Probing the Infrared Quark Mass from Highly Excited Baryons

We argue that three-quark excited states naturally group into quartets, split into two parity doublets, and that the mass splittings between these parity partners decrease higher up in the baryon spectrum. This decreasing mass difference can be used to probe the running quark mass in the midinfrared power-law regime. A measurement of masses of high-partial-wave Δ* resonances should be sufficient to unambiguously establish the approximate degeneracy. We test this concept with the first computation of excited high-j baryon masses in a chirally invariant quark model.