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Multipair contributions to the spin response of nuclear matter

E. Olsson·C. J. Pethick
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Abstract

We analyse the effect of non-central forces on the magnetic susceptibility of degenerate Fermi systems. These include the presence of contributions from transitions to states containing more than one quasiparticle-quasihole pair, which cannot be calculated within the framework of Landau Fermi-liquid theory, and renormalization of the quasiparticle magnetic moment, as well as explicit non-central contributions to the quasiparticle interaction. Consequently, the relationship between the Landau parameters and the magnetic susceptibility for Fermi systems with non-central forces is considerably more complicated than for systems with central forces. We use sum-rule arguments to place a lower bound on the contribution to the static susceptibility coming from transitions to multipair states.

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E. Olsson, C. J. Pethick. 2002-08-26. Multipair contributions to the spin response of nuclear matter. https://doi.org/10.1103/physrevc.66.065803

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