Optical properties of meteoric smoke analogues
<p><strong>Abstract.</strong> Accurate determination of the optical properties of analogues for meteoric smoke particles (MSPs), which are thought to be composed of iron-rich oxides or silicates, is important for their observation and characterization in the atmosphere. In this stu...
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| Hauptverfasser: | , , , , , , |
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| Dokumenttyp: | Article (Journal) |
| Sprache: | Englisch |
| Veröffentlicht: |
11 Oct 2019
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| In: |
Atmospheric chemistry and physics. Discussions
Year: 2019, Jahrgang: 19, Heft: 19, Pages: 12767-12777 |
| ISSN: | 1680-7375 |
| DOI: | https://doi.org/10.5194/acp-19-12767-2019 |
| Online-Zugang: | Verlag, Volltext: https://doi.org/https://doi.org/10.5194/acp-19-12767-2019 Verlag: https://www.atmos-chem-phys.net/19/12767/2019/ 
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| Verfasserangaben: | Tasha Aylett, James S. A. Brooke, Alexander D. James, Mario Nachbar, Denis Duft, Thomas Leisner, and John M. C. Plane |
| Zusammenfassung: | <p><strong>Abstract.</strong> Accurate determination of the optical properties of analogues for meteoric smoke particles (MSPs), which are thought to be composed of iron-rich oxides or silicates, is important for their observation and characterization in the atmosphere. In this study, a photochemical aerosol flow system (PAFS) has been used to measure the optical extinction of iron oxide MSP analogues in the wavelength range 325-675 nm. The particles were made photochemically and agglomerate into fractal-like particles with sizes on the order of 100 nm. Analysis using transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX) and electron energy loss spectroscopy (EELS) suggested the particles were most likely maghemite-like (<span class="inline-formula"><i>γ</i></span>-<span class="inline-formula">Fe<sub>2</sub>O<sub>3</sub></span>) in composition, though a magnetite-like composition could not be completely ruled out. Assuming a maghemite-like composition, the optical extinction coefficients measured using the PAFS were combined with maghemite absorption coefficients measured using a complementary experimental system (the MICE-TRAPS) to derive complex refractive indices that reproduce both the measured absorption and extinction.</p> |
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| Beschreibung: | Gesehen am 17.12.2019 |
| Beschreibung: | Online Resource |
| ISSN: | 1680-7375 |
| DOI: | https://doi.org/10.5194/acp-19-12767-2019 |