tgr 1.1.0

A waveform plugin for PyCBC with non-general relativity templates

TGR: Testing General Relativity with Gravitational Waves

TGR is a collection of PyCBC waveform plugins for testing general relativity with gravitational-wave data. It provides waveform approximants for modified propagation, phenomenological beyond-GR corrections, ringdown models. The package is intended for analyses that call waveforms through the PyCBC waveform plugin interface, can be used for Bayesian parameter estimation, matched-filtering, injection campaigns, etc.

Installation

TGR is published on PyPI as tgr:

pip install tgr

For development from a local checkout:

git clone https://github.com/yi-fan-wang/TestingGR_with_Gravwaves.git
cd TestingGR_with_Gravwaves
pip install -e .

The package requires Python 3.11 or newer and installs PyCBC as a dependency.

Waveform Plugins

After installation, TGR registers the following PyCBC approximants.

Frequency-domain waveform plugins:

• birefringence: gravitational-wave birefringence models
• massive_graviton: massive-graviton propagation corrections
• fta: flexible theory-agnostic waveform deformations
• ppe: parameterized post-Einsteinian corrections
• lsa: line-of-sight amplitude corrections

Time-domain waveform plugins:

• nrsxs: SXS numerical-relativity waveform interface
• lvcnr: LIGO/Virgo/KAGRA numerical-relativity waveform interface
• NRSur7dq4_remove_qqnm: NRSur7dq4 waveform with quadratic QNM contributions removed
• NRSur7dq4_tdtaper: tapered NRSur7dq4 waveform generation

Documentation and Examples

Documentation is available at yi-fan-wang.github.io/TestingGR_with_Gravwaves. Example notebooks and scripts are available in the examples directory.

Usage in Scientific Publications

The birefringence is used in Refs.[1,2] for testing gravitational wave parity violation. The NRSur7dq4_remove_qqnm approximant is designed for subtracting predicted quadratic quasi-normal-mode contributions from an NRSur7dq4 waveform and used in the analysis of nonlinear ringdown evidence in GW250114 [3].

References

[1] Tests of Gravitational-Wave Birefringence with the Open Gravitational-Wave Catalog. arXiv:2109.09718.

[2] Gravitational-Wave Implications for the Parity Symmetry of Gravity at GeV Scale. arXiv:2002.05668.

[3] A nonlinear voice from GW250114 ringdown. arXiv:2601.05734.