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arXiv · hep-ph/9912411

Two-Spin Asymmetry for $ψ^{\prime}$ Photoproduction with Color-Octet Mechanism

Kazutaka Sudoh·Toshiyuki Morii
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Abstract

We studied the photoproduction of $ψ^{\prime}$ in the forward regions in polarized $γp$ collisions at relevant HERA energies. We found that this reaction is very effective to test the color-octet mechanism which is based on the NRQCD factorization formalism. Furthermore we found that the value of the NRQCD matrix elements can be severely constrained by measuring the two-spin asymmetry, though the process depends on the polarized gluon distribution $Δg(x)$.

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Kazutaka Sudoh, Toshiyuki Morii. 2000-02-29. Two-Spin Asymmetry for $ψ^{\prime}$ Photoproduction with Color-Octet Mechanism. https://doi.org/10.1103/physrevd.62.057501

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