Frequency-domain gravitational waves from nonprecessing black-hole binaries. I. New numerical waveforms and anatomy of the signal

Abstract

In this paper we discuss the anatomy of frequency-domain gravitational-wave signals from non-precessing black-hole coalescences with the goal of constructing accurate phenomenological waveform models. We first present new numerical-relativity simulations for mass ratios up to 18, including spins. From a comparison of different post-Newtonian approximants with numerical-relativity data we select the uncalibrated SEOBNRv2 model as the most appropriate for the purpose of constructing hybrid post-Newtonian/numerical-relativity waveforms, and we discuss how we prepare time-domain and frequency-domain hybrid data sets. We then use our data together with results in the literature to calibrate simple explicit expressions for the final spin and radiated energy. Equipped with our prediction for the final state we then develop a simple and accurate mergerringdown-model based on modified Lorentzians in the gravitational wave amplitude and phase, and we discuss a simple method to represent the low frequency signal augmenting the TaylorF2 post-Newtonian approximant with terms corresponding to higher orders in the post-Newtonian expansion. We finally discuss different options for modelling the small intermediate frequency regime between inspiral and merger-ringdown. A complete phenomenological model based on the present work is presented in a companion paper [1].

Binary Black Hole Mergers in the First Advanced LIGO Observing Run

“…The analysis makes use of two waveform models, the double aligned spin waveform model (EOBNR) [8,9] and an effective precessing spin model (IMRPhenom) [36][37][38]. Results from the two waveforms are similar, and the data give us little reason to prefer one model over the other.…”

“…[41], to analyze GW151226, we start from the IMRPhenom waveform model of Refs. [36][37][38], which is capable of describing inspiral, merger, and ringdown, and partly accounts for spin precession. The phase of this waveform is characterized by coefficients fp i g, which include PN coefficients, as well as phenomenological coefficients describing merger and ringdown.…”

“…We estimate the masses of these using fitting formulas calibrated to numerical relativity simulations [36,101]. Each final mass is 0.95-0.98 of the initial total mass of the binary components, as similar fractions of 0.02-0.05 are radiated away as gravitational waves.…”

“…We provide a detailed evaluation of the source properties and inferred parameters of GW150914, GW151226, and LVT151012. We use models of the waveform covering the inspiral, merger, and ringdown phases based on combining post-Newtonian (PN) theory [19][20][21][22][23][24], the effective-onebody (EOB) formalism [25][26][27][28][29], and numerical relativity simulations [30][31][32][33][34][35][36]. One model is restricted to spins aligned with the orbital angular momentum [8,9], while the other allows for nonaligned orientation of the spins, which can lead to precession of the orbital plane [37,38].…”

Optimizing spinning time-domain gravitational waveforms for advanced LIGO data analysis

“…As an example, consider the "Phenom" family of phenomenological gravitational waveform models [7][8][9][10]. Recent "Phenom" models use the state-of-the-art, purely perturbative SEOBv2 (Spinning Effective One-Body, version 2) model for the inspiral part of the waveform (i.e., an uncalibrated version of the [11] model), and for merger and ringdown, attach a phenomenological waveform calibrated to ∼ 20 numerical relativity waveforms [9].…”