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LHCb Collaboration(Aaij, R. et al), Oyanguren, A., & Ruiz Valls, P. (2013). Measurement of the effective B-S(0) -> J/psi K-S(0) lifetime. Nucl. Phys. B, 873(2), 275–292.
Abstract: This paper reports the first measurement of the effective B-S(0) -> J/psi K-S(0) lifetime and an updated measurement of its time-integrated branching fraction. Both measurements are performed with a data sample, corresponding to an integrated luminosity of 1.0 fb(-1) of pp collisions, recorded by the LHCb experiment in 2011 at a centre-of-mass energy of 7 TeV. The results are: tau(eff)(J/psi KS0) = 1.75 +/- 0.12 (stat) +/- 0.07 (syst) ps and B(B-S(0) -> J/psi K-S(0)) = (1.97 +/- 0.23) x 10(-5). For the latter measurement, the uncertainty includes both statistical and systematic sources.
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de Azcarraga, J. A., & Izquierdo, J. M. (2012). D=3 (p, q)-Poincare supergravities from Lie algebra expansions. Nucl. Phys. B, 854(1), 276–291.
Abstract: We use the expansion of superalgebras procedure (summarized in the text) to derive Chem-Simons (CS) actions for the (p, q)-Poincare supergravities in three-dimensional spacetimes. After deriving the action for the (p, 0)-Poincare supergravity as a CS theory for the expansion osp(p vertical bar 2: R)(2, 1) of osp(p vertical bar 2: R), we find the general (p, q)-Poincare superalgebras and their associated D = 3 supergravity actions as CS gauge theories from an expansion of the simple osp(p + q vertical bar 2, R) superalgebras, namely osp(p + q vertical bar 2, R)(2, 1, 2).
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Fonseca, R. M., Malinsky, M., Porod, W., & Staub, F. (2012). Running soft parameters in SUSY models with multiple U(1) gauge factors. Nucl. Phys. B, 854(1), 28–53.
Abstract: We generalize the two-loop renormalization group equations for the parameters of the softly broken SUSY gauge theories given in the literature to the most general case when the gauge group contains more than a single Abelian gauge factor. The complete method is illustrated at two-loop within a specific example and compared to some of the previously proposed partial treatments.
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de Adelhart Toorop, R., Bazzocchi, F., & Morisi, S. (2012). Quark mixing in the discrete dark matter model. Nucl. Phys. B, 856(3), 670–681.
Abstract: We consider a model in which dark matter is stable as it is charged under a Z(2) symmetry that is residual after an A(4) flavour symmetry is broken. We consider the possibility to generate the quark masses by charging the quarks appropriately under A(4). We find that it is possible to generate the CKM mixing matrix by an interplay of renormalisable and dimension-six operators. In this set-up, we predict the third neutrino mixing angle to be large and the dark matter relic density to be in the correct range. Low energy observables – in particular meson-antimeson oscillations – are hard to facilitate. We find that only in a situation where there is a strong cancellation between the Standard Model contribution and the contribution of the new Higgs fields, B meson oscillations are under control.
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Kittel, O., & Pilaftsis, A. (2012). CP violation in correlated production and decay of unstable particles. Nucl. Phys. B, 856(3), 682–697.
Abstract: We study resonant CP-violating Einstein-Podolsky-Rosen correlations that may take place in the production and decay of unstable scalar particles at high-energy colliders. We show that as a consequence of unitarity and CPT invariance of the S-matrix, in 2 -> 2 scatterings mediated by mixed scalar particles, at least three linearly independent decay matrices associated with the unstable scalar states are needed to obtain non-zero CP-odd observables that are also odd under C-conjugation. Instead, for the correlated production and decay of two unstable particle systems in 2 -> 4 processes, we find that only two independent decay matrices are sufficient to induce a net non-vanishing CP-violating phenomenon. As an application of this theorem, we present numerical estimates of CP asymmetries for the correlated production and decay of supersymmetric scalar top anti-top pairs at the LHC, and demonstrate that these could reach values of order one. As a byproduct of our analysis, we develop a novel spinorial trace technique, which enables us to efficiently evaluate lengthy expressions of squared amplitudes describing the resonant scalar transitions.
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Ludl, P. O., Morisi, S., & Peinado, E. (2012). The reactor mixing angle and CP violation with two texture zeros in the light of T2K. Nucl. Phys. B, 857(3), 411–423.
