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X- and Gamma-Ray Event Data


Availability: Archived at NSSDC, accessible from elsewhere

Time span: 1978-08-12 to 1987-02-07


This is a subset of the entire data set returned from the ICE/ISEE-3 X-ray spectrometer, ostensibly containing all events detectable in the lowest energy scintillator channel (~15 - 30 keV). There is generally one event per file, plus at least some background before and after the event to get a good 2-minute background in the scintillator channels. There is often more than one event per file when there is insufficient background between multiple events. The event files unfortunately do not generally contain the complete flare in the file or sufficient background time at energies below ~ 15 - 30 keV. The measured parameters are photon counting rates in the energy range from 5 keV to 3 MeV.

The Event Tape contains approximately 9324 files. The data set is stored on 1 Exabyte (8-mm) tape cassette. The data are stored in "tar" format, starting 12 Aug. 1978 and ending 7 Feb. 1987. The data volume is ~ 270 MB compressed, and ~ 360 MB uncompressed. Users should obtain the software provided by the PI for handling and analyzing the data, with NSSDC ID 78-079A-14F. This software includes a utility named x_datafile for selecting, extracting and decompressing a desired data file from the Exabyte tapes. The spacecraft was in a heliocentric orbit at the Lagrange libration point between the Earth and Sun until 1984, when the spacecraft was renamed ICE and sent to rendezvous with a comet. Consequently, use of the data requires proper time correction from satellite time to Universal Time (UT), as well as other special corrections described in the users' guide. For a detailed discussion of the instrument, see K. A. Anderson, S. R. Kane, et al., IEEE Trans. on Geosci. Electron., vol. GE-16, no. 3, July 1978. Data are available online at

Alternate Names


    • Astronomy: Cosmic Ray
    • Solar Physics: X-Ray


    • 78-079A-14G

    Additional Information



    Questions and comments about this data collection can be directed to: Dr. H. Kent Hills



    NameRoleOriginal AffiliationE-mail
    Mr. Robert M. CandeyGeneral ContactNASA Goddard Space Flight
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