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Magnetic collapse of a neutron gas: Can magnetars indeed be formed

A. Perez Martinez·H. Perez Rojas·H. J. Mosquera Cuesta
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Abstract

A relativistic degenerate neutron gas in equilibrium with a background of electrons and protons in a magnetic field exerts its pressure anisotropically, having a smaller value perpendicular than along the magnetic field. For critical fields the magnetic pressure may produce the vanishing of the equatorial pressure of the neutron gas. Taking it as a model for neutron stars, the outcome could be a transverse collapse of the star. This fixes a limit to the fields to be observable in stable neutron star pulsars as a function of their density. The final structure left over after the implosion might be a mixed phase of nucleons and meson condensate, a strange star, or a highly distorted black hole or black "cigar", but no any magnetar, if viewed as a super strongly magnetized neutron star. However, we do not exclude the possibility of a supersotrong magnetic fields arising in supernova explosions which lead directly to strange stars. In other words, if any magnetars exist, they cannot be neutron stars.

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A. Perez Martinez, H. Perez Rojas, H. J. Mosquera Cuesta. 2003-03-13. Magnetic collapse of a neutron gas: Can magnetars indeed be formed. https://doi.org/10.1140/epjc%2Fs2003-01192-6

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