We report about an ongoing photometric and spectroscopic monitoring survey of about 250 O- and 540 B-type stars in the southern Milky Way with the aim to determine the fraction of close binary systems as a function of mass and to determine the physical parameters of the individual components in the multiple systems. Preliminary results suggest that the multiplicity rate drops from 80% for the highest masses to 20% for stars of 3 solar masses. Our analysis indicates that the binary systems often contain close pairs with components of similar mass. This coincidence cannot originate from a random tidal capture in a dense cluster but is likely due to a particular formation process for high-mass stars. The large percentage of multiple systems requires a new photometric calibration for the absolute magnitudes of O-type stars.
@article{arxiv.1306.1811,
title = {The Multiplicity of High-Mass Stars},
author = {R. Chini and A. Barr and L. S. Buda and T. Dembsky and H. Drass and A. Nasseri and V. H. Hoffmeister and K. Fuhrmann},
journal= {arXiv preprint arXiv:1306.1811},
year = {2013}
}
Comments
16 pages, 6 figures, Cent. Eur. Astrophys. Bull. 37 (2013), in press. arXiv admin note: substantial text overlap with arXiv:1205.5238