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arXiv · 2002.01946

Discovery of a low-mass companion embedded in the disk of the young massive star MWC 297 with VLT/SPHERE

M. Giulia Ubeira-Gabellini·Valentin Christiaens·Giuseppe Lodato·Mario van den Ancker·Davide Fedele·Carlo F. Manara·Daniel J. Price
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Abstract

We report the discovery of a low-mass stellar companion around the young Herbig Be star MWC 297. We performed multi-epoch high-contrast imaging in the near infrared (NIR) with the Very Large Telescope (VLT)/Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE) instrument. The companion is found at projected separation of 244.7$\pm$13.2 au and a position angle of 176.4$\pm$0.1 deg. The large separation supports formation via gravitational instability. From the spectrum, we estimate a mass of 0.1-0.5 M$_{\odot}$, the range conveying uncertainties in the extinction of the companion and in evolutionary models at young ages. The orbit coincides with a gap in the dust disk inferred from the Spectral Energy Distribution (SED). The young age ($\lesssim$ 1 Myr) and mass ratio with the central star ($\sim 0.01$) makes the companion comparable to PDS 70~b, suggesting a relation between formation scenarios and disk dynamics.

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M. Giulia Ubeira-Gabellini, Valentin Christiaens, Giuseppe Lodato, Mario van den Ancker, Davide Fedele, Carlo F. Manara, Daniel J. Price. 2020-02-05. Discovery of a low-mass companion embedded in the disk of the young massive star MWC 297 with VLT/SPHERE. https://arxiv.org/abs/2002.01946

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