Limits on the presence of planets in systems with debris disks: HD 92945 and HD 107146

TL;DR

This study uses high-contrast imaging and astrometry to constrain the presence and properties of potential planets in debris disk systems HD 92945 and HD 107146, limiting their masses and separations.

Contribution

It provides new upper limits on planet masses and locations within debris disks by combining direct imaging with astrometric and radial velocity data.

Findings

Excluded some planetary configurations based on imaging limits.

Constrained potential planet masses to 1-2 M Jup inside the gaps.

Limited the mass and separation of companions causing proper motion anomalies.

Abstract

Recent observations of resolved cold debris disks at tens of au have revealed that gaps could be a common feature in these Kuiper belt analogues. Such gaps could be evidence for the presence of planets within the gaps or closer-in near the edges of the disk. We present SPHERE observations of HD 92945 and HD 107146, two systems with detected gaps. We constrained the mass of possible companions responsible for the gap to 1-2 M Jup for planets located inside the gap and to less than 5 M Jup for separations down to 20 au from the host star. These limits allow us to exclude some of the possible configurations of the planetary systems proposed to explain the shape of the disks around these two stars. In order to put tighter limits on the mass at very short separations from the star, where direct imaging data are less effective, we also combined our data with astrometric measurements from Hipparcos and Gaia and radial velocity measurements. We were able to limit the separation and the mass of the companion potentially responsible for the proper motion anomaly of HD 107146 to values of 2-7 au and 2-5 M Jup , respectively.