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arXiv · 2509.11665

A study of the pulsar EXO 1745-248 in $f(Q)$ gravity with pseudo-spheroidal geometry

Bibhash Das·Bikash Chandra Paul
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Abstract

We present a singularity-free relativistic interior solution for constructing stable quark stellar models in the framework of a linear $f(Q)$ gravity ($f(Q) = \alpha Q + \phi$) satisfying the pseudo-spheroidal geometry. The physical features and the stability of the stellar model is explored with strange star (SS) candidate EXO 1745-248 ($M = 1.7\, M_{\odot}$ and $R = 9\, km$). The Durgapal-Banerjee transformation is employed to obtain the relativistic interior solution using the MIT Bag model equation of state (EoS): $P = \frac{1}{3}(\rho - 4 B_{g})$. For a linear form of $f(Q)$ gravity, we obtain the exterior vacuum solution, which reduces to the Schwarzschild-de Sitter (SdS) solution with the cosmological constant term, $\Lambda = \frac{\phi}{2\alpha}$. The stellar model is analyzed for the different values of the spheroidicity parameter ($\mu$). The value of $\alpha$ is constrained using a viable physical limit on the Bag parameter ($B_{g} \in [57.55,95.11]\,MeV\,fm^{-3}$). The constraints on Mass-Radius relation indicates that physically acceptable SS models are permitted for $\mu \geq 7$. The contribution of $\mu$ to the energy density, pressure profiles, and other physical features is studied for the SS candidate EXO 1745-248. The stability of the stellar model obtained here is also analyzed through causality condition, adiabatic index and other stability criteria. We also investigate the stellar model for other SS candidates to test its viability. The relativistic interior solution obtained here can be used to construct viable and physically acceptable strange star models with very high compactness ratio in the framework of linear $f(Q)$ gravity.

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Bibhash Das, Bikash Chandra Paul. 2025-09-15. A study of the pulsar EXO 1745-248 in $f(Q)$ gravity with pseudo-spheroidal geometry. https://arxiv.org/abs/2509.11665

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