A perfect fluid model for compact stars

摘要

In the framework of Einstein's theory of general relativity we present a new interior solution with a perfect fluid; this is constructed from the proposal of a gravitational redshift factor. The geometry is regular and density and pressure are monotonic decreasing functions; furthermore, the sound speed is smaller than the light speed and monotonic increasing. The solution depends on a parameter w is an element of (0, 2.037 550 932 5] related to the compactness of the star u = GM/c(2)R, the maximum value of which is u = 0.266 085 831 6, which allows for describing compact stars like quark stars or neutron stars. Although there is a diversity of stars for which the model can be used, we only apply this solution to describe the interior of a neutron star PSR J0348+0432. According to the observations, it is known that its mass M = (2.01 +/- 0.04) M-circle dot and its radius is between 12 062 and 12 957 km, so the value of the compactness is in the range u is an element of [0.224 484 5, 0.250 933 8]. In addition to the decreasing behavior of the mentioned pressure and density functions, the results are consistent with the density value range typical of neutron stars and the maximal central density of the star result to be 1.283 818 x 10(18) kg/m(3).