{
  "Spase": {
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        "Note": "CC0 1.0 Universal is the Creative Commons license applicable to all publicly available SPASE metadata descriptions"
      }
    },
    "NumericalData": {
      "ResourceID": "spase://NASA/NumericalData/ParkerSolarProbe/FIELDS/RFS/SimpleQuasiThermalNoise/Level3/VariableCadence",
      "NamingAuthority": "NASA",
      "ResourceType": "NumericalData",
      "ResourceHeader": {
        "ResourceName": "Parker Solar Probe/FIELDS Simplified Quasi-Thermal Noise data",
        "DOI": "https://doi.org/10.48322/jdj2-1912",
        "ReleaseDate": "2025-12-04T13:30:20Z",
        "RevisionHistory": {
          "RevisionEvent": [
            {
              "ReleaseDate": "2023-08-31T12:34:56.789Z",
              "Note": "Only known prior ReleaseDate of the metadata"
            },
            {
              "ReleaseDate": "2025-10-06T11:18:36.231Z",
              "Note": "Initial SPASE XML resource description submission, metadata generated by SAB"
            },
            {
              "ReleaseDate": "2025-11-04T23:00:18Z",
              "Note": "Changed http to https in top-level schemaLocation attribute. Fixed version number separator in top-level schemaLocation attribute. Added ResourceType and NamingAuthority. Added DOI. TLK"
            },
            {
              "ReleaseDate": "2025-12-04T13:30:20Z",
              "Note": "Added MetadataRightsList and RightsList(s). Updated to 2.7.1. ZCB"
            }
          ]
        },
        "Description": "Parker Solar Probe/FIELDS Simplified Quasi-Thermal Noise data (SQTN).\nThe SQTN spectroscopy is a method which allows to deduce the electron density and the core temperature of the plasma surrounding a s/c, by using the power spectra acquired from an electric dipole antenna (see [1] for the PSP case, and references therein).\nThere are two dipoles on the PSP/FIELDS experiment [2] exploitable for the SQTN, named V1V2 and V3V4, which are both connected to the FIELDS Radio Frequency Spectrometer (RFS), see [3].\nThe density is deduced from the plasma frequency (fp) detection algorithm, applied to RFS available spectra, with elimination of questionable detection (or false positive) using QTN theory (see [1]). No fp detection results in filling the data by -1e31 (for all variables provided here). In particular, since we are using 2x2m dipoles on PSP, the fp detection is impossible when the local Debye length is larger than about 5m. On a daily basis, the typical rate of validated detection of fp is more than 90% of the available spectra when PSP is within 0.25 AU of the Sun, but this rate may drop to only 20% at larger distances (0.5 AU being the upper limit used to product this CDF file, which corresponds at most to +/- 15 days around the exact date of the PSP perihelion).\nWhen the fp detection is validated, fp errors bars are defined taking into account the RFS_LFR spectral resolution (64 pseudo-logarithmically spaced frequencies in the range of 10 kHz-1.7 MHz), then refined by using QTN theory, and this finally provides the error bars for the density (electron_density_delta). The electron density is then deduced as the most probable value within the error bars, using again QTN theory.\nNote the electron density provided here is fully independant of antennas calibrations and floating potential, but not the electron core temperature which is deduced from the QTN level below fp (see [1]), so the core temperature will be certainly more subject to future improvments of this CDF file (see version and mods, v00 corresponding to the method exactly as published for the two first encounters/perihelions by PSP in [1]).\nAll variables provided here were not subject to post-processing noise filtering nor any interpolation/smoothing of data.\nThe time resolution of the RFS varies with instrument mode, so does these electron data derived from RFS data.  During encounter (when PSP is within 0.25 AU of the Sun), cadence for RFS HFR and LFR spectra is typically about 7 seconds (and about 3.5 seconds during +/- 3 days around the perihelion date from encounter 06). During cruise mode, which is the default mode for operations outside of 0.25 AU, cadence for HFR and LFR spectra is about 56 seconds.\nReferences:\n1. Moncuquet, M., Meyer-Vernet, N., Issautier, K. et al. (2020), Astrophysical Journal Supplement Series, 246:44. https://doi.org/10.3847/1538-4365/ab5a84\n2. Bale, S.D., Goetz, K., Harvey, P.R. et al. Space Sci Rev (2016) 204: 49. https://doi.org/10.1007/s11214-016-0244-5\n3. Pulupa, M., Bale, S. D., Bonnell, J.W. et al. (2017) JGR Space Physics, 122, 2836-2854. https://doi.org/10.1002/2016JA023345",
