Search for heavy particles decaying into top-quark pairs using lepton-plus-jets events in proton-proton collisions at root s=13 TeV with the ATLAS detector
EUROPEAN PHYSICAL JOURNAL C, vol.78, no.7, 2018 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Volume: 78 Issue: 7
- Publication Date: 2018
- Doi Number: 10.1140/epjc/s10052-018-5995-6
- Journal Name: EUROPEAN PHYSICAL JOURNAL C
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Istanbul University Affiliated: Yes
Abstract
A search for new heavy particles that decay into top-quark pairs is performed using data collected from proton-proton collisions at a centre-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. The integrated luminosity of the data sample is 36.1 fb(-1). Events consistent with top-quark pair production are selected by requiring a single isolated charged lepton, missing transverse momentum and jet activity compatible with a hadronic top-quark decay. Jets identified as likely to contain b-hadrons are required to reduce the background from other Standard Model processes. The invariant mass spectrum of the candidate top-quark pairs is examined for local excesses above the background expectation. No significant deviations from the Standard Model predictions are found. Exclusion limits are set on the production cross-section times branching ratio for hypothetical Z' bosons, Kaluza-Kein gluons and Kaluza-Klein gravitons that decay into top-quark pairs.