O ct 2 00 1 A New Measurement of the Ξ + c Lifetime
نویسندگان
چکیده
A precise determination of the charm-strange baryon Ξc lifetime is presented. The data were accumulated by the Fermilab high-energy photoproduction experiment FOCUS. The measurement is made with 300 Ξc → Ξ −π+π+ decays, 130 Ξc → Σ+K−π+ decays, 45 Ξc → pK −π+ decays and 58 Ξc → Λ 0K−π+π+ decays. The Ξc lifetime is measured to be 0.439±0.022±0.009 ps.
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