Rescattering Effects for (\epsilon'/\epsilon)

TL;DR

This paper calculates hadronic matrix elements for K→ππ decays including rescattering effects, leading to a more stable and accurate prediction of the CP-violation parameter ('/) that aligns well with experimental data.

Contribution

It introduces a dispersion integral approach to include - rescattering effects in calculating '/, improving theoretical stability and agreement with experiments.

Findings

Enhanced stability of '/ predictions across matching scales

Good agreement with experimental measurements of '/

Demonstrated importance of rescattering effects in CP-violation calculations

Abstract

A calculation of the hadronic matrix elements for K\to\pi\pi including \pi-\pi rescattering effects in a dispersion integral is presented. I study the dependence of the results on the matching scale \mu and use them to calculate the CP-parameter (\epsilon\prime/\epsilon). I find improved stability on the matching scale and good agreement with the experimental results.