Treatment of the Coulomb singularity in momentum space calculations Original Research Article

The evaluation of the matrix elements of the Coulomb interaction in calculations using the Lippmann–Schwinger (or related) equations is complicated by the existence of a singularity in the integrand. One method of handling this singularity is to use a procedure commonly called the Lande subtraction. A procedure is outlined which relates the subtraction integrals to formulae involving the zeros of Legendre polynomials. This is used to compute tables of subtraction integrals that can be used to improve the precision of integrations performed with the Lande subtraction.