Document title: Voldesc SFC for NDADS DE EICS data Project: DE NDADS Datatype: EICS Super-EID: DOCUMENT There may be other documents also identified by this super-EID. NDADS filename: EICS_VOLDESC.SFD TRF entry B46581.txt in NSSDC's controlled digital document library. Feb, 1998. Document text follows: ---------------------- CCSDXZLM0001SMARK001CCSDXVNM0002SMRK0001 LOG_VOL_IDENT: USANASANSSDDEA6_0007A LOG_VOL_INITIATION_DATE: 1992-04-21 LOG_VOL_CLOSING_DATE: 1992-06-22 LOG_VOL_CAPACITY: 1_GB/LOGICAL_VOL LOG_VOL_FILE_STRUCTURE: FILES-11 /* VOLUME_DIAMETER: 12_INCHES VOLUME_DRIVE_MFGR_AND_MODEL: OPTIMEM_1000 COMPUTER_MFGR: DIGITAL_EQUIPMENT_CORPORATION OPERATING_SYSTEM: VMS_5.4-2 COMPUTER_SYSTEM: VAX/11-780 TRANSFER_SOFTWARE: SOAR /* TECHNICAL_CONTACT: W_K_PETERSON DEPT_9120_BLDG_255 LOCKHEED_SPACE_SCIENCES_LABORATORY 3251_HANOVER_STREET PALO_ALTO_CALIFORNIA_94301 415-424-3269 /* PREV_LOG_VOLS: USANASANSSDDEA6_0001A USANASANSSDDEA6_0002A USANASANSSDDEA6_0002B USANASANSSDDEA6_0003A USANASANSSDDEA6_0003B USANASANSSDDEA6_0004A USANASANSSDDEA6_0004B USANASANSSDDEA6_0005A USANASANSSDDEA6_0005B USANASANSSDDEA6_0006A USANASANSSDDEA6_0006B /* CCSDXVNM0002EMRK0001CCSDXKNM0002SMRK0003 DATA_SET_NAME: EICS_STAND_ALONE_TELEMETRY_FILE_SYSTEM DATA_SOURCE: DYNAMICS_EXPLORER_1 ENERGETIC_ION_MASS_SPECTROMETER_(EICS) SCIENTIFIC_CONTACT: E_G_SHELLEY DEPT_9120_BLDG_255 LOCKHEED_SPACE_SCIENCES_LABORATORY 3251_HANOVER_STREET PALO_ALTO_CALIFORNIA_94301 415-424-3253 SOURCE_CHARACTERISTICS: The Dynamics Explorer Program and its two satellites, their objectives and other information are Volume 5, Number 4, of Space Science Instrumentation, Published by D. Reidel, 1981. /* ORBIT_INFORMATION: The Dynamics Explorer-1 (DE-1) orbit is nominally 4.65 r/Re x 500 km. with a 90 degree inclination. Apogee precesses at the rate of ~ 1/3 degree per day. Apogee was over the northern polar cap at the time of launch in September 1981. Detailed ephemeris information is available through the EICS_STAND_ALONE_TELEMETRY_FILE_SYSTEM and separately through the National Space Science Data Center. /* PERFORMANCE_AND_DUTY_CYCLE: The DE-1 spacecraft and the EICS instrument were still operating at the time this was written almost 8 years after launch in 1989. The operational duty cycle gradually decreased from nearly 100% at launch to ~20% in 1989. Operations of DE-1 terminated in March, 1991. The last useable data were acqired on February 18, 1991. /* DYNAMICS_EXPLORER_PROGRAM_OBJECTIVES: The DE science team and the EICS instrument team objectives include studies of: 1) The ionosphere as a source of plasma for the magnetosphere 2) The plasma physics of the auroral acceleration region 3) Electrodynamic coupling as a function of substorm phase and IMF direction 4) Dynamical interactions between the thermosphere and the magnetosphere /* INSTRUMENT_ATTRIBUTES: /* INSTRUMENT_ATTRIBUTES_DESCRIPTION_OF_INSTRUMENT: The Energetic Ion Composition Spectrometer (EICS) provides high sensitivity measurements of the mass and energy composition of the ambient energetic (0 eV to 17 keV/e) ion plasma. EICS consists of an electrostatic energy analyzer followed by magnetic sector designed to provide high sensitivity while resolving the principal ion species encountered in the magnetosphere. The sensor is mounted so that it views radially outward in the satellite spin plane, obtaining full pitch angle coverage twice each spin period. The angular resolution is +/- five