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arXiv · 1101.4875

Magnetic field generated by r-modes in accreting quark stars

L. Bonanno·C. Cuofano·A. Drago·G. Pagliara·J. Schaffner-Bielich
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Abstract

We show that the r-mode instability can generate strong toroidal fields in the core of accreting millisecond quark stars by inducing differential rotation. We follow the spin frequency evolution on a long time scale taking into account the magnetic damping rate in the evolution equations of r-modes. The maximum spin frequency of the star is only marginally smaller than in the absence of the magnetic field. The late-time evolution of the stars which enter the r-mode instability region is instead rather different if the generated magnetic fields are taken into account: they leave the millisecond pulsar region and they become radio pulsars.

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L. Bonanno, C. Cuofano, A. Drago, G. Pagliara, J. Schaffner-Bielich. 2011-01-25. Magnetic field generated by r-modes in accreting quark stars. https://doi.org/10.1051/0004-6361/201116661

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