2018 Impact factor 4.843
Particles and Fields
Eur. Phys. J. C 9, 367-381
DOI 10.1007/s100529900065

Measurement of $A_{FB}^{\mathrm{b}\overline{\mathrm{b}}}$in hadronic Z decays using a jet charge technique

The DELPHI Collaboration

P.Abreu21 - et al.

21 LIP, IST, FCUL - Av. Elias Garcia, 14-1o, P-1000 Lisboa Codex, Portugal

Received: 18 December 1998 / Revised version: 2 March 1999 / Published online: 18 June 1999

Abstract
The $\mbox{b}\bar{\mbox{b}}$ forward-backward asymmetry has been determined from the average charge flow measured in a sample of 3,500,000 hadronic Z decays collected with the DELPHI detector in 1992 - 1995. The measurement is performed in an enriched $\mbox{b}\bar{\mbox{b}}$ sample selected using an impact parameter tag and results in the following values for the $\mbox{b}\bar{\mbox{b}}$ forward-backward asymmetry:


\begin{tabular}
{lcl}
 \mbox{\begin{math}
A_{FB}^{{\mathrm{b}}\overline{\mathrm{...
 ...123\,\ \pm0.016\,\ (\mbox{stat.})\pm0.0027(\mbox{syst.})$\space \\ \end{tabular}
The $\mbox{b}\bar{\mbox{b}}$ 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:

\begin{tabular}
{lcl}
\mbox{\begin{math}
{\mathrm{sin}}^2\theta_{\mathrm{eff}}^{\mathrm{l}}\end{math}}& =& $ 0.23186\pm0.00083$\end{tabular}


Copyright Springer-Verlag