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Asymptotic phase shifts and Levinson theorem for 2D potentials with inverse square singularities

Denis D. Sheka·Boris A. Ivanov·Franz G. Mertens
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Abstract

The Levinson theorem for two-dimensional scattering is generalized for potentials with inverse square singularities. By this theorem, the number of bound states in a given m-th partial wave is related to the phase shift and the singularity strength of the potential. For the m-wave phase shift the asymptotic behaviour is calculated for short wavelengths.

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Denis D. Sheka, Boris A. Ivanov, Franz G. Mertens. 2003-10-04. Asymptotic phase shifts and Levinson theorem for 2D potentials with inverse square singularities. https://doi.org/10.1103/physreva.68.012707

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