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Theoretical status of epsilon'/epsilon

Matthias Jamin
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Abstract

The present theoretical status of the parameter for direct CP violation epsilon'/epsilon in the Standard Model is reviewed and compared with most recent experimental measurements of the same quantity. After collecting the basic expressions for epsilon'/epsilon, the situation of hadronic matrix element calculations is summarised. The matrix elements constitute the dominant source of uncertainty for theoretical determinations of epsilon'/epsilon. For central values of the input parameters, the numerical analysis then yields results which are generally below the experimental data. Possible reasons for these findings are discussed.

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Matthias Jamin. 1999-11-17. Theoretical status of epsilon'/epsilon. https://arxiv.org/abs/hep-ph/9911390

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