6533b7d9fe1ef96bd126ce7a

RESEARCH PRODUCT

Theoretical status of $\varepsilon'/\varepsilon$

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description

We briefly overview the historical controversy around Standard Model predictions of $\varepsilon'/\varepsilon$ and clarify the underlying physics. A full update of this important observable is presented, with all known short- and long-distance contributions, including isospin-breaking corrections. The current Standard Model prediction, $\mathrm{Re}(\varepsilon'/\varepsilon) = (14\pm 5)\cdot 10^{-4}$, is in excellent agreement with the experimentally measured value.