2016/02/24 by P. Scicluna, Peter Scicluna, S. Wolf +7 · 9 citations
Physics and Astronomy · #Accretion (finance) #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Astrophysics and Star Formation Studies #Binary number #Binary star #Binary system #Galaxy #Infrared #Luminosity #Optics #Physics #Radiative transfer #Spectral energy distribution #Star formation #Stars #Stellar, planetary, and galactic studies #T Tauri star #Young stellar object #astro-ph.EP #astro-ph.SR
paper · pdf · doi:10.1093/mnras/stw460
published in Monthly Notices of the Royal Astronomical Society 458(3), 2476-2491 (Oxford University Press) · 17 pages, 11 figures, 4 tables. Recommended for acceptance to MNRAS
arxiv created 2016/02/24 · openalex publication_date 2016/03/01 · arxiv updated 2016/03/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Given that a majority of stars form in multiple systems, in order to fully understand the star- and planet-formation processes we must seek to understand them in multiple stellar systems. With this in mind, we present an analysis of the enigmatic binary T-Tauri system VV Corona Australis, in which both components host discs, but only one is visible at optical wavelengths. We seek to understand the peculiarities of this system by searching for a model for the binary which explains all the available continuum observations of the system. We present new mid-infrared interferometry and near-infrared (NIR) spectroscopy along with archival millimetre-wave observations, which resolve the binary at 1.3 mm for the first time. We compute a grid of pre-main-sequence radiative transfer models and calculate their posterior probabilities given the observed spectral energy distributions and mid-infrared interferometric visibilities of the binary components, beginning with the assumption that the only differences between the two components are their inclination and position angles. Our best-fitting solution corresponds to a relatively low-luminosity T-tauri binary, with each component's disc having a large scaleheight and viewed at moderate inclination (∼50°), with the infrared companion inclined by ∼5° more than the primary. Comparing the results of our model to evolutionary models suggests stellar masses ∼1.7 M⊙ and an age for the system of 3.5 Myr, towards the upper end of previous estimates. Combining these results with accretion indicators from NIR spectroscopy, we determine an accretion rate of 4.0 × 10−8 M⊙ yr−1 for the primary. We suggest that future observations of VV Corona Australis and similar systems should prioritize high angular resolution sub-mm and NIR imaging of the discs and high-resolution optical/NIR spectroscopy of the central stars.