568 research outputs found

    Relativistic Coulomb Sum Rules for (e,e)(e,e^\prime)

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    A Coulomb sum rule is derived for the response of nuclei to (e,e)(e,e^\prime) scattering with large three-momentum transfers. Unlike the nonrelativistic formulation, the relativistic Coulomb sum is restricted to spacelike four-momenta for the most direct connection with experiments; an immediate consequence is that excitations involving antinucleons, e.g., NNˉN{\bar N} pair production, are approximately eliminated from the sum rule. Relativistic recoil and Fermi motion of target nucleons are correctly incorporated. The sum rule decomposes into one- and two-body parts, with correlation information in the second. The one-body part requires information on the nucleon momentum distribution function, which is incorporated by a moment expansion method. The sum rule given through the second moment (RCSR-II) is tested in the Fermi gas model, and is shown to be sufficiently accurate for applications to data.Comment: 32 pages (LaTeX), 4 postscript figures available from the author

    Avaliação de espécies leguminosas na formação de cafezais no segmento da agricultura familiar no Acre.

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    Leguminosas quando consorciadas com o café e usadas como adubação verde podem contribuir fornecendo nitrogênio e proteção ao solo pela adição de matéria orgânica. O trabalho foi conduzido com o objetivo de avaliar o efeito do uso de leguminosas no sistema de produção de café, no segmento de agricultura familiar, visando promover a implantação e a manutenção dos cafezais de forma técnica e economicamente sustentável. O experimento foi conduzido no período de novembro de 2000 a abril de 2003, em delineamento experimental de blocos ao acaso em esquema de parcelas subdivididas, com quatro repetições. Os tratamentos utilizados nas parcelas foram as leguminosas (Stizolobium atterrimum, Cajanus cajan, Canavalia endiformis e Flemingia congesta) e a testemunha (sem leguminosa) e, nas subparcelas, duas doses de N (0 e 22 g de N por cova). A Flemingia congesta e a Mucuna aterrima foram as leguminosas que mais influenciaram positivamente a produtividade dos cafeeiros, independente da adubação nitrogenada. Em relação à testemunha, o aumento em produção foi de 109% quando utilizou-se a Flemingia congesta e 52% com a Mucuna aterrima. A Flemingia congesta foi também a leguminosa que melhor controlou as invasoras, dado o volume de fitomassa produzida e a possibilidade de 2 cortes durante um período de doze meses, evidenciando o potencial desta leguminosa na formação de novos cafezais no Acre. Por outro lado, a Canavalia ensiformis, leguminosa que é normalmente utilizada nas entrelinhas dos cafeeiros pelos cafeicultores, do Acre e de outras regiões produtoras, neste trabalho influenciou negativamente a altura das plantas, diâmetro da copa e crescimento dos cafeeiros

    Differential Geometry applied to Acoustics : Non Linear Propagation in Reissner Beams

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    Although acoustics is one of the disciplines of mechanics, its "geometrization" is still limited to a few areas. As shown in the work on nonlinear propagation in Reissner beams, it seems that an interpretation of the theories of acoustics through the concepts of differential geometry can help to address the non-linear phenomena in their intrinsic qualities. This results in a field of research aimed at establishing and solving dynamic models purged of any artificial nonlinearity by taking advantage of symmetry properties underlying the use of Lie groups. The geometric constructions needed for reduction are presented in the context of the "covariant" approach.Comment: Submitted to GSI2013 - Geometric Science of Informatio

    Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

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    A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

    Measurement of D*+/- meson production in jets from pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

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    This paper reports a measurement of D*+/- meson production in jets from proton-proton collisions at a center-of-mass energy of sqrt(s) = 7 TeV at the CERN Large Hadron Collider. The measurement is based on a data sample recorded with the ATLAS detector with an integrated luminosity of 0.30 pb^-1 for jets with transverse momentum between 25 and 70 GeV in the pseudorapidity range |eta| < 2.5. D*+/- mesons found in jets are fully reconstructed in the decay chain: D*+ -> D0pi+, D0 -> K-pi+, and its charge conjugate. The production rate is found to be N(D*+/-)/N(jet) = 0.025 +/- 0.001(stat.) +/- 0.004(syst.) for D*+/- mesons that carry a fraction z of the jet momentum in the range 0.3 < z < 1. Monte Carlo predictions fail to describe the data at small values of z, and this is most marked at low jet transverse momentum.Comment: 10 pages plus author list (22 pages total), 5 figures, 1 table, matches published version in Physical Review

    Search for supersymmetry in final states with jets, missing transverse momentum and one isolated lepton in sqrt{s} = 7 TeV pp collisions using 1 fb-1 of ATLAS data

