Skip to main content

Advertisement

Log in

Inclusive semileptonic branching ratios of b hadrons produced in Z decays

  • Experimental physics
  • Published:
The European Physical Journal C - Particles and Fields Aims and scope Submit manuscript

Abstract.

A measurement of the inclusive semileptonic branching ratios of b hadrons produced in Z decay is presented, using four million hadronic events collected by the ALEPH detector from 1991 to 1995. Electrons and muons are selected opposite to b-tagged hemispheres. Two different methods are explored to distinguish the contributions from direct \({{\mathrm b}\to{\mathrm{X}}\ell \nu}\) and cascade \({{\mathrm b}\to{\mathrm c}\to{\mathrm X} \ell \nu}\) decays to the total lepton yield. One is based on the lepton transverse momentum spectrum, the other makes use of the correlation between the charge of the lepton and charge estimators built from tracks in the opposite hemisphere of the event. The latter method reduces the dependence on the modelling of semileptonic b decays. The results obtained by averaging the two techniques are

\begin{eqnarray} {\mathrm{BR}}({\mathrm b}\to{\mathrm{X}} \ell \nu)& = & 0.1070 \pm 0.0010 _{\mathrm{stat}} \pm 0.0023 _{\mathrm{syst}} \pm 0.0026 _{\mathrm{model}} , \nonumber {\mathrm{BR}}({\mathrm b}\to{\mathrm c}\to{\mathrm X} \ell \nu)& = & 0.0818 \pm 0.0015 _{\mathrm{stat}} \pm 0.0022 _{\mathrm{syst}} {^{+0.0010} _{-0.0014}} _{\mathrm{model}} . \nonumber \end{eqnarray}

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

Author information

Authors and Affiliations

Authors

Consortia

Additional information

Received: 1 August 2001 / Published online: 14 December 2001

Rights and permissions

Reprints and permissions

About this article

Cite this article

The ALEPH Collaboration., Heister et al., A. Inclusive semileptonic branching ratios of b hadrons produced in Z decays. Eur. Phys. J. C 22, 613–626 (2002). https://doi.org/10.1007/s100520100851

Download citation

  • Issue Date:

  • DOI: https://doi.org/10.1007/s100520100851

Keywords

Navigation