Higgs Boson Masses in the Complex NMSSM at One-Loop Level

TL;DR

This paper computes one-loop corrections to neutral Higgs boson masses in the complex NMSSM, incorporating CP violation effects, to improve the precision of Higgs phenomenology predictions.

Contribution

It provides the first detailed calculation of one-loop Higgs masses in the complex NMSSM with CP violation, using a mixed renormalization scheme.

Findings

Significant effects of CP violation on Higgs masses.

Estimated theoretical error of about 10%.

Impact of radiative CP violation due to phase of $A_t$.

Abstract

The Next-to-Minimal Supersymmetric Extension of the Standard Model (NMSSM) with a Higgs sector containing five neutral and two charged Higgs bosons allows for a rich phenomenology. In addition, the plethora of parameters provides many sources of CP violation. In contrast to the Minimal Supersymmetric Extension, CP violation in the Higgs sector is already possible at tree-level. For a reliable understanding and interpretation of the experimental results of the Higgs boson search, and for a proper distinction of Higgs sectors provided by the Standard Model or possible extensions, the Higgs boson masses have to be known as precisely as possible including higher-order corrections. In this paper we calculate the one-loop corrections to the neutral Higgs boson masses in the complex NMSSM in a Feynman diagrammatic approach adopting a mixed renormalization scheme based on on-shell and $\bar{DR}$ conditions. We study various scenarios where we allow for tree-level CP-violating phases in the Higgs sector and where we also study radiatively induced CP violation due to a non-vanishing phase of the trilinear coupling $A_t$ in the stop sector. The effects on the Higgs boson phenomenology are found to be significant. We furthermore estimate the theoretical error due to unknown higher-order corrections by both varying the renormalization scheme of the top and bottom quark masses and by adopting different renormalization scales. The residual theoretical error can be estimated to about 10%.