Accurate simulations of the dynamical barmode instability in full general relativity
Abstract
We present accurate simulations of the dynamical barmode instability in full general relativity focusing on two aspects which have not been investigated in detail in the past, namely, on the persistence of the bar deformation once the instability has reached its saturation and on the precise determination of the threshold for the onset of the instability in terms of the parameter {beta}=T/W. We find that generic nonlinear modecoupling effects appear during the development of the instability and these can severely limit the persistence of the bar deformation and eventually suppress the instability. In addition, we observe the dynamics of the instability to be strongly influenced by the value {beta} and on its separation from the critical value {beta}{sub c} marking the onset of the instability. We discuss the impact these results have on the detection of gravitational waves from this process and provide evidence that the classical perturbative analysis of the barmode instability for Newtonian and incompressible Maclaurin spheroids remains qualitatively valid and accurate also in full general relativity.
 Authors:
 MaxPlanckInstitut fuer Gravitationsphysik, AlbertEinsteinInstitut, Golm (Germany)
 Dipartimento di Fisica, Universita di Parma and INFN, Parma (Italy)
 (Italy)
 (United States)
 Publication Date:
 OSTI Identifier:
 21011088
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevD.75.044023; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; COMPUTERIZED SIMULATION; COSMOLOGY; COUPLING; DEFORMATION; GENERAL RELATIVITY THEORY; GRAVITATIONAL WAVES; NONLINEAR PROBLEMS
Citation Formats
Baiotti, Luca, Pietri, Roberto De, Manca, Gian Mario, Rezzolla, Luciano, SISSA, International School for Advanced Studies and INFN, Trieste, and Department of Physics, Louisiana State University, Baton Rouge. Accurate simulations of the dynamical barmode instability in full general relativity. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.044023.
Baiotti, Luca, Pietri, Roberto De, Manca, Gian Mario, Rezzolla, Luciano, SISSA, International School for Advanced Studies and INFN, Trieste, & Department of Physics, Louisiana State University, Baton Rouge. Accurate simulations of the dynamical barmode instability in full general relativity. United States. doi:10.1103/PHYSREVD.75.044023.
Baiotti, Luca, Pietri, Roberto De, Manca, Gian Mario, Rezzolla, Luciano, SISSA, International School for Advanced Studies and INFN, Trieste, and Department of Physics, Louisiana State University, Baton Rouge. Thu .
"Accurate simulations of the dynamical barmode instability in full general relativity". United States.
doi:10.1103/PHYSREVD.75.044023.
@article{osti_21011088,
title = {Accurate simulations of the dynamical barmode instability in full general relativity},
author = {Baiotti, Luca and Pietri, Roberto De and Manca, Gian Mario and Rezzolla, Luciano and SISSA, International School for Advanced Studies and INFN, Trieste and Department of Physics, Louisiana State University, Baton Rouge},
abstractNote = {We present accurate simulations of the dynamical barmode instability in full general relativity focusing on two aspects which have not been investigated in detail in the past, namely, on the persistence of the bar deformation once the instability has reached its saturation and on the precise determination of the threshold for the onset of the instability in terms of the parameter {beta}=T/W. We find that generic nonlinear modecoupling effects appear during the development of the instability and these can severely limit the persistence of the bar deformation and eventually suppress the instability. In addition, we observe the dynamics of the instability to be strongly influenced by the value {beta} and on its separation from the critical value {beta}{sub c} marking the onset of the instability. We discuss the impact these results have on the detection of gravitational waves from this process and provide evidence that the classical perturbative analysis of the barmode instability for Newtonian and incompressible Maclaurin spheroids remains qualitatively valid and accurate also in full general relativity.},
doi = {10.1103/PHYSREVD.75.044023},
journal = {Physical Review. D, Particles Fields},
number = 4,
volume = 75,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}

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