English

The CKM parameters in the SMEFT

High Energy Physics - Phenomenology 2019-06-05 v3 High Energy Physics - Experiment

Abstract

The extraction of the Cabibbo-Kobayashi-Maskawa (CKM) matrix from flavour observables can be affected by physics beyond the Standard Model (SM). We provide a general roadmap to take this into account, which we apply to the case of the Standard Model Effective Field Theory (SMEFT). We choose a set of four input observables that determine the four Wolfenstein parameters, and discuss how the effects of dimension-six operators can be included in their definition. We provide numerical values and confidence intervals for the CKM parameters, and compare them with the results of CKM fits obtained in the SM context. Our approach allows one to perform general SMEFT analyses in a consistent fashion, independently of any assumptions about the way new physics affects flavour observables. We discuss a few examples illustrating how our approach can be implemented in practice.

Keywords

Cite

@article{arxiv.1812.08163,
  title  = {The CKM parameters in the SMEFT},
  author = {Sébastien Descotes-Genon and Adam Falkowski and Marco Fedele and Martín González-Alonso and Javier Virto},
  journal= {arXiv preprint arXiv:1812.08163},
  year   = {2019}
}

Comments

36 pages. Version published in JHEP

R2 v1 2026-06-23T06:49:37.576Z