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In this work we present IMRPhenomTP, a time domain phenomenological model for the dominant l=2, m=|2| modes of coalescing black hole binary systems and its extension to describe general precessing systems within the "twisting up" approximation. The underlying nonprecessing model, IMRPhenomT, is calibrated to the new release of numerical relativity simulations of the SXS Collaboration and its accuracy is comparable to the state-of-the-art nonprecessing dominant mode models as IMRPhenomX and SEOBNRv4. The precessing extension allows for flexibility choosing the Euler angles of the time-dependent rotation between the coprecessing and the inertial reference systems, including the single spin next-to-next-to-leading order and the double spin multiscale analysis post-Newtonian descriptions present in other models, numerical integration of the orbit averaged spin evolution equations, different choices for the evolution of the orbital angular momentum norm, and a simple approximation to the ringdown behavior. [ABSTRACT FROM AUTHOR]

The possible formation of stellar-mass binary black holes through dynamical interactions in dense stellar environments predicts the existence of binaries with non-negligible eccentricity in the frequency band of ground-based gravitational-wave detectors; the detection of binary black hole mergers with measurable orbital eccentricity would validate the existence of this formation channel. Waveform templates currently used in the matched-filter gravitational-wave searches of LIGO-Virgo data neglect effects of eccentricity which is expected to reduce their efficiency to detect eccentric binary black holes. Meanwhile, the sensitivity of coherent unmodeled gravitational-wave searches (with minimal assumptions about the signal model) has been shown to be largely unaffected by the presence of even sizable orbital eccentricity. In this paper, we compare the performance of two state-of-the-art search algorithms recently used by LIGO and Virgo to search for binary black holes in the second observing run (O2), quantifying their search sensitivity by injecting numerical relativity simulations of inspiral-merger-ringdown eccentric waveforms into O2 LIGO data. Our results show that the matched-filter search pycbc performs better than the unmodeled search coherent WaveBurst for the high chirp mass (>20 M⊙) and low eccentricity region (e30 Hz<0.3) of parameter space. For moderate eccentricities and low chirp mass, on the other hand, the unmodeled search is more sensitive than the modeled search. [ABSTRACT FROM AUTHOR]

The current paradigm for constructing waveforms from precessing compact binaries is to first construct a waveform in a noninertial, coprecessing binary source frame followed by a time-dependent rotation to map back to the physical, inertial frame. A key insight in the construction of these models is that the coprecessing waveform can be effectively mapped to some equivalent aligned spin waveform. Secondly, the time-dependent rotation implicitly introduces m-mode mixing, necessitating an accurate description of higher-order modes in the coprecessing frame. We assess the efficacy of this modeling strategy in the strong field regime using numerical relativity simulations. We find that this framework allows for the highly accurate construction of (2,±2) modes in our dataset, while for higher order modes, especially the (2,|1|),(3,|2|) and (4,|3|) modes, we find rather large mismatches. We also investigate a variant of the approximate map between coprecessing and aligned spin waveforms, where we only identify the slowly varying part of the time domain coprecessing waveforms with the aligned-spin one, but find no significant improvement. Our results indicate that the simple paradigm to construct precessing waveforms does not provide an accurate description of higher order modes in the strong-field regime and demonstrate the necessity for modeling mode asymmetries and mode-mixing to significantly improve the description of precessing higher order modes. [ABSTRACT FROM AUTHOR]

We analyze a new numerical relativity dataset of spinning but nonprecessing binary black holes on eccentric orbits, with eccentricities from approximately 0.1 to 0.5, with dimensionless spins up to 0.75 included at mass ratios q=m1/m2=(1,2), and further nonspinning binaries at mass ratios q=(1.5,3,4). A comparison of the final mass and spin of these simulations with noneccentric data extends previous results in the literature on circularization of eccentric binaries to the spinning case. For the (l,m)=(2,2) spin-weighted spherical harmonic mode, we construct eccentric hybrid waveforms that connect the numerical relativity data to a post-Newtonian description for the inspiral, and we discuss the limitations in the current knowledge about post-Newtonian theory which complicate the generation of eccentric hybrid waveforms. We also perform a Bayesian parameter estimation study, quantifying the parameter biases introduced when using three different quasicircular waveform models to estimate the parameters of highly eccentric binary systems. We find that the used aligned-spin quasicircular model including higher order modes produces lower bias in certain parameters than the nonprecessing quasicircular model without higher order modes and the quasicircular precessing model. [ABSTRACT FROM AUTHOR]

