The Mineralogy and Structure of the Inner Debris Disk of β Pictoris

Abstract

We observed the edge-on, planet-bearing disk of β Pictoris using T-ReCS at Gemini to clarify and extend previous observations and conclusions about this unique system. Our spectroscopy and spectral modeling of the 10-micron silicate feature constrain the spatial distributions of three representative dust components (0.1-micron/2.0-micron glassy olivine and crystalline forsterite) across the inner 20-AU of the disk. We confirm that the 2.0-micron glassy olivine is strongly peaked in the disk center and that the 0.1-micron glassy olivine does not show this concentration, but rather is double peaked, with the peaks on either side of the star. However, we do not see the strong difference in brightness between those two peaks reported in a previous study. Although the spatial distribution of the 0.1-micron dust is consistent with the scenario of a dust-replenishing planetesimal belt embedded in the disk, we note an alternative interpretation that can explain the spatial distributions of the 0.1-micron and 2.0-micron grains simultaneously and does not require the planetesimal belt. In addition to the spectroscopy, we also obtained a new 11.7 micron image of the β Pic disk. By comparing this image with that acquired in 2003, we confirm the existence and overall shape of the dusty clump at 52 AU in the SW disk. We speculate that the clump's projected spatial displacement of ~2.0 AU, a 3.6-σ result, between two epochs separated by seven years is due to the Keplerian motion of the clump at an orbital radius of $54.3_{-1.2}^{+2.0}$ AU.

9 pages, 8 figures, to be published in ApJ

References in corpus (8)

• HST/ACS Multiband Coronagraphic Imaging of the Debris Disk around Beta Pictoris
• Orbital characterization of the βPictoris b giant planet
• beta Pic b position relative to the Debris Disk
• Collisional dust avalanches in debris discs
• Spitzer Infrared Spectrograph survey of young stars in the Chamaeleon I star-forming region
• The Dust and Gas Around beta Pictoris
• Destruction of massive fragments in protostellar disks and crystalline silicate production
• VLT/NACO coronagraphic observations of fine structures in the disk of beta Pictoris

Cited by in corpus (15)

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• Debris from giant impacts between planetary embryos at large orbital radii
• The Inner Disk Structure, Disk-Planet Interactions, and Temporal Evolution in the Beta Pictoris System: A Two-Epoch HST/STIS Coronagraphic Study
• ALMA resolves CI emission from the $\beta$ Pictoris debris disk
• A SMACK Model of Colliding Planetesimals in the $\beta$ Pictoris Debris Disk
• Insights into planet formation from debris disks: II. Giant impacts in extrasolar planetary systems
• A Comprehensive Dust Model Applied to the Resolved Beta Pictoris Debris Disk from Optical to Radio Wavelengths
• Probing the Terrestrial Regions of Planetary Systems: Warm Debris Disks with Emission Features
• Dust from collisions: A way to probe the composition of exo-planets?
• Giant Impacts and Debris Disk Morphology
• Has the dust clump in the debris disk of Beta Pictoris moved?
• Polarization from Aligned Dust Grains in the $\beta$ Pic Debris Disk
• The beta Pictoris system: Setting constraints on the planet and the disk structures at mid-IR wavelengths with NEAR
• Debris Disks: Probing Planet Formation
• The ALMA survey to Resolve exoKuiper belt Substructures (ARKS) VIII: A dust arc and non-Keplerian gas kinematics in HD 121617