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arXiv · 2204.09897

Two-particle coalescence conditions revisited

Jacek Karwowski·Andreas Savin
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Abstract

The notion of the n-th order local energy, generated by the n-th power of the Hamiltonian, has been introduced. The n-th order two-particle coalescence conditions have been derived from the requirements that the n-th order local energy at the coalescence point is non-singular and equal to the n-th power of the Hamiltonian eigenvalue. The first condition leads to energy-independent constraints. The second one is state-specific. The analysis has been done using a radial, one-dimensional, model Hamiltonian. The model is valid in the asymptotic region of r ~ 0. The coalescence conditions set the relations between the expansion coefficients of the radial wave function into a power series with respect to r.

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Jacek Karwowski, Andreas Savin. 2022-04-21. Two-particle coalescence conditions revisited. https://doi.org/10.1080/00268976.2022.2069055

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