RT Journal Article T1 Temperature dependence of the symmetry energy and neutron skins in Ni, Sn, and Pb isotopic chains A1 Antonov, A. N. A1 Kadrev, D. N. A1 Gaidarov, M. K. A1 Sarriguren, P. A1 Moya de Guerra, Elvira AB The temperature dependence of the symmetry energy for isotopic chains of even-even Ni, Sn, and Pb nuclei is investigated in the framework of the local density approximation (LDA). The Skyrme energy density functional with two Skyrme-class effective interactions, SkM* and SLy4, is used in the calculations. The temperature-dependent proton and neutron densities are calculated through the HFBTHO code that solves the nuclear Skyrme-Hartree-Fock-Bogoliubov problem by using the cylindrical transformed deformed harmonic-oscillator basis. In addition, two other density distributions of Pb-208, namely the Fermi-type density determined within the extended Thomas-Fermi (TF) method and symmetrized-Fermi local density obtained within the rigorous density functional approach, are used. The kinetic energy densities are calculated either by the HFBTHO code or, for a comparison, by the extended TF method up to second order in temperature (with T-2 term). Alternative ways to calculate the symmetry energy coefficient within the LDA are proposed. The results for the thermal evolution of the symmetry energy coefficient in the interval T = 0-4 MeV show that its values decrease with temperature. The temperature dependence of the neutron and proton root-mean-square radii and corresponding neutron skin thickness is also investigated, showing that the effect of temperature leads mainly to a substantial increase of the neutron radii and skins, especially in the more neutron-rich nuclei, a feature that may have consequences on astrophysical processes and neutron stars. PB American Physical Society SN 2469-9985 YR 2017 FD 2017-02-14 LK https://hdl.handle.net/20.500.14352/17804 UL https://hdl.handle.net/20.500.14352/17804 LA eng NO © American Physical Society 2017E. Moya de Guerra and O. Moreno acknowledge MINECO for partial financial support (FIS2014-51971-P) and IEM-CSIC for hospitality. O. Moreno acknowledges support from a Marie Curie International Outgoing Fellowship within the European Union Seventh Framework Programme, under Grant Agreement PIOF-GA-2011-298364 (ELECTROWEAK). M. R. M. thanks N. G. Sanchez for correspondence and conversations. NO Ministerio de Economía y Competitividad (MINECO) NO Bulgarian Science Fund DS Docta Complutense RD 22 mar 2026