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arXiv · 1104.1418

$O(\alpha_s v^2)$ correction to pseudoscalar quarkonium decay to two photons

Yu Jia·Xiu-Ting Yang·Wen-Long Sang·Jia Xu
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Abstract

We investigate the $O(\alpha_s v^2)$ correction to the process of pseudoscalar quarkonium decay to two photons in nonrelativistic QCD (NRQCD) factorization framework. The short-distance coefficient associated with the relative-order $v^2$ NRQCD matrix element is determined to next-to-leading order in $\alpha_s$ through the perturbative matching procedure. Some technical subtleties encountered in calculating the ${O(\alpha_s)$ QCD amplitude are thoroughly addressed.

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Yu Jia, Xiu-Ting Yang, Wen-Long Sang, Jia Xu. 2011-04-07. $O(\alpha_s v^2)$ correction to pseudoscalar quarkonium decay to two photons. https://doi.org/10.1007/jhep06(2011)097

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