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arXiv · 2405.18184

Three-body Forces in Oscillator Bases Expansion

Cyrille Chevalier·Selma Youcef Khodja
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Abstract

The oscillator bases expansion stands as an efficient approximation method for the time-independent Schr\"odinger equation. The method, originally formulated with one non-linear variational parameter, can be extended to incorporate two such parameters. It handles both non- and semi-relativistic kinematics with generic two-body interactions. In the current work, focusing on systems of three identical bodies, the method is generalised to include the management of a given class of three-body forces. The computational cost of this generalisation proves to not exceed the one for two-body interactions. The accuracy of the generalisation is assessed by comparing with results from Lagrange mesh method and hyperspherical harmonic expansions. Extensions for systems of $N$ identical bodies and for systems of two identical particles and one distinct are also discussed.

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Cyrille Chevalier, Selma Youcef Khodja. 2024-05-28. Three-body Forces in Oscillator Bases Expansion. https://doi.org/10.1007/s00601-024-01951-z

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