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/************************ CRS Instrument Template *****************************/
/* MODIFICATION                                                               */
/* 920806  JPLPDS::RMONARREZ                                             */
/*         received by mail                                                   */
/* 92-08 EFRIED                                                        */
/*      920916  EFRIED                                                        */
/*         last changes made                                                  */

/* Template: Spacecraft Instrument Template                     Rev: 19890121 */
/* Note:       The following templates form part of a standard                */
/*             set for the submission of a spacecraft instrument              */
/*             to the PDS.                                                    */
/* Hierarchy:   SCINSTRUMENT                                                  */
/*                 INSTINFO                                                   */
/*                 INSTDETECT                                                 */
/*                 INSTELEC                                                   */
/*                 INSTFILTER                                                 */
/*                 INSTOPTICS                                                 */
/*                 SCINSTOFFSET                                               */
/*                 INSTSECTION                                                */
/*                    INSTSECTINFO                                            */
/*                       INSTSECTFOVS                                         */
/*                    INSTSECTPARM                                            */
/*                    INSTSECTDET                                             */
/*                    INSTSECTELEC                                            */
/*                    INSTSECTFILT                                            */
/*                    INSTSECTOPTC                                            */
/*                 INSTMODEINFO                                               */
/*                    INSTMODESECT                                            */
/*                 INSTREFINFO                                                */
/*                    REFERENCE                                               */
/*                       REFAUTHORS                                           */

OBJECT                                      = SCINSTRUMENT          
  SPACECRAFT_ID                                = VG2              
  INSTRUMENT_ID                                = CRS             

  OBJECT                                       = INSTINFO          
    INSTRUMENT_NAME                              = "COSMIC RAY SYSTEM"
    INSTRUMENT_TYPE                              = "CHARGED PARTICLE ANALYZER"
    PI_PDS_USER_ID                               = ESTONE
    NAIF_DATA_SET_ID                             = "N/A"
    BUILD_DATE                                   = 1976
    INSTRUMENT_MASS                              = 7    
    INSTRUMENT_HEIGHT                            = 0.177
    INSTRUMENT_LENGTH                            = 0.286
    INSTRUMENT_WIDTH                             = 0.203
    INSTRUMENT_MANUFACTURER_NAME                 = SPACETAC
    INSTRUMENT_SERIAL_NUMBER                     = FU2     
    INSTRUMENT_DESC                              = "
The Voyager cosmic ray experiment (CRS) measures charged
particles in charge, mass and energy intervals summarized
as follows: (i) Nuclei charge and energy spectra: Z = 1-30,
energy range 1-500 MeV for H to 2.5-500 MeVuc for Fe.
(ii)Isotopes: Z = 1-8 (delta M = 1), energy range
2-75 MeVuc.  (iii) Electrons: 3-110 MeV
(iv) Anisotropies:  All components ranging from H (1-150)
to Fe (2.7-500 MeVuc) as well as 3-110 MeV electrons.
CRS has three detector systems containing a total of seven
particle telescopes consisting entirely of solid-state
charged-particle detectors.  The detector systems are:
the High Energy Telescope System (HETS), consisting of
two double ended telescopes each containing eight detectors;
the Low Energy Telescope System (LETS), consisting of
four telescopes with four detectors each; and the
Electron Telescope (TET), with eight detectors.
The combination of these telescope systems achieve the
measurements described above through multi-parameter
analysis of individual particle events.  The analyzed
events occur at a rate of a few per second, and consist
of pulse height information from three detectors or
combinations of detectors.  More detailed information
can be found in Stone et al., Space Science Reviews, 1977,
and Stilwell et al., IEEE Transactions on Nuclear Science,
1979.  In addition to the event analysis, each detector,
and various combinations of detectors in
coincidence/anti-coincidence, have counting-rate data
for all events occurring in that detector (or combination)
satisfying certain electronic requirements (the pulses
should be above a certain energy threshold and
sufficiently spaced in time for discrimination).
The counting-rate data generally have an associated
geometry factor and energy interval (or lower energy
threshold), which can be used to calculate fluxes of
the relevant particle species in that energy interval.
However, these are often ill-defined because of the
varying thickness of passive shielding material
which must be penetrated by particles reaching
individual detectors.  It is therefore essential to
consider the sensitivity to particles of different species
and of different energy intervals when interpreting the
counting-rate data.  Also, during times of high particle
flux, it is sometimes necessary to correct the counting
rates for non-linear detector response due to deadtime,
for pulse pile-up and for discriminator baseline shifts."
    SCIENTIFIC_OBJECTIVES_SUMMARY                = "
To provide measurements of the cosmic ray flux and energy
spectra during the cruise phase of the Voyager mission,
and of the trapped, energetic particles during planetary
encounters.  The planetary data are used to study the
dynamics of the radiation belts in each magnetosphere,
including the source, loss, transport and energization
mechanisms, elemental composition and satellite/ring
interactions."
    INSTRUMENT_CALIBRATION_DESC                  = "
Laboratory calibrations of the individual detectors
and the complete telescopes have been made with
particle accelerators and radioactive sources.
A calibration file for the electron telescope is
included in PDS (see the DATA_SET_OR_INST_PARM_DESC).
The calibrations of the electron telescope,
which need to be considered in the data analysis,
are described in internal reports at CalTech.
Copies of these documents can be obtained from
the experimental representatives."
    OPERATIONAL_CONSID_DESC                      = "
The instrument operates continuously sampling data
over uniform accumulation intervals.  The accumulation
intervals vary for the different rate numbers, of which
there are 135 consisting of the individual detector
and multiple detector counting rates being used in a
particular instrument mode.  They are always multiples
of six seconds and are sampled in a sequence which
repeats every 96 seconds, with some rates being sampled
continuously over each 96 second period, and some
(including all of the single detector rates) only with
a single six second sample each 96 seconds.  The
mode, which determines the various combinations of
detectors that are included in the multiple detector
measurements, is commandable by the spacecraft and
during planetary encounters is usually set to a mode
which provides good data return for high flux
environments."
  END_OBJECT                                   = INSTINFO     

