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arXiv · 0706.2733

Ultrasoft contribution to quarkonium production and annihilation

M. Beneke·Y. Kiyo·A. A. Penin
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Abstract

We compute the third-order correction to electromagnetic S-wave quarkonium production and annihilation rates due to the emission and absorption of an ultrasoft gluon. Our result completes the analysis of the non-relativistic quarkonium bound-state dynamics in the next-to-next-to-next-to-leading order. The impact of the ultrasoft correction on the Upsilon(1S) leptonic width and the top quark-antiquark threshold production cross section is estimated.

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M. Beneke, Y. Kiyo, A. A. Penin. 2007-06-19. Ultrasoft contribution to quarkonium production and annihilation. https://doi.org/10.1016/j.physletb.2007.06.068

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