Relativistic model of nucleon and pion structure: Static properties and electromagnetic soft form factors

I have studied the valence-quark system in a light-cone version of the constituent-quark model. A relativistic description is derived by applying light-cone boosts to model wave functions at rest which describe a valence system with the standard quark-model $J^P$ assignments, the usual constituent-quark mass, and a universal hadronic scale. With the scale fixed by static properties at ≊320 MeV, we find that the relativistic constituent-quark model offers an excellent description of the hadron electromagnetic form factors up to $Q^2$≊few ${\mathrm{GeV}}^2$, but at larger scales is invalid.