Dote, A., Bayar, M., Xiao, C. W., Hyodo, T., Oka, M., & Oset, E. (2013). A narrow quasi-bound state of the DNN system. Nucl. Phys. A, 914, 499–504.
Abstract: We have investigated a charmed system of DNN (composed of two nucleons and a D meson) by a complementary study with a variational calculation and a Faddeev calculation with fixed-center approximation (Faddeev-FCA). In the present study, we employ a DN potential based on a vector-meson exchange picture in which a resonant A(c)(2595) is dynamically generated as a DN quasi-bound state, similarly to the A(1405) as a (K) over barN one in the strange sector. As a result of the study of variational calculation with an effective DN potential and three kinds of NN potentials, the DNN(J(pi) =0(-), I = 1/2) is found to be a narrow quasi-bound state below A(c)(2595)N threshold: total binding energy similar to 225 MeV and mesonic decay width similar to 25 MeV. On the other hand, the J(pi) =1(-) state is considered to be a scattering state of A(c)(2595) and a nucleon. These results are essentially supported by the Faddeev-FCA calculation. By the analysis of the variational wave function, we have found a unique structure in the DNN(J(pi) = 0, I = 1/2) such that the D meson stays around the center of the total system due to the heaviness of the D meson.
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Bernabeu, J., Di Domenico, A., & Villanueva-Perez, P. (2013). Direct test of time reversal symmetry in the entangled neutral kaon system at a phi-factory. Nucl. Phys. B, 868(1), 102–119.
Abstract: We present a novel method to perform a direct T (time reversal) symmetry test in the neutral kaon system, independent of any CP and/or CPT symmetry tests. This is based on the comparison of suitable transition probabilities, where the required interchange of in <-> out states for a given process is obtained exploiting the Einstein-Podolski-Rosen correlations of neutral kaon pairs produced at a phi-factory. In the time distribution between the two decays, we compare a reference transition like the one defined by the time-ordered decays (l(-), pi pi) with the T-conjugated one defined by (3 pi(0), l(+)). With the use of this and other T-conjugated comparisons, the KLOE-2 experiment at DA Phi NE could make a statistically significant test.
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de Azcarraga, J. A., Izquierdo, J. M., Lukierski, J., & Woronowicz, M. (2013). Generalizations of Maxwell (super)algebras by the expansion method. Nucl. Phys. B, 869(2), 303–314.
Abstract: The Lie algebras expansion method is used to show that the four-dimensional spacetime Maxwell (super)algebras and some of their generalizations can be derived in a simple way as particular expansions of o(3,2) and osp(N vertical bar 4).
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LHCb Collaboration(Aaij, R. et al), Oyanguren, A., & Ruiz Valls, P. (2013). Observations of B-S(0) ->psi(2S)eta and B-(s)(0) ->psi(2S)pi(+)pi(-) decays. Nucl. Phys. B, 871(3), 403–419.
Abstract: First observations of the B-S(0) ->psi(2S)eta, B-(s)(0) ->psi(2S)pi(+)pi(-) decays are made using a dataset corresponding to an integrated luminosity of 1.0 fb(-1) collected by the LHCb experiment in proton proton collisions at a centre-of-mass energy of root s = 7 TeV. The ratios of the branching fractions of each of the *(2S) modes with respect to the corresponding J/psi decays are B(B-s(0) ->psi(2S)eta)/B(B-s(0) -> J(2S)eta) = 0.83 +/- 0.14 (stat) +/- 0.12 (B), B(B0 ->psi(2S)pi(+)pi(-))/B(B0 -> J/psi pi(+)pi(-)) = 0.56 +/- 0.07 (stat) +/- 0.05 (syst) +/- 0.01 (B), B(B0 ->psi(2S)pi(+)pi(-))/B(B-s(0) -> J/psi pi(+)pi(-)) = 0.34 +/- 0.04 (stat) +/- 0.03 (syst) +/- 0.01 (B). where the third uncertainty corresponds to the uncertainties of the dilepton branching fractions of the J/* and psi(28) meson decays.
