Data Set Information
DATA_SET_NAME VG2 JUP PLS DERIVED ION INBOUND SOLAR WIND 96SEC V1.0
DATA_SET_ID VG2-J-PLS-5-SUMM-ION-INBNDSWIND-96S-V1.0
NSSDC_DATA_SET_ID
DATA_SET_TERSE_DESCRIPTION Voyager 2 Plasma (PLS) data from the Jupiter encounter. The data set provides 96 second averages of the solar wind ion moment and fit data including density, temperature, and velocity.
DATA_SET_DESCRIPTION
Data Set Overview
      =================
      Instrument P.I.       : John D. Richardson
      Data Supplier         : John D. Richardson
      Data sampling rate    : 96 seconds
      Data Set Start Time   : 1979-06-25T00:03:19.072Z
      Data Set Stop Time    : 1979-07-05T09:53:42.070Z

      This data set contains solar wind plasma data upstream of
      Jupiter before the Voyager 2 encounter. Fit and moment
      parameters are given; the fit parameters assume a convected
      isotropic proton Maxwellian distribution. Use of fit
      parameters is recommended as these are normally more accurate.
      Since only the first 72 or last 72 energy/charge channels are
      telemetered to Earth from each M-mode spectra, derived
      parameters change significantly only every other set of
      spectra so the effective time resolution is 196 s.

      Parameters
      ==========

      Data Set Parameter 'ION DENSITY'
      --------------------------------
      Data Set Parameter Name        : ION DENSITY
      Data Set Parameter Unit        : CM**-3
      Sampling Parameter Name        : TIME
      Sampling Parameter Unit        : SECOND
      Minimum Sampling Parameter     : UNK
      Maximum Sampling Parameter     : UNK
      Sampling Parameter Interval    : UNK
      Minimum Available Sampling Int : UNK
      Noise Level                    : UNK

      A derived parameter equaling the number of ions per unit
      volume over a specified range of ion energy, energy/charge,
      or energy/nucleon. Discrimination with regard to mass and or
      charge state is necessary to obtain this quantity, however,
      mass and charge state are often assumed due to instrument
      limitations.

      Many different forms of ion density are derived. Some are
      distinguished by their composition (N+, proton, ion, etc.) or
      their method of derivation (Maxwellian fit, method of
      moments). In some cases, more than one type of density will
      be provided in a single data set. In general, if more than
      one ion species is analyzed, either by moment or fit, a total
      density will be provided which is the sum of the ion
      densities. If a plasma component does not have a Maxwellian
      distribution the actual distribution can be represented as
      the sum of several Maxwellians, in which case the density of
      each Maxwellian is given.

      Data Set Parameter 'ION TEMPERATURE'
      ------------------------------------
      Data Set Parameter Name        : ION TEMPERATURE
      Data Set Parameter Unit        : EV
      Sampling Parameter Name        : TIME
      Sampling Parameter Unit        : SECOND
      Minimum Sampling Parameter     : UNK
      Maximum Sampling Parameter     : UNK
      Sampling Parameter Interval    : UNK
      Minimum Available Sampling Int : UNK
      Noise Level                    : UNK

      A derived parameter giving an indication of the mean
      energy/ion, assuming the shape of the ion energy spectrum to
      be Maxwellian. Given that the ion energy spectrum is not
      exactly Maxwellian, the ion temperature can be defined
      integrally (whereby the mean energy obtained by integrating
      under the actual ion energy spectrum is set equal to the
      integral under a Maxwellian, where the temperature is a free
      parameter for which to solve), or differentially (whereby the
      slopes of the actually ion energy spectrum at various energies
      are matched to the slopes of a corresponding Maxwellian). The
      temperature parameter is often qualified with a range of
      applicable energies. Temperatures can be angularly
      anisotropic. If the ions do not have a Maxwellian distribution
      the actual distribution can be represented as the sum of
      several Maxwellians, each with a separate temperature.

      Data Set Parameter 'ION THERMAL SPEED'
      --------------------------------------
      Data Set Parameter Name        : ION THERMAL SPEED
      Data Set Parameter Unit        : KM/S
      Sampling Parameter Name        : TIME
      Sampling Parameter Unit        : SECOND
      Minimum Sampling Parameter     : UNK
      Maximum Sampling Parameter     : UNK
      Sampling Parameter Interval    : UNK
      Minimum Available Sampling Int : UNK
      Noise Level                    : UNK

      A measure of the velocity associated with the temperature of
      the ions. It is formally defined as the Ion Thermal Speed
      squared equals two times K (Boltzmann's constant) times T
      (temperature of ion) divided by M (ion mass). Each component
      of a plasma has a thermal speed associated with it.

