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arXiv · 2507.11956

Investigating Universal Relations in Compact Stars featuring $\Delta-$Admixed Exotic Dense Matter

Vivek Baruah Thapa·Anil Kumar·Vishal Parmar·Monika Sinha
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Abstract

The dense material in a compact star from a supernova remnant is beyond terrestrial experimentation, so phenomenological modeling is used to match astrophysical observations. This is crucial due to the complex sensitivity of compact star features to dense matter properties. Despite modeling flexibility, certain universal relationships among compact star features hold true, regardless of the matter model. Our study examines these universal relationships, focusing on the moment of inertia, tidal Love number, and quadrupole moment, as well as correlations between non-radial oscillation frequencies and star compactness. We consider baryonic stars with cores of heavier baryons. Our findings show that baryonic stars with cores of heavier baryons follow the universal relations, and the f-mode oscillation frequency's universality relative to tidal deformability is notable, with an error margin under 1$\%$.

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Vivek Baruah Thapa, Anil Kumar, Vishal Parmar, Monika Sinha. 2025-07-16. Investigating Universal Relations in Compact Stars featuring $\Delta-$Admixed Exotic Dense Matter. https://doi.org/10.1016/j.jspc.2025.100084

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