The first high-amplitude delta Scuti star in an eclipsing binary system
Abstract
We report the discovery of the first high-amplitude delta Scuti star in an eclipsing binary, which we have designated UNSW-V-500. The system is an Algol-type semi-detached eclipsing binary of maximum brightness V = 12.52 mag. A best-fitting solution to the binary light curve and two radial velocity curves is derived using the Wilson-Devinney code. We identify a late A spectral type primary component of mass 1.49+/-0.02 M_sun and a late K spectral type secondary of mass 0.33+/-0.02 M_sun, with an inclination of 86.5+/-1.0 degrees, and a period of 5.3504751+/-0.0000006 d. A Fourier analysis of the residuals from this solution is performed using PERIOD04 to investigate the delta Scuti pulsations. We detect a single pulsation frequency of f_1 = 13.621+/-0.015 c/d, and it appears this is the first overtone radial mode frequency. This system provides the first opportunity to measure the dynamical mass for a star of this variable type; previously, masses have been derived from stellar evolution and pulsation models.
Cite
@article{arxiv.0707.4540,
title = {The first high-amplitude delta Scuti star in an eclipsing binary system},
author = {J. L. Christiansen and A. Derekas and M. C. B. Ashley and J. K. Webb and M. G. Hidas and D. W. Hamacher and L. L. Kiss},
journal= {arXiv preprint arXiv:0707.4540},
year = {2009}
}
Comments
7 pages, 6 figures, 2 tables, for submission to MNRAS, v2: paper size change, small typographical changes to abstract