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arXiv · 0806.3467

Masses, fermions and generalized D-dimensional unitarity

R. K. Ellis·W. T. Giele·Z. Kunszt·K. Melnikov
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Abstract

We extend the generalized D-dimensional unitarity method for numerical evaluation of one-loop amplitudes by incorporating massive particles. The issues related to extending the spinor algebra to higher dimensions, treatment of external self-energy diagrams and mass renormalization are discussed within the context of the D-dimensional unitarity method. To validate our approach, we calculate in QCD the one-loop scattering amplitudes of a massive quark pair with up to three additional gluons for arbitrary spin states of the external quarks and gluons.

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R. K. Ellis, W. T. Giele, Z. Kunszt, K. Melnikov. 2008-06-20. Masses, fermions and generalized D-dimensional unitarity. https://doi.org/10.1016/j.nuclphysb.2009.07.023

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