The Levy-Leblond equation in a central field

The eigenfunctions of the Dirac operator in a central field can be written in the form (7) 

The solutions of the LLE in a central field have an analogous form, and satisfy the radial LLE 

We solve the second line of (43) for /o(r) and insert this into the first line of (43) 

Let us consider the Is ground state and the lowest 2p-state of H-like ions For the Is-state (n = 1, /c = — 1) we have 

---