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Two-Loop Sudakov Form Factor in a Theory with Mass Gap

Bernd Feucht·Johann H. Kühn·Alexander A. Penin·Vladimir A. Smirnov
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Abstract

The two-loop Sudakov form factor is computed in a U(1) model with a massive gauge boson and a $U(1)\times U(1)$ model with mass gap. We analyze the result in the context of hard and infrared evolution equations and establish a matching procedure which relates the theories with and without mass gap setting the stage for the complete calculation of the dominant two-loop corrections to electroweak processes at high energy.

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Bernd Feucht, Johann H. Kühn, Alexander A. Penin, Vladimir A. Smirnov. 2005-04-14. Two-Loop Sudakov Form Factor in a Theory with Mass Gap. https://doi.org/10.1103/physrevlett.93.101802

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