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Radiative corrections to pair production of unstable particles: results for e^+e^- --> 4 fermions

W. Beenakker·F. A. Berends·A. P. Chapovsky
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Abstract

Radiative corrections to processes that involve the production and subsequent decay of unstable particles are complex due to various theoretical and practical problems. The so-called double-pole approximation offers a way out of these problems. This method is applied to the reaction $e^{+}e^{-} \to W^{+}W^{-} \to 4 $fermions, which allows us to address all the key issues of dealing with unstable particles, like gauge invariance, interactions between different stages of the reaction, and overlapping resonances. Within the double-pole approximation the complete $\OO(α)$ electroweak corrections are evaluated for this off-shell $W$-pair production process. Examples of the effect of these corrections on a number of distributions are presented. These comprise mass and angular distributions as well as the photon-energy spectrum.

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W. Beenakker, F. A. Berends, A. P. Chapovsky. 1998-11-26. Radiative corrections to pair production of unstable particles: results for e^+e^- --> 4 fermions. https://doi.org/10.1016/s0550-3213(99)00110-8

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