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arXiv · 2009.11336

Observing an intermediate mass black hole GW190521 with minimal assumptions

Marek Szczepanczyk·Sergey Klimenko·Brendan O'Brien·Imre Bartos·V. Gayathri·Guenakh Mitselmakher·Giovanni Prodi·Gabriele Vedovato·Claudia Lazzaro·Edoardo Milotti·Francesco Salemi·Marco Drago·Shubhanshu Tiwari
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Abstract

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 142$\,$M$_\odot$ 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.

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Marek Szczepanczyk, Sergey Klimenko, Brendan O'Brien, Imre Bartos, V. Gayathri, Guenakh Mitselmakher, Giovanni Prodi, Gabriele Vedovato, Claudia Lazzaro, Edoardo Milotti, Francesco Salemi, Marco Drago, Shubhanshu Tiwari. 2020-09-23. Observing an intermediate mass black hole GW190521 with minimal assumptions. https://doi.org/10.1103/physrevd.103.082002

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