Widespread atomic gas emission reveals the rotation of the beta Pictoris disk

Abstract

We present high resolution Na I D spectroscopy of the beta Pic disk, and the resonantly scattered sodium emission can be traced from less than 30 AU to at least 140 AU from the central star. This atomic gas is co-existent with the dust particles, suggestive of a common origin or source. The disk rotates towards us in the south-west and away from us in the north-east. The velocity pattern of the gas finally provides direct evidence that the faint linear feature seen in images of the star is a circumstellar disk in Keplerian rotation. From modelling the spatial distribution of the Na I line profiles we determine the effective dynamical mass to be 1.40 +/- 0.05 M_sun, which is smaller than the stellar mass, 1.75 M_sun. We ascribe this difference to the gravity opposing radiation pressure in the Na I lines. We argue that this is consistent with the fact that Na is nearly completely ionised throughout the disk (Na I/Na < 10^-4). The total column density of sodium gas is N(Na) = 10^15 cm^-2.

9 pages, including 6 figs (fig.1 in colour). Accepted by ApJL

References in corpus (1)

• Dynamical modeling of large scale asymmetries in the beta Pictoris dust disk

Cited by in corpus (46)

• A giant planet imaged in the disk of the young star Beta Pictoris
• Rosseland and Planck Mean Opacities for Protoplanetary Discs
• Debris Disks: Structure, Composition, and Variability
• Debris Disks: Seeing Dust, Thinking of Planetesimals and Planets
• Orbital characterization of the βPictoris b giant planet
• The Carbon-Rich Gas in the Beta Pictoris Circumstellar Disk
• Predictions for the secondary CO, C and O gas content of debris discs from the destruction of volatile-rich planetesimals
• Formation of sharp eccentric rings in debris disks with gas but without planets
• Debris from giant impacts between planetary embryos at large orbital radii
• GASPS - a Herschel survey of gas and dust in Protoplanetary Disks: Summary and Initial Statistics
• Exocometary gas structure, origin and physical properties around $\beta$ Pictoris through ALMA CO multi-transition observations
• beta Pic b position relative to the Debris Disk
• A self-consistent model for the evolution of the gas produced in the debris disc of $\beta$ Pictoris
• The Spatial Structure of the beta Pictoris Gas Disk
• Braking the Gas in the beta Pictoris Disk
• Gas and dust in the Beta Pictoris Moving Group as seen by the Herschel Space Observatory
• Disk Dispersal: Theoretical Understanding and Observational Constraints
• Looking for Pure Rotational H_2 Emission from Protoplanetary Disks
• Formation of Narrow Dust Rings in Circumstellar Debris Disks
• Herschel HIFI observations of ionised carbon in the β Pictoris debris disk
• ALMA Detection of Extended Millimeter Halos in the HD 32297 and HD 61005 Debris Disks
• ALMA resolves CI emission from the $\beta$ Pictoris debris disk
• Exposing the Gas Braking Mechanism of the beta Pictoris Disk
• Herschel detects oxygen in the beta Pictoris debris disk
• Ro-vibrational CO Detected in the $\beta$~Pictoris Circumstellar Disk
• The magnetorotational instability in debris-disc gas
• The co-existence of hot and cold gas in debris discs
• Fomalhaut b as a Cloud of Dust: Testing Aspects of Planet Formation Theory
• A Ring of Warm Dust in the HD 32297 Debris Disk
• Can gas in young debris disks be constrained by their radial brightness profiles?
• Line emission from circumstellar disks around A stars
• The 1.2 Millimeter Image of the beta Pictoris Disk
• Gas emission from debris disks around A and F stars
• The Mineralogy and Structure of the Inner Debris Disk of β Pictoris
• On the unusual gas composition in the Beta Pictoris debris disk
• VLT imaging of the β Pictoris gas disk
• The orbit of Beta Pic b as a transiting planet
• The far reaches of the beta Pictoris debris disk
• Is Beta Pic b the transiting planet of November 1981?
• Polarization from Aligned Dust Grains in the $\beta$ Pic Debris Disk
• High latitude gas in the Beta Pictoris system. A possible origin related to Falling Evaporating Bodies
• Circumstellar discs: What will be next?
• Constraints on the gas content of the Fomalhaut debris belt. Can gas-dust interactions explain the belt's morphology?
• Polarimetric coronagraphy of BD+31643
• Transit distances and composition of low-velocity exocomets in the $\beta$ Pic system
• Constraining the orbit of the possible companion to Beta Pictoris: New deep imaging observations