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Generator Coordinate Truncations

K. Hagino·G. F. Bertsch·P. -G. Reinhard
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Abstract

We investigate the accuracy of several schemes to calculate ground-state correlation energies using the generator coordinate technique. Our test-bed for the study is the $sd$ interacting boson model, equivalent to a 6-level Lipkin-type model. We find that the simplified projection of a triaxial generator coordinate state using the $S_3$ subgroup of the rotation group is not very accurate in the parameter space of the Hamiltonian of interest. On the other hand, a full rotational projection of an axial generator coordinate state gives remarkable accuracy. We also discuss the validity of the simplified treatment using the extended Gaussian overlap approximation (top-GOA), and show that it works reasonably well when the number of boson is four or larger.

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K. Hagino, G. F. Bertsch, P. -G. Reinhard. 2003-04-17. Generator Coordinate Truncations. https://doi.org/10.1103/physrevc.68.024306

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