A Detailed View of the Circumstellar Environment and Disk of the Forming O-star AFGL 4176

Abstract

We present a detailed analysis of the disk and circumstellar environment of the forming O-type star AFGL 4176 mm1, placing results from the Atacama Large Millimeter/submillimeter Array (ALMA) into context with multiwavelength data. With ALMA, we detect seventeen 1.2 mm continuum sources within 5${}^{\prime \prime }$ (21,000 au) of AFGL 4176 mm1. We find that mm1 has a spectral index of 3.4$\pm$0.2 across the ALMA band, with $>$87% of its 1.2 mm continuum emission from dust. The source mm2, projected 4200 au from mm1, may be a companion or a blueshifted knot in a jet. We also explore the morphological differences between the molecular lines detected with ALMA, finding 203 lines from 25 molecules, which we categorize into several morphological types. Our results show that AFGL 4176 mm1 provides an example of a forming O-star with a large and chemically complex disk, which is mainly traced by nitrogen-bearing molecules. Lines that show strong emission on the blueshifted side of the disk are predominantly oxygen-bearing, which we suggest are tracing a disk accretion shock. The molecules C${}^{34}$S, H${}_2$CS and CH${}_3$CCN trace a slow wide-angle wind or dense structures in the outflow cavity walls. With the Australia Telescope Compact Array (ATCA), we detect a compact continuum source ($<$2000 $\times$ 760 au) at 1.2 cm, associated with mm1, of which $>$96% is from ionized gas. The ATCA NH${}_3$(1,1) and (2,2) emission traces a large-scale (r$\sim$0.5 pc) rotating toroid with the disk source mm1 in the blueshifted part of this structure offset to the northwest.

arXiv commentAccepted for publication in The Astrophysical Journal, 50 pages, 26 figures. Data available online at http://doi.org/10.5281/zenodo.3369188

References in corpus (104)

