Bound state properties from the functional renormalization group

Abstract

We discuss an approach for accessing bound state properties, like mass and decay width, of a theory within the functional renormalization group approach. An important cornerstone is the dynamical hadronization technique for resonant interaction channels. The general framework is exemplified and put to work within the two-flavor quark-meson model. This model provides a low-energy description of the dynamics of two-flavor QCD with quark and hadronic degrees of freedom. We compare explicitly the respective results for correlation functions and observables with first principle QCD results in a quantitative manner. This allows us to estimate the validity range of low energy effective models. We also present first results for pole masses and decay widths. Next steps involving real-time formulations of the functional renormalization group are discussed.