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arXiv · hep-ph/9608433

Colour-octet Contributions to $x_F$ Distributions in $J/ψ$ Hadro-production at Fixed Target Energies

Sourendu Gupta·K. Sridhar
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Abstract

We study J/ψproduction at fixed-target energies, including the colour-octet production mechanisms predicted by NRQCD. In an earlier paper, we found that the octet components were crucial in understanding p_T-integrated forward (x_F > 0) cross-sections. Here we make a detailed comparison of the theoretical predictions with measured x_F distributions from fixed-target experiments. We find that the model predictions agree well with data. Taking into account higher orders in NRQCD, we argue that sigma(chi_1)/sigma(chi_2)=0.6, in excellent agreement with data. Similiar arguments also predict that sigma(chi)/sigma(J/psi) is roughly equal in photo- and hadro-production.

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Sourendu Gupta, K. Sridhar. 1996-09-09. Colour-octet Contributions to $x_F$ Distributions in $J/ψ$ Hadro-production at Fixed Target Energies. https://doi.org/10.1103/physrevd.55.2650

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