      Data Set Parameter 'ION VELOCITY'
      ---------------------------------
      Data Set Parameter Name        : ION VELOCITY
      Data Set Parameter Unit        : KM/S
      Sampling Parameter Name        : TIME
      Sampling Parameter Unit        : SECOND
      Minimum Sampling Parameter     : UNK
      Maximum Sampling Parameter     : UNK
      Sampling Parameter Interval    : UNK
      Minimum Available Sampling Int : UNK
      Noise Level                    : UNK

      A derived parameter giving the average speed and direction of
      motion of a plasma or plasma component. The velocity can be
      obtained by taking the first moment of the distribution
      function or by simulating the observations with some known
      distribution function, usually a Maxwellian, to the
      distribution. Velocities are given in Heliographic (RTN)
      coordinates:

        R is radially away from sun,
        T is in plane of sun's equator and positive in the direction
          of solar rotation
        N completes right-handed system

      Source Instrument Parameters
      ============================
      Instrument Host ID              : VG2
      Data Set Parameter Name         : ION DENSITY
      Instrument Parameter Name       : ION RATE
      Important Instrument Parameters : 1

      Instrument Host ID              : VG2
      Data Set Parameter Name         : ION DENSITY
      Instrument Parameter Name       : ION CURRENT
      Important Instrument Parameters : 1

      Instrument Host ID              : VG2
      Data Set Parameter Name         : ION VELOCITY
      Instrument Parameter Name       : ION CURRENT
      Important Instrument Parameters : 1

      Instrument Host ID              : VG2
      Data Set Parameter Name         : ION TEMPERATURE
      Instrument Parameter Name       : ION RATE
      Important Instrument Parameters : 1

      Instrument Host ID              : VG2
      Data Set Parameter Name         : ION THERMAL SPEED
      Instrument Parameter Name       : ION RATE
      Important Instrument Parameters : 1

      Instrument Host ID              : VG2
      Data Set Parameter Name         : ION TEMPERATURE
      Instrument Parameter Name       : ION CURRENT
      Important Instrument Parameters : 1

      Instrument Host ID              : VG2
      Data Set Parameter Name         : ION THERMAL SPEED
      Instrument Parameter Name       : ION CURRENT
      Important Instrument Parameters : 1

      Instrument Host ID              : VG2
      Data Set Parameter Name         : ION DENSITY
      Instrument Parameter Name       : PARTICLE MULTIPLE PARAMETERS
      Important Instrument Parameters : 1

      Instrument Host ID              : VG2
      Data Set Parameter Name         : ION TEMPERATURE
      Instrument Parameter Name       : PARTICLE MULTIPLE PARAMETERS
      Important Instrument Parameters : 1

      Data Coverage
      =============
Filename  Records           Start                    Stop
-------------------------------------------------------------------
SWIND.TAB 7547   1979-06-25T00:03:19.072Z  1979-07-05T09:53:42.070Z
DATA_SET_RELEASE_DATE 1997-12-01T00:00:00.000Z
START_TIME 1979-06-25T12:03:19.072Z
STOP_TIME 1979-07-05T09:53:42.070Z
MISSION_NAME VOYAGER
MISSION_START_DATE 1972-07-01T12:00:00.000Z
MISSION_STOP_DATE N/A (ongoing)
TARGET_NAME JUPITER
TARGET_TYPE PLANET
INSTRUMENT_HOST_ID VG2
INSTRUMENT_NAME PLASMA SCIENCE EXPERIMENT
INSTRUMENT_ID PLS
INSTRUMENT_TYPE PLASMA INSTRUMENT
NODE_NAME Planetary Plasma Interactions
ARCHIVE_STATUS ARCHIVED
CONFIDENCE_LEVEL_NOTE
Confidence Level Overview
      =========================
      Inbound solar wind values should be accurate to within a few
      percent for all parameters.

      Missing Data Flag
      =================
      Any column containing a value of -9999.9 or -9.9999 (depending
      upon column format) is a missing data value.
CITATION_DESCRIPTION Richardson, J.D., VG2-J-PLS-5-SUMM-ION-INBNDSWIND-96S-V1.0, VG2 JUP PLS DERIVED ION INBOUND SOLAR WIND 96SEC V1.0, NASA Planetary Data System, 1997.
ABSTRACT_TEXT This data set contains solar wind plasma data upstream of Jupiter before the Voyager 2 encounter. Fit and moment parameters are given; the fit parameters assume a convected isotropic proton Maxwellian distribution. Use of fit parameters is recommended as these are normally more accurate. Since only the first 72 or last 72 energy/charge channels are telemetered to Earth from each M-mode spectra, derived parameters change significantly only every other set of spectra so the effective time resolution is 196 s.
PRODUCER_FULL_NAME JOHN D. RICHARDSON
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