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arXiv · 0906.4276

Center-of-mass problem in truncated configuration interaction and coupled-cluster calculations

Robert Roth·Jeffrey R. Gour·Piotr Piecuch
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Abstract

The problem of center-of-mass (CM) contaminations in ab initio nuclear structure calculations using configuration interaction (CI) and coupled-cluster (CC) approaches is analyzed. A rigorous and quantitative scheme for diagnosing the CM contamination of intrinsic observables is proposed and applied to ground-state calculations for He-4 and O-16. The CI and CC calculations for O-16 based on model spaces defined via a truncation of the single-particle basis lead to sizable CM contaminations, while the importance-truncated no-core shell model based on the $N_{\max}\hbarΩ$ space is virtually free of CM contaminations.

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Robert Roth, Jeffrey R. Gour, Piotr Piecuch. 2009-08-05. Center-of-mass problem in truncated configuration interaction and coupled-cluster calculations. https://doi.org/10.1016/j.physletb.2009.07.071

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