PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM INSTRUMENT_HOST_NAME = "2001 MARS ODYSSEY" INSTRUMENT_NAME = "GAMMA RAY SPECTROMETER" TARGET_NAME = MARS OBJECT = TEXT PUBLICATION_DATE = 2003-01-01 NOTE = "Introduction to Odyssey GRS CGS Data" END_OBJECT = TEXT END 2001 MARS ODYSSEY GAMMA RAY SPECTROMETER CORRECTED GAMMA SPECTRA Introduction ------------ The Odyssey Gamma Ray Spectrometer (GRS) Corrected Gamma Spectra (CGS) data products are spectra from the Gamma Sensor Head corrected to a common energy scale. These products are generated by processing GRS gamma spectra EDRs (Experiment Data Records -- raw data). Information about the CGS product can be found in the GRS CGS and SGS Software Interface Specification (SIS) in the DOCUMENT directory of this archive. Information about the processing applied to these products can be found in the Gamma Processing document in the same directory. File Formats ------------ The GRS CGS data products are stored as binary files with detached ASCII-text PDS labels. Each file contains corrected spectra acquired over a two-hour time period. Files are grouped into directories by Earth day. The file naming convention for GRS CGS data files is "CGS" followed by a date and hour specifier in the format YYYYMMDD-xx-yy, in which xx and yy are the beginning and ending hours of data acquisition. An example file name is CGS_20020101_00_02.DAT. Each data file is described by a PDS label in a separate file with the same name, extension ".LBL", in the same directory as the data file. The labels contain identification and observation parameters associated with the data files and definitions for the TIME_SERIES objects. The PDS labels include a pointer to a format file that contains column definitions (extension ".FMT"). The format file is found in the LABEL directory. Volume Contents --------------- The GRS CGS archive volume includes the following files and directories. Root directory AAREADME.TXT - the file you are reading ERRATA.TXT - notes and errata, if any VOLDESC.CAT - volume description for the PDS catalog INDEX directory INDXINFO.TXT - description of contents of this directory INDEX.TAB - index of all products in the archive INDEX.LBL - PDS label that describes INDEX.TAB DOCUMENT directory BAD_CODE.TXT - quality flag definitions DOCINFO.TXT - description of contents of this directory GRS-IDR-SIS.PDF - Detailed data product description in PDF format GRS-IDR-SIS.LBL - PDS label for GRS-IDR-SIS.PDF GRS_GAMMA_PROCESSING.PDF - Description of processing applied to CGS products GRS_GAMMA_PROCESSING.LBL - PDS label for GRS_GAMMA_PROCESSING.PDF TIME_CONVERSION_TABLES.PDF - Tables for converting Earth to Mars time TIME_CONVERSION_TABLES.LBL - PDS label for TIME_CONVERSION_TABLES.PDF CATALOG directory CATINFO.TXT - description of contents of this directory *.CAT - descriptions of dataset, instrument, spacecraft, mission, and personnel for the PDS catalog LABEL directory LABINFO.TXT - description of contents of this directory CORR_GAMMA_SPECTRA_COLS.FMT - format of columns in CGS data file SOFTWARE directory GRS_CODE.ZIP - library of Java source code to parse CGS data files GRS_CODE.LBL - PDS label for GRS_CODE.ZIP GRS_CODE_DOC.ZIP - documentation for Java code GRS_CODE_DOC.LBL - PDS label for GRS_CODE_DOC.ZIP SOFTINFO.TXT - description of contents of this directory Data directories Data files are aggregated by day, with a separate subdirectory for each day, named according to the format YYYYMMDD. These subdirectories are in turn grouped into directories by year, with names in the format YYYY. Contacts -------- For questions concerning these data products and documentation, contact: PDS Geosciences Node Washington University Dept. of Earth and Planetary Sciences 1 Brookings Drive St. Louis, MO 63130 314-935-5493 WWW Site: http://pds-geosciences.wustl.edu/ Electronic mail address: geosci@wunder.wustl.edu