On dust evolution in planet-forming discs in binary systems. II -- Comparison with Taurus and $\rho$ Ophiuchus (sub-)millimetre observations: discs in binaries have small dust sizes

Abstract

The recently discovered exoplanets in binary or higher-order multiple stellar systems sparked a new interest in the study of proto-planetary discs in stellar aggregations. Here we focus on disc solids, as they make up the reservoir out of which exoplanets are assembled and dominate (sub-)millimetre disc observations. These observations suggest that discs in binary systems are fainter and smaller than in isolated systems. In addition, disc dust sizes are consistent with tidal truncation only if they orbit very eccentric binaries. In a previous study we showed that the presence of a stellar companion hastens the radial migration of solids, shortening disc lifetime and challenging planet formation. In this paper we confront our theoretical and numerical results with observations: disc dust fluxes and sizes from our models are computed at ALMA wavelengths and compared with Taurus and $\rho$ Ophiuchus data. A general agreement between theory and observations is found. In particular, we show that the dust disc sizes are generally smaller than the binary truncation radius due to the combined effect of grain growth and radial drift: therefore, small disc sizes do not require implausibly high eccentricities to be explained. Furthermore, the observed binary discs are compatible within $1\sigma$ with a quadratic flux-radius correlation similar to that found for single-star discs and show a close match with the models. However, the observational sample of resolved binary discs is still small and additional data are required to draw more robust conclusions on the flux-radius correlation and how it depends on the binary properties.

20 pages, 10 figures; accepted for publication in MNRAS

References in corpus (25)

• Array Programming with NumPy
• New evolutionary models for pre-main sequence and main sequence low-mass stars down to the hydrogen-burning limit
• Some Aspects of Measurement Error in Linear Regression of Astronomical Data
• An Optical Spectroscopic Study of T Tauri Stars. I. Photospheric Properties
• emcee v3: A Python ensemble sampling toolkit for affine-invariant MCMC
• Chemical enrichment of giant planets and discs due to pebble drift
• A Millimeter Continuum Size-Luminosity Relationship for Protoplanetary Disks
• One Solution to the Mass Budget Problem for Planet Formation: Optically Thick Disks with Dust Scattering
• Different dust and gas radial extents in protoplanetary disks: consistent models of grain growth and CO emission
• Physical properties of dusty protoplanetary disks in Lupus: evidence for viscous evolution?
• Measurement of Circumstellar Disk Sizes in the Upper Scorpius OB Association with ALMA
• Protoplanetary Disks in $\rho$ Ophiuchus as Seen From ALMA
• The time evolution of dusty protoplanetary disc radii: observed and physical radii differ
• The Ophiuchus DIsk Survey Employing ALMA (ODISEA): Disk Dust Mass Distributions across Protostellar Evolutionary Classes
• Tidal Torques on Misaligned Disks in Binary Systems
• Size and structures of disks around very low mass stars in the Taurus star-forming region
• Dynamical Masses of Low Mass Stars in the Taurus and Ophiuchus Star Forming Regions
• Orbits and Masses in the T Tauri System
• Demographics of disks around young very low-mass stars and brown dwarfs in Lupus
• The evolution of photo-evaporating viscous discs in binaries
• Planets in Binaries: Formation and Dynamical Evolution
• On the millimetre continuum flux-radius correlation of proto-planetary discs
• On dust evolution in planet-forming discs in binary systems. I -- Theoretical and numerical modelling: radial drift is faster in binary discs
• The effect of stellar multiplicity on protoplanetary discs. A NIR survey of the Lupus star forming region
• The Effect of Binarity on Circumstellar Disk Evolution