The complex circumstellar environment of HD142527

TL;DR

This study models the complex circumstellar environment of HD142527, revealing a three-component disk structure with distinct geometries and a significant dust mass, enhancing understanding of its evolutionary stage.

Contribution

The paper provides a detailed radiative transfer model of HD142527's disk, identifying three distinct geometrical components and their properties, which was not previously characterized in such detail.

Findings

The disk has three geometrically distinct components separated by a gap.

The inner disk extends from 0.3 to 30 AU with a flat geometry.

The outer disk is massive, self-shadowed, and extends from 130 to 200 AU.

Abstract

The recent findings of gas giant planets around young A-type stars suggest that disks surrounding Herbig Ae/Be stars will develop planetary systems. An interesting case is HD142527, for which previous observations revealed a complex circumstellar environment and an unusually high ratio of infrared to stellar luminosity. Its properties differ considerably from other Herbig Ae/Be stars. This suggests that the disk surrounding HD142527 is in an uncommon evolutionary stage. We aim for a better understanding of the geometry and evolutionary status of the circumstellar material around the Herbig Ae/Be star HD142527. We map the composition and spatial distribution of the dust around HD142527. We analyze SEST and ATCA millimeter data, VISIR N and Q-band imaging and spectroscopy. We gather additional relevant data from the literature. We use the radiative transfer code MCMax to construct a model of the geometry and density structure of the circumstellar matter, which fits all of the observables satisfactorily. We find that the disk of HD142527 has three geometrically distinct components separated by a disk gap running from 30 to 130 AU. There is a geometrically flat inner disk running from 0.3 AU up to 30 AU; an optically thin halo-like component of dust in the inner disk regions; and a massive self-shadowed outer disk running from 130 AU up to 200 AU. We derived a total dust mass in small grains of 10^-3 M0 and a vertical height of the inner wall of the outer disk of h = 60 AU. ....