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arXiv · hep-ph/0405236

Two-loop splitting functions in QCD

S. D. Badger·E. W. N. Glover
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Abstract

We present the universal two-loop splitting functions that describe the limits of two-loop $n$-point amplitudes of massless particles when two of the momenta are collinear. To derive the splitting amplitudes, we take the collinear limits of explicit two-loop four-point helicity amplitudes computed in the 't Hooft-Veltman scheme. The $g \to gg$ splitting amplitude has recently been computed using the unitarity sewing method and we find complete agreement with the results of Ref. \cite{Bern:2lsplit}. The two-loop $q \to qg$ and $g \to q\bar q$ splitting functions are new results. We also provide an expression for the two-loop soft splitting function.

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S. D. Badger, E. W. N. Glover. 2004-05-24. Two-loop splitting functions in QCD. https://doi.org/10.1088/1126-6708%2F2004%2F07%2F040

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