Impact of eccentricity and mean anomaly in numerical relativity mergers

Accurate modelling of black hole binaries is critical to achieve the sciencegoals of gravitational-wave detectors. Modelling such configurations reliesstrongly on calibration to numerical-relativity (NR) simulations. Binaries onquasi-circular orbits have been widely explored in NR, however, coverage of thebroader 9-dimensional parameter space, including orbital eccentricity, remainssparse. This article develops a new procedure to control orbital eccentricityof binary black hole simulations that enables choosing initial data parameterswith precise control over eccentricity and mean anomaly of the subsequentevolution, as well as the coalescence time. We then calculate several sequencesof NR simulations that nearly uniformly cover the 2-dimensionaleccentricity--mean anomaly space for equal mass, non-spinning binary blackholes. We demonstrate that, for fixed eccentricity, many quantities related tothe merger dynamics of binary black holes show an oscillatory dependence onmean anomaly. The amplitude of these oscillations scales nearly linearly withthe eccentricity of the system. We find that for the eccentricities explored inthis work, deviations in various quantities such as the merger amplitude andpeak luminosity can approach $\sim5\%$ of their quasi-circular value. We useour findings to explain eccentric phenomena reported in other studies. We alsoshow that methods for estimating the remnant mass employed in theeffective-one-body approach exhibit similar deviations, roughly matching theamplitude of the oscillations we find in NR simulations. This work is animportant step towards a complete description of eccentric binary black holemergers, and demonstrates the importance of considering the entire2-dimensional parameter subspace related to eccentricity.<br

Accurate waveforms for eccentric, aligned-spin binary black holes: The multipolar effective-one-body model SEOBNRv5EHM

The measurement of orbital eccentricity in gravitational-wave (GW) signalswill provide unique insights into the astrophysical origin of binary systems,while ignoring eccentricity in waveform models could introduce significantbiases in parameter estimation and tests of General Relativity. UpcomingLIGO-Virgo-KAGRA observing runs are expected to detect a subpopulation ofeccentric signals, making it vital to develop accurate waveform models foreccentric orbits. Here, employing recent analytical results through the thirdpost-Newtonian order, we develop SEOBNRv5EHM: a new time-domain,effective-one-body, multipolar waveform model for eccentric binary black holeswith spins aligned (or antialigned) with the orbital angular momentum. Besidesthe dominant (2,2) mode, the model includes the (2,1), (3,3), (3,2), (4,4) and(4,3) modes. We validate the model's accuracy by computing its unfaithfulnessagainst 99 (28 public and 71 private) eccentric numerical-relativity (NR)simulations, produced by the Simulating eXtreme Spacetimes Collaboration.Importantly, for NR waveforms with initial GW eccentricities below 0.5, themaximum (2,2)-mode unfaithfulness across the total mass range 20-200 $M_\odot$is consistently below or close to $1 \%$, with a median value of $\sim 0.02 \%$, reflecting an accuracy improvement of approximately an order of magnitudecompared to the previous-generation SEOBNRv4EHM and the state-of-the-artTEOBResumS-Dal\'i eccentric model. In the quasi-circular-orbit limit,SEOBNRv5EHM is in excellent agreement with the highly accurate SEOBNRv5HMmodel. The accuracy, robustness, and speed of SEOBNRv5EHM make it suitable fordata analysis and astrophysical studies. We demonstrate this by performing aset of recovery studies of synthetic NR-signal injections, andparameter-estimation analyses of the events GW150914 and GW190521, which wefind to have no eccentricity signatures.<br

Open Data from LIGO, Virgo, and KAGRA through the First Part of the Fourth Observing Run

The Gravitational-Wave Transient Catalog (GWTC) is a collection of short-duration (transient) gravitational wave signals identified by the LIGO-Virgo-KAGRA Collaboration in gravitational-wave data produced by the eponymous detectors. The catalog provides information about the identified candidates, such as the arrival time and amplitude of the signal and properties of the signal's source as inferred from the observational data. GWTC is the data release of this dataset and version 4.0 extends the catalog to include observations made during the first part of the fourth LIGO-Virgo-KAGRA observing run up until 2024 January 31. This paper marks an introduction to a collection of articles related to this version of the catalog, GWTC-4.0. The collection of articles accompanying the catalog provides documentation of the methods used to analyze the data, summaries of the catalog of events, observational measurements drawn from the population, and detailed discussions of selected candidate

Directed searches for gravitational waves from ultralight vector boson clouds around merger remnant and galactic black holes during the first part of the fourth LIGO-Virgo-KAGRA observing run

The Gravitational-Wave Transient Catalog (GWTC) is a collection of short-duration (transient) gravitational wave signals identified by the LIGO-Virgo-KAGRA Collaboration in gravitational-wave data produced by the eponymous detectors. The catalog provides information about the identified candidates, such as the arrival time and amplitude of the signal and properties of the signal's source as inferred from the observational data. GWTC is the data release of this dataset and version 4.0 extends the catalog to include observations made during the first part of the fourth LIGO-Virgo-KAGRA observing run up until 2024 January 31. This paper marks an introduction to a collection of articles related to this version of the catalog, GWTC-4.0. The collection of articles accompanying the catalog provides documentation of the methods used to analyze the data, summaries of the catalog of events, observational measurements drawn from the population, and detailed discussions of selected candidate

