Dispersal of protoplanetary disks by wind stripping

Department of Terrestrial Magnetism, Carnegie Institution of Washington, Washington, DC, USA

Corresponding author: matsuyama@dtm.ciw.edu

Abstract

We present a model for the dispersal of protoplanetary disks by winds from either the central star or the inner disk. These winds obliquely strike the flaring disk surface and strip away disk material by entraining it in an outward radial-moving flow at the disk-wind interface. This interface lies several disk scale heights above the mid plane. The disk dispersal time depends on the velocity at which disk material flows into the mixing layer. If this velocity is ~10% of the sound speed, the disk dispersal time at ~1–10 AU is ~5 Myr for a 0.01 M_๏ disk around a solar mass star, with a spherical wind launched from the inner disk or central star with a typical mass loss rate of 10^-8 M_๏yr^-1 and terminal velocity of v_w = 100 kms^-1. We conclude that wind stripping is not a dominant disk dispersal mechanism compared with viscous accretion and photoevaporation. Nevertheless, wind stripping may affect the evolution of the intermediate disk regions.