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arXiv · 2502.09911

Improvement to Generalized Separable Expansion Method in Lippmann-Schwinger Equation

Hiroyuki Kamada
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Abstract

Realistic nucleon-nucleon (NN) potentials are generally not in separable form, but there is a way to convert them into separable potentials, called the generalized separable expansion (GSE). When the separable potential is substituted into a three-body Faddeev equation, which generally has two Jacobi momenta, the integral equation is conveniently reduced to a one-variable integral equation. The two-body scattering t-matrix of the conventional GSE does not have an exact singularity at the energy threshold of the two-body bound state. The newly introduced GSE improves this by treating the singularity analytically.

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Hiroyuki Kamada. 2025-02-14. Improvement to Generalized Separable Expansion Method in Lippmann-Schwinger Equation. https://doi.org/10.1093/ptep%2Fptaf074

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