Document title: VOLDESC.SFD for NDADS DE HAPI SATM data
Project: DE
NDADS Datatype: HAPI  
Super-EID: DOCUMENT                      
There may be other documents also identified by this super-EID.
NDADS filename: HAPI_VOLDESC.SFD
TRF entry: B46591.txt in NSSDC's controlled digital document library, Feb. 1998.
Document text follows:
----------------------

CCSD3ZF0000100000001CCSD3VS00002MRK**001

LOG_VOL_IDENT: USANASANSSDDEA5-0001C
LOG_VOL_INITIATION_DATE: 1992-12-03
LOG_VOL_CLOSING_DATE: YYYY-MM-DD
LOG_VOL_CAPACITY: 1 GB/LOGICAL_VOL
LOG_VOL_FILE_STRUCTURE: FILES-11

VOLUME_DIAMETER: 12 INCHES
VOLUME_DRIVE_MFGR_AND_MODEL: OPTIMUM 1000 WITH 1.6 CONTROLLER

COMPUTER_MANUFACTURER: DIGITAL EQUIPMENT CORPORATION
OPERATING_SYSTEM: MICROVMS 5.4
COMPUTER_SYSTEM: MICRO VAX II
TRANSFER_SOFTWARE: SOAR 4.2

TECHNICAL_CONTACTS:   ROBERT M. CANDEY
                      NASA/GSFC CODE 632
                      GREENBELT, MD 20771
                      PHONE:  1-301-286-6707
                      SPAN:  NCF::CANDEY
                      INTERNET: ROBERT.M.CANDEY.1@GSFC.NASA.GOV

PREV_LOG_VOLS: USANASANSSDDEA5-0001A
               USANASANSSDDEA5-0001B

CCSD$$MARKERMRK**001CCSD3SS00002MRK**002

DATA_SET_NAME: HAPI SATM file.  (SATM = Stand Alone Telemetry)
DATA_SOURCES: DYNAMICS EXPLORER A, HIGH ALTITUDE PLASMA INSTRUMENT (HAPI)

SCIENTIFIC_CONTACTS: DR. J. L. BURCH             /        DR. R. A. HOFFMAN
                     DEPT. OF SPACE SCIENCES              CODE 696
                     SOUTHWEST RESEARCH INST.             NASA/GSFC
                     P.O. DRAWER 28510                    GREENBELT, MD 20771
                     SAN ANTONIO, TX 78284                PHONE: 301-286-7386
                                                          SPAN DE696::U6RAH

SOURCE_CHARACTERISTICS:

  A. DESCRIPTION_OF_SPACECRAFT:
  The Dynamics Explorer 1 spacecraft was one of two satellites launched for
  the Dynamics Explorer program.  The two spacecraft were launched together
  into coplanar polar orbits for the purpose of studying coupling between the
  magnetosphere, ionosphere, and the atmosphere.  The DE-1 spacecraft was
  placed in a highly elliptical orbit whereas the DE-2 spacecraft had an orbit
  with low ellipticity.
  Instruments aboard the DE-1 spacecraft were: magnetometer (MAGA), plasma wave
  instrument (PWI), spin-scan auroral imager (SAI), retarding ion mass
  spectrometer (RIMS), high-altitude plasma instrument (HAPI), and hot plasma
  composition instrument (EICS - energetic ion composition spectrometer).

  B. ORBIT_INFORMATION:
  Because the Delta launch vehicle did not complete a full burn, the DE-1
  satellite was placed in a lower than anticipated polar orbit, initially
  23173 by 570 km.  The orbital period was 409 min.  The DE-1 and DE-2 satel-
  lites were launched by the same vehicle so that their orbits would be
  coplanar, allowing occasional two-point measurements along magnetic field
  lines. The DE-1 spacecraft spun at a rate of 10 rpm and the spin axis was
  perpendicular to the orbital plane.   The apogee latitude precessed through
  360 degrees in 3 years.  The apogee was positioned over the north pole on
  September 8, 1981.

  C. PERFORMANCE:
  The DE-1 spacecraft performed well through its lifetime. The launch was on
  Aug. 3, 1981 and the satellite ceased science operations on Feb. 26, 1991.
  Power limitations forced the duty cycle to be limited such that the
  instruments were not on continuously.  The initial average duty cycle was over
  90%, but this decreased over the lifetime to about 20% at the end of life.

