Analytical model of strange star in low-mass X-ray binary KS 1731-260

Abstract

In this article using Mehra (Aust. Math. Soc. 6:153, 1966) metric, we propose a model for the strange star in low-mass X-ray binary (LMXB) KS 1731-260 (Özel et al., Astrophys. J. 748:5, 2012) which describes interior space-time of the star. We study the strange star’s interior and exterior physical properties. We calculate central density ($\rho_{0}$), surface density ($\rho_{b}$), central pressure ($p _{0}$), surface redshift ($Z _{s}$) and probable radius of the above mentioned strange star, which is very much consistent with the reported data. The special feature of this article is that the radius of the star is 12.31 km where pressure becomes zero and mass comes out as $2.09521 M_{\odot }$, whereas maximum mass comes out as $2.09996 M _{\odot }$ with radius 12.53 km. Therefore, our model suggests that there may be a gaseous atmosphere over a range of 0.22 km outside of the stellar structure which justify the claim of Ho and Heinke (Nature 462:71, 2009).