High-temperature electroweak symmetry breaking by SM twins
Oleksii Matsedonskyi
Abstract
A bstract We analyse a possible adjustment of Twin Higgs models allowing to have broken electroweak (EW) symmetry at all temperatures below the sigma-model scale ∼ 1 TeV. The modification consists of increasing the Yukawa couplings of the twins of light SM fermions. The naturalness considerations then imply a presence of relatively light electroweak-charged fermions, which can be produced at the LHC, and decay into SM gauge and Higgs bosons and missing energy. Analysis of experimental bounds shows that such a modified model features an increased amount of fine-tuning compared to the original Twin Higgs models, but still less tuning than the usual pseudo-Nambu-Goldstone Higgs models not improved by Z 2 twin symmetry. The obtained modification in the evolution of the EW symmetry breaking strength can, in particular, have interesting implications for models of EW baryogenesis, which we comment on.