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arXiv · 0802.3833

Ghost contributions to charmonium production in polarized high-energy collisions

M. Klasen·B. A. Kniehl·L. N. Mihaila·M. Steinhauser
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Abstract

In a previous paper [Phys. Rev. D 68, 034017 (2003)], we investigated the inclusive production of prompt J/psi mesons in polarized hadron-hadron, photon-hadron, and photon-photon collisions in the factorization formalism of nonrelativistic quantum chromodynamics providing compact analytic results for the double longitudinal-spin asymmetry A_{LL}. For convenience, we adopted a simplified expression for the tensor product of the gluon polarization four-vector with its charge conjugate, at the expense of allowing for ghost and anti-ghosts to appear as external particles. While such ghost contributions cancel in the cross section asymmetry A_{LL} and thus were not listed in our previous paper, they do contribute to the absolute cross sections. For completeness and the reader's convenience, they are provided in this addendum.

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M. Klasen, B. A. Kniehl, L. N. Mihaila, M. Steinhauser. 2008-02-26. Ghost contributions to charmonium production in polarized high-energy collisions. https://doi.org/10.1103/physrevd.77.117501

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