Dehnadi, B., Hoang, A. H., Mateu, V., & Zebarjad, S. M. (2013). Charm mass determination from QCD charmonium sum rules at order alpha(3)(s). J. High Energy Phys., 09(9), 103–56pp.
Abstract: We determine the (MS) over bar charm quark mass from a charmonium QCD sum rules analysis. On the theoretical side we use input from perturbation theory at O (alpha(3)(s)). Improvements with respect to previous O (alpha(3)(s)) analyses include (1) an account of all available e(+)e(-) hadronic cross section data and (2) a thorough analysis of perturbative uncertainties. Using a data clustering method to combine hadronic cross section data sets from di ff erent measurements we demonstrate that using all available experimental data up to c. m. energies of 10 : 538 GeV allows for determinations of experimental moments and their correlations with small errors and that there is no need to rely on theoretical input above the charmonium resonances. We also show that good convergence properties of the perturbative series for the theoretical sum rule moments need to be considered with some care when extracting the charm mass and demonstrate how to set up a suitable set of scale variations to obtain a proper estimate of the perturbative uncertainty. As the fi nal outcome of our analysis we obtain (m(c)) over bar((m(c)) over bar) = 1 : 282 +/- (0.009)(stat) +/- (0.009)(syst) +/- (0.019)(pert) +/- (0.010)(alpha s) +/- (0.002)(< GG >) GeV. The perturbative error is an order of magnitude larger than the one obtained in previous O (alpha(3)(s)) sum rule analyses.
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Garcia Canal, C. A., Tarutina, T., & Vento, V. (2013). Nuclear and partonic dynamics in the EMC effect. Eur. Phys. J. A, 49(8), 105–5pp.
Abstract: It has been recently confirmed that the magnitude of the EMC effect measured in the electron deep inelastic scattering is linearly related to the short-range correlation scaling factor obtained from electron inclusive scattering. By using a x-rescaling approach we are able to understand the interplay between the quark-gluon and hadronic degrees of freedom in the discussion of the EMC effect.
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LHCb Collaboration(Aaij, R. et al), Oyanguren, A., & Ruiz Valls, P. (2013). Search for CP violation in D+ -> phi pi(+) and D-s(+) -> K-S(0)pi(+) decays. J. High Energy Phys., 06(6), 112–20pp.
Abstract: A search for C P violation in D+ -> phi pi(+) decays is performed using data collected in 2011 by the LHCb experiment corresponding to an integrated luminosity of 1.0 fb(-1) at a centre of mass energy of 7 TeV. The CP-violating asymmetry is measured to be (-0.04 +/- 0.14 +/- 0.14)% for candidates with K-K+ mass within 20 MeV/c(2) of the phi meson mass. A search for a CP-violating asymmetry that varies across the phi mass region of the D+ -> K-K+pi(+) Dalitz plot is also performed, and no evidence for CP violation is found. In addition, the CP asymmetry in the D-s(+) -> K-S(0)pi(+) decay is measured to be (0.61 +/- 0.83 +/- 0.14)%.
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Duarte, L., Gonzalez-Sprinberg, G. A., & Vidal, J. (2013). Top quark anomalous tensor couplings in the two-Higgs-doublet models. J. High Energy Phys., 11(11), 114–21pp.
Abstract: We compute the one loop right and left anomalous tensor couplings (g(R) and g(L), respectively) for the top quark, in the aligned two-Higgs-doublet model. They are the magnetic-like couplings in the most general parameterization of the tbW vertex. We find that the aligned two-Higgs doublet model, that includes as particular cases some of the most studied extensions of the Higgs sector, introduces new electroweak contribution's and provides theoretical predictions that are very sensitive to both new scalar masses and the neutral scalar mixing angle. For a largo area in the parameters space we obtain significant deviations in both the real and the imaginary parts of the couplings gR and gL, compared to the predictions given by the electroweak sector of the Standard Model. The most important ones are those involving the imaginary part of the left coupling g(L) and the real part of the right coupling gR. The real part of g(L), and the imaginary part of gR also show an important sensitivity to new physics scenarios. The model can also account for new CP violation effects via the introduction of complex alignment parameters that have important consequences on the values for the imaginary parts of the couplings. The top anomalous tensor couplings will be measured at the LHC and at future colliders providing a complementary insight on new physics, independent from the bounds in top decays coming from B physics and b -> s gamma.
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ATLAS Collaboration(Aad, G. et al), Cabrera Urban, S., Castillo Gimenez, V., Costa, M. J., Fassi, F., Ferrer, A., et al. (2013). Search for resonances decaying into top-quark pairs using fully hadronic decays in pp collisions with ATLAS at root s=7 TeV. J. High Energy Phys., 01(1), 116–50pp.
Abstract: A search for resonances produced in 7 TeV proton-proton collisions and decaying into top-quark pairs is described. In this Letter events where the top-quark decay produces two massive jets with large transverse momenta recorded with the ATLAS detector at the Large Hadron Collider are considered. Two techniques that rely on jet substructure are used to separate top-quark jets from those arising from light quarks and gluons. In addition, each massive jet is required to have evidence of an associated bottom-quark decay. The data are consistent with the Standard Model, and limits can be set on the production cross section times branching fraction of a Z' boson and a Kaluza-Klein gluon resonance. These limits exclude, at the 95% credibility level, Z' bosons with masses 0.70-1.00 TeV as well as 1.28-1.32 TeV and Kaluza-Klein gluons with masses 0.70-1.62 TeV.
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