Relativistic simulations of eccentric binary neutron star mergers: One-arm spiral instability and effects of neutron star spin

East, William E.; Paschalidis, Vasileios; Pretorius, Frans; Shapiro, Stuart L.

doi:10.1103/physrevd.93.024011

Cited by 132 publications

(180 citation statements)

References 113 publications

(156 reference statements)

Supporting

Mentioning

166

Contrasting

Order By: Relevance

“…V of Paper I, and focuses on the dominant (2, 2) mode of the GW strain. We often useω := M ω 22 (28) for the dimensionless and mass-rescaled GW frequency. GWs are plotted versus the retarded time u.…”

Section: Gravitational Wavesmentioning

confidence: 99%

“…I of [24] for a discussion). Alternative NR evolutions of spinning BNS were presented in [25][26][27] employing constraint violating initial data, and in [28][29][30] employing constraint satisfying data which however do not fulfill-ing the equations for hydrodynamical equilibrium. Spinning BNS were also considered with a smooth particle hydrodynamics code under the assumption of conformal flatness, e.g.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Gravitational waves and mass ejecta from binary neutron star mergers: Effect of the stars’ rotation

et al. 2017

View full text Add to dashboard Cite

We present new (3+1) dimensional numerical relativity simulations of the binary neutron star (BNS) mergers that take into account the NS spins. We consider different spin configurations, aligned or antialigned to the orbital angular momentum, for equal and unequal mass BNS and for two equations of state. All the simulations employ quasiequilibrium circular initial data in the constant rotational velocity approach, i.e. they are consistent with Einstein equations and in hydrodynamical equilibrium. We study the NS rotation effect on the energetics, the gravitational waves (GWs) and on the possible electromagnetic (EM) emission associated to dynamical mass ejecta. For dimensionless spin magnitudes of χ ∼ 0.1 we find that both spin-orbit interactions and spin-induced-quadrupole deformations affect the late-inspiral-merger dynamics. The latter is, however, dominated by finite-size effects. Spin (tidal) effects contribute to GW phase differences up to ∼ 5 (20) radians accumulated during the last eight orbits to merger. Similarly, after merger the collapse time of the remnant and the GW spectrogram are affected by the NSs rotation. Spin effects in dynamical ejecta are clearly observed in unequal mass systems in which mass ejection originates from the tidal tail of the companion. Consequently kilonovae and other EM counterparts are affected by spins. We find that spin aligned to the orbital angular momentum leads to brighter EM counterparts than antialigned spin with luminosities up to a factor of two higher.

show abstract

Section: Gravitational Wavesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Gravitational waves and mass ejecta from binary neutron star mergers: Effect of the stars’ rotation

et al. 2017

View full text Add to dashboard Cite

show abstract

“…Furthermore, this method could be adapted to constrain or search for other smallamplitude features that might be shared by a population of events, e.g. common parameterized post-Einsteinianlike [43] corrections to the inspiral phase of the mergers, or common equation-of-state-discriminating frequencies excited in hypermassive remnants of binary neutron star mergers [44][45][46][47][48][49][50][51][52][53][54]. In this latter example, one issue in adapting the coherent stacking method would be achieving phase alignment, due to the challenge in accurately calculating the details of the matter dynamics post-merger.…”

