Vertical structure of protoplanetary disks

A structure extraction and ellipse fitting (SEEF) algorithm, is implemented using edge detection and Gaussian fitting to locate the structure within protoplanetary disks. Fitting ellipses to the structure reveals spatial offsets from the centre of the ellipse and the star, interpreted as vertical height assuming circular ring geometry. Disk inclination, position angle (PA), and aspect ratio (h_tau_=1/r) are also derived.

The SEEF algorithm obtained successful vertical height measurements for 92 unique disks, revealing variations in height profiles consistent with flared disk geometries. Analysis of the full sample shows that the vertical height profile cannot be confidently described by a single power-law relation. Subdivision of the sample by disk morphology revealed no strong correlations within most categories, with the exception of extended disks (r_outer_>=150au), which exhibited a strong correlation with a single power-law trend.

Investigation into underlying disk properties revealed no correlation for its affect to the vertical height structure. This work presents a consistent methodology for measuring the vertical structure of circumstellar disks using ellipse fitting on scattered light images. While trends in height structure remain weakly correlated for the full sample and many disk morphologies, extended disks (r_outer_>=150au) stand out as the only subgroup showing a clear power-law flaring trend.

The lack of a strong correlation across other morphologies and with system properties like stellar or dust mass suggests that either differing disk morphologies exhibit different vertical height profiles or that another, unidentified factor is influencing the disk flaring.