𝐷0− ¯ 𝐷 0 mixing in the Dyson-Schwinger approach

Abstract

In view of difficulty to reproduce observables in the 𝐷0 − ¯ 𝐷 0 mixing via the operator product expansion, we discuss the Dyson-Schwinger approach to this process. Formulated by the parametrization of quark propagators, SU(3) breaking relevant to charm mixing is evaluated in such a way that properly takes account of dynamical chiral symmetry breaking. The ¯ 𝐷 0 →𝐷0 transition is discussed in the vacuum-insertion approximation with locality of the light valence-quark field, represented by the decay constant of 𝐷0 meson as well as relevant momentum integrals. It is found that dimensionless mass-difference observable in this approach leads to |𝑥| =(1.3 – 2.9) ×10−3, the order of magnitude comparable to the HFLAV data, and thereby offering a certain improvement as a theoretical framework.