ar X iv : h ep - p h / 06 01 20 7 v 1 2 5 Ja n 20 06 Heavy - Quark Form Factors and Threshold Cross Section at O ( α 2 S )
نویسنده
چکیده
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, QQ̄, 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− → QQ̄ cross section, and the forward-backward asymmetry of heavy quarks. Here the QQ̄ threshold cross section is presented with some new second order axial vector contributions.
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