High resolution optical spectroscopy of Plaskett's star

Abstract

We present here the analysis of an extensive set of high resolution optical spectra of Plaskett's star (HD 47129). We use a disentangling method to separate the individual spectra of each star. We derive a new orbital solution and discuss the spectral classification of both components. A Doppler tomography technique applied to the emission lines H alpha and He II 4686 yields a Doppler map that illustrates the wind interactions in the system. Finally, an atmosphere code is used to determine the different chemical abundances of the system components and the wind parameters. HD 47129 appears to be an O8 III/I + O7.5 III binary system in a post RLOF evolutionary stage, where matter has been transferred from the primary to the secondary star. The He overabundance of the secondary supports this scenario. In addition, the N overabundance and C underabundance of the primary component confirm previous results based on X-ray spectroscopy and indicate that the primary is an evolved massive star. Furthermore, the secondary star has a large rotational velocity that deforms its surface, leading to a non-uniform distribution in effective temperature. This could explain the variations in the equivalent widths of the secondary lines with phase. We suggest that the wind of the secondary star is confined near the equatorial plane because of its high rotational velocity, affecting the ram pressure equilibrium in the wind interaction zone.

Accepted in A & A

References in corpus (9)

• A new calibration of stellar parameters of Galactic O stars
• Stellar evolution with rotation VIII: Models at Z = 10^{-5} and CNO yields for early galactic evolution
• Stellar evolution with rotation X: Wolf-Rayet star populations at solar metallicity
• UBVJHK synthetic photometry of Galactic O stars
• The VLT-FLAMES survey of massive stars: rotation and nitrogen enrichment as the key to understanding massive star evolution
• The most massive stars in the Arches cluster
• Constraining the mass transfer in massive binaries through progenitor evolution models of Wolf-Rayet+O binaries
• Fourier method in the determination of rotational velocities in OB stars
• The Struve-Sahade effect in the optical spectra of O-type binaries I. Main-sequence systems

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