A well-behaved class of charged analogue of Durgapal solution

Abstract

We present a well behaved class of charged analogue of M.C. Durgapal (J. Phys. A, Math. Gen. 15:2637, 1982) solution. This solution describes charged fluid balls with positively finite central pressure, positively finite central density; their ratio is less than one and causality condition is obeyed at the centre. The outmarch of pressure, density, pressure-density ratio and the adiabatic speed of sound is monotonically decreasing, however, the electric intensity is monotonically increasing in nature. This solution gives us wide range of parameter for every positive value of n for which the solution is well behaved hence, suitable for modeling of super dense stars. Keeping in view of well behaved nature of this solution, one new class of solution is being studied extensively. Moreover, this class of solution gives us wide range of constant K (0≤K≤2.2) for which the solution is well behaved hence, suitable for modeling of super dense stars like strange quark stars, neutron stars and pulsars. For this class of solution the mass of a star is maximized with all degree of suitability, compatible with quark stars, neutron stars and pulsars. By assuming the surface density ρ _b =2×10¹⁴ g/cm³ (like, Brecher and Capocaso, Nature 259:377, 1976), corresponding to K=0 with X=0..235, the resulting well behaved model has the mass M=4.03M _Θ , radius r _b =19.53 km and moment of inertia I=1.213×10⁴⁶ g cm²; for K=1.5 with X=0.235, the resulting well behaved model has the mass M=4.43M _Θ , radius r _b =18.04 km and moment of inertia I=1.136×10⁴⁶ g cm²; for K=2.2 with X=0.235, the resulting well behaved model has the mass M=4.56M _Θ , radius r _b =17.30 km and moment of inertia I=1.076×10⁴⁶ g cm². These values of masses and moment of inertia are found to be consistent with the crab pulsars.