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Register a new userObservables of spheroidal magnetized Strange Stars
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Aurora Perez Martinez Prof
Publication date
2020
fields
Physics
and research's language is
English
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We study stable spheroidal configurations of magnetized Strange Stars using an axially symmetric metric in spherical coordinates that uses a gamma parameter to link the anisotropy in the Equation of State due to the magnetic field with the deformation of the star. The stars are composed by magnetized Strange Quark Matter described within the framework of the MIT-Bag model. Their masses, radii, eccentricity, redshift and mass quadrupole moment are computed. Results are compared with spherical Strange Stars solutions obtained with TOV equations and observational data of Strange Stars candidates. In the spheroidal model the observables depend directly on the deformation of the stars, and even though it is small, the observables strongly deviate from the corresponding spherical configurations. Thus, the highest values of the mass quadrupole moment correspond to the intermediate mass regime. These differences might allow to discriminate between models with/without magnetic field when compared with observations.
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We investigate the properties of anisotropic, spherically symmetric compact stars, especially neutron stars and strange quark stars, made of strongly magnetized matter. The neutron stars are described by SLy equation of state, the strange quark stars by an equation of state based on the MIT Bag model. The stellar models are based on an a priori assumed density dependence of the magnetic field and thus anisotropy. Our study shows that not only the presence of a strong magnetic field and anisotropy, but also the orientation of the magnetic field itself, have an important influence on the physical properties of stars. Two possible magnetic field orientations are considered, a radial orientation, where the local magnetic fields point in the radial direction, and a transverse orientation, where the local magnetic fields are perpendicular to the radial direction. Interestingly, we find that for a transverse orientation of the magnetic field, the stars become more massive with increasing anisotropy and magnetic field strength and increase in size, since the repulsive, effective anisotropic force increases in this case. In the case of a radially orientated magnetic field, however, the masses and radii of the stars decrease with increasing magnetic field strength, because of the decreasing effective anisotropic force. Importantly, we also show that in order to achieve hydrostatic equilibrium configurations of magnetized matter, it is essential to account for both the local anisotropy effects as well as the anisotropy effects caused by a strong magnetic field. Otherwise, hydrostatic equilibrium is not achieved for magnetized stellar models.
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