Ядерна фізика та енергетика Nuclear Physics and Atomic Energy   ISSN: 1818-331X (Print), 2074-0565 (Online)   Publisher: Institute for Nuclear Research of the National Academy of Sciences of Ukraine   Languages: Ukrainian, English   Periodicity: 4 times per year   Open access peer reviewed journal

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Yu. V. Pylypchenko<sup>1

1</sup>University of Oslo, Oslo, Norway

Abstract: We report on the measurement of fraction of J/Ψ produced via radiative decays of χ_c mesons, R_χc, in collisions of 920 GeV protons with carbon nuclei. Analyzed data were collected by HERA-B detector in 2002 using di-muon trigger. The preliminary value is R_χc = 0.21 ± 0.06_stat ± 0.03_syst, for the events with -0.35 ≤ x_F(J/Ψ) ≤ 0.15.

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