ros-lap-asw.xml
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<?xml version="1.0" encoding="UTF-8"?>
<Spase xmlns="http://www.spase-group.org/data/schema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.spase-group.org/data/schema http://cdpp.irap.omp.eu/AMDA-NG/public/schemas/spase-amda-1_2_0.xsd">
<Version>2.2.6</Version>
<NumericalData>
<ResourceID>spase://CDPP/NumericalData/AMDA/Rosetta/LAP/ros-lap-asw</ResourceID>
<ResourceHeader>
<ResourceName>parameters from sweeps (ASW)</ResourceName>
<AlternateName>Analyzed sweeps (ASW). Miscellaneous physical
high-level quantities derived from individual sweeps.</AlternateName>
<ReleaseDate>2016-10-15T14:08:29Z</ReleaseDate>
<Description>Time series of sweep-based estimates of electron
density, ion bulk speed, electron temperature, and photoelectron knee
potential. Timestamps represent the middle of the corresponding sweeps.</Description>
<Contact>
<PersonID>spase://CDPP/Person/Anders.Eriksson</PersonID>
<Role>PrincipalInvestigator</Role>
</Contact>
<Contact>
<PersonID>spase://CDPP/Person/Erik.Johansson</PersonID>
<Role>DataProducer</Role>
</Contact>
<InformationURL>
<Name>RPC LAP User Guide</Name>
<URL>http://amda.irap.omp.eu/help/parameters/RO-IRFU-LAP-UG.PDF</URL>
</InformationURL>
<InformationURL>
<Name>ROSETTA RPC-LAP to Planetary Science Archive Interface Control Document</Name>
<URL>http://amda.irap.omp.eu/help/parameters/RO-IRFU-LAP-EAICD_2_0_1_PDF_A.PDF</URL>
</InformationURL>
</ResourceHeader>
<AccessInformation>
<RepositoryID>spase://SMWG/Repository/CDPP/AMDA</RepositoryID>
<Availability>Online</Availability>
<AccessRights>Restricted</AccessRights>
<AccessURL>
<URL>http://amda.cdpp.eu</URL>
</AccessURL>
<Format>NetCDF</Format>
</AccessInformation>
<ProviderName>PSA</ProviderName>
<ProviderResourceName>RO-C-RPCLAP-5-xxx-DERIV2-V1.0</ProviderResourceName>
<InstrumentID>spase://CDPP/Instrument/AMDA/Rosetta/LAP</InstrumentID>
<MeasurementType>ThermalPlasma</MeasurementType>
<TemporalDescription>
<TimeSpan>
<StartDate>2014-03-24T08:12:59Z</StartDate>
<StopDate>2016-09-30T10:31:16Z</StopDate>
</TimeSpan>
<Cadence_Min>PT0.016S</Cadence_Min>
<Cadence_Max>PT128S</Cadence_Max>
</TemporalDescription>
<Caveats>* n_e - electron density is calculated from the slope of the probe curve where electron collection dominates, which should be proportional to the plasma density divided by the square root of the electron temperature [Eriksson et al., 2017]. An electron temperature is assumed to be fixed (value of 5 eV) which has been found suitable for giving densities comparable to MIP at the points where both instruments have data. A user who wishes to use another fixed Te, or use the sweep derived T_E, may scale N_E by the square root of Te/(5 eV). While N_E works well in low density plasmas, severe underestimation can result in high density plasmas where Vsc becomes very negative.
* i_photosat - photosaturation current derived from individual sweep (LAP1). As LAP1 has shown no significant contamination effects, these estimates should be directly proportional to the EUV flux at Rosetta position in the 20-130 nm band.
* v_i bulk - effective ion speed derived from individual sweep (speed; always non-negative scalar), while assuming a specific ion mass. Cross-calibrated with RPCMIP.
* t_e - electron temperature derived from exponential part of sweep. The temperature from the exponential slope of the retarding electron current (a least-square fit slope of the logarithm of the current, after subtraction of a fitted ion current) refers to the warm electron population. If the automatic identification of the retarding electron current region is poor, this estimate can be quite noisy and have a large random spread.
* t_e_xcalc - electron temperature, derived by using the linear part of the electron current of the sweep, and density measurement from RPCMIP. The interpretation should be that when T_E_XCAL has a value below 1 eV, there is a cold electron population present. As the relative fractions of the warm and cold electrons are unknown, the provided value of T_E_XCAL should be interpreted as an upper limit to the temperature of the cold electrons.
* It should be noted that the absolute accuracy of the two Te estimates is not well constrained as there is little independent data to compare to. T_E_XCAL should be seen as an approximate upper value for the cold electron temperature, while T_E should not be considered to estimate the warm electron temperature better than by a factor of two.
* u_sc - spacecraft potential derived from the voltage where the photoelectron emission current from the probe transits from being constant at lower votages to decaying with increasing voltage, clearly visible as a knee.
