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Relativistic corrections to gluon fragmentation into spin-triplet S-wave quarkonium

Geoffrey T. Bodwin·Jungil Lee
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Abstract

We use the NRQCD factorization formalism to calculate the relativistic corrections to the fragmentation function for a gluon fragmenting into a spin-triplet S-wave heavy quarkonium. We make use of the gauge-invariant formulation of the fragmentation function of Collins and Soper. The color-octet contribution receives a large, negative relativistic correction, while the color-singlet contribution receives a large, positive relativistic correction. The considerable decrease in the color-octet contribution requires a corresponding increase in the phenomenological value of the leading color-octet matrix element in order to maintain a fit to the Fermilab Tevatron data.

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Geoffrey T. Bodwin, Jungil Lee. 2004-01-23. Relativistic corrections to gluon fragmentation into spin-triplet S-wave quarkonium. https://doi.org/10.1103/physrevd.69.054003

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