2.7.1 https://spdx.org/licenses/ SPDX CC0-1.0 https://spdx.org/licenses/CC0-1.0.html Creative Commons Zero v1.0 Universal CC0 1.0 Universal is the Creative Commons license applicable to all publicly available SPASE metadata descriptions spase://NASA/NumericalData/POLAR/EFI/SC/Potential_PlasmaDensity/Spin/PT6S NASA NumericalData Polar Electric Fields Instrument (EFI), Spacecraft Potential and Plasma Density, Spin Resolution https://doi.org/10.48322/ttha-dc31 2025-12-04T13:31:00Z 2021-04-27T15:38:11 Only known prior ReleaseDate of the metadata 2023-07-30T12:34:56.789 Added DOI and PublicationInfo minted by LFB, metadata versioned up to SPASE 2.6.0, reviewed by LFB 20230727 2025-08-05T13:12:20Z Added ObservedRegion(s). Changed http to https in top-level schemaLocation attribute. Fixed version number separator in top-level schemaLocation attribute. Matched version number in schemaLocation attribute to value in Version tag. ZCB 2025-10-03T10:48:55Z Updated PublishedBy name to match ROR Registry. Added ResourceType and NamingAuthority. ZCB 2025-12-04T13:31:00Z Added MetadataRightsList and RightsList(s). Updated to 2.7.1. ZCB This data consists of the Spacecraft Potential and the Plasma Density, at spacecraft spin resolution, where the Plasma Density is obtained as a function, provided by Dr. Jack Scudder, the PI of the POLAR Hydra investigation. This function was determined by a fit to the POLAR Hydra particle data for 2001/04/01. The relative accuracy of the Plasma Density, estimated from the spacecraft potential on short time scales is ~10-30% depending on plasma conditions. The absolute accuracy is better than a factor of two for densities less than about 20 particles/cm^3. Density values greater than 30 particles/cm^3 are not plotted because they are inaccurate due to the steep slope of the curve of density versus spacecraft potential. If the value of the argument to the function is too large, then the Plasma Density is set to a filler value of 1.0e+20. Also, if the value returned by the function is too large, then the result is not reliable, and therefore the Plasma Density is set to a filler value of 1.0e+20. If the value of the argument to the function is too small, then the Plasma Density is set to a filler value of 1.0e-20. So, a value of the Plasma Density is a filler value if and only if it is either larger than 1.0e+2 (100.0) or smaller than 1.0e-4 (0.0001); otherwise, it is a true value. Note that all values of the Spacecraft Potential are true values. There is no filler. The user will acknowledge, in any publication which uses POLAR EFI data, the instrument PI, as well as the instrument PI for the POLAR Hydra instrument, if the Plasma Density is used. Mozer, Forrest, S. 2023-01-01T00:00:00 Space Physics Data Facility; University of California, Berkeley spase://SMWG/Person/Forrest.S.Mozer PrincipalInvestigator spase://SMWG/Person/Jack.B.Vernetti MetadataContact spase://SMWG/Person/Lee.Frost.Bargatze MetadataContact spase://VWO/NumericalData/POLAR/EFI/SC_Potential_PlasmaDensity_Spin spase://VSPO/NumericalData/POLAR/EFI/Potential/PT6S spase://VSPO/NumericalData/POLAR/EFI/SC/Potential_PlasmaDensity/Spin/PT6S spase://SMWG/Repository/NASA/GSFC/SPDF/CDAWeb Online Open https://spdx.org/licenses/ SPDX CC0-1.0 https://spdx.org/licenses/CC0-1.0.html Creative Commons Zero v1.0 Universal CC0 1.0 Universal is the Creative Commons license applicable to all publicly available NASA Heliophysics data products FTPS from SPDF (not with most browsers) ftps://spdf.gsfc.nasa.gov/pub/data/polar/efi/efi_6secpotldens/ HTTPS from SPDF https://spdf.gsfc.nasa.gov/pub/data/polar/efi/efi_6secpotldens/ In CDF via HTTP from CDAWeb CDAWeb https://cdaweb.gsfc.nasa.gov/cgi-bin/eval2.cgi?dataset=PO_6SECPOTLDENS_EFI&index=sp_phys PO_6SECPOTLDENS_EFI PO_6SECPOTLDENS_EFI CDF spase://SMWG/Repository/NASA/GSFC/SPDF/CDAWeb Online Open https://spdx.org/licenses/ SPDX CC0-1.0 https://spdx.org/licenses/CC0-1.0.html Creative Commons Zero v1.0 Universal CC0 1.0 Universal is the Creative Commons license applicable to all publicly available NASA Heliophysics data products CDAWeb HAPI Server https://cdaweb.gsfc.nasa.gov/hapi PO_6SECPOTLDENS_EFI Web Service to this product using the HAPI interface. CSV spase://SMWG/Repository/UCB/POLAR/EFI Online Open http://polarefi.ssl.berkeley.edu/Polar5_js?Continue%3A=Continue&RequestType%3A=Customized This URL is the root location of the POLAR EFI archive. It consists of Yearly subdirectories: 1996, 1997, ..., 2008 each of which consists of Monthly subdirectories: 01, 02, ..., 12 The archive files for a given date are located in the corresponding YY/MM subdirectory. en CDF None The user will acknowledge, in any publication which uses POLAR EFI data, the instrument PI, as well as the instrument PI for the POLAR Hydra instrument, if the Plasma Density is used. spase://SMWG/Instrument/POLAR/EFI ElectricField ThermalPlasma 1996-03-16T00:00:00 2008-04-12T24:00:00 PT6S Earth.Magnetosphere.Polar Earth.NearSurface.AuroralRegion Earth.Magnetosphere Time TIME_TAG Data point time-tags which are double precision floating point numbers which represent the number of seconds, UTC, from midnight of the day represented by the file. PT6S seconds 0.0 86460.0 Temporal SCPotential DATA_VALUES Data point value which represents the Spacecraft Potential as single precision floating point numbers. The SCPotential values are in in one-to-one correspondence with the values in the TIME_TAG parameter. PT6S Volts -80.0 10.0 Scalar Potential PlasmaDensity DATA_VALUES Data point value which represents the Plasma Density as single precision floating point numbers. Not all times in the TIME_TAG parameter correspond to true PlasmaDensity data, so there are filler values. PT6S Particles/cm^3 0.0001 100.0 1.0e+20,1.0e-20 Scalar PlasmaFrequency