Search for promptly produced heavy quarkonium states in hadronic Z decays
A search has been made for direct production of heavy quarkonium states in more than 3 million hadronic Z 0 decays in the 1991-1994 DELPHI data. Prompt J/ψ, ψ(2 S) and Γ candidates have been searched for through their leptonic decay modes using criteria based on the kinematics and decay vertex posit...
| Những tác giả chính: | , , , , , , , , , , , , , , , , , , , , , , , , |
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| Định dạng: | Journal article |
| Ngôn ngữ: | English |
| Được phát hành: |
1995
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| Tóm tắt: | A search has been made for direct production of heavy quarkonium states in more than 3 million hadronic Z 0 decays in the 1991-1994 DELPHI data. Prompt J/ψ, ψ(2 S) and Γ candidates have been searched for through their leptonic decay modes using criteria based on the kinematics and decay vertex positions. New upper limits are set at the 90% confidence level for Br(Z 0→(Qq)X)/Br(Z 0→ hadrons) for various strong production mechanisms of J/ψ and Γ; these range down to 0.9×10-4. The limits are set in the presence of a small excess (∼1% statistical probability of a background fluctuation) in the sum of candidates from prompt J/ψ, ψ(2 S), γ(1 S), γ(2 S) and γ(3 S) relative to the estimated background. © 1996 Springer-Verlag. |
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