Semirelativistic quark model of pion-pion scattering

Pion-pion scattering is investigated in terms of underlying quark dynamics. The wave function of an isolated pion, described as a quark-antiquark syst em interacting through a potential composed of a central and a spin-spin pa rt, is determined by using the spinless Salpeter equation. The kernel of th e integro-differential equation governing the relative motion of the collid ing pions is calculated by using relativistic kinematics. The corresponding S- and D-wave pion-pion phase shifts and their Galilean counterparts are c ompared with experimental data.