  OBJECT                                       = INSTDETECT 
    DETECTOR_ID                                  = CRS      
    DETECTOR_TYPE                                = "SOLID STATE"
    DETECTOR_ASPECT_RATIO                        = "N/A"
    MINIMUM_WAVELENGTH                           = "N/A"       
    MAXIMUM_WAVELENGTH                           = "N/A"      
    NOMINAL_OPERATING_TEMPERATURE                = 273
    DETECTOR_DESC                                = "
The Cosmic Ray System (CRS) instrument contains 40 solid-state silicon
detectors that are used individually and in
combinations (using coincidence and anti-coincidence
criteria) to detect and characterize charged
particles.  The detector effective thicknesses range from
35 microns to 6 mm to cover a broad range of particle
energy and mass characteristics."
    SENSITIVITY_DESC                             = "
In the case of nuclear particles, detectors count
the particles that have energy deposits which exceed
the detectors individual threshold with an efficiency
that approaches 1.  Therefore the sensitivity is strictly
a function of the geometry factors of the detectors and
their energy and species band widths (these are documented
elsewhere in this catalog).  The geometry factors have
units of area times steradians (cm**2 sr).  In the case of
electrons, the detector efficiencies are less than 1,
leading to energy and direction dependent effective
geometry factors which are determined by laboratory
calibration.  Tables of these geometry factors
are included in this catalog, and need to be unfolded
from the electron counting rates to determine the
absolute flux levels."
  END_OBJECT                                   = INSTDETECT   
 
  OBJECT                                       = INSTELEC 
    ELECTRONICS_ID                               = CRS  
    ELECTRONICS_DESC                             = "
Timed accumulations of particle counts satisfying
various analog pulse-height discrimination levels
and simultaneous analog pulse-height discriminations
for multiple detectors.  Pulse-height analog-to-digital
conversions from multiple, simultaneous detectors for
direct telemetry.  For details see Stilwell et al.,
IEEE Transactions on Nuclear Science, 1979."
  END_OBJECT                                   = INSTELEC     

  OBJECT                                       = INSTFILTER
    FILTER_NUMBER                                = "N/A"
    FILTER_NAME                                  = "N/A"
    FILTER_TYPE                                  = "N/A"
    MINIMUM_WAVELENGTH                           = "N/A"
    CENTER_FILTER_WAVELENGTH                     = "N/A"
    MAXIMUM_WAVELENGTH                           = "N/A"
    MEASUREMENT_WAVE_CALBRT_DESC                 = "N/A"
  END_OBJECT                                   = INSTFILTER   

  OBJECT                                       = INSTOPTICS
    TELESCOPE_ID                                 = "N/A"
    TELESCOPE_FOCAL_LENGTH                       = "N/A"
    TELESCOPE_DIAMETER                           = "N/A"
    TELESCOPE_F_NUMBER                           = "N/A"
    TELESCOPE_RESOLUTION                         = "N/A"
    TELESCOPE_TRANSMITTANCE                      = "N/A"
    TELESCOPE_T_NUMBER                           = "N/A"
    TELESCOPE_T_NUMBER_ERROR                     = "N/A"
    TELESCOPE_SERIAL_NUMBER                      = "N/A"
    OPTICS_DESC                                  = "N/A"
  END_OBJECT                                   = INSTOPTICS   

