A measurement of the relative decay rate of the charm quark into leptons

The inclusive rate of leptons produced from charmed particle decays (from Z -> charm anticharm) has been measured using a data sample of four million hgadronic Z decays recorded by the ALEPH experiment at LEP from 1991 to 1995. The analysis uses a double-tag and is self-calibrating, i.e. it makes minimum use of the Monte Carlo simulated information. Each event is divided into two hemispheres; hemispheres containing charm quarks are identified with a NEural Network anlaysis method. Lepton candidates are then searched for in the opposite hemisphere. Based on fully reconstructed D candidates, a value of BR(c -> l + X) = 9.09 +/- 0.61 % (l = e or mu) is obtained. The uncertainy includes both the statistical and systematic components.

Level thesis:degree_level

thesis.doctoral

Grantor dc:publisher

Ludwig-Maximilians-Universität

Year

2003

Author dc:creator

• David, Aretina Magdalena

Repository record source_url

https://edoc.ub.uni-muenchen.de/841/

OAI identifier oai:identifier

oai:edoc.ub.uni-muenchen.de:841