Dynamical suppression of the spin-orbit interaction in hadrons

Abstract

Spin-dependent interaction in hadrons is considered in the approach of the QCD string. The string moment of inertia, which ensures the correct (inverse) Regge slope 2*pi*sigma, is found to suppress the spin-orbit interaction. For light quarks and moderate angular momenta the suppression constitutes around 25% whereas for large angular momenta the spin-orbit interaction is suppressed by the factor L^(-2/5). For heavy quarks the effect manifests itself as a string correction for the spin-dependent potential.