A Dirac equation with an oscillator potential and spin-orbit coupling

A Schroedinger equation with an oscillator potential and spin-orbit coupling was a fundamental tool in the development of the nuclear shell model. It is thus of interest to propose a Dirac equation with interaction that reduces to the former in the non-relativistic limit. Combining two suggestions recently published in the literature we are able to achieve this objective with the necessary number of parameters. (orig.)