.

    PubMed

    Naumov, Pance; Lee, Sang Cheol; Ishizawa, Nobuo; Jeong, Young Gyu; Chung, Ihn Hee; Fukuzumi, Shunichi

    2009-10-22

    When heated above room temperature, some crystalline polymorphs of the 1,3-bis(hydroxyalkylamino)-4,6-dinitrobenzenes (BDBn, n = 2-5), bis(hydroxyalkyl) analogues of the intramolecular charge-transfer molecule 1,3-diamino-4,6-dinitrobenzene, exhibit "dual" thermochromism: gradual color change from yellow to orange at lower temperatures, and sharp color change from orange to red at higher temperatures. These two thermochromic changes are related to different solid-state processes. When allowed to cool to room temperature, the yellow color of the thermochromic molecules with different alkyl length (n) is recovered with unexpectedly different kinetics, the order of the respective rate constants ranging from 10(-7)-10(-6) s(-1) for BDB2 to about 0.1 s(-1) in the case of BDB3. The thermochromic mechanism and the reasons behind the different kinetics were clarified on the basis of detailed crystallographic characterization, kinetic thermoanalysis, and spectroscopic study of eight crystalline forms (seven polymorphs and one solvate). It was found that the polymorphism is due to the possibility of "locking" and "unlocking" of the alkyl arms by formation of a strong intramolecular hydrogen bond between the hydroxyl groups at their hydroxyl termini. The locking of BDB2, with shortest alkyl arms, is reversible and it can be controlled thermally; either of the two conformations can be obtained in the solid state by proper thermal treatment. By use of high temperature in situ single crystal X-ray diffraction analysis of BDB3, direct evidence was obtained that the gradual thermochromic change is related to increased distance and weakened pi-pi interactions between the stacked benzene rings: the lattice expands preferably in the stacking direction, causing enhanced oscillator strength and red shift of the absorption edge of the intramolecular charge transfer transition. The second, sharp thermochromic change had been assigned previously to solid-solid phase transition triggered

  17. Nitrogen-Doping Enables Covalent-Like pi-pi Bonding between Graphenes

    SciTech Connect

    Tian, Yong-Hui; Huang, Jingsong; Sumpter, Bobby G; Kertesz, Prof. Miklos

    2015-01-01

    The neighboring layers in bi-layer (and few-layer) graphenes of both AA and AB stacking motifs are known to be separated at a distance corresponding to van der Waals (vdW) interactions. In this Letter, we present for the first time a new aspect of graphene chemistry in terms of a special chemical bonding between the giant graphene molecules . Through rigorous theoretical calculations, we demonstrate that the N-doped graphenes (NGPs) with various doping levels can form an unusual two-dimensional (2D) pi pi bonding in bi-layer NGPs bringing the neighboring NGPs to significantly reduced interlayer separations. The interlayer binding energies can be enhanced by up to 50% compared to the pristine graphene bi-layers that are characterized by only vdW interactions. Such an unusual chemical bonding arises from the pi pi overlap across the vdW gap while the individual layers maintain their in-plane pi-conjugation and are accordingly planar. The existence of the resulting interlayer covalent-like bonding is corroborated by electronic structure calculations and crystal orbital overlap population (COOP) analyses. In NGP-based graphite with the optimal doping level, the NGP layers are uniformly stacked and the 3D bulk exhibits metallic characteristics both in the in-plane and along the stacking directions.

  18. Dispersion relations with crossing symmetry for {pi}{pi} D- and F-wave amplitudes

    SciTech Connect

    Kaminski, R.

    2011-04-01

    A set of once subtracted dispersion relations with imposed crossing symmetry condition for the {pi}{pi} D- and F-wave amplitudes is derived and analyzed. An example of numerical calculations in the effective two-pion mass range from the threshold to 1.1 GeV is presented. It is shown that these new dispersion relations impose quite strong constraints on the analyzed {pi}{pi} interactions and are very useful tools to test the {pi}{pi} amplitudes. One of the goals of this work is to provide a complete set of equations required for easy use. Full analytical expressions are presented. Along with the well-known dispersion relations successful in testing the {pi}{pi} S- and P-wave amplitudes, those presented here for the D and F waves give a complete set of tools for analyses of the {pi}{pi} interactions.

  19. Dynamical coupled-channels study of {pi}N {right arrow} {pi pi}N reactions.

    SciTech Connect

    Kamano, H.; Julia-Diaz, B.; Lee, T.-S. H.; Matsuyama, A.; Sato, T.; Physics; Jefferson Lab.; Univ. of Barcelona; Shizuoka Univ.; Osaka Univ.

    2009-02-24

    As a step toward performing a complete coupled-channels analysis of the world data of {pi}N,{gamma}*N {yields} {pi}N,{eta}N,{pi}{pi}N reactions, the {pi}N {yields} {pi}{pi}N reactions are investigated starting with the dynamical coupled-channels model developed in Phys. Rev. C 76, 065201 (2007). The channels included are {pi}N,{eta}N, and {pi}{pi}N which has {pi}{Delta},{rho}N, and {sigma}N resonant components. The nonresonant amplitudes are generated from solving a set of coupled-channels equations with the meson-baryon potentials defined by effective Lagrangians. The resonant amplitudes are generated from 16 bare excited nucleon (N*) states that are dressed by the nonresonant interactions as constrained by the unitarity condition. The data of total cross sections and {pi}N and {pi}{pi} invariant mass distributions of {pi} + p {yields} {pi} + {pi} + n, {pi} + {pi}0p and {pi} - p {yields} {pi} + {pi} - n, {pi} - {pi}0p,{pi}0{pi}0n reactions from threshold to the invariant mass W = 2 GeV can be described to a very large extent. We show the importance of the coupled-channels effects and the strong interference among the contributions from the {pi}{Delta},{sigma}N, and {rho}N channels. The large interference between the resonant and nonresonant amplitudes is also demonstrated. Possible future developments are discussed.

  20. Dynamical coupled-channels study of pi N --> pi pi N reactions

    SciTech Connect

    Kamano, Hiroyuki; Julia Diaz, Bruno; Lee, Tsung-Shung; Matsuyama, Akihiko; Sato, Toru

    2009-01-01

    As a step toward performing a complete coupled-channels analysis of the world data of pi N, gamma^* N --> pi N, eta N, pi pi N reactions, the pi N --> pi pi N reactions are investigated starting with the dynamical coupled-channels model developed in Phys. Rev. C76, 065201 (2007). The channels included are pi N, eta N, and pi pi N which has pi Delta, rho N, and sigma N resonant components. The non-resonant amplitudes are generated from solving a set of coupled-channels equations with the meson-baryon potentials defined by effective Lagrangians. The resonant amplitudes are generated from 16 bare excited nucleon (N^*) states which are dressed by the non-resonant interactions as constrained by the unitarity condition. The available total cross section data of pi^+ p --> pi^+ pi^+ n, pi^+ pi^0 and pi^- p --> pi^+ pi^- n, pi^- pi^0 n, pi^0 pi^0 n can be reproduced to a very large extent both in magnitudes and energy-dependence. Possible improvements of the model are investigated, in p

  1. Measurement of CP violation parameters with a Dalitz plot analysis of B{+/-}-->D{pi{+}pi{-}pi{0}}K{+/-}.

    PubMed

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

    2007-12-21

    We report the results of a CP violation analysis of the decay B{+/-}-->D{pi{+}pi{-}pi;{0}}K{+/-}, where D{pi{+}pi{-}pi{0}} indicates a neutral D meson detected in the final state pi{+}pi{-}pi{0}, excluding K{S}{0}pi{0}. The analysis makes use of 324 x 10{6}e{+}e{-}-->BB[over ] events recorded by the BABAR experiment at the PEP-II e;{+}e;{-} storage ring. Analyzing the pi;{+}pi;{-}pi;{0} Dalitz plot distribution and the B{+/-}-->D{pi{+}pi{-}pi{0}}K{+/-} branching fraction and decay rate asymmetry, we find the following one-standard-deviation constraints on the amplitude ratio and on the weak and strong phases: 0.06pi{+}pi{-}pi{0} decay amplitude. PMID:18233513

  2. Charmless decays B{yields}{pi}{pi},{pi}K and KK in broken SU(3) symmetry

    SciTech Connect

    Wu Yueliang; Zhou Yufeng

    2005-08-01

    Charmless B decay modes B{yields}{pi}{pi},{pi}K and KK are systematically investigated with and without flavor SU(3) symmetry. Independent analyses on {pi}{pi} and {pi}K modes both favor a large ratio between color-suppressed tree (C) and tree (T) diagram, which suggests that they are more likely to originate from long distance effects. The sizes of QCD penguin diagrams extracted individually from {pi}{pi}, {pi}K and KK modes are found to follow a pattern of SU(3) breaking in agreement with the naive factorization estimates. Global fits to these modes are done under various scenarios of SU(3) relations. The results show good determinations of weak phase {gamma} in consistency with the standard model (SM), but a large electroweak penguin (P{sub EW}) relative to T+C with a large relative strong phase is favored, which requires a big enhancement of color-suppressed electroweak penguin (P{sub EW}{sup C}) compatible in size but destructively interfering with P{sub EW} within the SM, or implies new physics. The possibilities of sizable contributions from nonfactorizable diagrams such as W exchange (E), annihilation (A), and penguin-annihilation diagrams (P{sub A}) are investigated. The implications to the branching ratios and CP violations in KK modes are discussed.

  3. Search for the photoexcitation of exotic mesons in the pi+pi+pi- system.

    PubMed

    Nozar, M; Salgado, C; Weygand, D P; Guo, L; Adams, G; Li, Ji; Eugenio, P; Amaryan, M J; Anghinolfi, M; Asryan, G; Avakian, H; Bagdasaryan, H; Baillie, N; Ball, J P; Baltzell, N A; Barrow, S; Battaglieri, M; Bedlinskiy, I; Bektasoglu, M; Bellis, M; Benmouna, N; Berman, B L; Biselli, A S; Blaszczyk, L; Bonner, B E; Bouchigny, S; Boiarinov, S; Bradford, R; Branford, D; Briscoe, W J; Brooks, W K; Bültmann, S; Burkert, V D; Butuceanu, C; Calarco, J R; Careccia, S L; Carman, D S; Carnahan, B; Casey, L; Cazes, A; Chen, S; Cheng, L; Cole, P L; Collins, P; Coltharp, P; Cords, D; Corvisiero, P; Crabb, D; Crannell, H; Crede, V; Cummings, J P; Dale, D; Dashyan, N; De Masi, R; De Vita, R; De Sanctis, E; Degtyarenko, P V; Denizli, H; Dennis, L; Deur, A; Dharmawardane, K V; Dhuga, K S; Dickson, R; Djalali, C; Dodge, G E; Doughty, D; Dugger, M; Dytman, S; Dzyubak, O P; Egiyan, H; Egiyan, K S; El Fassi, L; Elouadrhiri, L; Fatemi, R; Fedotov, G; Feuerbach, R J; Forest, T A; Fradi, A; Funsten, H; Garçon, M; Gavalian, G; Gevorgyan, N; Gilfoyle, G P; Giovanetti, K L; Girod, F X; Goetz, J T; Gothe, R W; Griffioen, K A; Guidal, M; Guillo, M; Guler, N; Gyurjyan, V; Hadjidakis, C; Hafidi, K; Hakobyan, H; Hanretty, C; Hardie, J; Hassall, N; Heddle, D; Hersman, F W; Hicks, K; Hleiqawi, I; Holtrop, M; Hyde-Wright, C E; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Isupov, E L; Ito, M M; Jenkins, D; Jo, H S; Johnstone, J R; Joo, K; Juengst, H G; Kalantarians, N; Kellie, J D; Khandaker, M; Kim, W; Klein, A; Klein, F J; Kossov, M; Krahn, Z; Kramer, L H; Kubarovsky, V; Kuhn, J; Kuhn, S E; Kuleshov, S V; Kuznetsov, V; Lachniet, J; Laget, J M; Langheinrich, J; Lawrence, D; Livingston, K; Lu, H Y; Maccormick, M; Markov, N; Mattione, P; McAleer, S; McKinnon, B; McNabb, J W C; Mecking, B A; Mehrabyan, S; Mestayer, M D; Meyer, C A; Mibe, T; Mikhailov, K; Mirazita, M; Miskimen, R; Mokeev, V; Moreno, B; Moriya, K; Morrow, S A; Moteabbed, M; Mueller, J; Munevar, E; Mutchler, G S; Nadel-Turonski, P; Nasseripour, R; Niccolai, S; Niculescu, G; Niculescu, I; Niczyporuk, B B; Niroula, M R; Niyazov, R A; O'Rielly, G V; Osipenko, M; Ostrovidov, A I; Park, K; Pasyuk, E; Paterson, C; Anefalos Pereira, S; Philips, S A; Pierce, J; Pivnyuk, N; Pocanic, D; Pogorelko, O; Polli, E; Popa, I; 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; Rubin, P D; Sabatié, F; Salamanca, J; Santoro, J P; Sapunenko, V; Schumacher, R A; Serov, V S; Sharabian, Y G; Sharov, D; Shvedunov, N V; Skabelin, A V; Smith, E S; Smith, L C; Sober, D I; Sokhan, D; Stavinsky, A; Stepanyan, S S; Stepanyan, S; Stokes, B E; Stoler, P; Strakovsky, I I; Strauch, S; Taiuti, M; Tedeschi, D J; Thoma, U; Tkabladze, A; Tkachenko, S; Todor, L; Ungaro, M; Vineyard, M F; Vlassov, A V; Watts, D P; Weinstein, L B; Williams, M; Wolin, E; Wood, M H; Yegneswaran, A; Zana, L; Zhang, J; Zhao, B; Zhao, Z W

    2009-03-13

    A search for exotic mesons in the pi;{+}pi;{+}pi;{-} system photoproduced by the charge exchange reaction gammap-->pi;{+}pi;{+}pi;{-}(n) was carried out by the CLAS Collaboration at Jefferson Lab. A tagged-photon beam with energies in the 4.8 to 5.4 GeV range, produced through bremsstrahlung from a 5.744 GeV electron beam, was incident on a liquid-hydrogen target. A partial wave analysis was performed on a sample of 83 000 events, the highest such statistics to date in this reaction at these energies. The main objective of this study was to look for the photoproduction of an exotic J;{PC}=1;{-+} resonant state in the 1 to 2 GeV mass range. Our partial wave analysis shows production of the a_{2}(1320) and the pi_{2}(1670) mesons, but no evidence for the a_{1}(1260), nor the pi_{1}(1600) exotic state at the expected levels. An upper limit of 13.5 nb is determined for the exotic pi_{1}(1600) cross section, less than 2% of the a_{2}(1320) production. PMID:19392105

  4. The estimation of production rates of {\\pi }^{+}{K}^{-}, {\\pi }^{-}{K}^{+} and {\\pi }^{+}{\\pi }^{-} atoms in proton–nucleus interactions at 450 GeV c–1

    NASA Astrophysics Data System (ADS)

    Gorchakov, O. E.; Nemenov, L. L.

    2016-09-01

    Short-lived (τ ∼ 3× {10}-15 s) {π }+{K}-, {K}+{π }- and {π }+{π }- atoms as well as long-lived (τ ≥slant 1× {10}-11 s) {π }+{π }- atoms produced in proton–nucleus interactions at 24 GeV c–1 are observed and studied in the DIRAC experiment at the CERN Proton Synchroton. The purpose of this paper is to show that the yields of the short-lived {π }+{K}-, {K}+{π }- and {π }+{π }- atoms in proton–nucleus interactions at 450 GeV c–1 and {θ }{{lab}}=4^\\circ are estimated to be, respectively 67 ± 13, 31 ± 6 and 15 ± 2 times higher. This may allow a significant improvement of the precision of their lifetime measurement and π π and π K scattering length combinations | {a}0-{a}2| and | {a}1/2-{a}3/2| . The yields of the long-lived {π }+{K}-, {K}+{π }- and {π }+{π }- atoms at 450 GeV c–1 are estimated to be 265 ± 53, 120 ± 24 and 60 ± 9 times higher per time unit than at 24 GeV c–1. This may allow the resonance method to be used for measuring the Lamb shift in the π π atom and a new π π scattering length combination 2{a}0+{a}2 to be obtained.

  5. The f0 Mesons in Processes pi][pi [right arrow] [pi][pi], KK

    NASA Astrophysics Data System (ADS)

    Surovtsev, Yu. S.; Krupa, D.; Nagy, M.

    2002-06-01

    Combined analysis the experimental data on the processes pi][pi [right arrow] pi][pi, KK in the channel with IGJPC = 0+0++ in a model-independent approach leads to the following results: 1) The f0(665) state with properties of the sigma-meson is proved to exist; 2) It is shown that the f0(980) and especially f0(1370) (if exists) have a dominant ss component; 3) Indications for the glueball nature of the f0(1500) and for the considerable ss component in the f0(1710) are obtained; 4) Conclusion on the linear realization of chiral symmetry (chiS) is drawn.

  6. Observation of Upsilon(4S) decays to pi(+)pi(-)Upsilon(1S) and pi(+)pi(-)Upsilon(2S).

    PubMed

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

    2006-06-16

    Observation of Upsilon(4S) decays to pi(+)pi(-)C and pi(+)pi(-)Upsilon(2S)We present the first measurement of Upsilon(4S) decays to pi(+)pi(-)Upsilon(1S) based on a sample of 230 x 106(4S) mesons collected with the BABAR detector. We measure the product branching fractions Beta(Upsilon(4S) --> pi(+)pi(-)Upsilon(1S)) x BetaUpsilon(1S) --> mu(+)mu(-) = (2.23 +/- 0.25(stat) +/- 0.27(syst))x 10(-6) and Beta(Upsilon(4S) --> pi(+)pi(-)Upsilon(2S) x Beta(Upsilon(2S) --> mu(+)mu(-))=(1.69 +/-0.26(stat) +/- 0.20(syst)) x 10(-)6, from which we derive the partial widths Gamma(Upsilon(4S) --> pi(+)pi(-)Upsilon(1S))=(1.8 +/-0.4) keV and Gamma(Upsilon(4S) --> pi(+)pi(-)Upsilon(2S))=(2.7 +/- 0.8) keV. PMID:16803371

  7. Reexamining B{yields}{pi}{pi}, {pi}K decays in QCD factorization approach

    SciTech Connect

    Li Xinqiang; Yang Yadong

    2005-10-01

    Motivated by the recent experimental data, we have revisited the B{yields}{pi}K,{pi}{pi} decays in the framework of QCD factorization, with inclusion of the important strong penguin corrections of order {alpha}{sub s}{sup 2} induced by b{yields}Dg*g* (D=d or s and g* denotes an off-shell gluon) transitions. We find that these higher order strong penguin contributions can provide {approx}30% enhancement to the penguin-dominated B{yields}{pi}K decay rates, and such an enhancement can improve the consistency between the theoretical predictions and the experimental data significantly, while for the tree-dominated B{yields}{pi}{pi} decays, these higher order contributions play only a minor role. When these strong penguin contributions are summed, only a small strong phase remains and the direct CP asymmetries get small corrections. We also find that patterns of the ratios between the CP-averaged branching fractions remain nearly unaffected even after including these higher order corrections and the {pi}K puzzle still persists. Our results may indicate that to resolve the puzzle one would have to resort to new physics contributions in the electroweak penguin sector as found by Buras et al.

  8. Exclusive Central pi+pi- production in CDF

    SciTech Connect

    Albrow, Michael; Swiech, Artur; Zurek, Maria

    2013-10-14

    Using the Collider Detector at Fermilab, CDF, we have measured exclusive pi+pi- production at sqrt(s) = 900 GeV and 1960 GeV. The pi+pi- pair is central, |y| < 1.0, and there are no other particles detected in |eta| < 5.9. We discuss the mass spectrum, showing f0(980) and f2(1270) resonances, s-dependence, pT-dependence, and angular distributions.

  9. Effect of unitarization on the amplitudes for the decays K{sub 1}{sup 0} {sup {yields} {pi}+{pi}-} and K{sup +} {sup {yields} {pi}+{pi}+{pi}-}

    SciTech Connect

    Shabalin, E. P.

    2010-11-15

    The unitarization of the amplitude for the decay process K{sub 1}{sup 0} {sup {yields} {pi}+{pi}-} and allowance for the rescattering of final-state pions in the decay process K{sup +} {sup {yields} {pi}+{pi}+{pi}-} make it possible to evaluate, by using the parameters extracted from data on K {sup {yields}}2{pi} decays, the K{sup +} {sup {yields} {pi}+{pi}+{pi}-} decay width. The result agrees with the experimental width value at a level of a few percent. Allowance for corrections for higher order terms of the momentum expansion of the amplitude for the decay process K{sup +} {sup {yields} {pi}+{pi}+{pi}-} leads to the slope-parameter value of g{sub ++-}{sup th} = 0.2182, which agrees with its experimental counterpart, g{sub ++-}{sup exp} = 0.2154 {+-} 0.0035.

  10. Analytical {pi}{pi} scattering amplitude and the light scalars

    SciTech Connect

    Achasov, N. N.; Kiselev, A. V.

    2011-03-01

    In this work we construct the {pi}{pi} scattering amplitude T{sub 0}{sup 0} with regular analytical properties in the s complex plane, which describes simultaneously the data on the {pi}{pi} scattering, {phi}{yields}{pi}{sup 0}{pi}0{gamma} decay, and {pi}{pi}{yields}KK reaction. The chiral shielding of the {sigma}(600) meson and its mixing with the f{sub 0}(980) meson are also taken into account. The data agrees with the four-quark nature of the {sigma}(600) and f{sub 0}(980) mesons. The amplitude in the range -5m{sub {pi}}{sup 2}

  11. Stacking interactions and DNA intercalation

    SciTech Connect

    Li, Dr. Shen; Cooper, Valentino R; Thonhauser, Prof. Timo; Lundqvist, Prof. Bengt I.; Langreth, David C.

    2009-01-01

    The relationship between stacking interactions and the intercalation of proflavine and ellipticine within DNA is investigated using a nonempirical van der Waals density functional for the correlation energy. Our results, employing a binary stack model, highlight fundamental, qualitative differences between base-pair base-pair interactions and that of the stacked intercalator base pair system. Most notable result is the paucity of torque which so distinctively defines the Twist of DNA. Surprisingly, this model, when combined with a constraint on the twist of the surrounding base-pair steps to match the observed unwinding of the sugar-phosphate backbone, was sufficient for explaining the experimentally observed proflavine intercalator configuration. Our extensive mapping of the potential energy surface of base-pair intercalator interactions can provide valuable information for future nonempirical studies of DNA intercalation dynamics.

  12. Crystal engineering using bisphenols and trisphenols. Complexes with 1,10-phenanthroline: hydrogen-bonded chains in adducts with 4,4'-biphenol (1/1) and 4,4'-sulfonyldiphenol (2/3), pi-pi stacked chains in the (1/2) adduct with 4,4'-thiodiphenol, and pairwise-interwoven nets in 1,1,1-tris(4-hydroxyphenyl)ethane-1,10-phenanthroline-methanol (1/1/1).

    PubMed

    Ferguson; Glidewell; Lavender

    1999-08-01

    In 4,4'-biphenol-1,10-phenanthroline (1/1) [systematic name: 4,4'-biphenyldiol-1,10-phenanthroline (1/1)] the diphenol molecules lie across centres of inversion and the phenanthroline molecules lie across twofold rotation axes; the phenanthroline molecules act as chain-building units and the molecular components are linked into steeply zigzag C(16) chains parallel to [101] by means of O-H.N hydrogen bonds. In the structure of 4,4'-thiodiphenol-1,10-phenanthroline (1/2) the phenanthroline molecules act as chain-terminating units; the supramolecular aggregation is finite, with the bisphenol linked to each phenanthroline molecule by means of a single O-H.N hydrogen bond. pi-pi stacking interactions between the phenanthroline molecules in neighbouring hydrogen-bonded aggregates serve to link these aggregates into a continuous two-dimensional array. The phenanthroline molecules in 4,4'-sulfonyldiphenol-1,10-phenanthroline (2/3) play two roles: molecules in general positions act as chain-terminating units and are linked to the sulfonyldiphenol molecules by means of three-centre O-H.(N)(2) hydrogen bonds, while those lying across twofold rotation axes act as chain builders and are linked to two different sulfonyldiphenol molecules by means of a two-centre O-H.N hydrogen bond in each case; the resulting U-shaped five-component aggregates are further linked by C-H.O=S hydrogen bonds into a C(3)(3)(17)[R(2)(2)(12)] 'chain of rings' along [001]. In 1,1,1-tris(4-hydroxyphenyl)ethane-1,10-phenanthroline-methanol (1/1/1) [systematic name: 4,4',4"-ethylidynetriphenol-1,10-phenanthroline-methanol (1/1/1)] the phenanthroline molecules again act as chain-terminating units: the trisphenol molecules and the methanol molecules are linked by O-H.O hydrogen bonds into two-dimensional nets built from R(6)(6)(42) rings, and pairs of these nets are interwoven. The formation of each net utilizes two hydroxyl groups per trisphenol molecule as hydrogen-bond donors and the remaining hydroxyl

  13. Possible resolution of the B{yields}{pi}{pi}, {pi}K puzzles

    SciTech Connect

    Li Hsiangnan; Mishima, Satoshi

    2011-02-01

    We show that there exist uncanceled soft divergences in the k{sub T} factorization for nonfactorizable amplitudes of two-body nonleptonic B meson decays, similar to those identified in hadron hadroproduction. These divergences can be grouped into a soft factor using the eikonal approximation, which is then treated as an additional nonperturbative input in the perturbative QCD formalism. Viewing the special role of the pion as a qq bound state and as a pseudo Nambu-Goldstone boson, we postulate that the soft effect associated with it is significant. This soft factor enhances the nonfactorizable color-suppressed tree amplitudes, such that the branching ratios B({pi}{sup 0}{pi}{sup 0}) and B({pi}{sup 0}{rho}{sup 0}) are increased under the constraint of the B({rho}{sup 0}{rho}{sup 0}) data, the difference between the direct CP asymmetries A{sub CP}({pi}{sup {+-}}K{sup {+-}}) and A{sub CP}({pi}{sup 0}K{sup {+-}}) is enlarged, and the mixing-induced CP asymmetry S{sub {pi}}{sup 0}{sub K{sub S}} is reduced. Namely, the known {pi}{pi} and {pi}K puzzles can be resolved simultaneously.

  14. Puzzles in B{yields}{pi}{pi},{pi}K decays: Possible implications for R-parity violating supersymmetry

    SciTech Connect

    Yang Yadong; Wang, Rumin; Lu, G.R.

    2006-01-01

    Recent experiments suggest that certain data of B{yields}{pi}{pi},{pi}K decays are inconsistent with the standard model expectations. We try to explain the discrepancies with R-parity violating supersymmetry. By employing the QCD factorization approach, we study these decays in the minimal supersymmetric standard model with R-parity violation. We show that R-parity violation can resolve the discrepancies in both B{yields}{pi}{pi} and B{yields}{pi}K decays, and find that in some regions of parameter space all these requirements, including the CP averaged branching ratios and the direct CP asymmetries, can be satisfied. Furthermore, we have derived stringent bounds on relevant R-parity violating couplings from the latest experimental data, and some of these constraints are stronger than the existing bounds.

  15. Hadronic decays of the tau lepton : {tau}- {yields} ({pi}{pi}{pi})- {nu}{tau} within Resonance Chiral Theory

    SciTech Connect

    Gomez Dumm, D.; Pich, A.; Portoles, J.

    2006-01-12

    {tau} decays into hadrons foresee the study of the hadronization of vector and axial-vector QCD currents, yielding relevant information on the dynamics of the resonances entering into the processes. We analyse {tau} {yields} {pi}{pi}{pi}{nu}{tau} decays within the framework of the Resonance Chiral Theory, comparing this theoretical scheme with the experimental data, namely ALEPH spectral function and branching ratio. Hence we get values for the mass and on-shell width of the a 1 (1260) resonance, and provide the structure functions that have been measured by OPAL and CLEO-II.

  16. Dynamical coupled-channels study of {pi}N{yields}{pi}{pi}N reactions

    SciTech Connect

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

    2009-02-15

    As a step toward performing a complete coupled-channels analysis of the world data of {pi}N,{gamma}*N{yields}{pi}N,{eta}N,{pi}{pi}N reactions, the {pi}N{yields}{pi}{pi}N reactions are investigated starting with the dynamical coupled-channels model developed in Phys. Rev. C 76, 065201 (2007). The channels included are {pi}N,{eta}N, and {pi}{pi}N which has {pi}{delta},{rho}N, and {sigma}N resonant components. The nonresonant amplitudes are generated from solving a set of coupled-channels equations with the meson-baryon potentials defined by effective Lagrangians. The resonant amplitudes are generated from 16 bare excited nucleon (N*) states that are dressed by the nonresonant interactions as constrained by the unitarity condition. The data of total cross sections and {pi}N and {pi}{pi} invariant mass distributions of {pi}{sup +}p{yields}{pi}{sup +}{pi}{sup +}n,{pi}{sup +}{pi}{sup 0}p and {pi}{sup -}p{yields}{pi}{sup +}{pi}{sup -}n,{pi}{sup -}{pi}{sup 0}p,{pi}{sup 0}{pi}{sup 0}n reactions from threshold to the invariant mass W=2 GeV can be described to a very large extent. We show the importance of the coupled-channels effects and the strong interference among the contributions from the {pi}{delta},{sigma}N, and {rho}N channels. The large interference between the resonant and nonresonant amplitudes is also demonstrated. Possible future developments are discussed.

  17. Testing the dynamics of B ->pi pi and constraints onalpha

    SciTech Connect

    Grossman, Yuval; Hocker, Andreas; Ligeti, Zoltan; Pirjol, Dan

    2005-07-07

    In charmless nonleptonic B decays to {pi}{pi} or {rho}{rho}, the ''color allowed'' and ''color suppressed'' tree amplitudes can be studied in a systematic expansion in {alpha}{sub s}(m{sub b}) and {Lambda}{sub QCD}/m{sub b}. At leading order in this expansion their relative strong phase vanishes. The implications of this prediction are obscured by penguin contributions. They propose to use this prediction to test the relative importance of the various penguin amplitudes using experimental data. The present B {yields} {pi}{pi} data suggest that there are large corrections to the heavy quark limit, which can be due to power corrections to the tree amplitudes, large up-penguin amplitude, or enhanced weak annihilation. Because the penguin contributions are smaller, the heavy quark limit is more consistent with the B {yields} {rho}{rho} data, and its implications may become important for the extraction of {alpha} from this mode in the future.

  18. Dispersion relation bounds for {pi}{pi} scattering

    SciTech Connect

    Manohar, Aneesh V.; Mateu, Vicent

    2008-05-01

    Axiomatic principles such as analyticity, unitarity, and crossing symmetry constrain the second derivative of the {pi}{pi} scattering amplitudes in some channels to be positive in a region of the Mandelstam plane. Since this region lies in the domain of validity of chiral perturbation theory, we can use these positivity conditions to bound linear combinations of l{sub 1} and l{sub 2}. We compare our predictions with those derived previously in the literature using similar methods. We compute the one-loop {pi}{pi} scattering amplitude in the linear sigma model (LSM) using the MS scheme, a result hitherto absent in the literature. The LSM values for l{sub 1} and l{sub 2} violate the bounds for small values of m{sub {sigma}}/m{sub {pi}}. We show how this can occur, while still being consistent with the axiomatic principles.

  19. Photoproduction of $\\pi^+ \\pi^-$ meson pairs on the proton

    SciTech Connect

    Marco A. Battaglieri; DeVita, Raffaella; Szczepaniak, Adam P.

    2009-10-01

    The exclusive reaction $\\gamma p \\to p \\pi^+ \\pi^-$ was studied in the photon energy range 3.0 - 3.8 GeV and momentum transfer range $0.4<-t<1.0$ GeV$^2$. Data were collected with the CLAS detector at the Thomas Jefferson National Accelerator Facility. In this kinematic range the integrated luminosity was about 20 pb$^{-1}$. The reaction was isolated by detecting the $\\pi^+$ and proton in CLAS, and reconstructing the $\\pi^-$ via the missing-mass technique. Moments of the di-pion decay angular distributions were derived from the experimental data. Differential cross sections for the $S$, $P$, and $D$-waves in the $M_{\\pi^+\\pi^-}$ mass range $0.4-1.4$ GeV were derived performing a partial wave expansion of the extracted moments. Besides the dominant contribution of the $\\rho(770)$ meson in the $P$-wave, evidence for the $f_0(980)$ and the $f_2(1270)$ mesons was found in the $S$ and $D$-waves, respectively. The differential production cross sections $d\\sigma/dt$ for individual waves in the mass range of the above-mentioned mesons were extracted. This is the first time the $f_0(980)$ has been measured in a photoproduction experiment.

  20. Nonfactorizable Contributions to B {yields} {pi}{pi} Decays

    SciTech Connect

    Feldmann, T.

    2004-09-17

    We investigate to what extent the experimental information on B {yields} {pi}{pi} branching fractions and CP asymmetries can be used to better understand the QCD dynamics in these decays. For this purpose we decompose the independent isospin amplitudes into factorizable and non-factorizable contributions. The former can be estimated within the framework of QCD factorization for exclusive B decays. The latter vanish in the heavy-quark limit, m{sub b} {yields} {infinity}, and are treated as unknown hadronic parameters. We discuss at some length in which way the non-factorizable contributions are treated in different theoretical and phenomenological frameworks. We point out the potential differences between the phenomenological treatment of power-corrections in the ''BBNS approach'', and the appearance of power-suppressed operators in soft-collinear effective theory (SCET). On that basis we define a handful of different (but generic) scenarios where the non-factorizable part of isospin amplitudes is parameterized in terms of three or four unknowns, which can be constrained by data. We also give some short discussion on the implications of our analysis for B {yields} {pi}K decays. In particular, since non-factorizable QCD effects in B {yields} {pi}{pi} may be large, we cannot exclude sizeable non-factorizable effects, which violate SU(3){sub F} flavour symmetry, or even isospin symmetry (via long-distance QED effects). This may help to explain certain puzzles in connection with isospin-violating observables in B {yields} {pi}K decays.

  1. Study of the D0 \\to Pi Pi- Pi0 Decay at BaBar

    SciTech Connect

    Gaspero, Mario; /Rome U. /INFN, Rome

    2012-04-06

    The Dalitz-plot of the decay D{sup 0} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0} measured by the BABAR collaboration shows the structure of a final state having quantum numbers I{sup G}J{sup PC} = 0{sup -}0{sup 2-}. An isospin analysis of this Dalitz-plot finds that the fraction of the I = 0 contribution is about 96%. This high I = 0 contribution is unexpected because the weak interaction violates the isospin.

  2. Stacking interactions in PUF-RNA complexes

    SciTech Connect

    Yiling Koh, Yvonne; Wang, Yeming; Qiu, Chen; Opperman, Laura; Gross, Leah; Tanaka Hall, Traci M; Wickens, Marvin

    2012-07-02

    Stacking interactions between amino acids and bases are common in RNA-protein interactions. Many proteins that regulate mRNAs interact with single-stranded RNA elements in the 3' UTR (3'-untranslated region) of their targets. PUF proteins are exemplary. Here we focus on complexes formed between a Caenorhabditis elegans PUF protein, FBF, and its cognate RNAs. Stacking interactions are particularly prominent and involve every RNA base in the recognition element. To assess the contribution of stacking interactions to formation of the RNA-protein complex, we combine in vivo selection experiments with site-directed mutagenesis, biochemistry, and structural analysis. Our results reveal that the identities of stacking amino acids in FBF affect both the affinity and specificity of the RNA-protein interaction. Substitutions in amino acid side chains can restrict or broaden RNA specificity. We conclude that the identities of stacking residues are important in achieving the natural specificities of PUF proteins. Similarly, in PUF proteins engineered to bind new RNA sequences, the identity of stacking residues may contribute to 'target' versus 'off-target' interactions, and thus be an important consideration in the design of proteins with new specificities.

  3. Boron- and Nitrogen-Doped Phenalenyls: Unexpected 2e/ and 4e/all-sites pi-pi Covalency and Genuine Pancake Double Bonding

    DOE PAGESBeta

    Tian, Yong-Hui; Huang, Jingsong; Sumpter, Bobby G

    2015-01-01

    Phenalenyl is an important neutral pi-radical due to its capability to form unconventional pancake pi-pi bonding interactions, whereas its analogues with graphitic boron (B) or nitrogen (N)-doping have been regarded as closed-shell systems and therefore received much less attention. By using high-level quantum chemistry calculations, we show that the B- and N-doped closed-shell phenalenyls unexpectedly form open-shell singlet pi-dimers with diradicaloid character featuring 2e/all-sites double pi-pi bonding. Moreover, by proper substitutions, the doped phenalenyl derivatives can be made open-shell species that form closed shell singlet pi-dimers bound by stronger 4e/all-sites double pi-pi bonding. The covalent pi-pi bonding overlap is distributedmore » on all of the atomic sites giving robust and genuine pancake-shaped pi-dimers which, depending on the number of electrons available in the bonding interactions, are equally or more stable than the pi-dimers of the pristine phenalenyl.« less

  4. Measuring the Photon Polarization in Radiative B --> K-pi-pi-gamma

    SciTech Connect

    Gronau, Michael

    2001-08-13

    We propose a way of measuring the photon polarization in radiative B decays into K resonance states decaying to K{pi}{pi}, which can test the Standard Model and probe new physics. The photon polarization is shown to be measured by the up-down asymmetry of the photon direction relative to the K{pi}{pi} decay plane in the K resonance rest frame. The integrated asymmetry in K{sub 1}(1400) {yields} K{pi}{pi}, calculated to be 0.25, is measurable at currently operating B factories.

  5. Scalar mesons in. pi pi. and K-barK: Results of a unitary amplitude analysis

    SciTech Connect

    Wicklund, A.B.; Ayres, D.S.; Cohen, D.; Diebold, R.; Pawlicki, A.J.

    1980-11-03

    The ..pi pi -->..K-barK S wave has been extracted from an amplitude analysis of K-barK production. With use of unitarity constraints, evidence has been found for a resonance in ..pi pi -->..K-barK at 1425 +- 14 MeV/c/sup 2/ having a width 160 +- 30 MeV/c/sup 2/; this state is a likely candidate for the QQ-bar, J/sup P/C=0/sup + +/ nonet. It is shown that the S*(980), which is a background to this resonance, must be a very broad effect and is likely a K-barK virtual bound state.

  6. Determination of the S-Wave Pi Pi Scattering Lengths From a Study of K - to Pi - Pi0 Pi0 Decays

    SciTech Connect

    Batley, J.R.; Culling, A.J.; Kalmus, G.; Lazzeroni, C.; Munday, D.J.; Slater, M.W.; Wotton, S.A.; Arcidiacono, R.; Bocquet, G.; Cabibbo, N.; Ceccucci, A.; Cundy, D.; Falaleev, V.; Fidecaro, M.; Gatignon, L.; Gonidec, A.; Kubischta, W.; Norton, A.; Maier, A.; Patel, M.; Peters, A.; /CERN /Dubna, JINR /Pisa, Scuola Normale Superiore /Dubna, JINR /Dubna, JINR /Birmingham U. /Dubna, JINR /CERN /Dubna, JINR /Dubna, JINR /Sofiya U. /Dubna, JINR /Dubna, JINR /Dubna, JINR /INFN, Perugia /Dubna, JINR /Dubna, JINR /Northwestern U. /Dubna, JINR /Chicago U., EFI /Marseille, CPPM /Chicago U., EFI /Edinburgh U. /George Mason U. /Edinburgh U. /Ferrara U. /INFN, Ferrara /Florence U. /INFN, Florence /Florence U. /INFN, Florence /Pisa, Scuola Normale Superiore /INFN, Florence /Modena U. /INFN, Florence /INFN, Florence /Urbino U. /INFN, Florence /Mainz U., Inst. Phys. /Bonn U. /Mainz U., Inst. Phys. /Northwestern U. /SLAC /Northwestern U. /Northwestern U. /Royal Holloway, U. of London /Northwestern U. /Northwestern U. /UCLA /Perugia U. /INFN, Perugia /Frascati /Perugia U. /INFN, Perugia /INFN, Perugia /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa U. /INFN, Pisa /Barcelona, IFAE /Pisa U. /INFN, Pisa /DSM, DAPNIA, Saclay /DSM, DAPNIA, Saclay /CERN /DSM, DAPNIA, Saclay /Siegen U. /INFN, Turin /Turin U. /INFN, Turin /Bern U. /Turin U. /INFN, Turin /CERN /Turin U. /INFN, Turin /Madrid, CIEMAT /Vienna, OAW

    2012-03-29

    We report the results from a study of the full sample of {approx}6.031 x 10{sup 7} K{sup {+-}} {yields} {pi}{sup {+-}}{pi}{sup 0}{pi}{sup 0} decays recorded by the NA48/2 experiment at the CERN SPS. As first observed in this experiment, the {pi}{sup 0}{pi}{sup 0} invariant mass (M{sub 00}) distribution shows a cusp-like anomaly in the region around M{sub 00} = 2m{sub +}, where m{sub +} is the charged pion mass. This anomaly has been interpreted as an effect due mainly to the final state charge exchange scattering process {pi}{sup +}{pi}{sup -} {yields} {pi}{sup 0}{pi}{sup 0} in K{sup {+-}} {yields} {pi}{sup {+-}}{pi}{sup +}{pi}{sup -} decay. Fits to the M{sub 00} distribution using two different theoretical formulations provide the presently most precise determination of a{sub 0} - a{sub 2}, the difference between the {pi}{pi} S-wave scattering lengths in the isospin I = 0 and I = 2 states. Higher-order {pi}{pi} rescattering terms, included in the two formulations, allow also an independent, though less precise, determination of a{sub 2}.

  7. Testing the dynamics of B{yields}{pi}{pi} and constraints on {alpha}

    SciTech Connect

    Grossman, Yuval; Hoecker, Andreas; Ligeti, Zoltan; Pirjol, Dan

    2005-11-01

    In charmless nonleptonic B decays to {pi}{pi} or {rho}{rho}, the 'color allowed' and 'color suppressed' tree amplitudes can be studied in a systematic expansion in {alpha}{sub s}(m{sub b}) and {lambda}{sub QCD}/m{sub b}. At leading order in this expansion their relative strong phase vanishes. The implications of this prediction are obscured by penguin contributions. We propose to use this prediction to test the relative importance of the various penguin amplitudes using experimental data. The present B{yields}{pi}{pi} data suggest that there are large corrections to the heavy quark limit, which can be due to power corrections to the tree amplitudes, large up-penguin amplitude, or enhanced weak annihilation. Because the penguin contributions are smaller, the heavy quark limit is more consistent with the B{yields}{rho}{rho} data, and its implications may become important for the extraction of {alpha} from this mode in the future.

  8. B {sup {yields}} {pi}{pi} decays: Branching ratios and CP asymmetries

    SciTech Connect

    Kaidalov, A. B. Vysotsky, M. I.

    2007-04-15

    Theoretically motivated smallness of the penguin amplitude in B {sup {yields}} {pi}{pi} decays allows one to calculate the value of the unitarity-triangle angle {alpha}(o{sub 2}) with good accuracy. The relatively large branching ratio of the decay into {pi}{sup 0}{pi}{sup 0} is explained by the large value of FSI phase difference between decay amplitudes with I = 0 and I = 2.

  9. Measurement of direct photon emission in K+-->pi(+)pi(0)gamma decay

    PubMed

    Adler; Aoki; Ardebili; Atiya; Bergbusch; Blackmore; Bryman; Chiang; Convery; Diwan; Frank; Haggerty; Inagaki; Ito; Kabe; Kettell; Kishi; Kitching; Kobayashi; Komatsubara; Konaka; Kuno; Kuriki; Kycia; Li; Littenberg

    2000-12-01

    We have performed a measurement of the K+-->pi(+)pi(0)gamma decay and have observed 2x10(4) events. The best fit to the decay spectrum gives a branching ratio for direct photon emission of (4.7+/-0.8+/-0. 3)x10(-6) in the pi(+) kinetic energy region of 55 to 90 MeV and requires no component due to interference with inner bremsstrahlung. PMID:11102135

  10. Large electroweak penguin contribution in B{yields}K{pi} and {pi}{pi} decay modes

    SciTech Connect

    Mishima, Satoshi; Yoshikawa, Tadashi

    2004-11-01

    We discuss a possibility of large electroweak penguin contribution in B{yields}K{pi} and {pi}{pi} from recent experimental data. The experimental data may be suggesting that there are some discrepancies between the data and theoretical estimation in the branching ratios of them. In B{yields}K{pi} decays, to explain it, a large electroweak penguin contribution and large strong phase differences seem to be needed. The contributions should appear also in B{yields}{pi}{pi}. We show, as an example, a solution to solve the discrepancies in both B{yields}K{pi} and B{yields}{pi}{pi}. However the magnitude of the parameters and the strong phase estimated from experimental data are quite large compared with the theoretical estimations. It may be suggesting some new physics effects are included in these processes. We will have to discuss about the dependence of the new physics. To explain both modes at once, we may need large electroweak penguin contribution with new weak phases and some SU(3) breaking effects by new physics in both QCD and electroweak penguin-type processes.

  11. Reaction {pi}N {yields} {pi}{pi}N near threshold

    SciTech Connect

    Frlez, E.

    1993-11-01

    The LAMPF E1179 experiment used the {pi}{sup 0} spectrometer and an array of charged particle range counters to detect and record {pi}{sup +}{pi}{sup 0}, {pi}{sup 0}p, and {pi}{sup +}{pi}{sup 0}p coincidences following the reaction {pi}{sup +}p {yields} {pi}{sup 0}{pi}{sup +}p near threshold. The total cross sections for single pion production were measured at the incident pion kinetic energies 190, 200, 220, 240, and 260 MeV. Absolute normalizations were fixed by measuring {pi}{sup +}p elastic scattering at 260 MeV. A detailed analysis of the {pi}{sup 0} detection efficiency was performed using cosmic ray calibrations and pion single charge exchange measurements with a 30 MeV {pi}{sup {minus}} beam. All published data on {pi}N {yields} {pi}{pi}N, including our results, are simultaneously fitted to yield a common chiral symmetry breaking parameter {xi} ={minus}0.25{plus_minus}0.10. The threshold matrix element {vert_bar}{alpha}{sub 0}({pi}{sup 0}{pi}{sup +}p){vert_bar} determined by linear extrapolation yields the value of the s-wave isospin-2 {pi}{pi} scattering length {alpha}{sub 0}{sup 2}({pi}{pi}) = {minus}0.041{plus_minus}0.003 m{sub {pi}}{sup {minus}1}, within the framework of soft-pion theory.

  12. Observation of CP violation in B(0) --> K(+)pi(-) and B(0) --> pi(+)pi(-).

    PubMed

    Aubert, B; Bona, M; Boutigny, D; Karyotakis, Y; Lees, J P; Poireau, V; Prudent, X; Tisserand, V; Zghiche, A; Garra Tico, J; Grauges, E; Lopez, L; Palano, A; Eigen, G; Ofte, I; Stugu, B; Sun, L; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lopes Pegna, D; Lynch, G; Mir, L M; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Tackmann, K; Wenzel, W A; Del Amo Sanchez, P; Hawkes, C M; Watson, A T; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Schroeder, T; Steinke, M; Cottingham, W N; Walker, D; Asgeirsson, D J; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Saleem, M; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Liu, F; Long, O; Shen, B C; Zhang, L; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Schalk, T; Schumm, B A; Seiden, A; Williams, D C; Wilson, M G; Winstrom, L O; Chen, E; Cheng, C H; Dvoretskii, A; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Gabareen, A M; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Zeng, Q; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Brandt, T; Klose, V; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Lombardo, V; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Franchini, P; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Santoro, V; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Dauncey, P D; Flack, R L; Nash, J A; Nikolich, M B; Panduro Vazquez, W; Behera, P K; Chai, X; Charles, M J; Mallik, U; Meyer, N T; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gritsan, A V; Guo, Z J; Lae, C K; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Béquilleux, J; Davier, M; Grosdidier, G; Höcker, A; Lepeltier, V; Le Diberder, F; Lutz, A M; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wang, W F; Wormser, G; Lange, D J; Wright, D M; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; George, K A; Di Lodovico, F; Menges, W; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Jackson, P S; McMahon, T R; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Salvati, E; Saremi, S; Cowan, R; Fisher, P H; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; McLachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; De Nardo, G; Fabozzi, F; Lista, L; Monorchio, D; Sciacca, C; Baak, M A; Raven, G; Snoek, H L; Jessop, C P; Losecco, J M; Benelli, G; Corwin, L A; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Ter-Antonyan, R; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gagliardi, N; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Ben-Haim, E; Briand, H; Chauveau, J; David, P; Del Buono, L; de la Vaissière, Ch; Hamon, O; Hartfiel, B L; Leruste, Ph; Malclès, J; Ocariz, J; Perez, A; Gladney, L; Biasini, M; Covarelli, R; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Calderini, G; Carpinelli, M; Cenci, R; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Mazur, M A; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Haire, M; Biesiada, J; Elmer, P; Lau, Y P; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Baracchini, E; Bellini, F; Cavoto, G; D'Orazio, A; Del Re, D; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Renga, F; Voena, C; Ebert, M; Schröder, H; Waldi, R; Adye, T; Castelli, G; Franek, B; Olaiya, E O; Ricciardi, S; Roethel, W; Wilson, F F; Aleksan, R; Emery, S; Escalier, M; Gaidot, A; Ganzhur, S F; Hamel de Monchenault, G; Kozanecki, W; Legendre, M; Vasseur, G; Yèche, Ch; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Bechtle, P; Berger, N; Claus, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dujmic, D; Dunwoodie, W; Field, R C; Glanzman, T; Gowdy, S J; Graham, M T; Grenier, P; Hast, C; Hryn'ova, T; Innes, W R; Kelsey, M H; Kim, H; Kim, P; Leith, D W G S; Li, S; Luitz, S; Luth, V; Lynch, H L; Macfarlane, D B; Marsiske, H; Messner, R; Muller, D R; O'grady, C P; Perazzo, A; Perl, M; Pulliam, T; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Stelzer, J; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; van Bakel, N; Wagner, A P; Weaver, M; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Yi, K; Young, C C; Burchat, P R; Edwards, A J; Majewski, S A; Petersen, B A; Wilden, L; Ahmed, S; Alam, M S; Bula, R; Ernst, J A; Jain, V; Pan, B; Saeed, M A; Wappler, F R; Zain, S B; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Ritchie, J L; Ruland, A M; Schilling, C J; Schwitters, R F; Izen, J M; Lou, X C; Ye, S; Bianchi, F; Gallo, F; Gamba, D; Pelliccioni, M; Bomben, M; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martinez-Vidal, F; Milanes, D A; Oyanguren, A; Albert, J; Banerjee, Sw; Bhuyan, B; Hamano, K; Kowalewski, R; Nugent, I M; Roney, J M; Sobie, R J; Back, J J; Harrison, P F; Latham, T E; Mohanty, G B; Pappagallo, M; Band, H R; Chen, X; Dasu, S; Flood, K T; Hollar, J J; Kutter, P E; Pan, Y; Pierini, M; Prepost, R; Wu, S L; Yu, Z; Neal, H

    2007-07-13

    We report observations of CP violation in the decays B(0) --> K(+)pi(-) and B(0) --> pi(+)pi(-) in a sample of 383 x 10(6) Upsilon(4S) --> BB[over] events. We find 4372+/-82 B(0) --> K(+)pi(-) decays and measure the direct CP-violating charge asymmetry A(Kpi) = -0.107+/-0.018(stat)(-0.004)(+0.007)(syst), which excludes the CP-conserving hypothesis with a significance of 5.5 standard deviations. In the same sample, we find 1139+/-49 B(0) --> pi(+)pi(-) decays and measure the CP-violating asymmetries S(pipi) = -0.60+/-0.11(stat)+/-0.03(syst) and C(pipi) = -0.21+/-0.09(stat)+/-0.02(syst). CP conservation in B(0) --> pi(+)pi(-) (S(pipi) = C(pipi) = 0) is excluded at a confidence level 1-C.L. = 8 x 10(-8), corresponding to 5.4 standard deviations. PMID:17678212

  13. Exclusive Central $\\pi^{+}\\pi^{-}$ Production in Proton Antiproton Collisions at the CDF

    SciTech Connect

    Zurek, Maria

    2015-01-01

    Exclusive $\\pi^{=}\\pi^{-}$ production in proton-antiproton collisions at $\\sqrt{s}$ = 0.9 and 1.96 TeV in the Collider Detector at Fermilab has been measured. We select events with two particles with opposite charge in pseudorapidity region -1.3 < $\\eta$ < 1.3 with no other particles detected in -5.9 < $\\eta$ < 5.9. Particles are assumed to be pions. The $\\pi^{+}\\pi^{-}$system is required to have rapidity -1.0 < $y$ < 1.0. The data are expected to be dominated by the double pomeron exchange mechanism. Therefore, the quantum numbers of the central state are constrained. The data extend up to dipion mass M($\\pi^{+}\\pi^{-}$) = 5000 MeV/$c^2$. Resonance structures consistent with $f_0$ and $f_2$(1270) mesons are visible. The results are valuable for light hadron spectroscopy and for providing information about the nature of the pomeron in a region between non-perturbative and perturbative quantum chromodynamics

  14. Study of the anomalous process {gamma}{pi}{yields}{pi}{pi}

    SciTech Connect

    Roberts, C.D.; Alkofer, R.

    1995-08-01

    The {gamma}{pi} {yields} {pi}{pi} form factor, F{sup 3{pi}}(s), is calculated in generalized impulse approximation within the Dyson-Schwinger Equation framework. This is an anomalous process and as such its form is a fundamentally important characteristic of the quantum field theoretical structure of QCD because it signals the breaking of the U{sub A} symmetry by quantization. There is only one experimental measurement of F{sup 3{pi}}(s) at s {approximately} 8m{sub {pi}}{sup 2}, which has large errors, however, there is an approved experiment at CEBAF to study F{sup 3{pi}}(s) in the reaction {gamma}{pi}{sup +} {yields} {pi}{sup +}{pi}{sup 0} near threshold. This is to be done by measuring {gamma}p {yields} {pi}{sup +}{pi}{sup 0}n cross sections near t {approx_equal} {sup -}m{sub {pi}}{sup 2}. Present calculations of F{sup 3{pi}}(s) are either unrelated to QCD or rely on {open_quotes}low-energy{close_quotes} expansions. The approach we employ, which 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}, allows us to go beyond such {open_quotes}low-energy{close_quotes} expansions and relate F{sup 3{pi}}(s) to the structure of the effective quark-quark interaction in the infrared. Our preliminary results are encouraging. The chiral limit value, F{sup 3{pi}}(s=0), obtained in our approach agrees with that which one expects from the connection between anomalous processes and the quantization of QCD. Our results also indicate that the form factor grows smoothly away from the chiral point. Our detailed calculation will allow us to address the question of the reliability of the extrapolation to the pion mass shell that is necessary in interpreting the data.

  15. Simple description of {pi}{pi} scattering to 1 GeV

    SciTech Connect

    Harada, M.; Sannino, F.; Schechter, J.

    1996-08-01

    Motivated by the 1/{ital N}{sub {ital c}} expansion, we present a simple model of {pi}{pi} scattering as a sum of a {ital current}-{ital algebra} contact term and resonant pole exchanges. The model preserves crossing symmetry as well as unitarity up to 1.2 GeV. Key features include chiral dynamics, vector meson dominance, a broad low energy scalar ({sigma}) meson, and a {ital Ramsauer}-{ital Townsend} mechanism for the understanding of the 980 MeV region. We discuss in detail the {ital regularization} (corresponding to rescattering effects) necessary to make all these nice features work. {copyright} {ital 1996 The American Physical Society.}

  16. Search for CP violation in the decays D0 --> K- K+ and D0 --> pi- pi+.

    PubMed

    Aubert, B; Bona, M; Boutigny, D; Karyotakis, Y; Lees, J P; Poireau, V; Prudent, X; Tisserand, V; Zghiche, A; Garra Tico, J; Grauges, E; Lopez, L; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lopes Pegna, D; Lynch, G; Mir, L M; Orimoto, T J; Osipenkov, I L; Ronan, M T; Tackmann, K; Tanabe, T; Wenzel, W A; Del Amo Sanchez, P; Hawkes, C M; Watson, A T; Koch, H; Schroeder, T; Walker, D; Asgeirsson, D J; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Barrett, M; Khan, A; Saleem, M; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Liu, F; Long, O; Shen, B C; Vitug, G M; Zhang, L; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Schalk, T; Schumm, B A; Seiden, A; Wilson, M G; Winstrom, L O; Chen, E; Cheng, C H; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Gabareen, A M; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Klose, V; Kobel, M J; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Lombardo, V; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Watson, J E; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Franchini, P; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Santoro, V; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Dauncey, P D; Flack, R L; Nash, J A; Panduro Vazquez, W; Tibbetts, M; Behera, P K; Chai, X; Charles, M J; Mallik, U; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Lae, C K; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Béquilleux, J; D'Orazio, A; Davier, M; Grosdidier, G; Höcker, A; Lepeltier, V; Le Diberder, F; Lutz, A M; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wang, W F; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Burke, J P; Chavez, C A; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; George, K A; Di Lodovico, F; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Paramesvaran, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Bailey, D; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Salvati, E; Saremi, S; Cowan, R; Dujmic, D; Fisher, P H; Koeneke, K; Sciolla, G; Spitznagel, M; Taylor, F; Yamamoto, R K; Zhao, M; Zheng, Y; McLachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; De Nardo, G; Fabozzi, F; Lista, L; Monorchio, D; Sciacca, C; Baak, M A; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; Losecco, J M; Benelli, G; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Sekula, S J; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gagliardi, N; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Ben-Haim, E; Briand, H; Calderini, G; Chauveau, J; David, P; Del Buono, L; de la Vaissière, Ch; Hamon, O; Leruste, Ph; Malclès, J; Ocariz, J; Perez, A; Prendki, J; Gladney, L; Biasini, M; Covarelli, R; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Carpinelli, M; Cenci, R; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Mazur, M A; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Biesiada, J; Elmer, P; Lau, Y P; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Baracchini, E; Bellini, F; Cavoto, G; Del Re, D; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Renga, F; Voena, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Castelli, G; Franek, B; Olaiya, E O; Roethel, W; Wilson, F F; Emery, S; Escalier, M; Gaidot, A; Ganzhur, S F; Hamel de Monchenault, G; Kozanecki, W; Vasseur, G; Yèche, Ch; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; White, R M; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Bechtle, P; Claus, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Glanzman, T; Gowdy, S J; Graham, M T; Grenier, P; Hast, C; Innes, W R; Kaminski, J; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Luitz, S; Luth, V; Lynch, H L; Macfarlane, D B; Marsiske, H; Messner, R; Muller, D R; O'Grady, C P; Ofte, I; Perazzo, A; Perl, M; Pulliam, T; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; Wagner, A P; Weaver, M; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Yi, K; Young, C C; Ziegler, V; Burchat, P R; Edwards, A J; Majewski, S A; Miyashita, T S; Petersen, B A; Wilden, L; Ahmed, S; Alam, M S; Bula, R; Ernst, J A; Jain, V; Pan, B; Saeed, M A; Wappler, F R; Zain, S B; Krishnamurthy, M; Spanier, S M; Eckmann, R; Ritchie, J L; Ruland, A M; Schilling, C J; Schwitters, R F; Izen, J M; Lou, X C; Ye, S; Bianchi, F; Gallo, F; Gamba, D; Pelliccioni, M; Bomben, M; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martinez-Vidal, F; Milanes, D A; Oyanguren, A; Albert, J; Banerjee, Sw; Bhuyan, B; Hamano, K; Kowalewski, R; Nugent, I M; Roney, J M; Sobie, R J; Harrison, P F; Ilic, J; Latham, T E; Mohanty, G B; Band, H R; Chen, X; Dasu, S; Flood, K T; Hollar, J J; Kutter, P E; Pan, Y; Pierini, M; Prepost, R; Wu, S L; Neal, H

    2008-02-15

    We measure time-integrated CP-violating asymmetries of neutral charmed mesons in the modes D0 --> K(-) K(+) and D0 --> pi(-) pi(+) with the highest precision to date by using D0 --> K(-) pi(+) decays to correct detector asymmetries. An analysis of 385.8 fb(-1) of data collected with the BABAR detector yields values of a(CP)(KK)=(0.00+/-0.34(stat)+/-0.13(syst))% and a(CP)(pipi)=(-0.24+/-0.52(stat)+/-0.22(syst))%, which agree with standard model predictions. PMID:18352456

  17. Improved measurements of CP-violating asymmetry amplitudes in B0-->pi+pi- decays.

    PubMed

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

    2005-10-01

    We present updated measurements of the CP-violating parameters Spipi and Cpipi in B0-->pi+pi- decays. Using a sample of 227x10(6) Upsilon(4S)-->BB decays collected with the BABAR detector at the PEP-II asymmetric-energy e(+)e(-) collider at SLAC, we observe 467+/-33 signal decays and measure Spipi=-0.30+/-0.17(stat)+/-0.03(syst) and Cpipi=-0.09+/-0.15(stat)+/-0.04(syst). PMID:16241716

  18. The target asymmetry P_z in {gamma}p-->p{pi}^+{pi}^- with the CLAS spectrometer at Jefferson Laboratory

    SciTech Connect

    Sungkyun Park, CLAS Collaboration

    2012-04-01

    The study of baryon resonances provides a deeper understanding of the strong interaction because the dynamics and relevant degrees of freedom hidden within them are reflected by the properties of the excited states of baryons. Higher-lying excited states at and above 1.9 GeV/c{sup 2} are generally predicted to have strong couplings to the {pi}{pi}N final states via {pi}{Delta} or {rho}N intermediate states. Double-pion photoproduction is therefore important to find and investigate properties of highmass resonances. The CLAS g9a (FROST) experiment, as part of the N* spectroscopy program at Jefferson Laboratory (JLab), has accumulated photoproduction data using linearly- and circularly-polarized photons incident on a longitudinally-polarized butanol target in the photon energy range 0.3 to 2.4 GeV. In this contribution, the extraction of the target asymmetry for the reaction {gamma}p {yields} p{pi}{sup +}{pi}{sup -} will be described and preliminary results will be presented.

  19. Precision measurement of {pi}{pi} scattering lengths at the NA48/2 experiment

    SciTech Connect

    Venditti, Stefano

    2010-12-28

    The NA48/2 experiment at CERN [1] collected {approx}18{center_dot}10{sup 9} charged kaon decays during the years 2003/4. Along with the primary goals of the collaboration, i.e. the measurement of the CP-violating asymmetry in the K{sup {+-}}{yields}{pi}{sup {+-}}{pi}{sup +}{pi}{sup -} and K{sup {+-}}{yields}{pi}{sup {+-}}{pi}{sup 0}{pi}{sup 0} decays thanks to the simultaneous collection of K{sup +} and K{sup -} events, the collected data allowed to perform many other interesting analyses. In this paper two independent measurements of {pi}{pi} scattering lengths will be reviewed, using NA48/2 data from the K{sup {+-}}{yields}e{sup {+-}}{nu}{pi}{sup +}{pi}{sup -} decay and from the cusp effect in K{sup {+-}}{yields}{pi}{sup {+-}}{pi}{sup +}{pi}{sup -} respectively.

  20. The phase-shift of isospin-2 pi-pi scattering from lattice QCD

    SciTech Connect

    Jozef J. Dudek, Robert G. Edwards, Michael J. Peardon, David G. Richards, Christopher E. Thomas

    2011-04-01

    Finite-volume lattice QCD calculations offer the possibility of extracting resonance parameters from the energy-dependent elastic phase-shift computed using the L\\"uscher technique. In this letter, as a trial of the method, we report on the extraction of the non-resonant phase-shift for $S$ and $D$-wave $\\pi\\pi$ isospin-2 scattering from dynamical lattice QCD computations. We define a variational basis of operators resembling pairs of pions of definite relative momentum and extract a spectrum of excited states that maps to phase-shifts at a set of discrete scattering momenta. Computations are performed with pion masses between $400$ and $520$ MeV on multiple spatial volumes. We observe no significant quark mass dependence in the phase-shifts extracted which are in reasonable agreement with the available experimental data at low momentum.

  1. Phase shift of isospin-2 {pi}{pi} scattering from lattice QCD

    SciTech Connect

    Dudek, Jozef J.; Edwards, Robert G.; Richards, David G.; Thomas, Christopher E.; Peardon, Michael J.

    2011-04-01

    Finite-volume lattice QCD calculations offer the possibility of extracting resonance parameters from the energy-dependent elastic phase-shift computed using the Luescher technique. In this letter, as a trial of the method, we report on the extraction of the nonresonant phase-shift for S and D-wave {pi}{pi} isospin-2 scattering from dynamical lattice QCD computations. We define a variational basis of operators resembling pairs of pions of definite relative momentum and extract a spectrum of excited states that maps to phase-shifts at a set of discrete scattering momenta. Computations are performed with pion masses between 400 and 520 MeV on multiple spatial volumes. We observe no significant quark mass dependence in the phase-shifts extracted which are in reasonable agreement with the available experimental data at low momentum.

  2. Measuring the charged pion polarizability in the gamma gamma -> pi+pi- reaction

    SciTech Connect

    Lawrence, David W.; Miskimen, Rory A.; Mushkarenkov, Alexander Nikolaevich; Smith, Elton S.

    2013-08-01

    Development has begun of a new experiment to measure the charged pion polarizability $\\alpha_{\\pi}-\\beta_{\\pi}$. The charged pion polarizability ranks among the most important tests of low-energy QCD presently unresolved by experiment. Analogous to precision measurements of $\\pi^{\\circ}\\rightarrow\\gamma\\gamma$ that test the intrinsic odd-parity (anomalous) sector of QCD, the pion polarizability tests the intrinsic even-parity sector of QCD. The measurement will be performed using the $\\gamma\\gamma\\rightarrow\\pi^{+{}}\\pi^{-{}}$ cross section accessed via the Primakoff mechanism on nuclear targets using the GlueX detector in Hall D at Jefferson Lab. The linearly polarized photon source in Hall-D will be utilized to separate the Primakoff cross-section from coherent $\\rho^{\\circ}$ production.

  3. Edge-edge interactions in stacked graphene nanoplatelets

    SciTech Connect

    Cruz Silva, Eduardo; Terrones Maldonado, Humberto; Terrones Maldonado, Mauricio; Jia, Xiaoting; Sumpter, Bobby G; Dresselhaus, M; Meunier, V.

    2013-01-01

    High-resolution transmission electron microscopy (HRTEM) studies show the dynamics of small graphene platelets on larger graphene layers. The platelets move nearly freely to eventually lock in at well-defined positions close to the edges of the larger underlying graphene sheet. While such movement is driven by a shallow potential energy surface described by an interplane interaction, the lock-in position occurs by via edge-edge interactions of the platelet and the graphene surface located underneath. Here we quantitatively study this behavior using van der Waals density functional calculations. Local interactions at the open edges are found to dictate stacking configurations that are different from Bernal (AB) stacking. These stacking configurations are known to be otherwise absent in edge-free two-dimensional (2D) graphene. The results explain the experimentally observed platelet dynamics and provide a detailed account of the new electronic properties of these combined systems.

  4. Measurement of Branching Fractions and Mass Spectra of B to K pi pi gamma

    SciTech Connect

    Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; Grauges, E.; Palano, A.; Pappagallo, M.; Pompili, A.; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; Eigen, G.; Ofte, I.; Stugu, B. /Bergen U. /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /Pisa U. /Pisa, Scuola Normale Superiore /INFN, Pisa /Prairie View A-M /Princeton U. /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Vanderbilt U. /Victoria U. /Warwick U. /Wisconsin U., Madison /Yale U.

    2005-07-12

    The authors present a measurement of the partial branching fractions and mass spectra of the exclusive radiative penguin processes B {yields} K{pi}{pi}{gamma} in the range m{sub K{pi}{pi}} < 1.8 GeV/c{sup 2}. They reconstruct four final states: K{sup +}{pi}{sup -}{pi}{sup +}{gamma}, K{sup +}{pi}{sup -}{pi}{sup 0}{gamma}, K{sub S}{sup 0}{pi}{sup -}{pi}{sup +}{gamma}, and K{sub S}{sup 0}{pi}{sup +}{pi}{sup 0}{gamma}, where K{sub S}{sup 0} {yields} {pi}{sup +}{pi}{sup -}. Using 232 million e{sup +}e{sup -} {yields} B{bar B} events recorded by the BABAR experiment at the PEP-II asymmetric-energy storage ring, they measure the branching fractions {Beta}(B{sup +} {yields} K{sup +}{pi}{sup -}{pi}{sup +}{gamma}) = (2.95 {+-} 0.13(stat.) {+-} 0.20(syst)) x 10{sup -5}, {Beta}(B{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0}{gamma}) = (4.07 {+-} 0.22(stat.) {+-} 0.31(syst.)) x 10{sup -5}, {Beta}(B{sup 0} {yields} K{sup 0}{pi}{sup +}{pi}{sup -}{gamma}) = (1.85 {+-} 0.21(stat.) {+-} 0.12(syst.)) x 10{sup -5}, and {Beta}(B{sup +} {yields} K{sup 0}{pi}{sup +}{pi}{sup 0}{gamma}) = (4.56 {+-} 0.42(stat.) {+-} 0.31(syst.)) x 10{sup -5}.

  5. Tetraquark interpretation of the BELLE data on the anomalous Upsilon(1S)pi+ pi- and Upsilon(2S)pi+ pi- production near the Upsilon(5S) resonance.

    PubMed

    Ali, Ahmed; Hambrock, Christian; Aslam, M Jamil

    2010-04-23

    We analyze the Belle data [K. F. Chen (Belle Collaboration), Phys. Rev. Lett. 100, 112001 (2008); I. Adachi (Belle Collaboration), arXiv:0808.2445] on the processes e+ e- --> Upsilon(1S)pi+ pi-, Upsilon(2S)pi+ pi- near the peak of the Upsilon(5S) resonance, which are found to be anomalously large in rates compared to similar dipion transitions between the lower Upsilon resonances. Assuming these final states arise from the production and decays of the J(PC)=1(--) state Y(b)(10,890), which we interpret as a bound (diquark-antidiquark) tetraquark state [bq][bq], a dynamical model for the decays Y(b) --> Upsilon(1S)pi+ pi-, Upsilon(2S)pi+ pi- is presented. Depending on the phase space, these decays receive significant contributions from the scalar 0(++) states, f0(600) and f0(980), and from the 2(++) qq-meson f(2)(1270). Our model provides excellent fits for the decay distributions, supporting Y(b) as a tetraquark state. PMID:20482041

  6. Observation of CP Violation in B0 to K+pi- and B0 to pi+pi-

    SciTech Connect

    Aubert, B.

