On the Dimensional Regularization of QCD Helicity Amplitudes With Quarks

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.

arXiv commentSome minor changes regarding the presentation of the relation to the FDF approach

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Cited by in corpus (6)

• Analytic Form of the Planar Two-Loop Five-Parton Scattering Amplitudes in QCD
• Planar Two-Loop Five-Parton Amplitudes from Numerical Unitarity
• Leading-Color Two-Loop Amplitudes for Four Partons and a W Boson in QCD
• Two-Loop QCD Corrections for Three-Photon Production at Hadron Colliders
• Fermion Traces Without Evanescence
• Complete Form Factors in Yang-Mills from Unitarity and Spinor Helicity in Six Dimensions