Effective operators within the ab initio no-core shell model
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.
Keywords
Cite
@article{arxiv.nucl-th/0412004,
title = {Effective operators within the ab initio no-core shell model},
author = {Ionel Stetcu and Bruce R. Barrett and Petr Navratil and James P. Vary},
journal= {arXiv preprint arXiv:nucl-th/0412004},
year = {2007}
}
Comments
9 pages, figure added, clarified discussion, to be published in Phys. Rev. C