2021/11/01 by Sara Saracino, S. Saracino, Sebastian Kamann +13
Engineering · Physics and Astronomy · #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Binary number #Black hole (networking) #Cluster (spacecraft) #Large Magellanic Cloud #Mechanics and Biomechanics Studies #Orbital inclination #Physics #Radial velocity #Star (game theory) #Star cluster #Stars #astro-ph.GA #astro-ph.SR
paper · pdf · doi:10.1093/mnras/stab3159
11 pages, 8 figures, 4 Tables. Accepted for publication by Monthly Notices of the Royal Astronomical Society
openalex publication_date 2021/11/01 · arxiv created 2021/11/12 · arxiv updated 2021/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
ABSTRACT We report on the detection of a black hole (NGC 1850 BH1) in the ∼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 ± 0.4 M⊙), which is starting to fill its Roche lobe and is becoming distorted. Using 17 epochs of Very Large Telescope/Multi-Unit Spectroscopic Explorer observations, we detected radial velocity variations exceeding 300 km s−1 associated with the target star, linked to the ellipsoidal variations measured by the fourth phase of the Optical Gravitational Lensing Experiment in the optical bands. Under the assumption of a semidetached system, the simultaneous modelling of radial velocity and light curves constrains the orbital inclination of the binary to 38° ± 2°, resulting in a true mass of the unseen companion of 11.1-2.4+2.1 \rm 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.