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arXiv · hep-ph/0312302

Infrared regulators and SCETII

Christian W. Bauer·Matthew P. Dorsten·Michael P. Salem
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Abstract

We consider matching from SCETI, which includes ultrasoft and collinear particles, onto SCETII with soft and collinear particles at one loop. Keeping the external fermions off their mass shell does not regulate all IR divergences in both theories. We give a new prescription to regulate infrared divergences in SCET. Using this regulator, we show that soft and collinear modes in SCETII are sufficient to reproduce all the infrared divergences of SCETI. We explain the relationship between IR regulators and an additional mode proposed for SCETII.

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Christian W. Bauer, Matthew P. Dorsten, Michael P. Salem. 2004-02-02. Infrared regulators and SCETII. https://doi.org/10.1103/physrevd.69.114011

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