    2007-03-14

    The authors report observations of CP violation in the decays B{sup 0} {yields} K{sup +}{pi}{sup -} and B{sup 0} {yields} {pi}{sup +}{pi}{sup -} in a sample of 383 million {Upsilon}(4S) {yields} B{bar B} events. They find 4372 {+-} 82 B{sup 0} {yields} K{sup +}{pi}{sup -} decays and measure the direct Cp-violating charge asymmetry {Alpha}{sub K{pi}} = -0.107 {+-} 0.018(stat){sub -0.004}{sup +0.007}(syst), which excludes the CP-conserving hypothesis with a significance of 5.5 standard deviations. In the same sample they find 1139 {+-} 49 B{sup 0} {yields} {pi}{sup +}{pi}{sup -} decays and measure the CP-violating asymmetries S{sub {pi}{pi}} = -0.60 {+-} 0.11(stat) {+-} 0.03(syst) and C{sub {pi}{pi}} = -0.21 {+-} 0.09(stat) {+-} 0.02(syst). CP conservation in B{sup 0} {yields} {pi}{sup +}{pi}{sup -} (S{sub {pi}{pi}} = C{sub {pi}{pi}} = 0) is excluded at a confidence level 1-C.L. = 8 x 10{sup -8}, corresponding to 5.4 standard deviations.

  7. Interaction driven quantum Hall effect in artificially stacked graphene bilayers.

    PubMed

    Iqbal, Muhammad Zahir; Iqbal, Muhammad Waqas; Siddique, Salma; Khan, Muhammad Farooq; Ramay, Shahid Mahmood; Nam, Jungtae; Kim, Keun Soo; Eom, Jonghwa

    2016-01-01

    The honeycomb lattice structure of graphene gives rise to its exceptional electronic properties of linear dispersion relation and its chiral nature of charge carriers. The exceptional electronic properties of graphene stem from linear dispersion relation and chiral nature of charge carries, originating from its honeycomb lattice structure. Here, we address the quantum Hall effect in artificially stacked graphene bilayers and single layer graphene grown by chemical vapor deposition. The quantum Hall plateaus started to appear more than 3 T and became clearer at higher magnetic fields up to 9 T. Shubnikov-de Hass oscillations were manifestly observed in graphene bilayers texture. These unusual plateaus may have been due to the layers interaction in artificially stacked graphene bilayers. Our study initiates the understanding of interactions between artificially stacked graphene layers. PMID:27098387

  8. Interaction driven quantum Hall effect in artificially stacked graphene bilayers

    PubMed Central

    Iqbal, Muhammad Zahir; Iqbal, Muhammad Waqas; Siddique, Salma; Khan, Muhammad Farooq; Ramay, Shahid Mahmood; Nam, Jungtae; Kim, Keun Soo; Eom, Jonghwa

    2016-01-01

    The honeycomb lattice structure of graphene gives rise to its exceptional electronic properties of linear dispersion relation and its chiral nature of charge carriers. The exceptional electronic properties of graphene stem from linear dispersion relation and chiral nature of charge carries, originating from its honeycomb lattice structure. Here, we address the quantum Hall effect in artificially stacked graphene bilayers and single layer graphene grown by chemical vapor deposition. The quantum Hall plateaus started to appear more than 3 T and became clearer at higher magnetic fields up to 9 T. Shubnikov-de Hass oscillations were manifestly observed in graphene bilayers texture. These unusual plateaus may have been due to the layers interaction in artificially stacked graphene bilayers. Our study initiates the understanding of interactions between artificially stacked graphene layers. PMID:27098387

  9. Interaction driven quantum Hall effect in artificially stacked graphene bilayers

    NASA Astrophysics Data System (ADS)

    Iqbal, Muhammad Zahir; Iqbal, Muhammad Waqas; Siddique, Salma; Khan, Muhammad Farooq; Ramay, Shahid Mahmood; Nam, Jungtae; Kim, Keun Soo; Eom, Jonghwa

    2016-04-01

    The honeycomb lattice structure of graphene gives rise to its exceptional electronic properties of linear dispersion relation and its chiral nature of charge carriers. The exceptional electronic properties of graphene stem from linear dispersion relation and chiral nature of charge carries, originating from its honeycomb lattice structure. Here, we address the quantum Hall effect in artificially stacked graphene bilayers and single layer graphene grown by chemical vapor deposition. The quantum Hall plateaus started to appear more than 3 T and became clearer at higher magnetic fields up to 9 T. Shubnikov-de Hass oscillations were manifestly observed in graphene bilayers texture. These unusual plateaus may have been due to the layers interaction in artificially stacked graphene bilayers. Our study initiates the understanding of interactions between artificially stacked graphene layers.

  10. Combining information from B{yields}{pi}{pi} and B{yields}{pi}{rho},{pi}{omega} decays

    SciTech Connect

    Sowa, M.; Zenczykowski, P.

    2005-06-01

    We consider the B{yields}{pi}{pi} and B{yields}{pi}{rho},{pi}{omega} decays alongside each other, taking into account the contributions from all individual penguin amplitudes generated by the internal t, c, and u quarks. We argue that three ratios of penguin amplitudes, each for a different internal quark, formed by dividing the individual penguin amplitude in B{yields}{pi}{pi} by the corresponding amplitude in B{yields}{pi}{rho},{pi}{omega}, should be equal. We study the implications of the assumed existence of this connection between B{yields}{pi}{pi} and B{yields}{pi}{rho},{pi}{omega}. First, accepting that in the B{yields}{pi}{pi} decays the ratio C/T of the color-suppressed factorization amplitude C to the tree factorization amplitude T is negligible, we determine the ratio of individual penguin amplitudes. Then, from the B{yields}{pi}{rho},{pi}{omega} data, we extract the effective (i.e. possibly containing some penguin terms) tree and the effective color-suppressed amplitudes relevant for these processes, and the corresponding solutions for the factorization amplitudes. Finally, we argue that the C/T ratio in B{yields}{pi}{pi} should be identical to its counterpart in B{yields}{pi}{rho},{pi}{omega} (relevant for pion emission from the decaying b quark). This constraint permits the determination of C/T and of other amplitude ratios directly from the data. Although the |C/T| ratio extracted from the available data still carries a substantial error, it is consistent with the expected value of 0.25-0.5.

  11. Aromatic stacking interactions govern catalysis in aryl-alcohol oxidase.

    PubMed

    Ferreira, Patricia; Hernández-Ortega, Aitor; Lucas, Fátima; Carro, Juan; Herguedas, Beatriz; Borrelli, Kenneth W; Guallar, Victor; Martínez, Angel T; Medina, Milagros

    2015-08-01

    Aryl-alcohol oxidase (AAO, EC 1.1.3.7) generates H2 O2 for lignin degradation at the expense of benzylic and other π system-containing primary alcohols, which are oxidized to the corresponding aldehydes. Ligand diffusion studies on Pleurotus eryngii AAO showed a T-shaped stacking interaction between the Tyr92 side chain and the alcohol substrate at the catalytically competent position for concerted hydride and proton transfers. Bi-substrate kinetics analysis revealed that reactions with 3-chloro- or 3-fluorobenzyl alcohols (halogen substituents) proceed via a ping-pong mechanism. However, mono- and dimethoxylated substituents (in 4-methoxybenzyl and 3,4-dimethoxybenzyl alcohols) altered the mechanism and a ternary complex was formed. Electron-withdrawing substituents resulted in lower quantum mechanics stacking energies between aldehyde and the tyrosine side chain, contributing to product release, in agreement with the ping-pong mechanism observed in 3-chloro- and 3-fluorobenzyl alcohol kinetics analysis. In contrast, the higher stacking energies when electron donor substituents are present result in reaction of O2 with the flavin through a ternary complex, in agreement with the kinetics of methoxylated alcohols. The contribution of Tyr92 to the AAO reaction mechanism was investigated by calculation of stacking interaction energies and site-directed mutagenesis. Replacement of Tyr92 by phenylalanine does not alter the AAO kinetic constants (on 4-methoxybenzyl alcohol), most probably because the stacking interaction is still possible. However, introduction of a tryptophan residue at this position strongly reduced the affinity for the substrate (i.e. the pre-steady state Kd and steady-state Km increase by 150-fold and 75-fold, respectively), and therefore the steady-state catalytic efficiency, suggesting that proper stacking is impossible with this bulky residue. The above results confirm the role of Tyr92 in substrate binding, thus governing the kinetic mechanism

  12. Preferential pi-pi complexation between tamoxifen and borage oil/gamma linolenic acid: transcutaneous delivery and NMR spectral modulation.

    PubMed

    Heard, Charles M; Gallagher, Simon J; Congiatu, Costantino; Harwood, John; Thomas, Christopher P; McGuigan, Christopher; Nemcová, Marta; Nouskova, Tereza

    2005-09-30

    The effect of different proportions of borage oil on the in vitro transcutaneous delivery of tamoxifen were studied, with the aim of developing a gel capable of the simultaneous delivery of tamoxifen and gamma linolenic acid across (breast) skin. Supplementary work probed 1H NMR spectral data for tamoxifen in the presence of different proportions of polyunsaturated or unsaturated fatty acids. Typical, non-aqueous gels were modified to contain 1% tamoxifen and three levels of borage oil ( approximately 25% gamma linolenic acid) and the transcutaneous delivery of both tamoxifen and GLA across full thickness skin determined in vitro. Both tamoxifen and gamma linolenic acid permeated the skin with the ratio of moles being consistent at approximately 4:1. This was irrespective of time, amount of borage oil contained in the formulation (above a minimum) and the presence of other (unsaturated) excipients: mineral oil, Miglyiol 810N, white soft paraffin, PEG400 and Cabosil M5. Dose-dependent downfield shifts of tamoxifen aromatic protons were observed in the presence of borage oil and linolenic acid (gamma and alpha), but not saturated triacyl glycerol. The permeation data suggested vehicular complexation between tamoxifen and polyunsaturated constituents of borage oil and that such complexes permeated the skin intact. The 1H NMR data supported the hypothesis that such complexation was a consequence of preferential pi-pi orbital interactions between the phenyl groups of tamoxifen and the multiple double bonds of GLA. The mechanism for the permeation of intact complexes across skin remains to be elucidated. PMID:16115741

  13. New Insights into Hydrogen Bonding and Stacking Interactions in Cellulose

    SciTech Connect

    Langan, Paul

    2011-01-01

    In this quantum chemical study, we explore hydrogen bonding (H-bonding) and stacking interactions in different crystalline cellulose allomorphs, namely cellulose I and cellulose IIII. We consider a model system representing a cellulose crystalline core, made from six cellobiose units arranged in three layers with two chains per layer. We calculate the contributions of intrasheet and intersheet interactions to the structure and stability in both cellulose I and cellulose IIII crystalline cores. Reference structures for this study were generated from molecular dynamics simulations of water-solvated cellulose I and IIII fibrils. A systematic analysis of various conformations describing different mutual orientations of cellobiose units is performed using the hybrid density functional theory (DFT) with the M06-2X with 6-31+G (d, p) basis sets. We dissect the nature of the forces that stabilize the cellulose I and cellulose IIII crystalline cores and quantify the relative strength of H-bonding and stacking interactions. Our calculations demonstrate that individual H-bonding interactions are stronger in cellulose I than in cellulose IIII. We also observe a significant contribution from cooperative stacking interactions to the stabilization of cellulose I . In addition, the theory of atoms-in-molecules (AIM) has been employed to characterize and quantify these intermolecular interactions. AIM analyses highlight the role of nonconventional CH O H-bonding in the cellulose assemblies. Finally, we calculate molecular electrostatic potential maps for the cellulose allomorphs that capture the differences in chemical reactivity of the systems considered in our study.

  14. Scalar resonances in a unitary {pi}{pi} S-wave model for D{sup +} {r_arrow} {pi}{sup+}{pi}{sup-}{pi}{sup+}.

    SciTech Connect

    Boito, D. R.; Dedonder, J.-P.; El-Bennich, B.; Leitner, O.; Loiseau, B.; Physics; Univ. Autonoma de Barcelona; Univ. de Sao Paulo; Univ. Paris; Pl. Jussieu; Lab. Nazionali de Frascati

    2009-02-19

    We propose a model for D{sup +} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup +} decays following experimental results which indicate that the two-pion interaction in the S wave is dominated by the scalar resonances f{sub 0}(600)/{sigma} and f{sub 0}(980). The weak decay amplitude for D{sup +} {yields} R{pi}{sup +}, where R is a resonance that subsequently decays into {pi}{sup +}{pi}{sup -}, is constructed in a factorization approach. In the S wave, we implement the strong decay R {yields} {pi}{sup +}{pi}{sup -} by means of a scalar form factor. This provides a unitary description of the pion-pion interaction in the entire kinematically allowed mass range m{sub {pi}{pi}}{sup 2} from threshold to about 3 GeV{sup 2}. In order to reproduce the experimental Dalitz plot for D{sup +} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup +}, we include contributions beyond the S wave. For the P wave, dominated by the {rho}(770){sup 0}, we use a Breit-Wigner description. Higher waves are accounted for by using the usual isobar prescription for the f{sub 2}(1270) and {rho}(1450){sup 0}. The major achievement is a good reproduction of the experimental m{sub {pi}{pi}}{sup 2} distribution, and of the partial as well as the total D{sup +} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup +} branching ratios. Our values are generally smaller than the experimental ones. We discuss this shortcoming and, as a by-product, we predict a value for the poorly known D {yields} {sigma} transition form factor at q{sup 2} = m{sub {pi}}{sup 2}.

  15. Stacked stem cell sheets enhance cell-matrix interactions

    PubMed Central

    Patel, Nikul G; Zhang, Ge

    2014-01-01

    Cell sheet engineering has enabled the production of confluent cell sheets stacked together for use as a cardiac patch to increase cell survival rate and engraftment after transplantation, thereby providing a promising strategy for high density stem cell delivery for cardiac repair. One key challenge in using cell sheet technology is the difficulty of cell sheet handling due to its weak mechanical properties. A single-layer cell sheet is generally very fragile and tends to break or clump during harvest. Effective transfer and stacking methods are needed to move cell sheet technology into widespread clinical applications. In this study, we developed a simple and effective micropipette based method to aid cell sheet transfer and stacking. The cell viability after transfer was tested and multi-layer stem cell sheets were fabricated using the developed method. Furthermore, we examined the interactions between stacked stem cell sheets and fibrin matrix. Our results have shown that the preserved ECM associated with the detached cell sheet greatly facilitates its adherence to fibrin matrix and enhances the cell sheet-matrix interactions. Accelerated fibrin degradation caused by attached cell sheets was also observed. PMID:24769850

  16. Diffractive Dissociation into {pi}{sup -{pi}-{pi}+} Final States at COMPASS

    SciTech Connect

    Haas, Florian

    2010-08-05

    QCD predicts gluonic excitations like hybrids to contribute to the meson spectrum in addition to qq-bar pair configurations. The most promising way to identify such states is the search for J{sup PC} quantum number combinations which are forbidden in the constituent quark model. The fixed target COMPASS experiment at CERN offers the opportunity to search for such states in the light quark sector with an unprecedented statistics.Diffractive reactions of 190 GeV/c pions on a lead target were studied by COMPASS during a pilot run in 2004. A Partial Wave Analysis (PWA) of the {pi}{sup -{pi}-{pi}+} final state with 42 waves including acceptance corrections through a phase-space Monte Carlo simulation of the spectrometer was performed. The exotic {pi}{sub 1}(1600) meson with quantum numbers J{sup PC} = 1{sup -+} has been clearly established in the rho-pi decay channel with a mass of 1660{+-}10(stat) MeV/c{sup 2} and a width of 269{+-}21(stat) MeV/c{sup 2}. The improved detector performance in 2008 allows us to study this channel with significantly higher statistics. First results of the ongoing analysis of the 2008 data taking period, using a 190 GeV/c pion beam on a liquid hydrogen target are presented in this paper.

  17. Diffractive Dissociation into {pi}{sup -{pi}-{pi}+} Final States at COMPASS

    SciTech Connect

    Haas, Florian

    2011-10-24

    QCD predicts gluonic excitations like hybrids to contribute to the meson spectrum in addition to qq-bar pair configurations. The most promising way to identify such states is the search for J{sup PC} quantum number combinations which are forbidden in the constituent quark model. The fixed target COMPASS experiment at CERN offers the opportunity to search for such states in the light quark sector with an unprecedented statistics.Diffractive reactions of 190 GeV/c pions on a lead target were studied by COMPASS during a pilot run in 2004. A Partial Wave Analysis (PWA) of the {pi}{sup -{pi}-{pi}+} final state with 42 waves including acceptance corrections through a phase-space Monte Carlo simulation of the spectrometer was performed. The exotic {pi}{sup 1}(1600) meson with quantum numbers J{sup PC} = 1{sup -+} has been clearly established in the rho-pi decay channel with a mass of 1660{+-}10(stat) MeV/c{sup 2} and a width of 269{+-}21(stat) MeV/c{sup 2}. The improved detector performance in 2008 allows us to study this channel with significantly higher statistics. First results of the ongoing analysis of the 2008 data taking period, using a 190 GeV/c pion beam on a liquid hydrogen target are presented in this paper.

  18. Atomic-scale details of dislocation - stacking fault tetrahedra interaction.

    SciTech Connect

    Osetskiy, Yury N; Stoller, Roger E; Rodney, David; Bacon, David J

    2005-01-01

    Stacking fault tetrahedra (SFTs) are formed during irradiation of fcc. metals and alloys with low stacking fault energy. The high number density of SFTs observed suggests that they should contribute to radiation-induced hardening and, therefore, be taken into account when estimating mechanical property changes of irradiated materials. The key issue is to describe the interaction between a moving dislocation and an individual SFT, which is characterized by a small physical scale of about 100 nm. In this paper we present results of an atomistic simulation of edge and screw dislocations interacting with small SFTs at different temperatures and strain rates and present mechanisms which can explain the formation of defect-free channels observed experimentally.

  19. Interactive histology of large-scale biomedical image stacks.

    PubMed

    Jeong, Won-Ki; Schneider, Jens; Turney, Stephen G; Faulkner-Jones, Beverly E; Meyer, Dominik; Westermann, Rüdiger; Reid, R Clay; Lichtman, Jeff; Pfister, Hanspeter

    2010-01-01

    Histology is the study of the structure of biological tissue using microscopy techniques. As digital imaging technology advances, high resolution microscopy of large tissue volumes is becoming feasible; however, new interactive tools are needed to explore and analyze the enormous datasets. In this paper we present a visualization framework that specifically targets interactive examination of arbitrarily large image stacks. Our framework is built upon two core techniques: display-aware processing and GPU-accelerated texture compression. With display-aware processing, only the currently visible image tiles are fetched and aligned on-the-fly, reducing memory bandwidth and minimizing the need for time-consuming global pre-processing. Our novel texture compression scheme for GPUs is tailored for quick browsing of image stacks. We evaluate the usability of our viewer for two histology applications: digital pathology and visualization of neural structure at nanoscale-resolution in serial electron micrographs. PMID:20975179

  20. Study of B0 --> J/psiK(*)0pi(+)pi(-) decays with the collider detector at Fermilab.

    PubMed

    Affolder, T; Akimoto, H; Akopian, A; Albrow, M G; Amaral, P; Amidei, D; Anikeev, K; Antos, J; Apollinari, G; Arisawa, T; Artikov, A; Asakawa, T; Ashmanskas, W; Azfar, F; Azzi-Bacchetta, P; Bacchetta, N; Bachacou, H; Bailey, S; de Barbaro, P; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Baroiant, S; Barone, M; Bauer, G; Bedeschi, F; Belforte, S; Bell, W H; Bellettini, G; Bellinger, J; Benjamin, D; Bensinger, J; Beretvas, A; Berge, J P; Berryhill, J; Bhatti, A; Binkley, M; Bisello, D; Bishai, M; Blair, R E; Blocker, C; Bloom, K; Blumenfeld, B; Blusk, S R; Bocci, A; Bodek, A; Bokhari, W; Bolla, G; Bonushkin, Y; Bortoletto, D; Boudreau, J; Brandl, A; van den Brink, S; Bromberg, C; Brozovic, M; Brubaker, E; Bruner, N; Buckley-Geer, E; Budagov, J; Budd, H S; Burkett, K; Busetto, G; Byon-Wagner, A; Byrum, K L; Cabrera, S; Calafiura, P; Campbell, M; Carithers, W; Carlson, J; Carlsmith, D; Caskey, W; Castro, A; Cauz, D; Cerri, A; Chan, A W; Chang, P S; Chang, P T; Chapman, J; Chen, C; Chen, Y C; Cheng, M-T; Chertok, M; Chiarelli, G; Chirikov-Zorin, I; Chlachidze, G; Chlebana, F; Christofek, L; Chu, M L; Chung, Y S; Ciobanu, C I; Clark, A G; Colijn, A P; Connolly, A; Conway, J; Cordelli, M; Cranshaw, J; Cropp, R; Culbertson, R; Dagenhart, D; D'Auria, S; DeJongh, F; Dell'Agnello, S; Dell'Orso, M; Demortier, L; Deninno, M; Derwent, P F; Devlin, T; Dittmann, J R; Dominguez, A; Donati, S; Done, J; D'Onofrio, M; Dorigo, T; Eddy, N; Einsweiler, K; Elias, J E; Engels, E; Erbacher, R; Errede, D; Errede, S; Fan, Q; Fang, H-C; Feild, R G; Fernandez, J P; Ferretti, C; Field, R D; Fiori, I; Flaugher, B; Foster, G W; Franklin, M; Freeman, J; Friedman, J; Fukui, Y; Furic, I; Galeotti, S; Gallas, A; Gallinaro, M; Gao, T; Garcia-Sciveres, M; Garfinkel, A F; Gatti, P; Gay, C; Gerdes, D W; Giannetti, P; Giromini, P; Glagolev, V; Glenzinski, D; Gold, M; Goldstein, J; Gorelov, I; Goshaw, A T; Gotra, Y; Goulianos, K; Green, C; Grim, G; Gris, P; Groer, L; Grosso-Pilcher, C; Guenther, M; Guillian, G; Guimaraes da Costa, J; Haas, R M; Haber, C; Hahn, S R; Hall, C; Handa, T; Handler, R; Hao, W; Happacher, F; Hara, K; Hardman, A D; Harris, R M; Hartmann, F; Hatakeyama, K; Hauser, J; Heinrich, J; Heiss, A; Herndon, M; Hill, C; Hoffman, K D; Holck, C; Hollebeek, R; Holloway, L; Huffman, B T; Hughes, R; Huston, J; Huth, J; Ikeda, H; Incandela, J; Introzzi, G; Iwai, J; Iwata, Y; James, E; Jones, M; Joshi, U; Kambara, H; Kamon, T; Kaneko, T; Karr, K; Kasha, H; Kato, Y; Keaffaber, T A; Kelley, K; Kelly, M; Kennedy, R D; Kephart, R; Khazins, D; Kikuchi, T; Kilminster, B; Kim, B J; Kim, D H; Kim, H S; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kirby, M; Kirk, M; Kirsch, L; Klimenko, S; Koehn, P; Kondo, K; Konigsberg, J; Korn, A; Korytov, A; Kovacs, E; Kroll, J; Kruse, M; Kuhlmann, S E; Kurino, K; Kuwabara, T; Laasanen, A T; Lai, N; Lami, S; Lammel, S; Lancaster, J; Lancaster, M; Lander, R; Lath, A; Latino, G; LeCompte, T; Lee, A M; Lee, K; Leone, S; Lewis, J D; Lindgren, M; Liss, T M; Liu, J B; Liu, Y C; Litvintsev, D O; Lobban, O; Lockyer, N; Loken, J; Loreti, M; Lucchesi, D; Lukens, P; Lusin, S; Lyons, L; Lys, J; Madrak, R; Maeshima, K; Maksimovic, P; Malferrari, L; Mangano, M; Mariotti, M; Martignon, G; Martin, A; Matthews, J A J; Mayer, J; Mazzanti, P; McFarland, K S; McIntyre, P; McKigney, E; Menguzzato, M; Menzione, A; Merkel, P; Mesropian, C; Meyer, A; Miao, T; Miller, R; Miller, J S; Minato, H; Miscetti, S; Mishina, M; Mitselmakher, G; Moggi, N; Moore, E; Moore, R; Morita, Y; Moulik, T; Mulhearn, M; Mukherjee, A; Muller, T; Munar, A; Murat, P; Murgia, S; Nachtman, J; Nagaslaev, V; Nahn, S; Nakada, H; Nakano, I; Nelson, C; Nelson, T; Neu, C; Neuberger, D; Newman-Holmes, C; Ngan, C-Y P; Niu, H; Nodulman, L; Nomerotski, A; Oh, S H; Oh, Y D; Ohmoto, T; Ohsugi, T; Oishi, R; Okusawa, T; Olsen, J; Orejudos, W; Pagliarone, C; Palmonari, F; Paoletti, R; Papadimitriou, V; Partos, D; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Pellett, D; Pescara, L; Phillips, T J; Piacentino, G; Pitts, K T; Pompos, A; Pondrom, L; Pope, G; Popovic, M; Prokoshin, F; Proudfoot, J; Ptohos, F; Pukhov, O; Punzi, G; Rakitine, A; Ratnikov, F; Reher, D; Reichold, A; Ribon, A; Riegler, W; Rimondi, F; Ristori, L; Riveline, M; Robertson, W J; Robinson, A; Rodrigo, T; Rolli, S; Rosenson, L; Roser, R; Rossin, R; Rott, C; Roy, A; Ruiz, A; Safonov, A; St Denis, R; Sakumoto, W K; Saltzberg, D; Sanchez, C; Sansoni, A; Santi, L; Sato, H; Savard, P; Schlabach, P; Schmidt, E E; Schmidt, M P; Schmitt, M; Scodellaro, L; Scott, A; Scribano, A; Segler, S; Seidel, S; Seiya, Y; Semenov, A; Semeria, F; Shah, T; Shapiro, M D; Shepard, P F; Shibayama, T; Shimojima, M; Shochet, M; Sidoti, A; Siegrist, J; Sill, A; Sinervo, P; Singh, P; Slaughter, A J; Sliwa, K; Smith, C; Snider, F D; Solodsky, A; Spalding, J; Speer, T; Sphicas, P; Spinella, F; Spiropulu, M; Spiegel, L; Steele, J; Stefanini, A; Strologas, J

    2002-02-18

    We report a study of the decays B0 --> J/psiK(*)0pi(+)pi(-), which involve the creation of a uu or dd quark pair in addition to a b -->c(cs) decay. The data sample consists of 110 pb(-1) of pp collisions at square root[s] = 1.8 TeV collected by the CDF detector at the Fermilab Tevatron collider during 1992-1995. We measure the branching fractions to be B(B0 --> J/psiK(*0)pi(+)pi(-)) = (6.6 +/- 1.9 +/- 1.1)x10(-4) and B(B0 --> J/psiK0pi(+)pi(-)) = (10.3 +/- 3.3 +/- 1.5)x10(-4). Evidence is seen for contributions from psi(2S)K(*)0, J/psiK0rho(0), J/psiK(*+)pi(-), and J/psiK1(1270). PMID:11863882

  1. Search for resonances decaying to etac pi pi- in two-photon interactions

    SciTech Connect

    Lees, J.P.; Poireau, V.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Palano, A.; Eigen, G.; Stugu, B.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Koch, H.; Schroeder, T.; Asgeirsson, D.J.; Hearty, C.; Mattison, T.S.; McKenna, J.A.; So, R.Y.; Khan, A.; Blinov, V.E.; /more authors..

    2012-06-18

    We report a study of the process {gamma}{gamma} {yields} X {yields} {eta}{sub c}{pi}{sup +}{pi}{sup -}, where X stands for one of the resonances {chi}{sub c2}(1P), {eta}{sub c}(2S), X(3872), X(3915), or {chi}{sub c2}(2P). The analysis is performed with a data sample of 473.9 fb{sup -1} collected with the BABAR detector at the PEP-II asymmetric-energy electron-positron collider. We do not observe a significant signal for any channel, and calculate 90% confidence-level upper limits on the products of branching fractions and two-photon widths {Lambda}{sub X{yields}{gamma}{gamma}} {Beta}(X {yields} {eta}{sub c}{pi}{sup +}{pi}{sup -}): 15.7 eV for {chi}{sub c2}(1P), 133 eV for {eta}{sub c}(2S), 11.1 eV for X(3872) (assuming it to be a spin-2 state), 16 eV for X(3915) (assuming it to be a spin-2 state), and 19 eV for {chi}{sub c2}(2P). We also report upper limits on the ratios of branching fractions {Beta}({eta}{sub c}(2S) {yields} {eta}{sub c}{pi}{sup +}{pi}{sup -})/{Beta}({eta}{sub c}(2S) {yields} K{sub S}{sup 0}K{sup +}{pi}{sup -}) < 10.0 and {Beta}({chi}{sub c2}(1P) {yields} {eta}{sub c}{pi}{sup +}{pi}{sup -})/{Beta}({chi}{sub c2}(1P) {yields} K{sub S}{sup 0}K{sup +}{pi}{sup -}) < 32.9 at the 90% confidence level.

  2. Measurement of CP Asymmetries and Branching Fractions in B0 -> pi+ pi-, B0 -> K+ pi-, B0 -> pi0 pi0, B0 -> K0 pi0 and Isospin Analysis of B -> pi pi Decays

    SciTech Connect

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

    2008-08-01

    The authors present preliminary results of improved measurements of the CP-violating asymmetries and branching fractions in the decays B{sup 0} {yields} {pi}{sup +}{pi}{sup -}, B{sup 0} {yields} K{sup +}{pi}{sup -}, B{sup 0} {yields} {pi}{sup 0}{pi}{sup 0}, and B{sup 0} {yields} K{sup 0}{pi}{sup 0}. This update includes all data taken at the {Upsilon}(4S) resonance by the BABAR experiment at the asymmetric PEP-II B-meson factory at SLAC, corresponding to 467 {+-} 5 million B{bar B} pairs. They find S{sub {pi}{pi}} = -0.68 {+-} 0.10 {+-} 0.03, C{sub {pi}{pi}} = -0.25 {+-} 0.08 {+-} 0.02, {Alpha}{sub K{sub {pi}}} = -0.107 {+-} 0.016{sub -0.004},{sup +0.006}, C{sub {pi}{sup 0}{pi}{sup 0}} = -0.43 {+-} 0.26 {+-} 0.05, {Beta}(B{sup 0} {yields} {pi}{sup 0}{pi}{sup 0}) = (1.83 {+-} 0.21 {+-} 0.13) x 10{sup -6}, {Beta}(B{sup 0} {yields} K{sup 0}{pi}{sup 0}) = (10.1 {+-} 0.6 {+-} 0.4) x 10{sup -6}, where the first error is statistical and the second is systematic. They observe CP violation with a significance of 6.7{sigma} in B{sup 0} {yields} {pi}{sup -} and 6.1{sigma} in B{sup 0} {yields} K{sup +}{pi}{sup -}. Constraints on the Unitarity Triangle angle {alpha} are determined from the isospin relation between all B {yields} {pi}{pi} rates and asymmetries.

  3. Modulating the Light Switch by [superscript 3]MLCT-[superscript 3]pi pi* State Interconversion

    SciTech Connect

    Spencer, Brigitte R.; Kraft, Brian J.; Hughes, Chris G.; Pink, Maren; Zaleski, Jeffrey M.

    2012-01-20

    intercalation (K{sub b} = 3.3 x 10{sup 4} M{sup -1}). The origin of this light switch behavior involves two competing {sup 3}MLCT states similar to that of the extensively studied light switch molecule [Ru(phen){sub 2}dppz]{sup 2+}. The solvent- and temperature-dependence of the luminescence of 3 reveal that the extended ligand aromaticity lowers the energy of the {sup 3}{pi}{pi}* excited state into competition with the emitting {sup 3}MLCT state. Interconversion between these two states plays a significant role in the observed photophysics and is responsible for the dual emission in aqueous environments.

  4. RKKY interaction in AB-stacked multilayer graphene

    NASA Astrophysics Data System (ADS)

    Jiang, Liwei; Lü, Xiaoling; Gao, Wenzhu; Yu, Guodong; Liu, Zhe; Zheng, Yisong

    2012-05-01

    The RKKY interaction between two magnetic impurities absorbed on the surface layer of half-filled AB-stacked multilayer graphene (ABSMLG) is theoretically studied based on the lattice Green’s function technique. In comparison with the case of monolayer graphene, the RKKY interaction in such multilayer graphene presents distinct properties in some aspects. Firstly, from the numerical results, we find that the thickness of the ABSMLG influences the RKKY interaction in a complicated manner, depending on the odd/even parity of the number of layers and the sublattice attribution of the positions of the two magnetic impurities. Then, we derive the asymptotic expressions of the RKKY interactions in ABSMLG in the long-distance limit. For even-layered ABSMLG, we find that the RKKY interactions of the 1A-1A, 1B-1A and 1B-1B couplings fall off as 1/R2, 1/R4 and 1/R6 (1A and 1B stand for, respectively, the sublattice points in the surface layer, which are positioned directly on the plaquette and on a lattice point of the layer underneath). On the other hand, in odd-layered ABSMLG, the decays of these interactions follow the 1/R2, 1/R3 and 1/R3 power laws respectively. In addition, we also find that these analytical expressions are quantitatively valid to describe the RKKY interaction in ABSMLG when the distance between the two magnetic impurities is larger than the lattice constant of graphene by one order of magnitude.

  5. Study of the D0 ---> pi- pi+ pi- pi+ decay

    SciTech Connect

    Link, J.M.; Yager, P.M.; Anjos, J.C.; Bediaga, I.; Castromonte, C.; Machado, A.A.; Magnin, J.; Massafferri, A.; de Miranda, J.M.; Pepe, I.M.; Polycarpo, E.; /Rio de Janeiro, CBPF /CINVESTAV, IPN /Colorado U. /Fermilab /Frascati /Guanajuato U. /Illinois U., Urbana /Indiana U. /Korea U. /Kyungpook Natl. U. /INFN, Milan /Milan U.

    2007-01-01

    Using data from the FOCUS (E831) experiment at Fermilab, they present new measurements for the Cabbibo-suppressed decay mode D{sup 0} {yields} {pi}{sup -}{pi}{sup +}{pi}{sup -}{pi}{sup +}. They measure the branching ratio {Lambda}(D{sup 0} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -})/{Lambda}(D{sup 0} {yields} K{sup -} {pi}{sup +}{pi}{sup -}{pi}{sup +}) = 0.0914 {+-} 0.0018 {+-} 0.0022. An amplitude analysis has been performed, a first for this channel, in order to determine the resonant substructure of this decay mode. The dominant component is the decay D{sup 0} {yields} a{sub 1}(1260){sup +}{pi}{sup -}, accounting for 60% of the decay rate. The second most dominant contribution comes from the decay D{sup 0} {yields} {rho}(770){sup 0}{rho}(770){sup 0}, with a fraction of 25%. They also study the a{sub 1}(1260) line shape and resonant substructure. Using the helicity formalism for the angular distribution of the decay D{sup 0} {yields} {rho}(770){sup 0}{rho}(770){sup 0}, they measure a longitudinal polarization of P{sub L} = (71 {+-} 4 {+-} 2)%.

  6. Search for D0-D0 mixing and branching-ratio measurement in the decay D0-->K+ pi- pi0.

    PubMed

    Aubert, B; Barate, R; Bona, M; Boutigny, D; Couderc, F; Karyotakis, Y; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Grauges, E; Palano, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Gill, M S; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; Del Amo Sanchez, P; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schroeder, T; Steinke, M; Boyd, J T; Burke, J P; Cottingham, W N; Walker, D; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Kyberd, P; Saleem, M; Sherwood, D J; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Best, D S; Bondioli, M; Bruinsma, M; Chao, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Zhang, L; Hadavand, H K; Hill, E J; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dvoretskii, A; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Ruddick, W O; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Chen, A; Eckhart, E A; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Zeng, Q; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Petzold, A; Spaan, B; Brandt, T; Klose, V; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Grenier, P; Latour, E; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Flack, R L; Nash, J A; Nikolich, M B; Panduro Vazquez, W; Behera, P K; Chai, X; Charles, M J; Mallik, U; Meyer, N T; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gritsan, A V; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Davier, M; Grosdidier, G; Höcker, A; Le Diberder, F; Lepeltier, V; Lutz, A M; Oyanguren, A; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Stocchi, A; Wang, W F; Wormser, G; Cheng, C H; Lange, D J; Wright, D M; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; George, K A; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; Di Lodovico, F; Menges, W; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; Naisbit, M T; Williams, J C; Yi, J I; Chen, C; Hulsbergen, W D; Jawahery, A; Lae, C K; Roberts, D A; Simi, G; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Saremi, S; Staengle, H; Cowan, R; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Kim, H; McLachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Raven, G; Snoek, H L; Jessop, C P; Losecco, J M; Allmendinger, T; Benelli, G; Gan, K K; Honscheid, K; Hufnagel, D; Jackson, P D; Kagan, H; Kass, R; Rahimi, A M; Ter-Antonyan, R; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; Chauveau, J; Briand, H; David, P

    2006-12-01

    We analyze 230.4 fb;{-1} of data collected with the BABAR detector at the PEP-II e;{+}e;{-} collider at SLAC to search for evidence of D0-D[over ];{0} mixing using regions of phase space in the decay D;{0}-->K;{+}pi;{-}pi;{0}. We measure the time-integrated mixing rate R_{M}=(0.023_{-0.014};{+0.018}(stat.)+/-0.004(syst.))%, and R_{M}<0.054% at the 95% confidence level, assuming CP invariance. The data are consistent with no mixing at the 4.5% confidence level. We also measure the branching ratio for D;{0}-->K;{+}pi;{-}pi;{0} relative to D;{0}-->K;{-}pi;{+}pi;{0} to be (0.214+/-0.008(stat.)+/-0.008(syst.))%. PMID:17155794

  7. Observation of a broad structure in the pi+ pi- J/psi mass spectrum around 4.26 GeV/c2.

    PubMed

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

    2005-09-30

    We study initial-state radiation events, e+ e- --> gammaISR pi+ pi- J/psi, with data collected with the BABAR detector. We observe an accumulation of events near 4.26 GeV/c2 in the invariant-mass spectrum of pi+ pi- J/psi. Fits to the mass spectrum indicate that a broad resonance with a mass of about 4.26 GeV/c2 is required to describe the observed structure. The presence of additional narrow resonances cannot be excluded. The fitted width of the broad resonance is 50 to 90 MeV/c2, depending on the fit hypothesis. PMID:16241645

  8. Search for CP Violation in the Decays D0 to K- K+and D0 to pi- pi+

    SciTech Connect

    Aubert, B.; Bona, M.; Boutigny, D.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prudent, X.; Tisserand, V.; Zghiche, A.; Garra Tico, J.; Grauges, E.; Lopez, L.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Abrams, G.S.; Battaglia, M.; Brown, D.N.; Button-Shafer, J.; /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Karlsruhe U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /Pisa U. /Pisa, Scuola Normale Superiore /INFN, Pisa /Princeton U. /Rome U. /INFN, Rome /Rostock U. /Rutherford /DSM, DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison /Yale U.

    2007-09-24

    We measure CP-violating asymmetries of neutral charmed mesons in the modes D{sup 0} {yields} K{sup -}K{sup +} and D{sup 0} {yields} {pi}{sup -}{pi}{sup +} with the highest precision to date by using D{sup 0} {yields} K{sup -}{pi}{sup +} decays to correct detector asymmetries. An analysis of 385.8 fb{sup -}1 of data collected with the BaBar detector yields values of a{sup KK}{sub CP} = (0.00 {+-} 0.34 (stat.) {+-} 0.13 (syst.))% and a{sup {pi}{pi}}{sub CP} = (-0.24 {+-} 0.52 (stat.) {+-} 0.22 (syst.))%, which agree with Standard Model predictions.

  9. A breathing wormlike chain model on DNA denaturation and bubble: effects of stacking interactions.

    PubMed

    Kim, Jae-Yeol; Jeon, Jae-Hyung; Sung, Wokyung

    2008-02-01

    DNA stably exists as a double-stranded structure due to hydrogen-bonding and stacking interactions between bases. The stacking interactions are strengthened when DNA is paired, which results in great enhancement of bending rigidity. We study the effects of this stacking-induced stiffness difference on DNA denaturation and bubble formations. To this end, we model double-stranded DNA as a duplex of two semiflexible chains whose persistence length varies depending on the base-pair distance. Using this model, we perform the Langevin dynamics simulation to examine the characteristics of the denaturation transition and the statistics of the bubbles. We find that the inclusion of the stacking interactions causes the denaturation transition to be much sharper than otherwise. At physiological temperature, the stacking interactions prohibit the initiation of bubble formation but promote bubbles, once grown, to retain the large size. PMID:18266461

  10. Measurement of partial widths and search for direct CP violation in D0 meson decays to K-K+ and pi-pi+.

    PubMed

    Acosta, D; Affolder, T; Akimoto, T; Albrow, M G; Ambrose, D; Amerio, S; Amidei, D; Anastassov, A; Anikeev, K; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Arisawa, T; Arguin, J-F; Artikov, A; Ashmanskas, W; Attal, A; Azfar, F; Azzi-Bacchetta, P; Bacchetta, N; Bachacou, H; Badgett, W; Barbaro-Galtieri, A; Barker, G J; Barnes, V E; Barnett, B A; Baroiant, S; Barone, M; Bauer, G; Bedeschi, F; Behari, S; Belforte, S; Bellettini, G; Bellinger, J; Benjamin, D; Beretvas, A; Bhatti, A; Binkley, M; Bisello, D; Bishai, M; Blair, R E; Blocker, C; Bloom, K; Blumenfeld, B; Bocci, A; Bodek, A; Bolla, G; Bolshov, A; Booth, P S L; Bortoletto, D; Boudreau, J; Bourov, S; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Burkett, K; Busetto, G; Bussey, P; Byrum, K L; Cabrera, S; Calafiura, P; Campanelli, M; Campbell, M; Canepa, A; Casarsa, M; Carlsmith, D; Carron, S; Carosi, R; Cavalli-Sforza, M; Castro, A; Catastini, P; Cauz, D; Cerri, A; Cerri, C; Cerrito, L; Chapman, J; Chen, C; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, I; Cho, K; Chokheli, D; Chu, M L; Chuang, S; Chung, J Y; Chung, W-H; Chung, Y S; Ciobanu, C I; Ciocci, M A; Clark, A G; Clark, D; Coca, M; Connolly, A; Convery, M; Conway, J; Cooper, B; Cordelli, M; Cortiana, G; Cranshaw, J; Cuevas, J; Culbertson, R; Currat, C; Cyr, D; Dagenhart, D; Da Ronco, S; D'Auria, S; de Barbaro, P; De Cecco, S; De Lentdecker, G; Dell'agnello, S; Dell'orso, M; Demers, S; Demortier, L; Deninno, M; De Pedis, D; Derwent, P F; Dionisi, C; Dittmann, J R; Doksus, P; Dominguez, A; Donati, S; Donega, M; Donini, J; D'Onofrio, M; Dorigo, T; Drollinger, V; Ebina, K; Eddy, N; Ely, R; Erbacher, R; Erdmann, M; Errede, D; Errede, S; Eusebi, R; Fang, H-C; Farrington, S; Fedorko, I; Feild, R G; Feindt, M; Fernandez, J P; Ferretti, C; Field, R D; Fiori, I; Flanagan, G; Flaugher, B; Flores-Castillo, L R; Foland, A; Forrester, S; Foster, G W; Franklin, M; Freeman, J; Frisch, H; Fujii, Y; Furic, I; Gajjar, A; Gallas, A; Galyardt, J; Gallinaro, M; Garcia-Sciveres, M; Garfinkel, A F; Gay, C; Gerberich, H; Gerdes, D W; Gerchtein, E; Giagu, S; Giannetti, P; Gibson, A; Gibson, K; Ginsburg, C; Giolo, K; Giordani, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Goldstein, D; Goldstein, J; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Gotra, Y; Goulianos, K; Gresele, A; Griffiths, M; Grosso-Pilcher, C; Guenther, M; Guimaraes da Costa, J; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Handler, R; Happacher, F; Hara, K; Hare, M; Harr, R F; Harris, R M; Hartmann, F; Hatakeyama, K; Hauser, J; Hays, C; Hayward, H; Heider, E; Heinemann, B; Heinrich, J; Hennecke, M; Herndon, M; Hill, C; Hirschbuehl, D; Hocker, A; Hoffman, K D; Holloway, A; Hou, S; Houlden, M A; Huffman, B T; Huang, Y; Hughes, R E; Huston, J; Ikado, K; Incandela, J; Introzzi, G; Iori, M; Ishizawa, Y; Issever, C; Ivanov, A; Iwata, Y; Iyutin, B; James, E; Jang, D; Jarrell, J; Jeans, D; Jensen, H; Jeon, E J; Jones, M; Joo, K K; Jun, S; Junk, T; Kamon, T; Kang, J; Karagoz Unel, M; Karchin, P E; Kartal, S; Kato, Y; Kemp, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, M S; Kim, S B; Kim, S H; Kim, T H; Kim, Y K; King, B T; Kirby, M; Kirsch, L; Klimenko, S; Knuteson, B; Ko, B R; Kobayashi, H; Koehn, P; Kong, D J; Kondo, K; Konigsberg, J; Kordas, K; Korn, A; Korytov, A; Kotelnikov, K; Kotwal, A V; Kovalev, A; Kraus, J; Kravchenko, I; Kreymer, A; Kroll, J; Kruse, M; Krutelyov, V; Kuhlmann, S E; Kuznetsova, N; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, J; Lancaster, M; Lander, R; Lannon, K; Lath, A; Latino, G; Lauhakangas, R; Lazzizzera, I; Le, Y; Lecci, C; Lecompte, T; Lee, J; Lee, J; Lee, S W; Leonardo, N; Leone, S; Lewis, J D; Li, K; Lin, C; Lin, C S; Lindgren, M; Liss, T M; Litvintsev, D O; Liu, T; Liu, Y; Lockyer, N S; Loginov, A; Loreti, M; Loverre, P; Lu, R-S; Lucchesi, D; Lujan, P; Lukens, P; Lyons, L; Lys, J; Lysak, R; Macqueen, D; Madrak, R; Maeshima, K; Maksimovic, P; Malferrari, L; Manca, G; Marginean, R; Martin, M; Martin, A; Martin, V; Martínez, M; Maruyama, T; Matsunaga, H; Mattson, M; Mazzanti, P; McFarland, K S; McGivern, D; McIntyre, P M; McNamara, P; Ncnulty, R; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; Miao, T; Miladinovic, N; Miller, L; Miller, R; Miller, J S; Miquel, R; Miscetti, S; Mitselmakher, G; Miyamoto, A; Miyazaki, Y; Moggi, N; Mohr, B; Moore, R; Morello, M; Mukherjee, A; Mulhearn, M; Muller, T; Mumford, R; Munar, A; Murat, P; Nachtman, J; Nahn, S; Nakamura, I; Nakano, I; Napier, A; Napora, R; Naumov, D; Necula, V; Niell, F; Nielsen, J; Nelson, C; Nelson, T; Neu, C; Neubauer, M S; Newman-Holmes, C; Nicollerat, A-S; Nigmanov, T; Nodulman, L; Norniella, O; Oesterberg, K; Ogawa, T; Oh, S H; Oh, Y D; Ohsugi, T; Okusawa, T; Oldeman, R; Orava, R; Orejudos, W; Pagliarone, C; Palmonari, F; Paoletti, R; Papadimitriou, V; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Pauly, T; Paus, C; Pellett, D; Penzo, A; Phillips, T J; Piacentino, G; Piedra, J; Pitts, K T; Plager, C; Pompos, A; Pondrom, L; Pope, G; Poukhov, O; Prakoshyn, F; Pratt, T; Pronko, A; Proudfoot, J; Ptohos, F; Punzi, G; Rademacker, J; Rakitine, A; Rappoccio, S; Ratnikov, F; Ray, H; Reichold, A; Reisert, B; Rekovic, V; Renton, P; Rescigno, M; Rimondi, F; Rinnert, K; Ristori, L; Robertson, W J; Robson, A; Rodrigo, T; Rolli, S; Rosenson, L; Roser, R; Rossin, R; Rott, C; Russ, J; Ruiz, A; Ryan, D; Saarikko, H; Safonov, A; St Denis, R; Sakumoto, W K; Salamanna, G; Saltzberg, D; Sanchez, C; Sansoni, A; Santi, L; Sarkar, S; Sato, K; Savard, P; Savoy-Navarro, A; Schemitz, P; Schlabach, P; Schmidt, E E; Schmidt, M P; Schmitt, M; Scodellaro, L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semeria, F; Sexton-Kennedy, L; Sfiligoi, I; Shapiro, M D; Shears, T; Shepard, P F; Shimojima, M; Shochet, M; Shon, Y; Shreyber, I; Sidoti, A; Siegrist, J; Siket, M; Sill, A; Sinervo, P; Sisakyan, A; Skiba, A; Slaughter, A J; Sliwa, K; Smirnov, D; Smith, J R; Snider, F D; Snihur, R; Somalwar, S V; Spalding, J; Spezziga, M; Spiegel, L; Spinella, F; Spiropulu, M; Squillacioti, P; Stadie, H; Stefanini, A; Stelzer, B; Stelzer-Chilton, O; Strologas, J; Stuart, D; Sukhanov, A; Sumorok, K; Sun, H; Suzuki, T; Taffard, A; Tafirout, R; Takach, S F; Takano, H; Takashima, R; Takeuchi, Y; Takikawa, K; Tanaka, M; Tanaka, R; Tanimoto, N; Tapprogge, S; Tecchio, M; Teng, P K; Terashi, K; Tesarek, R J; Tether, S; Thom, J; Thompson, A S; Thomson, E; Tipton, P; Tiwari, V; Tkaczyk, S; Toback, D; Tollefson, K; Tomura, T; Tonelli, D; Tönnesmann, M; Torre, S; Torretta, D; Trischuk, W; Tseng, J; Tsuchiya, R; Tsuno, S; Tsybychev, D; Turini, N; Turner, M; Ukegawa, F; Unverhau, T; Uozumi, S; Usynin, D; Vacavant, L; Vaiciulis, A; Varganov, A; Vataga, E; Vejcik, S; Velev, G; Veramendi, G; Vickey, T; Vidal, R; Vila, I; Vilar, R; Volobouev, I; von der Mey, M; Wagner, P; Wagner, R G; Wagner, R L; Wagner, W; Wallny, R; Walter, T; Yamashita, T; Yamamoto, K; Wan, Z; Wang, M J; Wang, S M; Warburton, A; Ward, B; Waschke, S; Waters, D; Watts, T; Weber, M; Wester, W C; Whitehouse, B; Wicklund, A B; Wicklund, E; Williams, H H; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolter, M; Worcester, M; Worm, S; Wright, T; Wu, X; Würthwein, F; Wyatt, A; Yagil, A; Yang, U K; Yao, W; Yeh, G P; Yi, K; Yoh, J; Yoon, P; Yorita, K; Yoshida, T; Yu, I; Yu, S; Yu, Z; Yun, J C; Zanello, L; Zanetti, A; Zaw, I; Zetti, F; Zhou, J; Zsenei, A; Zucchelli, S

    2005-04-01

    We present a measurement of relative partial widths and decay rate CP asymmetries in K-K+ and pi(-)pi(+) decays of D0 mesons produced in pp collisions at sqrt[s]=1.96 TeV. We use a sample of 2x10(5) D(*+)-->D0pi(+) (and charge conjugate) decays with the D0 decaying to K-pi(+), K-K+, and pi(-)pi(+), corresponding to 123 pb(-1) of data collected by the Collider Detector at Fermilab II experiment at the Fermilab Tevatron collider. No significant direct CP violation is observed. We measure Gamma(D0-->K-K+)/Gamma(D0-->K-pi(+))=0.0992+/-0.0011+/-0.0012, Gamma(D0-->pi(-)pi(+))/Gamma(D0-->K-pi(+))=0.035 94+/-0.000 54+/-0.000 40, A(CP)(K-K+)=(2.0+/-1.2+/-0.6)%, and A(CP)(pi(-)pi(+))=(1.0+/-1.3+/-0.6)%, where, in all cases, the first uncertainty is statistical and the second is systematic. PMID:15903906

  11. Structure and intermolecular interactions of glipizide from laboratory X-ray powder diffraction.

    PubMed

    Burley, Jonathan C

    2005-12-01

    The crystal structure of glipizide, used as a major treatment of type-2 diabetes, has been determined ab initio using variable-temperature laboratory X-ray powder diffraction combined with a direct-space Monte Carlo/simulated annealing methodology. The strengths of the intermolecular interactions (van der Waals, pi-pi stacking, hydrogen bonding and steric interlock) were quantitatively estimated using the thermal expansion data, which were collected in the same set of experiments as those used to determine the structure. PMID:16306678

  12. Relative substituent position on the strength of π-π stacking interactions

    PubMed Central

    Emenike, Bright U.; Alverez, Celeste N.; Rakovan, John; Kirschbaum, Kristin; Jain, Nirbhay

    2010-01-01

    It was observed that the relative position of the arene substituents have a profound influence on the strength of π-π stacking in the 9-benzyl substituted triptycene system. A new series of model compounds (3a-i) capable of revealing quantitatively π-π stacking interactions was studied. This series of compounds (3a-i) has an ortho substituted methyl group in one of the two interacting arenes and the syn/anti ratios were determined and compared to a series previously studied compounds (4a-i) that have a para methyl group on the corresponding arene. A greater than 50% increase in the strength of π-π stacking interactions was observed with the methyl group in the ortho position comparing to that in the para position. No difference in π-π stacking interactions was observed when the other aromatic ring was a pentafluorobenzoate group. PMID:20209117

  13. Stacking Interactions between 9-Methyladenine and Heterocycles Commonly Found in Pharmaceuticals.

    PubMed

    An, Yi; Doney, Analise C; Andrade, Rodrigo B; Wheeler, Steven E

    2016-05-23

    Complexes of 9-methyladenine with 46 heterocycles commonly found in drugs were located using dispersion-corrected density functional theory, providing a representative set of 408 unique stacked dimers. The predicted binding enthalpies for each heterocycle span a broad range, highlighting the strong dependence of heterocycle stacking interactions on the relative orientation of the interacting rings. Overall, the presence of NH and carbonyl groups lead to the strongest stacking interactions with 9-methyadenine, and the strength of π-stacking interactions is sensitive to the distribution of heteroatoms within the ring as well as the specific tautomer considered. Although molecular dipole moments provide a sound predictor of the strengths and orientations of the 28 monocyclic heterocycles considered, dipole moments for the larger fused heterocycles show very little correlation with the predicted binding enthalpies. PMID:27074615

  14. Experimental and theoretical insights in the alkene-arene intramolecular π-stacking interaction.

    PubMed

    Corne, Valeria; Sarotti, Ariel M; Ramirez de Arellano, Carmen; Spanevello, Rolando A; Suárez, Alejandra G

    2016-01-01

    Chiral acrylic esters derived from biomass were developed as models to have a better insight in the aryl-vinyl π-stacking interactions. Quantum chemical calculations, NMR studies and experimental evidences demonstrated the presence of equilibriums of at least four different conformations: π-stacked and face-to-edge, each of them in an s-cis/s-trans conformation. The results show that the stabilization produced by the π-π interaction makes the π-stacked conformation predominant in solution and this stabilization is slightly affected by the electron density of the aromatic counterpart. PMID:27559414

  15. Experimental and theoretical insights in the alkene–arene intramolecular π-stacking interaction

    PubMed Central

    Corne, Valeria; Sarotti, Ariel M; Ramirez de Arellano, Carmen; Spanevello, Rolando A

    2016-01-01

    Summary Chiral acrylic esters derived from biomass were developed as models to have a better insight in the aryl–vinyl π-stacking interactions. Quantum chemical calculations, NMR studies and experimental evidences demonstrated the presence of equilibriums of at least four different conformations: π-stacked and face-to-edge, each of them in an s-cis/s-trans conformation. The results show that the stabilization produced by the π–π interaction makes the π-stacked conformation predominant in solution and this stabilization is slightly affected by the electron density of the aromatic counterpart. PMID:27559414

  16. Effect of Z Prime -mediated flavor-changing neutral current on B {yields} {pi}{pi} decays

    SciTech Connect

    Sahoo, S.; Das, C. K.; Maharana, L.

    2011-07-15

    We study the effect of Z Prime -mediated flavor-changing neutral current on the B {yields} {pi}{pi} decays. The branching ratios of these decays can be enhanced remarkably in the nonuniversal Z Prime model. Our estimated branching ratios B(B{sup 0} {yields} {pi}{sup 0}{pi}{sup 0}) are enhanced significantly from their standard model (SM) value. For g Prime /g = 1, the branching ratios B(B{sup 0} {yields} {pi}{sup 0}{pi}{sup 0}) are very close to the recently observed experimental values and for higher values of g Prime /g branching ratios are more. Our calculated branching ratios B(B{sup 0} {yields} {pi}{sup +}{pi}{sup -}) and B(B{sup +} {yields} {pi}{sup +}{pi}{sup 0}) are also enhanced from the SM value as well as the recently observed experimental values. These enhancements of branching ratios from their SM value give the possibility of new physics.

  17. A theoretical study of π-stacking interactions in C-substituted tetrazoles.

    PubMed

    Farrokhzadeh, Abdolkarim; Modarresi-Alam, Ali Reza; Akher, Farideh Badichi; Ebrahimi, Ali

    2016-06-01

    The π-stacking effects of benzene ring (Ben) with 1H- and 2H-tetrazole derivatives (1H-TZ-X and 2H-TZ-X) substituted at C5 (where X is Cl, COH, NO, NO2, CN, NH2, OH, OCH3, SH and H) has been investigated by the quantum mechanical calculations at the M06-2X/6-311++G** level. The results indicate the 1H-TZ-X||Ben complexes (|| donates π-stacking interaction) are more stable than 2H-TZ-X||Ben while in unstacked forms, 1H-TZ-X is less stable than 2H-TZ-X. All substituents enhance the π-stacking interaction relative to the unsubstituted ones and enhancement is higher for the electron-withdrawing substituents (EWSs). Also, investigation of the local and direct effect of substituents in stacking interaction showed that all substituents regardless of whether are electron donating or electron withdrawing have an additive effect in π-stacking interaction. Excellent correlations were found between the binding energies of the complexes and combination of substituent constant terms. The results showed that the electrostatic interaction alone is not responsible for stacking stabilization but charge penetration is important. Furthermore, analysis of aromaticity, AIM, ESP and NPA were investigated to obtain aromaticity index, non-bonding interactions, chemical reactivity and polarity (dipole moment), respectively. PMID:27258189

  18. Pi-stacked interactions in explosive crystals: buffers against external mechanical stimuli.

    PubMed

    Zhang, Chaoyang; Wang, Xiaochuan; Huang, Hui

    2008-07-01

    The pi-stacked interactions in some explosive crystal packing are discussed. Taking a typical pi-stacked explosive 2,4,6-trinitrobenzene-1,3,5-triamine (TATB) as a sample and using molecular simulations, we investigated the nature of the pi-stacked interactions versus the external mechanical stimuli causing possible slide and compression of explosives. As a result, between the neighbor layers in the TATB unit cell, the electrostatic attraction decreases with a little decrease of vdW attraction when its top layer slides, whereas the vdW attraction increases with a decrease of electrostatic attraction when TATB crystal is compressed along its c axis. Meanwhile, we studied the correlation between the pi-stacked structures and the impact sensitivities of explosives by means of three representatives including TATB with typical planar pi-stacked structures, 2,2-dinitroethylene-1,1-diamine (Fox-7) with wavelike pi-stacked structures, and 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX) without pi-stacked structure. The results showed that pi-stacked structures, particularly planar layers, can effectively buffer against external mechanical stimuli. That is, pi-stacked structures can partly convert the mechanical energy acting on them into their intermolecular interaction energy, to avoid the increase of the molecular vibration resulting in the explosive decomposition, the formation of hot spots, and the final detonation. This is another reason for the low mechanical sensitivity of pi-stacked explosives besides their stable conjugated molecular structures. PMID:18529058

  19. Model-independent constraints on the weak phase {alpha} (or {phi}{sub 2}) and QCD penguin pollution in B{yields}{pi}{pi} decays

    SciTech Connect

    Xing Zhizhong; Zhang He

    2005-03-01

    We present an algebraic isospin approach towards a more straightforward and model-independent determination of the weak phase {alpha} (or {phi}{sub 2}) and QCD penguin pollution in B{yields}{pi}{pi} decays. The world averages of current experimental data allow us to impose some useful constraints on the isospin parameters of B{yields}{pi}{pi} transitions. We find that the magnitude of {alpha} (or {phi}{sub 2}) extracted from the indirect CP violation in the {pi}{sup +}{pi}{sup -} mode is in agreement with the standard-model expectation from other indirect measurements, but its fourfold discrete ambiguity has to be resolved in the near future.

  20. Scalar mesons in the decays {eta}' {sup {yields}}3{pi}{sup 0} and {eta}' {sup {yields} {pi}0{pi}+{pi}-}

    SciTech Connect

    Likhoded, A. K. Luchinsky, A. V. Samoylenko, V. D.

    2010-10-15

    The decays {eta} {sup {yields}}3{pi}{sup 0} and {eta} {sup {yields} {pi}0{pi}+{pi}-} are considered within the isobar model. It is shown that, in order to explain the branching ratio and the shape of the Dalitz plot for the decay {eta}' {sup {yields}}3{pi}{sup 0}, it is sufficient to take into account the contributions of the {sigma} and a{sub 0} mesons. The inclusion of the {sigma} meson is necessary for reproducing the shape of the distribution over the Dalitz plot. The branching ratio for the decay {eta}' {sup {yields} {pi}0{pi}+{pi}-} is obtained. The predictions for the distributions over the Dalitz plot for this decay are presented. These predictions depend strongly on model parameters.

  1. Pi-Pi complexation of bupivacaine and analogues with aromatic receptors: Implications for overdose remediation

    PubMed Central

    Powell, Evon; Lee, Y-H; Partch, Richard; Dennis, Donn; Morey, Timothy; Varshney, Manoj

    2007-01-01

    The interaction of the important but often overdosed local anesthetic bupivacaine, its structural analogs 2,6-dimethylaniline, and N-methyl-2,6-dimethylacetanilide, and cocaine, with several electron deficient aromatic moieties were studied primarily by proton NMR and UV-visible spectroscopy. In solution, the anesthetic, its analogs and cocaine are electron donors and form π-π charge transfer complexes with strong aromatic acceptors, as monitored by the upfield changes induced in the NMR chemical shifts (δ) and red-shifted UV-vis wavelength (λmax) absorbance of the acceptors. The equilibrium binding constant, K, was determined from the 1H NMR charge transfer induced chemical shift changes and used to calculate the free energy (ΔG) for complex formation of three acceptor-donor pairs. HPLC results indicate that the concentrations of free bupivacaine, its analogs and of cocaine are reduced from solution via binding to aromatic-functionalized silica. PMID:18019843

  2. Stacking interaction and its role in kynurenic acid binding to glutamate ionotropic receptors.

    PubMed

    Zhuravlev, Alexander V; Zakharov, Gennady A; Shchegolev, Boris F; Savvateeva-Popova, Elena V

    2012-05-01

    Stacking interaction is known to play an important role in protein folding, enzyme-substrate and ligand-receptor complex formation. It has been shown to make a contribution into the aromatic antagonists binding with glutamate ionotropic receptors (iGluRs), in particular, the complex of NMDA receptor NR1 subunit with the kynurenic acid (KYNA) derivatives. The specificity of KYNA binding to the glutamate receptors subtypes might partially result from the differences in stacking interaction. We have calculated the optimal geometry and binding energy of KYNA dimers with the four types of aromatic amino acid residues in Rattus and Drosophila ionotropic iGluR subunits. All ab initio quantum chemical calculations were performed taking into account electron correlations at MP2 and MP4 perturbation theory levels. We have also investigated the potential energy surfaces (PES) of stacking and hydrogen bonds (HBs) within the receptor binding site and calculated the free energy of the ligand-receptor complex formation. The energy of stacking interaction depends both on the size of aromatic moieties and the electrostatic effects. The distribution of charges was shown to determine the geometry of polar aromatic ring dimers. Presumably, stacking interaction is important at the first stage of ligand binding when HBs are weak. The freedom of ligand movements and rotation within receptor site provides the precise tuning of the HBs pattern, while the incorrect stacking binding prohibits the ligand-receptor complex formation. PMID:21833825

  3. Quantifying the π-Stacking Interactions in Nitroarene Binding Sites of Proteins.

    PubMed

    An, Yi; Bloom, Jacob W G; Wheeler, Steven E

    2015-11-12

    Stacking interactions in nitroarene binding sites of proteins were studied through analyses of structures in the protein data bank (PDB), as well as DFT and ab initio computations applied to model systems. Stacked dimers of mono-, di-, and trinitrobenzene with the amino acid side chains histidine (His), phenylalanine (Phe), tyrosine (Tyr), and tryptophan (Trp) were optimized at the B97-D/TZV(2d,2p) level of theory. Binding energies for the global minimum dimer geometries were further refined at the estimated CCSD(T)/aug-cc-pVTZ level of theory. The results show that the interactions between aromatic amino acids and nitroarenes are very strong (up to -14.6 kcal mol(-1)), and the regiochemistry of the nitro substituents plays a significant role in the relative monomer orientations and strength of the interaction. In contrast to model stacked benzene dimers, effects of nitro substituents in stacking complexes with aromatic amino acid side chains are not perfectly additive. This is attributed to direct interactions of the nitro substituents with functional groups in the amino acid side chain. Overall, the strength of stacking interactions with these nitrobenzenes follows the order Trp > Tyr > Phe ≈ His. We also analyzed nitroarene binding sites in the PDB. Out of 216 selected crystal structures containing nitroarene ligands, 191 have nearby aromatic residues, providing 65 examples of π-stacking interactions involving a nitroarene. Of these, the representations of the different aromatic amino acids (Trp > Tyr > Phe > His) are correlated with the strength of model complexes of nitroarenes, with the exception of His. B97-D computations applied to complexes extracted from these crystal structures reveal that π-stacking interactions between the nitroarene and aromatic amino acid side chains exhibit a broad range of strengths, with many contributing significantly to binding. PMID:26491883

  4. Aromatic-aromatic interaction of amitriptyline: implication of overdosed drug detoxification.

    PubMed

    Lee, Dong-Won; Flint, Jason; Morey, Timothy; Dennis, Donn; Partch, Richard; Baney, Ronald

    2005-02-01

    The objectives of this work are to explore the pi-pi complexation of amitriptyline with pi electron-deficient aromatic rings and demonstrate the feasibility of pi-pi complexation for overdosed drug detoxification. Water-soluble oligochitosan was chemically modified with dinitrobenzenesulfonyl groups to induce selective binding toward amitriptyline through pi-pi complexation. NMR studies showed that benzenesulfonyl and dinitrobenzenesulfonyl protons were upfield shifted by the addition of amitriptyline, indicating the formation of pi-pi complexes. The pi-pi complexation of amitriptyline is driven primarily by a desolvation driving force, whereas the magnitude of interaction is dictated by the complementrary electrostatic interaction. Isolated rat heart tests revealed that dinitrobenzenesulfonyl oligochitosan prevented the amitriptyline-induced cardiotoxicity and was itself not cardiotoxic. PMID:15614810

  5. Understanding Stacking Interactions between an Aromatic Ring and Nucleobases in Aqueous Solution: Experimental and Theoretical Study.

    PubMed

    Kataev, Evgeny A; Shumilova, Tatiana A; Fiedler, Benjamin; Anacker, Tony; Friedrich, Joachim

    2016-08-01

    Stacking interactions between aromatic compounds and nucleobases are crucial in recognition of nucleotides and nucleic acids, but a comprehensive understanding of the strength and selectivity of these interactions in aqueous solution has been elusive. To this end, model complexes have been designed and analyzed by experiment and theory. For the first time, stacking free energies between five nucleobases and anthracene were determined experimentally from thermodynamic double mutant cycles. Three different experimental methods were proposed and evaluated. The dye prefers to bind nucleobases in the order (kcal/mol): G (1.3) > T (0.9) > U (0.8) > C (0.5) > A (0.3). The respective trend of interaction free energies extracted from DFT calculations correlates to that obtained experimentally. Analysis of the data suggests that stacking interactions dominate over hydrophobic effects in an aqueous solution and can be predicted with DFT calculations. PMID:27314892

  6. Dynamic investigation of PEFC stacks in interaction with the air supply system

    NASA Astrophysics Data System (ADS)

    Philipps, F.; Simons, G.; Schiefer, K.

    This paper explores the behaviour of a dynamically operated fuel cell system regarding to an automotive application, examining the air supply and their interaction with the fuel cell stacks. The dynamic limits of stack operation are also discussed. Finally, the paper provides a description of the test facility used in these investigations. The research of dynamically operated fuel cell stacks shows that in order to achieve high energy efficiency, a power-dependent modulation of the pressure and flow rate of the air supply is necessary. A test facility designed for energy management and power train research (up to 42 kW) was used for the experiment. A number of 11.5 kW fuel cell stacks was examined experimentally with respect to performance in interaction with the air supply in stationary and dynamic operation. The stacks were tested individually and in parallel. All of them were operated "dead-end" on the hydrogen side. Experimental results varying the parameters and load curves applied to the air supply system are given in the paper. The results show different dynamic behaviours between the stacks and a substantial difference in efficiency and dynamic response of the fuel cell system operated with different strategies. The results of different operating strategies for fuel cell systems, with respect to the interaction between the fuel cell stack and the air supply and in their dependency on air mass flow and pressure level are presented. The examinations were done with the test facility using real current demand profile of the experimental car HyLite ® from zero to full load and the New European Drive Cycle (NEDC).

  7. The stacking interactions of bipyridine complexes: the influence of the metal ion type on the strength of interactions.

