wolensing: A Python package for computing the amplification factor for gravitational waves with wave-optics effects

TL;DR

wolensing is an open-source Python package that computes gravitational wave lensing amplification factors with wave-optics effects, enabling accurate waveform modeling and visualization across various lens models and frequency regimes.

Contribution

It introduces a comprehensive tool integrating wave-optics calculations with lens modeling, including GPU support and visualization features, enhancing gravitational wave lensing analysis.

Findings

Accurately computes amplification factors including diffractive effects.

Supports multiple lens models with GPU acceleration.

Provides visualization of time delay contours.

Abstract

The wolensing Python package offers a solution for gravitational wave lensing computations within the full wave-optics regime. This tool is primarily designed to calculate the gravitational lensing amplification factor including diffractive effects, an essential component for generating accurate lensed gravitational wave waveforms. These waveforms are integral to astrophysical and cosmological studies related to gravitational-wave lensing. Integrating with lensingGW (Pagano, Hannuksela, and Li 2020), wolensing provides solutions for image positions in the high-frequency regime where wave and geometrical optics converge. This functionality allows the amplification factor to be applicable across a wider frequency range. Another key feature of wolensing is its ability to plot time delay contours on the lens plane, offering researchers a visual tool to better understand the relationship between the lens system and the amplification factor. wolensing is compatible with various lens models in lenstronomy (Birrer et al. 2021). There are also built-in lens models including point mass, singular isothermal sphere (SIS),and nonsingular isothermal ellipsoid (NIE) with jax (Bradbury et al. 2018) supporting GPU computation. Users can accommodate different lens models in the code with jax. wolensing is available as an open-source package on PyPI and can be installed via pip.