We study the thermal properties of ${}^{54}\mathrm{Fe}$ with the Brown-Richter interaction in the complete $1p0f$ model space. Monte Carlo calculations show a peak in the heat capacity and rapid increases in both the moment of inertia and $M1$ strength near a temperature of 1.1 MeV that are associated with the vanishing of proton-proton and neutron-neutron monopole pair correlations; neutron-proton correlations persist to higher temperatures. Our results are consistent with a Fermi gas level density whose backshift vanishes with increasing temperature.We study the thermal properties of ${}^{54}\mathrm{Fe}$ with the Brown-Richter interaction in the complete $1p0f$ model space. Monte Carlo calculations show a peak in the heat capacity and rapid increases in both the moment of inertia and $M1$ strength near a temperature of 1.1 MeV that are associated with the vanishing of proton-proton and neutron-neutron monopole pair correlations; neutron-proton correlations persist to higher temperatures. Our results are consistent with a Fermi gas level density whose backshift vanishes with increasing temperature.

arXiv:nucl-th/9405005Physical Review LettersApr 10, 199570 citations

Proton-neutron entanglement in the nuclear shell model

Calvin W. Johnson, Oliver C. Gorton

Abstract We compute the proton-neutron entanglement entropy in the interacting nuclear shell model for a variety of nuclides and interactions. Some results make intuitive sense, for example, that the shell structure, as governed by single-particle and monopole energies, strongly affects the energetically available space and thus the entanglement entropy. We also find a surprising result: that the entanglement entropy at low excitation energy tends to decrease for nuclides when N ≠ Z. While we provide evidence this arises from the physical nuclear force by contrasting with random two-body interactions which shows no such decrease, the exact mechanism is unclear. Nonetheless, the low entanglement suggests that in models of neutron-rich nuclides, the coupling between protons and neutrons may be less computationally demanding than one might otherwise expect.Abstract We compute the proton-neutron entanglement entropy in the interacting nuclear shell model for a variety of nuclides and interactions. Some results make intuitive sense, for example, that the shell structure, as governed by single-particle and monopole energies, strongly affects the energetically available space and thus the entanglement entropy. We also find a surprising result: that the entanglement entropy at low excitation energy tends to decrease for nuclides when N ≠ Z. While we provide evidence this arises from the physical nuclear force by contrasting with random two-body interactions which shows no such decrease, the exact mechanism is unclear. Nonetheless, the low entanglement suggests that in models of neutron-rich nuclides, the coupling between protons and neutrons may be less computationally demanding than one might otherwise expect.

arXiv:2210.14338Journal of Physics G Nuclear and Particle PhysicsFeb 24, 202348 citations

We study the thermal properties of

{}^{54}\mathrm{Fe}

with the Brown-Richter interaction in the complete

1p0f

model space. Monte Carlo calculations show a peak in the heat capacity and rapid increases in both the moment of inertia and

M1

strength near a temperature of 1.1 MeV that are associated with the vanishing of proton-proton and neutron-neutron monopole pair correlations; neutron-proton correlations persist to higher temperatures. Our results are consistent with a Fermi gas level density whose backshift vanishes with increasing temperature.