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| Titel |
Atomic oxygen and temperature in the lower thermosphere from the O-STATES
sounding rocket project |
| VerfasserIn |
Jonas Hedin, Jörg Gumbel, Linda Megner, Jacek Stegman, Mikael Seo, Mikhail Khaplanov, Tom Slanger, Konstantinos Kalogerakis, Martin Friedrich, Klaus Torkar, Martin Eberhart, Stefan Löhle, Stefanos Fasoulas |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250133765
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| Publikation (Nr.) |
 EGU/EGU2016-14410.pdf |
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| Zusammenfassung |
| In October 2015 the O-STATES payload was launched twice from Esrange Space Center
(67.9˚ N, 21.1˚ E) in northern Sweden, first into moderately disturbed and then into calm
geomagnetic conditions. The basic idea of O-STATES (“Oxygen Species and Thermospheric
Airglow in The Earth´s Sky”) is that comprehensive information on the composition,
specifically atomic oxygen in the ground state O(3P) and first excited state O(1D), and
temperature of the lower thermosphere can be obtained from a limited set of optical
measurements. Starting point for the analysis are daytime measurements of the
O2(b1 ∑
g+ − X3 ∑
g−) Atmospheric Band system in the spectral region 755-780 nm and
the O(1D-3P) Red Line at 630 nm. In the daytime lower thermosphere, O(1D) is produced by
O2 photolysis and the excited O2(b) state is mainly produced by energy transfer from O(1D)
to the O2(X) ground state. In addition to O2 photolysis, both electron impact on
O(3P) and dissociative recombination of O2+ are major sources of O(1D) in the
thermosphere.
Laboratory studies at SRI International have shown that O2(b) production in vibrational
level v=1 dominates. While O2(b, v=0) is essentially unquenched, O2(b, v=1) is subject to
collisional quenching that is dominated by O at altitudes above 160 km. Hence,
the ratio of the Atmospheric Band emission from O2(b, v=1) and O2(b, v=0) is a
measure of the O density at sufficiently high altitudes. In addition, the spectral
shape of the O2 Atmospheric Band is temperature dependent and spectrally resolved
measurements of the Atmospheric Bands thus provide a measure of atmospheric
temperature.
This O2 Atmospheric Band analysis has been suggested as a new technique for
thermospheric remote sensing under the name Global Oxygen and Temperature (GOAT)
Mapping. With O-STATES we want to characterize the GOAT technique by in-situ analysis
of the O2 Atmospheric Band airglow and the underlying excitation mechanisms. By
performing this dayglow analysis from a rocket payload, detailed local altitude
profiles of the relevant emissions and interacting species can be obtained. The optical
measurements are combined with independent detection of O and O2 (resonance
fluorescence and electrochemical detection) as well as measurements of electron and ion
densities. In this paper we describe the O-STATES project and present first results. |
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