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Interferometry and spectroscopy of Beta Cen: a Beta Cephei star in a binary system

J. G. Robertson·T. R. Bedding·C. Aerts·C. Waelkens·R. G. Marson·J. R. Barton
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Abstract

Beta Cen is a bright Beta Cephei variable and has long been suspected to be a binary. Here we report interferometric observations with the 3.9-m Anglo-Australian Telescope at a single epoch which show the star to be a binary with components separated by 15 milliarcsec and having approximately equal luminosities at 486 nm. We also present high-resolution spectra taken over five nights with the ESO CAT which show Beta Cen to be a double-lined spectroscopic binary. We identify two pulsation frequencies in the primary. Further spectroscopic and interferometric studies of this double star should allow determination of its orbital parameters and component masses.

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J. G. Robertson, T. R. Bedding, C. Aerts, C. Waelkens, R. G. Marson, J. R. Barton. 1998-09-15. Interferometry and spectroscopy of Beta Cen: a Beta Cephei star in a binary system. https://doi.org/10.1046/j.1365-8711.1999.02068.x

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