Improved estimates of the physical properties of the O-star binary V1007 Sco = HD 152248and notes on several other binaries in the NGC 6231 cluster

Abstract

Context.In spite of the importance of massive O-type stars for astrophysics, their accurate masses and other fundamental properties are still a matter of debate. Determining them reliably is hampered by various factors (stellar winds and other forms of circumstellar matter), and the agreement of derived properties with the model predictions is far from satisfactory. Careful studies of O-type binaries, especially of those in stellar clusters, are therefore desirable.