Unambiguous determination of gravitational waveforms from binary black hole mergers

Area of Science:

• Astrophysics
• General Relativity
• Computational Physics

Background:

• Gravitational radiation is theoretically defined at future null infinity (J+).
• Practical estimations often rely on data from finite radii, introducing potential inaccuracies.
• Accurate gravitational waveforms are crucial for understanding black hole mergers and testing general relativity.

Purpose of the Study:

• To calculate gravitational radiation precisely at future null infinity (J+).
• To obtain unambiguous merger waveforms for equal-mass, nonspinning black hole inspiral and merger events.
• To develop a general-purpose method for gravitational radiation calculation at J+.

Main Methods:

• Employed characteristic extraction to compute gravitational radiation.
• Utilized data from finite radii as input for the calculation.
• Focused on the specific scenario of two equal-mass, nonspinning black hole mergers.

Main Results:

• Successfully calculated gravitational radiation at J+ for the specified black hole merger scenario.
• Determined the first unambiguous merger waveforms for this system.
• Developed a versatile implementation applicable to other gravitational wave computations.

Conclusions:

• Characteristic extraction provides a reliable method for defining and calculating gravitational radiation at J+.
• The obtained waveforms offer a precise benchmark for gravitational wave data analysis.
• The methodology can be extended to diverse astrophysical scenarios involving compact object mergers.