        "Acknowledgement": "In publications, we recommend to add the following sentence in the acknowledgments: \"The authors acknowledge LESIA (Laboratoire d Etudes Spatiales et Instrumentation en Astrophysique), Observatoire de PARIS, CNRS (Centre National de la Recherche Scientifique) and CNES (Centre National d Etudes Spatiales) for support for production of these data and CDPP (Centre de Donnees de la Physique des Plasmas) for their archiving and provision.\" The PSP/FIELDS data provided here are Publicly available. We suggest contacting Michel.Moncuquet@obspm.fr (LESIA) when using these data and for any further question. For parents data, see PSP/FIELDS Rules of the Road available at http://fields.ssl.berkeley.edu/rules/. XXX why XXX",
        "PublicationInfo": {
          "Authors": "Bale, Stuart D;  Moncuquet, Michel;  Pulupa, Marc;  Quinn, Timothy;  Schroeder, Peter",
          "PublicationDate": "2020-01-01T00:00:00",
          "PublishedBy": "NASA Space Physics Data Facility"
        },
        "Contact": [
          {
            "PersonID": "spase://SMWG/Person/Stuart.D.Bale",
            "Role": "PrincipalInvestigator"
          },
          {
            "PersonID": "spase://SMWG/Person/Robert.M.Candey",
            "Role": "MetadataContact"
          },
          {
            "PersonID": "spase://SMWG/Person/Scott.Boardsen",
            "Role": "MetadataContact"
          }
        ],
        "InformationURL": {
          "Name": "CDPP",
          "URL": "https://www.cdpp.eu",
          "Description": "High Resolution PSP/FIELDS data are available at",
          "Language": "en"
        }
      },
      "AccessInformation": [
        {
          "RepositoryID": "spase://SMWG/Repository/NASA/GSFC/SPDF",
          "Availability": "Online",
          "AccessRights": "Open",
          "RightsList": {
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              "RightsIdentifier": "CC0-1.0",
              "RightsURI": "https://spdx.org/licenses/CC0-1.0.html",
              "RightsName": "Creative Commons Zero v1.0 Universal",
              "Note": "CC0 1.0 Universal is the Creative Commons license applicable to all publicly available NASA Heliophysics data products"
            }
          },
          "AccessURL": [
            {
              "Name": "FTPS from SPDF (not with most browsers)",
              "URL": "ftps://spdf.gsfc.nasa.gov/pub/data/psp/fields/l3/sqtn_rfs_v1v2",
              "Description": "Access to Data in CDF Format via ftps from SPDF"
            },
            {
              "Name": "HTTPS from SPDF",
              "URL": "https://spdf.gsfc.nasa.gov/pub/data/psp/fields/l3/sqtn_rfs_v1v2",
              "Description": "Access to Data in CDF Format via https from SPDF"
            },
            {
              "Name": "CDAWeb",
              "URL": "https://cdaweb.gsfc.nasa.gov/cgi-bin/eval2.cgi?dataset=PSP_FLD_L3_SQTN_RFS_V1V2&index=sp_phys",
              "ProductKey": "PSP_FLD_L3_SQTN_RFS_V1V2",
              "Description": "Access to ASCII, CDF, and Plots via NASA/GSFC CDAWeb"
            }
          ],
          "Format": "CDF",
          "Encoding": "None",
          "Acknowledgement": "Please acknowledge the Principal Investigator . Please acknowledge the Data Providers and CDAWeb when using these Data."
        },
        {
          "RepositoryID": "spase://SMWG/Repository/NASA/GSFC/SPDF",
          "Availability": "Online",
          "AccessRights": "Open",
          "RightsList": {
            "Rights": {
              "SchemeURI": "https://spdx.org/licenses/",
              "RightsIdentifierScheme": "SPDX",
              "RightsIdentifier": "CC0-1.0",
              "RightsURI": "https://spdx.org/licenses/CC0-1.0.html",
              "RightsName": "Creative Commons Zero v1.0 Universal",
              "Note": "CC0 1.0 Universal is the Creative Commons license applicable to all publicly available NASA Heliophysics data products"
            }
          },
          "AccessURL": {
            "Name": "CDAWeb HAPI Server",
            "URL": "https://cdaweb.gsfc.nasa.gov/hapi",
            "Style": "HAPI",
            "ProductKey": "PSP_FLD_L3_SQTN_RFS_V1V2",
            "Description": "Web Service to this product using the HAPI interface."
