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Effective operators within the ab initio no-core shell model

Ionel Stetcu·Bruce R. Barrett·Petr Navratil·James P. Vary
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Abstract

We implement an effective operator formalism for general one- and two-body operators, obtaining results consistent with the no-core shell model (NCSM) wave functions. The Argonne V8' nucleon-nucleon potential was used in order to obtain realistic wave functions for 4He, 6Li and 12C. In the NCSM formalism, we compute electromagnetic properties using the two-body cluster approximation for the effective operators and obtain results which are sensitive to the range of the bare operator. To illuminate the dependence on the range, we employ a Gaussian two-body operator of variable range, finding weak renormalization of long range operators (e.g., quadrupole) in a fixed model space. This is understood in terms of the two-body cluster approximation which accounts mainly for short-range correlations. Consequently, short range operators, such as the relative kinetic energy, will be well renormalized in the two-body cluster approximation.

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Ionel Stetcu, Bruce R. Barrett, Petr Navratil, James P. Vary. 2005-03-19. Effective operators within the ab initio no-core shell model. https://doi.org/10.1103/physrevc.71.044325

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