TY  - JOUR
T1  - Measurement of the production cross-section of a single top quark in association with a \(Z\) boson in proton-proton collisions at 13 TeV with the ATLAS detector
JF  - Physics letters B
N2  - The production of a top quark in association with a Z boson is investigated. The proton-proton collision data collected by the ATLAS experiment at the LHC in 2015 and 2016 at a centre-of-mass energy of root s = 13 TeV are used, corresponding to an integrated luminosity of 36.1 fb(-1). Events containing three identified leptons (electrons and/or muons) and two jets, one of which is identified as a b-quark jet are selected. The major backgrounds are diboson, tt($)over-bar and Z + jets production. A neural network is used to improve the background rejection and extract the signal. The resulting significance is 4.2 sigma in the data and the expected significance is 5.4 sigma. The measured cross-section for tZq production is 600 +/- 170(stat.)+/- 140(syst.)fb. (C) 2018 The Author(s). Published by Elsevier B.V.
KW  - ATLAS experiment
KW  - proton-proton collisions
KW  - single top quark
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-225406
VL  - 780
ER  - 
TY  - JOUR
T1  - Search for second generation scalar leptoquarks in pp collisions at √s=7 TeV with the ATLAS detector
JF  - The European Physical Journal C
N2  - The results of a search for the production of second generation scalar leptoquarks are presented for final states consisting of either two muons and at least two jets or a muon plus missing transverse momentum and at least two jets. A total of 1.03 fb\(^{−1}\) integrated luminosity of proton-proton collision data produced by the Large Hadron Collider at s√=7 TeV and recorded by the ATLAS detector is used for the search. The event yields in the signal regions are found to be consistent with the Standard Model background expectations. The production of second generation leptoquarks is excluded for a leptoquark mass m\(_{LQ}\)<594 (685) GeV at 95 % confidence level, for a branching ratio of 0.5 (1.0) for leptoquark decay to a muon and a quark.
KW  - jet energy scale
KW  - top quark mass
KW  - multi-jet background
KW  - simulated event sample
KW  - SM background
KW  - acceptance time efficiency
KW  - top quark contribution
KW  - top quark pair
KW  - primary vertex
KW  - single top quark production
KW  - signal cross section
KW  - systematic uncertainty
KW  - single top quark
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-128957
VL  - 72
IS  - 2151
ER  - 
TY  - JOUR
T1  - Measurement of the top quark mass with the template method in the \(t\overline t\)→lepton+jets channel using ATLAS data
JF  - The European Physical Journal C
N2  - The top quark mass has been measured using the template method in the \(t\overline t\)→lepton+jets channel based on data recorded in 2011 with the ATLAS detector at the LHC. The data were taken at a proton-proton centre-of-mass energy of √s=7 TeV and correspond to an integrated luminosity of 1.04 fb\(^{−1}\). The analyses in the e+jets and μ+jets decay channels yield consistent results. The top quark mass is measured to be m\(_{top}\)=174.5±0.6\(_{stat}\)±2.3\(_{syst}\) GeV.
KW  - JES uncertainty
KW  - jet energy scale
KW  - top quark mass
KW  - jet channel
KW  - single top quark
KW  - jet energy scale uncertainty
KW  - systematic uncertainty
KW  - calorimeter response
KW  - simulated signal event
KW  - top quark decay
KW  - jet reconstruction efficiency
KW  - jet energy measurement
KW  - light quark jet
KW  - single top quark production
KW  - inclusive jet sample
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-128912
VL  - 72
IS  - 2046
ER  -