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arXiv · hep-ph/9701353

Annihilation of S-wave quarkonia and the measurement of alpha_s

Martin Gremm·Anton Kapustin
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Abstract

We analyze the relativistic corrections to annihilation rates of S-wave quarkonia within the framework of NRQCD. We show that order v^2 corrections can be expressed in terms of the heavy quark pole mass and the quarkonium mass. The ratio of hadronic to radiative annihilation rates for eta_b and eta_c can therefore be predicted accurately. The contributions of color-octet operators to the hadronic decay rates of spin-triplet quarkonia are shown to be significant, even though they arise at order v^4 in the velocity expansion. We provide a rough estimate of the color-octet contributions and extract the value of alpha_s from the experimental data on Upsilon decays.

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Martin Gremm, Anton Kapustin. 1997-04-16. Annihilation of S-wave quarkonia and the measurement of alpha_s. https://doi.org/10.1016/s0370-2693(97)00744-2

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