Publicação

A search for t(t)over-bar resonances in lepton plus jets events with highly boosted top quarks collected in pp collisions at root s=7 TeV with the ATLAS detector

Detalhes bibliográficos
Resumo:	A search for resonant production of high-mass top-quark pairs is performed on 2.05 fb−1 of proton-proton collisions at √s=7 TeV collected in 2011 with the ATLAS experiment at the Large Hadron Collider. This analysis of the lepton+jets final state is specifically designed for the particular topology that arises from the decay of highly boosted top quarks. The observed t¯t invariant mass spectrum is found to be compatible with the Standard Model prediction and 95% credibility level upper limits are derived on the t¯t production rate through new massive states. An upper limit of 0.7 pb is set on the production cross section times branching fraction of a narrow 1 TeV resonance. A Kaluza-Klein gluon with a mass smaller than 1.5 TeV is excluded.
Autores principais:	Onofre, A.
Outros Autores:	Castro, Nuno Filipe Silva Fernandes; ATLAS Collaboration
Assunto:	Hadron-Hadron Scattering
Ano:	2012
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:	A search for resonant production of high-mass top-quark pairs is performed on 2.05 fb−1 of proton-proton collisions at √s=7 TeV collected in 2011 with the ATLAS experiment at the Large Hadron Collider. This analysis of the lepton+jets final state is specifically designed for the particular topology that arises from the decay of highly boosted top quarks. The observed t¯t invariant mass spectrum is found to be compatible with the Standard Model prediction and 95% credibility level upper limits are derived on the t¯t production rate through new massive states. An upper limit of 0.7 pb is set on the production cross section times branching fraction of a narrow 1 TeV resonance. A Kaluza-Klein gluon with a mass smaller than 1.5 TeV is excluded.