27 research outputs found
Theoretical groundwork supporting the precessing-spin two-body dynamics of the effective-one-body waveform models SEOBNRv5
Waveform models are essential for gravitational-wave (GW) detection and
parameter estimation of coalescing compact-object binaries. More accurate
models are required for the increasing sensitivity of current and future GW
detectors. The effective-one-body (EOB) formalism combines the post-Newtonian
(PN) and small mass-ratio approximations with numerical-relativity results, and
produces highly accurate inspiral-merger-ringdown waveforms. In this paper, we
derive the analytical precessing-spin two-body dynamics for the
\texttt{SEOBNRv5} waveform model, which has been developed for the upcoming
LIGO-Virgo-KAGRA observing run. We obtain an EOB Hamiltonian that reduces to
the exact Kerr Hamiltonian in the test-mass limit. It includes the full 4PN
precessing-spin information, and is valid for generic compact objects (i.e.,
for black holes or neutron stars). We also build an efficient and accurate EOB
Hamiltonian that includes partial precessional effects, notably orbit-averaged
in-plane spin effects for circular orbits, and derive 4PN-expanded
precessing-spin equations of motion, consistent with such an EOB Hamiltonian.
The results were used to build the computationally-efficient precessing-spin
multipolar \texttt{SEOBNRv5PHM} waveform model.Comment: 35 page
SEOBNRv5PHM: Next generation of accurate and efficient multipolar precessing-spin effective-one-body waveforms for binary black holes
Spin precession is one of the key physical effects that could unveil the
origin of the compact binaries detected by ground- and space-based
gravitational-wave (GW) detectors, and shed light on their possible formation
channels. Efficiently and accurately modeling the GW signals emitted by these
systems is crucial to extract their properties. Here, we present SEOBNRv5PHM, a
multipolar precessing-spin waveform model within the effective-one-body (EOB)
formalism for the full signal (i.e. inspiral, merger and ringdown) of binary
black holes (BBHs). In the non-precessing limit, the model reduces to
SEOBNRv5HM, which is calibrated to numerical-relativity (NR) simulations,
13 waveforms from BH perturbation theory, and non-spinning energy flux from
second-order gravitational self-force theory. We remark that SEOBNRv5PHM is not
calibrated to precessing-spin NR waveforms from the Simulating eXtreme
Spacetimes Collaboration. We validate SEOBNRv5PHM by computing the
unfaithfulness against 1543 precessing-spin NR waveforms, and find that for
99.8% (84.4%) of the cases, the maximum value, in the total mass range 20-300
, is below 3% (1%). These numbers reduce to 95.3% (60.8%) when using
the previous version of the SEOBNR family, SEOBNRv4PHM, and to 78.2% (38.3%)
when using the state-of-the-art frequency-domain multipolar precessing-spin
phenomenological IMRPhenomXPHM model. Due to much better computational
efficiency of SEOBNRv5PHM compared to SEOBNRv4PHM, we are also able to perform
extensive Bayesian parameter estimation on synthetic signals and GW events
observed by LIGO-Virgo detectors. We show that SEOBNRv5PHM can be used as a
standard tool for inference analyses to extract astrophysical and cosmological
information of large catalogues of BBHs
IMRPhenomXHM: A multi-mode frequency-domain model for the gravitational wave signal from non-precessing black-hole binaries
We present the IMRPhenomXHM frequency domain phenomenological waveform model
for the inspiral, merger and ringdown of quasi-circular non-precessing black
hole binaries. The model extends the IMRPhenomXAS waveform model, which
describes the dominant quadrupole modes , to the harmonics
, and includes mode mixing effects for
the spherical harmonic. IMRPhenomXHM is calibrated against hybrid
waveforms, which match an inspiral phase described by the effective-one-body
model and post-Newtonian amplitudes for the subdominant harmonics to numerical
relativity waveforms and numerical solutions to the perturbative Teukolsky
equation for large mass ratios up to 1000.
