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arXiv · 2501.10730

Braneworld Neutron Stars: Constraining Brane Tension with Observational Data

Abstract

In this article, we investigate the properties of neutron stars within the braneworld model, employing six distinct piece-wise polytropic equation of states. These equation of states satisfy observational constraints put by GW170817 event and pulsar observations (PSR J0740 and PSR J0030) within general relativity framework. Our primary goal is to assess whether these equation of states, in conjunction with the braneworld framework, can accommodate more massive neutron stars, as suggested by the GW190814 observation, while remaining consistent with established observational constraints. The brane tension parameter significantly affects the mass-radius and mass-tidal deformability relations, particularly for neutron stars with masses exceeding the canonical value. We establish strong constraints on the brane tension by comparing the canonical neutron star radius and tidal deformability with the results from the braneworld model, a stringent lower bound on the brane tension, $\lambda > 2 \times 10^ {37} \, \text {dyne/cm} ^2 $. Our results demonstrate that the braneworld model allows for the existence of neutron stars with masses greater than those predicted by General Relativity, in agreement with the GW190814 observation, and highlight the significant role of brane tension in shaping the properties of neutron stars.

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BibTeXRIS

Masum Murshid, Nilofar Rahman, Mehedi Kalam. 2025-01-18. Braneworld Neutron Stars: Constraining Brane Tension with Observational Data. https://arxiv.org/abs/2501.10730

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