000002054 001__ 2054
000002054 005__ 20200810115402.0
000002054 037__ $$aBELLE2-CONF-PH-2020-004
000002054 041__ $$aeng
000002054 100__ $$aFernando Abudinén
000002054 245__ $$aFirst flavor tagging calibration using 2019 Belle II data
000002054 260__ $$a$$c2020-07-28
000002054 300__ $$a28
000002054 520__ $$aWe report on the first calibration of the standard Belle II B-flavor tagger using the full data set collected at the Upsilon(4S) resonance in 2019 with the Belle II detector at the SuperKEKB collider, corresponding to 8.7/fb of integrated luminosity. The calibration is performed by reconstructing various hadronic charmed B-meson decays with flavor-specific final states. We use simulation to optimize our event selection criteria and to train the flavor tagging algorithm. We determine the tagging efficiency and the fraction of wrongly identified tag-side B candidates from a measurement of the time-integrated B0-anti-B0 mixing probability.  The total effective efficiency is measured to be  33.8 +- 3.6(stat) +- 1.6(sys),  which is in good agreement with the predictions from simulation and comparable with the best one obtained by the Belle experiment. The results show a good understanding of the detector performance and offer a basis for future calibrations.
000002054 6531_ $$aFlavor tagging, flavor mixing, time-dependent CP violation, TDCPV
000002054 700__ $$aTakeo Higuchi
000002054 700__ $$aColm Murphy
000002054 8560_ $$ffernando.jesus.abudinen@desy.de
000002054 8564_ $$uhttps://docs.belle2.org/record/2054/files/BELLE2-CONF-PH-2020-004.pdf