• These data should be considered a "full-telemetry-resolution" research data product, nominally carrying the complete science content of the GME data telemetry. This data product is the primary working foundation for all GME analyses, although higher-level data products have been built for various purposes. Although intrinsically rich in content, the data are likely to require intensive effort by users to understand and analyze.
• Data consist of two primary product, the so-called "CNTS" (i.e. counts) format files and the so-called "PHAS" (i.e. pulse-height-analysis) format files. All VLET plus full LED and MED rate data are contained in the CNTS files; all LED and MED pulse-height data (with appropriate normalizing rates) are carried on the PHAS format files.
• FTR data run from the first GME data in Oct 1973 to "the present"
  • There is a typical time delay in posting new data of 1-3 months. This delay is due both to the schedule on which IMP-8 telemetry data is collected and shipped, and to time necessary for initial data reduction. As of 5/8/97, data to approx 3/20/97 are online.
• FTR data are available only in a fairly complex binary format. Software and (gradually improving) documentation are available to aid in use of this data.

1. Data Content and Usage (FTR Data)

This data product contains the full science content of the IMP-8 GME measurement set from launch to present. See the instrument description and data descriptions below for additional information.

2. Digital Data Access (FTR Data)

• Access to binary data files (CNTS and PHAS)
• Access to documentation and software

File organization and naming: Each binary file ("type" CNTS or "type" PHAS, abbreviated as "C" and "P" in the binary file names) covers a 4-day span of data. The files are additionally "g-zipped" to compress the data volume. File naming at this time combines the "type" specification with an "interval" number, where interval 101 starts on October 28 1973 and intervals increment sequentially to the present. The concept of intervals originated in the IMP-6 orbit and GME processing strategy. The concept of 4-day intervals was carried over to IMP-8 in the original implementation of the processing system. A table of interval <-> date conversions exists. So e.g. the file C1895.gz in fact includes "CNTS" data from 21-24 June 1993 inclusive.

File Formats:

• CNTS file format
• PHAS file format

Users should be aware these data are in a complex and encoded form that will be difficult to use without acquiring and mastering the software and detailed instrument behavior.

 

3. Analysis Software and Documentation (UNDER CONSTRUCTION):

The source code of all programs are written in Sun FORTRAN and/or C languages. These programs now operate under a Sun 4.1.4 operating system. A makefile which generates the object files and executable programs, is provided. A user's guide for each program provides the general description and input parameters needed. A shell program executes the program. Each program file contains the source codes of each routine, user's guide, makefile, IMP-8 catalog file, and I/O system "FTIO" package object file.

Type	Program and Link to User's Guide	Description	Link to Source Code (Source codes are stored "G-zip'd" TAR files - please save as "source")
Pulse-Height Matrix Displays	HGPLT	High-Gain Plot: Display of IMP8 GME LED and MED pulse-height data in matrix format for select 4-day intervals and special (pre-processed) times, plus distribution histograms used in setting MED gain shift factors	Link
	ANALIMPF	ANALIMP/ANALIMPF: Display of IMP8 GME LED and MED pulse-height data in matrix format (any time span), plus "track-centered" histograms	Link
Processed Parameters (Rates and Fluxes)	RATEPLOT	Rate-Plot: Access to all IMP-8 GME rates (LED, MED and VLET, including sectored rates and every readout mode)	Link
	FLUXPLOT & FLEXPLOT	Flux/Flex Plot: Output of IMP-8 GME LED and MED fluxes from "intermediate flux/flex" format files of bin counts and normalizations. Flux database uses narrower box definitions (most appropriate to galactic cosmic ray and quiet time studies) than the Flex database (which is most appropriate to interplanetary and solar energetic particle studies).	[UNDER CONSTRUCTION]
	FOURIER	Fourier: Sectored data (including fields with optional additional file inputs) and fitted anisotropies	Link
File Output (PC formats)	PCPHA	PC-PHA: Output of pulse-height data in the PC-PHA binary format	Link
	PCRATE	PC-RATE: Output of rate and flux data (from "intermediate" flux or flex files) into the PC-Rate binary format	[UNDER CONSTRUCTION]
	INTFLUX & INTFLEX	Intermediate Flux and Intermediate Flex: Generate files in the flux or flex format for input to FLUXPLOT, FLEXPLOT and PC-RATE	[UNDER CONSTRUCTION]
Utilities	DBTIME	Data Base Time: Time consistency and file quality check utility program	[UNDER CONSTRUCTION]

 

 

Overall Documentation, Processing Overview and Status (PARTIALLY COMPLETE ONLY)

Return to the Top of this page

Return to the GME Data page (and access to additional data products)

Return to IMP-8 GME Home page

Questions or Comments

Contact Information

Questions about GME data and/or instrumentation should be directed to the NASA Principal Investigator:

Dr. Robert E. McGuire (at Robert.E.McGuire@nasa.gov)

Head, Space Physics Data Facility
Code 672
NASA/Goddard Space Flight Center
Greenbelt MD 20771 USA

 

Phone (with phonemail): 301-286-7794

Last Modified: Wednesday 5/7/97 (REM)