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    We present an update of a search for supersymmetry in final states containing jets, missing transverse momentum, and one isolated electron or muon, using 1.04 fb^-1 of proton-proton collision data at sqrt{s} = 7 TeV recorded by the ATLAS experiment at the LHC in the first half of 2011. The analysis is carried out in four distinct signal regions with either three or four jets and variations on the (missing) transverse momentum cuts, resulting in optimized limits for various supersymmetry models. No excess above the standard model background expectation is observed. Limits are set on the visible cross-section of new physics within the kinematic requirements of the search. The results are interpreted as limits on the parameters of the minimal supergravity framework, limits on cross-sections of simplified models with specific squark and gluino decay modes, and limits on parameters of a model with bilinear R-parity violation.Comment: 18 pages plus author list (30 pages total), 9 figures, 4 tables, final version to appear in Physical Review

    Reducing heterotic M-theory to five dimensional supergravity on a manifold with boundary

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    This paper constructs the reduction of heterotic MM-theory in eleven dimensions to a supergravity model on a manifold with boundary in five dimensions using a Calabi-Yau three-fold. New results are presented for the boundary terms in the action and for the boundary conditions on the bulk fields. Some general features of dualisation on a manifold with boundary are used to explain the origin of some topological terms in the action. The effect of gaugino condensation on the fermion boundary conditions leads to a `twist' in the chirality of the gravitino which can provide an uplifting mechanism in the vacuum energy to cancel the cosmological constant after moduli stabilisation.Comment: 16 pages, RevTe

    Communication: Transient Anion States Of Phenol...(h2o) N (n = 1, 2) Complexes: Search For Microsolvation Signatures

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    We report on the shape resonance spectra of phenol-water clusters, as obtained from elastic electron scattering calculations. Our results, along with virtual orbital analysis, indicate that the well-known indirect mechanism for hydrogen elimination in the gas phase is significantly impacted on by microsolvation, due to the competition between vibronic couplings on the solute and solvent molecules. This fact suggests how relevant the solvation effects could be for the electron-driven damage of biomolecules and the biomass delignification [E. M. de Oliveira et al., Phys. Rev. A 86, 020701(R) (2012)]. We also discuss microsolvation signatures in the differential cross sections that could help to identify the solvated complexes and access the composition of gaseous admixtures of these species. © 2014 AIP Publishing LLC.1415NSF; National Stroke FoundationSanche, L., (2005) Eur. Phys. J. D, 35, p. 367. , For a review, see, 10.1140/epjd/e2005-00206-6Wang, C.-R., Nguyen, J., Lu, Q.-B., (2009) J. Am. Chem. Soc., 131, p. 11320. , 10.1021/ja902675gBaccarelli, I., Bald, I., Gianturco, F.A., Illenberger, E., Kopyra, J., (2011) Phys. Rep., 508, p. 1. , 10.1016/j.physre2011.06.004Bettega, M.H.F., Lima, M.A.P., (2007) J. Chem. Phys., 126, p. 194317. , 10.1063/1.2739514De Oliveira, E.M., Lima, M.A.P., Bettega, M.H.F., Sanchez, S.D.A., Da Costa, R.F., Varella, M.T.D.N., (2010) J. Chem. Phys., 132, p. 204301. , 10.1063/1.3428620Baccarelli, I., Grandi, A., Gianturco, F.A., Lucchese, R.R., Sanna, N., (2006) J. Phys. Chem. B, 110, p. 26240. , 10.1021/jp065872nFabrikant, I.I., Caprasecca, S., Gallup, G.A., Gorfinkiel, J.D., (2012) J. Chem. Phys., 136, p. 184301. , 10.1063/1.4706604Freitas, T.C., Lima, M.A.P., Canuto, S., Bettega, M.H.F., (2009) Phys. Rev. A, 80, p. 062710. , 10.1103/PhysRevA.80.062710Freitas, T.C., Coutinho, K., Varella, M.T.D.N., Lima, M.A.P., Canuto, S., Bettega, M.H.F., (2013) J. Chem. Phys., 138, p. 174307. , 10.1063/1.4803119De Oliveira, E.M., Sanchez, S.D.A., Bettega, M.H.F., Natalense, A.P.P., Lima, M.A.P., Do Varella N, M.T., (2012) Phys. Rev. A, 86, pp. 020701-R. , 10.1103/PhysRevA.86.020701Jordan, K.D., Michejda, J.A., Burrow, P.D., (1976) J. Am. Chem. Soc., 98, p. 7189. , 10.1021/ja00439a014Khatymov, R.V., Muftakhov, M.V., Mazunov, V.A., (2003) Rapid Commun. Mass Spectrom., 17, p. 2327. , 10.1002/rcm.1197Dos Santos, J.S., Da Costa, R.F., Varella, M.T.D.N., (2012) J. Chem. Phys., 136, p. 084307. , 10.1063/1.3687345Bettega, M.H.F., Ferreira, L.G., Lima, M.A.P., (1993) Phys. Rev. A, 47, p. 1111. , 10.1103/PhysRevA.47.1111Da Costa, R.F., Da Paixão, F.J., Lima, M.A.P., (2004) J. Phys. B, 37, pp. L129. , 10.1088/0953-4075/37/6/L03Takatsuka, K., McKoy, V., (1981) Phys. Rev. A, 24, p. 2473. , 10.1103/PhysRevA.24.2473Takatsuka, K., McKoy, V., (1984) Phys. Rev. A, 30, p. 1734. , 10.1103/PhysRevA.30.1734Barreto, R.C., Coutinho, K., Georg, H.C., Canuto, S., (2009) Phys. Chem. Chem. Phys., 11, p. 1388. , 10.1039/b816912h(1998) CRC Handbook of Chemistry and Physics, , 79th ed., edited by D. R. Lide (CRC, Boca Raton)http://dx.doi.org/10.1063/1.4892066Nenner, I., Schulz, G.J., (1975) J. Chem. Phys., 62, p. 1747. , 10.1063/1.430700Winstead, C., McKoy, V., (2007) Phys. Rev. Lett., 98, p. 113201. , 10.1103/PhysRevLett.98.113201Winstead, C., McKoy, V., (2007) Phys. Rev. A, 76, p. 012712. , 10.1103/PhysRevA.76.012712Mažín, Z., Gorfinkiel, J.D., (2011) J. Chem. Phys., 135, p. 144308. , 10.1063/1.3650236Modelli, A., Burrow, P.W., (2004) J. Phys. Chem. A, 108, p. 5721. , 10.1021/jp048759aSchmidt, M.W., Baldridge, K.K., Boatz, J.A., Elbert, S.T., Gordon, M.S., Jensen, J.H., Koseki, S., Montgomery, J.A., (1993) J. Comput. Chem., 14, p. 1347. , 10.1002/jcc.540141112Kossoski, F., Bettega, M.H.F., Varella, M.T.D.N., (2014) J. Chem. Phys., 140, p. 024317. , 10.1063/1.4861589Gallup, G., Burrow, P., Fabrikant, I., (2009) Phys. Rev. A, 79, p. 042701. , 10.1103/PhysRevA.79.042701Gallup, G., Burrow, P., Fabrikant, I., (2009) Phys. Rev. A, 80, p. 046702. , 10.1103/PhysRevA.80.046702Scheer, A.M., Mozejko, P., Gallup, G.A., Burrow, P.D., (2007) J. Chem. Phys., 126, p. 174301. , 10.1063/1.2727460Asmis, K.R., Allan, M., Pyrrole Data in the Gallery of Unpublished EEL Spectra, , http://www.chem.unifr.ch/ma/dir_allan/pyrrole_EELS.pdfHaxton, D.J., McCurdy, C.W., Rescigno, T.N., (2007) Phys. Rev. A, 75, p. 012710. , 10.1103/PhysRevA.75.012710Bode, B.M., Gordon, M.S., (1998) J. Mol. Graphics Modell., 16, p. 133. , 10.1016/S1093-3263(99)00002-9Fuke, K., Kaya, K., (1983) Chem. Phys. Lett., 94, p. 97. , 10.1016/0009-2614(83)87218-

