A Detailed Characterization of HR 8799's Debris Disk with ALMA in Band 7

Journal Article · Tue Jun 01 04:00:00 EDT 2021 · Astronomical Journal (New York, N.Y. Online)

DOI:https://doi.org/10.3847/1538-3881/ABF4E0· OSTI ID:23159249

Faramaz, Virginie; Mamajek, Eric E.; Bryden, Geoffrey; Stapelfeldt, Karl R. ^[1]; Marino, Sebastian ^[2]; Booth, Mark ^[3]; Matrà, Luca ^[4]; Casassus, Simon ^[5]; Cuadra, Jorge ^[6]; Hales, Antonio S. ^[7]; Zurlo, Alice ^[8]

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1. Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena CA 91109 (United States)
2. Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom)
3. Astrophysikalisches Institut und Universitätssternwarte, Friedrich-Schiller-Universität Jena, Schillergäßchen 2-3, D-07745 Jena (Germany)
4. Centre for Astronomy, School of Physics, National University of Ireland Galway, University Road, Galway (Ireland)
5. Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Santiago (Chile)
6. Departamento de Ciencias, Facultad de Artes Liberales, Universidad Adolfo Ibáñez, Av. Padre Hurtado 750, Viña del Mar (Chile)
7. Joint ALMA Observatory, Alonso de Córdova 3107, Vitacura 763-0355, Santiago (Chile)
8. Núcleo de Astronomía, Facultad de Ingeniería y Ciencias, Universidad Diego Portales, Av. Ejercito 441, Santiago (Chile)

The exoplanetary system of HR 8799 is one of the rare systems in which multiple planets have been directly imaged. Its architecture is strikingly similar to that of the solar system, with the four imaged giant planets surrounding a warm dust belt analogous to the Asteroid Belt, and themselves being surrounded by a cold dust belt analog to the Kuiper Belt. Previous observations of this cold belt with ALMA in Band 6 (1.3 mm) revealed its inner edge, but analyses of the data differ on its precise location. It was therefore unclear whether or not the outermost planet HR 8799 b was dynamically sculpting it. We present here new ALMA observations of this debris disk in Band 7 (340 GHz, 880 μm). These are the most detailed observations of this disk obtained so far, with a resolution of 1″ (40 au) and sensitivity of 9.8 μJy beam{sup −1}, which allowed us to recover the disk structure with high confidence. In order to constrain the disk morphology, we fit its emission using radiative transfer models combined with a Markov Chain Monte Carlo procedure. We find that this disk cannot be adequately represented by a single power law with sharp edges. It exhibits a smoothly rising inner edge and smoothly falling outer edge, with a peak in between, as expected from a disk that contains a high-eccentricity component, hence confirming previous findings. Whether this excited population and inner edge shape stem from the presence of an additional planet remains, however, an open question.

• OSTI ID: 23159249
• Journal Information: Astronomical Journal (New York, N.Y. Online), Journal Name: Astronomical Journal (New York, N.Y. Online) Journal Issue: 6 Vol. 161; ISSN 1538-3881
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
79 ASTRONOMY AND ASTROPHYSICS
ASTEROIDS
GHZ RANGE
MARKOV PROCESS
MONTE CARLO METHOD
MORPHOLOGY
PLANETS
RADIANT HEAT TRANSFER
RESOLUTION
SENSITIVITY
SOLAR SYSTEM