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Non-Linear Evolution of the r-Modes in Neutron Stars

Lee Lindblom·Joel E. Tohline·Michele Vallisneri
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Abstract

The evolution of a neutron-star r-mode driven unstable by gravitational radiation (GR) is studied here using numerical solutions of the full non-linear fluid equations. The amplitude of the mode grows to order unity before strong shocks develop which quickly damp the mode. In this simulation the star loses about 40% of its initial angular momentum and 50% of its rotational kinetic energy before the mode is damped. The non-linear evolution causes the fluid to develop strong differential rotation which is concentrated near the surface and especially near the poles of the star.

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Lee Lindblom, Joel E. Tohline, Michele Vallisneri. 2001-02-02. Non-Linear Evolution of the r-Modes in Neutron Stars. https://doi.org/10.1103/physrevlett.86.1152

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