2026/07/29 by T. Shenar, J. Bodensteiner, M. Abdul-Masih +73
Physics and Astronomy · #physics.gen-ph
paper · pdf · doi:10.18727/0722-6691/5417
published as The Messenger (ESO), Vol. 196, pp. 15-19 (2026) · 5 pages, 3 figures; published in The Messenger (ESO)
arxiv created 2026/07/29 · arxiv updated 2026/07/31
Massive stars at low metallicity (Z) play a central role in shaping the high-redshift Universe, yet their multiplicity remains poorly constrained. The Binarity at Low Metallicity (BLOeM) campaign is a two-year survey of 929 stars in the Small Magellanic Cloud with the Fibre Large Array Multi Element Spectrograph (FLAMES) instrument at ESO's Very Large Telescope, providing the first large-scale spectroscopic monitoring of massive stars at low Z (1/5 solar). Analysis of the initial nine epochs reveals high intrinsic binary fractions (>70%) on the main sequence and a steep decline in evolved objects. Analysis of the full dataset will yield orbital solutions, identify black-hole companions, and allow a derivation of the initial mass function for single and binary stars at low Z.