English

The Innermost Stable Circular Orbit in Compact Binaries

General Relativity and Quantum Cosmology 2009-11-07 v1 Astrophysics

Abstract

Newtonian point mass binaries can be brought into arbitrarily close circular orbits. Neutron stars and black holes, however, are extended, relativistic objects. Both finite size and relativistic effects make very close orbits unstable, so that there exists an innermost stable circular orbit (ISCO). We illustrate the physics of the ISCO in a simple model problem, and review different techniques which have been employed to locate the ISCO in black hole and neutron star binaries. We discuss different assumptions and approximations, and speculate on how differences in the results may be explained and resolved.

Keywords

Cite

@article{arxiv.gr-qc/0101045,
  title  = {The Innermost Stable Circular Orbit in Compact Binaries},
  author = {Thomas W. Baumgarte},
  journal= {arXiv preprint arXiv:gr-qc/0101045},
  year   = {2009}
}

Comments

13 pages, 2 figures, to appear in "Astrophysical Sources of Gravitational Radiation", edited by J. M. Centrella (AIP Press)