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arXiv · 1812.07657

(Self-)Magnetized Bose-Einstein Condensate stars

G. Quintero Angulo·A. Pérez Martínez·H. Pérez Rojas·D. Manreza Paret
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Abstract

We study magnetic field effects on the Equations of State (EoS) and the structure of Bose-Einstein Condensate (BEC) stars, i.e. a compact object composed by a gas of interacting spin one bosons formed up by the pairing of two neutrons. To include the magnetic field in the thermodynamic description, we suppose that particle-magnetic field and particle-particle interactions are independent. We consider two configurations for the magnetic field: one where it constant and externally fixed, and another where it is produced by the bosons by self-magnetization. Since the magnetic field produces the splitting of pressures in the directions along and perpendicular to the magnetic axis, stable configurations of self-magnetized and magnetized BEC stars are studied using the recently found $\gamma$-structure equations that describe axially symmetric objects. The magnetized BEC stars are, in general spheroidal, less massive and smaller than the non-magnetic ones, being these effects more relevant at low densities. For the self-magnetized BEC stars their inner profiles of magnetic field can be computed as a function of the equatorial radii. The values obtained for the core and surface magnetic fields are in agreement with those typical of compact objects.

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G. Quintero Angulo, A. Pérez Martínez, H. Pérez Rojas, D. Manreza Paret. 2018-12-18. (Self-)Magnetized Bose-Einstein Condensate stars. https://doi.org/10.1142/s0218271819501359

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