Dynamical mass of the O-type supergiant in ζ Orionis A

  title={Dynamical mass of the O-type supergiant in $\zeta$ Orionis A},
  author={C. Hummel and T. Rivinius and M. Nieva and O. Stahl and G. Belle and R. Zavala},
  journal={Astronomy and Astrophysics},
Aims. A close companion ofζ Orionis A was found in 2000 with the Navy Precision Optical Interferometer (NPOI), and shown to be a physical companion. Because the primary is a supergiant of type O, for which dynamical mass measurements are very rare, the companion was observed with NPOI over the full 7-year orbit. Our aim was to determine the dynamical mass of a supergiant that, due to the physical separation of more than 10 AU between the components, cannot have undergone mass exchange with the… Expand

Figures and Tables from this paper

Orbits, Distance, and Stellar Masses of the Massive Triple Star Sigma Orionis
We present interferometric observations of the sigma Orionis triple system using the CHARA Array, NPOI, and VLTI. Using these measurements, we spatially resolve the orbit of the close spectroscopicExpand
Studying the photometric and spectroscopic variability of the magnetic hot supergiant ζ Orionis Aa
Massive stars play a significant role in the chemical and dynamical evolution of galaxies. However, much of their variability, particularly during their evolved supergiant stage, is poorlyExpand
Discovery of magnetic A supergiants: the descendants of magnetic main-sequence B stars
In the context of the high resolution, high signal-to-noise ratio, high sensitivity, spectropolarimetric survey BritePol, which complements observations by the BRITE constellation of nanosatellitesExpand
Super-Fast Line-Profile Variability in the Spectra of OBA Stars. IV: ζ Ori A
Absctract —The present study continues the investigation of the super-fast variability of line profiles in the spectra of stars of early spectral types. We studied the line-profile variability in theExpand
The magnetic field of ζ Orionis A
Zeta Ori A is a hot star claimed to host a weak magnetic field, but no clear magnetic detection was obtained so far. In addition, it was recently shown to be a binary system composed of a O9.5IExpand
Optical and Near-infrared Spectra of σ Orionis Isolated Planetary-mass Objects
We have obtained low-resolution optical (0.7-0.98 micron) and near-infrared (1.11-1.34 micron and 0.8-2.5 micron) spectra of twelve isolated planetary-mass candidates (J = 18.2-19.9 mag) of the 3-MyrExpand
We report on both high-precision photometry from the Microvariability and Oscillations of Stars (MOST) space telescope and ground-based spectroscopy of the triple system δ Ori A, consisting of aExpand
The magnetic field of ζ Ori A
Abstract Magnetic fields play a significant role in the evolution of massive stars. About 7% of massive stars are found to be magnetic at a level detectable with current instrumentation (Wade et al.Expand
Angular Sizes, Radii, and Effective Temperatures of B-type Stars from Optical Interferometry with the CHARA Array
We present interferometric observations of 25 spectral type-B stars that were made with the Precision Astronomical Visible Observations and the CLassic Interferometry with Multiple Baselines beamExpand
Improving the surface brightness-color relation for early-type stars using optical interferometry
The aim of this work is to improve the SBC relation for early-type stars in the $-1 \leq V-K \leq 0$ color domain, using optical interferometry. Observations of eight B- and A-type stars were securedExpand


The weak magnetic field of the O9.7 supergiant ζ Orionis A
We report here the detection of a weak magnetic field of 50-100 G on the O9.7 supergiant ζ Orionis A (ζ Ori A), using spectropolarimetric observations obtained with NARVAL at the 2-m TBernard LyotExpand
Tracing the young massive high-eccentricity binary system Theta 1 Orionis C through periastron passage
Context. The nearby high-mass star binary system θ 1 Ori C is the brightest and most massive of the Trapezium OB stars at the core of the Orion Nebula Cluster, and it represents a perfect laboratoryExpand
ζ Orionis A is a Double Star
A close, 4th magnitude companion to ζ Orionis A has been resolved with the Navy Prototype Optical Interferometer at Lowell Observatory. This confirms an indication of multiplicity from observationsExpand
Observational effects of magnetism in O stars: surface nitrogen abundances ,
Aims. We investigate the surface nitrogen content of the six magnetic O stars known to date as well as of the early B-type star τ Sco. We compare these abundances to predictions of evolutionaryExpand
9 Sagittarii: uncovering an O-type spectroscopic binary with an 8.6 year period
Context. The O-type object 9 Sgr is a well-known synchrotron radio emitter. This feature is usually attributed to colliding-wind binary systems, but 9 Sgr was long considered a single star. Aims. WeExpand
The interstellar Ca II distance scale
Aims. We attempt to extend the relation between the strengths of the interstellar Ca ii lines and the distances to early-type stars to objects beyond 1 kiloparsec, with the line saturation taken intoExpand
Temperature, gravity, and bolometric correction scales for non-supergiant OB stars
Context. Precise and accurate determinations of the atmospheric parameters effective temperature and surface gravity are mandatory to derive reliable chemical abundances in OB stars. Furthermore,Expand
Validation of the new Hipparcos reduction
Context. A new reduction of the astrometric data as produced by the Hipparcos mission has been published, claiming accuracies for nearly all stars brighter than magnitude Hp = 8 to be better, by upExpand
On the Hipparcos parallaxes of O stars
We compare the absolute visual magnitude of the majority of bright O stars in the sky as predicted from their spectral type with the absolute magnitude calculated from their apparent magnitude andExpand
Accurate masses and radii of normal stars: modern results and applications
This article presents and discusses a critical compilation of accurate, fundamental determinations of stellar masses and radii. We have identified 95 detached binary systems containing 190 stars (94Expand