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arXiv · 0704.2854

Coupled-cluster theory for three-body Hamiltonians

G. Hagen·T. Papenbrock·D. J. Dean·A. Schwenk·A. Nogga·M. Wloch·P. Piecuch
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Abstract

We derive coupled-cluster equations for three-body Hamiltonians. The equations for the one- and two-body cluster amplitudes are presented in a factorized form that leads to an efficient numerical implementation. We employ low-momentum two- and three-nucleon interactions and calculate the binding energy of He-4. The results show that the main contribution of the three-nucleon interaction stems from its density-dependent zero-, one-, and two-body terms that result from the normal ordering of the Hamiltonian in coupled-cluster theory. The residual three-body terms that remain after normal ordering can be neglected.

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G. Hagen, T. Papenbrock, D. J. Dean, A. Schwenk, A. Nogga, M. Wloch, P. Piecuch. 2007-09-07. Coupled-cluster theory for three-body Hamiltonians. https://doi.org/10.1103/physrevc.76.034302

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