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Recent Progress in One-Loop Multi-Parton Calculations

Z. Bern·L. Dixon·D. C. Dunbar·D. A. Kosower
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Abstract

We describe techniques that simplify the calculation of one-loop QCD amplitudes with many external legs, which are needed for next-to-leading-order (NLO) corrections to multi-jet processes. The constraints imposed by perturbative unitarity, collinear singularities and a supersymmetry-inspired organization of helicity amplitudes are particularly useful. Certain sequences of one-loop helicity amplitudes may be obtained for an arbitrary number of external gluons using these techniques. We also report on progress in completing the set of one-loop helicity amplitudes required for NLO three-jet production at hadron colliders, namely the amplitudes with two external quarks and three gluons. (Contribution presented by L. Dixon at the workshop ``QCD'94'', Montpellier, France, July 7-13, 1994. To appear in those proceedings.)

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Z. Bern, L. Dixon, D. C. Dunbar, D. A. Kosower. 1994-09-02. Recent Progress in One-Loop Multi-Parton Calculations. https://doi.org/10.1016/0920-5632(95)00060-m

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