Investigating quark star properties through baryon number density $(n)$ within the framework of $f(Q)$ gravity

Sourav Biswas; Debadri Bhattacharjee; Pradip Kumar Chattopadhyay; Nawal H. Siddig; Euaggelos E. Zotos; Laila Abdulaziz Al-Essa

arXiv · 2603.12907

Investigating quark star properties through baryon number density $(n)$ within the framework of $f(Q)$ gravity

Sourav Biswas·Debadri Bhattacharjee·Pradip Kumar Chattopadhyay·Nawal H. Siddig·Euaggelos E. Zotos·Laila Abdulaziz Al-Essa

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Abstract

In this paper, we construct a viable strange star model in the framework of the equation of state, $p_r=\frac{1}{3}(\rho-4B)$, proposed in the MIT bag model, where $B$ is termed as the bag constant. Considering extreme Wood-Saxon-like parameterisation of baryon number density dependent Bag parameter $(B)$ in the framework of $f(Q)$ modified gravity. We have determined the possible range of baryon number density ($n$) for stable quark matter inside the star and calculated the corresponding range of $B$. By solving TOV equations, we obtain the possible maximum mass and radius considering the MIT bag model equation of state with baryon number density dependent $B$. All the physical parameters associated with the stars, such as $\rho,~p_r,~p_t$ and anisotropy parameter ($\Delta$), have been analysed in this model to establish the physical viability as well as acceptability of the model. Then, we study the stability of the model by analysing the causality conditions, energy conditions, generalised TOV equation, cracking condition of Herrera and the study of adiabatic index of the fluid. Within the parameter space used here to construct the model, we have predicted the radii of a few known compact stars, and it is found that the model is suitable in predicting the radii of stars where masses lie below the $2.46~M\odot$, and the predicted radii from the model are nearly equal to the values obtained from recent observations. It is significant to observe that up to $2.01~M\odot$, it may be treated as a Strange Star (SS). On the other hand, maximum mass above $2.01~M\odot$ and up to $2.46~M\odot$ may be treated as di-quark stars.

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BibTeX RIS

Sourav Biswas, Debadri Bhattacharjee, Pradip Kumar Chattopadhyay, Nawal H. Siddig, Euaggelos E. Zotos, Laila Abdulaziz Al-Essa. 2026-03-13. Investigating quark star properties through baryon number density $(n)$ within the framework of $f(Q)$ gravity. https://arxiv.org/abs/2603.12907

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