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arXiv · 2401.10533

Barrier penetration in a discrete-basis formalism

G. F. Bertsch·K. Hagino
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Abstract

The dynamics of a many-particle system are often modeled by mapping the Hamiltonian onto a Schr\"odinger equation. An alternative approach is to solve the Hamiltonian equations directly in a model space of many-body configurations. In a previous paper the numerical convergence of the two approaches was compared with a simplified treatment of the Hamiltonian representation. Here we extend the comparison to the nonorthogonal model spaces that would be obtained by the generator-coordinate method. With a suitable choice of the collective-variable grid, a configuration-interaction Hamiltonian can reproduce the Schr\"odinger dynamics very well. However, the method as implemented here requires that the barrier height is not much larger than the zero-point energy in the collective coordinates of the configurations.

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BibTeXRIS

G. F. Bertsch, K. Hagino. 2024-01-19. Barrier penetration in a discrete-basis formalism. https://arxiv.org/abs/2401.10533

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