    PubMed

    Sredojević, Dušan N; Petrović, Predrag V; Janjić, Goran V; Brothers, Edward N; Hall, Michael B; Zarić, Snežana D

    2016-01-01

    The strength of the stacking interactions in the bipy complexes of nickel, palladium, and platinum, [M(CN)2 bipy]2 (M = Ni, Pd, Pt), was calculated using the ωB97xD/def2-TZVP method. The results show that for all considered geometries, interactions are the strongest for platinum, and weakest for nickel complexes, as a result of higher dispersion contributions of platinum over the palladium and nickel complexes. It was also shown that strength of interactions considerably rises with an increase of the stacking overlap area. As a consequence of the favorable electrostatic term, the strength of interactions also rises when metal atom and cyano ligands are involved in the overlap with bipy ligand. The strongest interaction was calculated in the platinum complex, for the geometry that has overlap of metal and cyano ligands with bipy ligand with an energy of -39.80 kcal mol(-1). The energies for similar geometries of palladium and nickel complexes are -34.60 and -32.45 kcal mol(-1). These energies, remarkably, exceed the strength of the stacking interactions between organic aromatic molecules. These results can be of importance in all systems with stacking interactions, from materials to biomolecules. PMID:26757913

  8. Double Dalitz plot analysis of the decay B{sup 0{yields}}DK{sup +{pi}-}, D{yields}K{sub S}{sup 0{pi}+{pi}-}

    SciTech Connect

    Gershon, Tim; Poluektov, Anton

    2010-01-01

    It is shown that it is possible to perform a model-independent extraction of the Cabibbo-Kobayashi-Maskawa unitarity triangle angle {gamma} using only the decays B{sup 0{yields}}DK{sup +{pi}-} with D{yields}K{sub S}{sup 0{pi}+{pi}-} and B{sup 0{yields}}DK{sup +{pi}-} with flavor-specific D decays. The proposed method can also utilize the B{sup 0{yields}}DK{sup +{pi}-} data with CP-eigenstate decays of the D meson in a model-independent way.

  9. Double pancake bonds: pushing the limits of strong π-π stacking interactions.

    PubMed

    Cui, Zhong-hua; Lischka, Hans; Beneberu, Habtamu Z; Kertesz, Miklos

    2014-09-17

    The concept of a double-bonded pancake bonding mechanism is introduced to explain the extremely short π-π stacking contacts in dimers of dithiatriazines. While ordinary single pancake bonds occur between radicals and already display significantly shorter interatomic distances in comparison to van der Waals (vdW) contacts, the double-bonded pancake dimer is based on diradicaloid or antiaromatic molecules and exhibits even shorter and stronger intermolecular bonds that breach into the range of extremely stretched single bonds in terms of bond distances and binding energies. These properties give rise to promising possibilities in the design of new materials with high electrical conductivity and for the field of spintronics. The analysis of the double pancake bond is based on cutting edge electron correlation theory combining multireference (nondynamical) effects and dispersion (dynamical) contributions in a balanced way providing accurate interaction energies and distributions of unpaired spins. It is also shown that the present examples do not stand isolated but that similar mechanisms operate in several analogous nonradical molecular systems to form double-bonded π-stacking pancake dimers. We report on the amazing properties of a new type of stacking interaction mechanism between π conjugated molecules in the form of a "double pancake bond" which breaks the record for short intermolecular distances and provides formidable strength for some π-π stacking interactions. PMID:25203200

  10. Stacking of purines in water: the role of dipolar interactions in caffeine.

    PubMed

    Tavagnacco, L; Di Fonzo, S; D'Amico, F; Masciovecchio, C; Brady, J W; Cesàro, A

    2016-05-11

    During the last few decades it has been ascertained that base stacking is one of the major contributions stabilizing nucleic acid conformations. However, the understanding of the nature of the interactions involved in the stacking process remains under debate and it is a subject of theoretical and experimental studies. Structural similarity between purine bases (guanine and adenine) in DNA and the caffeine molecule makes caffeine an excellent model for the purine bases. The present study clearly shows that dipolar interactions play a fundamental role in determining stacking of purine molecules in solution. In order to reach this achievement, polarized ultraviolet Raman resonant scattering experiments have been carried out on caffeine aqueous solutions as a function of concentration and temperature. The investigation pointed out at the aggregation and solvation properties, particularly at elevated temperatures. Kubo-Anderson theory was used as a framework to investigate the non-coincidence effect (NCE) occurring in the totally symmetric breathing modes of the purine rings, and in the bending modes of the methyl groups of caffeine. The NCE concentration dependence shows that caffeine aggregation at 80 °C occurs by planar stacking of the hydrophobic faces. The data clearly indicate that dipolar interactions determine the reorientational motion of the molecules in solution and are the driving force for the stacking of caffeine. In parallel, the observed dephasing times imply a change in caffeine interactions as a function of temperature and concentration. A decrease, at low water content, of the dephasing time for the ring breathing vibration mode indicates that self-association alters the solvation structure that is detectable at low concentration. These results are in agreement with simulation predictions and serve as an important validation of the models used in those calculations. PMID:27127808

  11. Dynamics of dislocation interactions with stacking-fault tetrahedra at high temperature

    NASA Astrophysics Data System (ADS)

    Briceño, M.; Kacher, J.; Robertson, I. M.

    2013-02-01

    The interaction process between dislocations and large stacking-fault tetrahedra was observed in real time at high temperature during deformation experiments in situ in the transmission electron microscope. Dislocation interactions with tetrahedra resulted in them being annihilated and converted to another defect type. Dislocation bypass of the tetrahedra occurred by cross-slip. The latter interaction occurred slowly and halted the progress of the dislocation. Annihilation versus bypass by dislocation cross-slip was dictated by the location at which the slip plane intersected the tetrahedron - on the face or along the edges with the stair-rod dislocations. In general, the interactions, at best, were weakly temperature dependent.

  12. The influence of arene-ring size on stacking interaction with canonical base pairs

    NASA Astrophysics Data System (ADS)

    Formánek, Martin; Burda, Jaroslav V.

    2014-04-01

    Stacking interactions between aromatic molecules (benzene, p-cymene, biphenyl, and di- and tetra-hydrogen anthracene) and G.C and A.T canonical Watson-Crick (WC) base pairs are explored. Two functionals with dispersion corrections: ω-B97XD and B3LYP-D3 are used. For a comparison also the MP2 and B3LYP-D3/PCM methods were used for the most stable p-cymene…WC geometries. It was found that the stacking interaction increases with the size of π-conjugation system. Its extent is in agreement with experimental finding on anticancer activity of Ru(II) piano-stool complexes where intercalation of these aromatic molecules should play an important role. The explored structures are considered as ternary system so that decomposition of the interaction energy to pairwise and non-additivity contributions is also examined.

  13. An application of the van der Waals density functional: Hydrogen bonding and stacking interactions between nucleobases.

    PubMed

    Cooper, Valentino R; Thonhauser, T; Langreth, David C

    2008-05-28

    We apply the van der Waals density functional (vdW-DF) to study hydrogen bonding and stacking interactions between nucleobases. The excellent agreement of our results with high level quantum chemical calculations highlights the value of the vdW-DF for first-principles investigations of biologically important molecules. Our results suggest that, in the case of hydrogen-bonded nucleobase pairs, dispersion interactions reduce the cost of propeller twists while having a negligible effect on buckling. Furthermore, the efficient scaling of DFT methods allowed for the easy optimization of separation distance between nucleobase stacks, indicating enhancements in the interaction energy of up to 3 kcalmol over previous fixed distance calculations. We anticipate that these results are significant for extending the vdW-DF method to model larger vdW complexes and biological molecules. PMID:18513005

  14. Observation of the decay B+/--->pi+/-pi0, study of B+/--->K+/-pi0, and search for B0-->pi0pi0.

    PubMed

    Aubert, B; Barate, R; Boutigny, D; Gaillard, J-M; Hicheur, A; Karyotakis, Y; Lees, J P; Robbe, P; Tisserand, V; Zghiche, A; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kral, J F; Kukartsev, G; LeClerc, C; Levi, M E; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Romosan, A; Ronan, M T; Shelkov, V G; Telnov, A V; Wenzel, W A; Harrison, T J; Hawkes, C M; Knowles, D J; Penny, R C; Watson, A T; Watson, N K; Deppermann, T; Goetzen, K; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schmuecker, H; Steinke, M; Barlow, N R; Bhimji, W; Boyd, J T; Chevalier, N; Clark, P J; Cottingham, W N; Mackay, C; Wilson, F F; Hearty, C; Mattison, T S; McKenna, J A; Thiessen, D; Kyberd, P; McKemey, A K; Blinov, V E; Bukin, A D; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Chao, M; Kirkby, D; Lankford, A J; Mandelkern, M; McMahon, S; Mommsen, R K; Roethel, W; Stoker, D P; Buchanan, C; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Rahatlou, Sh; Schwanke, U; Sharma, V; Berryhill, J W; Campagnari, C; Dahmes, B; Kuznetsova, N; Levy, S L; Long, O; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beringer, J; Eisner, A M; Heusch, C A; Lockman, W S; Schalk, T; Schmitz, R E; Schumm, B A; Seiden, A; Turri, M; Walkowiak, W; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Narsky, I; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S; Mancinelli, G; Meadows, B T; Sokoloff, M D; Barillari, T; Blanc, F; Bloom, P; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Roy, J; Smith, J G; Van Hoek, W C; Zhang, L; Harton, J L; Hu, T; Soffer, A; Toki, W H; Wilson, R J; Zhang, J; Altenburg, D; Brandt, T; Brose, J; Colberg, T; Dickopp, M; Dubitzky, R S; Hauke, A; Lacker, H M; Maly, E; Müller-Pfefferkorn, R; Nogowski, R; Otto, S; Schubert, K R; Schwierz, R; Spaan, B; Wilden, L; Bernard, D; Bonneaud, G R; Brochard, F; Cohen-Tanugi, J; T'Jampens, S; Thiebaux, Ch; Vasileiadis, G; Verderi, M; Bernet, R; Khan, A; Lavin, D; Muheim, F; Playfer, S; Swain, J E; Tinslay, J; Borean, C; Bozzi, C; Piemontese, L; Sarti, A; Treadwell, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; De Sangro, R; Falciai, D; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Buzzo, A; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Pastore, F C; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Morii, M; Grenier, G J; Lee, S-J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Prell, S; Rosenberg, E I; Yi, J; Davier, M; Grosdidier, G; Höcker, A; Laplace, S; Le Diberder, F; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Tantot, L; Wormser, G; Bionta, R M; Brigljević, V; Cheng, C H; Lange, D J; Wright, D M; Bevan, A J; Fry, J R; Gabathuler, E; Gamet, R; Kay, M; Payne, D J; Sloane, R J; Touramanis, C; Aspinwall, M L; Bowerman, D A; Dauncey, P D; Egede, U; Eschrich, I; Morton, G W; Nash, J A; Sanders, P; Taylor, G P; Back, J J; Bellodi, G; Harrison, P F; Shorthouse, H W; Strother, P; Vidal, P B; Cowan, G; Flaecher, H U; George, S; Green, M G; Kurup, A; Marker, C E; McMahon, T R; Ricciardi, S; Salvatore, F; Vaitsas, G; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, R J; Forti, A C; Hart, P A; Jackson, F; Lafferty, G D; Lyon, A J; Weatherall, J H; Williams, J C; Farbin, A; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Staengle, H; Willocq, S; Cowan, R; Sciolla, G; Taylor, F; Yamamoto, R K; Mangeol, D J J; Milek, M; Patel, P M; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Hast, C; Taras, P; Nicholson, H; Cartaro, C; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M A; Raven, G; LoSecco, J M; Gabriel, T A; Brau, B; Pulliam, T; Brau, J; Frey, R; Iwasaki, M; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Tiozzo, G; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; de la Vaissière, Ch; Del Buono, L; Hamon, O; Leruste, Ph; Ocariz, J; Pivk, M; Roos, L; Stark, J; Manfredi, P F; Re, V; Gladney, L; Guo, Q H; Panetta, J; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Bucci, F; Calderini, G; Carpinelli, M; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Martinez-Vidal, F; Morganti, M; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Sandrelli, F; Triggiani, G; Walsh, J; Haire, M; Judd, D; Paick, K; Wagoner, D E; Danielson, N; Elmer, P; Lu, C; Miftakov, V; Olsen, J; Smith, A J S; Varnes, E W; Bellini, F; Cavoto, G; Del Re, D; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Leonardi, E; Mazzoni, M A; Morganti, S; Pierini, M; Piredda, G; Safai Tehrani, F; Serra, M; Voena, C; Christ, S; Wagner, G; Waldi, R; Adye, T; De Groot, N; Franek, B; Geddes, N I; Gopal, G P; Olaiya, E O; Xella, S M; Aleksan, R; Emery, S; Gaidot, A; Ganzhur, S F; Giraud, P-F; Hamel de Monchenault, G; Kozanecki, W; Langer, M; London, G W; Mayer, B; Schott, G; Vasseur, G; Yeche, Ch; Zito, M; Purohit, M V; Weidemann, A W; Yumiceva, F X; Aston, D; Bartoldus, R; Berger, N; Boyarski, A M; Buchmueller, O L; Convery, M R; Coupal, D P; Dong, D; Dorfan, J; Dunwoodie, W; Field, R C; Glanzman, T; Gowdy, S J; Grauges-Pous, E; Hadig, T; Halyo, V; Hryn'ova, T; Innes, W R; Jessop, C P; Kelsey, M H; Kim, P; Kocian, M L; Langenegger, U; Leith, D W G S; Luitz, S; Luth, V; Lynch, H L; Marsiske, H; Menke, S; Messner, R; Muller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Petrak, S; Ratcliff, B N; Robertson, S H; Roodman, A; Salnikov, A A; Schietinger, T; Schindler, R H; Schwiening, J; Simi, G; Snyder, A; Soha, A; Stelzer, J; Su, D; Sullivan, M K; Tanaka, H A; Va'vra, J; Wagner, S R; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wright, D H; Young, C C; Burchat, P R; Meyer, T I; Roat, C; Ahmed, S; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Kim, H; Ritchie, J L; Schwitters, R F; Izen, J M; Kitayama, I; Lou, X C; Bianchi, F; Bona, M; Gamba, D; Bosisio, L; Della Ricca, G; Dittongo, S; Grancagnolo, S; Lanceri, L; Poropat, P; Vitale, L; Vuagnin, G; Panvini, R S; Banerjee, Sw; Brown, C M; Fortin, D; Jackson, P D; Kowalewski, R; Roney, J M; Band, H R; Dasu, S; Datta, M; Eichenbaum, A M; Hu, H; Johnson, J R; Liu, R; Di Lodovico, F; Mohapatra, A K; Pan, Y; Prepost, R; Sekula, S J; von Wimmersperg-Toeller, J H; Wu, J; Wu, S L; Yu, Z; Neal, H

    2003-07-11

    We present results for the branching fractions and charge asymmetries in B+/--->h(+/-)pi(0) (where h(+/-)=pi(+/-),K+/-) and a search for the decay B0-->pi(0)pi(0) using a sample of approximately 88 x 10(6) BBmacr; pairs collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. We measure B(B+/--->pi(+/-)pi(0))=(5.5(+1.0)(-0.9)+/-0.6)x10(-6), where the first error is statistical and the second is systematic. The B+/--->pi(+/-)pi(0) signal has a significance of 7.7sigma including systematic uncertainties. We simultaneously measure the K+/-pi(0) branching fraction to be B(B+/--->K+/-pi(0))=(12.8(+1.2)(-1.1)+/-1.0)x10(-6). The charge asymmetries are Api(+/-)(pi(0))=-0.03(+0.18)(-0.17)+/-0.02 and AK+/-(pi(0))=-0.09+/-0.09+/-0.01. We place a 90% confidence-level upper limit on the branching fraction B(B0-->pi(0)pi(0)) of 3.6 x 10(-6). PMID:12906470

  15. Measurements of branching fractions and CP-violating asymmetries in B0-->pi+pi-, K+pi-, K+K- decays.

    PubMed

    Aubert, B; Boutigny, D; Gaillard, J-M; Hicheur, A; Karyotakis, Y; Lees, J P; Robbe, P; Tisserand, V; Zghiche, A; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kral, J F; LeClerc, C; Levi, M E; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Romosan, A; Ronan, M T; Shelkov, V G; Telnov, A V; Wenzel, W A; Harrison, T J; Hawkes, C M; Knowles, D J; O'Neale, S W; Penny, R C; Watson, A T; Watson, N K; Deppermann, T; Goetzen, K; Koch, H; Lewandowski, B; Peters, K; Schmuecker, H; Steinke, M; Barlow, N R; Bhimji, W; Boyd, J T; Chevalier, N; Clark, P J; Cottingham, W N; Mackay, C; Wilson, F F; Abe, K; Hearty, C; Mattison, T S; McKenna, J A; Thiessen, D; Jolly, S; McKemey, A K; Blinov, V E; Bukin, A D; Buzykaev, A R; Golubev, V B; Ivanchenko, V N; Korol, A A; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Yushkov, A N; Best, D; Chao, M; Kirkby, D; Lankford, A J; Mandelkern, M; McMahon, S; Stoker, D P; Buchanan, C; Chun, S; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H; Prell, S; Rahatlou, Sh; Raven, G; Schwanke, U; Sharma, V; Berryhill, J W; Campagnari, C; Dahmes, B; Hart, P A; Kuznetsova, N; Levy, S L; Long, O; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beringer, J; Eisner, A M; Grothe, M; Heusch, C A; Lockman, W S; Pulliam, T; Schalk, T; Schmitz, R E; Schumm, B A; Seiden, A; Turri, M; Walkowiak, W; Williams, D C; Wilson, M G; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S; Mancinelli, G; Meadows, B T; Sokoloff, M D; Barillari, T; Bloom, P; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Roy, J; Smith, J G; van Hoek, W C; Zhang, L; Harton, J L; Hu, T; Krishnamurthy, M; Soffer, A; Toki, W H; Wilson, R J; Zhang, J; Altenburg, D; Brandt, T; Brose, J; Colberg, T; Dickopp, M; Dubitzky, R S; Hauke, A; Maly, E; Müller-Pfefferkorn, R; Otto, S; Schubert, K R; Schwierz, R; Spaan, B; Wilden, L; Bernard, D; Bonneaud, G R; Brochard, F; Cohen-Tanugi, J; Ferrag, S; T'Jampens, S; Thiebaux, Ch; Vasileiadis, G; Verderi, M; Anjomshoaa, A; Bernet, R; Khan, A; Lavin, D; Muheim, F; Playfer, S; Swain, J E; Tinslay, J; Falbo, M; Borean, C; Bozzi, C; Piemontese, L; Sarti, A; Treadwell, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Falciai, D; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Bagnasco, S; Buzzo, A; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Pastore, F C; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Morii, M; Bartoldus, R; Grenier, G J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Rosenberg, E I; Yi, J; Davier, M; Grosdidier, G; Höcker, A; Lacker, H M; Laplace, S; Le Diberder, F; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Tantot, L; Trincaz-Duvoid, S; Wormser, G; Bionta, R M; Brigljević, V; Lange, D J; van Bibber, K; Wright, D M; Bevan, A J; Fry, J R; Gabathuler, E; Gamet, R; George, M; Kay, M; Payne, D J; Sloane, R J; Touramanis, C; Aspinwall, M L; Bowerman, D A; Dauncey, P D; Egede, U; Eschrich, I; Morton, G W; Nash, J A; Sanders, P; Smith, D; Taylor, G P; Back, J J; Bellodi, G; Dixon, P; Harrison, P F; Potter, R J L; Shorthouse, H W; Strother, P; Vidal, P B; Cowan, G; Flaecher, H U; George, S; Green, M G; Kurup, A; Marker, C E; McMahon, T R; Ricciardi, S; Salvatore, F; Vaitsas, G; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, R J; Forti, A C; Jackson, F; Lafferty, G D; Lyon, A J; Savvas, N; Weatherall, J H; Williams, J C; Farbin, A; Jawahery, A; Lillard, V; Roberts, D A; Schieck, J R; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Staengle, H; Willocq, S; Brau, B; Cowan, R; Sciolla, G; Taylor, F; Yamamoto, R K; Milek, M; Patel, P M; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Hast, C; Taras, P; Nicholson, H; Cartaro, C; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Paolucci, P; Piccolo, D; Sciacca, C; LoSecco, J M; Alsmiller, J R G; Gabriel, T A; Brau, J; Frey, R; Iwasaki, M; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; de la Vaissière, Ch; Del Buono, L; Hamon, O; Leruste, Ph; Ocariz, J; Pivk, M; Roos, L; Stark, J; Manfredi, P F; Re, V; Speziali, V; Gladney, L; Guo, Q H; Panetta, J; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Bucci, F; Calderini, G; Campagna, E; Carpinelli, M; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Martinez-Vidal, F; Morganti, M; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Sandrelli, F; Triggiani, G; Walsh, J; Haire, M; Judd, D; Paick, K; Turnbull, L; Wagoner, D E; Albert, J; Danielson, N; Elmer, P; Lu, C; Miftakov, V; Olsen, J; Schaffner, S F; Smith, A J S; Tumanov, A; Varnes, E W; Bellini, F; Cavoto, G; del Re, D; Faccini, R; Ferrarotto, F; Ferroni, F; Leonardi, E; Mazzoni, M A; Morganti, S; Piredda, G; Safai Tehrani, F; Serra, M; Voena, C; Christ, S; Wagner, G; Waldi, R; Adye, T; De Groot, N; Franek, B; Geddes, N I; Gopal, G P; Xella, S M; Aleksan, R; Emery, S; Gaidot, A; Giraud, P-F; Hamel de Monchenault, G; Kozanecki, W; Langer, M; London, G W; Mayer, B; Schott, G; Serfass, B; Vasseur, G; Yeche, Ch; Zito, M; Purohit, M V; Weidemann, A W; Yumiceva, F X; Adam, I; Aston, D; Berger, N; Boyarski, A M; Convery, M R; Coupal, D P; Dong, D; Dorfan, J; Dunwoodie, W; Field, R C; Glanzman, T; Gowdy, S J; Grauges, E; Haas, T; Hadig, T; Halyo, V; Himel, T; Hryn'ova, T; Huffer, M E; Innes, W R; Jessop, C P; Kelsey, M H; Kim, P; Kocian, M L; Langenegger, U; Leith, D W G S; Luitz, S; Luth, V; Lynch, H L; Marsiske, H; Menke, S; Messner, R; Muller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Petrak, S; Quinn, H; Ratcliff, B N; Robertson, S H; Roodman, A; Salnikov, A A; Schietinger, T; Schindler, R H; Schwiening, J; Simi, G; Snyder, A; Soha, A; Spanier, S M; Stelzer, J; Su, D; Sullivan, M K; Tanaka, H A; Va'vra, J; Wagner, S R; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wright, D H; Young, C C; Burchat, P R; Cheng, C H; Meyer, T I; Roat, C; Henderson, R; Bugg, W; Cohn, H; Izen, J M; Kitayama, I; Lou, X C; Bianchi, F; Bona, M; Gamba, D; Bosisio, L; Della Ricca, G; Dittongo, S; Lanceri, L; Poropat, P; Vitale, L; Vuagnin, G; Panvini, R S; Banerjee, S W; Brown, C M; Fortin, D; Jackson, P D; Kowalewski, R; Roney, J M; Band, H R; Dasu, S; Datta, M; Eichenbaum, A M; Hu, H; Johnson, J R; Liu, R; Di Lodovico, F; Mohapatra, A; Pan, Y; Prepost, R; Scott, I J; Sekula, S J; von Wimmersperg-Toeller, J H; Wu, J; Wu, S L; Yu, Z; Neal, H

    2002-12-31

    We present measurements of branching fractions and CP-violating asymmetries for two-body neutral B meson decays to charged pions and kaons based on a sample of about 88x10(6) Upsilon(4S)-->BB decays. From a time-independent fit we measure the charge-averaged branching fractions B(B0-->pi+pi-)=(4.7+/-0.6+/-0.2)x10(-6), B(B0-->K+pi-)=(17.9+/-0.9+/-0.7)x10(-6), and the direct CP-violating charge asymmetry A(Kpi)=-0.102+/-0.050+/-0.016 [-0.188,-0.016], where the ranges in square brackets indicate the 90% confidence intervals. From a time-dependent fit we measure the B0-->pi+pi- CP-violating parameters S(pipi)=0.02+/-0.34+/-0.05 [-0.54,+0.58] and C(pipi)=-0.30+/-0.25+/-0.04 [-0.72,+0.12]. PMID:12513134

  16. Measurement of D^0-\\bar{D^0} Mixing From a Time-Dependent Amplitude Analysis of D^0\\ -> K^+\\pi^-\\pi0 Decays

    SciTech Connect

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

    2008-08-04

    The authors present evidence of D{sup 0}-{bar D}{sup 0} mixing using a time-dependent amplitude analysis of the decay D{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0} in a data sample of 384 fb{sup -1} collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider at SLAC. Assuming CP conservation, they measure the mixing parameters x{prime}{sub K{pi}{pi}{sup 0}} = [2.61{sub -0.68}{sup +0.57}(stat.) {+-} 0.39(syst.)]%, y{prime}{sub K{pi}{pi}{sup 0}} = [-0.06{sub -0.64}{sup +0.55}(stat.) {+-} 0.34(syst.)]%. The confidence level for the data to be consistent with the no-mixing hypothesis is 0.1%, including systematic uncertainties. This result is inconsistent with the no-mixing hypothesis with a significance of 3.2 standard deviations. They find no evidence of CP violation in mixing.

  17. Charmed Baryon Spectroscopy and Search for $CP$ Violation in $D^0 \\to K_S^0\\,\\pi^+\\,\\pi^-$ at CDF

    SciTech Connect

    Wick, Felix

    2011-10-28

    In this thesis two different analyses are presented, namely the measurements of the properties of $\\Lambda_c(2595)^+$, $\\Lambda_c(2625)^+$, $\\Sigma_c(2455)^{++,0}$, and $\\Sigma_c(2520)^{++,0}$ baryons as well as the search for $CP$ violation in the Dalitz plot of the decay $D^0 \\to K_S^0\\,\\pi^+\\,\\pi^-$. Both studies are performed using data corresponding to 5.2\\,\\invfb respective 6.0\\,\\invfb of integrated luminosity from $p\\bar{p}$ collisions at a center-of-mass energy of 1.96\\,TeV, collected with the CDF~II detector at the Fermilab Tevatron. The masses and decay widths of the mentioned charmed baryon resonances are measured with uncertainties comparable to the world averages for $\\Sigma_c$ states, and significantly smaller uncertainties than the world averages for excited $\\Lambda_c^+$ states. No hints for any $CP$ violating effects in the resonant substructure of $D^0 \\to K_S^0\\,\\pi^+\\,\\pi^-$ are found.

  18. Determining the photon polarization of the b{yields}s{gamma} using the B{yields}K{sub 1}(1270){gamma}{yields}(K{pi}{pi}){gamma} decay

    SciTech Connect

    Kou, E.

    2011-05-01

    Recently the radiative B decay to the strange axial-vector mesons, B{yields}K{sub 1}(1270){gamma}, has been observed with a rather large branching ratio. This process is particularly interesting as the subsequent K{sub 1} decay into its three-body final state allows us to determine the polarization of the photon, which is mostly left- (right-)handed for B(B) in the SM while various new physics models predict additional right- (left-)handed components. A new method is proposed to determine the polarization, exploiting the full Dalitz plot distribution, which seems to reduce significantly the statistical errors. This polarization measurement requires, however, detailed knowledge of the K{sub 1{yields}}K{pi}{pi} strong interaction decays, namely, the various partial wave amplitudes into the several possible quasi-two-body channels, as well as their relative phases. The pattern of partial waves is especially complex for the K{sub 1}(1270). We attempt to obtain the information through the combination of an experimental input and a theoretical one, provided by the {sup 3}P{sub 0} quark-pair-creation model.

  19. Stack zooming for multifocus interaction in skewed-aspect visual spaces.

    PubMed

    Javed, Waqas; Elmqvist, Niklas

    2013-08-01

    Many 2D visual spaces have a virtually one-dimensional nature with very high aspect ratio between the dimensions: examples include time-series data, multimedia data such as sound or video, text documents, and bipartite graphs. Common among these is that the space can become very large, e.g., temperature measurements could span a long time period, surveillance video could cover entire days or weeks, and documents can have thousands of pages. Many analysis tasks for such spaces require several foci while retaining context and distance awareness. In this extended version of our IEEE PacificVis 2010 paper, we introduce a method for supporting this kind of multifocus interaction that we call stack zooming. The approach is based on building hierarchies of 1D strips stacked on top of each other, where each subsequent stack represents a higher zoom level, and sibling strips represent branches in the exploration. Correlation graphics show the relation between stacks and strips of different levels, providing context and distance awareness for the foci. The zoom hierarchies can also be used as graphical histories and for communicating insights to stakeholders and can be further extended with annotation and integrated statistics. PMID:23744266

  20. Folic acid-polydopamine nanofibers show enhanced ordered-stacking via π-π interactions.

    PubMed

    Fan, Hailong; Yu, Xiang; Liu, Yang; Shi, Zujin; Liu, Huihui; Nie, Zongxiu; Wu, Decheng; Jin, Zhaoxia

    2015-06-21

    Recent research has indicated that polydopamine and synthetic eumelanins are optoelectronic biomaterials in which one-dimensional aggregates composed of ordered-stacking oligomers have been proposed as unique organic semiconductors. However, improving the ordered-stacking of oligomers in polydopamine nanostructures is a big challenge. Herein, we first demonstrate how folic acid molecules influence the morphology and nanostructure of polydopamine via tuning the π-π interactions of oligomers. MALDI-TOF mass spectrometry reveals that porphyrin-like tetramers are characteristic of folic acid-polydopamine (FA-PDA) nanofibers. X-ray diffraction combined with simulation studies indicate that these oligomers favour aggregation into graphite-like ordered nanostructures via strong π-π interactions. High-resolution TEM characterization of carbonized FA-PDA hybrids show that in FA-PDA nanofibers the size of the graphite-like domains is over 100 nm. The addition of folic acid in polydopamine enhances the ordered stacking of oligomers in its nanostructure. Our study steps forward to discover the mystery of the structure-property relationship of FA-PDA hybrids. It paves a way to optimize the properties of PDA through the design and selection of oligomer structures. PMID:25959650

  1. Cy3-DNA Stacking Interactions Strongly Depend on the Identity of the Terminal Basepair

    PubMed Central

    Spiriti, Justin; Binder, Jennifer K.; Levitus, Marcia; van der Vaart, Arjan

    2011-01-01

    We characterized the effect of the first basepair on the conformational dynamics of the fluorescent dye Cy3 attached to the 5′ end of double-stranded DNA using Gaussian-mixture adaptive umbrella sampling simulations. In the simulations, the sampling of all five dihedral angles along the linker was enhanced, so that both stacked and unstacked states were sampled. The affinity of Cy3 for a T·A basepair (with the dye attached to T) was found to be significantly less than for the other basepairs. This was verified experimentally by measuring the activation energies for cis-trans isomerization of the dye. The simulation and experimental results indicate the existence of partially unstacked conformations amenable to photoisomerization. The simulations also showed that stacking of Cy3 straightens the DNA while stabilizing the first basepair. Our findings indicate that fluorescence is modulated by Cy3-DNA interactions in a sequence-dependent manner. PMID:21320450

  2. Measurement of CP–Violating Asymmetries in $D^0 \\to \\pi^+ \\pi^-$ and $D^0 \\to K^+ K^- $ Decays at CDF

    SciTech Connect

    Di Canto, Angelo

    2012-04-12

    We report a search for non–Standard Model physics through the measurement of CP–violating asymmetries in the singly–Cabibbo– suppressed $D^0 \\to \\pi^+ \\pi^-$ and $D^0 \\to K^+ K^- $ decays reconstructed in about 5.9 fb-1 of CDF data. We use the strong $D^{*+} \\to D^0\\pi^+$ decay (“D tag”) to identify the flavor of the charmed meson at production time and exploit CP–conserving strong cc pair–production in pp collisions. Large samples of Cabibbo–favored $D^0 \\to K^-\\pi^+$ decays with and without D tag are used to highly suppress systematic uncertainties due to detector effects. The results are the world’s most precise measurements to date and have been published by Physical Review D in January 2012 [1].

  3. Precise measurement of the e+e- --> pi+pi-(gamma) cross section with the initial state radiation method at BABAR.

    PubMed

    Aubert, B; Karyotakis, Y; Lees, J P; Poireau, V; Prencipe, E; Prudent, X; Tisserand, V; Garra Tico, J; Grauges, E; Martinelli, M; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Battaglia, M; Brown, D N; Hooberman, B; Kerth, L T; Kolomensky, Yu G; Lynch, G; Osipenkov, I L; Tackmann, K; Tanabe, T; Hawkes, C M; Soni, N; Watson, A T; Koch, H; Schroeder, T; Asgeirsson, D J; Hearty, C; Mattison, T S; McKenna, J A; Barrett, M; Khan, A; Randle-Conde, A; Blinov, V E; Bukin, A D; Buzykaev, A R; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Atmacan, H; Gary, J W; Liu, F; Long, O; Vitug, G M; Yasin, Z; Sharma, V; Campagnari, C; Hong, T M; Kovalskyi, D; Mazur, M A; Richman, J D; Beck, T W; Eisner, A M; Heusch, C A; Kroseberg, J; Lockman, W S; Martinez, A J; Schalk, T; Schumm, B A; Seiden, A; Wang, L; Winstrom, L O; Cheng, C H; Doll, D A; Echenard, B; Fang, F; Hitlin, D G; Narsky, I; Ongmongkolkul, P; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Bloom, P C; Ford, W T; Gaz, A; Hirschauer, J F; Nagel, M; Nauenberg, U; Smith, J G; Wagner, S R; Ayad, R; Toki, W H; Feltresi, E; Hauke, A; Jasper, H; Karbach, T M; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Kobel, M J; Nogowski, R; Schubert, K R; Schwierz, R; Bernard, D; Latour, E; Verderi, M; Clark, P J; Playfer, S; Watson, J E; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Fioravanti, E; Franchini, P; Luppi, E; Munerato, M; Negrini, M; Petrella, A; Piemontese, L; Santoro, V; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Contri, R; Guido, E; Lo Vetere, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Tosi, S; Morii, M; Adametz, A; Marks, J; Schenk, S; Uwer, U; Bernlochner, F U; Lacker, H M; Lueck, T; Volk, A; Dauncey, P D; Tibbetts, M; Behera, P K; Charles, M J; Mallik, U; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Arnaud, N; D'Orazio, A; Davier, M; Derkach, D; Firmino da Costa, J; Grosdidier, G; Le Diberder, F; Lepeltier, V; Lutz, A M; Malaescu, B; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wang, L L; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Burke, J P; Chavez, C A; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Touramanis, C; Bevan, A J; Clarke, C K; Di Lodovico, F; Sacco, R; Sigamani, M; Cowan, G; Paramesvaran, S; Wren, A C; Brown, D N; Davis, C L; Fritsch, M; Gradl, W; Hafner, A; Alwyn, K E; Bailey, D; Barlow, R J; Jackson, G; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Dallapiccola, C; Salvati, E; Cowan, R; Dujmic, D; Fisher, P H; Henderson, S W; Sciolla, G; Spitznagel, M; Yamamoto, R K; Zhao, M; Patel, P M; Robertson, S H; Schram, M; Biassoni, P; Lazzaro, A; Lombardo, V; Palombo, F; Stracka, S; Cremaldi, L; Godang, R; Kroeger, R; Sonnek, P; Summers, D J; Zhao, H W; Nguyen, X; Simard, M; Taras, P; Nicholson, H; De Nardo, G; Lista, L; Monorchio, D; Onorato, G; Sciacca, C; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; LoSecco, J M; Wang, W F; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Sekula, S J; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Castelli, G; Gagliardi, N; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; del Amo Sanchez, P; Ben-Haim, E; Bonneaud, G R; Briand, H; Chauveau, J; Hamon, O; Leruste, Ph; Marchiori, G; Ocariz, J; Perez, A; Prendki, J; Sitt, S; Gladney, L; Biasini, M; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Calderini, G; Carpinelli, M; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Lopes Pegna, D; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Anulli, F; Baracchini, E; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Renga, F; Voena, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Franek, B; Olaiya, E O; Wilson, F F; Emery, S; Esteve, L; Hamel de Monchenault, G; Kozanecki, W; Vasseur, G; Yèche, Ch; Zito, M; Allen, M T; Aston, D; Bard, D J; Bartoldus, R; Benitez, J F; Cenci, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Franco Sevilla, M; Fulsom, B G; Gabareen, A M; Graham, M T; Grenier, P; Hast, C; Innes, W R; Kaminski, J; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Lindquist, B; Luitz, S; Luth, V; Lynch, H L; MacFarlane, D B; Marsiske, H; Messner, R; Muller, D R; Neal, H; Nelson, S; O'Grady, C P; Ofte, I; Perl, M; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; Wagner, A P; Weaver, M; West, C A; Wisniewski, W J; Wittgen, M; Wright, D H; Wulsin, H W; Yarritu, A K; Young, C C; Ziegler, V; Chen, X R; Liu, H; Park, W; Purohit, M V; White, R M; Wilson, J R; Bellis, M; Burchat, P R; Edwards, A J; Miyashita, T S; Ahmed, S; Alam, M S; Ernst, J A; Pan, B; Saeed, M A; Zain, S B; Soffer, A; Spanier, S M; Wogsland, B J; Eckmann, R; Ritchie, J L; Ruland, A M; Schilling, C J; Schwitters, R F; Wray, B C; Drummond, B W; Izen, J M; Lou, X C; Bianchi, F; Gamba, D; Pelliccioni, M; Bomben, M; Bosisio, L; Cartaro, C; Della Ricca, G; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martinez-Vidal, F; Milanes, D A; Oyanguren, A; Albert, J; Banerjee, Sw; Bhuyan, B; Choi, H H F; Hamano, K; King, G J; Kowalewski, R; Lewczuk, M J; Nugent, I M; Roney, J M; Sobie, R J; Gershon, T J; Harrison, P F; Ilic, J; Latham, T E; Mohanty, G B; Puccio, E M T; Band, H R; Chen, X; Dasu, S; Flood, K T; Pan, Y; Prepost, R; Vuosalo, C O; Wu, S L

    2009-12-01

    A precise measurement of the cross section of the process e(+)e(-) --> pi(+)pi(-)(gamma) from threshold to an energy of 3 GeV is obtained with the initial state radiation (ISR) method using 232 fb(-1) of data collected with the BABAR detector at e(+)e(-) center-of-mass energies near 10.6 GeV. The ISR luminosity is determined from a study of the leptonic process e(+)e(-) --> mu(+)mu(-)gamma(gamma). The leading-order hadronic contribution to the muon magnetic anomaly calculated using the pipi cross section measured from threshold to 1.8 GeV is (514.1 +/- 2.2(stat) +/- 3.1(syst)) x 10(-10). PMID:20366141

  4. Measurement of D{0}-D[-over]{0} mixing from a time-dependent amplitude analysis of D{0}-->K+pi{-}pi{0} decays.

    PubMed

    Aubert, B; Bona, M; Karyotakis, Y; Lees, J P; Poireau, V; Prencipe, E; Prudent, X; Tisserand, V; Tico, J Garra; Grauges, E; Lopez, L; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Abrams, G S; Battaglia, M; Brown, D N; Cahn, R N; Jacobsen, R G; Kerth, L T; Kolomensky, Yu G; Lynch, G; Osipenkov, I L; Ronan, M T; Tackmann, K; Tanabe, T; Hawkes, C M; Soni, N; Watson, A T; Koch, H; Schroeder, T; Walker, D; Asgeirsson, D J; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Barrett, M; Khan, A; Blinov, V E; Bukin, A D; Buzykaev, A R; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Gary, J W; Liu, F; Long, O; Shen, B C; Vitug, G M; Yasin, Z; Zhang, L; Sharma, V; Campagnari, C; Hong, T M; Kovalskyi, D; Mazur, M A; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Schalk, T; Schumm, B A; Seiden, A; Wang, L; Wilson, M G; Winstrom, L O; Cheng, C H; Doll, D A; Echenard, B; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Bloom, P C; Ford, W T; Gaz, A; Hirschauer, J F; Nagel, M; Nauenberg, U; Smith, J G; Ulmer, K A; Wagner, S R; Ayad, R; Soffer, A; Toki, W H; Wilson, R J; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Karbach, M; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Kobel, M J; Mader, W F; Nogowski, R; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Playfer, S; Watson, J E; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Franchini, P; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Santoro, V; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Chaisanguanthum, K S; Morii, M; Marks, J; Schenk, S; Uwer, U; Klose, V; Lacker, H M; Bard, D J; Dauncey, P D; Nash, J A; Vazquez, W Panduro; Tibbetts, M; Behera, P K; Chai, X; Charles, M J; Mallik, U; Cochran, J; Crawley, H B; Dong, L; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Lae, C K; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Béquilleux, J; D'Orazio, A; Davier, M; da Costa, J Firmino; Grosdidier, G; Höcker, A; Lepeltier, V; Le Diberder, F; Lutz, A M; Pruvot, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Burke, J P; Chavez, C A; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Touramanis, C; Bevan, A J; Clarke, C K; George, K A; Di Lodovico, F; Sacco, R; Sigamani, M; Cowan, G; Flaecher, H U; Hopkins, D A; Paramesvaran, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Alwyn, K E; Bailey, D; Barlow, R J; Chia, Y M; Edgar, C L; Jackson, G; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Dallapiccola, C; Li, X; Salvati, E; Saremi, S; Cowan, R; Dujmic, D; Fisher, P H; Koeneke, K; Sciolla, G; Spitznagel, M; Taylor, F; Yamamoto, R K; Zhao, M; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Simard, M; Taras, P; Viaud, F B; Nicholson, H; De Nardo, G; Lista, L; Monorchio, D; Onorato, G; Sciacca, C; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; LoSecco, J M; Wang, W F; Benelli, G; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Sekula, S J; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Castelli, G; Gagliardi, N; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Sanchez, P del Amo; Ben-Haim, E; Briand, H; Calderini, G; Chauveau, J; David, P; Del Buono, L; Hamon, O; Leruste, Ph; Ocariz, J; Perez, A; Prendki, J; Sitt, S; Gladney, L; Biasini, M; Covarelli, R; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Carpinelli, M; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Pegna, D Lopes; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Anulli, F; Baracchini, E; Cavoto, G; del Re, D; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Gioi, L Li; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Renga, F; Voena, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Franek, B; Olaiya, E O; Wilson, F F; Emery, S; Escalier, M; Esteve, L; Ganzhur, S F; de Monchenault, G Hamel; Kozanecki, W; Vasseur, G; Yèche, Ch; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; White, R M; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Bechtle, P; Benitez, J F; Cenci, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Gabareen, A M; Gowdy, S J; Graham, M T; Grenier, P; Hast, C; Innes, W R; Kaminski, J; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Lindquist, B; Luitz, S; Luth, V; Lynch, H L; MacFarlane, D B; Marsiske, H; Messner, R; Muller, D R; Neal, H; Nelson, S; O'Grady, C P; Ofte, I; Perazzo, A; Perl, M; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; Wagner, A P; Weaver, M; West, C A; Wisniewski, W J; Wittgen, M; Wright, D H; Wulsin, H W; Yarritu, A K; Yi, K; Young, C C; Ziegler, V; Burchat, P R; Edwards, A J; Majewski, S A; Miyashita, T S; Petersen, B A; Wilden, L; Ahmed, S; Alam, M S; Ernst, J A; Pan, B; Saeed, M A; Zain, S B; Spanier, S M; Wogsland, B J; Eckmann, R; Ritchie, J L; Ruland, A M; Schilling, C J; Schwitters, R F; Drummond, B W; Izen, J M; Lou, X C; Bianchi, F; Gamba, D; Pelliccioni, M; Bomben, M; Bosisio, L; Cartaro, C; Ricca, G Della; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martinez-Vidal, F; Milanes, D A; Oyanguren, A; Albert, J; Banerjee, Sw; Bhuyan, B; Choi, H H F; Hamano, K; Kowalewski, R; Lewczuk, M J; Nugent, I M; Roney, J M; Sobie, R J; Gershon, T J; Harrison, P F; Ilic, J; Latham, T E; Mohanty, G B; Band, H R; Chen, X; Dasu, S; Flood, K T; Pan, Y; Pierini, M; Prepost, R; Vuosalo, C O; Wu, S L

    2009-11-20

    We present evidence of D{0}-D[-over ]{0} mixing using a time-dependent amplitude analysis of the decay D{0}-->K+pi{-}pi;{0} in a data sample of 384 fb{-1} collected with the BABAR detector at the PEP-II e+e{-} collider at the Stanford Linear Accelerator Center. Assuming CP conservation, we measure the mixing parameters x{Kpipi{0}}{'}=[2.61{-0.68}{+0.57}(stat)+/-0.39(syst)]%, y{Kpipi;{0}}{'}=[-0.06{-0.64}{+0.55}(stat)+/-0.34(syst)]%. This result is inconsistent with the no-mixing hypothesis with a significance of 3.2 standard deviations. We find no evidence of CP violation in mixing. PMID:20366027

  5. Limits on D0-macro D0 mixing and CP violation from the ratio of lifetimes for decay to K-pi+, K-K+, and pi- pi+.

    PubMed

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

    2003-09-19

    We present a measurement of D0-macro D0 mixing parameters using the ratios of lifetimes extracted from samples of D0 mesons decaying to K-pi(+), K-K+, and pi(-)pi(+). Using 91 fb(-1) of data collected by the BABAR detector at the PEP-II asymmetric-energy B Factory, we obtain a value Y=[0.8+/-0.4(stat.)(+0.5)(-0.4)(syst.)]%, which, in the limit of CP conservation, corresponds to the mixing parameter y=Delta Gamma/2 Gamma. Using the difference in lifetimes of D0 and macro D0 mesons, we obtain the CP-violation parameter Delta Y=[-0.8+/-0.6(stat.)+/-0.2(syst.)]%. PMID:14525353

  6. Lattice extraction of K{yields}{pi}{pi} amplitudes to next-to-leading order in partially quenched and in full chiral perturbation theory

    SciTech Connect

    Laiho, Jack; Soni, Amarjit

    2005-01-01

    We show that it is possible to construct {epsilon}{sup '}/{epsilon} to next-to-leading order (NLO) using partially quenched chiral perturbation theory (PQChPT) from amplitudes that are computable on the lattice. We demonstrate that none of the needed amplitudes require 3-momentum on the lattice for either the full theory or the partially quenched theory; nondegenerate quark masses suffice. Furthermore, we find that the electro-weak penguin ({delta}I=3/2 and 1/2) contributions to {epsilon}{sup '}/{epsilon} in PQChPT can be determined to NLO using only degenerate (m{sub K}=m{sub {pi}}) K{yields}{pi} computations without momentum insertion. Issues pertaining to power divergent contributions, originating from mixing with lower dimensional operators, are addressed. Direct calculations of K{yields}{pi}{pi} at unphysical kinematics are plagued with enhanced finite volume effects in the (partially) quenched theory, but in simulations when the sea quark mass is equal to the up and down quark mass the enhanced finite volume effects vanish to NLO in PQChPT. In embedding the QCD penguin left-right operator onto PQChPT an ambiguity arises, as first emphasized by Golterman and Pallante. With one version [the 'PQS' (patially quenched singlet)] of the QCD penguin, the inputs needed from the lattice for constructing K{yields}{pi}{pi} at NLO in PQChPT coincide with those needed for the full theory. Explicit expressions for the finite logarithms emerging from our NLO analysis to the above amplitudes also are given.

  7. Doping Dependence of the $(\\pi,\\pi)$ Shadow Band in La-Based Cuprates Studied by Angle-Resolved Photoemission Spectroscopy

    SciTech Connect

    Shen, Z. X.

    2011-08-15

    The ({pi},{pi}) shadow band (SB) in La-based cuprate family (La214) was studied by angle-resolved photoemission spectroscopy (ARPES) over a wide doping range from x = 0.01 to x = 0.25. Unlike the well-studied case of the Bi-based cuprate family, an overall strong, monotonic doping dependence of the SB intensity at the Fermi level (E{sub F}) was observed. In contrast to a previous report for the presence of the SB only close to x = 1/8, we found it exists in a wide doping range, associated with a doping-independent ({pi},{pi}) wave vector but strongly doping-dependent intensity: It is the strongest at x {approx} 0.03 and systematically diminishes as the doping increases until it becomes negligible in the overdoped regime. This SB with the observed doping dependence of intensity can in principle be caused by the antiferromagnetic fluctuations or a particular form of low-temperature orthorhombic lattice distortion known to persist up to x {approx} 0.21 in the system, with both being weakened with increasing doping. However, a detailed binding energy dependent analysis of the SB at x = 0.07 does not appear to support the former interpretation, leaving the latter as a more plausible candidate, despite a challenge in quantitatively linking the doping dependences of the SB intensity and the magnitude of the lattice distortion. Our finding highlights the necessity of a careful and global consideration of the inherent structural complications for correctly understanding the cuprate Fermiology and its microscopic implication.

  8. Interlayer-interaction dependence of latent heat in the Heisenberg model on a stacked triangular lattice with competing interactions

    NASA Astrophysics Data System (ADS)

    Tamura, Ryo; Tanaka, Shu

    2013-11-01

    We study the phase transition behavior of a frustrated Heisenberg model on a stacked triangular lattice by Monte Carlo simulations. The model has three types of interactions: the ferromagnetic nearest-neighbor interaction J1 and antiferromagnetic third nearest-neighbor interaction J3 in each triangular layer and the ferromagnetic interlayer interaction J⊥. Frustration comes from the intralayer interactions J1 and J3. We focus on the case that the order parameter space is SO(3)×C3. We find that the model exhibits a first-order phase transition with breaking of the SO(3) and C3 symmetries at finite temperature. We also discover that the transition temperature increases but the latent heat decreases as J⊥/J1 increases, which is opposite to the behavior observed in typical unfrustrated three-dimensional systems.

  9. Extracting Drug-Drug Interaction from the Biomedical Literature Using a Stacked Generalization-Based Approach

    PubMed Central

    He, Linna; Yang, Zhihao; Zhao, Zhehuan; Lin, Hongfei; Li, Yanpeng

    2013-01-01

    Drug-drug interaction (DDI) detection is particularly important for patient safety. However, the amount of biomedical literature regarding drug interactions is increasing rapidly. Therefore, there is a need to develop an effective approach for the automatic extraction of DDI information from the biomedical literature. In this paper, we present a Stacked Generalization-based approach for automatic DDI extraction. The approach combines the feature-based, graph and tree kernels and, therefore, reduces the risk of missing important features. In addition, it introduces some domain knowledge based features (the keyword, semantic type, and DrugBank features) into the feature-based kernel, which contribute to the performance improvement. More specifically, the approach applies Stacked generalization to automatically learn the weights from the training data and assign them to three individual kernels to achieve a much better performance than each individual kernel. The experimental results show that our approach can achieve a better performance of 69.24% in F-score compared with other systems in the DDI Extraction 2011 challenge task. PMID:23785452

  10. Silver(I) complexes in coordination supramolecular system with bulky acridine-based ligands: syntheses, crystal structures, and theoretical investigations on C-H...Ag close interaction.

    PubMed

    Liu, Chun-Sen; Chen, Pei-Quan; Yang, En-Cui; Tian, Jin-Lei; Bu, Xian-He; Li, Zheng-Ming; Sun, Hong-Wei; Lin, Zhenyang

    2006-07-24

    In our efforts to investigate the coordination architectures of transition metals and organic ligands with tailored structures, we have prepared two structurally related rigid bulky acridine-based ligands, 9-[3-(2-pyridyl)pyrazol-1-yl]- acridine (L(1)) and 9-(1-imidazolyl)acridine (L2), and synthesized and characterized four of their Ag(I) complexes, {[AgL1](ClO4)}2 (1), {[AgL1](NO3)}2 (2), [AgL2(2)](ClO4) (3), and {[(Ag3L2(3))(NO3)](NO3)2(H2O)}(infinity) (4). The single-crystal X-ray diffraction analysis shows that the structures of 1 and 2 are similar to each other, with the two intramolecular Ag(I) centers of each complex being encircled by two L1 ligands; this forms a unique boxlike cyclic dimer, which is further linked to form one-dimensional (1D) chains of 1 and a two-dimensional (2D) network of 2 by intermolecular face-to-face pi...pi stacking and/or weak C-H...O hydrogen-bonding interactions, respectively. 3 has a mononuclear structure, which is further assembled into a 2D network via intermolecular Ag...O and pi...pi stacking weak interactions. 4 possesses two different 1D motifs that are further interlinked through interlayer face-to-face pi...pi stacking and Ag...O weak interactions, resulting in a 2D network. It is worth noting that one of the interesting structural features of 1, 2, and 4 is the presence of obvious C-H...M hydrogen-bonding interactions between the Ag centers and some acridine ring H atoms identified by X-ray diffraction on the basis of the van der Waals radii. Furthermore, as a representative example, full geometry optimization on the basis of the experimental structure, the natural bond orbital (NBO), and topological analysis of 1 were carried out by DFT and AIM (Atoms in Molecules) calculations. The total C-H...Ag interaction energy in 1 is estimated to be about 14 kJ/mol. Therefore, this work offers three new rare examples (1, 2, and 4) that exhibit C-H...Ag weak interactions, in which the N donors of the acridine rings coordinate

  11. Dislocation-stacking fault tetrahedron interaction: what can we learn from atomic scale modelling.

    SciTech Connect

    Osetskiy, Yury N; Stoller, Roger E; Matsukawa, Yoshitaka

    2004-01-01

    The high number density of stacking fault tetrahedra (SFTs) observed in irradiated fcc metals suggests that they should contribute to radiation-induced hardening and, therefore, taken into account when estimating mechanical properties changes of irradiated materials. The central issue is describing the individual interaction between a moving dislocation and an SFT, which is characterized by a very fine size scale, {approx}100 nm. This scale is amenable to both in situ TEM experiments and large-scale atomic modelling. In this paper we present results of an atomistic simulation of dislocation-SFT interactions using molecular dynamics (MD). The results are compared with observations from in situ deformation experiments. It is demonstrated that in some cases the simulations and experimental observations are quite similar, suggesting a reasonable interpretation of experimental observations.

  12. Determination of Base Binding Strength and Base Stacking Interaction of DNA Duplex Using Atomic Force Microscope

    PubMed Central

    Zhang, Tian-biao; Zhang, Chang-lin; Dong, Zai-li; Guan, Yi-fu

    2015-01-01

    As one of the most crucial properties of DNA, the structural stability and the mechanical strength are attracting a great attention. Here, we take advantage of high force resolution and high special resolution of Atom Force Microscope and investigate the mechanical force of DNA duplexes. To evaluate the base pair hydrogen bond strength and base stacking force in DNA strands, we designed two modes (unzipping and stretching) for the measurement rupture forces. Employing k-means clustering algorithm, the ruptured force are clustered and the mean values are estimated. We assessed the influence of experimental parameters and performed the force evaluation for DNA duplexes of pure dG/dC and dA/dT base pairs. The base binding strength of single dG/dC and single dA/dT were estimated to be 20.0 ± 0.2 pN and 14.0 ± 0.3 pN, respectively, and the base stacking interaction was estimated to be 2.0 ± 0.1 pN. Our results provide valuable information about the quantitative evaluation of the mechanical properties of the DNA duplexes. PMID:25772017

  13. Influence of the π–π interaction on the hydrogen bonding capacity of stacked DNA/RNA bases

    PubMed Central

    Mignon, Pierre; Loverix, Stefan; Steyaert, Jan; Geerlings, Paul

    2005-01-01

    The interplay between aromatic stacking and hydrogen bonding in nucleobases has been investigated via high-level quantum chemical calculations. The experimentally observed stacking arrangement between consecutive bases in DNA and RNA/DNA double helices is shown to enhance their hydrogen bonding ability as opposed to gas phase optimized complexes. This phenomenon results from more repulsive electrostatic interactions as is demonstrated in a model system of cytosine stacked offset-parallel with substituted benzenes. Therefore, the H-bonding capacity of the N3 and O2 atoms of cytosine increases linearly with the electrostatic repulsion between the stacked rings. The local hardness, a density functional theory-based reactivity descriptor, appears to be a key index associated with the molecular electrostatic potential (MEP) minima around H-bond accepting atoms, and is inversely proportional to the electrostatic interaction between stacked molecules. Finally, the MEP minima on surfaces around the bases in experimental structures of DNA and RNA–DNA double helices show that their hydrogen bonding capacity increases when taking more neighboring (intra-strand) stacking partners into account. PMID:15788750

  14. Self-induced uniaxial strain in MoS2 monolayers with local van der Waals-stacked interlayer interactions.

    PubMed

    Zhang, Kenan; Hu, Shuhong; Zhang, Yun; Zhang, Tianning; Zhou, Xiaohao; Sun, Yan; Li, Tian-Xin; Fan, Hong Jin; Shen, Guozhen; Chen, Xin; Dai, Ning

    2015-03-24

    Strain engineering is an effective method to tune the properties of electrons and phonons in semiconductor materials, including two-dimensional (2D) layered materials (e.g., MoS2 or graphene). External artificial stress (ExAS) or heterostructure stacking is generally required to induce strains for modulating semiconductor bandgaps and optoelectronic functions. For layered materials, the van der Waals-stacked interlayer interaction (vdW-SI) has been considered to dominate the interlayer stacking and intralayer bonding. Here, we demonstrate self-induced uniaxial strain in the MoS2 monolayer without the assistance of ExAS or heterostructure stacking processes. The uniaxial strain occurring in local monolayer regions is manifested by the Raman split of the in-plane vibration modes E2g(1) and is essentially caused by local vdW-SI within the single layer MoS2 due to a unique symmetric bilayer stacking. The local stacked configuration and the self-induced uniaxial strain may provide improved understanding of the fundamental interlayer interactions and alternative routes for strain engineering of layered structures. PMID:25716291

  15. Measurement of gamma in B-+ to D(*) K-+ and B-+ to D K*-+ Decays with a Dalitz Analysis of D to Ks pi- pi+

    SciTech Connect

    Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; Grauges, E.; Palano, A.; Pappagallo, M.; Pompili, A.; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; Eigen, G.; Ofte, I.; Stugu, B. /Bergen U. /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /Pisa U. /Pisa, Scuola Normale Superiore /INFN, Pisa /Prairie View A-M /Princeton U. /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Vanderbilt U. /Victoria U. /Warwick U. /Wisconsin U., Madison /Yale U.

    2005-08-04

    We present a measurement of the Cabibbo-Kobayashi-Maskawa CP-violating phase {gamma} with a Dalitz plot analysis of neutral D-meson decays to the K{sub S}{sup 0} {pi}{sup -}{pi}{sup +} final state from B{sup {-+}} {yields} D{sup (*)}K{sup {-+}} and B{sup {-+}} {yields} DK*{sup {-+}} decays, using a sample of 227 million B{bar B} pairs collected by the BABAR detector. We measure {gamma} = (67 {+-} 28 {+-} 13 {+-} 11){sup o}, where the first error is statistical, the second is the experimental systematic uncertainty and the third reflects the Dalitz model uncertainty. This result suffers from a two-fold ambiguity. The contribution to the Dalitz model uncertainty due to the description of the {pi}{pi} S-wave in D{sup 0} {yields} K{sub S}{sup 0}{pi}{sup -}{pi}{sup +}, evaluated using a K-matrix formalism, is found to be 3{sup o}.

  16. Measurement of the Cabibbo-Kobayashi-Maskawa angle gamma in B+/--->D*K+/- decays with a Dalitz analysis of D-->K0(S)pi-pi+.

    PubMed

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

    2005-09-16

    We report on a measurement of the Cabibbo-Kobayashi-Maskawa CP-violating phase gamma through a Dalitz analysis of neutral D decays to K0(S)pi-pi+ in the processes B+/- -->D*K+/-, D*-->Dpi0, Dgamma. Using a sample of 227 x 10(6) BB pairs collected by the BABAR detector, we measure the amplitude ratios r(B)=0.12+/-0.03+/-0.04 and r*(B)=0.17+/-0.10+/-0.03+/-0.03, the relative strong phases delta(B)=(104+/-45(+17+16)(-21-24))degrees and delta*(B)=(-64+/-41(+14)(-12)+/-15) degrees between the amplitudes A(B- -->D*0K-) and A(B- -->D*0)K-), and gamma=(70+/-31(+12+14)(-10-11))degrees. The first error is statistical, the second is the experimental systematic uncertainty, and the third reflects the Dalitz model uncertainty. The results for the strong and weak phases have a twofold ambiguity. PMID:16197065

  17. Atomic-Scale Study of Dislocation-Stacking Fault Tetrahedron Interactions. Part I: Mechanisms.

    SciTech Connect

    Osetskiy, Yury N; Rodney, David; Bacon, David J

    2006-01-01

    Stacking fault tetrahedra (SFTs) are formed under irradiation in fcc metals and alloys. The high number density of SFTs observed suggests that they should contribute to radiation-induced hardening and, therefore, be taken into account when estimating mechanical property changes of irradiated materials. The key issue in this is to describe the interaction between a moving dislocation and an individual SFT, which is distinguished by a small physical size of the order of {approx}1-10 nm. We have performed atomistic simulations of edge and screw dislocations interacting with SFTs of different sizes at different temperatures and strain rates. Five possible interaction outcomes have been identified, involving either partial absorption, or shearing or restoration of SFTs. The mechanisms that give rise to these processes are described and their dependence on interaction parameters, such as SFT size, dislocation-SFT geometry, temperature and stress/strain rate are determined. Mechanisms that help to explain the formation of defect-free channels cleared by gliding dislocations, as observed experimentally, are also discussed. Hardening due to the various mechanisms and their dependence on loading conditions will be presented in a following paper (Part II).

  18. New nucleotide pairs for stable DNA triplexes stabilized by stacking interaction.

    PubMed

    Mizuta, Masahiro; Banba, Jun-ichi; Kanamori, Takashi; Tawarada, Ryuya; Ohkubo, Akihiro; Sekine, Mitsuo; Seio, Kohji

    2008-07-30

    New nucleotide pairs applicable to formation of DNA triplexes were developed. We designed oligonucleotides incorporating 5-aryl deoxycytidine derivatives (dC5Ars) and cyclic deoxycytidine derivatives, dCPPP and dCPPI, having an expanded aromatic area, as the second strand. As pairing partners, two types of abasic residues (C3: propylene linker, phi: abasic base) were chosen. It was concluded that, when the 5-aryl-modified cytosine bases paired with the abasic sites in TFOs in a space-fitting manner, the stability of the resulting triplexes significantly increased. The recognition of C3 toward dC5Ars was selective because of the stacking interactions between their aromatic part and the nucleobases flanking the abasic site. These results indicate the potential utility of new nucleotide triplets for DNA triplex formation, which might expand the variety of structures and sequences and might be useful for biorelated fields such as DNA nanotechnologies. PMID:18611007

  19. CDF Grid computing and the decay X(3872) ---> J/psi pi+ pi- with J/psi ---> e+ e-

    SciTech Connect

    Kerzel, Ulrich; /Karlsruhe U., EKP

    2005-11-01

    The main aim of physics research is to obtain a consistent description of nature leading to a detailed understanding of the phenomena observed in experiments. The field of particle physics focuses on the discovery and understanding of the fundamental particles and the forces by which they interact with each other. Using methods from group theory, the present knowledge can be mathematically described by the so-called ''Standard Model'', which interprets the fundamental particles (quarks and leptons) as quantum-mechanical fields interacting via the electromagnetic, weak and strong force. These interactions are mediated via gauge particles such as the photon (for the electromagnetic force), W{sup {+-}} and Z{sup 0} (for the weak force) and gluons (for the strong force). Gravitation is not yet included in this description as it presently cannot be formulated in a way to be incorporated in the Standard Model. However, the gravitational force is negligibly small on microscopic levels. The validity of this mathematical approach is tested experimentally by accelerating particles such as electrons and protons, as well as their antiparticles, to high energies and observing the reactions as these particles collide using sophisticated detectors. Due to the high energy of the particles involved, these detectors need to be as big as a small house to allow for precision measurements. Comparing the predictions from theory with the analyzed reactions observed in these collisions, the Standard Model has been established as a well-founded theory. Precision measurements from the four experiments (Aleph, Delphi, Opal, L3) the Large Electron Positron collider (LEP), operated at CERN during the years 1989-2000, allow the determination of the Standard Model parameters with enormous accuracy.

  20. Hybrid simulation approach incorporating microscopic interaction along with rigid body degrees of freedom for stacking between base pairs.

    PubMed

    Mondal, Manas; Halder, Sukanya; Chakrabarti, Jaydeb; Bhattacharyya, Dhananjay

    2016-04-01

    Stacking interaction between the aromatic heterocyclic bases plays an important role in the double helical structures of nucleic acids. Considering the base as rigid body, there are total of 18 degrees of freedom of a dinucleotide step. Some of these parameters show sequence preferences, indicating that the detailed atomic interactions are important in the stacking. Large variants of non-canonical base pairs have been seen in the crystallographic structures of RNA. However, their stacking preferences are not thoroughly deciphered yet from experimental results. The current theoretical approaches use either the rigid body degrees of freedom where the atomic information are lost or computationally expensive all atom simulations. We have used a hybrid simulation approach incorporating Monte-Carlo Metropolis sampling in the hyperspace of 18 stacking parameters where the interaction energies using AMBER-parm99bsc0 and CHARMM-36 force-fields were calculated from atomic positions. We have also performed stacking energy calculations for structures from Monte-Carlo ensemble by Dispersion corrected density functional theory. The available experimental data with Watson-Crick base pairs are compared to establish the validity of the method. Stacking interaction involving A:U and G:C base pairs with non-canonical G:U base pairs also were calculated and showed that these structures were also sequence dependent. This approach could be useful to generate multiscale modeling of nucleic acids in terms of coarse-grained parameters where the atomic interactions are preserved. This method would also be useful to predict structure and dynamics of different base pair steps containing non Watson-Crick base pairs, as found often in the non-coding RNA structures. © 2015 Wiley Periodicals, Inc. Biopolymers 105: 212-226, 2016. PMID:26600167

  1. Simulation of the photodeactivation of formamide in the nO-pi* and pi-pi* states: an ab initio on-the-fly surface-hopping dynamics study.

    PubMed

    Antol, Ivana; Eckert-Maksić, Mirjana; Barbatti, Mario; Lischka, Hans

    2007-12-21

    The short-time photodynamics (1 ps) of formamide in its low-lying singlet excited n(O)-pi(*) and pi-pi(*) states have been investigated by the direct trajectory surface-hopping method based on multiconfigurational ab initio calculations. The simulations showed that in both states, the primary deactivation process is C-N bond dissociation. In the ground state, the energy is transferred to (a) translational motion of the HCO and NH(2) fragments, (b) additional C-H dissociation from the vibrationally hot HCO fragment, or (c) formation of NH(3) and CO. In addition to the C-N dissociation pathway, C-O bond fission is found to be an additional primary deactivation path in the pi-pi(*) dynamics. From fractional occupations of trajectories, lifetimes of formamide were estimated: tau(S(1))=441 fs and tau(S(2))=66 fs. PMID:18154378

  2. C--H...O hydrogen-bonding and C--H...pi interactions in 3-(4-fluorophenyl)-1,5,7-trimethyl-1,2,3,4-tetrahydropyrido[2,3-d]pyrimidine-2,4-dione.

    PubMed

    Patel, Urmila H; Patel, Pinal D; Thakker, Neha

    2007-06-01

    In the title compound, C(16)H(14)FN(3)O(2), a diverse set of weak intermolecular C--H...pi, pi-pi and C--H...O interactions link the molecules into sheets. The C--H...O interactions generate centrosymmetric rings with a graph-set motif of R(2)(2)(14) and chains with a C(8) motif. PMID:17551197

  3. Dalitz Plot Analysis of Ds+->pi+pi-pi+

    SciTech Connect

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

    2009-01-26

    A Dalitz plot analysis of {approx} 13, 000 D{sub s}{sup +} decays to {pi}{sup +}{pi}{sup +}{pi}{sup -} has been performed. A 384 fb{sup -1} data sample, recorded by the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} storage ring running at center of mass energies near 10.6 GeV, is used. Amplitudes and phases of the intermediate resonances which contribute to this final state are measured. A high precision measurement of the ratio: {Beta}(D{sub s}{sup +} {yields} {pi}{sup +}{pi}{sup +}{pi}{sup -})/{Beta}(D{sub s}{sup +} {yields} K{sup +}K{sup -}{pi}{sup +}) = 0.199 {+-} 0.004 {+-} 0.006 is performed. Using a model independent partial wave analysis the amplitude and phase of the S-wave have been measured.

  4. Dalitz Plot Analysis of B+- --> pi+-pi+-pi-+ Decays

    SciTech Connect

    Collaboration, The BABAR; Aubert, B.

    2009-02-23

    The authors present a Dalitz-plot analysis of charmless B{sup {+-}} decays to the final state {pi}{sup {+-}}{pi}{sup {+-}}{pi}{sup {-+}} using a sample of (465 {+-} 5) x 10{sup 6} B{bar B} pairs collected by the BABAR experiment at {radical}s = 10.58 GeV. They measure the branching fractions {Beta}(B{sup {+-}} {yields} {pi}{sup {+-}}{pi}{sup {+-}}{pi}{sup {-+}}) = (15.2 {+-} 0.6 {+-} 1.2 {+-} 0.4) x 10{sup -6}, {Beta}(B{sup {+-}} {yields} {rho}{sup 0}(770){pi}{sup {+-}}) = (8.1 {+-} 0.7 {+-} 1.2{sub -1.1}{sup +0.4}) x 10{sup -6}, {Beta}(B{sup {+-}} {yields} f{sub 2}(1270){pi}{sup {+-}}) = (1.57 {+-} 0.42 {+-} 0.16{sub -0.19}{sup +0.53}) x 10{sup -6}, and {Beta}(B{sup {+-}} {yields} {pi}{sup {+-}}{pi}{sup {+-}}{pi}{sup {-+}} nonresonant) = (5.3 {+-} 0.7 {+-} 0.6{sub -0.5}{sup +1.1}) x 10{sup -6}, where the uncertainties are statistical, systematic, and model-dependent, respectively. Measurements of branching fractions for the modes B{sup {+-}} {yields} {rho}{sup 0}(1450){pi}{sup {+-}} and B{sup {+-}} {yields} f{sub 0}(1370){pi}{sup {+-}} are also presented. They observe no significant direct CP asymmetries for the above modes, and there is no evidence for the decays B{sup {+-}} {yields} f{sub 0}(980){pi}{sup {+-}}, B{sup {+-}} {yields} {chi}{sub c0}{pi}{sup {+-}}, or B{sup {+-}} {yields} {chi}{sub c2}{pi}{sup {+-}}.

