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Low-Temperature Formation of Carbonaceous Dust Grains From PAHs
Astrophysical Journal, 2020 Abstract Carbon is ubiquitous in space and plays a key role in prebiotic chemistry. Astronomical observations have found interstellar carbon in the form of polycyclic aromatic hydrocarbons (PAHs) as well as carbonaceous dust, confirming its presence in both gaseous and solid phases.
Mattanjah S de Vries +2 more
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Carbonaceous grain processing in space and in the laboratory
Advances in Space Research, 1999Laboratory simulations of carbonaceous grain processing which occurs in space are fundamental to outline an evolutionary pathway for these particles. We consider the UV spectral changes induced in hydrogenated carbon grains by thermal annealing, UV irradiation and ion bombardment.
V. MENNELLA +6 more
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On the Nature and Origin of Isolated Olivine Grains in Carbonaceous Chondrites
Geochimica Et Cosmochimica Acta, 1977Abstract Many carbonaceous chondrites contain discrete olivine fragments that have been considered to be primitive material, i.e. direct condensates from the solar nebula or pre-solar system material. Olivine occurring in chondrules and as isolated grains in C3(0) chondrites has been characterized chemically and petrographically.
Harry Younger McSween
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Infrared Spectra of Carbonaceous Chondrites and the Composition of Intertellar Grains
Astrophysics and Space Science, 1975Infrared spectra (7–40 μ) of the carbonaceous chondrites, Cold Bokkeveld, Murray, and Orgueil are compared with phyllosilicate minerals and interstellar grain spectra. Similarities in the position and shape of the silicate feature near 9.8 μ suggest that similar silicate minerals are present in primitive meteorites and the interstellar dust.
A. Zaikowski, R. F. Knacke
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Characterization of Presolar Silicate and Oxide Grains in Primitive Carbonaceous Chondrites
Astrophysical Journal, 2007 Raster ion imaging of the oxygen isotopes with the NanoSIMS ion microprobe has been used to identify presolar grains in two primitive meteorites. Eleven presolar silicates and eight presolar oxides were identified in the primitive carbonaceous chondrite Acfer 094 for abundances of 325 and 360 parts per million (ppm), respectively.
Rhonda Stroud +2 more
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On the Origin of Isolated Olivine Grains in Type 2 Carbonaceous Chondrites
Earth and Planetary Science Letters, 1978Two possibilities exist for the origin of aggregates and isolated grains in C2 meteorites: (1) high-temperature phases that condensed directly from a solar nebular gas accumulated as aggregates and single grains on the parent bodies of carbonaceous chondrites and remained unaltered since, or (2) all high-temperature phases in these meteorites are now ...
Edward Olsen, Lawrence Grossman
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Hydrogenation of PAH molecules through interaction with hydrogenated carbonaceous grains
Phys. Chem. Chem. Phys., 2014Carbonaceous materials contribute to a significant proportion of the interstellar dust inventory. Reactions on such grain surfaces are thought to play important roles in interstellar chemical networks. Of particular importance are reactions involving hydrogen atoms, and pathways to the formation of the most abundant molecular species, H2.
Thrower, John D.; id_orcid 0000-0003-0974-8077 +4 more
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Presolar Spinel Grains From the Murray and Murchison Carbonaceous Chondrites
Geochimica Et Cosmochimica Acta, 2003With a new type of ion microprobe, the NanoSIMS, we determined the oxygen isotopic compo- sitions of small (1m) oxide grains in chemical separates from two CM2 carbonaceous meteorites, Murray and Murchison. Among 628 grains from Murray separate CF (mean diameter 0.15 m) we discovered 15 presolar spinel and 3 presolar corundum grains, among 753 grains ...
Sachiko Amari +2 more
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Experimental study of laboratory-synthesized carbonaceous grains and astrophysical implications
AIP Conference Proceedings, 1994We present here the most recent results obtained in the laboratory from various kinds of carbon‐based submicron grains. The joint use of VUV, IR and Raman spectroscopy allows to characterize them and to determine their structural and spectral properties. We compare our results with similiar data obtained by various authors on other kinds of carbonacous
L. Colangeli +6 more
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Low-temperature condensation of carbonaceous dust grains from PAHs
Proceedings of the International Astronomical Union, 2019AbstractInterstellar carbon has been detected in both gas-phase molecules and solid particles. The goal of this study is to identify the link between these two phases of cosmic carbon. Here we report preliminary results on the low temperature formation of carbonaceous dust grains from gas-phase aromatic hydrocarbon precursors.
Lisseth Gavilan Marin +7 more
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