Generic tests of CP-violation in high-$p_\text{T}$ multi-lepton signals at the LHC and beyond

TL;DR

This paper proposes a model-independent method to detect tree-level CP-violation in high-$p_T$ multi-lepton signals at the LHC, demonstrating potential observable asymmetries using TeV-scale 4-fermion operators.

Contribution

It introduces a modified expression for CP-violation in non-self-conjugate initial states and a generic search strategy applicable to various models.

Findings

Potential for ${ m O}(10 ext{ extperthousand})$ CP asymmetries at the LHC

Method applicable to inclusive multi-lepton signals

Illustrative example with TeV-scale 4-fermion operators

Abstract

We introduce a modification to the standard expression for tree-level CP-violation in scattering processes at the LHC, which is important when the initial state in not self-conjugate. Based on that, we propose a generic and model-independent search strategy for probing tree-level CP-violation in inclusive multi-lepton signals. We then use TeV-scale 4-fermion operators of the form $tu\ell\ell$ and $tc \ell \ell$ with complex Wilson coefficients as an illustrative example and show that it may generate ${\cal O}(10\%)$ CP asymmetries that should be accessible at the LHC with an integrated luminosity of ${\cal O}(1000)$ fb$^{-1}$.