Shadows cast by a warp in the HD 142527 protoplanetary disk

TL;DR

This paper uses high-contrast imaging and radiative transfer modeling to analyze shadows cast by the inner disk of HD 142527, revealing a 70-degree inclination between the inner and outer disks and providing insights into the system's 3D structure.

Contribution

It demonstrates that the observed shadows are caused by the inner disk, allowing the determination of the three-dimensional disk geometry through radiative transfer modeling.

Findings

Inner and outer disks are inclined by 70+-5 degrees.

Shadows reveal the 3D structure of the disk system.

Implications for gas dynamics and physical conditions in shadowed regions.

Abstract

Detailed observations of gaps in protoplanetary disks have revealed structures that drive current research on circumstellar disks. One such feature is the two intensity nulls seen along the outer disk of the HD 142527 system, which are particularly well traced in polarized differential imaging. Here we propose that these are shadows cast by the inner disk. The inner and outer disk are thick, in terms of the unit-opacity surface in H-band, so that the shape and orientation of the shadows inform on the three-dimmensional structure of the system. Radiative transfer predictions on a parametric disk model allow us to conclude that the relative inclination between the inner and outer disks is 70+-5 deg. This finding taps the potential of high-contrast imaging of circumstellar disks, and bears consequences on the gas dynamics of gapped disks, as well as on the physical conditions in the shadowed regions.