Magnetic moment of nuclei for a momentum-dependent internucleon force

There is a correction to the magnetic-moment operator of nuclei if explicit momentum-dependence is contained in the two-nucleon potential. A simple calculation for this correction in ²⁰⁹Bi shows that it is of the order of +0.55 n.m. This is enough to remove most of the discrepancy from the experimental value that remains after making the corrections for the polarization of the core and the spin-orbit force.