CP violation in charged Higgs production and decays in the Complex Two Higgs Doublet Model

TL;DR

This paper investigates CP violation effects in charged Higgs production and decay processes at the LHC within the complex Two Higgs Doublet Model, providing detailed calculations of asymmetries and their numerical analysis.

Contribution

It introduces a comprehensive calculation of CP violating asymmetries in charged Higgs processes in the complex 2HDM using automated tools, with detailed implementation and comparison to MSSM results.

Findings

CP asymmetries are smaller than in MSSM, not exceeding 2-3%.

Detailed numerical analysis of CP violation effects in charged Higgs processes.

Implementation of complex 2HDM in FeynArts and FormCalc.

Abstract

We study the effects of CP violation in charged Higgs boson production $pp\to t H^\pm + X$ at the LHC, as well as in the charged Higgs boson decays $H^\pm \to t b$ and $H^\pm \to W^\pm H_i^0$, $i=1,2,3$. The study is done in the framework of the type II complex Two Higgs Doublet Model (2HDM) with softly broken $Z_2$ symmetry. In this model violation of CP invariance is induced by the complex parameter $m^2_{12}$ of the tree-level Higgs potential. We calculate the CP violating rate asymmetries for $H^+$ and $H^-$ production and decays as well as for the combined processes at one-loop level and perform a detailed numerical analysis. All calculations are done with the automatic amplitude generator FeynArts and the calculational tool FormCalc, for which we have written a complete complex 2HDM model file and relevant fortran drivers. The implementation of the complex 2HDM in FeynArts and FormCalc is described. In comparison with the analogous results in the MSSM, all considered CP violating asymmetries are smaller by an order of magnitude and do not exceed 2 to 3%.