%0 Journal Article
%A Cappelluti, Nico
%A Pacucci, Fabio
%A Hasinger, Günther Gustav
%T Constraining Wind-driven Accretion onto Gaia BH3 with Chandra
%J The astrophysical journal / Part 1
%V 973
%N 2
%@ 0004-637X
%C London
%I Institute of Physics Publ.
%M PUBDB-2024-07605
%M arXiv:2406.07602
%P 75
%D 2024
%Z Accepted for publication in The Astrophysical Journal. 10 pages, 4 figures
%X Gaia BH3 is the most massive known stellar-origin black hole in the Milky Way, with a mass M<sub>•</sub> ≈ 33 M<sub>⊙</sub>. Detected from Gaia’s astrometry, this black hole is in the mass range of those observed via gravitational waves, whose nature is still highly debated. Hosted in a binary system with a companion giant star that is too far away for Roche-lobe mass transfer, this black hole could nonetheless accrete at low levels due to wind-driven mass loss from its companion star, thus accreting in advection-dominated accretion flow, or ADAF, mode. Using stellar wind models, we constrain its Eddington ratio in the range 10<sup>−9</sup> < f<sub>Edd</sub> < 10<sup>−7</sup>, corresponding to radiative efficiencies 5 × 10<sup>−5</sup> < ϵ < 10<sup>−3</sup>, compatible with radiatively inefficient accretion modes. Chandra ACIS-S observed this object and obtained the most sensitive upper bound of its [2–10] keV flux: F<sub>X</sub> < 3.25 × 10<sup>−15</sup> erg s<sup>−1</sup> cm<sup>−2</sup> at 90
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:001317245800001
%R 10.3847/1538-4357/ad6f96
%U https://bib-pubdb1.desy.de/record/619400