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

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 نشر من قبل Kiril Stoyanov
 تاريخ النشر 2014
  مجال البحث فيزياء
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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 $lambda$6678 AA line is modeled with an orbital period P$_{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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