INVESTIGADORES
MONTICELLI Fernando Gabriel
artículos
Título:
Measurement of the tt¯ production cross-section using eμ events with b-tagged jets in pp collisions at s√=13 TeV with the ATLAS detector
Autor/es:
F. MONTICELLI; ATLAS
Revista:
PHYSICS LETTERS B
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Lugar: Amsterdam; Año: 2016
ISSN:
0370-2693
Resumen:
This paper describes a measurement of the inclusive top quark pair production cross-section ( σtt¯ ) with a data sample of 3.2fb−1 of proton?proton collisions at a centre-of-mass energy of $\sqrt s%=13TeV , collected in 2015 by the ATLAS detector at the LHC. This measurement uses events with an opposite-charge electron?muon pair in the final state. Jets containing b -quarks are tagged using an algorithm based on track impact parameters and reconstructed secondary vertices. The numbers of events with exactly one and exactly two b -tagged jets are counted and used to determine simultaneously σtt¯ and the efficiency to reconstruct and b -tag a jet from a top quark decay, thereby minimising the associated systematic uncertainties. The cross-section is measured to be: σtt¯=818±8(stat)±27(syst)±19(lumi)±12(beam) pb, where the four uncertainties arise from data statistics, experimental and theoretical systematic effects, the integrated luminosity and the LHC beam energy, giving a total relative uncertainty of 4.4%. The result is consistent with theoretical QCD calculations at next-to-next-to-leading order. A fiducial measurement corresponding to the experimental acceptance of the leptons is also presented.