• Astropy: A Community Python Package for Astronomy
• Binary companions of evolved stars in APOGEE DR14: Search method and catalog of ~5,000 companions
• Embedded Clusters in Molecular Clouds
• Interstellar Dust Grains
• Estimating distances from parallaxes IV: Distances to 1.33 billion stars in Gaia Data Release 2
• Protoplanetary Disks and Their Evolution
• The Disk Substructures at High Angular Resolution Project (DSHARP): I. Motivation, Sample, Calibration, and Overview
• The Formation of Massive Stars from Turbulent Cores
• Complex Chemistry in Star-Forming Regions: An Expanded Gas-Grain Warm-up Chemical Model
• Scattering by Interstellar Dust Grains: Optical and Ultraviolet
• ALMA Survey of Lupus Protoplanetary Disks I: Dust and Gas Masses
• Southern Massive Stars at High Angular Resolution: Observational Campaign and Companion Detection
• The hierarchical formation of a stellar cluster
• The ALMA Protostellar Interferometric Line Survey (PILS): First results from an unbiased submillimeter wavelength line survey of the Class 0 protostellar binary IRAS 16293-2422 with ALMA
• ALMA Survey of Lupus Protoplanetary Disks II: Gas Disk Radii
• On the diversity and statistical properties of protostellar discs
• A 0.2 solar mass protostar with a Keplerian disk in the very young L1527 IRS system
• Circumventing the radiation pressure barrier in the formation of massive stars via disk accretion
• PROSAC: A Submillimeter Array survey of low-mass protostars. II. The mass evolution of envelopes, disks, and stars from the Class 0 through I stages
• The Origin of Massive O-type Field Stars. Part II: Field O stars as runaways
• HYPERION: An open-source parallelized three-dimensional dust continuum radiative transfer code
• A Keplerian disk around a Class 0 source: ALMA observations of VLA1623A
• An Ammonia Spectral Atlas of Dense Cores in Perseus
• A Millimeter Continuum Size-Luminosity Relationship for Protoplanetary Disks
• A disk of dust and molecular gas around a high-mass protostar
• Accretion disks in luminous young stellar objects
• The RMS Survey: Critical Tests of Accretion Models for the Formation of Massive Stars
• A hot compact dust disk around a massive young stellar object
• ATLASGAL --- properties of compact HII regions and their natal clumps
• Infalling-Rotating Motion and Associated Chemical Change in the Envelope of IRAS 16293-2422 Source A Studied with ALMA
• Chemical evolution in the early phases of massive star formation. I
• Protoplanetary Disk Properties in the Orion Nebula Cluster: Initial Results from Deep, High-Resolution ALMA Observations
• A Keplerian-like disk around the forming O-type star AFGL 4176
• Search for massive protostar candidates in the southern hemisphere: II. Dust continuum emission
• Rotationally-supported disks around Class I sources in Taurus: disk formation constraints
• ALMA Observations of the Transition from Infall Motion to Keplerian Rotation around the Late-phase Protostar TMC-1A
• First hydrodynamics simulations of radiation forces and photoionization feedback in massive star formation
• G11.92-0.61 MM1: A Keplerian disc around a massive young proto-O star
• The Early Evolution of Massive Stars: Radio Recombination Line Spectra
• Chemical modelling of complex organic molecules with peptide-like bonds in star-forming regions
• ATLASGAL --- Complete compact source catalogue: 280\degr\ $<\ell <$ 60\degr
• The ALMA view of the protostellar system HH212 - The wind, the cavity, and the disk
• Envelope Emission in Young Stellar Systems: A Sub-Arcsecond Survey of Circumstellar Structure
• A Sub-arcsecond Survey Toward Class 0 Protostars in Perseus: Searching for Signatures of Protostellar Disks
• G11.92-0.61 MM 1: A fragmented Keplerian disk surrounding a proto-O star
• On the robustness of the ammonia thermometer
• A necklace of dense cores in the high-mass star forming region G35.20-0.74N: ALMA observations
• Disk and Envelope Structure in Class 0 Protostars: II. High Resolution Millimeter Mapping of the Serpens Sample
• CO bandhead emission of massive young stellar objects: determining disc properties
• A Keplerian disk around Orion Source I, a ~15 Msun YSO
• Protostellar Outflows and Radiative Feedback from Massive Stars. II. Feedback, Star Formation Efficiency, and Outflow Broadening
• Accurate water maser positions from HOPS
• Substructures in the Keplerian disc around the O-type (proto)star G17.64+0.16
• No Keplerian Disk >10 AU around the Protostar B335: Magnetic Braking or Young Age?
• The Impact of Feedback During Massive Star Formation by Core Accretion
• Protostellar Outflows and Radiative Feedback from Massive Stars
• The Remarkable Mid-Infrared Jet of Massive Young Stellar Object G35.20-0.74
• Resolving the polarized dust emission of the disk around the massive star powering the HH~80-81 radio jet
• Accelerating infall and rotational spin-up in the hot molecular core G31.41+0.31
• Vertical Structure of the Transition Zone from Infalling Rotating Envelope to Disk in the Class 0 Protostar, IRAS04368+2557
• Thermal Feedback in the high-mass star and cluster forming region W51
• Discovery of a sub-Keplerian disk with jet around a 20Msun young star. ALMA observations of G023.01-00.41
• Subarcsecond Imaging of the NGC 6334 I(N) Protocluster: Two Dozen Compact Sources and a Massive Disk Candidate
• ALMA resolves the hourglass magnetic field in G31.41+0.31
• Kinematics of the inner thousand AU region around the young massive star AFGL 2591-VLA3: a massive disk candidate?
• The VLA Nascent Disk and Multiplicity Survey: First Look at Resolved Candidate Disks around Class 0 and I Protostars in the Perseus Molecular Cloud
• The origin of mid-infrared emission in massive young stellar objects: multi-baseline VLTI observations of W33A
• Chemical segregation toward massive hot cores: The AFGL2591 star forming region
• Kinematics of the Ammonia Disk around the Protostar NGC 1333 IRAS 4A2
• Chemistry of massive young stellar objects with a disk-like structure
• Radiative transfer modelling of W33A MM1: 3-D structure and dynamics of a complex massive star forming region
• Spiral arms and instability within the AFGL 4176 mm1 disc
• History of the solar-type protostar IRAS16293-2422 as told by the cyanopolyynes
• The search for high-mass protostars with ALMA revealed up to kilo-parsec scales (SPARKS): I. Indication for a centrifugal barrier in the environment of a single high-mass envelope
• Core fragmentation and Toomre stability analysis of W3(H2O): A case study of the IRAM NOEMA large program CORE
• The ALMA view of W33A: A Spiral Filament Feeding the Candidate Disc in MM1-Main
• A Pre-Protostellar Core in L1551
• Tracing the cold and warm physico-chemical structure of deeply embedded protostars: IRAS 16293-2422 versus VLA 1623-2417
• Chemical Segregation in Hot Cores With Disk Candidates: An investigation with ALMA
• ALMA Observations of Orion Source I at 350 and 660 GHz
• The Spatial Distribution of Organics toward the High-Mass YSO NGC 7538 IRS9
• An Ordered Envelope-disk Transition in the Massive Protostellar Source G339.88-1.26
• Complex organic molecules in organic-poor massive young stellar objects
• An Asymmetric Keplerian Disk Surrounding the O-type Protostar IRAS16547$-$4247
• Orion Source I's disk is salty
• Physical and chemical structure of planet-forming disks probed by millimeter observations and modeling
• The RMS Survey: Ammonia mapping of the environment of massive young stellar objects
• The Difference in Abundances between N-bearing and O-bearing Species in High-Mass Star-Forming Regions
• Extended emission associated with young HII regions
• A high-mass protobinary system with spatially resolved circumstellar accretion disks and circumbinary disk
• High-mass star formation at sub-50AU scales
• Slow ionized wind and rotating disklike system associated with the high-mass young stellar object G345.4938+01.4677
• Angular momentum loss in the envelope-disk transition region of HH 111 protostellar system: evidence for magnetic braking?
• SiO Outflow Signatures Toward Massive Young Stellar Objects with Linearly Distributed Methanol Masers
• The VLA/ALMA Nascent Disk and Multiplicity (VANDAM) Survey of Orion Protostars I. Identifying and Characterizing the Protostellar Content of the OMC2-FIR4 and OMC2-FIR3 Regions
• Dynamics of a Massive Binary at Birth
• Chemistry of the High-Mass Protostellar Molecular Clump IRAS 16562-3959
• The circumestellar disk of the B0 protostar powering the HH 80-81 radio jet
• Unveiling a cluster of protostellar disks around the massive protostar GGD27 MM1
• Multiplicity and disks within the high-mass core NGC7538IRS1: Resolving cm line and continuum emission at ~0.06"x0.05" resolution
• SMA Observations of the Hot Molecular Core IRAS 18566+0408
• On the massive young stellar object AFGL4176: High-spatial-resolution multi-wavelength observations and modeling
• Resolving the MYSO binaries PDS 27 and PDS 37 with VLTI/PIONIER
• Evolution of HII regions in hierarchically structured molecular clouds

