The properties of the neutron star PSR J0348+0432

Abstract

The properties of the massive neutron star PSR J0348+0432 is calculated in the framework of the relativistic mean field theory by choosing the suitable hyperon coupling constants. It is found that the central energy density ${ϵ}_c$ and the central pressure $p_c$ of the massive neutron star PSR J0348+0432 respectively are 1.5 times larger and 3.6 times larger than those of the canonical mass neutron star. It is also found that in the neutron star PSR J0348+0432 there are five kinds of baryons appearing: n, p, $\Lambda$, ${\Xi }^{-}$ and ${\Xi }^0$ but in the canonical mass neutron star there are only three kinds of particles appearing: n, p and $\Lambda$. In our models, the positive well depth $U_{\Sigma }^{(N)}$ will restrict the production of the hyperons ${\Sigma }^{-}$, ${\Sigma }^0$ and ${\Sigma }^{+}$ and therefore either in the neutron star PSR J0348+0432 or in the canonical mass neutron star the hyperons ${\Sigma }^{-}$, ${\Sigma }^0$ and ${\Sigma }^{+}$ all do not appear. In addition, our results also show that the radius $R$ of the massive neutron star PSR J0348+0432 is less than that of the canonical mass neutron star while the gravitational redshift of the former is larger than that of the latter.

Comments: 11 pages, 7 figures, This paper was published in International Journal of Modern Physics D, 2015, 24(8): 1550058