Resolving the FU Ori System with ALMA: Interacting Twin Disks?

Abstract

FU Orionis objects are low-mass pre-main sequence stars characterized by dramatic outbursts of several magnitudes in brightness. These outbursts are linked to episodic accretion events in which stars gain a significant portion of their mass. The physical processes behind these accretion events are not yet well understood. The archetypical FU Ori system, FU Orionis, is composed of two young stars with detected gas and dust emission. The continuum emitting regions have not been resolved until now. Here, we present 1.3 mm observations of the FU Ori binary system with ALMA. The disks are resolved at 40 mas resolution. Radiative transfer modeling shows that the emission from FU Ori north (primary) is consistent with a dust disk with a characteristic radius of $\sim$11 au. The ratio between major and minor axes shows that the inclination of the disk is $\sim$37 deg. FU Ori south is consistent with a dust disk of similar inclination and size. Assuming the binary orbit shares the same inclination angle as the disks, the deprojected distance between north and south components is 0.6'', i.e. $\sim$250 au. Maps of ${}^{12}$CO emission show a complex kinematic environment with signatures disk rotation at the location of the northern component, and also (to a lesser extent) for FU Ori south. The revised disk geometry allows us to update FU Ori accretion models (Zhu et al.), yielding a stellar mass and mass accretion rate of FU Ori north of 0.6 M${}_{\odot }$ and 3.8$\times 10^{-5}$ M${}_{\odot }$ yr${}^{-1}$, respectively.

arXiv comment9 pages, 4 figures, accepted for publication in ApJ

References in corpus (37)

• Astropy: A Community Python Package for Astronomy
• emcee: The MCMC Hammer
• Gaia Data Release 2. Summary of the contents and survey properties
• The Spitzer c2d Legacy Results: Star Formation Rates and Efficiencies; Evolution and Lifetimes
• The distance to the Orion Nebula
• Protoplanetary Disk Structures in Ophiuchus II: Extension to Fainter Sources
• Episodic accretion in magnetically layered protoplanetary discs
• The burst mode of accretion and disk fragmentation in the early embedded stages of star formation
• Imaging the water-snow line during a protostellar outburst
• 2-D simulations of FU Orionis disk outbursts
• The Hot Inner Disk of FU Ori
• Long-term Evolution of Protostellar and Protoplanetary Disks. I. Outbursts
• Flybys in protoplanetary discs: I. Gas and dust dynamics
• Accretion Outbursts in Self-gravitating Protoplanetary Disks
• ALMA observations of the $\eta$ Corvi debris disc: inward scattering of CO-rich exocomets by a chain of 3-30 M${}_{\oplus }$ planets?
• The Gravo-Magneto Limit Cycle in Accretion Disks
• Circumstellar Disks of the Most Vigorously Accreting Young Stars
• Cloudlet capture by Transitional Disk and FU Orionis stars
• The photometric evolution of FU Orionis objects: disc instability and wind-envelope interaction
• The VLA Nascent Disk and Multiplicity Survey of Perseus Protostars (VANDAM). V. 18 Candidate Disks around Class 0 and I Protostars in the Perseus Molecular Cloud
• Flybys in protoplanetary discs: II. Observational signatures
• The ALMA early science view of FUor/EXor objects - V: continuum disc masses and sizes
• Disk Masses for Embedded Class I Protostars in the Taurus Molecular Cloud
• Near-Infrared High-Resolution Imaging Polarimetry of FU Ori-Type Objects: Towards A Unified Scheme for Low-Mass Protostellar Evolution
• The Differential Rotation of FU Ori
• Encounter-driven accretion in young stellar clusters - A connection to FUors?
• The ALMA Early Science view of FUor/EXor objects. I. Through the looking-glass of V2775 Ori
• Stellar orbit evolution in close circumstellar disc encounters
• The ALMA Early Science View of FUor/EXor objects. II. The Very Wide Outflow Driven by HBC 494
• A concordant scenario to explain FU Ori from deep centimeter and millimeter interferometric observations
• The Early ALMA View of the FU Ori Outburst System
• The ALMA Early Science View of FUor/EXor objects. III. The Slow and Wide Outflow of V883 Ori
• Diagnosing 0.1-10 au scale morphology of the FU\,Ori disk using ALMA and VLTI/GRAVITY
• The ALMA Early Science View of FUor/EXor objects. IV. Misaligned Outflows in the Complex Star-forming Environment of V1647 Ori and McNeil's Nebula
• Constraining mass ratio and extinction in the FU Orionis binary system with infrared integral field spectroscopy
• The Circumstellar Disk and Asymmetric outflow of the EX Lup Outburst System
• Science with an ngVLA: New Frontiers in Protostellar Multiplicity with the ngVLA

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• Diagnosing FUor-like Sources: The Parameter Space of Viscously Heated Disks in the Optical and Near-IR
• On the rise times in FU Orionis events
• Millimeter-sized Dust Grains Appear Surviving the Water-sublimating Temperature in the Inner 10 au of the FU Ori Disk
• Sustained FU Orionis-type outbursts from colliding discs in stellar flybys
• A massive Keplerian protostellar disk with flyby-induced spirals in the Central Molecular Zone
• Application of a Steady-State Accretion Disk Model to Spectrophotometry and High-Resolution Spectra of Two Recent FU Ori Outbursts
• Viscous Heating and Boundary Layer Accretion in the Disk of Outbursting Star FU Orionis
• Close stellar flybys common in low-mass clusters
• The SPHERE view of three interacting twin disc systems in polarised light
• Chemical signatures of a warped protoplanetary disc
• Extreme evaporation of planets in hot thermally unstable protoplanetary discs: the case of FU Ori
• The disk of FU Orionis viewed with MATISSE/VLTI: first interferometric observations in $L$ and $M$ bands
• Spatially correlated stellar accretion in the Lupus star forming region: Evidence for ongoing infall from the interstellar medium
• Photometric and spectroscopic study of the EXor-like eruptive young star Gaia19fct
• ALMA Observations of Young Eruptive Stars: continuum disk sizes and molecular outflows
• Spirals and clumps in V960 Mon: signs of planet formation via gravitational instability around an FU Ori star?
• A Tale of Two Transition Disks: ALMA long-baseline observations of ISO-Oph 2 reveal two closely packed non-axisymmetric rings and a $\sim$2 au cavity
• An APEX study of molecular outflows in FUor-type stars
• FU Orionis disk outburst: evidence for a gravitational instability scenario triggered in a magnetically dead zone
• Resolving the Binary Components of the Outbursting Protostar HBC 494 with ALMA
• Imaging the warped dusty disk wind environment of SU Aurigae with MIRC-X
• Accretion bursts in young intermediate-mass stars make planet formation challenging
• Protostellar Outflows: a window to the past
• Time-dependent response of protoplanetary disk temperature to an FU Ori-type luminosity outburst
• One of Everything: The Breakthrough Listen Exotica Catalog
• Warps survive beyond fly-by encounters in protoplanetary disks. RW Aur A as a case study
• Episodic accretion in high-mass star formation: An analysis of thermal instability for axially symmetric disks
• Simulation of a protoplanetary disk accretion activity due to a collision with a gas stream
• Characterizing and spectrally modeling embedded FUor eruptions in the near-infrared