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arXiv · 0708.3754

Convergence in the no-core shell model with low-momentum two-nucleon interactions

S. K. Bogner·R. J. Furnstahl·P. Maris·R. J. Perry·A. Schwenk·J. P. Vary
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Abstract

The convergence of no-core shell model (NCSM) calculations using renormalization group evolved low-momentum two-nucleon interactions is studied for light nuclei up to Li-7. Because no additional transformation was used in applying the NCSM framework, the energy calculations satisfy the variational principle for a given Hamiltonian. Dramatic improvements in convergence are found as the cutoffs are lowered. The renormalization group equations are truncated at two-body interactions, so the evolution is only approximately unitary and converged energies for A > 2 vary with the cutoff. This approximation is systematic, however, and for useful cutoff ranges the energy variation is comparable to natural-size truncation errors inherent from the initial chiral effective field theory potential.

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S. K. Bogner, R. J. Furnstahl, P. Maris, R. J. Perry, A. Schwenk, J. P. Vary. 2007-11-30. Convergence in the no-core shell model with low-momentum two-nucleon interactions. https://doi.org/10.1016/j.nuclphysa.2007.12.008

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