scholarly journals Correction to “Reactive, Inelastic, and Dissociation Processes in Collisions of Atomic Oxygen with Molecular Nitrogen”

2020 ◽  
Vol 124 (7) ◽  
pp. 1465-1465 ◽  
Author(s):  
F. Esposito ◽  
I. Armenise
Keyword(s):  
Atomic Oxygen ◽  
Molecular Nitrogen

scholarly journals Vertical circulation and thermospheric composition: a modelling study

1999 ◽  
Vol 17 (6) ◽  
pp. 794-805 ◽  
Author(s):  
H. Rishbeth ◽  
I. C. F. Müller-Wodarg
Keyword(s):  
Concentration Ratio ◽  
Atomic Oxygen ◽  
Molecular Nitrogen ◽  
Three Dimensional ◽  
Atmospheric Composition ◽  
Vertical Circulation ◽  
Energy Inputs ◽  
Composition And Structure ◽  
Vertical Distributions ◽  
Summer Hemisphere

Abstract. The coupled thermosphere-ionosphere-plasmasphere model CTIP is used to study the global three-dimensional circulation and its effect on neutral composition in the midlatitude F-layer. At equinox, the vertical air motion is basically up by day, down by night, and the atomic oxygen/molecular nitrogen [O/N2] concentration ratio is symmetrical about the equator. At solstice there is a summer-to-winter flow of air, with downwelling at subauroral latitudes in winter that produces regions of large [O/N2] ratio. Because the thermospheric circulation is influenced by the high-latitude energy inputs, which are related to the geometry of the Earth's magnetic field, the latitude of the downwelling regions varies with longitude. The downwelling regions give rise to large F2-layer electron densities when they are sunlit, but not when they are in darkness, with implications for the distribution of seasonal and semiannual variations of the F2-layer. It is also found that the vertical distributions of O and N2 may depart appreciably from diffusive equilibrium at heights up to about 160 km, especially in the summer hemisphere where there is strong upwelling. Atmospheric composition and structure (thermosphere · composition and chemistry) · Ionosphere (ionosphere · atmosphere interactions)

Method of monitoring atomic oxygen and molecular nitrogen composition in the upper atmosphere on XUV images of the Sun

2010 ◽  
Vol 50 (5) ◽  
pp. 679-685 ◽  
Author(s):  
V. G. Mordovskaya ◽  
A. P. Ignat’ev ◽  
S. I. Boldyrev ◽  
S. A. Boldyrev ◽  
G. S. Ivanov-Kholodnyi ◽  
...  
Keyword(s):  
Atomic Oxygen ◽  
Molecular Nitrogen ◽  
Upper Atmosphere ◽  
The Sun

scholarly journals Daily Variability in the Terrestrial UV Airglow

Atmosphere ◽  
2020 ◽  
Vol 11 (10) ◽  
pp. 1046
Author(s):  
Thomas J. Immel ◽  
Richard W. Eastes ◽  
William E. McClintock ◽  
Steven B. Mende ◽  
Harald U. Frey ◽  
...  
Keyword(s):  
Atomic Oxygen ◽  
Molecular Nitrogen ◽  
Universal Time ◽  
Geosynchronous Orbit ◽  
Direct Connection ◽  
Instrument Response ◽  
Regional Source ◽  
Extreme Uv ◽  
Geographic Regions ◽  
Lower Correlation

New capability for observing conditions in the upper atmosphere comes with the implementation of global ultraviolet (UV) imaging from geosynchronous orbit. Observed by the NASA GOLD mission, the emissions of atomic oxygen (OI) and molecular nitrogen (N2) in the 133–168-nm range can be used to characterize the behavior of these major constituents of the thermosphere. Observations in the ultraviolet from the first 200 days of 2019 indicate that the oxygen emission at 135.6 nm varies much differently than the broader Lyman-Birge-Hopfield (LBH) emission of N2. This is determined from monitoring the average instrument response from two roughly 1000 km2 areas, well separated from one another, at the same time of each day. Variations in the GOLD response to UV emissions in the monitored regions are determined, both in absolute terms and relative to a running 7-day average of GOLD measurements. We find that variations in N2 emissions in the two separate regions are significantly correlated, while oxygen emissions, observed in the same fixed geographic regions at the same universal time each day, exhibit a much lower correlation, and exhibit no correlation with the N2 emissions in the same regions. This indicates that oxygen densities in the airglow-originating altitude range of 150–200 km vary independently from the variations in nitrogen, which are so well correlated across the dayside to suggest a direct connection to variation in solar extreme-UV flux. The relation of the atomic oxygen variations to solar and geomagnetic activity is also shown to be low, suggesting the existence of a regional source that modifies the production of atomic oxygen in the thermosphere.

