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arXiv · 0905.1137

The QCD form factor of heavy quarks at NNLO

J. Gluza·A. Mitov·S. Moch·T. Riemann
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Abstract

We present an analytical calculation of the two-loop QCD corrections to the electromagnetic form factor of heavy quarks. The two-loop contributions to the form factor are reduced to linear combinations of master integrals, which are computed through higher orders in the parameter of dimensional regularization epsilon=(4-D)/2. Our result includes all terms of order epsilon at two loops and extends the previous literature. We apply the exponentiation of the heavy-quark form factor to derive new improved three-loop expansions in the high-energy limit. We also discuss the implications for predictions of massive n-parton amplitudes based on massless results in the limit, where the quark mass is small compared to all kinematical invariants.

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J. Gluza, A. Mitov, S. Moch, T. Riemann. 2009-05-07. The QCD form factor of heavy quarks at NNLO. https://doi.org/10.1088/1126-6708%2F2009%2F07%2F001

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