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arXiv · 1211.1880

Selection rules for helicity amplitudes in massive gauge theories

Francesco Coradeschi·Paolo Lodone
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Abstract

After a rediscussion of the vanishing theorems for helicity amplitudes in unbroken gauge theories, we study the case of spontaneously broken gauge theories at high energy. The vanishing theorems generalize to a definite pattern of m/E-suppression of the amplitudes that vanish in the massless case, where E is the energy scale of the process and m is the mass of the gauge vectors. We use only elementary arguments, and as an application we show how these methods can be employed to understand some aspects of the effective W approximation in the polarized case.

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Francesco Coradeschi, Paolo Lodone. 2013-04-06. Selection rules for helicity amplitudes in massive gauge theories. https://doi.org/10.1103/physrevd.87.074026

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