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arXiv · 0802.1692

Preliminary Orbit of the Young Binary Haro 1-14c

G. H. Schaefer·M. Simon·L. Prato·T. Barman
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Abstract

Using the Keck Interferometer, we spatially resolved the orbit of the pre-main sequence binary, Haro 1-14c, for the first time. We present these interferometric observations along with additional spectroscopic radial velocity measurements of the components. We performed a simultaneous orbit fit to the interferometric visibilities and the radial velocities of Haro 1-14c. Based on a statistical analysis of the possible orbital solutions that fit the data, we determined component masses of M_1 = 0.96 (+0.27/-0.08) Msun and M_2 = 0.33 (+0.09/-0.02) Msun for the primary and secondary, respectively, and a distance to the system of 111 (+19/-18) pc. The distance measurement is consistent with the close distance estimates of the Ophiuchus molecular cloud. Comparing our results with evolutionary tracks suggests an age of 3-4 Myr for Haro 1-14c. With additional interferometric measurements to improve the uncertainties in the masses and distance, we expect the low-mass secondary to provide important empirical data for calibrating the theoretical evolutionary tracks for pre-main sequence stars.

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G. H. Schaefer, M. Simon, L. Prato, T. Barman. 2008-02-12. Preliminary Orbit of the Young Binary Haro 1-14c. https://doi.org/10.1088/0004-6256%2F135%2F5%2F1659

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