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arXiv · 1607.05600

Gravitomagnetic effect in magnetized neutron stars

Debarati Chatterjee·Chandrachur Chakraborty·Debades Bandyopadhyay
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Abstract

Rotating bodies in General Relativity produce frame dragging, also known as the {\it gravitomagnetic effect} in analogy with classical electromagnetism. In this work, we study the effect of magnetic field on the gravitomagnetic effect in neutron stars with poloidal geometry, which is produced as a result of its rotation. We show that the magnetic field has a non-negligible impact on frame dragging. The maximum effect of the magnetic field appears along the polar direction, where the frame-dragging frequency decreases with increase in magnetic field, and along the equatorial direction, where its magnitude increases. For intermediate angles, the effect of the magnetic field decreases, and goes through a minimum for a particular angular value at which magnetic field has no effect on gravitomagnetism. Beyond that particular angle gravitomagnetic effect increases with increasing magnetic field. We try to identify this `null region' for the case of magnetized neutron stars, both inside and outside, as a function of the magnetic field, and suggest a thought experiment to find the null region of a particular pulsar using the frame dragging effect.

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Debarati Chatterjee, Chandrachur Chakraborty, Debades Bandyopadhyay. 2016-07-19. Gravitomagnetic effect in magnetized neutron stars. https://doi.org/10.1088/1475-7516%2F2017%2F01%2F062

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