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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. (2014). Fiducial and differential cross sections of Higgs boson production measured in the four-lepton decay channel in pp collisions at root s=8 TeV with the ATLAS detector. Phys. Lett. B, 738, 234–253.
Abstract: Measurements of fiducial and differential cross sections of Higgs boson production in the H -> ZZ* -> 4l decay channel are presented. The cross sections are determined within a fiducial phase space and corrected for detection efficiency and resolution effects. They are based on 20.3 fb(-1) of pp collision data, produced at root s= 8 TeV centre-of-mass energy at the LHC and recorded by the ATLAS detector. The differential measurements are performed in bins of transverse momentum and rapidity of the four-lepton system, the invariant mass of the subleading lepton pair and the decay angle of the leading lepton pair with respect to the beam line in the four-lepton rest frame, as well as the number of jets and the transverse momentum of the leading jet. The measured cross sections are compared to selected theoretical calculations of the Standard Model expectations. No significant deviation from any of the tested predictions is found.
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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. (2014). Muon reconstruction efficiency and momentum resolution of the ATLAS experiment in proton-proton collisions at root s=7 TeV in 2010. Eur. Phys. J. C, 74(9), 3034–32pp.
Abstract: This paper presents a study of the performance of the muon reconstruction in the analysis of proton-proton collisions at root s = 7TeV at the LHC, recorded by the ATLAS detector in 2010. This performance is described in terms of reconstruction and isolation efficiencies and momentum resolutions for different classes of reconstructed muons. The results are obtained from an analysis of J/psi meson and Z boson decays to dimuons, reconstructed from a data sample corresponding to an integrated luminosity of 40 pb(-1). The measured performance is compared to Monte Carlo predictions and deviations from the predicted performance are discussed.
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Aydin, S. et al, Gadea, A., & Huyuk, T. (2014). High-spin level structure of S-35. Phys. Rev. C, 89(1), 014310–9pp.
Abstract: The nucleus S-35 has been studied by in-beam gamma-ray spectroscopy using the Mg-24(N-14,3p) fusion-evaporation reaction at E-lab = 40 MeV. A level scheme extended up to J(pi) = 17/2(+) at 8023 keV and J(pi) = 13/2(-) at 6352 keV has been established. Lifetimes of six excited states have been determined by applying the Doppler shift attenuation method. The experimental data have been compared with the results of large-scale shell model calculations performed using different effective interactions and model spaces allowing particle-hole excitations across the N = Z = 20 shell gap.
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BABAR Collaboration(Lees, J. P. et al), Martinez-Vidal, F., & Oyanguren, A. (2014). Study of the reaction e(+)e(-) -> psi(2S)pi(+)pi(-) via initial-state radiation at BABAR. Phys. Rev. D, 89(11), 111103–8pp.
Abstract: We study the process e(+)e(-) -> psi(2S)pi(+)pi(-) with initial-state-radiation events produced at the PEP-II asymmetric-energy collider. The data were recorded with the BABAR detector at center-of-mass energies at and near the (nS) (n = 2, 3, 4) resonances and correspond to an integrated luminosity of 520 fb(-1). We investigate the psi(2S)pi(+)pi(-) mass distribution from 3.95 to 5.95 GeV/c(2), and measure the center-of-mass energy dependence of the associated e(+)e(-) -> psi(2S)pi(+)pi(-) cross section. The mass distribution exhibits evidence of two resonant structures. A fit to the psi(2S)pi(+)pi(-) mass distribution corresponding to the decay mode psi(2S) -> J/psi pi(+)pi(-) yields a mass value of 4340 +/- 16 (stat) +/- 9 (syst) MeV/c(2) and a width of 94 +/- 32 (stat) +/- 13 (syst) MeV for the first resonance, and for the second a mass value of 4669 +/- 21 (stat) +/- 3 (syst) MeV/c(2) and a width of 104 +/- 48 (stat) +/- 10 (syst) MeV. In addition, we show the pi(+)pi(-) mass distributions for these resonant regions.
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BABAR Collaboration(Lees, J. P. et al), Martinez-Vidal, F., Oyanguren, A., & Villanueva-Perez, P. (2014). Search for lepton-number violating B+ -> X(-)l(+)l '(+) decays. Phys. Rev. D, 89(1), 011102–8pp.
Abstract: We report on a search for eleven lepton-number violating processes B+ -> X(-)l(+)l'(+) with X- = K-, pi(-), rho(-), K*(-), or D- and l(+)/l'(+) = e(+) or mu(+), using a sample of 471 +/- 3 million B (B) over bar events collected with the BABAR detector at the PEP-II e(+)e(-) collider at the SLAC National Accelerator Laboratory. We find no evidence for any of these modes and place 90% confidence level upper limits on their branching fractions in the range (1.5-26) x 10(-7).
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