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arXiv · hep-ph/9601349

Colour-octet Contributions to J/psi Hadroproduction at Fixed Target Energies

Sourendu Gupta·K. Sridhar
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Abstract

We investigate the integrated cross section for forward $\jpsi$ production in proton-proton and pion-proton collisions at centre of mass energies upto 60 GeV. We find that colour-octet contributions to the cross section are crucially important, and their inclusion produces a very good description of the data. Since the values of non-perturbative matrix elements are fixed by other experiments, these predictions are parameter-free.

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Sourendu Gupta, K. Sridhar. 1996-01-31. Colour-octet Contributions to J/psi Hadroproduction at Fixed Target Energies. https://doi.org/10.1103/physrevd.54.5545

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