M ar 2 00 4 A Study of J / ψ → γγV ( ρ , φ ) Decays with the BESII Detector
نویسندگان
چکیده
Using a sample of 58× 106 J/ψ events collected with the BESII detector, radiative decays J/ψ → γγV , where V = ρ or φ, are studied. A resonance around 1420 MeV/c2 (X(1424)) is observed in the γρ mass spectrum. Its mass and width are measured to be 1424 ± 10 (stat) ± 11 (sys) MeV/c2 and 101.0 ± 8.8 ± 8.8 MeV/c2, respectively, and its branching ratio B(J/ψ → γX(1424) → γγρ) is determined to be (1.07± 0.17± 0.11)× 10−4. A search for X(1424) → γφ yields a 95% C.L. upper limit B(J/ψ → γX(1424) → γγφ) < 0.82 × 10−4.
منابع مشابه
2 00 4 A Study of J / ψ → γγV ( ρ , φ ) Decays with the BESII Detector
Using a sample of 58× 106 J/ψ events collected with the BESII detector, radiative decays J/ψ → γγV , where V = ρ or φ, are studied. A resonance around 1420 MeV/c2 (X(1424)) is observed in the γρ mass spectrum. Its mass and width are measured to be 1424 ± 10 (stat) ± 11 (sys) MeV/c2 and 101.0 ± 8.8 ± 8.8 MeV/c2, respectively, and its branching ratio B(J/ψ → γX(1424) → γγρ) is determined to be (1...
متن کاملA Study of J / ψ → γγV ( ρ , φ ) Decays with the BESII Detector
Using a sample of 58× 106 J/ψ events collected with the BESII detector, radiative decays J/ψ → γγV , where V = ρ or φ, are studied. A resonance around 1420 MeV/c2 (X(1424)) is observed in the γρ mass spectrum. Its mass and width are measured to be 1424 ± 10 (stat) ± 11 (sys) MeV/c2 and 101.0 ± 8.8 ± 8.8 MeV/c2, respectively, and its branching ratio B(J/ψ → γX(1424) → γγρ) is determined to be (1...
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