Prompt production in hadronic Z0 decays
Evidence is presented for the production of prompt mesons (not originating in b-hadron decays) in hadronic Z0 decays. Using a sample of 3.6 million hadronic events, 24 prompt candidates are identified from their decays into e+e− and μ+μ− pairs. The background is estimated to be 10.2 ± 2.0 events. The following branching ratio for prompt production is obtained: 0 → prompt