Cited by in corpus (12)

• JWST Observations of Young protoStars (JOYS): overview of program and early results
• Radiation hydrodynamics simulations of protoplanetary disks: Stellar mass dependence of the disk photoevaporation rate
• Digging into the Interior of Hot Cores with ALMA (DIHCA). II. Exploring the Inner Binary (Multiple) System Embedded in G335 MM1 ALMA1
• ALMA observations of the Extended Green Object G19.01$-$0.03: I. A Keplerian disc in a massive protostellar system
• Salt-bearing disk candidates around high-mass young stellar objects
• The first interferometric survey in the K-band of massive YSOs. On the hot dust, ionised gas, and binarity at au scales
• The role of magnetic fields in the formation of multiple massive stars
• Disk fragmentation in high-mass star formation. High-resolution observations towards AFGL 2591-VLA 3
• Evidence for dense gas heated by the explosion in Orion KL
• The physical and chemical structure of high-mass star-forming regions. Unraveling chemical complexity with the NOEMA large program "CORE"
• VLA Observations of 9 Extended Green Objects in the Milky Way: Ubiquitous Weak, Compact Continuum Emission, and Multi-Epoch Emission from CH${}_3$OH, H${}_2$O, and NH${}_3$ Masers
• ALMA detections of circumstellar disks in the giant Hii region M17. Probing the intermediate- to high-mass pre-main-sequence population