Electroweak phase transition in the economical 3-3-1 model

TL;DR

This paper analyzes the electroweak phase transition in the economical 3-3-1 model, revealing a two-step first-order transition with potential implications for baryogenesis due to strong deviations from thermal equilibrium.

Contribution

It demonstrates that the EWPT in the E331 model occurs as two sequential first-order transitions, influenced by new particles, and assesses their strengths for baryogenesis.

Findings

Two sequential first-order phase transitions identified.

Transition strengths depend on masses of new particles.

Potential for baryogenesis due to strong phase transitions.

Abstract

We consider the EWPT in the economical 3-3-1 (E331) model. Our analysis shows that the EWPT in the model is a sequence of two first-order phase transitions, $SU(3) \rightarrow SU(2)$ at the TeV scale and $SU(2) \rightarrow U(1)$ at the $100$ GeV scale. The EWPT $SU(3) \rightarrow SU(2)$ is triggered by the new bosons and the exotic quarks; its strength is about $1 - 13$ if the mass ranges of these new particles are $10^2 \,\mathrm{GeV} - 10^3 \,\mathrm{GeV}$. The EWPT $SU(2) \rightarrow U(1)$ is strengthened by only the new bosons; its strength is about $1 - 1.15$ if the mass parts of $H^0_1$, $H^\pm_2$ and $Y^\pm$ are in the ranges $10 \,\mathrm{GeV} - 10^2 \,\mathrm{GeV}$. The contributions of $H^0_1$ and $H^{\pm}_2$ to the strengths of both EWPTs may make them sufficiently strong to provide large deviations from thermal equilibrium and B violation necessary for baryogenesis.