Lene Kristian Bryngemark
Researcher
Evidence for single top-quark production in the s-channel in proton–proton collisions at √s=8 TeV with the ATLAS detector using the Matrix Element Method
Author
Summary, in English
This Letter presents evidence for single top-quark production in the s-channel using proton–proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS detector at the CERN Large Hadron Collider. The analysis is performed on events containing one isolated electron or muon, large missing transverse momentum and exactly two b-tagged jets in the final state. The analysed data set corresponds to an integrated luminosity of 20.3 fb−1. The signal is extracted using a maximum-likelihood fit of a discriminant which is based on the matrix element method and optimized in order to separate single-top-quark s-channel events from the main background contributions, which are top-quark pair production and W boson production in association with heavy-flavour jets. The measurement leads to an observed signal significance of 3.2 standard deviations and a measured cross-section of σs=4.8±0.8(stat.)−1.3 +1.6(syst.) pb, which is consistent with the Standard Model expectation. The expected significance for the analysis is 3.9 standard deviations. © 2016 CERN for the benefit of the ATLAS Collaboration
Department/s
- Particle and nuclear physics
- eSSENCE: The e-Science Collaboration
Publishing year
2016
Language
English
Pages
228-246
Publication/Series
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
Volume
756
Document type
Journal article
Publisher
Elsevier
Topic
- Subatomic Physics
Status
Published
ISBN/ISSN/Other
- ISSN: 0370-2693