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Two-Loop QCD Corrections to the Heavy Quark Form Factors: Axial Vector Contributions

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

We consider the Z Q Qbar vertex to second order in the QCD coupling for an on-shell massive quark-antiquark pair and for arbitrary momentum transfer of the Z boson. We present closed analytic expressions for the two parity-violating form factors of that vertex at the two-loop level in QCD, excluding the contributions from triangle diagrams. These form factors are expressed in terms of 1-dimensional harmonic polylogarithms of maximum weight 4.

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W. Bernreuther, R. Bonciani, T. Gehrmann, R. Heinesch, T. Leineweber, P. Mastrolia, E. Remiddi. 2004-12-17. Two-Loop QCD Corrections to the Heavy Quark Form Factors: Axial Vector Contributions. https://doi.org/10.1016/j.nuclphysb.2005.01.035

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