  5. An Amplitude Analysis of the Decay B+- -> pi+- pi+- pi-+

    SciTech Connect

    Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; Grauges, E.; Palano, A.; Pappagallo, M.; Pompili, A.; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; Eigen, G.; Ofte, I.; Stugu, B. /Bergen U. /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /Pisa U. /INFN, Pisa /Prairie View A-M /Princeton U. /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Stony Brook /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Vanderbilt U. /Victoria U. /Wisconsin U., Madison /Yale U.

    2005-07-11

    The authors present a Dalitz-plot analysis of charmless B{sup {+-}} decays to the final state {pi}{sup {+-}}{pi}{sup {+-}}{pi}{sup {-+}} using 210 fb{sup -1} of data recorded by the BABAR experiment at {radical}s = 10.58 GeV. We measure the branching fractions {Beta}(B{sup {+-}} {yields} {pi}{sup {+-}}{pi}{sup {+-}}{pi}{sup {-+}}) = (16.2 {+-} 1.2 {+-} 0.9) x 10{sup -6} and {Beta}(B{sup {+-}} {yields} {rho}{sup 0}(770){pi}{sup {+-}}) = (8.8 {+-} 1.0 {+-} 0.6{sub -0.7}{sup +0.1}) x 10{sup -6}. Measurements of branching fractions for the quasi-two-body decays B{sup {+-}} {yields} {rho}{sup 0}(1450){pi}{sup {+-}}, B{sup {+-}} {yields} f{sub 0}(980){pi}{sup {+-}} and B{sup {+-}} f{sub 2}(1270){pi}{sup {+-}} are also presented. They observe no charge asymmetries for the above modes, and there is no evidence for the decays B{sup {+-}} {yields} {chi}{sub c0}{pi}{sup {+-}}, B{sup {+-}} {yields} f{sub 0}(1370){pi}{sup {+-}} and B{sup {+-}} {yields} {sigma}{pi}{sup {+-}}.

  6. NONWATER QUALITY IMPACTS OF CLOSED-CYCLE COOLING SYSTEMS AND THE INTERACTION OF STACK GAS AND COOLING TOWER PLUMES

    EPA Science Inventory

    The report gives results of a literature survey of the nonwater quality impacts of closed-cycle cooling systems. Following discussions of cooling tower and stack gas plumes, interactions of these plumes are considered. For cooling tower plumes, plume types, behavior, salt drift g...

  7. Note: Resonance magnetoelectric interactions in laminate of FeCuNbSiB and multilayer piezoelectric stack for magnetic sensor.

    PubMed

    Li, Jianqiang; Lu, Caijiang; Xu, Changbao; Zhong, Ming

    2015-09-01

    This paper develops a simple miniature magnetoelectric (ME) laminate FeCuNbSiB/PZT-stack made up of magnetostrictive Fe73.5Cu1Nb3Si13.5B9 (FeCuNbSiB) foils and piezoelectric Pb(Zr, Ti)O3 (PZT) multilayer stack vibrator. Resonant ME interactions of FeCuNbSiB/PZT-stack with different layers of FeCuNbSiB foil (L) are investigated in detail. The experimental results show that the ME voltage coefficient reaches maximum value of 141.5 (V/cm Oe) for FeCuNbSiB/PZT-stack with L = 6. The AC-magnetic sensitivities can reach 524.29 mV/Oe and 1.8 mV/Oe under resonance 91.6 kHz and off-resonance 1 kHz, respectively. The FeCuNbSiB/PZT-stack can distinguish small dc-magnetic field of ∼9 nT. The results indicate that the proposed ME composites are very promising for the cheap room-temperature magnetic field sensing technology. PMID:26429496

  8. Note: Resonance magnetoelectric interactions in laminate of FeCuNbSiB and multilayer piezoelectric stack for magnetic sensor

    NASA Astrophysics Data System (ADS)

    Li, Jianqiang; Lu, Caijiang; Xu, Changbao; Zhong, Ming

    2015-09-01

    This paper develops a simple miniature magnetoelectric (ME) laminate FeCuNbSiB/PZT-stack made up of magnetostrictive Fe73.5Cu1Nb3Si13.5B9 (FeCuNbSiB) foils and piezoelectric Pb(Zr, Ti)O3 (PZT) multilayer stack vibrator. Resonant ME interactions of FeCuNbSiB/PZT-stack with different layers of FeCuNbSiB foil (L) are investigated in detail. The experimental results show that the ME voltage coefficient reaches maximum value of 141.5 (V/cm Oe) for FeCuNbSiB/PZT-stack with L = 6. The AC-magnetic sensitivities can reach 524.29 mV/Oe and 1.8 mV/Oe under resonance 91.6 kHz and off-resonance 1 kHz, respectively. The FeCuNbSiB/PZT-stack can distinguish small dc-magnetic field of ˜9 nT. The results indicate that the proposed ME composites are very promising for the cheap room-temperature magnetic field sensing technology.

  9. Control of intramolecular π-π stacking interaction in cationic iridium complexes via fluorination of pendant phenyl rings.

    PubMed

    He, Lei; Ma, Dongxin; Duan, Lian; Wei, Yongge; Qiao, Juan; Zhang, Deqiang; Dong, Guifang; Wang, Liduo; Qiu, Yong

    2012-04-16

    Intramolecular π-π stacking interaction in one kind of phosphorescent cationic iridium complexes has been controlled through fluorination of the pendant phenyl rings on the ancillary ligands. Two blue-green-emitting cationic iridium complexes, [Ir(ppy)(2)(F2phpzpy)]PF(6) (2) and [Ir(ppy)(2)(F5phpzpy)]PF(6) (3), with the pendant phenyl rings on the ancillary ligands substituted with two and five fluorine atoms, respectively, have been synthesized and compared to the parent complex, [Ir(ppy)(2)(phpzpy)]PF(6) (1). Here Hppy is 2-phenylpyridine, F2phpzpy is 2-(1-(3,5-difluorophenyl)-1H-pyrazol-3-yl)pyridine, F5phpzpy is 2-(1-pentafluorophenyl-1H-pyrazol-3-yl)-pyridine, and phpzpy is 2-(1-phenyl-1H-pyrazol-3-yl)pyridine. Single crystal structures reveal that the pendant phenyl rings on the ancillary ligands stack to the phenyl rings of the ppy ligands, with dihedral angles of 21°, 18°, and 5.0° between least-squares planes for complexes 1, 2, and 3, respectively, and centroid-centroid distances of 3.75, 3.65, and 3.52 Å for complexes 1, 2, and 3, respectively, indicating progressively reinforced intramolecular π-π stacking interactions from complexes 1 to 2 and 3. Compared to complex 1, complex 3 with a significantly reinforced intramolecular face-to-face π-π stacking interaction exhibits a significantly enhanced (by 1 order of magnitude) photoluminescent efficiency in solution. Theoretical calculations reveal that in complex 3 it is unfavorable in energy for the pentafluorophenyl ring to swing by a large degree and the intramolecular π-π stacking interaction remains on the lowest triplet state. PMID:22462475

  10. Structure of Musashi1 in a complex with target RNA: the role of aromatic stacking interactions.

    PubMed

    Ohyama, Takako; Nagata, Takashi; Tsuda, Kengo; Kobayashi, Naohiro; Imai, Takao; Okano, Hideyuki; Yamazaki, Toshio; Katahira, Masato

    2012-04-01

    Mammalian Musashi1 (Msi1) is an RNA-binding protein that regulates the translation of target mRNAs, and participates in the maintenance of cell 'stemness' and tumorigenesis. Msi1 reportedly binds to the 3'-untranslated region of mRNA of Numb, which encodes Notch inhibitor, and impedes initiation of its translation by competing with eIF4G for PABP binding, resulting in triggering of Notch signaling. Here, the mechanism by which Msi1 recognizes the target RNA sequence using its Ribonucleoprotein (RNP)-type RNA-binding domains (RBDs), RBD1 and RBD2 has been revealed on identification of the minimal binding RNA for each RBD and determination of the three-dimensional structure of the RBD1:RNA complex. Unique interactions were found for the recognition of the target sequence by Msi1 RBD1: adenine is sandwiched by two phenylalanines and guanine is stacked on the tryptophan in the loop between β1 and α1. The minimal recognition sequences that we have defined for Msi1 RBD1 and RBD2 have actually been found in many Msi1 target mRNAs reported to date. The present study provides molecular clues for understanding the biology involving Musashi family proteins. PMID:22140116

  11. Trinuclear organooxotin assemblies from solvothermal synthesis reaction: Crystal structure, hydrogen bonding and π π stacking interaction

    NASA Astrophysics Data System (ADS)

    Ma, Chunlin; Sun, Junshan; Zhang, Rufen

    2007-05-01

    Two new trinuclear mono-organooxotin(IV) complexes with 2,3,4,5-tetrafluorobenzoic acid and sodium perchlorate of the types: [(SnR) 3(OH)(2,3,4,5-F 4C 6HCO 2) 4 · ClO 4] · [O 2CC 6HF 4](R = PhCH 2, 1; o- F-PhCH 2 for 2), have been solvothermally synthesized and structurally characterized by elemental, IR, 1H, 13C and 119Sn NMR and X-ray crystallography diffraction analyses. Complex 2 is also characterized by X-ray crystallography diffraction analyses. In complex 2, four carboxyl groups and a perchlorate bridged three tin atoms in a cyclohexane chair arrangement and form the basic framework. A hydroxyl group comprises the oxygen components of the stannoxane ring system. In these complexes, weak but significant intramolecular hydrogen bonding and π-π stacking interaction are also shown. These contacts lead to aggregation and supramolecular assembly of complexes 1 and 2 into 1D or 2D framework.

  12. Evidence of a broad structure at an invariant mass of 4.32 GeV/c2 in the reaction e+e- --> pi+pi-psi(2S) measured at BABAR.

    PubMed

    Aubert, B; Barate, R; Bona, M; Boutigny, D; Couderc, F; Karyotakis, Y; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Grauges, E; Palano, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Gill, M S; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; del Amo Sanchez, P; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schroeder, T; Steinke, M; Boyd, J T; Burke, J P; Cottingham, W N; Walker, D; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Kyberd, P; Saleem, M; Sherwood, D J; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Best, D S; Bondioli, M; Bruinsma, M; Chao, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Zhang, L; Hadavand, H K; Hill, E J; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dvoretskii, A; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Ruddick, W O; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Chen, A; Eckhart, E A; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Zeng, Q; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Petzold, A; Spaan, B; Brandt, T; Klose, V; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Grenier, P; Latour, E; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Flack, R L; Nash, J A; Nikolich, M B; Panduro Vazquez, W; Behera, P K; Chai, X; Charles, M J; Mallik, U; Meyer, N T; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gritsan, A V; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Davier, M; Grosdidier, G; Höcker, A; Le Diberder, F; Lepeltier, V; Lutz, A M; Oyanguren, A; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Stocchi, A; Wang, W F; Wormser, G; Cheng, C H; Lange, D J; Wright, D M; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; George, K A; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; Di Lodovico, F; Menges, W; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; Naisbit, M T; Williams, J C; Yi, J I; Chen, C; Hulsbergen, W D; Jawahery, A; Lae, C K; Roberts, D A; Simi, G; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Saremi, S; Staengle, H; Cowan, R; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Kim, H; McLachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Raven, G; Snoek, H L; Jessop, C P; LoSecco, J M; Allmendinger, T; Benelli, G; Gan, K K; Honscheid, K; Hufnagel, D; Jackson, P D; Kagan, H; Kass, R; Rahimi, A M; Ter-Antonyan, R; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; Chauveau, J; Briand, H; David, P

    2007-05-25

    We present a measurement of the cross section of the process e(+)e(-)-->pi(+)pi(-)psi(2S) from threshold up to 8 GeV center-of-mass energy using events containing initial-state radiation, produced at the SLAC PEP-II e(+)e(-) storage rings. The study is based on 298 fb(-1) of data recorded with the BABAR detector. A structure is observed in the cross section not far above threshold, near 4.32 GeV. We also investigate the compatibility of this structure with the Y(4260) previously reported by this experiment. PMID:17677767

  13. The collapse of stacking fault tetrahedra by interactions with gliding dislocations.

    SciTech Connect

    Matsukawa, Yoshitaka; Osetskiy, Yury N; Stocks, George Malcolm; Zinkle, Steven J

    2005-01-01

    The collapse of stacking-fault tetrahedra (SFT) by gliding dislocations was observed in in situ straining experiments in a transmission electron microscope (TEM). A stacking-fault tetrahedron was collapsed by intersection with a gliding perfect dislocation: only the base portion divided by the gliding plane of the dislocation annihilated, while the apex portion remained intact. As a result of analysis on evolution of atom configuration induced by intersection with perfect dislocation in SFT, it was found that an unusual atom configuration inevitably appeared in one of the ledges formed on stacking-fault planes, which is traditionally called I-ledge: the atoms on adjacent (111) planes were overlapping each other. The overlapping configuration provides a strong repulsive force, being a conceivable driving force to induce a chain reaction of atom displacements that collapses the SFT base portion.

  14. The Soil Stack: An Interactive Computer Program Describing Basic Soil Science and Soil Degradation.

    ERIC Educational Resources Information Center

    Cattle, S. R.; And Others

    1995-01-01

    A computer program dealing with numerous aspects of soil degradation has a target audience of high school and university students (16-20 year olds), and is presented in a series of cards grouped together as stacks. Describes use of the software in Australia. (LZ)

  15. Center motions of nonoverlapping condensates coupled by long-range dipolar interaction in bilayer and multilayer stacks

    NASA Astrophysics Data System (ADS)

    Huang, Chao-Chun; Wu, Wen-Chin

    2010-11-01

    We investigate the effect of anisotropic and long-range dipole-dipole interaction (DDI) on the center motions of nonoverlapping Bose-Einstein condensates in bilayer and multilayer stacks. In the bilayer, it is shown analytically that while DDI plays no role in the in-phase modes of center motions of condensates, out-of-phase mode frequency (ωo) depends crucially on the strength of DDI (ad). At the small-ad limit, ωo2(ad)-ωo2(0)∝ad. In the multilayer stack, transverse modes associated with center motions of coupled condensates are found to be optical-phonon-like. At the long-wavelength limit, phonon velocity is proportional to ad.

  16. Energy hyperspace for stacking interaction in AU/AU dinucleotide step: Dispersion-corrected density functional theory study.

    PubMed

    Mukherjee, Sanchita; Kailasam, Senthilkumar; Bansal, Manju; Bhattacharyya, Dhananjay

    2014-01-01

    Double helical structures of DNA and RNA are mostly determined by base pair stacking interactions, which give them the base sequence-directed features, such as small roll values for the purine-pyrimidine steps. Earlier attempts to characterize stacking interactions were mostly restricted to calculations on fiber diffraction geometries or optimized structure using ab initio calculations lacking variation in geometry to comment on rather unusual large roll values observed in AU/AU base pair step in crystal structures of RNA double helices. We have generated stacking energy hyperspace by modeling geometries with variations along the important degrees of freedom, roll, and slide, which were chosen via statistical analysis as maximally sequence dependent. Corresponding energy contours were constructed by several quantum chemical methods including dispersion corrections. This analysis established the most suitable methods for stacked base pair systems despite the limitation imparted by number of atom in a base pair step to employ very high level of theory. All the methods predict negative roll value and near-zero slide to be most favorable for the purine-pyrimidine steps, in agreement with Calladine's steric clash based rule. Successive base pairs in RNA are always linked by sugar-phosphate backbone with C3'-endo sugars and this demands C1'-C1' distance of about 5.4 Å along the chains. Consideration of an energy penalty term for deviation of C1'-C1' distance from the mean value, to the recent DFT-D functionals, specifically ωB97X-D appears to predict reliable energy contour for AU/AU step. Such distance-based penalty improves energy contours for the other purine-pyrimidine sequences also. © 2013 Wiley Periodicals, Inc. Biopolymers 101: 107-120, 2014. PMID:23722519

  17. Dalitz Plot Analyses of B- to D+ Pi- Pi-, B+ to Pi+ Pi- Pi+ and D(S)+ to Pi+ Pi- Pi+ at BaBar

    SciTech Connect

    Dong, Liaoyuan; /Iowa State U.

    2012-04-10

    We report on the Dalitz plot analyses of B{sup -} {yields} D{sup +}{pi}{sup -}{pi}{sup -}, B{sup +} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup +} and D{sub s}{sup +} {yields} {pi}{sup +}{pi}{sup -}{sup +}. The Dalitz plot method and the most recent BABAR results are discussed.

  18. The effect of stacking fault energy on interactions between an edge dislocation and a spherical void by molecular dynamics simulations

    NASA Astrophysics Data System (ADS)

    Asari, K.; Hetland, O. S.; Fujita, S.; Itakura, M.; Okita, T.

    2013-11-01

    Molecular dynamics simulations were conducted using a set of six interatomic potentials for FCC metals that differed only in stacking fault energy (SFE), to clarify the effect of SFE on interactions between a dissociated edge dislocation and a void. There are two different types of interaction mechanism: separate depinning of the individual partial dislocations and almost simultaneous depinning of the combined partial dislocations. The interaction mechanism depends on both the SFE and void size, and changes the absolute value of the critical resolved shear stress (CRSS) and its dependence on the SFE. In the separate depinning case, the CRSS is relatively low and is almost independent of the SFE, while in the simultaneous case, the CRSS is increases with SFE. The void size for which the change in interaction mechanism occurs increases with decreasing SFE.

  19. Growing Ultra-flat Organic Films on Graphene with a Face-on Stacking via Moderate Molecule-Substrate Interaction

    PubMed Central

    Wang, Ti; Kafle, Tika R.; Kattel, Bhupal; Liu, Qingfeng; Wu, Judy; Chan, Wai-Lun

    2016-01-01

    The electronic properties of small molecule organic crystals depend heavily on the molecular orientation. For multi-layer organic photovoltaics, it is desirable for the molecules to have a face-on orientation in order to enhance the out-of-plane transport properties. However, it is challenging to grow well-ordered and smooth films with a face-on stacking on conventional substrates such as metals and oxides. In this work, metal-phthalocyanine molecules is used as a model system to demonstrate that two-dimensional crystals such as graphene can serve as a template for growing high quality, ultra-flat organic films with a face-on orientation. Furthermore, the molecule-substrate interaction is varied systematically from strong to weak interaction regime with the interaction strength characterized by ultrafast electron transfer measurements. We find that in order to achieve the optimum orientation and morphology, the molecule-substrate interaction needs to be strong enough to ensure a face-on stacking while it needs to be weak enough to avoid film roughening. PMID:27356623

  20. Growing Ultra-flat Organic Films on Graphene with a Face-on Stacking via Moderate Molecule-Substrate Interaction

    NASA Astrophysics Data System (ADS)

    Wang, Ti; Kafle, Tika R.; Kattel, Bhupal; Liu, Qingfeng; Wu, Judy; Chan, Wai-Lun

    2016-06-01

    The electronic properties of small molecule organic crystals depend heavily on the molecular orientation. For multi-layer organic photovoltaics, it is desirable for the molecules to have a face-on orientation in order to enhance the out-of-plane transport properties. However, it is challenging to grow well-ordered and smooth films with a face-on stacking on conventional substrates such as metals and oxides. In this work, metal-phthalocyanine molecules is used as a model system to demonstrate that two-dimensional crystals such as graphene can serve as a template for growing high quality, ultra-flat organic films with a face-on orientation. Furthermore, the molecule-substrate interaction is varied systematically from strong to weak interaction regime with the interaction strength characterized by ultrafast electron transfer measurements. We find that in order to achieve the optimum orientation and morphology, the molecule-substrate interaction needs to be strong enough to ensure a face-on stacking while it needs to be weak enough to avoid film roughening.

  1. Growing Ultra-flat Organic Films on Graphene with a Face-on Stacking via Moderate Molecule-Substrate Interaction.

    PubMed

    Wang, Ti; Kafle, Tika R; Kattel, Bhupal; Liu, Qingfeng; Wu, Judy; Chan, Wai-Lun

    2016-01-01

    The electronic properties of small molecule organic crystals depend heavily on the molecular orientation. For multi-layer organic photovoltaics, it is desirable for the molecules to have a face-on orientation in order to enhance the out-of-plane transport properties. However, it is challenging to grow well-ordered and smooth films with a face-on stacking on conventional substrates such as metals and oxides. In this work, metal-phthalocyanine molecules is used as a model system to demonstrate that two-dimensional crystals such as graphene can serve as a template for growing high quality, ultra-flat organic films with a face-on orientation. Furthermore, the molecule-substrate interaction is varied systematically from strong to weak interaction regime with the interaction strength characterized by ultrafast electron transfer measurements. We find that in order to achieve the optimum orientation and morphology, the molecule-substrate interaction needs to be strong enough to ensure a face-on stacking while it needs to be weak enough to avoid film roughening. PMID:27356623

  2. Isomorphous dichloro- and dibromo(2-methyl-2-phenylpropyl)phenylstannane, both displaying the same intramolecular pi-pi interaction at 120 K.

    PubMed

    Bomfim, Joäo A S; Filgueiras, Carlos A L; Howie, R Alan; Skakle, Janet M S; Wardell, James L

    2003-12-01

    The title compounds, dichloro- and dibromoneophylphenyltin, [SnCl(2)(C(6)H(5))(C(10)H(13))] and [SnBr(2)(C(6)H(5))(C(10)H(13))], respectively, are remarkable for the 'U' shape of the molecules, whereby the two phenyl groups are brought face-to-face in an arrangement that permits intermolecular C-H.pi bonds to connect the molecules into layers parallel to (100). Intermolecular Sn-halide bonds are notably absent from the structures. PMID:14671349

  3. Organic pi-stacked materials for electronic applications: Synthesis, characterizations, modeling and devices

    NASA Astrophysics Data System (ADS)

    Cao, Jie

    structure, a pi-stack forms a tilted staircase motif with strong pi-pi overlap within the stack. EBTz-COOH shows a dimer-like packing motif similar to the dimer, (EBTz)2 due to the introduction of H-bonding. Semi-empirical MO calculations (ZINDO/S) were used to evaluate interchain interactions between molecules in their experimentally determined positions in the solid-state. The results show that the strong interchain interactions along the pi-stacking direction may exceed that of herringbone structures (e.g. pentacene). The ZINDO/S method can also be used to study the Davydov splitting and the exciton band structure in the solid-state.

  4. Interaction of small mobile stacking fault tetrahedra with free surfaces, dislocations, and interfaces in Cu and Cu-Nb

    NASA Astrophysics Data System (ADS)

    Martínez, Enrique; Uberuaga, Blas P.; Beyerlein, Irene J.

    2016-02-01

    The presence of stacking fault tetrahedra (SFTs) in face-centered-cubic metals substantially modifies the material response to external loading. These defects are extremely stable with increasing energetic stability as they grow in size. At the sizes visible within a transmission electron microscope, they appear nearly immobile. We have recently shown that these defects might indeed migrate, with defective SFTs exhibiting particularly high mobilities. In this paper, using molecular dynamics, we show how mobile SFTs interact with various types of extended defects, including free surfaces, dislocations, and interfaces in Cu and Cu-Nb systems. We observe a direct relation between the energetics of a single vacancy interacting with each external defect and the propensity for the SFT to be absorbed. Finally, using mesoscale modeling, we show how the fact that SFTs can migrate influences the system evolution and potentially important observables of interest such as the void denuded zones around defect sinks.

  5. Stacking interactions in RNA and DNA: Roll-slide energy hyperspace for ten unique dinucleotide steps.

    PubMed

    Mukherjee, Sanchita; Kailasam, Senthilkumar; Bansal, Manju; Bhattacharyya, Dhananjay

    2015-03-01

    Understanding dinucleotide sequence directed structures of nuleic acids and their variability from experimental observation remained ineffective due to unavailability of statistically meaningful data. We have attempted to understand this from energy scan along twist, roll, and slide degrees of freedom which are mostly dependent on dinucleotide sequence using ab initio density functional theory. We have carried out stacking energy analysis in these dinucleotide parameter phase space for all ten unique dinucleotide steps in DNA and RNA using DFT-D by ωB97X-D/6-31G(2d,2p), which appears to satisfactorily explain conformational preferences for AU/AU step in our recent study. We show that values of roll, slide, and twist of most of the dinucleotide sequences in crystal structures fall in the low energy region. The minimum energy regions with large twist values are associated with the roll and slide values of B-DNA, whereas, smaller twist values correspond to higher stability to RNA and A-DNA like conformations. Incorporation of solvent effect by CPCM method could explain the preference shown by some sequences to occur in B-DNA or A-DNA conformations. Conformational preference of BII sub-state in B-DNA is preferentially displayed mainly by pyrimidine-purine steps and partly by purine-purine steps. The purine-pyrimidine steps show largest effect of 5-methyl group of thymine in stacking energy and the introduction of solvent reduces this effect significantly. These predicted structures and variabilities can explain the effect of sequence on DNA and RNA functionality. PMID:25257334

  6. Measurement of cos2beta in B;{0}-->D;{(*)}h;{0} decays with a time-dependent Dalitz plot analysis of D-->K_{s};{0}pi;{+}pi;{-}.

    PubMed

    Aubert, B; Bona, M; Boutigny, D; Karyotakis, Y; Lees, J P; Poireau, V; Prudent, X; Tisserand, V; Zghiche, A; Tico, J Garra; Grauges, E; Lopez, L; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Pegna, D Lopes; Lynch, G; Mir, L M; Orimoto, T J; Osipenkov, I L; Ronan, M T; Tackmann, K; Tanabe, T; Wenzel, W A; Del Amo Sanchez, P; Hawkes, C M; Watson, A T; Koch, H; Schroeder, T; Walker, D; Asgeirsson, D J; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Khan, A; Saleem, M; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Liu, F; Long, O; Shen, B C; Vitug, G M; Zhang, L; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Schalk, T; Schumm, B A; Seiden, A; Wilson, M G; Winstrom, L O; Chen, E; Cheng, C H; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Gabareen, A M; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Klose, V; Kobel, M J; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Lombardo, V; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Watson, J E; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Franchini, P; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Santoro, V; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Dauncey, P D; Flack, R L; Nash, J A; Vazquez, W Panduro; Tibbetts, M; Behera, P K; Chai, X; Charles, M J; Mallik, U; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Lae, C K; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Béquilleux, J; D'Orazio, A; Davier, M; Grosdidier, G; Höcker, A; Lepeltier, V; Le Diberder, F; Lutz, A M; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wang, W F; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Chavez, C A; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; George, K A; Di Lodovico, F; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Paramesvaran, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Bailey, D; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Salvati, E; Saremi, S; Cowan, R; Dujmic, D; Fisher, P H; Koeneke, K; Sciolla, G; Spitznagel, M; Taylor, F; Yamamoto, R K; Zhao, M; Zheng, Y; McLachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; De Nardo, G; Fabozzi, F; Lista, L; Monorchio, D; Sciacca, C; Baak, M A; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; Losecco, J M; Benelli, G; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Sekula, S J; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gagliardi, N; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Ben-Haim, E; Briand, H; Calderini, G; Chauveau, J; David, P; Del Buono, L; de la Vaissière, Ch; Hamon, O; Leruste, Ph; Malclès, J; Ocariz, J; Perez, A; Prendki, J; Gladney, L; Biasini, M; Covarelli, R; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Carpinelli, M; Cenci, R; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Mazur, M A; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Biesiada, J; Elmer, P; Lau, Y P; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Baracchini, E; Bellini, F; Cavoto, G; Del Re, D; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Gioi, L Li; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Renga, F; Voena, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Castelli, G; Franek, B; Olaiya, E O; Roethel, W; Wilson, F F; Emery, S; Escalier, M; Gaidot, A; Ganzhur, S F; de Monchenault, G Hamel; Kozanecki, W; Vasseur, G; Yèche, Ch; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; White, R M; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Bechtle, P; Claus, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Glanzman, T; Gowdy, S J; Graham, M T; Grenier, P; Hast, C; Innes, W R; Kaminski, J; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Luitz, S; Luth, V; Lynch, H L; Macfarlane, D B; Marsiske, H; Messner, R; Muller, D R; O'Grady, C P; Ofte, I; Perazzo, A; Perl, M; Pulliam, T; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; Wagner, A P; Weaver, M; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Yi, K; Young, C C; Ziegler, V; Burchat, P R; Edwards, A J; Majewski, S A; Miyashita, T S; Petersen, B A; Wilden, L; Ahmed, S; Alam, M S; Bula, R; Ernst, J A; Jain, V; Pan, B; Saeed, M A; Wappler, F R; Zain, S B; Krishnamurthy, M; Spanier, S M; Eckmann, R; Ritchie, J L; Ruland, A M; Schilling, C J; Schwitters, R F; Izen, J M; Lou, X C; Ye, S; Bianchi, F; Gallo, F; Gamba, D; Pelliccioni, M; Bomben, M; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martinez-Vidal, F; Milanes, D A; Oyanguren, A; Albert, J; Banerjee, Sw; Bhuyan, B; Hamano, K; Kowalewski, R; Nugent, I M; Roney, J M; Sobie, R J; Harrison, P F; Ilic, J; Latham, T E; Mohanty, G B; Band, H R; Chen, X; Dasu, S; Flood, K T; Hollar, J J; Kutter, P E; Pan, Y; Pierini, M; Prepost, R; Wu, S L; Neal, H

    2007-12-01

    We study the time-dependent Dalitz plot of D-->K_{S};{0}pi;{+}pi;{-} in B;{0}-->D;{(*)}h;{0} decays, where h;{0} is a pi;{0}, eta, eta;{'}, or omega meson and D;{*}-->Dpi;{0}, using a data sample of 383x10;{6} Upsilon(4S)-->BB[over ] decays collected with the BABAR detector. We determine cos2beta=0.42+/-0.49+/-0.09+/-0.13, sin2beta=0.29+/-0.34+/-0.03+/-0.05, and |lambda|=1.01+/-0.08+/-0.02, where the first error is statistical, the second is the experimental systematic uncertainty, and the third, where given, is the Dalitz model uncertainty. Assuming the world average value for sin2beta and |lambda|=1, cos2beta>0 is preferred over cos2beta<0 at 86% confidence level. PMID:18233357

  7. Evidence of π-stacking Interactions in the Self-Assembly of hIAPP22–29†

    PubMed Central

    Profit, Adam A.; Felsen, Valentina; Chinwong, Justina; Mojica, Elmer-Rico E.; Desamero, Ruel Z. B.

    2012-01-01

    The role aromatic amino acids play in the formation of amyloid is a subject of controversy. In an effort to clarify the contribution of aromaticity to the self-assembly of hIAPP22–29, peptide analogs containing electron donating groups (EDGs) or electron withdrawing groups (EWGs) as substituents on the aromatic ring of Phe-23 at the para position have been synthesized and characterized using turbidity measurements in conjunction with Raman, and fluorescence spectroscopy. Results indicate the incorporation of EDGs on the aromatic ring of Phe-23 virtually abolish the ability of hIAPP22–29 to form amyloid. Peptides containing EWGs were still capable of forming aggregates. These aggregates were found to be rich in β-sheet secondary structure. TEM images of the aggregates confirm the presence of amyloid fibrils. The observed difference in amyloidogenic propensity between peptides containing EDGs and those with EWGs appears not to be based on differences in peptide hydrophobicity. Fluorescence and Raman spectroscopic investigations reveal that the environment surrounding the aromatic ring becomes more hydrophobic and ordered upon aggregation. Furthermore, Raman measurements of peptide analogs containing EWGs, conclusively demonstrate a distinct downshift in the -C=C- ring mode (ca. 1600 cm−1) upon aggregation that has previously been shown to be indicative of π-stacking. While previous work has demonstrated that π-stacking is not an absolute requirement for fibrillization, our findings indicate that Phe-23 also contributes to fibril formation through π-stacking interactions and that it is not only the hydrophobic nature of this residue that is relevant in the self-assembly of hIAPP22–29. PMID:23229921

  8. Stacking Interactions between Carbohydrate and Protein Quantified by Combination of Theoretical and Experimental Methods

    PubMed Central

    Nečasová, Ivona; Mishra, Sushil Kumar; Komárek, Jan; Koča, Jaroslav

    2012-01-01

    Carbohydrate – receptor interactions are an integral part of biological events. They play an important role in many cellular processes, such as cell-cell adhesion, cell differentiation and in-cell signaling. Carbohydrates can interact with a receptor by using several types of intermolecular interactions. One of the most important is the interaction of a carbohydrate's apolar part with aromatic amino acid residues, known as dispersion interaction or CH/π interaction. In the study presented here, we attempted for the first time to quantify how the CH/π interaction contributes to a more general carbohydrate - protein interaction. We used a combined experimental approach, creating single and double point mutants with high level computational methods, and applied both to Ralstonia solanacearum (RSL) lectin complexes with α-l-Me-fucoside. Experimentally measured binding affinities were compared with computed carbohydrate-aromatic amino acid residue interaction energies. Experimental binding affinities for the RSL wild type, phenylalanine and alanine mutants were −8.5, −7.1 and −4.1 kcal.mol−1, respectively. These affinities agree with the computed dispersion interaction energy between carbohydrate and aromatic amino acid residues for RSL wild type and phenylalanine, with values −8.8, −7.9 kcal.mol−1, excluding the alanine mutant where the interaction energy was −0.9 kcal.mol−1. Molecular dynamics simulations show that discrepancy can be caused by creation of a new hydrogen bond between the α-l-Me-fucoside and RSL. Observed results suggest that in this and similar cases the carbohydrate-receptor interaction can be driven mainly by a dispersion interaction. PMID:23056230

  9. Van der Waals stacks of few-layer h-AlN with graphene: an ab initio study of structural, interaction and electronic properties

    NASA Astrophysics Data System (ADS)

    dos Santos, Renato B.; de Brito Mota, F.; Rivelino, R.; Kakanakova-Georgieva, A.; Gueorguiev, G. K.

    2016-04-01

    Graphite-like hexagonal AlN (h-AlN) multilayers have been experimentally manifested and theoretically modeled. The development of any functional electronics applications of h-AlN would most certainly require its integration with other layered materials, particularly graphene. Here, by employing vdW-corrected density functional theory calculations, we investigate structure, interaction energy, and electronic properties of van der Waals stacking sequences of few-layer h-AlN with graphene. We find that the presence of a template such as graphene induces enough interlayer charge separation in h-AlN, favoring a graphite-like stacking formation. We also find that the interface dipole, calculated per unit cell of the stacks, tends to increase with the number of stacked layers of h-AlN and graphene.

  10. Comprehensive molecular dynamics simulations of the stacking fault tetrahedron interacting with a mixed dislocation at elevated temperature

    NASA Astrophysics Data System (ADS)

    Fan, Haidong; Wang, Qingyuan; Ouyang, Chaojun

    2015-10-01

    The defect-free channels were frequently observed in irradiated materials, i.e. copper, as a result of the stacking fault tetrahedron (SFT) interactions with dislocations. However, the underlying mechanisms for this process are still unclear to date. To address them, a comprehensive study on the interactions between SFTs and mixed dislocations was performed using molecular dynamics simulations. In particular, eight interaction geometries were considered, in terms of the dislocation Burgers vector directions, dislocation gliding directions and intersection positions on SFT. Various interaction outcomes were revealed after dislocation detachment. (1) SFT is fully absorbed through the transformation into Lomer dislocations, and subsequently moves out of free surfaces along the dislocation. (2) SFT is partially absorbed with the absorbed SFT base moving out of free surfaces along the dislocation. (3) SFT is not absorbed but sheared with ledges left on the SFT faces. (4) SFT is unaffected by the mixed dislocation. The current simulations, especially the full SFT absorption, provide important insights into the forming mechanisms of defect-free channels in irradiated materials.

  11. Non-covalent stacking interactions directing the structural and photophysical features of mono- and dinuclear cyclometalated palladium(ii) complexes.

    PubMed

    Santana, M D; López-Banet, L; Sánchez, G; Pérez, J; Pérez, E; García, L; Serrano, J L; Espinosa, A

    2016-05-17

    The solution/solid state luminescence properties of selected orthometalated palladium complexes have been investigated in parallel with the relevant structural information provided by their X-ray crystal structures and theoretical calculations. Two cyclometalated backbones with different stacking abilities and a selection of bridging O^O, O^N or N^S ligands comprise the series under study, [{Pd(μ-L) (C^N)}2] (C^N = N-phenylpyrazole (Phpz) ; N-benzylideneaniline (Bza) ; L = acetate (Aco) , succinimidate (succ) , phthalimidate (phthal) , 1-methylimidazoline-2 thionate (Smeimid) ), completed with mononuclear [Pd(C^N)(N-pClPhsal)] (N-pClPhsal = chlorophenylsalycilaldiminate) complexes. New compounds , and were synthesized and the X-ray structures of , , , and have been elucidated in order to examine and compare solid-state Pd(C^N)-Pd(C^N) and ligand-ligand interactions with the rest of the series. The molecular structures of the complexes reveal intramolecular PdPd distances between 2.842 and 2.999 Å and π-π and C-Hπ interactions. All complexes studied show emission in the solid state at room temperature and a relationship is observed between emission energy, the nature of the lowest energy excited state, and metal-metal interactions. DFT calculations are undertaken to gain insight into the relationship between the structure and photophysical properties of the complexes. PMID:27137832

  12. π-Stacking, C-H/π, and halogen bonding interactions in bromobenzene and mixed bromobenzene-benzene clusters.

    PubMed

    Reid, Scott A; Nyambo, Silver; Muzangwa, Lloyd; Uhler, Brandon

    2013-12-19

    Noncovalent interactions play an important role in many chemical and biochemical processes. Building upon our recent study of the homoclusters of chlorobenzene, where π-π stacking and CH/π interactions were identified as the most important binding motifs, in this work we present a study of bromobenzene (PhBr) and mixed bromobenzene-benzene clusters. Electronic spectra in the region of the PhBr monomer S0-S1 (ππ*) transition were obtained using resonant two-photon ionization (R2PI) methods combined with time-of-flight mass analysis. As previously found for related systems, the PhBr cluster spectra show a broad feature whose center is red-shifted from the monomer absorption, and electronic structure calculations indicate the presence of multiple isomers and Franck-Condon activity in low-frequency intermolecular modes. Calculations at the M06-2X/aug-cc-pVDZ level find in total eight minimum energy structures for the PhBr dimer: four π-stacked structures differing in the relative orientation of the Br atoms (denoted D1-D4), one T-shaped structure (D5), and three halogen bonded structures (D6-D8). The calculated binding energies of these complexes, corrected for basis set superposition error (BSSE) and zero-point energy (ZPE), are in the range of -6 to -24 kJ/mol. Time-dependent density functional theory (TDDFT) calculations predict that these isomers absorb over a range that is roughly consistent with the breadth of the experimental spectrum. To examine the influence of dipole-dipole interaction, R2PI spectra were also obtained for the mixed PhBr···benzene dimer, where the spectral congestion is reduced and clear vibrational structure is observed. This structure is well-simulated by Franck-Condon calculations that incorporate the lowest frequency intermolecular modes. Calculations find four minimum energy structures for the mixed dimer and predict that the binding energy of the global minimum is reduced by ~30% relative to the global minimum PhBr dimer

  13. Equatorial π-stacking interactions in diruthenium (II,III) tetracarboxylate complexes containing extended π-systems

    NASA Astrophysics Data System (ADS)

    O'Rourke, Natasha F.; Ronaldson, Michael; Stanley Cameron, T.; Wang, Ruiyao; Aquino, Manuel A. S.

    2013-11-01

    The synthesis of three new valent-averaged tetracarboxylatodiruthenium (II,III) complexes, [Ru2(1-naphthylacetate)4(H2O)2](PF6)ṡ4THF, 1ṡ4THF, [Ru2(2-naphthoate)4(THF)2](PF6)ṡ3THF, 2ṡ3THF, and [Ru2(coumarin-3-carboxylate)4(MeOH)2](PF6)ṡMeOHṡH2O, 3ṡMeOHṡH2O, was accomplished using a well documented carboxylate exchange reaction. All three complexes were thoroughly characterized using infrared and UV-Vis spectroscopies, elemental analysis and X-ray diffraction. Due to the extended π-systems present, two of the complexes, 2ṡ3THF and 3ṡMeOHṡH2O, display extensive π-stacking in two dimensions, with similar interactions notably absent in 1ṡ4THF due to the perpendicular orientation of the naphthyl rings. Modest H-bonding is seen in complexes 1ṡ4THF and 3ṡMeOHṡH2O. As these types of complexes are noted secondary building units (SBU's) in the construction of metal-organic frameworks (MOF's), the significance of these interactions in stabilizing even larger, supramolecular structures, are noted.

  14. Simultaneous observations of aerosol–cloud–albedo interactions with three stacked unmanned aerial vehicles

    PubMed Central

    Roberts, G. C.; Ramana, M. V.; Corrigan, C.; Kim, D.; Ramanathan, V.

    2008-01-01

    Aerosol impacts on climate change are still poorly understood, in part, because the few observations and methods for detecting their effects are not well established. For the first time, the enhancement in cloud albedo is directly measured on a cloud-by-cloud basis and linked to increasing aerosol concentrations by using multiple autonomous unmanned aerial vehicles to simultaneously observe the cloud microphysics, vertical aerosol distribution, and associated solar radiative fluxes. In the presence of long-range transport of dust and anthropogenic pollution, the trade cumuli have higher droplet concentrations and are on average brighter. Our observations suggest a higher sensitivity of radiative forcing by trade cumuli to increases in cloud droplet concentrations than previously reported owing to a constrained droplet radius such that increases in droplet concentrations also increase cloud liquid water content. This aerosol-cloud forcing efficiency is as much as −60 W m−2 per 100% percent cloud fraction for a doubling of droplet concentrations and associated increase of liquid water content. Finally, we develop a strategy for detecting aerosol–cloud interactions based on a nondimensional scaling analysis that relates the contribution of single clouds to albedo measurements and illustrates the significance of characterizing cloud morphology in resolving radiometric measurements. This study demonstrates that aerosol–cloud–albedo interactions can be directly observed by simultaneous observations below, in, and above the clouds. PMID:18499803

  15. Simultaneous observations of aerosol-cloud-albedo interactions with three stacked unmanned aerial vehicles.

    PubMed

    Roberts, G C; Ramana, M V; Corrigan, C; Kim, D; Ramanathan, V

    2008-05-27

    Aerosol impacts on climate change are still poorly understood, in part, because the few observations and methods for detecting their effects are not well established. For the first time, the enhancement in cloud albedo is directly measured on a cloud-by-cloud basis and linked to increasing aerosol concentrations by using multiple autonomous unmanned aerial vehicles to simultaneously observe the cloud microphysics, vertical aerosol distribution, and associated solar radiative fluxes. In the presence of long-range transport of dust and anthropogenic pollution, the trade cumuli have higher droplet concentrations and are on average brighter. Our observations suggest a higher sensitivity of radiative forcing by trade cumuli to increases in cloud droplet concentrations than previously reported owing to a constrained droplet radius such that increases in droplet concentrations also increase cloud liquid water content. This aerosol-cloud forcing efficiency is as much as -60 W m(-2) per 100% percent cloud fraction for a doubling of droplet concentrations and associated increase of liquid water content. Finally, we develop a strategy for detecting aerosol-cloud interactions based on a nondimensional scaling analysis that relates the contribution of single clouds to albedo measurements and illustrates the significance of characterizing cloud morphology in resolving radiometric measurements. This study demonstrates that aerosol-cloud-albedo interactions can be directly observed by simultaneous observations below, in, and above the clouds. PMID:18499803

  16. Conformational Preferences of π-π Stacking Between Ligand and Protein, Analysis Derived from Crystal Structure Data Geometric Preference of π-π Interaction.

    PubMed

    Zhao, Yuan; Li, Jue; Gu, Hui; Wei, Dongqing; Xu, Yao-Chang; Fu, Wei; Yu, Zhengtian

    2015-09-01

    π-π Interaction is a direct attractive non-covalent interaction between aromatic moieties, playing an important role in DNA stabilization, drug intercalation, etc. Aromatic rings interact through several different conformations including face-to-face, T-shaped, and offset stacked conformation. Previous quantum calculations indicated that T-shaped and offset stacked conformations are preferred for their smaller electron repulsions. However, substitution group on aromatic ring could have a great impact on π-π interaction by changing electron repulsion force between two rings. To investigate π-π interaction between ligand and aromatic side chain of protein, Brookhaven Protein Data Bank was analyzed. We extracted isolated dimer pairs with the aim of excluding multiple π-π stacking effects and found that T-shaped conformation is prevalent among aromatic interaction between phenyl ring of ligand and protein, which corresponds with the phenomenon of Phe-Phe interactions in small peptide. Specifically, for the non-substitution model, both Phe-Phe and Phenyl-Phe exhibit a favored T-shaped conformation whose dihedral angle is around 50°-70° and centroid distance is between 5.0 and 5.6 Å. However, it could be changed by substituent effect. The hydroxyl group could contact in the case of Tyr-Tyr pairs, while they point away from phenyl plane in Phe-Tyr pairs. PMID:26370211

  17. Mesoscopic model parametrization of hydrogen bonds and stacking interactions of RNA from melting temperatures

    PubMed Central

    Weber, Gerald

    2013-01-01

    Information about molecular interactions in DNA can be obtained from experimental melting temperature data by using mesoscopic statistical physics models. Here, we extend the technique to RNA and show that the new parameters correctly reproduce known properties such as the stronger hydrogen bonds of AU base pairs. We also were able to calculate a complete set of elastic constants for all 10 irreducible combinations of nearest neighbours (NNs). We believe that this is particularly useful as experimentally derived information about RNA elasticity is relatively scarce. The melting temperature prediction using the present model improves over those from traditional NN model, providing thus an alternative way to calculate these temperatures for RNA. Additionally, we calculated the site-dependent base pair oscillation to explain why RNA shows larger oscillation amplitudes despite having stronger AU hydrogen bonds. PMID:23087379

  18. Application of diffusion Monte Carlo to materials dominated by van der Waals interactions

    SciTech Connect

    Benali, Anouar; Shulenburger, Luke; Romero, Nichols; Kim, Jeongnim; Von Lilienfeld, Anatole

    2014-01-01

    Van der Waals forces are notoriously difficult to account for from first principles. We perform extensive calculation to assess the usefulness and validity of diffusion quantum Monte Carlo when applied to van der Waals forces. We present results for noble gas solids and clusters - archetypical van der Waals dominated assemblies, as well as a relevant pi-pi stacking supramolecular complex: DNA + intercalating anti-cancer drug Ellipticine.

  19. Application of Diffusion Monte Carlo to Materials Dominated by van der Waals Interactions

    DOE PAGESBeta

    Benali, Anouar; Shulenburger, Luke; Romero, Nichols A.; Kim, Jeongnim; von Lilienfeld, O. Anatole

    2014-06-12

    Van der Waals forces are notoriously difficult to account for from first principles. We perform extensive calculation to assess the usefulness and validity of diffusion quantum Monte Carlo when applied to van der Waals forces. We present results for noble gas solids and clusters - archetypical van der Waals dominated assemblies, as well as a relevant pi-pi stacking supramolecular complex: DNA + intercalating anti-cancer drug Ellipticine.

  20. Light-emitting self-assembled peptide nucleic acids exhibit both stacking interactions and Watson-Crick base pairing

    NASA Astrophysics Data System (ADS)

    Berger, Or; Adler-Abramovich, Lihi; Levy-Sakin, Michal; Grunwald, Assaf; Liebes-Peer, Yael; Bachar, Mor; Buzhansky, Ludmila; Mossou, Estelle; Forsyth, V. Trevor; Schwartz, Tal; Ebenstein, Yuval; Frolow, Felix; Shimon, Linda J. W.; Patolsky, Fernando; Gazit, Ehud

    2015-05-01

    The two main branches of bionanotechnology involve the self-assembly of either peptides or DNA. Peptide scaffolds offer chemical versatility, architectural flexibility and structural complexity, but they lack the precise base pairing and molecular recognition available with nucleic acid assemblies. Here, inspired by the ability of aromatic dipeptides to form ordered nanostructures with unique physical properties, we explore the assembly of peptide nucleic acids (PNAs), which are short DNA mimics that have an amide backbone. All 16 combinations of the very short di-PNA building blocks were synthesized and assayed for their ability to self-associate. Only three guanine-containing di-PNAs—CG, GC and GG—could form ordered assemblies, as observed by electron microscopy, and these di-PNAs efficiently assembled into discrete architectures within a few minutes. The X-ray crystal structure of the GC di-PNA showed the occurrence of both stacking interactions and Watson-Crick base pairing. The assemblies were also found to exhibit optical properties including voltage-dependent electroluminescence and wide-range excitation-dependent fluorescence in the visible region.

  1. Effects of Low-k Stack Structure on Performance of Complementary Metal Oxide Semiconductor Devices and Chip Package Interaction Failure

    NASA Astrophysics Data System (ADS)

    Tagami, Masayoshi; Inoue, Naoya; Ueki, Makoto; Narihiro, Mitsuru; Tada, Munehiro; Yamamoto, Hironori; Ito, Fuminori; Furutake, Naoya; Saito, Shinobu; Onodera, Takahiro; Takeuchi, Tsuneo; Hayashi, Yoshihiro

    2012-09-01

    Low capacitance and highly reliable Cu dual-damascene (DD) interconnects have been developed with self-organized “seamless low-k SiOCH stacks” (SEALS) structure. A carbon-rich sub-nano porous SiOCH (k=2.5) was directly stacked on an oxygen-rich porous SiOCH (k=2.7) in the SEALS structure, without a hard-mask (HM) and etch-stop (ES) layer of SiO2. The effective k-value (keff) of the Cu DD interconnect including the SiCN capping layer (k=4.9) was reduced to 2.9 compared to 3.4 on a conventional hybrid structure with SiO2-HM and ES, which had been used in 65-nm-node mass production. The interconnect delay of a 45-nm-node complementary metal oxide semiconductor (CMOS) ring oscillator (RO) was reduced by 15% referring to that of the conventional hybrid structure. Interconnect reliabilities, such as the interline time dependent dielectric breakdown (TDDB) and thermal cycles, were unchanged from those of the conventional hybrid interconnects. No failure was detected for chip package interaction (CPI) during reliability tests in a plastic ball grid array (PBGA) package. SEALS is a promising structure for scaled down ultra large scale integrations (ULSIs) for highly reliable and high speed operation, and low power consumption.

  2. Observation of a J{sup PC}=1{sup -+} Exotic Resonance in Diffractive Dissociation of 190 GeV/c {pi}{sup -} into {pi}{sup -{pi}-{pi}+}

    SciTech Connect

    Alekseev, M. G.; Colantoni, M.; Denisov, O. Yu.; Maggiora, A.; Alexakhin, V. Yu.; Alexeev, G. D.; Efremov, A.; Finger, M. Jr.; Gavrichtchouk, O. P.; Gushterski, R.; Guskov, A.; Ivanov, O.; Ivanshin, Yu.; Komissarov, E. V.; Kroumchtein, Z. V.; Maximov, A. N.; Nagaytsev, A.; Olshevsky, A. G.; Perevalova, E.; Peshekhonov, D. V.

    2010-06-18

    The COMPASS experiment at the CERN SPS has studied the diffractive dissociation of negative pions into the {pi}{sup -{pi}-{pi}+} final state using a 190 GeV/c pion beam hitting a lead target. A partial wave analysis has been performed on a sample of 420 000 events taken at values of the squared 4-momentum transfer t{sup '} between 0.1 and 1 GeV{sup 2}/c{sup 2}. The well-known resonances a{sub 1}(1260), a{sub 2}(1320), and {pi}{sub 2}(1670) are clearly observed. In addition, the data show a significant natural-parity exchange production of a resonance with spin-exotic quantum numbers J{sup PC}=1{sup -+} at 1.66 GeV/c{sup 2} decaying to {rho}{pi}. The resonant nature of this wave is evident from the mass-dependent phase differences to the J{sup PC}=2{sup -+} and 1{sup ++} waves. From a mass-dependent fit a resonance mass of (1660{+-}10{sub -64}{sup +0}) MeV/c{sup 2} and a width of (269{+-}21{sub -64}{sup +42}) MeV/c{sup 2} are deduced, with an intensity of (1.7{+-}0.2)% of the total intensity.

  3. Branching fractions and CP asymmetries in B0-->pi0pi0, B+-->pi+pi0, and B+-->K+pi0 decays and isospin analysis of the B-->pipi system.

    PubMed

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

    2005-05-13

    Based on a sample of 227 x 10(6) BB pairs collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC, we measure the branching fraction B(B0-->pi(0)pi(0))=(1.17+/-0.32+/-0.10)x10(-6), and the asymmetry Cpi(0)(pi(0))=-0.12+/-0.56+/-0.06. The B0-->pi(0)pi(0) signal has a significance of 5.0 sigma. We also measure B(B+-->pi(+)pi(0))=(5.8+/-0.6+/-0.4)x10(-6), B(B+-->K+pi(0))=(12.0+/-0.7+/-0.6)x10(-6), and the charge asymmetries Api(+)(pi(0))=-0.01+/-0.10+/-0.02 and AK+(pi(0))=0.06+/-0.06+/-0.01. Using isospin relations, we find an upper bound on the angle difference |alpha-alpha(eff)| of 35 degrees at the 90% C.L. PMID:15904359

  4. Stack filters

    NASA Astrophysics Data System (ADS)

    Wendt, P. D.; Coyle, E. J.; Gallagher, N. C., Jr.

    1986-08-01

    A large class of easily implemented nonlinear filters called stack filters are discussed which includes the rank order operators in addition to the compositions of morphological operators. Techniques similar to those used to determine the root signal behavior of median filters are employed to study the convergence properties of the filters, and necessary conditions for a stack filter to preserve monotone regions or edges in signals, and the output distribution of the filters, are obtained. Among the stack filters of window width three are found asymmetric median filters in which one removes only positive going edges, the other removes only negative going edges, while the median filter removes impulses of both signs.

  5. Influence of Secondary Interactions at Graphene-Based Surfaces on the Dynamic and Mechanical Properties in Nanostructured Systems

    NASA Astrophysics Data System (ADS)

    Palmeri, Marc J.

    Graphene, a single atom thick sheet of densely packed carbon atoms, has gained significant interest in nanostructured materials because of its exceptional mechanical, electrical, thermal, and optical properties. Because graphene nanosheets and graphene-based nanoparticles present enormous surface areas relative to their volume, interfacial interactions at graphene-based surfaces yield a significant impact on the properties of nanostructured systems. In this dissertation, secondary interactions (e.g., pi-pi interactions and hydrogen-bonding) at graphene-based surfaces in composite systems and freestanding nanoparticle films were studied, with a focus on their influence over mechanical and dynamic properties. In polymer nanocomposite systems containing carbon nanotubes, the region of altered chain dynamics near nanotube surfaces was examined as a function of crosslink density by dynamic scanning calorimetry. Three mechanisms of altered dynamics were postulated in crosslinked systems, with diminished percolation of these effects at increasing crosslink densities due to restrictions in the length scale of chain rearrangements. In-depth fracture analysis of a polymer nanocomposite containing carbon nanofibers with a stacked-cup structure pointed to the first observation of sacrificialbonding behavior in the inorganic phase of composite systems. Either continuous unraveling or discrete splaying of the coiled graphene sheets were found to dissipate energy by overcoming the relatively weak pi-pi interactions between stacked layers, yielding significant toughening at low nanofiber contents. Incorporation of these nanofibers into carbon-fiber-reinforced composites yielded mechanical enhancements in matrix-dominated properties while improving transverse electrical conductivity. Finally, the formation mechanism of freestanding graphene oxide films (or papers) fabricated by vacuum-assisted filtration of aqueous colloidal suspensions was examined as a function of both film

  6. Measurements of charmless b-hadron decays at CDF; first evidence for the annihilation $B^0_s \\to \\pi^+ \\pi^-$ decay mode.

    SciTech Connect

    Ruffini, Fabrizio

    2013-01-01

    This work of thesis will investigate the heavy flavor sector, involving decays of particles containing the most massive quarks. In particular, we will study the bhadrons, that means particles containing b-quarks. The topic of this work is the measurements of B and CP asymmetries of two-body charmless decays of neutral b-hadrons, (B0 (s) → h+h' - and Λ0 b →and ph -, where the h can be a pion or a kaon) collectively called B → h+h' -. Next sections describe the theoretical framework in which the b-hadrons are included. Firstly, it is necessary to introduce the CKM matrix describing the electroweak interactions between quarks and how the phenomenon of the CP violation manifests itself.

  7. Stacked and H-Bonded Cytosine Dimers. Analysis of the Intermolecular Interaction Energies by Parallel Quantum Chemistry and Polarizable Molecular Mechanics.

    PubMed

    Gresh, Nohad; Sponer, Judit E; Devereux, Mike; Gkionis, Konstantinos; de Courcy, Benoit; Piquemal, Jean-Philip; Sponer, Jiri

    2015-07-30

    Until now, atomistic simulations of DNA and RNA and their complexes have been executed using well calibrated but conceptually simple pair-additive empirical potentials (force fields). Although such simulations provided many valuable results, it is well established that simple force fields also introduce errors into the description, underlying the need for development of alternative anisotropic, polarizable molecular mechanics (APMM) potentials. One of the most abundant forces in all kinds of nucleic acids topologies is base stacking. Intra- and interstrand stacking is assumed to be the most essential factor affecting local conformational variations of B-DNA. However, stacking also contributes to formation of all kinds of noncanonical nucleic acids structures, such as quadruplexes or folded RNAs. The present study focuses on 14 stacked cytosine (Cyt) dimers and the doubly H-bonded dimer. We evaluate the extent to which an APMM procedure, SIBFA, could account quantitatively for the results of high-level quantum chemistry (QC) on the total interaction energies, and the individual energy contributions and their nonisotropic behaviors. Good agreements are found at both uncorrelated HF and correlated DFT and CCSD(T) levels. Resorting in SIBFA to distributed QC multipoles and to an explicit representation of the lone pairs is essential to respectively account for the anisotropies of the Coulomb and of the exchange-repulsion QC contributions. PMID:26119247

  8. Cross Sections for the Reactions e+e to K+ K- pi+pi-, K+ K- pi0pi0, and K+ K- K+ K- Measured Using Initial-State Radiation

    SciTech Connect

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

    2011-08-19

    We study the processes e{sup +}e{sup -} {yields} K{sup +}K{sup -}{pi}{sup +}{pi}-{gamma}, K{sup +}K{sup -}{pi}{sup 0}{pi}{sup 0}{gamma}, and K{sup +}K{sup -}K{sup +}K{sup -}{gamma}, where the photon is radiated from the initial state. About 84000, 8000, and 4200 fully reconstructed events, respectively, are selected from 454 fb{sup -1} of BABAR data. The invariant mass of the hadronic final state defines the e{sup +}e{sup -} center-of-mass energy, so that the K{sup +}K{sup -}{pi}{sup +}{pi}{sup -}{gamma} data can be compared with direct measurements of the e{sup +}e{sup -} {yields} K{sup +}K{sup -}{pi}{sup +}{pi}{sup -} reaction. No direct measurements exist for the e{sup +}e{sup -} {yields} K{sup +}K{sup -}{pi}{sup 0}{pi}{sup 0} or e{sup +}e{sup -} {yields} K{sup +}K{sup -}K{sup +}K{sup -} reactions, and we present an update of our previous result with doubled statistics. Studying the structure of these events, we find contributions from a number of intermediate states, and extract their cross sections. In particular, we perform a more detailed study of the e{sup +}e{sup -} {yields} {phi}(1020){pi}{pi}{gamma} reaction, and confirm the presence of the Y (2175) resonance in the {phi}(1020)f{sub 0}(980) and K{sup +}K{sup -} f{sub 0}(980) modes. In the charmonium region, we observe the J/{psi} in all three final states and in several intermediate states, as well as the {phi}(2S) in some modes, and measure the corresponding branching fractions.

  9. Stacking Up

    ERIC Educational Resources Information Center

    Naylor, Jim

    2005-01-01

    Chimneys and stacks appear to be strong and indestructible, but chimneys begin to deteriorate from the moment they are built. Early on, no signs are apparent; but deterioration accelerates in subsequent years, and major repairs are soon needed instead of minor maintenance. With proper attention, most structures can be repaired and continue to…

  10. Manifestation of π-π stacking interactions in luminescence properties and energy transfer in aromatically-derived Tb, Eu and Gd tris(pyrazolyl)borate complexes.

    PubMed

    Mikhalyova, Elena A; Yakovenko, Anastasiya V; Zeller, Matthias; Kiskin, Mikhail A; Kolomzarov, Yuriy V; Eremenko, Igor L; Addison, Anthony W; Pavlishchuk, Vitaly V

    2015-04-01

    The three new complexes Tp(Py)Ln(CH3CO2)2(H2O) (Ln = Eu (1), Gd(2), or Tb (3)) were prepared and characterized crystallographically. In the crystal lattices of these complexes, separate molecules are connected in infinite chains by π-stacking interactions. Complexes 1 and 3 display intense photoluminescence and triboluminescence (red and green respectively), while compound 3 exhibits electroluminescence commencing at 9 V in an ITO/PVK/3/Al device (ITO = indium-tin oxide, PVK = poly(N-vinylcarbazole)). A series of Eu/Tb-doped Gd compounds was prepared by cocrystallization from mixtures of 1 and 2 or 2 and 3, respectively. It was shown that π-stacking interactions are involved in increasing the efficiency of energy transfer from the gadolinium complex to emitting [Tp(Py)Eu](2+) or [Tp(Py)Tb](2+) centers, and this energy transfer occurs through hundreds of molecules, resembling the process of energy harvesting in chloroplast stacks. PMID:25797500

  11. Stacking with No Planarity?

    PubMed

    Gunaydin, Hakan; Bartberger, Michael D

    2016-04-14

    This viewpoint describes the results obtained from matched molecular pair analyses and quantum mechanics calculations that show unsaturated rings found in drug-like molecules may be replaced with their saturated counterparts without losing potency even if they are engaged in stacking interactions with the side chains of aromatic residues. PMID:27096037

  12. Quantum-mechanical computations on the electronic structure of trans-resveratrol and trans-piceatannol: a theoretical study of the stacking interactions in trans-resveratrol dimers.

    PubMed

    Mikulski, Damian; Molski, Marcin

    2012-07-01

    Accurate quantum-chemical calculations based on the second-order Møller-Plesset perturbation method (MP2) and density functional theory (DFT) were performed for the first time to investigate the electronic structures of trans-resveratrol and trans-piceatannol, as well as to study the stacking interaction between trans-resveratrol molecules. Ab initio MP2 calculations performed with using standard split-valence Pople basis sets led us to conclude that these compounds have structures that deviate strongly from planarity, whereas the DFT computations for the same basis sets revealed that the equilibrium geometries of these bioactive polyphenols are planar. Furthermore, the results obtained at the MP2(full)/aug-cc-pVTZ and B3LYP/aug-cc-pVTZ levels indicated that the geometries of trans-resveratrol and trans-piceatannol are practically planar at their absolute energy minima. The relative energies of the equilibrium geometries of trans-resveratrol on its potential energy surface were computed at the MP2(full)/aug-cc-pVTZ level. According to the results obtained, a T-shaped (edge-to-phase) conformer of trans-resveratrol dimer is the most stable in vacuum. This T-shaped conformer is mainly stabilized by strong hydrogen bonding and weak C-H...π interactions. Stacked structures with parallel-displaced trans-stilbene skeletons were also found to be energetically stable. The vertical separation and twist angle dependencies of the stacking energy were investigated at the MP2(full)/aug-cc-pVTZ, B3LYP/aug-cc-pVTZ, and HF/aug-cc-pVTZ levels. The standard B3LYP functional and the Hartree-Fock method neglect long-range attractive dispersion interactions. The MP2 computations revealed that the London dispersion energy cannot be neglected at long or short distances. The stacked model considered here may be useful for predicting the quantum nature of the interactions in π-stacked systems of other naturally occurring stilbenoids, and can help to enhance our understanding of the

  13. Pressure-Induced Phase Transitions in Ammonium Squarate: A Supramolecular Structure Based on Hydrogen-Bonding and [pi]-Stacking Interactions

    SciTech Connect

    Li, Shourui; Wang, Kai; Zhou, Mi; Li, Qian; Liu, Bingbing; Zou, Guangtian; Zou, Bo

    2012-02-06

    We report the results of high-pressure Raman and X-ray diffraction measurements performed on ammonium squarate ((NH{sub 4}){sub 2}C{sub 4}O{sub 4}, AS), a representative supramolecular architecture based on hydrogen bonding and {pi}-stacking interactions, at various pressures up to 19 GPa. Two phase transitions at 2.7 GPa and in the pressure range of 11.1-13.6 GPa were observed. Both Raman and XRD results provide convincing evidence for these two phase transitions. The first phase transition is attributed to the rearrangements of hydrogen-bonding networks, resulting in the symmetry transformation from P2{sub 1}/c to P1. The second one, which is identified as an order-disorder phase transition, arises from significant modifications of squarate rings and random orientations of NH{sub 4}{sup +} cations. The cooperative effects between hydrogen-bonding and {pi}-stacking interactions, as well as mechanisms for the phase transitions, are discussed by virtue of the local structure of AS.

  14. Glucose-β-CD interaction assisted ACN field-amplified sample stacking in CZE for determination of trace amlodipine in beagle dog plasma.

    PubMed

    Li, Ji; Li, You; Zhang, Wenting; Chen, Zhao; Fan, Guorong

    2013-06-01

    A simple, sensitive and low-cost method using CE coupled with glucose-β-CD interaction assisted ACN stacking technique has been developed for quantification of trace amlodipine in dog plasma. The plasma samples were extracted with methyl tert-butyl ether. The separation was performed at 25°C in a 31.2 cm × 75 μm fused-silica capillary with an applied voltage of 15 kV. The BGE was composed of 6.25 mM borate/25 mM phosphate (pH 2.5) and 5 mg/mL glucose-β-CD. The detection wavelength was 200 nm. Because CD could diminish the interaction between drugs and matrix, and derivation groups of CD play an important role in separation performance, the effects of β-CD, and its derivatives on the separation were studied at several concentrations (0, 2.5, 5.0, 10.0 mg/mL). In this study, organic solvent field-amplified sample stacking technique in combination with glucose-β-CD enhanced the sensitivity about 60-70 folds and glucose-β-CD could effectively improve the peak shape. All the validation data, such as accuracy, precision extraction recovery, and stability, were within the required limits. The calibration curve was linear for amlodipine from 1 to 200 ng/mL. The method developed was successfully applied to the pharmacokinetic studies of amlodipine besylate in beagle dogs. PMID:23495256

  15. Evolution and interaction of twins, dislocations and stacking faults in rolled α-brass during nanostructuring at sub-zero temperature

    NASA Astrophysics Data System (ADS)

    Roy, Barna; Kumar, Nand Kishor; Nambissan, Padinharu Madathil Gopalakrishnan; Das, Jayanta

    2014-06-01

    The effect of cryorolling (CR) strain at 153 K on the evolution of structural defects and their interaction in α-brass (Cu-30 wt.% Zn) during nanostructuring has been evaluated. Even though the lattice strain increases up to 2.1 × 10-3 at CR strain of 0.6 initially, but it remains constant upon further rolling. Whereas, the twin density (β) increases to a maximum value of 5.9 × 10-3 at a CR strain of 0.7 and reduces to 1.1 × 10-5 at 0.95. Accumulation of stacking faults (SFs) and lattice disorder at the twin boundaries causes dynamic recrystallization, promotes grain refinement and decreases the twin density by forming subgrains. Detailed investigations on the formation and interaction of defects have been done through resistivity, positron lifetime and Doppler broadening measurements in order to understand the micro-mechanism of nanostructuring at sub-zero temperatures.

  16. A Survey of Aspartate-Phenylalanine and Glutamate-Phenylalanine Interactions in the Protein Data Bank: Searching for Anion-pi Pairs

    SciTech Connect

    Philip, Vivek M; Harris, Jason B; Adams, Rachel M; Nguyen, Don; Spiers, Jeremy D; Baudry, Jerome Y; Howell, Elizabeth E; Hinde, Robert J

    2011-01-01

    Protein structures are stabilized using noncovalent interactions. In addition to the traditional noncovalent interactions, newer types of interactions are thought to be present in proteins. One such interaction, an anion-{pi} pair, in which the positively charged edge of an aromatic ring interacts with an anion, forming a favorable anion-quadrupole interaction, has been previously proposed [Jackson, M. R., et al. (2007) J. Phys. Chem. B111, 8242-8249]. To study the role of anion-{pi} interactions in stabilizing protein structure, we analyzed pairwise interactions between phenylalanine (Phe) and the anionic amino acids, aspartate (Asp) and glutamate (Glu). Particular emphasis was focused on identification of Phe-Asp or -Glu pairs separated by less than 7 {angstrom} in the high-resolution, nonredundant Protein Data Bank. Simplifying Phe to benzene and Asp or Glu to formate molecules facilitated in silico analysis of the pairs. Kitaura-Morokuma energy calculations were performed on roughly 19000 benzene-formate pairs and the resulting energies analyzed as a function of distance and angle. Edgewise interactions typically produced strongly stabilizing interaction energies (-2 to -7.3 kcal/mol), while interactions involving the ring face resulted in weakly stabilizing to repulsive interaction energies. The strongest, most stabilizing interactions were identified as preferentially occurring in buried residues. Anion-{pi} pairs are found throughout protein structures, in helices as well as {beta} strands. Numerous pairs also had nearby cation-{pi} interactions as well as potential {pi}-{pi} stacking. While more than 1000 structures did not contain an anion-{pi} pair, the 3134 remaining structures contained approximately 2.6 anion-{pi} pairs per protein, suggesting it is a reasonably common motif that could contribute to the overall structural stability of a protein.

  17. Resonant interaction of light with a stack of alternating layers of a cholesteric liquid crystal and an isotropic medium

    NASA Astrophysics Data System (ADS)

    Gevorgyan, A. H.

    2015-12-01

    Resonance properties of a stack consisting of a cholesteric liquid crystal and isotropic medium layers are investigated. Bragg's conditions for photonic band gaps are presented for the considered system. It is shown that a significant control of the system zone structure is possible in the case of a proper selection of the sublayer parameters. It is also shown that an effect of complete suppression of absorption is not usually observed in the case of anisotropic absorption in cholesteric liquid crystal sublayers. The possibility to achieve this effect in the considered system, imposing certain conditions on the thickness and the refraction index of the isotropic medium sublayers, is shown. Also, it is shown that in such conditions a large increase of the maximum of photonic density of states happens at the appropriate zone borders.

