Equivalence between the space fixed and the body fixed formulations of the j/sub z/-conserving approximation

It is shown that space fixed and the body fixed formulations of the j/sub z/-conserving approximation are equivalent if the partial wave parameter l-bar is chosen equal to the final orbital angular momentum l'. We also examine the replacement of l-bar by l, the initial orbital angular momentum in the space fixed formulation. Only these two choices of l-bar give simple expressions for the scattering amplitude