  OBJECT                                       = SCINSTOFFSET
    PLATFORM_OR_MOUNTING_NAME                    = "SCIENCE BOOM"
    CONE_OFFSET_ANGLE                            = "N/A"
    CROSS_CONE_OFFSET_ANGLE                      = "N/A"
    TWIST_OFFSET_ANGLE                           = "N/A"
    INSTRUMENT_MOUNTING_DESC                     = "
The Cosmic Ray System (CRS) instrument is mounted about 
half way along the science boom on the side of the 
high-gain antenna, so as to provide an unobstructed 
nominal field of view for each of the particle telescopes.  
The nominal unit vectors of each of the telescope bore sights
relative to the spacecraft fixed coordinate system
are as follows: 
 LETA            .9063078,       0.0,  .4226183
 LETB            .2862054,  .7455905, -.6018150
 LETC           -.9063078,       0.0, -.4226183
 LETD            .3150813, -.6665596, -.6755902
 HET1           -.7263100,  .4716712,  .5000000
 HET2(Voyager1) -.6617401, -.7096294,  .2419219
 HET2(Voyager2) -.9372337,  .2511310,  .2419219"
  END_OBJECT                                   = SCINSTOFFSET 

  OBJECT                                       = INSTSECTION   
    SECTION_ID                                   = CRS       

    OBJECT                                       = INSTSECTINFO
      SCAN_MODE_ID                                 = "N/A"
      DATA_RATE                                    = "N/A"
      SAMPLE_BITS                                  = 12
      TOTAL_FOVS                                   = "N/A"

      OBJECT                                       = INSTSECTFOVS
        FOV_SHAPE_NAME                               = "N/A"
        HORIZONTAL_PIXEL_FOV                         = "N/A"
        VERTICAL_PIXEL_FOV                           = "N/A"
        HORIZONTAL_FOV                               = "N/A"
        VERTICAL_FOV                                 = "N/A"
        FOVS                                         = "N/A" 
      END_OBJECT                                   = INSTSECTFOVS 
    END_OBJECT                                   = INSTSECTINFO 

    OBJECT                                       = INSTSECTPARM
      INSTRUMENT_PARAMETER_NAME                    = "D1 RATE"
      MINIMUM_INSTRUMENT_PARAMETER                 = "N/A"
      MAXIMUM_INSTRUMENT_PARAMETER                 = "N/A"
      NOISE_LEVEL                                  = "N/A"
      INSTRUMENT_PARAMETER_UNIT                    = "COUNTS/SECOND"
      SAMPLING_PARAMETER_NAME                      = TIME
      MINIMUM_SAMPLING_PARAMETER                   = "N/A"
      MAXIMUM_SAMPLING_PARAMETER                   = "N/A"
      SAMPLING_PARAMETER_INTERVAL                  = 96.0
      SAMPLING_PARAMETER_RESOLUTION                = 6.0
      SAMPLING_PARAMETER_UNIT                      = SECOND      
    END_OBJECT                                   = INSTSECTPARM
 
    OBJECT                                       = INSTSECTPARM
      INSTRUMENT_PARAMETER_NAME                    = "D2 RATE"
      MINIMUM_INSTRUMENT_PARAMETER                 = "N/A"
      MAXIMUM_INSTRUMENT_PARAMETER                 = "N/A"
      NOISE_LEVEL                                  = "N/A"
      INSTRUMENT_PARAMETER_UNIT                    = "COUNTS/SECOND"
      SAMPLING_PARAMETER_NAME                      = TIME
      MINIMUM_SAMPLING_PARAMETER                   = "N/A"
      MAXIMUM_SAMPLING_PARAMETER                   = "N/A"
      SAMPLING_PARAMETER_INTERVAL                  = 96.0
      SAMPLING_PARAMETER_RESOLUTION                = 6.0
      SAMPLING_PARAMETER_UNIT                      = SECOND      
    END_OBJECT                                   = INSTSECTPARM 

    OBJECT                                       = INSTSECTPARM
      INSTRUMENT_PARAMETER_NAME                    = "D1 RATE"
      MINIMUM_INSTRUMENT_PARAMETER                 = "N/A"
      MAXIMUM_INSTRUMENT_PARAMETER                 = "N/A"
      NOISE_LEVEL                                  = "N/A"
      INSTRUMENT_PARAMETER_UNIT                    = "COUNTS/SECOND"
      SAMPLING_PARAMETER_NAME                      = TIME
      MINIMUM_SAMPLING_PARAMETER                   = "N/A"  
      MAXIMUM_SAMPLING_PARAMETER                   = "N/A"
      SAMPLING_PARAMETER_INTERVAL                  = 6.0 
      SAMPLING_PARAMETER_RESOLUTION                = 6.0
      SAMPLING_PARAMETER_UNIT                      = SECOND
    END_OBJECT                                   = INSTSECTPARM

