CLASS_GWB: robust modeling of the astrophysical gravitational wave background anisotropies

TL;DR

This paper introduces CLASS_GWB, a comprehensive computational framework for modeling and analyzing the anisotropies of the astrophysical gravitational wave background, incorporating source modeling, cosmological effects, and detector characteristics.

Contribution

The work presents a new detailed computational tool, CLASS_GWB, for calculating gravitational wave background anisotropies considering astrophysical sources and cosmological perturbations.

Findings

Computed the angular power spectrum of GW background anisotropies in LIGO-Virgo band.

Developed a versatile code applicable to various sources and frequency bands.

Provided a framework for analyzing GW maps from resolved events.

Abstract

Gravitational radiation offers a unique possibility to study the large-scale structure of the Universe, gravitational wave sources and propagation in a completely novel way. Given that gravitational wave maps contain a wealth of astrophysical and cosmological information, interpreting this signal requires a non-trivial multidisciplinary approach. In this work we present the complete computation of the signal produced by compact object mergers accounting for a detailed modelling of the astrophysical sources and for cosmological perturbations. We develop the CLASS_GWB code, which allows for the computation of the anisotropies of the astrophysical gravitational wave background, accounting for source and detector properties, as well as effects of gravitational wave propagation. We apply our numerical tools to robustly compute the angular power spectrum of the anisotropies of the gravitational wave background generated by astrophysical sources in the LIGO-Virgo frequency band. The end-to-end theoretical framework we present can be easily applied to different sources and detectors in other frequency bands. Moreover, the same numerical tools can be used to compute the anisotropies of gravitational wave maps of the sky made using resolved events.