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Diffractive $\jpsi$ production through Color-Octet mechanism at hadron colliders

Feng Yuan·Kuang-Ta Chao
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Abstract

We propose the color-octet mechanism combined with the two gluon exchange model for the diffractive $J/ψ$ production in hadron collisions. In the leading logarithmic approximation (LLA) in QCD, we find that the diffractive $J/ψ$ production rate is related to the off-diagonal gluon density in the proton and to the nonperturbative color-octet matrix element of $J/ψ$. The rate is found to be very sensitive to the gluon density at very small values of $x$ (down to $x=O(10^{-6})$). As a result, this process may provide a wide window for testing the two-gluon exchange model, and may be particularly useful in studying the small $x$ physics. And it may also be a golden place to test the color-octet mechanism proposed by solving the $ψ'(J/ψ)$ surplus problem at the Tevatron.

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Feng Yuan, Kuang-Ta Chao. 1998-07-10. Diffractive $\jpsi$ production through Color-Octet mechanism at hadron colliders. https://doi.org/10.1103/physrevd.58.114016

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