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arXiv · 2012.07758

Vacuum structure of the $\mathbb{Z}_2$ symmetric Georgi-Machacek model

Abstract

We discuss the vacuum structure of a version of the Georgi-Machecek model with an exact $\mathbb{Z}_2$ symmetry acting on the triplet fields. Besides the usual custodial-symmetric model, with $ρ=1$ at tree-level, a model with a dark matter candidate is also viable. The other phases of the model lead to electric charge breaking, a wrong pattern of electroweak symmetry breaking or to $ρ\neq 1$ at tree-level. We derive conditions to have an absolute minimum in each of the two viable phases, the custodial and the dark matter phases.

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Duarte Azevedo, Pedro M. Ferreira, Heather E. Logan, Rui Santos. 2020-12-14. Vacuum structure of the $\mathbb{Z}_2$ symmetric Georgi-Machacek model. https://doi.org/10.1007/jhep03(2021)221

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