Beyond--mean--field effective masses in the nuclear Fermi liquid from axial breathing modes

Abstract

Axial breathing modes are studied within the nuclear energy--density--functional theory to discuss the modification of the nucleon effective mass produced beyond the mean--field approximation. This analysis is peformed with the subtracted second random--phase--approximation (SSRPA) model applied to two nuclei, ${}^{48}$Ca and ${}^{90}$Zr. Analyzing the centroid energies of axial breathing modes obtained with the mean--field--based random--phase approximation and with the beyond--mean--field SSRPA model, we estimate the modification (enhancement) of the effective mass which is induced beyond the mean field. This is done by employing a relation, obtained with the Landau's Fermi liquid theory, between the excitation frequency of axial modes to $\sqrt{m/m^{\ast }}$, where $m$ ($m^{\ast }$) is the bare (effective) mass. Such an enhancement of the effective mass is discussed in connection with the renormalization of single--particle excitation energies generated by the energy--dependent SSRPA self-energy correction. We find that the effective beyond--mean--field compression of the single--particle spectrum produced by the self--energy correction is coherent with the increase of the effective mass estimated from the analysis of axial breathing modes.

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References in corpus (5)

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• Repulsive Fermi polarons in a resonant mixture of ultracold ${}^6$Li atoms
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Cited by in corpus (8)

• Gamow-Teller strength in ${}^{48}$Ca and ${}^{78}$Ni with the charge-exchange subtracted second random-phase approximation
• Non-perturbative Extraction of the Effective Mass in Neutron Matter
• Satisfying the compressibility sum rule in neutron matter
• Neutron matter at the interface(s): static response and effective mass
• Skyrme-based extrapolation for the static response of neutron matter
• The collective excitation of nuclear matter in a bosonized Landau Fermi liquid model
• Shell Model Symmetries-Honoring Franco Iachello
• Recent applications of the subtracted second RPA method