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arXiv · hep-ph/9805338

Hard exclusive $J/ψ$ leptoproduction on polarized targets

M. Vänttinen·L. Mankiewicz
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Abstract

We consider the exclusive production of $J/ψ$ mesons in polarized virtual-photon--proton collisions. We derive helicity amplitudes for the dominant subprocess $γ^* g \to J/ψg$ and show that polarization asymmetries vanish in the case of collinear scattering. Thus, contrary to what has been suggested earlier, this process is not a good probe of the polarized gluon distribution $Δg(x,Q^2)$ of the proton.

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M. Vänttinen, L. Mankiewicz. 1998-06-16. Hard exclusive $J/ψ$ leptoproduction on polarized targets. https://doi.org/10.1016/s0370-2693(98)00755-2

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