Measurement of A FBmathrmboverlinem

Authors: The DELPHI Collaboration P Abreu et al

Publish Date: 1999/06/18

Volume: 9, Issue: 3, Pages: 367-381

PDF Link

Abstract

The mboxbbarmboxb forwardbackward asymmetry has been determined from the average charge flow measured in a sample of 3500000 hadronic Z decays collected with the DELPHI detector in 1992–1995 The measurement is performed in an enriched mboxbbarmboxb sample selected using an impact parameter tag and results in the following values for the mboxbbarmboxb forwardbackward asymmetry begingathered A FBbbar b left 8955 GeV right = 0068 pm 0018 left stat right pm 00013left syst right hfill A FBbbar b left 9126 GeV right = 00982 pm 00047 left stat right pm 00016left syst right hfill A FBbbar b left 9294 GeV right = 0123 pm 0016 left stat right pm 00027left syst right hfill endgathered The mboxbbarmboxb charge separation required for this analysis is directly measured in the b tagged sample while the other charge separations are obtained from a fragmentation model precisely calibrated to data The effective weak mixing angle is deduced from the measurement to be sin2 theta eff1 = 023186 pm 000083

Keywords: