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The Two-loop Soft Anomalous Dimension Matrix and Resummation at Next-to-next-to Leading Pole

S. Mert Aybat·Lance J. Dixon·George Sterman
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Abstract

We extend the resummation of dimensionally-regulated amplitudes to next-to-next-to-leading poles. This requires the calculation of two-loop anomalous dimension matrices for color mixing through soft gluon exchange. Remarkably, we find that they are proportional to the corresponding one-loop matrices. Using the color generator notation, we reproduce the two-loop single-pole quantities H^(2) introduced by Catani for quark and gluon elastic scattering. Our results also make possible threshold and a variety of other resummations at next-to-next-to leading logarithm. All of these considerations apply to 2 to n processes with massless external lines.

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S. Mert Aybat, Lance J. Dixon, George Sterman. 2006-07-27. The Two-loop Soft Anomalous Dimension Matrix and Resummation at Next-to-next-to Leading Pole. https://doi.org/10.1103/physrevd.74.074004

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