Has the dust clump in the debris disk of Beta Pictoris moved?

Abstract

The edge-on debris disk of the nearby young star Beta Pictoris shows an unusual brightness asymmetry in the form of a clump. The clump has been detected in both the mid-IR and CO and its origin has so far remained uncertain. Here we present new mid-IR observations of Beta Pic to track any motion of the dust clump. Together with previous observations, the data span a period of 12 years. We measured any projected displacement of the dust clump over the 12-yr period to be $0.2_{-1.4}^{+1.3}$ au away from the star based on the median and 1$\sigma$ uncertainty, and constrain this displacement to be <11 au at the 3$\sigma$ level. This implies that the observed motion is incompatible with Keplerian motion at the 2.8$\sigma$ level. It has been posited that a planet migrating outwards may trap planetesimals into a 2:1 resonance, resulting in the observed clump at pericentre of their orbits that trails the planet. The observed motion is also incompatible with such resonant motion at the 2.6$\sigma$ level. While Keplerian motion and resonant motion is still possible, the data suggest that the dust clump is more likely stationary. Such a stationary dust clump could originate from the collision or tidal disruption of a planet-sized body, or from secular perturbations due to a planet that create regions with enhanced densities in the disk.

14 pages, 8 figures, 5 tables. Published in MNRAS

References in corpus (18)

• The NumPy array: a structure for efficient numerical computation
• Molecular Gas Clumps from the Destruction of Icy Bodies in the $\beta$ Pictoris Debris Disk
• HST/ACS Multiband Coronagraphic Imaging of the Debris Disk around Beta Pictoris
• Debris from giant impacts between planetary embryos at large orbital radii
• Exocometary gas structure, origin and physical properties around $\beta$ Pictoris through ALMA CO multi-transition observations
• A Complete ALMA Map of the Fomalhaut Debris Disk
• Kuiper Belt-Like Hot and Cold Populations of Planetesimal Inclinations in the $\beta$ Pictoris Belt Revealed by ALMA
• Collisional dust avalanches in debris discs
• Planetesimal driven migration as an explanation for observations of high levels of warm, exozodiacal dust
• Solution to the debris disc mass problem: planetesimals are born small?
• The Inner Disk Structure, Disk-Planet Interactions, and Temporal Evolution in the Beta Pictoris System: A Two-Epoch HST/STIS Coronagraphic Study
• On the observability of resonant structures in planetesimal disks due to planetary migration
• Direct imaging of sub-Jupiter mass exoplanets with James Webb Space Telescope coronagraphy
• Planet-Disk Interactions
• Very deep images of the innermost regions of the beta Pictoris debris disc at Lp
• Dust Populations in the Iconic Vega Planetary System Resolved by ALMA
• Detecting a rotation in the epsilon Eridani debris disc
• Planetary Migration to Large Radii

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• The beta Pictoris system: Setting constraints on the planet and the disk structures at mid-IR wavelengths with NEAR
• The ALMA survey to Resolve exoKuiper belt Substructures (ARKS): VI. Asymmetries and offsets
• Dynamics of the Beta Pictoris planetary system and possibility of an additional planet
• Large Interferometer For Exoplanets (LIFE). XIV. Finding terrestrial protoplanets in the galactic neighborhood
• The ALMA survey to Resolve exoKuiper belt Substructures (ARKS) VIII: A dust arc and non-Keplerian gas kinematics in HD 121617
• Direct Imaging Discovery of Giant Exoplanet $\beta$ Pictoris d: A Decade-Long Game of Hide-and-Seek