Upper Limits on the Isotropic Gravitational-Wave Background from the first part of LIGO, Virgo, and KAGRA's fourth Observing Run

The Gravitational-Wave Transient Catalog (GWTC) is a collection of short-duration (transient) gravitational wave signals identified by the LIGO-Virgo-KAGRA Collaboration in gravitational-wave data produced by the eponymous detectors. The catalog provides information about the identified candidates, such as the arrival time and amplitude of the signal and properties of the signal's source as inferred from the observational data. GWTC is the data release of this dataset and version 4.0 extends the catalog to include observations made during the first part of the fourth LIGO-Virgo-KAGRA observing run up until 2024 January 31. This paper marks an introduction to a collection of articles related to this version of the catalog, GWTC-4.0. The collection of articles accompanying the catalog provides documentation of the methods used to analyze the data, summaries of the catalog of events, observational measurements drawn from the population, and detailed discussions of selected candidate

GW231123: a Binary Black Hole Merger with Total Mass 190-265 M⊙

The Gravitational-Wave Transient Catalog (GWTC) is a collection of short-duration (transient) gravitational wave signals identified by the LIGO-Virgo-KAGRA Collaboration in gravitational-wave data produced by the eponymous detectors. The catalog provides information about the identified candidates, such as the arrival time and amplitude of the signal and properties of the signal's source as inferred from the observational data. GWTC is the data release of this dataset and version 4.0 extends the catalog to include observations made during the first part of the fourth LIGO-Virgo-KAGRA observing run up until 2024 January 31. This paper marks an introduction to a collection of articles related to this version of the catalog, GWTC-4.0. The collection of articles accompanying the catalog provides documentation of the methods used to analyze the data, summaries of the catalog of events, observational measurements drawn from the population, and detailed discussions of selected candidate

Black Hole Spectroscopy and Tests of General Relativity with GW250114

The Gravitational-Wave Transient Catalog (GWTC) is a collection of short-duration (transient) gravitational wave signals identified by the LIGO-Virgo-KAGRA Collaboration in gravitational-wave data produced by the eponymous detectors. The catalog provides information about the identified candidates, such as the arrival time and amplitude of the signal and properties of the signal's source as inferred from the observational data. GWTC is the data release of this dataset and version 4.0 extends the catalog to include observations made during the first part of the fourth LIGO-Virgo-KAGRA observing run up until 2024 January 31. This paper marks an introduction to a collection of articles related to this version of the catalog, GWTC-4.0. The collection of articles accompanying the catalog provides documentation of the methods used to analyze the data, summaries of the catalog of events, observational measurements drawn from the population, and detailed discussions of selected candidate

GWTC-4.0: An Introduction to Version 4.0 of the Gravitational-Wave Transient Catalog

The Gravitational-Wave Transient Catalog (GWTC) is a collection of short-duration (transient) gravitational wave signals identified by the LIGO-Virgo-KAGRA Collaboration in gravitational-wave data produced by the eponymous detectors. The catalog provides information about the identified candidates, such as the arrival time and amplitude of the signal and properties of the signal's source as inferred from the observational data. GWTC is the data release of this dataset and version 4.0 extends the catalog to include observations made during the first part of the fourth LIGO-Virgo-KAGRA observing run up until 2024 January 31. This paper marks an introduction to a collection of articles related to this version of the catalog, GWTC-4.0. The collection of articles accompanying the catalog provides documentation of the methods used to analyze the data, summaries of the catalog of events, observational measurements drawn from the population, and detailed discussions of selected candidate

GWTC-4.0: Updating the Gravitational-Wave Transient Catalog with Observations from the First Part of the Fourth LIGO-Virgo-KAGRA Observing Run

The Gravitational-Wave Transient Catalog (GWTC) is a collection of short-duration (transient) gravitational wave signals identified by the LIGO-Virgo-KAGRA Collaboration in gravitational-wave data produced by the eponymous detectors. The catalog provides information about the identified candidates, such as the arrival time and amplitude of the signal and properties of the signal's source as inferred from the observational data. GWTC is the data release of this dataset and version 4.0 extends the catalog to include observations made during the first part of the fourth LIGO-Virgo-KAGRA observing run up until 2024 January 31. This paper marks an introduction to a collection of articles related to this version of the catalog, GWTC-4.0. The collection of articles accompanying the catalog provides documentation of the methods used to analyze the data, summaries of the catalog of events, observational measurements drawn from the population, and detailed discussions of selected candidate

GWTC-4.0: Population Properties of Merging Compact Binaries

The Gravitational-Wave Transient Catalog (GWTC) is a collection of short-duration (transient) gravitational wave signals identified by the LIGO-Virgo-KAGRA Collaboration in gravitational-wave data produced by the eponymous detectors. The catalog provides information about the identified candidates, such as the arrival time and amplitude of the signal and properties of the signal's source as inferred from the observational data. GWTC is the data release of this dataset and version 4.0 extends the catalog to include observations made during the first part of the fourth LIGO-Virgo-KAGRA observing run up until 2024 January 31. This paper marks an introduction to a collection of articles related to this version of the catalog, GWTC-4.0. The collection of articles accompanying the catalog provides documentation of the methods used to analyze the data, summaries of the catalog of events, observational measurements drawn from the population, and detailed discussions of selected candidate