ATLAS b-jet identification performance and efficiency measurement with tt events in pp collisions at √ s = 13 TeV Aad, G. Aguilar Saavedra, Juan Antonio Atlas Collaboration The algorithms used by the ATLAS Collaboration during Run 2 of the Large Hadron Collider to identify jets containing b-hadrons are presented. The performance of the algorithms is evaluated in the simulation and the efficiency with which these algorithms identify jets containing b-hadrons is measured in collision data. The measurement uses a likelihood-based method in a sample highly enriched in tt events. The topology of the t → Wb decays is exploited to simultaneously measure both the jet flavour composition of the sample and the efficiency in a transverse momentum range from 20 to 600 GeV. The efficiency measurement is subsequently compared with that predicted by the simulation. The data used in this measurement, corresponding to a total integrated luminosity of 80.5 fb−1, were collected in proton–proton collisions during the years 2015–2017 at a centre-of-mass energy √ s = 13 TeV. By simultaneously extracting both the efficiency and jet flavour composition, this measurement significantly improves the precision compared to previous results, with uncertainties ranging from 1 to 8% depending on the jet transverse momentum. 2020-01-24T07:28:53Z 2020-01-24T07:28:53Z 2019-11-25 info:eu-repo/semantics/article Aad, G., Abbott, B., Abbott, D.C. et al. ATLAS b-jet identification performance and efficiency measurement with \(t{\bar{t}}\) events in pp collisions at \(\sqrt{s}=13\) TeV. Eur. Phys. J. C 79, 970 (2019). http://hdl.handle.net/10481/59083 10.1140/epjc/s10052-019-7450-8 eng http://creativecommons.org/licenses/by/3.0/es/ info:eu-repo/semantics/openAccess Atribución 3.0 España Springer Nature