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Charmonium production in p pbar annihilation: Estimating cross sections from decay widths

A. Lundborg·T. Barnes·U. Wiedner
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Abstract

The cross sections for the charmonium production processes p pbar -> m Psi, where m is a light meson and Psi is a charmonium state, are of great interest for the planned p-pbar experiment PANDA. In this paper we estimate these cross sections using known results for the decays Psi -> m p pbar which are related to these reactions by crossing. In lieu of detailed experimental data on the decay Dalitz plots, we assume a constant amplitude as a first approximation; this implies a simple relation between the cross sections and decay widths. The single measured exclusive cross section of this type is p pbar -> pi0 J/psi, which was reported by E760 to be 130 +/- 25 pb near sqrt(s) = 3.5-3.6 GeV. In comparison, our constant amplitude estimate is about 300 pb at this energy. This suggests that our approach is useful as a simple estimate, but should be refined through detailed modeling of resonances and other energy-dependent effects in the experimental Psi -> m p pbar Dalitz plots.

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A. Lundborg, T. Barnes, U. Wiedner. 2005-07-14. Charmonium production in p pbar annihilation: Estimating cross sections from decay widths. https://doi.org/10.1103/physrevd.73.096003

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