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AGB stars

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Journal Article
Journal: Elements
Published: 01 December 2014
Elements (2014) 10 (6): 441-446.
..., with ~75% of spherules showing isotopically light C (i.e. 12 C/ 13 C > 92; F ig . 1 a ). The large 12 C enrichments, accompanied by 29 Si and 30 Si enrichments, are consistent with a low-metallicity AGB carbon star origin for many HDs ( Zinner et al. 2006 ). Further evidence of an AGB origin comes...
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Image
Hubble Space Telescope image of the Cat&#x27;s Eye Nebula with an evolved <b>AGB</b> st...
in > Elements
Published: 01 February 2011
Hubble Space Telescope image of the Cat's Eye Nebula with an evolved AGB star at the center. I mage credit : ESA, NASA, HEIC, and the H ubble H eritage T eam (STS c I/AURA)
Journal Article
Published: 01 December 2007
European Journal of Mineralogy (2007) 19 (6): 771-782.
... branch stars (RGB/AGB stars), carbon-rich AGB stars (C-rich AGB stars), supernovæ, Wolf-Rayet stars (W-R stars). (ppm = parts per million, ppb = parts per billion.) Composition Typical sizes [μm ] Abundance Stellar sources nanodiamond 0.003 1400 ppm SNe? SiC (mainstream) 0.1–20...
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Journal Article
Journal: Elements
Published: 01 February 2010
Elements (2010) 6 (1): 13-17.
... the process exothermic. However, these neutrons are unstable and decay with a half-life of about 10 minutes. The challenge for theorists is to identify stellar sites with sufficiently intense sources of neutrons. The site of the s-process has been identified in a certain class of red giant stars (AGB stars...
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Journal Article
Journal: Elements
Published: 01 February 2011
Elements (2011) 7 (1): 23-28.
... medium at the time the Sun was born. The vast majority of presolar grains, including SiC and oxides, derive from dust ejected by asymptotic giant branch (AGB) stars. These stars are highly evolved red giants that expel prodigious quantities of dust in “stellar winds” as they die, greatly enriching...
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Journal Article
Journal: Elements
Published: 01 February 2011
Elements (2011) 7 (1): 17-22.
...Hubble Space Telescope image of the Cat's Eye Nebula with an evolved AGB star at the center. I mage credit : ESA, NASA, HEIC, and the H ubble H eritage T eam (STS c I/AURA) ...
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Journal Article
Published: 01 January 2008
Reviews in Mineralogy and Geochemistry (2008) 68 (1): 55-72.
... stellar abundances. In the ISM conditions are not favorable for dust formation, and no process for further grain growth is known. On the contrary, the average grain size in the interstellar medium (0.025–0.25 μm; Mathis et al. 1977 ) is smaller than what is seen in the shells around AGB stars (0.005...
Journal Article
Published: 01 January 2008
Reviews in Mineralogy and Geochemistry (2008) 68 (1): 31-53.
...”) in which the absorption of a metal-poor satellite galaxy (like the Magellanic Clouds) by the Milky Way initiated a burst of star formation. The number of AGB stars formed during this starburst exceeded that formed by normal galactic star formation, so the former contributed the bulk of the SiC...
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Series: Geological Society, London, Special Publications
Published: 01 January 2006
DOI: 10.1144/GSL.SP.2006.256.01.18
EISBN: 9781862395046
... accepted that these extinct radionuclides were synthesized by nuclear processes in supernova or low-mass Asymptobic Giant Branch (AGB) stars in the vicinity of and shortly before the formation of the solar system (Nelson 2004 ). Most meteorites were formed in parent bodies, and some contain refractory...
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Journal Article
Published: 01 November 2008
American Mineralogist (2008) 93 (11-12): 1693-1720.
... clouds, widely dispersed microscopic dust particles contain approximately a dozen refractory minerals that represent the starting point of planetary mineral evolution. Gravitational clumping into a protoplanetary disk, star formation, and the resultant heating in the stellar nebula produce primary...
