Measurement of B⁰-B̅⁰ flavor oscillations using jet-charge and lepton flavor tagging in pp̅ collisions at √s =1.8 TeV

Authors

F. Abe, National Laboratory for High Energy Physics (KEK), Tsukuba, Ibaraki 305, Japan
Kenneth A. Bloom, University of Nebraska-LincolnFollow
Collider Detector at Fermilab Collaboration

Date of this Version

10-1-1999

Comments

Published by American Physical Society. Phys. Rev. D 60, 072003 (1999). http://prd.aps.org. Copyright © 1999 American Physical Society. Permission to use.

Abstract

We present a measurement of the mass difference Δm_d for the B⁰ meson and the statistical power of the b flavor tagging methods used. The measurement uses 90 pb^-1 of data from pp̅ collisions at √s =1.8 TeV collected with the CDF detector. An inclusive lepton trigger is used to collect a large sample of B hadron semileptonic decays. The mass difference Δm_d is determined from the proper time dependence of the fraction of B hadrons that undergo flavor oscillations. The flavor at decay is inferred from the charge of the lepton from semileptonic B decay. The initial flavor is inferred by determining the flavor of the other B hadron produced in the collision, either from its semileptonic decay (soft-lepton tag) or from its jet charge. The measurement yields Δm_d=(0.500±0.052±0.043)h\ ps^-1, where the first uncertainty is statistical and the second uncertainty is systematic. The statistical powers (εD₂) of the soft-lepton and jet-charge flavor taggers are (0.91±0.10 ±0.11)% and (0.78±0.12±0.08)%, respectively.