Publicação

Search for charged Higgs bosons in the H-+/- -> tb decay channel in pp collisions at root s=8 TeV using the ATLAS detector

Ver documento

Detalhes bibliográficos
Resumo:Charged Higgs bosons heavier than the top quark and decaying via H± → tb are searched for in proton-proton collisions measured with the ATLAS experiment at s√=8 TeV corresponding to an integrated luminosity of 20.3fb−1. The production of a charged Higgs boson in association with a top quark, gb → tH±, is explored in the mass range 200 to 600 GeV using multi-jet final states with one electron or muon. In order to separate the signal from the Standard Model background, analysis techniques combining several kinematic variables are employed. An excess of events above the background-only hypothesis is observed across a wide mass range, amounting to up to 2.4 standard deviations. Upper limits are set on the gb → tH± production cross section times the branching fraction BR(H± → tb). Additionally, the complementary s-channel production, qq′ → H±, is investigated through a reinterpretation of W′ → tb searches in ATLAS. Final states with one electron or muon are relevant for H± masses from 0.4 to 2.0 TeV, whereas the all-hadronic final state covers the range 1.5 to 3.0 TeV. In these search channels, no significant excesses from the predictions of the Standard Model are observed, and upper limits are placed on the qq′ → H± production cross section times the branching fraction BR(H± → tb).
Autores principais:Onofre, A.
Outros Autores:Castro, Nuno Filipe Silva Fernandes; ATLAS Collaboration
Assunto:Hadron-Hadron scattering Higgs physics
Ano:2016
País:Portugal
Tipo de documento:artigo
Tipo de acesso:acesso aberto
Instituição associada:Universidade do Minho
Idioma:inglês
Origem:RepositóriUM - Universidade do Minho
Descrição
Resumo:Charged Higgs bosons heavier than the top quark and decaying via H± → tb are searched for in proton-proton collisions measured with the ATLAS experiment at s√=8 TeV corresponding to an integrated luminosity of 20.3fb−1. The production of a charged Higgs boson in association with a top quark, gb → tH±, is explored in the mass range 200 to 600 GeV using multi-jet final states with one electron or muon. In order to separate the signal from the Standard Model background, analysis techniques combining several kinematic variables are employed. An excess of events above the background-only hypothesis is observed across a wide mass range, amounting to up to 2.4 standard deviations. Upper limits are set on the gb → tH± production cross section times the branching fraction BR(H± → tb). Additionally, the complementary s-channel production, qq′ → H±, is investigated through a reinterpretation of W′ → tb searches in ATLAS. Final states with one electron or muon are relevant for H± masses from 0.4 to 2.0 TeV, whereas the all-hadronic final state covers the range 1.5 to 3.0 TeV. In these search channels, no significant excesses from the predictions of the Standard Model are observed, and upper limits are placed on the qq′ → H± production cross section times the branching fraction BR(H± → tb).