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Smooth spectral transition from Coulomb to oscillator

Richard L. Hall
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Abstract

Non-relativistic potential models are considered of the pure power V(r) = sgn(q) r^q and logarithmic V(r) = ln(r) types. Envelope representations and kinetic potentials are employed to show that these potentials are actually in a single family. The log spectra can be obtained from the power spectra by the limit q --> 0 taken in a smooth representation P_{n\ell}(q) for the eigenvalues E_{n\ell}(q). A simple approximation formula is developed which yields the first thirty eigenvalues with error < 0.04%. Extensions to potentials with linear combinations of terms such as -a/r + br and applications to spatially-symmetric few-body problems are discussed.

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Richard L. Hall. 2000-06-27. Smooth spectral transition from Coulomb to oscillator. https://arxiv.org/abs/math-ph/0006025

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