beta Pic b position relative to the Debris Disk

TL;DR

This study precisely measures the position of beta Pic b relative to its debris disk, revealing that the planet is likely situated in an inclined disk component rather than the main disk, which has implications for understanding the system's dynamics.

Contribution

The paper introduces a high-resolution imaging method to accurately determine the planet's position relative to the debris disk, correcting for systematic errors in previous measurements.

Findings

Beta Pic b is above the midplane of the main disk.

The planet is likely located in the inclined disk component.

The method improves positional measurement accuracy.

Abstract

Context. We detected in 2009 a giant, close-by planet orbiting {\beta} Pic, a young star surrounded with a disk, extensively studied for more than 20 years. We showed that if located on an inclined orbit, the planet could explain several peculiarities of {\beta} Pictoris system. However, the available data did not permit to measure the inclination of {\beta} Pic b with respect to the disk, and in particular to establish in which component of the disk - the main, extended disk or the inner inclined component/disk-, the planet was located. Comparison between the observed planet position and the disk orientation measured on previous imaging data was not an option because of potential biases in the measurements. Aims. Our aim is to measure precisely the planet location with respect to the dust disk using a single high resolution image, and correcting for systematics or errors that degrades the precision of the disk and planet relative position measurements. Methods. We gathered new NaCo data at Ks band, with a set-up optimized to derive simultaneously the orientation(s) of the disk(s) and that of the planet. Results. We show that the projected position of {\beta} Pic b is above the midplane of the main disk. With the current data and knowledge on the system, this implies that {\beta} Pic b cannot be located in the main disk. The data rather suggest the planet being located in the inclined component.