Data Set Information
DATA_SET_NAME VOYAGER 1 SATURN PLASMA DERIVED ION FITS BROWSE 96 SEC
DATA_SET_ID VG1-S-PLS-5-ION-FBR-96.0SEC
NSSDC_DATA_SET_ID 77-084A-06J
DATA_SET_TERSE_DESCRIPTION VOYAGER 1 SATURN PLASMA DERIVED ION FITS BROWSE 96 SEC
DATA_SET_DESCRIPTION
Data Set Overview
    =================
      THIS DATA SET CONTAINS THE ION DENSITIES, TEMPERATURES, AND
      VELOCITIES OBTAINED FROM VOYAGER 1 PLS DATA (VOLTAGE RANGE
      10-5950 EV/Q) AT SATURN BY FITTING THE MEASURED SPECTRA WITH
      ISOTROPIC MAXWELLIAN DISTRIBUTIONS.  IT IS A SUBSET OF THE DATA
      SET VG1-S-PLS-5-ION-FIT-96.0SEC WHICH SHOULD BE OBTAINED BEFORE
      THIS DATA IS USED.  ONLY SPECTRA WHICH HAD DISTINCT CURRENT
      PEAKS WERE FIT.  SPECTRA WERE FIT USING ONE OR TWO ION SPECIES,
      PROTONS AND/OR A HEAVY ION WHICH WAS TAKEN TO BE OXYGEN.
      OUTSIDE L=10-12 ION SPECTRA CHANGE RAPIDLY, SO THE VALUES IN
      THIS DATA SET DO NOT REPRESENT AVERAGE PLASMA CONDITIONS IN THE
      OUTER MAGNETOSPHERE.  A COMPLETE DESCRIPTION OF THIS DATA SET
      IS GIVEN IN RICHARDSON (1986).  DATA FORMAT: FIRST 5 COLUMNS
      ARE TIME TAG (YEAR, DAY, HOUR, MIN SEC.MSEC), FOLLOWED BY
      PROTON DENSITY (CM-3), PROTON TEMPERATURE (EV), HEAVY ION
      DENSITY (CM-3), HEAVY ION TEMPERATURE (EV), AND THREE VELOCITY
      COMPONENTS, (RHO, PHI,Z) IN KM/S.  A CYLINDRICAL COORDINATE
      SYSTEM CENTERED ON THE PLANET IS USED, WITH RHO OUTWARDS FROM
      THE SPIN AXIS, PHI IN THE DIRECTION OF ROTATION, AND Z THE
      DISTANCE ABOVE THE EQUATOR.  EACH ROW HAS THE FORMAT
      (2I4,2I3,F7.3,7E11.3).  VALUES OF 1.E32 INDICATE THAT THE
      PARAMETER COULD NOT BE OBTAINED FROM THE DATA USING THE
      STANDARD ANALYSIS TECHNIQUE.  ADDITIONAL INFORMATION ABOUT THIS
      DATASET AND THE INSTRUMENT WHICH PRODUCED IT CAN BE FOUND
      ELSEWHERE IN THIS CATALOG.  AN OVERVIEW OF THE DATA IN THIS
      DATA SET CAN BE FOUND IN RICHARDSON (1986) AND A COMPLETE
      INSTRUMENT DESCRIPTION CAN BE FOUND IN BRIDGE (1977).
 
 
      Processing Level Id            : 5
      Software Flag                  : Y
 
 
    Parameters
    ==========
      Sampling Parameter Name        : TIME
      Data Set Parameter Name        : ION DENSITY
      Sampling Parameter Resolution  : 96.000000
      Sampling Parameter Interval    : 96.000000
      Minimum Available Sampling Int : 96.000000
      Data Set Parameter Unit        : CM-3
      Sampling Parameter Unit        : SECOND
 
