Ab initiocalculation of relativistic corrections to the static interquark potential: SU(2) gauge theory

We test the capability of state-of-the-art lattice techniques for a precise determination of relativistic corrections to the static interquark potential by use of SU(2) gauge theory. Emphasis is put on the short-range structure of the spin-dependent potentials, with the lattice resolution $a$ ranging from $a\approx 0.04\mathrm{fm}$ (at $\beta =2.74\mathrm{}$) down to $a\approx 0.02\mathrm{fm}$ (at $\beta =2.96\mathrm{}$) on volumes of ${32}^4$ and ${48}^4$ lattice sites. We find a new Coulomb-like contribution to the long-range spin-orbit potential $V_1^{\prime }.$