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arXiv · 0903.0349

Magnetic fields generated by r-modes in accreting millisecond pulsars

Carmine Cuofano·Alessandro Drago
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Abstract

In millisecond pulsars the existence of the Coriolis force allows the development of the so-called Rossby oscillations (r-modes) which are know to be unstable to emission of gravitational waves. These instabilities are mainly damped by the viscosity of the star or by the existence of a strong magnetic field. A fraction of the observed millisecond pulsars are known to be inside Low Mass X-ray Binaries (LMXBs), systems in which a neutron star (or a black hole) is accreting from a donor whose mass is smaller than 1 $M_\odot$. Here we show that the r-mode instabilities can generate strong toroidal magnetic fields by inducing differential rotation. In this way we also provide an alternative scenario for the origin of the magnetars.

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Carmine Cuofano, Alessandro Drago. 2009-03-02. Magnetic fields generated by r-modes in accreting millisecond pulsars. https://doi.org/10.1088/1742-6596/168/1/012008

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