INVESTIGATION_OBJECTIVES:
  The objectives of the High Altitude Plasma investigation are to contribute to
  the Dynamics Explorer mission goals to provide high-resolution phase-space
  measurements of electrons and positive ions over the energy range from 5 eV
  to 32 keV.  These measurements, along with supporting measurements from other
  instruments on DE-A and DE-B, primarily address the identification of the
  charge carriers of Birkeland currents by the high-latitude plasma populations,
  the transport of plasma through the mid-altitude cusp and into the polar cap,
  the upward mass flow from the ionosphere into the hot plasma population of the
  magnetosphere, and resonant interactions between hot plasma and natural and
  artificially-injected plasma waves and electromagnetic waves. ( Refer to
  J. L. Burch et. al., Space Science Instrumentation Vol. 5, No. 4, 1981,
  pp. 455-456).

INSTRUMENT_ATTRIBUTES:

  A. DESCRIPTION_OF_INSTRUMENT:
  The High Altitude Plasma Instrument (HAPI) consisted of an array of 5
  parabolic electrostatic analyzers lying in a plane containing the spacecraft
  spin axis, and spanning 90 degrees in angle.
  Each parabolic analyzer was followed by two channel electron multipliers to
  measure simultaneously electrons and positive ions.
  The basic mode of operation provided a 32-point energy spectrum every
  one-half second between 5 eV and 32 keV by stepping through 32 sets of
  voltages on the analyzer plates on a logarithmic scale each half second.
  No more than 8 of the 10 sensors were used at one time; typically, 3 electron
  and 5 ion detectors were monitored.  The detectors sampled, sampling rate,
  voltage levels, etc. could be changed on command allowing a large variety of
  modes.

  B. OPERATIONAL_MODE:
  Operation modes were normally selected to emphasize either high angular
  resolution or high temporal (and spatial) resolution.
  1. HIGH_ANGULAR_RESOLUTION_MODE:
     In this mode, the programmable power supply (PPS) was stepped each time a
     nadir pulse was received from the spacecraft.  That is, a single energy was
     sampled every 0.93 degree for an entire spacecraft spin period.  This
     mode was used primarily near apogee for studies of the loss-cone effects
     of wave-particle interactions and for detection of ion beams produced by
     the upward acceleration of ionospheric ions.
  2. HIGH_TEMPORAL_RESOLUTION_MODE:
     In this mode, multiple energy spectra were required during each spacecraft
     spin.  Typically 24 16-point energy spectra, each covering 15 degree of
     spacecraft spin were measured during each spin period.  An increase to 32
     energy steps, covering the full energy range of the instrument, decreased
     the angular resolution to 30 degrees of spacecraft spin.

  C. MEASURED_PARAMETERS:
  Outputs from pulse amplifiers in the detector modules were converted into an
  8-bit compressed telemetry word using a quasi-logarithmic compression scheme.
  A decompression algorithm is used to calculate a decimal count rate, and with
  appropriate geometric factors, accumulation times and detector efficiencies,
  various types of fluxes can be derived as a function of energy.  These fluxes
  are described in the file FORMAT.SFD and include the calculations via
  software provided of the differential number flux, the differential energy
  flux, and the phase space density.
  The distribution function can be derived from the phase space density data by
  contouring the density in velocity space.  Software is not provided for this
  last calculation.

  D. PERFORMANCE_OF_THE_INSTRUMENT:
  The HAPI instrument initially performed very well after the spacecraft was
  launched.  However, no data were received after December 1, 1981 due to high
  voltage power failure.

  E. RESOLUTION:
  Each SATM record contains one DE-1 major telemetry frame (8 seconds) of data.
  The HAPI stepping power supply always provided voltages to the electrostatic
  analyzers at a rate of 64 steps per second.  It had the capability of
  producing a staircase of 64 different steps to cover the energy range from
  5 eV to 32 keV on a logarithmic scale.  However, typically 32 (or 16) of the
  steps were used by skipping some of the steps, allowing two (or four) sweeps
  through the energy range per second.

  PARAMETERS:
  The SATM files contain:  The date and time of the start of each record, the
  number of sensors which were operating, each sensor's ID number, the
  energy step rate, skip rate, start step, and stop step, orbit/attitude
  information, nadir pulse times, magnetic field data, counts from the sensors,
  and energy step numbers.
  ( Refer to Dynamics Explorer-1, HAPI/LAPI Data Processing Software System I.
  High Altitude Plasma Instrument (HAPI), CSC documentation CSC/TM-82/6132,
  Section 2).