</Caveats>
<Parameter>
<Name>n_e</Name>
<ParameterKey>ros_lap_neft</ParameterKey>
<Description>Electron density derived from individual sweep. An electron temperature is assumed to be fixed (value of 5 eV)</Description>
<Ucd/>
<Units>cm^-3</Units>
<RenderingHints>
<DisplayType>TimeSeries</DisplayType>
</RenderingHints>
<FillValue>-1.e+09</FillValue>
</Parameter>
<Parameter>
<Name>n_e : qual</Name>
<ParameterKey>ros_lap_neft_q</ParameterKey>
<Description>Quality value in the range 0 (worst) to 1 (best). Corresponds to goodness of fit or how well the model fits the data</Description>
<Ucd/>
<Units/>
<RenderingHints>
<DisplayType>TimeSeries</DisplayType>
</RenderingHints>
<FillValue></FillValue>
</Parameter>
<Parameter>
<Name>t_e</Name>
<ParameterKey>ros_lap_te</ParameterKey>
<Description>Electron temperature derived from exponential part of sweep</Description>
<Ucd/>
<Units>eV</Units>
<RenderingHints>
<DisplayType>TimeSeries</DisplayType>
</RenderingHints>
<FillValue>-1.e+09</FillValue>
</Parameter>
<Parameter>
<Name>t_e : qual</Name>
<ParameterKey>ros_lap_te_q</ParameterKey>
<Description>Quality value in the range 0 (worst) to 1 (best). Corresponds to goodness of fit or how well the model fits the data</Description>
<Ucd/>
<Units/>
<RenderingHints>
<DisplayType>TimeSeries</DisplayType>
</RenderingHints>
<FillValue></FillValue>
</Parameter>
<Parameter>
<Name>t_e_xcalc</Name>
<ParameterKey>ros_lap_te_xcalc</ParameterKey>
<Description>Electron temperature, derived by using the linear part of the electron current of the sweep, and density measurement from RPCMIP.</Description>
<Ucd/>
<Units>eV</Units>
<RenderingHints>
<DisplayType>TimeSeries</DisplayType>
</RenderingHints>
<FillValue>-1.e+09</FillValue>
</Parameter>
<Parameter>
<Name>t_e_xcalc : qual</Name>
<ParameterKey>ros_lap_te_xcalc_q</ParameterKey>
<Description>Quality value in the range 0 (worst) to 1 (best). Corresponds to goodness of fit or how well the model fits the data</Description>
<Ucd/>
<Units/>
<RenderingHints>
<DisplayType>TimeSeries</DisplayType>
</RenderingHints>
<FillValue></FillValue>
</Parameter>
<Parameter>
<Name>i_photosat</Name>
<ParameterKey>ros_lap_ipho</ParameterKey>
<Description>Photosaturation current derived from individual sweep. As LAP1 has shown no significant
contamination effects, these estimates should be directly proportional to the EUV flux at Rosetta position in the 20-130 nm band.</Description>
<Ucd/>
<Units>A</Units>
<RenderingHints>
<DisplayType>TimeSeries</DisplayType>
</RenderingHints>
<FillValue>-1.e+09</FillValue>
</Parameter>
<Parameter>
<Name>i_photosat : qual</Name>
<ParameterKey>ros_lap_ipho_q</ParameterKey>
<Description>Quality value in the range 0 (worst) to 1 (best). Corresponds to goodness of fit or how well the model fits the data</Description>
<Ucd/>
<Units/>
<RenderingHints>
<DisplayType>TimeSeries</DisplayType>
</RenderingHints>
<FillValue></FillValue>
</Parameter>
<Parameter>
<Name>v_i bulk</Name>
<ParameterKey>ros_lap_vi_asw</ParameterKey>
<Description>Effective ion speed derived from individual sweep (speed; always non-negative scalar), while assuming a specific ion mass. Cross-calibrated with RPCMIP</Description>
<Ucd/>
<Units>m/s</Units>
<RenderingHints>
<DisplayType>TimeSeries</DisplayType>
</RenderingHints>
<FillValue>-1.e+09</FillValue>
</Parameter>
<Parameter>
<Name>v_i bulk : qual</Name>
<ParameterKey>ros_lap_vi_asw_q</ParameterKey>
<Description>Quality value in the range 0 (worst) to 1 (best). Corresponds to goodness of fit or how well the model fits the data</Description>
<Ucd/>
<Units/>
<RenderingHints>
<DisplayType>TimeSeries</DisplayType>
</RenderingHints>
<FillValue/>
</Parameter>
<Parameter>
<Name>u_sc</Name>
<ParameterKey>ros_lap_usc_asw</ParameterKey>
<Description>Photoelectron knee potential</Description>
<Ucd/>
<Units>V</Units>
<RenderingHints>
<DisplayType>TimeSeries</DisplayType>
</RenderingHints>
<FillValue>-1.e+09</FillValue>
</Parameter>
<Parameter>
<Name>u_sc : qual</Name>
<ParameterKey>ros_lap_usc_asw_q</ParameterKey>
<Description>Quality value in the range 0 (worst) to 1 (best). Corresponds to goodness of fit or how well the model fits the data</Description>
<Ucd/>
<Units/>
<RenderingHints>
<DisplayType>TimeSeries</DisplayType>
</RenderingHints>
<FillValue/>
</Parameter>
<Parameter>
<Name>quality flag</Name>
<ParameterKey>ros_lap_asw_f</ParameterKey>
<Ucd/>
<Units/>
<RenderingHints>
<DisplayType>TimeSeries</DisplayType>
</RenderingHints>
<FillValue></FillValue>
</Parameter>
</NumericalData>
</Spase>