A search for the standard model production of four top quarks (pp → t t ¯ t t ¯) is reported using single-lepton plus jets and opposite-sign dilepton plus jets signatures. Proton-proton collisions are recorded with the CMS detector at the LHC at a center-of-mass energy of 13 TeV in a sample corresponding to an integrated luminosity of 35.8 fb−1. A multivariate analysis exploiting global event and jet properties is used to discriminate t t ¯ t t ¯ from t t ¯ production. No significant deviation is observed from the predicted background. An upper limit is set on the cross section for t t ¯ t t ¯ production in the standard model of 48 fb at 95% confidence level. When combined with a previous measurement by the CMS experiment from an analysis of other final states, the observed signal significance is 1.4 standard deviations, and the combined cross section measurement is 13−9+11 fb. The result is also interpreted in the framework of effective field theory. [Figure not available: see fulltext.].
Search for the production of four top quarks in the single-lepton and opposite-sign dilepton final states in proton-proton collisions at √s = 13 TeV
Amapane N.;Argiro S.;Bellan R.;Cappati A.;Costa M.;Covarelli R.;Kiani B.;Migliore E.;Monaco V.;Monteil E.;Obertino M. M.;Pacher L.;Pinna Angioni G. L.;Romero A.;Sacchi R.;Salvatico R.;Sola V.;Solano A.;Soldi D.;Shchelina K.;Rumerio P.;Ravera F.;
2019-01-01
Abstract
A search for the standard model production of four top quarks (pp → t t ¯ t t ¯) is reported using single-lepton plus jets and opposite-sign dilepton plus jets signatures. Proton-proton collisions are recorded with the CMS detector at the LHC at a center-of-mass energy of 13 TeV in a sample corresponding to an integrated luminosity of 35.8 fb−1. A multivariate analysis exploiting global event and jet properties is used to discriminate t t ¯ t t ¯ from t t ¯ production. No significant deviation is observed from the predicted background. An upper limit is set on the cross section for t t ¯ t t ¯ production in the standard model of 48 fb at 95% confidence level. When combined with a previous measurement by the CMS experiment from an analysis of other final states, the observed signal significance is 1.4 standard deviations, and the combined cross section measurement is 13−9+11 fb. The result is also interpreted in the framework of effective field theory. [Figure not available: see fulltext.].File | Dimensione | Formato | |
---|---|---|---|
3.pdf
Accesso aperto
Tipo di file:
PDF EDITORIALE
Dimensione
872.78 kB
Formato
Adobe PDF
|
872.78 kB | Adobe PDF | Visualizza/Apri |
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.