The SpECTRE Cauchy-characteristic evolution system for rapid, precise waveform extraction

TL;DR

The paper introduces a new Cauchy-characteristic evolution system in SpECTRE that enhances waveform extraction accuracy, speed, and flexibility for gravitational wave simulations and data analysis.

Contribution

It presents a novel, improved CCE system integrated into SpECTRE that is more modular, faster, and free of gauge-related convergence issues, applicable both during simulations and as a standalone tool.

Findings

Spectral convergence is preserved due to elimination of pure-gauge logarithms.

The system efficiently extracts all five Weyl scalars, news, and strain.

Improvements in modularity, ease of use, and computational speed over previous implementations.

Abstract

We give full details regarding the new Cauchy-characteristic evolution (CCE) system in SpECTRE. The implementation is built to provide streamlined flexibility for either extracting waveforms during the process of a SpECTRE binary compact object simulation, or as a standalone module for extracting waveforms from worldtube data provided by another code base. Using our recently presented improved analytic formulation, the CCE system is free of pure-gauge logarithms that would spoil the spectral convergence of the scheme. It gracefully extracts all five Weyl scalars, in addition to the news and the strain. The SpECTRE CCE system makes significant improvements on previous implementations in modularity, ease of use, and speed of computation.