degrees in the spin plane and somewhat broader in the direction perpendicular to the spin plane. The mass range from below the hydrogen peak to m/q>100 is covered in 64 mass channels. The energy range from spacecraft potential to 17 keV/e is covered in 64 energy settings, 32 logarithmically spaced energies with center energies from ~50 eV/e to ~17 keV/e, and 32 logarithmically spaced input retarding potential settings. A full instrumental description can be found in: /* Shelley, E.G., D.A. Simpson, T.C. Sanders, E. Hertzberg, H. Balsiger, and A. Ghielmetti, The energetic ion mass spectrometer (EICS) for the Dynamics Explorer-A, Space Sci. Instrum. 5, 443, 1981. /* INSTRUMENT_ATTRIBUTES_OPERATIONAL_MODES: The instrument returns, 32 times a second, the mass and energy step settings, the number of counts from the mass and energy settings sampled and the counts from a secondary detector which is always sensitive to all ions. The instrument can be programmed to step through the mass energy range in a wide variety of ways. The most commonly used modes are described at the end of the file: OPTICAL_DEVICE:[EICS]TEXT_DESCRIBING_THE_ANALYSIS_SOFTWARE.TXT /* INSTRUMENT_ATTRIBUTES_MEASURED_PARAMETERS: The instrument count rate is approximately proportional to the number flux of ions sampled. Conversion to geophysically meaningful flux is done by dividing the observed count rate by a set of calibration constants which depend on energy and mass settings of the instrument. Pitch angle is obtained from the direct measurements (in space craft coordinates) of magnetic field made by the MAG-A instrument on DE-1. /* INSTRUMENT_ATTRIBUTES_PERFORMANCE_OF_THE_INSTRUMENT: The EICS instrument has been operating normally since launch. As noted in Shelley et al., Geophys. Res. Lett. 9, p942, 1982, the data in the lowest energy channel, at times, include a spurious count rate from the photoionization of residual neutral gases in the preacceleration region of the spectrometer. These intervals are identified in the data catalog available to SPAN users and also on each volume of EICS Stand Alone Telemetry Files. Information about the data catalog is given on this volume in the file OPTICAL_DEVICE:[EICS]TEXT_DESCRIBING_THE_INDEX_FILE.TXT /* INSTRUMENT_ATTRIBUTES_RESOLUTION: The instrument returns 32 measurements per second. The instrumental mass range is divided into 64 channels, the energy range into 64 distinct energy ranges, and the angular resolution (+/- ~5 degrees). The time required to step sequentially through this range is incompatible with the geophysical phenomena that are the goal of the DE project. The EICS instrument therefore has a number of specialized modes that optimize combinations of energy, angle, and mass resolution to obtain appropriate temporal/spatial resolution for different scientific objectives. See above, INSTRUMENT_ATTRIBUTES_OPERATIONAL_MODES: /* INSTRUMENT_ATTRIBUTES_PARAMETERS: The data archived in the EICS Stand Alone Telemetry System consists of Instrument Count Rates and a program that reads the files and returns fluxes or velocity space densities of selected mass species for specified time intervals with a specified angular resolution. Information about the program, its input, output, and operation are contained on each volume of EICS Stand Alone Telemetry Files in the files OPTICAL_DEVICE:[EICS]TEXT_DESCRIBING_THE_ANALYSIS_SOFTWARE.TXT OPTICAL_DEVICE:[EICS]ANNOTATED_OUTPUT_LISTING.TXT /* INSTRUMENT_ATTRIBUTES_DATA_QUALITY: Summary data quality information is available in a data catalog given in the file: OPTICAL_DEVICE:[EICS]EICSDATA.LIS Information about this data catalog is given on each volume of EICS Stand Alone Telemetry Files in the file OPTICAL_DEVICE:[EICS]TEXT_DESCRIBING_THE_INDEX_FILE.TXT /* DATA_PROCESSING_OVERVIEW: Because of limitations in computer processing power available to the Dynamics Explorer Project, there was never any plan to systematically process all of the telemetry from all of the DE-1 instruments. The DE and EICS science teams used summary plots and other criteria to select intervals of interest. Data from these intervals continues to be converted to the EICS stand alone telemetry format. EICS stand alone telemetry files are therefore not archived in time order. For a selected sub-set of the data the raw telemetry files have been converted into a stand alone telemetry format which contains all of the EICS telemetry, pitch angle information, data quality indicators and selected orbit and attitude parameters from the Sigma Nine orbit and attitude data bases. In July 1989, ~30% of the data acquired had been processed into the EICS_SATF format. In 1992, EICS stand alone telemetry format files resided on over 790 magnetic tapes at the Lockheed Palo Alto Research labs. All of the data from September 15, 1981 to February 1, 1982, most of the data until March 1983 (The end of DE-2 operations) and data from periods of geophysical interest (i.e. PROMISE, CEDAR, etc) had been processed. Data continued to be added to the data base daily. Direct copies of all of the files on several magnetic tapes and appropriate documentation and the software noted above in the section on INSTRUMENT_ATTRIBUTES_PARAMETERS: constitute the data on an optical disk volume submitted for archiving at the National Space Sciences Data Center at the Goddard Space Flight Center. The EICS Stand Alone Telemetry File System consists of compressed data files, two indices, a general purpose code to read the files and produce meaningful geophysical parameters, and documentation files: The documentation describing the system is contained in six files, copies of which are on each volume of EICS Stand Alone Telemetry Files. An expanded overview is in the file: OPTICAL_DEVICE:[EICS]TEXT_DESCRIBING_THE_EICS_SATF_SYSTEM.TXT The other documentation files are OPTICAL_DEVICE:[EICS]TEXT_DESCRIBING_THE_INDEX_FILE.TXT OPTICAL_DEVICE:[EICS]TEXT_DESCRIBING_OPTICAL_VOLUME_INDEX.TXT OPTICAL_DEVICE:[EICS]TEXT_DESCRIBING_THE_ANALYSIS_SOFTWARE.TXT OPTICAL_DEVICE:[EICS]ANNOTATED_OUTPUT_LISTING.TXT OPTICAL_DEVICE:[EICS]FORMAT.SFD The general purpose code that reads and outputs data is written in FORTRAN77 with VAX extensions and VAX PASCAL. This code has been provided on magnetic tape to the National Space Sciences Data Center at NASA/Goddard. The VOLDESC.SFD associated with this volume provides the rest of the information to completely describe the EICS stand alone telemetry system. The basic outline of this documentation is that this file describes the structure and organization on the optical plater of the EICS stand alone telemetry files. An index file [EICS]EICSDATA.lis is an index to the EICS stand alone telemetry files on all optical platters. A description of the content of the index including the summary data quality flags is in the file OPTICAL_DEVICE:[EICS]TEXT_DESCRIBING_THE_INDEX_FILE.TXT A second index