Probing the low-mass end of the companion mass function for O-type stars M. Reggiani, A. Rainot, H. Sana, L. A. Almeida, S. Caballero-Nieves, K. Kratter, S. Lacour, J.-B. Le Bouquin and H. Zinnecker A&A, 660 (2022) A122 Published online: 25 April 2022 DOI: 10.1051/0004-6361/202142418