We obtain analytical solutions of the two-body spinless Salpeter (SS) equation with Yukawa potential within the conventional approximation scheme to the centrifugal term for any -state. The semi-relativistic bound state energy spectra and the corresponding normalized wave functions are calculated by means of the Nikiforov-Uvarov (NU) method. We also obtain the numerical energy spectrum of the SS equation without any approximation to centrifugal term for the same potential and compare them with the approximated numerical ones obtained from the analytical expressions. It is found that the exact numerical results are in good agreement with the approximated ones for the lower energy states. Special cases are treated like the nonrelativistic limit and the solution for the Coulomb problem.
The Klein–Gordon equation for a recently proposed Yukawa-type potential is solved with any or-bital quantum number l. In the equally mixed scalar-vector potential fields the approximateenergy eigenvalues and their wave functions for a particle and anti-particle are obtained by means of the parametric Nikiforov–Uvarov method. The non-relativistic solutions are also investigated. It is found that the present analytical results are in exact agreement with the previous ones.