2015/02/17 by Bizarro, Daniel, Rabhi, Aziz, Providência, Constança
#FOS: Physical sciences #Nuclear Theory (nucl-th)
paper · doi:10.48550/arxiv.1502.04952
The joint effect of the density dependence of the symmetry energy and strangeness content on the structure of cold neutron stars is studied within the framework of a relativistic mean field theory. It is shown that 2M_\odot are obtained for repulsive YY interaction and preferably for a small or a large slope L. An attractive Σ potential in nuclear matter will favor the appearance of strangeness in stars with a mass as small as ∼ 1 M_\odot, if, however it is repulsive only stars with a mass \gtrsim 1.4 M_\odot will contain strangeness. The joint effect of reducing the symmetry energy slope and including hyperons is to farther reduce the radius. Neutron star maximum mass evolve non-monotonically with the symmetry energy slope, and the smallest masses are obtained for values L∼ 80 MeV. Other neutron star variables evolve nonlinearly with the slope of the symmetry energy and depend on the hyperon-nucleon and hyperon-hyperon couplings. The radius of a neutron star is linearly correlated with the neutron star total strangeness fraction and the slope is independent of the slope of the symmetry energy and the mass of the star.