Towards a consistent model of the hot quadruple system HD 93206 = QZ Carinæ: II. N-body model

Abstract

HD 93206 is early-type massive stellar system, composed of components resolved by direct imaging (Ab, Ad, B, C, D) as well as a compact sub-system (Aa1, Aa2, Ac1, Ac2). Its geometry was already determined on the basis of extensive photometric, spectroscopic and interferometric observations. However, the fundamental absolute parameters are still not known precisely enough. We use an advanced N-body model to account for all mutual gravitational perturbations among the four close components, and all observational data types, including: astrometry, radial velocities, eclipse timing variations, squared visibilities, closure phases, triple products, normalized spectra, and spectral-energy distribution (SED). The respective model has 38 free parameters, namely three sets of orbital elements, component masses, and their basic radiative properties ($T$, $\log g$, $v_{\mathrm{rot}}$). We revised the fundamental parameters of QZ Car as follows. For a model with the nominal extinction coefficient $R_V\equiv A_V/E(B-V)=3.1$, the best-fit masses are $m_1=26.1M_{\mathrm{S}}$, $m_2=32.3M_{\mathrm{S}}$, $m_3=70.3M_{\mathrm{S}}$, $m_4=8.8M_{\mathrm{S}}$, with uncertainties of the order of $2M_{\mathrm{S}}$, and the system distance $d=(2800\pm 100)\mathrm{pc}$. In an alternative model, where we increased the weights of RV and TTV observations and relaxed the SED constraints, because extinction can be anomalous with $R_V\sim 3.4$, the distance is smaller, $d=(2450\pm 100)\mathrm{pc}$. This would correspond to that of Collinder 228 cluster. Independently, this is confirmed by dereddening of the SED, which is only then consistent with the early-type classification (O9.7Ib for Aa1, O8III for Ac1). Future modelling should also account for an accretion disk around Ac2 component.

arXiv commentA&A, submitted

References in corpus (23)

• Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
• Modules for Experiments in Stellar Astrophysics (MESA): Binaries, Pulsations, and Explosions
• A 3D Dust Map Based on Gaia, Pan-STARRS 1 and 2MASS
• A Grid of NLTE Line-Blanketed Model Atmospheres of O-type Stars
• Automated data reduction workflows for astronomy
• A Grid of NLTE Line-Blanketed Model Atmospheres of Early B-type Stars
• The AKARI/IRC Mid-Infrared All-Sky Survey
• Southern Massive Stars at High Angular Resolution: Observational Campaign and Companion Detection
• First Light for GRAVITY: Phase Referencing Optical Interferometry for the Very Large Telescope Interferometer
• Gaia-2MASS 3D maps of Galactic interstellar dust within 3 kpc
• Physics of Eclipsing Binaries. V. General Framework for Solving the Inverse Problem
• XHIP: An Extended Hipparcos Compilation
• Quantification of tidal parameters from Solar system data
• Light-echoes from the plateau in Eta Carinae's Great Eruption reveal a two-stage shock-powered event
• (216) Kleopatra, a low density critically rotating M-type asteroid
• Gaia EDR3 distances of the young stellar clusters in the extended Carina Nebula complex
• Distances to Galactic OB-stars: Photometry vs. Parallax
• An advanced multipole model for (216) Kleopatra triple system
• Optically thin circumstellar medium in $\beta$ Lyr A system
• Tidal Love numbers and moment-Love relations of polytropic stars
• An advanced N-body model for interacting multiple stellar systems
• GRAVITY spectro-interferometric study of the massive multiple stellar system HD 93 206 A
• Towards a consistent model of the hot quadruple system HD 93206 = QZ Carinae - I. Observations and their initial analyses

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