English

Current status of $\varepsilon_K$ calculated with lattice QCD inputs

High Energy Physics - Lattice 2014-11-13 v2 High Energy Physics - Phenomenology

Abstract

We present results for εK\varepsilon_K, the indirect CP violation parameter, calculated in the Standard Model using inputs from lattice QCD: the kaon bag parameter B^K\hat{B}_K, and the CKM matrix element VcbV_{cb} from the axial current form factor for the exclusive decay BˉDνˉ\bar{B}\to D^*\ell\bar{\nu} at zero-recoil. In addition, we take the coordinates of the unitarity triangle apex (ρˉ,ηˉ)(\bar{\rho},\bar{\eta}) from the angle-only fit of the UTfit Collaboration and use VusV_{us} to fix λ\lambda. In order to estimate the systematic error, we also use Wolfenstein parameters from the CKMfitter and UTfit. We find a 3.3(2)σ3.3(2)\sigma difference between εK\varepsilon_K and experiment with exclusive VcbV_{cb}. We report details of this preliminary result.

Keywords

Cite

@article{arxiv.1410.6995,
  title  = {Current status of $\varepsilon_K$ calculated with lattice QCD inputs},
  author = {Jon A. Bailey and Yong-Chull Jang and Weonjong Lee},
  journal= {arXiv preprint arXiv:1410.6995},
  year   = {2014}
}

Comments

7 pages, 4 figures, Lattice 2014 proceeding; PoS (LATTICE 2014) 371