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arXiv · 1411.7561

Orbital parameters of the high-mass X-ray binary 4U 2206+54

K. A. Stoyanov·R. K. Zamanov·G. Y. Latev·A. Y. Abedin·N. A. Tomov
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Abstract

We present new radial velocities of the high-mass X-ray binary star 4U 2206+54 based on optical spectra obtained with the Coude spectrograph at the 2m RCC telescope at the Rozhen National Astronomical Observatory, Bulgaria in the period November 2011 -- July 2013. The radial velocity curve of the HeI $λ$6678 Å line is modeled with an orbital period P$_{orb}$ = 9.568~d and an eccentricity of $e$ = 0.3. These new measurements of the radial velocity resolve the disagreements of the orbital period discussions.

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K. A. Stoyanov, R. K. Zamanov, G. Y. Latev, A. Y. Abedin, N. A. Tomov. 2014-11-27. Orbital parameters of the high-mass X-ray binary 4U 2206+54. https://doi.org/10.1002/asna.201412127

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