th / 0 21 10 65 v 1 2 1 N ov 2 00 2 1 Near - threshold ω - meson production in proton - proton collisions ∗ : With or without resonance excitations ?
نویسندگان
چکیده
We present results for the pp → ppω reaction studied by considering two different scenarios: with and without the inclusion of nucleon resonance excitations. The recently measured angular distribution by the COSY-TOF Collaboration at an excess energy of Q = 173 MeV and the energy dependence of the total cross section data for π−p → ωn are used to calibrate the model parameters. The inclusion of nucleon resonances improves the theoretical prediction for the energy dependence of the total cross section in pp → ppω at excess energies Q < 31 MeV. However, it still underestimates the data by about a factor of two, and remains a problem in understanding the reaction mechanism.
منابع مشابه
ar X iv : n uc l - th / 0 21 10 54 v 1 1 9 N ov 2 00 2 1 π and ρ loop corrections to ω photoproduction in the resonance region
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