ATLAS <i>b</i>-jet identification performance and efficiency measurement with <i>t</i>(<i>t</i>)over-bar events in <i>pp</i> collisions at √<i>s</i>=13 TeV

Aad, G, Abbott, B, Abbott, DC, Abud, A Abed, Abeling, K, Abhayasinghe, DK, Abidi, SH, AbouZeid, OS, Abraham, NL, Abramowicz, H
et al (show 2901 more authors) (2019) ATLAS <i>b</i>-jet identification performance and efficiency measurement with <i>t</i>(<i>t</i>)over-bar events in <i>pp</i> collisions at √<i>s</i>=13 TeV. EUROPEAN PHYSICAL JOURNAL C, 79 (11). 970-.

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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 of highly enriched in $t\bar{t}$ events. The topology of the $t \to W b$ decays is exploited to simultaneously measure both the jet flavour composition of the sample and the efficiency in a transverse momentum range from 20 GeV 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 to 2017 at a centre-of-mass energy $\sqrt{s}=$ 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.

Item Type: Article
Additional Information: 52 pages in total, author list starting page 36, 12 figures, 6 tables, submitted to EPJC. All figures including auxiliary figures are available at
Uncontrolled Keywords: hep-ex, hep-ex
Depositing User: Symplectic Admin
Date Deposited: 02 Jan 2020 16:59
Last Modified: 11 Oct 2023 03:26
DOI: 10.1140/epjc/s10052-019-7450-8
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