LEGWORK: A python package for computing the evolution and detectability of stellar-origin gravitational-wave sources with space-based detectors

TL;DR

LEGWORK is an open-source Python package designed to predict the evolution and detectability of stellar-origin gravitational wave sources for space-based detectors like LISA, facilitating large-scale population studies.

Contribution

It introduces a versatile, efficient tool for modeling orbital evolution and gravitational wave signals from various stellar systems, addressing gaps in existing literature and enabling large population analyses.

Findings

Efficiently models orbital evolution and gravitational wave signals.

Supports a wide range of stellar-origin sources including binaries with white dwarfs, neutron stars, and black holes.

Clarifies discrepancies in existing literature on gravitational wave source modeling.

Abstract

We present LEGWORK (LISA Evolution and Gravitational Wave Orbit Kit), an open-source Python package for making predictions about stellar-origin gravitational wave sources and their detectability in LISA or other space-based gravitational wave detectors. LEGWORK can be used to evolve the orbits of sources due to gravitational wave emission, calculate gravitational wave strains (using post-Newtonian approximations), compute signal-to-noise ratios and visualise the results. It can be applied to a variety of potential sources, including binaries consisting of white dwarfs, neutron stars and black holes. Although we focus on double compact objects, in principle LEGWORK can be used for any system with a user-specified orbital evolution, such as those affected by a third object or gas drag. We optimised the package to make it efficient for use in population studies which can contain tens-of-millions of sources. This paper describes the package and presents several potential use cases. We explain in detail the derivations of the expressions behind the package as well as identify and clarify some discrepancies currently present in the literature. We hope that LEGWORK will enable and accelerate future studies triggered by the rapidly growing interest in gravitational wave sources.