Four top quarks and the tt¯ forward-backward asymmetry
Metadatos
Mostrar el registro completo del ítemEditorial
American Physical Society
Materia
Top quark Forward-backward (FB) Asymmetry
Fecha
2012Referencia bibliográfica
Aguilar-Saavedra, J.A.; Santiago, J. Four top quarks and the tt¯ forward-backward asymmetry. Physical Review D, 85: 034021 (2012). [http://hdl.handle.net/10481/30530]
Patrocinador
This work has been partially supported by MICINN project FPA2006-05294, FPA2010-17915 and Junta de Andalucía projects FQM 101, FQM 03048 and FQM 6552.Resumen
New colour octet vectors below the TeV scale could explain the anomalous t tbar forward-backward asymmetry observed at the Tevatron experiments, while being consistent with the current LHC data. These models generally lead to four-top final states at the LHC at observable levels. We compute the four-top production cross section at the LHC in a model with a massive colour octet vector as a function its mass, its width and its coupling to the top quark. Octet masses in the vicinity of the t tbar threshold are generally excluded by present limits on the production of same-sign dileptons and trileptons. Masses above 650 GeV are allowed, quite independently of the couplings, but they can be probed with the luminosity of 5 fb^-1 already collected at the LHC, up to around 800 GeV. The four-top production cross section is increased by a factor ~ 2 with sqrt{s}=8 TeV and by up to almost two orders of magnitude with sqrt{s}=14 TeV, thus greatly increasing the reach for massive gluons after the LHC energy upgrade.