Constraining General 2HDM by the Evolution of Yukawa Couplings

TL;DR

This paper investigates how the evolution of Yukawa couplings in general 2HDM constrains model parameters, especially regarding flavor-changing neutral currents and the breaking of $Z_2$ symmetry, using renormalization group analysis.

Contribution

It provides a novel analysis of Yukawa coupling evolution to set bounds on $Z_2$ symmetry breaking in general 2HDM models.

Findings

Off-diagonal Yukawa couplings can induce flavor-changing neutral currents.

Landau poles and large Yukawa couplings impose constraints on model parameters.

The study quantifies the extent of $Z_2$ symmetry breaking allowed in 2HDM.

Abstract

We analysis the constraints of the general two Higgs doublet models via evolving the Yukawa coupling constants to high energy under renormalization group. We consider the appearance of a Landau pole or large off-diagonal Yukawa couplings which cause tree level flavour changing neutral currents. Our study shows the latter condition can be used to answer that how much $Z_2$ symmetry breaking can be allowed in a given 2HDM model.