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
|
SEARCH/ACCESS DATA |
Planetary Plasma Interactions Website
|
|