Browsing by Issue Date, starting with "2012-10-31"
Now showing 1 - 7 of 7
Results Per Page
Sort Options
- Experimental investigation of transverse spin asymmetries in muon-p SIDIS processes: Collins asymmetriesPublication . COMPASS collaboration (218 authors); Bordalo, P.; Franco, C.; Nunes, A.S.; Quaresma, M.; Quintans, C.; Ramos, S.; Silva, L.; Stolarski, M.The COMPASS Collaboration at CERN has measured the transverse spin azimuthal asymmetry of charged hadrons produced in semi-inclusive deep inelastic scattering using a 160 GeV positive muon beam and a transversely polarised NH_3 target. The Collins asymmetry of the proton was extracted in the Bjorken x range 0.003
- II – Experimental investigation of transverse spin asymmetries in μ -p SIDIS processes: Sivers asymmetriesPublication . COMPASS collaboration (218 authors); Bordalo, P.; Franco, C.; Nunes, A.S.; Quaresma, M.; Quintans, C.; Ramos, S.; Silva, L.; Stolarski, M.The COMPASS Collaboration at CERN has measured the transverse spin azimuthal asymmetry of charged hadrons produced in semi-inclusive deep inelastic scattering using a 160 GeV positive muon beam and a transversely polarised NH_3 target. The Sivers asymmetry of the proton has been extracted in the Bjorken x range 0.003 0.03. The asymmetry is different from zero and positive also in the low x region, where sea-quarks dominate. The kinematic dependence of the asymmetry has also been investigated and results are given for various intervals of hadron and virtual photon fractional energy. In contrast to the case of the Collins asymmetry, the results on the Sivers asymmetry suggest a strong dependence on the four-momentum transfer to the nucleon, in agreement with the most recent calculations.
- Measurement of the top-quark mass in $t\bar{t}$ events with dilepton final states in $pp$ collisions at $\sqrt{s}=7$ TeVPublication . CMS collaboration (2201 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, NunoThe top-quark mass is measured in proton-proton collisions at sqrt(s) = 7 TeV using a data sample corresponding to an integrated luminosity of 5.0 inverse femtobarns collected by the CMS experiment at the LHC. The measurement is performed in the dilepton decay channel t t-bar to ell+ nu[ell] b, ell- anti-nu[ell] b-bar, where ell=e,mu. Candidate top-quark decays are selected by requiring two leptons, at least two jets, and imbalance in transverse momentum. The mass is reconstructed with an analytical matrix weighting technique using distributions derived from simulated samples. Using a maximum-likelihood fit, the top-quark mass is determined to be 172.5 +/- 0.4 (stat) +/- 1.5 (syst) GeV.
- Estudo de implementação de sistemas de Gestão da Qualidade e Acreditação no ensino Superior nas suas várias vertentesPublication . Cardoso, Alda; Varela, Miguel
- Impacto do Petroleo na Economia AngolanaPublication . Macamba, Teotónio; Magalhães, José
- Necessidades de formação profissional de activos a nivel de hotelaria nos distrito de setubalPublication . Pires, Rui; Sarmento, Eduardo
- O Impacto da Inovação nas Organizações: Uma analise ao caso COTECPublication . Dôro, Tânia; Varela, Miguel