Observational constraints on dust disk sizes in tidally truncated protoplanetary disks in multiple systems in the Taurus region

¹ European Southern Observatory, Karl-Schwarzschild-Strasse 2, 85748 Garching bei München, Germany
e-mail: cmanara@eso.org
² Institute of Astronomy, University of Cambridge, Madingley Road, CB3 0HA, Cambridge, UK
³ Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871, PR China
⁴ Department of Astronomy, School of Physics, Peking University, Beijing 100871, PR China
⁵ Dipartimento di Fisica, Universita Degli Studi di Milano, Via Celoria, 16, 20133 Milano, Italy
⁶ Max-Planck-Institut für Extraterrestrische Physik, Giessenbachstrasse 1, 85748 Garching bei München, Germany
⁷ Université Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France
⁸ Max-Planck-Institut für Astronomie, Königstuhl 17, 69117 Heidelberg, Germany
⁹ Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK
¹⁰ Five College Astronomy Department, Smith College, Northampton, MA 01063, USA
¹¹ Leiden Observatory, Leiden University, PO Box 9513, 2300 RA Leiden, The Netherlands
¹² NRC Herzberg Astronomy and Astrophysics, 5071 West Saanich Road, Victoria, BC, V9E 2E7, Canada
¹³ Department of Physics and Astronomy, University of Victoria, Victoria, BC, V8P 5C2, Canada
¹⁴ Purple Mountain Observatory, Chinese Academy of Sciences, 2 West Beijing Road, Nanjing 210008, PR China
¹⁵ INAF-Osservatorio Astronomico di Roma, via di Frascati 33, 00040 Monte Porzio Catone, Italy
¹⁶ Sorbonne Université, Observatoire de Paris, Université PSL, CNRS, LERMA, 75014 Paris, France

Received: 27 May 2019
Accepted: 6 July 2019

Abstract

The impact of stellar multiplicity on the evolution of planet-forming disks is still the subject of debate. Here we present and analyze disk structures around ten multiple stellar systems that were included in an unbiased, high spatial resolution survey performed with ALMA of 32 protoplanetary disks in the Taurus star-forming region. At the unprecedented spatial resolution of ~0.12′′ we detect and spatially resolve the disks around all primary stars, and those around eight secondary and one tertiary star. The dust radii of disks around multiple stellar systems are smaller than those around single stars in the same stellar mass range and in the same region. The disks in multiple stellar systems also show a steeper decay of the millimeter continuum emission at the outer radius than disks around single stars, suggestive of the impact of tidal truncation on the shape of the disks in multiple systems. However, the observed ratio between the dust disk radii and the observed separation of the stars in the multiple systems is consistent with analytic predictions of the effect of tidal truncation only if the eccentricities of the binaries are rather high (typically >0.5) or if the observed dust radii are a factor of two smaller than the gas radii, as is typical for isolated systems. Similar high-resolution studies targeting the gaseous emission from disks in multiple stellar systems are required to resolve this question.