A black hole detected in the young massive LMC cluster NGC 1850

Saracino, S, Kamann, S, Guarcello, MG, Usher, CG, Bastian, N, Cabrera-Ziri, I, Gieles, M, Dreizler, S, Costa, GSD, Husser, T-O and Hénault-Brunet, V (2021) A black hole detected in the young massive LMC cluster NGC 1850. Monthly Notices of the Royal Astronomical Society, 511. pp. 2914-2924. ISSN 0035-8711

 Preview
Text
A black hole detected in the young massive LMC cluster NGC 1850.pdf - Published Version

We report the detection of a black hole (NGC 1850 BH1) in the $\sim$100 Myr-old massive cluster NGC~1850 in the Large Magellanic Cloud. It is in a binary system with a main-sequence turn-off star (4.9 $\pm$ 0.4 M${_\odot}$), which is starting to fill its Roche Lobe and becoming distorted. Using 17 epochs of VLT/MUSE observations we detected radial velocity variations exceeding 300 km/s associated to the target star, linked to the ellipsoidal variations measured by OGLE-IV in the optical bands. Under the assumption of a semi-detached system, the simultaneous modelling of radial velocity and light curves constraints the orbital inclination of the binary to ($38 \pm 2$)$^{\circ}$, resulting in a true mass of the unseen companion of $11.1_{-2.4}^{+2.1}$ $M_{\odot}$. This represents the first direct dynamical detection of a black hole in a young massive cluster, opening up the possibility of studying the initial mass function and the early dynamical evolution of such compact objects in high-density environments.