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- Search for new physics in events with photons, jets, and missing transverse energy in $pp$ collisions at $\sqrt{s}=7$ TeVPublication . CMS collaboration (2197 authors); Hollar, Jonathan; Nayak, Aruna; Almeida, Nuno; Bargassa, Pedrame; David Tinoco Mendes, Andre; Faccioli, Pietro; Ferreira Parracho, Pedro Guilherme; Gallinaro, Michele; Seixas, Joao; Varela, Joao; Vischia, Pietro; Lloret Iglesias, Lara; Musella, Pasquale; Rodrigues Antunes, Joao; Silva, Pedro; Pela, Joao; Leonardo, NunoA search for physics beyond the standard model involving events with one or more photons, jets, and missing transverse energy has been performed by the CMS experiment. The data sample corresponds to an integrated luminosity of 4.93 fb(−1) of proton-proton collisions at TeV, produced at the Large Hadron Collider. No excess of events with large missing transverse energy is observed beyond expectations from standard model processes, and upper limits on the signal production cross sections for new physics processes are set at the 95% confidence level. The results of this search are interpreted in the context of three models of new physics: a general model of gauge-mediated supersymmetry breaking, Simplified Models, and a theory involving universal extra dimensions. In the absence of evidence for new physics, exclusion regions are derived in the parameter spaces of the respective models.
- Measurement of differential top-quark pair production cross sections in $pp$ colisions at $\sqrt{s}=7$ TeVPublication . CMS collaboration (2199 authors); Hollar, Jonathan; Nayak, Aruna; Almeida, Nuno; Bargassa, Pedrame; David Tinoco Mendes, Andre; Faccioli, Pietro; Ferreira Parracho, Pedro Guilherme; Gallinaro, Michele; Seixas, Joao; Varela, Joao; Vischia, Pietro; Lloret Iglesias, Lara; Musella, Pasquale; Rodrigues Antunes, Joao; Silva, Pedro; Pela, Joao; Leonardo, NunoNormalised differential top-quark-pair production cross sections are measured in pp collisions at a centre-of-mass energy of 7 TeVat the LHC with the CMS detector using data recorded in 2011 corresponding to an integrated luminosity of 5.0 fb(−1). The measurements are performed in the lepton+jets decay channels (e+jets and μ+jets) and the dilepton decay channels ( , μ (+) μ (−), and μ (±)e(∓)). The differential cross section is measured as a function of kinematic properties of the final-state charged leptons and jets associated to b quarks, as well as those of the top quarks and the system. The data are compared with several predictions from perturbative QCD calculations up to approximate next-to-next-to-leading-order precision. No significant deviations from the standard model are observed.