Perturbative Higgs CP violation, unitarity and phenomenology

TL;DR

This paper explores how unitarity and probability conservation constrain CP-violating interactions of the Higgs boson, providing predictions for collider searches to detect or limit such CP violation.

Contribution

It combines unitarity constraints with experimental Higgs data to make concrete predictions about CP violation effects in collider phenomenology.

Findings

CP violation in Higgs sector can be constrained by unitarity.

Predictions for collider signatures of CP violation.

Correlation between Higgs signal strength and CP-violating effects.

Abstract

Perturbative probability conservation provides a strong constraint on the presence of new interactions of the Higgs boson. In this work we consider CP violating Higgs interactions in conjunction with unitarity constraints in the gauge-Higgs and fermion-Higgs sectors. Injecting signal strength measurements of the recently discovered Higgs boson allows us to make concrete and correlated predictions of how CP-violation in the Higgs sector can be directly constrained through collider searches for either characteristic new states or tell-tale enhancements in multi-Higgs processes.