Data Set Overview
        =================
          THIS DATA SET CONTAINS ESTIMATES OF THE ION MOMENT DENSITY IN
          THE PLS VOLTAGE RANGE (10-5950 EV/Q) AT SATURN DURING THE
          VOYAGER 1 ENCOUNTER.  RIGID COROTATION IS ASSUMED, WHICH LEADS
          TO AN UNDERESTIMATE OF THE DENSITY IN SOME REGIONS, AS DOES THE
          USE OF AN ACCEPTANCE AREA RELEVANT FOR A COLD BEAM FOR PLASMA
          WHICH IS TRANSONIC IN SOME REGIONS.  DENSITIES MAY BE
          UNDERESTIMATED BY A FACTOR OF 2-3 IN THE INNER MAGNETOSPHERE,
          SO THIS DATA SET SHOULD BE USED PRIMARILY FOR STUDIES USING
          VARIATIONS IN PLASMA DENSITY.  THE FIT DENSITIES GIVE A BETTER
          ESTIMATE OF THE ABSOLUTE DENSITY.  THIS IS THE DATA SHOWN AND
          DESCRIBED IN DETAIL IN LAZARUS AND MCNUTT (1983).

          DATA FORMATS ARE DESCRIBED AS BELOW:
          ================================================================
          name      type       description
          ----------------------------------------------------------------
          time      A24        time in the format yyyy-mm-ddThh:mm:ss.sssZ
          ion_mden  1PE9.2     total ion moment (cnts/cm**3)

          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 LAZARUS AND
          MCNUTT (1983) 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 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.


        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 DENSITY
          Instrument Parameter Name       : PARTICLE MULTIPLE PARAMETERS
          Important Instrument Parameters : 1


        Processing
        ==========

          Processing History
          ------------------
            Source Data Set ID          : VG1-PLS
            Software                    : MOMANAL
            Product Data Set ID         : VG1-S-PLS-5-ION-MOM-96.0SEC


          Software 'MOMANAL'
          ------------------
            Software Name               : MOMANAL
            Software Type               : PIN
            Software Release Date       : N/A
            Node ID                     : N/A
            Cognizant Engineer          : N/A
            Software Access Description : N/A

          Product Data Set ID         : VG1-S-PLS-5-ION-MOM-96.0SEC


          Software 'MOMANAL'
          ------------------
          Software Name               : MOMANAL
          Software Type               : PIN
          Software Release Date       : N/A
          Node ID                     : N/A
          Cognizant Engineer          : N/A
          Software Access Description : N/A

Confidence Level:
   ===================

          THIS DATA SET PROVIDES AN ESTIMATE OF THE POSITIVE ION CHARGE
          DENSITY.  SEVERAL ASSUMPTION/SIMPLIFICATIONS ARE MADE TO
          SIMPLIFY THE ANALYSIS WHICH MAY AFFECT THE ACCURACY OF THE
          RESULTS.  HIGH MACH NUMBER FLOW IS ASSUMED; MACH NUMBERS OF 1,
          WHICH ARE OBSERVED IN THE INNER MAGNETOSPHERE, CAN RESULT IN
          50% UNDERESTIMATES OF THE CHARGE DENSITY.  THE ANALYSIS ASSUMES
          A UNIT RESPONSE (IE., ALL PARTICLES IN A COLD BEAM INCIDENT ON
          THE APERTURE OF THE EXPERIMENT WOULD BE MEASURED AT THE
          COLLECTOR).  THE ACTUAL RESPONSE IS AS LOW AS 70%.  A VELOCITY
          INTO THE DETECTOR MUST ALSO BE ASSUMED; THE VELOCITY USED IS
          THE COROTATION VELOCITY.  OBSERVATIONS INDICATE THAT IN SOME
          REGIONS THE ACTUAL VELOCITY IS AS LITTLE AS HALF OF THE
          COROTATION VELOCITY, GIVING FACTOR OF 2 ERRORS IN THE DENSITY.
          FINALLY, ONLY IONS IN THE PLS ENERGY RANGE (10-5950 EV/Q) ARE
          COUNTED.  THE CUMULATIVE ERROR FROM ALL THESE EFFECTS IS LESS
          THAN 10% IN THE SOLAR WIND, LESS THAN 30% IN THE OUTER
          MAGNETOSPHERE (R>10 RS), AND UP TO A FACTOR OF 3 INSIDE THIS.
          SINCE THE AMPLITUDE OF EACH OF THESE EFFECTS VARIES SLOWLY IN
          TIME (DISTANCE), THE RELATIVE CHANGES IN DENSITY ARE GOOD TO 10
          PERCENT IN MOST CASES.  THIS DATA SET IS MOST USEFUL FOR
          LOOKING AT DENSITY VARIATIONS; ION FIT DENSITIES ARE MUCH
          BETTER INDICATORS OF THE ABSOLUTE PLASMA DENSITY


    Data Coverage
    ==================
    Filename Records Start                     Stop
    ---------------------------------------------------------------------
    Volume ID: VG_1601
    ION_MOM.TAB  1125  1980-11-12T03:00:11.000Z  1980-11-13T08:58:35.000Z

    Missing Data Flag
    ==================
    Any data column whose value is  -9.99e+10 is a missing data value.