Abstract

Gravitational wave events detected by the LIGO-Virgo-KAGRA (LVK) collaboration are the result of compact binary mergers which produce gravitational wave (GW) emission. The observed waveform carries information about the source properties, such as masses, spins, and orbital eccentricity. Events harboring eccentricity upon entrance of the LVK sensitivity band at 10 Hz are believed to have been formed through dynamical channels, where the binary has interacted with other astrophysical objects leading to a merger faster than an isolated binary. Therefore, the identification of eccentric gravitational wave events and accurate determination of their parameters is vital to understanding the population of binary black holes that form and merge dynamically. In consideration of this, we have analyzed LVK gravitational wave events that have shown evidence of eccentricity, from both the literature and our own analysis using the effective-one-body model TEOBResumS, and confronted them independently with an analysis using full numerically generated waveforms from our bank of nearly two thousand simulations of binary black holes. We have used RIFT for Bayesian parameter estimation for both the model-based and numerical relativity (NR) analyses, where results from the model-based analysis are used to generate new targeted NR simulations in the highest likelihood region of parameter space as determined by the model-based analysis. Using the full bank of simulations (including the targeted simulations) we found through a kernel density estimate of the RIFT produced posteriors that GW200208_22 favors eccentricities e20 = 0.198(+0.119/−0.180) upon entering the LVK sensitivity band at 20 Hz within a 90% credible interval. Due to our method of generating targeted simulations at the intrinsic parameters of peak likelihood models, we have found that numerical relativity waveforms return a general improvement of likelihood for waveforms of the same intrinsic parameters. For GW200208_22 we find a new peak likelihood waveform, compared to model-based analysis, with an estimated eccentricity at 20 Hz, e20 = 0.200, thus reinforcing the eccentric hypothesis of the binary. We have also used our full bank of numerical waveforms on GW190620 finding that the KDE estimate favors eccentricities at 10 Hz in e10 = 0.190(+0.046/−0.186). However, new specifically targeted simulations will be required to narrow this eccentricity range.

Publication Date

2-26-2026

Document Type

Thesis

Student Type

Graduate

Degree Name

Astrophysical Sciences and Technology (MS)

Department, Program, or Center

Physics and Astronomy, School of

College

College of Science

Advisor

Carlos Lousto

Advisor/Committee Member

Richard O’Shaughnessy

Advisor/Committee Member

Yosef Zlochower

Campus

RIT – Main Campus

Download

Share

COinS