Dynamical Mass Constraints on Transition Disk Perturbers with the G23H Catalog

TL;DR

This study uses combined Hipparcos and Gaia data to constrain the masses of potential companions in 11 transition disk systems, identifying several likely sub-stellar objects and setting limits on undetected companions.

Contribution

It introduces a novel method combining astrometry data to dynamically estimate masses of disk perturbers, including detections and non-detections, and assesses data quality impacts.

Findings

Detected companions in 7 systems, including known and new candidates.

Set mass and semi-major axis limits for non-detections.

Identified potential astrometric noise affecting measurements.

Abstract

We present dynamical mass constraints on perturbers in 11 transition disk systems using a novel combination of calibrated Hipparcos and Gaia absolute astrometry data. Out of the sample of 11, we find support for companions in seven systems, with significant detections in three. These systems are: HD 142527, where we clearly detect the known low-mass stellar companion HD 142527 B; AB Aurigae, where we detect a low-mass stellar or sub-stellar companion; and MWC 758, where we detect a likely sub-stellar companion. We also find strong evidence of companions to HD 97048 and UX Tau A, and moderate evidence for companions to HD 100546 and CQ Tau. In the four systems with non-detections, we find no evidence for companions more massive than $\sim$6 $M_{\mathrm{Jup}}$ with a semi-major axis greater than 3 au for HD 100453, nor for companions more massive than $\sim$2 $M_{\mathrm{Jup}}$ with a semi-major axis greater than 2 au for TW Hya. We also find no evidence for stellar mass companions with semi-major axes between $\sim$3 and $\sim$25 au for both HD 34282 and RY Lup. In addition to our fiducial model, we perform cross validation between astrometry sources. By comparing results across models, we find tentative evidence of a short timescale excess astrometric noise that may impact some protoplanetary disk systems. We conclude with predictions for the prospects of making dynamical mass constraints on protoplanets in protoplanetary disk systems with Gaia data release 4 using detailed simulations of Gaia DR4 data of PDS 70 and WISPIT 2.