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Near-threshold $ω$-meson production in proton-proton collisions: With or without resonance excitations ?

K. Tsushima·K. Nakayama
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Abstract

We present results for the $p p \to p p ω$ 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 $π^- p \to ωn$ 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 $pp \to ppω$ 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.

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K. Tsushima, K. Nakayama. 2002-12-12. Near-threshold $ω$-meson production in proton-proton collisions: With or without resonance excitations ?. https://doi.org/10.1016/s0375-9474(03)01140-0

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