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arXiv · 1802.06730

Helicity amplitudes for QCD with massive quarks

Alexander Ochirov
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Abstract

The novel massive spinor-helicity formalism of Arkani-Hamed, Huang and Huang provides an elegant way to calculate scattering amplitudes in quantum chromodynamics for arbitrary quark spin projections. In this note we compute two families of tree-level QCD amplitudes with one massive quark pair and n-2 gluons. The two cases include all gluons with identical helicity and one opposite-helicity gluon being color-adjacent to one of the quarks. Our results naturally incorporate the previously known amplitudes for both quark spins quantized along one of the gluonic momenta. In the all-multiplicity formulae presented here the spin quantization axes can be tuned at will, which includes the case of the definite-helicity quark states.

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Alexander Ochirov. 2018-12-16. Helicity amplitudes for QCD with massive quarks. https://doi.org/10.1007/jhep04(2018)089

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