Configuration and performance of the ATLAS b-jet triggers in Run 2
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.
Aad, G; Abbott, B; Abbott, DC; Abed Abud, A; Abeling, K; Abhayasinghe, DK; Abidi, SH; AbouZeid, OS; Abraham, NL; Abramowicz, H; Abreu, H; Abulaiti, Y; Acharya, BS; Achkar, B; Adam, L; Adam Bourdarios, C; Adamczyk, L; Adamek, L; Adelman, J; Adiguzel, A; Adorni, S; Adye, T; Affolder, AA; Afik, Y; Agapopoulou, C; Agaras, MN; Aggarwal, A; Agheorghiesei, C; Aguilar-Saavedra, JA; Ahmad, A; Ahmadov, F; Ahmed, WS; Ai, X; Aielli, G; Akatsuka, S; Akbiyik, M; Åkesson, TPA; Akilli, E; Akimov, AV; Al Khoury, K; Alberghi, GL; Albert, J; Alconada Verzini, MJ; Alderweireldt, S; Aleksa, M; Aleksandrov, IN; Alexa, C; Alexopoulos, T; Alfonsi, A; Alfonsi, F; Alhroob, M; Ali, B; Ali, S; Aliev, M; Alimonti, G; Alison, J; Allaire, C; Allbrooke, BMM; Allport, PP; Aloisio, A; Alonso, F; Alpigiani, C; Alunno Camelia, E; Alvarez Estevez, M; Alviggi, MG; Amaral Coutinho, Y; Ambler, A; Ambroz, L; Amelung, C; Amidei, D; Amor Dos Santos, SP; Amoroso, S; Amrouche, CS; Anastopoulos, C; Andari, N; Andeen, T; Anders, JK; Andrean, SY; Andreazza, A; Andrei, V; Anelli, CR; Angelidakis, S; Angerami, A; Anisenkov, AV; Annovi, A; Antel, C; Anthony, MT; Antipov, E; Antonelli, M; Antrim, DJA; Anulli, F; Aoki, M; Aparisi Pozo, JA; Aparo, MA; Aperio Bella, L; Aranzabal, N; Araujo Ferraz, V; Pereira, RA; Arcangeletti, C; Arce, ATH
Volume / Issue
Electronic International Standard Serial Number (EISSN)
International Standard Serial Number (ISSN)
Digital Object Identifier (DOI)