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A renormalisation-group approach to two-body scattering with long-range forces

Thomas Barford·Michael C. Birse
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Abstract

We apply the renormalisation-group to two-body scattering by a combination of known long-range and unknown short-range forces. A crucial feature is that the low-energy effective theory is regulated by applying a cut-off in the basis of distorted waves for the long range potential. We illustrate the method by applying it to scattering in the presence of a repulsive 1/r^2 potential. We find a trivial fixed point, describing systems with weak short-range interactions, and a unstable fixed point. The expansion around the latter corresponds to a distorted-wave effective-range expansion.

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Thomas Barford, Michael C. Birse. 2001-08-10. A renormalisation-group approach to two-body scattering with long-range forces. https://doi.org/10.1063/1.1436603

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