Radiative Transfer Modeling of a Shadowed Protoplanetary Disk assisted by a Neural Network

Jonathan P. Williams, Myriam Benisty, Christian Ginski, Giuseppe Lodato, Maria Vincent

Published: 2025/9/2

Abstract

We present observations and detailed modeling of a protoplanetary disk around the T Tauri star, V1098 Sco. Millimeter wavelength data from the Atacama Large Millimeter Array (ALMA) show a ring of large dust grains with a central cavity that is filled with molecular gas. Near-infrared data with the Very Large Telescope (VLT) detect the scattered starlight from the disk surface and reveal a large shadow that extends over it's entire southern half. We model the ALMA continuum and line data to determine the outer disk geometry and the central stellar mass. Using radiative transfer models, we demonstrate that a misaligned inner disk, tilted in both inclination and position angle with respect to the outer disk, can reproduce the salient scattered light features seen with the VLT. Applying an image threshold algorithm to compare disk morphologies and training a neural network on a set of high signal-to-noise models, we forward model the data and determine the inner disk geometry. We find that the rotation axes of the inner and outer disks are misaligned by 38 degrees and constrain the mass and location of a perturbing planetary or substellar companion. The technique of simulation based inference that is illustrated here is broadly applicable for radiative transfer modeling of other objects.