English

R-mode runaway and rapidly rotating neutron stars

Astrophysics 2009-10-31 v2 General Relativity and Quantum Cosmology

Abstract

We present a simple spin evolution model that predicts that rapidly rotating accreting neutron stars will mainly be confined to a narrow range of spin-frequencies; P= 1.5-5 ms. This is in agreement with current observations of both neutron stars in the Low-Mass X-ray Binaries and millisecond radiopulsars. The main ingredients in the model are; i) the instability of r-modes above a critical spin rate, ii) thermal runaway due to heat released as viscous damping mechanisms counteract the r-mode growth, and iii) a revised estimate of the strength of dissipation due to the presence of a viscous boundary layer at the base of the crust in an old and relatively cold neutron star. We discuss the gravitational waves that are radiated during the brief r-mode driven spin-down phase. We also briefly touch on how the new estimates affects the predicted initial spin periods of hot young neutron stars.

Keywords

Cite

@article{arxiv.astro-ph/0002114,
  title  = {R-mode runaway and rapidly rotating neutron stars},
  author = {N. Andersson and D. I. Jones and K. D. Kokkotas and N. Stergioulas},
  journal= {arXiv preprint arXiv:astro-ph/0002114},
  year   = {2009}
}

Comments

5 pages incl. 2 figures, minor changes, accepted for publication in ApJ Letters