Differential-equation reduction of principal-value collision integrals in nonrelativistic perturbation theory
Tóm tắt
An iterative differential-equation approach to the evaluation of principal-value integrals occurring in perturbation calculations is examined within the framework ofT-matrix collision theory. Such procedure also leads to an interesting representation of nonrelativistic perturbation theory, and can simplify calculation of scattering matrix elements for smooth potentials.
Tài liệu tham khảo
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The factor 2/π properly normalizes the projection over statesk.
Formally, the caseh=q requires the evaluation of the residue of a double pole in eqs. (32) and (33).