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    <Version>2.2.2</Version>
    <DisplayData>
        <ResourceID>spase://NASA/DisplayData/IMAGE/FUV/SI/O_N2_Ratios</ResourceID>
        <ResourceHeader>
            <ResourceName>IMAGE FUV SI plots of O/N2 Ratios</ResourceName>
            <ReleaseDate>2020-07-07T19:48:33Z</ReleaseDate>
            <Description>This data set consists of images of thermospheric
O/N2 column density ratios at 2-min resolution during times of strong
geomagnetic storms (Dst.LT.-80nT) of 2000-2005. The ratios are generated
from dayside airglow observations of the IMAGE Far Ultraviolet (FUV)
Spectrographic Imager (SI).  The SI has a peak response at the OI 135.6 nm
oxygen emission line and a bandpass of 131.0 to 140.0 nm which includes
the LBH band from N2 molecules. For each O/N2 plot, there is a plot of the
SI image from which the O/N2 plot was generated, and there is an IDL saveset
of the content of the O/N2 maps.  The Information URL of this descriptor
identifies detailed discussions of the derivations of O/N2 rations from the
SI images.</Description>
            <Contact>
                <PersonID>spase://SMWG/Person/Yongliang.Zhang</PersonID>
                <Role>DataProducer</Role>
</Contact>
            <InformationURL>
                <Name>Data descriptive text at JHU_APL</Name>
                <URL>https://image.gsfc.nasa.gov/index.php?documentation</URL>
</InformationURL>
            <PriorID>spase://VSPO/DisplayData/IMAGE/FUV/SI/O_N2_Ratios</PriorID>
</ResourceHeader>
        <AccessInformation>
            <RepositoryID>spase://SMWG/Repository/JHU_APL</RepositoryID>
            <Availability>Online</Availability>
            <AccessRights>Open</AccessRights>
            <AccessURL>
                <Name>IMAGE O/N2 site at JHU/APL</Name>
                <URL>https://image.gsfc.nasa.gov/index.php?data</URL>
                <Description>O/N2 and FUV/SI image plots in PNG format</Description>
</AccessURL>
            <Format>PNG</Format>
</AccessInformation>
        <InstrumentID>spase://SMWG/Instrument/IMAGE/FUV</InstrumentID>
        <MeasurementType>ImageIntensity</MeasurementType>
        <TemporalDescription>
            <TimeSpan>
                <StartDate>2000-05-24T00:00:00</StartDate>
                <StopDate>2005-05-18T23:59:59</StopDate>
</TimeSpan>
            <Cadence>PT2M</Cadence>
</TemporalDescription>
        <ObservedRegion>Earth.NearSurface.Thermosphere</ObservedRegion>
        <Caveats>
(1) O/N2 values are available only for dayside with solar zenith angle less than 90 degrees.
(2) Auroral emissions are not removed. The O/N2 data in the auroral oval should not be used.
The original SI-13 images are also provided in the APL web site to identify auroral regions.
(3) SI-13 flat field algorithm is provided by the IMAGE FUV team. But it may not work
well all the time. This impacts the O/N2 products.
(4) Pointing of SI-13 is still subject to some errors even after attitude correction is done.
(5) A fixed O/N2 value (assumed) for quiet times may ignore the effects of season and
solar EUV flux.</Caveats>
</DisplayData>
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