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arXiv · 1910.13407

On-shell constructibility of Born amplitudes in spontaneously broken gauge theories

Robert Franken·Christian Schwinn
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Abstract

We perform a comprehensive study of on-shell recursion relations for Born amplitudes in spontaneously broken gauge theories and identify the minimal shifts required to construct amplitudes with a given particle content and spin quantum numbers. We show that two-line or three-line shifts are sufficient to construct all amplitudes with five or more particles, apart from amplitudes involving longitudinal vector bosons or scalars, which may require at most five-line shifts. As an application, we revisit selection rules for multi-boson amplitudes using on-shell recursion and little-group transformations.

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Robert Franken, Christian Schwinn. 2019-10-29. On-shell constructibility of Born amplitudes in spontaneously broken gauge theories. https://doi.org/10.1007/jhep02(2020)073

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