  18. Supramolecular self-assembly of a coumarine-based acylthiourea synthon directed by π-stacking interactions: Crystal structure and Hirshfeld surface analysis

    NASA Astrophysics Data System (ADS)

    Saeed, Aamer; Ashraf, Saba; Flörke, Ulrich; Delgado Espinoza, Zuly Yuliana; Erben, Mauricio F.; Pérez, Hiram

    2016-05-01

    The structure of 1-(2-oxo-2H-chromene-3-carbonyl)-3-(2-methoxy-phenyl)thiourea (1) has been determined by single-crystal X-ray crystallography. This compound crystallizes in the monoclinic space group P21/c with a = 7.455 (2) Å, b = 12.744 (3) Å, c = 16.892 (4) Å, β = 90.203 (6)° and Z = 4. Both, the coumarin and the phenyl rings are nearly coplanar with the central 1-acylthiourea group, with the Cdbnd O and Cdbnd S bonds adopting an opposite orientation. Intramolecular N-H···O, C-H···O, and C-H···S hydrogen bonds are favored by the planar conformation. The molecules are packed through C-H···O, C-H···S and C-H···C hydrogen bonds, and two π···π interactions with offset arrangement. Inter-centroid distance of 3.490 (2) Å, slip angles of 18.5 and 20.9°, and vertical displacements of 1.10 and 1.24 Å are the stacking parameters corresponding to the stronger π···π interaction. Hirshfeld surface analysis was performed for visualizing, exploring and quantifying intermolecular interactions in the crystal lattice of compound 1, and compared with two closely related species. Shape index and Curvedness surfaces indicated π-stacking with different features in opposed sides of the molecule. Fingerprint plot showed C···C contacts with similar contributions to the crystal packing in comparison with those associated to hydrogen bonds. Enrichment ratios for H···H, O···H, S···H and C···C contacts revealed a high propensity to form in the crystal.

  19. π-Stacking attraction vs. electrostatic repulsion: competing supramolecular interactions in a tpphz-bridged Ru(ii)/Au(iii) complex.

    PubMed

    Sorsche, Dieter; Schaub, Markus; Heinemann, Frank W; Habermehl, Johannes; Kuhri, Susanne; Guldi, Dirk; Guthmuller, Julien; Rau, Sven

    2016-08-01

    The synthesis and characterization of a mixed metal ruthenium(ii)/gold(iii) complex bridged by tetrapyridophenazine (tpphz) are described. It is isostructural and isoelectronic to the well-known photocatalysts with palladium(ii) or platinum(ii). Concentration dependent (1)H-NMR spectroscopy and XRD studies show that the electrostatic repulsion between the gold(iii) moieties exceeds the attractive π-stacking interaction. Theoretical calculations based on the new structural data confirm an increased positive charge on the bridging ligand as well as significantly altered orbital symmetry as compared to the previously investigated palladium(ii) complex. This is the first example of a tpphz ruthenium(ii) complex where π-stacking is completely inhibited. The detailed investigation of the solid-state structure showed for the first time in bimetallic tpphz bridged complexes no significant torsion within the bridging ligand itself. Although catalytic performance for proton reduction by gold(iii) is naturally not observed, its photochemical decomposition in colloidal gold particles could be shown by TEM and DLS. PMID:27472004

  20. A bundled-stack discotic columnar liquid crystalline phase with inter-stack electronic coupling

    DOE PAGESBeta

    Wang, Bin; Sun, Runkun; Günbaş, Duygu D.; Zhang, Hao; Grozema, Ferdinand C.; Xiao, Kai; Jin, Shi

    2015-06-15

    The first compound proving to be capable of forming a bundled-stack discotic columnar liquid crystalline (BSDCLC) phase was designed and synthesized. Finally, the unique perylene anhydride inter-stack interaction was found to be the key to the formation of the BSDCLC structure and inter-stack electronic coupling (ISEC).

  1. Bundled Stack Discotic Columnar Liquid Crystalline Phase with Inter Stack Electronic Coupling

    SciTech Connect

    Wang, Bin; Sun, Runkun; Gunbas, Duygu; Zhang, Hao; Grozema, Ferdinand; Xiao, Kai; Jin, Shi

    2015-01-01

    The first compound capable of forming a bundled stack discotic columnar liquid crystalline (BSDCLC) phase was designed and synthesized. The unique perylene anhydride inter stack interaction was found to be the key to the formation of the BSDCLC structure and inter stack electronic coupling (ISEC).

  2. Study of the Tau- to Pi- Pi+ Pi- Pi0 Nu/Tau And Tau- to Pi- Pi- Pi+ Eta Nu/Tau Decays Using the BaBar Detector

    SciTech Connect

    Sobie, Randall; /Victoria U.

    2007-11-14

    The {tau}{sup -} {yields} {pi}{sup -}{pi}{sup +}{pi}{sup -}{nu}{sub {tau}} and {tau}{sup -} {yields} {pi}{sup -}{pi}{sup -}{pi}{sup +}{eta}{nu}{sub {tau}} decays have been studied with the BABAR detector. Preliminary branching fractions on the two modes are presented. The {tau}{sup -} {yields} {pi}{sup -}{pi}{sup -}{pi}{sup +}{eta}{nu}{sub {tau}} mode is found to have a large contribution from the {tau}{sup -} {yields} {omega}{pi}{sup -}{nu}{sub {tau}} decay. The {tau}{sup -} {yields} {pi}{sup -}{pi}{sup -}{pi}{sup +}{eta}{nu}{sub {tau}} decay is studied using the {eta} {yields} {gamma}{gamma} mode and the {tau}{sup -} f{sub 1}(1285){pi}{sup -}{nu}{sub {tau}} decay is seen to be the primary source of these decays. A 90% confidence level upper limit is placed on the {tau}{sup -} {yields} {eta}{prime}(958){pi}{sup -}{nu}{sub {tau}} decay which proceeds through a second-class current and is expected to be forbidden in the limit of perfect isospin symmetry.

  3. Electrochemical cell stack assembly

    DOEpatents

    Jacobson, Craig P.; Visco, Steven J.; De Jonghe, Lutgard C.

    2010-06-22

    Multiple stacks of tubular electrochemical cells having a dense electrolyte disposed between an anode and a cathode preferably deposited as thin films arranged in parallel on stamped conductive interconnect sheets or ferrules. The stack allows one or more electrochemical cell to malfunction without disabling the entire stack. Stack efficiency is enhanced through simplified gas manifolding, gas recycling, reduced operating temperature and improved heat distribution.

  4. Structural Studies on Porphyrin-PNA Conjugates in Parallel PNA:PNA Duplexes: Effect of Stacking Interactions on Helicity.

    PubMed

    Accetta, Alessandro; Petrovic, Ana G; Marchelli, Rosangela; Berova, Nina; Corradini, Roberto

    2015-12-01

    Parallel PNA:PNA duplexes were synthesized and conjugated with meso-tris(pyridyl)phenylporphyrin carboxylic acid at the N-terminus. The introduction of one porphyrin unit was shown to affect slightly the stability of the PNA:PNA parallel duplex, whereas the presence of two porphyrin units at the same end resulted in a dramatic increase of the melting temperature, accompanied by hysteresis between melting and cooling curves. The circular dichroism (CD) profile of the Soret band and fluorescence quenching strongly support the occurrence of a face-to-face interaction between the two porphyrin units. Introduction of a L-lysine residue at the C-terminal of one strand of the parallel duplex induced a left-handed helical structure in the PNA:PNA duplex if the latter contains only one or no porphyrin moiety. The left-handed helicity was revealed by nucleobase CD profile at 240-280 nm and by the induced-CD observed in the presence of the DiSC2 (5) cyanine dye at ~500-550 nm. Surprisingly, the presence of two porphyrin units led to the disappearance of the nucleobase CD signal and the absence of CD exciton coupling within the Soret band region. In addition, a dramatic decrease of induced CD of DiSC2 (5) was observed. These results are in agreement with a model where the porphyrin-porphyrin interactions cause partial loss of chirality of the PNA:PNA parallel duplex, forcing it to adopt a ladder-like conformation. PMID:26412743

  5. Multiplet earthquake relocations and stacked waveform inversions in the Yellowstone volcanic field and implications for volcanic-tectonic interactions

    NASA Astrophysics Data System (ADS)

    Massin, F.; Farrell, J.; Smith, R. B.; Shelly, D. R.

    2012-12-01

    Abnormally high earthquake rates and episodic crustal deformation suggest that the Yellowstone hotspot affects the tectonics of the western United States. However the relationship between the Yellowstone volcanic system and the surrounding tectonic regime remains poorly known. We study the structure and stress field for quantitative modeling of volcano-tectonic interactions using multiplet analysis. Our analysis shows that earthquake rates of Yellowstone are coincident with the uplift and subsidence episodes of the 0.64 Ma Yellowstone caldera: a relative decrease of multiplet activity accompanies each subsidence episode between 1997 and 2010. Our research focuses on the determination of crustal seismogenic structures and related stress perturbations that are responsible for the abnormally intense and cyclic earthquake activity. We consider each multiplet as a homogenous set of earthquakes produced by the same seismic source or fault. We integrate results from double-difference hypocenter relocations and source mechanism determinations to evaluate active fault properties. Hypocenters are constrained by a median of 50 P-wave and 12 S-wave differential arrival times (up to 4062 P-waves and 1187 S-waves). Composite focal mechanism solutions are determined for multiplets with 64 P-wave polarity observations or more. We compare multilinear regression planes of hypocenters of large multiplets and their composite focal mechanisms to choose fault planes and slip directions. We then develop detailed analysis of the largest earthquake swarms in Yellowstone, e.g. the Autumn 1985, the 2008 Yellowstone Lake and the 2010 Madison Plateau earthquake swarms to examine if swarm earthquakes occur on one continuous fault plane or on a network of independent segments with variable orientations. To independently confirm the interpreted fault plane we also invert for the moment tensors of the largest multiplets with a cumulative seismic moment over Mw3. The moment tensors are decomposed

  6. Three-body Final State Interaction in η→3π

    SciTech Connect

    Guo, Peng; Danilkin, Igor V.; Schott, Diane; Fernández-Ramírez, C.; Mathieu, V.; Szczepaniak, Adam P.

    2015-09-11

    We present an unitary dispersive model for the $\\eta \\to 3 \\pi$ decay process based upon the Khuri-Treiman equations which are solved by means of the Pasquier inversion method. The description of the hadronic final-state interactions for the $\\eta \\to 3\\pi$ decay is essential to reproduce the available data and to understand the existing discrepancies between Dalitz plot parameters from experiment and chiral perturbation theory. Our approach incorporates substraction constants that are fixed by fitting the recent high-statistics WASA-at-COSY data for $\\eta \\to \\pi^+ \\pi^- \\pi^0$. Based on the parameters obtained we predict the slope parameter for the neutral channel to be $\\alpha=-0.022\\pm 0.004$. Through matching to next-to-leading order chiral perturbation theory we estimate the quark mass double ratio to be $Q=21.4 \\pm 0.4$.

  7. Three-body Final State Interaction in η→3π

    DOE PAGESBeta

    Guo, Peng; Danilkin, Igor V.; Schott, Diane; Fernández-Ramírez, C.; Mathieu, V.; Szczepaniak, Adam P.

    2015-09-11

    We present an unitary dispersive model for themore » $$\\eta \\to 3 \\pi$$ decay process based upon the Khuri-Treiman equations which are solved by means of the Pasquier inversion method. The description of the hadronic final-state interactions for the $$\\eta \\to 3\\pi$$ decay is essential to reproduce the available data and to understand the existing discrepancies between Dalitz plot parameters from experiment and chiral perturbation theory. Our approach incorporates substraction constants that are fixed by fitting the recent high-statistics WASA-at-COSY data for $$\\eta \\to \\pi^+ \\pi^- \\pi^0$$. Based on the parameters obtained we predict the slope parameter for the neutral channel to be $$\\alpha=-0.022\\pm 0.004$$. Through matching to next-to-leading order chiral perturbation theory we estimate the quark mass double ratio to be $$Q=21.4 \\pm 0.4$$.« less

  8. The polar 2e/12c bond in phenalenyl-azaphenalenyl hetero-dimers: Stronger stacking interaction and fascinating interlayer charge transfer

    NASA Astrophysics Data System (ADS)

    Zhong, Rong-Lin; Xu, Hong-Liang; Li, Zhi-Ru

    2016-08-01

    An increasing number of chemists have focused on the two-electron/multicenter bond (2e/mc) that was first introduced to interpret the bonding mechanism of radical dimers. Herein, we report the polar two-electron/twelve center (2e/12c) bonding character in a series of phenalenyl-azaphenalenyl radical hetero-dimers. Interestingly, the bonding energy of weaker polar hetero-dimer (P-TAP) is dominated by the overlap of the two different singly occupied molecular orbital of radicals, while that of stronger polar hetero-dimer (P-HAP) is dominated by the electrostatic attraction. Results show that the difference between the electronegativity of the monomers plays a prominent role in the essential attribution of the polar 2e/12c bond. Correspondingly, a stronger stacking interaction in the hetero-dimer could be effectively achieved by increasing the difference of nitrogen atoms number between the monomers. It is worthy of note that an interesting interlayer charge transfer character is induced in the polar hetero-dimers, which is dependent on the difference between the electronegativity of the monomers. It is our expectation that the new knowledge about the bonding nature of radical hetero-dimers might provide important information for designing radical based functional materials with various applications.

  9. Unraveling Base Stacking Driving Forces in DNA.

    PubMed

    Mak, Chi H

    2016-07-01

    Base stacking is a key determinant of nucleic acid structures, but the precise origin of the thermodynamic driving force behind the stacking of nucleobases remains open. The rather mild stacking free energy measured experimentally, roughly a kcal/mol depending on the identity of the bases, is physiologically significant because while base stacking confers stability to the genome in its double helix form, the duplex also has to be unwound in order to be replicated or transcribed. A stacking free energy that is either too high or too low will over- or understabilize the genome, impacting the storage of genetic information and also its retrieval. While the molecular origin of stacking driving force has been attributed to many different sources including dispersion, electrostatics, and solvent hydrogen bonding, here we show via a systematic decomposition of the stacking free energy using large-scale computer simulations that the dominant driving force stabilizing base stacking is nonhydrophobic solvent entropy. Counteracting this is the conformational entropic penalty on the sugar-phosphate backbone against stacking, while solvent hydrogen-bonding, charge-charge interactions, and dispersive forces produce only secondary perturbations. Solvent entropic forces and DNA backbone conformational strains therefore work against each other, leading to a very mild composite stacking free energy in agreement with experiments. PMID:27045853

  10. Fifty years of stacking

    NASA Astrophysics Data System (ADS)

    Rashed, Mohamed

    2014-06-01

    Common-Mid-Point (CMP) stacking is a major process to enhance signal-to-noise ratio in seismic data. Since its appearance fifty years ago, CMP stacking has gone through different phases of prosperity and negligence within the geophysical community. During those times, CMP stacking developed from a simple process of averaging into a sophisticated process that involves complicated mathematics and state-of-the-art computation. This article summarizes the basic principles, assumptions, and violations related to the CMP stacking technique, presents a historical overview on the development stages of CMP stacking, and discusses its future potentiality.

  11. A series of Cd(II) complexes with π-π stacking and hydrogen bonding interactions: Structural diversities by varying the ligands

    NASA Astrophysics Data System (ADS)

    Wang, Xiuli; Zhang, Jinxia; Liu, Guocheng; Lin, Hongyan

    2011-02-01

    Seven new Cd(II) complexes consisting of different phenanthroline derivatives and organic acid ligands, formulated as [Cd(PIP) 2(dnba) 2] ( 1), [Cd(PIP)(ox)]·H 2O ( 2), [Cd(PIP)(1,4-bdc)(H 2O)]·4H 2O ( 3), [Cd(3-PIP) 2(H 2O) 2]·4H 2O ( 4), [Cd 2(3-PIP) 4(4,4'-bpdc)(H 2O) 2]·5H 2O ( 5), [Cd(3-PIP)(nip)(H 2O)]·H 2O ( 6), [Cd 2(TIP) 4(4,4'-bpdc)(H 2O) 2]·3H 2O ( 7) (PIP=2-phenylimidazo[4,5- f]1,10-phenanthroline, 3-PIP=2-(3-pyridyl)imidazo[4,5- f]1,10-phenanthroline, TIP=2-(2-thienyl)imidazo[4,5- f]1,10-phenanthroline, Hdnba=3,5-dinitrobenzoic acid, H 2ox=oxalic acid, 1,4-H 2bdc=benzene-1,4-dicarboxylic acid, 4,4'-H 2bpdc=biphenyl-4,4'-dicarboxylic acid, H 2nip=5-nitroisophthalic acid) have been synthesized under hydrothermal conditions. Complexes 1 and 4 possess mononuclear structures; complexes 5 and 7 are isostructural and have dinuclear structures; complexes 2 and 3 feature 1D chain structures; complex 6 contains 1D double chain, which are further extended to a 3D supramolecular structure by π- π stacking and hydrogen bonding interactions. The N-donor ligands with extended π-system and organic acid ligands play a crucial role in the formation of the final supramolecular frameworks. Moreover, thermal properties and fluorescence of 1- 7 are also investigated.

  12. Stacking with stochastic cooling

    NASA Astrophysics Data System (ADS)

    Caspers, Fritz; Möhl, Dieter

    2004-10-01

    Accumulation of large stacks of antiprotons or ions with the aid of stochastic cooling is more delicate than cooling a constant intensity beam. Basically the difficulty stems from the fact that the optimized gain and the cooling rate are inversely proportional to the number of particles 'seen' by the cooling system. Therefore, to maintain fast stacking, the newly injected batch has to be strongly 'protected' from the Schottky noise of the stack. Vice versa the stack has to be efficiently 'shielded' against the high gain cooling system for the injected beam. In the antiproton accumulators with stacking ratios up to 105 the problem is solved by radial separation of the injection and the stack orbits in a region of large dispersion. An array of several tapered cooling systems with a matched gain profile provides a continuous particle flux towards the high-density stack core. Shielding of the different systems from each other is obtained both through the spatial separation and via the revolution frequencies (filters). In the 'old AA', where the antiproton collection and stacking was done in one single ring, the injected beam was further shielded during cooling by means of a movable shutter. The complexity of these systems is very high. For more modest stacking ratios, one might use azimuthal rather than radial separation of stack and injected beam. Schematically half of the circumference would be used to accept and cool new beam and the remainder to house the stack. Fast gating is then required between the high gain cooling of the injected beam and the low gain stack cooling. RF-gymnastics are used to merge the pre-cooled batch with the stack, to re-create free space for the next injection, and to capture the new batch. This scheme is less demanding for the storage ring lattice, but at the expense of some reduction in stacking rate. The talk reviews the 'radial' separation schemes and also gives some considerations to the 'azimuthal' schemes.

  13. Transformation from a 2D stacked layer to 3D interpenetrated framework by changing the spacer functionality: synthesis, structure, adsorption, and magnetic properties.

    PubMed

    Maji, Tapas Kumar; Ohba, Masaaki; Kitagawa, Susumu

    2005-12-12

    Two novel coordination polymers of Cu(II), viz. [Cu(bipy)(1,4-napdc)(H2O)2]n and {[Cu(bpe)1.5(1,4-napdc)](H2O)}n (bipy=4,4'-bipyridine; bpe=1,2-bis(4-pyridyl)ethane; 1,4-napdc2-=1,4-naphthalenedicarboxylate), have been synthesized and structurally characterized by changing only the pillar motifs. Both the compounds crystallize by slow evaporation from the ammoniacal solution of the as-synthesized solid. Framework 1 crystallizes in monoclinic crystal system, space group P2/n (No. 13), with a=11.028(19) A, b=11.16(3) A, c=7.678(13) A, beta=103.30(5) degrees, and Z=2. Framework 2 crystallizes in triclinic system, space group, P (No. 2), a=10.613(4) A, b=10.828(10) A, c=13.333(9) A, alpha=85.25(9) degrees, beta=82.59(6) degrees, gamma=60.37(5) degrees, and Z=2. The structure determination reveals that has a 2D network based on rectangular grids, where each Cu(II) is in 4+2 coordination mode. The 2D networks stacked in a staggered manner through the pi-pi interaction to form a 3D supramolecular network. In the case of, a {Cu(bpe)1.5}n ladder connected by 1,4-napdc2- results a 2D cuboidal bilayer network and each bilayer network is interlocked by two adjacent identical network (upper and lower) forming 3-fold interpenetrated 3D framework with small channel along the c-axis, which accommodates two water molecules. The TGA and XRPD measurements reveal that both the frameworks are stable after dehydration. Adsorption measurements (N2, CO2, and different solvents, like H2O, MeOH, etc.) were carried out for both frameworks. Framework shows type-II sorption profile with N2 in contrast to H2O and MeOH, which are chemisorbed in the framework. In case of, only H2O molecules can diffuse into the micropore, whereas N2, CO2, and MeOH cannot be adsorbed, as corroborated by the smaller channel aperture. The low-temperature (300-2 K) magnetic measurement of and reveals that both are weakly antiferromagnetically coupled (J=-1.85 cm-1, g=2.02; J=-0.153 cm-1, g=2.07), which is correlated

  14. Stacking Global Seismograms Revisited

    NASA Astrophysics Data System (ADS)

    Shearer, P. M.; Buehler, J. S.; Denolle, M.; Fan, W.; Ma, Z.; Mancinelli, N. J.; Matoza, R. S.; Wang, W.; Wang, Y.; Zhan, Z.

    2014-12-01

    Over 20 years ago, stacks of global seismograms produced direct images of the global seismic wavefield highlighting the visibility, frequency content, and polarity of known seismic phases, and also identified a host of new phases associated with reflections and phase conversions from upper-mantle discontinuities. Two different stacking methods proved particularly useful: (1) STA/LTA-filtered stacks that describe the local signal-to-noise characteristics of the major seismic phases. These serve to image the entire wavefield in a uniform way for educational purposes and to show which phases are observed most clearly as a guide to future research. These stacks also resolve SH versus SV timing differences consistent with radial anisotropy. (2) Reference-phase stacks that preserve the polarity, amplitude, and timing of traces with respect to a specified target phase. These show a large number of top-side and bottom-side reflections and phase conversions from the 410- and 660-km discontinuities that create weak phases with a characteristic "railroad track" appearance both preceding and following many of the main seismic phases. Reference-phase stacking can also be used to produce coherent surface-wave stacks at very long periods, which directly show the dispersive character of the surface waves. Here we revisit and update these stacks by exploiting the vastly increased data now available from the IRIS DMC to produce greatly improved wavefield images. We present several examples of the different stacking approaches and point out their various features, including promising targets for future research.

  15. The effect of pi-stacking, h-bonding, and electrostatic interactions on the ionization energies of nucleic acid bases: adenine-adenine, thymine-thymine and adenine-thymine dimers

    SciTech Connect

    Bravaya, Ksenia B.; Kostko, Oleg; Ahmed, Musahid; Krylov, Anna I.

    2009-09-02

    A combined theoretical and experimental study of the ionized dimers of thymine and adenine, TT, AA, and AT, is presented. Adiabatic and vertical ionization energies(IEs) for monomers and dimers as well as thresholds for the appearance of the protonated species are reported and analyzed. Non-covalent interactions stronglyaffect the observed IEs. The magnitude and the nature of the effect is different for different isomers of the dimers. The computations reveal that for TT, the largestchanges in vertical IEs (0.4 eV) occur in asymmetric h-bonded and symmetric pi- stacked isomers, whereas in the lowest-energy symmetric h-bonded dimer the shiftin IEs is much smaller (0.1 eV). The origin of the shift and the character of the ionized states is different in asymmetric h-bonded and symmetric stacked isomers. Inthe former, the initial hole is localized on one of the fragments, and the shift is due to the electrostatic stabilization of the positive charge of the ionized fragment by thedipole moment of the neutral fragment. In the latter, the hole is delocalized, and the change in IE is proportional to the overlap of the fragments' MOs. The shifts in AAare much smaller due to a less effcient overlap and a smaller dipole moment. The ionization of the h-bonded dimers results in barrierless (or nearly barrierless) protontransfer, whereas the pi-stacked dimers relax to structures with the hole stabilized by the delocalization or electrostatic interactions.

  16. Observation of pi+ pi- pi+pi- photoproduction in ultraperipheral heavy-ion collisons at sqrt sNN = 200 GeV at the STAR Detector

    SciTech Connect

    Abelev, B.I.; Dunlop, J.; et al. STAR Collaboration

    2010-04-02

    We present a measurement of {pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} photonuclear production in ultraperipheral Au-Au collisions at {radical}s{sub NN} = 200 GeV from the STAR experiment. The {pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} final states are observed at low transverse momentum and are accompanied by mutual nuclear excitation of the beam particles. The strong enhancement of the production cross section at low transverse momentum is consistent with coherent photoproduction. The {pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} invariant mass spectrum of the coherent events exhibits a broad peak around 1540 {+-} 40 MeV/c{sup 2} with a width of 570 {+-} 60 MeV/c{sup 2}, in agreement with the photoproduction data for the {rho}{sup 0}(1700). We do not observe a corresponding peak in the {pi}{sup +}{pi}{sup -} final state and measure an upper limit for the ratio of the branching fractions of the {rho}{sup 0}(1700) to {pi}{sup +}{pi}{sup -} and {pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} of 2.5% at 90% confidence level. The ratio of {rho}{sup 0}(1700) and {rho}{sup 0}(770) coherent production cross sections is measured to be 13.4 {+-} 0.8{sub stat.}{+-}4.4{sub syst.}%.

  17. Observation of pi+pi-pi+pi- photoproduction in ultraperipheral heavy-ion collisions at sqrt sNN = 200 GeV at the STAR detector

    SciTech Connect

    STAR Collaboration; Abelev, Betty

    2010-07-05

    We present a measurement of {pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} photonuclear production in ultra-peripheral Au-Au collisions at {radical}s{sub NN} = 200 GeV from the STAR experiment. The {pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} final states are observed at low transverse momentum and are accompanied by mutual nuclear excitation of the beam particles. The strong enhancement of the production cross section at low transverse momentum is consistent with coherent photoproduction. The {pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} invariant mass spectrum of the coherent events exhibits a broad peak around 1540 {+-} 40 MeV/c{sup 2} with a width of 570 {+-} 60 MeV/c{sup 2}, in agreement with the photoproduction data for the {rho}{sup 0}(1700). We do not observe a corresponding peak in the {pi}{sup +}{pi}{sup -} final state and measure an upper limit for the ratio of the branching fractions of the {rho}{sup 0}(1700) to {pi}{sup +}{pi}{sup -} and {pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} of 2.5% at 90% confidence level. The ratio of {rho}{sup 0}(1700) and {rho}{sup 0}(770) coherent production cross sections is measured to be 13.4 {+-} 0.8{sub stat.} {+-} 4.4{sub syst.}%.

  18. Stack gas treatment

    DOEpatents

    Reeves, Adam A.

    1977-04-12

    Hot stack gases transfer contained heat to a gravity flow of pebbles treated with a catalyst, cooled stacked gases and a sulfuric acid mist is withdrawn from the unit, and heat picked up by the pebbles is transferred to air for combustion or other process. The sulfuric acid (or sulfur, depending on the catalyst) is withdrawn in a recovery unit.

  19. Design and synthesis of organic semiconductors with strong noncovalent interactions

    NASA Astrophysics Data System (ADS)

    Tucker, Neil Maxwell

    2008-10-01

    The development of organic molecules as active components of electronic and optoelectronic devices has seen unprecedented progress in the past decade. This attention is primarily due to the potential impact on large-area and low-cost fabrication of devices, integrated circuits, flexible displays, and in particular, organic field-effect transistors (OFETs). Organic semiconductors that pack face-to-face in the solid state are of particular interest since they are known to self-assemble into 1-D nanostructures due to strong pi-pi interactions. Engineering linear/planar molecules to pack face-to-face is challenging because the interacting forces between organic molecules are relatively weak. Three approaches were used to induce face-to-face packing in organic semiconductors: (1) several derivatives of hexaazatrinaphthylene, (HATNA), were designed which vary in their degree of hydrogen bonding, rigidity, and electron deficiency. Hydrogen bonded moieties induced strong interaction between cores that formed robust nanowires when subjected to nonpolar solvents. While no device data was measured for these materials, substituents location was found to have a profound effect on the electronic properties; (2) Inspired by S···S interactions found in tetrathiafulvalene (TTF) and electrostatic interactions found in 1,2,5-thiadiazole derivatives, a hybrid of these two molecules was developed (BT-TTF-1). Short intermolecular S···S, S···N, and S···C contacts define the solid state structure of BT-TTF-1 single crystals which pi-stack along the [100]. Theoretical insight into the nature of the interactions revealed that the close contacts are electrostatic in origin rather than the result of London dispersion forces. Thermal evaporation yields a network of poorly connected crystals which significantly limits the mobility. Solvent-cast single-crystal nanowire transistors showed mobilities as large as 0.36 cm2/Vs with excellent device characteristics underscoring the

  20. Rare Nonleptonic Decays of the Omega Hyperon: Measurements of the Branching Ratios for Omega-+ --> Xi*0(1530) (anti-Xi*0(1530)) pi-+ and Omega-+ --> Xi-+ pi+- pi-+

    SciTech Connect

    Kamaev, Oleg; /IIT, Chicago

    2007-12-01

    A clean signal of 78 (24) events has been observed in the rare nonleptonic particle (antiparticle) decay modes {Omega}{sup {-+}} {yields} {Xi}{sup {-+}}{pi}{sup {+-}}{pi}{sup {-+}} using data collected with the HyperCP spectrometer during Fermilab's 1999 fixed-target run. We obtain B({Omega}{sup -} {yields} {Xi}{sup -}{pi}{sup +}{pi}{sup -}) = [4.32 {+-} 0.56(stat) {+-} 0.28(syst)] x 10{sup -4} and B({Omega}{sup +} {yields} {Xi}{sup +}{pi}{sup -}{pi}{sup +}) = 3.13 {+-} 0.71(stat) {+-} 0.20(syst) x 10{sup -4}. This is the first observation of the antiparticle mode. Our measurement for the particle mode agrees with the previous experimental result and has an order-of-magnitude better precision. We extract the contribution from the resonance decay mode {Omega}{sup {-+}} {yields} {Xi}*{sub 1530}{sup 0} ({ovr {Xi}*{sub 1530}{sup 0}}){pi}{sup {-+}} to the final state {Xi}{sup {-+}}{pi}{sup {+-}}{pi}{sup {-+}}. This the first actual measurement of the resonance-mode branching ratios, gives B({Omega}{sup -} {yields} {Xi}*{sub 1530}{sup 0} {pi}{sup -}) = [4.55 {+-} 2.33(stat) {+-} 0.38(syst)] x 10{sup -5}, B({Omega}{sup +} {yields} {ovr {Xi}*{sub 1530}{sup 0}}{pi}{sup +}) = [1.40 {+-} 2.83(stat) {+-} 0.12(syst)] x 10{sup -5} and disagrees with the current Particle Data Group review value, being {approx} 14 times smaller. Since the central value of the resonance-mode branching ratio is less than two standard deviations away from zero, we also calculate branching ratio upper limits at 90% confidence level: B({Omega}{sup -} {yields} {Xi}*{sub 1530}{sup 0} {pi}{sup -}) < 7.61 x 10{sup -5} and B({Omega}{sup +} {yields} {ovr {Xi}*{sub 1530}{sup 0}} {pi}{sup +}) < 5.61 x 10{sup -5}. This analysis provides new data on nonleptonic hyperon decays which allows studies of how weak interaction processes occur in the presence of strong interactions.

  1. PAM stack test utility

    Energy Science and Technology Software Center (ESTSC)

    2007-08-22

    The pamtest utility calls the normal PAM hooks using a service and username supplied on the command line. This allows an administratory to test any one of many configured PAM stacks as any existing user on the machine.

  2. D0 Vent Stacks

    SciTech Connect

    Fuerst, J.D.; /Fermilab

    1988-01-22

    There are two nitrogen/argon exhaust headers in the D0 cryogenic piping system, one for the liquid argon dewar and another for the three argon calorimeters. These headers serve two functions, venting both nitrogen exhaust from the cooling loops and cold argon gas should any argon vessel blow a relief. These headers are vacuum jacketed until they exit the building. At that point, uninsulated exhaust stacks direct the flow into the atmosphere. This note deals with the these stacks.

  3. Measurement of the Ratios of Branching Fractions B(Bs -> Ds pi pi pi) / B(Bd -> Dd pi pi pi) and B(Bs -> Ds pi) / B(Bd -> Dd pi)

    SciTech Connect

    Abulencia, A.; Adelman, J.; Affolder, T.; Akimoto, T.; Albrow, M.G.; Ambrose, D.; Amerio, S.; Amidei, D.; Anastassov, A.; Anikeev, K.; Annovi, A.; /Frascati /Taiwan, Inst. Phys.

    2006-10-01

    Using 355 pb{sup -1} of data collected by the CDF II detector in p{bar p} collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron, they study the fully reconstructed hadronic decays B{sub (s)}{sup 0} {yields} D{sub (s)}{sup -}{pi}{sup +} and B{sub (s)}{sup 0} {yields} D{sub (s)}{sup -} {pi}{sup +}{pi}{sup +}{pi}{sup -}. They present the first measurement of the ratio of branching fractions {Beta}(B{sub s}{sup 0} {yields} D{sub s}{sup -}{pi}{sup +}{pi}{sup +}{pi}{sup -})/{Beta}(B{sup 0} {yields} D{sup -} {pi}{sup +}{pi}{sup +}{pi}{sup -}) = 1.05 {+-} 0.10(stat.) {+-} 0.22(syst.). They also update their measurement of {Beta}(B{sub s}{sup 0} {yields} D{sub s}{sup -} {pi}{sup +})/{Beta}(B{sup 0} {yields} D{sup -} {pi}{sup +}) to 1.13 {+-} 0.08(stat.) {+-} 0.23(syst.) improving the statistical uncertainty by more than a factor of two. They find {Beta}(B{sub s}{sup 0} {yields} D{sub s}{sup -} {pi}{sup +}) = [3.8 {+-} 0.3(stat.) {+-} 1.3(syst.)] x 10{sup -3} and {Beta}(B{sub s}{sup 0} {yields} D{sub s}{sup -} {pi}{sup +}{pi}{sup +}{pi}{sup -}) = [8.4 {+-} 0.8(stat.) {+-} 3.2(syst.)] x 10{sup -3}.

  4. Deconstruction and elastic {pi}{pi} scattering in Higgsless models

    SciTech Connect

    Chivukula, R. Sekhar; Simmons, Elizabeth H.; He, Hong-Jian; Kurachi, Masafumi; Tanabashi, Masaharu

    2007-02-01

    We study elastic pion-pion scattering in global linear moose models and apply the results to a variety of Higgsless models in flat and anti-de Sitter (AdS) space using the equivalence theorem. In order to connect the global moose to Higgsless models, we first introduce a block-spin transformation which corresponds, in the continuum, to the freedom to perform coordinate transformations in the Higgsless model. We show that it is possible to make an 'f-flat' deconstruction in which all of the f-constants f{sub j} of the linear moose model are identical; the phenomenologically relevant f-flat models are those in which the coupling constants of the groups at either end of the moose are small--corresponding to the global linear moose. In studying pion-pion scattering, we derive various sum rules, including one analogous to the Kawarabayashi-Suzuki-Riazuddin-Fayyazuddin (KSRF) relation, and use them in evaluating the low-energy and high-energy forms of the leading elastic partial-wave scattering amplitudes. We obtain elastic unitarity bounds as a function of the mass of the lightest KK mode and discuss their physical significance.

  5. Study of the D0 ---> K+ K- pi+ pi-

    SciTech Connect

    Link, J.M.; Yager, P.M.; Anjos, J.C.; Bediaga, I.; Gobel, C.; Machado, A.A.; Magnin, J.; Massafferri, A.; de Miranda, J.M.; Pepe, I.M.; Polycarpo, E.; dos Reis, A.C.; Carrillo, S.; Casimiro, E.; Cuautle, E.; Sanchez-Hernandez, A.; Uribe, C.; Vazquez, F.; Agostino, L.; Cinquini, L.; Cumalat, J.P. /Colorado U. /Fermilab /Frascati /Guanajuato U. /Illinois U., Urbana /Indiana U. /Korea U. /Kyungpook Natl. U. /INFN, Milan /Milan U. /North Carolina U. /Pavia U. /INFN, Pavia /Puerto Rico U., Mayaguez /South Carolina U. /Tennessee U. /Vanderbilt U. /Wisconsin U., Madison

    2004-11-01

    Using data from the FOCUS (E831) experiment at Fermilab, the authors present a new measurement for the Cabibbo-suppressed decay mode D{sup 0} {yields} K{sup +}K{sup -}{pi}{sup +}{pi}{sup -}. They measure: {Lambda}(D{sup 0} {yields} K{sup +}K{sup -}{pi}{sup +}{pi}{sup -})/{Lambda}(D{sup 0} {yields} K{sup -}{pi}{sup -}{pi}{sup +}{pi}{sup +}) = 0.0295 {+-} 0.0011 {+-} 0.0008. An amplitude analysis has been performed in order to determine the resonant substructure of this decay mode. The dominant components are the decays D{sup 0} {yields} K{sub 1}(1270){sup +} K{sup -}, D{sup 0} {yields} K{sub 1}(1400){sup +}K{sup -} and D{sup 0} {yields} {rho}(770){sup 0}{phi}(1020).

  6. Measurements of the branching fractions for B{sub (s)}{yields}D{sub (s)}{pi}{pi}{pi} and {Lambda}{sub b}{sup 0}{yields}{Lambda}{sub c}{sup +}{pi}{pi}{pi}

    SciTech Connect

    Aaij, R.; Bauer, Th.; Beuzekom, M. van; Carvalho Akiba, K.; Coco, V.; van Eijk, D.; Farinelli, C.; Heijne, V.; Hulsbergen, W.; Jans, E.; Jansen, F.; Koppenburg, P.; Kozlinskiy, A.; van Leerdam, J.; Merk, M.; Mous, I.; Oggero, S.; Pellegrino, A.; du Pree, T.; Storaci, B.

    2011-11-01

    Branching fractions of the decays H{sub b}{yields}H{sub c}{pi}{sup -}{pi}{sup +}{pi}{sup -} relative to H{sub b}{yields}H{sub c}{pi}{sup -} are presented, where H{sub b} (H{sub c}) represents B{sup 0} (D{sup +}), B{sup -} (D{sup 0}), B{sub s}{sup 0} (D{sub s}{sup +}), and {Lambda}{sub b}{sup 0} ({Lambda}{sub c}{sup +}). The measurements are performed with the LHCb detector using 35 pb{sup -1} of data collected at {radical}(s)=7 TeV. The ratios of branching fractions are measured to be [B(B{sup 0}{yields}D{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -})]/[B(B{sup 0}{yields}D{sup +}{pi}{sup -})]=2.38{+-}0.11{+-}0.21, [B(B{sup -}{yields}D{sup 0}{pi}{sup -}{pi}{sup +}{pi}{sup -})]/[B(B{sup -}{yields}D{sup 0}{pi}{sup -})]= 1.27{+-}0.06{+-}0.11, [B(B{sub s}{sup 0}{yields}D{sub s}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -})]/[B(B{sub s}{sup 0}{yields}D{sub s}{sup +}{pi}{sup -})]=2.01{+-}0.37{+-}0.20, [B({Lambda}{sub b}{sup 0}{yields}{Lambda}{sub c}{sup +}{pi}{sup -} {pi}{sup +}{pi}{sup -})]/[B({Lambda}{sub b}{sup 0}{yields}{Lambda}{sub c}{sup +}{pi}{sup -})]=1.43{+-}0.16{+-}0.13 We also report measurements of partial decay rates of these decays to excited charm hadrons. These results are of comparable or higher precision than existing measurements.

  7. Dalitz Plot Analysis of B- -> D+ pi- pi-

    SciTech Connect

    Aubert, : B.

    2009-01-29

    The author reports on a Dalitz plot analysis of B{sup -} {yields} D{sup +}{pi}{sup -}{pi}{sup -} decays, based on a sample of about 383 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. They find the total branching fraction of the three-body decay: {Beta}(B{sup -} {yields} D{sup +} {pi}{sup -}{pi}{sup -}) = (1.08 {+-} 0.01 {+-} 0.05) x 10{sup -3}. the masses and widths of D*{sub 2}{sup 0} and D*{sub 0}{sup 0}, the 2{sup +} and 0{sup +} c{bar u} P-wave states decaying to D{sup +}{pi}{sup -}, are measured: m{sub D*{sub 2}{sup 0}} = (2460.4 {+-} 1.2 {+-} 1.2 {+-} 1.9) MeV/c{sup 2}, {Lambda}{sub D*{sub 2}{sup 0}} = (41.8 {+-} 2.5 {+-} 2.1 {+-} 2.0) MeV, m{sub D*{sub 0}{sup 0}} = (2297 {+-} 8 {+-} 5 {+-} 19) MeV/c{sup 2} and {Lambda}{sub D*{sub 0}{sup 0}} = (273 {+-} 12 {+-} 17 {+-} 45) MeV. The stated errors reflect the statistical and systematic uncertainties, and the uncertainty related to the assumed composition of signal events and the theoretical model.

  8. Towards highly efficient red thermally activated delayed fluorescence materials by the control of intra-molecular π-π stacking interactions

    NASA Astrophysics Data System (ADS)

    Zhang, Yunge; Zhang, Dongdong; Cai, Minghan; Li, Yilang; Zhang, Deqiang; Qiu, Yong; Duan, Lian

    2016-03-01

    Thermally activated delayed fluorescence (TADF) materials have attracted much attention as they can achieve 100% theoretical internal quantum efficiency without using expensive noble metals. However, efficient red TADF emitters are hard to realize according to the energy gap law. Here, three donor-acceptor-donor type TADF emitters with the same acceptor of o-phthalodinitrile (PN) but different donors (9, 9-dimethyl-9, 10-dihydroacridine (DMAC), phenoxazine (PXZ), and phenothiazine (PTZ) for DMAC-PN, PXZ-PN, and PTZ-PN, respectively) have been synthesized, and it is observed that the performance of the emitters can be improved by reducing the intra-molecular π-π stacking. DMAC-PN with reduced intra-molecular π-π stacking shows a photoluminescence quantum yield (PLQY) of 20.2% in degassed toluene solution, much higher than those of PXZ-PN, and PTZ-PN (0.8%, 0.2%, respectively). An organic light-emitting diode (OLED) employing DMAC-PN doped into 4,4‧-bis(9H-carbazol-9-yl)biphenyl (CBP) as the emitting layer exhibits a maximum external quantum efficiency (EQE) of 10.2% with the emission peak at 564 nm. Moreover, when DMAC-PN is doped into a polar host, bis[2-(diphenylphosphino)phenyl] ether oxide (DPEPO), the OLED shows a large redshift of the emission maximum to 594 nm, while maintaining a peak EQE as high as 7.2%, indicating that efficient red TADF OLEDs can be fabricated by doping orange TADF emitters into hosts with proper polarity.

  9. Towards highly efficient red thermally activated delayed fluorescence materials by the control of intra-molecular π-π stacking interactions.

    PubMed

    Zhang, Yunge; Zhang, Dongdong; Cai, Minghan; Li, Yilang; Zhang, Deqiang; Qiu, Yong; Duan, Lian

    2016-03-01

    Thermally activated delayed fluorescence (TADF) materials have attracted much attention as they can achieve 100% theoretical internal quantum efficiency without using expensive noble metals. However, efficient red TADF emitters are hard to realize according to the energy gap law. Here, three donor-acceptor-donor type TADF emitters with the same acceptor of o-phthalodinitrile (PN) but different donors (9, 9-dimethyl-9, 10-dihydroacridine (DMAC), phenoxazine (PXZ), and phenothiazine (PTZ) for DMAC-PN, PXZ-PN, and PTZ-PN, respectively) have been synthesized, and it is observed that the performance of the emitters can be improved by reducing the intra-molecular π-π stacking. DMAC-PN with reduced intra-molecular π-π stacking shows a photoluminescence quantum yield (PLQY) of 20.2% in degassed toluene solution, much higher than those of PXZ-PN, and PTZ-PN (0.8%, 0.2%, respectively). An organic light-emitting diode (OLED) employing DMAC-PN doped into 4,4'-bis(9H-carbazol-9-yl)biphenyl (CBP) as the emitting layer exhibits a maximum external quantum efficiency (EQE) of 10.2% with the emission peak at 564 nm. Moreover, when DMAC-PN is doped into a polar host, bis[2-(diphenylphosphino)phenyl] ether oxide (DPEPO), the OLED shows a large redshift of the emission maximum to 594 nm, while maintaining a peak EQE as high as 7.2%, indicating that efficient red TADF OLEDs can be fabricated by doping orange TADF emitters into hosts with proper polarity. PMID:26821694

  10. Stack filter classifiers

    SciTech Connect

    Porter, Reid B; Hush, Don

    2009-01-01

    Just as linear models generalize the sample mean and weighted average, weighted order statistic models generalize the sample median and weighted median. This analogy can be continued informally to generalized additive modeels in the case of the mean, and Stack Filters in the case of the median. Both of these model classes have been extensively studied for signal and image processing but it is surprising to find that for pattern classification, their treatment has been significantly one sided. Generalized additive models are now a major tool in pattern classification and many different learning algorithms have been developed to fit model parameters to finite data. However Stack Filters remain largely confined to signal and image processing and learning algorithms for classification are yet to be seen. This paper is a step towards Stack Filter Classifiers and it shows that the approach is interesting from both a theoretical and a practical perspective.

  11. Barrier RF stacking

    SciTech Connect

    Chou, W.; Wildman, D.; Zheng, H.; Takagi, A.; /KEK, Tsukuba

    2004-12-01

    A novel wideband RF system, nicknamed the barrier RF, has been designed, fabricated and installed in the Fermilab Main Injector. The cavity is made of seven Finemet cores, and the modulator made of two bipolar high-voltage fast solid-state switches. The system can deliver {+-}7 kV square pulses at 90 kHz. The main application is to stack two proton batches injected from the Booster and squeeze them into the size of one so that the bunch intensity can be doubled. High intensity beams have been successfully stacked and accelerated to 120 GeV with small losses. The problem of large longitudinal emittance growth is the focus of the present study. An upgraded system with two barrier RF cavities for continuous stacking is under construction. This work is part of the US-Japan collaborative agreement.

  12. Barrier RF Stacking

    SciTech Connect

    Chou, W.; Wildman, D.; Zheng, H.; Takagi, A.

    2005-06-08

    A novel wideband RF system, nicknamed the barrier RF, has been designed, fabricated and installed in the Fermilab Main Injector. The cavity is made of seven Finemet cores, and the modulator made of two bipolar high-voltage fast solid-state switches. The system can deliver {+-}7 kV square pulses at 90 kHz. The main application is to stack two proton batches injected from the Booster and squeeze them into the size of one so that the bunch intensity can be doubled. High intensity beams have been successfully stacked and accelerated to 120 GeV with small losses. The problem of large longitudinal emittance growth is the focus of the present study. An upgraded system with two barrier RF cavities for continuous stacking is under construction. This work is part of the US-Japan collaborative agreement.

  13. Barrier RF Stacking

    NASA Astrophysics Data System (ADS)

    Chou, W.; Wildman, D.; Zheng, H.; Takagi, A.

    2005-06-01

    A novel wideband RF system, nicknamed the barrier RF, has been designed, fabricated and installed in the Fermilab Main Injector. The cavity is made of seven Finemet cores, and the modulator made of two bipolar high-voltage fast solid-state switches. The system can deliver ±7 kV square pulses at 90 kHz. The main application is to stack two proton batches injected from the Booster and squeeze them into the size of one so that the bunch intensity can be doubled. High intensity beams have been successfully stacked and accelerated to 120 GeV with small losses. The problem of large longitudinal emittance growth is the focus of the present study. An upgraded system with two barrier RF cavities for continuous stacking is under construction. This work is part of the US-Japan collaborative agreement.

  14. An atomic force microcopy study of the mechanical and electricalproperties of monolayer films of molecules with aromatic end groups

    SciTech Connect

    Fang, Liang; Park, J.Y.; Ma, H.; Jen, A.K.-Y.; Salmeron, M.

    2007-09-06

    The effect of intermolecular {pi}-{pi} stacking on the electrical and mechanical properties of monolayer films molecules containing aromatic groups was studied using atomic force microscopy. Two types of aromatic molecules, (4-mercaptophenyl) anthrylacetylene (MPAA) and (4-mercaptophenyl)-phenylacetylene (MPPA) were used as model systems with different {pi}-{pi} stacking strength. Monolayer films of these molecules on Au(111) surfaces exhibited conductivities differing by more than one order of magnitude, MPAA being the most conductive and MPPA the least conductive. The response to compressive loads by the AFM tip was also found to be very different for both molecules. In MPAA films distinct molecular conductivity changes are observed upon mechanical perturbation. This effect however was not observed on the MPPA film, where intermolecular {pi}-{pi} interactions are likely weaker.

  15. Laser pulse stacking method

    DOEpatents

    Moses, Edward I.

    1992-01-01

    A laser pulse stacking method is disclosed. A problem with the prior art has been the generation of a series of laser beam pulses where the outer and inner regions of the beams are generated so as to form radially non-synchronous pulses. Such pulses thus have a non-uniform cross-sectional area with respect to the outer and inner edges of the pulses. The present invention provides a solution by combining the temporally non-uniform pulses in a stacking effect to thus provide a more uniform temporal synchronism over the beam diameter.

  16. Laser pulse stacking method

    DOEpatents

    Moses, E.I.

    1992-12-01

    A laser pulse stacking method is disclosed. A problem with the prior art has been the generation of a series of laser beam pulses where the outer and inner regions of the beams are generated so as to form radially non-synchronous pulses. Such pulses thus have a non-uniform cross-sectional area with respect to the outer and inner edges of the pulses. The present invention provides a solution by combining the temporally non-uniform pulses in a stacking effect to thus provide a more uniform temporal synchronism over the beam diameter. 2 figs.

  17. The Search for Exotic Mesons in gamma p -> pi+pi+pi-n with CLAS at Jefferson Lab

    SciTech Connect

    Craig Bookwalter

    2011-12-01

    The {pi}{sub 1}(1600), a J{sup PC} = 1{sup {-+}} exotic meson has been observed by experiments using pion beams. Theorists predict that photon beams could produce gluonic hybrid mesons, of which the {pi}{sub 1}(1600) is a candidate, at enhanced levels relative to pion beams. The g12 rungroup at Jefferson Lab's CEBAF Large Acceptance Spectrometer (CLAS) has recently acquired a large photoproduction dataset, using a liquid hydrogen target and tagged photons from a 5.71 GeV electron beam. A partial-wave analysis of 502K {gamma}p {yields} {pi}{sup +}{pi}{sup +}{pi}{sup -}n events selected from the g12 dataset has been performed, and preliminary fit results show strong evidence for well-known states such as the a{sub 1}(1260), a{sub 2}(1320), and {pi}{sub 2}(1670). However, we observe no evidence for the production of the {pi}{sub 1}(1600) in either the partial-wave intensities or the relative complex phase between the 1{sup {-+}} and the 2{sup {-+}} (corresponding to the {pi}{sub 2}) partial waves.

  18. Measurement of CP Violation Parameters with a Dalitz Plot Analysis of B+- to D(pi+pi-pi0)K+-

    SciTech Connect

    Aubert, B.

    2007-03-28

    We report the results of a CP violation analysis of the decay B{sup {+-}} {yields} D{sub {pi}{sup +}{pi}{sup -}{pi}{sup 0}}K{sup {+-}}, where D{sub {pi}{sup +}{pi}{sup -}{pi}{sup 0}} indicates a neutral D meson detected in the final state {pi}{sup +}{pi}{sup -}{pi}{sup 0}, excluding K{sub S}{sup 0}{pi}{sup 0}. The analysis makes use of 324 million e{sup +}e{sup -} {yields} B{bar B} events recorded by the BABAR experiment at the PEP-II e{sup +}e{sup -} storage ring. By analyzing the {pi}{sup +}{pi}{sup -}{pi}{sup 0} Dalitz plot distribution and the B{sup {+-}} {yields} D{sub {pi}{sup +}{pi}{sup -}{pi}{sup 0}} K{sup {+-}} branching fraction and decay rate asymmetry, we calculate parameters related to the phase {gamma} of the CKM unitarity triangle. We also measure the magnitudes and phases of the components of the D{sup 0} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0} decay amplitude.

  19. Amplitude Analysis of the Decay $D_s^+ \\to \\pi^+ \\pi^- \\pi^+$ in the Experiment E831/FOCUS

    SciTech Connect

    Schilithz, Anderson Correa; /Rio de Janeiro, CBPF

    2005-01-01

    We present in this thesis the Dalitz Plot analysis of the D{sub s}{sup +} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup +} decay, with the data of the E831/FOCUS, that took data in 1996 and 1997. The masses and widhts of f{sub 0}(980) and f{sub 0}(1370) are free parametres of the fit on Dalitz Plot, objectiving to study in detail these resonances. After this analysis we present the Spectator Model study on the S wave in this decay. For this study we used the formalism developed by M. Svec [2] for scattering. We present the comparison between the Isobar Model, frequently used in Dalitz Plot analysis, and this formalism.

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

    SciTech Connect

    Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; Grauges, E.; Palano, A.; Pappagallo, M.; Pompili, A.; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; Eigen, G.; Ofte, I.; Stugu, B. /Bergen U. /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /Pisa U. /INFN, Pisa /Prairie View A-M /Princeton U. /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /South Carolina U. /SLAC /Oregon U. /SLAC /SLAC /Stanford U., Phys. Dept. /SUNY, Stony Brook /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Vanderbilt U. /Victoria U. /Warwick U. /Wisconsin U., Madison /Yale U.

    2005-06-10

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

  1. Search for D0--anti-D0 Mixing in the Decays D0 --> K+ pi- pi+ pi-

    SciTech Connect

    Aubert, B.

    2006-09-26

    We present a search for D{sup 0}-{bar D}{sup 0} mixing in the decays D{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} using 230.4 fb{sup -1} of data collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider at SLAC. Assuming CP conservation, we measure the time-integrated mixing rate R{sub M} = (0.019{sub -0.015}{sup +0.016}(stat.) {+-} 0.002(syst.))%, and R{sub M} < 0.048% at the 95% confidence level. Using a frequentist method, we estimate that the data are consistent with no mixing at the 4.3% confidence level. We present results both with and without the assumption of CP conservation. By combining the value of R{sub M} from this analysis with that obtained from an analysis of the decays D{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0}, we find R{sub M} = (0.020{sub -0.010}{sup +0.011})%, where the uncertainty is statistical only. We determine the upper limit R{sub M} < 0.042% at the 95% confidence level, and we find the combined data are consistent with the no-mixing hypothesis at the 2.1% confidence level.

  2. Observation of $\\Upsilon(4S) decays to$\\pi^+pi^-\\Upsilon(1S)$ and $\\pi^+pi^-\\Upsilon(1S)$

    SciTech Connect

    Aubert, B.

    2006-04-19

    The authors present the first measurement of {Upsilon}(4S) decays to {pi}{sup +}{pi}{sup -} {Upsilon}(1S) and {pi}{sup +}{pi}{sup -} {Upsilon}(2S) based on a sample of 230 x 10{sup 6} {Upsilon}(4S) mesons collected with the BABAR detector. They measure the product branching fractions {Beta}({Upsilon}(4S) {yields} {pi}{sup +}{pi}{sup -} {Upsilon}(1S)) x {Beta}({Upsilon}(1S) {yields} {mu}{sup +}{mu}{sup -}) = (2.23 {+-} 0.25{sub stat} {+-} 0.27{sub sys}) x 10{sup -6} and {Beta}({Upsilon}(4S) {yields} {pi}{sup +}{pi}{sup -}{Upsilon}(2S)) x {Beta}({Upsilon}(2S) {yields} {mu}{sup +}{mu}{sup -}) = (1.69 {+-} 0.26{sub stat} {+-} 0.20{sub sys}) x 10{sup -6}, from which they derive the partial widths {Lambda}({Upsilon}(4S) {yields} {pi}{sup +}{pi}{sup -} {Upsilon}(1S)) = (1.8 {+-} 0.4) keV and {Lambda}({Upsilon}(4S) {yields} {pi}{sup +}{pi}{sup -}{Upsilon}(2S)) = (2.7 {+-} 0.8) keV.

  3. Gene stacking by recombinases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Efficient methods of stacking genes into plant genomes are needed to expedite transfer of multigenic traits into diverse crops grown in a variety of environments. Over two decades of research has identified several site-specific recombinases that carry out efficient cis and trans recombination betw...

  4. STACK GAS REHEAT EVALUATION

    EPA Science Inventory

    The report gives results of technical and economic evaluations of stack gas reheat (SGR) following wet flue gas desulfurization (FGD) for coal-fired power plants. The evaluations were based on information from literature and a survey of FGD users, vendors, and architect/engineer ...

  5. 23. Brick coke quencher, brick stack, metal stack to right, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. Brick coke quencher, brick stack, metal stack to right, coke gas pipe to left; in background, BOF building, limestone piles, Levy's Slag Dump. Looking north/northwest - Rouge Steel Company, 3001 Miller Road, Dearborn, MI

  6. Tuning of Supramolecular Architectures of l-Valine-Containing Dicyanoplatinum(II) 2,2'-Bipyridine Complexes by Metal-Metal, π-π Stacking, and Hydrogen-Bonding Interactions.

    PubMed

    Fu, Heidi Li-Ki; Po, Charlotte; He, Hexiang; Leung, Sammual Yu-Lut; Wong, Kam Sing; Yam, Vivian Wing-Wah

    2016-08-01

    A series of newly synthesized dicyanoplatinum(II) 2,2'-bipyridine complexes exhibits self-assembly properties in solution after the incorporation of the l-valine amino units appended with various hydrophobic motifs. These l-valine-derived substituents were found to have critical control over the aggregation behaviors of the complexes in the solution state. On one hand, one of the complexes was found to exhibit interesting circularly polarized luminescence (CPL) signals at low temperature due to the formation of chiral spherical aggregates in the temperature-dependent studies. On the other hand, systematic transformation from less uniform aggregates to well-defined fibrous and rod-like structures via Pt⋅⋅⋅Pt and π-π stacking interactions has also been observed in the mixed-solvent studies. These changes were monitored by UV/Vis absorption, emission, circular dichroism (CD), and CPL spectroscopies, and morphologies were studied by electron microscopy. PMID:27412571

  7. Nonlinearly stacked low noise turbofan stator

    NASA Technical Reports Server (NTRS)

    Schuster, William B. (Inventor); Kontos, Karen B. (Inventor); Weir, Donald S. (Inventor); Nolcheff, Nick A. (Inventor); Gunaraj, John A. (Inventor)

    2009-01-01

    A nonlinearly stacked low noise turbofan stator vane having a characteristic curve that is characterized by a nonlinear sweep and a nonlinear lean is provided. The stator is in an axial fan or compressor turbomachinery stage that is comprised of a collection of vanes whose highly three-dimensional shape is selected to reduce rotor-stator and rotor-strut interaction noise while maintaining the aerodynamic and mechanical performance of the vane. The nonlinearly stacked low noise turbofan stator vane reduces noise associated with the fan stage of turbomachinery to improve environmental compatibility.

  8. Energy Expenditure of Sport Stacking

    ERIC Educational Resources Information Center

    Murray, Steven R.; Udermann, Brian E.; Reineke, David M.; Battista, Rebecca A.

    2009-01-01

    Sport stacking is an activity taught in many physical education programs. The activity, although very popular, has been studied minimally, and the energy expenditure for sport stacking is unknown. Therefore, the purposes of this study were to determine the energy expenditure of sport stacking in elementary school children and to compare that value…

  9. Iridium Interfacial Stack (IRIS)

    NASA Technical Reports Server (NTRS)

    Spry, David James (Inventor)

    2015-01-01

    An iridium interfacial stack ("IrIS") and a method for producing the same are provided. The IrIS may include ordered layers of TaSi.sub.2, platinum, iridium, and platinum, and may be placed on top of a titanium layer and a silicon carbide layer. The IrIS may prevent, reduce, or mitigate against diffusion of elements such as oxygen, platinum, and gold through at least some of its layers.

  10. Thermoacoustic Refrigerator's Stack Optimization

    NASA Astrophysics Data System (ADS)

    El-Fawal, Mawahib Hassan; Mohd-Ghazali, Normah; Yaacob, Mohd. Shafik; Darus, Amer Nordin

    2010-06-01

    The standing wave thermoacoustic refrigerator, which uses sound generation to transfer heat, was developed rapidly during the past four decades. It was regarded as a new, promising and environmentally benign alternative to conventional compression vapor refrigerators, although it was not competitive regarding the coefficient of performance (COP) yet. Thus the aim of this paper is to enhance thermoacoustic refrigerator's stack performance through optimization. A computational optimization procedure of thermoacoustic stack design was fully developed. The procedure was designed to achieve optimal coefficient of performance based on most of the design and operating parameters. Cooling load and acoustic power governing equations were set assuming the linear thermoacoustic theory. Lagrange multipliers method was used as an optimization technique tool to solve the governing equations. Numerical analyses results of the developed design procedure are presented. The results showed that the stack design parameters are the most significant parameters for the optimal overall performance. The coefficient of performance obtained increases by about 48.8% from the published experimental optimization methods. The results are in good agreement with past established studies.

  11. Structural Consequences of Anionic Host-Cationic Guest Interactions in a Supramolecular Assembly

    SciTech Connect

    Pluth, Michael D.; Johnson, Darren W.; Szigethy, Geza; Davis, Anna V.; Teat, Simon J.; Oliver, Allen G.; Bergman, Robert G.; Raymond, Kenneth N.

    2008-07-09

    The molecular structure of the self-assembled supramolecular assembly [M{sub 4}L{sub 6}]{sup 12-} has been explored with different metals (M = Ga{sup III}, Fe{sup III}, Ti{sup IV}) and different encapsulated guests (NEt{sub 4}{sup +}, BnNMe{sub 3}{sup +}, Cp{sub 2}Co{sup +}, Cp*{sub 2}Co{sup +}) by X-ray crystallography. While the identity of the metal ions at the vertices of the M{sub 4}L{sub 6} structure is found to have little effect on the assembly structure, encapsulated guests significantly distort the size and shape of the interior cavity of the assembly. Cations on the exterior of the assembly are found to interact with the assembly through either {pi}-{pi}, cation-{pi}, or CH-{pi} interactions. In some cases, the exterior guests interact with only one assembly, but cations with the ability to form multiple {pi}-{pi} interactions are able to interact with adjacent assemblies in the crystal lattice. The solvent accessible cavity of the assembly is modeled using the rolling probe method and found to range from 253-434 {angstrom}{sup 3}, depending on the encapsulated guest. Based on the volume of the guest and the volume of the cavity, the packing coefficient for each host-guest complex is found to range from 0.47-0.67.

  12. Stacking attributes from local slopes

    NASA Astrophysics Data System (ADS)

    Ghosh, S.; Gajewski, D.; Dell, S.; Nath, S. K.; Wave Inversion Technology (Wit) Consortium

    2010-12-01

    CMP stacking is controlled by the stacking velocity which is determined by a one-dimendional optimization procedure using semblance as a coherence criterion. New multi-parameter stacking formulas like the Common Reflection Surface (CRS) operator consider neighboring CMP locations in the stack. These methods stack considerably more traces than conventional CMP processing leading to stacked sections with an improved signal-to-nose ratio and better image quality. The corresponding stacking trajectories are controlled by three stacking attributes for the 2-D case and eight for the 3-D case. The determination of these attributes requires a multi-dimensional optimization procedure which is time consuming. If we know good starting values, we can limit the search intervals considerably and speed up the process. It was shown that the stacking attributes are linked to local slopes in seismic zero offset and constant offset sections. Therefore, the determination of local slopes can guide the choice of the search intervals in the optimization procedure. We use structural tensors for the determination of local slopes. Structural tensors represent a versatile tool to investigate coherent features in the data superior to other slop determination tools like slant stacking or plane wave destructors. The window size is adjustable and allows to optimize smoothing and smearing in the slope determination process where the smoothing can be performed along structural events (directional smoothing). This smart feature helps to consider complex geologies and acknowledges faults and conflicting dips without any significant change in computation time. Different variants of the algorithm are used to determine slopes in CMP gathers, stacked and time or depth migrated sections. The results of the local slope determinations are used to compute stacking attributes for the CRS method. We compare these to stacking attributes obtained from optimization. The attributes determined from local slopes

  13. The role of intermolecular interactions in the assemblies of Fe{sup II} and Co{sup II} tetrakis-isothiocyanatometalates with tris(1,10-phenanthroline)-Ru{sup II}: Crystal structures of two dual-metal assemblies featuring octahedral cationic and tetrahedral anionic modules

    SciTech Connect

    Ghazzali, Mohamed Langer, Vratislav; Ohrstroem, Lars

    2008-09-15

    Two new dual-metal assemblies: 2[Ru(phen){sub 3}]{sup 2+}.[Fe(SCN){sub 4}]{sup 2-}.2SCN{sup -}.4H{sub 2}O 1 and [Ru(phen){sub 3}]{sup 2+}.[Co(SCN){sub 4}]{sup 2-}2, (phen:1,10-phenanthroline), have been prepared and their structures were characterized by X-ray diffraction. In 1, the cationic octahedral enantiomers are arranged with a {lambda}{delta}{lambda}{delta}{lambda} sequence supported by {pi}-{pi} stacking and the anionic inorganic tetrahedral units are oriented between these stacks by interacting with the nearby water molecules through strong O-H...O and O-H...S hydrogen bonds. In 2, homochiral double helices in the b-direction are revealed, with tetrakis-isothiocyanate Co{sup II} anions arranged in the crystal to furnish one-dimensional (1D)-helical chains with S...S intermolecular interactions at 3.512(2) and 3.966(2) A supporting [Ru(phen){sub 3}]{sup 2+}{lambda}- and {delta}-helices with Ru...Ru shortest distance of 8.676(7) A. In both 1 and 2, the supramolecular assembly is maintained by C-H...S hydrogen bonds extending between the phenanthroline aromatic carbons in the cationic nodes and the sulphur atoms of the isothiocyanates anions. Analysis of S...S interactions in isothiocyanate containing compounds using Cambridge structural database (CSD) showed an angle dependence categorizing these interactions into 'type-I' and 'type-II'. - Graphical abstract: Side projection in 2 showing the crankshaft caused by S...S interactions in [Co(NCS){sub 4}]{sup 2-} in-between [Ru{sup II}(phen){sub 3}]{sup 2+} helices. Only isothiocyanates arms of [Co(NCS){sub 4}]{sup 2-} that are part of S...S interactions are shown and [Ru{sup II}(phen){sub 3}]{sup 2+} are presented as polyhedra.

  14. Barrier RF stacking

    SciTech Connect

    Weiren Chou and Akira Takagi

    2003-02-24

    This paper introduces a new method for stacking beams in the longitudinal phase space. It uses RF barriers to confine and compress beams in an accelerator, provided that the machine momentum acceptance is a few times larger than the momentum spread of the injected beam. This is the case for the Fermilab Main Injector. A barrier RF system employing Finemet cores and high-voltage solid-state switches is under construction. The goal is to double the number of protons per cycle on the production target for Run2 and NuMI experiments.

  15. Preparation and Characterization of [pi]-Stacking Quinodimethane Oligothiophenes. Predicting Semiconductor Behavior and Bandwidths from Crystal Structures and Molecular Orbital Calculations

    SciTech Connect

    Janzen, Daron E.; Burand, Michael W.; Ewbank, Paul C.; Pappenfus, Ted M.; Higuchi, Hiroyuki; da Silva, Demetrio A.; Young, Victor G.; Bredas, Jean-Luc; Mann, Kent R.

    2010-11-16

    A series of new quinodimethane-substituted terthiophene and quaterthiophene oligomers has been investigated for comparison with a previously studied quinoid oligothiophene that has demonstrated high mobilities and ambipolar transport behavior in thin-film transistor devices. Each new quinoidal thiophene derivative shows a reversible one-electron oxidation between 0.85 and 1.32 V, a quasi-reversible one-electron second oxidation between 1.37 and 1.96 V, and a reversible two-electron reduction between -0.05 and -0.23 V. The solution UV-vis-NIR spectrum of each compound is dominated by an intense epsilon congruent with 100,000 M{sup -1} cm{sup -1} low energy pi-pi transition that has a lambda(max) ranging between 648 and 790 nm. All X-ray crystal structures exhibit very planar quinoidal backbones and short intermolecular pi-stacking distances (3.335-3.492 A). Structures exhibit a single pi-stacking distance with parallel cofacial stacking (sulfur atoms of equivalent rings pointed in the same direction) or with alternating distances and antiparallel cofacial stacking (sulfur atoms of equivalent rings pointed in the opposite direction). Examples of the layered and herringbone-packing motifs are observed for both the parallel and the antiparallel cofacial stacking. Analysis of the X-ray structures and molecular orbital calculations indicates that all of these compounds have one-dimensional electronic band structures as a result of the pi-stacking. For structures with a unique pi-stacking distance, a simple geometric overlap parameter calculated from the shape of the molecule and the slip from perfect registry in the pi-stack correlates well with the transfer integrals (t) calculated using molecular orbital theory. The calculated valence (633 meV) and conduction (834 meV) bandwidths for a quinoid quaterthiophene structure are similar to those calculated for the benchmark pentacene and indicate that both hole and electron mobilities could be significant.

  16. Stacked reverberation mapping

    NASA Astrophysics Data System (ADS)

    Fine, S.; Shanks, T.; Green, P.; Kelly, B. C.; Croom, S. M.; Webster, R. L.; Berger, E.; Chornock, R.; Burgett, W. S.; Chambers, K. C.; Kaiser, N.; Price, P. A.

    2013-07-01

    Over the past 20 years reverberation mapping has proved one of the most successful techniques for studying the local (<1 pc) environment of supermassive black holes that drive active galactic nuclei. Key successes of reverberation mapping have been direct black hole mass estimates, the radius-luminosity relation for the Hβ line and the calibration of single-epoch mass estimators commonly employed up to z ˜ 7. However, observing constraints mean that few studies have been successful at z > 0.1, or for the more-luminous quasars that make up the majority of current spectroscopic samples, or for rest-frame ultraviolet emission lines available in optical spectra of z > 0.5 objects. Previously, we described a technique for stacking cross-correlations to obtain reverberation mapping results at high z. Here, we present the first results from a campaign designed for this purpose. We construct stacked cross-correlation functions for the C IV and Mg II lines and find a clear peak in both. We find that the peak in the Mg II correlation is at longer lags than C IV consistent with previous results at low redshift. For the C IV sample, we are able to bin by luminosity and find evidence for increasing lags for more-luminous objects. This C IV radius-luminosity relation is consistent with previous studies but with a fraction of the observational cost.

