S. Panchanan et al., MODIFIED SHIFTED 1 N EXPANSION FOR RELATIVISTIC YUKAWA AND HULTHEN POTENTIALS/, Canadian journal of physics, 74(3-4), 1996, pp. 136-140
The shifted 1/N expansion technique is applied to the radial Dirac equ
ation. it is shown that the fixing condition E(1) = 0 produces an enha
nced accuracy for Yukawa and Hulthen potentials. The modified shifted
1/N expansion results are compared with the exact numerical results an
d results obtained by other approximate methods.