Speaker
Description
Traditional lore of meson decays suggested that the production of a quark-antiquark pair from the chromoelectric field would happen in a 3P0 state (a scalar state with aligned spins and a relative L=1 wave). This are not the quantum numbers of the tree-level interaction in QCD. Moreover, they are not produced at any order in perturbation theory because the theory is to a good approximation chirally symmetric. Thus, such production vertex has to arise simultaneously to the constituent quark mass.
The last decade has brought detailed lattice data for the primitive vertices of QCD in Landau gauge. A practical use of this data has been to constrain Dyson-Schwinger parametrizations of the most elementary QCD Green's functions, that are now reasonably well known.
With this knowledge of the underlying theory in the infrared regime we attempt to connect the Landau gauge formalism and the constituent quark model to ascertain the relative size of the various possible structures in the quark-antiquark production vertex, including the postulated 3P0 quark-model piece.
