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Stability of amorphous circumstellar silicate grains
Astronomische Nachrichten, 1986AbstractBerechnungen innerhalb der klassischen Nukleationstheorie zeigen, daß Mg2SiO4‐Staubteilchen mit Radien von etwa 0,1 μm, die sich mit hoher Wahrscheinlichkeit im zirkumstellaren Raum um Sterne späten Spektraltyps bilden, bei etwa 750 K auskondensieren müssen, um amorph zu bleiben.
Th. Henning, J. Svatoš
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Interstellar grain size spectrum and circumstellar grain-grain collisions
Astrophysics and Space Science, 1982In this paper, grain-grain collisions, which were recently suggested by Biermann and Harwit (1980) to occur in cool circumstellar envelopes and to be responsible for the interstellar grain size spectrum, are investigated. On the basis of the author's fragmentation theory, it is shown that in the result of such collisions size distributions of the typen(
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The Infrared Characteristics of Circumstellar Silicate Grains
1985We have made a theoretical study of the infrared emission from circumstellar shells around late-type giants, with the aim of deriving the infrared characteristics of the silicate grains condensing in these shells. A large grid of models has been compared with observations of optically visible Miras, IRC sources and OH/IR stars.
W. Schutte, A. G. G. M. Tielens
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Interstellar and circumstellar grain formation and survival
Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences, 2001Dust formation is primarily associated with stars in their dying throes, e.g. when low–mass stars reach the red–giant or asymptotic–giant branch (AGB) phase of their evolution, or when massive stars explode as supernovae (SNe). While the contribution of AGB stars to the galactic dust budget is significant, both in terms of variety and quantity, that ...
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Optical properties of circumstellar silicate grains
Astrophysics and Space Science, 1991The optical properties of circumstellar silicate dust grains around oxygen-rich giant stars are investigated with close attention to infrared observations of OH/IR stars. The optical constants are deduced from available astronomical and laboratory data.
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Properties of circumstellar grains in R coronae borealis
Astrophysics and Space Science, 1989Extinction curves for core-mantle and multicored grains containing two allotropic carbons are compared with far-UV extinction observations of the variable star R CrB. A good agreement is reached by multicore grains; but it is found that only during deep minimum considered models of grain do not fit the observational UV extinction.
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Silicon Oxide Nanoparticles Reveal the Origin of Silicate Grains in Circumstellar Environments
Nano Letters, 2006A synergistic effort combining experiments in beams and first principles theoretical investigations is used to propose mechanisms that could lead to the formation of silicates and nanoparticles with silicon-rich cores through agglomeration of SiO, an abundant oxygen-bearing species in space.
Arthur C, Reber +5 more
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Dust Grains and Circumstellar Motion: The Problem of the Henand the Egg
Astrophysics and Space Science, 2000In the last ten years, the number of models of circumstellar envelopes has exponentially increased, both concerning evolved stars and forming stars with their planetary systems. The main progress was intoduction of chemistry and coupling with dynamics.
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