### Abstract

We investigate the instability driven by viscosity in rotating relativistic stars by means of an iterative approach. We focus on polytropic rotating equilibrium stars and impose an m=2 perturbation in the lapse. We vary both the stiffness of the equation of state and the compactness of the star to study these factors on the critical value T/W for the instability. For a rigidly rotating star, the criterion T/W, where T is the rotational kinetic energy and W the gravitational binding energy, mainly depends on the compactness of the star and takes values around 0.13-0.16, which slightly differ from that of Newtonian incompressible stars (∼0.14). For differentially rotating stars, the critical value of T/W is found to span the range 0.17-0.25. The value is significantly larger than in the rigidly rotating case with the same compactness of the star. Finally we discuss the possibility of detecting gravitational waves from viscosity-driven instabilities using ground-based interferometers.

Original language | English |
---|---|

Title of host publication | Isolated Neutron Stars: From The Surface To The Interior |

Publisher | Springer Netherlands |

Pages | 481-485 |

Number of pages | 5 |

ISBN (Print) | 9781402059971 |

DOIs | |

Publication status | Published - 2007 |

Externally published | Yes |

### Fingerprint

### Keywords

- Gravitational waves
- Instabilities
- Relativity
- Stars: rotation

### ASJC Scopus subject areas

- Physics and Astronomy(all)

### Cite this

*Isolated Neutron Stars: From The Surface To The Interior*(pp. 481-485). Springer Netherlands. https://doi.org/10.1007/978-1-4020-5998-8-62

**Instabilities in rotating relativistic stars driven by viscosity.** / Saijo, Motoyuki; Gourgoulhon, Eric.

Research output: Chapter in Book/Report/Conference proceeding › Chapter

*Isolated Neutron Stars: From The Surface To The Interior.*Springer Netherlands, pp. 481-485. https://doi.org/10.1007/978-1-4020-5998-8-62

}

TY - CHAP

T1 - Instabilities in rotating relativistic stars driven by viscosity

AU - Saijo, Motoyuki

AU - Gourgoulhon, Eric

PY - 2007

Y1 - 2007

N2 - We investigate the instability driven by viscosity in rotating relativistic stars by means of an iterative approach. We focus on polytropic rotating equilibrium stars and impose an m=2 perturbation in the lapse. We vary both the stiffness of the equation of state and the compactness of the star to study these factors on the critical value T/W for the instability. For a rigidly rotating star, the criterion T/W, where T is the rotational kinetic energy and W the gravitational binding energy, mainly depends on the compactness of the star and takes values around 0.13-0.16, which slightly differ from that of Newtonian incompressible stars (∼0.14). For differentially rotating stars, the critical value of T/W is found to span the range 0.17-0.25. The value is significantly larger than in the rigidly rotating case with the same compactness of the star. Finally we discuss the possibility of detecting gravitational waves from viscosity-driven instabilities using ground-based interferometers.

AB - We investigate the instability driven by viscosity in rotating relativistic stars by means of an iterative approach. We focus on polytropic rotating equilibrium stars and impose an m=2 perturbation in the lapse. We vary both the stiffness of the equation of state and the compactness of the star to study these factors on the critical value T/W for the instability. For a rigidly rotating star, the criterion T/W, where T is the rotational kinetic energy and W the gravitational binding energy, mainly depends on the compactness of the star and takes values around 0.13-0.16, which slightly differ from that of Newtonian incompressible stars (∼0.14). For differentially rotating stars, the critical value of T/W is found to span the range 0.17-0.25. The value is significantly larger than in the rigidly rotating case with the same compactness of the star. Finally we discuss the possibility of detecting gravitational waves from viscosity-driven instabilities using ground-based interferometers.

KW - Gravitational waves

KW - Instabilities

KW - Relativity

KW - Stars: rotation

UR - http://www.scopus.com/inward/record.url?scp=84892839304&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84892839304&partnerID=8YFLogxK

U2 - 10.1007/978-1-4020-5998-8-62

DO - 10.1007/978-1-4020-5998-8-62

M3 - Chapter

AN - SCOPUS:84892839304

SN - 9781402059971

SP - 481

EP - 485

BT - Isolated Neutron Stars: From The Surface To The Interior

PB - Springer Netherlands

ER -