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arXiv · hep-ph/0103259

The NNLO tau+tau- Production Cross Section Close to Threshold

P. Ruiz-Femenia·A. Pich
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Abstract

The threshold behaviour of the cross section sigma(e+e+ -> tau+tau-) is analysed, taking into account the known higher-order corrections. At present, this observable can be determined to next-to-next-to-leading order (NNLO) in a combined expansion in powers of alpha_s and fermion velocities.

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P. Ruiz-Femenia, A. Pich. 2001-03-23. The NNLO tau+tau- Production Cross Section Close to Threshold. https://doi.org/10.1103/physrevd.64.053001

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