CP violation at one loop in the polarization-independent chargino production in e+e- collisions

TL;DR

This paper provides a comprehensive one-loop analysis of CP violation effects in unpolarized chargino pair production at e+e- colliders, highlighting the importance of vertex and self-energy contributions and their dependence on SUSY phases.

Contribution

It offers the first complete one-loop calculation of CP-odd effects in chargino production, emphasizing the significance of previously neglected contributions and phase sensitivities.

Findings

CP asymmetries are generated at one-loop in unpolarized e+e- collisions.

Vertex and self-energy contributions can dominate the CP-violating effects.

CP asymmetries depend on the phases of mu and A_t parameters.

Abstract

Recently Osland and Vereshagin noticed, based on sample calculations of some box diagrams, that in unpolarised e+e- collisions CP-odd effects in the non-diagonal chargino-pair production process are generated at one-loop. Here we perform a full one-loop analysis of these effects and point out that in some cases the neglected vertex and self-energy contributions may play a dominant role. We also show that CP asymmetries in chargino production are sensitive not only to the phase of mu parameter in the chargino sector but also to the phase of stop trilinear coupling A_t.