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arXiv · 1609.06206

Coupling WW, ZZ unitarized amplitudes to $γγ$ in the TeV region

Rafael L. Delgado·Antonio Dobado·Felipe J. Llanes-Estrada
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Abstract

We define and calculate helicity partial-wave amplitudes for processes linking the Electroweak Symmetry Breaking Sector (EWSBS) to $γγ$, employing (to NLO) the Higgs-EFT (HEFT) extension of the Standard Model and the Equivalence Theorem, while neglecting all particle masses. The resulting amplitudes can be useful in the energy regime ($500\,{\rm GeV}-3\,{\rm TeV}$). We also deal with their unitarization so that resonances of the EWSBS can simultaneously be described in the $γγ$ initial or final states. Our resulting amplitudes satisfy unitarity, perturbatively in $α$, but for all $s$ values. In this way we improve on the HEFT that fails as interactions become stronger with growing $s$ and provide a natural framework for the decay of dynamically generated resonances into $WW$, $ZZ$ and $γγ$ pairs.

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Rafael L. Delgado, Antonio Dobado, Felipe J. Llanes-Estrada. 2016-09-20. Coupling WW, ZZ unitarized amplitudes to $γγ$ in the TeV region. https://doi.org/10.1140/epjc%2Fs10052-017-4768-y

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