  It should be noted that the SATM files do not contain geophysically meaningful
  parameters from the HAPI instrument. Such parameters, as described in (C.
  MEASURED PARAMETERS), are obtained via the software provided which reads the
  SATM files and calculates the parameters.  The magnetic field parameters are
  only used for the calculation of the pitch angles of the detectors.

  DATA_SET_QUALITY:
  There have been few problems with data quality.  There is about a 5% error in
  the calibration.

  DATA_PROCESSING_OVERVIEW:

  A. DATA_PROCESSING_CYCLE:
  The Stand Alone Telemetry (SATM) files were generated directly from DE-1
  Telemetry files stored on optical disks and merged with orbit data from the
  DE Orbit/Attitude database.

  B. HISTORY:
  The original HAPI SATM file database was generated on the DE Sigma-9 computer.
  The Sigma-9 software had problems dealing with time gaps and telemetry errors,
  and produced fragmented files (several files per pass).  Mission Analysis
  Files (MAFs) were also generated on the Sigma-9 and used for analysis and
  plotting.

  In 1992, the HAPI SATM database was regenerated on a microVax computer to
  correct these problems.  Only a few of the old Sigma-9 files are still in
  use where new SATM files could not be generated.  However these have been
  converted to the new SATM format.  These are marked by the letter D in the
  SATM file name. (See NAMING_CONVENTION.)  These SATM files may be incomplete.

  The rest of the old Sigma-9 files, as well as MAFs are no longer in use.
  A new, more efficient file structure was used allowing easier access and
  reducing file size.  See the file FORMAT.SFD for information concerning the
  HAPI SATM files.

DATA_SET_NAME: HAPI STAND-ALONE TELEMETRY FILES (SATM)
DATA_USAGE:
DATA_ORGANIZATION: Are described in FORMAT.SFD .

TIME_SPAN_OF_THE_DATA: 20-AUG-1981 TO 01-DEC-1981

TYPE_OF_FILE_RELATIONSHIP:
All the HAPI instrument data are contained in SATM files.

TIME_GAPS:
There are occasionally time gaps between major frames.  This is due to the fact
that bad major frames were not written to the SATM files.  Care should be taken
in checking for time gaps when analyzing the data.

SOFTWARE_TO_UNPACK_THE_DATA: The utility is included in HLAPI_SOFTWARE.TAR-GZ
that must be uncompressed and untarred (zcat hlapi_software.tar-gz | tar xvf -)
and stored in your local directory.  Instructions on how to use the
software can be found in the file HOW_TO_USE_REDUCE_SATM.TXT in the HAPI 
directory.

SOFTWARE_APPLICATION_SCOPE:  This utility applies to all the data files, i.e.
those that can be named (using wildcards, and "/" to denote directory levels)
/HAPI/8*/*.SATM .

CCSD$$MARKERMRK**002CCSD3KS00002MRK**003

LOG_VOL_COVERAGE: 1981-11-05 TO 1981-12-01

General Note: Inspecting the names of the directories that are subordinate to
the HAPI directory will directly indicate the dates of the data covered in the
given volume.  For example, on the first side (HAPI01) one of the directories
is named:

81228_81257

This means that the data covered in the directory is "from 1981, 228th day
through 1981, 257th day, inclusive."

The three platter-sides are named HAPI01, HAPI02, and HAPI03.  The directories
on the three platter-sides are:

(HAPI01)        (HAPI02)        (HAPI03)
81228_81257    81285_81288      81309_81312
81258_81263    81289_81292      81313_81316
81264_81269    81293_81296      81317_81321
81270_81275    81297_81300      81322_81325
81276_81279    81301_81304      81326_81330
81280_81284    81305_81308      81331_81335

There are two files that list the names/time-coverages/directories of the data
files (*.SATM).  One of these files lists this information for the "current"
platter-side, and the other file lists this for all three platter sides.  The
format of these two lists is the same, and is described in the file
LISTFORM.SFD .

