English

Update on $\varepsilon_K$ with lattice QCD inputs

High Energy Physics - Lattice 2018-04-18 v2

Abstract

We report updated results for εK\varepsilon_K, the indirect CP violation parameter in neutral kaons, which is evaluated directly from the standard model with lattice QCD inputs. We use lattice QCD inputs to fix BˉK\bar{B}_K, Vcb|V_{cb}|, ξ0\xi_0, ξ2\xi_2, Vus|V_{us}|, and mc(mc)m_c(m_c). Since Lattice 2016, the UTfit group has updated the Wolfenstein parameters in the angle-only-fit method, and the HFLAV group has also updated Vcb|V_{cb}|. Our results show that the evaluation of εK\varepsilon_K with exclusive Vcb|V_{cb}| (lattice QCD inputs) has 4.0σ4.0\sigma tension with the experimental value, while that with inclusive Vcb|V_{cb}| (heavy quark expansion based on OPE and QCD sum rules) shows no tension.

Keywords

Cite

@article{arxiv.1710.06614,
  title  = {Update on $\varepsilon_K$ with lattice QCD inputs},
  author = {Yong-Chull Jang and Weonjong Lee and Sunkyu Lee and Jaehoon Leem},
  journal= {arXiv preprint arXiv:1710.06614},
  year   = {2018}
}

Comments

8 pages, 7 figures, Lattice 2017 proceeding, references updated

R2 v1 2026-06-22T22:17:47.969Z