Analytical model of strange star in the low-mass X-ray binary 4U 1820-30

In this article, we have proposed a model for a realistic strange star under Tolman VII metric\citep{Tolman1939}. Here the field equations are reduced to a system of three algebraic equations for anisotropic pressure. Mass, central density and surface density of strange star in the low-mass X-ray binary 4U 1820-30 has been matched with the observational data according to our model. Strange materials clearly satisfies the stability condition (i.e. sound velocities < 1) and TOV-equation. Here also surface red shift of the star has been found to be within reasonable limit.Comment: Some revisions have been made. Accepted in Eur.Phys.J.

Possible Existence of Dark Matter Admixed Pulsar in M31 and M87 Galaxies

In previous studies [1, 2, 3] the possible existence dark matter admixed pulsar have been discussed based on three different dark matter density profiles, Singular Isothermal Sphere density profile, Universal Rotational Curve density profile and Navarro-Frenk-White density profile. They have been used to discuss the pulsars present in our Milky Way galaxy as well as some satellite dwarf galaxies of Milky Way. In this article we use the Universal Rotational Curve (URC) dark matter density profile to observe similar effects on galaxies M31 and M87. These study hold significant importance, as now it can be concluded that there is a fair possibility of presence of dark matter admixed pulser in M31 and M87 galaxies as well.Comment: 17 pages, 16 figures, 2 table

PossibleExistence of Dark-Matter-Admixed Pulsar in the Disk Region of the Milky Way Galaxy

In our previous study, (Eur Phys J Plus 135:362, 2020 &amp; Eur Phys J Plus 135:637, 2020), we have discussed the possible existence of the dark-matter-admixed pulsars, located in dwarf as well as in massive spiral galaxies (based on Singular Isothermal Sphere dark-matter density profile) and in the Milky Way galaxy (based on Universal Rotational Curve dark-matter density profile). In this article, we use the Navarro&ndash;Frenk&ndash;White (NFW) dark-matter density profile to get analogous results for the pulsars in the disk region of the Milky Way galaxy. These findings may be treated as valuable complements to the previous findings. We conclude from our findings that there is a unique possibility of the presence of dark-matter-admixed pulsars in all the regions of the galaxies