Interaction model for the gap equation

We explain a form for the rainbow-ladder kernel whose momentum dependence is consonant with modern DSE- and lattice-QCD results, and assess its capability as a tool in hadron physics. In every respect tested, this form produces results for observables that are at least equal to the best otherwise obtained in a comparable approach. Moreover, it enables the natural extraction of a monotonic running-coupling and gluon mass.

Figure 1

Upper panel: Rainbow-ladder gluon running-mass inferred from Eq. (8) via Eq. (10). Lower panel: Rainbow-ladder effective running coupling inferred from Eq. (8). In both panels $\omega =0.5$ GeV (solid curve) and $\omega =0.6$ GeV (dashed curve).