Observation of Padé summability in divergentL2complex coordinate calculations oft-matrix amplitudes in the presence of long-range forces

The method of complex coordinates has long been known to allow $L^2$ calculations of $t$-matrix amplitudes for short-range potentials, but to yield divergent results for long-range forces. Using a spherical long-range potential as an example, it is shown here that the Padé method of summation can be used in conjunction with the diverging complex-coordinate calculations to obtain accurate values of the scattering amplitude.