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arXiv · hep-ph/9210244

Zeros of Tree-Level Amplitudes at Multi-Boson Thresholds

M. B. Voloshin
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Abstract

Propagation of particles with emission of arbitrary number of identical bosons all being at rest is considered. It is shown that in certain models the tree-level amplitudes for production of $n$ scalar bosons by two incoming particles are all equal to zero at the threshold starting from some small number $n$. In particular this nullification occurs for production of massive scalars by two Goldstone bosons in the linear sigma model for $n > 1$ and also for production of Higgs bosons in the Standard Model by gauge bosons and/or by fermions, provided that the ratia of their masses to that of the Higgs boson take special discrete values.

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M. B. Voloshin. 1992-10-19. Zeros of Tree-Level Amplitudes at Multi-Boson Thresholds. https://doi.org/10.1103/physrevd.47.2573

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