    OBJECT                                       = INSTSECTDET 
      DETECTOR_ID                                  = CRS   
    END_OBJECT                                   = INSTSECTDET  

    OBJECT                                       = INSTSECTELEC
      ELECTRONICS_ID                               = CRS      
    END_OBJECT                                   = INSTSECTELEC 
 
    OBJECT                                       = INSTSECTFILT
      FILTER_NUMBER                                = "N/A"
    END_OBJECT                                   = INSTSECTFILT 

    OBJECT                                       = INSTSECTOPTC
      TELESCOPE_ID                                 = "N/A"  
    END_OBJECT                                   = INSTSECTOPTC 
  END_OBJECT                                   = INSTSECTION  

  OBJECT                                       = INSTMODEINFO
    INSTRUMENT_MODE_ID                           = ENCOUNTER
    GAIN_MODE_ID                                 = "N/A"             
    DATA_PATH_TYPE                               = REALTIME
    INSTRUMENT_POWER_CONSUMPTION                 = 5.0                 
    INSTRUMENT_MODE_DESC                         = "
During the planetary encounters the instrument is placed in a modes designed
to optimize the data return in high particle flux environments.  These involve
adjustments to the multiple detector confidence requirements and do not
effect the single detector rates.  Detailed knowledge of the instrument modes
is not required to understand the data provided in this catalog."

    OBJECT                                       = INSTMODESECT         
      SECTION_ID                                   = CRS              
    END_OBJECT                                   = INSTMODESECT 
  END_OBJECT                                   = INSTMODEINFO

/*                             */
/*  Repeat for "Playback Data" */
/*                             */

  OBJECT                                       = INSTMODEINFO
    INSTRUMENT_MODE_ID                           = ENCOUNTER
    GAIN_MODE_ID                                 = "N/A"             
    DATA_PATH_TYPE                               = "RECORDED DATA PLAYBACK"  
    INSTRUMENT_POWER_CONSUMPTION                 = 5.0                 
    INSTRUMENT_MODE_DESC                         = "
During the planetary encounters the instrument is placed in a modes designed
to optimize the data return in high particle flux environments.  These involve
adjustments to the multiple detector confidence requirements and do not
effect the single detector rates.  Detailed knowledge of the instrument modes
is not required to understand the data provided in this catalog."

    OBJECT                                       = INSTMODESECT         
      SECTION_ID                                   = CRS              
    END_OBJECT                                   = INSTMODESECT 
  END_OBJECT                                   = INSTMODEINFO

/*                    */
/*  End repeated info */
/*                    */

  OBJECT                                       = INSTREFINFO
    REFERENCE_KEY_ID                             = "STONEETAL1977"

    OBJECT                                       = REFERENCE      
      DOCUMENT_TOPIC_TYPE                          = "CRS DOCUMENTATION"
      JOURNAL_NAME                                 = "SPACE SCIENCE REVIEWS"
      PUBLICATION_DATE                             = 1977-12-01
      REFERENCE_DESC                               = "
           Scientific goals and operating characteristics of the CRS instrument"
      OBJECT                                       = REFAUTHORS   
        AUTHOR_FULL_NAME                             = "E.C. STONE"
      END_OBJECT                                   = REFAUTHORS   
    END_OBJECT                                   = REFERENCE    
  END_OBJECT                                   = INSTREFINFO
  
  OBJECT                                       = INSTREFINFO       
    REFERENCE_KEY_ID                             = "STILWELLETAL1979"

    OBJECT                                       = REFERENCE       
      DOCUMENT_TOPIC_TYPE                          = "CRS DOCUMENTATION"
      JOURNAL_NAME                                 = "IEEE TRANSACTIONS ON 
                                                      NUCLEAR SCIENCE"
      PUBLICATION_DATE                             = 1979
      REFERENCE_DESC                               = "    
                       CRS operating characteristics, especially of electronics"
      OBJECT                                       = REFAUTHORS    
        AUTHOR_FULL_NAME                             = "D.E. STILWELL"
      END_OBJECT                                   = REFAUTHORS   
    END_OBJECT                                   = REFERENCE    
  END_OBJECT                                   = INSTREFINFO  
END_OBJECT                                   = SCINSTRUMENT