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Effective range function below threshold

A. Deloff
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Abstract

We demonstrate that the kernel of the Lippmann-Schwinger equation, associated with interactions consisting of a sum of the Coulomb plus a short range nuclear potential, below threshold becomes degenerate. Taking advantage of this fact, we present a simple method of calculating the effective range function for negative energies. This may be useful in practice since the effective range expansion extrapolated to threshold allows to extract low-energy scattering parameters: the Coulomb-modified scattering length and the effective range.

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A. Deloff. 2000-06-26. Effective range function below threshold. https://doi.org/10.1088/0954-3899%2F26%2F12%2F306

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