Abstract: We reconsider the phenomenological implications of two texture zeros in symmetric neutrino mass matrices in the light of the recent T2K results for the reactor angle and the new global analysis which gives also best fit values for the Dirac CP phase delta. The most important results of the analysis are: Among the viable cases classified by Frampton etal, only A(1) and A(2) predict theta(13) to be different from zero at 3 sigma. Furthermore these two cases are compatible only with a normal mass spectrum in the allowed region for the reactor angle. At the best fit value A(1) and A(2) predict 0.024 >= sin(2)theta(13) >= 0.012 and 0.014 <= sin(2)theta(13) <= 0.032, respectively, where the bounds on the right and the left correspond to cos delta = -1 and cos delta = 1, respectively. The cases B-1, B-2, B-3 and B-4 predict nearly maximal CP violation, i.e. cos delta approximate to 0.
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Dorame, L., Meloni, D., Morisi, S., Peinado, E., & Valle, J. W. F. (2012). Constraining neutrinoless double beta decay. Nucl. Phys. B, 861(3), 259–270.
Abstract: A class of discrete flavor-symmetry-based models predicts constrained neutrino mass matrix schemes that lead to specific neutrino mass sum-rules (MSR). We show how these theories may constrain the absolute scale of neutrino mass, leading in most of the cases to a lower bound on the neutrinoless double beta decay effective amplitude.
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ATLAS Collaboration(Aad, G. et al), Cabrera Urban, S., Castillo Gimenez, V., Costa, M. J., Ferrer, A., Fiorini, L., et al. (2012). Measurement of the b-hadron production cross section using decays to D*(+)mu X- final states in pp collisions at root s=7 TeV with the ATLAS detector. Nucl. Phys. B, 864(3), 341–381.
Abstract: The b-hadron production cross section is measured with the ATLAS detector in pp collisions at root s = 7 TeV, using 3.3 pb(-1) of integrated luminosity, collected during the 2010 LHC run. The b-hadrons are selected by partially reconstructing D*(+)mu X- final states. Differential cross sections are measured as functions of the transverse momentum and pseudorapidity. The measured production cross section for a b-hadron with p(T) > 9 GeV and vertical bar eta vertical bar < 2.5 is 32.7 +/- 0.8(stat.)(-6.8)(+4.5)(syst.) μb, higher than the next-to-leading-order QCD predictions but consistent within the experimental and theoretical uncertainties.
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Bandos, I. A., de Azcarraga, J. A., & Meliveo, C. (2011). Extended supersymmetry in massless conformal higher spin theory. Nucl. Phys. B, 853(3), 760–776.
Abstract: We propose superfield equations in tensorial N-extended superspaces to describe the N = 2,4,8 supersymmetric generalizations of free conformal higher spin theories. These can be obtained by quantizing a superparticle model in N-extended tensorial superspace. The N-extended higher spin supermultiplets just contain scalar and 'spinor' fields in tensorial space so that, in contrast with the standard (super)space approach, no nontrivial generalizations of the Maxwell or Einstein equations to tensorial space appear when N > 2. For N = 4,8, the higher spin-tensorial components of the extended tensorial superfields are expressed through additional scalar and spinor fields in tensorial space which obey the same free higher spin equations, but that are axion-like in the sense that they possess Peccei-Quinn-like symmetries.
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ATLAS Collaboration(Aad, G. et al), Amoros, G., Cabrera Urban, S., Castillo Gimenez, V., Costa, M. J., Escobar, C., et al. (2011). Measurement of the differential cross-sections of inclusive, prompt and non-prompt J/psi production in proton-proton collisions at sqrt(s)=7 TeV. Nucl. Phys. B, 850(3), 387–444.
Abstract: The inclusive J/psi production cross-section and fraction of J/psi mesons produced in B-hadron decays are measured in proton proton collisions at root s = 7 TeV with the ATLAS detector at the LHC, as a function of the transverse momentum and rapidity of the J/psi, using 2.3 pb(-1) of integrated luminosity. The cross-section is measured from a minimum P(T) of 1 GeV to a maximum of 70 GeV and for rapidities within vertical bar y vertical bar < 2.4 giving the widest reach of any measurement of J/psi production to date. The differential production cross-sections of prompt and non-prompt J/psi are separately determined and are compared to Colour Singlet NNLO*, Colour Evaporation Model, and FONLL predictions.
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