 
      Description
      -----------
        A DERIVED PARAMETER EQUALING THE VECTOR MOMENTUM FRAME OR
        VELOCITY FRAME TO WHICH ONE MUST TRANSFORM IN A derived
        parameter equaling the number of ions per unit ION THERMAL
        SPEED: A measure of the velocity associated with ORDER TO
        YIELD ION ANGULAR DISTRIBUTIONS AND-OR the temperature of the
        ions.  It is formally defined as the volume over a specified
        range of ion energy, energy/charge, ELECTRON ANGULAR
        DISTRIBUTIONS THAT ARE ANGULARLY Ion Thermal Speed squared
        equals two times K (Boltzmann's or energy/nucleon.
        Discrimination with regard to mass and or ISOTROPIC AT ALL
        ENERGIES.  SUCH A FRAME CAN BE constant) times T (temperature
        of ion) divided by M (ion charge state is necessary to obtain
        this quantity, however, FOUND ONLY IF OTHER EFFECTS THAT CAN
        YIELD ANGULAR mass).  Each component of a plasma has a
        thermal speed mass and charge state are often assumed due to
        instrument limitations.  associated with it.  ANISOTROPIES
        (E.G.  SPATIAL GRADIENTS) ARE
 
        FACTORED OUT.  THE COMPONENT OF THE TRANSFORM VELOCITY VECTOR
        PERPENDICULAR TO THE LOCAL Many different forms of ion
        density are derived.  Some are MAGNETIC FIELD VECTOR IS
        COUPLED TO THE distinguished by their composition (N+,
        proton, ion, etc.) APPROXIMATELY TIME STATIONARY ELECTRIC
        FIELD.  or their method of derivation (Maxwellian fit, method
        of PARALLEL TO THE LOCAL MAGNETIC FIELD VECTOR A FLOW
        moments).  In some cases, more than one type of density will
        VELOCITY FRAME MAY OR MAY NOT BE A WELL DEFINED be provided
        in a single dataset.  In general, if more than QUANTITY.  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.
 
 
    Source Instrument Parameters
    ============================
      Instrument Host ID              : VG1
      Data Set Parameter Name         : ION DENSITY
      Instrument Parameter Name       : ION RATE
      Important Instrument Parameters : 1
 
      Instrument Host ID              : VG1
      Data Set Parameter Name         : ION DENSITY
      Instrument Parameter Name       : ION CURRENT
      Important Instrument Parameters : 1
 
      Instrument Host ID              : VG1
      Data Set Parameter Name         : ION THERMAL SPEED
      Instrument Parameter Name       : ION RATE
      Important Instrument Parameters : 1
 
      Instrument Host ID              : VG1
      Data Set Parameter Name         : PLASMA VELOCITY
      Instrument Parameter Name       : ION CURRENT
      Important Instrument Parameters : 1
 
      Instrument Host ID              : VG1
      Data Set Parameter Name         : ION THERMAL SPEED
      Instrument Parameter Name       : ION CURRENT
      Important Instrument Parameters : 1
 
      Instrument Host ID              : VG1
      Data Set Parameter Name         : ION DENSITY
      Instrument Parameter Name       : PARTICLE MULTIPLE PARAMETERS
      Important Instrument Parameters : 1
 
 
    Processing
    ==========
 
      Processing History
      ------------------
        Source Data Set ID          : VG1-PLS
        Software                    : MJSANL
        Product Data Set ID         : VG1-S-PLS-5-ION-FBR-96.0SEC
 
