Radiative corrections to the $\rm S, T, U$ parameters and their impact on the $W$ boson mass in the 331 model

Abstract

We investigate radiative corrections to electroweak precision observables, specifically the Peskin--Takeuchi parameters $\mathrm{S}$, $\mathrm{T}$, and $\mathrm{U}$, in the $SU(3)_C \times SU(3)_L \times U(1)_X$ (331) model with $\beta = -\sqrt{3}$. Using the SARAH and SPheno packages, we compute the mass spectrum and low-energy observables. We show that these parameters place strong constraints on the model, requiring most of the scalar masses to lie in the TeV range or below, and imposing indirect bounds on the newly predicted gauge bosons. Furthermore, we demonstrate that the model can accommodate the $W$ boson mass anomaly reported by the CDF collaboration, should future measurements confirm its persistence.