Relativistic fluid spheres with Karmarkar condition

摘要

We present a family of relativistic fluid spheres using the Karmarkar criterion along with the Pandey-Sharma condition. Ranges of n and in for well-behaved solutions depend on the mass and radius of the compact star model. As an example, we have chosen Vela X-1 (M = 1.77M(circle dot), R = 9.56 km) for complete analysis of the solutions. For the same star, the well-behaved ranges are 1 < n < 5 and 3 < m < 13. However, beyond these limits, either the transversal sound speed becomes imaginary or violates the causality principle. Further, the critical part of our solution is that corresponding to every nonzero positive even value of m yields zero values of all the physical quantities.