An anisotropic charged fluids with Chaplygin equation of state
Abstract
A stellar model with an electrically charged anisotropic fluid as a source of matter is presented. The radial pressure is described by a Chaplygin state equation, Pr(ρ)=μc2ρ−ν/(c2ρ), while the anisotropy Δ≡Pt−Pr=r2f(r) is annulled in the center of the star (f(r) is regular and f(0)≠0), the electric field, is also annulled in the center. The density pressures and the tangential speed of sound are regular, while the radial speed of sound is monotonically increasing. The model is physically acceptable and meets the stability criteria of Harrison–Zeldovich–Novikov and in respect of the cracking concept the solution is unstable in the region of the center and potentially stable near the surface. A graphic description is presented for the case of an object with a compactness rate u=0.27336, mass M=1.77M⊙ and radius R=9.56 km that matches the star Vela X-1. Also, the interval of the central density ρc∈[1.176977292,1.308791129]1018kg/m3, which is consistent with the expected magnitudes for this type of stars, which shows that the behavior is accurate for describing compact objects.
