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arXiv · hep-ph/0205289

Power Counting in the Soft-Collinear Effective Theory

Christian W. Bauer·Dan Pirjol·Iain W. Stewart
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Abstract

We describe in some detail the derivation of a power counting formula for the soft-collinear effective theory (SCET). This formula constrains which operators are required to correctly describe the infrared at any order in the Lambda_QCD/Q expansion (lambda expansion). The result assigns a unique lambda-dimension to graphs in SCET solely from vertices, is gauge independent, and can be applied independent of the process. For processes with an OPE the lambda-dimension has a correspondence with dynamical twist.

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Christian W. Bauer, Dan Pirjol, Iain W. Stewart. 2002-08-16. Power Counting in the Soft-Collinear Effective Theory. https://doi.org/10.1103/physrevd.66.054005

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