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arXiv · 2407.10587

Charged analogues of singularity-free anisotropic compact stars under linear $f(Q)$-action

Debadri Bhattacharjee·Pradip Kumar Chattopadhyay
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Abstract

This study simulates the characteristics of spherically symmetric, anisotropic compact stellar bodies with electrical charge within the framework of the $f(Q)$ theory of gravity. Employing the Krori-Barua metric ansatz (K.D. Krori, J. Barua, J. Phys. A: Math. Gen. 8 (1975) 508) along with a linear form of $f(Q)$ model, {\it viz.}, $f(Q)=\alpha_{0}+\alpha_{1}Q$, we obtain a tractable set of exact relativistic solutions of the field equations. A specific form of charge $(q=q_{0}r^{3})$ is considered here for the present analysis. It is noted that the model is valid up to the value of charge intensity $q_{0}\leq0.0009~Km^{-2}$. Beyond this value, the model does not permit physically viable results. We have obtained the best fit equation of state in the model, which is incorporated to solve the TOV equations numerically to determine the mass-radius relation within the parameter space used here. With increasing charge intensity $(q_{0})$ from 0.0002 to 0.0009, the maximum mass ranges from $2.84-2.92~M_{\odot}$, and the corresponding radii range from $12.00-12.20~Km$. Moreover, the predicted radii of some recently observed pulsars and GW 190814 show that our model also complies with the estimated radii based on the observational results. Our model is found to satisfy all the characteristic features, such as behaviour of matter variables, causality condition, energy constraints and stability criteria, which are pertinent in the context of a stable stellar configuration to emerge as a viable and physically acceptable stellar model in the framework of $f(Q)$ gravity.

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Debadri Bhattacharjee, Pradip Kumar Chattopadhyay. 2024-07-15. Charged analogues of singularity-free anisotropic compact stars under linear $f(Q)$-action. https://arxiv.org/abs/2407.10587

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