Eur. Phys. J. C 24, 177-191 (2002)
Measurement of the forward-backward asymmetry in and decays with leptonsThe ALEPH Collaboration
(Received: 7 January 2002 / Published online: 26 April 2002 - © Springer-Verlag / Società Italiana di Fisica 2002 )
The sample of hadronic Z decays collected by the ALEPH detector at LEP in the years 1991-1995 is analysed in order to measure the forward-backward asymmetry in and events and the average mixing parameter . Quark charges are tagged by the charges of electrons and muons produced in b and c semileptonic decays. Multivariate analyses are used to separate the event flavours and / processes. The b and c quark asymmetries are measured simultaneously; the average mixing parameter and the pole asymmetries are determined to be
These asymmetries, combined with the ALEPH measurements of the b asymmetry using inclusive b hadron decays and of the c asymmetry using reconstructed D mesons, correspond to a value of the effective electroweak mixing angle of .
© Società Italiana di Fisica, Springer-Verlag 2002