The origin of very wide binary systems
Abstract
The majority of stars in the Galactic field and halo are part of binary or multiple systems. A significant fraction of these systems have orbital separations in excess of thousands of astronomical units, and systems wider than a parsec have been identified in the Galactic halo. These binary systems cannot have formed through the 'normal' star-formation process, nor by capture processes in the Galactic field. We propose that these wide systems were formed during the dissolution phase of young star clusters. We test this hypothesis using N-body simulations of evolving star clusters and find wide binary fractions of 1-30%, depending on initial conditions. Moreover, given that most stars form as part of a binary system, our theory predicts that a large fraction of the known wide 'binaries' are, in fact, multiple systems.
Cite
@article{arxiv.0910.5796,
title = {The origin of very wide binary systems},
author = {M. B. N. Kouwenhoven and S. P. Goodwin and Richard J. Parker and M. B. Davies and D. Malmberg and P. Kroupa},
journal= {arXiv preprint arXiv:0910.5796},
year = {2015}
}
Comments
4 pages, 1 figure, to appear in the proceedings of IAU Symposium 266, eds. R. de Grijs & J.R.D. Lepine