          },
          "Format": "CSV",
          "Acknowledgement": "Please acknowledge the Principal Investigator . Please acknowledge the Data Providers and CDAWeb when using these Data."
        }
      ],
      "ProcessingLevel": "Calibrated",
      "InstrumentID": "spase://SMWG/Instrument/",
      "MeasurementType": [
        "ElectricField",
        "Waves"
      ],
      "TemporalDescription": {
        "TimeSpan": {
          "StartDate": "2018-10-15T00:00:26.000",
          "StopDate": "2025-03-28T23:59:56.000"
        },
        "Cadence": "PT99999.999S"
      },
      "ObservedRegion": [
        "Heliosphere",
        "Heliosphere.Inner",
        "Heliosphere.NearEarth",
        "Sun.Corona"
      ],
      "Parameter": [
        {
          "Name": "Epoch",
          "ParameterKey": "Epoch",
          "Description": "Universal Time in nanoseconds since 01/01/2000",
          "Caveats": "* Same epoch as each lfr_auto_averages_ch0_V1V2 spectrum in parents files psp_fld_l2_rfs_lfr_*.cdf\nThis Parameter exhibits an increasing Monotonic Progression",
          "Units": "ns",
          "UnitsConversion": "1.0e-9>s",
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            "DisplayType": "TimeSeries",
            "AxisLabel": "epoch",
            "ValueFormat": "I22",
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          },
          "ValidMin": "2018-08-12T00:00:00.000000000",
          "ValidMax": "2050-01-01T00:00:00.000000000",
          "FillValue": "9999-12-31T23:59:59.999999999",
          "Support": {
            "SupportQuantity": "Temporal"
          }
        },
        {
          "Name": "electron_density",
          "Set": "Time series defined by using: Epoch",
          "ParameterKey": "electron_density",
          "Description": "Electron number density",
          "Caveats": "The electron density is deduced from the automatic detection of the plasma frequency in RFS spectra with SQTN spectroscopy (see TEXT_global_attributes)",
          "Cadence": "PT99999.999S",
          "Units": "cm^-3",
          "UnitsConversion": "1.0e-6>m^-3",
          "RenderingHints": {
            "DisplayType": "TimeSeries",
            "AxisLabel": "electron density",
            "ValueFormat": "E13.6",
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          },
          "ValidMin": "0.1",
          "ValidMax": "99999.9",
          "FillValue": "-1.0e+31",
          "Particle": {
            "ParticleType": "Electron",
            "Qualifier": "Scalar",
            "ParticleQuantity": "NumberDensity"
          }
        },
        {
          "Name": "electron_core_temperature",
          "Set": "Time series defined by using: Epoch",
          "ParameterKey": "electron_core_temperature",
          "Description": "Electron core temperature",
          "Caveats": "The electron core temperature is deduced from the QTN level below fp in RFS spectra with SQTN spectroscopy (see TEXT_global_attributes)",
          "Cadence": "PT99999.999S",
          "Units": "eV",
          "UnitsConversion": "1>11604.447Kelvin",
          "RenderingHints": {
            "DisplayType": "TimeSeries",
            "AxisLabel": "electron core temperature",
            "ValueFormat": "E13.6",
            "ScaleMin": "0.687773",
            "ScaleMax": "118.592"
          },
          "ValidMin": "0.01",
          "ValidMax": "999.999",
          "FillValue": "-1.0e+31",
          "Particle": {
            "ParticleType": "Electron",
            "Qualifier": "Scalar",
            "ParticleQuantity": "Temperature"
          }
        },
        {
          "Name": "electron_density_delta",
          "Set": "Time series defined by using: Epoch",
          "ParameterKey": "electron_density_delta",
          "Description": "Uncertainty of electron density",
          "Caveats": "electron_density - electron_density_delta[0] < electron_density < electron_density + electron_density_delta[1]",
          "Cadence": "PT99999.999S",
          "Units": "m^-3",
          "UnitsConversion": "1.0e-6>m^-3",
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          "Structure": {
            "Size": "2"
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          "ValidMax": "99999.9",
          "FillValue": "-1.0e+31",
          "Support": {
            "SupportQuantity": "Housekeeping"
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