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arXiv · 2402.12328

Observations of compact stars and fermion-boson stars with a quartic self-interaction

Susana Valdez-Alvarado·Alejandro Cruz-Osorio·J. M. Dávila·L. Arturo Ureña-López·Ricardo Becerril
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Abstract

We investigated the possibility that compact stars could be described by a fermion-boson star with a quartic self-interaction in the boson sector. Specifically, by varying the polytropic constant $K$ and adiabatic index $\Gamma$ in the polytropic equation of state, the boson mass $\mu$, and the self-interaction parameter $\Lambda$, we construct equilibrium configurations of these mixed-stars with total mass compatible with the mass constraints obtained from observational data of the collaborations NICE, NICER/XMN-Newton, and LIGO. Our work confirms that the addition of a boson sector eases the comparison of neutron star models with gravitational events related to compact objects and that in such a case observations may have preference for a positive self-interaction in the boson sector.

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Susana Valdez-Alvarado, Alejandro Cruz-Osorio, J. M. Dávila, L. Arturo Ureña-López, Ricardo Becerril. 2024-02-19. Observations of compact stars and fermion-boson stars with a quartic self-interaction. https://arxiv.org/abs/2402.12328

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