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arXiv · 0710.1300

Massive Quark-Gluon Scattering Amplitudes at Tree Level

Anthony Hall
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Abstract

Results for four-, five-, and six-parton tree amplitudes for massive quark-antiquark scattering with gluons are calculated using the recursion relations of Britto, Cachazo, Feng, and Witten. The required diagrams are generated using shifts of the momenta of a pair of massless legs to complex values. Checks verifying the calculations are described, and a simple formula for the shifted spinors of an internal gluon is presented.

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Anthony Hall. 2007-10-08. Massive Quark-Gluon Scattering Amplitudes at Tree Level. https://doi.org/10.1103/physrevd.77.025011

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