Observing dust settling and coagulation in circumstellar discs

Selected constraints from high resolution imaging

Institut für Theoretische Physik und Astrophysik, Universität zu Kiel, Leibnizstr. 15, 24118 Kiel, Germany
e-mail: jsauter@astrophysik.uni-kiel.de

Received: 30 March 2010
Accepted: 18 November 2010

Abstract

Context. Circumstellar discs are expected to be the nursery of planets. Grain growth within these discs is the first step in the planet formation process in the core-accretion gas-capture scenario.

Aims. We aim to provide selection criteria for observational quantities derived from multiwavelength imaging observations that allow us to identify dust grain growth and settling.

Methods. We define a wide-ranged parameter space of discs in various states of their evolution. Using a parametrised model set-up and radiative transfer techniques, we compute multiwavelength images of discs at different inclinations.

Results. Using millimetre and sub-millimetre images, we are in the position to constrain the process of dust grain growth and sedimentation. However, the degeneracy between parameters prohibit the same achievement using near- to mid-infrared images. Using face-on observations in the N and Q band, the sedimentation height can be constrained.