2018 Impact factor 4.843
Particles and Fields
Eur. Phys. J. C 8, 573-584
DOI 10.1007/s100529900020

Measurement of the semileptonic branching ratio
of charm hadrons produced in $Z^{0}\to\mathrm{c}\overline{\mathrm{c}}$ decays

The OPAL Collaboration

G.Abbiendi 2 - et al.

2Dipartimento di Fisica dell' Università di Bologna and INFN, I-40126 Bologna, Italy

Recveived: 17 September 1998 / Published online: 1 March 1999

Abstract
The inclusive charm hadron semileptonic branching fractions ${\rm B}(\mathrm{c}\to{\rm e})$ and ${\rm B}(\mathrm{c}\to\mu)$ in $\mathrm{Z}^0\to\mathrm{c}\bar{\mathrm{c}}$ events have been determined using 4.4 million hadronic $\mathrm{Z}^0$ decays collected with the OPAL detector at LEP. A charm-enriched sample is obtained by selecting events with reconstructed $\mathrm{D}^{*\pm}$ mesons. Using leptons found in the hemisphere opposite that of the $\mathrm{D}^{*\pm}$ mesons, the semileptonic branching fractions of charm hadrons are measured to be

\begin{displaymath}
{\rm B}(\mathrm{c}\to{\rm e})= 0.103 \pm 0.009^{+0.009}_{-0....
 ...\rm B}(\mathrm{c}\to\mu) = 0.090 \pm 0.007^{+0.007}_{-0.006}\,,\end{displaymath}

where the first errors are in each case statistical and the second systematic. Combining these measurements, an inclusive semileptonic branching fraction of charm hadrons of

\begin{displaymath}
{\rm B}(\mathrm{c}\to\ell) = 0.095 \pm {0.006}^{+0.007}_{-0.006}\end{displaymath}

is obtained.


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