TYPES_OF_DATA_FILES_INCLUDED:  HAPI SATM FILES ONLY

SATM_TIME_COVERAGE:
    1981-11-05T01:30:51 TO 1981-12-01T12:57:37

NAMING_CONVENTION:
  The start day and time are encoded in the HAPI SATM filename. Each HAPI SATM
  filename is in the following format:  'HyrdayhhmmB.SATM'
   H    - indicates a HAPI file ( all files in this dataset are H)
   yr   - the last two digits of the year, i.e., 81 for 1981
   day  - the Julian day (Jan 1 = 001)
   hh   - the starting hour of the file
   mm   - the starting minute of the file
   B    - the production version of the file.  Most files in this data set are 
          B, the few files from the Sigma-9 are D.  Further information may 
          be found in DATA_PROCESSING_OVERVIEW (above), in subsection B,
          "HISTORY".
   SATM - the extension, indicating it is a Stand Alone Telemetry file

  For example:  H812820506B.SATM would be a HAPI SATM file which started at 
  5:06 on Julian day 282 in 1981.

FILE_TIME_COVERAGE:
See LOG_VOL_COVERAGE, above, and
See NAMING_CONVENTION, above, and
See file THIS_SIDE_.DATA_FILE_LIST, and
See file ALL_3_SIDES.DATA_FILE_LIST.

OTHER_LOG_VOL_COVERAGE:
       1981-08-16 TO 1981-10-11
       1981-10-12 TO 1981-11-04

CCSD$$MARKERMRK**003CCSD3RF0000300000001

REFERENCETYPE=$CCSDS2;

LABEL=ATTACHED;
REFERENCE="/HAPI/FORMAT.SFD";
REFERENCE="/HAPI/LISTFORM.SFD";

LABEL=CCSD3SF0000200000001;
REFERENCE="/HAPI/HLAPI_SOFTWARE.TAR-GZ-*";
REFERENCE="/HAPI/HOW_TO_USE_REDUCE_SATM.TXT-*";

LABEL=NSSD3IF0018400000001;
REFERENCE="/HAPI/81309_81312/*.SATM-*";
REFERENCE="/HAPI/81313_81316/*.SATM-*";
REFERENCE="/HAPI/81317_81321/*.SATM-*";
REFERENCE="/HAPI/81322_81325/*.SATM-*";
REFERENCE="/HAPI/81326_81330/*.SATM-*";
REFERENCE="/HAPI/81331_81335/*.SATM-*";

LABEL=NSSD3KF0012900000001;
REFERENCE="/HAPI/THIS_SIDE.DATA_FILE_LIST-*";
REFERENCE="/HAPI/ALL_3_SIDES.DATA_FILE_LIST-*";

/* (EOF) */
CCSD3ZF0000100000001CCSD3VS00002MRK**001

LOG_VOL_IDENT: USANASANSSDDEA5-0001C
LOG_VOL_INITIATION_DATE: 1992-12-03
LOG_VOL_CLOSING_DATE: YYYY-MM-DD
LOG_VOL_CAPACITY: 1 GB/LOGICAL_VOL
LOG_VOL_FILE_STRUCTURE: FILES-11

VOLUME_DIAMETER: 12 INCHES
VOLUME_DRIVE_MFGR_AND_MODEL: OPTIMUM 1000 WITH 1.6 CONTROLLER

COMPUTER_MANUFACTURER: DIGITAL EQUIPMENT CORPORATION
OPERATING_SYSTEM: MICROVMS 5.4
COMPUTER_SYSTEM: MICRO VAX II
TRANSFER_SOFTWARE: SOAR 4.2

TECHNICAL_CONTACTS:   ROBERT M. CANDEY
                      NASA/GSFC CODE 632
                      GREENBELT, MD 20771
                      PHONE:  1-301-286-6707
                      SPAN:  NCF::CANDEY
                      INTERNET: ROBERT.M.CANDEY.1@GSFC.NASA.GOV

PREV_LOG_VOLS: USANASANSSDDEA5-0001A
               USANASANSSDDEA5-0001B

CCSD$$MARKERMRK**001CCSD3SS00002MRK**002

DATA_SET_NAME: HAPI SATM file.  (SATM = Stand Alone Telemetry)
DATA_SOURCES: DYNAMICS EXPLORER A, HIGH ALTITUDE PLASMA INSTRUMENT (HAPI)

SCIENTIFIC_CONTACTS: DR. J. L. BURCH             /        DR. R. A. HOFFMAN
                     DEPT. OF SPACE SCIENCES              CODE 696
                     SOUTHWEST RESEARCH INST.             NASA/GSFC
                     P.O. DRAWER 28510                    GREENBELT, MD 20771
                     SAN ANTONIO, TX 78284                PHONE: 301-286-7386
                                                          SPAN DE696::U6RAH

