Work

Multicomponent Fermi systems at low densities

Year: 2025

Type: article

Abstract: We calculate, to second order in the scattering length between two fermions, the Landau quasiparticle interaction for a low-density mixture of two fermion species with unequal densities at temperature zero. From the Landau parameters we evaluate the energy density and find agreement with the result of Kanno []. The calculations are then extended to the case of two fermion components with different total densities, each with two spin components, a situation of interest in nuclear physics and astrophysics, where the species are neutrons and protons. An interesting finding is that, for low proton concentrations, x ≪ 1 , the leading term in the energy density, beyond the x 5 / 3 contribution from the kinetic energy and the x 2 one due to the two-body interaction in the mean-field approximation, varies as x 7 / 3 ln x . This is to be contrasted with the higher powers of x implicit in many phenomenological energy-density functionals employed in nuclear physics, such as those of the Skyrme type.

Source: Physical Review C

DOI: 10.1103/physrevc.111.035808

Authors: C. J. Pethick, A. Schwenk

Institutions: Nordic Institute for Theoretical Physics, University of Copenhagen, GSI Helmholtz Centre for Heavy Ion Research, Technische Universität Darmstadt, Max Planck Institute for Nuclear Physics

Language: English

Topic: Nuclear physics research studies

Subfield: Nuclear and High Energy Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: hybrid

Funders: European Commission, NordForsk, European Research Council, Horizon 2020

Awards: G19405907, G2060252402, G434337789