Water vapor emission at the warm cavity wall of the HD 100546 disk as revealed by ALMA

Abstract

We present spatially resolved ALMA observations of the water line at 183 GHz in the disk around the Herbig star HD 100546. The water vapor emission peaks at the inner edge of the warm dust cavity, located ~15 au from the central star. We attribute this to thermal desorption at the water snowline, shifted outward at the dust cavity wall directly heated by the intense radiation. This represents the first spatially resolved image of the water snowline using ALMA observations of the main water isotopologue in a protoplanetary disk. The water emission morphology peaking inside the first dust ring is consistent with previous ALMA detections of oxygen-bearing complex organic molecules in the disk, including thermally desorbed methanol. These findings signal that warm cavities of transition disks provide ideal targets to directly reconstruct the spatial distribution of water vapor and the snowline location with ALMA, and directly connect water vapor emission to ice desorption of complex organic species.

13 pages, 6 figures

References in corpus (31)

• Array Programming with NumPy
• The Gaia mission
• Gaia Data Release 3: Summary of the content and survey properties
• CASA, the Common Astronomy Software Applications for Radio Astronomy
• Multi-Scale CLEAN deconvolution of radio synthesis images
• The Critical Density and the Effective Excitation Density of Commonly Observed Molecular Dense Gas Tracers
• Building Terrestrial Planets
• Binding energies: new values and impact on the efficiency of chemical desorption
• Water in star-forming regions (WISH): Physics and chemistry from clouds to disks as probed by Herschel spectroscopy
• ALMA hints at the presence of two companions in the disk around HD 100546
• Composition of Early Planetary Atmospheres I: Connecting Disk Astrochemistry to the Formation of Planetary Atmospheres
• Hints for icy pebble migration feeding an oxygen-rich chemistry in the inner planet-forming region of disks
• The depletion of water during dispersal of planet-forming disk regions
• Planet Formation Theory in the Era of ALMA and Kepler: from Pebbles to Exoplanets
• CO emission tracing a warp or radial flow within $\lesssim$ 100 au in the HD 100546 protoplanetary disk
• Resolved images of the protoplanetary disk around HD 100546 with ALMA
• Chemically tracing the water snowline in protoplanetary disks with HCO${}^{+}$
• The Chemical Inventory of the Inner Regions of Planet-forming Disks -- The JWST/MINDS Program
• Sulphur monoxide emission tracing an embedded planet in the HD 100546 protoplanetary disk
• The kinematics and excitation of infrared water vapor emission from planet-forming disks: results from spectrally-resolved surveys and guidelines for JWST spectra
• Gas temperature structure across transition disk cavities
• Candidate Water Vapor Lines to Locate the H${}_2$O Snowline through High-Dispersion Spectroscopic Observations II. The Case of a Herbig Ae Star
• Kinematics and brightness temperatures of transition discs -- A survey of gas substructures as seen with ALMA
• ALMA 870 $\mu$m continuum observations of HD 100546. Evidence of a giant planet on a wide orbit
• Resolved ALMA observations of water in the inner astronomical units of the HL Tau disk
• ALMA high-resolution observations unveil planet formation shaping molecular emission in the PDS 70 disk
• H${}_2$O distribution in the disc of HD 100546 and HD 163296: the role of dust dynamics and planet--disc interaction
• ALMA reveals thermal and non-thermal desorption of methanol ice in the HD 100546 protoplanetary disk
• A high HDO/H${}_2$O ratio in the Class I protostar L1551 IRS5
• Water UV-Shielding in the Terrestrial Planet-Forming Zone: Implications for Oxygen-18 Isotope Anomalies in H2-18O Infrared Emission and Meteorites
• Pristine ices in a planet-forming disk revealed by heavy water

Cited by in corpus (1)

• Zooming into the water snowline: high resolution water observations of the HL Tau disk