SOURCE_CHARACTERISTICS:

  A. DESCRIPTION_OF_SPACECRAFT:
  The Dynamics Explorer 1 spacecraft was one of two satellites launched for
  the Dynamics Explorer program.  The two spacecraft were launched together
  into coplanar polar orbits for the purpose of studying coupling between the
  magnetosphere, ionosphere, and the atmosphere.  The DE-1 spacecraft was
  placed in a highly elliptical orbit whereas the DE-2 spacecraft had an orbit
  with low ellipticity.
  Instruments aboard the DE-1 spacecraft were: magnetometer (MAGA), plasma wave
  instrument (PWI), spin-scan auroral imager (SAI), retarding ion mass
  spectrometer (RIMS), high-altitude plasma instrument (HAPI), and hot plasma
  composition instrument (EICS - energetic ion composition spectrometer).

  B. ORBIT_INFORMATION:
  Because the Delta launch vehicle did not complete a full burn, the DE-1
  satellite was placed in a lower than anticipated polar orbit, initially
  23173 by 570 km.  The orbital period was 409 min.  The DE-1 and DE-2 satel-
  lites were launched by the same vehicle so that their orbits would be
  coplanar, allowing occasional two-point measurements along magnetic field
  lines. The DE-1 spacecraft spun at a rate of 10 rpm and the spin axis was
  perpendicular to the orbital plane.   The apogee latitude precessed through
  360 degrees in 3 years.  The apogee was positioned over the north pole on
  September 8, 1981.

  C. PERFORMANCE:
  The DE-1 spacecraft performed well through its lifetime. The launch was on
  Aug. 3, 1981 and the satellite ceased science operations on Feb. 26, 1991.
  Power limitations forced the duty cycle to be limited such that the
  instruments were not on continuously.  The initial average duty cycle was over
  90%, but this decreased over the lifetime to about 20% at the end of life.

INVESTIGATION_OBJECTIVES:
  The objectives of the High Altitude Plasma investigation are to contribute to
  the Dynamics Explorer mission goals to provide high-resolution phase-space
  measurements of electrons and positive ions over the energy range from 5 eV
  to 32 keV.  These measurements, along with supporting measurements from other
  instruments on DE-A and DE-B, primarily address the identification of the
  charge carriers of Birkeland currents by the high-latitude plasma populations,
  the transport of plasma through the mid-altitude cusp and into the polar cap,
  the upward mass flow from the ionosphere into the hot plasma population of the
  magnetosphere, and resonant interactions between hot plasma and natural and
  artificially-injected plasma waves and electromagnetic waves. ( Refer to
  J. L. Burch et. al., Space Science Instrumentation Vol. 5, No. 4, 1981,
  pp. 455-456).

INSTRUMENT_ATTRIBUTES:

  A. DESCRIPTION_OF_INSTRUMENT:
  The High Altitude Plasma Instrument (HAPI) consisted of an array of 5
  parabolic electrostatic analyzers lying in a plane containing the spacecraft
  spin axis, and spanning 90 degrees in angle.
  Each parabolic analyzer was followed by two channel electron multipliers to
  measure simultaneously electrons and positive ions.
  The basic mode of operation provided a 32-point energy spectrum every
  one-half second between 5 eV and 32 keV by stepping through 32 sets of
  voltages on the analyzer plates on a logarithmic scale each half second.
  No more than 8 of the 10 sensors were used at one time; typically, 3 electron
  and 5 ion detectors were monitored.  The detectors sampled, sampling rate,
  voltage levels, etc. could be changed on command allowing a large variety of
  modes.

  B. OPERATIONAL_MODE:
  Operation modes were normally selected to emphasize either high angular
  resolution or high temporal (and spatial) resolution.
  1. HIGH_ANGULAR_RESOLUTION_MODE:
     In this mode, the programmable power supply (PPS) was stepped each time a
     nadir pulse was received from the spacecraft.  That is, a single energy was
     sampled every 0.93 degree for an entire spacecraft spin period.  This
     mode was used primarily near apogee for studies of the loss-cone effects
     of wave-particle interactions and for detection of ion beams produced by
     the upward acceleration of ionospheric ions.
  2. HIGH_TEMPORAL_RESOLUTION_MODE:
     In this mode, multiple energy spectra were required during each spacecraft
     spin.  Typically 24 16-point energy spectra, each covering 15 degree of
     spacecraft spin were measured during each spin period.  An increase to 32
     energy steps, covering the full energy range of the instrument, decreased
     the angular resolution to 30 degrees of spacecraft spin.

