{
  "id": "MMS4_FPI_SLOW_L2_DES-DIST",
  "url": "https://cdaweb.gsfc.nasa.gov/pub/software/cdawlib/0JSONS/mms4_fpi_slow_l2_des-dist_00000000_v01.json",
  "data-file": "./data/master/info/MMS4_FPI_SLOW_L2_DES-DIST.json",
  "data": {
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        {
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      "CDFglobalAttributes": [
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        {
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              "0": "MMS4>MMS Satellite Number 4"
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        },
        {
          "Discipline": [
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              "0": "Space Physics>Magnetospheric Science"
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        },
        {
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              "0": "slow_l2_des-dist"
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        {
          "Descriptor": [
            {
              "0": "DES>Dual Electron Spectrometers"
            }
          ]
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        {
          "File_naming_convention": [
            {
              "0": "source_descriptor_datatype_yyyyMMddHHmmss"
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        {
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        },
        {
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            {
              "0": "J. Burch, D. Gershman"
            }
          ]
        },
        {
          "PI_affiliation": [
            {
              "0": "SwRI, GSFC"
            }
          ]
        },
        {
          "TEXT": [
            {
              "0": "FPI usually operates in Slow Survey Mode outside of the MMS Region Of Interest (ROI) for the current Mission Phase.  Data captured from one of the four dual spectrometers over three spacecraft spins are reported at about 60 s resolution in this mode.  This product contains phase-space distribution maps of those survey-resolution data from Slow Mode.  In particular, the (highest possible quality at the time of release) corrected/converted \"Slow Survey SkyMap\" distributions are reported with time-stamps and other annotation characterizing the state of the instrument system at the indicated time."
            }
          ]
        },
        {
          "Instrument_type": [
            {
              "0": "Plasma and Solar Wind"
            },
            {
              "1": "Particles (space)"
            }
          ]
        },
        {
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            {
              "0": "MMS"
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          ]
        },
        {
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            {
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          ]
        },
        {
          "Logical_file_id": [
            {
              "0": " "
            }
          ]
        },
        {
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            {
              "0": "MMS Satellite Number 4 Dual Electron Spectrometer SlowSurvey-resolution instrument distributions"
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          ]
        },
        {
          "Time_resolution": [
            {
              "0": "60 seconds"
            }
          ]
        },
        {
          "Rules_of_use": [
            {
              "0": "See FPI Version Release Notes (https://lasp.colorado.edu/mms/sdc/public/datasets/fpi/) for rules of use."
            }
          ]
        },
        {
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            {
              "0": "FPI ITF, NASA/GSFC Code 673"
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        },
        {
          "Generation_date": [
            {
              "0": " "
            }
          ]
        },
        {
          "Generation_site": [
            {
              "0": " "
            }
          ]
        },
        {
          "MODS": [
            {
              "0": "See FPI Version Release Notes (https://lasp.colorado.edu/mms/sdc/public/datasets/fpi/) for data set modification history."
            }
          ]
        },
        {
          "LINK_TEXT": [
            {
              "0": "MMS home page"
            },
            {
              "1": "SMART package home page"
            },
            {
              "2": "Science Data Center"
            },
            {
              "3": "FPI overview"
            }
          ]
        },
        {
          "LINK_TITLE": [
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              "0": "at GSFC"
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            {
              "1": "at SWRI"
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            {
              "2": "at LASP"
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            {
              "3": "at NASA"
            }
          ]
        },
        {
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              "0": "http://mms.gsfc.nasa.gov"
            },
            {
              "1": "http://mms.space.swri.edu"
            },
            {
              "2": "http://lasp.colorado.edu/mms/sdc"
            },
            {
              "3": "http://www.nasa.gov/mission_pages/mms/spacecraft/instruments.html#fpi"
            }
          ]
        },
        {
          "Skeleton_version": [
            {
              "0": " "
            }
          ]
        },
        {
          "Skeleton_revdate": [
            {
              "0": " "
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          ]
        },
        {
          "Correction_table_name": [
            {
              "0": " "
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          ]
        },
        {
          "Correction_table_rev": [
            {
              "0": " "
            }
          ]
        },
        {
          "Energy_table_name": [
            {
              "0": " "
            }
          ]
        },
        {
          "Dead_time_correction": [
            {
              "0": " "
            }
          ]
        },
        {
          "Correction_table_scaling_factor": [
            {
              "0": " "
            }
          ]
        },
        {
          "Quadrant": [
            {
              "0": " "
            }
          ]
        }
      ],
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        {
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                {
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            {
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                  "CATDESC": "Nanoseconds since J2000"
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                {
                  "FIELDNAM": "Time tags"
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                {
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                {
                  "REFERENCE_POSITION": "Rotating Earth Geoid"
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                {
                  "TIME_BASE": "J2000"
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                {
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                  "UNITS": "ns"
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                {
                  "VALIDMIN": "1990-01-01T00:00:00.000000000"
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                {
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                {
                  "VAR_NOTES": "MMS4 FPI/DES Slow Survey data begin-time; derived from packet time."
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              ]
            },
            {
              "VarAttributes": [
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                {
                  "VAR_TYPE": "data"
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            },
            {
              "VarAttributes": [
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                {
                  "LABLAXIS": "compressFlag"
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                {
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                {
                  "UNITS": "0, 1"
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                {
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                },
                {
                  "VALIDMAX": 1
                },
                {
                  "VAR_NOTES": "FPI/DES compression loss indicator, 0=lossless, 1=lossy"
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                {
                  "VAR_TYPE": "data"
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              ]
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                {
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                {
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                {
                  "VAR_NOTES": "Nominally, spin-phase angles range over [0, 360) deg.  Each count represents 1/16 deg of observatory spin-phase.  Zero spin-phase angle indicates obs +X-axis aligned with the sun-sensor axis."
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            }
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        },
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                    "VARY",
                    "VARY"
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                  "PadValue": -1e+30
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              ]
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            {
              "VarAttributes": [
                {
                  "CATDESC": "MMS4 FPI/DES Slow Survey sky-map instrument distribution"
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                {
                  "VAR_NOTES": "Az bin: sector ind=00 looks \"after\" (spin-phase) Sun, ..., sector ind=15 looks \"before\" Sun dir.  Head field-of-view: pixel index=00 looks to zenith, ..., pixel index=15 looks to nadir.  FPI operations nominally bin data from 64 energy filters into 32 pairwise energy bins, indexed 0-31.  Nominally, bins are indexed in increasing energy order.  See FPI docs for details."
                },
                {
                  "VAR_TYPE": "data"
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                    "VARY"
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                {
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                {
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                {
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                {
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                {
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                {
                  "VALIDMAX": 1e+30
                },
                {
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                {
                  "FORMAT": "A11"
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                {
                  "VAR_NOTES": "Azimuth bin labels"
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                "171.5 deg",
                "194.0 deg",
                "216.5 deg",
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