    Measurement of tau polarization in W->taunu decays with the ATLAS detector in pp collisions at sqrt(s) = 7 TeV

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    In this paper, a measurement of tau polarization in W->taunu decays is presented. It is measured from the energies of the decay products in hadronic tau decays with a single final state charged particle. The data, corresponding to an integrated luminosity of 24 pb^-1, were collected by the ATLAS experiment at the Large Hadron Collider in 2010. The measured value of the tau polarization is Ptau = -1.06 +/- 0.04 (stat) + 0.05 (syst) - 0.07 (syst), in agreement with the Standard Model prediction, and is consistent with a physically allowed 95% CL interval [-1,-0.91]. Measurements of tau polarization have not previously been made at hadron colliders.Comment: 10 pages plus author list (25 pages total), 4 figures, 4 tables, revised author list, matches published EPJC versio

    Measurement of the correlation between flow harmonics of different order in lead-lead collisions at √sNN = 2.76 TeV with the ATLAS detector

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    Correlations between the elliptic or triangular flow coefficients vm (m=2 or 3) and other flow harmonics vn (n=2 to 5) are measured using √sNN=2.76 TeV Pb+Pb collision data collected in 2010 by the ATLAS experiment at the LHC, corresponding to an integrated luminosity of 7 μb−1. The vm−vn correlations are measured in midrapidity as a function of centrality, and, for events within the same centrality interval, as a function of event ellipticity or triangularity defined in a forward rapidity region. For events within the same centrality interval, v3 is found to be anticorrelated with v2 and this anticorrelation is consistent with similar anticorrelations between the corresponding eccentricities, ε2 and ε3. However, it is observed that v4 increases strongly with v2, and v5 increases strongly with both v2 and v3. The trend and strength of the vm−vn correlations for n=4 and 5 are found to disagree with εm−εn correlations predicted by initial-geometry models. Instead, these correlations are found to be consistent with the combined effects of a linear contribution to vn and a nonlinear term that is a function of v22 or of v2v3, as predicted by hydrodynamic models. A simple two-component fit is used to separate these two contributions. The extracted linear and nonlinear contributions to v4 and v5 are found to be consistent with previously measured event-plane correlations
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