The European Physical Journal C - Particles and Fields

, Volume 12, Issue 2, pp 225–241

Measurements of the Z partial decay width into \(c\bar c\) and multiplicity of charm quarks per b decay

  • The DELPHI Collaboration
  • P. Abreu et al.
Experimental physics

DOI: 10.1007/s1005299000228

Cite this article as:
The DELPHI Collaboration & Abreu et al., P. Eur. Phys. J. C (2000) 12: 225. doi:10.1007/s1005299000228


The partial decay width \(R_c\) of the Z into \(c\bar c\) quark pair and the number of charm quarks \(n_c\) per b decay are measured with the DELPHI detector at LEP 1. Particle identification provides clear \(D^0\), \(D^+\), \(D_s^+\) and \(\Lambda_c^+\) signatures. The charm hadron production rate is measured in each channel by a fit to the scaled energy, impact parameter information and the invariant mass spectrum. Two measurements of \(R_c\) are presented, from the \(D^{*+}\) production rate and from the overall charm counting, including strange charm baryon production, in \(c\bar c\) events. The multiplicity \(n_c\), which includes hidden \(c\bar c\) and strange charm baryon production, is inferred from the charm counting in \(b\bar{b}\) events. The final results are \(R_c = 0.1665 \pm 0.0095\) and \(n_c = 1.166 \pm 0.086\).

Copyright information

© Springer-Verlag Berlin Heidelberg 2000

Authors and Affiliations

  • The DELPHI Collaboration
  • P. Abreu et al.
    • 1
  1. 1.LIP, IST, FCUL - Av. Elias Garcia, 14-1° 1000 Lisboa Codex, PortugalPT