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Quarkonium Formation Time in a Model-Independent Approach

D. Kharzeev·R. L. Thews
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Abstract

We use dispersion relations to reconstruct, in a model-independent way, the formation dynamics of heavy quarkonium from the experimental data on e+ e- annihilation to Q-bar Q. We extract a distribution of formation times with a mean value for the J/psi, tau{J/psi} = 0.44 fm; and for the Upsilon, tau{Upsilon} = 0.32 fm. The corresponding widths of these distributions are given by Delta-tau{J/psi} = 0.31 fm and Delta-tau{Upsilon} = 0.28 fm. This information can be used as an input in modeling of heavy quarkonium production on nuclear targets.

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D. Kharzeev, R. L. Thews. 1999-07-06. Quarkonium Formation Time in a Model-Independent Approach. https://doi.org/10.1103/physrevc.60.041901

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