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- Measurement of inclusive W and Z boson production cross sections in pp collisions at $\sqrt{s}$ = 8 TeVPublication . CMS collaboration (2209 authors); Hollar, Jonathan; Nayak, Aruna; Calpas, Betty; Almeida, Nuno; Bargassa, Pedrame; David Tinoco Mendes, Andre; Faccioli, Pietro; Ferreira Parracho, Pedro Guilherme; Gallinaro, Michele; Rodrigues Antunes, Joao; Seixas, Joao; Varela, Joao; Vischia, Pietro; Lloret Iglesias, Lara; Musella, Pasquale; Silva, Pedro; Pela, Joao; Leonardo, NunoA measurement of total and fiducial inclusive W and Z boson production cross sections in pp collisions at $\sqrt{s}$ = 8 TeV is presented. Electron and muon final states are analyzed in a data sample collected with the CMS detector corresponding to an integrated luminosity of 18.2 +/- 0.5 inverse-picobarns. The measured total inclusive cross sections times branching fractions are $\sigma(pp \to WX) \times B(W \to l\nu)$ = 12.21 +/- 0.03 (stat) +/- 0.24 (syst) +/- 0.32 (lum) nb, and $\sigma(pp \to ZX) \times B(Z \to l^{+}l^{-})$ = 1.15 +/- 0.01 (stat) +/- 0.02 (syst) +/- 0.03 (lum) nb, for the dilepton mass in the range of 60 to 120 GeV. The measured values agree with next-to-next-to-leading-order QCD cross section calculations. Ratios of cross sections are reported with a precision of 2%. This is the first measurement of inclusive W and Z boson production in proton-proton collisions at $\sqrt{s}$ = 8 TeV.
- Measurement of the properties of a Higgs boson in the four-lepton final statePublication . CMS collaboration (2207 authors); Hollar, Jonathan; Nayak, Aruna; Calpas, Betty; Bargassa, Pedrame; Beirão Da Cruz E Silva, Cristóvão; Faccioli, Pietro; Ferreira Parracho, Pedro Guilherme; Gallinaro, Michele; Nguyen, Federico; Rodrigues Antunes, Joao; Seixas, Joao; Varela, Joao; Vischia, Pietro; Lloret Iglesias, Lara; David Tinoco Mendes, Andre; Musella, Pasquale; Silva, Pedro; Pela, Joao; Leonardo, NunoThe properties of a Higgs boson candidate are measured in the H to ZZ to 4l decay channel, with l = e, mu, using data from pp collisions corresponding to an integrated luminosity of 5.1 inverse femtobarns at the center-of-mass energy of sqrt(s) = 7 TeV and 19.7 inverse femtobarns at sqrt(s) = 8 TeV, recorded with the CMS detector at the LHC. The new boson is observed as a narrow resonance with a local significance of 6.8 standard deviations, a measured mass of 125.6 +- 0.4 (stat) +- 0.2 (syst) GeV, and a total width less than 3.4 GeV at the 95% confidence level. The production cross section of the new boson times its branching fraction to four leptons is measured to be 0.93 +0.26 -0.23 (stat) +0.13 -0.09 (syst) times that predicted by the standard model. Its spin-parity properties are found to be consistent with the expectations for the standard model Higgs boson. The hypotheses of a pseudoscalar and all tested spin-one boson hypotheses are excluded at the 99% confidence level or higher. All tested spin-two boson hypotheses are excluded at the 95% confidence level or higher.
- Robot localization from minimalist inertial data using a Hidden Markov ModelPublication . Abreu, AntónioHidden Markov Models (HMM) are applied to interoceptive data (in this case the sense of rotation by way of a gyroscope) acquired by a moving wheeled robot when contouring an indoor environment. We demonstrate the soundness of HMM to solve the problem of robot localization in a topological model of the environment, particularly the kidnapped robot problem and position tracking. In this approach, the environment topology is described by the sequence of movements a robot executes when contouring the environment. Movements are described in a fuzzy domain using distance traveled and curvature as features.
- A agradabilidade de vozes disfónicas em adolescentesPublication . Bastos, Ana Catarina; Quintal, Aldora; Correia, Paula; Martins, Ana Paula