Determination of the charge for strange stars

Abstract

Beginning from the proposal of a physically acceptable model to represent the interior of compact stars, in which their interior is formed by a strange matter distribution described by a charged fluid with anisotropic pressure, a MIT Bag equation of state for the radial pressure and metric functions given by a geometry that describes a regular, static and spherically symmetric space-time, we will determine the possible charge of some strange stars, or candidates, for which we know their radius and mass in an observational manner. As are: EXO 1785-248, SAX J1808.4-3658, SMC X-1, LMC X-4, Her X-1 and 4U 1538-52. The values of the Bag constant, B g , are found between 119.8 Mev/fm3 and 176.41 Mev/fm3. Meanwhile the interval of the electric charge is found between 1.5453 × 1018 C and 7.6271 × 1019 C, the minimum corresponds to the star Her X-1 and the maximum to the star SMCX-1. Also, we show that for each fixed value of compactness u = GM/c 2 R, we obtain that, for greater values of the Bag constant the net charge diminishes and as the compactness increases the associated Bag constant increases as well.