scholarly journals Thermospheric Parameters during Ionospheric G-Conditions

2021 ◽  
Vol 13 (17) ◽  
pp. 3440
Author(s):  
Loredana Perrone ◽  
Andrey V. Mikhailov ◽  
Dario Sabbagh
Keyword(s):  
Atomic Oxygen ◽  
Molecular Nitrogen ◽  
Retrieval Process ◽  
Gas Density ◽  
Oxygen Abundance ◽  
Plasma Drift ◽  
Neutral Gas ◽  
Thermospheric Winds ◽  
First Time ◽  
Exospheric Temperature

For the first time thermospheric parameters (neutral composition, exospheric temperature and vertical plasma drift related to thermospheric winds) have been inferred for ionospheric G-conditions observed with Millstone Hill ISR on 11–13 September 2005; 13 June 2005, and 15 July 2012. The earlier developed method to extract a consistent set of thermospheric parameters from ionospheric observations has been revised to solve the problem in question. In particular CHAMP/STAR and GOCE neutral gas density observations were included into the retrieval process. It was found that G-condition days were distinguished by enhanced exospheric temperature and decreased by ~2 times of the column atomic oxygen abundance in a comparison to quiet reference days, the molecular nitrogen column abundance being practically unchanged. The inferred upward plasma drift corresponds to strong ~90 m/s equatorward thermospheric wind presumably related to strong auroral heating on G-condition days.

scholarly journals Reconciling Experimental and Theoretical Vibrational Deactivation in Low-Energy O+N2 Collisions

2021 ◽  
Author(s):  
Qizhen Hong ◽  
Massimiliano Bartolomei ◽  
Fabrizio Esposito ◽  
Cecilia Coletti ◽  
Quanhua Sun ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Atomic Oxygen ◽  
Room Temperature ◽  
Molecular Nitrogen ◽  
Low Energy ◽  
Inelastic Collisions ◽  
Experimental Results ◽  
Molecular Dynamics Calculations

Molecular dynamics calculations of inelastic collisions of atomic oxygen with molecular nitrogen are known to show orders of magnitude discrepancies with experimental results in the range from room temperature to...

scholarly journals Simultaneous imaging of aurora on small scale in OI (777.4 nm) and N<sub>2</sub>1P to estimate energy and flux of precipitation

2009 ◽  
Vol 27 (7) ◽  
pp. 2881-2891 ◽  
Author(s):  
B. S. Lanchester ◽  
M. Ashrafi ◽  
N. Ivchenko
Keyword(s):  
Temporal Resolution ◽  
Atomic Oxygen ◽  
Molecular Nitrogen ◽  
Low Energy ◽  
Optical Measurements ◽  
Small Scale ◽  
Emission Rates ◽  
Simultaneous Imaging ◽  
Radar Measurements ◽  
Multispectral Imager

Abstract. Simultaneous images of the aurora in three emissions, N21P (673.0 nm), OII (732.0 nm) and OI (777.4 nm), have been analysed; the ratio of atomic oxygen to molecular nitrogen has been used to provide estimates of the changes in energy and flux of precipitation within scale sizes of 100 m, and with temporal resolution of 32 frames per second. The choice of filters for the imagers is discussed, with particular emphasis on the choice of the atomic oxygen line at 777.4 nm as one of the three emissions measured. The optical measurements have been combined with radar measurements and compared with the results of an auroral model, hence showing that the ratio of emission rates OI/N2 can be used to estimate the energy within the smallest auroral structures. In the event chosen, measurements were made from mainland Norway, near Troms\\o, (69.6 N, 19.2 E). The peak energies of precipitation were between 1–15 keV. In a narrow curling arc, it was found that the arc filaments resulted from energies in excess of 10 keV and fluxes of approximately 7 mW/m2. These filaments of the order of 100 m in width were embedded in a region of lower energies (about 5–10 keV) and fluxes of about 3 mW/m2. The modelling results show that the method promises to be most powerful for detecting low energy precipitation, more prevalent at the higher latitudes of Svalbard where the multispectral imager, known as ASK, is now installed.

Sign in / Sign up

Export Citation Format

Share Document