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Comparative variational studies of $0^+$ states in three-$α$ models

E. M. Tursunov·D. Baye·P. Descouvemont
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Abstract

Three variational approaches, the hyperspherical-harmonics, Gaussian-basis and Lagrange-mesh methods involving different coordinate systems, are compared in studies of $0^+$ bound-state energies in 3$α$ models. Calculations are performed with different versions of the shallow Ali-Bodmer potential (with and without Coulomb) and with the deep Buck-Friedrich-Wheatley potential. All three methods yield very accurate energies. Their advantages and drawbacks are evaluated. The implications of the disagreement between the obtained results and the experimental $^{12}$C energies in $3α$ models with Coulomb interaction are discussed.

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E. M. Tursunov, D. Baye, P. Descouvemont. 2005-01-25. Comparative variational studies of $0^+$ states in three-$α$ models. https://doi.org/10.1016/s0375-9474(03)01323-x

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