Standard-Model Prediction of ε<sub>K</sub> with Manifest Quark-Mixing Unitarity

Brod, Joachim, Gorbahn, Martin and Stamou, Emmanuel (2020) Standard-Model Prediction of ε<sub>K</sub> with Manifest Quark-Mixing Unitarity. PHYSICAL REVIEW LETTERS, 125 (17). 171803-.

Text
paper.pdf - Author Accepted Manuscript
Download (492kB) | Preview

Official URL: http://dx.doi.org/10.1103/PhysRevLett.125.171803

Abstract

The parameter ε_{K} describes CP violation in the neutral kaon system and is one of the most sensitive probes of new physics. The large uncertainties related to the charm-quark contribution to ε_{K} have so far prevented a reliable standard-model prediction. We show that Cabibbo-Kobayashi-Maskawa unitarity enforces a unique form of the |ΔS=2| weak effective Lagrangian in which the short-distance theory uncertainty of the imaginary part is dramatically reduced. The uncertainty related to the charm-quark contribution is now at the percent level. We present the updated standard-model prediction ε_{K}=2.16(6)(8)(15)×10^{-3}, where the errors in parentheses correspond to QCD short-distance, long-distance, and parametric uncertainties, respectively.

Item Type:	Article
Additional Information:	5 pages, 1 figure
Uncontrolled Keywords:	hep-ph, hep-ph, hep-lat
Depositing User:	Symplectic Admin
Date Deposited:	13 Aug 2020 07:31
Last Modified:	06 Oct 2023 07:00
DOI:	10.1103/PhysRevLett.125.171803
Related URLs:	Author Publisher
URI:	https://livrepository.liverpool.ac.uk/id/eprint/3097355