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arXiv · hep-ph/0107144

The Threshold t-tbar Cross Section at NNLL Order

A. H. Hoang·A. V. Manohar·I. W. Stewart·T. Teubner
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Abstract

The total cross section for top quark pair production close to threshold in e+e- annihilation is investigated. Details are given about the calculation at next-to-next-to-leading logarithmic order. The summation of logarithms leads to a convergent expansion for the normalization of the cross section, and small residual dependence on the subtraction parameter nu. A detailed analysis of the residual nu dependence is carried out. A conservative estimate for the remaining uncertainty in the normalization of the total cross section from QCD effects is $\lesssim \pm 3%$. This makes precise extractions of the strong coupling and top width feasible, and further studies of electroweak effects mandatory.

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A. H. Hoang, A. V. Manohar, I. W. Stewart, T. Teubner. 2001-07-13. The Threshold t-tbar Cross Section at NNLL Order. https://doi.org/10.1103/physrevd.65.014014

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