Gravitational waves from nonlinear couplings of radial and polar nonradial modes in relativistic stars
Abstract
The postbounce oscillations of newlyborn relativistic stars are expected to lead to gravitationalwave emission through the excitation of nonradial oscillation modes. At the same time, the star is oscillating in its radial modes, with a central density variation that can reach several percent. Nonlinear couplings between radial oscillations and polar nonradial modes lead to the appearance of combination frequencies (sums and differences of the linear mode frequencies). We study such combination frequencies using a gaugeinvariant perturbative formalism, which includes bilinear coupling terms between different oscillation modes. For typical values of the energy stored in each mode we find that gravitational waves emitted at combination frequencies could become detectable in galactic corecollapse supernovae with advanced interferometric or wideband resonant detectors.
 Authors:
 Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)
 Dipartimento di Fisica, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin (Italy) and INFN, Sezione di Torino, Via Pietro Giuria 1, Turin (Italy)
 Publication Date:
 OSTI Identifier:
 21020407
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevD.75.084038; (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; COSMOLOGY; COUPLING; DENSITY; EMISSION; EXCITATION; GAUGE INVARIANCE; GRAVITATIONAL WAVES; NONLINEAR PROBLEMS; OSCILLATION MODES; OSCILLATIONS; RELATIVISTIC RANGE; STARS; VARIATIONS
Citation Formats
Passamonti, Andrea, Stergioulas, Nikolaos, and Nagar, Alessandro. Gravitational waves from nonlinear couplings of radial and polar nonradial modes in relativistic stars. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.084038.
Passamonti, Andrea, Stergioulas, Nikolaos, & Nagar, Alessandro. Gravitational waves from nonlinear couplings of radial and polar nonradial modes in relativistic stars. United States. doi:10.1103/PHYSREVD.75.084038.
Passamonti, Andrea, Stergioulas, Nikolaos, and Nagar, Alessandro. Sun .
"Gravitational waves from nonlinear couplings of radial and polar nonradial modes in relativistic stars". United States.
doi:10.1103/PHYSREVD.75.084038.
@article{osti_21020407,
title = {Gravitational waves from nonlinear couplings of radial and polar nonradial modes in relativistic stars},
author = {Passamonti, Andrea and Stergioulas, Nikolaos and Nagar, Alessandro},
abstractNote = {The postbounce oscillations of newlyborn relativistic stars are expected to lead to gravitationalwave emission through the excitation of nonradial oscillation modes. At the same time, the star is oscillating in its radial modes, with a central density variation that can reach several percent. Nonlinear couplings between radial oscillations and polar nonradial modes lead to the appearance of combination frequencies (sums and differences of the linear mode frequencies). We study such combination frequencies using a gaugeinvariant perturbative formalism, which includes bilinear coupling terms between different oscillation modes. For typical values of the energy stored in each mode we find that gravitational waves emitted at combination frequencies could become detectable in galactic corecollapse supernovae with advanced interferometric or wideband resonant detectors.},
doi = {10.1103/PHYSREVD.75.084038},
journal = {Physical Review. D, Particles Fields},
number = 8,
volume = 75,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}

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