  17. Asymmetric Flexible Supercapacitor Stack

    PubMed Central

    2008-01-01

    Electrical double layer supercapacitor is very significant in the field of electrical energy storage which can be the solution for the current revolution in the electronic devices like mobile phones, camera flashes which needs flexible and miniaturized energy storage device with all non-aqueous components. The multiwalled carbon nanotubes (MWNTs) have been synthesized by catalytic chemical vapor deposition technique over hydrogen decrepitated Mischmetal (Mm) based AB3alloy hydride. The polymer dispersed MWNTs have been obtained by insitu polymerization and the metal oxide/MWNTs were synthesized by sol-gel method. Morphological characterizations of polymer dispersed MWNTs have been carried out using scanning electron microscopy (SEM), transmission electron microscopy (TEM and HRTEM). An assymetric double supercapacitor stack has been fabricated using polymer/MWNTs and metal oxide/MWNTs coated over flexible carbon fabric as electrodes and nafion®membrane as a solid electrolyte. Electrochemical performance of the supercapacitor stack has been investigated using cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy.

  18. Stacked Extreme Learning Machines.

    PubMed

    Zhou, Hongming; Huang, Guang-Bin; Lin, Zhiping; Wang, Han; Soh, Yeng Chai

    2015-09-01

    Extreme learning machine (ELM) has recently attracted many researchers' interest due to its very fast learning speed, good generalization ability, and ease of implementation. It provides a unified solution that can be used directly to solve regression, binary, and multiclass classification problems. In this paper, we propose a stacked ELMs (S-ELMs) that is specially designed for solving large and complex data problems. The S-ELMs divides a single large ELM network into multiple stacked small ELMs which are serially connected. The S-ELMs can approximate a very large ELM network with small memory requirement. To further improve the testing accuracy on big data problems, the ELM autoencoder can be implemented during each iteration of the S-ELMs algorithm. The simulation results show that the S-ELMs even with random hidden nodes can achieve similar testing accuracy to support vector machine (SVM) while having low memory requirements. With the help of ELM autoencoder, the S-ELMs can achieve much better testing accuracy than SVM and slightly better accuracy than deep belief network (DBN) with much faster training speed. PMID:25361517

  19. Can Dispersion Forces Govern Aromatic Stacking in an Organic Solvent?

    PubMed

    Yang, Lixu; Brazier, John B; Hubbard, Thomas A; Rogers, David M; Cockroft, Scott L

    2016-01-18

    Experimental support for the dominance of van der Waals dispersion forces in aromatic stacking interactions occurring in organic solution is surprisingly limited. The size-dependence of aromatic stacking in an organic solvent was examined. The interaction energy was found to vary by about 7.5 kJ mol(-1) on going from a phenyl-phenyl to an anthracene-pyrene stack. Strikingly, the experimental data were highly correlated with dispersion energies determined using symmetry-adapted perturbation theory (SAPT), while the induction, exchange, electrostatic, and solvation energy components correlated poorly. Both the experimental data and the SAPT-dispersion energies gave high-quality correlations with the change in solvent accessible area upon complexation. Thus, the size-dependence of aromatic stacking interactions is consistent with the dominance of van der Waals dispersion forces even in the presence of a competing polarizable solvent. PMID:26632979

  20. Stacked insulator induction accelerator gaps

    SciTech Connect

    Houck, T.I.; Westenskow, G.A.; Kim, J.S.; Eylon, S.; Henestroza, E.; Yu, S.S.; Vanecek, D.

    1997-05-01

    Stacked insulators, with alternating layers of insulating material and conducting film, have been shown to support high surface electrical field stresses. We have investigated the application of the stacked insulator technology to the design of induction accelerator modules for the Relativistic-Klystron Two-Beam Accelerator program. The rf properties of the accelerating gaps using stacked insulators, particularly the impedance at frequencies above the beam pipe cutoff frequency, are investigated. Low impedance is critical for Relativistic-Klystron Two-Beam Accelerator applications where a high current, bunched beam is trsnsported through many accelerating gaps. An induction accelerator module designs using a stacked insulator is presented.

  1. Thermoacoustic pin stacks. Summary report

    SciTech Connect

    Keolian, R.M.

    1994-07-06

    The construction and testing of a new stack geometry for thermoacoustic engines, called a pin stack, has been started. The stack is at the heart of a class of heat engines that use sound to deliver refrigeration, or use a temperature difference to generate sound. Calculations show that the pin stack should make useful improvements in engine efficiency. About 2000 wires will be hand sewn in a hexagonal lattice between the hot and cold heat exchangers in a sound source using low pressure neon gas between 300 K and 77 K. Thermoacoustics, Refrigeration, Acoustic source, Heat pump.

  2. The LSST Software Stack

    NASA Astrophysics Data System (ADS)

    Jenness, Timothy; LSST Data Management Team

    2016-01-01

    The Large Synoptic Survey Telescope (LSST) is an 8-m optical ground-based telescope being constructed on Cerro Pachon in Chile. LSST will survey half the sky every few nights in six optical bands. The data will be transferred to the data center in North America and within 60 seconds it will be reduced using difference imaging and an alert list be generated for the community. Additionally, annual data releases will be constructed from all the data during the 10-year mission, producing catalogs and deep co-added images with unprecedented time resolution for such a large region of sky. In the paper we present the current status of the LSST stack including the data processing components, Qserv database and data visualization software, describe how to obtain it, and provide a summary of the development road map.

  3. Stack Trace Analysis Tool

    Energy Science and Technology Software Center (ESTSC)

    2008-01-16

    STAT is a light weight debugging tool that gathers and merges stack traces from all of the processes in a parallel application. STAT uses the MRNet free based overlay network to broadcast commands from the tool front-end to the STAT daemons and for the front-end to gather the traces from the STAT daemons. As the traces propagate through the MRNet network tree, they are merged across all tasks to form a single call prefix tree.more » The call prefix tree can be examined to identify tasks with similar function call patterns and to delineate a small set of equivalence classes. A representative task from each of these classes can then be fed into a full feature debugger like TotalView for root cause analysis.« less

  4. Stack Trace Analysis Tool

    Energy Science and Technology Software Center (ESTSC)

    2013-02-19

    STAT is a light weight debugging tool that gathers and merges stack traces from all of the processes in a parallell application. STAT uses the MRNet tree based overlay network to broadcast commands from the tool front-end to the STAT daemons and for the front-end to gather the traces from the STAT daemons. As the traces propagate through the MRNet network tree, they are merged across all tasks to from a single call prefix tree.more » The call prefix tree can be examined to identify tasks with similar function call patterns and to delineate a small set of equivalence slasses. A representative task from each of these classes can then be fed into a full feature debugger like TotalView for root cause analysis.« less

  5. Stack Trace Analysis Tool

    SciTech Connect

    2013-02-19

    STAT is a light weight debugging tool that gathers and merges stack traces from all of the processes in a parallell application. STAT uses the MRNet tree based overlay network to broadcast commands from the tool front-end to the STAT daemons and for the front-end to gather the traces from the STAT daemons. As the traces propagate through the MRNet network tree, they are merged across all tasks to from a single call prefix tree. The call prefix tree can be examined to identify tasks with similar function call patterns and to delineate a small set of equivalence slasses. A representative task from each of these classes can then be fed into a full feature debugger like TotalView for root cause analysis.

  6. Stack Trace Analysis Tool

    SciTech Connect

    2008-01-16

    STAT is a light weight debugging tool that gathers and merges stack traces from all of the processes in a parallel application. STAT uses the MRNet free based overlay network to broadcast commands from the tool front-end to the STAT daemons and for the front-end to gather the traces from the STAT daemons. As the traces propagate through the MRNet network tree, they are merged across all tasks to form a single call prefix tree. The call prefix tree can be examined to identify tasks with similar function call patterns and to delineate a small set of equivalence classes. A representative task from each of these classes can then be fed into a full feature debugger like TotalView for root cause analysis.

  7. Zigzag stacks and m-regular linear stacks.

    PubMed

    Chen, William Y C; Guo, Qiang-Hui; Sun, Lisa H; Wang, Jian

    2014-12-01

    The contact map of a protein fold is a graph that represents the patterns of contacts in the fold. It is known that the contact map can be decomposed into stacks and queues. RNA secondary structures are special stacks in which the degree of each vertex is at most one and each arc has length of at least two. Waterman and Smith derived a formula for the number of RNA secondary structures of length n with exactly k arcs. Höner zu Siederdissen et al. developed a folding algorithm for extended RNA secondary structures in which each vertex has maximum degree two. An equation for the generating function of extended RNA secondary structures was obtained by Müller and Nebel by using a context-free grammar approach, which leads to an asymptotic formula. In this article, we consider m-regular linear stacks, where each arc has length at least m and the degree of each vertex is bounded by two. Extended RNA secondary structures are exactly 2-regular linear stacks. For any m ≥ 2, we obtain an equation for the generating function of the m-regular linear stacks. For given m, we deduce a recurrence relation and an asymptotic formula for the number of m-regular linear stacks on n vertices. To establish the equation, we use the reduction operation of Chen, Deng, and Du to transform an m-regular linear stack to an m-reduced zigzag (or alternating) stack. Then we find an equation for m-reduced zigzag stacks leading to an equation for m-regular linear stacks. PMID:25455155

  8. Assessing Elementary Algebra with STACK

    ERIC Educational Resources Information Center

    Sangwin, Christopher J.

    2007-01-01

    This paper concerns computer aided assessment (CAA) of mathematics in which a computer algebra system (CAS) is used to help assess students' responses to elementary algebra questions. Using a methodology of documentary analysis, we examine what is taught in elementary algebra. The STACK CAA system, http://www.stack.bham.ac.uk/, which uses the CAS…

  9. Thermal dileptons from {pi}-{rho} interactions in a hot pion gas

    SciTech Connect

    Baier, R.; Dirks, M.; Redlich, K. |

    1997-04-01

    The production of low mass dileptons from {pi}-{rho} interactions in a hot medium is studied. Applying finite temperature perturbation theory the dilepton rate is computed up to order g{sub {rho}}{sup 2}. For dilepton masses below the {rho} the two-body reactions {pi}{pi}{r_arrow}{rho}{gamma}{sup {asterisk}}, {pi}{rho}{r_arrow}{pi}{gamma}{sup {asterisk}}, and the decay process {rho}{r_arrow}{pi}{pi}{gamma}{sup {asterisk}} give significant contributions. Nonequilibrium contributions to the thermal rate are estimated, including the modification of the particle distribution function with a nonzero pion chemical potential. A comparison of the dilepton rate with the recent data measured in nucleus-nucleus collisions at CERN SPS energy by the CERES Collaboration is also performed. It is shown that the additional thermal dileptons from {pi}-{rho} interactions can partially account for the excess of the soft dilepton yield seen experimentally. {copyright} {ital 1997} {ital The American Physical Society}

  10. 49 CFR 178.815 - Stacking test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Stacking test. 178.815 Section 178.815... Stacking test. (a) General. The stacking test must be conducted for the qualification of all IBC design types intended to be stacked. (b) Special preparation for the stacking test. (1) All IBCs...

  11. Ribosomes in a Stacked Array

    PubMed Central

    Yamashita, Yui; Kadokura, Yoshitomo; Sotta, Naoyuki; Fujiwara, Toru; Takigawa, Ichigaku; Satake, Akiko; Onouchi, Hitoshi; Naito, Satoshi

    2014-01-01

    Expression of CGS1, which codes for an enzyme of methionine biosynthesis, is feedback-regulated by mRNA degradation in response to S-adenosyl-l-methionine (AdoMet). In vitro studies revealed that AdoMet induces translation arrest at Ser-94, upon which several ribosomes stack behind the arrested one, and mRNA degradation occurs at multiple sites that presumably correspond to individual ribosomes in a stacked array. Despite the significant contribution of stacked ribosomes to inducing mRNA degradation, little is known about the ribosomes in the stacked array. Here, we assigned the peptidyl-tRNA species of the stacked second and third ribosomes to their respective codons and showed that they are arranged at nine-codon intervals behind the Ser-94 codon, indicating tight stacking. Puromycin reacts with peptidyl-tRNA in the P-site, releasing the nascent peptide as peptidyl-puromycin. This reaction is used to monitor the activity of the peptidyltransferase center (PTC) in arrested ribosomes. Puromycin reaction of peptidyl-tRNA on the AdoMet-arrested ribosome, which is stalled at the pre-translocation step, was slow. This limited reactivity can be attributed to the peptidyl-tRNA occupying the A-site at this step rather than to suppression of PTC activity. In contrast, puromycin reactions of peptidyl-tRNA with the stacked second and third ribosomes were slow but were not as slow as pre-translocation step ribosomes. We propose that the anticodon end of peptidyl-tRNA resides in the A-site of the stacked ribosomes and that the stacked ribosomes are stalled at an early step of translocation, possibly at the P/E hybrid state. PMID:24652291

  12. [2,5-Bis(2,2'-bipyridyl-6-yl)-3,4-diazahexa-2,4-diene]dichloridomanganese(II): from a mononuclear compound to a three-dimensional supramolecular framework through C-H···Cl hydrogen bonds and π-π stacking interactions.

    PubMed

    Lu, Zhengliang; Zhao, Yuanchao; Chen, Baolian; Huang, Ximing; Fan, Chunhua

    2014-07-01

    The title compound, [MnCl2(C24H20N6)], has been synthesized and characterized based on the multifunctional ligand 2,5-bis(2,2'-bipyridyl-6-yl)-3,4-diazahexa-2,4-diene (L). The Mn(II) centre is five-coordinate with an approximately square-pyramidal geometry. The L ligand acts as a tridendate chelating ligand. The mononuclear molecules are bridged into a one-dimensional chain by two C-H···Cl hydrogen bonds. These chains are assembled into a two-dimensional layer through π-π stacking interactions between adjacent uncoordinated bipyridyl groups. Furthermore, a three-dimensional supramolecular framework is attained through π-π stacking interactions between adjacent coordinated bipyridyl groups. PMID:24992119

  13. Extremely strong tubular stacking of aromatic oligoamide macrocycles

    SciTech Connect

    Kline, Mark A.; Wei, Xiaoxi; Horner, Ian J.; Liu, Rui; Chen, Shuang; Chen, Si; Yung, Ka Yi; Yamato, Kazuhiro; Cai, Zhonghou; Bright, Frank V.; Zeng, Xiao Cheng; Gong, Bing

    2015-01-01

    As the third-generation rigid macrocycles evolved from progenitor 1, cyclic aromatic oligoamides 3, with a backbone of reduced constraint, exhibit extremely strong stacking with an astoundingly high affinity (estimated lower limit of Kdimer > 1013 M-1 in CHCl3), which leads to dispersed tubular stacks that undergo further assembly in solution. Computational study reveals a very large binding energy (-49.77 kcal mol-1) and indicates highly cooperative local dipole interactions that account for the observed strength and directionality for the stacking of 3. In the solid-state, X-ray diffraction (XRD) confirms that the aggregation of 3 results in well-aligned tubular stacks. The persistent tubular assemblies of 3, with their non-deformable sub-nm pore, are expected to possess many interesting functions. One such function, transmembrane ion transport, is observed for 3.

  14. Extremely strong tubular stacking of aromatic oligoamide macrocycles

    SciTech Connect

    Kline, Mark A.; Wei, Xiaoxi; Horner, Ian J.; Liu, Rui; Chen, Shuang; Chen, Si; Yung, Ka Yi; Yamato, Kazuhiro; Cai, Zhonghou; Bright, Frank V.; Zeng, Xiao Cheng; Gong, Bing

    2014-09-16

    As the third-generation rigid macrocycles evolved from progenitor 1, cyclic aromatic oligoamides 3, with a backbone of reduced constraint, exhibit extremely strong stacking with an astoundingly high affinity (estimated lower limit of K-dimer > 1013 M-1 in CHCl3), which leads to dispersed tubular stacks that undergo further assembly in solution. Computational study reveals a very large binding energy (-49.77 kcal mol-1) and indicates highly cooperative local dipole interactions that account for the observed strength and directionality for the stacking of 3. In the solid-state, X-ray diffraction (XRD) confirms that the aggregation of 3 results in well-aligned tubular stacks. Furthermore, the persistent tubular assemblies of 3, with their non-deformable sub-nm pore, are expected to possess many interesting functions. One such function, transmembrane ion transport, is observed for 3.

  15. Extremely strong tubular stacking of aromatic oligoamide macrocycles

    DOE PAGESBeta

    Kline, Mark A.; Wei, Xiaoxi; Horner, Ian J.; Liu, Rui; Chen, Shuang; Chen, Si; Yung, Ka Yi; Yamato, Kazuhiro; Cai, Zhonghou; Bright, Frank V.; et al

    2014-09-16

    As the third-generation rigid macrocycles evolved from progenitor 1, cyclic aromatic oligoamides 3, with a backbone of reduced constraint, exhibit extremely strong stacking with an astoundingly high affinity (estimated lower limit of K-dimer > 1013 M-1 in CHCl3), which leads to dispersed tubular stacks that undergo further assembly in solution. Computational study reveals a very large binding energy (-49.77 kcal mol-1) and indicates highly cooperative local dipole interactions that account for the observed strength and directionality for the stacking of 3. In the solid-state, X-ray diffraction (XRD) confirms that the aggregation of 3 results in well-aligned tubular stacks. Furthermore, themore » persistent tubular assemblies of 3, with their non-deformable sub-nm pore, are expected to possess many interesting functions. One such function, transmembrane ion transport, is observed for 3.« less

  16. Extremely strong tubular stacking of aromatic oligoamide macrocycles

    DOE PAGESBeta

    Kline, Mark A.; Wei, Xiaoxi; Horner, Ian J.; Liu, Rui; Chen, Shuang; Chen, Si; Yung, Ka Yi; Yamato, Kazuhiro; Cai, Zhonghou; Bright, Frank V.; et al

    2015-01-01

    As the third-generation rigid macrocycles evolved from progenitor 1, cyclic aromatic oligoamides 3, with a backbone of reduced constraint, exhibit extremely strong stacking with an astoundingly high affinity (estimated lower limit of Kdimer > 1013 M-1 in CHCl3), which leads to dispersed tubular stacks that undergo further assembly in solution. Computational study reveals a very large binding energy (-49.77 kcal mol-1) and indicates highly cooperative local dipole interactions that account for the observed strength and directionality for the stacking of 3. In the solid-state, X-ray diffraction (XRD) confirms that the aggregation of 3 results in well-aligned tubular stacks. The persistentmore » tubular assemblies of 3, with their non-deformable sub-nm pore, are expected to possess many interesting functions. One such function, transmembrane ion transport, is observed for 3.« less

  17. Mechanical Stiffening of Porphyrin Nanorings through Supramolecular Columnar Stacking

    PubMed Central

    2013-01-01

    Solvent-induced aggregates of nanoring cyclic polymers may be transferred by electrospray deposition to a surface where they adsorb as three-dimensional columnar stacks. The observed stack height varies from single rings to four stacked rings with a layer spacing of 0.32 ± 0.04 nm as measured using scanning tunneling microscopy. The flexibility of the nanorings results in distortions from a circular shape, and we show, through a comparison with Monte Carlo simulations, that the bending stiffness increases linearly with the stack height. Our results show that noncovalent interactions may be used to control the shape and mechanical properties of artificial macromolecular aggregates offering a new route to solvent-induced control of two-dimensional supramolecular organization. PMID:23789845

  18. Full Piezoelectric Multilayer-Stacked Hybrid Actuation/Transduction Systems

    NASA Technical Reports Server (NTRS)

    Su, Ji; Jiang, Xiaoning; Zu, Tian-Bing

    2011-01-01

    The Stacked HYBATS (Hybrid Actuation/Transduction system) demonstrates significantly enhanced electromechanical performance by using the cooperative contributions of the electromechanical responses of multilayer, stacked negative strain components and positive strain components. Both experimental and theoretical studies indicate that, for Stacked HYBATS, the displacement is over three times that of a same-sized conventional flextensional actuator/transducer. The coupled resonance mode between positive strain and negative strain components of Stacked HYBATS is much stronger than the resonance of a single element actuation only when the effective lengths of the two kinds of elements match each other. Compared with the previously invented hybrid actuation system (HYBAS), the multilayer Stacked HYBATS can be designed to provide high mechanical load capability, low voltage driving, and a highly effective piezoelectric constant. The negative strain component will contract, and the positive strain component will expand in the length directions when an electric field is applied on the device. The interaction between the two elements makes an enhanced motion along the Z direction for Stacked-HYBATS. In order to dominate the dynamic length of Stacked-HYBATS by the negative strain component, the area of the cross-section for the negative strain component will be much larger than the total cross-section areas of the two positive strain components. The transverse strain is negative and longitudinal strain positive in inorganic materials, such as ceramics/single crystals. Different piezoelectric multilayer stack configurations can make a piezoelectric ceramic/single-crystal multilayer stack exhibit negative strain or positive strain at a certain direction without increasing the applied voltage. The difference of this innovation from the HYBAS is that all the elements can be made from one-of-a-kind materials. Stacked HYBATS can provide an extremely effective piezoelectric

  19. Lateral excitonic switching in vertically stacked quantum dots

    NASA Astrophysics Data System (ADS)

    Jarzynka, Jarosław R.; McDonald, Peter G.; Shumway, John; Galbraith, Ian

    2016-06-01

    We show that the application of a vertical electric field to the Coulomb interacting system in stacked quantum dots leads to a 90° in-plane switching of charge probability distribution in contrast to a single dot, where no such switching exists. Results are obtained using path integral quantum Monte Carlo with realistic dot geometry, alloy composition, and piezo-electric potential profiles. The origin of the switching lies in the strain interactions between the stacked dots hence the need for more than one layer of dots. The lateral polarization and electric field dependence of the radiative lifetimes of the excitonic switch are also discussed.

  20. 49 CFR 178.1055 - Stacking test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Stacking test. 178.1055 Section 178.1055... Containers § 178.1055 Stacking test. (a) General. The stacking test must be conducted for the qualification of all Flexible Bulk Containers design types. (b) Special preparation for the stacking test....

  1. Fuel cell stack compressive loading system

    DOEpatents

    Fahle, Ronald W.; Reiser, Carl A.

    1982-01-01

    A fuel cell module comprising a stack of fuel cells with reactant gas manifolds sealed against the external surfaces of the stack includes a constraint system for providing a compressive load on the stack wherein the constraint system maintains the stack at a constant height (after thermal expansion) and allows the compressive load to decrease with time as a result of the creep characteristics of the stack. Relative motion between the manifold sealing edges and the stack surface is virtually eliminated by this constraint system; however it can only be used with a stack having considerable resiliency and appropriate thermal expansion and creep characteristics.

  2. Slippage in stacking of graphene nanofragments induced by spin polarization

    NASA Astrophysics Data System (ADS)

    Lei, Yanyu; Jiang, Wanrun; Dai, Xing; Song, Ruixia; Wang, Bo; Gao, Yang; Wang, Zhigang

    2015-06-01

    Spin polarization and stacking are interesting effects in complex molecular systems and are both presented in graphene-based materials. Their possible combination may provide a new perspective in understanding the intermolecular force. The nanoscale graphene structures with zigzag edges could possess spin-polarized ground states. However, the mechanical effect of spin polarization in stacking of graphene nanofragments is not clear. Here we demonstrate the displacement between two stacked rhombic graphene nanofragments induced by spin polarization, using first-principles density-functional methods. We found that, in stacking of two rhombic graphene nanofragments, a spin-polarized stacked conformation with zero total spin is energetically more favorable than the closed-shell stacking. The spin-polarized conformation gives a further horizontal interlayer displacement within 1 angstrom compared with the closed-shell structure. This result highlights that, besides the well-known phenomenologically interpreted van der Waals forces, a specific mechanism dependent on the monomeric spin polarization may lead to obvious mechanical effects in some intermolecular interactions.

  3. Slippage in stacking of graphene nanofragments induced by spin polarization.

    PubMed

    Lei, Yanyu; Jiang, Wanrun; Dai, Xing; Song, Ruixia; Wang, Bo; Gao, Yang; Wang, Zhigang

    2015-01-01

    Spin polarization and stacking are interesting effects in complex molecular systems and are both presented in graphene-based materials. Their possible combination may provide a new perspective in understanding the intermolecular force. The nanoscale graphene structures with zigzag edges could possess spin-polarized ground states. However, the mechanical effect of spin polarization in stacking of graphene nanofragments is not clear. Here we demonstrate the displacement between two stacked rhombic graphene nanofragments induced by spin polarization, using first-principles density-functional methods. We found that, in stacking of two rhombic graphene nanofragments, a spin-polarized stacked conformation with zero total spin is energetically more favorable than the closed-shell stacking. The spin-polarized conformation gives a further horizontal interlayer displacement within 1 angstrom compared with the closed-shell structure. This result highlights that, besides the well-known phenomenologically interpreted van der Waals forces, a specific mechanism dependent on the monomeric spin polarization may lead to obvious mechanical effects in some intermolecular interactions. PMID:26078005

  4. Single-molecule dissection of stacking forces in DNA.

    PubMed

    Kilchherr, Fabian; Wachauf, Christian; Pelz, Benjamin; Rief, Matthias; Zacharias, Martin; Dietz, Hendrik

    2016-09-01

    We directly measured at the single-molecule level the forces and lifetimes of DNA base-pair stacking interactions for all stack sequence combinations. Our experimental approach combined dual-beam optical tweezers with DNA origami components to allow positioning of blunt-end DNA helices so that the weak stacking force could be isolated. Base-pair stack arrays that lacked a covalent backbone connection spontaneously dissociated at average rates ranging from 0.02 to 500 per second, depending on the sequence combination and stack array size. Forces in the range from 2 to 8 piconewtons that act along the helical direction only mildly accelerated the stochastic unstacking process. The free-energy increments per stack that we estimate from the measured forward and backward kinetic rates ranged from -0.8 to -3.4 kilocalories per mole, depending on the sequence combination. Our data contributes to understanding the mechanics of DNA processing in biology, and it is helpful for designing the kinetics of DNA-based nanoscale devices according to user specifications. PMID:27609897

  5. Split stack blowout prevention system

    SciTech Connect

    Crager, B.L.; Ray, D.R.; Steddum, R.E.

    1980-03-18

    A blowout prevention system for an offshore structure positioned on the underwater bottom in a body of water which contains moving ice masses that could force the structure off location wherein a surface blowout preventer stack for conventional well control is connected to the upper end of a riser with the lower end of the riser being disconnectably connected to a subsurface blowout preventer stack which provides the necessary well control should the structure be forced off location. The subsurface stack is positioned on a wellhead located in a chamber in the subsea bottom and is disconnectably connected to the riser so that the riser may be quickly removed from the subsea bottom should the structure be forced off location.

  6. A Cloudy Quark Bag Model of S, P, and D wave interactions for the coupled channel antikaon-nucleon system

    SciTech Connect

    He, Guangliang.

    1992-05-15

    The Cloudy Quark Bag Model is extended from S-wave to P- and D-wave. The parameters of the model are determined by K{sup {minus}}p scattering cross section data, K{sup {minus}}p {yields}{Sigma}{pi}{pi}{pi} production data, K{sup {minus}}p threshold branching ratio data, and K{sup {minus}}p {yields}{Lambda}{pi}{pi}{pi} production data. The resonance structure of the {Lambda}(1405), {Sigma}(1385), and {Lambda}(1520) are studied in the model. The shift and width of kaonic hydrogen are calculated using the model.

  7. Anharmonic stacking in supercoiled DNA

    NASA Astrophysics Data System (ADS)

    Zoli, Marco

    2012-05-01

    Multistep denaturation in a short circular DNA molecule is analyzed by a mesoscopic Hamiltonian model which accounts for the helicoidal geometry. Computation of melting profiles by the path integral method suggests that stacking anharmonicity stabilizes the double helix against thermal disruption of the hydrogen bonds. Twisting is essential in the model to capture the importance of nonlinear effects on the thermodynamical properties. In a ladder model with zero twist, anharmonic stacking scarcely affects the thermodynamics. Moderately untwisted helices, with respect to the equilibrium conformation, show an energetic advantage against the overtwisted ones. Accordingly moderately untwisted helices better sustain local fluctuational openings and make more unlikely the thermally driven complete strand separation.

  8. Final state interactions and CP violation in B decays to three pseudoscalars

    SciTech Connect

    Kaminski, Robert; Lesniak, L.; Bennich, B. El; Furman, A.; Moussallam, B.

    2010-08-05

    We study CP violation and final state interactions between pions and kaons in B{sup +}, B{sup -}, -B{sup 0} and B-bar{sup 0} decays into K{pi}{pi}. The weak transition amplitudes consist of two terms: the first part is derived in QCD factorization approach and the second one is a phenomenological long-distance charming penguin contribution. The final state K{pi} interactions in S- and P-waves are described by strange scalar and vector form factors, respectively. These are determined using a unitary coupled channel model together with chiral symmetry and asymptotic QCD constraints. The final state interactions are dominated by presence of the scalar K{sub 0}*(1430) and the vector K*(892) resonances. We show that additional charming penguin amplitudes are needed to reproduce the latest experimental K{pi} effective mass and helicity angle distributions, branching fractions and asymmetries obtained by Belle and BaBar collaborations.

  9. Pressurized electrolysis stack with thermal expansion capability

    DOEpatents

    Bourgeois, Richard Scott

    2015-07-14

    The present techniques provide systems and methods for mounting an electrolyzer stack in an outer shell so as to allow for differential thermal expansion of the electrolyzer stack and shell. Generally, an electrolyzer stack may be formed from a material with a high coefficient of thermal expansion, while the shell may be formed from a material having a lower coefficient of thermal expansion. The differences between the coefficients of thermal expansion may lead to damage to the electrolyzer stack as the shell may restrain the thermal expansion of the electrolyzer stack. To allow for the differences in thermal expansion, the electrolyzer stack may be mounted within the shell leaving a space between the electrolyzer stack and shell. The space between the electrolyzer stack and the shell may be filled with a non-conductive fluid to further equalize pressure inside and outside of the electrolyzer stack.

  10. Multibeam collimator uses prism stack

    NASA Technical Reports Server (NTRS)

    Minott, P. O.

    1981-01-01

    Optical instrument creates many divergent light beams for surveying and machine element alignment applications. Angles and refractive indices of stack of prisms are selected to divert incoming laser beam by small increments, different for each prism. Angles of emerging beams thus differ by small, precisely-controlled amounts. Instrument is nearly immune to vibration, changes in gravitational force, temperature variations, and mechanical distortion.

  11. STACK SAMPLING FOR ORGANIC EMISSIONS

    EPA Science Inventory

    The paper reviews some of the more important principles involved in stack sampling for organics, briefly describes and discusses recently developed equipment, and points out a few of the more serious pitfalls. Extensive references are provided, many of which are often overlooked ...

  12. Multilayer Piezoelectric Stack Actuator Characterization

    NASA Technical Reports Server (NTRS)

    Sherrit, Stewart; Jones, Christopher M.; Aldrich, Jack B.; Blodget, Chad; Bao, Xioaqi; Badescu, Mircea; Bar-Cohen, Yoseph

    2008-01-01

    Future NASA missions are increasingly seeking to use actuators for precision positioning to accuracies of the order of fractions of a nanometer. For this purpose, multilayer piezoelectric stacks are being considered as actuators for driving these precision mechanisms. In this study, sets of commercial PZT stacks were tested in various AC and DC conditions at both nominal and extreme temperatures and voltages. AC signal testing included impedance, capacitance and dielectric loss factor of each actuator as a function of the small-signal driving sinusoidal frequency, and the ambient temperature. DC signal testing includes leakage current and displacement as a function of the applied DC voltage. The applied DC voltage was increased to over eight times the manufacturers' specifications to investigate the correlation between leakage current and breakdown voltage. Resonance characterization as a function of temperature was done over a temperature range of -180C to +200C which generally exceeded the manufacturers' specifications. In order to study the lifetime performance of these stacks, five actuators from one manufacturer were driven by a 60volt, 2 kHz sine-wave for ten billion cycles. The tests were performed using a Lab-View controlled automated data acquisition system that monitored the waveform of the stack electrical current and voltage. The measurements included the displacement, impedance, capacitance and leakage current and the analysis of the experimental results will be presented.

  13. Progress Update: Stack Project Complete

    ScienceCinema

    Cody, Tom

    2012-06-14

    Progress update from the Savannah River Site. The 75 foot 293 F Stack, built for plutonium production, was cut down to size in order to prevent injury or release of toxic material if the structure were to collapse due to harsh weather.

  14. Progress Update: Stack Project Complete

    SciTech Connect

    Cody, Tom

    2010-01-01

    Progress update from the Savannah River Site. The 75 foot 293 F Stack, built for plutonium production, was cut down to size in order to prevent injury or release of toxic material if the structure were to collapse due to harsh weather.

  15. POLYMERIC INTERFACES FOR STACK MONITORING

    EPA Science Inventory

    Research has been performed on the use of polymeric interfaces for in situ continuous stack monitoring of gaseous pollutants. Permeabilities of candidate interface materials to SO2 were measured at temperatures from ambient to 200C, and the results were used to design interfaces ...

  16. Investigation of the effect of shunt current on battery efficiency and stack temperature in vanadium redox flow battery

    NASA Astrophysics Data System (ADS)

    Tang, Ao; McCann, John; Bao, Jie; Skyllas-Kazacos, Maria

    2013-11-01

    In vanadium redox flow batteries (VFB), the power of the battery is determined by the number of cells in the stack. Serial and parallel layouts are commonly adopted interactively to suit the designed power demand. The bipolar stack design inevitably introduces shunt currents bypassing into the common manifolds in the stack and thereby resulting in a parasitic loss of power and energy. During standby, shunt current and its associated internal discharge reactions can generate heat and increase stack temperature, potentially leading to thermal precipitation in the positive half-cell. This study aims to investigate the effect of shunt current on stack efficiency and temperature variation during standby periods for a 40-cell stack. Dynamic models based on mass balance, energy balance and electrical circuit are developed for simulations and the results provide an insight into stack performance that will aid in optimising stack design and suitable cooling strategies for the VFB.

  17. Modular fuel-cell stack assembly

    DOEpatents

    Patel, Pinakin; Urko, Willam

    2008-01-29

    A modular multi-stack fuel-cell assembly in which the fuel-cell stacks are situated within a containment structure and in which a gas distributor is provided in the structure and distributes received fuel and oxidant gases to the stacks and receives exhausted fuel and oxidant gas from the stacks so as to realize a desired gas flow distribution and gas pressure differential through the stacks. The gas distributor is centrally and symmetrically arranged relative to the stacks so that it itself promotes realization of the desired gas flow distribution and pressure differential.

  18. Influence of electric fields on absorption spectra of AAB-stacked trilayer graphene

    NASA Astrophysics Data System (ADS)

    Chiu, Chih-Wei; Chen, Rong-Bin

    2016-06-01

    The tight-binding model and gradient approximation are, respectively, used to calculate the band structures and the absorption spectra of AAB-stacked trilayer graphene (AAB-TLG). AAB stacking, the lowest symmetric geometric structure in trilayer systems, induces the most atomic interactions, and thus, complicates the energy dispersions and the joint density of states. AAB stacking enriches the optical absorption spectra [A(ω)], which dictate the characteristics of the electronic structure. A(ω) are changed by the static electric field, such as the intensity, frequency, and number of absorption structures. These results contrast sharply with those for TLG in other stacking configurations.

  19. Nature and magnitude of aromatic base stacking in DNA and RNA: Quantum chemistry, molecular mechanics, and experiment.

    PubMed

    Sponer, Jiří; Sponer, Judit E; Mládek, Arnošt; Jurečka, Petr; Banáš, Pavel; Otyepka, Michal

    2013-12-01

    Base stacking is a major interaction shaping up and stabilizing nucleic acids. During the last decades, base stacking has been extensively studied by experimental and theoretical methods. Advanced quantum-chemical calculations clarified that base stacking is a common interaction, which in the first approximation can be described as combination of the three most basic contributions to molecular interactions, namely, electrostatic interaction, London dispersion attraction and short-range repulsion. There is not any specific π-π energy term associated with the delocalized π electrons of the aromatic rings that cannot be described by the mentioned contributions. The base stacking can be rather reasonably approximated by simple molecular simulation methods based on well-calibrated common force fields although the force fields do not include nonadditivity of stacking, anisotropy of dispersion interactions, and some other effects. However, description of stacking association in condensed phase and understanding of the stacking role in biomolecules remain a difficult problem, as the net base stacking forces always act in a complex and context-specific environment. Moreover, the stacking forces are balanced with many other energy contributions. Differences in definition of stacking in experimental and theoretical studies are explained. PMID:23784745

  20. Interrelation of Entropic Contributors to π -Stacking in Solution

    NASA Astrophysics Data System (ADS)

    Starodub, Maria A.; Lantushenko, Anastasia O.; Evstigneev, Vladislav P.; Golovchenko, Igor V.; Mykhina, Yulia V.; Savin, Valery V.; Evstigneev, Maxim P.

    2016-08-01

    The recently published most complete set of thermodynamical data on self- and hetero-complexation of aromatic molecules measured under comparable experimental conditions were analyzed. The main aim of this study is to get insights into contribution of various entropic factors to π -stacking in aqueous solution. It was found that the experimental entropy change on π -stacking is determined by counterbalancing effects of two principal factors, i.e., the hydrophobic interaction (positive contribution) and the loss of degrees of freedom (negative contribution) modulated by the electrostatic contribution. Other factors, including the mixing entropy contribution, were shown to be less important.

  1. Aggregated enhanced Raman scattering in Fe(III)PPIX solutions: the effects of concentration and chloroquine on excitonic interactions.

    PubMed

    Webster, Grant T; McNaughton, Don; Wood, Bayden R

    2009-05-14

    Resonance Raman spectra of hematin and hemin solutions are reported for 413 and 514 nm excitation wavelengths. Enhancement of A1g modes (1569 and 1370 cm(-1)) and B1g modes (1124 and 755 cm(-1)) as a function of increased concentration are observed when irradiating with 514 nm laser excitation but not 413 nm. This can be rationalized by considering an excitonic coupling mechanism. As the concentration of hematin increases there is an increased probability of supramolecular interactions between iron(III) protoporphyrin IX (Fe(III)PPIX) units occurring. The Fe(III)PPIX concentration reaches a saturation point in solution and excitonic coupling reaches a maximum causing the enhancement profile to plateau when applying 514 nm excitation. In contrast, when using 413 nm excitation there were no changes in band intensity with increased concentration showing that excitonic coupling through supramolecular interactions for aggregated solutions is wavelength dependent. Electronic absorption spectra show that as the concentration of Fe(III)PPIX increases in solution the Soret band is slightly blue shifted and the Q-band significantly broadens supporting the excitonic hypothesis. Understanding the mechanism that accounts for the Raman photophysical behavior of hemes at high concentrations provided an indirect method to monitor antimalarial drug interactions. A second aim was to investigate chloroquine binding to Fe(III)PPIX-OH/H2O monomers, pi-pi dimers and micro-oxo dimers formed in highly concentrated solutions approaching those of the digestive vacuole of the P. falciparum malaria parasite using excitonic Raman enhancement. It was hypothesized that the Raman excitonic enhancement mechanism could be impeded in heme aggregated solutions by the addition of chloroquine. This would result in a reduction in heme bands associated with the A1g modes including nu4. Resonance Raman spectra recorded using 514 nm excitation show that chloroquine (CQ) acts as a molecular spacer and binds

  2. Correlated lateral phase separations in stacks of lipid membranes

    NASA Astrophysics Data System (ADS)

    Hoshino, Takuma; Komura, Shigeyuki; Andelman, David

    2015-12-01

    Motivated by the experimental study of Tayebi et al. [Nat. Mater. 11, 1074 (2012)] on phase separation of stacked multi-component lipid bilayers, we propose a model composed of stacked two-dimensional Ising spins. We study both its static and dynamical features using Monte Carlo simulations with Kawasaki spin exchange dynamics that conserves the order parameter. We show that at thermodynamical equilibrium, due to strong inter-layer correlations, the system forms a continuous columnar structure for any finite interaction across adjacent layers. Furthermore, the phase separation shows a faster dynamics as the inter-layer interaction is increased. This temporal behavior is mainly due to an effective deeper temperature quench because of the larger value of the critical temperature, Tc, for larger inter-layer interaction. When the temperature ratio, T/Tc, is kept fixed, the temporal growth exponent does not increase and even slightly decreases as a function of the increased inter-layer interaction.

  3. Measurement of CP Parameters in B- --> D(pi+pi-pi0)K- and Study of the X(3872) in B --> J/psi pi+ pi- K with the BaBar Detector

    SciTech Connect

    Winklmeier, Frank; /SLAC

    2006-09-18

    This dissertation presents two analyses performed on data collected with the BABAR detector at the SLAC PEP-II e{sup +}e{sup -} asymmetric-energy B Factory. First, a Dalitz analysis is shown that performs the first measurement of CP violation parameters in the decay B{sup -} {yields} D{sub {pi}{sup +}{pi}{sup -}{pi}{sup 0}}K{sup -} using the decay rate asymmetry and D{sup 0} - {bar D}{sup 0} interference. The results can be used to further constrain the value of the CKM angle {gamma}. The second analysis studies the properties of the X(3872) in neutral and charged B {yields} J/{psi}{pi}{sup +}{pi}{sup -}K decays. Measurements of the branching ratio and mass are presented as well as the search for additional resonances at higher masses.

  4. Study of J/psi pi+ pi- States Produced in B0 to J/psi pi+ pi- K^0 and B- to J/psi pi+ pi- K-

    SciTech Connect

    Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; Grauges, E.; Palano, A.; Pappagallo, M.; Pompili, A.; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; Eigen, G.; Ofte, I.; Stugu, B. /Bergen U. /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /Pisa U. /INFN, Pisa /Prairie View A-M /Princeton U. /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Stony Brook /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Vanderbilt U. /Victoria U. /Warwick U. /Wisconsin U., Madison /Yale U.

    2005-07-27

    We present results of a search for the X(3872) in B{sup 0} {yields} X(3872)K{sub S}{sup 0}, X(3872) {yields} J/{psi}{pi}{sup +}{pi}{sup -}, improved measurements of B{sup -} {yields} X(3872)K{sup -}, and a study of the J/{psi}{pi}{sup +}{pi}{sup -} mass region above the X(3872). We use 232 million B{bar B} pairs collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II e{sup +}e{sup -} asymmetric-energy storage rings. The results include the 90% confidence interval 1.34 x 10{sup -6} < {Beta}(B{sup 0} {yields} X(3872)K{sup 0}, X {yields} J/{psi}{pi}{sup +}{pi}{sup -}) < 10.3 x 10{sup -6} and the branching fraction {Beta}(B{sup -} {yields} X(3872)K{sup -}, X {yields} J/{psi}{pi}{sup +}{pi}{sup -}) = (10.1 {+-} 2.5 {+-} 1.0) x 10{sup -6}. We observe a (2.7 {+-} 1.3 {+-} 0.2) MeV/c{sup 2} mass difference of the X(3872) produced in the two decay modes. Furthermore, we find an excess of J/{psi}{pi}{sup +}{pi}{sup -} events with an invariant mass just above 4.2 GeV/c{sup 2} that is consistent with recent observations in initial state radiation events.

  5. Study of the tau- ---> pi- pi- pi+ pi0 pi0 nu/tau and tau- --> 3h- 2h+ nu/tau Decays Using the BaBar Detector

    SciTech Connect

    Sobie, R.; /Victoria U.

    2005-06-21

    The {tau}{sup -} {yields} {pi}{sup -}{pi}{sup -}{pi}{sup +}{pi}{sup 0}{pi}{sup 0}{nu}{sub {tau}} and {tau}{sup -} {yields} 3h{sup -} 2h{sup +} {nu}{sub {tau}} decays have been studied using the BABAR experiment at the PEP-II e{sup +}e{sup -} storage ring. Preliminary branching fractions are given for the {tau}{sup -} {yields} {pi}{sup -}{pi}{sup -}{pi}{sup +}{pi}{sup 0}{pi}{sup 0}{nu}{sub {tau}} and to the sub-channels {tau}{sup -} {yields} {eta}{pi}{sup -} {pi}{sup 0}{nu}{sub {tau}} and {tau}{sup -} {yields} {omega}(782){pi}{sup -}{pi}{sup 0}{nu}{sub {tau}}. A preliminary upper limit is given on the branching fraction for the {phi}(1020){pi}{sup -}{pi}{sup 0}{nu}{sub {tau}} mode. In addition a preliminary measurement of the branching fraction of the {tau}{sup -} {yields} 3h{sup -}2h{sup +} {nu}{sub {tau}} decay (h = {pi}, K) is presented.

  6. On the role of the final-state interactions in rare B decays

    SciTech Connect

    Kaidalov, A. B.; Vysotsky, M. I.

    2009-12-15

    The effects of final-state interactions (FSI) in hadronic B decays are investigated. The model for FSI, based on Regge phenomenology of high-energy hadronic interactions, is proposed. It is shown that this model explains the pattern of phases in matrix elements of B {yields} {pi}{pi} and B {yields} {rho}{rho} decays. These phases play an important role for CP violation in B decays. The most precise determination of the unitarity triangle angle {alpha} from B{sub d} {yields} {rho}{pi} decays is performed. The relation between CP asymmetries in B {yields} K{pi} decays is discussed. It is emphasized that the large-distance FSI can explain the structure of polarizations of the vector mesons in B decays and other puzzles like a very large branching ratio of the B decay to {Xi}{sub c{Lambda}c}.

  7. Rhythmic ring–ring stacking drives the circadian oscillator clockwise

    PubMed Central

    Chang, Yong-Gang; Tseng, Roger; Kuo, Nai-Wei; LiWang, Andy

    2012-01-01

    The oscillator of the circadian clock of cyanobacteria is composed of three proteins, KaiA, KaiB, and KaiC, which together generate a self-sustained ∼24-h rhythm of phosphorylation of KaiC. The mechanism propelling this oscillator has remained elusive, however. We show that stacking interactions between the CI and CII rings of KaiC drive the transition from the phosphorylation-specific KaiC–KaiA interaction to the dephosphorylation-specific KaiC–KaiB interaction. We have identified the KaiB-binding site, which is on the CI domain. This site is hidden when CI domains are associated as a hexameric ring. However, stacking of the CI and CII rings exposes the KaiB-binding site. Because the clock output protein SasA also binds to CI and competes with KaiB for binding, ring stacking likely regulates clock output. We demonstrate that ADP can expose the KaiB-binding site in the absence of ring stacking, providing an explanation for how it can reset the clock. PMID:22967510

  8. 49 CFR 178.980 - Stacking test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... the qualification of all Large Packagings design types intended to be stacked. (b) Special preparation for the stacking test. (1) All Large Packagings except flexible Large Packaging design types must be... permissible gross mass and stacked on the test Large Packaging; (ii) The calculated superimposed test...

  9. 49 CFR 178.606 - Stacking test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Stacking test. 178.606 Section 178.606... Packagings and Packages § 178.606 Stacking test. (a) General. All packaging design types other than bags must be subjected to a stacking test. (b) Number of test samples. Three test samples are required for...

  10. 49 CFR 178.980 - Stacking test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Stacking test. 178.980 Section 178.980... Packagings § 178.980 Stacking test. (a) General. The stacking test must be conducted for the qualification of... test. (1) All Large Packagings except flexible Large Packaging design types must be loaded to...

  11. 49 CFR 178.980 - Stacking test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Stacking test. 178.980 Section 178.980... Packagings § 178.980 Stacking test. (a) General. The stacking test must be conducted for the qualification of... test. (1) All Large Packagings except flexible Large Packaging design types must be loaded to...

  12. 49 CFR 178.606 - Stacking test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Stacking test. 178.606 Section 178.606... Packagings and Packages § 178.606 Stacking test. (a) General. All packaging design types other than bags must be subjected to a stacking test. (b) Number of test samples. Three test samples are required for...

  13. Glass transition dynamics of stacked thin polymer films

    NASA Astrophysics Data System (ADS)

    Fukao, Koji; Terasawa, Takehide; Oda, Yuto; Nakamura, Kenji; Tahara, Daisuke

    2011-10-01

    The glass transition dynamics of stacked thin films of polystyrene and poly(2-chlorostyrene) were investigated using differential scanning calorimetry and dielectric relaxation spectroscopy. The glass transition temperature Tg of as-stacked thin polystyrene films has a strong depression from that of the bulk samples. However, after annealing at high temperatures above Tg, the stacked thin films exhibit glass transition at a temperature almost equal to the Tg of the bulk system. The α-process dynamics of stacked thin films of poly(2-chlorostyrene) show a time evolution from single-thin-film-like dynamics to bulk-like dynamics during the isothermal annealing process. The relaxation rate of the α process becomes smaller with increase in the annealing time. The time scale for the evolution of the α dynamics during the annealing process is very long compared with that for the reptation dynamics. At the same time, the temperature dependence of the relaxation time for the α process changes from Arrhenius-like to Vogel-Fulcher-Tammann dependence with increase of the annealing time. The fragility index increases and the distribution of the α-relaxation times becomes smaller with increase in the annealing time for isothermal annealing. The observed change in the α process is discussed with respect to the interfacial interaction between the thin layers of stacked thin polymer films.

  14. PRECISION COSMOGRAPHY WITH STACKED VOIDS

    SciTech Connect

    Lavaux, Guilhem; Wandelt, Benjamin D.

    2012-08-01

    We present a purely geometrical method for probing the expansion history of the universe from the observation of the shape of stacked voids in spectroscopic redshift surveys. Our method is an Alcock-Paczynski (AP) test based on the average sphericity of voids posited on the local isotropy of the universe. It works by comparing the temporal extent of cosmic voids along the line of sight with their angular, spatial extent. We describe the algorithm that we use to detect and stack voids in redshift shells on the light cone and test it on mock light cones produced from N-body simulations. We establish a robust statistical model for estimating the average stretching of voids in redshift space and quantify the contamination by peculiar velocities. Finally, assuming that the void statistics that we derive from N-body simulations is preserved when considering galaxy surveys, we assess the capability of this approach to constrain dark energy parameters. We report this assessment in terms of the figure of merit (FoM) of the dark energy task force and in particular of the proposed Euclid mission which is particularly suited for this technique since it is a spectroscopic survey. The FoM due to stacked voids from the Euclid wide survey may double that of all other dark energy probes derived from Euclid data alone (combined with Planck priors). In particular, voids seem to outperform baryon acoustic oscillations by an order of magnitude. This result is consistent with simple estimates based on mode counting. The AP test based on stacked voids may be a significant addition to the portfolio of major dark energy probes and its potentialities must be studied in detail.

  15. Stack Monitor Operating Experience Review

    SciTech Connect

    L. C. Cadwallader; S. A. Bruyere

    2009-05-01

    Stack monitors are used to sense radioactive particulates and gases in effluent air being vented from rooms of nuclear facilities. These monitors record the levels and types of effluents to the environment. This paper presents the results of a stack monitor operating experience review of the U.S. Department of Energy (DOE) Occurrence Reporting and Processing System (ORPS) database records from the past 18 years. Regulations regarding these monitors are briefly described. Operating experiences reported by the U.S. DOE and in engineering literature sources were reviewed to determine the strengths and weaknesses of these monitors. Electrical faults, radiation instrumentation faults, and human errors are the three leading causes of failures. A representative “all modes” failure rate is 1E-04/hr. Repair time estimates vary from an average repair time of 17.5 hours (with spare parts on hand) to 160 hours (without spare parts on hand). These data should support the use of stack monitors in any nuclear facility, including the National Ignition Facility and the international ITER project.

  16. Stacks

    ERIC Educational Resources Information Center

    Kimber, Lizzie

    2010-01-01

    Linton Waters and Jayne Kranat ran a session on the Nuffield "Applying Mathematical Processes" (AMP) activities at BCME7 in Manchester in April this year. These 1-2 hour activities are revamps of some of the Graded Assessment in Mathematics (GAIM) resources, developed in the 1980s, and are freely available via the Nuffield website and the original…

  17. Stacking the odds for Golgi cisternal maturation

    PubMed Central

    Mani, Somya; Thattai, Mukund

    2016-01-01

    What is the minimal set of cell-biological ingredients needed to generate a Golgi apparatus? The compositions of eukaryotic organelles arise through a process of molecular exchange via vesicle traffic. Here we statistically sample tens of thousands of homeostatic vesicle traffic networks generated by realistic molecular rules governing vesicle budding and fusion. Remarkably, the plurality of these networks contain chains of compartments that undergo creation, compositional maturation, and dissipation, coupled by molecular recycling along retrograde vesicles. This motif precisely matches the cisternal maturation model of the Golgi, which was developed to explain many observed aspects of the eukaryotic secretory pathway. In our analysis cisternal maturation is a robust consequence of vesicle traffic homeostasis, independent of the underlying details of molecular interactions or spatial stacking. This architecture may have been exapted rather than selected for its role in the secretion of large cargo. DOI: http://dx.doi.org/10.7554/eLife.16231.001 PMID:27542195

  18. Stacking the odds for Golgi cisternal maturation.

    PubMed

    Mani, Somya; Thattai, Mukund

    2016-01-01

    What is the minimal set of cell-biological ingredients needed to generate a Golgi apparatus? The compositions of eukaryotic organelles arise through a process of molecular exchange via vesicle traffic. Here we statistically sample tens of thousands of homeostatic vesicle traffic networks generated by realistic molecular rules governing vesicle budding and fusion. Remarkably, the plurality of these networks contain chains of compartments that undergo creation, compositional maturation, and dissipation, coupled by molecular recycling along retrograde vesicles. This motif precisely matches the cisternal maturation model of the Golgi, which was developed to explain many observed aspects of the eukaryotic secretory pathway. In our analysis cisternal maturation is a robust consequence of vesicle traffic homeostasis, independent of the underlying details of molecular interactions or spatial stacking. This architecture may have been exapted rather than selected for its role in the secretion of large cargo. PMID:27542195

  19. Lightweight Stacks of Direct Methanol Fuel Cells

    NASA Technical Reports Server (NTRS)

    Narayanan, Sekharipuram; Valdez, Thomas

    2004-01-01

    An improved design concept for direct methanol fuel cells makes it possible to construct fuel-cell stacks that can weigh as little as one-third as much as do conventional bipolar fuel-cell stacks of equal power. The structural-support components of the improved cells and stacks can be made of relatively inexpensive plastics. Moreover, in comparison with conventional bipolar fuel-cell stacks, the improved fuel-cell stacks can be assembled, disassembled, and diagnosed for malfunctions more easily. These improvements are expected to bring portable direct methanol fuel cells and stacks closer to commercialization. In a conventional bipolar fuel-cell stack, the cells are interspersed with bipolar plates (also called biplates), which are structural components that serve to interconnect the cells and distribute the reactants (methanol and air). The cells and biplates are sandwiched between metal end plates. Usually, the stack is held together under pressure by tie rods that clamp the end plates. The bipolar stack configuration offers the advantage of very low internal electrical resistance. However, when the power output of a stack is only a few watts, the very low internal resistance of a bipolar stack is not absolutely necessary for keeping the internal power loss acceptably low.

  20. Nonlinear acoustic impedance of thermoacoustic stack

    NASA Astrophysics Data System (ADS)

    Ge, Huan; Fan, Li; Xiao, Shu-yu; Tao, Sha; Qiu, Mei-chen; Zhang, Shu-yi; Zhang, Hui

    2012-09-01

    In order to optimize the performances of the thermoacoustic refrigerator working with the high sound pressure level, the nonlinear acoustic characteristics of the thermoacoustic stack in the resonant pipe are studied. The acoustic fluid impedance of the stack made of copper mesh and set up in a resonant pipe is measured in the acoustic fields with different intensities. It is found that when the sound pressure level in the pipe increases to a critical value, the resistance of the stack increases nonlinearly with the sound pressure, while the reactance of the stack keeps constant. Based on the experimental results, a theory model is set up to describe the acoustic characteristics of the stack, according to the rigid frame theory and Forchheimmer equation. Furthermore, the influences of the sound pressure level, operating frequency, volume porosity, and length of the stack on the nonlinear impedance of the stack are evaluated.

  1. Two-body problem of core-region coupled magnetic vortex stacks

    NASA Astrophysics Data System (ADS)

    Hänze, Max; Adolff, Christian F.; Velten, Sven; Weigand, Markus; Meier, Guido

    2016-02-01

    The dynamics of all four combinations of possible polarity and circularity states in a stack of two vortices is investigated by time-resolved scanning transmission x-ray microscopy. The vortex stacks are excited by unidirectional magnetic fields leading to a collective oscillation. Four different modes are observed that depend on the relative polarizations and circularities of the stacks. They are excited to a driven oscillation. We observe a repulsive and attractive interaction of the vortex cores depending on their relative polarizations. The nonlinearity of this core interaction results in different trajectories that describe a two-body problem.

  2. First observation and measurement of the resonant structure of the lambda_b->lambda_c pi-pi+pi- decay mode

    SciTech Connect

    Azzurri, P.; Barria, P.; Ciocci, M.A.; Donati, S.; Vataga, E.

    2009-12-01

    The authors present the first observation of the {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} decay using data from an integrated luminosity of approximately 2.4 fb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV, collected with the CDF II detector at the Fermilab Tevatron. They also present the first observation of the resonant decays {Lambda}{sub b}{sup 0} {yields} {Sigma}{sub c}(2455){sup 0} {pi}{sup +}{pi}{sup -} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -}, {Lambda}{sub b}{sup 0} {yields} {Sigma}{sub c}(2455){sup ++}{pi}{sup -}{pi}{sup -} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -}, {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}(2595){sup +}{pi}{sup -} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} and {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}(2625){sup +}{pi}{sup -} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -}, and measure their relative branching ratios.

  3. First Observation of the Cabibbo-suppressed Decays Xi+(c) ---> Sigma+ pi- pi+ and Xi+(c) ---> Sigma- pi+ pi+ and Measurement of their Branching Ratios

    SciTech Connect

    Vazquez-Jauregui, E.; Engelfried, J.; Akgun, U.; Alkhazov, Georgiy; Amaro-Reyes, J.; Atamantchouk, A.G.; Ayan, Ahmet Sedat; Balatz, M.Y.; Blanco-Covarrubias, A.; Bondar, N.F.; Cooper, Peter S.; /Fermilab /Michigan U., Flint

    2008-04-01

    The authors report the first observation of two Cabibbo-suppressed decay modes, {Xi}{sub c}{sup +} {yields} {Sigma}{sup +}{pi}{sup -}{pi}{sup +} and {Xi}{sub c}{sup +} {yields} {Sigma}{sup -} {pi}{sup +}{pi}{sup +}. They observe 56 {+-} 13 over a background of 21, and 23 {+-} 7 over a background of 12 events, respectively, for the signals. The data were accumulated using the SELEX spectrometer during the 1996-1997 fixed target run at Fermilab, chiefly from a 600 GeV/c {Sigma}{sup -} beam. The branching ratios of the decays relative to the Cabibbo-favored {Xi}{sub c}{sup +} {yields} {Xi}{sup -}{pi}{sup +}{pi}{sup +} are measured to be B({Xi}{sub c}{sup +} {yields} {Sigma}{sup +}{pi}{sup -}{pi}{sup +})/B({xi}{sub c}{sup +} {yields} {Xi}{sup -} {pi}{sup +}{pi}{sup +}) = 0.50 {+-} 0.20, and B({Xi}{sub c}{sup +} {yields} {Sigma}{sup -}{pi}{sup +}{pi}{sup +})/B({Xi}{sub c}{sup +} {yields} {Xi}{sup -}{pi}{sup +}{pi}{sup +}) = 0.23 {+-} 0.11, respectively. They also report branching ratios for the same decay modes of the {Lambda}{sub c}{sup +} relative to {Lambda}{sub c}{sup +} {yields} pK{sup -}{pi}{sup +}.

  4. Exotic and qq-bar resonances in the pi+pi-pi- system produced in pi-p collisions at 18 GeV/c

    SciTech Connect

    S. U. Chung; K. Danyo; R. W. Hackenburg; C. Olchanski; J. S. Suh; H. J. Willutzki; S. P. Denisov; V. Dorofeev; V. V. Lipaev; A. V. Popov; D. I. Ryabchikov; Z. Bar-Yam; J. P. Dowd; P. Eugenio; M. Hayek; W. Kern; E. King; N. Shenhav; V. A. Bodyagin; O. L. Kodolova; V. L. Korotkikh; M. A. Kostin; A. I. Ostrovidov; L. I. Sarycheva; I. N. Vardanyan; A. A. Yershov; D. S. Brown; X. L. Fan; D. Joffe; T. K. Pedlar; K. K. Seth; A. Tomaradze; T. Adams; J. M. Bishop; N. M. Cason; E. I. Ivanov; J. M. LoSecco; J. J. Manak; W. D. Shephard; D. L. Stienike; S. A. Taegar; G. S. Adams; J. P. Cummings; J. Hu; J. Kuhn; M. Lu; J. Napolitano; D. B. White; M. Witkowski; M. Nozar; X. Shen; D. P. Weygand

    2002-03-01

    A partial-wave analysis of the reaction pi{sup -}p-->pi{sup +}pi{sup -}pi{sup -}p at 18 GeV/c has been performed on a data sample of 250 000 events obtained in the Brookhaven experiment E852. The well-known a{sub 1}(1260), a{sub 2}(1320) and pi{sub 2}(1670) resonant states are observed. The existence of the pi(1800), a{sub 1}(1700) and a{sub 4}(2040) states is confirmed. The a{sub 3}(1874) state is also observed. The exotic 1{sup -+} pi{sub 1}(1600) state produced in the natural parity exchange process is found to decay in the rho(770)pi{sup -} channel. A mass-dependent fit results in a resonance mass of 1593{+-}8{sub -47}{sup +29} MeV/c{sup 2} and a width of 168{+-}20{sub -12}{sup +150} MeV/c{sup 2}.

  5. Measurement of the branching fraction ${\\mathcal{B}}(\\Lambda^0_b\\rightarrow \\Lambda^+_c\\pi^-\\pi^+\\pi^-)$ at CDF

    SciTech Connect

    Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J.A.; Arisawa, T.; Artikov, A.; /Dubna, JINR /Texas A-M

    2011-12-01

    We report an analysis of the {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} decay in a data sample collected by the CDF II detector at the Fermilab Tevatron corresponding to 2.4 fb{sup -1} of integrated luminosity. We reconstruct the currently largest samples of the decay modes {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}(2595){sup +}{pi}{sup -} (with {Lambda}{sub c}(2595){sup +} {yields} {Lambda}{sub c}{sup +}{pi}{sup +}{pi}{sup -}), {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}(2625){sup +}{pi}{sup -} (with {Lambda}{sub c}(2625){sup +} {yields} {Lambda}{sub c}{sup +}{pi}{sup +}{pi}{sup -}), {Lambda}{sub b}{sup 0} {yields} {Sigma}{sub c}(2455){sup ++}{pi}{sup -}{pi}{sup -} (with {Sigma}{sub c}(2455){sup ++} {yields} {Lambda}{sub c}{sup +}{pi}{sup +}), and {Lambda}{sub b}{sup 0} {yields} {Sigma}{sub c}(2455)0{pi}{sup +}{pi}{sup -} (with {Sigma}{sub c}(2455)0 {yields} {Lambda}{sub c}{sup +}{pi}{sup -}) and measure the branching fractions relative to the {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -} branching fraction. We measure the ratio {Beta}({Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -})/ {Beta}({Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -})=3.04 {+-} 0.33(stat){sub -0.55}{sup +0.70}(syst) which is used to derive {Beta}({Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -})=(26.8{sub -11.2}{sup +11.9}) x 10{sup -3}.

  6. Study of the doubly and singly Cabibbo suppressed decays D+ --> K+ pi- pi+ and D(s)+ --> K+ pi- pi+ in the FOCUS experiment

    SciTech Connect

    Edera, Laura

    2005-01-01

    This thesis illustrates a complete study of the doubly and singly Cabibbo suppressed decays D{sup +} and D{sub s}{sup +} {yields} K{sup +} {pi}{sup -}{pi}{sup +}. Data for this analysis have been collected by the fixed-target high-energy photoproduction experiment FOCUS at Fermilab. The authors have selected the D{sup +} and D{sub s}{sup +} samples with cuts to obtain a sufficiently high statistics, a good signal to noise ratio and, at the same time, eliminate possible contaminations from the more copious and favored decays. The D{sup +} yield consists of 189 {+-} 24 events, with a signal to noise ratio {approx} 1; the D{sub s}{sup +} yield is 567 {+-} 31 and the signal to noise ratio is {approx} 2.5. The authors have measured {Lambda}(D{sup +} {yields} K{sup +}{pi}{sup -}{pi}{sup +})/{Lambda}(D{sup +} {yields} K{sup -}{pi}{sup +}{pi}{sup +}) = 0.0065 {+-} 0.0008 {+-} 0.004 and {Lambda}(D{sub s}{sup +} {yields} K{sup +}{pi}{sup -}{pi}{sup +})/{Lambda}(D{sub s}{sup +} {yields} K{sup +}K{sup -}{pi}{sup +}) = 0.127 {+-} 0.007 {+-} 0.014, improving the previous determinations of a factor of 2 and 5, respectively. The author has also performed a Dalitz plot analysis for both decays. The amplitude analysis for D{sub s}{sup +} {yields} K{sup +}{pi}{sup -}{pi}{sup +} represents the first available measurement for this channel.

  7. Measurement of the Inclusive Branching FractionsB(B^- to D^+ Pi^- Pi^-) and B(B^- to D*^+ Pi^- Pi^-)

    SciTech Connect

    Eschenburg, Vance Onno

    2007-07-17

    The D{sub J}{sup 0} is a family of four orbitally excited mesons: D*{sub 2}(2460){sup 0}, D{sub 1}(2420){sup 0}, D{sub 1}(j = 1/2){sup -}, and D*{sub 0}(j = 1/2){sup 0}. This dissertation presents the measurements of the inclusive branching fractions, {Beta}(B{sup -} {yields} D*{sup +}{pi}{sup -}{pi}{sup -}) and {Beta}(B{sup -} {yields} D{sup +}{pi}{sup -}{pi}{sup -}). The D{sub J}{sup 0} provides an intermediate resonance for those two modes. The data used for this analysis consists of Runs 1-5 with total integrated luminosity of 343.38 fb{sup -1}, which is corresponding to 383.92 million B{bar B} pairs, provided by the BABAR detector at the PEP-II asymmetric B Factory. The values presented are: {Beta}(B{sup -} {yields} D{sup +}{pi}{sup -}{pi}{sup -}) = (1.12 {+-} 0.02 {+-} 0.08) x 10{sup -3}; {Beta}(B{sup -} {yields} D*{sup +}{pi}{sup -}{pi}{sup -}) = (1.67 {+-} 0.03 {+-} 0.13) x 10{sup -3}.

  8. Branching Ratio Measurements of B ---> J/psi eta K and B+- ---> D0 K+- with D0 ---> pi+ pi- pi0

    SciTech Connect

    Zeng, Qinglin; /Colorado State U.

    2006-03-08

    Results are presented for the decays of B {yields} J/{psi}{eta}K and B{sup {+-}} {yields} DK{sup {+-}}, respectively, with experimental data collected with BABAR detector at PEP-II, located at Stanford Linear Accelerator Center (SLAC). With 90 x 10{sup 6} B{bar B} events at the {Upsilon}(4S) resonance, we obtained branching fractions of {Beta}(B{sup {+-}} {yields} J/{psi}{eta}K{sup {+-}}) = [10.8 {+-} 2.3(stat) {+-} 2.4(syst)] x 10{sup -5} and {Beta}(B{sup 0} {yields} J/{psi}{eta}K{sub S}{sup 0}) = [8.4 {+-} 2.6(stat) {+-} 2.7(syst)] x 10{sup -5}; and we set an upper limit of {Beta}[B{sup {+-}} {yields} X(3872)K{sup {+-}} {yields} J/{psi}{eta}K{sup {+-}}] < 7.7 x 10{sup -6} at 90% confidence level. The branching fraction of decay chain {Beta}(B{sup {+-}} {yields} DK{sup {+-}} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0}K{sup {+-}}) = [5.5 {+-} 1.0(stat) {+-} 0.7(syst)] x 10{sup -6} with 229 x 10{sup 6} B{bar B} events at {Upsilon}(4S) resonance, here D represents the neutral D meson. The decay rate asymmetry is A = 0.02 {+-} 0.16(stat) {+-} 0.03(syst) for this full decay chain. This decay can be used to extract the unitarity angle {gamma}, a weak CP violation phase, through the interference of decay production of D{sup 0} and {bar D}{sup 0} to {pi}{sup +}{pi}{sup -}{pi}{sup 0}.

  9. A High Volume Stack Sampler

    NASA Technical Reports Server (NTRS)

    Boubel, Richard W.

    1971-01-01

    The stack sampler described in this paper has been developed to overcome the difficulties of particulate sampling with presently available equipment. Its use on emissions from hog fuel fired boilers, back-fired incinerators, wigwam burners, asphalt plants, and seed cleaning cyclones is reported. The results indicate that the sampler is rapid and reliable in its use. It is relatively simple and inexpensive to operate. For most sources it should be considered over the more complicated and expensive sampling trains being used and specified.

  10. Status of MCFC stack development at Hitachi

    SciTech Connect

    Takashima, S.; Kahara, T.; Takeuchi, M.

    1996-12-31

    Hitachi, Ltd. has been developing Molten Carbonate Fuel Cells in the New Sunshine project in Japan, and Hitachi is taking part in the development of 1,000kW MCFC pilot plant at Kawagoe. Hitachi is engaged in system planning of the 1,000kW pilot plant, design and manufacturing of the reformer subsystem and the fuel cell subsystem, and design and manufacturing of the 250kW stacks for the 1,000kW plant. The 250kW stacks are developed on the basis of the results of the 100kW stack in 1993 and the following 25kW stack in 1994. In parallel to the stack development, Hitachi is also conducting researches for long endurance cells and stacks. In addition to the researches for anode, cathode, electrolyte, and electrolyte matrix, improvement of temperature distribution in stacks is investigated to extend the stack life. This paper describes the planning status of the 250kW stacks for the 1,000kW MCFC plant and the developing status of stack cooling method for longer life.

