Seminars

Energy-density-functional results for magic nuclei and the extrapolations to the nuclear matter equations of state for neutron stars

I will discuss results from the references below for the applications of Skyrme energy-density functionals to properties of doubly-magic nuclei, ab-initio calculations of low-density neutron matter, and neutron stars. The correlation between the neutron skin and the slope of the neutron equation of state near a density of 0.10 nucleons/fm^3 discovered in ( 1,2,3) was extended to the differences in the charge radii of mirror nuclei (4). Alternatively, when the Skyrme parameters are constrained by ab-initio calculations of low-density neutron matter, predictions can be made for the neutron skin and the slope of the neutron equation of state (4). The maximum mass of the neutron star depends on the neutron effective mass. A value of [m ∗ n /m](ρ 0 ) = 0.60-0.65 is required to obtain a maximum neutron star mass of 2.1 solar masses (6). With the constraints to the low-density neutron matter and neutron star mass, a value of 12.4(1) km is predicted for the radius of a 1.4 solar mass neutron star.
1) Neutron Radii in Nuclei and the Neutron Equation of State, Phys. Rev. Lett. 85, 5296 (2000).
2) Neutron Radii and the Neutron Equation of State in Relativistic Models, Phys. Rev. C64, 027302 (2001).
3) Constraints on the Skyrme Equations of State from Properties of Doubly Magic Nuclei, Phys. Rev. Lett. 111, 232502 (2013).
4) Constraints on the Skyrme Equations of State from Properties of Doubly Magic Nuclei and ab initio Calculations of Low-Density Neutron Matter, Phys. Rev. C 89, 011307(R) (2014).
5) Mirror Charge Radii and the Neutron Equation of State, Phys. Rev. Lett. 119, 122502 (2017).
6) C. Y. Tsang, B. A. Brown, F.J. Fattoyev, W. G. Lynch, and M. B. Tsang, arXiv:1908.11842v1.