A computationally efficient implementation of the model is available as part
of the LSC Algorithm Library Suite.Comment: 30 pages, 23 figures. Updated to match published versio
Constraints from LIGO O3 Data on Gravitational-wave Emission Due to R-modes in the Glitching Pulsar PSR J0537-6910
Abbott, R., et al.We present a search for continuous gravitational-wave emission due to r-modes in the pulsar PSR J0537-6910 using data from the LIGO-Virgo Collaboration observing run O3. PSR J0537-6910 is a young energetic X-ray pulsar and is the most frequent glitcher known. The inter-glitch braking index of the pulsar suggests that gravitational-wave emission due to r-mode oscillations may play an important role in the spin evolution of this pulsar. Theoretical models confirm this possibility and predict emission at a level that can be probed by ground-based detectors. In order to explore this scenario, we search for r-mode emission in the epochs between glitches by using a contemporaneous timing ephemeris obtained from NICER data. We do not detect any signals in the theoretically expected band of 86-97 Hz, and report upper limits on the amplitude of the gravitational waves. Our results improve on previous amplitude upper limits from r-modes in J0537-6910 by a factor of up to 3 and place stringent constraints on theoretical models for r-mode-driven spin-down in PSR J0537-6910, especially for higher frequencies at which our results reach below the spin-down limit defined by energy conservation.This work was supported by MEXT, JSPS Leading-edge Research Infrastructure Program, JSPS Grant-in-Aid for Specially Promoted Research 26000005, JSPS Grant-in-Aid for Scientific Research on Innovative Areas 2905: JP17H06358, JP17H06361 and JP17H06364, JSPS Core-to-Core Program A. Advanced Research Networks, JSPS Grant-in-Aid for Scientific Research (S) 17H06133, the joint research program of the Institute for Cosmic Ray Research, University of Tokyo, National Research Foundation (NRF) and Computing Infrastructure Project of KISTI-GSDC in Korea, Academia Sinica (AS), AS Grid Center (ASGC) and the Ministry of Science and Technology (MoST) in Taiwan under grants including AS-CDA-105-M06, Advanced Technology Center (ATC) of NAOJ, and Mechanical Engineering Center of KEK. We would like to thank all of the essential workers who put their health at risk during the COVID-19 pandemic, without whom we would not have been able to complete this work
All-sky search for continuous gravitational waves from isolated neutron stars in the early O3 LIGO data
Abbott, R. (LIGO Scientific Collaboration, Virgo Collaboration, KAGRA Collaboration)We report on an all-sky search for continuous gravitational waves in the frequency band 20-2000 Hz and with a frequency time derivative in the range of [-1.0,+0.1]×10-8 Hz/s. Such a signal could be produced by a nearby, spinning and slightly nonaxisymmetric isolated neutron star in our Galaxy. This search uses the LIGO data from the first six months of Advanced LIGO's and Advanced Virgo's third observational run, O3. No periodic gravitational wave signals are observed, and 95% confidence-level (C.L.) frequentist upper limits are placed on their strengths. The lowest upper limits on worst-case (linearly polarized) strain amplitude h0 are ∼1.7×10-25 near 200 Hz. For a circularly polarized source (most favorable orientation), the lowest upper limits are ∼6.3×10-26. These strict frequentist upper limits refer to all sky locations and the entire range of frequency derivative values. For a population-averaged ensemble of sky locations and stellar orientations, the lowest 95% C.L. upper limits on the strain amplitude are ∼1.4×10-25. These upper limits improve upon our previously published all-sky results, with the greatest improvement (factor of ∼2) seen at higher frequencies, in part because quantum squeezing has dramatically improved the detector noise level relative to the second observational run, O2. These limits are the most constraining to date over most of the parameter space searched.This work was supported by MEXT, JSPS
Leading-edge Research Infrastructure Program, JSPS
Grant-in-Aid for Specially Promoted Research 26000005,
JSPS Grant-in-Aid for Scientific Research on Innovative
Areas 2905: JP17H06358, JP17H06361 and JP17H06364,
JSPS Core-to-Core Program A. Advanced Research
Networks, JSPS Grant-in-Aid for Scientific Research (S)
17H06133, the joint research program of the Institute for
Cosmic Ray Research, University of Tokyo, National
Research Foundation (NRF) and Computing Infrastructure
Project of KISTI-GSDC in Korea, Academia Sinica (AS),
AS Grid Center (ASGC) and the Ministry of Science and
Technology (MoST) in Taiwan under grants including ASCDA-105-M06, Advanced Technology Center (ATC) of
NAOJ, and Mechanical Engineering Center of KE
Laying the foundation of the effective-one-body waveform models SEOBNRv5: improved accuracy and efficiency for spinning non-precessing binary black holes
We present SEOBNRv5HM, a more accurate and faster inspiral-merger-ringdown
gravitational waveform model for quasi-circular, spinning, nonprecessing binary
black holes within the effective-one-body (EOB) formalism. Compared to its
predecessor, SEOBNRv4HM, the waveform model i) incorporates recent high-order
post- Newtonian results in the inspiral, with improved resummations, ii)
includes the gravitational modes (l, |m|) = (3, 2), (4, 3), in addition to the
(2, 2), (3, 3), (2, 1), (4, 4), (5, 5) modes already implemented in SEOBNRv4HM,
iii) is calibrated to larger mass-ratios and spins using a catalog of 442
numerical-relativity (NR) simulations and 13 additional waveforms from
black-hole perturbation theory, iv) incorporates information from second-order
gravitational self-force (2GSF) in the nonspinning modes and radiation-reaction
force. Computing the unfaithfulness against NR simulations, we find that for
the dominant (2, 2) mode the maximum unfaithfulness in the total mass range
is below for 90% of the cases (38% for
SEOBNRv4HM). When including all modes up to l = 5 we find 98% (49%) of the
cases with unfaithfulness below , while these numbers reduce
to 88% (5%) when using SEOBNRv4HM. Furthermore, the model shows improved
agreement with NR in other dynamical quantities (e.g., the angular momentum
flux and binding energy), providing a powerful check of its physical
robustness. We implemented the waveform model in a high-performance Python
package (pySEOBNR), which leads to evaluation times faster than SEOBNRv4HM by a
factor 10 to 50, depending on the configuration, and provides the flexibility
to easily include spin-precession and eccentric effects, thus making it the
starting point for a new generation of EOBNR waveform models (SEOBNRv5) to be
employed for upcoming observing runs of the LIGO-Virgo-KAGRA detectors