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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). Dynamics of isolated-photon plus jet production in pp collisions at root s=7 TeV with the ATLAS detector. Nucl. Phys. B, 875(3), 483–535.
Abstract: The dynamics of isolated-photon plus jet production in pp collisions at a centre-of-mass energy of 7 TeV has been studied with the ATLAS detector at the LHC using an integrated luminosity of 37 pb(-1). Measurements of isolated-photon plus jet bin-averaged cross sections are presented as functions of photon transverse energy, jet transverse momentum and jet rapidity. In addition, the bin-averaged cross sections as functions of the difference between the azimuthal angles of the photon and the jet, the photon jet invariant mass and the scattering angle in the photon jet centre-of-mass frame have been measured. Next-to-leading-order QCD calculations are compared to the measurements and provide a good description of the data, except for the case of the azimuthal opening angle.
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NOMAD Collaboration(Samoylov, O. et al), Cervera-Villanueva, A., Gomez-Cadenas, J. J., & Hernando, J. (2013). A precision measurement of charm dimuon production in neutrino interactions from the NOMAD experiment. Nucl. Phys. B, 876(2), 339–375.
Abstract: We present our new measurement of the cross-section for charm dimuon production in neutrino iron interactions based upon the full statistics collected by the NOMAD experiment. After background subtraction we observe 15 344 charm dimuon events, providing the largest sample currently available. The analysis exploits the large inclusive charged current sample – about 9 x 10(6) events after all analysis cuts – and the high resolution NOMAD detector to constrain the total systematic uncertainty on the ratio of charm dimuon to inclusive Charged Current (CC) cross-sections to similar to 2%. We also perform a fit to the NOMAD data to extract the charm production parameters and the strange quark sea content of the nucleon within the NLO QCD approximation. We obtain a value of m(c)(m(c)) = 1.159 +/- 0.075 GeV/c(2) for the running mass of the charm quark in the (MS) over bar scheme and a strange quark sea suppression factor of kappa(s) = 0.591 +/- 0.019 at Q(2) = 20 GeV2/c(2).
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Chachamis, G., Hentschinski, M., Madrigal Martinez, J. D., & Sabio Vera, A. (2013). Gluon Regge trajectory at two loops from Lipatov's high energy effective action. Nucl. Phys. B, 876(2), 453–472.
Abstract: We present the derivation of the two-loop gluon Regge trajectory using Lipatov's high energy effective action and a direct evaluation of Feynman diagrams. Using a gauge invariant regularization of high energy divergences by deforming the light-cone vectors of the effective action, we determine the two-loop self-energy of the reggeized gluon, after computing the master integrals involved using the Mellin-Barnes representations technique. The self-energy is further matched to QCD through a recently proposed subtraction prescription. The Regge trajectory of the gluon is then defined through renormalization of the reggeized gluon propagator with respect to high energy divergences. Our result is in agreement with previous computations in the literature, providing a non-trivial test of the effective action and the proposed subtraction and renormalization framework.
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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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ATLAS Collaboration(Aad, G. et al), Cabrera Urban, S., Castillo Gimenez, V., Costa, M. J., Fassi, F., Ferrer, A., et al. (2013). Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in root s=7 TeV pp collisions with the ATLAS detector. Phys. Lett. B, 718(3), 841–859.
Abstract: 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 root s = 7 TeV 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.
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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 new phenomena in the WW -> vertical bar v vertical bar ' v ' final state in pp collisions at root s=7 TeV with the ATLAS detector. Phys. Lett. B, 718(3), 860–878.
Abstract: This Letter reports a search for a heavy particle that decays to WW using events produced in pp collisions at root s = 7 TeV. The data were recorded in 2011 by the ATLAS detector and correspond to an integrated luminosity of 4.7 fb(-1). WW -> lvl'v' (l,l' = e or mu) final states are considered and the distribution of the transverse mass of the W W candidates is found to be consistent with Standard Model expectations. Upper limits on the production cross section times branching ratio into W boson pairs are set for Randall-Sundrum and bulk Randall-Sundrum gravitons, which result in observed 95% CL lower limits on the masses of the two particles of 1.23 TeV and 0.84 TeV, respectively.
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