Low T/|W| dynamical instabilities in differentially rotating stars: Diagnosis with canonical angular momentum

Motoyuki Saijo, Shin'Ichirou Yoshida

Research output: Chapter in Book/Report/Conference proceedingConference contribution

2 Citations (Scopus)

Abstract

We study the nature of non-axisymmetric dynamical instabilities in differentially rotating stars with both linear eigenmode analysis and hydrodynamic simulations in Newtonian gravity. We especially investigate the following three types of instability; the one-armed spiral instability, the low T/|W| bar instability, and the high T/|W| bar instability, where T is the rotational kinetic energy and W is the gravitational potential energy. The nature of the dynamical instabilities is clarified by using a canonical angular momentum as a diagnostic. We find that the one-armed spiral and the low T/|W| bar instabilities occur around the corotation radius, and they grow through the inflow of canonical angular momentum around the corotation radius. The result is a clear contrast to that of a classical dynamical bar instability in high T/|W|. We also discuss the feature of gravitational waves generated from these three types of instability.

Original languageEnglish
Title of host publicationAIP Conference Proceedings
Pages728-735
Number of pages8
Volume861
DOIs
Publication statusPublished - 2006
Externally publishedYes
EventAlbert Einstein Century International Conference - Paris
Duration: 2005 Jul 182005 Jul 22

Other

OtherAlbert Einstein Century International Conference
CityParis
Period05/7/1805/7/22

Fingerprint

angular momentum
stars
corotation
radii
gravitational waves
gravitational fields
kinetic energy
potential energy
hydrodynamics
gravitation
simulation

Keywords

  • Gravitational waves
  • Hydrodynamics
  • Instabilities
  • Stars: Evolution
  • Stars: Oscillation
  • Stars: Rotation

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Low T/|W| dynamical instabilities in differentially rotating stars : Diagnosis with canonical angular momentum. / Saijo, Motoyuki; Yoshida, Shin'Ichirou.

AIP Conference Proceedings. Vol. 861 2006. p. 728-735.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Saijo, M & Yoshida, SI 2006, Low T/|W| dynamical instabilities in differentially rotating stars: Diagnosis with canonical angular momentum. in AIP Conference Proceedings. vol. 861, pp. 728-735, Albert Einstein Century International Conference, Paris, 05/7/18. https://doi.org/10.1063/1.2399650
Saijo, Motoyuki ; Yoshida, Shin'Ichirou. / Low T/|W| dynamical instabilities in differentially rotating stars : Diagnosis with canonical angular momentum. AIP Conference Proceedings. Vol. 861 2006. pp. 728-735
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