%0 Journal Article %T Configuration and performance of the ATLAS b-jet triggers in Run 2 %A ATLAS Collaboration (Aad, G. et al %A Aparisi Pozo, J. A. %A Bailey, A. J. %A Cabrera Urban, S. %A Cardillo, F. %A Castillo, F. L. %A Castillo Gimenez, V. %A Costa, M. J. %A Escobar, C. %A Estrada Pastor, O. %A Fiorini, L. %A Fullana Torregrosa, E. %A Fuster, J. %A Garcia, C. %A Garcia Navarro, J. E. %A Gonzalez de la Hoz, S. %A Gonzalvo Rodriguez, G. R. %A Guerrero Rojas, J. G. R. %A Higon-Rodriguez, E. %A Lacasta, C. %A Lozano Bahilo, J. J. %A Mamuzic, J. %A Marti-Garcia, S. %A Martinez Agullo, P. %A Mitsou, V. A. %A Moreno Llacer, M. %A Navarro-Gonzalez, J. %A Poveda, J. %A Prades IbaƱez, A. %A Rodriguez Bosca, S. %A Ruiz-Martinez, A. %A Sabatini, P. %A Salt, J. %A Santra, A. %A Sayago Galvan, I. %A Soldevila, U. %A Sanchez, J. %A Torro Pastor, E. %A Valero, A. %A Valls Ferrer, J. A. %A Villaplana Perez, M. %A Vos, M. %J European Physical Journal C %D 2021 %V 81 %N 12 %I Springer %@ 1434-6044 %G English %F ATLASCollaborationAad_etal2021 %O WOS:000728553000002 %O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=5048), last updated on Mon, 20 Dec 2021 09:43:33 +0000 %X Several improvements to the ATLAS triggers used to identify jets containing b-hadrons (b-jets) were implemented for data-taking during Run 2 of the Large Hadron Collider from 2016 to 2018. These changes include reconfiguring the b-jet trigger software to improve primary-vertex finding and allow more stable running in conditions with high pile-up, and the implementation of the functionality needed to run sophisticated taggers used by the offline reconstruction in an online environment. These improvements yielded an order of magnitude better light-flavour jet rejection for the same b-jet identification efficiency compared to the performance in Run 1 (2011-2012). The efficiency to identify b-jets in the trigger, and the conditional efficiency for b-jets that satisfy offline b-tagging requirements to pass the trigger are also measured. Correction factors are derived to calibrate the b-tagging efficiency in simulation to match that observed in data. The associated systematic uncertainties are substantially smaller than in previous measurements. In addition, b-jet triggers were operated for the first time during heavy-ion data-taking, using dedicated triggers that were developed to identify semileptonic b-hadron decays by selecting events with geometrically overlapping muons and jets. %R 10.1140/epjc/s10052-021-09775-5 %U https://arxiv.org/abs/2106.03584 %U https://doi.org/10.1140/epjc/s10052-021-09775-5 %P 1087-45pp