Gravitational Wave Extraction in Simulations of Rotating Stellar Core Collapse
arXiv:1012.0595 · doi:10.1103/PhysRevD.83.064008
Abstract
We perform simulations of general relativistic rotating stellar core collapse and compute the gravitational waves (GWs) emitted in the core bounce phase of three representative models via multiple techniques. The simplest technique, the quadrupole formula (QF), estimates the GW content in the spacetime from the mass quadrupole tensor. It is strictly valid only in the weak-field and slow-motion approximation. For the first time, we apply GW extraction methods in core collapse that are fully curvature-based and valid for strongly radiating and highly relativistic sources. We employ three extraction methods computing (i) the Newman-Penrose (NP) scalar Psi_4, (ii) Regge-Wheeler-Zerilli-Moncrief (RWZM) master functions, and (iii) Cauchy-Characteristic Extraction (CCE) allowing for the extraction of GWs at future null infinity, where the spacetime is asymptotically flat and the GW content is unambiguously defined. The latter technique is the only one not suffering from residual gauge and finite-radius effects. All curvature-based methods suffer from strong non-linear drifts. We employ the fixed-frequency integration technique as a high-pass waveform filter. Using the CCE results as a benchmark, we find that finite-radius NP extraction yields results that agree nearly perfectly in phase, but differ in amplitude by ~1-7% at core bounce, depending on the model. RWZM waveforms, while in general agreeing in phase, contain spurious high-frequency noise of comparable amplitudes to those of the relatively weak GWs emitted in core collapse. We also find remarkably good agreement of the waveforms obtained from the QF with those obtained from CCE. They agree very well in phase but systematically underpredict peak amplitudes by ~5-11% which is comparable to the NP results and is within the uncertainties associated with core collapse physics. (abridged)
26 pages, 10 figures, 5 tables, matches published version
References in corpus (18)
- LIGO: The Laser Interferometer Gravitational-Wave Observatory
- Inspiral, merger and ringdown of unequal mass black hole binaries: a multipolar analysis
- Delayed neutrino-driven supernova explosions aided by the standing accretion-shock instability
- Calibration of Moving Puncture Simulations
- The gravitational wave burst signal from core collapse of rotating stars
- Relativistic neutron star merger simulations with non-zero temperature equations of state I. Variation of binary parameters and equation of state
- Binary black-hole evolutions of excision and puncture data
- 3D Collapse of Rotating Stellar Iron Cores in General Relativity including Deleptonization and a Nuclear Equation of State
- Magnetorotational collapse of massive stellar cores to neutron stars: Simulations in full general relativity
- Generic Gravitational Wave Signals from the Collapse of Rotating Stellar Cores
- A New Mechanism for Gravitational Wave Emission in Core-Collapse Supernovae
- Axisymmetric simulations of magnetorotational core collapse: Approximate inclusion of general relativistic effects
- Gravitational waves from 3D MHD core collapse simulations
- Rotating Collapse of Stellar Iron Cores in General Relativity
- Dealing with delicate issues in waveforms calculations
- Strategies for the Characteristic Extraction of Gravitational Waveforms
- Gravitational-Wave Extraction from Neutron Star Oscillations: comparing linear and nonlinear techniques
- How far away is far enough for extracting numerical waveforms, and how much do they depend on the extraction method?