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Reliability of a high energy one-loop expansion of e+e- --> W+W- in the SM and in the MSSM

Matteo Beccaria·Fernand M. Renard·Claudio Verzegnassi
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Abstract

We compare the logarithmic Sudakov expansions of the process e+e- --> W+W- in the one-loop approximation and in the resummed version, to subleading order accuracy, in the SM case and in a light SUSY scenario for the MSSM. We show that the two expansions are essentially identical below 1 TeV, but differ drastically at higher (2,3 TeV) center of mass energies. Starting from these conclusions, we argue that a complete one-loop calculation in the energy region below 1 TeV does not seem to need extra two-loop corrections, in spite of the relatively large size of the one-loop effects.

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Matteo Beccaria, Fernand M. Renard, Claudio Verzegnassi. 2003-04-17. Reliability of a high energy one-loop expansion of e+e- --> W+W- in the SM and in the MSSM. https://doi.org/10.1016/s0550-3213(03)00413-9

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