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arXiv · 0709.0403

Unstable g-modes in Proto-Neutron Stars

V. Ferrari·L. Gualtieri·J. A. Pons
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Abstract

In this article we study the possibility that, due to non-linear couplings, unstable g-modes associated to convective motions excite stable oscillating g-modes. This problem is of particular interest, since gravitational waves emitted by a newly born proto-neutron star pulsating in its stable g-modes would be in the bandwidth of VIRGO and LIGO. Our results indicate that nonlinear saturation of unstable modes occurs at relatively low amplitudes, and therefore, even if there exists a coupling between stable and unstable modes, it does not seem to be sufficiently effective to explain, alone, the excitation of the oscillating g-modes found in hydrodynamical simulations.

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V. Ferrari, L. Gualtieri, J. A. Pons. 2007-09-04. Unstable g-modes in Proto-Neutron Stars. https://doi.org/10.1088/0264-9381%2F24%2F20%2F011

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