Results 21 to 30 of about 239,951 (165)
Dust Disks Around Young Stellar Objects [PDF]
Journal of Astronomy and Space Sciences, 2016 To reproduce the spectral energy distributions (SEDs) of young stellar objects (YSOs), we perform radiative transfer model calculations for the circumstellar dust disks with various shapes and many dust species.
Kyung-Won Suh
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Composite circumstellar dust grains [PDF]
Monthly Notices of the Royal Astronomical Society, 2016 We calculate the absorption efficiencies of composite silicate grains with inclusions of graphite and silicon carbide in the spectral range 5--25$\rm μm$. We study the variation in absorption profiles with volume fractions of inclusions. In particular we study the variation in the wavelength of peak absorption at 10 and 18$\rm μm$.
Gupta, Ranjan +2 more
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AGB Stars and Their Circumstellar Envelopes. I. the VULCAN Code
Universe, 2021 The interplay between AGB interiors and their outermost layers, where molecules and dust form, is a problem of high complexity. As a consequence, physical processes like mass loss, which depend on the chemistry of the circumstellar envelope, are often ...
Sergio Cristallo +4 more
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Dust Coagulation in Oxygen-rich Circumstellar Outflows
The Astrophysical Journal, 2023 We show that the inefficient growth of SiO molecules on (SiO) _x dust grains prolongs the period of maximum dust nucleation in circumstellar outflows resulting in a several orders-of-magnitude increase in the dust density near the star.
John A. Paquette +2 more
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Astromineralogy of Circumstellar Oxide Dust [PDF]
Publications of the Astronomical Society of the Pacific, 2005 Oxides are among the less abundant species of cosmic dust (as compared, e.g., to silicates). Nevertheless, they are of decisive importance for the first stages of the condensation process in oxygen-rich circumstellar shells of AGB stars. The present work gives an overview of oxygen dust species that have been examined so far by means of astronomical ...
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The temperature of nonspherical circumstellar dust grains [PDF]
Astronomy Letters, 2000 18 pages, 9 figures, to appear in Astronomy Letters, Vol.
Voshchinnikov, N. V., Semenov, D. A.
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Temperature Distributions in Circumstellar Dust Shells [PDF]
Symposium - International Astronomical Union, 1987 The knowledge of the temperature distribution in circumstellar dust shells (CDS) is needed for both the calculation of the emergent IR spectrum and the modelling of physical processes, e.g. dust formation.
Th. Henning, J. Gürtler
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The Astrophysical Journal, 2023 The first step toward planet formation is grain growth from (sub)micrometer to millimeter/centimeter sizes. Grain growth has been reported not only in Class II protoplanetary disks but also in Class 0/I protostellar envelopes.
Ilseung Han +4 more
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The Circumstellar Dust of “Born-Again” Stars [PDF]
EAS Publications Series, 2015 We describe the evolution of the carbon dust shells around Very Late Thermal Pulse (VLTP) objects as seen at infrared wavelengths. This includes a 20-year overview of the evolution of the dust around Sakurai's object (to which Olivier made a seminal contribution) and FG Sge. VLTPs may occur during the endpoint of as many as 25% of solar mass stars, and
Evans, A. +3 more
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International Journal of Chemical Kinetics, Volume 55, Issue 11, Page 731-742, November 2023., 2023 Abstract The kinetics of the tautomerization of thio‐imidic acids RC(SH)NH were determined at low (50–300 K) and high (500–1500 K) temperatures as R was varied to encompass mono‐ and diatomic species H, F, HO, NC, CN through H2N, HC(O), HC(S), HC≡ C, H3C, F3C, HOCH2, H2C=CH, CH3C(O), H2NCH2 and including ethyl, isopropyl and phenyl groups. The presence
Judith Würmel, John M. Simmie
wiley +1 more source