Neutron Star Pulsations and Instabilities

Abstract

Gravitational radiation (GR) drives an instability in certain modes of rotating stars. This instability is strong enough in the case of the r-modes to cause their amplitudes to grow on a timescale of tens of seconds in rapidly rotating neutron stars. GR emitted by these modes removes angular momentum from the star at a rate which would spin it down to a relatively small angular velocity within about one year, if the dimensionless amplitude of the mode grows to order unity. A pedagogical level discussion is given here on the mechanism of GR instability in rotating stars, on the relevant properties of the r-modes, and on our present understanding of the dissipation mechanisms that tend to suppress this instability in neutron stars. The astrophysical implications of this GR driven instability are discussed for young neutron stars, and for older systems such as low mass x-ray binaries. Recent work on the non-linear evolution of the r-modes is also presented.

To appear in "Gravitational Waves: A Challenge to Theoretical Astrophysics," edited by V. Ferrari, J.C. Miller, and L. Rezzolla (ICTP, Lecture Notes Series)

Cited by in corpus (9)

• Strange Quark Matter and Compact Stars
• Rotating Stars in Relativity
• Rotating Stars in Relativity
• Strange stars as persistent sources of gravitational waves
• Dense matter in compact stars - A pedagogical introduction
• Bulk viscosities of a cold relativistic superfluid: color-flavor locked quark matter
• Bulk viscosity coefficients due to phonons in superfluid neutron stars
• Dissipative superfluids, from cold atoms to quark matter
• Effects of the nuclear equation of state on the r-mode instability and evolution of neutron stars