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arXiv · 1803.11127

On the Dimensional Regularization of QCD Helicity Amplitudes With Quarks

F. R. Anger·V. Sotnikov
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Abstract

We study QCD helicity amplitudes with an arbitrary number of (massive) quarks, keeping unobserved (loop) particles in fixed integer $D_s$ dimensions. We find a suitable embedding of external four-dimensional fermion states into higher dimensional spaces. This allows to identify the $D_s$ dependence of amplitudes with external quarks at one and two loops, permitting an analytic continuation in $D_s$. Explicitly we focus on 't Hooft-Veltman and four-dimensional helicity schemes for which we provide a compact prescription for the computation of one- and two-loop amplitudes amenable for numerical implementation.

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F. R. Anger, V. Sotnikov. 2018-03-29. On the Dimensional Regularization of QCD Helicity Amplitudes With Quarks. https://arxiv.org/abs/1803.11127

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