2018 Impact factor 4.843
Particles and Fields
Eur. Phys. J. C 10, 219-237
DOI 10.1007/s100529900122

Measurement of the forward backward asymmetry
of c and b quarks at the Z pole using reconstructed D mesons

The DELPHI Collaboration

P.Abreu21 - et al.

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

Received: 9 February 1999 / Revised version: 26 April 1999 / Published online: 3 August 1999

Abstract
A measurement of the forward-backward asymmetry of $e^{+}e^{-} \to c\bar{c}$ and $e^{+}e^{-} \to b\bar{b}$on the Z resonance is performed using about 3.5 million hadronic Z decays collected by the DELPHI detector at LEP in the years 1992 to 1995. The heavy quark is tagged by the exclusive reconstruction of several D meson decay modes. The forward-backward asymmetries for c and b quarks at the Z resonance are determined to be:

\begin{displaymath}
\begin{array}
{rcr@{\!\!\;\,}l}
{\ifmmode A_{FB}^{c}\else
$A...
 ...\,\, 0.0633\, (stat)\,\, \pm\,\, 0.0122\, (syst) \\ \end{array}\end{displaymath}

The combination of these results leads to an effective electroweak mixing angle of:

\begin{displaymath}
{\ifmmode \sin^2\theta_{eff}^{lept}\else
$\sin^2\theta_{eff}^{lept}$\fi}= 0.2332 \pm 0.0016\end{displaymath}


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