Programme

P.15 -- Poster, VCTP-44

Date: Tuesday, 30 July 2019

Time: 08:30 - 10:00

The study of neutron star: Nuclear matter Equation of state and Symmetry energy

Ngo Hai Tan (1,2), Dao Tien Khoa (3), Phung Van Đong (2)

1 Faculty of Basic Sciences, Phenikaa University, Hanoi 12116, Vietnam 2 Phenikaa Institute for Advanced Study (PIAS), Phenikaa University, Hanoi 3 Institute for Nuclear Science and Technology, VINATOM, 179 Hoang Quoc Viet, Cau Giay, Hanoi

We introduce the study of the equation of state (EOS) of the neutron star (NS) matter. The equation of state (EOS) of asymmetric the nuclear matter has been obtained from the nuclear mean-field potentials in the Hartree-Fock (HF) method. Different in-medium nucleon-nucleon (NN) interaction has been chosen as input for the HF many-body problem: version Sly4 of the Skyrme zero-range interaction; two density-dependent versions of the finite-range M3Y interaction (CDM3Yn and M3Y-Pn), and versions D1S and D1N of the Gogny interaction. Although the considered effective NN interactions were proven to be quite realistic in numerous nuclear structure and/or reaction studies, they give quite different behaviors of the symmetry energy of nuclear matter at supranuclear densities that lead to the soft and stiff scenarios discussed recently in the literature [1, 2]. The EOS of the uniform core inside neutron star has been calculated for the npeµ composition in the β equilibrium at zero and finite temperature, without and with spin-polarization of nucleons. Different EOS’s of the NS core and the EOS of the NS crust given by the compressible liquid drop model have been used as input of the Tolman-Oppenheimer-Volkov equations to determine the hydrostatic configurations. We study how the nuclear symmetry energy affects the model prediction of different NS properties, like the cooling process as well as the gravitational mass and radius. [1] Doan Thi Loan, Ngo Hai Tan, Dao T. Khoa, and Jerome Margueron, “Equation of state of neutron star matter, and the nuclear symmetry energy”, Physical Review C 83, 065809 (2011). [2] Ngo Hai Tan, Doan Thi Loan, Dao T. Khoa, and Jerome Margueron, “Mean-field study of hot β-stable protoneutron star matter: Impact of the symmetry energy and nucleon effective mass”, Physical Review C 93, 035806 (2016).

Presenter: Ngo Hai Tan