Λ ( 1520 ) production in Z decays
نویسندگان
چکیده
Preliminary DELPHI results from two analyses are presented: 1. Λ(1520) production in Z0→qq, 2. Inclusive ρ, f0(980), f2(1270), K ∗0 2 (1430) and f ′ 2(1525) production in Z 0→ qq. Both analyses are based on about 2 million multihadronic events collected in 1994 and 1995, using the particle identification capabilities of the DELPHI Ring Imaging Cherenkov detectors and measured ionisation losses in the Time Projection Chamber. The total production rates per hadronic Z decay have been determined to be: 0.030±0.006 for Λ(1520), 1.19±0.10 for ρ, 0.164±0.021 for f0(980), 0.214±0.032 for f2(1270), 0.073± 0.023 for K∗0 2 (1430) and 0.012± 0.006 for f ′ 2(1525). The production rates and differential cross-sections are compared with the results of other LEP experiments and with model expectations. The mass dependence of meson production is investigated quantitatively whereas the origin of Λ(1520) production is investigated qualitatively.
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