Constraining the Movement of the Spiral Features and the Locations of Planetary Bodies within the AB Aur System

TL;DR

This study models the AB Aur system using radiative transfer to understand its disk structure and spiral features, finding no significant movement of spirals over 5.8 years, which constrains potential planetary perturbers' locations.

Contribution

It provides the first multi-epoch analysis of spiral motion in AB Aur, constraining the location of potential planets influencing the disk structures.

Findings

Disk-dominated model fits the SED and imagery.

No significant spiral rotation detected over 5.8 years.

Planetary perturbers likely located beyond 47 AU.

Abstract

We present new analysis of multi-epoch, H-band, scattered light images of the AB Aur system. We used a Monte Carlo, radiative transfer code to simultaneously model the system's SED and H-band polarized intensity imagery. We find that a disk-dominated model, as opposed to one that is envelope dominated, can plausibly reproduce AB Aur's SED and near-IR imagery. This is consistent with previous modeling attempts presented in the literature and supports the idea that at least a subset of AB Aur's spirals originate within the disk. In light of this, we also analyzed the movement of spiral structures in multi-epoch H-band total light and polarized intensity imagery of the disk. We detect no significant rotation or change in spatial location of the spiral structures in these data, which span a 5.8 year baseline. If such structures are caused by disk-planet interactions, the lack of observed rotation constrains the location of the orbit of planetary perturbers to be >47 AU.