Momentum asymmetries as CP violating observables

TL;DR

This paper proposes momentum asymmetry observables to detect CP violation in three-body decays at hadron colliders, addressing challenges from incomplete kinematic information and various production mechanisms.

Contribution

It introduces novel momentum asymmetry observables suitable for collider experiments, accounting for missing information and different production scenarios.

Findings

Applicable to heavy neutralino decays in supersymmetry

Effective in heavy Majorana neutrino decay analysis

Addresses production mechanism complications

Abstract

Three body decays can exhibit CP violation that arises from interfering diagrams with different orderings of the final state particles. We construct several momentum asymmetry observables that are accessible in a hadron collider environment where some of the final state particles are not reconstructed and not all the kinematic information can be extracted. We discuss the complications that arise from the different possible production mechanisms of the decaying particle. Examples involving heavy neutralino decays in supersymmetric theories and heavy Majorana neutrino decays in Type-I seesaw models are examined.