Chase Orbits, Not Time: A Scalable Paradigm for Long-Duration Eccentric Gravitational-Wave Surrogates

Area of Science:

• Astrophysics
• Gravitational-wave astronomy
• Computational physics

Background:

• Orbital eccentricity is crucial for understanding compact binary origins.
• Current gravitational-wave analyses omit eccentricity due to high computational costs of generating eccentric waveforms.
• Accurate surrogate models for long, eccentric waveforms are challenging to create.

Purpose of the Study:

• To develop a novel and efficient surrogate modeling technique for long-duration eccentric binary black hole waveforms.
• To reduce the computational cost associated with generating eccentric template waveforms.
• To enable routine inclusion of orbital eccentricity in gravitational-wave data analysis.

Main Methods:

• Introduced a new surrogate building technique utilizing mean anomaly instead of time for waveform modeling.
• Modeled intermediate eccentric waveform data pieces using mean anomaly to simplify harmonic content.
• Expressed waveform data variations using instantaneous orbital eccentricity and mean anomaly for easier parametric fitting.

Main Results:

• Achieved significantly more compressed surrogates compared to standard time-based parametrizations.
• Developed InspiralESIGMASur, a long nonspinning surrogate for eccentric waveforms (2.77x10^6 M, 850-1250 orbits).
• Demonstrated the feasibility of building long-duration eccentric surrogates for current and future gravitational-wave detectors.

Conclusions:

• The novel mean anomaly-based parametrization offers a highly efficient approach to surrogate modeling of eccentric waveforms.
• This technique overcomes previous computational barriers, making eccentric binary black hole analysis practical.
• The developed methods pave the way for incorporating orbital eccentricity in gravitational-wave data analysis across multiple detector generations.