Magnetic-Field Induced Deformation in Hybrid Stars

Ishfaq A. Rather, Asloob A. Rather, V. Dexheimer, Ilídio Lopes, A. A. Usmani, S. K. Patra

Submitted on 13 September 2022


The effects of strong magnetic fields on the deconfinement phase transition expected to take place in the interior of massive neutron stars is studied in detail for the first time. For hadronic matter, the very general density-dependent relativistic mean-field (DD-RMF) model is employed, while the simple, but effective Vector-Enhanced Bag model (vBag) model is used to study quark matter. Magnetic-field effects are incorporated into the matter equation of state and in the general-relativity solutions, which also satisfy Maxwell's equations. We find that, for large values of magnetic dipole moment, the maximum mass, canonical-mass radius, and dimensionless tidal deformability obtained for stars using spherically-symmetric TOV equations and axisymmetric solutions attained through the LORENE library differ considerably. The deviations depend on the stiffness of the equation of state and on the star mass being analyzed. This points to the fact that, unlike what was assumed previously in the literature, magnetic field thresholds for the correct assumption of isotropic stars and the proper use of TOV equations depend on the matter composition and interactions.


Comment: 15 pages, 7 figures

Subjects: Nuclear Theory; Astrophysics - High Energy Astrophysical Phenomena