Study of exclusive two-photon production of $W^+W^-$ in $pp$ collisions at $\sqrt{s} = 7$ TeV and constraints on anomalous quartic gauge couplings

• Autor(a) principal: CMS collaboration (2209 authors)
• Data de Publicação: 2013
• Outros Autores: 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, Nuno
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.26/26431

A search for exclusive or quasi-exclusive W(+)W(−) production by photon-photon interactions, pp → p((*))W(+)W(−)p((*)), at TeV is reported using data collected by the CMS detector with an integrated luminosity of 5.05 fb(−1). Events are selected by requiring a μ (±)e(∓) vertex with no additional associated charged tracks and dilepton transverse momentum p (T)(μ (±)e(∓)) > 30 GeV. Two events passing all selection requirements are observed in the data, compared to a standard model expectation of 2.2 ± 0.4 signal events with 0.84 ± 0.15 background. The tail of the dilepton p (T) distribution is studied for deviations from the standard model. No events are observed with p (T)  > 100 GeV. Model-independent upper limits are computed and compared to predictions involving anomalous quartic gauge couplings. The limits on the parameters with a dipole form factor and an energy cutoff Λ(cutoff) = 500 GeV are of the order of 10(−4).