Determination of and at LEP 1
The DELPHI Collaboration
P.Abreu21 - et al.
21 LIP, IST, FCUL - Av. Elias Garcia, 14-1o,
PT-1000 Lisboa Codex, Portugal
Received: 1 June 1999 / Published online: 8 December 1999
The probability that a charm quark fragments into a D*+ meson and the semileptonic branching fraction were measured in decay into events.
From the analysis of 3.5 Million events collected from 1992 to 1995, a sample of charm meson decays with purity was selected. The product of the fragmentation probability times the branching fraction was measured to be:
Using the world averaged value for , the fragmentation probability is inferred:
From the same sample, identified leptons in the opposite hemisphere were selected. From this sample, the charm semileptonic branching fraction was measured to be:
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