We present simple procedures to construct quasicircular initial data for numerical evolutions of binary black hole spacetimes. Our method consists of using the post-Newtonian (PN) theory in three ways: first to provide an initial guess for the initial momenta at 3.5PN order that implies low residual eccentricity, second to measure the resulting eccentricity, and third to calculate corrections to the momenta or initial separation that further reduce the eccentricity. Regarding the initial guess, we compare numerical evolutions in post-Newtonian theory to the postcircular and post-postcircular analytical approximations to quasicircular data. We discuss a robust fitting procedure to measure eccentricity from numerical simulations using the orbital frequency Ω, and derive from the quasi-Keplerian parametrization at 1PN order the correction factors for the tangential and radial momentum components required to reduce the measured eccentricity to zero. We first test our procedure integrating PN equations of motion at 3.5PN where low eccentric initial data are easily obtained, and then apply our method to sets of binary black hole numerical relativity simulations with different mass ratios (q=m2/m1=1,2,...,8), spin configurations, and separations. Our set of simulations contains nonspinning, spin-aligned, and precessing simulations. We observe that the iterative procedure produces low eccentric simulations with eccentricities of the order O(10-4) with only one iteration. The simplicity of the procedure allows one to obtain low eccentric numerical relativity simulations easily and save computational resources. Moreover, the analytical PN formulas derived in this paper will be useful to generate eccentric hybrid waveforms. [ABSTRACT FROM AUTHOR]

We present imrphenomxphm, a phenomenological frequency-domain model for the gravitational-wave signal emitted by quasicircular precessing binary black holes, which incorporates multipoles beyond the dominant quadrupole in the precessing frame. The model is a precessing extension of imrphenomxhm, [C. García-Quirós et al., Phys. Rev. D 102, 064002 (2020)] based on approximate maps between aligned-spin waveform modes in the coprecessing frame and precessing waveform modes in the inertial frame, which is commonly referred to as "twisting up" the nonprecessing waveforms. imrphenomxphm includes imrphenomxp as a special case, the restriction to the dominant quadrupole contribution in the coprecessing frame. We implement two alternative mappings, one based on a single-spin post-Newtonian approximation, as used in imrphenompv2 [M. Hannam et al., Phys. Rev. Lett. 113, 151101 (2014).], and one based on the double-spin multiple scale analysis approach of [K. Chatziioannou et al., Phys. Rev. D 95, 104004 (2017).]. We include a detailed discussion of conventions used in the description of precessing binaries and of all choices made in constructing the model. The computational cost of imrphenomxphm is further reduced by extending the interpolation technique of [C. García-Quirós et al., Classical Quant. Grav. 38, 015006 (2021).] to the Euler angles. The accuracy, speed, robustness, and modularity of the imrphenomx family will make these models productive tools for gravitational wave astronomy in the current era of greatly increased number and diversity of detected events. [ABSTRACT FROM AUTHOR]

We reanalyze the gravitational-wave event GW190412 with state-of-the-art phenomenological waveform models. This event, which has been associated with a black hole merger, is interesting due to the significant contribution from subdominant harmonics. We use both frequency-domain and time-domain waveform models. The PhenomX waveform models constitute the fourth generation of frequency-domain phenomenological waveforms for black hole binary coalescence; they have more recently been complemented by the time-domain PhenomT models, which open up new strategies to model precession and eccentricity, and to perform tests of general relativity with the phenomenological waveforms approach. Both PhenomX and PhenomT have been constructed with similar techniques and accuracy goals, and due to their computational efficiency this "generation X" model family allows the routine use of subdominant spherical harmonics in Bayesian inference. We show the good agreement between these and other state-of-the-art waveform models for GW190412, and discuss the improvements over the previous generation of phenomenological waveform models. We also discuss practical aspects of Bayesian inference such as run convergence, variations of sampling parameters, and computational cost. [ABSTRACT FROM AUTHOR]

We present the imrphenomxhm frequency domain phenomenological waveform model for the inspiral, merger, and ringdown of quasicircular nonprecessing black hole binaries. The model extends the imrphenomxas waveform model [G. Pratten, S. Husa, C. García-Quirós, M. Colleoni, A. Ramos-Buades, H. Estellés, and R. Jaume, preceding paper, Phys. Rev. D 102, 064001 (2020)], which describes the dominant quadrupole modes l=|m|=2, to the harmonics (l,|m|)=(2,1),(3,3),(3,2),(4,4), and includes mode mixing effects for the (3,2) 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. [ABSTRACT FROM AUTHOR]

In this paper we present imrphenomxas, a thorough overhaul of the imrphenomd [S. Husa et al., Phys. Rev. D 93, 044006 (2016); S. Khan et al., Phys. Rev. D 93, 044007 (2016)] waveform model, which describes the dominant l=2, |m|=2 spherical harmonic mode of nonprecessing coalescing black holes in terms of piecewise closed form expressions in the frequency domain. Improvements include in particular the accurate treatment of unequal spin effects, and the inclusion of extreme mass ratio waveforms. imrphenomd has previously been extended to approximately include spin precession [M. Hannam et al., Phys. Rev. Lett. 113, 151101 (2014)] and subdominant spherical harmonics [L. London et al., Phys. Rev. Lett. 120, 161102 (2018)], and with its extensions it has become a standard tool in gravitational wave parameter estimation. Improved extensions of imrphenomxas are discussed in companion papers [C. García-Quirós et al., Phys. Rev. D 102, 064002 (2020); G. Pratten et al., arXiv:2004.06503]. [ABSTRACT FROM AUTHOR]