Center-of-mass problem in truncated configuration interaction and coupled-cluster calculations
arXiv:0906.4276 · doi:10.1016/j.physletb.2009.07.071
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.
6 pages, 1 figure, 2 tables; v2: minor modifications, Phys. Lett. B in print