file OPTICAL_DEVICE:[EICS]OPTICAL_VOLUME_INDEX.LIS contains tables giving the range of SATF archive tapes on each optical volume and the volume on which the SATF from each tape are archived. The file on each optical volume describes the data on all previously created volumes. The file OPTICAL_DEVICE:[EICS]TEXT_DESCRIBING_OPTICAL_VOLUME_INDEX.TXT describes the format and content of the two tables in the file OPTICAL_DEVICE:[EICS]OPTICAL_VOLUME_INDEX.LIS This last indes file provides the linkage between tape numbers and optical disk logical volumes. The general purpose program that reads the SATF and outputs geophysical information is in the file [EICS]EICS.EXE Instructions on the use of this program are in the file OPTICAL_DEVICE:[EICS]TEXT_DESCRIBING_THE_ANALYSIS_SOFTWARE.TXT and an annotated output listing produced by the general purpose program is in the file OPTICAL_DEVICE:[EICS]ANNOTATED_OUTPUT_LISTING.TXT Partial information on the format of the compressed data files, which appear in subdirectories beginning with 'T', is given in the file OPTICAL_DEVICE:[EICS]FORMAT.SFD Access to these data is intended to be via the software provided in the EICS.EXE file mentioned above, or you may contact NSSDC for the source code. \* DATA_USAGE: See the file on each volume of EICS Stand Alone Telemetry describing the Stand Alone Telemetry System: OPTICAL_DEVICE:[EICS]TEXT_DESCRIBING_THE_EICS_SATF_SYSTEM.TXT \* DATA_ORGANIZATION: See the file on each volume of EICS Stand Alone Telemetry describing the Stand Alone Telemetry System: OPTICAL_DEVICE:[EICS]TEXT_DESCRIBING_THE_EICS_SATF_SYSTEM.TXT \* TYPE_OF_FILE_RELATIONSHIPS: See the file on each volume of EICS Stand Alone Telemetry describing the Stand Alone Telemetry System: OPTICAL_DEVICE:[EICS]TEXT_DESCRIBING_THE_EICS_SATF_SYSTEM.TXT \* CCSDXKNM0002EMRK0003CCSDXKNM0002SMARK005 \* LOG_VOL_TIME_COVERAGE: 1981-11-03 TO 1990-11-16 TYPE_OF_FILE_TIME_COVERAGE: EICS_SATF 1981-09-15 TO 1991-02-18 Each volume of EICS_SATF files contains an index file which lists the time coverage of each individual file. The file naming convention and description of the index are given on each volume in the files: OPTICAL_DEVICE:[EICS]TEXT_DESCRIBING_THE_EICS_SATF_SYSTEM.TXT OPTICAL_DEVICE:[EICS]TEXT_DESCRIBING_THE_INDEX_FILE.TXT \* PREV_LOG_VOL_TIME_COVERAGE: USANASANSSDDEA6_0001A 1981-09-15 TO 1984-09-14 USANASANSSDDEA6_0002A 1981-09-15 TO 1985-06-02 USANASANSSDDEA6_0002B 1981-09-16 TO 1986-07-07 USANASANSSDDEA6_0003A 1981-10-22 TO 1987-05-87 USANASANSSDDEA6_0003B 1981-10-08 TO 1987-10-09 USANASANSSDDEA6_0004A 1981-09-24 TO 1988-04-02 USANASANSSDDEA6_0004B 1981-09-20 TO 1988-08-10 USANASANSSDDEA6_0005A 1982-02-01 TO 1989-06-01 USANASANSSDDEA6_0005B 1982-06-30 TO 1990-05-04 USANASANSSDDEA6_0006A 1981-09-15 TO 1990-07-14 USANASANSSDDEA6_0006B 1981-11-03 TO 1991-02-18 \* CCSDXKNM0002EMARK005CCSDXRNM0003SMARK006 NESTING=L REF=[EICS]FORMAT.SFD REF=[EICS]TEXT_DESCRIBING_THE_INDEX_FILE.TXT REF=[EICS]TEXT_DESCRIBING_OPTICAL_VOLUME_INDEX.TXT REF=[EICS]TEXT_DESCRIBING_THE_ANALYSIS_SOFTWARE.TXT \* CCSDXRNM0003EMARK006CCSDXRLM0003SMRK0007 ADI=CCSD0002 CLASS=S REF=[EICS]TEXT_DESCRIBING_THE_EICS_SATF_SYSTEM.TXT ADI=CCSD0002 CLASS=S REF=[EICS]ANNOTATED_OUTPUT_LISTING.TXT ADI=NSSD0018 CLASS=K REF=[EICS]EICSDATA.LIS ADI=NSSD0019 CLASS=K REF=[EICS]OPTICAL_VOLUME_INDEX.LIS ADI=NSSD0021 CLASS=J REF=[EICS]EICS.EXE ADI=NSSD0022 CLASS=I REF=[EICS.T*]C*.DAT \* CCSDXRLM0003EMRK0007CCSDXZLM0001EMARK001