Polarization as a Probe to the Production Mechanisms of Charmonium in $πN$ Collisions

W. -K. Tang; S. J. Brodsky; M. Vänttinen; P. Hoyer

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arXiv · hep-ph/9408371

Polarization as a Probe to the Production Mechanisms of Charmonium in $πN$ Collisions

W. -K. Tang·S. J. Brodsky·M. Vänttinen·P. Hoyer

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Abstract

Measurements of the polarization of $\jp$ produced in pion-nucleus collisions are in disagreement with leading twist QCD prediction where $\jp$ is observed to have negligible polarization whereas theory predicts substantial polarization. We argue that this discrepancy cannot be due to poorly known structure functions nor the relative production rates of $\jp$ and $χ_J$. The disagreement between theory and experiment suggests important higher twist corrections, as has earlier been surmised from the anomalous non-factorized nuclear $A$-dependence of the $\jp$ cross section.

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W. -K. Tang, S. J. Brodsky, M. Vänttinen, P. Hoyer. 1994-08-25. Polarization as a Probe to the Production Mechanisms of Charmonium in $πN$ Collisions. https://arxiv.org/abs/hep-ph/9408371

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