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arXiv · 2407.01932

Study of Anisotropic Compact Stars in $f(\mathcal{R},\mathcal{T},\mathcal{R}_{\chi\xi}\mathcal{T}^{\chi\xi})$ Gravity

M. Sharif·T. Naseer
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Abstract

This paper aims to examine the composition of various spherically symmetric star models which are coupled with anisotropic configuration in $f(\mathcal{R},\mathcal{T},\mathcal{Q})$ gravity, where $\mathcal{Q}=\mathcal{R}_{\chi\xi}\mathcal{T}^{\chi\xi}$. We discuss the physical features of compact objects by employing bag model equation of state and construct the modified field equations in terms of Krori-Barua ansatz involving unknowns ($A,B,C$). The observational data of 4U 1820-30,~Vela X-I,~SAX J 1808.4-3658,~RXJ 1856-37 and Her X-I is used to calculate these unknowns and bag constant $\mathfrak{B_c}$. Further, we observe the behavior of energy density, radial and tangential pressure as well as anisotropy through graphical interpretation for a viable model $\mathcal{R}+\varrho\mathcal{Q}$ of this gravity. For a particular value of the coupling constant $\varrho$, we study the behavior of mass, compactness, redshift and the energy bounds. The stability of the considered stars is also checked by using two criteria. We conclude that our developed structure in this gravity is in well-agreement with all the physical requirements.

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M. Sharif, T. Naseer. 2024-07-02. Study of Anisotropic Compact Stars in $f(\mathcal{R},\mathcal{T},\mathcal{R}_{\chi\xi}\mathcal{T}^{\chi\xi})$ Gravity. https://doi.org/10.1007/s12043-022-02357-4

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