 
      Software 'MJSANL'
      -----------------
        Software Name               : MJSANL
        Software Type               : PIN
        Software Release Date       : N/A
        Node ID                     : N/A
        Cognizant Engineer          : N/A
        Software Access Description : N/A
DATA_SET_RELEASE_DATE 1988-08-01T00:00:00.000Z
START_TIME 1980-11-12T08:47:23.550Z
STOP_TIME 1980-11-13T05:46:35.556Z
MISSION_NAME VOYAGER
MISSION_START_DATE 1972-07-01T12:00:00.000Z
MISSION_STOP_DATE N/A (ongoing)
TARGET_NAME SATURN
TARGET_TYPE PLANET
INSTRUMENT_HOST_ID VG1
INSTRUMENT_NAME PLASMA SCIENCE EXPERIMENT
INSTRUMENT_ID PLS
INSTRUMENT_TYPE PLASMA ANALYZER
NODE_NAME Planetary Plasma Interactions
ARCHIVE_STATUS ARCHIVED
CONFIDENCE_LEVEL_NOTE
Overview
    ========
      THIS DATA SET PROVIDES AN ESTIMATE OF THE ION PARAMETERS IN THE
      PLS ENERGY RANGE (10-5950 EV).  FORMAL 1 SIGMA UNCERTAINTIES
      FOR THE DERIVED VELOCITIES, DENSITIES, AND THERMAL SPEEDS ARE
      GIVEN IN THE COMPLETE DATA SET AND RANGE FROM A FEW TO 100%.
      SYSTEMATIC ERRORS MAY RESULT FROM THE USE OF ISOTROPIC
      MAXWELLIAN DISTRIBUTIONS TO MODEL THE IONS.  THIS RESULTS IN AN
      UNDERESTIMATE OF THE TOTAL ION DENSITY AND ION THERMAL SPEED OF
      LESS THAN 20%, BUT HAS LITTLE EFFECT (FEW PERCENT) ON THE
      VELOCITY DETERMINATION.  ONLY CURRENT SPECTRA WITH AT LEAST ONE
      DISTINCT PEAK WERE FIT; THIS GIVES A BIASED SELECTION OF THE
      DATA, PARTICULARLY OUTSIDE L=10 WHERE THE DATA GIVEN IS NOT
      REPRESENTATIVE OF 'AVERAGE' PLASMA CONDITIONS.  SEE RICHARDSON
      (1986) FOR DETAILS.
CITATION_DESCRIPTION Citation TBD
ABSTRACT_TEXT THIS DATA SET CONTAINS THE ION DENSITIES, TEMPERATURES, AND VELOCITIES OBTAINED FROM VOYAGER 1 PLS DATA (VOLTAGE RANGE 10-5950 EV/Q) AT SATURN BY FITTING THE MEASURED SPECTRA WITH ISOTROPIC MAXWELLIAN DISTRIBUTIONS. IT IS A SUBSET OF THE DATA SET VG1-S-PLS-5-ION-FIT-96.0SEC WHICH SHOULD BE OBTAINED BEFORE THIS DATA IS USED. ONLY SPECTRA WHICH HAD DISTINCT CURRENT PEAKS WERE FIT. SPECTRA WERE FIT USING ONE OR TWO ION SPECIES, PROTONS AND/OR A HEAVY ION WHICH WAS TAKEN TO BE OXYGEN. OUTSIDE L=10-12 ION SPECTRA CHANGE RAPIDLY, SO THE VALUES IN THIS DATA SET DO NOT REPRESENT AVERAGE PLASMA CONDITIONS IN THE OUTER MAGNETOSPHERE. A COMPLETE DESCRIPTION OF THIS DATA SET IS GIVEN IN RICHARDSON (1986). DATA FORMAT: FIRST 5 COLUMNS ARE TIME TAG (YEAR, DAY, HOUR, MIN SEC.MSEC), FOLLOWED BY PROTON DENSITY (CM-3), PROTON TEMPERATURE (EV), HEAVY ION DENSITY (CM-3), HEAVY ION TEMPERATURE (EV), AND THREE VELOCITY COMPONENTS, (RHO, PHI,Z) IN KM/S. A CYLINDRICAL COORDINATE SYSTEM CENTERED ON THE PLANET IS USED, WITH RHO OUTWARDS FROM THE SPIN AXIS, PHI IN THE DIRECTION OF ROTATION, AND Z THE DISTANCE ABOVE THE EQUATOR. EACH ROW HAS THE FORMAT (2I4,2I3,F7.3,7E11.3). VALUES OF 1.E32 INDICATE THAT THE PARAMETER COULD NOT BE OBTAINED FROM THE DATA USING THE STANDARD ANALYSIS TECHNIQUE. ADDITIONAL INFORMATION ABOUT THIS DATASET AND THE INSTRUMENT WHICH PRODUCED IT CAN BE FOUND ELSEWHERE IN THIS CATALOG. AN OVERVIEW OF THE DATA IN THIS DATA SET CAN BE FOUND IN RICHARDSON (1986) AND A COMPLETE INSTRUMENT DESCRIPTION CAN BE FOUND IN BRIDGE (1977).
PRODUCER_FULL_NAME JOHN D. RICHARDSON
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