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arXiv · hep-ph/9305260

Heavy Quark Fragmentation to Polarised Quarkonium

Adam F. Falk·Michael Luke·Martin J. Savage·Mark B. Wise
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Abstract

We calculate the polarisation of $ψ$'s and $Υ$'s produced by the fragmentation of heavy quarks. We find that fragmentation to transversely aligned quarkonium is slightly enhanced relative to longitudinally polarised. This net alignment corresponds to a $\sim 5\%$ asymmetry in the angular distribution of leptons produced in the subsequent decay of the quarkonium. We point out that the leading gluon contribution to $ψ$ and $Υ$ production arises from the evolution of the charm quark fragmentation function, rather than from direct gluon fragmentation.

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Adam F. Falk, Michael Luke, Martin J. Savage, Mark B. Wise. 1993-05-13. Heavy Quark Fragmentation to Polarised Quarkonium. https://doi.org/10.1016/0370-2693(93)90986-r

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