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Image
Single presolar silicon carbide grains exhibit a tremendous isotopic variet...
Published: 01 January 2004
in the samples results from 26 Al decay. All data displayed have been obtained on individual grains ranging from 0.3 to 5 μm in size by ion probe measurements ( Amari et al. 1994 , 2001 ). Model predictions in AGB stars are also shown. X grains are thought to be produced in supernovae ( Nittler et al. 1996
Image
Nucleosynthetic model proposed to explain the range of silicon isotope comp...
Published: 01 January 2017
Figure 2 Nucleosynthetic model proposed to explain the range of silicon isotope compositions measured in presolar SiC grains. SN II: Supernovae of Type-II. AGB: Asymptotic Giant Branch stars. The solar isotopic composition is reported for reference. See text for explanations. After Zinner et al
Image
A few examples of isotopic patterns of Ne, Ti and heavy elements in SiC and...
Published: 01 January 2004
the compositions. In the resulting patterns, the isotopes produced by p-, r-process are highly depleted or absent within the resolution of the experiments. These results point to strongly s-process dominated components originating in AGB stars. The spectrum of Kr is somewhat more complex with, in some sets of data
Image
Five stages of formation and early evolution of the Solar System: ( 1 ) For...
in > Elements
Published: 01 February 2013
supernovae and/or asymptotic giant branch (AGB) or red giant stars, are shown in red. Outstanding questions with respect to Solar System formation are shown in blue.
Journal Article
Published: 01 January 2016
Reviews in Mineralogy and Geochemistry (2016) 81 (1): 107-160.
... ⊙ ). The C/O core, thus, becomes increasingly dense and is supported by the pressure of degenerate electrons. Ultimately, He burning starts at the bottom of the He shell outside the C/O core, and the star ascends the asymptotic giant branch (AGB) pathway on the H–R diagram ( Busso et al. 1999 ). The AGB...
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Journal Article
Published: 01 November 2018
Reviews in Mineralogy and Geochemistry (2018) 84 (1): 461-497.
... stage of asymptotic giant branch (AGB) stars are proposed to be consistent with optical properties; however, the processes have not been fully quantitatively modeled. This gap is partly due to the lack of kinetic data for condensation/evaporation of minerals and amorphous materials in the conditions...
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Journal Article
Published: 01 January 2004
Reviews in Mineralogy and Geochemistry (2004) 55 (1): 25-64.
... in the samples results from 26 Al decay. All data displayed have been obtained on individual grains ranging from 0.3 to 5 μm in size by ion probe measurements ( Amari et al. 1994 , 2001 ). Model predictions in AGB stars are also shown. X grains are thought to be produced in supernovae ( Nittler et al. 1996...
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Journal Article
Published: 01 January 2013
Reviews in Mineralogy and Geochemistry (2013) 75 (1): 149-181.
... of the most massive AGB stars may experience carbon burning, which converts 12 C to 20 Ne and 24 Mg, producing an O-Ne-Mg white dwarf. A white dwarf is not always the final state of an intermediate mass star. If it is part of a close binary, it can gain mass from its less evolved companion. The increase...
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Journal Article
Published: 01 January 2002
Reviews in Mineralogy and Geochemistry (2002) 47 (1): 71-100.
...) to re-name this component Ne-R. The G component is thought to be material from the He burning shell of Red Giant AGB stars (e.g., Gallino et al. 1990 ; see also section Origins and History ) and theoretical values for the small, but finite amounts of 20 Ne and 21 Ne accompanying 22 Ne are listed...
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Journal Article
Published: 01 November 2013
Geochemistry: Exploration, Environment, Analysis (2013) 13 (4): 317-336.
... assemblages and provide a better regional understanding of potential metal endowment. Supplementary material: Provides details on the datasets selected in this study and is available at http://www.geolsoc.org.uk/SUP18712 The distinction between stratigraphic assemblages within the AGB has been hampered...
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