On May 21, 2019 Advanced LIGO and Advanced Virgo detectors observed a gravitational-wave transient GW190521, the heaviest binary black-hole merger detected to date with the remnant mass of 142M⊙ that was published recently. This observation is the first strong evidence for the existence of intermediate-mass black holes. The significance of this observation was determined by the coherent WaveBurst (cWB) - search algorithm, which identified GW190521 with minimal assumptions on its source model. In this paper, we demonstrate the capabilities of cWB to detect binary black holes without use of the signal templates, describe the details of the GW190521 detection and establish the consistency of the model-agnostic reconstruction of GW190521 by cWB with the theoretical waveform model of a binary black hole.
@article{arxiv.2009.11336,
title = {Observing an intermediate mass black hole GW190521 with minimal assumptions},
author = {Marek Szczepanczyk and Sergey Klimenko and Brendan O'Brien and Imre Bartos and V. Gayathri and Guenakh Mitselmakher and Giovanni Prodi and Gabriele Vedovato and Claudia Lazzaro and Edoardo Milotti and Francesco Salemi and Marco Drago and Shubhanshu Tiwari},
journal= {arXiv preprint arXiv:2009.11336},
year = {2021}
}