CP-sensitive spin-spin correlations in neutralino production at the ILC

TL;DR

This paper investigates CP-violating effects in neutralino pair production at the ILC, focusing on spin correlations and their impact on observable asymmetries, within the framework of the MSSM with complex parameters.

Contribution

It introduces a detailed analysis of CP-sensitive spin-spin correlations and their observables in neutralino production, considering neutralino polarization effects.

Findings

CP-sensitive observables can be significantly affected by neutralino polarization.

The study provides numerical predictions for cross sections and branching ratios in the MSSM.

T-odd products of spin-spin terms serve as effective CP-violation indicators.

Abstract

We study the CP-violating terms of the spin-spin correlations in neutralino production and their subsequent two-body decays into sleptons plus leptons at the ILC. We analyze CP-sensitive observables with the help of T-odd products of the spin-spin terms. These terms depend on the polarizations of both neutralinos, with one polarization perpendicular to the production plane. We present a detailed numerical study of the CP-sensitive observables, cross sections, and neutralino branching ratios in the Minimal Supersymmetric Standard Model with complex parameters.