Equation of state for nuclear matter in core-collapse supernovae by the variational method

3rd International Workshop on "State of the Art in Nuclear Cluster Physics"

Togashi, H.^1,2 ; Takehara, Y.^3 ; Yamamuro, S.^3 ; Nakazato, K.^3 ; Suzuki, H.^3 ; Sumiyoshi, K.^4 ; Takano, M.^2,5

Institute for Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama

351-0198, Japan^1

Research Institute for Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo

169-8555, Japan^2

Department of Physics, Faculty of Science and Technology, Tokyo University of Science, Yamazaki 2641, Noda, Chiba

278-8510, Japan^3

Numazu College of Technology, Ooka 3600, Numazu, Shizuoka

410-8501, Japan^4

Department of Pure and Applied Physics, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo

169-8555, Japan^5

关键词: Cluster-variational methods;    Core collapse supernovae;    Density distribution functions;    Density distributions;    Free energy density;    Nuclear equation of state;    Thomas-Fermi approximation;    Three-body potential;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/569/1/012058/pdf
DOI  :  10.1088/1742-6596/569/1/012058

来源: IOP

【 摘 要 】

We construct a new nuclear equation of state (EOS) for core-collapse supernova (SN) simulations using the variational many-body theory. For uniform nuclear matter, the EOS is constructed with the cluster variational method starting from the realistic nuclear Hamiltonian composed of the Argonne v18 two-body potential and the Urbana IX three-body potential. The masses and radii of neutron stars calculated with the obtained EOS at zero temperature are consistent with recent observational data. For non-uniform nuclear matter, we construct the EOS in the Thomas-Fermi approximation. In this approximation, we assume a functional form of the density distributions of protons, neutrons, and alpha-particles, and minimize the free energy density in a Wigner-Seitz cell with respect to the parameters included in the assumed density distribution functions. The phase diagram of hot nuclear matter at a typical temperature is reasonable as compared with that of the Shen EOS.