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arXiv · 1201.4455

Orbital Ferromagnetism and the Chandrasekhar Mass-Limit

M. Akbari-Moghanjoughi
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Abstract

In this paper, using both quantum magnetohydrodynamic (MHD) and magnetohydrostatic (MHS) models of a relativistically degenerate magnetic compact star, the fundamental role of Landau orbital ferromagnetism (LOFER) on the magneto-gravitational stability of such star is revealed. It is shown that the previously suggested magnetic equation of state for LOFER with some generalization of form $B=\beta \rho^{2s/3}$ only within the range $0\leq s\leq 1$ and $0\leq \beta< \sqrt{2\pi}$ leads to magneto-gravitational stability with distinct critical value $\beta_{cr}=\sqrt{2\pi}$ governing the magnetohydrostatic stability of the compact star. Furthermore, the value of the parameters $s$ and $\beta$ is shown to fundamentally control both the quantum and Chandrasekhar gravitational collapse mechanisms and the previously discovered mass-limit on white dwarfs. Current findings can help to understand the origin of magnetism and its inevitable role on the stability of the relativistically degenerate super-dense magnetized matter encountered in many white-dwarfs and neutron stars.

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M. Akbari-Moghanjoughi. 2012-01-21. Orbital Ferromagnetism and the Chandrasekhar Mass-Limit. https://doi.org/10.1063/1.4714611

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