Charged anisotropic strange stars in Brans-Dicke gravity with a massive scalar field through embedding approach

TL;DR

This paper models charged anisotropic strange stars within Brans-Dicke gravity incorporating a massive scalar field, using an embedding approach to derive solutions consistent with physical stability and observational data.

Contribution

It introduces a novel solution framework for charged anisotropic stars in Brans-Dicke gravity with a massive scalar field, emphasizing the effects of scalar and electric fields on stellar properties.

Findings

Scalar field increases surface charge density.

Scalar and electric fields influence mass-radius relation.

Models match observed properties of specific compact stars.

Abstract

In this exposition, we seek solutions of the Einstein-Maxwell field equations in the presence of a massive scalar field cast in the Brans-Dicke (BD) formalism which describes charged anisotropic strange stars. The interior spacetime is described by a spherically symmetric static metric of embedding class I. This reduces the problem to a single-generating function of the metric potential which is chosen by appealing to physics based on regularity at each interior point of the stellar interior. The resulting model is subjected to rigorous physical checks based on stability, causality and regularity. We show that our solutions describe compact objects such as PSR J1903+327; Cen X-3; EXO 1785-248 \& LMC X-4 to an excellent approximation. Novel results of our investigation reveal that the scalar field leads to higher surface charge densities which in turn affects the compactness and upper and lower values imposed by the modified Buchdahl limit for charged stars. Our results also show that the electric and scalar fields which originate from entirely different sources couple to alter physical characteristics such as mass-radius relation and surface redshift of compact objects. This superposition of the electric and scalar fields is enhanced by an increase in the BD coupling constant, $\omega_{BD}$.