Measurement of the forward-backward asymmetry in Z→banti b and Z→canti c

From a sample of 150000 hadronic Z decays collected with the ALEPH detector at LEP, events containing prompt leptons are used to measure the forward-backward asymmetries for the channels Z → banti b and Z → canti c, giving the results AF=Bb = 0.126 ± 0.028 ± 0.012 and AFBc = 0.064 ± 0.039 ± 0.030. These asymmetries correspond to the value of effective electroweak mixing angle at the Z mass sin2ΘW(mZ2) = 0.2262 ± 0.0053. (orig.)