  C. MEASURED_PARAMETERS:
  Outputs from pulse amplifiers in the detector modules were converted into an
  8-bit compressed telemetry word using a quasi-logarithmic compression scheme.
  A decompression algorithm is used to calculate a decimal count rate, and with
  appropriate geometric factors, accumulation times and detector efficiencies,
  various types of fluxes can be derived as a function of energy.  These fluxes
  are described in the file FORMAT.SFD and include the calculations via
  software provided of the differential number flux, the differential energy
  flux, and the phase space density.
  The distribution function can be derived from the phase space density data by
  contouring the density in velocity space.  Software is not provided for this
  last calculation.

  D. PERFORMANCE_OF_THE_INSTRUMENT:
  The HAPI instrument initially performed very well after the spacecraft was
  launched.  However, no data were received after December 1, 1981 due to high
  voltage power failure.

  E. RESOLUTION:
  Each SATM record contains one DE-1 major telemetry frame (8 seconds) of data.
  The HAPI stepping power supply always provided voltages to the electrostatic
  analyzers at a rate of 64 steps per second.  It had the capability of
  producing a staircase of 64 different steps to cover the energy range from
  5 eV to 32 keV on a logarithmic scale.  However, typically 32 (or 16) of the
  steps were used by skipping some of the steps, allowing two (or four) sweeps
  through the energy range per second.

  PARAMETERS:
  The SATM files contain:  The date and time of the start of each record, the
  number of sensors which were operating, each sensor's ID number, the
  energy step rate, skip rate, start step, and stop step, orbit/attitude
  information, nadir pulse times, magnetic field data, counts from the sensors,
  and energy step numbers.
  ( Refer to Dynamics Explorer-1, HAPI/LAPI Data Processing Software System I.
  High Altitude Plasma Instrument (HAPI), CSC documentation CSC/TM-82/6132,
  Section 2).

  It should be noted that the SATM files do not contain geophysically meaningful
  parameters from the HAPI instrument. Such parameters, as described in (C.
  MEASURED PARAMETERS), are obtained via the software provided which reads the
  SATM files and calculates the parameters.  The magnetic field parameters are
  only used for the calculation of the pitch angles of the detectors.

  DATA_SET_QUALITY:
  There have been few problems with data quality.  There is about a 5% error in
  the calibration.

  DATA_PROCESSING_OVERVIEW:

  A. DATA_PROCESSING_CYCLE:
  The Stand Alone Telemetry (SATM) files were generated directly from DE-1
  Telemetry files stored on optical disks and merged with orbit data from the
  DE Orbit/Attitude database.

  B. HISTORY:
  The original HAPI SATM file database was generated on the DE Sigma-9 computer.
  The Sigma-9 software had problems dealing with time gaps and telemetry errors,
  and produced fragmented files (several files per pass).  Mission Analysis
  Files (MAFs) were also generated on the Sigma-9 and used for analysis and
  plotting.

  In 1992, the HAPI SATM database was regenerated on a microVax computer to
  correct these problems.  Only a few of the old Sigma-9 files are still in
  use where new SATM files could not be generated.  However these have been
  converted to the new SATM format.  These are marked by the letter D in the
  SATM file name. (See NAMING_CONVENTION.)  These SATM files may be incomplete.

  The rest of the old Sigma-9 files, as well as MAFs are no longer in use.
  A new, more efficient file structure was used allowing easier access and
  reducing file size.  See the file FORMAT.SFD for information concerning the
  HAPI SATM files.

DATA_SET_NAME: HAPI STAND-ALONE TELEMETRY FILES (SATM)
DATA_USAGE:
DATA_ORGANIZATION: Are described in FORMAT.SFD .

TIME_SPAN_OF_THE_DATA: 20-AUG-1981 TO 01-DEC-1981

TYPE_OF_FILE_RELATIONSHIP:
All the HAPI instrument data are contained in SATM files.

TIME_GAPS:
There are occasionally time gaps between major frames.  This is due to the fact
that bad major frames were not written to the SATM files.  Care should be taken
in checking for time gaps when analyzing the data.