  11. Modeling theta-theta Interactions with the Effective Fragment Potential Method: The Benzene Dimer and Substituents

    SciTech Connect

    Toni Smithl; Lyudmila V. Slipchenko; Mark S. Gordon

    2008-02-27

    This study compares the results of the general effective fragment potential (EFP2) method to the results of a previous combined coupled cluster with single, double, and perturbative triple excitations [CCSD(T)] and symmetry-adapted perturbation theory (SAPT) study [Sinnokrot and Sherrill, J. Am. Chem. Soc., 2004, 126, 7690] on substituent effects in {pi}-{pi} interactions. EFP2 is found to accurately model the binding energies of the benzene-benzene, benzene-phenol, benzene-toluene, benzene-fluorobenzene, and benzene-benzonitrile dimers, as compared with high-level methods [Sinnokrot and Sherrill, J. Am. Chem. Soc., 2004, 126, 7690], but at a fraction of the computational cost of CCSD(T). In addition, an EFP-based Monte Carlo/simulated annealing study was undertaken to examine the potential energy surface of the substituted dimers.

  12. Free energy analysis and mechanism of base pair stacking in nicked DNA.

    PubMed

    Häse, Florian; Zacharias, Martin

    2016-09-01

    The equilibrium of stacked and unstacked base pairs is of central importance for all nucleic acid structure formation processes. The stacking equilibrium is influenced by intramolecular interactions between nucleosides but also by interactions with the solvent. Realistic simulations on nucleic acid structure formation and flexibility require an accurate description of the stacking geometry and stability and its sequence dependence. Free energy simulations have been conducted on a series of double stranded DNA molecules with a central strand break (nick) in one strand. The change in free energy upon unstacking was calculated for all ten possible base pair steps using umbrella sampling along a center-of-mass separation coordinate and including a comparison of different water models. Comparison to experimental studies indicates qualitative agreement of the stability order but a general overestimation of base pair stacking interactions in the simulations. A significant dependence of calculated nucleobase stacking free energies on the employed water model was observed with the tendency of stacking free energies being more accurately reproduced by more complex water models. The simulation studies also suggest a mechanism of stacking/unstacking that involves significant motions perpendicular to the reaction coordinate and indicate that the equilibrium nicked base pair step may slightly differ from regular B-DNA geometry in a sequence-dependent manner. PMID:27407106

  13. Stacking-Dependent Interlayer Coupling in Trilayer MoS₂ with Broken Inversion Symmetry.

    PubMed

    Yan, Jiaxu; Xia, Juan; Wang, Xingli; Liu, Lei; Kuo, Jer-Lai; Tay, Beng Kang; Chen, Shoushun; Zhou, Wu; Liu, Zheng; Shen, Ze Xiang

    2015-12-01

    The stacking configuration in few-layer two-dimensional (2D) materials results in different structural symmetries and layer-to-layer interactions, and hence it provides a very useful parameter for tuning their electronic properties. For example, ABA-stacking trilayer graphene remains semimetallic similar to that of monolayer, while ABC-stacking is predicted to be a tunable band gap semiconductor under an external electric field. Such stacking dependence resulting from many-body interactions has recently been the focus of intense research activities. Here we demonstrate that few-layer MoS2 samples grown by chemical vapor deposition with different stacking configurations (AA, AB for bilayer; AAB, ABB, ABA, AAA for trilayer) exhibit distinct coupling phenomena in both photoluminescence and Raman spectra. By means of ultralow-frequency (ULF) Raman spectroscopy, we demonstrate that the evolution of interlayer interaction with various stacking configurations correlates strongly with layer-breathing mode (LBM) vibrations. Our ab initio calculations reveal that the layer-dependent properties arise from both the spin-orbit coupling (SOC) and interlayer coupling in different structural symmetries. Such detailed understanding provides useful guidance for future spintronics fabrication using various stacked few-layer MoS2 blocks. PMID:26565932

  14. Free energy analysis and mechanism of base pair stacking in nicked DNA

    PubMed Central

    Häse, Florian; Zacharias, Martin

    2016-01-01

    The equilibrium of stacked and unstacked base pairs is of central importance for all nucleic acid structure formation processes. The stacking equilibrium is influenced by intramolecular interactions between nucleosides but also by interactions with the solvent. Realistic simulations on nucleic acid structure formation and flexibility require an accurate description of the stacking geometry and stability and its sequence dependence. Free energy simulations have been conducted on a series of double stranded DNA molecules with a central strand break (nick) in one strand. The change in free energy upon unstacking was calculated for all ten possible base pair steps using umbrella sampling along a center-of-mass separation coordinate and including a comparison of different water models. Comparison to experimental studies indicates qualitative agreement of the stability order but a general overestimation of base pair stacking interactions in the simulations. A significant dependence of calculated nucleobase stacking free energies on the employed water model was observed with the tendency of stacking free energies being more accurately reproduced by more complex water models. The simulation studies also suggest a mechanism of stacking/unstacking that involves significant motions perpendicular to the reaction coordinate and indicate that the equilibrium nicked base pair step may slightly differ from regular B-DNA geometry in a sequence-dependent manner. PMID:27407106

  15. Ultra-dark graphene stack metamaterials

    NASA Astrophysics Data System (ADS)

    Chugh, Sunny; Man, Mengren; Chen, Zhihong; Webb, Kevin J.

    2015-02-01

    We present a fabrication method to achieve a graphene stack metamaterial, a periodic array of unit cells composed of graphene and a thin insulating spacer, that allows accumulation of the strong absorption from individual graphene sheets and low reflectivity from the stack. The complex sheet conductivity of graphene from experimental data models the measured power transmitted as a function of wavelength and number of periods in the stack. Simulated results based on the extracted graphene complex sheet conductivity for thicker stacks suggest that the graphene stack reflectivity and the per-unit-length absorption can be controlled to exceed the performance of competing light absorbers. Furthermore, the electrical properties of graphene coupled with the stack absorption characteristics provide for applications in optoelectronic devices.

  16. Photogrammetric Technique for Timber Stack Volume Contol

    NASA Astrophysics Data System (ADS)

    Knyaz, V. A.; Maksimov, A. A.

    2014-08-01

    The problem of accurate log volume measurement is a very important, especially in case of seaport volume control where logs are put in a huge stack of hundred meters length and a time for volume control is strongly restricted. Current technology of volume control use manual means such as measuring tape, so the process of measurement is rather inaccurate and time consuming. To estimate the volume of timber stack its frontal area is measured and some control parts of a stack are used for stacking coefficient (wood density in a stack) determination. Non-contact vision based technique is proposed for manual measurements substituting. The developed methods are implemented in portable photogrammetric system for stack parameters measuring and documenting.

  17. Prediction of temperature profile in MCFC stack

    SciTech Connect

    Lee, Kab Soo; Kim, Hwayong; Hong, Seong-An; Lim, Hee Chun

    1996-12-31

    A simple three dimensional model was developed to simulate the temperature distribution and the performance of various flow types of the MCFC stack. The objective of this study was to understand the complicated phenomena occurring in the MCFC stack and to supply the basic data for optimizing the operating condition of the MCFC stack. Assuming that the stack consists of a number of differential elements which have uniform temperature and gas composition, the model was solved by finite difference method. The performance of this model was demonstrated by comparing the calculated value with experimental data of the 1.5kW class co-flow type MCFC stack operated in KIST. This model can be utilized as a simple diagnostic tool in case of the operational abnormality such as the hot spot which often occurs inside the stack.

  18. Giant permanent dipole moment of two-dimensional excitons bound to a single stacking fault

    NASA Astrophysics Data System (ADS)

    Karin, Todd; Linpeng, Xiayu; Glazov, M. M.; Durnev, M. V.; Ivchenko, E. L.; Harvey, Sarah; Rai, Ashish K.; Ludwig, Arne; Wieck, Andreas D.; Fu, Kai-Mei C.

    2016-07-01

    We investigate the magneto-optical properties of excitons bound to single stacking faults in high-purity GaAs. We find that the two-dimensional stacking fault potential binds an exciton composed of an electron and a heavy hole, and we confirm a vanishing in-plane hole g -factor, consistent with the atomic-scale symmetry of the system. The unprecedented homogeneity of the stacking-fault potential leads to ultranarrow photoluminescence emission lines (with a full width at half-maximum ≲80 μ eV ) and reveals a large magnetic nonreciprocity effect that originates from the magneto-Stark effect for mobile excitons. These measurements unambiguously determine the direction and magnitude of the giant electric dipole moment (≳e ×10 nm ) of the stacking-fault exciton, making stacking faults a promising new platform to study interacting excitonic gases.

  19. Fast exciton diffusion in chiral stacks of conjugated p-phenylene vinylene oligomers

    NASA Astrophysics Data System (ADS)

    Herz, L. M.; Daniel, C.; Silva, C.; Hoeben, F. J.; Schenning, A. P.; Meijer, E. W.; Friend, R. H.; Phillips, R. T.

    2003-07-01

    The ultrafast dynamics of photoexcitations have been studied in chiral stacks of conjugated p-phenylene vinylene molecules functionalized with hydrogen-bonding groups. The results indicate that in solution, π-π interactions between the molecules give rise to fast exciton diffusion along the stacking axis of the assemblies. The chiral nature of the assemblies is found to cause a rotation of the dipole moment of excitons propagating along the stacks as indicated by time-resolved measurements of the photoluminescence polarization anisotropy. The observed exciton diffusion and energy relaxation dynamics in the molecular stacks are shown to be very similar to those found in conjugated polymer films. Moreover, it is demonstrated that through changes in the temperature of the surrounding solvent, the stacks can be dissociated reversibly as shown by a marked reduction in the diffusivity of excitons.

  20. Hydrogen Embrittlement And Stacking-Fault Energies

    NASA Technical Reports Server (NTRS)

    Parr, R. A.; Johnson, M. H.; Davis, J. H.; Oh, T. K.

    1988-01-01

    Embrittlement in Ni/Cu alloys appears related to stacking-fault porbabilities. Report describes attempt to show a correlation between stacking-fault energy of different Ni/Cu alloys and susceptibility to hydrogen embrittlement. Correlation could lead to more fundamental understanding and method of predicting susceptibility of given Ni/Cu alloy form stacking-fault energies calculated from X-ray diffraction measurements.

  1. Flexible interconnects for fuel cell stacks

    DOEpatents

    Lenz, David J.; Chung, Brandon W.; Pham, Ai Quoc

    2004-11-09

    An interconnect that facilitates electrical connection and mechanical support with minimal mechanical stress for fuel cell stacks. The interconnects are flexible and provide mechanically robust fuel cell stacks with higher stack performance at lower cost. The flexible interconnects replace the prior rigid rib interconnects with flexible "fingers" or contact pads which will accommodate the imperfect flatness of the ceramic fuel cells. Also, the mechanical stress of stacked fuel cells will be smaller due to the flexibility of the fingers. The interconnects can be one-sided or double-sided.

  2. Film stacking architecture for immersion lithography process

    NASA Astrophysics Data System (ADS)

    Goto, Tomohiro; Sanada, Masakazu; Miyagi, Tadashi; Shigemori, Kazuhito; Kanaoka, Masashi; Yasuda, Shuichi; Tamada, Osamu; Asai, Masaya

    2008-03-01

    In immersion lithography process, film stacking architecture will be necessary due to film peeling. However, the architecture will restrict lithographic area within a wafer due to top side EBR accuracy In this paper, we report an effective film stacking architecture that also allows maximum lithographic area. This study used a new bevel rinse system on RF3 for all materials to make suitable film stacking on the top side bevel. This evaluation showed that the new bevel rinse system allows the maximum lithographic area and a clean wafer edge. Patterning defects were improved with suitable film stacking.

  3. Stacking in RNA: NMR of Four Tetramers Benchmark Molecular Dynamics

    PubMed Central

    2015-01-01

    Molecular dynamics (MD) simulations for RNA tetramers r(AAAA), r(CAAU), r(GACC), and r(UUUU) are benchmarked against 1H–1H NOESY distances and 3J scalar couplings to test effects of RNA torsion parametrizations. Four different starting structures were used for r(AAAA), r(CAAU), and r(GACC), while five starting structures were used for r(UUUU). On the basis of X-ray structures, criteria are reported for quantifying stacking. The force fields, AMBER ff99, parmbsc0, parm99χ_Yil, ff10, and parmTor, all predict experimentally unobserved stacks and intercalations, e.g., base 1 stacked between bases 3 and 4, and incorrect χ, ϵ, and sugar pucker populations. The intercalated structures are particularly stable, often lasting several microseconds. Parmbsc0, parm99χ_Yil, and ff10 give similar agreement with NMR, but the best agreement is only 46%. Experimentally unobserved intercalations typically are associated with reduced solvent accessible surface area along with amino and hydroxyl hydrogen bonds to phosphate nonbridging oxygens. Results from an extensive set of MD simulations suggest that recent force field parametrizations improve predictions, but further improvements are necessary to provide reasonable agreement with NMR. In particular, intramolecular stacking and hydrogen bonding interactions may not be well balanced with the TIP3P water model. NMR data and the scoring method presented here provide rigorous benchmarks for future changes in force fields and MD methods. PMID:26082675

  4. TEM study on relationship between stacking faults and non-basal dislocations in Mg

    NASA Astrophysics Data System (ADS)

    Zhang, Dalong; Jiang, Lin; Schoenung, Julie M.; Mahajan, Subhash; Lavernia, Enrique J.

    2015-12-01

    Recent interest in the study of stacking faults and non-basal slip in Mg alloys is partly based on the argument that these phenomena positively influence mechanical behaviour. Inspection of the published literature, however, reveals that there is a lack of fundamental information on the mechanisms that govern the formation of stacking faults, especially I1-type stacking faults (I1 faults). Moreover, controversial and sometimes contradictory mechanisms have been proposed concerning the interactions between stacking faults and dislocations. Therefore, we describe a fundamental transmission electron microscope investigation on Mg 2.5 at. % Y (Mg-2.5Y) processed via hot isostatic pressing (HIP) and extrusion at 623 K. In the as-HIPed Mg-2.5Y, many and dislocations, together with some dislocations were documented, but no stacking faults were observed. In contrast, in the as-extruded Mg-2.5Y, a relatively high density of stacking faults and some non-basal dislocations were documented. Specifically, there were three different cases for the configurations of observed stacking faults. Case (I): pure I2 faults; Case (II): mixture of I1 faults and non-basal dislocations having component, together with basal dislocations; Case (III): mixture of predominant I2 faults and rare I1 faults, together with jog-like dislocation configuration. By comparing the differences in extended defect configurations, we propose three distinct stacking fault formation mechanisms for each case in the context of slip activity and point defect generation during extrusion. Furthermore, we discuss the role of stacking faults on deformation mechanisms in the context of dynamic interactions between stacking faults and non-basal slip.

  5. Debuncher Cooling Limitations to Stacking

    SciTech Connect

    Halling, Mike

    1991-08-13

    During the January studies period we performed studies to determine the effect that debuncher cooling has on the stacking rate. Two different sets of measurements were made separated by about a week. Most measurements reported here are in PBAR log 16, page 243-247. These measurements were made by changing the accelerator timeline to give about 6 seconds between 29's, and then gating the cooling systems to simulate reduced cycle times. For the measurement of the momentum cooling effectiveness the gating switches could not be made to work, so the timeline was changed for each measurement. The cooling power of all three systems was about 800 watts for the tests reported here. We now regularly run at 1200 watts per system.

  6. Stacked graphs--geometry & aesthetics.

    PubMed

    Byron, Lee; Wattenberg, Martin

    2008-01-01

    In February 2008, the New York Times published an unusual chart of box office revenues for 7500 movies over 21 years. The chart was based on a similar visualization, developed by the first author, that displayed trends in music listening. This paper describes the design decisions and algorithms behind these graphics, and discusses the reaction on the Web. We suggest that this type of complex layered graph is effective for displaying large data sets to a mass audience. We provide a mathematical analysis of how this layered graph relates to traditional stacked graphs and to techniques such as ThemeRiver, showing how each method is optimizing a different "energy function". Finally, we discuss techniques for coloring and ordering the layers of such graphs. Throughout the paper, we emphasize the interplay between considerations of aesthetics and legibility. PMID:18988970

  7. Performance evaluation of PEFC stack

    SciTech Connect

    Fujita, Jun-ichi; Ohtsuki, Jitsuji; Shindo, Yoshihiko

    1996-12-31

    Polymer electrolyte fuel cells (PEFCs) have many advantages such as high current density, short start-up time and endurance for start-stop cycles. Making use of these advantages, Fuji Electric has been working with the Kansai Electric Power Co., Inc. to explore practical applications of PEFCs for an electric utility use. Since large-sized electrodes are required in the electric utility applications, we have fabricated 600cm{sup 2} membrane-electrode assemblies by using hot-press method. We have also designed a cell structure to realize a uniform reaction over the electrodes. The structure includes a properly-shaped gas flow channel, a temperature-gradient cooling system. Using the 600cm{sup 2} (25x24cm) electrodes, a 30-cell stack (5kW) were constructed and tested.

  8. Project W-420 stack monitoring system upgrades

    SciTech Connect

    CARPENTER, K.E.

    1999-02-25

    This project will execute the design, procurement, construction, startup, and turnover activities for upgrades to the stack monitoring system on selected Tank Waste Remediation System (TWRS) ventilation systems. In this plan, the technical, schedule, and cost baselines are identified, and the roles and responsibilities of project participants are defined for managing the Stack Monitoring System Upgrades, Project W-420.

  9. Excitation transfer in stacked quantum dot chains

    NASA Astrophysics Data System (ADS)

    Kanjanachuchai, Songphol; Xu, Ming; Jaffré, Alexandre; Jittrong, Apichart; Chokamnuai, Thitipong; Panyakeow, Somsak; Boutchich, Mohamed

    2015-05-01

    Stacked InAs quantum dot chains (QDCs) on InGaAs/GaAs cross-hatch pattern (CHP) templates yield a rich emission spectrum with an unusual carrier transfer characteristic compared to conventional quantum dot (QD) stacks. The photoluminescent spectra of the controlled, single QDC layer comprise multiple peaks from the orthogonal QDCs, the free-standing QDs, the CHP, the wetting layers and the GaAs substrate. When the QDC layers are stacked, employing a 10 nm GaAs spacer between adjacent QDC layers, the PL spectra are dominated by the top-most stack, indicating that the QDC layers are nominally uncoupled. Under high excitation power densities when the high-energy peaks of the top stack are saturated, however, low-energy PL peaks from the bottom stacks emerge as a result of carrier transfers across the GaAs spacers. These unique PL signatures contrast with the state-filling effects in conventional, coupled QD stacks and serve as a means to quickly assess the presence of electronic coupling in stacks of dissimilar-sized nanostructures.

  10. Effective Stack Design in Air Pollution Control.

    ERIC Educational Resources Information Center

    Clarke, John H.

    1968-01-01

    Stack design problems fall into two general caterories--(1) those of building re-entry, and (2) those of general area pollution. Extensive research has developed adequate information, available in the literature, to permit effective stack design. A major roadblock to effective design has been the strong belief by architects and engineers that high…

  11. Spectroscopic signatures of AA' and AB stacking of chemical vapor deposited bilayer MoS2

    DOE PAGESBeta

    Xia, Ming; Li, Bo; Yin, Kuibo; Capellini, Giovanni; Niu, Gang; Gong, Yongji; Zhou, Wu; Ajayan, Pulickel M.; Xie, Ya -Hong

    2015-11-04

    We discuss prominent resonance Raman and photoluminescence spectroscopic differences between AA'and AB stacked bilayer molybdenum disulfide (MoS2) grown by chemical vapor deposition are reported. Bilayer MoS2 islands consisting of the two stacking orders were obtained under identical growth conditions. Also, resonance Raman and photoluminescence spectra of AA' and AB stacked bilayer MoS2 were obtained on Au nanopyramid surfaces under strong plasmon resonance. Both resonance Raman and photoluminescence spectra show distinct features indicating clear differences in interlayer interaction between these two phases. The implication of these findings on device applications based on spin and valley degrees of freedom.

  12. Spectroscopic Signatures of AA' and AB Stacking of Chemical Vapor Deposited Bilayer MoS2.

    PubMed

    Xia, Ming; Li, Bo; Yin, Kuibo; Capellini, Giovanni; Niu, Gang; Gong, Yongji; Zhou, Wu; Ajayan, Pulickel M; Xie, Ya-Hong

    2015-12-22

    Prominent resonance Raman and photoluminescence spectroscopic differences between AA' and AB stacked bilayer molybdenum disulfide (MoS2) grown by chemical vapor deposition are reported. Bilayer MoS2 islands consisting of the two stacking orders were obtained under identical growth conditions. Resonance Raman and photoluminescence spectra of AA' and AB stacked bilayer MoS2 were obtained on Au nanopyramid surfaces under strong plasmon resonance. Both resonance Raman and photoluminescence spectra show distinct features indicating clear differences in interlayer interaction between these two phases. The implication of these findings on device applications based on spin and valley degrees of freedom will be discussed. PMID:26536495

  13. A cross-stacked plasmonic nanowire network for high-contrast femtosecond optical switching

    NASA Astrophysics Data System (ADS)

    Lin, Yuanhai; Zhang, Xinping; Fang, Xiaohui; Liang, Shuyan

    2016-01-01

    We report an ultrafast optical switching device constructed by stacking two layers of gold nanowires into a perpendicularly crossed network, which works at a speed faster than 280 fs with an on/off modulation depth of about 22.4%. The two stacks play different roles in enhancing consistently the optical switching performance due to their different dependence on the polarization of optical electric fields. The cross-plasmon resonance based on the interaction between the perpendicularly stacked gold nanowires and its Fano-coupling with Rayleigh anomaly is the dominant mechanism for such a high-contrast optical switching device.

  14. Status of MCFC stack technology at IHI

    SciTech Connect

    Hosaka, M.; Morita, T.; Matsuyama, T.; Otsubo, M.

    1996-12-31

    The molten carbonate fuel cell (MCFC) is a promising option for highly efficient power generation possible to enlarge. IHI has been studying parallel flow MCFC stacks with internal manifolds that have a large electrode area of 1m{sup 2}. IHI will make two 250 kW stacks for MW plant, and has begun to make cell components for the plant. To improve the stability of stack, soft corrugated plate used in the separator has been developed, and a way of gathering current from stacks has been studied. The DC output potential of the plant being very high, the design of electric insulation will be very important. A 20 kW short stack test was conducted in 1995 FY to certificate some of the improvements and components of the MW plant. These activities are presented below.

  15. Modular fuel-cell stack assembly

    DOEpatents

    Patel, Pinakin

    2010-07-13

    A fuel cell assembly having a plurality of fuel cells arranged in a stack. An end plate assembly abuts the fuel cell at an end of said stack. The end plate assembly has an inlet area adapted to receive an exhaust gas from the stack, an outlet area and a passage connecting the inlet area and outlet area and adapted to carry the exhaust gas received at the inlet area from the inlet area to the outlet area. A further end plate assembly abuts the fuel cell at a further opposing end of the stack. The further end plate assembly has a further inlet area adapted to receive a further exhaust gas from the stack, a further outlet area and a further passage connecting the further inlet area and further outlet area and adapted to carry the further exhaust gas received at the further inlet area from the further inlet area to the further outlet area.

  16. Wind induced vibration of a stack

    SciTech Connect

    Chen, S.S.; Cai, Y.

    1992-12-01

    A stack supported by guy wires at four levels is subjected to large-amplitude oscillations when the wind speed is over 15 m/s. The excitation mechanisms are identified based on scoping calculations, analytical prediction using a finite element code, and observation of the stack/wire response. The stack is determined to be excited by vortex shedding. Once lock-in resonance occurs, the guy wires are excited by the transverse motion of the stack. Large-amplitude oscillations of the guy wires are due to parametric resonance. Several methods are recommended to alleviate vibrational problem for short-term and long-term solutions. A new stack which is modified based on the results of this study is not subjected to any unacceptable oscillations.

  17. Wind induced vibration of a stack

    SciTech Connect

    Chen, S.S.; Cai, Y.

    1992-01-01

    A stack supported by guy wires at four levels is subjected to large-amplitude oscillations when the wind speed is over 15 m/s. The excitation mechanisms are identified based on scoping calculations, analytical prediction using a finite element code, and observation of the stack/wire response. The stack is determined to be excited by vortex shedding. Once lock-in resonance occurs, the guy wires are excited by the transverse motion of the stack. Large-amplitude oscillations of the guy wires are due to parametric resonance. Several methods are recommended to alleviate vibrational problem for short-term and long-term solutions. A new stack which is modified based on the results of this study is not subjected to any unacceptable oscillations.

  18. Protocol for In Vitro Stacked Molecules Compatible with In Vivo Recombinase-Mediated Gene Stacking.

    PubMed

    Chen, Weiqiang; Ow, David W

    2016-01-01

    Previously, we described a method for a recombinase-directed stacking of new DNA to an existing transgenic locus. Here, we describe how we can similarly stack DNA molecules in vitro and that the in vitro derived gene stack can be incorporated into an Agrobacterium transformation vector by in vitro recombination. After transfer to the chromosome by Agroinfection, the transgenic locus harbors a new target site that can be used for the subsequent in vivo stacking of new DNA. Alternatively, the in vitro derived gene stack has the potential to be integrated directly into the plant genome in vivo at a preexisting chromosomal target. Being able to stack DNA in vitro as well as in vivo, and with compatibility between the two systems, brings new flexibility for using the recombinase-mediated approach for transgene stacking. PMID:27557684

  19. Barrier RF stacking at Fermilab

    SciTech Connect

    Weiren Chou et al.

    2003-06-04

    A key issue to upgrade the luminosity of the Tevatron Run2 program and to meet the neutrino requirement of the NuMI experiment at Fermilab is to increase the proton intensity on the target. This paper introduces a new scheme to double the number of protons from the Main Injector (MI) to the pbar production target (Run2) and to the pion production target (NuMI). It is based on the fact that the MI momentum acceptance is about a factor of four larger than the momentum spread of the Booster beam. Two RF barriers--one fixed, another moving--are employed to confine the proton beam. The Booster beams are injected off-momentum into the MI and are continuously reflected and compressed by the two barriers. Calculations and simulations show that this scheme could work provided that the Booster beam momentum spread can be kept under control. Compared with slip stacking, a main advantage of this new method is small beam loading effect thanks to the low peak beam current. The RF barriers can be generated by an inductive device, which uses nanocrystal magnet alloy (Finemet) cores and fast high voltage MOSFET switches. This device has been designed and fabricated by a Fermilab-KEK-Caltech team. The first bench test was successful. Beam experiments are being planned.

  20. Memory Stacking in Hierarchical Networks.

    PubMed

    Westö, Johan; May, Patrick J C; Tiitinen, Hannu

    2016-02-01

    Robust representations of sounds with a complex spectrotemporal structure are thought to emerge in hierarchically organized auditory cortex, but the computational advantage of this hierarchy remains unknown. Here, we used computational models to study how such hierarchical structures affect temporal binding in neural networks. We equipped individual units in different types of feedforward networks with local memory mechanisms storing recent inputs and observed how this affected the ability of the networks to process stimuli context dependently. Our findings illustrate that these local memories stack up in hierarchical structures and hence allow network units to exhibit selectivity to spectral sequences longer than the time spans of the local memories. We also illustrate that short-term synaptic plasticity is a potential local memory mechanism within the auditory cortex, and we show that it can bring robustness to context dependence against variation in the temporal rate of stimuli, while introducing nonlinearities to response profiles that are not well captured by standard linear spectrotemporal receptive field models. The results therefore indicate that short-term synaptic plasticity might provide hierarchically structured auditory cortex with computational capabilities important for robust representations of spectrotemporal patterns. PMID:26654206

  1. Carboxyl-peptide plane stacking is important for stabilization of buried E305 of Trichoderma reesei Cel5A.

    PubMed

    He, Chunyan; Chen, Jingfei; An, Liaoyuan; Wang, Yefei; Shu, Zhiyu; Yao, Lishan

    2015-01-26

    Hydrogen bonds or salt bridges are usually formed to stabilize the buried ionizable residues. However, such interactions do not exist for two buried residues D271 and E305 of Trichoderma reesei Cel5A, an endoglucanase. Mutating D271 to alanine or leucine improves the enzyme thermostability quantified by the temperature T50 due to the elimination of the desolvation penalty of the aspartic acid. However, the same mutations for E305 decrease the enzyme thermostability. Free energy calculations based on the molecular dynamics simulation predict the thermostability of D271A, D271L, and E305A (compared to WT) in line with the experimental observation but overestimate the thermostability of E305L. Quantum mechanical calculations suggest that the carboxyl-peptide plane stacking interactions occurring to E305 but not D271 are important for the carboxyl group stabilization. For the protonated carboxyl group, the interaction energy can be as much as about -4 kcal/mol for parallel stacking and about -7 kcal/mol for T-shaped stacking. For the deprotonated carboxyl group, the largest interaction energies for parallel stacking and T-shaped stacking are comparable, about -7 kcal/mol. The solvation effect generally weakens the interaction, especially for the charged system. A search of the carboxyl-peptide plane stacking in the PDB databank indicates that parallel stacking but not T-shaped stacking is quite common, and the most probable distance between the two stacking fragments is close to the value predicted by the QM calculations. This work highlights the potential role of carboxyl amide π-π stacking in the stabilization of aspartic acid and glutamic acid in proteins. PMID:25569819

  2. Molten carbonate fuel cell stack design options

    SciTech Connect

    Benjamin, T.G.; Petri, R.J.

    1986-01-01

    Significant strides in molten carbonate fuel cell (MCFC) life and performance have been made during the last 20 years. Results include single cell performance improvement from 10 watts/ft/sup 2/ to 120 watts/ft/sup 2/, testing of several sub-scale stacks, and significant reductions in cost. In the 1980s, attention has turned toward stack-related issues including component dimensional and structural stability, cathode dissolution, sulfur poisoning, hardware design, electrolyte management, carbon dioxide conservation, internal reforming, and systems considerations. This paper discusses MCFC stack hardware design options and present a brief introduction to MCFC technology. 4 refs., 8 figs.

  3. Molten carbonate fuel cell stack design options

    SciTech Connect

    Benjamin, T.G.; Petri, R.J.

    1986-03-01

    Significant strides in molten carbonate fuel cell (MCFC) life and performance have been made during the last 20 years. Results include single cell performance improvement from 10 watts/ft/sup 2/ to 120 watts/ft/sup 2/, testing of several sub-scale stacks, and significant reductions in cost. In the 1980's, attention has turned toward stack-related issues including component dimensional and structural stability, cathode dissolution, sulfur poisoning, hardware design, electrolyte management, carbon dioxide conservation, internal reforming, and systems considerations. This paper discusses MCFC stack hardware design options and present a brief introduction to MCFC technology. 4 references, 8 figures.

  4. Slip stacking experiments at Fermilab main injector

    SciTech Connect

    Kiyomi Koba et al.

    2003-06-02

    In order to achieve an increase in proton intensity, Fermilab Main Injector will use a stacking process called ''slip stacking''. The intensity will be doubled by injecting one train of bunches at a slightly lower energy, another at a slightly higher energy, then bringing them together for the final capture. Beam studies have started for this process and we have already verified that, at least for a low beam intensity, the stacking procedure works as expected. For high intensity operation, development work of the feedback and feedforward systems is under way.

  5. Parallel transport on principal bundles over stacks

    NASA Astrophysics Data System (ADS)

    Collier, Brian; Lerman, Eugene; Wolbert, Seth

    2016-09-01

    In this paper we introduce a notion of parallel transport for principal bundles with connections over differentiable stacks. We show that principal bundles with connections over stacks can be recovered from their parallel transport thereby extending the results of Barrett, Caetano and Picken, and Schreiber and Waldorf from manifolds to stacks. In the process of proving our main result we simplify Schreiber and Waldorf's original definition of a transport functor for principal bundles with connections over manifolds and provide a more direct proof of the correspondence between principal bundles with connections and transport functors.

  6. Dynamical Stability of Slip-stacking Particles

    SciTech Connect

    Eldred, Jeffrey; Zwaska, Robert

    2014-09-04

    We study the stability of particles in slip-stacking configuration, used to nearly double proton beam intensity at Fermilab. We introduce universal area factors to calculate the available phase space area for any set of beam parameters without individual simulation. We find perturbative solutions for stable particle trajectories. We establish Booster beam quality requirements to achieve 97% slip-stacking efficiency. We show that slip-stacking dynamics directly correspond to the driven pendulum and to the system of two standing-wave traps moving with respect to each other.

  7. Dynamical stability of slip-stacking particles

    NASA Astrophysics Data System (ADS)

    Eldred, Jeffrey; Zwaska, Robert

    2014-09-01

    We study the stability of particles in slip-stacking configuration, used to nearly double proton beam intensity at Fermilab. We introduce universal area factors to calculate the available phase space area for any set of beam parameters without individual simulation. We find perturbative solutions for stable particle trajectories. We establish Booster beam quality requirements to achieve 97% slip-stacking efficiency. We show that slip-stacking dynamics directly correspond to the driven pendulum and to the system of two standing-wave traps moving with respect to each other.

  8. Stacked vapor fed amtec modules

    DOEpatents

    Sievers, Robert K.

    1989-01-01

    The present invention pertains to a stacked AMTEC module. The invention includes a tubular member which has an interior. The member is comprised of a ion conductor that substantially conducts ions relative to electrons, preferably a beta"-alumina solid electrolyte, positioned about the interior. A porous electrode for conducting electrons and allowing sodium ions to pass therethrough, and wherein electrons and sodium ions recombine to form sodium is positioned about the beta"-alumina solid electrolyte. The electrode is operated at a temperature and a pressure that allows the recombined sodium to vaporize. Additionally, an outer current collector grid for distributing electrons throughout the porous electrode is positioned about and contacts the porous electrode. Also included in the invention is transporting means for transporting liquid sodium to the beta"-alumina solid electrolyte of the tubular member. A transition piece is positioned about the interior of the member and contacts the transporting means. The transition piece divides the member into a first cell and a second cell such that each first and second cell has a beta"-alumina solid electrolyte, a first and second porous electrode and a grid. The transition piece conducts electrons from the interior of the tubular member. There is supply means for supplying sodium to the transporting means. Preferably the supply means is a shell which surrounds the tubular member and is operated at a temperature such that the vaporized sodium condenses thereon. Returning means for returning the condensed sodium from the shell to the transporting means provides a continuous supply of liquid sodium to the transporting means. Also, there are first conducting means for conducting electric current from the transition piece which extends through the shell, and second conducting means for conducting electric current to the grid of the first cell which extends through the shell.

  9. Correlated lateral phase separations in stacks of lipid membranes

    SciTech Connect

    Hoshino, Takuma; Komura, Shigeyuki; Andelman, David

    2015-12-28

    Motivated by the experimental study of Tayebi et al. [Nat. Mater. 11, 1074 (2012)] on phase separation of stacked multi-component lipid bilayers, we propose a model composed of stacked two-dimensional Ising spins. We study both its static and dynamical features using Monte Carlo simulations with Kawasaki spin exchange dynamics that conserves the order parameter. We show that at thermodynamical equilibrium, due to strong inter-layer correlations, the system forms a continuous columnar structure for any finite interaction across adjacent layers. Furthermore, the phase separation shows a faster dynamics as the inter-layer interaction is increased. This temporal behavior is mainly due to an effective deeper temperature quench because of the larger value of the critical temperature, T{sub c}, for larger inter-layer interaction. When the temperature ratio, T/T{sub c}, is kept fixed, the temporal growth exponent does not increase and even slightly decreases as a function of the increased inter-layer interaction.

  10. Wearable solar cells by stacking textile electrodes.

    PubMed

    Pan, Shaowu; Yang, Zhibin; Chen, Peining; Deng, Jue; Li, Houpu; Peng, Huisheng

    2014-06-10

    A new and general method to produce flexible, wearable dye-sensitized solar cell (DSC) textiles by the stacking of two textile electrodes has been developed. A metal-textile electrode that was made from micrometer-sized metal wires was used as a working electrode, while the textile counter electrode was woven from highly aligned carbon nanotube fibers with high mechanical strengths and electrical conductivities. The resulting DSC textile exhibited a high energy conversion efficiency that was well maintained under bending. Compared with the woven DSC textiles that are based on wire-shaped devices, this stacked DSC textile unexpectedly exhibited a unique deformation from a rectangle to a parallelogram, which is highly desired in portable electronics. This lightweight and wearable stacked DSC textile is superior to conventional planar DSCs because the energy conversion efficiency of the stacked DSC textile was independent of the angle of incident light. PMID:24789065

  11. Characterization of Piezoelectric Stacks for Space Applications

    NASA Technical Reports Server (NTRS)

    Sherrit, Stewart; Jones, Christopher; Aldrich, Jack; Blodget, Chad; Bao, Xiaoqi; Badescu, Mircea; Bar-Cohen, Yoseph

    2008-01-01

    Future NASA missions are increasingly seeking to actuate mechanisms to precision levels in the nanometer range and below. Co-fired multilayer piezoelectric stacks offer the required actuation precision that is needed for such mechanisms. To obtain performance statistics and determine reliability for extended use, sets of commercial PZT stacks were tested in various AC and DC conditions at both nominal and high temperatures and voltages. In order to study the lifetime performance of these stacks, five actuators were driven sinusoidally for up to ten billion cycles. An automated data acquisition system was developed and implemented to monitor each stack's electrical current and voltage waveforms over the life of the test. As part of the monitoring tests, the displacement, impedance, capacitance and leakage current were measured to assess the operation degradation. This paper presents some of the results of this effort.

  12. Near-Earth Asteroid Stack - Mission Animation

    NASA Video Gallery

    A possible stack configuration - a deep space habitat, the Orion Multi-Purpose Crew Vehicle and Space Exploration Vehicle - approaches a near-Earth asteroid. During a mission that could take months...

  13. 40 CFR 61.33 - Stack sampling.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium § 61.33 Stack... Administrator. (d) All samples shall be analyzed and beryllium emissions shall be determined within 30...

  14. 40 CFR 61.33 - Stack sampling.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium § 61.33 Stack... results reported to the Administrator. (d) All samples shall be analyzed and beryllium emissions shall...

  15. 40 CFR 61.33 - Stack sampling.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium § 61.33 Stack... Administrator. (d) All samples shall be analyzed and beryllium emissions shall be determined within 30...

  16. 40 CFR 61.33 - Stack sampling.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium § 61.33 Stack... Administrator. (d) All samples shall be analyzed and beryllium emissions shall be determined within 30...

  17. 40 CFR 61.33 - Stack sampling.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium § 61.33 Stack... Administrator. (d) All samples shall be analyzed and beryllium emissions shall be determined within 30...

  18. On Understanding Stacking Fault Formation in Ice

    NASA Astrophysics Data System (ADS)

    Pirzadeh, Payman; Kusalik, Peter G.

    2012-12-01

    Despite dedicated efforts aimed at revealing possible molecular structures of the ice defects associated with stacking faults in ice (I), these molecular arrangements have remained a puzzle. Here we demonstrate how the reorganization of water molecules on different faces of ice (I) can facilitate formation of stacking faults within a crystal. We show that a pair of point defects can manifest a particular combination of coupled five- and eight-membered rings (5-8 rings). These structural motifs can facilitate a shift in layers within an ice (I) crystal, thereby inducing stacking faults. Furthermore, the presence of molecular solutes such as methane at the ice interface appears to trigger the formation of coupled 5-8 rings. The observation of such coupled 5-8 ring defects provides insights into the possible molecular mechanisms of stacking fault formation in ice (I) and has implications for ice crystal growth phenomenology and the consequent physical and chemical properties of ice.

  19. Molecular interactions of pesticides at the soil-water interface.

    PubMed

    Shirzadi, Azadeh; Simpson, Myrna J; Kumar, Rajeev; Baer, Andrew J; Xu, Yunping; Simpson, André J

    2008-08-01

    High-resolution magic angle spinning (HR-MAS) NMR spectroscopy combined with saturation-transfer double difference (STDD) NMR can be used to analyze the molecular-level interactions of pesticides and whole soils occurring at the soil-water interface. Here 1H HR-MAS STDD NMR has been applied to some common pesticides (trifluralin, acifluorfen, and (4-nitro-3-(trifluoromethyl) phenol) and a pesticide degradation product (1-naphthol). Results indicate that dipolar interactions, H-bonding, hydrophobic associations, and potentially pi-pi interactions are the predominant sorption mechanisms for these molecules at the soil-aqueous interface. It is evident that the physical and chemical characteristics of soil are highly influential in determining the mechanisms of pesticide sorption, as they significantly affect soil conformation. In particular, different binding mechanisms were observed for 1-naphthol in soil swollen using a buffer versus D2O, indicating that the K(oc) alone may not be enough to accurately predict the behavior of a molecule in a real soil environment. Preliminary kinetic-based studies suggest that both the swelling solvent and soil moisture content significantly influence the sequestration of trifluralin. These studies demonstrate that HR-MAS and STDD NMR are powerful and versatile tools which can be applied to expand our knowledge of the mechanistic interactions of agrochemicals at the molecular level. PMID:18754469

  20. Stack Characterization System Development and Testing

    SciTech Connect

    Noakes, Mark W; Lind, Randall F; Lloyd, Peter D; Pin, Francois G; Rowe, John C

    2011-01-01

    Oak Ridge National Laboratory, as well as the rest of the U.S. Department of Energy community, has numerous off-gas stacks that need to be decommissioned, demolished, and packaged for disposal. Disposal requires a waste disposition determination phase. Process knowledge typically makes a worst-case scenario decision that may place lower-level waste into a more expensive higher-level waste disposal category. Truly useful radiological and chemical sampling can be problematic on old stacks due to their inherent height and access hazards, and many of these stacks have begun to deteriorate structurally. A remote stack characterization system (SCS) that can manage sample and data collection removes people from the hazards and provides an opportunity for access to difficult to reach internal stack areas. The SCS is a remotely operated articulated radiological data recovery system designed to deploy down into off-gas stacks from the top via crane. The battery-powered SCS is designed to stabilize itself against the stack walls and move various data recovery systems into areas of interest on the inner stack walls. Stabilization is provided by a tripod structure; sensors are mounted in a rotatable bipod underneath the tripod. Sensors include a beta/gamma/alpha detector, a removable contaminant multi-sample automated sampler, and a multi-core remote core drill. Multiple cameras provide remote task viewing, support for sampling, and video documentation of the process. A delay in funding has delayed project delivery somewhat. Therefore, this paper describes the technology and shows fabrication and testing progress to the extent that data is available.

  1. Stacking fault energy in some single crystals

    NASA Astrophysics Data System (ADS)

    Vora, Aditya M.

    2012-06-01

    The stacking fault energy of single crystals has been reported using the peak shift method. Presently studied all single crystals are grown by using a direct vapor transport (DVT) technique in the laboratory. The structural characterizations of these crystals are made by XRD. Considerable variations are shown in deformation (α) and growth (β) probabilities in single crystals due to off-stoichiometry, which possesses the stacking fault in the single crystal.

  2. Cosmic ray test of INO RPC stack

    NASA Astrophysics Data System (ADS)

    Bhuyan, M.; Datar, V. M.; Kalmani, S. D.; Lahamge, S. M.; Mondal, N. K.; Nagaraj, P.; Pal, S.; Reddy, L. V.; Redij, A.; Samuel, D.; Saraf, M. N.; Satyanarayana, B.; Shinde, R. R.; Verma, P.

    2012-01-01

    The India-based Neutrino Observatory (INO) collaboration is planning to build a 50 kt magnetised iron calorimeter (ICAL) detector using glass Resistive Plate Chambers (RPCs) as active detector elements. A stack of 12 such glass RPCs of 1 m ×1 m in area is tracking cosmic ray muons for over three years. In this paper, we will review the constructional aspects of the stack and discuss the performance of the RPCs using this cosmic ray data.

  3. Multi-Stacked Supported Lipid Bilayer Micropatterning through Polymer Stencil Lift-Off.

    PubMed

    Zhu, Yujie; Negmi, Ahmed; Moran-Mirabal, Jose

    2015-01-01

    Complex multi-lamellar structures play a critical role in biological systems, where they are present as lamellar bodies, and as part of biological assemblies that control energy transduction processes. Multi-lamellar lipid layers not only provide interesting systems for fundamental research on membrane structure and bilayer-associated polypeptides, but can also serve as components in bioinspired materials or devices. Although the ability to pattern stacked lipid bilayers at the micron scale is of importance for these purposes, limited work has been done in developing such patterning techniques. Here, we present a simple and direct approach to pattern stacked supported lipid bilayers (SLBs) using polymer stencil lift-off and the electrostatic interactions between cationic and anionic lipids. Both homogeneous and phase-segregated stacked SLB patterns were produced, demonstrating that the stacked lipid bilayers retain lateral diffusivity. We demonstrate patterned SLB stacks of up to four bilayers, where fluorescence resonance energy transfer (FRET) and quenching was used to probe the interactions between lipid bilayers. Furthermore, the study of lipid phase behaviour showed that gel phase domains align between adjacent layers. The proposed stacked SLB pattern platform provides a robust model for studying lipid behaviour with a controlled number of bilayers, and an attractive means towards building functional bioinspired materials or devices. PMID:26343733

  4. Multi-Stacked Supported Lipid Bilayer Micropatterning through Polymer Stencil Lift-Off

    PubMed Central

    Zhu, Yujie; Negmi, Ahmed; Moran-Mirabal, Jose

    2015-01-01

    Complex multi-lamellar structures play a critical role in biological systems, where they are present as lamellar bodies, and as part of biological assemblies that control energy transduction processes. Multi-lamellar lipid layers not only provide interesting systems for fundamental research on membrane structure and bilayer-associated polypeptides, but can also serve as components in bioinspired materials or devices. Although the ability to pattern stacked lipid bilayers at the micron scale is of importance for these purposes, limited work has been done in developing such patterning techniques. Here, we present a simple and direct approach to pattern stacked supported lipid bilayers (SLBs) using polymer stencil lift-off and the electrostatic interactions between cationic and anionic lipids. Both homogeneous and phase-segregated stacked SLB patterns were produced, demonstrating that the stacked lipid bilayers retain lateral diffusivity. We demonstrate patterned SLB stacks of up to four bilayers, where fluorescence resonance energy transfer (FRET) and quenching was used to probe the interactions between lipid bilayers. Furthermore, the study of lipid phase behaviour showed that gel phase domains align between adjacent layers. The proposed stacked SLB pattern platform provides a robust model for studying lipid behaviour with a controlled number of bilayers, and an attractive means towards building functional bioinspired materials or devices. PMID:26343733

  5. Using $$X(3823)\\to J/\\psi\\pi^+\\pi^-$$ to Identify Coupled-Channel Effects

    DOE PAGESBeta

    Wang, Bo; Xu, Hao; Liu, Xiang; Chen, Dian-Yong; Coito, Susana; Eichten, Estia

    2016-03-17

    Very recently, a new charmonium-like state X(3823) was observed by the Belle and BESIII experiments, which is a good candidate of D-wave charmonium ψ(13D2). Since the X(3872) is just below the DD¯ * threshold, the decay X(3823) → J/ψπ+π - can be a golden channel to test the significance of coupled-channel effects. In this work, this decay is considered including both the hidden-charm dipion and the usual QCDME contributions. The partial decay width, the dipion invariant mass spectrum distribution dΓ[X(3823) → J/ψπ+π - ]/dmπ +π- , and the corresponding dΓ[X(3823) → J/ψπ+π- ]/d cos θ distribution are computed. Many parametersmore » are determined from existing experimental data, leaving the results mainly dependent on only one unknown phase between the QCDME and hidden-charm dipion amplitudes.« less

  6. Time-dependent amplitude analysis of $B^0 \\to K^0_S\\pi^ pi^-$

    SciTech Connect

    Aubert, B.

    2009-05-26

    In this paper we present results from a time-dependent amplitude analysis of the B{sup 0} {yields} K{sup 0}{sub s}{pi}{sup +}{pi}{sup -} decay. In Sec. II we describe the time-dependent DP formalism, and introduce the signal parameters that are extracted in the fit to data. In Sec. III we briefly describe the BABAR detector and the data set. In Sec. IV, we explain the selection requirements used to obtain the signal candidates and suppress backgrounds. In Sec. V we describe the fit method and the approach used to control experimental effects such as resolution. In Sec. VI we present the results of the fit, and extract parameters relevant to the contributing intermediate resonant states. In Sec. VII we discuss systematic uncertainties in the results, and finally we summarize the results in Sec. VIII.

  7. CP violation in the D0 -> pi+ pi- decay at CDF

    SciTech Connect

    Morello, Michael Joseph

    2010-12-01

    We report a measurement of the CP violating asymmetry in D{sup 0} {yields} {pi}{sup +}{pi}{sup -} decays using approximately 215,000 decays reconstructed in about 5.94 fb{sup -1} of CDF data. We use the strong D*{sup +} {yields} D{sup 0}{pi}{sup +} decay ('D* tag') to identify the flavor of the charmed meson at production time and exploit CP-conserving strong c{bar c} pair-production in p{bar p} collisions. Higher statistic samples of Cabibbo-favored D{sup 0} {yields} K{sup -}{pi}{sup +} decays with and without D* tag are used to highly suppress systematic uncertainties due to detector effects. The result, A{sub CP}(D{sup 0} {yields} {pi}{sup +}{pi}{sup -}) = [0.22 {+-} 0.24 (stat.) {+-} 0.11 (syst.)]%, is the world's most precise measurement to date and it is fully consistent with no CP violation.

  8. Precision Measurement of CP Violation in $D^0\\to\\pi^+\\pi^-$ at CDF

    SciTech Connect

    Di Canto, Angelo

    2010-11-01

    We report a preliminary measurement of the CP violating asymmetry in D{sup 0} {yields} {pi}{sup +}{pi}{sup -} using approximately 215,000 decays reconstructed in about 5.94/fb of CDF data. We use the strong D* {+-} D{sup 0}{pi}{sup +} decay (D* tag) to identify the flavor of the charmed meson at production time and exploit CP-conserving strong c-{bar c} pair-production in p-{bar p} collisions. Higher statistic samples of Cabibbo-favored D{sup 0} {yields} K{sup -}{pi}{sup +} decays with and without D* tag are used to highly suppress systematic uncertainties due to detector effects. The result is the world's most precise measurement to date.

  9. Dalitz-Plot Analysis of the Decays B+/- -> K+/- pi-/+ pi+/-

    SciTech Connect

    Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; Grauges, E.; Palano, A.; Pappagallo, M.; Pompili, A.; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; Eigen, G.; Ofte, I.; Stugu, B. /Bergen U. /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /Pisa U. /INFN, Pisa /Prairie View A-M /Princeton U. /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /University of South Carolina, Columbia, South Carolina 29208, USA /SLAC /Stanford U., Phys. Dept. /SUNY, Stony Brook /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Vanderbilt U. /Victoria U. /Warwick U. /Wisconsin U., Madison /Yale U. /Yale U. /Yale U. /Yale U. /Yale U. /Yale U. /Yale U. /Yale U. /Yale U. /Yale U. /Yale U. /Yale U. /Yale U. /Yale U. /Yale U. /Yale U. /Yale U. /Yale U. /Yale U. /Yale U. /Yale U.

    2005-10-04

    We report a Dalitz-plot analysis of the charmless hadronic decays of charged B mesons to the state K{sup {+-}} {pi}{sup {-+}}{pi}{sup {+-}}. Using a sample of 226.0 {+-} 2.5 million B{bar B}pairs collected by the BABAR detector, measure the magnitudes and phases of the intermediate resonant and nonresonant amplitudes both charge conjugate decays. We present measurements of the corresponding branching and their charge asymmetries that supersede those of previous BABAR analyses. We find the asymmetries to be consistent with zero.

  10. Amplitude Analysis of the Decay B0->K+pi-pi0

    SciTech Connect

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

    2008-09-03

    We report an updated amplitude analysis of the charmless hadronic decays of neutral B mesons to K{sup +} {pi}{sup -}{pi}{sup 0}. With a sample of 454 million {Upsilon}(4S) {yields} B{bar B} decays collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC, we measure the magnitudes and phases of the intermediate resonant and nonresonant amplitudes for B{sup 0} and B{sup 0} decays and determine the corresponding CP-averaged fit fractions and charge asymmetries.

  11. Search For the Highly Suppressed Decays B- -> K+ pi- pi- and B- -> K- K- pi+

    SciTech Connect

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

    2008-08-11

    The authors report a search for the decays B{sup -} {yields} K{sup +}{pi}{sup -}{pi}{sup -} and B{sup -} {yields} K{sup -}K{sup -}{pi}{sup +}, which are highly suppressed in the Standard Model. Using a sample of (467 {+-} 5) x 10{sup 6} B{bar B} pairs collected with the BABAR detector, they do not see any evidence of these decays and determine 90% confidence level upper limits of {Beta}(B{sup -} {yields} K{sup +}{pi}{sup -}{pi}{sup -}) < 9.5 x 10{sup -7} and {Beta}(B{sup -} {yields} K{sup -}K{sup -}{pi}{sup +}) < 1.6 x 10{sup -7} on the corresponding branching fractions, including systematic uncertainties.

  12. Search for tau- ---> 4pi- 3pi+ (pi0) nu/tau Decays

    SciTech Connect

    Ter-Antonian, R.; Kass, R.; Allmendinger, T.; Hast, C.; /SLAC

    2005-06-21

    A search for the decay of the {tau} lepton to seven charged pions and at most one {pi}{sup 0} was performed using the BABAR detector at the PEP-II e{sup +}e{sup -} collider. The analysis uses data recorded on and near the {Upsilon}(4S) resonance between 1999 and 2003, a total of 124.3 fb{sup -1}. They observe 7 events with an expected background of 11.9 {+-} 2.2 events and calculate a preliminary upper limit of BR({tau}{sup -} {yields} 4{pi}{sup -} 3{pi}{sup +}({pi}{sup 0}){nu}{sub {tau}}) < 2.7 x 10{sup -7} at 90% CL. This is a significant improvement over the previous limit established by the CLEO Collaboration.

  13. S-wave K- pi+ system in D+ ---> K- pi+ pi+ decays from Fermilab E791

    SciTech Connect

    Meadows, B.T.; /Cincinnati U.

    2005-06-01

    A new approach to the analysis of three body decays is presented. Model-independent results are obtained for the S-wave K{pi} amplitude as a function of K{pi} invariant mass. These are compared with results from K{sup -}{pi}{sup +} elastic scattering, and the prediction of the Watson theorem, that the phase behavior be the same below K{eta}' threshold, is tested. Contributions from I = 1/2 and I = 3/2 are not resolved in this study. If I = 1/2 dominates, however, the Watson theorem does not describe these data well.

  14. Measurement of the Branching Ratio Lambda_c+ -> p pi+ pi-

    SciTech Connect

    Lopez-Hinojosa, Guillermo; /San Luis Potosi U.

    2008-03-01

    The confirmation of the Cabibbo-suppressed charm baryon decay mode {Lambda}{sub c}{sup +} {yields} p{pi}{sup +}{pi}{sup -} is reported. All data analyzed are from SELEX, a fixed target experiment at Fermilab that took data during 1996 and 1997, mainly with a 600 GeV/c {Sigma}{sup -} beam. The branching ratio of the Cabibbo-suppressed decay mode {Lambda}{sub c}{sup +} {yields} p{pi}{sup +}{pi}{sup -} relative to the Cabibbo-favored mode {Lambda}{sub c}{sup +} {yields} pK{sup -}{pi}{sup +} is measured to be: {Gamma}({Lambda}{sub c}{sup +} {yields} p{pi}{sup +}{pi}{sup -})/{Gamma}({Lambda}{sub c}{sup +} {yields} pK{sup -}{pi}{sup +}) = 0.103 {+-} 0.022.

  15. Using $X(3823)\\to J/\\psi\\pi^+\\pi^-$ to Identify Coupled-Channel Effects

    SciTech Connect

    Wang, Bo; Xu, Hao; Liu, Xiang; Chen, Dian-Yong; Coito, Susana; Eichten, Estia

    2015-07-28

    Very recently, a new charmonium-like state X(3823) was observed by the Belle and BESIII experiments, which is a good candidate of D-wave charmonium ψ(13D2). Since the X(3872) is just below the DD¯ * threshold, the decay X(3823) → J/ψπ+π - can be a golden channel to test the significance of coupled-channel effects. In this work, this decay is considered including both the hidden-charm dipion and the usual QCDME contributions. The partial decay width, the dipion invariant mass spectrum distribution dΓ[X(3823) → J/ψπ+π - ]/dmπ +π- , and the corresponding dΓ[X(3823) → J/ψπ+π- ]/d cos θ distribution are computed. Many parameters are determined from existing experimental data, leaving the results mainly dependent on only one unknown phase between the QCDME and hidden-charm dipion amplitudes.

  16. Dalitz-plot Analysis of B0 -> anti-D0 pi pi-

    SciTech Connect

    del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Battaglia, M.; Brown, David Nathan; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; Tanabe, T.; /more authors..

    2010-08-25

    The authors report preliminary results from a study of the decay B{sup 0} {yields} {bar D}{sup 0}{pi}{sup +}{pi}{sup -} using a data sample of 470.9 {+-} 2.8 million B{bar B} events collected with the BABAR detector at the {Upsilon}(4S) resonance. Using the Dalitz-plot analysis technique, they find contributions from the intermediate resonances D*{sub 2}(2460){sup -}, D*{sub 0}(2400){sup -}, {rho}(770){sup 0} and f{sub 2}(1270) as well as a {pi}{sup +}{pi}{sup -} S-wave term, a {bar D}{sup 0}{pi}{sup -} nonresonant S-wave term and a virtual D*(2010) amplitude. They measure the branching fractions of the contributing decays.

  17. Measurement of direct photon emission in the K(L) ---> pi+ pi- gamma decay mode

    SciTech Connect

    Abouzaid, E.; Arenton, M.; Barker, A.R.; Bellantoni, L.; Bellavance, A.; Blucher, E.; Bock, G.J.; Cheu, E.; Coleman, R.; Corcoran, M.D.; Corti, G.; /Virginia U. /Wisconsin U., Madison

    2006-04-01

    In this paper the KTeV collaboration reports the analysis of 112.1 x 10{sup 3} candidate K{sub L} {yields} {pi}{sup +}{pi}{sup -}{gamma} decays including a background of 671 {+-} 41 events with the objective of determining the photon production mechanisms intrinsic to the decay process. These decays have been analyzed to extract the relative contributions of the Cp violating bremsstrahlung process and the CP conserving M1 and CP violating E1 direct photon emission processes. The M1 direct photon emission amplitude and its associated vector form factor parameterized as |{bar g}{sub M1}|(1 + a{sub 1}/a{sub 2}/(M{sub {rho}}{sup 2}-M{sub K}{sup 2}) + 2M{sub K}E{sub {gamma}}) have been measured to be |{bar g}{sub M1}| = 1.198 {+-} 0.035(stat) {+-} 0.086(syst) and a{sub 1}/a{sub 2} = =0.738 {+-} 0.007(stat) {+-} 0.018(syst) GeV{sup 2}/c{sup 2} respectively. An upper limit for the CP violating E1 direct emission amplitude |g{sub E1}| {le} 0.1 (90%CL) has been found. The overall ratio of direct photon emission (DE) to total photon emission including the bremsstrahlung process (IB) has been determined to be DE/(DE + IB) = 0.689 {+-} 0.021 for E{sub {gamma}} {ge} 20 MeV.

  18. Branching Fraction and Charge Asymmetry Measurements inB to J/psi pi pi Decays

    SciTech Connect

    Aubert, B.; Bona, M.; Boutigny, D.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prudent, X.; Tisserand, V.; Zghiche, A.; Garra Tico, J.; Grauges, E.; Lopez, L.; Palano, A.; Eigen, G.; Ofte, I.; Stugu, B.; Sun, L.; Abrams, G.S.; Battaglia, M.; Brown, D.N.; Button-Shafer, J.; /LBL, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Munich, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /Frascati /Genoa U. /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Karlsruhe U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Maryland U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /Paris U., VI-VII /Pennsylvania U. /Perugia U. /Pisa U. /Prairie View A-M /Princeton U. /INFN, Rome /Rostock U. /Rutherford /DSM, DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /Trieste U. /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison /Yale U.

    2007-04-16

    The authors study the decays B{sup 0} {yields} J/{psi} {pi}{sup +}{pi}{sup -} and B{sup +} {yields} J/{psi} {pi}{sup +}{pi}{sup 0}, including intermediate resonances, using a sample of 382 million B{bar B} pairs recorded by the BABAR detector at the PEP-II e{sup +}e{sup -} B factory. They measure the branching fractions {Beta}(B{sup 0} {yields} J/{psi} {rho}{sup 0}) = (2.7 {+-} 0.3 {+-} 0.17) x 10{sup -5} and {Beta}(B{sup +} {yields} J/{psi} {rho}{sup +}) = (5.0 {+-} 0.7 {+-} 0.31) x 10{sup -5}. The authors also set the following upper limits at the 90% confidence level: {Beta}(B{sup 0} {yields} J/{psi} {pi}{sup +}{pi}{sup -} non-resonant) < 1.2 x 10{sup -5}, {Beta}(B{sup 0} {yields} J/{psi} f{sub 2}) < 4.6 x 10{sup -6}, and {Beta}(B{sup +} {yields} J/{psi} {pi}{sup +}{pi}{sup 0} non-resonant) < 4.4 x 10{sup -6}. They measure the charge asymmetry in charged B decays to J/{psi} {rho} to be -0.11 {+-} 0.12 {+-} 0.08.

  19. Search for b to u transitions in B- to [K+pi-pi0]_D K-

    SciTech Connect

    Aubert, B.; Barate, R.; Bona, M.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; Grauges, E.; Palano, A.; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; Eigen, G.; Ofte, I.; Stugu, B.; Abrams, G.S.; /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Karlsruhe U., EKP /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Pennsylvania U. /Perugia U. /INFN, Perugia /Pisa U. /INFN, Pisa /Prairie View A-M /Princeton U. /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Stony Brook /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison /Yale U.

    2006-12-06

    The authors search for decays of a B meson into a neutral D meson and a kaon, with the D meson decaying into K{sup +}{pi}{sup -}{pi}{sup 0}. This final state can be reached through the b {yields} c transition B{sup -} {yields} D{sup 0}K{sup -} followed by the doubly Cabibbo-suppressed D{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0}, or the b {yields} u transition B{sup -} {yields} {bar D}{sup 0}K{sup -} followed by the Cabibbo-favored {bar D}{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0}. The interference of these two amplitudes is sensitive to the angle {gamma} of the unitarity triangle. They present preliminated results based on 226 x 10{sup 6} e{sup +}e{sup -} {yields} {Upsilon}(4S) {yields} B{bar B} events collected with the BABAR detector at SLAC.

  20. Measurement of the dipion mass spectrum in X(3872) ---> J/psi pi+ pi- decays

    SciTech Connect

    Abulencia, A.; Acosta, D.; Adelman, Jahred A.; Affolder, Anthony A.; Akimoto, T.; Albrow, M.G.; Ambrose, D.; Amerio, S.; Amidei, D.; Anastassov, A.; Anikeev, K.; /Taiwan, Inst. Phys. /Argonne /Barcelona, IFAE /Baylor U. /INFN, Bologna /Bologna U. /Brandeis U. /UC, Davis /UCLA /UC, San Diego /UC, Santa Barbara

    2005-12-01

    The authors measure the dipion mass spectrum in X(3872) {yields} J/{psi}{pi}{sup +}{pi}{sup -} decays using 360 pb{sup -1} of {bar p}p collisions at {radical}s = 1.96 TeV collected with the CDF II detector. The spectrum is fit with predictions for odd C-parity ({sup 3}S{sub 1}, {sup 1}P{sub 1}, and {sup 3}D{sub J}) charmonia decaying to J/{psi}{pi}{sup +}{pi}{sup -}, as well as event C-parity states in which the pions are from {rho}{sup 0} decay. The latter case also encompasses exotic interpretations, such as a D{sup 0}{bar D}*{sup 0} molecule. Only the {sup 3}S{sub 1} and J/{psi} {rho} hypotheses are compatible with the data. Since {sup 3}S{sub 1} is untenable on other grounds, decay via J/{psi} {rho} is favored, which implies C = +1 for the X(3872). Models for different J/{psi}-{rho} angular momenta L are considered. Flexibility in the models, especially the introduction of {rho}-{omega} interference, enable good descriptions of the data for both L = 0 and 1.

  1. Rare decay {eta}{r_arrow}{pi}{pi}{gamma}{gamma} in chiral perturbation theory

    SciTech Connect

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

    1996-04-01

    We investigate the rare radiative {eta} decay modes {eta}{r_arrow}{pi}{sup +}{pi}{sup {minus}}{gamma}{gamma} and {eta}{r_arrow}{pi}{sup 0}{pi}{sup 0}{gamma}{gamma} within the framework of chiral perturbation theory at {ital O}({ital p}{sup 4}). We present photon spectra and partial decay rates for both processes as well as a Dalitz contour plot for the charged decay. {copyright} {ital 1996 The American Physical Society.}

  2. Measurement of the D+ -> pi+pi0 and D+ -> K+pi0Branching Fractions

    SciTech Connect

    Aubert, B.

    2006-07-21

    We present measurements of the branching fractions for the Cabbibo suppressed decays D{sup +} {yields} {pi}{sup +}{pi}{sup 0} and D{sup +} {yields} K{sup +}{pi}{sup 0} based on a data sample corresponding to an integrated luminosity of 124.3 fb{sup -1}. The data were taken with the BABAR detector at the PEP-II B Factory operating on and near the {Upsilon}(4S) resonance. We find {Beta}(D{sup +} {yields} {pi}{sup +}{pi}{sup 0}) = (1.25 {+-} 0.10 {+-} 0.09 {+-} 0.04) x 10{sup -3} and {Beta}(D{sup +} {yields} K{sup +}{pi}{sup 0}) = (2.52 {+-} 0.47 {+-} 0.25 {+-} 0.08) x 10{sup -4}, where the first uncertainty is statistical, the second systematic and the last error is due to the uncertainties in the absolute branching fraction scale for D{sup +} mesons. This represents the first observation of the doubly Cabibbo-suppressed D{sup +} {yields} K{sup +}{pi}{sup 0} decay mode and a new measurement of the D{sup +} {yields} {pi}{sup +}{pi}{sup 0} branching fraction.

  3. Dalitz Plot Analysis of the Decay B0(B0bar) to K^+/- pi^-/+ pi0

    SciTech Connect

    Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prudent, X.; Tisserand, V.; Zghiche, A.; Garra Tico, J.; Grauges, E.; Lopez, L.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Abrams, G.S.; Battaglia, M.; Brown, D.N.; Button-Shafer, J.; Cahn, R.N.; /Energy Sci. Network /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Karlsruhe U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /Pisa U. /Pisa, Scuola Normale Superiore /INFN, Pisa /Princeton U. /Rome U. /INFN, Rome /Rostock U. /Rutherford /DSM, DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison /Yale U.

    2008-09-18

    The authors report a Dalitz-plot analysis of the charmless hadronic decays of neutral B mesons to K{sup {+-}}{pi}{sup {-+}}{pi}{sup 0}. With a sample of (231.8 {+-} 2.6) x 10{sup 6}{Upsilon}(4S) {yields} B{bar B} decays collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC, they measure the magnitudes and phases of the intermediate resonant and nonresonant amplitudes for B{sup 0} and {bar B}{sup 0} decays and determine the corresponding CP-averaged branching fractions and charge asymmetries. The inclusive branching fraction and CP-violating charge asymmetry are measured to be {Beta}(B{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0}) = (35.7{sub -1.5}{sup +2.6} {+-} 2.2) x 10{sup -6}, and {Alpha}{sub CP} = -0.030{sub -0.051}{sup +0.045} {+-} 0.055 where the first errors are statistical and the second systematic. They observe the decay B{sup 0} {yields} K*{sup 0}(892){pi}{sup 0} with the branching fraction {Beta}(B{sup 0} {yields} K*{sup 0}(892){pi}{sup 0}) = (3.6{sub -0.8}{sup +0.7} {+-} 0.4) x 10{sup -6}. This measurement differs from zero by 5.6 standard deviations (including the systematic uncertainties). The selected sample also contains B{sup 0} {yields} {bar D}{sup 0}{pi}{sup 0} decays where {bar D}{sup 0} {yields} K{sup +}{pi}{sup -}, and they measure {Beta}(B{sup 0} {yields} {bar D}{sup 0}{pi}{sup 0}) = (2.93 {+-} 0.17 {+-} 0.18) x 10{sup -4}.

  4. Search for b --> u Transitions in B^{+-} --> [K^{-+} pi^{+-} pi0]_D K^{+-} Decays

    SciTech Connect

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

    2011-08-12

    The authors present a study of the decays B{sup {+-}} {yields} DK{sup {+-}} with D mesons reconstructed in the K{sup +}{pi}{sup -}{pi}{sup 0} or K{sup -}{pi}{sup +}{pi}{sup 0} final states, where D indicates a D{sup 0} or a {bar D}{sup 0} meson. Using a sample of 474 million B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at SLAC, they measure the ratios R{sup {+-}} {triple_bond} {Lambda}(B{sup {+-}}{yields}[K{sup {-+}}{pi}{sup {+-}}{pi}{sup 0}]{sub D}K{sup {+-}})/{Lambda}(B{sup {+-}}{yields}[K{sup {+-}}{pi}{sup {-+}}{pi}{sup 0}]{sub D}K{sup {+-}}). They obtain R{sup +} = (5{sub -10}{sup +12}(stat){sub -4}{sup +2}(syst)) x 10{sup -3} and R{sup -} = (12{sub -10}{sup +12}(stat){sub -5}{sup +3}(syst)) x 10{sup -3}, from which they extract the upper limits at 90% probability: R{sup +} < 23 x 10{sup -3} and R{sup -} < 29 x 10{sup -3}. Using these measurements, they obtain an upper limit for the ratio r{sub B} of the magnitudes of the b {yields} u and b {yields} c amplitudes r{sub B} < 0.13 at 90% probability.

  5. Vortex Penetrations in Parallel-connected two Stacks of Intrinsic Josephson Junctions

    NASA Astrophysics Data System (ADS)

    Ooi, Shuuichi; Mochiku, Takashi; Tachiki, Minoru; Hirata, Kazuto

    In mesoscopic stacks of intrinsic Josephson junctions (IJJs) in Bi2Sr2CaCu2O8+y (Bi2212), the penetrations of individual vortices are detectable by the measurements of the transport properties, i.e., c-axis resistance or critical current. We have measured the c-axis resistance as a function of magnetic field in samples with two stacks of IJJs connected in parallel by Bi2212 itself to study any interaction of individual vortex penetrations into them. Since the superconducting loop containing two stacks of IJJs is the same geometry as that of superconducting quantum interference device (SQUID), we might expect a periodic resistance (or current) modulation as a function of magnetic field, whose period corresponds to the area in the loop. However, the results were just simple mixing of the resistive changes by the individual vortex penetrations into each of the stacks; behavior like SQUID has not been observed in present samples.