Section: Hypothesis Testingmentioning

confidence: 99%

Black Hole Spectroscopy with Coherent Mode Stacking

et al. 2017

Self Cite

View full text Add to dashboard Cite

The measurement of multiple ringdown modes in gravitational waves from binary black hole mergers will allow for testing fundamental properties of black holes in General Relativity, and to constrain modified theories of gravity. To enhance the ability of Advanced LIGO/Virgo to perform such tasks, we propose a coherent mode stacking method to search for a chosen target mode within a collection of multiple merger events. We first rescale each signal so that the target mode in each of them has the same frequency, and then sum the waveforms constructively. A crucial element to realize this coherent superposition is to make use of a priori information extracted from the inspiral-merger phase of each event. To illustrate the method, we perform a study with simulated events targeting the = m = 3 ringdown mode of the remnant black holes. We show that this method can significantly boost the signal-to-noise ratio of the collective target mode compared to that of the single loudest event. Using current estimates of merger rates we show that it is likely that advanced-era detectors can measure this collective ringdown mode with one year of coincident data gathered at design sensitivity.Introduction. The recent detection of gravitational waves (GWs) emitted during the coalescence of binary black holes [1, 2] marked the beginning of the era of gravitational wave astronomy, a feat that heralds a boom of scientific discoveries to come. GWs not only provide a new window to our universe, they also offer a unique opportunity to test General Relativity (GR) in the dynamical and highly non-linear gravitational regime [3][4][5][6][7]. One celebrated prediction of GR is the uniqueness, or "no-hair" property of vacuum black holes (BHs) [8][9][10][11][12]: all isolated BHs are described by the Kerr family of solutions, each uniquely characterized by only its mass and spin [69]. This property has many wide-ranging consequences, the two most relevant here being (a) that the spacetime of an isolated binary black hole (BBH) inspiral is uniquely characterized by a small, finite set of parameters identifying the two BHs in the binary and the properties of the orbit, and (b) that this same set of parameters uniquely determines the merger remnant and the full spectrum of its quasinormal mode (QNM) ringdown waveform.This latter point forms the basis of black hole spectroscopy, where measurements of multiple ringdown modes are used to test this no-hair property. The idea is as follows. If the no-hair property holds, a measurement of the (complex) frequency of one QNM can be inverted to find a discrete set of possibilities for the spherical harmonic ( , m) plus overtone number n of the mode, and the BH mass M and spin parameter a = | S|/M 2 , where S is the BH spin angular momentum. However, if we have a priori information about the objects that merged to form the perturbed BH, then we also have information

show abstract

“…For instance, one could apply this to the 21 mode, which can become strong if a one-arm instability develops in the BNS remnant [24][25][26][27]. In this case, there is a tight correlation between the frequencies of the 21 and 22 modes which can be exploited to further enhance the achievable stacked SNR.…”

Section: Discussionmentioning

confidence: 99%

“…In the first 10-20 ms after merger, the dominant component of a postmerger GW is the l ¼ m ¼ 2 mode (which we call here the 22 mode for short). For BNS merger remnants that may survive for longer times, a one-arm mode (l ¼ 2, m ¼ 1, or 21 mode) can dominate the GWemission [24][25][26][27][28].…”

Section: Introductionmentioning

confidence: 99%

Gravitational wave spectroscopy of binary neutron star merger remnants with mode stacking

et al. 2018

Self Cite

View full text Add to dashboard Cite

A binary neutron star coalescence event has recently been observed for the first time in gravitational waves, and many more detections are expected once current ground-based detectors begin operating at design sensitivity. As in the case of binary black holes, gravitational waves generated by binary neutron stars consist of inspiral, merger, and postmerger components. Detecting the latter is important because it encodes information about the nuclear equation of state in a regime that cannot be probed prior to merger. The postmerger signal, however, can only be expected to be measurable by current detectors for events closer than roughly ten megaparsecs, which given merger rate estimates implies a low probability of observation within the expected lifetime of these detectors. We carry out Monte Carlo simulations showing that the dominant postmerger signal (the l ¼ m ¼ 2 mode) from individual binary neutron star mergers may not have a good chance of observation even with the most sensitive future ground-based gravitational wave detectors proposed so far (the Einstein Telescope and Cosmic Explorer, for certain equations of state, assuming a full year of operation, the latest merger rates, and a detection threshold corresponding to a signal-to-noise ratio of 5). For this reason, we propose two methods that stack the postmerger signal from multiple binary neutron star observations to boost the postmerger detection probability. The first method follows a commonly used practice of multiplying the Bayes factors of individual events. The second method relies on an assumption that the mode phase can be determined from the inspiral waveform, so that coherent mode stacking of the data from different events becomes possible. We find that both methods significantly improve the chances of detecting the dominant postmerger signal, making a detection very likely after a year of observation with Cosmic Explorer for certain equations of state. We also show that in terms of detection, coherent stacking is more efficient in accumulating confidence for the presence of postmerger oscillations in a signal than the first method. Moreover, assuming the postmerger signal is detected with Cosmic Explorer via stacking, we estimate through a Fisher analysis that the peak frequency can be measured to a statistical error of ∼4-20 Hz for certain equations of state. Such an error corresponds to a neutron star radius measurement to within ∼15-56 m, a fractional relative error ∼4%, suggesting that systematic errors from theoretical modeling ð≳100 m) may dominate the error budget.

show abstract

Relativistic simulations of eccentric binary neutron star mergers: One-arm spiral instability and effects of neutron star spin

Cited by 132 publications

References 113 publications

Gravitational waves and mass ejecta from binary neutron star mergers: Effect of the stars’ rotation

Gravitational waves and mass ejecta from binary neutron star mergers: Effect of the stars’ rotation

Black Hole Spectroscopy with Coherent Mode Stacking

Gravitational wave spectroscopy of binary neutron star merger remnants with mode stacking

Contact Info

Product

Resources

About