The predicted orbital period distribution of the subdwarf-B (sdB) population is bi-modal with a peak at short (< 10 days) and long (> 250 days) periods. Observationally, many short-period sdB systems are indeed known. The predicted long period peak is missing and orbits have only been determined for a few long-period systems. As these predictions are based on poorly understood binary-interaction processes, it is of prime importance to confront the predictions to well-constrained observational data. We therefore initiated a monitoring program to find and characterize long-period sdB stars with the 1.2 m Mercator telescope. Here we present the results of this program.
@article{arxiv.1310.0189,
title = {Long period sdB + MS binaries with Mercator},
author = {J. Vos and R. H. Østensen and H. Van Winckel},
journal= {arXiv preprint arXiv:1310.0189},
year = {2013}
}
Comments
7 pages and 2 figures; to be published in the proceedings of the Sixth Meeting on Hot Subdwarf Stars and Related Objects