Three-component modelling of C-rich AGB star winds V. Effects of frequency-dependent radiative transfer including drift

Abstract

Stellar winds of cool carbon stars enrich the interstellar medium with significant amounts of carbon and dust. We present a study of the influence of two-fluid flow on winds where we add descriptions of frequency-dependent radiative transfer. Our radiation hydrodynamic models in addition include stellar pulsations, grain growth and ablation, gas-to-dust drift using one mean grain size, dust extinction based on both the small particle limit and Mie scattering, and an accurate numerical scheme. We calculate models at high spatial resolution using 1024 gridpoints and solar metallicities at 319 frequencies, and we discern effects of drift by comparing drift models to non-drift models. Our results show differences of up to 1000 per cent in comparison to extant results. Mass-loss rates and wind velocities of drift models are typically, but not always, lower than in non-drift models. Differences are larger when Mie scattering is used instead of the small particle limit. Amongst other properties, the mass-loss rates of the gas and dust, dust-to-gas density ratio, and wind velocity show an exponential dependence on the dust-to-gas speed ratio. Yields of dust in the least massive winds increase by a factor four when drift is used. We find drift velocities in the range 10-67 km/s, which is drastically higher than in our earlier works that use grey radiative transfer. It is necessary to include an estimate of drift velocities to reproduce high yields of dust and low wind velocities.

arXiv comment32 pages, 19 figures, accepted for publication in MNRAS

References in corpus (37)

• Models of circumstellar molecular radio line emission: Mass loss rates for a sample of bright carbon stars
• Multiple Molecular Winds in Evolved Stars I. A Survey of CO(2-1) and CO(3-2) Emission from 45 Nearby AGB Stars
• Luminosities and mass-loss rates of SMC and LMC AGB stars and Red Supergiants
• Synthetic photometry for carbon rich giants, I. Hydrostatic dust-free models
• The Mass-Loss Return From Evolved Stars to The Large Magellanic Cloud VI: Luminosities and Mass-Loss Rates on Population Scales
• Dusty winds: I. Self-similar solutions
• 2D Models for Dust-driven AGB Star Winds
• Dust driven mass loss from carbon stars as a function of stellar parameters - I. A grid of Solar-metallicity wind models
• The Mass-Loss Return From Evolved Stars to the LMC: Empirical Relations for Excess Emission at 8 and 24 μm
• Dynamic atmospheres and winds of cool luminous giants, I. Al${}_2$O${}_3$ and silicate dust in the close vicinity of M-type AGB stars
• New observations and models of circumstellar CO line emission of AGB stars in the Herschel SUCCESS programme
• The Fundamentally Different Dynamics of Dust and Gas in Molecular Clouds
• The mass-loss return from evolved stars to the Large Magellanic Cloud V. The GRAMS carbon-star model grid
• Origin of quasi-periodic shells in dust forming AGB winds
• AGB Stars in the Fornax Dwarf Spheroidal Galaxy
• Obscured AGB stars in the Magellanic Clouds II. Near-infrared and mid-infrared counterparts
• The Mass-Loss Return from Evolved Stars to the Large Magellanic Cloud IV: Construction and Validation of a Grid of Models for Oxygen-Rich AGB Stars, Red Supergiants, and Extreme AGB Stars
• Synthetic photometry for carbon-rich giants. IV. An extensive grid of dynamic atmosphere and wind models
• Probing the mass loss history of carbon stars using CO line and dust continuum emission
• The 12CO/13CO ratio in AGB stars of different chemical type-Connection to the 12C/13C ratio and the evolution along the AGB
• Mass Loss Evolution and the Formation of Detached Shells around TP-AGB Stars
• On the metallicity dependence of crystalline silicates in oxygen-rich asymptotic giant branch stars and red supergiants
• The Mass-Loss Return from Evolved Stars to the Large Magellanic Cloud II: Dust Properties for Oxygen-Rich Asymptotic Giant Branch Stars
• The origin of carbon: Low-mass stars and an evolving, initially top-heavy IMF?
• The mass-loss, expansion velocities and dust production rates of carbon stars in the Magellanic Clouds
• Estimating the dust production rate of carbon stars in the Small Magellanic Cloud
• Modelling the alumina abundance of oxygen-rich evolved stars in the Large Magellanic Cloud
• Carbon star wind models at solar and sub-solar metallicities: a comparative study. I. Mass loss and the properties of dust-driven winds
• Dust formation in winds of long-period variables. V. The influence of micro-physical dust properties in carbon stars
• Three-component modeling of C-rich AGB star winds. II. The effects of drift in long-period variables
• Dust driven mass loss from carbon stars as function of stellar parameters - II. Effects of grain size on wind properties
• Three-component modeling of C-rich AGB star winds I. Method and first results
• Three-component modeling of C-rich AGB star winds III. Micro-physics of drift-dependent dust formation
• Three-component modeling of C-rich AGB star winds IV. Revised interpretation with improved numerical descriptions
• Discovery of stars surrounded by iron dust in the LMC
• Dusty winds II. Observational Implications
• How important are metal-poor AGB stars as cosmic dust producers?

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