SOFTWARE_TO_UNPACK_THE_DATA: The utility is included in HLAPI_SOFTWARE.TAR-GZ
that must be uncompressed and untarred (zcat hlapi_software.tar-gz | tar xvf -)
and stored in your local directory.  Instructions on how to use the
software can be found in the file HOW_TO_USE_REDUCE_SATM.TXT in the HAPI 
directory.

SOFTWARE_APPLICATION_SCOPE:  This utility applies to all the data files, i.e.
those that can be named (using wildcards, and "/" to denote directory levels)
/HAPI/8*/*.SATM .

CCSD$$MARKERMRK**002CCSD3KS00002MRK**003

LOG_VOL_COVERAGE: 1981-11-05 TO 1981-12-01

General Note: Inspecting the names of the directories that are subordinate to
the HAPI directory will directly indicate the dates of the data covered in the
given volume.  For example, on the first side (HAPI01) one of the directories
is named:

81228_81257

This means that the data covered in the directory is "from 1981, 228th day
through 1981, 257th day, inclusive."

The three platter-sides are named HAPI01, HAPI02, and HAPI03.  The directories
on the three platter-sides are:

(HAPI01)        (HAPI02)        (HAPI03)
81228_81257    81285_81288      81309_81312
81258_81263    81289_81292      81313_81316
81264_81269    81293_81296      81317_81321
81270_81275    81297_81300      81322_81325
81276_81279    81301_81304      81326_81330
81280_81284    81305_81308      81331_81335

There are two files that list the names/time-coverages/directories of the data
files (*.SATM).  One of these files lists this information for the "current"
platter-side, and the other file lists this for all three platter sides.  The
format of these two lists is the same, and is described in the file
LISTFORM.SFD .

TYPES_OF_DATA_FILES_INCLUDED:  HAPI SATM FILES ONLY

SATM_TIME_COVERAGE:
    1981-11-05T01:30:51 TO 1981-12-01T12:57:37

NAMING_CONVENTION:
  The start day and time are encoded in the HAPI SATM filename. Each HAPI SATM
  filename is in the following format:  'HyrdayhhmmB.SATM'
   H    - indicates a HAPI file ( all files in this dataset are H)
   yr   - the last two digits of the year, i.e., 81 for 1981
   day  - the Julian day (Jan 1 = 001)
   hh   - the starting hour of the file
   mm   - the starting minute of the file
   B    - the production version of the file.  Most files in this data set are 
          B, the few files from the Sigma-9 are D.  Further information may 
          be found in DATA_PROCESSING_OVERVIEW (above), in subsection B,
          "HISTORY".
   SATM - the extension, indicating it is a Stand Alone Telemetry file

  For example:  H812820506B.SATM would be a HAPI SATM file which started at 
  5:06 on Julian day 282 in 1981.

FILE_TIME_COVERAGE:
See LOG_VOL_COVERAGE, above, and
See NAMING_CONVENTION, above, and
See file THIS_SIDE_.DATA_FILE_LIST, and
See file ALL_3_SIDES.DATA_FILE_LIST.

OTHER_LOG_VOL_COVERAGE:
       1981-08-16 TO 1981-10-11
       1981-10-12 TO 1981-11-04

CCSD$$MARKERMRK**003CCSD3RF0000300000001

REFERENCETYPE=$CCSDS2;

LABEL=ATTACHED;
REFERENCE="/HAPI/FORMAT.SFD";
REFERENCE="/HAPI/LISTFORM.SFD";

LABEL=CCSD3SF0000200000001;
REFERENCE="/HAPI/HLAPI_SOFTWARE.TAR-GZ-*";
REFERENCE="/HAPI/HOW_TO_USE_REDUCE_SATM.TXT-*";

LABEL=NSSD3IF0018400000001;
REFERENCE="/HAPI/81309_81312/*.SATM-*";
REFERENCE="/HAPI/81313_81316/*.SATM-*";
REFERENCE="/HAPI/81317_81321/*.SATM-*";
REFERENCE="/HAPI/81322_81325/*.SATM-*";
REFERENCE="/HAPI/81326_81330/*.SATM-*";
REFERENCE="/HAPI/81331_81335/*.SATM-*";

LABEL=NSSD3KF0012900000001;
REFERENCE="/HAPI/THIS_SIDE.DATA_FILE_LIST-*";
REFERENCE="/HAPI/ALL_3_SIDES.DATA_FILE_LIST-*";

/* (EOF) */