$ψ'$ Polarization as a test of colour octet quarkonium production

M. Beneke; I. Z. Rothstein

doi:10.1016/0370-2693(96)00030-5

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arXiv · hep-ph/9509375

$ψ'$ Polarization as a test of colour octet quarkonium production

M. Beneke·I. Z. Rothstein

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Abstract

We calculate the $α_s$ corrections to the transverse polarization fraction of $ψ^\prime$'s produced at the Tevatron. If the `$ψ^\prime$-anomaly' is explained by gluon fragmentation into a colour octet Fock component of the $ψ^\prime$, the $ψ^\prime$'s should be $100\%$ transversely polarized at leading order in $α_s$, up to spin symmetry breaking long-distance corrections. We find that the short-distance correction to the transverse polarization fraction is a few percent, so that a polarization measurement would provide a reliable test of the colour octet mechanism.

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M. Beneke, I. Z. Rothstein. 1995-09-24. $ψ'$ Polarization as a test of colour octet quarkonium production. https://doi.org/10.1016/0370-2693(96)00030-5

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