High-temperature dust formation in carbon-rich astrophysical environments
arXiv:2411.11529 · doi:10.1038/s41550-024-02393-7
Abstract
Condensation processes, which are responsible for the main chemical differences between gas and solids in the Galaxy, are the major mechanisms that control the cycle of dust from evolved stars to planetary systems. However, they are still poorly understood, mainly because the thermodynamics and kinetic models of nucleation or grain growth lack experimental data. To bridge this gap, we used a large-volume three-phase alternating-current plasma torch to obtain a full high-temperature condensation sequence at an elevated carbon-to-oxygen ratio from a fluxed chondritic gas composition. We show that the crystallized suites of carbides, silicides, nitrides, sulfides, oxides and silicates and the bulk composition of the condensates are properly modelled by a kinetically inhibited condensation scenario controlled by gas flow. This validates the thermodynamic predictions of the condensation sequence at a high carbon-to-oxygen ratio. On this basis and using appropriate optical properties, we also demonstrate the influence of pressure on dust chemistry as well as the low probability of forming and detecting iron silicides in asymptotic giant branch C-rich circumstellar environments as well as in our chondritic meteorites. By demonstrating the potential of predicting dust mineralogy in these environments, this approach holds high promise for quantitatively characterizing dust composition and formation in diverse astrophysical settings.
19 pages, 10 figures, paper published in Nature Astronomy
References in corpus (20)
- The chemical composition of the Sun
- The Dawes Review 2: Nucleosynthesis and stellar yields of low and intermediate-mass single stars
- The absence of crystalline silicates in the diffuse interstellar medium
- (Sub)stellar companions shape the winds of evolved stars
- 2D Models for Dust-driven AGB Star Winds
- Chemical equilibrium in AGB atmospheres: Successes, failures, and prospects for small molecules, clusters, and condensates
- Carbon-rich dust past the asymptotic giant branch: aliphatics, aromatics, and fullerenes in the Magellanic Clouds
- Near-infrared absorption properties of oxygen-rich stardust analogues: The influence of coloring metal ions
- Exploring wind-driving dust species in cool luminous giants I. Basic criteria and dynamical models of M-type AGB stars
- Silicon carbide absorption features: dust formation in the outflows of extreme carbon stars
- Water content and wind acceleration in the envelope around the oxygen-rich AGB star IK Tau as seen by Herschel/HIFI
- Global 3D radiation-hydrodynamical models of AGB stars with dust-driven winds
- Nucleation of small silicon carbide dust clusters in AGB stars
- Developing a self-consistent AGB wind model: II. Non-classical, non-equilibrium polymer nucleation in a chemical mixture
- Some optical properties of graphite from IR to millimetric wavelengths
- Dust Formation in Astrophysical Environments: The Importance of Kinetics
- Understanding the evolution and dust formation of carbon stars in the LMC with a look at the JWST
- The surprisingly carbon-rich environment of the S-type star W Aql
- Condensation of cometary silicate dust using an induction thermal plasma system I. Enstatite and CI chondritic composition
- TEM analyses of unusual presolar silicon carbide: Insights into the range of circumstellar dust condensation conditions