  6. Stacked subwavelength gratings for imaging polarimetry

    NASA Astrophysics Data System (ADS)

    Deguzman, Panfilo Castro

    The stacking of subwavelength gratings (SWG) in an integrated structure is presented for an application in imaging polarimetry. Imaging polarimetry extends the capability of conventional imaging by providing polarization information about a scene, in addition to variations in intensity. In this dissertation, a novel approach is introduced to develop a real-time imaging polarimeter. Subwavelength gratings are implemented as linear and circular polarization filters that are directly mounted onto the focal plane array of an infrared (IR) camera. Wire grid polarizers are used as linear polarization filters. The stacked structure, consisting of a wire grid polarizer and a form birefringent quarter-wave plate (QWP), implements the circular polarization filter and is the focus of this dissertation. Initial investigations of the development of the individual SWG components and their integration are presented. Rigorous Coupled Wave Analysis (RCWA) was used to design the SWG structures. A broadband form birefringent quarter-wave plate for the 3.5 to 5 μm wavelength range was designed as a grating structure patterned directly into the substrate. Two fabrication methods for the wire grid polarizer were investigated. A 0.5 μm period polarizer was patterned by interference lithography. A 1 μm period polarizer was patterned by contact printing. The stacking of the subwavelength grating structures was analyzed using the Jones Matrix calculus and a new RCWA method (developed by fellow graduate student Jianhua Jiang). Stacked SWG's were fabricated as large area (1.3 cm x 1.3 cm) filters and as a 256 x 256 array of small aperture (15 μm x 15 μm) pixels. Two stack designs were investigated, referred to as Stack I and Stack II. Stack I consisted of the 0.5 μm period polarizer and the form birefringent QWP. Stack II consisted of the I μm grid period polarizer and the form birefringent QWP. Simulation and measured results are presented to compare the cases of samples with and

  7. Energy level alignment in Au/pentacene/PTCDA trilayer stacks

    NASA Astrophysics Data System (ADS)

    Sehati, P.; Braun, S.; Fahlman, M.

    2013-09-01

    Ultraviolet photoelectron spectroscopy is used to investigate the energy level alignment and molecular orientation at the interfaces in Au/pentacene/PTCDA trilayer stacks. We deduced a standing orientation for pentacene grown on Au while we conclude a flat lying geometry for PTCDA grown onto pentacene. We propose that the rough surface of polycrystalline Au induces the standing geometry in pentacene. It is further shown that in situ deposition of PTCDA on pentacene can influence the orientation of the surface pentacene layer, flipping part of the surface pentacene molecules into a flat lying geometry, maximizing the orbital interaction across the pentacene-PTCDA heterojunction.

  8. Symmetry and resonant modes in platonic grating stacks

    NASA Astrophysics Data System (ADS)

    Haslinger, S. G.; Movchan, A. B.; Movchan, N. V.; McPhedran, R. C.

    2014-04-01

    We study the flexural wave modes existing in finite stacks of gratings containing rigid, zero-radius pins. We group the modes into even and odd classes, and derive dispersion equations for each. We study the recently discovered elasto-dynamically inhibited transmission (EDIT) phenomenon, and relate it to the occurrence of trapped waves of even and odd symmetries being simultaneously resonant. We show how the EDIT interaction may be steered over a wide range of frequencies and angles, using a strategy in which the single-grating reflectance is kept high, so enabling the quality factors of the even and odd resonances to be kept large.

  9. Manifold gasket accommodating differential movement of fuel cell stack

    SciTech Connect

    Kelley, Dana A.; Farooque, Mohammad

    2007-11-13

    A gasket for use in a fuel cell system having at least one externally manifolded fuel cell stack, for sealing the manifold edge and the stack face. In accordance with the present invention, the gasket accommodates differential movement between the stack and manifold by promoting slippage at interfaces between the gasket and the dielectric and between the gasket and the stack face.

  10. Principles for Instructional Stack Development in HyperCard.

    ERIC Educational Resources Information Center

    McEneaney, John E.

    The purpose of this paper is to provide information about obtaining and using HyperCard stacks that introduce users to principles of stack development. The HyperCard stacks described are available for downloading free of charge from a server at Indiana University South Bend. Specific directions are given for stack use, with advice for beginners. A…

  11. Stacking dependent electronic structures of transition metal dichalcogenides heterobilayer

    NASA Astrophysics Data System (ADS)

    Lee, Yea-Lee; Park, Cheol-Hwan; Ihm, Jisoon

    The systematic study of the electronic structures and optical properties of the transition metal dichalcogenides (TMD) heterobilayers can significantly improve the designing of new electronic and optoelectronic devices. Here, we theoretically study the electronic structures and optical properties of TMD heterobilayers using the first-principles methods. The band structures of TMD heterobilayer are shown to be determined by the band alignments of the each layer, the weak interlayer interactions, and angle dependent stacking patterns. The photoluminescence spectra are investigated using the calculated band structures, and the optical absorption spectra are examined by the GW approximations including the electron-hole interaction through the solution of the Bethe-Salpeter equation. It is expected that the weak interlayer interaction gives rise to the substantial interlayer optical transition which will be corresponding to the interlayer exciton.

  12. Stacking of Interferometric Data: New Tools for Stacking of ALMA Data

    NASA Astrophysics Data System (ADS)

    Knudsen, K. K.; Lindroos, L.; Vlemmings, W.; Conway, J.; Martí-Vidal, I.

    2015-12-01

    Radio and mm observations play an important role in determining the star formation properties of high-redshift galaxies. With the unprecedented sensitivity, ALMA now enable studies of faint , distant star-forming galaxies. However, most galaxies with low star formation rates at high redshift are too faint to be detected individually at these wavelengths. A way to study such galaxies is to use stacking. By averaging the emission of a large number of galaxies detected in optical or near-infrared surveys, we can achieve statistical detection. We investigate methods for stacking data from interferometric surveys. Interferometry poses unique challenges in stacking due to the nature of this data. We have compared stacking of uv-data with stacking of imaged data, the latter being the commonly used approach. Using simulated data, we find that uv-stacking may provide up to 50% less noise and that image based stacking systematically loses around 10% of the flux. More importantly, we find that the uv-stacking yield more robust results, especially in the case of (marginally) resolved sources and mosaicked data.

  13. Contemporary sample stacking in analytical electrophoresis.

    PubMed

    Malá, Zdena; Šlampová, Andrea; Křivánková, Ludmila; Gebauer, Petr; Boček, Petr

    2015-01-01

    This contribution is a methodological review of the publications about the topic from the last 2 years. Therefore, it is primarily organized according to the methods and procedures used in surveyed papers and the origin and type of sample and specification of analytes form the secondary structure. The introductory part about navigation in the architecture of stacking brings a brief characterization of the various stacking methods, with the description of mutual links to each other and important differences among them. The main body of the article brings a survey of publications organized according to main principles of stacking and then according to the origin and type of the sample. Provided that the paper cited gave explicitly the relevant data, information about the BGE(s) used, procedure, detector employed, and reached LOD and/or concentration effect is given. The papers where the procedure used is a combination of diverse fragments and parts of various stacking techniques are mentioned in a special section on combined techniques. The concluding remarks in the final part of the review evaluate present state of art and the trends of sample stacking in CE. PMID:25113855

  14. A Late Pleistocene sea level stack

    NASA Astrophysics Data System (ADS)

    Spratt, Rachel M.; Lisiecki, Lorraine E.

    2016-04-01

    Late Pleistocene sea level has been reconstructed from ocean sediment core data using a wide variety of proxies and models. However, the accuracy of individual reconstructions is limited by measurement error, local variations in salinity and temperature, and assumptions particular to each technique. Here we present a sea level stack (average) which increases the signal-to-noise ratio of individual reconstructions. Specifically, we perform principal component analysis (PCA) on seven records from 0 to 430 ka and five records from 0 to 798 ka. The first principal component, which we use as the stack, describes ˜ 80 % of the variance in the data and is similar using either five or seven records. After scaling the stack based on Holocene and Last Glacial Maximum (LGM) sea level estimates, the stack agrees to within 5 m with isostatically adjusted coral sea level estimates for Marine Isotope Stages 5e and 11 (125 and 400 ka, respectively). Bootstrapping and random sampling yield mean uncertainty estimates of 9-12 m (1σ) for the scaled stack. Sea level change accounts for about 45 % of the total orbital-band variance in benthic δ18O, compared to a 65 % contribution during the LGM-to-Holocene transition. Additionally, the second and third principal components of our analyses reflect differences between proxy records associated with spatial variations in the δ18O of seawater.

  15. Technical description of Stack 296-B-5

    SciTech Connect

    Ridge, T.M.

    1994-11-15

    Of particular concern to facilities on the Hanford site is Title 40, Code of Federal Regulations, Chapter 40, Part 61, Subpart H, ``National emission Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities.`` Assessments of facility stacks and potential radionuclide emissions determined whether these stacks would be subject to the sampling and monitoring requirements of 40 CFR 61, Subpart H. Stack 296-B-5 exhausts 221-BB building which houses tanks containing B Plant steam condensate and B Plant process condensate from the operation of the low-level waste concentrator. The assessment of potential radionuclide emissions from the 296-B-5 stack resulted in an effective dose equivalent to the maximally exposed individual of less than 0.1 millirem per year. Therefore, the stack is not subject to the sampling and monitoring requirements of 40 CFR 61, Subpart H. However, the sampling and monitoring system must be in compliance with the Environmental Compliance Manual, WHC-CM-7-5. Currently, 296-B-5 is sampled continuously with a record sampler and continuous air monitor (CAM).

  16. Inflatable containment diaphragm for sealing and removing stacks

    DOEpatents

    Meskanick, Gerald R.; Rosso, David T.

    1993-01-01

    A diaphragm with an inflatable torus-shaped perimeter is used to seal at least one end of a stack so that debris that might be hazardous will not be released during removal of the stack. A diaphragm is inserted and inflated in the lower portion of a stack just above where the stack is to be cut such that the perimeter of the diaphragm expands and forms a seal against the interior surface of the stack.

  17. Inflatable containment diaphragm for sealing and removing stacks

    DOEpatents

    Meskanick, G.R.; Rosso, D.T.

    1993-04-13

    A diaphragm with an inflatable torus-shaped perimeter is used to seal at least one end of a stack so that debris that might be hazardous will not be released during removal of the stack. A diaphragm is inserted and inflated in the lower portion of a stack just above where the stack is to be cut such that the perimeter of the diaphragm expands and forms a seal against the interior surface of the stack.

  18. Ab-initio calculation of electronic structure and optical properties of AB-stacked bilayer α-graphyne

    NASA Astrophysics Data System (ADS)

    Behzad, Somayeh

    2016-09-01

    Monolayer α-graphyne is a new two-dimensional carbon allotrope with many special features. In this work the electronic properties of AA- and AB-stacked bilayers of this material and then the optical properties are studied, using first principle plane wave method. The electronic spectrum has two Dirac cones for AA stacked bilayer α-graphyne. For AB-stacked bilayer, the interlayer interaction changes the linear bands into parabolic bands. The optical spectra of the most stable AB-stacked bilayer closely resemble to that of the monolayer, except for small shifts of peak positions and increasing of their intensity. For AB-stacked bilayer, a pronounced peak has been found at low energies under the perpendicular polarization. This peak can be clearly ascribed to the transitions at the Dirac point as a result of the small degeneracy lift in the band structure.

  19. Characterization of noncovalent interactions between 6-propionyl-2-dimethylaminonaphthalene (PRODAN) and dissolved fulvic and humic acids.

    PubMed

    Gadad, Praveen; Lei, Hongxia; Nanny, Mark A

    2007-11-01

    Noncovalent interactions between the fluorescent probe 6-propionyl-2-dimethylaminonaphthalene (PRODAN) and dissolved Norman Landfill leachate fulvic acid, Suwannee River fulvic acid, Suwannee River humic acid, and Leonardite humic acid were examined as a function of pH, fulvic and humic acid (FA and HA) concentration, and solvent polarity using steady-state fluorescence spectroscopy. Static quenching processes, as indicated by linear Stern-Volmer plots and high K(d) values, were positively correlated with the % aromaticity of the FA and HAs, as well as with solution pH. Results illustrate that for FA molecules with relatively low % aromaticity values, solvophobic interactions between PRODAN and FA are the primary interaction mode. For HA molecules with higher % aromaticity, PRODAN engages in both solvophobic interactions and pi-pi interactions, in particular electron donor-acceptor interactions, via condensed aromatic, electron-accepting moieties inherent within HA molecules. Experiments modifying solvent polarity demonstrated that protonation of carboxylic acid functional groups at low pH ( approximately 4) increased the hydrophobicity of the dissolved FA and HA molecules, thereby enhancing noncovalent interactions with PRODAN through increased solvophobic forces. PMID:17632208

  20. Inherent Driving Force for Charge Separation in Curved Stacks of Oligothiophenes

    SciTech Connect

    Wu, Qin

    2015-01-30

    Coexistence of high local charge mobility and an energy gradient can lead to efficient free charge carrier generation from geminate charge transfer states at the donor–acceptor interface in bulk heterojunction organic photovoltaics. It is, however, not clear what polymer microstructures can support such coexistence. Using recent methods from density functional theory, we propose that a stack of similarly curved oligothiophene chains can deliver the requirements for efficient charge separation. Curved stacks are stable because of the polymer’s strong π-stacking ability and because backbone torsions are flexible in neutral chains. However, energy of a charge in a polymer chain has remarkably stronger dependence on torsions. The trend of increasing planarity in curved stacks effectively creates an energy gradient that drives charge in one direction. The curvature of these partially ordered stacks is found to beneficially interact with fullerenes for charge separation. The curved stacks, therefore, are identified as possible building blocks for interfacial structures that lead to efficient free carrier generation in high-performing organic photovoltaic systems.

  1. Inherent Driving Force for Charge Separation in Curved Stacks of Oligothiophenes

    DOE PAGESBeta

    Wu, Qin

    2015-01-30

    Coexistence of high local charge mobility and an energy gradient can lead to efficient free charge carrier generation from geminate charge transfer states at the donor–acceptor interface in bulk heterojunction organic photovoltaics. It is, however, not clear what polymer microstructures can support such coexistence. Using recent methods from density functional theory, we propose that a stack of similarly curved oligothiophene chains can deliver the requirements for efficient charge separation. Curved stacks are stable because of the polymer’s strong π-stacking ability and because backbone torsions are flexible in neutral chains. However, energy of a charge in a polymer chain has remarkablymore » stronger dependence on torsions. The trend of increasing planarity in curved stacks effectively creates an energy gradient that drives charge in one direction. The curvature of these partially ordered stacks is found to beneficially interact with fullerenes for charge separation. The curved stacks, therefore, are identified as possible building blocks for interfacial structures that lead to efficient free carrier generation in high-performing organic photovoltaic systems.« less

  2. Guanine base stacking in G-quadruplex nucleic acids.

    PubMed

    Lech, Christopher Jacques; Heddi, Brahim; Phan, Anh Tuân

    2013-02-01

    G-quadruplexes constitute a class of nucleic acid structures defined by stacked guanine tetrads (or G-tetrads) with guanine bases from neighboring tetrads stacking with one another within the G-tetrad core. Individual G-quadruplexes can also stack with one another at their G-tetrad interface leading to higher-order structures as observed in telomeric repeat-containing DNA and RNA. In this study, we investigate how guanine base stacking influences the stability of G-quadruplexes and their stacked higher-order structures. A structural survey of the Protein Data Bank is conducted to characterize experimentally observed guanine base stacking geometries within the core of G-quadruplexes and at the interface between stacked G-quadruplex structures. We couple this survey with a systematic computational examination of stacked G-tetrad energy landscapes using quantum mechanical computations. Energy calculations of stacked G-tetrads reveal large energy differences of up to 12 kcal/mol between experimentally observed geometries at the interface of stacked G-quadruplexes. Energy landscapes are also computed using an AMBER molecular mechanics description of stacking energy and are shown to agree quite well with quantum mechanical calculated landscapes. Molecular dynamics simulations provide a structural explanation for the experimentally observed preference of parallel G-quadruplexes to stack in a 5'-5' manner based on different accessible tetrad stacking modes at the stacking interfaces of 5'-5' and 3'-3' stacked G-quadruplexes. PMID:23268444

  3. TESTING FOR CPT VIOLATION IN Bstack">0stack">s SEMILEPTONIC DECAYS

    NASA Astrophysics Data System (ADS)

    Kooten, R. Van

    2014-01-01

    A DØ analysis measuring the charge asymmetry Astack">bstack">sl of like-sign dimuon events due to semileptonic b-hadron decays at the Fermilab Tevatron Collider has shown indications of possible anomalous CP violation in the mixing of neutral B mesons. This result has been used to extract the first senstivity to CPT violation in the Bstack">0stack">s system. An analysis to explore further this anomaly by specifically measuring the semileptonic charge asymmetry, astack">sstack">sl, in Bstack">0stack">s decays is described, as well as how a variant of this analysis can be used to explore a larger set of CPT-violating parameters in the Bstack">0stack">s system for the first time.

  4. Progress of MCFC stack technology at Toshiba

    SciTech Connect

    Hori, M.; Hayashi, T.; Shimizu, Y.

    1996-12-31

    Toshiba is working on the development of MCFC stack technology; improvement of cell characteristics, and establishment of separator technology. For the cell technology, Toshiba has concentrated on both the restraints of NiO cathode dissolution and electrolyte loss from cells, which are the critical issues to extend cell life in MCFC, and great progress has been made. On the other hand, recognizing that the separator is one of key elements in accomplishing reliable and cost-competitive MCFC stacks, Toshiba has been accelerating the technology establishment and verification of an advanced type separator. A sub-scale stack with such a separator was provided for an electric generating test, and has been operated for more than 10,000 hours. This paper presents several topics obtained through the technical activities in the MCFC field at Toshiba.

  5. Intelligent Control System of Stack-boiler

    NASA Astrophysics Data System (ADS)

    Jing, Li; Jingxia, Niu; Jianhua, Lang; Shaofeng, Li; Zhi, Li

    Boiler combustion control system's basic task is to make fuel burn calories adapt to the needs of the water temperature and ensure the economical combustion and the safe operation. In the foundations which have analyzed the stack-boiler's work process and control system structure, the system designed by using the self-learning and self-optimizing fuzzy control system of the PC to make air/coal ratio achieve the best and realize the optimized combustion; through PLC to accelerate the speed of response to the boiler, and speed up the PC to optimize the speed and realize the double loop control system for stack-boiler. The control system in premise of the stack-boiler reaches the goal of the load to achieve the highest efficiency of the boiler combustion.

  6. Radiation Tolerant Intelligent Memory Stack (RTIMS)

    NASA Technical Reports Server (NTRS)

    Ng, Tak-kwong; Herath, Jeffrey A.

    2006-01-01

    The Radiation Tolerant Intelligent Memory Stack (RTIMS), suitable for both geostationary and low earth orbit missions, has been developed. The memory module is fully functional and undergoing environmental and radiation characterization. A self-contained flight-like module is expected to be completed in 2006. RTIMS provides reconfigurable circuitry and 2 gigabits of error corrected or 1 gigabit of triple redundant digital memory in a small package. RTIMS utilizes circuit stacking of heterogeneous components and radiation shielding technologies. A reprogrammable field programmable gate array (FPGA), six synchronous dynamic random access memories, linear regulator, and the radiation mitigation circuitries are stacked into a module of 42.7mm x 42.7mm x 13.00mm. Triple module redundancy, current limiting, configuration scrubbing, and single event function interrupt detection are employed to mitigate radiation effects. The mitigation techniques significantly simplify system design. RTIMS is well suited for deployment in real-time data processing, reconfigurable computing, and memory intensive applications.

  7. Fuel cell stack monitoring and system control

    DOEpatents

    Keskula, Donald H.; Doan, Tien M.; Clingerman, Bruce J.

    2005-01-25

    A control method for monitoring a fuel cell stack in a fuel cell system in which the actual voltage and actual current from the fuel cell stack are monitored. A preestablished relationship between voltage and current over the operating range of the fuel cell is established. A variance value between the actual measured voltage and the expected voltage magnitude for a given actual measured current is calculated and compared with a predetermined allowable variance. An output is generated if the calculated variance value exceeds the predetermined variance. The predetermined voltage-current for the fuel cell is symbolized as a polarization curve at given operating conditions of the fuel cell. Other polarization curves may be generated and used for fuel cell stack monitoring based on different operating pressures, temperatures, hydrogen quantities.

  8. Color considerations in fluorescent solar concentrator stacks.

    PubMed

    Swift, Paul D; Smith, Geoff B

    2003-09-01

    We present modeled results of the luminous and color outputs of a three-layer stack of fluorescent planar concentrators (FPCs). FPCs have the potential to provide sufficient luminous output to illuminate moderate-sized rooms for reasonably-sized collecting areas. It is of course necessary not only that the lumens be sufficient, but also that the light be sufficiently white as to be comfortable. Modeling shows that by use of a stack of three FPCs, one each of violet, green, and red, it is possible to achieve good color rendering and sufficient lighting levels for room illumination. PMID:12962389

  9. Fuel cell stack monitoring and system control

    DOEpatents

    Keskula, Donald H.; Doan, Tien M.; Clingerman, Bruce J.

    2004-02-17

    A control method for monitoring a fuel cell stack in a fuel cell system in which the actual voltage and actual current from the fuel cell stack are monitored. A preestablished relationship between voltage and current over the operating range of the fuel cell is established. A variance value between the actual measured voltage and the expected voltage magnitude for a given actual measured current is calculated and compared with a predetermined allowable variance. An output is generated if the calculated variance value exceeds the predetermined variance. The predetermined voltage-current for the fuel cell is symbolized as a polarization curve at given operating conditions of the fuel cell.

  10. Three wafer stacking for 3D integration.

    SciTech Connect

    Greth, K. Douglas; Ford, Christine L.; Lantz, Jeffrey W.; Shinde, Subhash L.; Timon, Robert P.; Bauer, Todd M.; Hetherington, Dale Laird; Sanchez, Carlos Anthony

    2011-11-01

    Vertical wafer stacking will enable a wide variety of new system architectures by enabling the integration of dissimilar technologies in one small form factor package. With this LDRD, we explored the combination of processes and integration techniques required to achieve stacking of three or more layers. The specific topics that we investigated include design and layout of a reticle set for use as a process development vehicle, through silicon via formation, bonding media, wafer thinning, dielectric deposition for via isolation on the wafer backside, and pad formation.

  11. Harry Stack Sullivan Colloquium: George Herbert Mead and Harry Stack Sullivan: an unfinished synthesis.

    PubMed

    Cottrell, L S

    1978-05-01

    HOW DO YOU create a new self? However he may phrase this question, it is a central theoretical and practical concern of the therapist every time he confronts a client who comes to him for help. What are the processes out of which the human self emerges? However he may phrase the question, it is a central concern of the social psychologist. The obvious convergence of interests indicated by these two questions should occasion no surprise among students of Sullivan and Mead. What perhaps should be surprising is that an effective synthesis of their theories has progressed no further than it has to date. My remarks today are based on the conviction that a more adequate psychiatric theory and practice and a more complete social psychological theory and research program depend on such a synthesis. Behavioral scientists concerned with the development of a truly interactionist social psychology are, I believe, generally agreed that George Herbert Mead (1863-1931), philosopher and social psychologist, and Harry Stack Sullivan (1892-1949), psychiatrist and social psychologist, have laid conceptual foundations upon which such a discipline can be erected. Now a vast assortment of activities is tagged as social psychology and its boundaries are, indeed, difficult to draw. However, for our present purposes we can define its focus as the study of the processes and products of inter- and intrapersonal and inter- and intragoup interaction, let the boundaries fall where they will. PMID:349586

  12. Longitudinal ultrasonic vibration assisted guillotining of stacked paper.

    PubMed

    Deibel, Karl-Robert; Kaiser, Fabian; Zimmermann, Remo; Meier, Linus; Bolt, Peter; Wegener, Konrad

    2014-08-01

    Ultrasonic vibration assisted cutting is a complex process with high dynamics. The interaction between cutting tool and workpiece is of key interest to understand the entire process. Experimental investigations are limited by the dynamics of the measurement system, and thus appropriately modeling of the ultrasonic vibration assisted cutting process is essential. In this investigation, a dynamic model regarding the ultrasonic vibration assisted guillotining of stacked paper sheets is developed. A Kelvin-Voigt material model, representing the individual sheets, is chosen, with its stiffness and damping parameters being empirically determined. A novel measurement strategy for studying the contact time and interaction between cutting tool and workpiece is introduced. It allows the verification of the highly dynamic behavior of the developed model. With the dynamic model, the experimentally observed cutting forces can be calculated. It is found that the dynamic forces cause a quicker failure of the material, which leads to a lower compression of the stack prior to reaching the critical cutting force. PMID:24746507

  13. Stacking faults in a layered cobalt tellurium phosphate oxochloride

    NASA Astrophysics Data System (ADS)

    Zimmermann, Iwan; Johnsson, Mats

    2015-02-01

    The new compound Co2Te3(PO4)O6Cl was synthesized by chemical reactions in a sealed and evacuated silica tube. The crystal structure was solved from single crystal diffraction data and is made up by charge neutral layers. Within the layers two types of chains are made up by edge sharing [CoO6] and [CoO5Cl] polyhedra respectively. The chains are separated by tellurium oxide and phosphate building blocks. There are only weak Van der Waals interactions in between the layers and severe diffuse scattering is observed due to faulted stacking of the layers. Structure solutions in a P-1 triclinic cell and a larger monoclinic cell in P21/c are discussed and compared to a computer generated model. The reasons for the stacking faults may be due to that there are two positions available for each layer that results in similar connectivity to the next layer in addition to the relatively wide channels in between the layers that reduce the Van der Waals interactions in between them.

  14. Aromatic stacking between nucleobase and enzyme promotes phosphate ester hydrolysis in dUTPase

    PubMed Central

    Pecsi, Ildiko; Leveles, Ibolya; Harmat, Veronika; Vertessy, Beata G.; Toth, Judit

    2010-01-01

    Aromatic interactions are well-known players in molecular recognition but their catalytic role in biological systems is less documented. Here, we report that a conserved aromatic stacking interaction between dUTPase and its nucleotide substrate largely contributes to the stabilization of the associative type transition state of the nucleotide hydrolysis reaction. The effect of the aromatic stacking on catalysis is peculiar in that uracil, the aromatic moiety influenced by the aromatic interaction is relatively distant from the site of hydrolysis at the alpha-phosphate group. Using crystallographic, kinetics, optical spectroscopy and thermodynamics calculation approaches we delineate a possible mechanism by which rate acceleration is achieved through the remote π–π interaction. The abundance of similarly positioned aromatic interactions in various nucleotide hydrolyzing enzymes (e.g. most families of ATPases) raises the possibility of the reported phenomenon being a general component of the enzymatic catalysis of phosphate ester hydrolysis. PMID:20601405

  15. Aromatic stacking between nucleobase and enzyme promotes phosphate ester hydrolysis in dUTPase.

    PubMed

    Pecsi, Ildiko; Leveles, Ibolya; Harmat, Veronika; Vertessy, Beata G; Toth, Judit

    2010-11-01

    Aromatic interactions are well-known players in molecular recognition but their catalytic role in biological systems is less documented. Here, we report that a conserved aromatic stacking interaction between dUTPase and its nucleotide substrate largely contributes to the stabilization of the associative type transition state of the nucleotide hydrolysis reaction. The effect of the aromatic stacking on catalysis is peculiar in that uracil, the aromatic moiety influenced by the aromatic interaction is relatively distant from the site of hydrolysis at the alpha-phosphate group. Using crystallographic, kinetics, optical spectroscopy and thermodynamics calculation approaches we delineate a possible mechanism by which rate acceleration is achieved through the remote π-π interaction. The abundance of similarly positioned aromatic interactions in various nucleotide hydrolyzing enzymes (e.g. most families of ATPases) raises the possibility of the reported phenomenon being a general component of the enzymatic catalysis of phosphate ester hydrolysis. PMID:20601405

  16. Gapped phase in AA-stacked bilayer graphene

    NASA Astrophysics Data System (ADS)

    Brey, L.; Fertig, H. A.

    2013-03-01

    AA-stacked bilayer graphene supports Fermi circles in its bonding and antibonding bands, which coincide exactly, leading to symmetry breaking in the presence of electron-electron interactions. We analyze a continuum model of this system in the Hartree-Fock approximation, using a self-consistently screened interaction that accounts for the gap in the spectrum in the broken symmetry state. The order parameter in the ground state is shown to be of the Ising type, involving transfer of charge between the layers in opposite directions for different sublattices. We analyze the Ising phase transition for the system and argue that it continuously evolves into a Kosterlitz-Thouless transition in the limit of vanishing interlayer separation d. The transition temperature is shown to depend only on the effective spin stiffness of the system even for d>0, and an estimate of its value suggests that the transition temperature is of the order of a few degrees Kelvin.

  17. SRS reactor stack plume marking tests

    SciTech Connect

    Petry, S.F.

    1992-03-01

    Tests performed in 105-K in 1987 and 1988 demonstrated that the stack plume can successfully be made visible (i.e., marked) by introducing smoke into the stack breech. The ultimate objective of these tests is to provide a means during an emergency evacuation so that an evacuee can readily identify the stack plume and evacuate in the opposite direction, thus minimizing the potential of severe radiation exposure. The EPA has also requested DOE to arrange for more tests to settle a technical question involving the correct calculation of stack downwash. New test canisters were received in 1988 designed to produce more smoke per unit time; however, these canisters have not been evaluated, because normal ventilation conditions have not been reestablished in K Area. Meanwhile, both the authorization and procedure to conduct the tests have expired. The tests can be performed during normal reactor operation. It is recommended that appropriate authorization and procedure approval be obtained to resume testing after K Area restart.

  18. 40 CFR 61.53 - Stack sampling.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Mercury § 61.53 Stack sampling. (a) Mercury ore processing facility. (1) Unless a waiver of emission testing is obtained under § 61.13, each owner or operator processing mercury ore shall test emissions from the source...

  19. 40 CFR 61.53 - Stack sampling.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Mercury § 61.53 Stack sampling. (a) Mercury ore processing facility. (1) Unless a waiver of emission testing is obtained under § 61.13, each owner or operator processing mercury ore shall test emissions from the source...

  20. 40 CFR 61.53 - Stack sampling.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Mercury § 61.53 Stack sampling. (a) Mercury ore processing facility. (1) Unless a waiver of emission testing is obtained under § 61.13, each owner or operator processing mercury ore shall test emissions from the source...

  1. 40 CFR 61.53 - Stack sampling.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Mercury § 61.53 Stack sampling. (a) Mercury ore processing facility. (1) Unless a waiver of emission testing is obtained under § 61.13, each owner or operator processing mercury ore shall test emissions from the source...

  2. Stack Gas Scrubber Makes the Grade

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1975

    1975-01-01

    Describes a year long test of successful sulfur dioxide removal from stack gas with a calcium oxide slurry. Sludge disposal problems are discussed. Cost is estimated at 0.6 mill per kwh not including sludge removal. A flow diagram and equations are included. (GH)

  3. 49 CFR 178.606 - Stacking test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... calculated based on the specific gravity that will be marked on the packaging. The minimum height of the... between the platens at this time must be recorded as zero deformation. The force A to then be applied must... number of containers that, when stacked, reach a height of 3 meters. s = specific gravity of lading....

  4. 49 CFR 178.606 - Stacking test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... calculated based on the specific gravity that will be marked on the packaging. The minimum height of the... between the platens at this time must be recorded as zero deformation. The force A to then be applied must... number of containers that, when stacked, reach a height of 3 meters. s = specific gravity of lading....

  5. Venturis as silencers in a BOF stack

    SciTech Connect

    Kelsall, T.; Gerritsen, T.; Landon, T.

    1995-06-01

    Installation of a venture in a BOF stack reduced the sound level in a local community by 10 to 15 db. This application resulted in the development of a new type of fan silencer, called the modal silencer, having the inherent advantages of low pressure drop and less maintenance compared with conventional types.

  6. Revisiting Stacking Fault Energy of Steels

    NASA Astrophysics Data System (ADS)

    Das, Arpan

    2016-02-01

    The stacking fault energy plays an important role in the transition of deformation microstructure. This energy is strongly dependent on the concentration of alloying elements and the temperature under which the alloy is exposed. Extensive literature review has been carried out and investigated that there are inconsistencies in findings on the influence of alloying elements on stacking fault energy. This may be attributed to the differences in chemical compositions, inaccuracy in measurements, and the methodology applied for evaluating the stacking fault energy. In the present research, a Bayesian neural network model is created to correlate the complex relationship between the extent of stacking fault energy with its influencing parameters in different austenitic grade steels. The model has been applied to confirm that the predictions are reasonable in the context of metallurgical principles and other data published in the open literature. In addition, it has been possible to estimate the isolated influence of particular variables such as nickel concentration, which exactly cannot in practice be varied independently. This demonstrates the ability of the method to investigate a new phenomenon in cases where the information cannot be accessed experimentally.

  7. 40 CFR 61.53 - Stack sampling.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Mercury § 61.53 Stack sampling. (a) Mercury ore processing facility. (1) Unless a waiver of emission testing is obtained under § 61.13, each owner or operator processing mercury ore shall test emissions from the source...

  8. 49 CFR 178.606 - Stacking test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Testing of Non-bulk Packagings and Packages § 178.606 Stacking test. (a) General. All packaging design... samples are required for each different packaging. For periodic retesting of packagings constructed of... invalidate the results of the test. (c) Test method—(1) Design qualification testing. The test sample must...

  9. Explosive demolition of K East Reactor Stack

    SciTech Connect

    2010-07-26

    Using $420,000 in Recovery Act funds, the Department of Energy and contractor CH2M HILL Plateau Remediation Company topped off four months of preparations when they safely demolished the exhaust stack at the K East Reactor and equipment inside the reactor building on July 23, 2010.

  10. 49 CFR 178.980 - Stacking test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    .... (3) Rigid plastic Large Packagings which bear the stacking load must be subjected to the test for 28.... w = maximum weight of one empty container in pounds. s = specific gravity (liquids) or density... passing the test. (1) For metal or rigid plastic Large Packagings, there may be no permanent...

  11. Removing Sulphur Dioxide From Stack Gases

    ERIC Educational Resources Information Center

    Slack, A. V.

    1973-01-01

    Process types, process concepts, claims and counterclaims, cost factors, and the level of developed technology for sulfur dioxide control in stack gases are focused upon and evaluated. Wet and dry processes as well as recovery and throwaway processes are compared. (BL)

  12. 49 CFR 178.1055 - Stacking test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR PACKAGINGS Testing of Flexible Bulk... of all Flexible Bulk Containers design types. (b) Special preparation for the stacking test. All Flexible Bulk Containers design types must be loaded to their maximum permissible gross mass. (c)...

  13. Average Transmission Probability of a Random Stack

    ERIC Educational Resources Information Center

    Lu, Yin; Miniatura, Christian; Englert, Berthold-Georg

    2010-01-01

    The transmission through a stack of identical slabs that are separated by gaps with random widths is usually treated by calculating the average of the logarithm of the transmission probability. We show how to calculate the average of the transmission probability itself with the aid of a recurrence relation and derive analytical upper and lower…

  14. 30 CFR 77.302 - Bypass stacks.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Bypass stacks. 77.302 Section 77.302 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Thermal Dryers §...

  15. 30 CFR 77.302 - Bypass stacks.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Bypass stacks. 77.302 Section 77.302 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Thermal Dryers §...

  16. 30 CFR 77.302 - Bypass stacks.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Bypass stacks. 77.302 Section 77.302 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Thermal Dryers §...

  17. 30 CFR 77.302 - Bypass stacks.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Bypass stacks. 77.302 Section 77.302 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Thermal Dryers §...

  18. 30 CFR 77.302 - Bypass stacks.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Bypass stacks. 77.302 Section 77.302 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Thermal Dryers §...

  19. Explosive demolition of K East Reactor Stack

    ScienceCinema

    None

    2010-09-02

    Using $420,000 in Recovery Act funds, the Department of Energy and contractor CH2M HILL Plateau Remediation Company topped off four months of preparations when they safely demolished the exhaust stack at the K East Reactor and equipment inside the reactor building on July 23, 2010.

  20. Stacks in canonical RNA pseudoknot structures.

    PubMed

    Han, Hillary S W; Reidys, Christian M

    2009-05-01

    In this paper we study the distribution of stacks/loops in k-non-crossing, tau-canonical RNA pseudoknot structures (k,tau-structures). Here, an RNA structure is called k-non-crossing if it has no more than k-1 mutually crossing arcs and tau-canonical if each arc is contained in a stack of length at least tau. Based on the ordinary generating function of k,tau-structures [G. Ma, C.M. Reidys, Canonical RNA pseudoknot structures, J. Comput. Biol. 15 (10) (2008) 1257] we derive the bivariate generating function T(k, tau)(x, u) = Sigma(n>or=0)Sigma(0stacks and study its singularities. We show that for a specific parametrization of the variable u, T(k, tau)(x, u) exhibits a unique, dominant singularity. The particular shift of this singularity parametrized by u implies a central limit theorem for the distribution of stack-numbers. Our results are of importance for understanding the 'language' of minimum-free energy RNA pseudoknot structures, generated by computer folding algorithms. PMID:19402214

  1. Stacking fault and twinning in nanocrystalline metals.

    SciTech Connect

    Liao, Xiaozhou; Zhao, Y.; Srivilliputhur, S. G.; Zhou, F.; Lavernia, E. J.; Baskes, M. I.; Zhu, Y. T.; Xu, H. F.

    2004-01-01

    Nanocrystalline Al processed by cryogenic ball-milling and nanocrystalline Cu processed by high-pressure torsion at a very low strain rate and at room temperature were investigated using high-resolution transmission electron microscopy. For nanocrystalline Al, we observed partial dislocation emission from grain boundaries, which consequently resulted in deformation stacking faults and twinning. We also observed deformation twins formed via two other mechanisms recently predicted by molecular dynamic simulations. These results are surprising because (1) partial dislocation emission from grain boundaries has not been experimentally observed although it has been predicted by simulations and (2) deformation stacking faults and twinning have not been reported in Al due to its high stacking fault energy. For nanocrystalline Cu, we found that twinning becomes a major deformation mechanism, which contrasts with the literature reports that deformation twinning in coarse-grained Cu occurs only under high strain rate and/or low temperature conditions and that reducing grain sizes suppresses deformation twinning. The investigation of the twinning morphology suggests that twins and stacking faults in nanocrystalline Cu were formed through partial dislocation emissions from grain boundaries. This mechanism differs from the pole mechanism operating in coarse-grained Cu.

  2. Stacked Deck: An Effective, School-Based Program for the Prevention of Problem Gambling

    ERIC Educational Resources Information Center

    Williams, Robert J.; Wood, Robert T.; Currie, Shawn R.

    2010-01-01

    School-based prevention programs are an important component of problem gambling prevention, but empirically effective programs are lacking. Stacked Deck is a set of 5-6 interactive lessons that teach about the history of gambling; the true odds and "house edge"; gambling fallacies; signs, risk factors, and causes of problem gambling; and skills…

  3. Measurement of heat conduction through stacked screens

    NASA Technical Reports Server (NTRS)

    Lewis, M. A.; Kuriyama, T.; Kuriyama, F.; Radebaugh, R.

    1998-01-01

    This paper describes the experimental apparatus for the measurement of heat conduction through stacked screens as well as some experimental results taken with the apparatus. Screens are stacked in a fiberglass-epoxy cylinder, which is 24.4 mm in diameter and 55 mm in length. The cold end of the stacked screens is cooled by a Gifford-McMahon (GM) cryocooler at cryogenic temperature, and the hot end is maintained at room temperature. Heat conduction through the screens is determined from the temperature gradient in a calibrated heat flow sensor mounted between the cold end of the stacked screens and the GM cryocooler. The samples used for these experiments consisted of 400-mesh stainless steel screens, 400-mesh phosphor bronze screens, and two different porosities of 325-mesh stainless steel screens. The wire diameter of the 400-mesh stainless steel and phosphor bronze screens was 25.4 micrometers and the 325-mesh stainless steel screen wire diameters were 22.9 micrometers and 27.9 micrometers. Standard porosity values were used for the experimental data with additional porosity values used on selected experiments. The experimental results showed that the helium gas between each screen enhanced the heat conduction through the stacked screens by several orders of magnitude compared to that in vacuum. The conduction degradation factor is the ratio of actual heat conduction to the heat conduction where the regenerator material is assumed to be a solid rod of the same cross sectional area as the metal fraction of the screen. This factor was about 0.1 for the stainless steel and 0.022 for the phosphor bronze, and almost constant for the temperature range of 40 to 80 K at the cold end.

  4. Antiproton stacking and un-stacking in the Fermilab Recycler Ring

    SciTech Connect

    Chandra Bhat

    2003-06-12

    The Fermilab Recycler Ring (RR) is intended to be used as a future antiproton storage ring for the Run II proton-antiproton collider operation. It is proposed that about 40mA of antiproton beam from the Accumulator Ring will be transferred to the Recycler once for every two to three hours, stacked and cooled. This operation continues for about 10 to 20 hours depending on the collider needs for antiprotons. Eventually, the cooled antiproton beam will be un-stacked from the Recycler and transferred to the Tevatron via the Main Injector. They have simulated stacking and un-stacking of antiprotons in the Recycler using multi-particle beam dynamics simulation code ESME. In this paper they present results of these simulations.

  5. A feature-based approach to modeling protein-protein interaction hot spots.

    PubMed

    Cho, Kyu-il; Kim, Dongsup; Lee, Doheon

    2009-05-01

    Identifying features that effectively represent the energetic contribution of an individual interface residue to the interactions between proteins remains problematic. Here, we present several new features and show that they are more effective than conventional features. By combining the proposed features with conventional features, we develop a predictive model for interaction hot spots. Initially, 54 multifaceted features, composed of different levels of information including structure, sequence and molecular interaction information, are quantified. Then, to identify the best subset of features for predicting hot spots, feature selection is performed using a decision tree. Based on the selected features, a predictive model for hot spots is created using support vector machine (SVM) and tested on an independent test set. Our model shows better overall predictive accuracy than previous methods such as the alanine scanning methods Robetta and FOLDEF, and the knowledge-based method KFC. Subsequent analysis yields several findings about hot spots. As expected, hot spots have a larger relative surface area burial and are more hydrophobic than other residues. Unexpectedly, however, residue conservation displays a rather complicated tendency depending on the types of protein complexes, indicating that this feature is not good for identifying hot spots. Of the selected features, the weighted atomic packing density, relative surface area burial and weighted hydrophobicity are the top 3, with the weighted atomic packing density proving to be the most effective feature for predicting hot spots. Notably, we find that hot spots are closely related to pi-related interactions, especially pi . . . pi interactions. PMID:19273533

  6. VIEW OF STACK WITH AUTOMOBILE AND TRACTOR REPAIR SHOP TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF STACK WITH AUTOMOBILE AND TRACTOR REPAIR SHOP TO THE FAR RIGHT. WAREHOUSE WITH ITS RIDGELINE ROTARY VENTS TO RIGHT OF STACK. VIEW FROM THE WEST - Kekaha Sugar Company, Sugar Mill Building, 8315 Kekaha Road, Kekaha, Kauai County, HI

  7. Project W-420 Stack Monitoring system upgrades conceptual design report

    SciTech Connect

    TUCK, J.A.

    1998-11-06

    This document describes the scope, justification, conceptual design, and performance of Project W-420 stack monitoring system upgrades on six NESHAP-designated, Hanford Tank Farms ventilation exhaust stacks.

  8. IET. Exhaust stack foundation under construction. Reinforced concrete footings for ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    IET. Exhaust stack foundation under construction. Reinforced concrete footings for duct at right of stack. Foundation is in octagonal shape. Date: October 29, 1954. INEEL negative no. 12711 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

  9. Stacking Sequence and Layer-Type Changes in Topologically Close-Packed Structures.

    NASA Astrophysics Data System (ADS)

    Pei, Shiyou

    1988-12-01

    Crystal structure changes in several A _3B-type quasi-binary alloy series, involving Fe, Co, Ni, Cu, Pd and Pt as the A-component elements and Ti, V, Zr and Nb as the B-component elements, have been explored experimentally using X-ray and electron diffraction. The aim of this work was to discover various stacking sequence and ordered layer-type changes in close-packed structures. Our experimental data further confirm that the hexagonality of the stacking always increases in these alloy series as either the electron concentration (e/a) of a given alloy, or the size ratio (R_{rm B} /R_{rm A}) between two types of atoms is increased. This trend is consistent with the results observed by earlier workers in similar alloy systems. Interestingly, we also note that these observed trends are independent of the component, either the A- or B-, and of the type of stacking layers, either the triangularly-ordered (T-type) or the rectangularly -ordered (R-type), involved in the substitutional change. In addition, two new paths of stacking sequence changes have been established through our experimental work, namely, 3 to 3 to 2 and 1 to 5 to 2. An Ising model has been explored to discover if the observed stacking sequence changes can be interpreted in terms of interactions between a few adjacent layers. Using these interactions as phenomenological parameters, a stacking stability map was constructed showing the arrangement of predicted ground state phases on a two-dimensional parameter -plane. Comparing this map with the known experimental data, it was found that the position and the extent of phase regions in the derived map are rather similar to several real composition phase diagrams. Therefore, such a map can provide useful information about the stacking sequence changes (e.g., allowed or excluded stacking arrangements for the neighboring phases) to be expected in an actual alloy phase diagrams. In a different approach, a total energy calculation utilizing the linearized

  10. Characterization of stacked-crystal PET detector designs for measurement of both TOF and DOI

    NASA Astrophysics Data System (ADS)

    Schmall, Jeffrey P.; Surti, Suleman; Karp, Joel S.

    2015-05-01

    A PET detector with good timing resolution and two-level depth-of-interaction (DOI) discrimination can be constructed using a single-ended readout of scintillator stacks of Lanthanum Bromide (LaBr3), with various Cerium dopant concentrations, including pure Cerium Bromide (CeBr3). The stacked crystal geometry creates a unique signal shape for interactions occurring in each layer, which can be used to identify the DOI, while retaining the inherently good timing properties of LaBr3 and CeBr3. In this work, single pixel elements are used to optimize the choice of scintillator, coupling of layers, and type of photodetector, evaluating the performance using a fast, single-channel photomultiplier tube (PMT) and a single 4 × 4 mm2 silicon photomultiplier (SiPM). We also introduce a method to quantify and evaluate the DOI discrimination accuracy. From signal shape measurements using fast waveform sampling, we found that in addition to differences in signal rise times, between crystal layers, there were also differences in the signal fall times. A DOI accuracy of 98% was achieved using our classification method for a stacked crystal pair, consisting of a 15 mm long LaBr3(Ce:20%) crystal on top of a 15 mm long CeBr3 crystal, readout using a PMT. A DOI accuracy of 95% was measured with a stack of two, identical, 12 mm long, CeBr3 crystals. The DOI accuracy of this crystal pair was reduced to 91% when using a SiPM for readout. For the stack of two, 12 mm long, CeBr3 crystals, a coincidence timing resolution (average of timing results from the top and bottom layer) of 199 ps was measured using a PMT, and this was improved to 153 ps when using a SiPM. These results show that with stacked LaBr3/CeBr3 scintillators and fast waveform sampling nearly perfect DOI accuracy can be achieved with excellent timing resolution—timing resolution that is only minimally degraded compared to results from a single CeBr3 crystal of comparable length to the stacked crystals. The

  11. Characterization of stacked-crystal PET detector designs for measurement of both TOF and DOI.

    PubMed

    Schmall, Jeffrey P; Surti, Suleman; Karp, Joel S

    2015-05-01

    A PET detector with good timing resolution and two-level depth-of-interaction (DOI) discrimination can be constructed using a single-ended readout of scintillator stacks of Lanthanum Bromide (LaBr3), with various Cerium dopant concentrations, including pure Cerium Bromide (CeBr3). The stacked crystal geometry creates a unique signal shape for interactions occurring in each layer, which can be used to identify the DOI, while retaining the inherently good timing properties of LaBr3 and CeBr3. In this work, single pixel elements are used to optimize the choice of scintillator, coupling of layers, and type of photodetector, evaluating the performance using a fast, single-channel photomultiplier tube (PMT) and a single 4 × 4 mm(2) silicon photomultiplier (SiPM). We also introduce a method to quantify and evaluate the DOI discrimination accuracy. From signal shape measurements using fast waveform sampling, we found that in addition to differences in signal rise times, between crystal layers, there were also differences in the signal fall times. A DOI accuracy of 98% was achieved using our classification method for a stacked crystal pair, consisting of a 15 mm long LaBr3(Ce:20%) crystal on top of a 15 mm long CeBr3 crystal, readout using a PMT. A DOI accuracy of 95% was measured with a stack of two, identical, 12 mm long, CeBr3 crystals. The DOI accuracy of this crystal pair was reduced to 91% when using a SiPM for readout. For the stack of two, 12 mm long, CeBr3 crystals, a coincidence timing resolution (average of timing results from the top and bottom layer) of 199 ps was measured using a PMT, and this was improved to 153 ps when using a SiPM. These results show that with stacked LaBr3/CeBr3 scintillators and fast waveform sampling nearly perfect DOI accuracy can be achieved with excellent timing resolution-timing resolution that is only minimally degraded compared to results from a single CeBr3 crystal of comparable length to the stacked crystals. The

  12. Characterization of stacked-crystal PET detector designs for measurement of both TOF and DOI

    PubMed Central

    Schmall, Jeffrey P; Surti, Suleman; Karp, Joel S

    2015-01-01

    A PET detector with good timing resolution and two-level depth-of-interaction (DOI) discrimination can be constructed using a single-ended readout of scintillator stacks of Lanthanum Bromide (LaBr3), with various Cerium dopant concentrations, including pure Cerium Bromide (CeBr3). The stacked crystal geometry creates a unique signal shape for interactions occurring in each layer, which can be used to identify the DOI, while retaining the inherently good timing properties of LaBr3 and CeBr3. In this work, single pixel elements are used to optimize the choice of scintillator, coupling of layers, and type of photodetector, evaluating the performance using a fast, single-channel photomultiplier tube (PMT) and a single 4×4 mm2 silicon photomultiplier (SiPM). We also introduce a method to quantify and evaluate the DOI discrimination accuracy. From signal shape measurements using fast waveform sampling, we found that in addition to differences in signal rise times, between crystal layers, there were also differences in the signal fall times. A DOI accuracy of 98% was achieved using our classification method for a stacked crystal pair, consisting of a 15-mm long LaBr3(Ce:20%) crystal on top of a 15-mm long CeBr3 crystal, readout using a PMT. A DOI accuracy of 95% was measured with a stack of two, identical, 12-mm long, CeBr3 crystals. The DOI accuracy of this crystal pair was reduced to 91% when using a SiPM for readout. For the stack of two, 12-mm long, CeBr3 crystals, a coincidence timing resolution (average of timing results from the top and bottom layer) of 199 ps was measured using a PMT, and this was improved to 153 ps when using a SiPM. These results show that with stacked LaBr3/CeBr3 scintillators and fast waveform sampling nearly perfect DOI accuracy can be achieved with excellent timing resolution—timing resolution that is only minimally degraded compared to results from a single CeBr3 crystal of comparable length to the stacked crystals. The interface in the

  13. Seismic upgrade design for an exhaust stack building

    SciTech Connect

    Maryak, M.E. ); Malik, L.E. )

    1991-01-01

    An exhaust stack building of a nuclear reactor facility with complex structural configuration has been analyzed and evaluated and retrofitted for seismic forces. The building was built in the 1950's and had not been designed to resist seismic forces. A rigorous analysis and evaluation program was implemented to minimize costly retrofits required to upgrade the building to resist high seismic forces. Seismic evaluations were performed for the building in its as-is configuration, and as modified for several upgrade schemes. Soil-structure-interaction, basemat flexibility and the influence of the nearby reactor building were considered in rigorous seismic analyses. These analyses and evaluations enabled limited upgrades to qualify the stack building for the seismic forces. Some of the major conclusions of this study are: a phased approach of seismic analyses, utilizing simplified models to evaluate practicable upgrade schemes, and, then incorporating the most suitable scheme in a rigorous model to obtain design forces for upgrades, is an efficient and cost- effective approach for seismic qualification of nuclear facilities to higher seismic criteria; and finalizing the upgrade of a major nuclear facility is an iterative process, which continues throughout the construction of the upgrades.

  14. Seismic upgrade design for an exhaust stack building

    SciTech Connect

    Maryak, M.E.; Malik, L.E.

    1991-12-31

    An exhaust stack building of a nuclear reactor facility with complex structural configuration has been analyzed and evaluated and retrofitted for seismic forces. The building was built in the 1950`s and had not been designed to resist seismic forces. A rigorous analysis and evaluation program was implemented to minimize costly retrofits required to upgrade the building to resist high seismic forces. Seismic evaluations were performed for the building in its as-is configuration, and as modified for several upgrade schemes. Soil-structure-interaction, basemat flexibility and the influence of the nearby reactor building were considered in rigorous seismic analyses. These analyses and evaluations enabled limited upgrades to qualify the stack building for the seismic forces. Some of the major conclusions of this study are: a phased approach of seismic analyses, utilizing simplified models to evaluate practicable upgrade schemes, and, then incorporating the most suitable scheme in a rigorous model to obtain design forces for upgrades, is an efficient and cost- effective approach for seismic qualification of nuclear facilities to higher seismic criteria; and finalizing the upgrade of a major nuclear facility is an iterative process, which continues throughout the construction of the upgrades.

  15. Stacked Polymer nanofiber array for high-performance supercapacitors

    NASA Astrophysics Data System (ADS)

    Wang, Shiren; Qiu, Jenny

    2015-03-01

    The vertically aligned polyaniline (PANI) nanowires arrays and monolayer graphene sheets were layer-by-layered deposited to specific substrate for tailored structures. Driven by external voltage, aniline molecules and graphene oxide were alternatively assembled for hierarchical porous three-dimensional nanostructures while graphene oxide was in-situ reduced to graphene during the assembly process. As-produced stacked arrays were used as the electrodes of an ultra-capacitor, and an unusual electrochemical behavior was discovered. The capacitance increases as the stack of nanowire arrays increases, resulting in high energy density and high power density at same time. Further analysis found that the distinctive electrochemical behavior originates from the electrode/electrolyte interactions and the dependence on the diffusion and charge transferring process. The specific energy density was as high as 137 Wh/Kg while power density is in excess of 2000 W/Kg. This work pointed a simple pathway to tailor polymer structure and electrochemistry for robust design of high-performance ultra-capacitor at a limited lateral size. National Science Foundation.

  16. Evaluation of a stack: A concrete chimney with brick liner

    SciTech Connect

    Joshi, J.R.; Amin, J.A.; Porthouse, R.A.

    1995-12-31

    A 200 ft. tall stack, consisting of a concrete chimney with an independent acid proof brick liner built in the 1950`s, serving the Separations facility at the Savannah River Site (SRS), was evaluated for the performance category 3 (PC3) level of Natural Phenomena Hazards (NPH) effects. The inelastic energy absorption capacity of the concrete chimney was considered in the evaluation of the earthquake resistance, in particular, to compute the F{sub {mu}} factor. The calculated value of F{sub {mu}} exceeded 3.0, while the seismic demand for the PC3 level, using an F{sub {mu}} value of 1.5, was found to be less than the capacity of the concrete chimney. The capacity formulation of ACI 307 was modified to incorporate the effect of an after design opening on the tension side. There are considerable uncertainties in determining the earthquake resistance of the independent brick liner. The critical liner section, located at the bottom of the breeching opening, does not meet the current recommendations. A discussion is provided for the possible acceptable values for the ``Moment Reduction Factor``, R{sub w} or F{sub {mu}} for the liner. Comments are provided on the comparison of stack demands using response spectra (RS) versus time history (TH) analysis, with and without soil structure interaction (SSI) effects.

  17. Space plasma physics: isotopic stack: measurement of heavy cosmic rays.

    PubMed

    Beaujean, R; Schmidt, M; Enge, W; Siegmon, G; Krause, J; Fischer, E

    1984-07-13

    A stack of plastic nuclear track detectors was exposed to heavy cosmic rays on the pallet of Spacelab 1. Some layers of the stack were rotated with respect to the main stack to determine the arrival time of the particles. After return of the stack the latent particle tracks are revealed by chemical etching. Under the optical microscope the charge, mass, energy, and impact direction of the particles can be deduced from the track geometry. PMID:17837938

  18. Wideband analytical equivalent circuit for one-dimensional periodic stacked arrays.

    PubMed

    Molero, Carlos; Rodríguez-Berral, Raúl; Mesa, Francisco; Medina, Francisco; Yakovlev, Alexander B

    2016-01-01

    A wideband equivalent circuit is proposed for the accurate analysis of scattering from a set of stacked slit gratings illuminated by a plane wave with transverse magnetic or electric polarization that impinges normally or obliquely along one of the principal planes of the structure. The slit gratings are printed on dielectric slabs of arbitrary thickness, including the case of closely spaced gratings that interact by higher-order modes. A Π-circuit topology is obtained for a pair of coupled arrays, with fully analytical expressions for all the circuit elements. This equivalent Π circuit is employed as the basis to derive the equivalent circuit of finite stacks with any given number of gratings. Analytical expressions for the Brillouin diagram and the Bloch impedance are also obtained for infinite periodic stacks. PMID:26871189

  19. Entropy and biological systems: Experimentally-investigated entropy-driven stacking of plant photosynthetic membranes

    NASA Astrophysics Data System (ADS)

    Jia, Husen; Liggins, John R.; Chow, Wah Soon

    2014-02-01

    According to the Second Law of Thermodynamics, an overall increase of entropy contributes to the driving force for any physicochemical process, but entropy has seldom been investigated in biological systems. Here, for the first time, we apply Isothermal Titration Calorimetry (ITC) to investigate the Mg2+-induced spontaneous stacking of photosynthetic membranes isolated from spinach leaves. After subtracting a large endothermic interaction of MgCl2 with membranes, unrelated to stacking, we demonstrate that the enthalpy change (heat change at constant pressure) is zero or marginally positive or negative. This first direct experimental evidence strongly suggests that an entropy increase significantly drives membrane stacking in this ordered biological structure. Possible mechanisms for the entropy increase include: (i) the attraction between discrete oppositely-charged areas, releasing counterions; (ii) the release of loosely-bound water molecules from the inter-membrane gap; (iii) the increased orientational freedom of previously-aligned water dipoles; and (iv) the lateral rearrangement of membrane components.

  20. Process for 3D chip stacking

    DOEpatents

    Malba, Vincent

    1998-01-01

    A manufacturable process for fabricating electrical interconnects which extend from a top surface of an integrated circuit chip to a sidewall of the chip using laser pantography to pattern three dimensional interconnects. The electrical interconnects may be of an L-connect or L-shaped type. The process implements three dimensional (3D) stacking by moving the conventional bond or interface pads on a chip to the sidewall of the chip. Implementation of the process includes: 1) holding individual chips for batch processing, 2) depositing a dielectric passivation layer on the top and sidewalls of the chips, 3) opening vias in the dielectric, 4) forming the interconnects by laser pantography, and 5) removing the chips from the holding means. The process enables low cost manufacturing of chips with bond pads on the sidewalls, which enables stacking for increased performance, reduced space, and higher functional per unit volume.

  1. Process for 3D chip stacking

    DOEpatents

    Malba, V.

    1998-11-10

    A manufacturable process for fabricating electrical interconnects which extend from a top surface of an integrated circuit chip to a sidewall of the chip using laser pantography to pattern three dimensional interconnects. The electrical interconnects may be of an L-connect or L-shaped type. The process implements three dimensional (3D) stacking by moving the conventional bond or interface pads on a chip to the sidewall of the chip. Implementation of the process includes: (1) holding individual chips for batch processing, (2) depositing a dielectric passivation layer on the top and sidewalls of the chips, (3) opening vias in the dielectric, (4) forming the interconnects by laser pantography, and (5) removing the chips from the holding means. The process enables low cost manufacturing of chips with bond pads on the sidewalls, which enables stacking for increased performance, reduced space, and higher functional per unit volume. 3 figs.

  2. Development of on-site PAFC stacks

    SciTech Connect

    Hotta, K.; Matsumoto, Y.; Horiuchi, H.; Ohtani, T.

    1996-12-31

    PAFC (Phosphoric Acid Fuel Cell) has been researched for commercial use and demonstration plants have been installed in various sites. However, PAFC don`t have a enough stability yet, so more research and development must be required in the future. Especially, cell stack needs a proper state of three phases (liquid, gas and solid) interface. It is very difficult technology to keep this condition for a long time. In the small size cell with the electrode area of 100 cm{sup 2}, gas flow and temperature distributions show uniformity. But in the large size cell with the electrode area of 4000 cm{sup 2}, the temperature distributions show non-uniformity. These distributions would cause to be shorten the cell life. Because these distributions make hot-spot and gas poverty in limited parts. So we inserted thermocouples in short-stack for measuring three-dimensional temperature distributions and observed effects of current density and gas utilization on temperature.

  3. SOFC cells and stacks for complex fuels

    SciTech Connect

    Edward M. Sabolsky; Matthew Seabaugh; Katarzyna Sabolsky; Sergio A. Ibanez; Zhimin Zhong

    2007-07-01

    Reformed hydrocarbon and coal (syngas) fuels present an opportunity to integrate solid oxide fuel cells into the existing fuel infrastructure. However, these fuels often contain impurities or additives that may lead to cell degradation through sulfur poisoning or coking. Achieving high performance and sulfur tolerance in SOFCs operating on these fuels would simplify system balance of plant and sequestration of anode tail gas. NexTech Materials, Ltd., has developed a suite of materials and components (cells, seals, interconnects) designed for operation in sulfur-containing syngas fuels. These materials and component technologies have been integrated into an SOFC stack for testing on simulated propane, logistic fuel reformates and coal syngas. Details of the technical approach, cell and stack performance is reported.

  4. System for inspection of stacked cargo containers

    SciTech Connect

    Derenzo, Stephen

    2011-08-16

    The present invention relates to a system for inspection of stacked cargo containers. One embodiment of the invention generally comprises a plurality of stacked cargo containers arranged in rows or tiers, each container having a top, a bottom a first side, a second side, a front end, and a back end; a plurality of spacers arranged in rows or tiers; one or more mobile inspection devices for inspecting the cargo containers, wherein the one or more inspection devices are removeably disposed within the spacers, the inspection means configured to move through the spacers to detect radiation within the containers. The invented system can also be configured to inspect the cargo containers for a variety of other potentially hazardous materials including but not limited to explosive and chemical threats.

  5. Radiation-Tolerant Intelligent Memory Stack - RTIMS

    NASA Technical Reports Server (NTRS)

    Ng, Tak-kwong; Herath, Jeffrey A.

    2011-01-01

    This innovation provides reconfigurable circuitry and 2-Gb of error-corrected or 1-Gb of triple-redundant digital memory in a small package. RTIMS uses circuit stacking of heterogeneous components and radiation shielding technologies. A reprogrammable field-programmable gate array (FPGA), six synchronous dynamic random access memories, linear regulator, and the radiation mitigation circuits are stacked into a module of 42.7 42.7 13 mm. Triple module redundancy, current limiting, configuration scrubbing, and single- event function interrupt detection are employed to mitigate radiation effects. The novel self-scrubbing and single event functional interrupt (SEFI) detection allows a relatively soft FPGA to become radiation tolerant without external scrubbing and monitoring hardware

  6. Multistage Force Amplification of Piezoelectric Stacks

    NASA Technical Reports Server (NTRS)

    Xu, Tian-Bing (Inventor); Siochi, Emilie J. (Inventor); Zuo, Lei (Inventor); Jiang, Xiaoning (Inventor); Kang, Jin Ho (Inventor)

    2015-01-01

    Embodiments of the disclosure include an apparatus and methods for using a piezoelectric device, that includes an outer flextensional casing, a first cell and a last cell serially coupled to each other and coupled to the outer flextensional casing such that each cell having a flextensional cell structure and each cell receives an input force and provides an output force that is amplified based on the input force. The apparatus further includes a piezoelectric stack coupled to each cell such that the piezoelectric stack of each cell provides piezoelectric energy based on the output force for each cell. Further, the last cell receives an input force that is the output force from the first cell and the last cell provides an output apparatus force In addition, the piezoelectric energy harvested is based on the output apparatus force. Moreover, the apparatus provides displacement based on the output apparatus force.

  7. Graphanes: Sheets and stacking under pressure

    SciTech Connect

    Wen, Xiao-Dong; Hand, Louis; Labet, Vanessa; Yang, Tao; Hoffmann, Roald; Ashcroft, N. W.; Oganov, Artem R.; Lyakhov, Andriy O.

    2011-04-26

    Eight isomeric two-dimensional graphane sheets are found in a theoretical study. Four of these nets—two built on chair cyclohexanes, two on boat—are more stable thermodynamically than the isomeric benzene, or polyacetylene. Three-dimensional crystals are built up from the two-dimensional sheets, and their hypothetical behavior under pressure (up to 300 GPa) is explored. While the three-dimensional graphanes remain, as expected, insulating or semiconducting in this pressure range, there is a remarkable inversion in stability of the five crystals studied. Two stacking polytypes that are not the most stable at ambient pressure (one based on an unusual chair cyclohexane net, the other on a boat) are significantly stabilized with increasing pressure relative to stackings of simple chair sheets. The explanation may lie in the balance on intra and intersheet contacts in the extended arrays.

  8. Learning algorithms for stack filter classifiers

    SciTech Connect

    Porter, Reid B; Hush, Don; Zimmer, Beate G

    2009-01-01

    Stack Filters define a large class of increasing filter that is used widely in image and signal processing. The motivations for using an increasing filter instead of an unconstrained filter have been described as: (1) fast and efficient implementation, (2) the relationship to mathematical morphology and (3) more precise estimation with finite sample data. This last motivation is related to methods developed in machine learning and the relationship was explored in an earlier paper. In this paper we investigate this relationship by applying Stack Filters directly to classification problems. This provides a new perspective on how monotonicity constraints can help control estimation and approximation errors, and also suggests several new learning algorithms for Boolean function classifiers when they are applied to real-valued inputs.

  9. Biofilters remove VOCs from stack gases

    SciTech Connect

    Not Available

    1993-10-01

    Weyerhaeuser's strandboard plant in Grayling, Mich., is using biofiltration to remove volatile organic compounds (VOCs) at the site. Primary constituents in the Weyerhaeuser stack gases are alcohols, aldehydes, organic acids, benzene and toluene. The alternative to biofiltration is incineration, but because the concentration of VOCs in the stack gases is so dilute, natural gas would be required. Incineration would be costly, and could introduce pollution problems by generating excess carbon dioxide (CO[sub 2]) and possibly nitrogen oxides. Two pilot biofilters, each about 20ft by 100ft in area, with 4-ft thick media of bark and ground trim ends, are using naturally occurring bacteria to destroy VOCs emanating from a wood panel press and a wood flake dryer. The press offgas biofilter, activated February 1993, had risen to 93% efficiency in removing VOCs by mid-May. The flake dryer exhaust biofilter, placed in service in April, already was more than 80% efficient.

  10. Annular feed air breathing fuel cell stack

    DOEpatents

    Wilson, Mahlon S.

    1996-01-01

    A stack of polymer electrolyte fuel cells is formed from a plurality of unit cells where each unit cell includes fuel cell components defining a periphery and distributed along a common axis, where the fuel cell components include a polymer electrolyte membrane, an anode and a cathode contacting opposite sides of the membrane, and fuel and oxygen flow fields contacting the anode and the cathode, respectively, wherein the components define an annular region therethrough along the axis. A fuel distribution manifold within the annular region is connected to deliver fuel to the fuel flow field in each of the unit cells. In a particular embodiment, a single bolt through the annular region clamps the unit cells together. In another embodiment, separator plates between individual unit cells have an extended radial dimension to function as cooling fins for maintaining the operating temperature of the fuel cell stack.

  11. Adjustable cutting guide aligns and positions stacks of material

    NASA Technical Reports Server (NTRS)

    Thiel, A. M.

    1966-01-01

    Adjustable guide tool aligns and positions stacks of material for cutting at various angles. The device adapts its shape to stacks of any corner angle, adjusts to any cutting angle, and quickly aligns the stacks for repeated cutting. With this device, an operator need not place his hands under the knife during alignment.

  12. 40 CFR 52.345 - Stack height regulations.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Stack height regulations. 52.345... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Colorado § 52.345 Stack height regulations. The State of Colorado has committed to revise its stack height regulations should EPA complete rulemaking...

  13. 40 CFR 52.1388 - Stack height regulations.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Stack height regulations. 52.1388... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Montana § 52.1388 Stack height regulations. The State of Montana has committed to revise its stack height regulations should EPA...

  14. 40 CFR 52.2633 - Stack height regulations.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 5 2013-07-01 2013-07-01 false Stack height regulations. 52.2633... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Wyoming § 52.2633 Stack height..., Administrator of The Air Quality Division, the State committed to conduct stack height evaluations in...

  15. 40 CFR 52.345 - Stack height regulations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Stack height regulations. 52.345... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Colorado § 52.345 Stack height regulations. The State of Colorado has committed to revise its stack height regulations should EPA complete rulemaking...

  16. 40 CFR 51.164 - Stack height procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 2 2014-07-01 2014-07-01 false Stack height procedures. 51.164 Section... Modifications § 51.164 Stack height procedures. Such procedures must provide that the degree of emission... source's stack height that exceeds good engineering practice or by any other dispersion technique,...

  17. 40 CFR 52.1034 - Stack height review.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Stack height review. 52.1034 Section 52...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Maine § 52.1034 Stack height review. The... affected by stack height credits greater than good engineering practice or any other prohibited...

  18. 40 CFR 52.383 - Stack height review.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Stack height review. 52.383 Section 52...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Connecticut § 52.383 Stack height review. The State of... by stack height credits greater than good engineering practice or any other prohibited...

  19. 40 CFR 52.2534 - Stack height review.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Stack height review. 52.2534 Section 52...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) West Virginia § 52.2534 Stack height review... emission limits, other than those for the Kammer power plant, have been affected by stack height...

  20. 40 CFR 52.383 - Stack height review.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Stack height review. 52.383 Section 52...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Connecticut § 52.383 Stack height review. The State of... by stack height credits greater than good engineering practice or any other prohibited...