학술논문

Towards NNLO accuracy for $\varepsilon'/\varepsilon$
Document Type
Working Paper
Source
Subject
High Energy Physics - Phenomenology
Language
Abstract
The quantity $\varepsilon'/\varepsilon$ measures direct CP violation in Kaon decays. Recent SM predictions show a $2.9\sigma$ tension with data, with the theoretical uncertainty dominating. As rapid progress on the lattice is bringing nonperturbative long-distance effects under control, a more precise knowledge of short-distance contributions is needed. We describe the first NNLO results for $\varepsilon'/\varepsilon$ and discuss future prospects, as well as issues of scheme dependence and the separation of perturbative and nonperturbative effects. Finally we also comment on the solution of the renormalisation-group evolution in one of the talks at this conference and present the correct solution.
Comment: 8 pages, Proceedings of the Kaon 2016 Conference