Performance of b-jet identification in the ATLAS experiment

Research output: Contribution to journalArticle


The identification of jets containing b hadrons is important for the physics programme of the ATLAS experiment at the Large Hadron Collider. Several algorithms to identify jets containing b hadrons are described, ranging from those based on the reconstruction of an inclusive secondary vertex or the presence of tracks with large impact parameters to combined tagging algorithms making use of multi-variate discriminants. An independent b-tagging algorithm based on the reconstruction of muons inside jets as well as the b-tagging algorithm used in the online trigger are also presented. The b-jet tagging efficiency, the c-jet tagging efficiency and the mistag rate for light flavour jets in data have been measured with a number of complementary methods. The calibration results are presented as scale factors defined as the ratio of the efficiency (or mistag rate) in data to that in simulation. In the case of b jets, where more than one calibration method exists, the results from the various analyses have been combined taking into account the statistical correlation as well as the correlation of the sources of systematic uncertainty. © CERN 2016 for the benefit of the ATLAS collaboration, published under the terms of the Creative Commons Attribution 3.0 License by IOP Publishing Ltd and Sissa Medialab srl.


External organisations
  • University of Toronto
  • Aix-Marseille University
  • University of Oklahoma
  • Institute of Physics Azerbaijan National Academy of Sciences
  • University of Amsterdam
  • Michigan State University
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Subatomic Physics


  • Large detector systems for particle and astroparticle physics, Large detector-systems performance, Pattern recognition, cluster finding, calibration and fitting methods, Performance of High Energy Physics Detectors, Calibration, Elementary particles, Hadrons, High energy physics, Pattern recognition, Pattern recognition systems, Uncertainty analysis, Astroparticle physics, Complementary methods, Fitting method, High energy physics detector, Large detectors, Large Hadron Collider, Statistical correlation, Systematic uncertainties, Algorithms
Original languageEnglish
Article numberP04008
JournalJournal of Instrumentation
Issue number4
Publication statusPublished - 2016
Publication categoryResearch

Bibliographic note

Cited By :52 Export Date: 23 May 2018