QCD phenomenology with infrared finite SDE solutions

Understand

Recent progress in the solution of Schwinger-Dyson equations (SDE), as well as lattice simulation of pure glue QCD, indicate that the gluon propagator and coupling constant are infrared (IR) finite.

• We discuss how this non-perturbative information can be introduced into the QCD perturbative expansion in a consistent scheme, showing some examples of tree level hadronic reactions that successfully fit the experimental data with the gluon propagator and coupling constant depending on a dynamically generated gluon mass.
• This infrared mass scale acts as a natural cutoff and eliminates some of the ad hoc parameters usually found in perturbative QCD calculations.
• The application of these IR finite Green's functions in the case of higher order terms of the perturbative expansion is commented.