The Library
Spin–orbit alignment of the β pictoris planetary system
Tools
Tools
Tools
Kraus, Stefan, Le Bouquin, Jean-Baptiste, Kreplin, Alexander, Davies, Claire L., Hone, Edward, Monnier, John D., Gardner, Tyler, Kennedy, Grant M. and Hinkley, Sasha (2020) Spin–orbit alignment of the β pictoris planetary system. The Astrophysical Journal Letters, 897 (1). L8. doi:10.3847/2041-8213/ab9d27
|
PDF
WRAP-Spin–orbit-alignment-β-pictoris-planetary-system-Grant-2020.pdf - Accepted Version - Requires a PDF viewer. Available under License Creative Commons Attribution Non-commercial No Derivatives. Download (2623Kb) | Preview |
Official URL: http://dx.doi.org/10.3847/2041-8213/ab9d27
Abstract
A crucial diagnostic that can tell us about processes involved in the formation and dynamical evolution of planetary systems is the angle between the rotation axis of a star and a planet's orbital angular momentum vector ("spin-orbit" alignment or "obliquity"). Here we present the first spin-orbit alignment measurement for a wide-separation exoplanetary system, namely on the directly imaged planet β Pictoris b. We use VLTI/GRAVITY spectro-interferometry with an astrometric accuracy of 1 μas (microarcsecond) in the Brγ photospheric absorption line to measure the photocenter displacement associated with the stellar rotation. Taking inclination constraints from astroseismology into account, we constrain the three-dimensional orientation of the stellar spin axis and find that β Pic b orbits its host star on a prograde orbit. The angular momentum vectors of the stellar photosphere, the planet, and the outer debris disk are well aligned with mutual inclinations ≤3° ± 5°, which indicates that β Pic b formed in a system without significant primordial misalignments. Our results demonstrate the potential of infrared interferometry to measure the spin-orbit alignment for wide-separation planetary systems, probing a highly complementary regime to the parameter space accessible with the Rossiter-McLaughlin effect. If the low obliquity is confirmed by measurements on a larger sample of wide-separation planets, it would lend support to theories that explain the obliquity in Hot Jupiter systems with dynamical scattering and the Kozai-Lidov mechanism.
| Item Type: | Journal Article | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Subjects: | Q Science > QB Astronomy | |||||||||||||||
| Divisions: | Faculty of Science > Physics | |||||||||||||||
| Library of Congress Subject Headings (LCSH): | Stars -- Rotation, Planetary systems , Planets -- Orbits, Astroseismology | |||||||||||||||
| Journal or Publication Title: | The Astrophysical Journal Letters | |||||||||||||||
| Publisher: | Institute of Physics Publishing, Inc. | |||||||||||||||
| ISSN: | 2041-8205 | |||||||||||||||
| Official Date: | 29 June 2020 | |||||||||||||||
| Dates: |
|
|||||||||||||||
| Volume: | 897 | |||||||||||||||
| Number: | 1 | |||||||||||||||
| Article Number: | L8 | |||||||||||||||
| DOI: | 10.3847/2041-8213/ab9d27 | |||||||||||||||
| Status: | Peer Reviewed | |||||||||||||||
| Publication Status: | Published | |||||||||||||||
| Publisher Statement: | "This is an author-created, un-copyedited version of an article accepted for publication/published in The Astrophysical Journal Letters. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The Version of Record is available online at http://dx.doi.org/10.3847/2041-8213/ab9d27 ” | |||||||||||||||
| Access rights to Published version: | Restricted or Subscription Access | |||||||||||||||
| RIOXX Funder/Project Grant: |
|
|||||||||||||||
| Open Access Version: |
Request changes or add full text files to a record
Repository staff actions (login required)
 |
View Item |
Downloads
Downloads per month over past year
