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Heavy-Quark Form Factors and Threshold Cross Section at O(α_S^2)

W. Bernreuther·R. Bonciani·T. Gehrmann·R. Heinesch·T. Leineweber·P. Mastrolia·E. Remiddi
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Abstract

During the last year, analytic expressions for the two-loop QCD corrections to the form factors for the vector, axial-vector, scalar and pseudo-scalar vertices involving a pair of heavy quarks, $Q \bar{Q}$, were calculated. The results are valid for arbitrary momentum transfer and mass of the heavy quarks. These form factors have a number of applications, including anomalous couplings, the $e^{+}e^{-} \to Q \bar Q$ cross section, and the forward-backward asymmetry of heavy quarks. Here the $Q {\bar Q}$ threshold cross section is presented with some new second order axial vector contributions.

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W. Bernreuther, R. Bonciani, T. Gehrmann, R. Heinesch, T. Leineweber, P. Mastrolia, E. Remiddi. 2006-01-25. Heavy-Quark Form Factors and Threshold Cross Section at O(α_S^2). https://arxiv.org/abs/hep-ph/0601207

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