The mid-IR water and silicate relation in protoplanetary disks

Abstract

Mid-IR water lines from protoplanetary disks around T Tauri stars have a detection rate of 50\%. Models have identified multiple physical properties of disks such as dust-to-gas mass ratio, dust size power law distribution, disk gas mass, disk inner radius, and disk scale height as potential explanation for the current detection rate. We search for a connection between mid-IR water line fluxes and the strength of the 10~$\mu$m silicate feature. We analyse observed water line fluxes from three blends and compute the 10~$\mu$m silicate feature strength from Spitzer spectra. We use a series of published models, exploring disk dust and gas properties, and the effects of different stars. The models also show that the increasing stellar luminosity enhance simultaneously the strength of this dust feature and the water lines fluxes. No correlation is found between the observed mid-IR water lines and the 10~$\mu$m silicate. Our sample shows the same difference in the peak strength between amorphous and crystalline silicates that was noted in earlier studies, but our models do not support this intrinsic difference in silicate peak strength. Individual properties of our model series are not able to reproduce the most extreme observations, suggesting that more complex dust properties are required. A parametrized settling prescription is able to boost the peak strength by a factor 2 for the standard model. Water line fluxes are unrelated to the composition of the dust. The pronounced regular trends seen in the model results are washed out in the data due to the larger diversity in stellar and disk properties compared to our model series. The disks with with weaker mid-IR water line fluxes are depleted in gas or enhanced in dust in the inner 10~au. In the case of gas depleted disks, settling produces very strong 10~$\mu$m silicate features, with strong peak strength.

References in corpus (30)

• The Spitzer c2d Legacy Results: Star Formation Rates and Efficiencies; Evolution and Lifetimes
• Circumstellar Dust Disks in Taurus-Auriga: The Submillimeter Perspective
• Accretion Disks Around Young Objects. II. Tests of Well-Mixed Models with Ism Dust
• A Submillimeter View of Circumstellar Dust Disks in $\rho$ Ophiuchus
• A 10 micron spectroscopic survey of Herbig Ae star disks: grain growth and crystallization
• CASSIS: The Cornell Atlas of Spitzer/IRS Sources
• Detection of the Water Reservoir in a Forming Planetary System
• Spectral Energy Distributions of T Tauri and Herbig Ae Disks: Grain Mineralogy, Parameter Dependences, and Comparison with ISO LWS Observations
• C2D Spitzer-IRS spectra of disks around T Tauri stars: I. Silicate emission and grain growth
• H2O and OH gas in the terrestrial planet-forming zones of protoplanetary disks
• A Spitzer survey of mid-infrared molecular emission from protoplanetary disks I: Detection rates
• A Spitzer Survey of Mid-Infrared Molecular Emission from Protoplanetary Disks II: Correlations and LTE Models
• The formation and evolution of planetary systems: Grain growth and chemical processing of dust in T Tauri systems
• The thermal structure and the location of the snow line in the protosolar nebula: axisymmetric models with full 3-D radiative transfer
• Crystalline silicates and dust processing in the protoplanetary disks of the Taurus young cluster
• Multiwavelength optical properties of compact dust aggregates in protoplanetary disks
• c2d Spitzer IRS Spectra of Disks around T Tauri Stars. III. [Ne II], [Fe I], and H_2 gas-phase lines
• CO rovibrational emission as a probe of inner disk structure
• C2D Spitzer-IRS spectra of disks around T Tauri stars. IV. Crystalline silicates
• Spectrally resolved pure rotational lines of water in protoplanetary disks
• 8--13 um spectroscopy of YSOs: Evolution of the silicate feature
• Water vapor in the protoplanetary disk of DG Tau
• Probing stellar accretion with mid-infrared hydrogen lines
• Detection of warm water vapour in Taurus protoplanetary discs by Herschel
• A Spitzer Survey of Protoplanetary Disk Dust in the Young Serpens Cloud: How do Dust Characteristics Evolve with Time?
• Measurements of water surface snow lines in classical protoplanetary disks
• C2D Spitzer-IRS spectra of disks around T Tauri stars V. Spectral decomposition
• Understanding the water emission in the mid- and far-IR from protoplanetary disks around T~Tauri stars
• Mid-IR spectra of Pre-Main Sequence Herbig stars: an explanation for the non-detections of water lines
• Continuum and line modeling of disks around young stars II. Line diagnostics for GASPS from the DENT grid

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• The infrared line-emitting regions of T Tauri protoplanetary disks
• A model exploration of NIR ro-vibrational CO emission as a tracer of inner cavities in protoplanetary disks
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