Static spin-dependent forces between heavy quarks in the classical approximation to dual QCD

Abstract

We compute the static spin-dependent forces VS(R) (proportional to σ_1•σ_2) and V_T(R) (proportional to 3σ_1•Ȓσ_2•Ȓ-σ_1•σ_2) between two quarks separated by R. This is done by treating the (weak) spin-dependent effects as a perturbation on the spin-independent potentials and fields computed earlier for dual QCD. What results is a definite prediction for the heavy-quark potentials which are similar to, but different in form from, those used in phenomenological treatments. Calculations of the masses and splittings of heavy-quark states using our potentials will provide a further test of the dual superconductor picture of QCD.