Procura do bóson de Higgs no canal de decaimento H → WW → lνjj em colisões pp a 8 TeV com o detector CMS do LHC utilizando a técnica de elemento de matriz

• Autor(a) principal: Custódio, Analu Verçosa
• Data de Publicação: 2016
• Outros Autores: [e-mail]
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/17092
• topic: Higgs bosons; Matrices; Compact muon solenoid; Large hadron collider (France and Switzerland); Matrix element; CMS; Higgs, Bósons de; Matrizes (Matemática); Solenóide de múon compacto; Grande colisor de hádrons (França e Suíça); Bóson de Higgs; Elemento de matriz; CMS; CIENCIAS EXATAS E DA TERRA::FISICA::FISICA DAS PARTICULAS ELEMENTARES E CAMPOS

The LHC experiments CMS and ATLAS have observed the Higgs boson particle with a mass of 125 GeV. Because of the Higgs boson's small cross section, this is a difficult task and requires sophisticated methods to analyse the data. In this thesis, the study of a Higgs boson decaying into a pair of W bosons and subsequently in a lepton-neutrino pair and two jets (H → WW → lνjj) is presented. Since no narrow mass peak can be reconstructed, a good understanding of the background is necessary. The most important background for this analysis is the production of the inclusive W + jets process. For this analysis, we propose a new method for event identification, based in the matrix element of the process (Feynman amplitude) extracted from the theoretical hypothesis. The matrix element method is appropriate for rare events since it maximizes the experimental information. Higgs boson mass hypotheses of 170, 180, 190, 200, 250, 300, 350, 400, 450, 500 and 550 GeV were analysed and no evidence of a Higgs boson in this mass range was found.