A comprehensive study is carried out on the impact of strong magnetic fields on the deconfinement phase transition inside massive neutron stars. The matter equation of state and the general relativity solutions, which also fulfill Maxwell’s equations, are modified when taking magneticfield effects into account. We observe that the maximum mass and canonicalmass radius of stars computed using sphericallysymmetric TOV equations and axisymmetric solutions obtained through the LORENE library differ significantly for large values of magnetic dipole moment. The discrepancies depend on the stellar mass being studied, as well as the stiffness of the equation of state. This indicates that the matter composition and interactions determine the magnetic field thresholds for the acceptable approximation of isotropic stars and the appropriate application of TOV equations.
The effects of strong magnetic fields on the deconfinement phase transition expected to take place in the interior of massive neutron stars are studied in detail for the first time. For hadronic matter, the very general densitydependent relativistic mean field model is employed, while the simple, but effective vectorenhanced bag model is used to study quark matter. Magneticfield effects are incorporated into the matter equation of state and in the generalrelativity 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 Tolman–Oppenheimer–Volkoff (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 approximation of isotropic stars and the acceptable use of TOV equations depend on the matter composition and interactions.
more » « less Award ID(s):
 1748621
 NSFPAR ID:
 10392762
 Publisher / Repository:
 DOI PREFIX: 10.3847
 Date Published:
 Journal Name:
 The Astrophysical Journal
 Volume:
 943
 Issue:
 1
 ISSN:
 0004637X
 Format(s):
 Medium: X Size: Article No. 52
 Size(s):
 Article No. 52
 Sponsoring Org:
 National Science Foundation
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