In:
Atmospheric Chemistry and Physics, Copernicus GmbH, Vol. 19, No. 19 ( 2019-10-11), p. 12767-12777
Abstract:
Abstract. 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 (γ-Fe2O3) 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.
Type of Medium:
Online Resource
ISSN:
1680-7324
DOI:
10.5194/acp-19-12767-2019
DOI:
10.5194/acp-19-12767-2019-supplement
Language:
English
Publisher:
Copernicus GmbH
Publication Date:
2019
detail.hit.zdb_id:
2092549-9
detail.hit.zdb_id:
2069847-1
