Search for excited electrons and muons in s√=8 TeV proton-proton collisions with the ATLAS detector

• Autor(a) principal: Onofre, A.
• Data de Publicação: 2013
• Outros Autores: Castro, Nuno Filipe Silva Fernandes, ATLAS Collaboration
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/1822/31926
• topic: Ciências Naturais::Ciências Físicas; Science & Technology

The ATLAS detector at the Large Hadron Collider is used to search for excited electrons and excited muons in the channel pp → ``∗ → ``γ , assuming that excited leptons are produced via contact interactions. The analysis is based on 13 fb−1 of pp collisions at a centre-of-mass energy of 8 TeV. No evidence for excited leptons is found, and a limit is set at the 95% credibility level on the cross section times branching ratio as a function of the excitedlepton mass m` ∗ . For m` ∗ > 0.8 TeV, the respective upper limits on σ B(`∗ → `γ ) are 0.75 and 0.90 fb for the e ∗ and µ ∗ searches. Limits on σ B are converted into lower bounds on the compositeness scale 3. In the special case where 3 = m` ∗ , excited-electron and excited-muon masses below 2.2 TeV are excluded.