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Microscopic origins of effective charges in the shell model

P. Navratil·M. Thoresen·B. R. Barrett
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Abstract

We use a large-scale 6 hbar Omega calculation for Li6 with microscopically derived two-body interaction to construct the 0 hbar Omega 0p-shell effective hamiltonian, electric quadrupole, and magnetic dipole operators. While the E2 and M1 6 hbar Omega operators are one-body operators with free nucleon charges, the effective operators are two-body operators with substantially different renormalization for the isoscalar and isovector matrix elements, especially for the E2 operator. We show that these operators can be very well approximated by one-body operators provided that effective proton and neutron charges are used. The obtained effective charges are compatible with those used in phenomenological shell-model studies. The two-body part of the effective operators is estimated.

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P. Navratil, M. Thoresen, B. R. Barrett. 1996-12-05. Microscopic origins of effective charges in the shell model. https://doi.org/10.1103/physrevc.55.573

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